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Experimental comparison of spherically bent HAPG and Ge crystals
摘要： The Orion high-resolution X-ray (OHREX) imaging spherically bent crystal spectrometer, operated with both image plates and CCD cameras, provides time-averaged plasma diagnostics through high-resolution spectroscopy with good signal-to-noise at the Orion laser facility. In order to provide time-resolved spectra, the OHREX will be out?tted with a streak camera, and in this case, even higher signal to noise will be desired. Using the OHREX’s sister instrument, the EBIT High-resolution X-ray (EBHiX) spectrometer, at the LLNL electron beam ion trap EBIT-I, we therefore compare the ef?ciency of a high-quality Ge (111) crystal (2d = 6.532 ?) with that of a higher integrated re?ectivity, but lower-resolution highly annealed pyrolytic graphite (HAPG) crystal (2d = 6.708 ?) in the energy range 2408–2452 eV. We ?nd that the HAPG provides overall more signal across the entire image; however, because of the much better focusing properties of the Ge crystal, the latter provides more signal within the central 100 μm of the spatial pro?le in the cross-dispersion direction and is thus more suitable for the narrow entrance window of the Livermore-built streak camera.
关键词： HAPG,Ge crystals,X-ray spectroscopy,spherically bent crystals,plasma diagnostics
更新于2025-09-09 09:28:46
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[IEEE 2018 28th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) - Greifswald, Germany (2018.9.23-2018.9.28)] 2018 28th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) - Vacuum-Arc Anode Phenomena: New Findings and New Applications
摘要： The vacuum arc modes from the viewpoint of anode activity have traditionally been considered as a diffuse arc, footpoints, anode spots, and an intense arc. Recent studies carried out jointly by the IHCE SB RAS and the INP-Greifswald have made it possible to identify anodic plume and anode spot type 2 as new modes of a high-current vacuum arc, specific for electrodes made of a copper-chromium composition. The anode plume appears either immediately before the anode spot of type 2, or immediately after the extinction of the anode spot of type 2. The appearance of the plume before the spot is unstable, while after the spot the plume is stable. Appearance of the plume is an indicator of the intense vapor flux of the anode material, which can reduce the breaking capacity of the vacuum circuit breaker (VCB). Implementation of the VCB operating mode free of both the anode spot type 2 and anode plume allows a more successful recovering of the electric strength of the VCB after current zero.
关键词： vacuum arc,plasma diagnostics,plasma sources,circuit breakers
更新于2025-09-09 09:28:46
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Direct comparison of pulsed spark discharges in air and water by synchronized electrical and optical diagnostics
摘要： In this study, a direct comparison was made between pulsed spark discharges in air and water in sub-mm gaps. The discharges were ignited at atmospheric pressure in the same discharge arrangement for air and water, using a solid-state microsecond pulse source with ≈1 μs voltage rise time (Umax up to 37 kV). Fast voltage and current measurements were synchronized with iCCD imaging with high spatial resolution on symmetrical half-sphere tungsten electrodes (electrode gaps of up to 0.7 mm for air and 0.3 mm for water). The breakdown voltage and electrical ?eld strength, maximal current, transferred charge, consumed electrical energy and discharge emission structure (e.g. discharge channel diameters) was obtained for all cases. Using the synchronization of the electrical data and the iCCD imaging, current and energy densities were estimated for the sparks in air and water. It was found that the breakdown voltage, the discharge current, the transferred charge, and the consumed electrical energy increase with the gap distance, and that this dependency is much stronger for discharges in water (compared to air). Due to the use of the same discharge arrangement and the same applied voltage, the di?erence in the discharge characteristics was directly quanti?ed.
关键词： energy density,spark discharges,water,optical diagnostics,breakdown voltage,electrical diagnostics,air,discharge current
更新于2025-09-04 15:30:14
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[IEEE 2018 48th European Microwave Conference (EuMC) - Madrid, Spain (2018.9.23-2018.9.27)] 2018 48th European Microwave Conference (EuMC) - Non-invasive Detection and Monitoring of Sustained Glycemic Fluctuations using Mm-Wave Spectroscopy
摘要： The biomedical industry has prominently grown during the last decades that has led to the introduction of new non-invasive techniques in the medical field. Particularly, microwave and mm-wave spectroscopy are good candidates for such goals. Recently, we have demonstrated that mm-wave spectroscopy in the W-band has great potential for the non-invasive detection of hyperglycemia typically associated to diabetes using animal models. In such approach a clear discrimination, based on blind classification, between hyperglycemic and control cases was achieved. In this work, the same spectroscopic technique is used to dynamically detect and monitor drug-induced diabetes on a group of mice. Our results provide strong evidence that sustained glycemic fluctuations can be closely followed by the proposed method with a temporal resolution of a few days.
关键词： Mm-wave,Diabetes,Hyperglycemia,Non-invasive diagnostics,spectroscopy,Functional Principal Component Analysis
更新于2025-09-04 15:30:14
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[IEEE 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz2018) - Nagoya, Japan (2018.9.9-2018.9.14)] 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Development of NbN polarization sensitive KID for Fusion Applications
摘要： In this paper, we present a preliminary study for the design of Kinetic Inductance Detectors (KID) sensitive to polarization, which will be employed in an innovative polarimetric system for fusion plasma diagnostics applications.
关键词： polarization sensitivity,Kinetic Inductance Detectors,NbN,fusion plasma diagnostics,polarimetry
更新于2025-09-04 15:30:14
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The Measuring System for the Thomson Scattering Diagnostics of the GOL-3 and GDT Facilities
摘要： The measuring system for Thomson scattering diagnostics of the GOL-3 and GDT facilities at the Budker Institute of Nuclear Physics is described. The system has a modular architecture and is based on eight-channel measuring subsystems, including photodetectors, two-channel recorders (ADC12500), synchronization modules, and the Ethernet/UART communication channel adapter. The photodetectors are based on avalanche photodiodes and are operable in the frequency range of 0–50 MHz. The ADC12500 recorders are used to measure scattering signals with a duration of ~20–30 ns at a sampling rate of to 500 MHz and an amplitude resolution of 12 bits and accumulate data in a buffer memory with a capacity as large as 2 MB.
关键词： ADC12500,avalanche photodiodes,GDT,measuring system,Thomson scattering diagnostics,GOL-3
更新于2025-09-04 15:30:14
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Handbook of Bioelectronics (Directly Interfacing Electronics and Biological Systems) || CMOS nanowire biosensing systems
摘要： Lowering the costs of healthcare and increasing its accessibility is a critical need of today’s society. Miniaturized electronic sensors are a possible way to both improve healthcare and lower the cost of medical diagnostics. Their small size and portability can lead to integration into personalized diagnostics tools and emergency care. In addition, faster, smaller and more efficient sensors can greatly impact chemical and biological safety.
关键词： biosensing,CMOS,nanowire,diagnostics,healthcare
更新于2025-09-04 15:30:14
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High resolution spectropolarimetry: from Astrophysics to ECR plasmas
摘要： Electron Cyclotron Resonance (ECR) plasmas with high density and high temperature are required by the injectors for the Accelerators and by interdisciplinary studies in Astrophysics and Nuclear Astrophysics. Understanding and further developing magnetic traps requires accurate measurements of the physical properties of the con?ned plasma, such as density, temperature and ionization state, not allowed by the commonly used diagnostic methods (imaging, low resolution spectroscopy). Here, we show the potentiality of a few diagnostic applications of high resolution spectroscopy in the visible range, routinely used in Astrophysics to measure stellar physical parameters such as e?ective temperature, surface gravity, chemical abundances. In addition, we show that polarimetry is a powerful technique to derive the morphology of stellar magnetic ?elds, whose knowledge is necessary for a correct interpretation of spectra from magnetized plasmas. An application of these non-invasive methods to B-min ECR plasma concerning optical emission is discussed in view of a better understanding of the plasma structure, magnetic con?nement properties and heating processes.
关键词： Plasma diagnostics - charged-particle spectroscopy,Polarisation,Ion sources (positive ions, negative ions, electron cyclotron resonance (ECR), electron beam (EBIS))
更新于2025-09-04 15:30:14
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Research on Beam Emission Spectroscopy Combined HL-2A Tokamak Real Experimental Data With Spectra Simulation Code
摘要： A beam emission spectroscopy (BES) diagnostic system has been developed on HL-2A tokomak. Combined with motional Stark effect (MSE) diagnostics, the BES could assess the radial electric ?eld Er and the safety factor q, which play an important role in plasma control and impurity transport processes. A simulation of spectra (SOS) code has been developed for spectra simulations based on various tokamak devices’ real situations. It can be used for designing visible spectral diagnostics systems and predicting their performance. In this paper, based on the HL-2A real experimental running parameters, we used the SOS code to simulate BES and MSE spectra. These spectra were consistent with experimental data ?tting results. The SOS code was also able to get the safety factor q and other parameters. The results reveal that the SOS code could be used to design similar diagnostic systems for ITER in the future.
关键词： neutral beam injection (NBI) diagnostics,motional Stark effect (MSE),simulation of spectra (SOS),Beam emission spectroscopy (BES)
更新于2025-09-04 15:30:14
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Fully convolutional networks in multimodal nonlinear microscopy images for automated detection of head and neck carcinoma: A pilot study
摘要： Background: A fully convolutional neural networks (FCN)-based automated image analysis algorithm to discriminate between head and neck cancer and non-cancerous epithelium based on nonlinear microscopic images was developed. Methods: Head and neck cancer sections were used for standard histopathology and co-registered with multimodal images from the same sections using the combination of coherent anti-Stokes Raman scattering, two-photon excited fluorescence, and second harmonic generation microscopy. The images analyzed with semantic segmentation using a FCN for four classes: cancer, normal epithelium, background, and other tissue types. Results: A total of 114 images of 12 patients were analyzed. Using a patch score aggregation, the average recognition rate and an overall recognition rate or the four classes were 88.9% and 86.7%, respectively. A total of 113 seconds were needed to process a whole-slice image in the dataset. Conclusion: Multimodal nonlinear microscopy in combination with automated image analysis using FCN seems to be a promising technique for objective differentiation between head and neck cancer and noncancerous epithelium.
关键词： digital pathology,semantic segmentation,diagnostics,second-harmonic generation,convolutional neural networks,two-photon excited fluorescence,spectral histopathology,image analysis,head and neck cancer,coherent anti-stokes Raman scattering
更新于2025-09-04 15:30:14