Science Daily August 18, 2020 The Trace Vapor Generator for Explosives and Narcotics (TV-Gen) sampling device designed by a team of researchers in the US (Naval Research Laboratory, research institution, National Research Council) can be used with a broad range of analytes, detection systems, materials, and sensors. It can switch easily between the clean and analyte vapor streams. The TV-Gen system utilizes nebulization of aqueous analyte solutions and a control box that provides dedicated computer control with logging capabilities. Resultant vapor streams are stable over several hours, with the vapor concentration controlled by a combination of aqueous analyte solution concentration, […]
Category Archives: Sensors
Novel magnetic stirrer speaks to lab equipment
Science Daily August 3, 2020 Researchers in the UK have developed a device, called “Smart Stirrer”. When immersed in a solution, it can in situ monitor physical properties of the chemical reaction such as the temperature, conductivity, visible spectrum, opaqueness, stirring rate, and viscosity. This data is transmitted real-time over a wireless connection to an external system, such as a PC or smartphone. The flexible open-source software architecture allows effortless programming of the operation parameters of the Smart Stirrer in accordance with the end-user needs. In a series of experiments its capability for many hours of continuous telemetry with fine […]
Metal-breathing bacteria could transform electronics, biosensors, and more
Science Daily July 28, 2020 Some bacteria that are adapted to specific geochemical or biochemical environments can create interesting and novel materials. Researchers at the Rensselaer Polytechnic Institute synthesised molybdenum disulfide nanomaterials at the site of S. oneidensis biofilms grown in the presence of molybdenum trioxide and sodium thiosulfate. Analysis revealed the presence of molybdenum disulfide nanoparticle aggregates 50–300 nm in diameter with both hexagonal and rhombohedral polytypes. The use of S. oneidensis offers the advantage of significantly reduced heat and chemical solvent input compared to conventional methods of synthesizing molybdenum disulfide nanoparticles. The process can be used for the generation […]
Liquid crystals create easy-to-read, color-changing sensors
Nanowerk July 11, 2020 Inspired by the ability of chameleons to change color by using temperature to direct the skin tissue that contains nanocrystals reflecting light, to expand or contract, an international team of researchers (USA – University of Chicago, University of South Carolina, University of North Texas, Cornell University, Argonne National Laboratory, Mexico, Turkey, Colombia) has developed a way to stretch and strain liquid crystals to generate different colors. They dispersed chiral droplets in polymer films and deformed it by inducing uniaxial or biaxial stretching. Their measurements are interpreted by resorting to simulations of the corresponding systems, thereby providing […]
‘Nanometrology lab on a chip’ within reach thanks to new compact, optical sensor
Nanowerk May 20, 2020 On-chip compact and integrated optical motion sensing micro- and nano-optomechanical platforms that typically exploit narrow spectral resonances require tunable lasers with narrow linewidth and low spectral noise, which makes the integration of the read-out extremely challenging. Researchers in the Netherlands report a step towards the practical application of nanomechanical sensors, by presenting a sensor with ultrawide (∼80 nm) optical bandwidth. It is based on a nanomechanical, three-dimensional directional coupler with integrated dual-channel waveguide photodiodes and displays small displacement imprecision as well as large dynamic range (>30 nm). The broad optical bandwidth releases the need for a tunable laser […]
Catching nuclear smugglers: Fast algorithm could enable cost-effective detectors at borders
EurekAlert April 30, 2020 An international team of researchers (USA – University of Michigan, University of Illinois, Los Alamos National Laboratory, UK) developed an algorithm capable of identifying weak radiation signals, such as might be seen from plutonium encased materials that absorb radiation. It works even in the presence of a high radiation background, including everyday sources such as cosmic rays from space and radon from the rock underfoot. Based on their results, they believe the use of their algorithm could improve the ability of radiation portal monitors at national borders to tell the difference between potential smuggling activity and […]
Broad spectrum: Novel hybrid material proves an efficient photodetector
Phys.org April 9, 2020 The MOF compound developed by researchers in Germany comprises an organic material integrated with iron ions. The MOF forms superimposed layers with semiconducting properties, which makes it potentially interesting for optoelectronic applications. They found that the light sensitivity was dependent on temperature and wavelength from 400 to 1,575 nanometers. The spectrum of radiation goes from ultraviolet to near infrared. As the bandgap in the material is very small, only very little light energy is required to induce the electricity. The performance of the detector can be improved by cooling the detector down to lower temperatures and […]
Graphene underpins a new platform to selectively ID deadly strains of bacteria
Technology.org March 24, 2020 Point-of-care diagnostics that can reduce and/or prevent unneeded antibiotic prescriptions require highly specific probes with sensitive and accurate transducers that can be miniaturized and multiplexed, and that are easy to operate and cheap. Researchers at Boston College present several advances in the use of graphene field effect transistors (G-FET) including the first use of peptide probes to electrically detect antibiotic resistant bacteria in a highly specific manner. They have reduced the needed concentration for detection by employing dielectrophoresis which allows monitoring changes in the Dirac point due to individual bacterial cells. Rapid binding of bacterial cells […]
Atomic fingerprint identifies emission sources of uranium
Science Daily March 9, 2020 Isotopic ratios of radioactive releases into the environment are useful signatures for contamination source assessment. A ratio of uranium trace isotopes may serve as a superior oceanographic tracer. An international team of researchers (Austria, Australia, Denmark, Japan, Germany) analysed ratio on the atomic 233U/236U ratio analyzed in representative environmental samples. The ratios detected in compartments of the environment affected by releases of nuclear power production or by weapons fallout differ by one order of magnitude. Significant amounts of 233U were only released in nuclear weapons fallout. This makes the 233U/236U ratio a promising new fingerprint […]
A new AI chip can perform image recognition tasks in nanoseconds
MIT Technology Review March 4, 2020 Visual information is captured by a frame-based camera, converted into a digital format and processed afterwards using a machine-learning algorithm such as an artificial neural network (ANN). The large amount of data passed through the entire signal chain, however, results in low frame rates and high-power consumption. Researchers in Austria built a sensor based on a reconfigurable two-dimensional semiconductor photodiode array, and the synaptic weights of the network are stored in a continuously tunable photoresponsivity matrix. The sensor can itself constitute an ANN that can simultaneously sense and process optical images without latency. They […]