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Microstructure analysis of deep rock in Meilinmiao Mine

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 468-473页

作者： Ren-Liang SHAN Li-Wei SONG Yan LIU wen-feng ZHAO hui-Xian CHEN School of Mechanics and Civil Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

SEM tests were conducted on four kinds of typical deep rocks in Meilinmiao Mine, and the micro properties were analyzed. The particles of gritstone are unbroken and particle diameter ranges from 80 lam to 400 pro, and the void between particles is wide. The macroscopic failure of gritstone is caused by breakage of the dung distributed between particles, and po- tassium feldspars contained in gritstone are not leached. The failure of medium sandstone is caused by micro cracks distributed in sandstone particles, and potassium feldspars are leached seriously, so the pores penetrate each other and there is close hy- draulic connection in medium sandstone. The particles of fine sandstone are broken, and the particle diameters range from 60 pm to 300 pm, which determines the pores have good connectivity between particles. The dolomites contained in fine sand- stone are corroded, and the micro fracture form belongs to inter-granular fracture. There are no particles and blocks in micro- structure of sandy mudstone, but there are diverse micro cracks. The failure of mudstone arises from the extension of micro cracks, and the microstructure is different from the other three kinds of sandstones obviously.

关键词： SEM test deep rock microstructure leaching crack

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第1期68卷 201-208页

作者： hui-feng Wang wen-Jie Shi Yu-Xin Yang Bao-Xia Dong Tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

关键词： metal-organic frameworks dinuclear metal centers synergistic catalysis CO2 reduction photocatalysis

Role of radial artery in total arterial myocardial revascularization in coronary bypass surgery

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Chinese Medical Journal 2008年第3期121卷 200-204页

作者： CHEN Xu-jun ZHANG Yong CHEN Xin feng wen-hui LI Da-lian LI Hong-wei Department of Cardiac Surgery Cardiovascular Center BeijingFriendship Hospital Capital Medical University Beijing 100050China Department of Cardiac Surgery Beijing Military General HospitalBeijing 100700 China Department of Thoracic and Cardiovascular Surgery Nanjing FirstHospital Nanjing Medical University Nanjing Jiangsu 210006China

Background Total arterial revascularization （TAR） was widely utilized in coronary artery bypass grafting （CABG） as a result of its better long-term effect compared with vein grafts. Of the arterial conduits, radial artery （RA） gained popularity for its easy availability and reported long-term patency. Thus, the objective of this study was to investigate the effect of RA in TAR in CABG. Methods From January 2000 to December 2006, 85 patients （56 male and 29 female） at a mean age of 57.0 ± 5.2 years, underwent TAR in CABG. RA and left internal mammary artery （LIMA） with composite Y or T and sequential grafting techniques were used. Post-operative complications were recorded and follow-up was performed. Results Eighty-five LIMA and 149 RA grafts including 21 single and 64 bilateral RA were collected. A total of 87 distal anastomoses were done with the LIMA and another 152 were done with the RA, with the mean number of distal anastomosis per patient of 2.81 ± 0.47. The proximal RA ends were anastomsed directly to the aorta in 140 grafts with Y or T graft off in situ LIMA in 9, Y or T graft off RA in 9. The distal end was anastomsed to right coronary artery system in 92 to obtuse margina in 46, to diagonal in 19 and to ramous intermedius in 5. Nine sequential anastomoses were performed with RA. Nine composite Y or T grafts were constructed with RA and LIMA while another 9 were constructed with RA and RA. One （1.2%） patient died, 3 patients （3.5%） experienced acute renal failure and 2 （2.4%） developed stroke. All patients were still alive and no patient had evidences of newly occurred myocardial infarction or angina after a mean follow-up of 36.5 ＋ 4.1 months （6-67 months）. Postoperatively at 6 month, mean left ventricular ejective fraction was increased to 0.49 ±0.09, compared with that of 0.43 ± 0.11 preoperatively （P=-0.027）. Postoperative mean New York Heart Association class was 2.5±0.5, compared with that of 3.0±0.4 preoperatively （P=-0.003）. Conclusions TAR w

关键词： radial artery coronary artery bypass total arterial revascularization

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工序尺寸换算中假废品的判定及补救措施研究

工程设计学报 2021年第1期28卷 33-40页

作者：冯文慧马晓三黄河交通学院机电工程学院河南焦作454950 河南理工大学机械与动力工程学院河南焦作454000

在工艺基准和设计基准不重合的情况下,在零件加工过程中采用极值法计算工艺尺寸链时经常会出现工序尺寸不合格而最终设计尺寸可能合格的“假废品”现象。为此,以工艺尺寸链极值法计算的特点为基础,对假废品产生的原因进行了分析。为了... 详细信息

在工艺基准和设计基准不重合的情况下,在零件加工过程中采用极值法计算工艺尺寸链时经常会出现工序尺寸不合格而最终设计尺寸可能合格的“假废品”现象。为此,以工艺尺寸链极值法计算的特点为基础,对假废品产生的原因进行了分析。为了便于在零件加工过程中判定假废品,通过将工序尺寸作为封闭环尺寸,建立并计算新的尺寸链,得到间接保证设计尺寸合格的必要不充分条件,并结合先于工序尺寸生成的组成环尺寸的实际偏差,提出了一种新的判定假废品工序尺寸公差范围的计算方法和流程。为了避免假废品转化为设计尺寸不合格的真废品,提出了一种对后续加工尺寸进行公差压缩的补救措施。根据工艺尺寸链中各组成环尺寸的相互补偿关系,分析了后续加工工序中公差压缩后尺寸极限偏差和公差的计算方法和流程。研究结果可为实际生产中假废品的判定和补救提供指导。

关键词：假废品工序尺寸工艺尺寸链极值法补救措施

Effect of matrine hydrochloride on liver injury

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Effect of matrine hydrochloride on liver injury

两岸三地药理学与临床药理学术会议

作者： CHEN Li-bo XU feng MA wen-hui (Shenyang Pharmaceutical University, Shenyang 110016, China)

Objective Searching the function that the Injection of the matrine hydrochloride prevents and cures acute chemical liver injury of mice、immunity liver injury of mice and chronic liver injury of rats. Methods Acute hepatic injury models of mice induced by Chemical poison carbon tetrachloride (CCl), thioacetamide(TAA),D-galactosamine(D-GalN),immunity hepatic injury model of mice induced by BCG and fat polysaccharide (LPS),chronic liver injury model of rats induced by CCl were introduced in the ex- *** serum ALT and AST were measured in acute hepatic injury *** ALT,AST, AKP,ALB,TP,BiL-T,creatinine,triglyceride,sialic acid,laminin,hyaluronic acid,typeⅢprocollagen and typeⅣcollagen,hepatic hydroxyproline (HyP) of rats in chronic liver injury animals were determined after Injection of the matrine *** The Injection of the matrine hydrochloride reduced serum ALT and AST level of acute chemical liver injury of mice induced by CCl,TAA and *** index of the liver and the spleen of immunity liver injury of mice induced by BCG and LPS were decreased after the injection of matrine hydrochloride *** with the model group,the injection may obviously inhibited serum ALT,AST,TP,AKP,TRI,BiL-T,creatinine,triglyceride,sialic acid,laminin,hyaluronic acid,typeⅢprocollagen and typeⅣcollagen activity of chronic liver injury of rats induced by CCl,elevat- ed ALB、A/G,reduced the liver HyP,decreased the index of the liver and the *** liver visual obser- vation,the pathology inspection and the HAI grading result showed the injection may reduce the inflamma- tory activity in liver tissue,restrain the liver cell damage,reduce the pseudolobuli *** The Injection of matrine hydrochloride had the protective function to acute chemical hepatic injury of mice induced by CCl、TAA、D-GalN、immunity hepatic injury of mice induced by the BCG and LPS and chronic liver injury of rats induced by CCl.

关键词： injection of the matrine hydrochloride hepatic injury hepatic cell protection

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基于独立成分分析的数字水印研究

河南师范大学学报（自然科学版） 2009年第3期37卷 127-129页

作者：冯文惠郭秀峰河南商业高等专科学校计算机系郑州450044

提出了一种新的利用独立成分分析提取数字水印的方法,把原始图像和数字水印图像在空间域直接混叠,得到两个嵌入水印的图像.通过对混合矩阵的控制实现水印的不可见性.把混合后的图像作为盲源进行分离,在整个提取过程中不需要原始图像和... 详细信息

提出了一种新的利用独立成分分析提取数字水印的方法,把原始图像和数字水印图像在空间域直接混叠,得到两个嵌入水印的图像.通过对混合矩阵的控制实现水印的不可见性.把混合后的图像作为盲源进行分离,在整个提取过程中不需要原始图像和混合矩阵信息.仿真实验表明该方案很好的实现了水印的不可见性和鲁棒性的统一.

关键词：数字水印独立成分分析 FastICA 盲源分离

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工序尺寸换算中虚公差的产生原因及处理方法

食品与机械 2021年第10期37卷 93-97页

作者：冯文慧马晓三黄河交通学院机电工程学院河南焦作454950 焦作市物料输送设备关键件制造工艺与装备工程技术研究中心河南焦作454950 河南理工大学机械与动力工程学院河南焦作454000

目的:避免工序尺寸换算过程中虚公差现象的产生,提高机械零件加工工艺规程的可执行性。方法:以工艺尺寸链计算中封闭环与各组成环之间的公差分配关系和误差补偿关系为基础,对零件工艺基准和设计基准不重合条件下工序尺寸虚公差产生的原... 详细信息

目的:避免工序尺寸换算过程中虚公差现象的产生,提高机械零件加工工艺规程的可执行性。方法:以工艺尺寸链计算中封闭环与各组成环之间的公差分配关系和误差补偿关系为基础,对零件工艺基准和设计基准不重合条件下工序尺寸虚公差产生的原因和工艺尺寸链的改进方法进行了研究。结果:从封闭环的选择、已知组成环尺寸公差的合理压缩以及根据其他组成环尺寸的实际偏差确定工序尺寸公差3方面,提出了工艺尺寸链处理和改进方法。结论:从以上3方面对工艺尺寸链进行处理和改进,可有效避免工序尺寸虚公差现象的发生。

关键词：虚公差工序尺寸工艺尺寸链公差压缩实际偏差

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期7卷 112-119页

作者： Jia-hui Li Qing Zhao Dong-Ao Mao Kun Zhou Bao-Kuan Chen Yan-feng Bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

关键词： Modular construction Photothermal conversion Polyoxometalate Thiacalixarene

Effect of Ginsenoside Re on shock

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Effect of Ginsenoside Re on shock