chemist

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I think that everyone should take a look at these gorgeous drawings representing Women and their accomplishements in Science, by Rachel Ignotofksy - a fantastic illustrator and graphic designer. She also has a lil Etsy shop where she sells her prints here!!!

“When the main rockets go off you may not know where you’re going, but you know you’re going somewhere”.

- Anna L. Fisher, Chemist, Doctor and Astronaut. A true renaissance woman.

(Image via National flight academy,Information via NASA)

Dedicating to all ‪#‎Scientist‬ ; ‪#‎PhD‬ holders ‪#‎Research‬ scholars in all over the world !!!

Felt alone day and night lost many relatives and friends not to mean we dont like those but , We purely love our subjects little more than all…

lets celebrate every day and never give up !!!!!!!!!

Cheap and abundant chemical outperforms precious metals as a catalyst

A team of Caltech chemists has discovered a method for producing a group of silicon-containing organic chemicals without relying on expensive precious metal catalysts. Instead, the new technique uses as a catalyst a cheap, abundant chemical that is commonly found in chemistry labs around the world—potassium tert-butoxide—to help create a host of products ranging from new medicines to advanced materials. And it turns out that the potassium salt is more effective than state-of-the-art precious metal complexes at running very challenging chemical reactions.

“We have shown for the first time that you can efficiently make carbon-silicon bonds with a safe and inexpensive catalyst based on potassium rather than ultrarare precious metals like platinum, palladium, and iridium,” says Anton Toutov, a graduate student working in the laboratory of Bob Grubbs, Caltech’s Victor and Elizabeth Atkins Professor of Chemistry. “We’re very excited because this new method is not only ‘greener’ and more efficient, but it is also thousands of times less expensive than what’s currently out there for making useful chemical building blocks. This is a technology that the chemical industry could readily adopt.”

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Physics envy.

In science, the term physics envy is used to criticize a tendency (perceived or real) of softer sciences and liberal arts to try to obtain mathematical expressions of their fundamental concepts, as an attempt to move them closer to harder sciences, particularly physics.

A physicist’s response.

“To those who do not know mathematics it is difficult to get across a real feeling as to the beauty, the deepest beauty, of nature … If you want to learn about nature, to appreciate nature, it is necessary to understand the language that she speaks in.”

-Richard Feynman,

Rosalind Franklin was an English chemist and X-ray crystallographer who made contributions to the understanding of the fine molecular structures of DNA, RNA, viruses, coal, and graphite.

Franklin attended one of the few girls’ schools in London that taught physics and chemistry, she excelled at science and at 15 decided she would become a scientist. Her father was against higher education for women and had wanted her to become a social worker but he relented. She graduated in Natural Sciences Tripos from Newnham College, Cambridge in 1941. Franklin then held a graduate fellowship for a year, joining the University of Cambridge physical chemistry laboratory under Ronald George Wreyford Norrish. His lack of enthusiasm disappointed her and she quit in 1942 to work for the British Coal Utilization Research Association (BCURA). Franklin’s studies of carbon and graphite microstructures became the basis of her docorate in phsyical chemistry, earning her a PhD in 1945 from Cambridge University.

Franklin then spent three years in Paris at the Laboratoire Central des Services Chimiques de L'Etat. She worked with crystallographer Jacques Mering who taught her X-ray diffraction techniques. In 1951 she returned to England to work as a research associate in John Randall’s laboratory in the biophyscis unit at King’s College, London. Randall gave Franklin responsibilty for a DNA project, she used her expertise and X-ray diffraction techniques (mostly of proteins and lipids in solution) to study DNA fibres. During her research, fellow scientist Maurice Wilkins returned to the lab and assumed that she was a technical assistant, causing a rift between them that was never repaired. His assumption was unsurprising due to the institutional sexism at the university, women were not allowed in the university dining rooms, and after hours Franklin’s colleagues went to men-only pubs.

Franklin and her student Raymond Gosling came close to solving the structure of DNA. J. D. Bernal called her X-ray photographs of DNA, “the most beautiful X-ray photographs of any substance ever taken.” The pictures of DNA showed that there were two forms, a dry “A” form and a wet “B” form. One of their X-ray diffraction pictures of the “B” form of DNA, known as Photograph 51, became famous as critical evidence in identifying the structure of DNA. The photo was acquired through 100 hours of X-ray exposure from a machine Franklin herself had refined. In 1951 Franklin gave a lecture presenting these findings. She was the first to discover and formulate these facts, which constitute the basis for all later attempts to build a model of the molecule.

Franklin’s tense relationship with Wilkins may have been the cause of him disclosing Photo 51 to competing scientist James Watson, who was working on his own DNA model with Francis Crick at Cambridge. The photograph alone was not enough, precise observations from X-ray crystallography were also needed to be able to discover more about the structure of DNA. These were given to the two scientists by Crick’s thesis advisor, Max Perutz in the form of a brief report Franklin had written. They used the report to inform their calculations and allowed them to discover that the molecule was in two matching parts, running in opposite directions.

Franklin had intitially found it difficult to interpret her results but had come to the conclusion that DNA had a double helix structure, with component nucleotides or bases on each strand that were complementary, enabling the molecule to replicate. She noted that there was an infinite variety of nucleotide sequences would be possible to explain the biological specificity of DNA’. She was unable to prove her point mathematically before Watson and Crick allegedly beat her to it, creating a physical model of their findings.

In April 1953, the scientific journal Nature published three back-to-back articles on the structure of DNA. The first was theoretical, written by Watson and Crick, this was followed by two papers, one by Maurice Wilkins and two colleagues and the other by Franklin and Gosling. They appeared to support Watson and Crick’s findings, rather than being appropriately credited for their contribution to the discovery. In 1962, Watson, Crick and Wilkins recieved a Nobel Prize for their work on DNA, Franklin was not eligible as the prize is not awarded post-humously.

Franklin left King’s College in March 1953, promising that she would not work on DNA. She led her own research team at Birkbeck College, completing pioneering work on the molecular structures of viruses, including tobacco mosaic virus and the polio virus. Franklin published 17 papers on viruses, and her group laid the foundations for structural virology.

In 1956 Franklin was diagnosed with ovarian cancer, although she had three operations and experimental chemotherapy she continued to work up until several weeks before her death at 37 on April 16th 1958.

Sources here, here, here, here and here

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Math and Science Week!

aseantoo submitted to medievalpoc:

I really love watching Drunk History, so I’m really glad they uploaded their entire segment on the African-American chemist Percy Julian (1899-1975). Not sure what your feelings are about the show.

I’m actually not a huge fan of the show for various reasons, but this episode is an absolute must-watch. O.M.G.