chemistry (5)

Dr. Bettye Washington Greene...

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Science History Institute: Dr. Bettye Washington Greene

 


Topics: African Americans, Chemistry, Diversity in Science, Nanotechnology, Women in Science

 

American Chemical Society: Nanotechnology



Bettye Greene was born on March 20, 1935 in Fort Worth, Texas and earned her B.S. from the Tuskegee Institute in 1955 and her Ph.D. from Wayne State University in 1962, studying under Wilfred Heller. She began working for Dow in 1965 in the E.C. Britton Lab, where she specialized in Latex products. According to her former colleague, Rudolph Lindsey, Dr. Greene served as a Consultant on Polymers issues in the Saran Research Laboratory and the Styrene Butadiene (SB) Latex group often utilized her expertise and knowledge. In 1970, Dr. Greene was promoted to the position of senior research chemist. She was subsequently promoted to the position of senior research specialist in 1975.

In addition to her work at Dow, Bettye Greene was active in community service in Midland and was a founding member of the Delta Sigma Theta Sorority, Inc., a national service group for African-American women (actually, more likely one of the alumni chapters). Greene retired from Dow in 1990 and passed away in Midland on June 16, 1995. [1]

 

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Her doctoral dissertation, "Determination of particle size distributions in emulsions by light scattering" was published in 1965.

Patents:

4968740: Latex-based adhesive prepared by emulsion polymerization
4609434: Composite sheet prepared with stable latexes containing phosphorus surface groups
4506057: Stable latexes containing phosphorus surface groups [2]


Spouse: Veteran Air Force Captain William Miller Greene in 1955, she attended Wayne State University in Detroit, where she earned her Ph.D. in physical chemistry working with Wilfred Heller.

Children: Willetta Greene Johnson, Victor M. Greene; Lisa Kianne Greene [2]

 

1. Science History Institute Digital Collections: Dr. Bettye Washington Greene
2. Wikipedia/Bettye_Washington_Greene

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No Planet B...

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BENEDETTO CRISTOFANI/SALZMANART

 

Topics: Chemistry, Climate Change, Economy, Global Warming, Green Tech, Jobs


This week will be historic. In over 150 countries, people are stepping up to support young climate strikers and demand an end to the age of fossil fuels. The climate crisis won’t wait, so neither will we. Source: Global Climate Strike dot net

As with the Parkland demonstrations on mass shootings, young people are leading us - actually, PULLING us over the line to DO something about both important matters.
 
This is not about being "woke": it's about being aware. The extreme avarice causing this societal division and economic stratification could be just the petard humanity hoists itself with* to extinction. I'm glad you all know that, because old, fossilized wealthy (men mostly) can't see beyond the next quarter; that their wealth also falls to dust if the planet fails beneath them. As far as the youth, this is THEIR planet as those above septuagenarians and octogenarians are exiting it. The very least adults can do is use our ashes to fertilize trees for more oxygen (my personal plans). We should leave something for them to live out their lives and dreams. To do less is the height of arrogance, self-destruction and egomania.

Shakespeare's phrase, *"hoist with his own petard", is an idiom that means "to be harmed by one's own plan to harm someone else" or "to fall into one's own trap", implying that one could be lifted (blown) upward by one's own bomb, or in other words, be foiled by one's own plan. Source: Wikipedia
 

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Black, gooey, greasy oil is the starting material for more than just transportation fuel. It's also the source of dozens of petrochemicals that companies transform into versatile and valued materials for modern life: gleaming paints, tough and moldable plastics, pesticides, and detergents. Industrial processes produce something like beauty out of the ooze. By breaking the hydrocarbons in oil and natural gas into simpler compounds and then assembling those building blocks, scientists long ago learned to construct molecules of exquisite complexity.

Fossil fuels aren't just the feedstock for those reactions; they also provide the heat and pressure that drive them. As a result, industrial chemistry's use of petroleum accounts for 14% of all greenhouse gas emissions. Now, growing numbers of scientists and, more important, companies think the same final compounds could be made by harnessing renewable energy instead of digging up and rearranging hydrocarbons and spewing waste carbon dioxide (CO2) into the air. First, renewable electricity would split abundant molecules such as CO2, water, oxygen (O2), and nitrogen into reactive fragments. Then, more renewable electricity would help stitch those chemical pieces together to create the products that modern society relies on and is unlikely to give up.

Chemists in academia, at startups, and even at industrial giants are testing processes—even prototype plants—that use solar and wind energy, plus air and water, as feedstocks. "We're turning electrons into chemicals," says Nicholas Flanders, CEO of one contender, a startup called Opus 12. The company, located in a low-slung office park in Berkeley, has designed a washing machine–size device that uses electricity to convert water and CO2 from the air into fuels and other molecules, with no need for oil. At the other end of the commercial scale is Siemens, the manufacturing conglomerate based in Munich, Germany. That company is selling large-scale electrolyzers that use electricity to split water into O2 and hydrogen (H2), which can serve as a fuel or chemical feedstock. Even petroleum companies such as Shell and Chevron are looking for ways to turn renewable power into fuels.

Changing the lifeblood of industrial chemistry from fossil fuels to renewable electricity "will not happen in 1 to 2 years," says Maximilian Fleischer, chief expert in energy technology at Siemens. Renewable energy is still too scarce and intermittent for now. However, he adds, "It's a general trend that is accepted by everybody" in the chemical industry.

I repeat:
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Tee Public: I'm going to buy this shirt

 

Can the world make the chemicals it needs without oil?
Robert F. Service, Science Magazine

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Boiling Superconductivity...

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Under pressure: calculated structure of lithium magnesium hydride. Lithium atoms appear in green, magnesium in blue and hydrogen in red. (Courtesy: Ying Sun et al/Phys. Rev. Lett.)

 

Topics: Chemistry, Materials Science, Nanotechnology, Superconductors


A material that remains a superconductor when heated to the boiling point of water has been predicted by physicists in China. Hanyu Liu, Yanming Ma and colleagues at Jilin University have calculated that lithium magnesium hydride will superconduct at temperatures as high as 473 K (200 °C).

The catch is that the hydrogen-rich material must be crushed at 250 GPa, which is on par with pressures at the center of the Earth. While such a pressure could be achieved in the lab, it would be very difficult to perform an experiment to verify the prediction. The team’s research could, however, lead to the discovery of more practical high-temperature superconductors.

Superconductors are materials that, when cooled below a critical temperature, will conduct electricity with zero resistance. Most superconductors need to be chilled to very low temperatures, so the holy grail of superconductivity research is to find a substance that will superconduct at room temperature. This would result in lossless electricity transmission and boost technologies that rely on the generation or detection of magnetic fields.

 

Superconductivity at the boiling temperature of water is possible, say physicists
Hamish Johnston, Physics World

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Nanocones...

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A carbon nanocone includes nitrogen atoms around the periphery to improve the material’s solubility. Carbon atoms are shown in gray; hydrogen in white; nitrogen in blue; and oxygen in red.

 

Topics: Applied Physics, Chemistry, Graphene, Nanotechnology


Graphene, buckyballs, and carbon nanotubes now have a new family member, the nanocone, adding to the types of all-carbon nanostructures with remarkable electronic and optical characteristics and bringing its own promising properties. (J. Am. Chem. Soc., 2019, DOI: 10.1021/jacs.9b06617) Such molecules could be useful for developing efficient organic solar cells or as sensor molecules.

Organic chemist Frank Würthner and postdoctoral researcher Kazutaka Shoyama of the University of Würzburg came up with the method for synthesizing the nanocones, which are 1.68 nm in diameter and 0.432 nm tall. A five-atom ring of carbons forms the cone’s tip. The team used a cross-coupling annulation cascade to add hexagons around the edges of the ring until the molecule grew to 80 carbons. The team added five nitrogen atoms around the periphery of the cone, increasing the crystal’s solubility.

 

Nanocones extend the graphene toolbox, Neil Savage, Chemical & Engineering News

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Cyclocarbon...

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From left to right, precursor molecule C24O6, intermediates C22O4 and C20O2 and the final product cyclo [18]carbon C18 created on surface by dissociating CO masking groups using atom manipulation. The bottom row shows atomic force microscopy (AFM) data using a CO functionalized tip. Credit: IBM Research

 

Topics: Applied Physics, Atomic Force Microscopy, Chemistry, Nanotechnology, Research


A team of researchers from Oxford University and IBM Research has for the first time successfully synthesized the ring-shaped multi-carbon compound cyclocarbon. In their paper published in the journal Science, the group describes the process they used and what they learned about the bonds that hold a cyclocarbon together.

Carbon is one of the most abundant elements, and has been found to exist in many forms, including diamonds and graphene. The researchers with this new effort note that much research has been conducted into the more familiar forms (allotropes) how they are bonded. They further note that less well-known types of carbon have not received nearly as much attention. One of these, called cyclocarbon, has even been the topic of debate. Are the two-neighbor forms bonded by the same length bonds, or are there alternating bonds of shorter and longer lengths? The answer to this question has been difficult to find due to the high reactivity of such forms. The researchers with this new effort set themselves the task of finding the answer once and for all.

The team's approach involved creating a precursor molecule and then whittling it down to the desired form. To that end, they used atomic force microscopy to create linear lines of carbon atoms atop a copper substrate that was covered with salt to prevent the carbon atoms from bonding with the subsurface. They then joined the lines of atoms to form the carbon oxide precursor C24O6, a triangle-shaped form. Next, the team applied high voltage through the AFM to shear off one of the corners of the triangle, resulting in a C22O4 form. They then did the same with the other two corners. The result was a C18 ring—an 18-atom cyclocarbon. After creating the ring, the researchers found that the bonds holding it together were the alternating long- and short-type bonds that had been previously suggested.

 

Ring-shaped multi-carbon compound cyclocarbon synthesized, Bob Yirka , Phys.org

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