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英美国家活性污泥处理法的发展

环境科学与管理 1990年第1期 56-59页

作者： m.j.赫瑞王琦张义生

关键词：曝气池 DO 运行费用曝气器水池污水处理设备机械曝气活性污泥处理空气扩散器

粉末冶金Al-5.6Zn-2mg合金在热压缩过程中加工硬化特性及本构模型的比较

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journal of Central South University 2024年第2期31卷 346-368页

作者： KATIKA Harikrishna DAmODA R.K. DAVIDSON m.j. SEETHARAm R. KASAGANI Veera Venkata Nagaraju Department of mechanical Engineering National Institute of TechnologyWarangal 506004India Department of mechanical Engineering The Indian Institute of Information Technology Design and ManufacturingKurnool 518007India

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的... 详细信息

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的相关性。使用了四个本构模型,Arrhenius模型、改进的johnson-Cook模型(mjC)、改进的Zerilli-Armstrong模型(mZA)和开发的人工神经网络(ANN)。结果表明,ANN型模型和Arrhenius模型的相对误差的绝对平均值最低,分别为0.486%和3.36%,mZA型模型和mjC型模型的相对误差的绝对平均值较高,分别为8.84%和3.93%。由于Arrhenius模型能够处理各种因素之间的非线性关系,因此它被认为是最合适的预测模型,但在材料性质未知或实验数据有限的情况下,mjC模型可能是一种更简单的替代方法。mZA模型不适合估计热压缩时的流变应力。此外,训练最好的神经网络模型的预测性能最好,相对误差的绝对平均值为0.486%,R值为0.99。

关键词：加工硬化速率曲线本构建模热压缩 EBSD分析流变曲线

黏声波方程波场模拟的通用格式自适应系数频域有限差分方法

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地球物理学报 2024年第2期67卷 654-669页

作者：徐文豪巴晶 j.m.Carcione 朱鹤松河海大学地球科学与工程学院南京211100 National Institute of Oceanography and Applied Geophysics-OGS Borgo Grotta Gigante 42/cTriesteSgonico 34010Italy

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency domain,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格... 详细信息

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency domain,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格点数小于4时误差较大.通过令FDFD系数随一个波长内的网格点数自适应从而提高FDFD方法的精度,本文针对黏声波波场模拟发展了一种适用于不同空间采样间隔之比的通用格式自适应系数FDFD方法.同时,为了验证自适应系数FDFD方法对一般黏声波模型的有效性,本文针对三个典型的黏声波模型,分别采用解析解和基于高阶FDFD的参考解验证了所提出方法的有效性.本方法的FDFD格式通过在传统的二阶FDFD格式的基础上引入相关校正项得到,其中校正项按网格点与中心点的距离进行分类选取,同时校正项对应的自适应FDFD系数不仅和空间采样间隔之比相关,还和一个波长内的采样点数相关.所需的自适应FDFD系数可通过声波方程的数值频散关系和查找表高效给出.数值频散分析表明,在空间采样间隔相等或不等的情况下,以相速度误差不超过1%为标准,通用格式自适应系数FDFD方法所需的一个波长内的采样点数均小于2.5.数值模拟实验表明,对于不同的空间采样间隔之比,相对于常用的二阶五点FDFD方法和优化九点FDFD方法,通用格式自适应系数FDFD方法均可在相似的计算量和内存需求下,有效提高黏声波模拟的精度.

关键词：黏声波频域有限差分自适应系数波场模拟通用格式

Laser processing effects on Ti−45Nb alloy surface,corrosive and biocompatible properties

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Transactions of Nonferrous metals Society of China 2024年第8期34卷 2533-2551页

作者： I.CVIjOVIĆ-ALAGIĆ S.LAKETIĆ m.mOmČILOVIĆ j.CIGANOVIĆ Đ.VELjOVIĆ j.BAjAT V.KOjIĆ m.RAKIN Vinča Institute of Nuclear Sciences-National Institute of the Republic of Serbia University of BelgradeP.O.Box 52211001 BelgradeSerbia Faculty of Technology and metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Oncology Institute of Vojvodina Faculty of MedicineUniversity of Novi SadPut Dr Goldmana 421204 Sremska KamenicaSerbia

The Ti−45Nb(wt.%)alloy properties were investigated in relation to its potential biomedical *** surface modification was utilized to improve its performance in biological *** a result of the laser treatment,(Ti,Nb)O scale was formed and various morphological features appeared on the alloy *** electrochemical behavior of Ti−45Nb alloy in simulated body conditions was evaluated and showed that the alloy was highly resistant to corrosion deterioration regardless of additional laser surface modification ***,the improved corrosion resistance after laser treatment was evident(the corrosion current density of the alloy before laser irradiation was 2.84×10^(−8)A/cm^(2),while that after laser treatment with 5 mj was 0.65×10^(−8)A/cm^(2))and ascribed to the rapid formation of a complex and passivating bi-modal surface oxide *** cytotoxicity and effects of the Ti−45Nb alloy laser surface modification on the mRC-5 cell viability,morphology,and proliferation were also *** Ti−45Nb alloy showed no cytotoxic ***,cells showed improved viability and adherence to the alloy surface after the laser irradiation *** highest average cell viability of 115.37%was attained for the alloy laser-irradiated with 15 *** showed that the laser surface modification can be successfully utilized to significantly improve alloy performance in a biological environment.

关键词： Ti−45Nb alloy laser surface scanning electrochemical properties biocompatibility cell morphology

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miniSCIDOm: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino m.Reimold E.Beyreuther F.-E.Brack F.Kroll j.Pawelke j.D.Schilz m.Schneider U.Schramm m.E.P.Umlandt K.Zeil T.Ziegler j.metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOm detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

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

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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

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

A multi-shot target wheel assembly for high-repetition-rate, laser-driven proton acceleration

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High Power Laser Science and Engineering 2024年第2期12卷 87-94页

作者： j.Penas A.Bembibre D.Cortina-Gil L.martin A.Reija C.Ruiz m.Seimetz A.Alejo j.Benlliure Instituto Galego de Fisica de Altas Enerxias Universidade de Santiago de CompostelaSantiago de CompostelaSpain Laboratorio Laser de Aceleracion y Aplicaciones RIAIDTUniversidade de Santiago de CompostelaSantiago de CompostelaSpain Instituto Universitario de Física Fundamental y matematicas y Dpto.de Didactica de la matematica y de las Ciencias Experimentales Universidad de SalamancaSalamancaSpain Instituto de Instrumentación para Imagen molecular(I3m) CSIC-Universitat Politecnica de ValenciaValenciaSpain

A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are *** assembly is based on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted on a 3D motorized stage to allow rapid replenishment and alignment of the target material between laser *** automatic alignment procedure consists of a detailed mapping of the impact positions at the target surface prior to the irradiation that ensures stable operation of the target,which alongside the purpose-built design of the target wheel,enables operation at rates up to 10 *** and continuous laser-driven proton acceleration at 10 Hz is demonstrated,with observed cut-off energy stability about 15%.

关键词： high repetition rate laser-plasma acceleration multi-shot operation proton source target assembly

辣椒素治疗神经病理性疼痛:4周后轴突反射血管舒张与疼痛减轻相关

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中国疼痛医学杂志 2024年第4期30卷 251-254页

作者： Sendel m Dunst A Forsten pointer j 贺婷(译) 郑拥军(校) 不详复旦大学附属华东医院

辣椒素是瞬时受体电位香草酸亚型1(transient receptor potential vanilloid 1,TRPV1)的激动剂,用于外周神经病理性疼痛的局部治疗。其作用机制是皮肤痛觉感受器可逆的去功能化和变性及随后的再生。该研究假设伤害性传入的一个亚类,肽... 详细信息

辣椒素是瞬时受体电位香草酸亚型1(transient receptor potential vanilloid 1,TRPV1)的激动剂,用于外周神经病理性疼痛的局部治疗。其作用机制是皮肤痛觉感受器可逆的去功能化和变性及随后的再生。该研究假设伤害性传入的一个亚类,肽能血管活性伤害感受器的功能加速恢复是辣椒素镇痛的潜在原因。在非干预性探索性试验中,23名患有外周神经病理性疼痛的病人接受了1次局部高浓度辣椒素治疗。评估基线疼痛等级、共病和生活质量。在受影响的皮肤中进行功能性激光散斑对比分析(热诱发神经源性血管舒张以评估肽能伤害感受器的功能特性)和定量感觉测试。治疗4周后,再次进行功能性激光散斑对比分析和问卷调查。在第2、10和12周进行电话随访。局部辣椒素治疗诱导疼痛强度显著降低,最大值出现在第4周。同时,热诱发的神经源性血管舒张平均值与治疗前相似。一半的病人不仅显示出功能恢复,而且显示出血管舒张的改善,表明神经纤维的再生。在第4周,热诱发的神经源性血管扩张改善病人比恶化的病人疼痛减轻更多。血管舒张程度与疼痛减轻显著相关。表明肽能感受器的再生可能是辣椒素诱导镇痛的机制,辣椒素对这些纤维的疾病缓解作用在应用4周后已经发生。

关键词：伤害感受器痛觉感受器疼痛减轻血管舒张辣椒素神经病理性疼痛激光散斑血管扩张