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Effects of Dendritic Orientation on Stress Rupture Properties of DD6 Single Crystal Superalloy

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Journal of Iron and Steel Research International 2011年第10期18卷 66-71页

作者： shi zhen-xue li Jia-rong liU shi-zhong ZHAOJin-qian National Key Laboratory of Science and Technology on Advanced High Temperature Structural Materials Beijing Institute of Aeronautical Materials Beijing 100095 China

DD6 single crystal superalloy slabs were prepared with seed method in the direetionally solidified furnace with high temperature gradient. The transverse stress rupture properties and fracture hehaviour of the alloy at 760 ℃/758 MPa, 850 ℃/550 MPa and 980 ℃/250 MPa were investigated and compared with those of longitudinal specimens. The transverse stress rupture lives are corresponding with the longitudinal stress rupture lives at 760 ℃/758 MPa and 850 ℃/550 MPa. The transverse stress rupture lives are slightly less than the longitudinal stress rupture lives at 980 ℃/ 250 MPa. The fracture mechanism of the transverse stress rupture of the alloy at 760 ℃/758 MPa shows quasi-cleav- age mode and the fracture mechanism at 980 ℃/250 MPa shows dimple mode, while the fracture mechanism at 850 ℃/ 550 MPa shows quasi-cleavage and dimple mixture mode. At higher temperature and lower stress, the microeracks are easier to initiate and interconnect in the transverse specimen than those in longitudinal specimen because there are interdendritic regions perpendicular to the axis of stress.

关键词： DD6 single crystal superalloy stress rupture property fracture behaviour

Central cell:the key to determine persistent pollen tube attraction or termination

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Science China(life Sciences) 2024年第9期67卷 2030-2032页

作者： Jiang-Guo Meng shi-zhen li Hong-Ju li Center for Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation Integrative Science Center of Germplasm Creation Western China(Chongqing)Science CitySchool of Life SciencesSouthwest UniversityChongqing400715 China Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Center for Molecular Agrobiology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China

Most eukaryotic species depend on sexual reproduction,characterized by fertilization,to produce a new *** process requires the transfer of sperm(male gamete),containing half of the genetic information,from the male to the egg cell(female gamete),which holds half of the maternal genome,within the female reproductive *** strategies have been evolved to ensure fertilization success in plants.

关键词： organs termination holds

Quality of life after pancreatic surgery

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World Journal of Gastroenterology 2024年第8期30卷 943-955页

作者： shi-zhen li Ting-Ting zhen Yi Wu Min Wang Ting-Ting Qin Hang Zhang Ren-Yi Qin Department of Biliary-Pancreatic Surgery Affiliated Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Pancreatic surgery is challenging owing to the anatomical characteristics of the *** attention has been paid to changes in quality of life(QOL)after pancreatic *** To summarize and analyze current research results on QOL after pancreatic *** A systematic search of the literature available on PubMed and EMBASE was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** studies were identified by screening the references of retrieved *** on patients’QOL after pancreatic surgery published after January 1,2012,were *** included prospective and retrospective studies on patients'QOL after several types of pancreatic *** results of these primary studies were summarized *** A total of 45 articles were included in the study,of which 13 were related to pancreaticoduodenectomy(PD),seven to duodenum-preserving pancreatic head resection(DPPHR),nine to distal pancreatectomy(DP),two to central pancre-atectomy(CP),and 14 to total pancreatectomy(TP).Some studies showed that 3-6 months were needed for QOL recovery after PD,whereas others showed that 6-12 months was more *** TP and PD had similar influences on QOL,patients needed longer to recover to preoperative or baseline levels after *** QOL was better after DPPHR than ***,the superiority of the QOL between patients who underwent CP and PD remains *** decrease in exocrine and endocrine functions postoperatively was the main factor affecting the *** invasive surgery could improve patients’QOL in the early Core Tip:This review summarizes and analyzes current research results on quality of life(QOL)after pancreatic *** article covers the discussion and analysis of the QOL of various pancreatic *** kind of surgical procedure has better QOL is *** long-term benefits on QOL of minimally invasive su

关键词： Quality of life Pancreaticoduodenectomy Duodenum-preserving pancreatic head resection Distal pancreatectomy Central pancreatectomy Total pancreatectomy

Role of Prosurvival Molecules in the Action of lidamycin toward Human Tumor Cells

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Biomedical and Environmental Sciences 2009年第3期22卷 244-252页

作者： A-JING YANG WEI-WEI shi YONG li zhen WANG RONG-GUANG SHAO DIAN-DONG li QI-YANG HE Institute of Medicinal Biotechnology Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100050 China

Objective lidamycin, an enediyne antibiotic, leads to apoptosis and mitotic cell death of human tumor cells at high and low concentrations. The reason why tumor cells have distinct responses to lidamycin remains elusive. This study was to elucidate if cellular prosurvival molecules are involved in these responses. Methods Cleavage of chromatin and DNA was observed by chromatin condensation and agarose gel electrophoresis. Accumulation of rhodamine 123 in lidamycin-treated cells was assayed by flow cytometry. Cell multinucleation was detected by staining with Hoechst 33342. Western blot and senescence-associated β-galactosidase （SA-β-gal） staining were used to analyze protein expression and senescence-like phenotype, respectively. Results SIRT1 deacetylase remained unchanged in 0.5 nmol/L lidamycin whereas cleavage occurred when apoptosis was induced by lidamycin. Increased FOXO3a, SOD-1 and SOD-2 expression and transient phosphorylation of ERK were detected after exposure of human hepatoma BEL-7402 cells to 0.5 nmol/L lidamycin. High expressions of SIRT1 and Akt were found in colon carcinoma HCT116 p53 knock-out cells exposed to lidamycin. Degradation of PARP and p53 by lidamycin as a substitute for SIRT1 and Akt was confirmed with caspase inhibitor Q-VD-OPh and proteasome inhibitor MG132. Resistance to lidamycin-induced DNA cleavage was observed in breast cancer doxorubicin-resistant MCF-7 cells. This was not induced by P-glycoprotein as no accumulation of rhodamine 123 was detected in the resistant cells following exposure to lidamycin. In contrast to sensitive MCF-7 cells, a lower multinucleation rate for the resistant cells was measured following exposure to equal concentrations of lidamycin. Conclusions Cellular prosurvival molecules, such as SIRTI, Akt, SOD-1, SOD-2 and other unknown factors can influence the action of lidamycin on human tumor cells.

关键词： lidamycin Prosurvival molecules SIRTI deacetylase Apoptosis Mitotic cell death Multidrug resistance

Change monitoring of earth rotation parameter with Maglev gyroscope precessional torque

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中国有色金属学会会刊：英文版 2011年第S3期21卷 589-593页

作者： YANG Zhi-qiang, GONG Yun, shi zhen, li Yun Geological Engineering and Geomatics Institute, Chang’an University, Xi’an 710054, China Geological Engineering and Geomatics Institute Chang'an University Xi'an 710054 China

Through analyzing the relationship between gyro dynamic torques produced by the changes of earth rotation parameters (ERP), a method of measuring the earth rotation parameters was proposed and explored by using gyroscope. The preliminary experiments were carried out using GAT Maglev Gyro Station (which is self-developed by China). Considering the measurement and expanding-application of the earth rotation parameters, some ideas and opinions about the structure design, measurement methods and data processing of gyro were proposed, and some outlook of the expanding-application of the gyroscope in geodetic and geophysical fields were done. The experimental results show that using the high-precision gyroscope to determine the changes of ERP is feasible, with the emergence of ultra-high precision gyro; it is possible for determining the earth rotation parameters by gyro in stead of by current complex space surveying technology.

关键词： Maglev gyroscope earth rotation parameters (ERP) precessional torque pole motion length of day

Mechanical Properties of Railway High-strength Manufactured Sand Concrete: Typical lithology, Stone Powder Content and Strength Grade

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 194-203页

作者： WANG zhen li Huajian HUANG Fali YANG Zhiqiang WEN Jiaxin shi Henan Railway Engineering Research Institute China Academy of Railway Science Corporation LimitedBeijing 100081China State Key Laboratory for Track Technology of High-Speed Railway Beijing 100081China

In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as *** evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are *** to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of *** powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed.

关键词： manufactured sand concrete railway mechanical property lithology stone powder content

Tectonic evolution and accumulation characteristics of Carboniferous shale gas in Yadu-Ziyun-Luodian aulacogen, Guizhou Province, South China

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China Geology 2023年第4期6卷 646-659页

作者： Kun Yuan Wen-hui Huang Ting Wang shi-zhen li Xiang-can Sun Xin-xin Fang Jun-ping Xiao Jun Guo Oil and Gas Resources Survey China Geological SurveyMinistry of Natural ResourcesBeijing 100083China China University of Geosciences(Beijing) Beijing 100083China The key Laboratory of Unconventional Oil and Gas Geology China Geological SurveyBeijing 100083China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China No.814 Geological Party East China Bureau of Mineral Exploration and DevelopmentZhenjiang 212005China Hunan Institute of Geophysics and Geochemistry Changsha 410000China

The Yadu-Ziyun-Luodian aulacogen(YZLA) developed into being NW-trending in the Late Paleozoic,and was considered as an important passive continental margin aulacogen in Guizhou Province, South China. This tectonic zone is considered a large intracontinental thrust-slip tectonic unit, which has undergone a long period of development. It was ultimately determined in the Yanshanian, where the typical Upper Paleozoic marine shales were deposited. In 2021, Well QSD-1 was deployed in the liupanshui area at the northwest margin of the aulacogen, and obtained a daily shale gas flow of 11011 m3in the Carboniferous Dawuba Formation. It thus achieved a breakthrough in the invesgation of shale gas in the Lower Carboniferous in South China, revealing relatively good gas-bearing properties and broad exploration prospects of the aulacogen. Being different from the Lower Paleozoic strata in the Sichuan Basin and the Yichang area of the Middle Yangtze, the development of the Carboniferous Dawuba Formation in the aulacogen exhibits the following characteristics:(1) The Lower Carboniferous shale is thick and widely distributed, with interbedded shale and marlstone of virous thickness;(2) The total organic carbon(TOC) content of the shale in the Dawuba Formation ranges from 1% to 5%, with an average of 2%, and the thermal maturity of organic matter(Ro) varies from 1% to 4%, with an average of2.5%, indicating good hydrocarbon generation capacity;(3) The main shale in the aulacogen was formed during the fault subsidence stage from the Middle Devonian to the Early Permian. Although the strong compression and deformation during the late Indosinian-Himalayan played a certain role in destroying the formed shale gas reservoirs, comparative analysis suggests that the area covered by the current Triassic strata has a low degree of destruction. It therefore provides good conditions for shale gas preservation,which can be regarded as a favorable area for the next exploration.

关键词： Shale gas Aulacogen Carboniferous Shale and marlstone Organic carbon Organic matter Hydrocarbon generation capacity Tectonic evolution Accumulation characteristics

Geochemical characteristics and sedimentary environment of the Middle Devonian organic-rich shales in the Northwest of Guizhong Depression, Southwest China

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China Geology 2020年第4期3卷 567-574页

作者： Kun Yuan Wen-hui Huang Xin-xin Fang shi-zhen li Ting Wang Tuo lin Guo-heng liu China University of Geosciences(Beijing) Beijing 100083China Oil and Gas Resources Survey China Geological SurveyMinistry of Natural Resources Beijing 100083China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

In order to figure out the redox conditions and paleo-sedimentary environment of the Middle Devonian shales in the northwest of Guizhong Depression,the trace element analysis was conducted on the Middle Devonian cores(320.35–938.50 m)of the typical shale gas investigation well(GY-1)at a 1.50 m sampling interval through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).According to the test result,the average values of V/(V+Ni),V/Cr and Ni/Co in Nabiao formation(Fm.)are larger than 0.67,4.65 and 7.71 respectively,and Nabiao *** rich in biological assemblages such as tabasheer,ammonite,*** evidences indicate the rising sea level rose relatively in the sedimentation period of Nabiao *** a deepwater shelf environment,which was favorable for the preservation of organic *** V/(V+Ni),V/Cr and Ni/Co in Luofu *** Tangting *** 0.38–0.65,0.73–4.10 and 3.70–6.72 respectively,indicating that the sea level dropped relatively in their sedimentation period,during which the water bodies became shallow,and the sedimentary environment was a weak oxidizing shallow water shelf *** addition,the variation of TOC has a high correlation with the enrichment degree of Ba element,indicating the favorable conditions for the enrichment and preservation of organic matters under an oxygen-deficient ***,according to the identification of trace element indexes,the northwest of Guizhong Depression experienced the sedimentary cycle of relative rise to relative fall of sea level from bottom to top in the Middle Devonian sedimentation *** relative sea level rose to the highest in the sedimentation period of Nabiao Fm.,in which the organic-rich shales with stable thickness and high organic content were ***,the Nabiao *** be regarded as the favorable exploration target interval in this area.

关键词： Organic-rich shale Devonian Geochemistry Sedimentary environment Guizhong Depression Geological survey engineering Guizhou Province Southwest China

Geological conditions and reservoir characteristics of various shales in major shalehosted regions of China

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China Geology 2024年第1期7卷 138-149页

作者： Shu-jing Bao Tian-xu Guo Jin-tao Yin Wei-bin liu Sheng-jian Wang Hao-han li Zhi Zhou shi-zhen li Xiang-lin Chen The Key Laboratory of Unconventional Petroleum Geology China Geological SurveyMinistry of Natural Resources100083 BeijingChina Oil and Gas Survey China Geological Survey100083 BeijingChina Research Institute of Yanchang Petroleum(Group)CO.LTD 710076 Xi’anChina

China is home to shales of three facies:Marine shale,continental shale,and marine-continental transitional *** types of shale gas are associated with significantly different formation conditions and major controlling *** study compared the geological characteristics of various shales and analyzed the influences of different parameters on the formation and accumulation of shale *** general,shales in China’s several regions exhibit high total organic carbon(TOC)contents,which lays a sound material basis for shale gas *** strata generally show high degrees of thermal *** contrast,continental shales manifest low degrees of thermal evolution,necessitating focusing on areas with relatively high degrees of thermal evolution in the process of shale gas surveys for these *** shales of the Wufeng and Silurian formations constitute the most favorable shale gas reservoirs since they exhibit the highest porosity among the three types of *** shales are followed by those in the Niutitang and Longtan *** contrast,the shales of the Doushantuo,Yanchang,and Qingshankou formations manifest low ***,the shales of the Wufeng and Longmaxi formations exhibit high brittle mineral *** a low siliceous mineral content,the shales of the Doushantuo Formation feature a high carbonate mineral content,which can increase the shales’brittleness to some *** marine-continental transitional shales,where thin interbeds of tight sandstone with unequal thicknesses are generally found,it is recommended that fracturing combined with drainage of multiple sets of lithologic strata should be employed to enhance their shale gas production.

关键词： Shale gas Marine shale Continental shale Marine-continental transitional shale Neoproterozoic-Cretaceous strata Geological conditions Reservoir characteristics Petroleum geological survey engineering