检索结果-南通市图书馆

Volumetric changes in the focal areas of seismic events corresponding to destress blasting

International journal of Mining Science and Technology 2019年第4期29卷 541-547页

作者： P.Konicek j.schreiber L.Nazarova Department of Geomechanics and Mining Research Institute of Geonics of the Czech Academy of SciencesOstrava 70800Czech Republic Laboratory of Mining Informatics Chinakal Institute of Mining of the Siberian Branch of the Russian Academy of ScienceNovosibirsk 630091Russia

The typical development of total volumetric change in the focal areas of seismic events,corresponding to destress blasting,is characterized as an explosive phase followed by an implosive phase and with alternating additional phases following on from *** a few cases,a non-typical development of volumetric change was identified,where the first phase was implosive and the second phase,*** development is mainly typical for induced seismic events recorded during mining,not for destress *** events were recorded during longwall mining in the Czech part of the Upper Silesian Coal Basin,where the destress blasting technique is used as a rockburst prevention active *** source processes in the focal areas of selected seismic events were analyzed by the seismic moment tensor inversion method,as well as by studying geomechanical rock mass conditions at the localities of the seismic *** main goal of the analysis was to attempt to identify the reasons for non-typical development of volumetric changes in these *** changes were analyzed for seismic events with energy greater than 104 j,recorded in the period of time from 1993 to 2009(1109 events).80%(891)of the recorded seismic events were induced seismic events that were registered during longwall mining and 20%(218)corresponded to destress blasting *** shows that the main reason for the non-typical development of volumetric changes in the focal areas of seismic events is an association with destress blasting in the rock mass,which is very close to rock mass *** detonation of explosives in boreholes,which would dominate the first phase of volumetric changes,probably obscured stress release in the rock mass,as manifested in the first implosion phase of the volumetric changes in this case.

关键词： Destress blasting Seismic event Volumetric changes Stress release

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

Optimization of relativistic laser–ion acceleration

引用

High Power Laser Science and Engineering 2014年第4期2卷 74-85页

作者： j.schreiber F.Bell Z.Najmudin Fakultt fr Physik Ludwig-Maximilians-Universitt Mnchen Am Coulombwall 1D-85748 Garching Germany Max-Planck-Institut fr Quantenoptik Hans-Kopfermann-Str.1D-85748 Garching Germany The john Adams Institute Blackett Laboratory Imperial College LondonLondon SW7 2AZ United Kingdom

Experiments have shown that the ion energy obtained by laser–ion acceleration can be optimized by choosing either the appropriate pulse duration or the appropriate target thickness. We demonstrate that this behavior can be described either by the target normal sheath acceleration model of schreiber et al. or by the radiation pressure acceleration model of Bulanov and coworkers. The starting point of our considerations is that the essential property of a laser system for ion acceleration is its pulse energy and not its intensity. Maybe surprisingly we show that higher ion energies can be reached with reduced intensities.

关键词： laser–ion acceleration relativistic laser plasma interaction

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

Ion-bunch energy acoustic tracing by modulation of the depth-dose curve

引用

High Power Laser Science and Engineering 2023年第3期11卷 86-93页

作者： A.Praßelsperger F.Balling H.-P.Wieser K.Parodi j.schreiber Fakultät für Physik Ludwig-Maximilians-Universität MünchenGarchingGermany

Characterizing exact energy density distributions for laser-accelerated ion bunches in a medium is challenging due to very high beam intensities and the electro-magnetic pulse emitted in the laser-plasma ***-bunch energy acoustic tracing allows for reconstructing the spatial energy density from the ionoacoustic wave generated upon impact in *** have extended this approach to tracing ionoacoustic modulations of broad energy distributions by introducing thin foils in the water reservoir to shape the acoustic waves at distinct points along the depth-dose ***,we present first simulation studies of this new detector and reconstruction approach,which provides an online read-out of the deposited energy with depth within the centimeter range behind the ion source of state-of-the-art laser-plasma-based accelerators.

关键词： ion-bunch energy acoustic tracing ion detector ionoacoustics laser-ion acceleration

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

Ion-bunch energy acoustic tracing by modulation of the depth-dose curve

引用

High Power Laser Science and Engineering 2023年第3期 90-97页

作者： A.Pra?elsperger F.Balling H.-P.Wieser K.Parodi j.schreiber Fakult?t für Physik Ludwig-Maximilians-Universit?t München

Characterizing exact energy density distributions for laser-accelerated ion bunches in a medium is challenging due to very high beam intensities and the electro-magnetic pulse emitted in the laser±plasma interaction. Ion-bunch energy acoustic tracing allows for reconstructing the spatial energy density from the ionoacoustic wave generated upon impact in water. We have extended this approach to tracing ionoacoustic modulations of broad energy distributions by introducing thin foils in the water reservoir to shape the acoustic waves at distinct points along the depth-dose curve. Here, we present first simulation studies of this new detector and reconstruction approach, which provides an online read-out of the deposited energy with depth within the centimeter range behind the ion source of state-of-the-art laser-plasma-based accelerators.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Three-dimensional acoustic monitoring of laser-accelerated protons in the focus of a pulsed-power solenoid lens

引用

High Power Laser Science and Engineering 2023年第3期11卷 57-63页

作者： S.Gerlach F.Balling A.K.Schmidt F.E.Brack F.Kroll j.Metzkes-Ng M.Reimold U.Schramm M.Speicher K.Zeil K.Parodi j.schreiber Fakultät für Physik Ludwig-Maximilians-Universität MünchenGarchingGermany Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany

The acoustic pulse emitted from the Bragg peak of a laser-accelerated proton bunch focused into water has recently enabled the reconstruction of the bunch energy *** adding three ultrasonic transducers and implementing a fast data analysis of the filtered raw signals,I-BEAT(Ion-Bunch Energy Acoustic Tracing)3D now provides the mean bunch energy and absolute lateral bunch position in real-time and for individual *** changes in energy spread and lateral bunch size can also be *** experiments at DRACO with proton bunch energies between 10 and 30 MeV reveal sub-MeV and sub-mm *** addition to this 3D bunch information,the signal strength correlates also with the absolute bunch particle number.

关键词： ion diagnostics ionoacoustics laser-driven plasma source laser-ion acceleration

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

Target fabrication for laser-ion acceleration research at the Technological Laboratory of the LMU Munich

引用

Matter and Radiation at Extremes 2019年第3期4卷 25-31页

作者： j.Szerypo W.Ma G.Bothmann D.Hahner M.Haug P.Hilz Ch.Kreuzer R.Lange S.Seuferling M.Speicher F.Stehr S.Stork P.G.Thirolf j.schreiber H.-F.Wirth Fakultat fur Physik Ludwig-Maximilians-Universitat MunchenD-85748 GarchingGermany State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Helmholtz-Institut jena Frobelstieg 307743 JenaGermany

The Technological Laboratory of LMU Munich supplies various types of solid-state target for laser plasma experiments at the Centre for Advanced Laser Applications in *** main focus here is on the production of free-standing,thin foil targets,such as diamond-likecarbon foils,carbon nanotube foams(CNFs),plastic,and gold *** presented methods comprise cathodic arc deposition for DLC targets,chemical vapor deposition for CNFs,a droplet and spin-coating process for plastic foil production,as well as physical vapor deposition that has been optimized to provide ultrathin gold foils and tailored sacrifice *** paper reviews our current capabilities,which are a result of a close collaboration between target production processes and experiment,using high-power chirped pulse amplification laser systems over the past eight years.

关键词： acceleration laser coating

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

Non-Maxwellian electron distributions resulting from direct laser acceleration in near-critical plasmas

引用

Matter and Radiation at Extremes 2016年第1期1卷 82-87页

作者： T.Toncian C.Wang E.McCary A.Meadows A.V.Arefiev j.Blakeney K.Serratto D.Kuk C.Chester R.Roycroft L.Gao H.Fu X.Q.Yan j.schreiber I.Pomerantz A.Bernstein H.Quevedo G.Dyer T.Ditmire B.M.Hegelich Department of Physics University of TexasAustinTX78712USA State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing100871China Fakultat fur Physik Ludwig-Maximilians-UniversityMunichGermany

The irradiation of few-nm-thick targets by a finite-contrast high-intensity short-pulse laser results in a strong pre-expansion of these targets at the arrival time of the main *** targets decompress to near and lower than critical densities with plasmas extending over few micrometers,*** *** interaction of the main pulse with such a highly localized but inhomogeneous target leads to the generation of a short channel and further self-focusing of the laser *** at the Glass Hybrid OPCPA Scaled Test-bed(GHOST)laser system at University of Texas,Austin using such targets measured non-Maxwellian,peaked electron distribution with large bunch charge and high electron density in the laser propagation *** results are reproduced in 2D PIC simulations using the EPOCH code,identifying direct laser acceleration(DLA)[1]as the responsible *** is the first time that DLA has been observed to produce peaked spectra as opposed to broad,Maxwellian spectra observed in earlier experiments[2].This high-density electrons have potential applications as injector beams for a further wakefield acceleration stage as well as for pump-probe applications.

关键词： Direct laser acceleration Electron acceleration Near critical plasmas PIC simulations

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

Insights from an academic endeavor into central nervous system drug discovery

引用

Neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An M.Voets Tim Vanmierlo Rudy schreiber BIOMED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and Neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University MS Center(UMSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in modern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(Mazzucato,2013).

关键词： academic approval consequences

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

The free-electron laser FLASH

引用

High Power Laser Science and Engineering 2015年第3期3卷 28-40页

作者： Siegfried schreiber Bart Faatz Deutsches Elektronen-Synchrotron

FLASH at DESY, Hamburg, Germany is the first free-electron laser(FEL) operating in the extreme ultraviolet(EUV)and soft x-ray wavelength range. FLASH is a user facility providing femtosecond short pulses with an unprecedented peak and average brilliance, opening new scientific opportunities in many disciplines. The first call for user experiments has been launched in 2005. The FLASH linear accelerator is based on TESLA superconducting technology, providing several thousands of photon pulses per second to user experiments. Probing femtosecond-scale dynamics in atomic and molecular reactions using, for instance, a combination of x-ray and optical pulses in a pump and probe arrangement,as well as single-shot diffraction imaging of biological objects and molecules, are typical experiments performed at the facility. We give an overview of the FLASH facility, and describe the basic principles of the accelerator. Recently,FLASH has been extended by a second undulator beamline(FLASH2) operated in parallel to the first beamline, extending the capacity of the facility by a factor of two.

关键词： bunch compression free-electron laser high-gain FEL process photo injector SASE superconducting accelerator undulator

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

Heavy rockbursts due to longwall mining near protective pillars:A case study

引用

International journal of Mining Science and Technology 2018年第5期28卷 799-805页

作者： Petr Konicek jan schreiber Department of Geomechanics and Mining Research Institute of Geonics Czech Academy of Science

Rockburst represents a very dangerous phenomenon in deep underground mining in unfavourable conditions such as great depth, high horizontal stress, proximity of important tectonic structures, and unmined pillars. The case study describes a recorded heavy rockburst in the Czech part of the Upper Silesian Coal Basin, which occurred during longwall mining near the protective pillar. The artificial dividing of geological blocks and creation of mining protective pillars(shaft pillars, crosscut pillars etc.) is a dangerous task in light of rockbursts occurring mainly due to overstressing of remaining pillars. A simple model of this situation is presented. Natural and mining conditions are analysed and presented in detail as well as registered seismicity during longwall mining in the area. Recorded rockbursts in the area of interest are described and their causes discussed. Many rockbursts near protective pillars were recorded in this mining region. Methodical instructions for rockburst prevention in proximity of protective pillars as well as for gates driving were devised based on the evaluation of rockburst causes. The paper presents these principles for prevention.

关键词： Rockburst Rockburst prevention Hardcoal longwall mining Induced seismicity Protective pillar

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：