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Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 11:29am

A wing's teardrop form forces air to flow quickly over its top, creating a low-pressure area that pulls the plane up. At the same time, air pushes against the bottom of the wing, adding upward pressure. Designers call the combination of this pull and push "lift." Changes in flight conditions or a drop in an aircraft's speed can result in stall, rapidly reducing lift.

The study uncovered the physics by which the flaps improved lift and identified two ways that the flaps control air moving around the wing. One of these control mechanisms had not been previously identified.

The researchers uncovered the new mechanism, called shear layer interaction, when they were testing the effect of a single flap near the front of the wing. They found that the other mechanism is only effective when the flap is at the back of the wing.

The researchers tested configurations with a single flap and with multiple flaps ranging from two rows to five rows. They found that the five-row configuration improved lift by 45%, reduced drag by 30% and enhanced the overall wing stability.

The discovery of this new mechanism unlocked a secret behind why birds have these feathers near the front of the wings and how we can use these flaps for aircraft. Especially because we found that the more flaps you add to the front of the wing, the higher the performance benefit.

This is the power of bioinspired design!

Wissa, Aimy, Distributed feather-inspired flow control mitigates stall and expands flight envelope, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2409268121. doi.org/10.1073/pnas.2409268121

Part 2

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 11:27am

Bird wings inspire new approach to flight safety

Taking inspiration from bird feathers,  engineers have found that adding rows of flaps to a remote-controlled aircraft's wings improves flight performance and helps prevent stalling, a condition that can jeopardize a plane's ability to stay aloft.

These flaps can both help the plane avoid stall and make it easier to regain control when stall does occur.

The flaps mimic a group of feathers, called covert feathers, that deploy when birds perform certain aerial maneuvers, such as landing or flying in a gust. Biologists have observed when and how these feathers deploy, but no studies have quantified the aerodynamic role of covert feathers during bird flight.

Engineering studies have investigated covert-inspired flaps for improving engineered wing performance, but have mostly neglected that birds have multiple rows of covert feathers. The present study has advanced the technology by demonstrating how sets of flaps work together and exploring the complex physics that governs the interaction.

This new  the technique is an easy and cost-effective way to drastically improve flight performance without additional power requirements.

The covert flaps deploy or flip up in response to changes in airflow, requiring no external control mechanisms. They offer an inexpensive and lightweight method to increase flight performance without complex machinery. They're essentially just flexible flaps that, when designed and placed properly, can greatly improve a plane's performance and stability.

Part 1

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 11:13am

Is it true that trees pollute the air?

(and Why Your Coworker's Scientific Citations Don't Mean They're Right)

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 10:45am

Almost a third of asthma cases are attributable to long-term exposure to fine particular matter, global study suggests

Drawing on evidence involving about 25 million people worldwide, an international research team led by the Max Planck Institute for Chemistry demonstrates that long-term exposure to ambient PM_2.5 significantly increases the risk of asthma, affecting both children and adults. The researchers find that approximately 30% of new asthma cases worldwide were linked to fine particulate matter (PM_2.5) exposure, highlighting the dramatic threat air pollution poses to public health.

Asthma is currently an incurable disease that severely impairs quality of life, with recurring symptoms such as wheezing, coughing, and shortness of breath. As of today, about 4% of the world's population suffers from asthma, with more than 30 million new cases arising annually.

Evidence suggests that long-term exposure to air pollution of fine particulate matter (PM_2.5) is an important risk factor for developing asthma.

Researchers have conducted a comprehensive global meta-analysis  and found this is correct. 

The research team determined the data from 68 epidemiological studies from 2019 conducted across 22 countries, including those in North America, Western Europe, East Asia, South Asia, and Africa. They conclude that there is now sufficient evidence with high confidence level to support an association between long-term exposure to ambient PM_2.5 and asthma.

Ruijing Ni et al, Long-term exposure to PM2.5 has significant adverse effects on childhood and adult asthma: A global meta-analysis and health impact assessment, One Earth (2024). DOI: 10.1016/j.oneear.2024.09.022

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 10:23am

During the rehearsal, the scientists used trapped protons as a stand-in for antiprotons. Protons are a key ingredient of every atom, the simplest of which is hydrogen (one proton and one electron.) But storing protons as loose particles and then moving them onto a truck is a challenge because any tiny disturbance will draw the unbonded protons back into an atomic nucleus.

When it's transported by road, our trap system is exposed to acceleration and vibrations, and laboratory experiments are usually not designed for this. Scientists needed to build a trap system that is robust enough to withstand these forces, and they have now put this to a real test for the first time.
the biggest potential hurdle isn't currently the bumpiness of the road but traffic jams.

If the transport takes too long, they will run out of helium at some point.
Liquid helium keeps the trap's superconducting magnet at a temperature below 8.2 Kelvin: its maximum operating temperature. If the drive takes too long, the magnetic field will be lost and the trapped particles will be released and vanish as soon as they touch ordinary matter.
Eventually, they want to be able to transport antimatter to our dedicated precision laboratories at the Heinrich Heine University in Düsseldorf, which will allow us to study antimatter with at least 100-fold improved precision
In the longer term, they want to transport it to any laboratory in Europe. This means that they need to have a power generator on the truck. They are currently investigating this possibility.
After this successful test, which included ample monitoring and data-taking, the team plans to refine its procedure with the goal of transporting antimatter next year.

"This is a totally new technology that will open the door for new possibilities of study, not only with antiprotons but also with other exotic particles, such as ultra-highly-charged ions.
Another experiment, PUMA, is preparing a transportable trap. Next year, it plans to transport antiprotons 600 meters from the ADH hall to CERN's ISOLDE facility in order to use them to study the properties and structure of exotic atomic nuclei.
Source: CERN
Part 3

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 10:19am

Antimatter is a naturally occurring class of particles that is almost identical to ordinary matter except that the charges and magnetic properties are reversed.
According to the laws of physics, the Big Bang should have produced equal amounts of matter and antimatter. These equal-but-opposite particles would have quickly annihilated each other, leaving a simmering but empty universe. Physicists suspect that there are hidden differences that can explain why matter survived and antimatter all but disappeared.
The BASE experiment aims to answer this question by precisely measuring the properties of antiprotons, such as their intrinsic magnetic moment, and then comparing these measurements with those taken with protons. However, the precision the experiment can achieve is limited by its location.

The accelerator equipment in the AD hall generates magnetic field fluctuations that limit how far we can push our precision measurements.
If scientists want to get an even deeper understanding of the fundamental properties of antiprotons, they need to move out.
This is where BASE-STEP comes in. The goal is to trap antiprotons and then transfer them to a facility where scientists can study them with a greater precision. To be able to do this, they need a device that is small enough to be loaded onto a truck and can resist the bumps and vibrations that are inevitable during ground transport.
The current apparatus—which includes a superconducting magnet, cryogenic cooling, power reserves, and a vacuum chamber that traps the particles using magnetic and electric fields—weighs 1,000 kilograms and needs two cranes to be lifted out of the experimental hall and onto the truck. Even though it weighs a ton, BASE-STEP is much more compact than any existing system used to study antimatter. For example, it has a footprint that is five times smaller than the original BASE experiment, as it must be narrow enough to fit through ordinary laboratory doors.
Part 2

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 10:16am

Scientists transport protons in truck, paving way for antimatter delivery

Antimatter might sound like something out of science fiction, but at the CERN Antiproton Decelerator (AD), scientists produce and trap antiprotons every day. The BASE experiment can even contain them for more than a year—an impressive feat considering that antimatter and matter annihilate upon contact.

The CERN AD hall is the only place in the world where scientists are able to store and study antiprotons. But this is something that scientists working on the BASE experiment hope to change one day with their subproject BASE-STEP: an apparatus designed to store and transport antimatter.

Most recently, the team of scientists and engineers took an important step towards this goal by transporting a cloud of 70 protons in a truck across CERN's main site.

If you can do it with protons, it will also work with antiprotons. The only difference is that you need a much better vacuum chamber for the antiprotons.

This is the first time that loose particles have been transported in a reusable trap that scientists can then open in a new location and then transfer the contents into another experiment. The end goal is to create an antiproton-delivery service from CERN to experiments located at other laboratories.

Part 1

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 9:32am

Using the 88-Inch Cyclotron accelerator at Lawrence Berkeley National Laboratory, the team produced a beam that averaged 6 trillion titanium ions per second that exited the cyclotron. These impacted the plutonium target, which had a circular area of 12.2 cm, over a 22-day period. Making a slew of measurements, they determined that 290-livermorium had been produced via two different nuclear decay chains.

"This is the first reported production of a SHE [superheavy element] near the predicted island of stability with a beam other than 48-calcium," they concluded. The reaction cross section, or probability of interaction, did decrease, as was expected with heavier beam isotopes, but "success of this measurement validates that discoveries of new SHE are indeed within experimental reach."
The discovery represents the first time a collision of non-magic nuclei has shown the potential to create other superheavy atoms and isotopes (both), hopefully paving the way for future discoveries. About 110 isotopes of superheavy elements are known to exist, but another 50 are expected to be out there, waiting to be uncovered by new techniques such as this.

J. M. Gates et al, Toward the Discovery of New Elements: Production of Livermorium ( Z=116 ) with Ti50, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.133.172502

Part 4

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 9:31am

Theoretical models of the nucleus have successfully predicted the production rates of superheavy elements below oganesson using actinide targets and beams of isotopes heavier than 48-calcium. These models also agree that to produce elements with Z=119 and Z=120, beams of 50-titanium would work best, having the highest cross sections.

But not all necessary parameters have been pinned down by theorists, such as the necessary energy of the beams, and some of the masses needed for the models haven't been measured by experimentalists. The exact numbers are important because the production rates of the superheavy elements could otherwise vary enormously.

Several experimental efforts to produce atoms with proton numbers from 119 to 122 have already been attempted. All have been unsatisfactory, and the limits they determined for the cross sections have not allowed different theoretical nuclear models to be constrained. Gates and his team investigated the production of isotopes of livermorium (Z=116) by beaming 50-titanium onto targets of 244-Pu (plutonium).
Part 3

Comment by Dr. Krishna Kumari Challa on October 29, 2024 at 9:30am

The island of stability is a region where superheavy elements and their isotopes—nuclei with the same number of protons but different numbers of neutrons—may have much longer half-lives than the elements near it. It's been expected to occur for isotopes near Z=112.

While there have been several techniques to discover superheavy elements and create their isotopes, one of the most fruitful has been to bombard targets from the actinide series of elements with a beam of calcium atoms, specifically an isotope of calcium, 48-calcium (48Ca), that has 20 protons and 28 (48 minus 20) neutrons. The actinide elements have proton numbers from 89 to 103, and 48Ca is special because it has a "magic number" of both protons and neutrons, meaning their numbers completely fill the available energy shells in the nucleus.
Proton and/or neutron numbers being magic means the nucleus is extremely stable; for example, 48Ca has a half-life of about 60 billion billion (6 x 1019) years, far larger than the age of the universe. (By contrast, 49Ca, with just one more neutron, decays by half in about nine minutes.)

These reactions are called "hot-fusion" reactions. Another technique saw beams of isotopes from 50-titanium to 70-zinc accelerated onto targets of lead or bismuth, called "cold-fusion" reactions. Superheavy elements up to oganesson (Z=118) were discovered with these reactions.

But the time needed to produce new superheavy elements, quantified via the cross section of the reaction which measures the probability they occur, was taking longer and longer, sometimes weeks of running time. Being so close to the predicted island of stability, scientists need techniques to go further than oganesson. Targets of einsteinium or fermium, themselves superheavy, cannot be sufficiently produced to make a suitable target.
Part 2

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