Journal articles on the topic 'Transient laser diagnostics'
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Irimiciuc, Stefan Andrei, Sergii Chertopalov, Jan Lancok, and Valentin Craciun. "Langmuir Probe Technique for Plasma Characterization during Pulsed Laser Deposition Process." Coatings 11, no. 7 (June 25, 2021): 762. http://dx.doi.org/10.3390/coatings11070762.
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The history of pulsed laser deposition (PLD) and transient plasmas generated by laser ablation is intertwined with the development of various techniques for its fundamental understanding. Some diagnostic tools have been developed to better suit the rapid transient nature of the plasma (space and time dependence of all parameters, fast decay and complex chemistry inside the plasma), whereas others have been adapted from basic plasma physics studies. Langmuir probe method has been used as a real-time in situ diagnostic tool for laser ablation and later for PLD. It remains a useful tool for the PLD community arsenal, which can easily be adapted to the development of new lasers and ablation regimes and new deposition configuration, being one of the most versatile techniques for plasma diagnostics. It is the cornerstone on which charge particles are analyzed and has led to several important discoveries, such as multiple peak distribution, selective acceleration during expansion, plume splitting, plasma turbulences and fluctuations. However, because the Langmuir probe theory adaptation from classical plasma physics is not straightforward, it might lead to misinterpretation and often incorrect analysis of data. This review analyzes the limits and understanding of the technique as a foundation for attaining its full potential, which can impact the way PLD is used. This is especially useful for the pressing need of real-time, in-situ diagnostics and feedback loops for systematic semi-industrial implementation of the PLD technique.
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Owada, Shigeki, Kyo Nakajima, Tadashi Togashi, Tetsuo Kayatama, and Makina Yabashi. "Single-shot arrival timing diagnostics for a soft X-ray free-electron laser beamline at SACLA." Journal of Synchrotron Radiation 25, no. 1 (January 1, 2018): 68–71. http://dx.doi.org/10.1107/s1600577517015284.
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Arrival timing diagnostics performed at a soft X-ray free-electron laser (FEL) beamline of SACLA are described. Intense soft X-ray FEL pulses with one-dimensional focusing efficiently induce transient changes of optical reflectivity on the surface of GaAs. The arrival timing between soft X-ray FEL and optical laser pulses was successfully measured as a spatial position of the reflectivity change. The temporal resolution evaluated from the imaging system reaches ∼10 fs. This method requires only a small portion of the incident pulse energy, which enables the simultaneous operation of the arrival timing diagnostics and experiments by introducing a wavefront-splitting scheme.
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Owada, Shigeki, Kyo Nakajima, Tadashi Togashi, Tetsuo Katayama, Hirokatsu Yumoto, Haruhiko Ohashi, and Makina Yabashi. "Arrival timing diagnostics at a soft X-ray free-electron laser beamline of SACLA BL1." Journal of Synchrotron Radiation 26, no. 3 (April 1, 2019): 887–90. http://dx.doi.org/10.1107/s1600577519002315.
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An arrival timing monitor for the soft X-ray free-electron laser (XFEL) beamline of SACLA BL1 has been developed. A small portion of the soft XFEL pulse is branched using the wavefront-splitting method. The branched FEL pulse is one-dimensionally focused onto a GaAs wafer to induce a transient reflectivity change. The beam branching method enables the simultaneous operation of the arrival timing diagnostics and experiments. The temporal resolution evaluated from the imaging system is ∼22 fs in full width at half-maximum, which is sufficient considering the temporal durations of the soft XFEL and the optical laser pulses.
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Nagler, Bob, Brice Arnold, Gary Bouchard, Richard F. Boyce, Richard M. Boyce, Alice Callen, Marc Campell, et al. "The Matter in Extreme Conditions instrument at the Linac Coherent Light Source." Journal of Synchrotron Radiation 22, no. 3 (April 21, 2015): 520–25. http://dx.doi.org/10.1107/s1600577515004865.
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The LCLS beam provides revolutionary capabilities for studying the transient behavior of matter in extreme conditions. The particular strength of the Matter in Extreme Conditions instrument is that it combines the unique LCLS beam with high-power optical laser beams, and a suite of dedicated diagnostics tailored for this field of science. In this paper an overview of the beamline, the capabilities of the instrumentation, and selected highlights of experiments and commissioning results are presented.
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Capotondi, F., L. Foglia, M. Kiskinova, C. Masciovecchio, R. Mincigrucci, D. Naumenko, E. Pedersoli, A. Simoncig, and F. Bencivenga. "Characterization of ultrafast free-electron laser pulses using extreme-ultraviolet transient gratings." Journal of Synchrotron Radiation 25, no. 1 (January 1, 2018): 32–38. http://dx.doi.org/10.1107/s1600577517015612.
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The characterization of the time structure of ultrafast photon pulses in the extreme-ultraviolet (EUV) and soft X-ray spectral ranges is of high relevance for a number of scientific applications and photon diagnostics. Such measurements can be performed following different strategies and often require large setups and rather high pulse energies. Here, high-quality measurements carried out by exploiting the transient grating process,i.e.a third-order non-linear process sensitive to the time-overlap between two crossed EUV pulses, is reported. From such measurements it is possible to obtain information on both the second-order intensity autocorrelation function and on the coherence length of the pulses. It was found that the pulse energy density needed to carry out such measurements on solid state samples can be as low as a few mJ cm−2. Furthermore, the possibility to control the arrival time of the crossed pulses independently might permit the development of a number of coherent spectroscopies in the EUV and soft X-ray regime, such as, for example, photon echo and two-dimensional spectroscopy.
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Mihaila, I., C. Ursu, A. Gegiuc, and G. Popa. "Diagnostics of plasma plume produced by laser ablation using ICCD imaging and transient electrical probe technique." Journal of Physics: Conference Series 207 (January 1, 2010): 012005. http://dx.doi.org/10.1088/1742-6596/207/1/012005.
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Funk, David J., W. Dale Breshears, Gary W. Laabs, and Blaine W. Asay. "Laser Diode Reflectometry and Infrared Emission Measurements of Permeating Gases at High Driving Pressures and Temperatures." Applied Spectroscopy 50, no. 2 (February 1996): 257–62. http://dx.doi.org/10.1366/0003702963906555.
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We report the use of infrared diode lasers in a diffuse reflection geometry for detection of the cyclotetramethylentetranitramine (HMX) combustion product CO permeating through a silicon carbide bed. We find that infrared emission and transient absorption are coincident with these pressure waves and demonstrate the feasibility of these diagnostics for detecting molecular species in hostile environments. We conclude from the experimental evidence that macroscopic convective heating may play a limited role in the deflagration-to-detonation transition (DDT) of porous explosives.
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RAMPONE, SALVATORE, VINCENZO PIERRO, LUIGI TROIANO, and INNOCENZO M. PINTO. "NEURAL NETWORK AIDED GLITCH-BURST DISCRIMINATION AND GLITCH CLASSIFICATION." International Journal of Modern Physics C 24, no. 11 (October 14, 2013): 1350084. http://dx.doi.org/10.1142/s0129183113500848.
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We investigate the potential of neural-network based classifiers for discriminating gravitational wave bursts (GWBs) of a given canonical family (e.g. core-collapse supernova waveforms) from typical transient instrumental artifacts (glitches), in the data of a single detector. The further classification of glitches into typical sets is explored. In order to provide a proof of concept, we use the core-collapse supernova waveform catalog produced by H. Dimmelmeier and co-Workers, and the data base of glitches observed in laser interferometer gravitational wave observatory (LIGO) data maintained by P. Saulson and co-Workers to construct datasets of (windowed) transient waveforms (glitches and bursts) in additive (Gaussian and compound-Gaussian) noise with different signal-to-noise ratios (SNR). Principal component analysis (PCA) is next implemented for reducing data dimensionality, yielding results consistent with, and extending those in the literature. Then, a multilayer perceptron is trained by a backpropagation algorithm (MLP-BP) on a data subset, and used to classify the transients as glitch or burst. A Self-Organizing Map (SOM) architecture is finally used to classify the glitches. The glitch/burst discrimination and glitch classification abilities are gauged in terms of the related truth tables. Preliminary results suggest that the approach is effective and robust throughout the SNR range of practical interest. Perspective applications pertain both to distributed (network, multisensor) detection of GWBs, where some intelligence at the single node level can be introduced, and instrument diagnostics/optimization, where spurious transients can be identified, classified and hopefully traced back to their entry points.
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Lipatov, Dmitriy Valentinovich, Elena Grigor'evna Bessmertnaya, Anatoliy Gennad'evich Kuzmin, Nataliya Borisovna Smirnova, Anna Anatol'evna Tolkacheva, and Timofey Alexandrovich Chistyakov. "Long-term outcomes of ophthalmosurgery in diabetic patients." Diabetes mellitus 14, no. 1 (March 15, 2011): 69–73. http://dx.doi.org/10.14341/2072-0351-6252.
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Diabetes morbidity grows steadily despite recent progress in its diagnostics and treatment. Its most frequent complication is retinopathy although thereare increasingly more cases of diabetic cataract, secondary rubeous (neovascular) glaucoma, eyelid diseases, and transient impairment of vision.Aim To analyse late results of ophthalmosurgery in diabetic patients with vision problems.Materials and methods Over 24,000 patients were examined from January 2006 to November 2010 at the Department of Diabetic Retinopathyand Ophthalmosurgery, Endocrinological Research Centre. Results of more than 2660 seances of retinal laser coagulation and about 350 surgicalinterventions for diabetic cataract and secondary neovascular glaucoma were available for analysis.Conclusion Timely and correct application of retinal laser coagulation, modern facoemulsification of complicated cataract and drainage surgeryof uncompensated secondary rubeous glaucoma produces good functional results and permits to preserve or even improve visual acuity. The efficacyof surgical intervention is directly related to the quality of diabetes compensation and depends on the joint efforts of ophthalmologists, endocrinologists,and anesthesiologists.
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KUEHL, TH, D. URSESCU, V. BAGNOUD, D. JAVORKOVA, O. ROSMEJ, K. CASSOU, S. KAZAMIAS, et al. "Optimization of the non-normal incidence, transient pumped plasma X-ray laser for laser spectroscopy and plasma diagnostics at the facility for antiproton and ion research (FAIR)." Laser and Particle Beams 25, no. 1 (February 28, 2007): 93–97. http://dx.doi.org/10.1017/s0263034607070152.
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Intense and stable laser operation with Ni-like Zr and Ag was demonstrated at pump energies between 2 J and 5 J energy from the PHELIX pre-amplifier section. A novel single mirror focusing scheme for the TCE x-ray laser (XRL) has been successfully implemented by the LIXAM/MBI/GSI collaboration under different pump geometries. This shows potential for an extension to shorter XRL wavelength. Generation of high quality XRL beams for XRL spectroscopy of highly charged ions is an important issue within the scientific program of PHELIX. Long range perspective is the study of nuclear properties of radioactive isotopes within the FAIR project.
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König, Karsten. "Two-Photon near Infrared Excitation in Living Cells." Journal of Near Infrared Spectroscopy 5, no. 1 (January 1997): 27–34. http://dx.doi.org/10.1255/jnirs.97.
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Non-linear effects due to two-photon near infrared (NIR) excitation of endogenous and exogenous cellular chromophores allow novel techniques in tissue, cell and biomolecule diagnostics, as well as in intracellular micromanipulation (e.g. intracellular photochemistry). Two-photon NIR excitation may also result in cell damage effects. The high photon intensities (1024 photons cm−2 s−1) required for non-resonant two-photon excitation can be achieved by diffraction-limited focusing of continuous wave (cw) laser beams (cw microbeams) with powers in the mW range. For example, NIR traps (“laser tweezers”) used as force transducers and micromanipulation tools in cellular and molecular biology are sources of two-photon excitation. NIR traps can induce two-photon excited visible fluorescence and, in the case of <800 nm-traps, UVA-like cell damage. Multimode cw microbeams may enhance non-linear effects due to longitudinal mode-beating. To perform high scan rate two-photon fluorescence imaging, the application of ultrashort laser pulses of moderate peak power but low average power (pulsed microbeams) is required. In NIR femtosecond microscopes, non-destructive imaging of two-photon excited fluorophores in various human and culture cells was demonstrated for <2 mW average powers, <200 mW peak powers and 400 GW cm−2 intensities (700–800 nm, ∼150 fs, ∼100 MHz). However, higher average power levels may result in failed cell reproduction and cell death due to intracellular optical breakdown. In addition, destructive transient local heating and μN force generation may occur.
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Sergeev, Vyacheslav A., Maksim Y. Salnikov, and Azat M. Nizametdinov. "THE QUALITY CONTROL OF PLATED-THROUGH HOLES OF PRINTED CIRCUIT BOARDS BY PULSED LASER HEATING." Автоматизация процессов управления 3, no. 65 (2021): 96–102. http://dx.doi.org/10.35752/1991-2927-2021-3-65-96-102.
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The article gives a brief overview of standard methods of quality control and defect diagnostics of plated-through holes (PTH) of printed circuit boards (PCB) and considers their main disadvantages. It scrutinizes the methods of thermal control, which are reduced to PTH heating and monitoring the temperature. The main disadvantage of common methods is that they require a contact during heating the PTH and temperature measurement, which leads to significant errors and low reliability of control. The article describes a non-contact method involving heating only one side of the PTH by a laser beam and non-contact temperature measurement of the PTH ends by an IR camera. The authors propose a thermal equivalent scheme of PTH to analyze the transient thermal processes in PTH, which takes into account the heat removal from the plating of PTH into the PCB material. It is shown that the quality of plating can be estimated by the temperature difference between the upper (heated) and lower ends of the PTH, and the quality of adhesion between PTH plating and the PCB material can be estimated by the ratio of temperature increments. The article describes peculiarities of this method and gives the results of its testing on a real sample.
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Witze, Peter O. "(3-18) Qualitative Laser-Induced Incandescence Measurements of Soot Emissions During Transient Operation of a Port Fuel-Injected Engine((D-2)Diagnostics 2-LII)." Proceedings of the International symposium on diagnostics and modeling of combustion in internal combustion engines 01.204 (2001): 81. http://dx.doi.org/10.1299/jmsesdm.01.204.81.
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Singh, Gurbind, Divya Sridharan, Mahmood Khan, and Polani B. Seshagiri. "Mouse embryonic stem cell-derived cardiomyocytes cease to beat following exposure to monochromatic light: association with increased ROS and loss of calcium transients." American Journal of Physiology-Cell Physiology 317, no. 4 (October 1, 2019): C725—C736. http://dx.doi.org/10.1152/ajpcell.00188.2019.
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We earlier established the mouse embryonic stem (ES) cell “GS-2” line expressing enhanced green fluorescent protein (EGFP) and have been routinely using it to understand the molecular regulation of differentiation into cardiomyocytes. During such studies, we made a serendipitous discovery that functional cardiomyocytes derived from ES cells stopped beating when exposed to blue light. We observed a gradual cessation of contractility within a few minutes, regardless of wavelength (nm) ranges tested: blue (~420–495), green (~510–575), and red (~600–700), with green light manifesting the strongest impact. Following shifting of cultures back into the incubator (darkness), cardiac clusters regained beatings within a few hours. The observed light-induced contractility-inhibition effect was intrinsic to cardiomyocytes and not due to interference from other cell types. Also, this was not influenced by any physicochemical parameters or intracellular EGFP expression. Interestingly, the light-induced cardiomyocyte contractility inhibition was accompanied by increased intracellular reactive oxygen species (ROS), which could be abolished in the presence of N-acetylcysteine (ROS quencher). Besides, the increased intracardiomyocyte ROS levels were incidental to the inhibition of calcium transients and suppression of mitochondrial activity, both being essential for sarcomere function. To the best of our knowledge, ours is the first report to demonstrate the monochromatic light-mediated inhibition of contractions of cardiomyocytes with no apparent loss of cell viability and contractility. Our findings have implications in cardiac cell biology context in terms of 1) mechanistic insights into light impact on cardiomyocyte contraction, 2) potential use in laser beam-guided (cardiac) microsurgery, photo-optics-dependent medical diagnostics, 3) transient cessation of hearts during coronary artery bypass grafting, and 4) functional preservation of hearts for transplantation.
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Vidal, T., L. Gallais, J. Faucheux, H. Capdevila, and Y. Pontillon. "Using laser remote heating to simulate extreme thermal heat loads on nuclear fuels." EPJ Web of Conferences 225 (2020): 08002. http://dx.doi.org/10.1051/epjconf/202022508002.
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Up to now, predicting accurately the Fission Gas Release (FGR) from high burn up UO2 and/or MOX (Mixed Oxide) fuels at off-normal conditions, such as power transient, reactivity-initiated accident (RIA) and loss-of-coolant accident (LOCA), is still a significant and very challenging task. For this purpose, different R&D programs have been carried out in France, as well as in other countries. This has been done with a specific emphasis on mechanisms which promote the FGR under accidental conditions. These studies can be performed thanks to dedicated integral experiments conducted in-pile (i.e. in Materials Testing Reactor) with the corresponding cost and constraints, or at the laboratory scale with annealing tests which allow to be representative of specific parameters (thermal history for instance). During these annealing tests under well-known conditions (temperature, atmosphere), both the absolute level and the time dependence of the released gases should be monitored, together with the corresponding fuel micro-structural changes, since experimental knowledge of fission gas release alone is not efficient enough. This approach requires more and more accurate on-line measurements. This corresponds to the driving force of the present work. In this contribution, we will present our progress in developing an experimental platform that can submit nuclear fuel and cladding samples to annealing tests involving very high temperatures (up to 2500°C) and very fast temperature ramp (up to thousands of °C/s) with controlled thermal gradients and temporal dynamics. This new platform implements innovative instrumentation, such as optical diagnostics to measure fuel fragmentation kinetics and infrared pyrometry for temperature monitoring. This experiment is based on a high-power laser (1.5kW) coupled to an experimental chamber with controlled atmosphere (Ar, N2, or vacuum) and specific optical components. Based on the spatial beam profile and temporal power function of the laser, it is possible which such a system to produce complex spatio-temporal temperature gradients, relevant for addressing different research needs. It provides access to extreme conditions that are very difficult to reach with other means. Particularly, one of main objectives of this work is to investigate conditions of Reactivity Initiated Accident (RIA). The first experiments performed on inactive materials, non-irradiated uranium dioxide, is presented in order to highlight the capabilities of this technique.
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Ivancic, S. T., W. Theobald, K. Churnetski, M. Michalko, D. Willistein, W. A. Bittle, S. P. Regan, et al. "Design of the high-yield time-gated x-ray hot-spot imager for OMEGA." Review of Scientific Instruments 93, no. 11 (November 1, 2022): 113521. http://dx.doi.org/10.1063/5.0101673.
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Time-resolved x-ray self-emission imaging of hot spots in inertial confinement fusion experiments along several lines of sight provides critical information on the pressure and the transient morphology of the hot spot on the University of Rochester’s OMEGA Laser System. At least three quasi-orthogonal lines of sight are required to infer the tomographic information of the hot spots of deuterium–tritium cryogenic layered implosions. OMEGA currently has two time-gated x-ray hot-spot imagers: the time-resolved Kirkpatrick–Baez x-ray microscope and the single-line-of-sight, time-resolved x-ray imager (SLOS-TRXI). The time-gated x-ray hot-spot imager (XRHSI) is being developed for use on OMEGA as the third line of sight for the high-yield operation of up to 4 × 1014 neutrons. XRHSI follows the SLOS-TRXI concept; however, it will have improved spatial and temporal resolutions of 5 μm and 20 ps, respectively. The simultaneous operation of the three instruments will provide 3-D reconstructions of the assembled hot-spot fuel at various times through peak thermonuclear output. The technical approach consists of a pinhole array imager and demagnifying time-dilation drift tube that are coupled to two side-by-side hybrid complementary metal–oxide semiconductor (hCMOS) image sensors. To minimize the background and to harden the diagnostics, an angled drift-tube assembly shifting the hCMOS sensors out of the direct line of sight and neutron shielding will be applied. The technical design space for the instrument will be discussed and the conceptual design will be presented.
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Parigger, Christian G., James O. Hornkohl, and László Nemes. "Time-Resolved Spectroscopy Diagnostic of Laser-Induced Optical Breakdown." International Journal of Spectroscopy 2010 (October 22, 2010): 1–7. http://dx.doi.org/10.1155/2010/593820.
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Transient laser plasma is generated in laser-induced optical breakdown (LIOB). Here we report experiments conducted with 10.6-micron CO2 laser radiation, and with 1.064-micron fundamental, 0.532-micron frequency-doubled, 0.355-micron frequency-tripled Nd:YAG laser radiation. Characterization of laser induced plasma utilizes laser-induced breakdown spectroscopy (LIBS) techniques. Atomic hydrogen Balmer series emissions show electron number density of 1017 cm−3 measured approximately 10 μs and 1 μs after optical breakdown for CO2 and Nd:YAG laser radiation, respectively. Recorded molecular recombination emission spectra of CN and C2 Swan bands indicate an equilibrium temperature in excess of 7000 Kelvin, inferred for these diatomic molecules. Reported are also graphite ablation experiments where we use unfocused laser radiation that is favorable for observation of neutral C3 emission due to reduced C3 cation formation. Our analysis is based on computation of diatomic molecular spectra that includes accurate determination of rotational line strengths, or Hönl-London factors.
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Sorokoumov, Georgy. "Single event transients monitoring and diagnostic in FPGA." Facta universitatis - series: Electronics and Energetics 31, no. 3 (2018): 401–10. http://dx.doi.org/10.2298/fuee1803401s.
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Analysis of single event transients (SETs) generated in field programmable gate arrays (FPGA) under heavy charged particles (HCP) irradiation and SET suppression methods is performed. The circuit for FPGA SET detection is designed for transients generated both inside FPGA and outside at package pin level. SET registration inside FPGA is carried out as an event when logical cell is switched. The SET control schematic circuit efficiency has been comparatively verified using heavy ion accelerator and picosecond focused laser source. SET in FPGA experimental results are presented and discussed.
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Xu, X., and K. H. Song. "Radiative Transfer in Pulsed-Laser-lnduced Plasma." Journal of Heat Transfer 119, no. 3 (August 1, 1997): 502–8. http://dx.doi.org/10.1115/1.2824124.
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When a high-power pulsed laser interacts with materials, a plasma layer containing micrometer-size particles is formed above the target surface. The laser induced plasma changes the energy coupling mechanism between the laser beam and the target. This work investigates the radiative heat transfer process in the excimer laser generated plasma layer on the Ni specimen, in the laser fluence range between 1.5 and 5 J/cm2. Novel diagnostic techniques are developed to measure transient transmission and scattering of the thin plasma layer within the duration of the laser pulse. Based on the measurement results, radiative heat transfer analysis is performed to evaluate the radiative properties of the plasma layer, including the optical depth, the absorption coefficient, the single scattering phase function, and the scattering size parameters. Knowledge of the radiative properties of the laser induced plasma helps to understand the energy transfer process during laser-materials interaction. Further, this work demonstrates the feasibility of using the transient scattering measurement for in situ monitoring of the size of the laser ejected particles.
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Moosman, B., V. M. Bystritskii, C. J. Boswell, and F. J. Wessel. "Moiré deflectometry diagnostic for transient plasma, using a multipulse N2 laser." Review of Scientific Instruments 67, no. 1 (January 1996): 170–77. http://dx.doi.org/10.1063/1.1146566.
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THOMPSON, MARCELO SOTO, LOTTA GUSTAFSSON, SARA PÅLSSON, NIELS BENDSOE, MARIA STENBERG, CLAES AF KLINTEBERG, STEFAN ANDERSSON-ENGELS, and KATARINA SVANBERG. "Photodynamic therapy and diagnostic measurements of basal cell carcinomas using esterified and non-esterified δ-aminolevulinic acid." Journal of Porphyrins and Phthalocyanines 05, no. 02 (February 2001): 147–53. http://dx.doi.org/10.1002/jpp.325.
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Various optical techniques were used to investigate relevant parameters involved in photodynamic therapy (PDT) of human basal cell carcinomas (BCCs). The aim of the study was to compare the diagnostic and therapeutic outcome when using topically applied methyl-esterified δ-aminolevulinic acid (ALA-ME) and δ-aminolevulinic acid (ALA). A total of 35 pathologically verified BCCs in 14 patients were investigated. A diode laser, emitting continuous light at 633 nm, was used to induce PDT. The diagnostic measurements were performed before, during, and after PDT. Laser-induced fluorescence (LIF) was used to monitor the build-up of the ALA/ALA-ME-induced protoporphyrin IX ( PpIX ). The superficial tissue perfusion was measured with laser-Doppler perfusion imaging (LDPI) and the temperature of the lesion and the surrounding tissue was imaged with an IR-camera. A clear demarcation between the lesion and the normal skin was detected with LIF before the treatment for both PpIX precursors. The fluorescence measurements suggest that PpIX builds up to a higher degree and more selectively in the tumour following ALA-ME as compared to ALA. The LDPI measurements indicate a local transient restriction in blood perfusion immediately post-PDT. The measurement with the IR-camera revealed a temperature rise of about 1–2 °C during the treatment.
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Xiao, J. H., Y. C. Du, H. Q. Li, Y. T. Zhao, and L. Sheng. "Ultrafast high energy electron lens radiography suitable for transient electromagnetic field diagnosis." Journal of Instrumentation 17, no. 01 (January 1, 2022): P01033. http://dx.doi.org/10.1088/1748-0221/17/01/p01033.
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Abstract Transient electromagnetic fields — during or after laser/particle beam-target interaction — are a significant and hardly explored parameter. This paper proposes a new method for measuring transient electromagnetic fields, based on ultrafast high-energy electron lens radiography, that has a high tolerance for matter in the diagnosed region. With this method, a continuous point strength diagnosis helps to obtain delicate. Furthermore, dual-band diagnosis can be used to determine the field direction. To verify its feasibility, a 50 MeV electron lens radiography beamline was designed and optimized and a preliminary simulation for diagnosing circular magnetic fields ranging from 170 T·μm to 680 T·μm was performed. For a number density of 2000/pixel and ±10% non-uniformity, ±15% diagnostic field strength accuracy has been obtained. The direction diagnosis also works well. Combined with the advantages of high-energy electron beams, ultrafast high-energy electron lens radiography is suitable for transient electromagnetic field diagnosis.
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MUSCULUS, M., and L. PICKETT. "Diagnostic considerations for optical laser-extinction measurements of soot in high-pressure transient combustion environments." Combustion and Flame 141, no. 4 (June 2005): 371–91. http://dx.doi.org/10.1016/j.combustflame.2005.01.013.
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BORGHESI, M., D. H. CAMPBELL, A. SCHIAVI, O. WILLI, A. J. MACKINNON, D. HICKS, P. PATEL, L. A. GIZZI, M. GALIMBERTI, and R. J. CLARKE. "Laser-produced protons and their application as a particle probe." Laser and Particle Beams 20, no. 2 (April 2002): 269–75. http://dx.doi.org/10.1017/s0263034602202177.
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One of the most exciting results recently obtained in the ultraintense interaction research area is the observation of beams of protons with energies up to several tens of megaelectron volts, generated during the interaction of ultraintense picosecond pulses with solid targets. The particular properties of these beams (high brilliance, small source size, high degree of collimation, short duration) make them of exceptional interest in view of diagnostic applications. In a series of experiments carried out at the Rutherford Appleton Laboratory (RAL) and at the Lawrence Livermore National Laboratory (LLNL), the laser-produced proton beams have been characterized in view of their application as a particle probe for high-density matter, and applied to diagnose ultraintense laser–plasma interactions. In general, the intensity cross section of a proton beam traversing matter will be modified both by collisional stopping/scattering, and deflections caused by electric/magnetic fields. With a suitable choice of irradiation geometry and target parameters, the proton probe can be made mainly sensitive to the electric field distribution in the object probed. Therefore, point projection proton imaging appears as a powerful and unique technique for electric field detection in laser-irradiated targets and plasmas. The first measurements of transient electric fields in high-intensity laser-plasma interactions have been obtained with this technique.
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Patterson, J. R., J. A. Emig, K. B. Fournier, P. P. Jenkins, K. M. Trautz, S. W. Seiler, and J. F. Davis. "A Langmuir probe diagnostic for time-of-flight measurements of transient plasmas produced by high-energy laser ablation." Review of Scientific Instruments 83, no. 10 (October 2012): 10D725. http://dx.doi.org/10.1063/1.4739312.
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Kinash, I. O. "MICROBIOLOGICAL ASPECTS OF APPLYING CLINICAL DIAGNOSTIC COMPLEX OF ORTHODONTIC METHODS FOR RESTORING DESTROYED CORONAL PART OF TEETH." Актуальні проблеми сучасної медицини: Вісник Української медичної стоматологічної академії 21, no. 2 (June 17, 2021): 106–11. http://dx.doi.org/10.31718/2077-1096.21.2.106.
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Improving the quality of restoration of the destroyed coronal part of the teeth by orthopaedic methods has led to significant scientific and clinical interest and has been discussed in numerous reports, but the issues on reparative regeneration and restoration of the gingival margin relief in the area of the anterior group of teeth after reconstructive orthodontic measures in the case of restoration of destroyed tooth crowns and deep subgingival carious destruction have not been sufficiently studied yet. The purpose of this study was to investigate the microbiological peculiarities of applying a clinical diagnostic complex of manipulations designed to restore anterior teeth with cast posts to provide the grounds for long-term favourable outcomes of further orthopaedic treatment in order to obtain aesthetic appearance, taking into account the state of the surrounding soft tissues. To carry out high-quality preparation of periodontal tissues around the abutment tooth, patients underwent gingivectomy using a scalpel with a disposable blade, diode laser electrocoagulation and coagulation. The effectiveness of each method of the preparation of the marginal gingiva was evaluated by the findings of clinical and microbiological studies. We have found out all three tested methods of forming a new gum relief in the root area of a preserved tooth can significantly improve the qualitative and quantitative composition of the microflora in the stump area. A significant decrease in the frequency of biotope colonization by pathogenic and transient microorganisms and the improvement of the species composition in the local oral microbiocenosis can be achieved by cutting the hypertrophied epithelial edge of the cervical area with a microsurgical scalpel and using laser coagulation. Clinical and microbiological studies have confirmed the effectiveness of the clinical diagnostic complex of techniques for preparing the marginal gum around the root of the tooth, which is planned for orthodontic treatment with a post and an inlay. The use of a diode laser has been found to show the highest efficiency compared to other presented methods. All of the above techniques can be used in dental practice as methods of choice.
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Yabashi, Makina. "Status and future for time-resolved applications at Japanese XFEL facility SACLA." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C125. http://dx.doi.org/10.1107/s205327331409874x.
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Following the five-year construction and commissioning, SACLA has started operation for users in March 2012. As typical parameters, SACLA provides XFEL light in a photon energy range from 4 to 15 keV with a pulse energy of 0.5 mJ at 10 keV and a pulse duration less than 10 fs[1a,b]. Various fields of researches, including SFX/CDI, ultrafast chemistry, AMO, HEDS, and X-ray quantum optics are performed [2a]. ~50 proposals are performed per every year. For expanding the capacity, we are constructing new XFEL beamline, which will be open in 2015. For conducting high-resolution time-resolved experiments, it is crucially important for compensating possible timing jitter between XFEL and optical laser pulses. For this purpose, we have developed a timing diagnostic scheme, which utilizes x ray-pumped transient absorption of optical laser in semiconductor. We have evaluated a typical jitter as 130 fs in rms [2b]. Based on the scheme, we are constructing a dedicated system for post-process analysis, which will be operated in the autumn of 2014. We have developed a new scheme for time-resolved absorption spectroscopy, which combines a dispersive spectrometer with a grating-based beam splitter. Following the proof-of-principle test [3 a], we have successfully observed transient absorption signal in iron complex [3 b] in sub-ps resolution. For performing jitter-free X-pump/X-probe experiments, we have developed a two-color double-pulse scheme that uses variable-gap undulators and a small chicane [3 c]. A large and flexible wavelength separation of more than 30% with an ultraprecisely controlled time interval in the attosecond regime was achieved.
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Jenabi, Amin, Ali Hooshyar Zare, and Sobhan Erfantalab. "Voltammetry of Micro-Liter Electrolyte Samples on ITO Microelectrodes for Analyte Recognition." Key Engineering Materials 605 (April 2014): 601–4. http://dx.doi.org/10.4028/www.scientific.net/kem.605.601.
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Obtaining information on the nature of ionic species in electrolyte samples is in demand. The examination process must take less than ~1 min, and the test is expected to require small volume (micro-liter) samples. Here, we report electrolyte examination results with a simple voltammetry process carried out on thin film indium tin oxide micro-electrodes deposited on polyethylene terephthalate substrates and micromachined by CO2 laser ablation. The sample volume required is 2 μl, which is dropped manually on the electrodes with a sampler. The voltage waveform applied between the electrodes is a combination of positive and negative pulses of different magnitudes. The transient electric current passing through the electrolyte is monitored and plotted versus time. These plots are utilized as the finger prints of the related electrolyte samples. Pattern recognition methods are employed for information extraction from the obtained patterns. The diagnostic information extracted from these patterns proved sufficient for discrimination among KF, KCl and KI samples at various concentrations.
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Wyss, I., R. Rossi, and P. Gaudio. "A multi-wavelength approach to increase polarimeter diagnostic performance in nuclear fusion reactors." Journal of Instrumentation 17, no. 03 (March 1, 2022): C03044. http://dx.doi.org/10.1088/1748-0221/17/03/c03044.
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Abstract In future tokamaks, the huge variation of the plasma parameters during a discharge (ramp up, flat top, and ramp down) may involve that a diagnostic suitable for the flat top is not suitable for transients, and vice versa. Moreover, future reactors will start the experimental campaigns in safe scenarios, where events like disruptions are not critical, and they will increase their parameters gradually. Also in this case, a diagnostic optimised for the final target scenario may fail at the beginning of the experimental campaign. Laser-based polarimetry, a plasma diagnostic used in magnetized plasma to measure quantities that are related to the electron density, the magnetic field, and the electron temperature (in the case of relativistic effects), is a typical diagnostic that must be optimised for specific scenarios, since it is affected by several issues (refraction, type-I approximation, noise sensitivity) that limit its range of applicability. The aim of this work is to present a method to solve, or at least alleviate, this type of problem by using a multi-wavelength approach. The main idea consists of measuring the polarisation effects (Faraday rotation and Cotton-Mouton phase shift) with more than one wavelength and then calculating the plasma parameters by a weighted average of the measurements, where the weights are derived from the theory of polarimetry. The analysis is performed simulating the process of measurement introducing a casual error. The outcomes demonstrate that the adoption of a multi-wavelength polarimeter system brings a more accurate measurement in a wider range. Considering that next tokamaks will be implemented with a dual-wavelength interferometer, like the dispersion interferometer-polarimeter of ITER, this proposed approach could be taken into consideration to increase the performances of polarimetry.
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Gonzalez, José, Philippe Hapiot, Valery Konovalov, and Jean-Michel Savéant. "Investigating the reduction characteristics of transient free radicals by laser-pulse electron photo-injection—mechanism diagnostic criteria and determination of reactivity parameters from time-resolved experiments." Journal of Electroanalytical Chemistry 463, no. 2 (March 1999): 157–89. http://dx.doi.org/10.1016/s0022-0728(98)00435-5.
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Gericke, Beate, Jens Raila, Maria Deja, Sascha Rohn, Bernd Donaubauer, Britta Nagl, Sophie Haebel, Florian J. Schweigert, and Udo Kaisers. "Alteration of Transthyretin Microheterogeneity in Serum of Multiple Trauma Patients." Biomarker Insights 2 (January 2007): 117727190700200. http://dx.doi.org/10.1177/117727190700200014.
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Transthyretin (TTR) which exists in various isoforms, is a valid marker for acute phase response and subclinical malnutrition. The aim of the study was to investigate the relationship between inflammation, oxidative stress and the occurrence of changes in microheterogeneity of TTR. A prospective, observational study at a level-I trauma center of a large urban medical university was performed. Patients were severely injured (n = 18; injury severity score (ISS): 34–66), and were observed within the first 24 hours of admittance and over the following days until day 20 after injury. 20 healthy subjects, matched by age and sex, were used as controls. TTR was enriched by immunoprecipitation. Microheterogeneity of TTR was determined by linear matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Four major mass signals were observed for TTR representing native, S-cysteinylated, S-cysteinglycinylated and S-glutathionylated TTR. In the course of their ICU stay, 14 of the 18 patients showed a transient change in microheterogeneity in favour of the S-cysteinglycinylated form of TTR (p < 0.05 vs. controls). The occurrence of this variant was not associated with the severity of trauma or the intensity of the acute-phase response, but was associated with oxidative stress as evidenced by Trolox. Our results demonstrate that changes in microheterogeneity of TTR occur in a substantial number of ICU trauma patients. The diagnostic values of these changes remains to be elucidated. It is speculated that TTR modification may well be the mechanism underlying the morphological manifestation of amyloidose or Alzheimer's diseases in patients surviving multiple trauma.
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Giusti, A., and E. Mastorakos. "Turbulent Combustion Modelling and Experiments: Recent Trends and Developments." Flow, Turbulence and Combustion 103, no. 4 (November 2019): 847–69. http://dx.doi.org/10.1007/s10494-019-00072-6.
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AbstractThe development of better laser-based experimental methods and the fast rise in computer power has created an unprecedented shift in turbulent combustion research. The range of species and quantities measured and the advent of kHz-level planar diagnostics are now providing great insights in important phenomena and applications such as local and global extinction, pollutants, and spray combustion that were hitherto unavailable. In simulations, the shift to LES allows better representation of the turbulent flow in complex geometries, but despite the fact that the grid size is smaller than in RANS, the push towards realistic conditions and the need to include more detailed chemistry that includes very fast species and thin reaction zones emphasize the necessity of a sub-grid turbulent combustion model. The paper discusses examples from current research with experiments and modelling that focus on flame transients (self-excited oscillations, local extinction), sprays, soot emissions, and on practical applications. These demonstrate how current models are being validated by experimental data and the concerted efforts the community is taking to promote the modelling tools to industry. In addition, the various coordinated International Workshops on non-premixed, premixed, and spray flames, and on soot are discussed and some of their target flames are explored. These comprise flames that are relatively simple to describe from a fluid mechanics perspective but contain difficult-to-model combustion problems such as extinction, pollutants and multi-mode reaction zones. Recently, swirl spray flames, which are more representative of industrial devices, have been added to the target flames. Typically, good agreement is found with LES and some combustion models such as the progress variable - mixture fraction flamelet model, the Conditional Moment Closure, and the Transported PDF method, but predicting soot emissions and the condition of complete extinction in complex geometries is still elusive.
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Kovalenko, О. М. "Patient care after surgery: suture care and wound care process." Infusion & Chemotherapy, no. 3.2 (December 15, 2020): 138–40. http://dx.doi.org/10.32902/2663-0338-2020-3.2-138-140.
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Background. A wound is a defect of skin and underlying tissues that can be caused by many factors. Wound care is more than just changing dressings. Different wounds require different approaches and care. Optimal wound care supports the natural healing process in an effective but gentle way. Wounds are classified into acute and chronic, as well as cut, scalped, chopped, stabbed, bruised, torn, bitten, gunshot, and surgical. Surgical wounds are distinguished by the fact that they are applied specifically, for medical or diagnostic purposes, in special aseptic conditions, with minimal tissue trauma, in conditions of anesthesia, with thorough hemostasis and joining of separated anatomical structures with sutures.
Objective. To describe the modern approach to wound care.
Materials and methods. Analysis of literature data on this topic.
Results and discussion. Types of wound healing include primary tension healing, delayed primary tension healing, secondary tension healing, and scab healing. When caring for surgical wounds, primary protection against microorganisms is important. In this case, sterile dressings play an important role, for example, a medical surgical patch with an absorbent pad (Yu-Fix, “Yuria-Pharm”). The pad is characterized by high hygroscopicity, does not stick to the wound and does not leave fibers in the wound. The frequency of dressings changing depends on the healing process and the amount of exudate released from the wound. For festering wounds, the dressing should be changed daily and sometimes more often. Hands and gloves should be worn before bandaging. After removing the gloves, the hands are also treated with an antiseptic (Gorosten, “Yuria-Pharm”, a decamethoxine-based antiseptic). The use of Gorosten in medical institutions for prophylactic purposes is indicated for disinfection of staff hands in order to prevent the spread of transient microflora. Sutures from the surgical wound are removed after the onset of epithelialization, when the wound is covered with a thin protective film. However, in this period there are still wound channels from the threads, so after that it is necessary to treat the wound several times with antiseptic (Dekasan, “Yuria-Pharm”). Signs of local infection of the wound are redness, excess exudate, sometimes – with the addition of pus, odor, pain in the area of injury, fever, edema. Sometimes postsurgical wound suppuration occurs even with proper care due to weak immunity or rejection of surgical suture material. If there is suppuration, it is advisable to switch to dressings with Dekasan and hyperosmolar antibacterial ointments. Unlike 2 % povidone-iodine, which causes severe inhibition of granulation in an open wound, Dekasan does not damage granulation tissue. Surgical treatment, lavage, drainage, antibiotics, laser or ultrasound may also be required. After removing the signs of local inflammation, secondary sutures are applied to the wound or the edges of the wound are connected with the help of adhesive plaster. Before starting the wound care procedure, it is necessary to assess the condition of the wound bed, the nature of the exudate, the condition of the tissues around the wound, pain, wound size. Wound management should involve a multidisciplinary approach. For example, an endocrinologist, a diabetic foot specialist, a purulent surgery surgeon, a vascular surgeon, and a nurse are involved in the treatment of ulcerative defects in patients with diabetes. In the treatment of wounds it is necessary to maintain a humid environment in the wound, maintain a constant temperature without hypothermia, provide adequate drainage and not too tight tamponade, use additional means of healing (eg, unloading the foot in the treatment of foot ulcers in patients with diabetes).
Conclusions. 1. Optimal wound care supports the natural healing process in an effective but gentle way. 2. When caring for surgical wounds, primary protection against the effects of microorganisms is important. 3. Sutures from the surgical wound are removed after the onset of epithelialization, when the wound is covered with a thin protective film. 4. If there is suppuration, it is advisable to switch to dressings with Dekasan and hyperosmolar antibacterial ointments. 5. Wound management should involve a multidisciplinary approach.
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Tkachenko, Victor, Vladimir Lipp, Martin Büscher, Flavio Capotondi, Hauke Höppner, Nikita Medvedev, Emanuele Pedersoli, et al. "Effect of Auger recombination on transient optical properties in XUV and soft X-ray irradiated silicon nitride." Scientific Reports 11, no. 1 (March 4, 2021). http://dx.doi.org/10.1038/s41598-021-84677-w.
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AbstractSpatially encoded measurements of transient optical transmissivity became a standard tool for temporal diagnostics of free-electron-laser (FEL) pulses, as well as for the arrival time measurements in X-ray pump and optical probe experiments. The modern experimental techniques can measure changes in optical coefficients with a temporal resolution better than 10 fs. This, in an ideal case, would imply a similar resolution for the temporal pulse properties and the arrival time jitter between the FEL and optical laser pulses. However, carrier transport within the material and out of its surface, as well as carrier recombination may, in addition, significantly decrease the number of carriers. This would strongly affect the transient optical properties, making the diagnostic measurement inaccurate. Below we analyze in detail the effects of those processes on the optical properties of XUV and soft X-ray irradiated Si$${_3}$$ 3 N$$_4$$ 4 , on sub-picosecond timescales. Si$${_3}$$ 3 N$$_4$$ 4 is a wide-gap insulating material widely used for FEL pulse diagnostics. Theoretical predictions are compared with the published results of two experiments at FERMI and LCLS facilities, and with our own recent measurement. The comparison indicates that three body Auger recombination strongly affects the optical response of Si$${_3}$$ 3 N$$_4$$ 4 after its collisional ionization stops. By deconvolving the contribution of Auger recombination, in future applications one could regain a high temporal resolution for the reconstruction of the FEL pulse properties measured with a Si$${_3}$$ 3 N$$_4$$ 4 -based diagnostics tool.
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Liu, Yaning, Haihang Ye, HoangDinh Huynh, Chen Xie, Peiyuan Kang, Jeffrey S. Kahn, and Zhenpeng Qin. "Digital plasmonic nanobubble detection for rapid and ultrasensitive virus diagnostics." Nature Communications 13, no. 1 (March 30, 2022). http://dx.doi.org/10.1038/s41467-022-29025-w.
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AbstractRapid and sensitive diagnostics of infectious diseases is an urgent and unmet need as evidenced by the COVID-19 pandemic. Here, we report a strategy, based on DIgitAl plasMONic nanobubble Detection (DIAMOND), to address this need. Plasmonic nanobubbles are transient vapor bubbles generated by laser heating of plasmonic nanoparticles (NPs) and allow single-NP detection. Using gold NPs as labels and an optofluidic setup, we demonstrate that DIAMOND achieves compartment-free digital counting and works on homogeneous immunoassays without separation and amplification steps. DIAMOND allows specific detection of respiratory syncytial virus spiked in nasal swab samples and achieves a detection limit of ~100 PFU/mL (equivalent to 1 RNA copy/µL), which is competitive with digital isothermal amplification for virus detection. Therefore, DIAMOND has the advantages including one-step and single-NP detection, direct sensing of intact viruses at room temperature, and no complex liquid handling, and is a platform technology for rapid and ultrasensitive diagnostics.
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Li, Kai, Joakim Laksman, Tommaso Mazza, Gilles Doumy, Dimitris Koulentianos, Alessandra Picchiotti, Svitozar Serkez, et al. "Ghost-imaging-enhanced noninvasive spectral characterization of stochastic x-ray free-electron-laser pulses." Communications Physics 5, no. 1 (July 25, 2022). http://dx.doi.org/10.1038/s42005-022-00962-8.
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AbstractHigh-intensity ultrashort X-ray free-electron laser (XFEL) pulses are revolutionizing the study of fundamental nonlinear x-ray matter interactions and coupled electronic and nuclear dynamics. To fully exploit the potential of this powerful tool for advanced x-ray spectroscopies, a noninvasive spectral characterization of incident stochastic XFEL pulses with high resolution is a key requirement. Here we present a methodology that combines high-acceptance angle-resolved photoelectron time-of-flight spectroscopy and ghost imaging to enhance the quality of spectral characterization of x-ray free-electron laser pulses. Implementation of this noninvasive high-resolution x-ray diagnostic can greatly benefit the ultrafast x-ray spectroscopy community by functioning as a transparent beamsplitter for applications such as transient absorption spectroscopy in averaging mode as well as covariance-based x-ray nonlinear spectroscopies in single-shot mode where the shot-to-shot fluctuations inherent to a self-amplified spontaneous emission (SASE) XFEL pulse are a powerful asset.
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"06/01320 Diagnostic considerations for optical laser-extinction measurements of soot in high-pressure transient combustion environments." Fuel and Energy Abstracts 47, no. 3 (May 2006): 197. http://dx.doi.org/10.1016/s0140-6701(06)81324-x.
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Neupane, Sneha, Vicente Boronat, Derek Splitter, and William P. Partridge. "An improved Method for Determining Transient Fuel Dilution of Oil in an Internal-Combustion Engine Using Laser-Induced Florescence and Multivariate Least Square Calibration." Applied Spectroscopy, March 5, 2021, 000370282199645. http://dx.doi.org/10.1177/0003702821996455.
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An optical diagnostic, based on laser-induced fluorescence (LIF), has been developed for on-engine measurements of real-time fuel dilution of engine oil or fuel in oil (FIO). Fuel dilution of oil is broadly relevant to advancing engine technology including durability, calibration, and catalyst-system management, and believed to promote destructive stochastic pre-ignition (SPI) during high-load engine operations. While standard (e.g., ASTM D3524-90) methods are not capable of real-time transient measurements, the LIF technique resolves transient dilution on the minutes time scale. We have expanded on our original FIO instrument development by introducing an improved analysis based on multivariate least square chemometrics analysis. The measurement uses a fuel dye (180–1300 parts per million, by mass) and monitors for its presence in the oil using 532 nm excitation and LIF. While the original FIO instrument utilized a two-color ratio method for analysis, the improved chemometric analysis uses the fully resolved LIF dye spectra to provide better predictive FIO accuracy (>92%) over a wide FIO range (1.5–14%) typical of engine application. We also investigate the effect of oil temperature on the LIF signal. Limited engine applications for demonstrating and validating the improved FIO instrument are shown, and the related data used to quantify practical detection limit and sensitivity. The improved analysis is insensitive to laser power fluctuation and change in detector integration time, providing an excellent FIO sensitivity (1–2%) and detection limit (0.01 %FIO) over a wide range of loads and injection timings, illustrating this updated approach to be a promising tool for advancing engine technology.
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Ahmad, Irshad. "Study of Shock-processed Titanium Powder in View the Crystal Structure and Microstructure Dimension." Journal of Metallic Material Research 2, no. 2 (October 31, 2019). http://dx.doi.org/10.30564/jmmr.v2i2.1041.
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Titanium powder was rapidly solidified by using shock-wave consolidation technique. The critical parameters were controlled by the instrumented detonics and pin- oscillography. The compacted specimens were investigated for crystal structure and micro structural strengthening by using standard diagnostic techniques. The density of the final product was found to be more than 96% of the theoretical value. X-ray diffraction pattern reveals intact crystalline structure without the presence of any undesired phases. The particle size reduction indicated by XRD was supported by laser diffraction based particle size analyzer. The crystalline structure of the compacted specimen remained intact. No impurity or phase of any other kind was detected. There is no segregation within the compacts. Results from energy dispersive spectroscopy ruled out the possibility of any segregation within the compacts. This high-quenching during rapid solidification minimize chemical segregation and formation of massive phases and hence ensures a homogeneous fine-grained structure. Scanning electron microscopy showed crack-free, voids-free, melt-free, fracture-less compacts of titanium with a unidirectional dendrite orientation without any grain-growth. The particle size of the titanium powder calculated from SEM image found to be ~30μm that supports the earlier observation. Shock-wave consolidation being transient in nature, owing to its short processing time, controlled parameters and high quench-rates proven to be a very helpful technique for obtaining a stable structural and microstrutural products. Hence, SWC technique helped in forming the uniform melt-free, crack-free, voids-free compacts of titanium powder.