User:Shalom Yechiel/Wikipedia got me into graduate school

My preparation for graduate school is enhanced by two extracurricular achievements. I synthesized and studied a new polymer material in 2005, and I presented my results in a national conference in 2006. More recently, I have written and edited chemistry articles for the world’s most popular online encyclopedia. In graduate school, I plan to study nanomaterials, including microfluidics, semiconductors, and catalysts.

Polymer research

I did research at Wellesley College in summer 2005 with funding from the National Science Foundation Research Experiences for Undergraduates (NSF-REU) program. My mentor, Dr. Nolan Flynn, and I studied phase transitions and other properties of crosslinked w:poly(N-isopropylacrylamide) (PNIPAm) hydrogels containing metal nanostructures.

PNIPAm was first synthesized in the 1950s. It forms a three-dimensional hydrogel when crosslinked with N,N’-methylene-bis-acrylamide (MBAm) or N,N’-cystamine-bis-acrylamide (CBAm). When heated in water above 33°C, it undergoes a reversible phase transition from a swollen hydrated state to a shrunken dehydrated state, losing about 90% of its mass. Since PNIPAm expels its liquid contents at a temperature near that of the human body, PNIPAm has been investigated by Japanese researchers for possible applications in controlled drug delivery.

I created PNIPAm hydrogels crosslinked with MBAm and/or CBAm, and added metal (Au, Ag, Pt, Pd, Ru, Cu, Ni) nanostructures in situ. Dr. Flynn already knew that addition of gold in situ to a hydrogel crosslinked with CBAm causes significant changes. The room-temperature swelling increases by an order of magnitude, and the phase transition temperature rises above 40°C.

I found that addition of other metal nanostructures produces no significant effect except for a change in color. I used UV-vis spectroscopy to quantify the changes in color, and IR spectroscopy to test for changes in the chemical structure of the hydrogels. Based on a comparison of IR spectra, Dr. Flynn and I believe that gold catalyzes a reaction on the disulfide bridge of CBAm, but other metals do not catalyze this reaction.

Dr. Flynn and I presented our results at two poster sessions at the 231st American Chemical Society (ACS) National Meeting in Atlanta in March 2006.

Writing for Wikipedia

I write and edit chemistry articles on Wikipedia and Wikibooks using the pseudonym “Shalom”. Notable articles I have authored include ladderane, JAICI, spacial quantization, and Lindemann mechanism. I discuss each of these articles next.

w:Ladderane is an organic molecule containing two or more fused rings of cyclobutane. I was inspired to write this article after I heard a lecture at the 234th American Chemical Society National Meeting in Boston last August, in a symposium to honor the Nobel Prize winner Roald Hoffmann for his 70th birthday. Despite the ring strain, long chains of ladderane have been synthesized, and were recently discovered in living organisms.

The w:Japan Association for International Chemical Information (JAICI) has collaborated with the Chemical Abstracts Service (CAS) to translate scientific abstracts from Japanese to English and vice versa. Hideaki Chihara, who founded JAICI in 1971, presented his organization’s accomplishments to a standing ovation at the 234th ACS conference, in a symposium to honor the 100th anniversary of CAS.

w:Spacial quantization is the quantization of angular momentum vectors based on the selection rules for the quantum numbers l and ml. Only the length and the z-component of angular momentum can be known simultaneously, but all values of the x- and y-components are allowed. Angular momentum vectors can be represented as a small number of cones, where the variable x- and y-components correspond to all points on the circumference of the cone’s base. I used my quantum chemistry textbook to write this article.

The w:Lindemann mechanism has been used to model gas phase decompositions, such as the reaction N2O5 → NO₂ + NO₃. I wrote this article after studying reaction kinetics to prepare for the GRE. It was displayed on the “Did you know?” section of Wikipedia’s Main Page.

Graduate school and beyond

In graduate school, I plan to study nanomaterials, including microfluidics, semiconductors, and catalysts. These nanomaterials will facilitate the invention and distribution of new technology for the 21st century.

Microfluidic devices are systems for manipulating fluids in micrometer-scale channels and wells,” according to a recent C&EN article. Their diverse applications include modeling of lungs and blood vessels, inkjet printing, and fuel cells.

Semiconductors are fundamental to modern electronics, from computers to cell phones to digital audio players. The continuing optimization of computer systems will require improvements in the precise fabrication of composite metal dopants.

Inorganic catalysts have been essential to facilitate organic reactions such as the synthesis of ammonia (using the Haber process) and the polymerization of polyethylene and polypropylene (using Ziegler-Natta catalysts). Today, instead of focusing on mass production of common materials, many scientists are searching for catalysts that facilitate regioselective and stereoselective bond formation in complex molecules.

My curiosity extends to all branches of chemistry and many other fields of knowledge. A common thread in all my learning is my desire to communicate my knowledge to others and to help the community accomplish tasks far beyond my own limited abilities. My polymer research in 2005 formed a link in the chain of Dr. Flynn’s research group at Wellesley College. Dr. Flynn himself collaborates with researchers at other universities to build a collection of literature from around the globe. Similarly, my contributions to Wikipedia integrate my knowledge into a large learning community.

I look forward to teaching chemistry as part of the graduate school program. I currently teach an after-school chess class, and I taught Judaic studies in a summer camp. After I earn a Ph.D., I will look for a full-time academic teaching position, or I will apply my skills to industrial R&D.