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Transformation behavior of precipitates during artificial aging at 170℃in Al-Mg-Si-Cu alloys with and without Zn addition

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Rare Metals 2021年第7期40卷 1907-1914页

作者： Shang zhu zhi-Hui Li Li-Zhen Yan xi-Wu Li Shu-Hui Huang Hong-Wei Yan Yong-An Zhang bai-qing xiong State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co..LtdBeijing 101407China

The transformation behavior of precipitates in Al-Mg-Si-Cu alloys with and without Zn addition during artificial aging at 170℃was investigated in this *** Al-Mg-Si-Cu alloys with and without Zn addition,two types of precipitates,needle-likeβ″and lath-like L,are formed with the aging time increasing from 8 to 34 *** needle-likeβ″precipitate exhibits a Mg-to-Si atomic ratio of 1.31 which is in agreement with the theoretical ratio of1.25 forβ″(Mg5 Al2 Si4).In addition,theβ″precipitate is supposed to contain Al and *** further partitioning of Mg,Si and Cu and release of Al,the needle-likeβ″precipitate can transform to lath-like L *** L phase has significantly higher concentrations of Mg,Si and Cu and lower concentration of Al,with a higher Mg-to-Si atomic ratio(1.41)deviated from theoretical ratio ofβ″.However,the major of Zn has a random distribution in Al matrix and exhibits no significant partitioning into *** remained in matrix can enhance the transformation ofβ″precipitates to L precipitates.

关键词： Al-Mg-Si-Cu alloys Zn addition Precipitates Transformation

Impact of Traffic Emissions on Local Air Quality and the Potential Toxicity of Traffic-related Particulates in Beijing, China

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Biomedical and Environmental Sciences 2012年第6期25卷 663-671页

作者： TIAN Lei ZHANg Wei LIN zhi qing ZHANg Hua Shan xi zhu ge CHEN Jian Hua WANg Wei Laboratory for Environmental and Food Safety Risk Monitoring Technology Institute of Health and EnvironmentalMedicine Tianjin 300050 China Chinese Academy of Environmental Sciences Beijing 100012 China

Objective Air-borne particulates from different sources could have different physicochemical properties and inflammatory potentials. This study aims to characterize the chemical compositions and the toxicity of ambient particulate matter （PM） associated with traffic emissions. Methods The concentrations of trace elements, organic carbon （OC）, elemental carbon （EC） and polycyclic aromatic hydrocarbons （PAHs） in PM2.5 and PMlo were measured in samples collected at sites in Beijing, China. Their toxic effects on the pulmonary system of rats were investigated. Biochemical parameters （LDH, T-AOC, TP） and inflammatory cytokine（IL-6, IL-1, TNF-a） levels were measured in the lungs of rats exposed to traffic-related PM. Oxidative damage was observed. PM samples were taken from a near road site and an off road site in summer time in 2006. Results The concentrations of the USEPA priority pollutant PAHs in both PMlo and PM2.s were higher （299.658 and 348.412） at the near road site than those （237.728 and 268.472） at the off road site. The similar trend was observed for the concentrations of trace elements in PM. Compared to coarse particles （PM^0）, fine particles （PM2.s） have a greater adsorption capacity to enrich toxic elements than inhalable particles. Decrease in antioxidant capacity and an increase in the amount of lipid peroxidation products in rat lung tissues was observed. Conclusion The findings of the present study suggest that the differing inflammatory responses of PM collected from the two road sites might have been mediated by the differing physicochemical characteristics.

关键词： Traffic-related PM, PAHs Trace elements Pulmonary toxicity

Discovery of the Mid-Late Jurassic volcanic rocks(163.4 Ma) in Nanhuangcheng Island, Shandong Province, China

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China geology 2022年第1期5卷 191-192页

作者： xiao-qing zhu Ming-jian Wang xi Mei zhi-xian Tian Shi-pu Bi Long Huang qingdao Institute of Marine geology China Geological SurveyMinistry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

*** cha.gshan Islands are located on the geographical boundary between the Bohai Sea and the North Yellow Sea,*** tectonic deformation developed in this area,which is an important connection point to study the tectonics of the Shandong Peninsula and Liaoning *** studies have shown that the lithologies of the three northern islands(Beihuangcheng Island,Nanhuangcheng Island,and xiaoqin Island)of the cha.gshan Islands include Neoproterozoic quartzite,phyllite,and slate(Fuzikuang Formation of the Penglai group),and a few areas are covered by Quaternary slope deposits,marine deposits and loess(Fig.1 a;Qiao EW et al.,2019).Recently,a set of volcanic rocks was firstly discovered in Nanhuangcheng Island(Fig.1 a).

关键词： Island Jurassic loess

问题导向的“钢结构设计原理”课堂理论教学改革

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教育教学论坛 2024年第15期 73-76页

作者：朱伟庆刘永健陈峰长安大学公路学院陕西西安710064

“钢结构设计原理”是道路桥路与渡河工程专业的核心专业课程,扎实提升课堂理论教学效率和效果是该课程教学改革的重要任务和目标。细致分析“钢结构设计原理”的课程内容特点以及由此导致学生学习过程中存在的问题,有针对性地提出从多... 详细信息

“钢结构设计原理”是道路桥路与渡河工程专业的核心专业课程,扎实提升课堂理论教学效率和效果是该课程教学改革的重要任务和目标。细致分析“钢结构设计原理”的课程内容特点以及由此导致学生学习过程中存在的问题,有针对性地提出从多层次网格模块化教学内容、建立“思维主线”、引入真实工程案例、坚持精确理论推导与定性分析相结合、开展课程横向比较等方面开展课堂理论教学改革,进而从根本上提升课堂理论教学的效率与效果。

关键词：钢结构设计原理问题导向课程特点模块化思维主线

调控内侧前额叶皮质向丘脑室旁核投射通路对小鼠痛信息传递的影响

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解剖学报 2024年第4期55卷 430-436页

作者：朱柯桦吴凤玲孙寒雪洪洁陈思海史娟李云庆西北工业大学医学研究院西安710072 空军军医大学基础医学院人体解剖学与组织学胚胎学教研室暨梁銶琚脑研究中心西安710032

目的探讨小鼠内侧前额叶皮质(mPFC)-丘脑室旁核(PVT)通路的投射神经元的性质及调控该通路对生理痛和急性痛的影响。方法谷氨酸脱羧酶67-绿色荧光蛋白(gAD67-gFP)基因敲入小鼠3只,用于形态学追踪实验,C57小鼠27只,用于行为学观察实验。... 详细信息

目的探讨小鼠内侧前额叶皮质(mPFC)-丘脑室旁核(PVT)通路的投射神经元的性质及调控该通路对生理痛和急性痛的影响。方法谷氨酸脱羧酶67-绿色荧光蛋白(gAD67-gFP)基因敲入小鼠3只,用于形态学追踪实验,C57小鼠27只,用于行为学观察实验。将霍乱毒素B亚基(CTB)注入gAD67-gFP转基因小鼠的PVT内,观察向PVT投射的mPFC神经元的性质,使用化学遗传学方法调控mPFC-PVT通路,观察其对小鼠机械痛、热痛、冷痛以及辣椒素诱导的急性炎性痛的影响。结果mPFC内CTB标记神经元主要分布于Ⅴ层和Ⅵ层,且与gAD67-gFP不共标;化学遗传学方法激活mPFC-PVT通路可显著降低小鼠的机械痛阈值(PgAba)能的神经通路,激活该通路可促进小鼠的机械痛、热痛和急性炎性痛反应。

关键词：内侧前额叶皮质丘脑室旁核生理痛急性炎性痛化学遗传学小鼠

Inhaled unfractionated heparin improves abnormalities of alveolar coagulation, fibrinolysis and inflammation in endotoxemia-induced lung injury rats

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Chinese Medical Journal 2013年第2期126卷 318-324页

作者： WANg Zong-yu WU Sheng-nan zhu Zhao-zhong YANg ba.xian zhu xi Department of Intensive Care Unit Peking University ThirdHospital Beijing 100191 China Department of Cardiac Surgery Peking University First HospitalBeijing 100034 China Department of Biomedical Engineering Case Western ReserveUniversity Cleveland OH44106-2675 USA Department of Anesthesiology Peking University People'sHospital Beijing 100044 China

background Acute lung injury/acute respiratory distress syndrome presents with not only local inflammation, but also pulmonary coagulopathy which is characterized by an alveolar procoagulant response, anticoagulant inhibition, fibrinolytic supression and fibrin deposition. We thus had hypothesized that if aerosolized unfractionated heparin was inhaled into alveolar spaces, it could block the procoagulant tendency, lessen depletion of coagulation factors, and even influence the inflammatory response. We also assessed the effects of different administration regimens of heparin. Methods Male Wistar rats were given inhaled heparin starting 30 minutes before （prophylactic heparin） or 2 hours after （therapeutic heparin） intravenous lipopolysaccharide （LPS） was administered at 6-hour intervals; control groups received inhaled normal saline with or without being exposed to LPS. Thrombin-antithrombin complexes, activated protein C, tissue type and urokinase type plasminogen activators （t-PA/u-PA）, plasminogen activator inhibitor-1 （PAl-l）, tumor necrosis factor-a, interleukin-6 in bronchoalveolar lavage, and lung tissue myeloperoxidase activity, and histology score were measured at three time-points. PAI-1/（t-PA ＋ u-PA） was calculated based on the before-mentioned parameters. Statistical analysis was made using one-way analysis of variance （ANOVA） with post hoc test or Student＇s t test in the case of heterogeneity of variance. Results An alveolar procoagulant reaction, depressed fibrinolysis, and inflammatory response occurred in endotoxemia-induced lung injury. Local prophylactic application of heparin attenuated coagulation and early inflammation, promoted fibrinolysis, and reduced the histology score. Therapeutic application of heparin had similar, but weaker effects. Conclusions Intrapulmonary application of unfractionated heparin by inhalation might inhibit alveolar procoagulant reaction and the early inflammatory response, promote fibrinolysis, and alleviate pulmonary

关键词： acute lung injury, endotoxemia heparin,administration by inhalation, coagulation

维持性血液透析患者营养素养现状及影响因素分析

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中国血液净化 2024年第2期23卷 157-160页

作者：李伊孟庆兰郝健张利娟朱婷席晓岩武素珍内蒙古医科大学护理学院呼和浩特010000 内蒙古医科大学附属医院医院感染管理科呼和浩特010050 内蒙古医科大学附属医院肾内科呼和浩特010050

目的探讨维持性血液透析(maintenance hemodialysis,MHD)患者营养素养的现状及影响因素。方法选取2023年4月—6月内蒙古医科大学附属医院血液净化中心行MHD的患者200例为研究对象。采用一般资料调查表、社会支持评定量表、血液透析患... 详细信息

目的探讨维持性血液透析(maintenance hemodialysis,MHD)患者营养素养的现状及影响因素。方法选取2023年4月—6月内蒙古医科大学附属医院血液净化中心行MHD的患者200例为研究对象。采用一般资料调查表、社会支持评定量表、血液透析患者自我管理量表、血液透析患者营养素养评价量表进行问卷调查。结果 MHD患者营养素养得分为(19.99±3.72)分。多元线性回归分析显示性别(β=0.142,P=0.003)、文化程度(β=0.188,P=0.001)、居住方式(β=0.112,P=0.020)、每日尿量(β=0.249,P<0.001)、透析龄(β=0.193,P=0.001)、原发疾病(糖尿病)(β=-0.144,P=0.005)、社会支持(β=0.113,P=0.032)、自我管理(β=0.449,P<0.001)是MHD患者营养素养的影响因素。结论 MHD患者营养素养水平处于中等水平,有进一步的提升空间。

关键词：维持性血液透析营养素养自我管理社会支持影响因素

基于掩蔽策略的金属配位水凝胶的制备及其在柔性应力/应变传感领域的潜在应用

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陕西科技大学学报 2024年第2期42卷 25-33页

作者：官小玉郑赛张炳原朱晏霞李东平韩庆鑫陕西科技大学轻工科学与工程学院中国轻工业皮革清洁生产重点实验室陕西西安710021

研究和发展高强高韧金属配位水凝胶(MC-Hg)用于柔性电子传感已成为先进功能高分子材料领域的国际性前沿课题,具有广泛的应用意义和重要的科学价值.然而,传统浸泡法由于金属离子的渗透与结合难以调控,导致力学性能较弱.本论文提出基于乙... 详细信息

研究和发展高强高韧金属配位水凝胶(MC-Hg)用于柔性电子传感已成为先进功能高分子材料领域的国际性前沿课题,具有广泛的应用意义和重要的科学价值.然而,传统浸泡法由于金属离子的渗透与结合难以调控,导致力学性能较弱.本论文提出基于乙酸钠(SA)的掩蔽策略,促使金属配合物先渗透后结合,从而得到均质的金属配位水凝胶(Fe-Hg SA),其断裂强度与韧性(1.546 MPa/2.139 MJ/m^(3))远高于传统浸泡法(0.832 MPa/0.919 MJ/m^(3))以及常用的水溶液重新排列方法(1.126 MPa/1.352 MJ/m^(3)).基于优异的力学性能以及良好的导电性,Fe-Hg SA可潜在应用于柔性应力/应变传感领域.

关键词：金属配位水凝胶柔性电子力学性能

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配水方式对冷却塔热力性能的影响研究

中国水利水电科学研究院学报（中英文） 2024年第4期22卷 353-360页

作者：张爱军宋小军刘涛朱晴马志伟李陆军中国电力工程顾问集团西北电力设计院有限公司陕西西安710075 中国水利水电科学研究院北京100038

为了研究电厂在调峰影响下低负荷运行时合理的配水方式,探寻冷却塔“带水”检修的可能性,采用三维数值模拟方法,计算了某高位收水冷却塔两机六泵全塔配水、一机三泵全塔外围配水和一机三泵半塔配水方式下的塔内外流场特性及热力性能。... 详细信息

为了研究电厂在调峰影响下低负荷运行时合理的配水方式,探寻冷却塔“带水”检修的可能性,采用三维数值模拟方法,计算了某高位收水冷却塔两机六泵全塔配水、一机三泵全塔外围配水和一机三泵半塔配水方式下的塔内外流场特性及热力性能。分析了外围配水和半塔配水可能存在的进塔空气全部从未淋水区域的填料流过而不与淋水填料换热的问题,并统计了配水方式对冷却能力的影响。结果表明,外围配水、半塔配水虽然不存在进塔空气全部从未淋水区域的填料流过的情况,但分区配水热力性能易受到环境风影响,在改善电厂调峰低负荷运行条件下的冷却塔热力性能方面起负面效果。

关键词：高位收水冷却塔热力性能环境风分区配水数值模拟