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强震动随机性对重力坝动水压力影响研究

水电能源科学 2024年第6期42卷 153-157页

作者：吴茂林何卫平刘聪宇曹绪文姚惠芹三峡大学水利与环境学院湖北宜昌443002 三峡大学湖北省水电工程施工与管理重点实验室湖北宜昌443002

针对现行水工抗震规范推荐的动水作用计算方法未考虑地震动随机性的问题,研究了强震动随机性对动水压力的影响。首先以Westergaard级数解为基础,探讨声固耦合法模拟动水压力的可行性;然后以选取的25条天然波和生成的25条人工波为基础,... 详细信息

针对现行水工抗震规范推荐的动水作用计算方法未考虑地震动随机性的问题,研究了强震动随机性对动水压力的影响。首先以Westergaard级数解为基础,探讨声固耦合法模拟动水压力的可行性;然后以选取的25条天然波和生成的25条人工波为基础,研究强震动随机性对重力坝动水压力分布规律和最大值的影响。结果显示,Westergaard级数解仅适用低频激振力,声固耦合法对不同频率的激振力均适用;在动水压力分布规律方面,刚性地基情况下与Westergaard附加质量法规律一致,弹性地基情况下与规范推荐的动水压力系数规律相似;在强震动随机性影响方面,人工波随机性带来的动水压力最大值对均值的偏离程度为16.1%~22.2%,天然波随机性带来动水压力最大值对均值的偏离程度为39.4%~49.8%,天然波随机性对动水压力的影响是人工波的2.0~2.5倍。

关键词：重力坝动水压力声固耦合强震动随机性 Westergaard方法

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Influence of order-disorder transition on the mechanical andthermophysical properties of ABOhigh-entropy ceramicsInfluence of order-disorder transition on the mechanical and thermophysical properties of A_(2)B_(2)O_(7)high-entropy ceramics 1

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Journal of Advanced Ceramics 2022年第8期11卷 1222-1234页

作者： Jiatong ZHU Mingyue wei jie XU Runwu YANG Xuanyu MENG Ping ZHANG Jinlong YANG Guangzhong LI Feng GAO State Key Laboratory of Solidification Processing MIIT Key Laboratory of Radiation Detection Materials and DevicesSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China NPU–QMUL Joint Research Institute of Advanced Materials and Structure Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Porous Metal Materials Northwest Institute for Nonferrous Metal ResearchXi’an 710016China

The order–disorder transition(ODT)of A_(2)B_(2)O_(7)compounds obtained enormous attention owing to the potential application for thermal barrier coating(TBC)*** this work,the influence of ODT on the mechanical and thermophysical properties of dual-phase A_(2)B_(2)O_(7)high-entropy ceramics was investigated by substituting Ce^(4+)and Hf^(4+)with different ionic radii on B-sites(Zr^(4+)).The X-ray diffraction(XRD),Raman,and transmission electron microscopy(TEM)results show that rA3+/rB^(4+)=1.47 is the critical value of ODT phase boundary with different doping B-site ion contents,and the energy dispersive spectroscopy(EDS)results further indicate the uniform distribution of ***,owing to the high intrinsic disorder derived from high-entropy effect,the A_(2)B_(2)O_(7)high-entropy ceramics exhibit unreduced modulus(E0≈230 GPa)and enhanced mechanical properties(HV≈10 GPa,KIC≈2.3 MPa·m^(0.5)).A_(2)B_(2)O_(7)high-entropy ceramics exhibit excellent thermal stability with relatively high thermal expansion coefficients(TECs)(Hf_(0.25),11.20×10-6 K-1,1000℃).Moreover,the matching calculation implied that the ODT further enhances the phonon scattering coefficient,leading to a relatively lower thermal conductivity of(La_(0.25)Eu_(0.25)Gd_(0.25)Yb_(0.25))2(Zr_(0.85)Ce_(0.15))_(2)O_(7)(1.48–1.51 W/(m·K),100–500℃)compared with other *** present work provides a novel composition design principle for high-entropy ceramics,as well as a material selection rule for high-temperature insulation applications.

关键词： high-entropy ceramics A_(2)B_(2)O_(7) order-disorder transition(ODT) mechanical properties thermal conductivity

南京地区局地积累型和外来输送型O_(3)污染模拟研究

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地球与环境 2024年第2期52卷 154-165页

作者：裴宇儇彭薇王红磊卢文赵天良刘思晗武自豪可玥南京信息工程大学气象灾害预报预警与评估协同创新中心中国气象局气溶胶-云-降水重点开放实验室湖南省气象信息中心气象防灾减灾湖南省重点实验室

利用观测资料和WRF-Chem空气质量模式对南京地区局地积累型和外来输送型O_(3)污染过程的时空分布特征和潜在机制进行了研究。结果表明:(1)水平分布特征,在两次O_(3)污染整体过程中,外来输送型O_(3)污染浓度高值区分布范围相比局地积累... 详细信息

利用观测资料和WRF-Chem空气质量模式对南京地区局地积累型和外来输送型O_(3)污染过程的时空分布特征和潜在机制进行了研究。结果表明:(1)水平分布特征,在两次O_(3)污染整体过程中,外来输送型O_(3)污染浓度高值区分布范围相比局地积累型更大且较为分散。但在两次O_(3)污染过程中最严重的白天,局地积累型O_(3)污染浓度高值区分布范围大且集中,O_(3)浓度大部分均超过160μg/m^(3);而外来输送型O_(3)污染浓度高值区分布范围更小且更为分散,O_(3)浓度在120~160μg/m^(3)的地区范围显著大于局地积累型O_(3)污染;(2)垂直分布特征,在污染过程前期,局地积累型O_(3)污染在2 km以下高度处有着高浓度O_(3),浓度最高超250μg/m^(3),而外来输送型O_(3)污染浓度高值区主要集中在2~2.5 km高度处,且高值区浓度最高不超过200μg/m^(3);在污染过程中期,局地积累型O_(3)污染浓度高值区集中在2 km高度下,且在1 km左右高度处O_(3)浓度出现最大值;而外来输送型O_(3)污染浓度高值区最高可达到2.6 km左右,并且浓度最大值集中在1.5 km高度以下,均超过250μg/m^(3);在污染过程后期,局地积累型O_(3)污染浓度高值区逐渐消散,但外来输送型O_(3)污染在0.5~3 km高度内仍出现大范围O_(3)浓度高值区;(3)在生成机理方面,近地面O_(3)的高浓度在局地积累型O_(3)污染中主要依赖于垂直混合,96h内总贡献为451.7μg/m^(3),在总过程量中占比为66.2%,而在外来输送型O_(3)污染中主要依赖于水平平流和垂直混合,72h内总贡献分别为1050.2μg/m^(3)和799.1μg/m^(3),总量在总过程量中占比为61.5%。在500 m高度处,局地积累型O_(3)污染前期O_(3)的高浓度主要依赖于垂直平流和化学过程,中期只依赖于化学过程,后期则主要依赖于水平平流和化学过程。但在外来输送型O_(3)污染前中后期中高O_(3)浓度均主要依赖于水平平流和化学过程。在1000 m高度处,两个过程中O_(3)浓度的正贡献均主要受化学过程控制。

关键词： O_(3) 观测分析 WRF-Chem 过程分析南京

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弗莱维赫杂交牛与荷斯坦牛抗病性基因分析

中国奶牛 2024年第6期 17-21页

作者：房文斌蔺文龙林为民李怡赵艳梅刘强新疆生产建设兵团第八师畜牧兽医工作站石河子832000

为揭示弗莱维赫(德系西门塔尔)与荷斯坦杂交牛(以下简称弗荷杂交牛)与荷斯坦牛在抗病力遗传的差异,利用Igenity® Select Profile (ISP)奶牛遗传评估项目,选取弗荷杂交牛与荷斯坦牛各100头,以临床常见的存活力、酮病、胎衣不下、产乳热... 详细信息

为揭示弗莱维赫(德系西门塔尔)与荷斯坦杂交牛(以下简称弗荷杂交牛)与荷斯坦牛在抗病力遗传的差异,利用Igenity® Select Profile (ISP)奶牛遗传评估项目,选取弗荷杂交牛与荷斯坦牛各100头,以临床常见的存活力、酮病、胎衣不下、产乳热、乳房炎、真胃移位、子宫炎、牛奶体细胞数等主要性状开展遗传评估检测。结果显示弗荷杂交牛在存活力、产乳热、真胃移位、乳房炎、胎衣不下抗性遗传评估值上显著优于荷斯坦牛,统计学差异极显著(P0.05),在生产寿命遗传评估值上显著低于荷斯坦牛,统计学差异极显著(P<0.01)。本研究从基因及遗传育种角度初步揭示弗荷杂交牛与荷斯坦牛在抗病性遗传方面的差异,为弗莱维赫牛改良奶牛实现乳肉牛融合发展提供参考。

关键词：弗莱维赫荷斯坦弗荷杂交牛奶牛遗传评估

Photobiomodulation provides neuroprotection through regulating mitochondrial fission imbalance in the subacute phase of spinal cord injury

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Neural Regeneration Research 2023年第9期18卷 2005-2010页

作者： Xin Li Xuan-Kang Wang Zhi-jie Zhu Zhuo-wen Liang Peng-Hui Li Yang-Guang Ma Tan Ding Kun Li Xiao-Shuang Zuo Cheng Ju Zhi-Hao Zhang Zhi-wen Song Hui-Lin Quan Jia-wei Zhang Liang Luo Zhe Wang Xue-Yu Hu Department of Orthopedics Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina 2967 Hospital of People’s Liberation Army Joint Logistic Support Force DalianLiaoning ProvinceChina

Increasing evidence indicates that mitochonarial lission imbalance plays an important role in derayed neuronal cell death. Our previous study round that photo biomodulation improved the motor function of rats with spinal cord ***,the precise mechanism remains *** investigate the effect of photo biomodulation on mitochondrial fission imbalance after spinal cord injury,in this study,we treated rat models of spinal co rd injury with 60-minute photo biomodulation(810 nm,150 mW) every day for 14 consecutive *** electron microscopy results confirmed the swollen and fragmented alte rations of mitochondrial morphology in neurons in acute(1 day) and subacute(7 and 14 days) *** biomodulation alleviated mitochondrial fission imbalance in spinal cord tissue in the subacute phase,reduced neuronal cell death,and improved rat posterior limb motor function in a time-dependent *** findings suggest that photobiomodulation targets neuronal mitochondria,alleviates mitochondrial fission imbalance-induced neuronal apoptosis,and thereby promotes the motor function recovery of rats with spinal cord injury.

关键词： low-level laser therapy mitochondria mitochondrial dynamics mitochondrial fission imbalance neuron photobiomodulation secondary injury spinal cord injury

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医院管理信息系统建设及分析

移动信息 2024年第1期46卷 76-79页

作者：魏杰郓城县双桥镇卫生院山东菏泽274706

在医院构建电子信息工程系统时,首先需要考虑各项需求,如医疗档案、系统安全性、互操作性、用户友好性等。电子信息工程系统在医院管理中的主要应用包括医疗数据的电子化统计、医疗档案的信息化管理、医务人员工作能力的智能化考核等。... 详细信息

在医院构建电子信息工程系统时,首先需要考虑各项需求,如医疗档案、系统安全性、互操作性、用户友好性等。电子信息工程系统在医院管理中的主要应用包括医疗数据的电子化统计、医疗档案的信息化管理、医务人员工作能力的智能化考核等。文中围绕智能门诊管理系统的构建与应用、医院药房智能管理系统的构建与应用、医务人员智能管理系统的构建与应用等展开分析,以供参考。

关键词：医院管理电子信息工程系统智能化系统门诊管理药房管理

秸秆深埋配施硫酸铝对西辽河平原地区苏打盐碱土水盐运移的影响

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中国土壤与肥料 2024年第1期 60-69页

作者：陈希杨树青温晓雨郭富强付娆马卫华刘红霞内蒙古农业大学内蒙古呼和浩特010018 内蒙古恒源水利工程有限公司内蒙古呼和浩特010010 内蒙古自治区农牧业生态与资源保护中心内蒙古呼和浩特010010

为探索秸秆深埋和硫酸铝改良剂配施交互作用对苏打盐碱地水盐运移的影响,在通辽市科尔沁左翼中旗开展覆膜滴灌下不同硫酸铝用量与秸秆深埋的田间试验,以甜菜为指示作物,常规处理为对照(CK),在有无秸秆深埋(A、B)的条件下分别设置4水平... 详细信息

为探索秸秆深埋和硫酸铝改良剂配施交互作用对苏打盐碱地水盐运移的影响,在通辽市科尔沁左翼中旗开展覆膜滴灌下不同硫酸铝用量与秸秆深埋的田间试验,以甜菜为指示作物,常规处理为对照(CK),在有无秸秆深埋(A、B)的条件下分别设置4水平硫酸铝添加量(30、60、90、120 g/m^(2)),揭示硫酸铝用量、秸秆深埋与土壤含水率、盐分的相关关系,提出覆膜滴灌及秸秆深埋下适宜的硫酸铝用量。结果显示,未添加秸秆处理中B3处理0~50 cm土体平均含水率最高(23.8%),比CK高8.2%,且平均含盐量最低(1.69 g/kg),比CK低12.6%;添加秸秆处理中A3处理0~50 cm土体平均含水率最高(26.6%),比B3处理高2.8%,平均含盐量也最低(1.57 g/kg),比B3处理低19%,且平均积盐率最低,比B3处理降低7.6%;A3处理在10~20和20~30 cm处土壤含水率均显著高于B3处理(P<0.05),在0~10和20~30 cm处土壤含盐量较B3处理显著降低(P<0.05);A3处理0~30 cm各土层均有脱盐趋势,达到显著水平(P<0.05),平均脱盐率11.5%;硫酸铝和秸秆深埋交互作用与土壤含水率呈极显著正相关(0.808),与土壤含盐量呈显著负相关(-0.564)。秸秆深埋和硫酸铝改良剂综合作用可有效降低土壤pH值0.53~0.94,缓解土壤碱化度20.5%~21.9%。覆膜滴灌及秸秆深埋下硫酸铝用量在72~104 g/m^(2)为适宜当地的推荐用量。研究结果可为西辽河平原地区盐碱土壤改良提供理论依据。

关键词：覆膜滴灌硫酸铝秸秆深埋苏打盐碱土水盐运移

Mechanism of progressive failure of a slope with a steep joint under the action of freezing and thawing:model test

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Journal of Mountain Science 2022年第10期19卷 2999-3012页

作者： LI Cong ZHANG Rong-tang ZHU jie-bing LU Bo SHEN Xiao-ke WANG Xiao-wei LIU jie-sheng WU Liang-liang ZHANG Xin-zhou School of Civil Engineering and Architecture Wuhan Polytechnic UniversityWuhan 430023China Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan 430010China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China

The stability of slope rock masses is influenced by freeze-thaw cycles in cold region,and the mechanism of stability deterioration is not *** order to understand the damage and progressive failure characteristics of rock masses under the action of freezing and thawing,a model test was conducted on slope with steep joint in this *** temperature,frost heaving pressure and deformation of slope rock mass were monitored in real-time during the test and the progressive failure mode was *** experimental results show that the temperature variations of cracking and the rock mass of a slope are *** are obvious latent heat stages in the temperature-change plot in the crack,but not in the slope rock *** frost heaving effect in the fracture is closely related to the constraint conditions,which change with the deformation of the *** frost heaving pressure fluctuates periodically during freezing and continues to decrease during *** surface deformation of the rock mass increases during freezing,and the deformation is restored when it ***-thaw cycling results in residual deformation of the rock mass which cannot be fully *** shows that the rock mass at the free side of the steep-dip joint rotates slightly under the frost heaving effect,causing fracture *** fracture propagation pattern is a circular arc at the beginning,then extends to the possible sliding direction of the rock *** heaving force and fracture water pressure are the key factors for the failure of the slope,which can cause the crack to penetrate the rock mass,and a landslide ensues when the overall anti-sliding resistance of the rock mass is overcome.

关键词： Rock slope Fractured rock mass Freeze-thaw cycle Model experiment Stability degradation mechanism Failure mode

An Efficient Message Dissemination Scheme for Minimizing DeliveryDelay in Delay Tolerant Networks

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Journal of Computer Science & Technology 2018年第6期33卷 1101-1124页

作者： En Wang wei-Shih Yang Yong-Jian Yang jie Wu wen-Bin Liu Department of Computer Science and Technology Jilin University Changchun 130012 China Department of Mathematics Temple University Philadelphia PA 19122 U.S.A. Department of Computer and Information Science Temple University Philadelphia PA 19122 U.S.A.

Delay tolerant networks （DTNs） are a kind of sparse and highly mobile wireless networks, where no stableconnectivity guarantee can be assumed. Most DTN users have several points of interest （PoIs）, and they enjoy disseminatingmessages to the other users of the same PoI through WiFi. In DTNs, some time-sensitive messages （disaster warnings, searchnotices, etc.） need to be rapidly propagated among specific users or areas. Therefore, finding a path from the source tothe destination with the shortest delay is the key problem. Taking the dissemination cost into consideration, we proposean efficient message dissemination strategy for minimizing delivery delay （MDMD） in DTNs, which first defines the user＇sactiveness according to the transiting habit among different PoIs. Furthermore, depending on the activeness, an optimaluser in each PoI is selected to constitute the path with the shortest delay. Finally, the MDMD with inactive state （on theway between PoIs） is further proposed to enhance the applicability. Simulation results show that, compared with otherdissemination strategies, MDMD achieves the lowest average delay, and the comparable average hopcounts, on the premisethat the delivery ratio is guaranteed to be 100% by the sufficient simulation time.

关键词： delay tolerant network (DTN) point of interest (PoI) dissemination strategy minimizing delay