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The technique we offer here is found to be useful to familiarize technicians who work in the areas of applied optics, such as chemistry, electronics, water contamination, and optical instruments with Mie scattering techniques, and who may not have a formal introduction to the electromagnetic theory. One specific area in which these techniques might be useful is the study of aerosols that may arise when naturally produced droplets from humans, such as those produced by coughing, sneezing, talking, and breathing, are present, as it happens in response to the Severe Acute Respiratory Syndrome Coronavirus 2, also known as SARS-CoV-2.High-voltage silicon dynistors, which are turned on by means of initiating a shock ionization process in silicon, have unique capabilities with regard to switching of current pulses of a nanosecond duration. This paper describes the design of shock-ionized dynistors (SIDs) optimized to reduce the energy loss during switching. The use of these SIDs allows for a twofold reduction in the triggering generator’s power consumption. The results of this study show that it is possible to effectively increase the power switched in the nanosecond range through the use of SIDs with a higher operating voltage as well as to effectively reduce the energy loss in the SIDs by increasing the areas of their semiconductor structures. Moreover, it is possible to create switches that are able to switch nanosecond pulses with a power of more than 10 MW based on SIDs connected in series.Electrical impedance myography (EIM) is as an experimental technique that associates muscle impedance with muscular activity. Changes in muscle impedance during contraction occur mainly due to changes in the morphological and physiological characteristics of muscles that lead to different impeditivities in comparison with the resting condition. There is no consensus on the details of muscular impedance during muscle activity. EIM measurements on humans are also influenced by factors such as the electrode-skin interface, layers of skin and fat, and the connective tissue that can generate undesirable effects in the impedance signal. These effects can be avoided if EIM measurements are carried out directly on the muscle by using the models of animals. This study investigates changes in the EIM signal in the gastrocnemius muscles of Wistar rats during different levels of muscular contraction. In vivo experiments were conducted on 19 male rats. The muscle was exposed, fixed on a load cell, and electrically stimulated to evoke different levels of muscle contraction. Signals of the components of impedance were analyzed against the muscular force signal. The results show moderate correlations (p less then 0.05) among the impedance-related parameters of resistance (r = -0.76), reactance (r = 0.57), and phase (r = 0.53). In addition to providing an experimental protocol for the invasive collection of data on electrical impedance to minimize problems associated with surface electrodes, this study shows that of the components of impedance, resistance is most affected by the intensity of muscular contractions and that morphological changes influence impedance mainly at low intensities.We report on the functional capabilities of our field emission (FE) measurement systems. The samples are prepared and inserted under clean room conditions and can be precisely xyz-positioned, heat-treated, and investigated in different vacuum environments and temperatures. The FE scanning microscope is a unique microscope being used for the localization of FE sites with high lateral resolution by means of extraction voltage U(x, y) or emission current I(x, y) maps over the cathode area of 25 × 25 mm2 and measuring the FE properties of localized emission sites or individual emitters. In contrast, the integral measurement system with the luminescent screen provides real-time integral information about the distribution of emission sites over the whole cathode during long- and short-term current stability measurements, thus allowing us to investigate the properties of various materials and their applications. Commissioning results with the upgraded systems using a silicon emitter array and a point-type graphene emitter will be given to demonstrate that both FE measurement techniques are very useful for an improved understanding and tailoring of materials for applications. The results showed that point-type graphene emitters are more preferable for practical applications. Using simulation software, a suitable triode configuration for point emitters was designed, and a current transmission ratio of ∼100% was obtained. The FE current stability of graphene emitters at pressures >10-3 Pa can be improved by heating the cathode at 100 °C-300 °C for 1 min-30 min. Finally, point-type graphene film emitters were used for transmission-type x-ray sources, and their applications in imaging and fluorescence spectroscopy are presented.Surface nuclear magnetic resonance (SNMR) technology is widely used in the detection of groundwater. However, the dead time arising from the coupling effect of the transmitting circuit on the receiving coil results in partial or complete loss of the SNMR signal. This situation is especially unfavorable for the detection of short relaxation time targets. To solve this problem, we analyzed the shortcomings of the traditional SNMR launch system, and we propose a new transmission method based on an untuned constant voltage-clamped technology to overcome the problems of high resonance voltage, an uncontrollable shutdown process, and long shutdown times. Untuned transmission topology without a matching capacitor, pulse width modulation, and a constant voltage-clamped technique were applied to guide the current rise and shutdown of the system in a controllable way using an integer-period transmission pulse. selleck kinase inhibitor A simulation experiment comparing the traditional method of transmission and this new method was conducted. The results showed that not only can the new method control the transmission current shutdown process but it can also avoid the delay in response. When the transmitting current drops from 10 A to 0.12 µA, the traditional method requires 2.29 ms and the new method requires only 4 µs. The new transmission system that we have developed based on an untuned constant voltage-clamped technology can improve the level of the transmitting current effectively and shorten the shutdown time.