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Copper-catalyzed Ullmann-type synthesis of diaryl ethers assisted by salicylaldimine ligands

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Chinese Chemical Letters 2014年第2期25卷 337-340页

作者： Cun-Wei Qian Wen-Lin Lv Qian-Shou Zong mao-yuan wang Dong Fang School of Chemistry and Chemical Engineering Yancheng Teachers University School of Biological and Chemical Engineering Jiaxing University

A series of salicylaldimine ligands were designed to promote the copper-catalyzed Ullmann cross- coupling reaction. After a screening process, 2-（（2-isopropylphenylimino）methyl）phenol was found to serve as a good supporting ligand for this reaction. Employing this Schiff-base ligand as a new supporting ligand, the copper-catalyzed coupling reactions of aryl bromides and aryl iodides with various phenols successfully proceeded in good yields under mild conditions. Various diaryl ethers were obtained with excellent yields in dioxane in the presence of K3P04 and a catalytic amount of copper（I） salt.

关键词： Copper catalyst Salicylaldimine ligands Ullmann coupling Diaryl ethers

Ionic Conduction and Fuel Cell Performance of Ba0.98Ce0.8Tm0.2O3-α Ceramic

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Chinese Journal of Chemical Physics 2010年第6期23卷 707-712,746页

作者：仇立干王茂元盐城师范学院化学化工学院盐城224051

The perovskite-type oxide solid solution Ba0.98Ce0.8Tm0.2O3-α was prepared by high temperature solid-state reaction and its single phase character was confirmed by X-ray diffraction. The conduction property of the sample was investigated by alternating current impedance spectroscopy and gas concentration cell methods under different gases atmospheres in the temperature range of 500-900 ℃. The performance of the hydrogen-air fuel cell using the sample as solid electrolyte was measured. In wet hydrogen, the sample is a pure protonic conductor with the protonic transport number of 1 in the range of 500-600 ℃, a mixed conductor of proton and electron with the protonic transport number of 0.945-0.933 above 600 ℃. In wet air, the sample is a mixed conductor of proton, oxide ion, and electronic hole. The protonic transport numbers are 0.010-0.021, and the oxide ionic transport numbers are 0.471-0.382. In hydrogen-air fuel cell, the sample is a mixed conductor of proton, oxide ion and electron, the ionic transport numbers are 0.942 0.885. The fuel cell using Ba0.98Ce0.8Tm0.2O3-α as solid electrolyte can work stably. At 900 ℃, the maximum power output density is 110,2 mW/cm2, which is higher than that of our previous cell using Ba0.98Ce0.8Tm0.2O3-α （x〈≤1, RE=Y, Eu, Ho） as solid electrolyte.

关键词： Ba0.98Ce0.8Tm0.2O3-α Ionic conduction Gas concentration cell Alternating current impedance Fuel cell

加拿大流动儿童城市社会融入问题与解决策略研究

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民族教育研究 2016年第5期27卷 92-101页

作者：杨茂庆王远广西师范大学教育学部广西桂林541004 郑州市教育科学研究所河南郑州450007

在全球化背景下世界开放程度越来越高,国际间人口流动成为新常态,加拿大流动儿童不断涌入城市社会,其来源也日趋多样化。加拿大作为奉行多元文化主义的移民国家,流动儿童城市社会融入对其未来发展具有重要影响。教育融入、文化融入和心... 详细信息

在全球化背景下世界开放程度越来越高,国际间人口流动成为新常态,加拿大流动儿童不断涌入城市社会,其来源也日趋多样化。加拿大作为奉行多元文化主义的移民国家,流动儿童城市社会融入对其未来发展具有重要影响。教育融入、文化融入和心理融入是流动儿童城市社会融入的三个主要维度。在城市融入过程中,加拿大流动儿童面临的主要问题有语言多样性背景下的教育困境,文化差异下的学校教育适应障碍,偏见与文化隔阂下的对立冲突,制度障碍下的社会服务缺失,环境适应困境下的心理问题等。加拿大通过发展灵活多样的双语教育,建立基于家、校、社区多方合作的教育融入机制,促进流动儿童双重身份的社会认同,构建全面的移民社会融入服务体系和建立完善的心理干预机制等,以帮助流动儿童融入城市社会。这将为我国进城务工人员随迁子女的城市社会融入提供有益借鉴。

关键词：加拿大流动儿童社会融入多元文化

Effects of HiLo on HIF-1αprotein and VEGF mRNA expressions in the skeletal muscle

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Effects of HiLo on HIF-1αprotein and VEGF mRNA expressions ...

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

中国生理学会第23届全国会员代表大会暨生理学学术大会

作者： Shan-Shan mao~*,Rui-yuan wang Beijing Sport University,Beijing 100084,China

Introduction:As a hypoxia inducing nuclear transcription factor,hypoxia inducible factor-1(HIF-1) elicits responses to hypoxia in cells by regulating the transcription of hypoxia responsive genes,such as vascular endothelial growth factor(VEGF).Many studies suggest that HIF-1 may play a key role both in activating beneficial and inversing adverse effects on hypoxia ***(living high,training low) is a popular hypoxia training *** purpose of the study is to investigate how HiLo affects HIF-1αprotein and VEGF mRNA expressions in the skeletal ***:80 7-week-old male SD Rats are randomly assigned to 4 groups:controls(C), hypoxic controls(HC),hypoxic training(HT) and normoxic training(NT).Each group is divided into 3 teams,the 4-day team,7-day team and 28-day team.A HiLo model is designed to simulate living at 4 000 m altitude while trains under normoxia with middle-intensity-load(treadmill slope 10°,speed 20 m/min,one bout per day,5 bouts per week and 1 h per bout).Immunology and molecular biology methods are employed to measure the HIF-1αprotein and VEGF mRNA expressions in the gastrocnemii of experimental *** and Conclusions:(1) During the 4-week HiLo,both HIF-1αprotein and VEGF mRNA expressions show a dynamic trend:reaching to a high level within 7 days then attenuating to a level significantly higher than the baseline on 28th day(P<0.01).(2) Expressions of HIF-1αprotein and VEGF mRNA depend on both hypoxia stimulus and durations,especially the former.(3) Both HIF-1αprotein and VEGF mRNA expressions are early rapid effects in HiLo.(4) These suggest that HiLo induces the transcription of VEGF through HIF-1αprotein,the core of O-sensing pathway.

关键词： HiLo HIF-1αprotein VEGF mRNA

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng wang Guo-Cui mao Hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

理气化痰活血方药对大鼠冠脉微血管血栓形成及阻塞的影响

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中国医学科学院学报 2016年第3期38卷 260-264页

作者：王贤良苏立硕毛静远王帅赵国元王聪天津中医药大学第一附属医院心血管科天津300193

目的复制大鼠冠脉微血管血栓形成的动物模型,考察理气化痰活血方药对大鼠冠脉微血管血栓形成及血栓阻塞的影响。方法将清洁级健康雄性SD大鼠125只[体重为(300±25)g]顺序编号,采用抽签法随机分为治疗组(n=60)、对照组(n=60)及空白组(n=... 详细信息

目的复制大鼠冠脉微血管血栓形成的动物模型,考察理气化痰活血方药对大鼠冠脉微血管血栓形成及血栓阻塞的影响。方法将清洁级健康雄性SD大鼠125只[体重为(300±25)g]顺序编号,采用抽签法随机分为治疗组(n=60)、对照组(n=60)及空白组(n=5)3组,治疗组和对照组大鼠均通过经心尖部向左心室内注射月桂酸钠建立大鼠冠脉微血管血栓形成动物模型,治疗组术前1 d及术后给予理气化痰活血方药灌胃(1 ml/100 g,每日1次),对照组术前1 d及术后给予蒸馏水灌胃(1 ml/100 g,每日1次),两组分别在术后1、24 h,7、14、21、28 d各时间点随机处死5只大鼠,并留取心肌组织;空白组5只大鼠不予任何处理,正常饲养,在28 d时一并处死,留取心肌组织。心肌组织标本经HE染色制作病理切片,观察比较各组大鼠各时间点冠脉微血管血栓形成及微血管血栓阻塞情况。结果治疗组和对照组大鼠经心尖部注射月桂酸钠后1 h即有冠脉微血管血栓形成,24 h左右血栓形成率最高;与空白组比较,治疗组和对照组冠脉微血管均出现不同程度的阻塞情况。治疗组术后各时间点冠脉微血管血栓形成率均明显低于对照组(P<0.05或P<0.01);治疗组冠脉微血管血栓阻塞程度明显轻于对照组(P<0.05或P<0.01)。结论通过注射月桂酸钠可以成功诱导大鼠冠脉微血管血栓形成。理气化痰活血方药可减少大鼠冠脉微血管血栓形成,同时可改善大鼠冠脉微血管血栓阻塞程度。

关键词：冠脉微循环理气化痰活血方药微血管血栓形成微血管阻塞

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加热时间对滚塑制品性能的影响

塑料科技 2017年第2期45卷 55-58页

作者：温原毛宪朋汪永志浙江瑞堂塑料科技有限公司浙江宁波315323 安徽锐途滚塑科技有限公司安徽合肥231131

使用滚塑级线型低密度聚乙烯(LLDPE)粉末,研究了加热时间对滚塑制品性能的影响。结果表明:在滚塑成型工艺中,存在最佳加工温度区间,且该区间位于凝结段;对于滚塑制品的断裂伸长应变和弯曲模量,在消泡段存在"加热陷阱",应尽量避免在这一... 详细信息

使用滚塑级线型低密度聚乙烯(LLDPE)粉末,研究了加热时间对滚塑制品性能的影响。结果表明:在滚塑成型工艺中,存在最佳加工温度区间,且该区间位于凝结段;对于滚塑制品的断裂伸长应变和弯曲模量,在消泡段存在"加热陷阱",应尽量避免在这一温度区间进行加工。

关键词：滚塑成型线型低密度聚乙烯最佳加工温度区间加热陷阱加热时间

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

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Neural Regeneration Research 2025年第1期20卷 67-81页

作者： Yubo wang Tingli yuan Tianjie Lyu Ling Zhang Meng wang Zhiying He Yongjun wang Zixiao Li Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Shanghai Engineering Research Center of Stem Cells Translational Medicine ShanghaiChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghaiChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger ***,in particular,bears a high burden of stroke *** recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its *** review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and ***,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell ***,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient *** cell therapy may potentially become an important component of ischemic stroke treatment.

关键词： cell therapy immune cell inflammatory ischemic stroke stem cell

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng Cai Shengjun Miao yuan Li Yu wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification