Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: materials

Cambridge/Jena (16.11.2020) Linkages between organic and inorganic materials are a common phenomenon in nature, e.g., in the construction of bones and skeletal structures. They often enable combinations of properties that could not be achieved with just one type of material. In technological material development, however, these so-called hybrid materials still represent a major challenge today.

A new class of hybrid glass materials

Researchers from the Universities of Jena (Germany) and Cambridge (GB) have now succeeded in creating a new class of hybrid glass materials that combine organic and inorganic components. To do this, the scientists use special material combinations in which chemical bonds between organometallic and inorganic glasses can be generated. They included materials composed of organometallic networks—so-called metal-organic frameworks (MOFs)—which have recently been experiencing rapidly increasing research interest. This is primarily because their framework structures can be created in a targeted manner, from the length scale of individual molecules up to a few nanometers. This achieves a control of porosity which can be adapted to a large number of applications, both in terms of the size of the pores and their permeability, and in terms of the chemical properties prevailing on the pore surfaces.

Read more | >

A 2002 article published in the American Psychological Association’s prevention & treatment, by University of Connecticut psychology professor Irving Kirsch titled, “The Emperor’s New Drugs,” made some more shocking discoveries. He found that 80 percent of the effect of antidepressants, as measured in clinical trials, could be attributed to the placebo effect. This professor even had to file a Freedom of Information Act (FOIA) request to get information on the clinical trials of the top antidepressants.

A Baylor School of Medicine study, published in 2002 in the New England Journal of Medicine, looked at surgery for patients with severe and debilitating knee pain. Many surgeons know there is no placebo effect in surgery, or so most of them believe. The patients were divided into three groups. The surgeons shaved the damaged cartilage in the knee of one group. For the second group, they flushed out the knee joint, removing all of the material believed to be causing inflammation. Both of these processes are the standard surgeries people go through who have severe arthritic knees. The third group received a “fake” surgery, the patients were only sedated and tricked that they actually had the knee surgery. For the patients not really receiving the surgery, the doctors made the incisions and splashed salt water on the knee as they would in normal surgery. They then sewed up the incisions like the real thing and the process was complete.

Read more | >

A group of researchers led by Sir Andre Geim and Dr. Alexey Berdyugin at The University of Manchester have discovered and characterized a new family of quasiparticles named ‘Brown-Zak fermions’ in graphene-based superlattices.

The team achieved this breakthrough by aligning the atomic lattice of a layer to that of an insulating boron nitride sheet, dramatically changing the properties of the graphene sheet.

The study follows years of successive advances in graphene-boron nitride superlattices which allowed the observation of a fractal pattern known as the Hofstadter’s butterfly—and today (Friday, November 13) the researchers report another highly surprising behavior of particles in such structures under applied magnetic field.

Read more | >

In recent years, researchers have been trying to develop new types of highly performing electronic devices. As silicon-based devices are approaching their maximum performance, they have recently started exploring the potential of fabricating electronics using alternative superconductors.

Two-dimensional (2-D) semiconductors, such as graphene or tungsten diselenide (WSe2), are particularly promising for the development of electronics. Unfortunately, however, controlling the electronic properties of these materials can be very challenging, due to the limited amount of space within their lattices to incorporate impurity dopants (a process that is critical for controlling the carrier type and electronic properties of materials).

Researchers at University of California, Los Angeles, have recently devised an approach that could enable the development of programmable devices made of 2-D semiconductors. This approach, presented in a paper published in Nature Electronics, leverages a superionic phase transition in silver iodide to tailor the carrier type within devices made of WSe2 via a process called switchable ionic doping.

Read more | >

Researchers discover an unexpected new class of superconducting material.

Superconducting materials are traditionally classed into two types: s-wave and d-wave. A third type, p-wave, has long been predicted. Now, however, researchers in the US, Germany and Japan say they may have discovered a fourth, unexpected type of superconductor: g-wave. The result, obtained thanks to high-precision resonant ultrasound spectroscopy measurements on strontium ruthenate, could shed fresh light on the Cooper pairing mechanisms in so-called unconventional superconductors.

Read more | >

Engineers at Cornell University have developed a new technique for 3D printing metallic objects – and it involves blasting titanium particles at supersonic speeds. The resulting metals are very porous, which makes them particularly useful for biomedical objects like implants and replacement joints.

Traditional 3D printing involves a nozzle depositing plastic, hydrogels, living cells or other materials layer by layer to build up an object. Metal parts and objects are usually 3D printed in other ways, such as firing a laser at a bed of metal powder to selectively melt sections into the desired shape, or firing metal powder at high speeds at a substrate to fuse the particles together.

The latter method is known as “cold spray,” and the new technique expands on that base. The Cornell team blasted titanium alloy particles, each measuring between 45 and 106 microns wide, at speeds up to 600 m (1,969 ft) per second (for reference, the speed of sound in air is around 340 m (1,115 ft) per second). The team calculated this as the ideal speed – any faster, and the particles would disintegrate too much on impact to bond to each other.

Read more | >

Groundbreaking science is often the result of true collaboration, with researchers in a variety of fields, viewpoints and experiences coming together in a unique way. One such effort by Clemson University researchers has led to a discovery that could change the way the science of thermoelectrics moves forward.

Graduate research assistant Prakash Parajuli; research assistant professor Sriparna Bhattacharya; and Clemson Nanomaterials Institute (CNI) Founding Director Apparao Rao (all members of CNI in the College of Science’s Department of Physics and Astronomy) worked with an international team of scientists to examine a highly efficient thermoelectric material in a new way—by using light.

Their research has been published in the journal Advanced Science and is titled “High zT and its origin in Sb-doped GeTe single crystals.”

Read more | >

“Anything you take from Earth to the moon is an added weight that you don’t want to carry, so if you can make these materials in situ it saves you a lot of time, effort and money,” said Ian Mellor, the managing director of Metalysis, which is based in Sheffield.

Analyses of rocks brought back from the moon reveal that oxygen makes up about 45% of the material by weight. The remainder is largely iron, aluminium and silicon. In work published this year, scientists at Metalysis and the University of Glasgow found they could extract 96% of the oxygen from simulated lunar soil, leaving useful metal alloy powders behind.

NASA and other space agencies are in advanced preparations to return to the moon, this time to establish a permanent lunar base, or “moon village” where nations will operate alongside private companies on critical technologies such as life support, habitat construction, energy generation and food and materials production.

Read more | >