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Could be used for fires aswell.


The vortex ring gun is an experimental non-lethal weapon for crowd control that uses high-energy vortex rings of gas to knock down people or spray them with marking ink or other chemicals.

The concept was explored by the US Army starting in 1998, and by some commercial firms. Knockdown of distant individuals currently seems unlikely even if the rings are launched at theoretical maximum speed.[1] As for the delivery of chemicals, leakage during flight is still a problem.[ citation needed ]

Weapons based on similar principles but different designs and purposes have been described before, typically using acetylene-air or hydrogen–oxygen explosions to create and propel the vortices.[2].

Editor’s note: This article is part of a supporting engagement with the Electromagnetic Defense Task Force’s efforts in order to inform readers on the vulnerabilities within the electromagnetic spectrum. For the printer friendly version click here.

Abstract

In spring 2019, a group of nearly 200 military, government, academic, and private industry experts in various areas of electromagnetic defense gathered for the second Electromagnetic Defense Task Force (EDTF) summit. During this time a full analytical and technical review was initiated on the recently released report titled “High-Altitude Electromagnetic Pulse and the Bulk Power System: Potential Impacts and Mitigation Strategies” authored by the Electric Power Research Institute (EPRI). This essay outlines the strengths and weaknesses of the report and aims to generate further discussion among industry, policy makers, military, and academia to ensure the nation is adequately prepared for any potential electromagnetic event.

Theoretical physicists from SISSA and the University of California at Davis have developed a new approach to heat transport in materials, which finally allows crystals, polycrystalline solids, alloys and glasses to be treated on the same solid footing. It opens the way to the numerical simulation of the thermal properties of a vast class of materials in important fields such as energy saving, conversion, scavenging, storage, heat dissipation, shielding and the planetary sciences, which have thus far dodged a proper computational treatment. The research has been published in Nature Communications.

Heat dissipates over time. In a sense, is the defining feature of the arrow of time. In spite of the foundational importance of heat transport, the father of its modern theory, Sir Rudolph Peierls, wrote in 1961, “It seems there is no problem in modern physics for which there are on record as many false starts, and as many theories which overlook some essential feature, as in the problem of the thermal conductivity of nonconducting crystals.”

A half-century has passed since, and heat transport is still one of the most elusive chapters of theoretical materials science. As a matter of fact, no unified approach has been able to treat crystals and (partially) disordered solids on equal footing, thus hindering the efforts of generations of materials scientists to simulate certain materials, or different states of the same material occurring in the same physical system or device with the same accuracy.

With a flourish of a silk curtain at the Farnborough Air Show on July 16, British defense secretary Gavin Williamson unveiled a full-scale model of the Tempest, the UK’s concept for a domestically built twin-engine stealth fighter to enter service in the 2030s. The Tempest will supposedly boast a laundry list of sixth-generation technologies such as being optionally-manned, mounting hypersonic or directed energy weapons, and capability to deploy and control drone swarms. However, it may also represent a Brexit-era gambit to revive defense cooperation with Germany and France.

London has seeded “Team Tempest” with £2 billion ($2.6 billion) for initial development through 2020. Major defense contractor BAE System is leading development with the Royal Air Force, with Rolls Royce contributing engines, European firm MBDA integrating weapons, and Italian company Leonardo developing sensors and avionics.

Design will supposedly be finalized in the early 2020s, with a flyable prototype planned in 2025 and production aircraft entering service in 2035, gradually replacing the RAF’s fourth-generation Typhoon fighters and complementing F-35 stealth jets. This seventeen-year development cycle is considered ambitious for something as complicated and expensive as a stealth fighter.

A University of Texas at Dallas physicist has teamed with Texas Instruments Inc. to design a better way for electronics to convert waste heat into reusable energy.

The collaborative project demonstrated that silicon’s ability to harvest energy from heat can be greatly increased while remaining mass-producible.

Dr. Mark Lee, professor and head of the Department of Physics in the School of Natural Sciences and Mathematics, is the corresponding author of a study published July 15 in Nature Electronics that describes the results. The findings could greatly influence how circuits are cooled in electronics, as well as provide a method of powering the sensors used in the growing “internet of things.”

TeraWatt Technology announced that its 4.5Ah prototype solid-state battery design achieved a record-breaking energy density of 432Wh/kg (1122Wh/L) in validation tests conducted by third parties, including TOYO System based in Japan.

Branded as TERA3.0, this 4.5Ah next-generation design will be available for select early adopters in 2021 and full release in 2022. TeraWatt Technology continues to further iterate the TERA3.0 line of design, as well as further develop additional designs including different cell formats, sizes and energy capacities.

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Theoretical physicists at Trinity College Dublin are among an international collaboration that has built the world’s smallest engine—which, as a single calcium ion, is approximately ten billion times smaller than a car engine.

Work performed by Professor John Goold’s QuSys group in Trinity’s School of Physics describes the science behind this tiny motor. The research, published today in international journal Physical Review Letters, explains how random fluctuations affect the operation of microscopic machines. In the future, such devices could be incorporated into other technologies in order to recycle and thus improve .

The engine itself—a single calcium ion—is electrically charged, which makes it easy to trap using electric fields. The working substance of the engine is the ion’s “intrinsic spin” (its angular momentum). This spin is used to convert heat absorbed from laser beams into oscillations, or vibrations, of the trapped ion.

A group of researchers led by Skoltech Professor Pavel Troshin studied coordination polymers, a class of compounds with scarcely explored applications in metal-ion batteries, and demonstrated their possible future use in energy storage devices with a high charging/discharging rate and stability. The results of their study were published in the journal Chemistry of Materials.

The charging/discharging rate is one of the key characteristics of lithium-ion batteries. Most modern commercial batteries need at least an hour to get fully charged, which certainly limits the scope of their application, in particular, for electric vehicles. The trouble with active materials, such as the most popular anode material, graphite, is that their capacity decays significantly, as their charging rate increases. To retain the battery capacity at high charging rates, the active electrode materials must have high electronic and ionic conductivity, which is the case with the newly-discovered coordination polymers that are derived from and salts of , such as nickel or copper. Although these compounds hold a great promise, their application in lithium-ion batteries remains virtually unexplored.

A recent study undertaken by a group of scientists from Skoltech and the Institute for Problems of Chemical Physics of RAS led by Professor P. Troshin in collaboration with the University of Cologne (Germany) and the Ural Federal University, focused on tetraaminobenzene-based linear polymers of nickel and copper. Although the linear polymers exhibited much lower initial electronic conductivity as compared to their two-dimensional counterparts, it transpired that they can be used as anode materials that get charged/discharged in less than a minute, because their conductivity increases dramatically after the first discharge due to lithium doping.