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南昌大学学报(工科版) 1980年第1期 59-73页

作者： kanwar k.kapur ,biilly j.hartz ,由敬舜

引言在土木、机械和航空结构的许多设计中,矩形板的临界屈曲荷载是一个重要因素。由于压缩、剪切和弯曲荷载引起板的屈曲情况,已被以前的研究人员广泛地讨论过,他们的工作已被Gpard和Becker作了充分地概括。

关键词：系数矩阵方程己知临界荷载有限单元法

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

Fe_(3)O_(4)对黄铜矿在酸性硫酸铁溶液中铜溶解氧化还原反应的影响

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1965-1975页

作者： kolela j NYEMBWE Elvis FOSSO-kANkEU Frans WAANDERS Martin MkANDAWIRE Didier k NYEMBWE Bhekie B MAMBA Water Pollution Monitoring and Remediation Initiatives Research Group School of Chemical and Minerals EngineeringFaculty of EngineeringNorth-West UniversityPotchefstroomSouth Africa Department of Mining Engineering College of Science Engineering and TechnologyUniversity of South AfricaFlorida Science CampusJohannesburgSouth Africa Department of Metallurgy Faculty of Engineering and Built EnvironmentUniversity of JohannesburgDoornfonteinJohannesburgSouth Africa Department of Chemistry School of Science and TechnologyCape Breton UniversityCanada School of Mining Metallurgy and Chemical EngineeringFaculty of Engineering and the Built EnvironmentUniversity of JohannesburgJohannesburgSouth Africa Institute for Nanotechnology and Water Sustainability College of Science Engineering and TechnologyUniversity of South AfricaFlorida Science CampusJohannesburgSouth Africa

由于钝化层的形成,黄铜矿(CuFeS_(2))在氧化条件下浸出通常具有溶解速率缓慢的特点。为了将黄铜矿浸出过程中的钝化效应降至最低并提高铜的回收率,研究了CuFeS_(2)在不同pH值(1.0、1.5和1.8)和温度(25和50℃)条件下浸出时,向Fe_(2)(SO_(... 详细信息

由于钝化层的形成,黄铜矿(CuFeS_(2))在氧化条件下浸出通常具有溶解速率缓慢的特点。为了将黄铜矿浸出过程中的钝化效应降至最低并提高铜的回收率,研究了CuFeS_(2)在不同pH值(1.0、1.5和1.8)和温度(25和50℃)条件下浸出时,向Fe_(2)(SO_(4))_(3)−H_(2)SO_(4)浸出剂中添加磁铁矿(Fe_(3)O_(4))对铜溶解速率的影响。结果表明,溶液pH值、电位和温度在溶解过程中起着关键作用。在pH 1.8、50℃和400 mV的条件下,Fe_(3)O_(4)−CuFeS_(2)混合体系中铜的回收率达到最大值(70%),而未添加Fe_(3)O_(4)时,CuFeS_(2)中铜的回收率较低(48%)。添加Fe_(3)O_(4)有助于维持较高的氧化还原值。添加Fe_(3)O_(4)还使活化能从79.04 kj/mol降低到53.69 kj/mol。这表明,当Fe_(3)O_(4)存在时,由于形成了更易溶解的中间体斑铜矿(Cu_(5)FeS_(4))和辉铜矿(Cu_(2)S),CuFeS_(2)更易被氧化。两种溶解过程都受到矿物表面的化学控制。此外,对浸出残渣的矿物学分析表明,当无Fe_(3)O_(4)存在时,作为表面钝化物的黄钾铁矾浓度较高。因此,添加Fe_(3)O_(4)减少了钝化层的形成,提升了铜的回收率。

关键词：黄铜矿溶解磁铁矿电偶钝化

Cytomegalovirus Transverse Myelitis Secondary to Influenza Infection and Early Recovery:A Case Report

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Infectious Diseases & Immunity 2024年第1期4卷 41-42页

作者： jill S.Bhavsar Lekhini k.Fultariya Poojan j.Prajapati Archi k.Dhamelia jaime E.Campos Department of Infectious Disease Hialeah HospitalMiamiFL(affiliated with HerbertWertheim College of MedicineFlorida International University)33013USA

Immunosuppression can lead to opportunistic infections in a *** evidence of viral infections causing immunosuppression in a host for a transient period is gaining *** order to prolong their stay in the human body,viruses affect the human immune systemin various *** viral infections such as influenza can lead to transient lymphocytopenia,which lays the groundwork for more dangerous opportunistic ***(CMV)infection is a rare cause of inflammatory *** present the case of a patient with an influenza infection who progressed to severe acute respiratory distress syndrome,methicillin-resistant Staphylococcus aureus necrotizing pneumonia,and idiopathic lymphocytopenia with a CD4 count of 61 perμL on *** 2 weeks,the patient developed complete flaccid paralysis with sensory and autonomic *** his polymerase chain reaction results of cerebrospinal fluid and blood test were positive for CMV infection,he was treated with high doses of steroids and ganciclovir *** to early diagnosis and intervention,the patient was able to recover in 2 months with only minimal residual ***,this case stresses on the importance of looking out for opportunistic infections in patients affected by severe viral infections for their early recovery.

关键词： Influenza,Human Lymphocytopenia Transverse myelitis Case report

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

1991—2020年暖季河套灌区强对流天气主要流型及环境参量特征分析

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沙漠与绿洲气象 2024年第2期18卷 76-82页

作者：张玉荣姚晓娟白舜耀赵明明巴彦淖尔市气象局内蒙古临河015000 内蒙古自治区气象局内蒙古呼和浩特010000

利用常规气象观测资料、区域自动站观测资料及ERA5再分析资料,对河套灌区1991—2020年542个冰雹个例和281个短时强降水个例主要流型及环境参量特征进行分析。结果显示:(1)短时强降水天气主要有新疆低槽(涡)、东北冷涡、蒙古冷涡、西南气... 详细信息

利用常规气象观测资料、区域自动站观测资料及ERA5再分析资料,对河套灌区1991—2020年542个冰雹个例和281个短时强降水个例主要流型及环境参量特征进行分析。结果显示:(1)短时强降水天气主要有新疆低槽(涡)、东北冷涡、蒙古冷涡、西南气流4类影响系统,冰雹天气主要有蒙古冷涡、西北气流、东北冷涡、巴尔喀什湖冷涡4类影响系统;(2)河套灌区短时强降水和冰雹各关键参数预报阈值均有差异,最低阈值的建议值采用箱线图25%百分位值,其中△T_(850-500)分别为26和33℃,k指数均值分别为27和35℃,CAPE均值分别为515和405 j·kg^(-1),0~6 km垂直风切变均为7×10^(-3)s^(-1),0℃层高度均值分别为4656和4069 m,-20℃层高度均值分别为8070和7054 m;(3)冰雹需要更大的k指数、△T_(850-500)以及更强的低层暖空气,同时冰雹有更低的0℃层和-20℃层高度,较低的0℃层高度可以防止冰雹下落过程融化。此外,下垫面因子对不同强对流天气的影响程度也不同,海拔高度是影响河套灌区冰雹分布的主要因素。

关键词：强对流天气短时强降水冰雹物理量

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： k.D.james j.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Use of donepezil for neurocognitive recovery after brain injury in adult and pediatric populations:a scoping review

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Neural Regeneration Research 2024年第8期19卷 1686-1695页

作者： Avery L.Miller Nathan k.Evanson j.Michael Taylor University of Cincinnati College of Medicine CincinnatiOHUSA Department of Pediatrics University of CincinnatiCincinnatiOHUSA Department of Neurology and Rehabilitation Medicine University of CincinnatiCincinnatiOHUSA Division of Pediatric Rehabilitation Medicine Cincinnati Children’s Hospital Medical CenterCincinnatiOHUSA Division of Neurology Cincinnati Children’s Hospital Medical CenterCincinnatiOHUSA

There are few pharmacologic options for the treatment of cognitive deficits associated with traumatic brain injury in pediatric *** inhibitors such as donepezil have been evaluated in adult patients after traumatic brain injury,but relatively less is known about the effect in pediatric *** goal of this review is to identify knowledge gaps in the efficacy and safety of acetylcholinesterase inhibito rs as a potential a djuvant treatment fo r neurocognitive decline in pediatric patients with traumatic brain *** queried PubMed to identify literature published from database inception thro ugh june 2023 desc ribing the use of donepezil in young adult traumatic brain injury and pediatric patients with predefined *** on preselected search criteria,340 unique papers we re selected for title and abstra ct ***-two reco rds were reviewed in full after eliminating preclinical studies and pape rs outside the scope of the *** adult traumatic brain injury,we review results from 14 papers detailing 227 subjects where evidence suggests donepezil is well tole rated and shows both objective and patient-reported efficacy for reducing cognitive *** children,3 pape rs report on 5 children recovering from traumatic brain injury,showing limited *** additional 15 pediatric studies conducted in populations at risk for cognitive dysfunction provide a broader look at safety and efficacy in 210 patients in the pediatric age *** its promise for efficacy in adults with traumatic brain injury and tole rability in pediatric patients,we believe further study of donepezil for children and adolescents with traumatic brain injury is warranted.

关键词： acetylcholinesterase inhibitor adult cognition donepezil pediatrics traumatic brain injury

解密稻田残留氮肥去向:作物吸收而非环境损失

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Science Bulletin 2024年第9期69卷 1212-1216页

作者：赵旭王盈盈蔡思源 jagdish k.Ladha Michael j.Castellano 夏龙龙谢迎新熊正琴谷保静邢光熹颜晓元 State key Laboratory of Soil and Sustainable Agriculture Changshu National Agro-Ecosystem Observation and Research StationInstitute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Nanjing 211135China University of Chinese Academy of Sciences Beijing 100049China Department of Plant Sciences University of CaliforniaDavis CA 95616USA Department of Agronomy Iowa State UniversityAmes IA 50011USA National Engineering Research Center for Wheat State Key Laboratory of Wheat and Maize Crop ScienceHenan Agricultural UniversityZhengzhou 450046China jiangsu key Laboratory of Low Carbon Agriculture and GHGs Mitigation College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China

Rice-based cropping systems are prevalent in Asia,accounting for 16%of global nitrogen(N)fertilizer consumption and providing billions of calories[1].Among these,the rice-wheat cropping system(RWCS)stands out as a critical contributor to global food security,covering an extensive area of 23.5 million hectares(mha)in Asia and sustaining 4.4 billion people[2].

关键词： cropping 环境损失 fertilizer

Supposition of graphene stacks to estimate the contact resistance and conductivity of nanocomposites

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 663-676页

作者： Y.ZARE M.T.MUNIR G.j.WENG k.Y.RHEE Biomaterials and Tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait Department of Mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of Mechanical Engineering(Bk21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study,the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity of samples are evaluated with developed equations superior to those previously *** contact resistance and nanocomposite conductivity are modeled by several influencing factors,including stack properties,interphase depth,tunneling size,and contact *** developed model's accuracy is verified through numerous experimental *** further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity are ***,the contact resistance is primarily dependent on the polymer tunnel resistivity,contact area,and tunneling *** dimensions of the graphene nanosheets significantly influence the conductivity,which ranges from 0 S/m to90 S/*** increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's ***,the thicker interphase and smaller tunneling size can lead to higher sample conductivity due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene polymer composite stacked nanosheet tunneling conductivity contact resistance interphase