检索结果-南通市图书馆

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

引用

Matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt M.Gyrdymov S.Zähter P.Tavana M.M.Günther n.Bukharskii n.Borisenko J.Jacoby X.F.Shen A.Pukhov n.E.Andreev o.n.rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany national Research nuclear University MEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation Moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bright betatron radiation from direct-laseraccelerated electrons at moderate relativistic laser intensity

引用

Matter and Radiation at Extremes 2021年第4期6卷 10-17页

作者： o.n.rosmej X.F.Shen A.Pukhov L.Antonelli F.Barbato M.Gyrdymov M.M.Gunther S.Zahter V.S.Popov n.G.Borisenko n.E.Andreev GSI Helmholtzzentrum fur Schwerionenforschung GmbH Planckstraße164291 DarmstadtGermany Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany Helmholtz Forschungsakademie Hessen fur FAIR(HFHF) Campus Frankfurt am MainMax-von-Laue-Straße 1260438 Frankfurt am MainGermany Heinrich-Heine-University Dusseldorf Universitatsstraße 1DusseldorfGermany York Plasma Institute University of YorkChurch LaneHeslingtonYork YO105DQUnited Kingdom University of Bordeaux CNRSCEACELIAUMR 5107F-33405 TalenceFrance Joint Institute for High Temperatures RASIzhorskaya St.13Bldg.2125412 MoscowRussia Moscow Institute of Physics and Technology(State University) Institutskiy Pereulok 9141700 DolgoprudnyMoscow RegionRussia P.n.Lebedev Physical Institute RASLeninsky Prospekt 53119991 MoscowRussia

Direct laser acceleration(DLA)of electrons in a plasma of near-critical electron density(nCD)and the associated synchrotron-like radiation are discussed for moderate relativistic laser intensity(normalized laser amplitude a0≤4.3)and ps length *** regime is typical of kJ PW-class laser facilities designed for high-energy-density(HED)*** experiments at the PHELIX facility,it has been demonstrated that interaction of a 1019 W/cm2 sub-ps laser pulse with a sub-mm length nCD plasma results in the generation of high-current well-directed superponderomotive electrons with an effective temperature ten times higher than the ponderomotive potential[rosmej et al.,Plasma *** Fusion 62,115024(2020)].Three-dimensional particle-in-cell simulations provide good agreement with the measured electron energy distribution and are used in the current work to study synchrotron radiation from the DLA-accelerated *** resulting x-ray spectrum with a critical energy of 5 keV reveals an ultrahigh photon number of 731011 in the 1–30 keV photon energy range at the focused laser energy of 20 *** simulations of betatron x-ray phase contrast imaging based on the DLA process for the parameters of a PHELIX laser are *** results are of interest for applications in HED experiments,which require a ps x-ray pulse and a high photon flux.

关键词： intensity relativistic critical

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparison of Perovskite Systems Based on AFeo_(3)(A=Ce,La,Y)in Co_(2) Hydrogenation to Co

引用

Transactions of Tianjin University 2024年第4期30卷 337-358页

作者： Anna n.Matveyeva Shamil o.omarov Laboratory of Materials and Processes for Hydrogen Energy Ioff e Institute194021 St.PetersburgRussia

Co_(2) is the most cost-eff ective and abundant carbon resource,while the reverse water-gas reaction(rWGS)is one of the most eff ective methods of Co_(2) *** work presents a comparative study of rWGS activity for perovskite systems based on AFeo_(3)(where A=Ce,La,Y).These systems were synthesized by solution combustion synthesis(SCS)with diff erent ratios of fuel(glycine)and oxidizer(φ),diff erent amounts of nH 4 no_(3),and the addition of alumina or silica as *** techniques,including X-ray diff raction analysis,thermogravimetric analysis,Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy,energy-dispersive X-ray spectroscopy,n 2-physisorption,H_(2) temper-ature-programmed reduction,temperature-programmed desorption of H_(2) and Co_(2),Raman spectroscopy,and in situ FTIR,were used to relate the physicochemical properties with the catalytic performance of the obtained *** specifi c perovskite-containing system(either bulk or supported)has its own optimalφand nH_(4) no_(3) amount to achieve the highest yield and dispersion of the perovskite *** all synthesized systems,bulk SCS-derived La-Fe-o systems showed the highest resistance to reducing environments and the easiest hydrogen desorption,outperforming La-Fe-o produced by solgel combustion(SGC).Co_(2) conversion into Co at 600°C for bulk ferrite systems,depending on the A-cation type and preparation method,follows the order La(SGC)nces in properties between La-Fe-o obtained by the SCS and SGC methods can be attributed to diff erent ratios of oxygen and lanthanum vacancy contributions,hydroxyl coverage,morphology,and free iron oxide *** situ FTIR data revealed that Co_(2) hydrogenation occurs through formates generated under reaction conditions on the bulk system based on La-Fe-o,obtained by the SCS method.γ-Al_(2)o_(3) improves the dispersion of CeFeo_(3) and LaFeo_(3) phases,the specifi c surface area,and the quant

关键词： Perovskites LaFeo_(3) CeFeo_(3) YFeo_(3) Solution combustion synthesis Co_(2) hydrogenation Reverse water–gas reaction(rWGS)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

numerical Simulation of Thermocapillary Convection with Evaporation Induced by Boundary Heating

引用

Fluid Dynamics & Materials Processing 2024年第7期20卷 1667-1686页

作者： o.n.Goncharova V.B.Bekezhanova Altai State University Institute of Mathematics and Information TechnologiesBarnaul656049Russia Institute of Computational Modelling SB RAS Department of Differential Equations of MechanicsKrasnoyarsk660036Russia

The dynamics of a bilayer system filling a rectangular cuvette subjected to external heating is *** influence of two types of thermal exposure on the flow pattern and on the dynamic contact angle is *** particular,the cases of local heating from below and distributed thermal load from the lateral walls are *** simulation is carried out within the frame of a two-sided evaporative convection model based on the Boussinesq approximation.A benzine–air system is considered as reference *** variation in time of the contact angle is described for both heating *** lateral heating,near-wall boundary layers emerge together with strong convection,whereas the local thermal load from the lower wall results in the formation of multicellular motion in the entire volume of the fluids and the appearance of transition regimes followed by a steady-state *** results of the present study can aid the design of equipment for thermal coating or drying and the development of methods for the formation of patterns with required structure and morphology.

关键词： Thermocapillary convection two-phase system numerical modeling contact angle

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

引用

Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria n.Poshina Aleksandra o.Sitnikova natalia n.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the Russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—oSo3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcoH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcoH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%nning electron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

RBC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

引用

Journal of Innovative optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov P.B.Ermolinskiy o.n.Scheglovitova n.n.Sklyankina A.V.Muravyov A.E.Lugovtsov A.V.Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia n.F.Gamaleya national Research Center for Epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State Pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RBCs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RBC properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(no),which is mainly produced by endothelial cells(EC)from L-arginine amino acid in the circulatory *** the mechanisms of the RBC-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced no on RBC aggregation and adhesion to endothelium;(2)the no e®ect on RBC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RBC aggregation and adhesion to a monolayer of EC were studied using optical tweezers(oT).The RBC deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that no increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only no signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RBC aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of no production by ***,data related to L-arginine accumulation by endothelium were obtained:necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,no decreased the RBC-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RBC adhesion to endothelium monolayer with oT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan

引用

Geodesy and Geodynamics 2024年第2期15卷 156-165页

作者： natalya V.Silacheva n.P.Stepanenko o.K.Kurilova A.D.Kudabayeva A.T.Danabayeva Institute of Seismology Ministry of Emergency SituationsAlmaty 050060Kazakhstan

Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the *** regulations are created on the basis of seismic zoning maps of various degrees of detail,developed by our Institute of Seismology using a new methodological approach for *** article is about creating the first normative map of the Detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan *** carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main provisions of Eurocode 8and updated compared with that used in developing maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of *** most thorough and current data accessible for the area under consideration were combined with contemporary analytical *** have been done to not only the databases being used but also the way seismic sources were shown,including active faults *** a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic *** obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s previous ***,because active faults were included and a thoroughly revised catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the *** the west of the territory,acceleration values also increased due to a more accurate consideration of seismotectonic *** maps are the basis for developing new state building regulations of the Republic of Kazakhstan.

关键词： Probabilistic seismic hazard assessment Detailed seismic zoning Peak ground acceleration Microseismical intensity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Machine learning in liver surgery:Benefits and pitfalls

引用

World Journal of Clinical Cases 2024年第12期12卷 2134-2137页

作者： Rafael Calleja Manuel Durán María Dolores Ayllón Ruben Ciria Javier Briceño Hepatobiliary Surgery and Liver Transplantation Unit Hospital Universitario Reina SofíaMaimonides Biomedical Research Institute of CordobaCórdoba 14004Spain

The application of machine learning(ML)algorithms in various fields of hepatology is an issue of ***,we must be cautious with the *** this letter,based on a published ML prediction model for acute kidney injury after liver surgery,we discuss some limitations of ML models and how they may be addressed in the *** the future faces significant challenges,it also holds a great potential.

关键词： Machine learning Liver surgery Artificial intelligence Random forest Prediction model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

引用

nano Materials Science 2024年第2期6卷 193-200页

作者： M.I.Ikim G.n.Gerasimov V.F.Gromov o.J.Ilegbusi L.I.Trakhtenberg n.n.Semenov Federal Research Center for Chemical Physics of RAS MoscowRussia University of Central Florida OrlandoFLUSA Moscow Institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow State University MoscowRussia

The hydrothermal synthesis of In_(2)o_(3)and Ceo_(2)–In_(2)o_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)o_(3),intermediate products In(oH)_(3)and InooH are formed,which are the precursors of stable cubic(c-In_(2)o_(3))and metastable rhombohedral(rh-In_(2)o_(3))phases,respectively.A transition from c-In_(2)o_(3)to rh-In_(2)o_(3)is observed with the addition of Ceo_(2).The introduction of cerium into rh-In_(2)o_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)o_(3).The data on the sensor activity of the composites correlate with XPS results in which Ceo_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)o_(3).The reverse situation is observed in composites based on c-In_(2)o_(3).Compared to In_(2)o_(3)and Ceo_(2)–In_(2)o_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)o_(3)and Ceo_(2).

关键词： Cerium oxide Indium oxide nanocomposite Hydrothermal method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

引用

Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：