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Controlled acceleration of GeV electron beams in an all-optical plasma waveguide

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Light(Science & Applications) 2022年第7期11卷 1535-1541页

作者： Kosta Oubrerie Adrien Leblanc Olena Kononenko Ronan Lahaye Igor A.Andriyash Julien Gautier Jean-Philippe Goddet Lorenzo Martelli Amar TafziKim Ta Phuoc slava smartsev Cédric Thaury LOA CNRSEcole PolytechniqueENSTA ParisInstitut Polytechnique de Paris181 Chemin de la Hunière et des Joncherettes91120 PalaiseauFrance

Laser-plasma accelerators(LPAs)produce electric fields of the order of 100 GV m-1,more than 1000 times larger than those produced by radio-frequency *** uniquely strong fields make LPAs a promising path to generate electron beams beyond the TeV,an important goal in high-energy ***,large electric fields are of little benefit if they are not maintained over a long *** is therefore of the utmost importance to guide the ultra-intense laser pulse that drives the *** very high energies is equally useless if the properties of the electron beam change completely from shot to shot,due to the intrinsic lack of stability of the injection ***-of-the-art laser-plasma accelerators can already address guiding and control challenges separately by tweaking the plasma ***,the production of beams that are simultaneously high quality and high energy has yet to be *** paper presents a novel experiment,coupling laser-plasma waveguides and controlled injection techniques,facilitating the reliable and efficient acceleration of high-quality electron beams up to 1.1 GeV,from a 50 TW-class laser.

关键词： process. acceleration uniquely

Two-color spectroscopy of UV excited ssDNA complex with a single-wall nanotube photoluminescence probe： Fast relaxation by nucleobase autoionization mechanism

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Nano Research 2016年第2期9卷 571-583页

作者： Tetyana Ignatova Alexander Balaeff Michael Blades Ming Zheng: Peter Stoeckl slava V. Rotkin Physics Department Lehigh University 16 Memorial Dr. E. Bethlehem PA 1801S USA NanoScience Technology Center University of Central Florida 12424 Research Parkway Suite 400 Orlando FL 32826 USA National Institute of Standards and Technology 100 Bureau Drive Gaithersburg MD 20899 USA Department of Physics & Astronomy University of Rochester 206 Bausch & Lomb Hall Rochester NY 14627 USA Physics Department Center for Advanced Materials & Nanotechnology and Center for Photonics & Nanoelectronics Lehigh University16 Memorial Dr. E. Bethlehem PA 18015 USA

DNA autoionization is a fundamental process wherein ultraviolet （UV）- photoexcited nucleobases dissipate energy by charge transfer to the environment without undergoing chemical damage. Here, single-wall carbon nanotubes （SWNT） are explored as a photoluminescent reporter for the study of the mechanism and rates of DNA autoionization. Two-color photoluminescence spectroscopy allows separate photoexcitation of the DNA and the SWNTs in the UV and visible range, respectively. A strong SWNT photoluminescence quenching is observed when the UV pump is resonant with the DNA absorption, consistent with charge transfer from the excited states of the DNA to the SWNT. Semiempirical calculations of the DNA-SWNT electronic structure, combined with a Green＇s function theory for charge transfer, show a 20 fs autoionization rate, dominated by hole transfer. Rate-equation analysis of the spectroscopy data confirms that the quenching rate is limited by thermalization of the free charge carriers transferred to the nanotube reservoir. This approach has great potential for monitoring DNA excitation, autoionization, and chemical damage, both in vivo and in vitro.

关键词： single-wall nanotube optical spectroscopy two-color spectroscopy DNA autoionization DNA ultraviolet (UV) excitation quantum-mechanical modeling

Cooling of Granules in Vibrating, Suspended Bed: Engineering Simulation

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Modern Mechanical Engineering 2016年第2期6卷 76-90页

作者： Valery Katz slava Katz SCE—Sami Shamoon College of Engineering Beer-Sheva Israel

Here we suggest an algorithm for calculation of the process parameters and design of a vertical cooler with inclined, gas-permeable blades and with a vibrating, suspended layer of granules on them (Vibrating Fluidized Bed—VFB). The algorithm is based on the use of the equations of heat and material balance, taking into account the influx of moisture into the layer with cold air and dust—as a carryover. Mode entrainment of dust particles and moisture from the VFB is described by using empirical formulas and Π-theorem. To calculate the cooling time of granules a model of the dynamics of a variable mass VFB was built, which linked the geometrical and physical process parameters to a single dependency. An example showed that mass flow of granules of 248 kg/h and a volume flow of air of 646 m3/h with temperature of 30℃ to cool the zeolite granules from 110℃ to 42℃ for 49 s required a vertical apparatus of rectangular shape with four chambers and with volume of 0.2 m3. A comparative analysis of technological parameters of the projected cooler with the parameters of typical industrial apparatuses showed that for all indicators: the cooling time of granules, the flow rate of gas (air) and the heat flow, a 4-chambered, vertical apparatus of rectangular shape with VFB was the most effective.

关键词： Cooling of Granules Vibrating Fluidized Bed Mathematical Model Calculation Algorithm

Theoretical and Experimental Studies of Schottky Diodes that Use Aligned Arrays of Single-Walled Carbon Nanotubes

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Nano Research 2010年第6期3卷 444-451页

作者： Xinning Ho Lina Ye slava V.Rotkin Xu Xie Frank Du Simon Dunham Jana Zaumseil John A.Rogers Department of Materials Science and Engineering Beckman Instituteand Frederick Seitz Materials Research LaboratoryUniversity of Illinois at Urbana-Champaign1304 West Green StreetUrbanaIllinois 61801USA Department of Chemistry University of Science and Technology of ChinaHefei 230026China Department of Physics Lehigh UniversityBethlehemPennsylvania 18015 and Centre for Advanced Materials and NanotechnologyLehigh UniversityBethlehemPennsylvania 18015USA Center for Nanoscale Materials Argonne National LaboratoryArgonneIllinois 60439USA Department of Chemistry University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA Department of Electrical and Computer Engineering Mechanical Science and EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA

We present theoretical and experimental studies of Schottky diodes that use aligned arrays of single-walled carbon nanotubes. A simple physical model, taking into account the basic physics of current rectification, can adequately describe the single-tube and array devices. We show that for as-grown array diodes, the rectification ratio, defined by the maximum-to-minimum-current-ratio, is low due to the presence of metallic-single-walled nanotube (SWNT) shunts. These tubes can be eliminated in a single voltage sweep resulting in a high rectification array device. Further analysis also shows that the channel resistance, and not the intrinsic nanotube diode properties, limits the rectification in devices with channel length up to 10 μm.

关键词： Schottky diodes aligned arrays single-walled carbon nanotubes

Fractal Interpretation of Ultrasonic Crystallization of Solutions

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Journal of Mechanics Engineering and Automation 2016年第1期6卷 53-58页

作者： Valery Katz slava Katz SCE (Shamoon College of Engineering) Beer-Sheva Israel Teva Pharmaceutical Industries Ltd. Kfar Saba Plant Israel

Experiments were performed on the crystallization of a CuSO4 solution upon the action of the temperature gradient with the forming of mono crystals three wedges crystal system （prisms）. We found that the fractal dimension of crystals equals 2.45, which is consistent with the literature data. Crystal growth is represented as the N-rd translation of each side of the crystal lattice with its own speed and with relation to the formation of similar structures--fractals. A mathematical model of ultrasonic crystallization of a CuSO4 solution was proposed. The model is based on the combined use of differential transport equations of momentum, mass, energy and sound waves and a method of similarity and dimensional analysis. The calculated formulas for the concentration of Ccr, the equivalent diameter of the formed crystals dcr and the intensity of internal energy source Ф, associated with the interaction of crystals with the hydro mechanical, heat and sound fields were obtained. Fractal interpretation of ultrasonic crystallization of the CuSO4 solution was made. It was found that on the growth of crystal size d^r directly affects translation N, i.e., an increase in the number of sets of crystals of infinitely small size e, correspond to the size of the crystal lattice. In turn, translation of crystals depends on the geometry of the crystallizer and the physical parameters of external force fields, acting on the CuSO4 solution. A connection of results of the mathematical modeling with the results of fractal analysis of the ultrasonic crystallization of solutions was established.

关键词： Ultrasonic crystallization of solutions physical and mathematical simulation fractal interpretation.

Investigation of Algorithms for VolP Signaling

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Journal of Electrical Engineering 2016年第4期4卷 203-207页

作者： Todorka Georgieva Ekaterina Dimitrova slava Yordanova Telecommunication Department Technical University of Varna Studentska 1 9010 Varna Bulgaria Department of Electronics and Microelectronics Technical University of Varna Studentska 1 Bulgaria Department of Computer Science and Engineering Technical University of Varna Studentska 1 Bulgaria

This paper discusses issues regarding the operation of algorithms for VolP （voice over intemet protocol） signaling. The resulting data include jitter, packet delays, delays related to signalization, distribution of ... 详细信息

关键词： Codec packet signalization VoIP.

Analysis of the Parameters of the Ore RestorationFurnaces for Equal Power on the Shelf-Baking andGraphitized Electrodes

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Journal of Energy and Power Engineering 2016年第12期10卷 786-791页

作者： Vladimir Kldiashvili Tamaz Natriashvili slava Mebonia Aleksandre Shermazanashvili R. Dvali Institute of Machine Mechanics 10 Mindeli str. Tbilisi 0186 Georgia

Results of calculation of the power indicators of the ore restoration arc furnaces with the set power of 10.5 MVA workingon are given as on the self-baking also on the graphitized electrodes. It is established that despite high cost of the graphitizedelectrodes in comparison with the self-baking electrodes, power parameters much more improve. Besides, the natural power factorincreases, melting time decreases and that the most important the furnace turns out compact, convenient for service, building of thegraphitized electrodes is carried out for a small period, and also the number of service personnel is reduced. We propose a newdesign scheme of low-voltage circuit for the arc furnace according to the scheme ＂a triangle on the electrodes＂ designed in athree-bifilar version, in which more complete symmetry is gained by means of the crosspieces forming a triangle directly at theelectrode arms. In the proposed scheme, the current-carrying tubes that have different polarity are located on the same arm that leadsto further reduction in low-voltage circuit inductance. The application of this scheme allows for reducing reactive and activeresistances of low-voltage circuits by 2.5-3 times and 15-20%, respectively, as well as for shortening the heat, reducing specificenergy consumption and increasing the installation power factor.

关键词： Power indicators, ore restoration, arc furnace, self-baking, graphitized electrode, low-voltage circuit, reactive resistance,bifilar arrangement of tires.

Femtosecond laser-assisted fabrication of piezoelectrically actuated crystalline quartz-based MEMS resonators

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Microsystems & Nanoengineering 2023年第2期9卷 295-306页

作者： John Linden Neta Melech Igor Sakaev Ofer Fogel slava Krylov David Nuttman Zeev Zalevsky Marina Sirota Department of Engineering Bar lan UniversityRamat GanIsral Research and Incubation ERCKLAYavneIsrael School of Mechanical Engineering Faculty of EngineeringTel-Aviv UniversityTel AvivIsrael Engineering Department TAMAMIAlYehudIsrael

A novel technology for the precise fabrication of quartz resonators for MEMS applications is *** approach is based on the laser-induced chemical etching of *** main processing steps include femtosecond UV laser treatment of a Cr-Au-coated Z-cut alpha quartz wafer,followed by wet *** laser-patterned Cr-Au coating serves as an etch mask and is used to form electrodes for piezoelectric *** fabrication approach does not alter the quartz's crystalline structure or its piezo-electric *** formation of defects,which is common in laser micromachined quartz,is prevented by optimized process parameters and by controlling the temporal behavior of the laser-matter *** process does not involve any lithography and allows for high geometric design *** configurations of piezoelectrically actuated beam-type resonators were fabricated using relatively mild wet etching conditions,and their functionality was experimentally *** devices are distinguished from prior efforts by the reduced surface roughness and improved wall profiles of the fabricated quartz structures.

关键词： quartz Femto piezoelectric

Immune Reactive Ezrin Surface Area Increases in Glomerular Podocytes of STZ Diabetic Rats Precede Their Detachment, Is Prevented by Phlorizin But Not by Insulin

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Journal of Diabetes Mellitus 2020年第2期10卷 27-40页

作者： slava Malatiali Issam Francis Musleeha Chesor Gavin Welsh Moin Saleem Mario Barac-Nieto Departments of Physiology Faculty of Medicine Kuwait University Safat Kuwait Pathology Faculty of Medicine Kuwait University Safat Kuwait University of Bristol Pediatric Nephrology Bristol UK Retired 9443 Hickory Limb Colusmbia MD USA

Glomerular tuft immune reactive Ezrin surface area (EzA) and fraction of EzA to total glomerular tuft area significantly increased, indicating podocyte growth, rounding and altered cytoskeletal interactions at 1 week of STZ diabetes. Podocyte number per glomerulus (WT1+ nuclei) did not change indicating no detachment, but density decreased due to tuft hypertrophy. Treatment with PLZ or Insulin for one week, prevented increase in proteinuria and hyperglycemia but not the decrease in podocyte density. PLZ but not Insulin prevented increase in ezrin positive area in glomeruli and per podocyte. In podocytes in culture neither 25 mM glucose with or without PLZ (2.5 or 25 uM) altered Ezrin expression measured in western blots. In summary, the Ezrin positive glomerular surface area increase seen after 1 week of STZ diabetes, reflects altered podocyte morphology and cytoskeletal interactions, prevented by PLZ but not by insulin. Ezrin area increase preceded podocyte detachment and in podocytes in culture is not associated with increases in podocyte Ezrin protein expression. It is a likely precursor of shape changes in podocytes and of alterd interactions with basement membrane that contribute to detachment and thickening. Glomerular capillary tuft hypertrophy and reduced podocyte density persisted despite PLZ or insulin treatments, independently of levels of glycemia and of proteinuria.

关键词： Diabetes. Hyperglycemia Glomerular Hypertrophy Phlorizin Podocyte Density Ezrin