Category: Sciences 2502

Introduction and Choice of article

The article that has been selected for this essay is, Rice scientists create a super antioxidant  Common catalyst cerium oxide opens door to nanochemistry for medicine. The article was published in Rice University News and Media on October 14^th 2013 where it was posted in the Featured Stories section. The author is Mike Williams who is a senior media relations specialist working at the Rice University in the Public affairs department (Williams 1). The article was selected based on the issues of nanochemistry that it has discussed in details. It has also been chosen based on its straightforward method of presentation of research findings. The article is a summary of the research on nanochemistry that was done in the university, and is hence appropriate for discussion in the essay. This essay looks at the assumptions, conclusions, and implications from the article.

Assumptions and Purpose

The authors purpose of writing the essay is to demonstrate the application of nanochemistry in medicine. The use of nanochemistry has largely been in other fields apart from medicine (Koji, Yoshida and Ikuhara 1, Babentsov 31). The author intends to show how breakthroughs at the university will make it possible to use this technology in the health sector. The other purpose of the study is to demonstrate progress that has been made at the university.

The author does not indicate the purpose of writing the article. Besides, he does not provide an explicit explanation of why he does not give it. For readers who are going through the article, the purpose may be interpreted from the authors phrase based on the way they explain some of the contents. Therefore, the purpose of the study is implied. Researchers and other authors should state the purpose of their studies clearly and hence the need for introduction and abstract.

The key question that the author is trying to answer is whether nanochemistry can be applied in medicine. He provides evidence to support the available answers, especially the scientific evidence that shows successful studies on the use of antioxidants. The question the author raises is answered in his subsequent discussions. He qualifies the assumptions that he has made in his article.

The authors main point of view in the article is that the application of nanochemistry in medicine is a potentially beneficial breakthrough. A point of view guides the author in making the right assumptions in his article (Laramee 2366). The author also lauds the research on Cerium oxide nanocrystals by stating that the results will mean a lot to cancer patients. Previous studies on the use of safe and efficient use of products to treat post radiation injury have not been fruitful.

In this article, the author is aware of the alternative and conflicting views in the article. He shows sensitivity to these views. This observation is one of the characteristics of a good author who aims at attracting an audience by passing information appropriately (Laramee 2366). While he lauds the research on the use of nanochemistry in medicine, he states some of the existing products that serve the same function (Williams 1).

The most significant assumption that the author made is that readers are aware of the existing interventions in medicine and some of the works done in nanochemistry. The author states that the existing interventions in the treatment of radiation injury are not as effective as the use of cerium oxide nanocrystals (Williams 1). He also assumes that readers are aware of some of the components of the catalytic converters in cars. The assumptions made in the article are justifiable. Hence, most readers will understand the article when given the chance to read it. The assumption that the discussed medical interventions are common can be justified by the explanation that the author provides.

Conclusions and Implications

The author concludes that the application of nanochemistry in medicine is of potential benefit to some patients, especially those who are on treatment for cancers on radiotherapy. He also concludes that the research on cerium oxide nanocrystals will benefit the medical world where redox reactions will provide antioxidant effects. Some of the individuals who would benefit according to the author include patients who suffer traumatic brain injury, those with Alzheimers, and those who have heart attacks (Williams 2). The author generally concludes that the discovery of the nanochemicals and their use in medicine is a progressive finding.

The article communicates scientific reasoning and chemistry concepts clearly, even to the readers who may not have the basic knowledge in these areas. According to Patterson, scientists who intend to produce materials for the public should target to make their information easy for the audience (23). The author communicates the findings of the research on cerium oxide nanocrystals, especially where he states that the catalysts are commonly found in motor vehicles. The concepts under discussion are clear in the article because the author uses easy concepts. He also provides the findings of the research besides explaining them.

The author offers a convincing line of argument to arrive at the conclusion at the end of the article. The basis of the argument is scientific evidence that is provided in the research that the author provides. According to Lamb, any conclusions that the author makes should have scientific backing, most likely from a peer reviewed research (91). The author in this article supports his arguments through such methods, with the only evidence being the research quoted in the paper. The author supports the assumptions that are made in the paper.

A number of references and conclusions are possible from the article by Williams. One of the main conclusions is that the research by the university was a successful one that led to the discovery of important uses for nanochemistry. Williams provides an important basis for the use of nanochemistry in medicine by focusing on the study in the article (1). Another conclusion is that the article is well structured with enough evidence to support the findings that the researcher provides. The author provides an update on the new advances in medicine in the use of nanochemistry in the field.

If the authors reasoning is accepted, a consequence is that more attention will be given to the use of nanochemistry in medicine. The credibility of the research that he discusses will also increase, thus making the use of this intervention more common. The other consequence of the article is that there will be more evidence to support the use of nanochemistry. If rejected, the authors views will also have some consequences. One of them is that the quoted research will lose credibility, especially from the personal point of view. The other consequence of rejecting the authors reasoning is that there will be the effect of conducting a second study to prove the findings in the first study.

In conclusion, the article is well presented. It uses sound scientific evidence to support the authors intended message. The research that the article focuses on is a progressive one in the field of medicine and nanochemistry. Hence, the article is a good summary of this research.

Works Cited

Babentsov, Nigel. Dislocation Emission Caused By Different Types Of Nanoscale Deformation Defects In Cdte. Semiconductor Physics, Quantum Electronics & Optoelectronics 17.1(2014): 29-33. Print.

Koji, Matsui, Yoshida Hidehiro, and Ikuhara Yuichi. Nanocrystalline, Ultra-Degradation- Resistant Zirconia: Its Grain Boundary Nanostructure And Nanochemistry. Scientific Reports 1.1(2014): 1. Print.

Lamb, David. Promoting The Case For Using A Research Journal To Document And Reflect On The Research Experience. Electronic Journal Of Business Research Methods 11.2(2013): 84-92. Print.

Laramee, Robert. How To Write A Visualization Research Paper: A Starting Point. Computer Graphics Forum 29.8(2010): 2363-2371. Print.

Patterson, David. The Health Of Research Conferences And The Dearth Of Big Idea Papers. Communications Of The ACM 47.12(2004): 23-24. Print.

Williams, Mike. Rice scientists create a super antioxidant. Rice University News & amp; Media, 2013. Web.

Summary

This paper aims to generate a process for analysis of the data collected in previous works resulting in the concise and proper analysis and development of the data implementation into a workable plan. In order to create a comprehensible project, it seems appropriate to apply the table format.

A review of the data

The core concepts of the research are time is muscle and the golden hour theory that reveal the fact that time is the main decisive factor during the period of medical contact. First of all, the research focuses on determining the DTB in STEMI patients. After that, it was stated that there is a need for the enhancement of primary PCI. Hospital leadership is the first area to be improved as it plays a paramount role in change management. Besides, organizational and political issues such as the personnel training and action plan require improvement as well. Individualistic behaviors of the staff members should be eliminated in order to create an integrated team that would collaborate effectively. Moreover, one might note the necessity to develop the overall change strategy concerning all the vital issues connected to the topic. It is also should be pointed out that communication is one of the most significant aspects of the change plan, the appropriate implementation of which would promote cooperation as well as the decrease of the DTB in the STEMI patient.

The method of the research and rationale

The study applies a mixed design of the investigation. A qualitative method involves the collection of information in a free form received from physicians, administrators, and nursing staff; it focuses on the understanding, explanation, and interpretation of empirical data that is the source of speculation and productive ideas. A quantitative method comprises conducting various surveys based on the use of structured questions of closed type, which corresponds to a large number of respondents. The main objective of quantitative research is to obtain a numerical estimate of the issue or the reaction of respondents towards it. In particular, the study uses Mann-Whitney and Chi-square tests. Consequently, the quantitative representation would be accompanied by the qualitative explanation of the situation.

The rationale of the study is caused by the need to examine the issue of the DTB in STEMI patients and improve it to 45-60 minutes as the mortality rate from cardiovascular diseases remains high.

A process for analyzing the data

Among the resources that might help to analyze, develop, and implement the collected data, one might mention the Mann-Whitney U test. It is a nonparametric criterion and, in contrast to the Student t-test, does not require the normal distribution of the compared populations and would be used to represent and assess median periods. Therefore, the application of the above test seems rather relevant to the study.

The data analysis plan would also include the Chi-square test which is a method allowing to evaluate the significance of differences between the actual (identified by the study) number of outcomes or quality characteristics of the sample falling into each category and the theoretical amount that can be expected in the studied groups with the null hypothesis. In other words, it is a method evaluating the statistical significance of the categorical data of differences between two groups identified in the study.

In addition, it seems appropriate to use thematic analysis to analyze the qualitative data. It would reflect the current situation and help in developing the perspective action plan in the area of the hospitals organizational culture.

A plan to integrate the data into the change project

According to the collected data, it seems important to use the concept of Lean as a Quality Improvement Tool to decrease the D2B time. Besides, the implementation of Six Sigma also contributes to the reduction of the D2B time. In addition, it is of great importance to developing special programs and procedures that would involve medical personnel stakeholders to collaborate and improve the reperfusion period. The awareness and the reaction space of the hospital should be increased to provide patients with timely emergency health care. According to Joost, Blumrath, and Radke (2012), respective training of staff members lead to a significant reduction in DTB intervals (p. 140). It was also stated that the STEMI receiving centers should work on a 24/7 basis and should be equipped with professional cardiologists (Savage, Raffel, Walters, & Gough, 2010). What is more important, in spite of ACC/AHA guidelines, it seems necessary to implement 45 to 60 minutes D2B. Stowens, Sonnad, and Rosenbaum (2015) state that using EMS dispatch to note STEMI patients decreases D2B intervals. According to the results of the study, the above measure was reduced lower than 60 minutes.

Before starting the change project, it is of great importance to evaluate the changing context. Precisely speaking, organizational, environmental, and readiness to change components should be assessed. A head nurse should complete the vision of the change plan along with its outcomes. After that, the change management should be considered taking into account objectives, resources, and staff training. Additionally, potential gaps and feedback should be considered.

References

Joost, A., Blumrath, C., & Radke, P. (2012). TCT-485 A simple strategy to significantly reduce the door-to-balloon time in patients with acute ST-elevation myocardial infarction. Journal of the American College of Cardiology, 60(17), 140-142.

Savage, M., Raffel, C., Walters, D., & Gough, C. (2010). Pre-hospital Ambulance Notification of ST-Elevation Myocardial Infarction (STEMI) Significantly Improves Door to Balloon Time (DTB) for Primary Percutaneous Coronary Intervention (PPCI)Australian Setting. Heart, Lung and Circulation, 19(2), 244-245.

Stowens, J., Sonnad, S., & Rosenbaum, R. (2015). Using EMS Dispatch to Trigger STEMI Alerts Decreases Door-to-Balloon Times. Western Journal of Emergency Medicine, 16(3), 472-480.

Continental plates are constantly moving which leads to a series of natural occurrences. One of these occurrences is the earthquake, which results from sudden contractions along the fault lines. Therefore, these sudden contractions transfer from their epicenter in form of seismic waves. According to Brûlé et al. (2017), there are four basic seismic wave types that a seismograph may detect. They include P-waves, S-waves, Rayleigh waves, and Love waves. However, the distinctiveness of these ripples is based on their magnitude.

P-waves are of the greatest magnitude; thus, they are recorded first in the seismograph on the occurrence of an earthquake. However, P-waves compress and expand through their medium of traversing. They travel through the air, taking the form of sound waves of 330 meters per second (Vallée et al., 2017). S-waves also referred to as secondary waves, are traverse ripples that travel at an angle by either shearing or shaking. Here, particles through which the waves are traveling are perpendicular to the waves direction (Vallée et al., 2017). They record a lower magnitude in the seismograph than the primary ripples and are more dangerous compared to p-waves.

Surface waves come in two forms that are the Rayleigh and Love waves. They are surface waves since they originate and traverse close to the surface. Because of their magnitude, they record last in the seismograph (Brûlé et al., 2017). However, slower than secondary waves, surface ripples prove to be more destructive when they strike, for they have a higher amplitude. Rayleigh waves traverse as ripples resembling those formed on water pools. Love waves lead to horizontal shearing of the ground (Vallée et al., 2017). However, people claim to have observed Rayleigh and Love seismic waves in open spaces such as parking lots. The figure below shows the four types of waves discussed above.

References

Brûlé, S., Javelaud, E. H., Enoch, S., & Guenneau, S. (2017). Flat lens effect on seismic waves propagation in the subsoil. Scientific Reports, 7(1), 1-9.

Vallée, M., Ampuero, J. P., Juhel, K., Bernard, P., Montagner, J. P., & Barsuglia, M. (2017). Observations and modeling of the elastogravity signals preceding direct seismic waves. Science, 358(6367), 1164-1168.

Objective and Overview

The goal of this lab is to produce a sample of pure aspirin crystals. Towards achieving this, the experiment utilizes the reaction of the salicylic acid with acetic anhydride, which yields aspirin and acetic acid. The word and chemical equation for the reaction can be illustrated as follows:

Salicylicacid + Acetic anhydride ’ Aspirin + Aceticacia

Concentrated sulfuric acid is utilized to speed up the reaction.

Apparatus and Reagents

• Salicylic acid
• Acetic anhydride
• Concentrated sulfuric acid
• 600ml beaker
• 100ml beaker
• Ethanol
• 125ml conical flask
• 100ml conical flask
• 10ml measuring cylinder
• Teat pipette
• Ice cubes
• Rough balance
• Buchner apparatus
• Aspirator
• Ring stand
• Iron clamp
• Filter paper
• Glass stirring rod
• Rubber policeman
• Deionized water
• Thermometer
• Stopwatch

Preparation of the Crude Aspirin

1. Create a thermostatic water bath by adding 100ml of water into a 600ml beaker and heating it to about 70⁰C, as shown below.

2. Weigh approximately 4.0g of salicylic acid in a 125ml conical flask and record it.
3. Using the 10ml measuring cylinder, add 5ml of acetic anhydride to the conical flask.
4. Using the teat pipette, add approximately 5 drops of the concentrated sulfuric acid to the conical flask.
5. Swirl the mixture slightly and place the conical flask in the hot water bath. Ensure the conical flask is clamped to a ring stand, constant stirring with a glass rod for the complete dissolving of the solids, and the mixture heats up for about 10 minutes.
6. Take out the conical flask from the water bath and keep it uninterrupted to permit crystallization at room temperature.
7. When crystal formation stops, add and thoroughly twirl about 20ml of ice water to precipitate out the insoluble aspirin and tear down the acetic anhydride that failed to react.
8. Transfer the solution to a 100ml beaker in readiness for product dissociation from the mixture.

Aspirin Separation from the Mixture

9. Use the Buchner apparatus to sieve off and collect the aspirin crystals through the vacuum filtration process.
10. Set up the Buchner apparatus as below by clamping the side-arm conical flask to the ring stand. Fix one end of a rubber tube to the side-arm and the other end to the aspirator. Insert a Buchner funnel into the flask, fasten it with a rubber stopper and fix an appropriately fitting filter paper. Make sure the paper is rinsed with distilled to ensure it sticks to the apparatus.

11. Switch on the aspirator to full blast, whirl the flask with aspirin and pour it on the filter paper. Using the rubber policeman, pickle out the superfluous precipitate in the flask. Rinse the sample on the filter paper with chilled water and leave set up to run for about 5 minutes.
12. Wash the obtained aspirin with 5ml of cold water for at least three times, followed by a single 5ml of ethanol to do away with the impurities.
13. Let the crude aspirin desiccate, use the rough balance to weigh it, and record the mass.

Purification of Aspirin via Recrystallization

14. Measure about 5ml of ethanol using a measuring cylinder, add it to 100ml conical flask and warm it to 70⁰C.
15. Using a spatula, add about 3g of the collected crude aspirin into the flask and warm the mixture until all crystals dissolve.
16. Add about 10ml of deionized water to ensure all particles dissolve and allow the solution to cool slowly in an ice bath.
17. Upon completion of crystallization, amass the pure aspirin crystals via the vacuum filtration and allow them to dry.

Risk Assessment for the Experiment

1. The practical should be carried out in a fume hood as the material used are hazardous.
2. Protective clothing like goggles and gloves should be worn as acetic anhydride causes an irritating effect on the eyes and skin.
3. No flame should be used to heat the ethanol as it is highly combustible.
4. All the waste products and materials should be deposited in the organic waste bins.
5. The aspirin synthesized in this practical is impure and should not be injected.

Works Cited

Chemistry 104: Synthesis of Aspirin. Chem.Latech.Edu, 2020, Web.

Csun.Edu, 2020, Web.

Laney.Edu, 2020, Web.

Montinari, Maria Rosa, Sergio Minelli, and Raffaele De Caterina. The first 3500 years of Aspirin History from its RootsA Concise Summary. Vascular pharmacology 113 2019: 1-8.

Roberts, Tracey et al. Acetylsalicylic Acid (Aspirin) for Schizophrenia. Cochrane Database of Systematic Reviews, 2016. Wiley, Web.

Results and Discussion

The key results of this laboratory work were direct measurements of analytical signals from fatty acid esters obtained using the classical instrumental GC/MS method. Since it is well known that this technique uses a reference method, the organic methyl caprate with a reference peak value was chosen as the internal standard¹. Since GC/MS focuses on using the molar mass of the molecule as one of the central predictors of substance movement across the chromatographic column, the weights of the mixture components analyzed were emphasized in the present laboratory work. Table 1 clearly summarizes the list of the four esters used in the experiment.

Table 1. Summary of the standard solutions used.

It should be noted that the methyl caprate in the first row was used as the reference material against which the subsequent calculations for the three fatty acid esters were made. As can be seen in Table 1, there is an unambiguous relationship between the molecular weight of the sample and the retention time on the chromatographic column. The heavier the molecule, the lower its rate of movement, and thus the more significant the time required to elute the substance. This relationship was confirmed for the four substances studied, for which the heaviest, methyl arachidate, had approximately twice as much total retention time as the lightest, methyl caprate. Consequently, it can be assumed with high probability that there is a positive linear relationship between the molecular weight of the sample and the retention time metric.

In the present laboratory work, registration of the analytical signal was performed using a mass spectrometer, which determines the signal intensity depending on the fragmentation of the molecule. Thus, it is known that the more complex and massive the substance, the more diverse the final mass spectrogram. More specifically, for a mixture of four standard solutions (three esters and one internal standard), the spectrogram shown in Figure 1 was obtained. Analysis of this Figure allows us to determine that the area of each of the peaks is different and is determined mainly by its height. Thus, the more intense the signal from the sample was, the larger the area it could have as a result. In addition, the concentration of the substance also played an essential role in the formation of the peak since it directly contributed to the overall rate of movement of the molecules and thus affected the intensity of the signal.

The ratio of the peak area of the standard solution to the peak area of the internal standard was defined as the peak ratio. In order to determine the dependence of the peak ratio on the concentration of the dissolved substance, a linear regression model was used. Figures 2, 3, and 4 show plots of the dependence of the peak ratio on the concentration of the corresponding fatty acid ester. In general, it can be seen that each of the Figures can describe the dependence with relatively low reliability. The best fit of the linear regression model was found for the heaviest molecule, that is, methyl arachidate.

Finally, it should be noted that the use of standard solutions of fatty acid esters was conditioned by the assumption that the unknown concentration of the substance could be determined by means of a calibration graph. For this purpose, a portion of the combined mixture of the known standard and some solution of unknown concentration was introduced into the GC/MS analyzer. The calculated new peak area, when divided by the peak area of the mixture of the internal standard with the unknown, gave a new peak ratio for each ester in a series of three measurements with a difference in volume. The final Table 2 is a summary of all three lines of the experiment. The third column provided information regarding the concentration (ppm) of the corresponding ester in the mixture, while the fourth column summarizes the concentrations of the unknown additive.

Summary

In the present laboratory work, the possibilities of practical chemical analysis of substances using a GC/MS unit were investigated. It was shown that the retention time of the substance in the chromatographic column is a value linearly dependent on the molecular weight. In more detail, the heavier the molecular weight of the substance, the longer it eluted. In addition, standard solutions were used to construct gradient plots in order to subsequently determine the fatty acid ester concentration in each of the mixtures with the unknown. Since the linear regression model did not have high reliability for all experimental lines (the highest figure was R2 = 0.7064), one cannot unequivocally judge the value of the data obtained. Finally, it was shown that the concentration of the substance was related to the peak area on the spectrogram: this relationship was due to the inhibitory effect that increasing the concentration had on the velocity of the molecules in the column.

Reference

Avula, S. G. C.; Belovich, J. M.; Xu, Y. Determination of Fatty Acid Methyl Esters Derived from Algae Scenedesmus Dimorphus Biomass by GCMS with OneStep Esterification of Free Fatty Acids and Transesterification of Glycerolipids. J. Sep. Sci. 2017, 40(10), 2214-2227.

Appendix 1. Answers to Questions

Why is it important to not exceed 250 °C in the temperature program?

The higher the temperature used, the more likely noise and decreased sensitivity of the assay. Thermal decomposition of analytes is indeed the target action, but excessively high temperature will lead to complete decomposition of the substance.

Explain why the stationary phases in GC/MS are chemically bonded and cross-linked?

The bound and cross-linked structure of the stationary phases ensures that the sorbent cannot flow out and is, therefore, more stable. This includes thermal stability, resistance to solvents, and mechanical bonding of the phase.

Why is an interface needed between the gas chromatograph and the mass spectrometer?

The separation between the gas chromatography and mass spectroscopy chambers allows the integrity of each interface to be achieved and reduces the potential for errors and noise caused by adjacent processes.

Why is it important to periodically autotune the mass selective detector (MSD)??

All instrument components clog and deteriorate over time, so regular checks, cleanings, and calibrations are essential in achieving reliable analysis results. The auto-tuning algorithm is used to provide a consistent response to the measured compound with high sensitivity and mass accuracy, which means the regularity of this process determines the quality of the data.

What is the advantage of using the internal standard method? Why is methyl caprate used as the internal standard?

The internal standard method has key advantages: it is more accurate and less prone to errors due to instrument instability, permanent substance additions, or sample preparation procedure. In addition, the use of this method reduces the laboriousness of measurements in the case of group determinations. Methyl caprate can be used as an internal standard because it has a relatively unbranched organic structure and low mass.

Abstract

In this paper, specific conditions for palladium as well as silver deposition were determined. Also, the simultaneous, co-deposition of the same was determined for hydrazine-based solution bearing both element precursors. The electroless plating kinetics for simultaneous, co-depositions for both elements in the mixture were determined. Moreover, a mathematical model to determine the membrane thickness, the rate of plating and, composition of profile with respect to plating parameters were developed as well as the structural evolution in the course of plating was also investigated (Cheng and Yeung, 127). As such, a hydrogen permeation study revealed that given common thickness, a composite membrane of Pd/Ag dwarfs pure palladium membrane in performance. Additionally, with all the factors constant, the performance of the membrane is invertedly proportional to the membranes thickness.

Focus of the paper

In a synopsis, this paper focuses on a glimpse of the background information about flexible thin membranes, eventually narrowing down to the process of manufacture of Palladium-silver composite membrane in hydrazine-based plating bath thanks to electroless plating technique. In particular, this paper highlights on the plating kinetics, film quality and efficiency notwithstanding. Moreover, the paper focuses on the gross evolution and development of the microstructure in the course of plating courtesy of X-ray photoelectron spectroscopy and X-ray diffraction. Conclusively, the study underscores the relationship between alloy formation and permeation efficiency (Tsuji 78).

Introduction

Thin film layer, as the name suggests, is a very slim layer of some material which thickness is measured in fractions as it can be from few nanometers (monolayer) to several micrometers. To this end, this technology finds its main applications in electronic semiconductor devices as well as in optical devices as optical coatings. A common example of a thin film application in our homes is a mirror which has a thin silvery coating that acts as a reflecting surface.

To improve the effectiveness of optical coatings, such as in antireflective otherwise AR coatings, multiple layers with different thicknesses as well as refractive indices are embedded as one. Akin to this technology, intervallic structure of intermittent thin films results in a material known as superlattice which limits electronic experience to two-dimension thanks to quantum confinement phenomenon. To date, advancement in technology is carried out on ferroelectric and ferromagnetic thin films to find applications in computer memory. In pharmaceutical field, thin film technology finds application courtesy of thin film drug delivery. Notably, thin film technology is used in the production of thin-film batteries as well as dye-sensitized solar cells (Tsuji 79).

The actual process of application of a thin film on a substrate is referred to as thin-film deposition. Basically, the term Thin is relative depending on the technique used in processing of a given layer (Williams and Carter, 11). Generally, most of these techniques vary their monolayer thickness within a bracket of a few folds of tens of a nanometer. Deposition of a monolayer of atoms is usually achieved courtesy of a molecular beam epitaxy which also finds application in the manufacture of packaging materials e.g. aluminum-coated PET films. Similar processes are sometimes used where thickness is not important: for instance, the purification of copper by electroplating (Crabtree 100). As such, deposition techniques can broadly be grouped into classes; physical and chemical deposition.

In view of the chemical deposition technique, a fluid precursor is transformed on contact with a solid surface, resulting in the formation of a thin layer. Since the liquid encloses the entire solid substrate, deposition occurs absolutely on the whole surface. Furthermore, depending on the precursor phases, this technique can further be categorized into five classes including: Planting, Chemical solution deposition (CSD), Spin coating, chemical vapor deposition (CVD) and, Atomic layer deposition (ALD). Specifically, while Planting relies on a solution of water and a salt of a metal as precursor, CSD relies on an organometallic powder in an organic solvent for the same (Vorotyntsev, Zinovyeva and Konev, 28). On the other hand, Spin coating relies on sol-gel precursor while CVD uses gas-phase precursor usually a halide. ALD uses gaseous precursors to achieve a thin layer (Crabtree 107).

In light of the physical deposition technique, a monolayer film of solid is deposited mechanically, thermodynamically or, electromechanically. To this end it is reputed that just like engineering materials which are held intact by relatively high energies, and with devoid of chemical energies, these techniques perform efficiently under low-pressure vapor environments. As such, it has been christened physical vapor deposition technique (PVD). Normally, the precursor is confined within an energetic, entropic niche, for the purpose of enhancing the atoms to leave its surface. On the recipient end a cooler surface absorbs the energy from the deposited atoms as they for a solid thin layer. The process is holistically done in a vacuum to achieve the best results. Basically, physical deposition relies on a thermal evaporator with molecular beam epitaxy (MBE), a more sophisticated type and the most efficient. A thermal evaporator uses an electric resistance heater to melt material and raise its vapor pressures to useful range (Morton 123). Other examples include: Electron beam evaporator, Sputtering, Pulsed laser deposition, Cathodic arc deposition (arc-PVD) and Electrohydrodynamic deposition.

With regard to this paper, we take a glimpse at the process of manufacture of Palladium-silver composite membrane thanks to electroless plating technique. Palladium-silver (Pd/Ag) membrane is vital in the production of environmental friendly fuel. Faced with quite a massive deposit of crude oil and, with the environmentalists outcry on zero-emission vehicles, the demand for hydrogen as an element for fuel purification is projected to skyrocket. To this end, production processes with regard to fuel products need to be advanced to enhance the effective utilization of hydrogen. Hydrogen selective membranes form the better part of intensive research in recent years (Cheng and Yeung, 127). Apart from its use as a fuel purifier, Pd/Ag membrane is useful in hydrogen elimination in process streams such as in dehydrogenation processes. With regard to the performance, palladium membranes are known for their higher selectivity degree (Cheng and Yeung, 128). Significantly, thin film palladium membranes enhance higher permeation flux.

Electroless plating aside, palladium membranes are also prepared using sputtering. CVD is later used to enhance the selective ability of this membrane. However, sputter coating has relatively low efficiency and is costly in preparation. In regard to membrane purity, pure palladium membranes are known to suffer from hydrogen embrittleness and are as well sensitive to trace elements (e.g. organohalides) which are present in process streams. This makes palladium composite membranes favorable in entirely all processes.

Specifically, this research focuses on the preparation of Pd/Ag membrane using the electroless plating method in a hydrazine-based plating bath. Considering the plating kinetics, film quality and plating efficiency are also studied. Also, a gross evolution of its microstructure is also analyzed courtesy of X-ray photoelectron spectroscopy and X-ray diffraction. As a result, the study reveals a correlation between allow development and permeation efficiency.

Experimental procedure

Palladium and silver co-deposition

In this procedure, the co-deposition of palladium and silver elements into solid thin layer within hydrazine-based solution was researched. The plating solution was composed of EDTA stabilized Pd-amine and Ag-amine metal complexes with hydrazine as a reducing agent (Cheng and Yeung, 128). To stabilize plating bath as well as the PH, excess ammonium hydroxide was used (Cheng and Yeung, 128). Vitally, care was taken to maintain the appropriated conditions for simultaneous, co-deposition lest consecutive deposition occur that would rather result to a bi-layer as opposed to the expected monolayer. The temperature conditions were maintained at 1K. A stimulated porous vycor tube of an area of about 5 cm² was then placed in the solution for a period of 1 hour. For the sake of structural analysis, the tube was cut along its cross-section for easy viewing.

The structure was observed using an SME, JEOL JSM-6300 scanner. The thickness, plating rates and characterization were also done. Moreover, the composition of the film layer was also determined.

Regarding the electroless plating kinetics, the amount of the substrate deposited was later on monitored over time to an accuracy of 0.01µg/cm². The concentrations were also varied systematically and growth monitored at a constant time of 10 minutes. Finally, with respect to alloy formation and membrane permeation, the gas permeation flow rates were later on determined using a bubble flow-meter and this was done at room temperature and pressure (Cheng and Yeung, 130).

Results/Analysis

A correlation was done for the plating parameters with respect to membrane permeation rates as well as film microstructure for the hydrazine-based palladium-silver plating solution.

In regard to palladium-silver co-deposition, the results below were obtained.

For the investigation of plating conditions, the following graphs were obtained:

Discussion and Conclusion

Figure 1 above shows a relationship between palladium and silver precursors co-deposition behaviors in hydrazine-based plating solution. The results as portrayed in the figure indicate that the degree of concentration of silver elements in the solution limits the deposition of palladium precursors. Consequently, this limits the overall plating efficiency of the metal precursors. A correlation between silver content in the membrane and its concentration in the plating solution indicates that even at lower concentrations of at most 5%, pure silver films are achievable. The figure also exhibits the average plating efficiency as having a low at about 40% Ag and has individual elements deposition rates higher than for the mixture (Cheng and Yeung, 131).

The reason for the above behavior has a bearing on the type of reaction that takes place among the three elements (hydrazine, Pd-amine, Ag-amine) in the plating bath solution. Basically, oxidation-reduction reaction is the reason behind the behavior. Hydrazine acts a reducer and as such it favors silver precursors as opposed to palladium consequently resulting in the initial deposition of the former limiting palladium deposition. This results in the formation of pure Ag-film as exhibited above. However, this can be reduced by initially seeding of palladium precursor in the solution or allowing the process to continue for a reasonably longer time (3 hrs.).

In regard to plating conditions, figure 2 (a) shows the effect of hydrazine concentration on the development Pd/Ag film. Basically, the graph portrays that at higher hydrazine to metal ratio one is in a better position to achieve pure palladium films even at higher Ag concentrations. At lower ammonium hydroxide concentrations (fig. 2 (b)) one is better placed to achieving more palladium deposition. As depicted by graph 2 (c) above more palladium concentration is achievable at higher temperatures as opposed to lower temperatures.

In view of the plating rates, the parameters were measured based on the membrane thickness thanks to electron micrograph scanning (Cheng and Yeung, 132). Both the average and the individual plating rates are shown in figures 3 (a, b and c) above. As demonstrated by graph 3 (a) above, the average plating rate went low with an increase in silver concentration in the hydrazine solution. However, the plating rate raised when hydrazine concentrations increased. The significant decrease in palladium plating with a negligible increase in silver precursor concentration as shown in figure 3 (b) confirms the fact that silver inhibits palladium deposition. Finally, figures 3 (c and b) demonstrates that as opposed to silver plating, increasing hydrazine concentration has a positive impact on the palladium plating. As such, as demonstrated in the figure above (3 (c)) at 20mM hydrazine concentration there is absolutely no Ag plating.

As for the microstructure analysis, figure 4 above demonstrates the different structural architecture of the film under different concentrations of silver with the temperature conditions and hydrazine concentration held constant. As such, figures 4 (a to d) show pictures of microstructure membranes having silver content of 100, 30, 12.5 and 5.5% resulting from plating solutions having silver concentrations of 50, 25, 12.5 and 6.2 respectively. These membranes exhibited continuous film with homogeneous grain size and they portrayed similar microstructure. In the contrary, membranes obtained from silver concentrations of 3.1 and 1.6% (4 (e and d)) had negligible silver content (0-1%), and they resulted in inconsistent microstructure. On drawing comparison between pure palladium microstructure membrane and Pd-Ag membrane it can be seen from the pictures that apart from inhibiting palladium plating, silver does also influence the structural architecture of the film.

In view of the membrane permeation efficiency (fig. 6) it is evident that for a common thickness the rate of hydrogen permeation for pure palladium membrane is dwarfed by Pd-Ag membrane. Pd-Ag membrane is superior by an order of between 1.4-1.7 times that of pure palladium membrane (Cheng and Yeung, 133).

Conclusion

In a conclusion, in this paper a glimpse into the knowledge about the science behind thin membranes was revisited. Eventually the paper narrowed down to the processing of Pd-Ag membrane where: a synopsis of the optimum conditions for simultaneous co-deposition of individual precursors in Pd-Ag membrane formation was determined. Moreover, the permeation efficiency in regard to membrane composition was also determined and to this end composite membrane outperformed pure membrane.

References

Cheng, Yi-Sheng and King Lun Yeung. Palladiumsilver composite membranes by electroless plating technique. Journal of Membrane Science. 158.1 (1999), 127-141. Elsevier. Web.

Crabtree, Robert. The Organometallic Chemistry of the Transition Metals. Hoboken, New Jersey: John Wiley and Sons, 2009. Print.

Hou, Kei and Rowling Hughes. Preparation of thin and highly stable Pd/Ag composite membranes and simulative analysis of transfer resistance for hydrogen separation. Journal of Membrane Science. 214.1 (2003): 43-44. Print.

Morton, Linda. Palladium sorbents remove contaminants from syngas, DOE Pulse. Denver: MacMurray, 1999. Print.

Tsuji, Jiro. Palladium reagents and catalysts: new perspectives for the 21st century. Hoboken, New Jersey: John Wiley and Sons, 2004. Print.

Vorotyntsev, Mikhail A., Veronica A. Zinovyeva and Dmitry V. Konev. Mechanisms of Electropolymerization and Redox Activity: Fundamental Aspects. Electropolymerization. Eds. Serge Cosnier and Arkady Karyakin. Germany: John Wiley & Sons, 2011. 27-47 Print

Williams, David B. and C. Barry Carter. Transmission Electron Microscopy: A Textbook for Materials Science. 2nd ed. New York: Springer, 2009. Print.

Broadly, archaeology scientifically studies prehistoric and historical human activities by recovering and analyzing material culture. As such, archaeologists excavate and describe past human-made objects ranging from simple tools such as stone daggers to complex structures as temples and cathedrals. On the other hand, classical archaeology has traditionally focused its attention on examining the civilizations of ancient Greece and Rome.

These investigations were prompted and inspired in renaissance Europe by the study of ancient Greek and Latin writings. In reviewing the extant texts, art, and other cultural artifacts from that early period, the conviction gradually developed that Greek and Roman culture constituted the entire western civilizations foundation. This paper seeks to show that the discipline of classical archeology is destined to flourish because it bears the very tenets on which archeology proper is built.

Intentionality is critical in any undertaking, academic or otherwise. Therefore, the academy should play a leading role in the social transformation to better human society at a global level. This paper argues that different disciplines are dealing with similar questions to no small extent, that technological advancement discourages excessive specialization. In line with the process of globalization, alternative interpretations of data need to be considered.

Classical archeology is built on robust archaeological theories which define and act as tenets of the broader discipline of archeology. It utilizes a combination of historic and prehistoric archeological techniques to study such varied evidence as settlement data, craft goods, environmental materials, and architectural remains (Willmes et al., 2020). As such, classical archeology fits within the world of archeology since other archeological and anthropological disciplines apply the same methods of practice. Additionally, the classical study of antiquity draws primarily from insight offered by ancient texts, mostly written in Latin and Greek (Carpino, 2019).

The combination of knowledge derived from the antique writings with ancient Greek and Roman artifacts offers an essential tool for learning other cultures and civilizations (Kajda et al., 2018). Its position within the broader field of archeology is further cemented by its massive contributions to the disciplines of social sciences and humanities.

As with any academic discipline, classical archaeology has its specific needs relating to the Mediterranean, which require specialized knowledge. However, as mentioned above, the various approaches differ according to the intentionality of the researchers. Classical archaeology was revered because it drew upon the concept of Hellenism. This involves the study and imitation of Greek culture meant that Europe obtained values from classical archaeology to pass these to their posterity, not only because they claimed Greek culture as the root of all European civilization, but also because it served European nationalism (Carpino, 2019).

Times have changed, and it is now known that individuals operate in a more pluralistic society. This pluralism is reflected in academies, where all disciplines are now treated equally. This aspect of classical archeology is guided by the Greek philosophy which also intends to be passed in its purest form from one generation to another. It remains valid today because core themes studied under classical archeology are still vital to the study of archeology proper.

Similar to archeology, classical archeology can be developed into an independent discourse. Historically, the former grew from antiquarianism in Europe around the 19th century to become a distinct discipline in its domain (Carpino, 2019). As a subsection of anthropology, the two broad elements are the historical and prehistorical study, each demanding different methodological analysis. Therefore, developing any of the two general groups into independent fields is ideally plausible.

An enormous amount of information is available as bequeathed to classical archeology enthusiasts; thus, the remaining task is an advancement to more extensive research. Its studys significance is relevant in understanding the present cultures since it concludes by examining recent traditions for comparison. Individuals must know their past norms and modes of reasoning to appreciate their present better.

Historical importance and classical archeologys role in the civilization of cultures attached to the study equally supports its growth. It covers both the pre and post-literate times of the past to build a general perspective on the chronological transition of traditions. However, it has less linguistic examination, unlike the former, which provides a suitable position for the advancement of other significant areas. Maintaining the datasets is relatively straightforward because of the global quality, comparative potential, and integrative possibilities attached to it. The development can take any form since it has elements from different fields such as science and humanities.

Additionally, the porous boundaries which prompt interaction with other areas of specialties promote its independence capacity. Because of the contributions to the understanding of society, it can be developed through interdisciplinary examination. Therefore, classical archeology can remain as an independent discipline in order to maintain and sharpen its focus on the Mediterranean antiquity. Its combination with mainstream anthropology would obscure the vital relevance it poses in terms of archeological theory. Nevertheless, considering the future of archeology as part of anthropology would improve data collection techniques and analysis since anthropology is better at studying people and communities.

Classical archeology has a future with or without the primary actors because of its broad nature. It covers the concept of area studies focusing on a plethora of topics such as kinship, minorities, language, and religion. Although they can easily cause intellectual blindness, area studies are useful, which restricts anthropological imagination and analysis (MacMullen, 2020). The current main actors limit the rate of the transition process; thus, there is a need for new exuberant members.

For instance, researchers who have gone beyond the boundaries have been censored. Therefore, a change in the influential archeologists can lead to the growth of area scholars who can integrate comparative findings from other fields. In the establishment of colonialism in Africa, ethnographic studies were seen as important aspects of the development of the colonies (Montecchi & Mercuri, 2018). When these states achieved their independence, the roles and approaches changed where each ethnographer focused on their people.

There are remarkable differences in the modes of ethnographic deductions across diverse cultures. The anthropologist thus needs to develop self-awareness because of the rising criticism. Scholars outside the Anglo-American world continually identify the biases of the west in their studies (Arponen, 2019). In contrast, those in India, the Middle East, and Pakistan point out Americas difficulties in appreciating other traditions. Foreign schools play an essential role in comparing data from different areas and periods in time (Kearns, 2017). As such, they provide essential service from the Mediterranean perspective, where every culture is appreciated. They somewhat disregard the colonialist agenda of ethnography while promoting a comparative approach.

Classical archaeology will need to adapt by deepening its cooperation with other disciplines to survive. The study of cultural artifacts has always been a collaborative process. The need for collaboration will only intensify as advancing technology make available a wide variety of new tools and, therefore, new approaches (Carruthers & Van Damme, 2017). This partnership should be welcomed because collaboration with other disciplines will help classical archaeology to overcome its limitations.

Furthermore, it is not a question of giving up its identity but a redefinition and broadening of its scope. It is, therefore, fair and to open it up to other models and points of view. European societies have drawn inspiration and motivation from Greek and Roman antiquity (MacMullen, 2020). They have also used that past to validate their present, and that authentication has had positive and negative aspects. Classical archaeology has no option but to broaden its perspective to accommodate a more pluralistic view and minimize the misuse of the past.

There is always a time lag between changes in societies and the educational systems alterations in response to those societal transitions. That is why Bertrand Russel wrote that what students are taught in schools is at least half a century outdated (Montecchi & Mercuri, 2018). A paradigm shift is necessary in order to allow for a more collaborative approach in teaching and hiring. This radical change will provide for a broader and more culturally diverse understanding of societal development. It shall also enable a better appreciation of available cultural artifacts. In short, classical archaeology is facing an identity crisis in a fast-changing world.

To conclude, intentionality is critical in any undertaking, academic or otherwise. It is crucial that the academy play a leading role in social transformation for the betterment of human society at a global level. Classical archaeology should, therefore, adapt in order to retain its relevance. It should adopt a more integrative approach as this is a sure way to increase the understanding of ancient Greece and Rome. The new integrative approach will also allow classical archaeology to use its data sets and develop ideas that have application in other disciplines.

Annotated Bibliography

Carpino, A. A. (2019). The diversity of classical archaeology: Edited by Achim Lichtenberger and Rubina Raja (Studies in Classical Archaeology 1). Etruscan and Italic Studies, 22(1-2), 171-173.

The text was useful in familiarizing with the books various concepts. However, I did not obtain all the required information for the assignment from the source single handedly. Moreover, it was aimed to analyze recent research to show the rejuvenated vitality in the field. The book has a brief introduction with five sections. The sections include learning from the past, breaking up disciplines, unlocking time and space, art and material culture in the making, and perceptions. The writing is insightful in examining the viability of archeology to stand on its own as an independent discipline.

Montecchi, M. C., & Mercuri, A. M. (2018). When palynology meets classical archaeology: The Roman and medieval landscapes at the Villa del Casale di Piazza Armerina, UNESCO site in Sicily. Archaeological and Anthropological Sciences, 10(4), 743-757.

The research is relevant to this paper because of the new way of understanding the present landscape through the past broadening classical archeology. The text involves an analysis of cooperative objects with national and local institutions in central Sicily. Moreover, the discovery of vitis pollen grains within the Roman site provided more in-depth insight into the landscape during the then periods. It is plausible to conclude that the area was open, treeless with hilly vegetation.

Willmes, C., NiedzióBka, K., Serbe, B., Grimm, S. B., Groß, D., Miebach, A. & Mateos, A. (2020). State of the art in paleoenvironment mapping for modeling applications in archeologySummary, conclusions, and future directions from the PaleoMaps Workshop. Quaternary 2020, 3(2), 13. Web.

The text presents contributions, discussions, and outcomes derived from the Paleomaps Workshop 2019. The workshops primary aim included providing an overview of theories and methodologies used to integrate paleoenvironmental information into human-environment interaction. As such, it builds from the current modeling applications to design better ways. The report describes an analysis of the presented papers and the protocols following thereafter. It provides fundamental literature that future research will build on. It is relevant to this paper because of the background information it provides that supports the legitimacy of developing classical Archeology into a discipline.

Kajda, K., Marx, A., Wright, H., Richards, J., Marciniak, A., Rossenbach, K. S., Michal P., Monique H., Krijn B., Maria P. G., Felipe C., David B., Anita S., Kostantinos K., Kostantinos K., Eleftheria T., Friedrich L., Mayssoun I. & Criado-Boado, F. (2018). Archaeology, heritage, and social value: Public perspectives on European archaeology. European Journal of Archaeology, 21(1), 96-117.

The article helped me understand the general perception of archeology and how the public view is influenced across Europe. The discussions were focused on the significance of the contemporary archeological study. The first area is archeologys image and how the general populace defines it. In the second phase, it considers the values that archeology offers and social expectations. The text supports my ideology that there is remarkable European thought that it should work alongside other disciplines. Cultural heritage management engagement requires interaction with other discourses, which is more readily achieved by advancing classical archeology.

Kearns, C. (2017). Mediterranean archeology and environmental histories in the spotlight of the Anthropocene. History Compass, 15(10), e12371.

The text recognizes the rapid technological growth, which continually advances scientific and humanistic research, especially on anthropogenic effects on earth systems. The systems include features such as climate, which mainly result in a controversial proposal that we live in an Anthropocene epoch. It provides a broader view of how humans have been the forces of global change. Besides, it analyzes the archeologists and historians conception of social and environmental change in Mediterranean antiquity. The revolution experienced in the scientific world is useful in advancing historical archeology.

MacMullen, R. (2020). Top Scholars in Classical and Late Antiquity. History of Classical Scholarship, 2, 105-114.

The article offers a recent move towards analysis and bibliographic evidence to examine ancient history. The article was useful for this research because of the background information it provided. The collection of past works offers substantial proof that the existing literature is comprehensive enough to support historical archeology as an autonomous discipline. However, the text overly focuses on criticism of Walter Scheidel and Nathan Pilkitong, who researched the impact of previous iconic scholars.

Carruthers, W., & Van Damme, S. (2017). Disassembling archeology, reassembling the modern world. History of Science, 55(3), 255-272.

The text provides significant findings on the discussion of the applicability of archeologys history to science. Besides, it outlines the papers contained within its unique issue as evidence of the relevance of the two discourses. The historical, thematic assessments of archeology overlaps with those of science and its regimes in antiquarianism. It also discusses the issues relating to the professionalization of the archeological public, colonialism, empire, and circulation of knowledge. Other inclusive data is the enriching enlightenment on scientific ethics, museums, material cultures. The information from this article was essential in explaining the validity of retaining classical archeology as a disciple due to its privileged position.

Arponen, V. P. J., Grimm, S., Käppel, L., Ott, K., Thalheim, B., Kropp, Y.,& & Ribeiro, A. (2019). Between natural and human sciences: On the role and character of theory in socio-environmental archeology. The Holocene, 29(10), 1671-1676.

It reflects on the skepticism of most scholars on theory in archeology because of the new technological inventions. The article further analyzes the interrelationship between scientific advancements and theoretical stands within socio-environmental archeology. As such, there is a critical need to integrate the two to have versions of each other in a unified whole. The conceptual discussions of archeology such as evolutionism would serve more than a dismissal of one of the essential elements. The text is thus essential in proving the autonomy of classical archeology. The new methodologies and techniques to be applied are likely to further broaden the field with new members and existing ones.

References

Arponen, V. P. J., Grimm, S., Käppel, L., Ott, K., Thalheim, B., Kropp, Y., Konrad Ott, k., Thalheim, B., Kropp, Y., Kittig, K., , Brinkmann, J., & Ribeiro, A. (2019). Between natural and human sciences: On the role and character of theory in socio-environmental archeology. The Holocene, 29(10), 16711676.

Carpino, A. A. (2019). The diversity of classical archaeology. Etruscan and Italic Studies, 22(1-2), 171173. Web.

Carruthers, W., & Van Damme, S. (2017). Disassembling archeology, reassembling the modern world. History of Science, 55(3), 255272.

Kajda, K., Marx, A., Wright, H., Richards, J., Marciniak, A., Rossenbach, K. S., Marciniak, a., Rossenbach, K.S., Pawleta, M., Van den Dries, H, M., Boom, K., Guermandi, M, P., Criado-Boado, F., Barreiro, D., Synnestvedt, A., Kotsakis, K., Kasvikis, K., Theodoroudi, E., Luth, F., Issa, M.,& Frase, I. (2018). Archaeology, heritage, and social value: Public perspectives on European archaeology. European Journal of Archaeology, 21(1), 96117.

Kearns, C. (2017). Mediterranean archeology and environmental histories in the spotlight of the Anthropocene. History Compass, 15(10), 5, (98-101).

MacMullen, R. (2020). Top scholars in classical and late antiquity. History of Classical scholarship, 2, 105114.

Montecchi, M. C., & Mercuri, A. M. (2018). When palynology meets classical archaeology: The Roman and medieval landscapes at the Villa del Casale di Piazza Armerina, UNESCO site in Sicily. Archaeological and Anthropological Sciences, 10(4), 743-757.

Willmes, C., NiedzióBka, K., Serbe, B., Grimm, S. B., Groß, D., Miebach, A., Miebach, A., Henselowsky, F., Gamisch, A., Rostami, M., Mateos, A., Rodríguez, J., Limberg, H., Schmidt, I., Muller, M., Hölzchen, E., Holthausen, M., Klein, K., Wegener, C & Mateos, A. (2020). State of the art in paleoenvironment mapping for modeling applications in archeologySummary, conclusions, and future directions from the PaleoMaps Workshop. Quaternary 2020, 3(2), 13. Web.

Human social and genetic research seeks to understand the occurrence and magnitude of environmental (nurture) and genetic (nature) effects on peoples uniqueness, cognitive capacity, behavior, and interests. Adoption and twin research affirm that behavioral attributes are principally heritable (In Colombia par. 2). However, attempts to establish genes that influence behavior have generated minimal confirmed connections or relations. Behavioral genetics studies depict the significance of environmental aspects. In contrast with most behavioral scientists anticipations, pertinent environmental facets seem to be the ones that the twins reared together do not share. Studies of identical twins who have been raised in different regions fascinate not just researchers but also the public. Each pair of identical twins share 100% of their genetic characteristics (In Colombia par. 4). Research on identical twins who have been reared apart shows that half of their divergences in personality and pietism are genetically established. Additionally, the surrounding environment determines only about 25% of variations in attributes such as I.Q.

Psychologists have sought to clearly understand the impact of nurture and nature on human attributes for many decades. Following the scientific fields realization that genes and environment have an essential role in human development, emphasis has shifted to the determination of the more influential one. Nurture many have an even more significant influence on human development and characteristics than originally alleged (In Colombia par. 9). In summary, anchored in numerous studies, it has been confirmed that a persons behavior and traits are influenced by both nurture and nature. Although genetic disposition is essentially valuable in establishing human characteristics, there is always the necessity of an environmental prompt that makes the attribute to become visible in a person.

Work Cited

In Colombia, a Curious Case of Mixed-Up Twins and Brotherly Love. Fordham News, 2018, Web.

The central dataset picked up by satellite geodesy is most useful in the geoidal anomalies than in gravity anomalies form. One noted feature of the earths field of gravity is the level of dominance in the low degree, long wavelength harmonics, and a way of viewing the significance of a low degree harmonics is by geoidal anomalies. Normally, a geoid is so sensitive to deep mass dispersions than its gravitation. According to Crough, in Chase (1989), a geoid will exhibit a pace offset throughout the boundaries of isostatically evened out characteristics like oceanic or continental margins, in a level earth estimate. Possibly, the first attempt of geoidal anomalies interpretation in the momentous world was proposed by Runcorn in the year 1964. He suggested that it was possible to convert geopotential anomalies into diagrams of small lithospheric stress by acquiring the Newtonian streamline flow and handling the geosphere as a rigid shell. Nonetheless, a substantial difficulty to this kind of approach is that there were various origins of geoidal anomalies hence could be ascribed to only a convective pattern (Chase 2-5).

Some other studies did ascribe the low degree harmonics to the undulating boundaries of the mantle. In the modeling of geoidal signature of merging plates boundary, it was found that subduction slabs were regionally counterbalanced and that they were not by a long sight the only significant feature that caused the long wave length waves within the geoid. The most noteworthy thing about the earths field of gravity was that the biggest and greatest amplitude anomalies contained an almost invisible relationship to the natural process conveyed at the lands outermost level in the plate tectonic theory. Some tectonic characteristics such as oceanic hotspots, more than plates, bore a mutual relationship with the long wavelength geoid (Chase 6-7).

On the contrary, in short wavelengths, geoid anomalies were utile in restricting several features of the structure of the lithosphere. Isostatic variances betwixt the earths land masses and seas did not have to go unusually deep as thermal structures within the mid oceanic ridges could be measured from the geoid. In topographic points where long wavelength anomalies of deep origins controlled the contours, then old continental crusts were apparently marked by some positive geoid relief. Chase (1985) noted that, a study done by Harxby and Turcotte in 1978 helped to indicate that for an elementary Isostatic thermal framework of rising mid-oceanic ridge crests, the geoidal anomaly must be a linear function of crusts age (Chase 16).

In mid plate convections, it was discovered that hotspots upwelling was not enough by itself, to provide the high temperatures at the base of the oceanic lithosphere, instead a small convection was needed at the upper mantle. However, gravitational and geoidal anomalies could not entirely resolve the issue of small convection; a bathymetry in some kind of residual depth anomaly was to be put into consideration (Chase 18). Additionally, heat conductivity within the earth was exceedingly slack such that the conductivity model for heating a slab underrated the mass excesses. As the slab continued to warm, the encompassing mantle became cold leading into a cold area that was difficult to break up (Chase 7-8).

The use of geoids to represent the earths field of gravity has proved to be a productive instrument for looking into different matters pertaining to geology some of which include subduction slab compensation and geoidal anomalies around zones of geological fault. In order to ensure full development of geoidal field possibility, satellite enabled geoidal details and resolutions should be accomplished across the continental regions.

Works Cited

Chase, Clement G. The Geological Significance of the Geoid. Annual Review Earth Planet (1985): 97-117. Print.

Sampling distortion happens when some people are more likely than others to be chosen systematically in a survey. In the medical profession, it is also known as ascertainment bias. Since sampling bias jeopardizes external validity, especially population validity, findings are restricted in their generalizability. In other words, results from skewed studies can only be extrapolated to populations that share the samples characteristics. During an interview, sampling differences arise when the selection is chosen to be less likely than other people, suggesting that the whole population is not portrayed and that the findings are partial and inaccurate. Notably, this is a condition referred to as sampling bias (Komori et al., 2020). Such a survey will result in a partial sample with limited findings. Discrimination in the absence of response is if a research participant fails to answer or leaves those questions unanswered. If a person looks over the questionnaire, this will occur. If the results of a particular study are changed, they will not be considered answerable if their responses are presented.

Such a condition is referred to as a non-response biastwo forms of non-response usually exist-objects and units. In non-response bias, an item is not answered when a survey questionnaire does not address any questions. Non-response units arise when a random sample cannot be reached or refuses to take part in an inquiry. Several strategies may be used to improve the response rate and reduce non-response, including conducting surveys. The best way of surveying people, ideally after an experiment, will be via personal interviews. The level of responses will also increase with a face-to-face survey. In all, to educate participants about the meaning of the survey and to avoid bias questions, it is necessary to have a correct communication strategy (Smironva et al., 2020). The data collection process, for example, by mail, personal interview or phone interview, electronic reporting, the Internet, or a combination of methods, should be monitored at the time of year.

References

Komori, O., Eguchi, S., Saigusa, Y., Kusumoto, B., & Kubota, Y. (2020). Sampling bias correction in species distribution models by quasi-linear Poisson point process. Ecological Informatics, 55, 101015.

Smironva, E., Kiatkawsin, K., Lee, S. K., Kim, J., & Lee, C. H. (2020). Self-selection and non-response biases in customers hotel ratings  A comparison of online and offline ratings. Current Issues in Tourism, 23(10), 1191-1204.