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Effect of strata restraint on seismic performance of prefabricated sidewall joints in fabricated subway stations

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Frontiers of Structural and Civil Engineering 2023年第5期17卷 763-779页

作者： hua-Fei HE Zhao-Ping LI shao-Lin MA xiang-Yang CUI School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China

A disadvantage of the conventional quasi-static test method is that it does not consider the soil restraint effect.A new method to test the seismic performance of prefabricated specimens for underground assembled structures is proposed,which can realistically reflect the strata restraint effect on the underground *** work combined with finite element(FE)analysis is performed in this *** full-scale sidewall specimens with different joint forms are designed and *** related to the seismic performance and damage modes are analyzed comprehensively to reveal the mechanism of the strata restraint effect on the prefabricated sidewall *** results show that the strata restraint effect effectively improves the energy dissipation capacity,load-bearing capacity,and the recoverability of the internal deformation of the precast sidewall ***,the strata restraint effect reduces the ductility of the precast sidewall components and aggravates the shear and bending deformations in the core region of the connection ***,the strata restraint effect significantly affects the seismic performance and damage mode of the prefabricated sidewall *** FE model that can be used to conduct a seismic performance study of prefabricated specimens for underground assembled structures is proposed,and its feasibility is verified via comparison with test data.

关键词： underground structures precast sidewall specimen seismic test method bearing capacity energy dissipation capacity plastic deformation

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电子工业挥发性有机物排放及健康风险评价

中国环境科学 2025年第2期45卷 1074-1087页

作者：吕喆李国昊白画画刘晓宇邵霞聂磊北京市生态环境保护科学研究院国家城市环境污染控制工程技术研究中心城市大气挥发性有机物污染防治技术与应用北京市重点实验室北京100037

为研究电子工业挥发性有机物(VOCs)排放特征及其健康风险影响,选取10家典型的电子企业,对其生产过程中产生的工艺废气进行样品采集和VOCs检测,并通过美国EPA和ACGIH方法评估其对人体健康的影响.结果表明:不同电子企业排气筒VOCs排放存... 详细信息

为研究电子工业挥发性有机物(VOCs)排放特征及其健康风险影响,选取10家典型的电子企业,对其生产过程中产生的工艺废气进行样品采集和VOCs检测,并通过美国EPA和ACGIH方法评估其对人体健康的影响.结果表明:不同电子企业排气筒VOCs排放存在差异,半导体器件与电子终端产品行业VOCs浓度相对高于显示器及光电子器件与印制电路板行业,其VOCs浓度分别为13.41~13.63,3.34~86.11,7.86~9.75和4.31~4.67mg/m^(3);半导体器件排气筒废气中VOCs以烷烃为主(70.56%~70.78%),质量分数最高的VOCs物种为二甲基戊烷(32.03%~33.60%);显示器及光电子器件和印制电路板企业排气筒废气中VOCs均以OVOCs为主,质量分数分别为(93.48%~95.87%)和(92.27%~93.05%),且质量分数最高的分别为丙酮(91.89%~94.99%)和异丙醇(80.36%~83.07%);电子终端产品行业由于生产产品不同,导致排气筒废气中VOCs组分存在差异,但以OVOCs、芳香烃和烷烃为主;不同企业间分歧系数为0.67~0.91,即VOCs源成分谱必不相似;半导体器件的非致癌风险HR最高(484.35),其次为显示器及光电子器件(447.46)、电子终端产品(11.74~87.35)和印制电路板(2.25),即各电子行业长期暴露均会造成非致癌健康危害;半导体器件(1.63×10^(-3))、电子终端产品(1.64×10^(-4)~5.16×10^(-3))行业LCR值较高,会产生确定的致癌风险;显示器及光电子器件、印制电路板行业LCR值分别为1.74×10^(-5)和1.40×10^(-5),有大概率致癌风险;电子终端产品子行业的总Ei值相对较大,显示器及光电子器件行业的总Ei值最小,但所有电子行业的Ei值均低于0.1,表明电子行业VOCs排放可能不会对工人产生健康影响.EPA和ACGIH方法评估致癌风险的结果差异较大,主要是因为两种方法对VOCs物种暴露参考浓度的限定指标不同.但整体来看,电子终端企业产品及半导体器件行业排放的VOCs健康风险远高于其他两个子行业,因此,应重点加强两个行业VOCs管控以保护工人健康.

关键词：电子工业挥发性有机物(VOCs) 排放特征健康影响

探讨神经内科病患压疮危险因素与相应护理预防措施

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泰山医学院学报 2017年第6期38卷 646-648页

作者：张晓娟胥婷王少华付春香济宁医学院附属医院山东济宁272000 泰山医学院附属医院山东泰安271000

目的探讨神经内科病患压疮危险因素与相应护理预防措施。方法采用回顾分析法选取2013年1月—2016年10月我院收治的神经内科住院病患208例随机分为观察组与对照组各104例,对照组实施常规压疮护理,观察组采用科室自制压疮危险因素评估量... 详细信息

目的探讨神经内科病患压疮危险因素与相应护理预防措施。方法采用回顾分析法选取2013年1月—2016年10月我院收治的神经内科住院病患208例随机分为观察组与对照组各104例,对照组实施常规压疮护理,观察组采用科室自制压疮危险因素评估量表对病患实施评估,并实施相应护理预防措施,对比两组病患住院期间压疮发生情况。结果 208例病患共发生压疮18例,压疮均为I度,其中观察组发生压疮5例,压疮发生率为4.8%,对照组发生压疮13例,压疮发生率为12.5%,对照组病患压疮发生率明显高于观察组,差异均具有统计学意义(P<0.05)。结论意识障碍、活动能力、移动能力是导致神经内科病患压疮三大危险因素,对病患发生压疮的危险性因素进行预测评估并采用针对性的预防与有效护理措施能够有效降低压疮发生率,值得临床推广使用。

关键词：神经内科压疮危险因素护理预防措施

Evaluating risk factors for surgical site infections and the effectiveness of prophylactic antibiotics in patients undergoing laparoscopic cholecystectomy

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World Journal of Gastrointestinal Surgery 2025年第1期17卷 125-131页

作者： shao-hua Wang Department of General Surgery Guangdong Hydropower HospitalGuangzhou 511356Guangdong ProvinceChina

BACKGROUND Surgical site infections(SSIs)are a significant complication in laparoscopic cholecystectomy(LC),affecting patient outcomes and healthcare *** To identify risk factors associated with SSIs and evaluate the effectiveness of prophylactic antibiotics in reducing these *** A comprehensive retrospective evaluation was conducted on 400 patients who underwent LC from January 2022 to January *** were divided into infected(n=36)and non-infected(n=364)groups based on the occurrence of *** collected included age,diabetes mellitus status,use of prophylactic antibiotics,and specific surgical *** analyses using SPSS(Version 27.0)involved univariate and multivariate logistic regression to determine factors influencing the risk of *** The use of prophylactic antibiotics significantly reduced the incidence of SSIs(χ²=68.34,P<0.01).Older age(≥60 years)and comorbidities such as diabetes mellitus were identified as significant risk *** complications like insufficient cystic duct stump,gallbladder perforation,and empyema also increased SSI ***,factors such as intraoperative blood loss and operation time did not significantly impact SSI *** Prophylactic antibiotics are effective in reducing the risk of SSIs in patients undergoing ***,diabetes mellitus,and certain surgical complications significantly contribute to the *** management of these risk factors is essential to improve surgical outcomes and reduce the incidence of SSIs.

关键词： Surgical site infections Laparoscopic cholecystectomy Prophylactic antibiotics Risk factors Surgical outcomes

Simulation of solute transportation within porous particles during the bioleaching process

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 389-396页

作者： Sheng-hua Yin Ai-xiang Wu shao-yong Wang Hong-jiang Wang School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China School of Mechanical Engineering University of Western Australia Perth 6009 Australia

A mathematical model, accounting for the sulfuric acid and ferric ions diffusion and the copper sulfide mineral leaching process, was developed for an ore particle by considering its porous structure. It was simulated with the simulation tool COMSOL Multiphysics. The simulation results show that the highest acid and ferric concentrations near the particle surface are apparent, while the concentrations in the central particle increase slightly as the less-porous ore core with low permeability prevents the oxidation from penetrating. The extraction of the mineral near the particle surface is the maximum, mainly because of ample sulfuric acid, ferric ions, bacteria, and oxygen available for the leaching process. Because of low oxidation concentration in the central part of the particle, the reaction rate and copper sulphide conversion are small. The simulation shows good agreement with the experimental results.

关键词： simulation solute transportation bioleaching copper sulphide porous particle

New measurement of ^(63)Cu(γ,n)^(62)Cu cross-section using quasi-monoenergeticγ-ray beam

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Nuclear Science and Techniques 2025年第2期36卷 131-140页

作者： Zhi-Cai Li Zi-Rui Hao Qian-Kun Sun Yu-Long Shen Long-xiang Liu Hang-hua Xu Yue Zhang Pu Jiao Meng-Die Zhou Yu-Xuan Yang Sheng Jin Kai-Jie Chen Zhen-Wei Wang Shan Ye Xin-xiang Li Chun-Wang Ma Hong-Wei Wang Gong-Tao Fan Wen Luo School of Nuclear Science and Technology University of South ChinaHengyang 421001China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China School of Physics Henan Normal UniversityXinxiang 453007China China Institute of Atomic Energy Beijing 102413China Institute of Nuclear Science and Technology Henan Academy of SciencesZhengzhou 450046China

We present new data on the^(63)Cu(γ,n)cross-section studied using a quasi-monochromatic and energy-tunableγbeam produced at the Shanghai Laser Electron Gamma Source to resolve the long-standing discrepancy between existing measurements and evaluations of this *** an unfolding iteration method,^(63)Cu(γ,n)data were obtained with an uncertainty of less than 4%,and the inconsistencies between the available experimental data were ***γ-ray strength function of^(63)Cu(γ,n)was successfully extracted as an experimental *** further calculated the cross-section of the radiative neutron capture reaction^(62)Cu(n,γ)using the TALYS *** calculation method enables the extraction of(n,γ)cross-sections for unstable nuclides.

关键词： ^(63)Cu(γ n)reaction Cross-section data Quasi-monochromaticbeam Radiative neutron capture reaction

Effects of Organic Materials Applied to Saline Soil on Crop Growth and Soil Saline-alkali Index

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huanjing Kexue/Environmental Science 2025年第3期46卷 1751-1761页

作者： Yang, Xiao-Juan He, Hao Cheng, Li-Yang Chang, xiang-Jie Li, Shuai Yu, Meng-Meng Wang, Bin-Quan Li, Jun-hua Key Laboratory of Oasis Eco-Agriculture Department of Resources and Environmental Sciences College of Agronomy Shihezi University Shihezi832003 China

To provide a theoretical basis for the scientific application of organic materials in salinized soil and the improvement of soil quality and to explore the response phenotype of an organic material-salinized soil-plant system，the salinized soil in Xinjiang was considered as the research object，and cotton，rape，and oil sunflower were considered as the test crops. Six treatments，including the control group，microbial agent，humic acid，organic fertilizer，biochar，and straw，were set up for indoor culture experiments. The effects of different organic materials on the growth of cotton，oil sunflower，and rape crops and soil saline-alkali indexes under moderate salinization soil conditions were analyzed，and the combinations with certain improvement effects were screened out. This provided a certain experimental basis for the application and promotion of organic materials in Xinjiang. The results showed that，compared with that under the control treatment，the application of the microbial inoculant，organic fertilizer，and biochar had a significant effect on crop growth. At 60 d of emergence，the dry weight of cotton after the application of the microbial inoculant，organic fertilizer，and biochar increased by 41%，43%，and 25%，respectively. The dry weight of oil sunflower increased by 5%，13%，and 27%，respectively. The dry weight of rape increased by 113%，104%，and 83%，respectively. After the application of organic fertilizer and biochar，the emergence rate of cotton and rape increased by 14.3% and 10.2%，respectively，and 26.50% and 20.82%，respectively. Taking the results of the soil salt-alkali index analysis at 60 d after seedling emergence as an example，the application of the microbial agent and straw had no significant effect on the total amount of water-soluble salt in the soil，whereas the application of humic acid，organic fertilizer，and biochar increased the total amount of water-soluble salt in the soil. The application of the microbial agent and straw could reduce soil pH，and the appl

关键词： Cotton

Evolution of Al2O3 inclusions by cerium treatment in low carbon high manganese steel

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Journal of Iron and Steel Research International 2017年第9期24卷 925-934页

作者： Hao Li Yan-chong Yu xiang Ren shao-hua Zhang She-bin Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024ShanxiChina

The influence of cerium（Ce）treatment on the morphologies,size and distributions of Al_2O_3 inclusions in low carbon high manganese steel was investigated by OM,SEM-EDS and theoretical *** results showed that Ce can modify the morphologies and types of Al_2O_3 *** Ce treatment,the irregular Al_2O_3 inclusions were replaced by smaller and dispersive spherical cerium *** effects of treatment time and Ce content on the evolution of Al_2O_3 inclusions were *** indicated that Al_2O_3 inclusions were wrapped by rare earth inclusions to form a ring like shape Ce-enriched band around the *** was established to elucidate the evolution mechanism of Al_2O_3 *** kinetics of inclusions was discussed qualitatively to analyze the velocity controlled *** was found that diffusion of Ce^（3＋）and Al^（3＋）in solid inclusion core and the formed intermediate layer would be the limited step during the evolution process.

关键词： Low carbon high manganese steel Inclusion Cerium treatment Evolution mechanism Transferring kinetics

Entanglement Dynamics of Two Qubits Coupled to a Noise Environment

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Communications in Theoretical Physics 2009年第4期51卷 637-640页

作者： LIU Jin xiang shao-hua CUI Hui-Ping LI Jian Department of Physics School of Science Beijing Institute of Technology Beijing 100081 China Department of Physics and electronic Information Science Huaihua University Huaihua 418008 China

We study the time evolution of two two-state systems （two qubits） initially in the pure entangled states or the maximally entangled mixed states interacting with the individual environmental noise. It is shown that due to environment noise, all quantum entangled states are very fragile and become a classical mixed state in a short-time limit. But the environment can affect entanglement in very different ways. The type of decoherence process for certain entangled states belongs to amplitude damping, while the others belong to dephasing decoherenee.

关键词： decoherence entanglement pure state mixed state