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Numerical investigation of the convex effect on the behavior of crossing excavations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第10期12卷 747-757页

作者： min ZHANG Xing-hua WANG guang-cheng yang You WANG School of Civil Engineering Central South University Changsha 410075 China

A 3D numerical model considering the soil-structure interaction is presented in this paper to examine the ground movement and internal force during the construction of Qingdao North Metro Station, China with a special focus on the convex effect of the crossing excavation. The influence of intersection angles and soil resilience characteristics on deformation behavior is discussed, and the suitability of two alternative constitutive models applied in excavation simulation is also considered. The analysis results show that a notable convex effect appears to be associated with the crossing excavation, and the intersection is the key area requiring special attention. The displacements at the comer decrease with increasing crossing angles. The axial loads of struts along the retaining pile wall are unequal, and the values near the cross section are generally larger than the average loads of the left-sided ones. The modified Cam-Clay （MCC） model, which is capable of describing the loading-unloading criterion and identifying the stiffness difference of strain hardening between loading and unloading, can yield a relatively high accuracy of estimation for the behavior of excavations in comparison to the Mohr-Coulomb （MC） model. Furthermore, slight soil deformation resilience after unloading can reduce the ground surface settlement and enhance the ground stability.

关键词： Crossing excavation Convex effect Constitutive model Numerical simulation

Comparison of Ethylation at External Surface and Internal Cavity of H-MCM-22 Zeolite from Theoretical Calculations

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Chinese Journal of Chemistry 2020年第1期38卷 50-56页

作者： Yu-Jue Du Chuan-ming Wang guang yang Wei-min yang State Key Laboratory of Green Chemical Engineering and Industrial Catalysis SinopecShanghai Research Institute of Petrochemical TechnologyShanghai 201208China

Summaryof main observation and conclusion Understanding and optimizing structure of active sites is of significance in zeolite *** ethylation is an industrially important process catalyzed by H-MCM-22 zeolite;while the active sites still remain *** this work,density functional theory(DFT)calculations were employed to investigate the benzene ethylation at two different types of Br?nsted acid sites(BAS)in H-MCM-22 zeolite,namely the internal cavity(IC)acid site and the external surface(ES)acid *** the stepwise and concerted pathways were *** compari-son of the calculated energetics of two pathways indicates that the benzene ethylation reaction primarily proceeds via the concerted pathway at both the IC and ES acid sites of *** calculated overall Gibbs free energies at reaction condition(473 K and 3.5 MPa)on the IC and ES acid sites are 90 and 86 kJ/mol,with the rate constants of 1.20×10^3and 2.92×10^3s^-1,*** indicates that benzene ethylation could occur both on the IC and ES acid sites,with the catalytic activity of IC acid site being slightly lower than that of ES acid ***,we theoretically reveal that the acid strength at the ES site is slightly weaker than that at the IC site via the frequency shift after the adsorption of *** differences in dispersion interaction between ES and IC sites are also quantified by the adsorption of base molecules with different *** calculated results in this work demonstrate that the acid sites at the external surface of H-MCM-22 zeolites are suitable for benzene ethylation to produce ethylbenzene,providing theoretical implications for tailoring the distribution of active sites in H-MCM-22 zeolite.

关键词： zeolite benzene slightly

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence of CKD in Chinese adults

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Frontiers of Medicine 2024年第2期18卷 303-314页

作者： Yi Ding Xiaoli Xu Zhuojun Xin Qiuyu Cao Jiaojiao Huang Xianglin Wu Yanan Huo Qin Wan Yingfen Qin Ruying Hu Lixin Shi Qing Su Xuefeng Yu Li Yan Guijun Qin Xulei Tang Gang Chen min Xu Tiange Wang Zhiyun Zhao Zhengnan Gao Guixia Wang Feixia Shen Zuojie Luo Li Chen Qiang Li Zhen Ye Yinfei Zhang Chao Liu Youmin Wang Tao yang Huacong Deng Lulu Chen Tianshu Zeng Jiajun Zhao Yiming Mu Shengli Wu Yuhong Chen Jieli Lu Weiqing Wang guang Ning Yu Xu Yufang Bi Mian Li Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai National Clinical Research Center for Metabolic Diseases Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of ChinaShanghai Key Laboratory for Endocrine TumorState Key Laboratory of Medical GenomicsRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Jiangxi Provincial People’s Hospital Affiliated to Nanchang UniversityNanchang330000China Department of Endocrinology The Affiliated Hospital of Southwest Medical UniversityLuzhou646000China Department of Endocrinology The First Affiliated Hospital of Guangxi Medical UniversityNanning530000China Zhejiang Provincial Center for Disease Control and Prevention Hangzhou310000China Department of Endocrinology Affiliated Hospital of Guiyang Medical UniversityGuiyang550000China Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai200000China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430000China Sun Yat-sen Memorial Hospital Sun Yat-sen UniversityGuangzhou510000China Department of Endocrinology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450000China Department of Endocrinology The First Hospital of Lanzhou UniversityLanzhou730000China Fujian Provincial Hospital Fujian Medical UniversityFuzhou350000China Dalian Municipal Central Hospital Affiliated of Dalian Medical UniversityDalian116000China Department of Endocrinology The First Hospital of Jilin UniversityChangchun130000China Department of Endocrinology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou325000China Qilu Hospital of Shandong University Jinan250000China Department of Endocrinology The Second Affiliated Hospital of Harbin Medical UniversityHarbin150000China Department of Endocrinology Cen

Studies have found a U-shaped relationship between sleep duration and chronic kidney disease(CKD)risk,but limited research evaluated the association of reallocating excessive sleep to other behavior with *** included 104538 participants from the nationwide cohort of the Risk Evaluation of Cancers in Chinese Diabetic Individuals:A Longitudinal Study,with self-reported time of daily-life *** isotemporal substitution models,we found that substituting 1 h of sleeping with sitting,walking,or moderate-to-vigorous physical activity was associated with a lower CKD ***-time physical activity displacement was associated with a greater prevalence reduction than occupational physical activity in working *** stratified analysis,a lower CKD prevalence related to substitution toward physical activity was found in long *** pronounced correlations were observed in long sleepers with diabetes than in those with prediabetes,and they benefited from other behavior substitutions toward a more active *** U-shaped association between sleep duration and CKD prevalence implied the potential effects of insufficient and excessive sleep on the kidneys,in which the pernicious link with oversleep could be reversed by time reallocation to physical *** divergence in the predicted effect on CKD following time reallocation to behavior of different domains and intensities and in subpopulations with diverse metabolic statuses underlined the importance of optimizing sleeping patterns and adjusting integral behavioral composition.

关键词： sleep physical activity chronic kidney disease isotemporal substitution behavioral pattern

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灯泡贯流泵中不同射流参量的减阻特性研究

中国农村水利水电 2024年第10期 112-118,126页

作者：张杨杨刘德民陈旭光张凤鹏程宦中国海洋大学工程学院山东青岛266404 东方电机有限公司研究试验中心四川德阳618000

为探究灯泡贯流泵中不同射流参量的减阻特性,针对鲨鱼鳃部开展仿生设计,建立灯泡体前端设有射流端口的灯泡贯流泵模型,通过CFX研究射流端口安放位置、射流速度以及安放数量对灯泡贯流泵流场的影响机制。结果表明:近壁主流同射流相互碰撞... 详细信息

为探究灯泡贯流泵中不同射流参量的减阻特性,针对鲨鱼鳃部开展仿生设计,建立灯泡体前端设有射流端口的灯泡贯流泵模型,通过CFX研究射流端口安放位置、射流速度以及安放数量对灯泡贯流泵流场的影响机制。结果表明:近壁主流同射流相互碰撞,主流向射流传递轴向动量削弱近壁主流轴向速度;射流向主流传递径向动量增大近壁主流径向速度,托举近壁高流速带远离灯泡体,使近壁中低流速带拓宽、高流速带收缩,减小壁面切应力;计算预测减阻效果最高达23.069%,扬程提高0.083 m、效率提升1.729%,可为灯泡贯流泵优化设计、高效运行提供指导。

关键词：射流减阻灯泡贯流泵数值仿真

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Enhanced activation of peroxymonosulfate on layered molybdenum disulfide loaded with Co–La bimetallic oxide for efficient degradation of chloramphenicol

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Rare Metals 2024年第9期43卷 4628-4635页

作者： Yu-Ning Fan Yun-Qiu Zhang San-Shuang Gao Zeng-Hui Bi Yin Wang Shu-Xing Zhou Qian Liu Tian-Ping Lv guang-Zhi Hu Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan University Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and Science Institute for Advanced Study Chengdu University

The use of transition metal-activated peroxymonosulfate（PMS） as an advanced oxidation technology has gained recognition. This study developed a catalyst using cobaltDlanthanum bimetallic oxide supported on layered molybdenum disulfide （Mo S2） as a carrier. The CoDLa/Mo S2catalyst was synthesised through coprecipitation, followed by calcination with an optimised metal ratio of Co:La=2:1 to activate PMS and degrade trace chloramphenicol（CAP） in water. The chemical composition of the catalyst was confirmed using X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）. At catalyst and PMS dosages of 0.1 and 0.5 g·L-1, respectively, the degradation rate of CAP was 95% with in 30 min. The catalyst exhibitedstrong resistance to most interfering anions and maintained a high degradation rate at p H 3D11. Liquid chromatographyDmass spectrometry analysis revealed the potential degradation pathways of CAP in the CoDLa/Mo S2（2:1）/PMS system. For other pollutants, such as oxytetracycline,complete degradation was achieved within 20 min,demonstrating the broad applicability of the CoDLa/Mo S2（2:1）/PMS system for the degradation and removal of antibiotic organic contaminants. This study offers a feasible approach for the degradation of antibiotic organic pollutants, including CAP, in natural water bodies.

关键词： Catalysts

芳香烃受体在环境污染物损伤雄性哺乳动物生育力中的作用及分子机制

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生理学报 2024年第4期76卷 631-642页

作者：杨业斌彭真彭圣林梅光泉程一民宜春学院化学与生物工程学院江西省天然活性成分重点实验室宜春学院医学院宜春市人民医院宜春336000

近几十年全球男性精子质量持续下滑,而环境污染是其重要诱因。持久性有机污染物(persistent organic pollutants,POPs)由于具有高生物毒性、耐生物降解等特性而受到广泛关注。POPs中的多环芳烃及卤代芳烃类污染物主要通过激活芳香烃受体... 详细信息

近几十年全球男性精子质量持续下滑,而环境污染是其重要诱因。持久性有机污染物(persistent organic pollutants,POPs)由于具有高生物毒性、耐生物降解等特性而受到广泛关注。POPs中的多环芳烃及卤代芳烃类污染物主要通过激活芳香烃受体(aryl hydrocarbon receptor,AhR)损伤细胞生理功能,然而AhR在环境污染物损伤雄性哺乳动物生育力中的作用仍未被完全阐明。本文综述了多环芳烃型环境污染物苯并[a]芘、3-甲基胆蒽、7,12-二甲基苯并[a]蒽,卤代芳烃型环境污染物2,3,7,8-四氯二苯并对二恶英、多氯联苯、多溴二苯醚以及污染物复合体PM2.5、香烟烟雾冷凝液对雄性哺乳动物生殖功能的影响,并重点阐释了AhR在其中发挥的作用。本综述旨在揭示AhR在雄性哺乳动物生育力调控中所扮演的角色,以期为后续研究AhR与男性生殖功能的联系及临床特发性男性不育症发病机制提供线索。

关键词：芳香烃受体环境污染物芳香烃受体外源性配体雄性哺乳动物生育力分子机制

Atomic-scale characterization of multiple precipitating species in a precipitation-hardened martensitic stainless steel

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Journal of Iron and Steel Research International 2022年第2期29卷 207-214页

作者： Zhen-bao Liu Zhe yang Jian-xiong Liang Zhi-yong yang guang-min Sheng Division of Special Steels Central Iron and Steel Research Institute(CISRI)Beijing100081China School of Material Science and Engineering Chongqing UniversityChongqing400044China

Multiple precipitating species in a 2.2 GPa grade precipitation-hardened martensitic stainless steel with balanced ductility were characterized at atomic scale by atom probe *** results indicated that the clustering of solute atoms was promoted with progressive aging treatments.(Cr,Mo)-rich carbide(M_(2)C)precipitated at the linear dislocations in the as-aged *** segregation of Cr,Mo,and C at phase boundaries favored the precipitation of carbide and caused the formation of Cr-lean *** decomposition of martensitic matrix during aging led to the substantial precipitation of fine Cr-rich(α′Cr)*** with the first aging treated samples,a synergistic enhancement of both strength and ductility of the secondary aging treated(SAT)samples was primarily ascribed to the enhanced precipitation of Cr-rich ***,Ni-rich filmy reversed austenite precipitated at the lath boundary,which was beneficial to the ductility of SAT samples.

关键词： Aging treatment Nanoprecipitate Atom probe Spinodal decomposition Precipitation-hardened martensitic stainless steel

Synthesis of Ba-doped porous LaFeO_(3) microspheres with perovskite structure for rapid detection of ethanol gas

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Rare Metals 2021年第6期40卷 1651-1661页

作者： Pei Hao guang-min Qu Peng Song Zhong-Xi yang Qi Wang School of Material Science and Engineering University of JinanJinan 250022China Shandong Academy of Pharmaceutical Sciences Jinan 250101China

In this work,porous La_(1-x)Ba_(x)FeO_(3)(x=0.01,0.02,0.03,0.04 and 0.05) microspheres of the orthorhombic perovskite phase were prepared by an environment-friendly one-step hydrothermal method with a series of characterization of the six sensing *** results show that their grain size is between 21.2 and 23.2 nm,and the grain growth is inhibited with the increase in Ba-doping *** samples are all spherical with a diameter of about 10 μm,and the surface is very *** the gas sensing study of the samples,the results show that the La_(1-x)Ba_(x)FeO_(3) sensor exhibits a fairly high response to the ethanol *** particular,the La_(1-x)Ba_(x)FeO_(3) microspheres with a Ba-doping concentration of 2 mol% showed not only a significant improvement in sensitivity but also a rather rapid response recovery time compared to the undoped samples,demonstrating the superiority as an ethanol sensing *** importantly,the optimum operating temperature of La0.98Ba0.02FeO_(3) is only 200℃,while that of the pure LaFeO_(3) is 260℃.The Ba-doped porous microspheres prepared are a high-performance sensing material capable of rapid and accurate detection of ethanol.

关键词： Perovskite LaFeO_(3)microspheres Ba-doped Ethanol Gas sensors

A contradictory phenomenon of thicken pericardium and cardiac compression without inferior vena cava dilation:sign of IVC escape

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Journal of Geriatric Cardiology 2024年第5期21卷 583-587页

作者： Tie-Nan CHEN Shuang ZHAO Shuai QIAO Yong-Yong HAN Qing LIU Chang-Le LIU guang-Ping LI Tong LIU Hua-Ying FU Department of Cardiovascular Surgery Second Hospital of Tianjin Medical UniversityTianjinChina Department of Cardiology Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular DiseaseTianjin Institute of Cardi-ologyThe Second Hospital of Tianjin Medical UniversityTianjinChina Department of Oncology Second Hospital of Tianjin Medical UniversityTianjinPeople's Republic of China

A 77-year-old female presented with shortness of breath and tightness of chest was *** past medical history included hypertension and she has been taking nifedipine *** years before,she was diagnosed with pericardial effusion(Figure 1)and had pericardiocentesis *** physical examination,her blood pressure was 151/100 mm-Hg and her pulse rate was 91 beats/min.

关键词： admitted cardiac thick