Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: chemistry – Page 108

Life on Earth began from a single-celled microbe, while the rise to the multicellular world in which we live arose due a vital chemical process known as biomineralization, during which living organisms produce hardened mineralized tissue, such as skeletons. Not only did this phenomenon give rise to the plethora of body plans we see today, but it also had a major impact on the planet’s carbon cycle.

Fossil skeletons of cloudinids (Cloudina), tubular structures comprised of carbonate cones up to ~1.5cm in length, have been found in Tsau Khaeb National Park, Namibia, dating back to 551–550 million years ago in the Ediacaran (~635–538 million years ago). Dr. Fred Bowyer, from the University of Edinburgh, and colleagues aimed to use these fossils to define the location, timing and reason for why biomineralization initiated on Earth and the magnitude of its impact.

New research published in Earth and Planetary Science Letters combines sediment analysis with geochemical data in the form of carbon and (the same element with different atomic masses) from limestones in the Kliphoek Member, Nama Group. The research team suggest this rock was once deposited in a during a lowstand before a period of transition to open marine conditions.

Read more | >

Separating molecules is critical to producing many essential products. For example, in petroleum refining, the hydrocarbons—chemical compounds composed of hydrogens and carbons—in crude oil are separated into gasoline, diesel and lubricants by sorting them based on their molecular size, shape and weight. In the pharmaceutical industry, the active ingredients in medications are purified by separating drug molecules from the enzymes, solutions and other components used to make them.

These separation processes take a substantial amount of energy, accounting for roughly half of U.S. industrial energy use. Traditionally, molecular separations have relied on methods that require intensive heating and cooling that make them very energy inefficient.

We are chemical and biological engineers. In our newly published research in Science, we designed a new type of membrane with nanopores that can quickly and precisely separate a diverse range of molecules under harsh industrial conditions.

Read more | >

In a surprising new study, researchers at the University of Minnesota Twin Cities have found that the electron beam radiation that they previously thought degraded crystals can actually repair cracks in these nanostructures.

The groundbreaking discovery provides a new pathway to create more perfect crystal nanostructures, a process that is critical to improving the efficiency and cost-effectiveness of materials that are used in virtually all electronic devices we use every day.

“For a long time, researchers studying nanostructures were thinking that when we put the crystals under radiation to study them that they would degrade,” said Andre Mkhoyan, a University of Minnesota chemical engineering and materials science professor and lead researcher in the study. “What we showed in this study is that when we took a crystal of titanium dioxide and irradiate it with an electron , the naturally occurring narrow actually filled in and healed themselves.”

Read more | >

“The surprising thing we found is that in a particular kind of crystal lattice, where electrons become stuck, the strongly coupled behavior of electrons in d atomic orbitals actually act like the f orbital systems of some heavy fermions,” said Qimiao Si, co-author of a study about the research in Science Advances

<em> Science Advances </em> is a peer-reviewed, open-access scientific journal that is published by the American Association for the Advancement of Science (AAAS). It was launched in 2015 and covers a wide range of topics in the natural sciences, including biology, chemistry, earth and environmental sciences, materials science, and physics.

Read more | >

A kilonova is a bright blast of electromagnetic radiation that happens when two neutron stars or a neutron star and a stellar-mass black hole collide and merge.

When these collisions occur, a vast amount of material is ejected from the neutron stars, the ultradense cores of massive stars that have reached the ends of their lives. This matter is rich in neutral particles called neutrons, and in this violent sea of particles around a neutron star merger, the heaviest elements of the periodic table are forged. These include gold and platinum, radioactive materials such as uranium, and the iodine that flows through our blood. In fact, many pieces of jewelry owe their existence to a kilonova-triggering event.

Read more | >

The powdery material that NASA officials unveiled on Wednesday looked like asphalt or charcoal, but was easily worth more than its weight in diamonds. The fragments were from a world all their own—pieces of the asteroid Bennu, collected and returned to Earth for analysis by the OSIRIS-REx mission. The samples hold chemical clues to the formation of our solar system and the origin of life-supporting water on our planet.

The clay and minerals from the 4.5 billion-year-old rock had been preserved in space’s deep freeze since the dawn of the solar system. Last month, after a seven-year-long space mission, they parachuted to a desert in Utah, where they were whisked away by helicopter.

And now those pristine materials sit in an airtight vessel in a clean room at NASA’s Johnson Space Center, where researchers like University of Arizona planetary scientist Dante Lauretta are getting their first chance to study the sample up close.

Read more | >

Some asteroids are dense. So dense in fact, that they may contain heavy elements outside of the periodic table, according to a new study on mass density.

The team of physicists from The University of Arizona say they were motivated by the possibility of Compact Ultradense Objects (CUDOs) with a mass density greater than Osmium, the densest naturally occurring, stable element, with its 76 protons.

“In particular, some observed asteroids surpass this mass density threshold. Especially noteworthy is the asteroid 33 Polyhymnia,” the team writes in their study, adding that “since the mass density of asteroid 33 Polyhymnia is far greater than the maximum mass density of familiar atomic matter, it can be classified as a CUDO with an unknown composition.”

Read more | >

When it comes to human longevity, you might envision nanobots helping our bodies operate more efficiently. But our bodies are biological machines in their own right, evolved to handle any situation in the real world from illness to cold to hunger. Our bodies heal themselves, and they can be programmed to do so if we understood that language better.

This video talks about DNA and genes, and the epigenetic mechanisms that read that information. The epigenetic clock is one way to measure the age of cells, and this can be reversed with current technologies. We discuss experiments by David Sinclair, which made blind mice see again, and experiments by Greg Fahy, which regenerated the immune system of humans and reset their cellular age by 2 years.

Asking our bodies to heal themselves could be one of the largest medical breakthroughs ever, instead of trying mainly chemical means of medication. And it has significant implications for whether or not we can achieve longevity escape velocity and continue to live more or less indefinitely. This promises to be a very interesting topic.

#aging #longevity #science.

Continue reading “Unlocking immortality: the science of reversing aging” | >

The first people to make and use quantum dots were glassmakers. Working thousands of years ago, they realized that the same chemical mixture could turn glass into different colors, depending on how they heated it.

This year’s Nobel Prize in Chemistry honors three scientists who, along with their colleagues, students, and staff, figured out why the ancient glassmakers’ methods worked — and how to control them much more precisely. During the waning days of the Cold War, Alexei Ekimov and Louis Brus, working in separate labs on opposite sides of the Iron Curtain, both discovered the same thing: that tiny crystals (just millionths of a millimeter wide) act very differently than larger pieces of the exact same material. These tiny, weird crystals are called quantum dots, and just a few years after the Berlin Wall fell, Moungi Bawendi figured out how to mass-produce them.

That changed everything. Quantum dots are crystals so small that they follow different rules of physics than the materials we’re used to. Today, these tiny materials help surgeons map different types of cells in the body, paint vivid color images on QLED screens, and give LED lights a warmer glow.

Read more | >

Absorption spectroscopy is an analytical chemistry tool that can determine if a particular substance is present in a sample by measuring the intensity of the light absorbed as a function of wavelength. Measuring the absorbance of an atom or molecule can provide important information about electronic structure, quantum state, sample concentration, phase changes or composition changes, among other variables, including interaction with other molecules and possible technological applications.

Molecules with a high probability of simultaneously absorbing two photons of low-energy light have a wide array of applications: in molecular probes for , as a substrate for data storage in dense three-dimensional structures, or as vectors in medicinal treatments, for example.

Studying the phenomenon by means of direct experimentation is difficult, however, and computer simulation usually complements spectroscopic characterization. Simulation also provides a microscopic view that is hard to obtain in experiments. The problem is that simulations involving relatively require several days of processing by supercomputers or months by conventional computers.

Read more | >