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天津空客A330宽体机厂房焊接加固过程结构性能监测与分析

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天津大学学报（自然科学与工程技术版） 2024年第4期57卷 335-342页

作者：陈志华王昭刘红波陈宇杨向燚张晓光天津大学建筑工程学院天津300072 河北工程大学土木工程学院邯郸056038 天津天保建设发展有限公司天津300308 天津建工科技有限公司天津300499

大跨度钢桁架加固方法多采用焊接加固增大截面法.针对大跨度钢桁架屋盖整体结构的负载焊接加固,以天津空客A321(A330宽体机厂房)屋盖为例,采用4片角钢,分肢与原H型钢的翼缘、腹板分别焊接的加固方式,设计了合理的焊接加固方案与监测方案... 详细信息

大跨度钢桁架加固方法多采用焊接加固增大截面法.针对大跨度钢桁架屋盖整体结构的负载焊接加固,以天津空客A321(A330宽体机厂房)屋盖为例,采用4片角钢,分肢与原H型钢的翼缘、腹板分别焊接的加固方式,设计了合理的焊接加固方案与监测方案,对结构关键构件在焊接加固过程中的应力、应变进行监测.以监测数据为依据,研究分析焊接加固过程中型钢与加固角钢的应力响应规律,验证钢桁架梁采用角钢焊接加固的传力有效性,判断焊接热输入的影响范围.结果表明:在负载焊接加固的过程中,局部高温热影响区引起应力重分布,加固角钢的存在对原有型钢构件起到了相应的承担作用,焊接加固过程中结构的安全性可以得到保证.此外,焊接加固时,通过监测相邻杆件的应力和应变,分析表明焊接热影响的范围在两个节间范围内,且带来的应力响应较小.

关键词：钢桁架梁负载状态焊接加固现场监测

基于三角芳香配体的金属有机框架对染料木素的吸附性能与机理

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食品与机械 2024年第3期40卷 18-25页

作者：杨湘怡程云辉姚丽许宙邢克宇长沙理工大学食品与生物工程学院湖南长沙410114 齐鲁工业大学〔山东省科学院〕食品科学与工程学院山东济南250353

目的:提高染料木素的吸附率。方法:采用水热法合成2种含不同尺寸三角芳香配体的MOFs(MOF-808和PCN-777),通过系列表征确定MOFs的合成,比较其与线性二元羧酸配体构筑的MOF(UiO-66)对染料木素的吸附效果;考察孔隙特征、疏水性变化等对吸... 详细信息

目的:提高染料木素的吸附率。方法:采用水热法合成2种含不同尺寸三角芳香配体的MOFs(MOF-808和PCN-777),通过系列表征确定MOFs的合成,比较其与线性二元羧酸配体构筑的MOF(UiO-66)对染料木素的吸附效果;考察孔隙特征、疏水性变化等对吸附性能的影响,利用X射线光电子能谱探究其吸附机理。结果:与线性配体构筑的UiO-66相比,三角芳香配体构筑的MOFs(MOF-808和PCN-777)的孔径分别从0.65 nm增大到1.81,3.55 nm,水接触角分别从47.91°增大到110.68°,128.23°。线性配体构筑的UiO-66对染料木素的吸附量为40.08 mg/g,吸附率为39.98%;而三角芳香配体构筑的MOFs(MOF-808和PCN-777)对染料木素的吸附量分别为61.80,81.75 mg/g,吸附率分别为61.63%,81.52%。结论:金属有机框架可用于染料木素的吸附富集,相较于线性配体,引入不同尺寸的三角芳香配体改变了MOFs孔径及疏水性,加强了MOFs的内部可及性并提供了更多吸附位点,从而提高了对染料木素的吸附效果。PCN-777对染料木素的吸附机理为金属螯合作用、π-π相互作用和疏水相互作用的协同。

关键词：锆基金属有机框架染料木素三角芳香配体孔径协同吸附机理

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枯草杆菌二联活菌颗粒联合乌司他丁治疗急性胰腺炎的效果及对氧化应激水平的影响

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首都食品与医药 2024年第4期31卷 60-62页

作者：杨向意刘麒富彭代娇江西省赣州市人民医院江西赣州341000 江西省赣州市蓉江新区人民医院江西赣州341000

目的探究枯草杆菌二联活菌颗粒联合乌司他丁(UTI)治疗急性胰腺炎(AP)的效果及对氧化应激水平的影响.方法共纳入赣州市人民医院收治的90例AP患者,选取时间为2020年12月-2023年8月,以随机数字表法分为两组,即对照组(n=45)、观察组(n=45)... 详细信息

目的探究枯草杆菌二联活菌颗粒联合乌司他丁(UTI)治疗急性胰腺炎(AP)的效果及对氧化应激水平的影响.方法共纳入赣州市人民医院收治的90例AP患者,选取时间为2020年12月-2023年8月,以随机数字表法分为两组,即对照组(n=45)、观察组(n=45),对照组接受UTI治疗,观察组接受UTI联合枯草杆菌二联活菌颗粒治疗,两组均治疗7d,比较两组治疗效果、主要症状缓解时间;于治疗前、后,比较两组氧化应激指标[超氧化物歧化酶(SOD)、丙二醛(MDA)]、肠黏膜功能指标[D-乳酸、二胺氧化酶(DAO)];并记录不良反应发生情况.结果与对照组比较,观察组总有效率更高,主要症状缓解时间(腹痛减轻、排气恢复等)更短,均有统计学差异(P0.05).结论枯草杆菌二联活菌颗粒联合UTI治疗AP可提高治疗效果,减轻氧化应激程度,改善肠黏膜功能,缓解患者症状.

关键词：急性胰腺炎乌司他丁枯草杆菌二联活菌颗粒氧化应激

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C_(6)F_(5))_(3)/chiral phosphoric acid

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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen Liu Zhi-Yuan Ren Chen yang xiangyi Shao Li Chen Xin Li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Magnitude and direction of temperature variability affect hospitalization for myocardial infarction and stroke:population-based evidence from Guangzhou,China

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 1-11页

作者： Zhou yang Murui Zheng Ze-Lin Yan Hui Liu xiangyi Liu Jie-Qi Jin Jiagang Wu Chun-Quan Ou State Key Laboratory of Organ Failure Research Department of BiostatisticsGuangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public HealthSouthern Medical UniversityGuangzhou 510515China Guangzhou Center for Disease Control and Prevention Guangzhou 510440China

Relationships between nonoptimal temperatures and cardiovascular disease(CVD)mortality have been well ***,evidence of the association between temperature variability(TV)and CVD morbidity is *** study aimed to quantify the risk and burden of CVD-related hospitalization associated with the magnitude and direction of *** on meteorology and population-based hospitalizations for myocardial infarction(MI)and stroke were collected in Guangzhou,China,from 2013 to *** temperature variability(HTV)was measured as the standard deviation of hourly temperature records over specific exposure *** direction(upward or downward)of HTV was defined as the average daily mean temperature change relative to that of the previous day during the exposure ***-Poisson regression was applied to assess the impact of HTV after adjusting for the daily mean temperature,and the hospitalization fractions attributable to HTV were calculated.A 1℃-increase in HTV was significantly associated with a 2.24%and 1.72%increase in hospitalizations for MI and hemorrhagic stroke(HS)at lag 0–1 d,respectively,and a 1.55%increase in hospitalizations for ischemic stroke(IS)at lag 0–3 *** the study period,5.99%,4.64%,and 4.53%of MI,HS,and IS hospitalizations,respectively,were attributable to *** upward TV exerts acute effects on CVD hospital admissions,whereas the impact of downward TV generally *** findings highlight the importance of the magnitude and direction of temperature fluctuations,in addition to the mean level,in assessing the adverse health impacts of temperature variations.

关键词： Hourly temperature variability Cardiovascular Hospitalization Direction China

Why H7N9 bird flu may cause scare in China？

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Chinese Medical Journal 2014年第1期127卷 193-195页

作者： Kong xiangyi Liu yang Guan Jian yang Yi Wang Renzhi Department of Neurosurgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences. Beijing 100730China

The first identified case of human infection with a novel influenza A （H7N9） virus occurred in eastern China during February and March,*** to the Center for Disease Control and Prevention （CDC）,Chinese mainland has recorded a total of 134 laboratory-confirmed cases of H7N9,among whom 45 died by *** has spread to eight provinces including Beijing and Shanghai in mainland and,on April 29,it was confirmed to have spread to Taiwan,1 and might be slowly gaining pace daily,about 31% have died,55% have recovered,and the rest are still sick and the fatality risk on admission to hospital was 36% （95% CI26%-45%） for H7N9.

关键词： INFLUENZA-A H7N9 VIRUS TRANSMISSION INFECTION RISK H5N1

Improving strength-ductility synchronously of Electron beam welded Ti600/Ti2AlNb joint through isothermal forging

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Progress in Natural Science:Materials International 2024年第3期34卷 532-539页

作者： Yongqiang Zhang xiangyi Xue Guoming Zheng Jingli Zhang Huiming Li Shewei Xin State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an Qin Ti Intelligent Manufacturing Technologies Co.Ltd. Northwest Institute for Nonferrous Metal Research Xi'an University of Science and Technology Avic Xi'an Aircraft Industry Group Company Ltd.

Different alloys can be flexibly combined to meet the performance needs of different parts of the compressor disc by welding process. However, achieving a good combination of dissimilar alloys with different mechanical properties has always been a research difficulty. In this work, a Ti600/Ti2AlNb joint was fabricated through electron beam welding and an isothermal forging was used to optimized its microstructure and mechanical performance. The isothermal forging process increases the ultimate tensile strength（UST） and yield strength（YS）of the Ti600/Ti2AlNb joint by ～18 %, while ～2.5 times the ductility. It is indicated that before forging, the Ti600/Ti2AlNb joint exhibits a much lower strength than that of Ti600 matrix, whereas the opposite is true after isothermal forging. The isothermal forging broken the coarse columnar grains of Ti600/Ti2AlNb joint and render to an equiaxed B2 structure in which the acicular α2and O phase are precipitated, resulting a synchronous enhancement of strength and ductility. This work may pave an effective routine for improving the comprehensive mechanical properties of dissimilar metal welding joint.

关键词： Electron beam welding Isothermal forging Mechanical performance Ti600/Ti2AlNb joint

愈痫灵方对戊四氮致痫大鼠Pannexin1炎症信号通路蛋白及炎症因子表达的影响

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现代中西医结合杂志 2024年第6期33卷 757-761,777页

作者：李广丽李振光李智雄王净净田明琴陈琼琼李浩月杨湘怡湖南中医药大学湖南长沙410036 湖南省脑科医院(湖南省第二人民医院) 湖南长沙410021

目的探讨愈痫灵方对戊四氮致痫大鼠Pannexin1(PANX1)炎症信号通路及炎症因子表达的影响。方法取健康雄性SD大鼠80只,随机选择10只作为对照组,腹腔注射生理盐水;其余70只腹腔注射戊四氮建立癫痫模型。将造模成功的40只大鼠随机分为模型... 详细信息

目的探讨愈痫灵方对戊四氮致痫大鼠Pannexin1(PANX1)炎症信号通路及炎症因子表达的影响。方法取健康雄性SD大鼠80只,随机选择10只作为对照组,腹腔注射生理盐水;其余70只腹腔注射戊四氮建立癫痫模型。将造模成功的40只大鼠随机分为模型组、愈痫灵方组、丙磺舒组和丙戊酸钠组,每组10只。愈痫灵方组给予3.24 g/(kg·d)愈痫灵方灌胃,丙磺舒组给予13.3 mg/(kg·d)丙磺舒灌胃,丙戊酸钠组给予31.9 mg/(kg·d)丙戊酸钠灌胃,模型组和对照组给予同等体积蒸馏水灌胃,均1次/d,连续灌胃14 d。末次灌胃结束后取大鼠颞叶内侧海马,采用Western blot法检测海马组织中PANX1、白细胞介素-1β(IL-1β)、p65、磷酸化p65(p-p65)蛋白表达情况;取腹主动脉血,采用ELISA法检测血清IL-1β、白细胞介素-6(IL-6)、核因子κB(NF-κB)水平。结果模型组海马组织中PANX1、IL-1β、p65、p-p65蛋白相对表达量均明显高于对照组(P均0.05);愈痫灵方组及丙戊酸钠组海马组织中IL-1β、p65、p-p65蛋白相对表达量均明显低于模型组和丙磺舒组(P均0.05);愈痫灵方组血清IL-6、NF-κB水平均明显高于丙戊酸钠组(P均0.05)。结论愈痫灵方可以降低癫痫大鼠海马组织中PANX1炎症信号通路蛋白的表达,减少下游炎症因子IL-1β、p65、p-p65的产生,这可能是其抗癫痫的作用机制之一。

关键词：癫痫愈痫灵方 Pannexin1 炎症因子戊四氮大鼠

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The role of proteasomes in tumorigenesis

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Genes & Diseases 2024年第4期11卷 155-169页

作者： xiangyi Zhou Ruqing Xu Yue Wu Li Zhou Tingxiu Xiang Department of Oncology The First Affliated Hospital of Chongqing Medical UniversityChongqing 400016China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China

Protein homeostasis is the basis of normal life activities,and the proteasomefamily plays an extremely important function in this *** proteasome 2os is a concentric circle structure with twoαrings and twoβrings *** proteasome 2os can perform both ATP-dependent and non-ATP-dependent ubiquitination proteasome degradation by binding to various subunits(such as 19S,11S,and 200 PA),which is performed by its active subunitβ1,β2,andβ*** proteasome can degrade misfolded,excess proteins tomaintain *** the same time,it can be utilized by tumors to degrade over-proliferate and unwanted proteins to support their *** can affect the development of tumors from several aspects including tumor signaling pathways such as NF-kB and p53,cell cycle,immune regulation,and drug ***-encoding genes have been found to be overexpressed in a variety of tumors,providing a potential novel target for cancer *** addition,proteasome inhibitors such as bortezomib,carfilzomib,and ixazomib have been put into clinical application as the first-line treatment of multiple *** and more studies have shown that it also has different therapeutic effects in other tumors such as hepatocellular carcinoma,non-small cell lung cancer,glioblastoma,and ***,proteasome inhibitors are not much effective due to their tolerance and singleness in other ***,further studies on their mechanisms of action and drug interactions are needed to investigate their therapeutic potential.

关键词： Bortezomib Cancer therapy Immunoproteasome Multiplemyeloma Proteasome 20S Proteasome inhibitor Thymoproteasom