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基于模糊理论的滚子活齿行星传动可靠性优化设计
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作者 彭程 《企业技术开发》 2006年第8期24-26,共3页
文章利用模糊可靠性优化设计方法,综合考虑了滚子活齿行星传动中有关设计参数、约束条件的随机性和模糊性,建立了基于模糊可靠性分析的以材料最省为目标的优化设计模型,并进行了实例计算和结果分析。
关键词 模糊可靠性 优化设计 齿传动 啮合
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滚子活齿行星传动的模糊可靠性优化设计
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作者 骆行 《机械设计与制造》 2004年第5期7-8,共2页
滚子活齿行星传动是一种新型的传动方式,它由K-H-V型少齿差行星传动演化而成。由于其传动过程中的特点,使用传统的常规设计方法往往不能够得到理想的设计效果,这里引入模糊可靠性优化设计方法,使得这一问题得到了较好的解决,并给出了应... 滚子活齿行星传动是一种新型的传动方式,它由K-H-V型少齿差行星传动演化而成。由于其传动过程中的特点,使用传统的常规设计方法往往不能够得到理想的设计效果,这里引入模糊可靠性优化设计方法,使得这一问题得到了较好的解决,并给出了应用实例。 展开更多
关键词 模糊可靠性 齿传动 啮合 摆线
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滚子活齿行星传动的齿廓曲线方程
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作者 叶松年 《水利电力机械》 1994年第6期17-22,共6页
介绍了滚子活齿行星传动的形式及啮合原理,推出了内啮合及外啮合的齿廓曲线方程。
关键词 齿 齿廓 曲线方程 行星齿轮
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玻璃原板上活淋子的原因分析
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作者 柳如宽 王立新 包树勇 《玻璃》 1999年第1期37-38,共2页
活淋子在有槽垂直引上法生产平板玻璃中有时能够见到,如作业温度出现大的波动,原料有成分(特别是硅质原料)发生大的变化时极易产生活淋子。本文对硅质原料——石英砂颗粒度超标所产生活淋子的现象加以分析。
关键词 石英砂 颗粒度 玻璃 缺陷
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滚子活齿行星传动啮合廓曲线方程
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作者 叶松年 《水利电力机械电子技术》 1990年第4期1-9,共9页
关键词 齿 行星传动 啮合齿廓曲线 方程
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强肾活血孕子汤治疗卵巢储备功能下降所致高龄不孕49例
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作者 胡程 《浙江中医杂志》 2021年第12期903-903,共1页
笔者采用强肾活血孕子汤治疗卵巢储备功能下降(DOR)高龄不孕妇女,探讨其对患者性激素水平及妊娠的影响,为DOR不孕症的治疗提供新的思路。1一般资料将98例肾虚血瘀型DOR高龄不孕妇女纳为本研究的观察对象,病例收集时间为2019年1月至2020... 笔者采用强肾活血孕子汤治疗卵巢储备功能下降(DOR)高龄不孕妇女,探讨其对患者性激素水平及妊娠的影响,为DOR不孕症的治疗提供新的思路。1一般资料将98例肾虚血瘀型DOR高龄不孕妇女纳为本研究的观察对象,病例收集时间为2019年1月至2020年12月。遵循随机数字表法的原则将其分为两组:观察组和对照组,每组49例患者。 展开更多
关键词 强肾血孕 卵巢储备功能下降 不孕症 临床观察
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约氏疟原虫合子的分离和动合子培养
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作者 郝宏兴 苟俊 +1 位作者 张静茹 段建华 《第三军医大学学报》 CAS CSCD 北大核心 2001年第12期1486-1488,共3页
目的 从感染小鼠血液直接分离约氏疟原虫合子 ,并在体外培养 ,转化为动合子。方法 体外诱导感染鼠血中的约氏疟原虫雌雄配子形成、受精 ,采用Ficoll 40 0 Hypaque密度梯度离心法分离合子 ,并在MEM培养基中培养。结果 从 1 0~ 1 5... 目的 从感染小鼠血液直接分离约氏疟原虫合子 ,并在体外培养 ,转化为动合子。方法 体外诱导感染鼠血中的约氏疟原虫雌雄配子形成、受精 ,采用Ficoll 40 0 Hypaque密度梯度离心法分离合子 ,并在MEM培养基中培养。结果 从 1 0~ 1 5只感染小鼠血液可分离到 1 0 6 数量级的约氏疟原虫合子 ;在 2 2℃条件下 ,经 1 8~ 2 4h培养有动合子形成。结论 可以直接从感染血中分离到约氏疟原虫合子 ,所得合子经培养可形成动合子。 展开更多
关键词 约氏疟原虫 分离 活子培养
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宫颈癌组织长链非编码RNA XIST、小分子RNA miR-101-3p表达变化及其意义 被引量:8
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作者 刘丽丹 黄浩梁 《山东医药》 CAS 北大核心 2017年第35期44-46,共3页
目的观察宫颈癌组织长链非编码RNA(LncRNA)X染色体失活特异转录子(XIST)、小分子RNA miR-101-3p表达变化,并探讨其临床意义。方法选取91例宫颈癌患者的宫颈癌组织标本为观察组,癌旁正常组织(距离宫颈癌组织>5cm且经病例检查证实为正... 目的观察宫颈癌组织长链非编码RNA(LncRNA)X染色体失活特异转录子(XIST)、小分子RNA miR-101-3p表达变化,并探讨其临床意义。方法选取91例宫颈癌患者的宫颈癌组织标本为观察组,癌旁正常组织(距离宫颈癌组织>5cm且经病例检查证实为正常组织)标本为对照组。采用实时荧光定量PCR法检测两组标本中的XIST、miR-101-3p表达,并分析其与宫颈癌临床病理参数的关系。结果观察组、对照组XIST表达量分别为8.97±3.56、7.01±3.82,miR-101-3p表达量分别为8.24±4.22、10.15±3.97。观察组XIST表达量高于对照组(P<0.05),miR-101-3p表达量低于对照组(P<0.05)。Pearson积矩相关分析结果显示宫颈癌组织miR-101-3p、XIST表达量呈负相关性(r=-0.716,P<0.05)。肿瘤最大径≥4 cm、FIGO分期Ⅲ+Ⅳ期、低分化、有淋巴结转移的宫颈癌组织中miR-101-3p表达量分别低于于肿瘤最大径<4 cm、FIGO分期Ⅰ+Ⅱ期、中高分化、无淋巴结转移的宫颈癌组织(P均<0.05),XIST表达量分别高于于肿瘤最大径<4 cm、FIGO分期Ⅰ+Ⅱ期、中高分化、无淋巴结转移宫颈癌组织(P均<0.05)。结论宫颈癌组织XIST表达升高、miR-101-3p表达降低。检测宫颈组织XIST、miR-101-3p有助于宫颈癌的病情判断。 展开更多
关键词 宫颈癌 长链非编码RNA X染色体失特异转录 小分RNA miR-101-3p
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Integrative analysis of bone-formation associated genes and immune cell infiltration in osteoporosis, and the prediction of active ingredients in targeted traditional Chinese medicine
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作者 WANG Kai DONG Ping GUO Hongzhang 《Digital Chinese Medicine》 CAS CSCD 2024年第2期160-170,共11页
Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of ... Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of targeted traditional Chinese medicine(TCM)herbs.Methods The Gene Expression Omnibus(GEO)and GeneCards databases were employed to conduct a comprehensive screening of genes and disease-associated loci pertinent to the pathogenesis of OP.The R package was utilized as the analytical tool for the identification of differentially expressed genes.Least absolute shrinkage and selection operator(LASSO)logis-tic regression analysis and support vector machine-recursive feature elimination(SVM-RFE)algorithm were employed in defining the genetic signature specific to OP.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses for the selected pivotal genes were conducted.The cell-type identification by estimating rela-tive subsets of RNA transcripts(CIBERSORT)algorithm was leveraged to examine the infiltra-tion patterns of immune cells;with Spearman’s rank correlation analysis utilized to assess the relationship between the expression levels of the genes and the presence of immune cells.Coremine Medical Database was used to screen out potential TCM herbs for the treatment of OP.Comparative Toxicogenomics Database(CTD)was employed for forecasting the TCM ac-tive ingredients targeting the key genes.AutoDock Vina 1.2.2 and GROMACS 2020 softwares were employed to conclude analysis results;facilitating the exploration of binding affinity and conformational dynamics between the TCM active ingredients and their biological targets.Results Ten genes were identified by intersecting the results from the GEO and GeneCards databases.Through the application of LASSO regression and SVM-RFE algorithm;four piv-otal genes were selected:coat protein(CP);kallikrein 3(KLK3);polymeraseγ(POLG);and transient receptor potential vanilloid 4(TRPV4).GO and KEGG pathway enrichment analy-ses revealed that these trait genes were predominantly engaged in the regulation of defense response activation;maintenance of cellular metal ion balance;and the production of chemokine ligand 5.These genes were notably associated with signaling pathways such as ferroptosis;porphyrin metabolism;and base excision repair.Immune infiltration analysis showed that key genes were highly correlated with immune cells.Macrophage M0;M1;M2;and resting dendritic cell were significantly different between groups;and there were signifi-cant differences between different groups(P<0.05).The interaction counts of resveratrol;curcumin;and quercetin with KLK3 were 7;3;and 2;respectively.It shows that the interac-tions of resveratrol;curcumin;and quercetin with KLK3 were substantial.Molecular docking and molecular dynamics simulations further confirmed the robust binding affinity of these bioactive compounds to the target genes.Conclusion Pivotal genes including CP;KLK3;POLG;and TRPV4;exhibited commendable significant prognostic value;and played a crucial role in the diagnostic assessment of OP.Resveratrol;curcumin;and quercetin;natural compounds found in TCM;showed promise in their potential to effectively modulate the bone-forming gene KLK3.This study provides a sci-entific basis for the interpretation of the pathogenesis of OP and the development of clinical drugs. 展开更多
关键词 OSTEOPOROSIS Bone formation Differentially expressed genes Biological information Traditional Chinese medicine(TCM) Active ingredients Molecular mechanism
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Ab initio molecular dynamics simulation reveals the influence of entropy effect on Co@BEA zeolite-catalyzed dehydrogenation of ethane
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作者 Yumeng Fo Shaojia Song +8 位作者 Kun Yang Xiangyang Ji Luyuan Yang Liusai Huang Xinyu Chen Xueqiu Wu Jian Liu Zhen Zhao Weiyu Song 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期195-205,共11页
The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulati... The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures.AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased.Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction.The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3d orbital energy levels.We provided explanations consistent with the principles of thermodynamics and statistical physics.The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments. 展开更多
关键词 Ethane dehydrogenation C-H bond activation Ab initio molecular dynamics simulation ENTROPY Heterogeneous catalysis
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STAT5信号转导通路及其靶基因产物与结直肠癌恶性潜能的关系 被引量:1
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作者 欧云菘 马向涛 余力伟 《世界华人消化杂志》 CAS 北大核心 2007年第11期1306-1309,共4页
目的:分析STAT5及其靶基因产物Cyclin D1与Caspase-3在结直肠癌组织中的表达情况,探讨STAT5及其靶基因产物在结直肠癌发病机制中的作用.方法:收集北京海淀医院外科2003-12/ 2005-12经手术切除的结直肠癌标本60例,应用Western blot检测6... 目的:分析STAT5及其靶基因产物Cyclin D1与Caspase-3在结直肠癌组织中的表达情况,探讨STAT5及其靶基因产物在结直肠癌发病机制中的作用.方法:收集北京海淀医院外科2003-12/ 2005-12经手术切除的结直肠癌标本60例,应用Western blot检测60例结直肠癌组织、正常黏膜中STAT5及其靶基因产物Cyclin D1与Caspase-3表达.结果:p-STAT5,Cyclin D1及Caspase-3表达水平在结直肠癌组织中明显高于正常黏膜(P= 0.028,0.035,0.046);p-STAT5表达水平与分期相关(P=0.026);Caspase-3与分期相关(P= 0.041).p-STAT5与Caspase-3在结直肠癌组织中表达情况呈线性相关(r=0.412,P<0.05).结论:STAT5信号转导通路可能在结直肠癌发生过程中起重要作用,检测结直肠癌中STAT5及其靶基因产物的表达可以反映肿瘤的恶性潜能. 展开更多
关键词 结直肠癌 信号转导 转录信号转导与激 活子 CYCLIN D1 Caspase-3 Western BLOT
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Continuous changes in electrical conductivity of sodium aluminate solution in seeded precipitation 被引量:3
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作者 刘桂华 李铮 +3 位作者 齐天贵 周秋生 彭志宏 李小斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4160-4166,共7页
The mechanism of seeded precipitation of sodium aluminate solution was studied by measuring the seeded-precipitation rate and electrical conductivity online, as well as calculating the activity and fraction of ion pai... The mechanism of seeded precipitation of sodium aluminate solution was studied by measuring the seeded-precipitation rate and electrical conductivity online, as well as calculating the activity and fraction of ion pair. The results show that the electrical conductivity of sodium aluminate slurry linearly decreases with increasing aluminum hydroxide addition. Moreover, both the electrical conductivity of slurry and the difference in electrical conductivity between sodium aluminate solution and slurry remarkably decline in the first 60 min before gradually increasing in the preliminary 10 h and finally reaching almost the same level after 10 h. In low Na2 O concentration solution the activities of Na OH and Na Al(OH)4 in seeded precipitation are high, which can enlarge the difference in conductivity between slurry and solution. Additionally, more ion pairs exist in solution in preliminary seeded precipitation, and the adsorption of Na+Al(OH)4- on seed surface is likely to break the equilibrium of ion pair formation and to decrease the difference in conductivity in preliminary seeded precipitation. 展开更多
关键词 sodium aluminate solution seeded precipitation electrical conductivity activity coefficient ion pair
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Tribological effects of oxide based nanoparticles in lubricating oils 被引量:3
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作者 顾彩香 朱冠军 +2 位作者 李磊 田晓禹 朱光耀 《Journal of Marine Science and Application》 2009年第1期71-76,共6页
In order to enhance the tribological properties of lubricating oil, suitable surfactants such as Tween-20, Tween-60, Span-20 and Sodium sodecylbenzenesulfonate were selected and lubricating oils containing CeO2 and Ti... In order to enhance the tribological properties of lubricating oil, suitable surfactants such as Tween-20, Tween-60, Span-20 and Sodium sodecylbenzenesulfonate were selected and lubricating oils containing CeO2 and TiO2 nanoparticles were prepared. The morphology and size of CeO2 and TiO2 nanoparticles were examined with a transmission electron microscope (TEM). The tribological properties of the oils were tested using an MRS-1J four-ball tribotester. The research results show that when the proportion by weight of CeO2 nanoparticles to TiO2 nanoparticles is 1:3, and the total weight fraction is 0.6%, the lubricating oil has optimal anti-wear and friction reducing properties. The addition of CeO2 nanoparticles reduces the required amount of TiO2 nanoparticles. 展开更多
关键词 NANOPARTICLES SURFACTANTS lubricating oil tribological properties
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~1H-MRS在蛛网膜下腔出血性脑血管痉挛发生时的评价作用 被引量:1
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作者 全伟 李铁林 +10 位作者 陈光忠 姜晓丹 徐如祥 柯以铨 段传志 吕建平 张昊 谢伟 钟文军 陈颖东 陈凡帆 《南方医科大学学报》 CAS CSCD 北大核心 2006年第3期352-354,共3页
目的探讨活体质子磁共振波谱(1H-MRS)在蛛网膜下腔出血(SAH)性脑血管痉挛发生时的评价作用。方法采用两次注血法建立狗SAH模型,实验分为注射生理盐水组和注血组。于模型制作成功后3、7、14d分别进行1H-MRS检查扫描,记录胆碱(Cho)、N-乙... 目的探讨活体质子磁共振波谱(1H-MRS)在蛛网膜下腔出血(SAH)性脑血管痉挛发生时的评价作用。方法采用两次注血法建立狗SAH模型,实验分为注射生理盐水组和注血组。于模型制作成功后3、7、14d分别进行1H-MRS检查扫描,记录胆碱(Cho)、N-乙酰基天冬氨酸(NAA)和肌酸(Cr)的变化。1H-MRS扫描后即刻进行脑血管造影检查,测定基底动脉血管痉挛发生情况,与1H-MRS扫描结果加以比较分析。结果脑血管造影结果提示在第3天基底动脉血管发生明显痉挛,到第7天各段血管痉挛最为显著,第14天血管痉挛明显改善;1H-MRS的检测指标显示注血组各项指标在第3、7天变化较大,其中NAA在第3天下降到低谷,之后逐渐回升,至第14天接近正常水平;Cho在第3天稍有下降,然后上升,至第7天上升至高峰,尔后下降;而Cr则一直表现为上升趋势,但第7天后上升趋势明显放缓,与第14天相对含量相比差异无显著性(P>0.05)。1H-MRS功能检测结果与脑血管造影结果具有一定的吻合性。结论1H-MRS可用来监测蛛网膜下腔出血性脑血管痉挛发生时病程进展,是一种较好的功能影像学评价手段。 展开更多
关键词 体质磁共振波谱 蛛网膜下腔出血 血管痉挛 脑血管造影
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Studies on the Proton Pumping Activity of H^+-ATPase in Tonoplast Vesicles of Populus euphratica 被引量:6
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作者 刘群录 张旭家 +2 位作者 李义 王沙生 蒋湘宁 《Acta Botanica Sinica》 CSCD 2001年第5期495-500,共6页
Tonoplast-enriched vesicles were prepared from suspension-cultured Populus euphratica Oliv. cells by differential centrifugation and discontinuous sucrose density gradient centrifugation. The properties of the proton ... Tonoplast-enriched vesicles were prepared from suspension-cultured Populus euphratica Oliv. cells by differential centrifugation and discontinuous sucrose density gradient centrifugation. The properties of the proton pumping activity of H+-ATPases in tonoplast vesicles were studied by acridine orange fluorescent quenching measured at 22 degreesC. The proton pumping activity of ATPase was ATP-dependent with apparent Michaelis-Menten Constant (K-m) for ATP about 0.65 mmol/L. The optimal pH for H+-ATPases activity was 7.5. The proton pumping activity of H+-ATPase could be initiated by some divalent cations, Mg2+ being highly efficient, much more than Fe2+; and Ca2+, Cu2+ and Zn2+ were inefficient under the experimental condition. The proton translocation could be stimulated by halide anions, with potencies decreasing in the order Cl- > Br- > I- > F-. The proton pumping activity was greatly inhibited by N-ethylmaleimide (NEM), N, N'-dicyclohexylcarbodiimide (DCCD), NO3- and Bafilomycin A(1), but not by orthovanadate and azide. These results demonstrated that the H+-ATPase in the tonoplast of Populus euphratica belonged to vacuolar type ATPase. This work was the first time that tonoplast-enriched vesicles were isolated from Populus euphratica cells. 展开更多
关键词 Populus euphratica H+-ATPase proton pumping activity
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Adsorption and activation of copper ions on chalcopyrite surfaces:A new viewpoint of self-activation 被引量:9
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作者 邓久帅 文书明 +2 位作者 刘建 吴丹丹 丰奇成 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3955-3963,共9页
The adsorption behaviors of copper ions on chalcopyrite surfaces were investigated based on zeta potential measurements, X-ray photoelectron spectroscopy, copper ion adsorption experiments, first-principles calculatio... The adsorption behaviors of copper ions on chalcopyrite surfaces were investigated based on zeta potential measurements, X-ray photoelectron spectroscopy, copper ion adsorption experiments, first-principles calculations, and Hallimond tube cell flotation experiments. The results show that copper ions activate the chalcopyrite as a result of the interactions between copper ions and sulfur on the chalcopyrite surface. This adsorption increases the flotation rate under certain conditions, and this is beneficial for the flotation of chalcopyrite. The copper ions in the flotation pulp are mainly derived from surface oxidation dissolution and the release of fluid inclusions, and these effects enable chalcopyrite to be activated. 展开更多
关键词 CHALCOPYRITE copper ions ADSORPTION SELF-ACTIVATION
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Effects of Sunflower Artificial Aging on Seed Vigor and Physiological Characteristics 被引量:5
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作者 谭美莲 校凝凝 +2 位作者 严明芳 陈金风 严兴初 《Agricultural Science & Technology》 CAS 2010年第4期39-43,共5页
[Objective]The aim was to study the effects of sunflower artificial aging on seed vigor and physiological characteristics.[Method] The varieties of seed germination capacity,vigor of germination,germination index,vigo... [Objective]The aim was to study the effects of sunflower artificial aging on seed vigor and physiological characteristics.[Method] The varieties of seed germination capacity,vigor of germination,germination index,vigor index,peroxidase(POD) activity,superoxide dismutase(SOD) activity and malondialdehyde(MDA) content for four sunflower germplasms such as'SunM20','Deep Purple Minle','Da San Kui Hua 4'and'Ji Kui 24'were studied under high temperature and high humidity conditions(100% RH,45 ℃) for different days(0 d,2 d,4 d,6 d,8 d,10 d).[Result]The result showed that the germination capacity,vigor of germination,germination index,vigor index,POD activity,SOD activity declined gradually with the increase of seed aging days,whereas MDA content enhanced by degrees;The diggerences of resistance to artifical aging existed among the four accessions,'SunM20'was the most resistant one,and exhibited the strongest seed vigor,highest activities of two protective enzyme(POD,SOD) and lowest content of MDA at the uniform condition,moreover,the seed vigor and protective enzyme activities of'SunM20'changed slowest among the four materials during the aging process.[Conclusion]The distinct reduction of POD,SOD activities maybe the main reasons for the decrease of sunflower seed vigor at the artificial aging,and the gradual accumulation of a few MDA accelerated seeds aging. 展开更多
关键词 Sunflower germplasm Artificial aging Seed vigor The resistance to aging Physiological characteristics
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An emergency decision support system for the marine pollution 被引量:1
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作者 宋军 郭俊如 +7 位作者 牟林 刘玉龙 李琰 袁泽轶 李欢 高佳 王国松 姚志刚 《Marine Science Bulletin》 CAS 2015年第2期56-67,共12页
The paper introduces the research progress in an emergency decision support system for marine pollution (EDSS) in China seas and elaborates on the possible role of the Neutron Activation Analysis (NAA) method ther... The paper introduces the research progress in an emergency decision support system for marine pollution (EDSS) in China seas and elaborates on the possible role of the Neutron Activation Analysis (NAA) method therein. To deal with the increasingly grave situation of offshore pollution, the EDSS for China seas has been researching and developing. Based on the prediction and analysis of the ocean three-dimensional current field, this system makes an inference on the possible path of diffusion and influencing area of marine pollutants and possible location of pollution source, and in combination with the environmentally sensitive information related to the technical integration of GIS, it puts forward the decision, making support for minimizing the hazard caused by pollutants. This system has been operationalized and running for many years on the Bohai and Huanghai seas' Marine Pollutants Prediction and Early-Warning, and it has achieved successful experience for many times in the emergencies of China's coastal pollution accidents. At present, the environmental guarantee system directed against heavy metals and radioactive pollutants is in the experimental stage. As the NAA method is especially applicable to the detection of part of heavy metals and radioactive substances, it is of very important practical value for the new system to realize the monitoring, prediction and early-warning of ocean heavy metals and radioactive pollutants. 展开更多
关键词 marine pollution Neutron Activation Analysis ocean modeling
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Microstructure and mechanical properties of Fe_3Al alloys prepared by MA-PAS and MA-HP 被引量:3
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作者 王建 邢建东 +2 位作者 汤慧萍 杨保军 李亚宁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2408-2414,共7页
Fe3Al alloys with nearly full density were fabricated by plasma activated sintering(PAS) and hot pressing(HP) from mechanical alloyed Fe-28%Al(mole fraction) powders,respectively.It is found that A2-type Fe3Al a... Fe3Al alloys with nearly full density were fabricated by plasma activated sintering(PAS) and hot pressing(HP) from mechanical alloyed Fe-28%Al(mole fraction) powders,respectively.It is found that A2-type Fe3Al alloys were obtained by PAS,and they had a heterogeneous grain size distribution,most areas had a grain size smaller than 500 nm,and other areas had a grain size of about 1 μm.Different to PAS,D03-type Fe3Al alloys with a grain size of of 1-2 μm were obtained by HP.The compression testing results show that yield strength values of Fe3Al alloys fabricated by PAS and HP are almost equal at an elevated temperature,and the compression yield strength was about 100 MPa for all at 800 ℃.The room temperature compression ductility of Fe3Al alloys by PAS was about 20%,which was superior to that of Fe3Al alloys prepared by HP and casting. 展开更多
关键词 Fe3Al intermetallic plasma activated sintering hot pressing microstructure mechanical properties
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Synthesis of one-dimensional carbon nanostructures and their application as anode materials in lithium ion batteries 被引量:3
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作者 唐晶晶 杨娟 +2 位作者 周向阳 陈光辉 黄滨 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1079-1085,共7页
An efficient synthesis of carbon nanofibers by pyrolysis of as-prepared polypyrrole nanowires was reported. Under the subsequent KOH activation, a significant morphology variation was detected and the obtained sample ... An efficient synthesis of carbon nanofibers by pyrolysis of as-prepared polypyrrole nanowires was reported. Under the subsequent KOH activation, a significant morphology variation was detected and the obtained sample took on a ribbon-like structure. The morphology and structure of the carbon nanofibers and carbon nanoribbons were characterized. When the as-prepared one-dimensional carbon nanostructures were used as anode materials in lithium ion batteries, both of them exhibited superior cyclical stability and good rate properties. After 50 cycles, the reversible capacity of carbon nanofibers electrode maintained 530 mA·h/g. Concerning carbon nanoribbons, the reversible capacity is always larger than 850 mA·h/g and the reversible capacity retention after 23 cycles is 86%. 展开更多
关键词 carbon nanofibers carbon nanoribbons PYROLYSIS KOH activation lithium ion batteries
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