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资源-环境治理视阈下中国构建北极命运共同体的角色定位与现实应因
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作者 曲亚囡 杨宇涵 《海洋开发与管理》 2023年第7期13-21,共9页
近年来,受到全球气候变暖和科学技术进步的影响,北极资源开发变得更加容易,各国纷纷加入北极资源开发的大潮中,但由此导致的环境问题也日益凸显。在此背景下,资源-环境治理体系应运而生,它是构建北极命运共同体的理论创新、重要支点以... 近年来,受到全球气候变暖和科学技术进步的影响,北极资源开发变得更加容易,各国纷纷加入北极资源开发的大潮中,但由此导致的环境问题也日益凸显。在此背景下,资源-环境治理体系应运而生,它是构建北极命运共同体的理论创新、重要支点以及现实需求。基于此理论,中国以北极利益攸关者、北极资源开发者以及北极环境保护贡献者的身份积极参与构建北极命运共同体。但在此过程中也受到地缘政治、北极争议、自身不足等多种挑战,需要打造紧密的中国“北极蓝色伙伴关系”圈、助力形成以“北极生态环境共同体”为目标的北极资源开发模式、推动中国北极法律制度建设与国际合作。 展开更多
关键词 资源-环境治理 北极命运共同体 角色定位与应因
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大庆油田石油开采对水文地质环境的影响及应因对策 被引量:16
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作者 刘大平 刘成玉 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2012年第3期136-141,共6页
矿产资源开采对水文地质环境造成了不可逆的影响,在矿业城市快速发展的过程中,高强度的城市开发建设活动同矿产资源开发造成的水文地质问题相互交织,限制了矿业城市的进一步发展,阻碍了未来的经济转型.选取我国最大的石油城市——大庆... 矿产资源开采对水文地质环境造成了不可逆的影响,在矿业城市快速发展的过程中,高强度的城市开发建设活动同矿产资源开发造成的水文地质问题相互交织,限制了矿业城市的进一步发展,阻碍了未来的经济转型.选取我国最大的石油城市——大庆作为研究石油资源开采对水文地质环境影响的典型区域,从大庆油田石油开采的现状及特点分析入手,结合石油开采对区域水文地质环境影响的机理,对大庆地区水文地质环境的演化进行了研究.利用CorelDRAWX4工作平台,模拟了大庆市1960年以来3个阶段的地下水降落漏斗的形成及模式.通过理论与实证相结合的手段,阐明了大庆油田石油开采对区域性水文地质环境演化的影响因素及影响过程,并提出了相应的应对防治措施,以改善和修复该区域水文地质环境,同时为面临相似问题的区域提供防治参考. 展开更多
关键词 石油开采 水文地质环境 大庆油田 应因对策
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知识产权国际治理晚近发展再思考与中国应对
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作者 张灿 《海峡法学》 2024年第2期94-107,共14页
晚近知识产权国际法治表现出机制转换、规则发展两大主要特点,区域经贸协定(RTA)属于WTO多边体制的合法例外,RTA中的知识产权规则实质是各成员方在知识产权国际保护议题上的特惠制安排。由于WTO多哈回合陷入僵局、全球价值链争夺等多方... 晚近知识产权国际法治表现出机制转换、规则发展两大主要特点,区域经贸协定(RTA)属于WTO多边体制的合法例外,RTA中的知识产权规则实质是各成员方在知识产权国际保护议题上的特惠制安排。由于WTO多哈回合陷入僵局、全球价值链争夺等多方因素,高水平RTA知识产权规则近年来大量涌现。RTA知识产权规则无法撼动多边知识产权规则在知识产权国际治理中的基石地位,亦无法取代其重要作用。知识产权国际治理将在区域与多边机制的相互影响和制衡中向前发展。在知识产权强国建设背景下,我国应统筹推进知识产权国内法治与涉外法治,坚持多边主义,善用区域机制,在多边层面提出更多各国关心的普遍性议题,在区域层面探索形成我国自贸协定知识产权规则范式,为知识产权国际规则创新及发展贡献更多中国智慧。 展开更多
关键词 知识产权国际治理 晚近发展 区域经贸协定 多边主义 中国应因
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Regulatory Impact Assessment of the EU Digital Market Surveillance and Chinese Response Plan
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作者 Kang Lanping 《科技与法律(中英文)》 CSSCI 2024年第6期127-137,共11页
As a data protection legislation with the dual objectives of market regulation and government supervision,the EU General Data Protection Regulation(GDPR)is designed to promote the cultivation of a market for data ele⁃... As a data protection legislation with the dual objectives of market regulation and government supervision,the EU General Data Protection Regulation(GDPR)is designed to promote the cultivation of a market for data ele⁃ments and to regulate the data processing subjects'behaviour.The civil legal norms to participate in the data market regulation are introduced,and a right-protected mode with the obligation norms of data controllers as the core is started by GDPR.However,from the perspective of GDPR's global enforcement effectiveness,as an export-orientated global standard and protection framework,the power regulation model of the EU's single digital market is facing the in⁃novative incentives of data market expansion and the tension of human rights protection.A more modest and moderate data governance regulation model has been opened by a new round of the EU digital market regulation.The legal sce⁃narios transition and digital platforms regulation more fit the regulatory demand and development goals of global digital economy development.The EU's determination to enhance the global digital market share and competitiveness is dem⁃onstrated.For China,the impact and security risks of the new round should be evaluated carefully,drawing on the ex⁃perience of the technical standpoint and institutional framework and regulatory rules of the EU digital market regula⁃tion,providing the regulatory models and Chinese solutions to respond to the EU digital market regulation,and enhanc⁃ing Chinese institutional discourse and rule-making leadership in the global digital economy. 展开更多
关键词 EU digital market regulation GDPR regulation mode legal response
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Antidepressant effects of Yuanzhi (Polygalae Radix) extract on chronic unpredictable mild stress-induced depression in rats: modulation of the NLRP3 inflammasome and NF-κB pathway
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作者 CHEN Yuzhen ZHAO Yongzhi +4 位作者 ZHANG Yiwen CHEN Fang Iqbal Choudhary Muhammad LIU Xinmin JIANG Ning 《Digital Chinese Medicine》 CAS CSCD 2024年第2期184-194,共11页
Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total ... Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total of 40 male Sprague Dawley(SD)rats were randomly divided into control;model;low dose of PR(PR-L;0.5 g/kg);high dose of PR(PR-H;1 g/kg);and fluoxetine(10 mg/kg)groups;with 8 rats in each group.Except for the rats in control group;those in the other four groups underwent CUMS-induced depression modeling.PR and fluoxetine were administered intragastrically once daily;30 min prior to the CUMS procedure;for 14 consecu-tive days until the behavioral tests were performed.After CUMS modeling;the sucrose prefer-ence test(SPT);open field test(OFT);novelty-suppressed feeding test(NSFT);forced swim test(FST);and tail suspension test(TST)were employed to assess the pharmacological ef-fects of PR on the mitigation of depressive-like behaviors in rat models.Additionally;the en-zyme-linked immunosorbent assay(ELISA)was utilized to quantify the serum levels of tumor necrosis factor(TNF)-α;interleukin(IL)-6;and IL-1βin the rats.Western blot analysis was al-so conducted to evaluate the protein expression levels of nuclear factor kappa-B(NF-κB);in-ducible nitric oxide synthase(iNOS);cyclooxygenase-2(COX-2);nucleotide-binding oligomerization domain(NOD)-like receptor family pyrin domain containing 3(NLRP3);apoptosis-associated speck-like protein containing caspase recruitment domain(ASC);and caspase-1 in the hippocampal tissues of the rats.Immunofluorescence staining was per-formed to observe the morphological changes in ionized calcium-binding adapter molecule 1 positive(Iba-1+)cells in the dentate gyrus(DG)of rats with CUMS-induced depression.Results(i)Treatment with PR-H and fluoxetine resulted in significant enhancements in both the total distance and time the rats moved during tests(P<0.01 and P<0.05;respectively).Post-administration of PR-H and fluoxetine also led to statistically significant increase in su-crose preference among rats(P<0.05).Besides;PR-L;PR-H;and fluoxetine treatment markedly decreased the latency of ingestion(P<0.05;P<0.05;and P<0.01;respectively).As observed from the FST;PR-L;PR-H;and fluoxetine presented antidepressant effects on rats with CUMS-induced depression;leading to the reduction in time of their immobility(P<0.05;P<0.01;and P<0.01;respectively).The results of TST indicated reduced immobility time in rats receiving PR-H and fluoxetine treatment as well(P<0.01).(ii)Rats in model group showed an increase in the levels of Iba-1+microglia in their left and right brains in compari-son with control group(P<0.01).However;such increase was negated post PR treatment(P<0.01).Treatment with PR-L;PR-H;and fluoxetine considerably reduced the levels of inflam-matory factors(TNF-α;IL-1β;and IL-6;P<0.01).In addition;treatment of PR-L and PR-H ef-fectively counteracted the elevated levels of NLRP3;ASC;and caspase-1;and markedly down-regulated the expression levels of phosphorylated p65(p-p65);COX-2;and iNOS in rats’hip-pocampus(P<0.01).Conclusion Collectively;these findings indicate that PR exerts an antidepressant effect on rats with CUMS-induced depression partially through the modulation of the NLRP3 and NF-κB signaling pathways. 展开更多
关键词 DEPRESSION Yuanzhi(Polygalae Radix) Chronic unpredictable mild stress(CUMS) Proinflammatory cytokine Neuroinflammatory
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危机与应对——黄崖教案后的李光炘与太谷学派 被引量:1
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作者 张进 《扬州大学学报(人文社会科学版)》 北大核心 2010年第3期87-92,共6页
黄崖教案后,太谷学派面临重大危机。作为太谷学派的南宗领袖,李光炘通过强化与地方社会力量的联系,努力改善与上层社会的关系,构建全新的社会支持网络。李光炘通过约束个人的言行举止,规范学派内部的组织活动,不断加强和彰显其学术属性... 黄崖教案后,太谷学派面临重大危机。作为太谷学派的南宗领袖,李光炘通过强化与地方社会力量的联系,努力改善与上层社会的关系,构建全新的社会支持网络。李光炘通过约束个人的言行举止,规范学派内部的组织活动,不断加强和彰显其学术属性,淡化其宗教神秘色彩,使太谷学派的社会生态系统得到明显改善。李光炘主动采取一系列的因应举措,使得太谷学派继续得到发展并发扬光大。 展开更多
关键词 太谷学派 危机 应因 黄崖教案 李光炘
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Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect
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作者 HOU Ming-xiao HUANG Bing-xiang +2 位作者 ZHAO Xing-long JIAO Xue-jie ZHENG Chen-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2446-2466,共21页
Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way t... Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way to control the hard limestone roof.In this study,the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed.The results show that the acid with stronger hydrogen production capacity after ionization(pK_(a)<0)has more prominent damage to the mineral grains of limestone.When pKa increases from−8.00 to 15.70,uniaxial compressive strength and elastic modulus of limestone increase by 117.22%and 75.98%.The influence of acid concentration is manifested in the dissolution behavior of mineral crystals,the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength,and the strength after 15%concentration reformation can be reduced by 59.42%.The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage(within 60 min).The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system.Based on the analytic hierarchy process method,the influence weights of acid type,acid concentration and acidification time on strength are 24.30%,59.54% and 16.16%,respectively.The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines. 展开更多
关键词 hard roof acidic effect structural reformation strength weakening influencing factors
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高等教育国际化因应方略 被引量:1
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作者 彭森明 《集美大学学报(教育科学版)》 2003年第4期19-22,共4页
从高等教育现代化的视野出发,讨论了高等教育国际化的应因对策,提出高等教育国际化要固本,要着眼本国的教育品质,提升大学的学术水准,宜采取积极主动的方式等观点。
关键词 高等教育 国际化 应因方略
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Anti-Plane Elasticity Problem and Mode Ⅲ Crack Problem of Cubic Quasicrystal 被引量:3
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作者 周旺民 范天佑 +1 位作者 尹姝媛 王念鹏 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期250-254,共5页
The fracture theory of cubic quasicrystal was developed. The exact analytic solution of a Mode Ⅲ Griffith crack in the material was obtained by using the Fourier transform and dual integral equations theory, and so t... The fracture theory of cubic quasicrystal was developed. The exact analytic solution of a Mode Ⅲ Griffith crack in the material was obtained by using the Fourier transform and dual integral equations theory, and so the displacement and stress fields, the stress intensity factor and strain energy release rate were determined. The results show that the stress intensity factor is independent of material constants, and the strain energy release rate is dependent on all material constants. These provide important information for studying the deformation and fracture of the new solid material. 展开更多
关键词 anti plane elasticity problem Mode crack cubic quasicrystal stress intensity factor strain energy release rate
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Analysis of Climatic Factors Causing Yield Difference in Ramie among Different Eco-regions of Yangtze Valley 被引量:3
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作者 刘头明 汤清明 +1 位作者 朱四元 唐守伟 《Agricultural Science & Technology》 CAS 2011年第5期745-750,共6页
[Objective] This study was to investigate the climatic factors affecting the regional eco-adaptability of ramie.[Method] Five experimental sites of different eco-types in ramie growing regions in Yangtze Valley were s... [Objective] This study was to investigate the climatic factors affecting the regional eco-adaptability of ramie.[Method] Five experimental sites of different eco-types in ramie growing regions in Yangtze Valley were set up to investigate the yield of Zhongzhu No.2,based on which we assessed the adaptability of Zhongzhu No.2 to various eco-regions and further analyzed the climatic factors causing the difference in eco-adaptability.[Result] Ramie yield varied largely among various experimental sites and the yield difference appeared to be well repeatable,with a differential value between the maximum and the minimum reaching 2.3 kg/20 m2.Analysis of the yield data,together with climatic factors in various ecological regions showed that yield of Zhongzhu No.2 was significantly correlated with rainfall,sunshine hours,relative humidity during its growing period.Of the climatic factors,sunshine hours and rainfall can positively promote yield increase,while relative humidity negatively regulate ramie yield.[Conclusion] The climatic indices,including rainfall,sunshine duration and relative humidity are a key factor causing yield difference in ramie among different regions of Yangtze Valley. 展开更多
关键词 RAMIE Eco-adaptability Climatic factor
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Isolation and Structural Analysis of DRE-Binding Transcription Factor from Maize (Zea mays L.) 被引量:11
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作者 秦峰 李洁 +3 位作者 张贵友 赵军 陈受宜 刘强 《Acta Botanica Sinica》 CSCD 2003年第3期331-339,共9页
Dehydration-responsive element-binding (DREB) proteins specifically binding with dehydration-responsive element (DRE) have been identified as a kind of important transcription activator of plants under drought, high s... Dehydration-responsive element-binding (DREB) proteins specifically binding with dehydration-responsive element (DRE) have been identified as a kind of important transcription activator of plants under drought, high salt and cold stress. The conserved amino, acid residues of Val (14th residue) and Glu (19th residue) in AP2/EREBP domain of DREB1A have been identified to be two key points in determining the binding ability of DREB gene with DRE element. Using the yeast one-hybrid system, we isolated one maize DREB gene named maDREB1 by screening cDNA library. Trans-activation experiment in yeast reporter strain demonstrated that maDREB1 protein could function as a DREB transcription factor activating target gene expression by specifically binding to the DRE cis-element. To assess the functional significance of these two residues in maDREB1, the V14 and E19 were substituted individually or doubly by Ala and Asp. Point mutation analysis showed that V14 substitution made significant loss of binding ability with DRE element, while point mutation of E19 had less effect. If the substitution happened simultaneously to these two residues, it would lead to great loss of the ability of binding with DRE element. It suggested that V14 and E19 were both important in protein-DNA interacting in maDREB1, though 14V was more essential. The copy number and expression pattern of maDREB1 was discussed. 展开更多
关键词 maDREB1 transcription factor dehydration-responsive element (DRE)
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Molecular Tagging and Effect Analysis of a New Small Grain Dwarf Gene in Rice 被引量:4
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作者 李秀兰 吴成 +3 位作者 邓晓建 王平荣 李仁端 杨志荣 《Acta Botanica Sinica》 CSCD 2003年第7期757-761,共5页
Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lod... Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizer. Dwarf breeding had made a great breakthrough in the rice breeding. The breeding and extension of excellent dwarf varieties remarkably improved the yield potential of rice. Therefore, the plant height is still one of the focuses in rice genetic research. 展开更多
关键词 Oryza sativa dwarf gene gene mapping microsatellite marker gene effect analysis
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Thermal-hydro-mechanical coupling stress intensity factor of brittle rock 被引量:3
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作者 李鹏 饶秋华 +1 位作者 李卓 敬静 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期499-508,共10页
A new calculation formula of THM coupling stress intensity factor was derived by the boundary collocation method, in which an additional constant stress function was successfully introduced for the cracked specimen wi... A new calculation formula of THM coupling stress intensity factor was derived by the boundary collocation method, in which an additional constant stress function was successfully introduced for the cracked specimen with hydraulic pressure applied on its crack surface. Based on the newly derived formula, THM coupling fracture modes (including tensile, shear and mixed fracture mode) can be predicted by a new fracture criterion of stress intensity factor ratio, where the maximum axial load was measured by self-designed THM coupling fracture test. SEM analyses of THM coupling fractured surface indicate that the higher the temperature and hydraulic pressure are and the lower the confining pressure is, the more easily the intergranular (tension) fracture occurs. The transgranular (shear) fracture occurs in the opposite case while the mixed-mode fracture occurs in the middle case. The tested THM coupling fracture mechanisms are in good agreement with the predicted THM coupling fracture modes, which can verify correction of the newly-derived THM coupling stress intensity factor formula. 展开更多
关键词 stress intensity factor thermal-hydro-mechanical coupling boundary collocation method fracture mechanism brittle rock
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Isolation, Expression Characteristics and Chromosomal Locations of Three cDNA Fragments Under Salt Stress in Rice 被引量:3
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作者 钱前 柳原城司 +3 位作者 滕胜 曾大力 朱立煌 陈受宜 《Acta Botanica Sinica》 CSCD 2003年第9期1090-1095,共6页
cDNA libraries were constructed from the leaves of a rice (Oryza sativa L.) salt tolerancevariety Tesan抋i 2 growing in solutions with 150 mmol/L NaCl for 3 h or without salt stress. Three salt-responsive cDNA clones,... cDNA libraries were constructed from the leaves of a rice (Oryza sativa L.) salt tolerancevariety Tesan抋i 2 growing in solutions with 150 mmol/L NaCl for 3 h or without salt stress. Three salt-responsive cDNA clones, Ts1, Ts2 and Ts3 were isolated by differential screening. Northern blottinganalysis showed that the transcription levels of Ts1 and Ts2 increased within 3 h salt stress and kept onincreasing within 24 h, while the transcription level of Ts3 reached its peak within 3 h. Sequence analysisindicated that there were no homologies between the three cDNA clones and any known gene. The threecDNA clones were mapped using a doubled haploid (DH) population derived from an indica variety ZYQ8,which was a salt tolerance parent of Tesan抋i 2, with a japonica variety JX17. Ts1, Ts2 and Ts3 werelocated on chromosomes 1, 3 and 7, respectively. It was noted that Ts1, Ts2, and Ts3 were in or near theregions of major or minor salt tolerance quantitative trait loci (QTLs), which were mapped in the same DHpopulation in a parallel study. 展开更多
关键词 RICE differential screening salt stress response mappingAbstract: cDNA libraries were constructed from the leaves of a rice (Oryza sativa L.) salttolerance variety Tesan’ai 2 growing in solutions with 150 mmol/L NaCl for 3 h or without s
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Experimental study on dynamic fracture behavior of three-point bending beam with double deformity inclusions 被引量:2
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作者 岳中文 宋耀 +2 位作者 韩瑞杰 张旺 郭超 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期333-338,共6页
The dynamic fracture behavior of the three-point bending beam with double deformity inclusions under impact loading is studied by using digital high-speed photography in combination with the transmission-type dynamic ... The dynamic fracture behavior of the three-point bending beam with double deformity inclusions under impact loading is studied by using digital high-speed photography in combination with the transmission-type dynamic caustic method. The experimental results indicate that the fluctuation of crack propagation velocity v first increases and then decreases in the crack propagation process. During the process of crack propagating into the inclusion area, the fracture resistance effect of the circular inclusion is the most significant and the effects of triangular and square inclusions are less obvious. The stress intensity factor near the crack tip increases during the propagation process and reaches its maximum value when the crack tip is close to the inclusions. The crack tip’s dynamic stress intensity factor ( DSIF) decreases when the crack exceeds the middle area of the double inclusions. These results provide an experimental basis and scientific foundation to strengthen the evaluation and fracture analysis of the structure containing deformity inclusions. 展开更多
关键词 dynamic caustics deformity inclusion dynamic stress intensity factor crack propagation velocity
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Dynamic caustics experimental study on interaction between propagating crack and deformity inclusions in primary structure 被引量:2
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作者 岳中文 韩瑞杰 +1 位作者 张旺 刘伟 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期73-77,共5页
The approach combining the dynamic caustics method with high-speed photography technology is used to study the interaction between propagating cracks and three kinds of deformity inclusions( cylinder inclusion, quadr... The approach combining the dynamic caustics method with high-speed photography technology is used to study the interaction between propagating cracks and three kinds of deformity inclusions( cylinder inclusion, quadruple inclusion and triangular inclusion) under lowvelocity impact loading. By recording the caustic spots of crack tips at different moments during the crack propagation, the variation regulations of dynamic stress intensity factors( DSIF) and crack growth velocity with respect to time are obtained. The experimental results showthat the resistance effects to crack growth are varied with different shapes of inclusions in specimens, and the quadruple inclusion's effect is more apparent. The distortion degree of caustic spots is affected by the shapes of inclusions as well, and the situation is more serious for cylinder and quadruple inclusions. The overall values of DSIFs of triangular inclusion specimen are greater than the others, and the crack growth velocities, characteristic sizes and DSIFs showprocesses of fluctuations because of the disturbance of reflection waves in specimens. The results provide an experimental basis for the analysis of strength and impact-resistance ability in structures with deformity inclusions. 展开更多
关键词 dynamic caustics deformity inclusion dynamic stress intensity factor(DSIF) crack propagation velocity
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High Altitude Adaptation and Phylogenetic Analysis of Tibetan Horse Based on the Mitochondrial Genome 被引量:9
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作者 徐树青 洛桑江白 +7 位作者 华桑 何健 阿叁次仁 王威 童晓梅 梁羽 汪建 郑晓光 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期720-729,共10页
To investigate genetic mechanisms of high altitude adaptations of animals living in the Tibetan Plateau, three mitochondrial genomes (mt-genome) of Tibetan horses living in Naqu (4,500 m) of Tibetan, Zhongdian (3... To investigate genetic mechanisms of high altitude adaptations of animals living in the Tibetan Plateau, three mitochondrial genomes (mt-genome) of Tibetan horses living in Naqu (4,500 m) of Tibetan, Zhongdian (3,300 m) and Deqin (3,100 m) of Yunnan province were sequenced. The structures and lengths of these three mt-genomes are similar to the Cheju horse, which is related to Tibetan horses, but little shorter than the Swedish horse. The pair-wise identity of these three horses on nucleotide level is more than 99.3%. When the gene encoding the mitochondrial protein of Tibetan horses was analyzed, we found that NADH6 has higher non-synonymous mutation rate in all of three Tibetan horses. This implies that NADH6 may play a role in Tibetan horses' high altitude adaptation. NADH6 is one of the subunits of the complex I in the respiratory chain. Furthermore, 7 D-loop sequences of Tibetan horse from different areas were sequenced, and the phylogeny tree was constructed to study the origin and evolutionary history of Tibetan horses. The result showed that the genetic diverse was high among Tibetan horses. All of Tibetan horses from Naqu were clustered into one clade, and Tibetan horses from Zhongdian and Deqin were clustered into others clades. The first molecular evidence of Tibetan horses indicated in this study is that Tibetan horse population might have multiple origins. 展开更多
关键词 Tibetan horses mitochondrial genome high altitude adaptation NADH6 PHYLOGENY
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River channel flood forecasting method of coupling wavelet neural network with autoregressive model 被引量:1
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作者 李致家 周轶 马振坤 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期90-94,共5页
Based on analyzing the limitations of the commonly used back-propagation neural network (BPNN), a wavelet neural network (WNN) is adopted as the nonlinear river channel flood forecasting method replacing the BPNN.... Based on analyzing the limitations of the commonly used back-propagation neural network (BPNN), a wavelet neural network (WNN) is adopted as the nonlinear river channel flood forecasting method replacing the BPNN. The WNN has the characteristics of fast convergence and improved capability of nonlinear approximation. For the purpose of adapting the timevarying characteristics of flood routing, the WNN is coupled with an AR real-time correction model. The AR model is utilized to calculate the forecast error. The coefficients of the AR real-time correction model are dynamically updated by an adaptive fading factor recursive least square(RLS) method. The application of the flood forecasting method in the cross section of Xijiang River at Gaoyao shows its effectiveness. 展开更多
关键词 river channel flood forecasting wavel'et neural network autoregressive model recursive least square( RLS) adaptive fading factor
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A Novel Cotton Gene Encoding a New Class of Chitinase 被引量:5
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作者 李骥 刘进元 《Acta Botanica Sinica》 CSCD 2003年第12期1489-1496,共8页
DA novel chitinase gene (GhChia7) was isolated from salicylic acid (SA)-treated cotton cotyledons and characterized by DNA sequence analysis of its cDNA and genomic DNA clone. The deduced amino acid sequence, designat... DA novel chitinase gene (GhChia7) was isolated from salicylic acid (SA)-treated cotton cotyledons and characterized by DNA sequence analysis of its cDNA and genomic DNA clone. The deduced amino acid sequence, designated as class VII chitinase, shares about 30% identity to class I or II chitinases, and does not correspond to any of the previously characterized classes I-VI chitinases. Northern blotting analysis showed that the transcripts of GhChia7 were abundant both in cotton fibers and in the roots of the seedlings. The accumulation of GhChia7 mRNA in SA-treated cotyledons reached maximum at 7.5 mmol/ L concentration after 18 h. Results indicate that GhChia7 might play an important role in cotton's active defense response. 展开更多
关键词 Gossypium hirsutum chitinase gene salicylic acid cotton defense
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New Formulation for Arbitrary Cracks Problem and Its Stress Intensity Factor of Plane Elasticity 被引量:4
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作者 杨晓春 范天佑 刘士强 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期364-369,共6页
Aim The general arbitrary cracked problem in an elastic plane was discussed. Methods For the purpose of acquiring the solution of the problem, a new formulation on the problem was proposed. Compared with the classic... Aim The general arbitrary cracked problem in an elastic plane was discussed. Methods For the purpose of acquiring the solution of the problem, a new formulation on the problem was proposed. Compared with the classical plane elastic crack model, only the known conditions were revised in the new formulation, which are greatly convenient to solve the problem, and no other new condition was given. Results and Conclusion The general exact analytic solution is given here based on the formulation though the problem is very complicated. Furthermore, the stress intensity factors K Ⅰ, K Ⅱ of the problem are also given. 展开更多
关键词 complex variable function method general curve cracks Riemann Hilbert boundary value problem closed form solution stress intensity factors
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