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“因应”与“吸引”——明末清初西方在华传教士的传教策略 被引量:1
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作者 李建明 《船山学刊》 2005年第3期119-121,共3页
明末清初,以利玛窦为代表的西方来华传教士为传教,采取“因应”和“吸引”策略,心理上最大限度消除了中国人长久以来形成的对西方的鄙视;言行上最大限度地减少了对西方传教士传播基督教义的抵制;客观上推动了中国科学技术的进步,促进了... 明末清初,以利玛窦为代表的西方来华传教士为传教,采取“因应”和“吸引”策略,心理上最大限度消除了中国人长久以来形成的对西方的鄙视;言行上最大限度地减少了对西方传教士传播基督教义的抵制;客观上推动了中国科学技术的进步,促进了中西文化的交流。 展开更多
关键词 明末清初 西方在华传教士 传教策略 文化交流 基督教 “因应” “吸引”
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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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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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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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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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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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Design,Analysis,and Optimization of a CMOS Active Pixel Sensor 被引量:2
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作者 徐江涛 姚素英 +2 位作者 李斌桥 史再峰 高静 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第9期1548-1551,共4页
A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and succ... A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and success-fully taped out with a Chartered 0.35μm process. The pixel pitch is 8μm × 8μm with a fill factor of 57%, the photo-sensitivity is 0.8V/(lux · s) ,and the dynamic range is 50dB. Theoretical analysis and test results indicate that as the process is scaled down, a smaller pixel pitch reduces the sensitivity. A deep junction n-well/p-substrate photodiode with a reasonable fill factor and high sensitivity are more appropriate for submicron processes. 展开更多
关键词 CMOS image sensor active pixel sensor fill factor photo-response sensitivity
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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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Performance Analysis of RF Spiral Inductor with Gradually Changed Metal Width and Space 被引量:2
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作者 王勇 石艳玲 +5 位作者 刘斌贝 丁艳芳 唐深群 朱骏 陈寿面 赵宇航 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1716-1721,共6页
To decrease the metal losses of RF spiral inductor,a novel layout structure with gradually reduced metal line width and space from outside to inside is presented. This gradual changed inductor has less eddy-current ef... To decrease the metal losses of RF spiral inductor,a novel layout structure with gradually reduced metal line width and space from outside to inside is presented. This gradual changed inductor has less eddy-current effect than the conventional inductor of fixed metal width and space. So the series resistance can be reduced and the quality (Q) factor of the inductor relating to metal losses is increased. The obtained experimental results corroborate the validity of the proposed method. For a 6nH inductor on high-resistivity silicon at 2.46GHz,Q factor of 14.25 is 11.3% higher than the conventional inductor with the same layout size. This inductor can be integrated with radio frequency integrated circuits to gain better performance in RF front end of a wireless communication system. 展开更多
关键词 RF spiral inductor quality factor eddy-current effect metal losses
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STUDY ON CRACKED PLATES WITH BONDED PATCHES UNDER IN PLANE BIAXIAL LOADINGS
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作者 徐建新 魏志毅 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期141-147,共7页
Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensi... Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensity factor (SIF) at the crack tip, the maximum tensile stress in the composite patch and the maximum shear stress in the adhesive bond between the patch and the plate. Without the patch, a tensile or compressive stress parallel to the crack has no effect on the SIF at the crack tip. While with a composite patch, there exists coupling effect between the normal stress parallel to the crack and the SIF, and the coupling effect depends significantly on ply orientation of the patch and the biaxial stress ratio of the plate. 展开更多
关键词 composite patch CRACK stress intensity factor stress ratio
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Advances in the Regulation of RpoS Protein Expression and Its Function in Bacteria 被引量:2
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作者 王淑娴 李天保 +4 位作者 叶海斌 魏鉴腾 王勇强 刁菁 杨秀生 《Agricultural Science & Technology》 CAS 2012年第6期1215-1221,1225,共8页
RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulat... RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulated at three levels: transcription level, translation level and post-translational level. Environmental stress enters bacterial cells through signal transduction and leads to a series of variations in microenvironment, thereby causing changes of regulator and controlling its levels based on the direct and indirect interaction between regulator and RpoS protein. In addition, RpoS protein has played special roles in bacteria, therefore the changes of RpoS protein levels will lead to variations in expression levels of a large number of genes, thereby causing variations of bacterial response to different environmental stress and changes of certain characteristics of bacteria, which provides a new strategy for the control of bacterial diseases in the future. This paper reviewed the recent progress on the regulation of RpoS protein expression and its function in several common bacteria. Due to the functional complexity of RpoS protein, there are still a lot of unknown functions to be further identified. 展开更多
关键词 RpoS or σ S rpoS gene Expression regulation Environmental stress RpoS function
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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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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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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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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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Research on Visualization of Long-staple Cotton Growth in Southern Xinjiang
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作者 司春景 席亚军 《Agricultural Science & Technology》 CAS 2011年第11期1738-1740,共3页
Base on the related researches at home and abroad, using systematic analysis principle mathematical modeling techniques, analysis model of organ collection properties, root structure model, mechanism model of spatial ... Base on the related researches at home and abroad, using systematic analysis principle mathematical modeling techniques, analysis model of organ collection properties, root structure model, mechanism model of spatial form of organs and dynamic model of plant topological structure in line with the growth of long-staple cotton are constructed, and three-dimensional dynamic simulation of long-staple cotton in southern Xinjiang is finally achieved. The system can promote people's understanding and perception on growth process of long-staple cotton in southern Xinjiang, which provides support for analysis of relationship between structure and function of long-staple cotton, design of ideal plant and regulation of growth model. 展开更多
关键词 Virtual growth VISUALIZATION FACTORS Topological structure
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Caustics study of the effect of glass fibres on dynamic fracture of hardened cement paste 被引量:1
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作者 杨立云 杨仁树 +1 位作者 赵雪楠 方士正 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期475-479,共5页
The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabric... The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabricated and the reflective coating on the surface of the specimen was prepared. Secondly the crack path and the shadow spot patterns during the crack propagation process for the two specimens were recorded by using a multi-spark high speed camera.Thirdly some dynamic parameters of two cement paste specimens including crack onset time the dynamic stress intensity factor and crack growth velocity were determined and analyzed comparatively.This indicates that the glass fibres can improve the fracture resistance and delay fracture time.These results will play an important role in evaluating the dynamic fracture properties of cement paste. 展开更多
关键词 reflected optical caustics cement paste glass FIBRE dynamic fracture dynamic stress intensity factor reflected optical caustics cement paste glass FIBRE dynamic fracture dynamic stress intensity factor
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Chloroplast Genetic Engineering in Higher Plants 被引量:1
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作者 张景昱 张嫄 宋艳茹 《Acta Botanica Sinica》 CSCD 2003年第5期509-516,共8页
Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plasti... Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plastid genome, engineering plant metabolic system, generating transplastomic plants with higher resistance to insect, disease, drought and herbicide and bioproducing of antibodies and vaccines. In this review, the principle and operating system for chloroplast genetic engineering and its application in higher plants have been discussed. 展开更多
关键词 chloroplast genetic engineering transplastomic plants plastid genome
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