INFORMATION:
A professor from RUDN University developed new liquid crystals
2021-01-22
(Press-News.org) A professor from RUDN University together with his Indian colleagues synthesized and studied new dibenzophenazine-based liquid crystals that could potentially be used in optoelectronics and solar panels. The results of the study were published in the Journal of Molecular Liquids.
Liquid crystals are an intermediate phase between a liquid and a solid body. They are ordered like regular chrystals but at the same time have a flow like liquids. It is this duality that allows them to be used in organic LEDs and LCDs. Unlike other liquid crystals, discotic ones (DLC) are capable of self-assembly into ordered structures. This makes them a promising material for industrial electronics, namely, for the production of displays. A professor from RUDN University together with his Indian colleagues synthesized and described new dibenzophenazine-based DLCs.
"Discotic liquid crystals are interesting because of their ability to form self-assembled ordered columnar structures. In such structures, an electric charge can move along the column, which makes them useful for optoelectronic devices such as organic LEDs, organic field-effect transistors (OFET), photoelectric solar elements, and sensors," said Prof. Viktor Belyaev, a Ph.D. in Technical Sciences from the Department of Mechanics and Mechatronics at RUDN University.
DLCs consist of disc-shaped molecules aligned in columns. In the center of each disc, there is an aromatic ring (a cyclical organic fragment) surrounded by chains of other organic fragments. Due to this aromatic center, a DLC can transfer a charge along the axis of a column. Prof. Belyaev developed discotic liquid crystals with an aromatic compound called dibenzophenazine in the center. As for the chains that surrounded it, the team tried three different types of fragments. The molecular structure of the new DLCs was studied using spectral, X-ray diffraction, and elementary analysis. Then, the team tested the three groups of DLCs in a set of experiments.
The experiments showed that alkoxy thiol chains increased the polarity of the molecules in liquid crystals thus improving the internal structure of the columns and making them more even. All new DLCs were able to withstand temperatures up to 330?. However, the crystals that consisted of smaller molecules (i.e. the ones with their aromatic center surrounded by alkyl thiols) lost their intermediary status and transitioned from the liquid crystal to the liquid form at lower temperatures (55.1 ?) that the crystals from the other two groups. This is due to the size of the molecules in the columns: the bigger they are, the more stable is the liquid crystal state.
"The new discotic liquid crystals could play an important role in organic optoelectronic devices and solar panels," added Prof. Viktor Belyaev from RUDN University.
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
Wet and wild: There's lots of water in the world's most explosive volcano
2021-01-22
There isn't much in Kamchatka, a remote peninsula in northeastern Russia just across the Bering Sea from Alaska, besides an impressive population of brown bears and the most explosive volcano in the world.
Kamchatka's Shiveluch volcano has had more than 40 violent eruptions over the last 10,000 years. The last gigantic blast occurred in 1964, creating a new crater and covering an area of nearly 100 square kilometers with pyroclastic flows. But Shiveluch is actually currently erupting, as it has been for over 20 years. So why would anyone risk venturing too close?
Researchers from Washington University in St. Louis, including Michael Krawczynski, assistant professor of earth ...
Exercising muscle combats chronic inflammation on its own
2021-01-22
DURHAM, N.C. - Biomedical engineers at Duke University have demonstrated that human muscle has an innate ability to ward off the damaging effects of chronic inflammation when exercised. The discovery was made possible through the use of lab-grown, engineered human muscle, demonstrating the potential power of the first-of-its-kind platform in such research endeavors.
The results appear online on January 22 in the journal Science Advances.
"Lots of processes are taking place throughout the human body during exercise, and it is difficult to tease apart which systems and cells are doing what inside an active person," said Nenad Bursac, professor of biomedical engineering at Duke. "Our engineered muscle ...
From fins to limbs
2021-01-22
When tetrapods (four-limbed vertebrates) began to move from water to land roughly 390 million years ago it set in motion the rise of lizards, birds, mammals, and all land animals that exist today, including humans and some aquatic vertebrates such as whales and dolphins.
The earliest tetrapods originated from their fish ancestors in the Devonian period and are more than twice as old as the oldest dinosaur fossils. They resembled a cross between a giant salamander and a crocodile and were about 1-2 meters long, had gills, webbed feet and tail fins, and ...
UK public supports usage of tracking technology and immunity passports in global pandemic
2021-01-22
New research suggests the majority of people in the UK are willing to use privacy-encroaching tracking technology and support the introduction of 'immunity passports' to protect themselves and others in the COVID-19 pandemic.
The study, published today in the journal PLOS ONE, found more than two thirds of respondents overall would accept some form of smartphone tracking app to help manage social distancing and the relaxation of a full public lockdown.
However, its findings are not reflected in the number of people who have downloaded the NHS Test and Trace app, prompting calls for this issue to be addressed.
Lead author Professor Stephan Lewandowsky, Chair in Cognitive Psychology at the University of Bristol, said: "Attitudes were surprisingly permissive and this ...
Climate and carbon cycle trends of the past 50 million years reconciled
2021-01-22
Predictions of future climate change require a clear and nuanced understanding of Earth's past climate. In a study published today in Science Advances, University of Hawai'i (UH) at Mānoa oceanographers fully reconciled climate and carbon cycle trends of the past 50 million years--solving a controversy debated in the scientific literature for decades.
Throughout Earth's history, global climate and the global carbon cycle have undergone significant changes, some of which challenge the current understanding of carbon cycle dynamics.
Less carbon dioxide in the atmosphere cools Earth and decreases weathering of rocks and minerals on land over long time scales. Less weathering should lead to a shallower calcite compensation depth (CCD), which is the depth in the ocean where ...
Crystal structures in super slow motion
2021-01-22
Laser beams can be used to change the properties of materials in an extremely precise way. This principle is already widely used in technologies such as rewritable DVDs. However, the underlying processes generally take place at such unimaginably fast speeds and at such a small scale that they have so far eluded direct observation. Researchers at the University of Göttingen and the Max Planck Institute (MPI) for Biophysical Chemistry in Göttingen have now managed to film, for the first time, the laser transformation of a crystal structure with nanometre resolution and in slow motion in an electron microscope. The results have been published in the journal Science.
The ...
University of Cincinnati research unveils possible new combo therapy for head and neck cancer
2021-01-22
Head and neck cancer is the sixth most common cancer worldwide, and while effective treatments exist, sadly, the cancer often returns.
Researchers at the University of Cincinnati have tested a new combination therapy in animal models to see if they could find a way to make an already effective treatment even better.
Since they're using a Food and Drug Administration-approved drug to do it, this could help humans sooner than later.
These findings are published in the journal END ...
NSAIDs might exacerbate or suppress COVID-19 depending on timing, mouse study suggests
2021-01-22
Washington, DC - January 22, 2021 - New research shows that non-steroidal anti-inflammatory drugs (NSAIDs) reduced both antibody and inflammatory responses to SARS-CoV-2 infection in mice. The study appears this week in the Journal of Virology, a publication of the American Society for Microbiology.
The research is important because "NSAIDs are arguably the most commonly used anti-inflammatory medications," said principal investigator Craig B. Wilen, Assistant Professor of Laboratory Medicine and Immunology, Yale University School of Medicine.
In addition to taking NSAIDs for chronic conditions such as arthritis, people take them "for shorter periods of time during infections, and [during] ...
Tiny particles that seed clouds can form from trace gases over open sea
2021-01-22
UPTON, NY - New results from an atmospheric study over the Eastern North Atlantic reveal that tiny aerosol particles that seed the formation of clouds can form out of next to nothingness over the open ocean. This "new particle formation" occurs when sunlight reacts with molecules of trace gases in the marine boundary layer, the atmosphere within about the first kilometer above Earth's surface. The findings, published in the journal Nature Communications, will improve how aerosols and clouds are represented in models that describe Earth's climate so scientists can understand how the particles--and the processes that control them--might ...
Experts call for more pragmatic approach to higher education teaching
2021-01-22
Millions of students around the world could benefit if their educators adopted a more flexible and practical approach, say Swansea University experts.
After analysing the techniques current being used in higher education, the researchers are calling for a pragmatic and evidence-based approach instead.
Professor Phil Newton, director of learning and teaching at of Swansea University Medical School, said: "Higher education is how we train those who carry out important professional roles in our society. There are now more than 200 million students in HE worldwide and this number is likely to double again over the next decade.
"Given the size, impact, importance and cost of ...