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岩土工程专业研究生课程教学中的“学―研”创新模式探索 被引量:1
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作者 刘先珊 谢强 许明 《科教导刊》 2023年第3期31-33,共3页
就岩土工程专业而言,构建以多元协同平台及项目为载体的研究生“学―研”教学创新模式亟待解决。文章分析了该专业研究生课程教学存在的问题,阐明师“教”生“学”的师生关系到师生共研的合作关系实现教学相长的关键。研究多元化教学模... 就岩土工程专业而言,构建以多元协同平台及项目为载体的研究生“学―研”教学创新模式亟待解决。文章分析了该专业研究生课程教学存在的问题,阐明师“教”生“学”的师生关系到师生共研的合作关系实现教学相长的关键。研究多元化教学模式、与前沿并进的课程内容部署及“学―研”理论的课程实践等相互融合的教学设计,探索研究生从“学”到“研”的角色转换、自主探究的模仿创新实践及教学策略。由此,在“导―学―研”的框架下有效提升岩土工程专业研究生的创新实践能力。 展开更多
关键词 工科究生 创新 岩土工程 “学―研” 模式
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中国科学院水利部水利科学研究院历史探实
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作者 张伟兵 周波 《自然科学史研究》 CSSCI CSCD 北大核心 2023年第4期435-446,共12页
1957年在国务院科学规划委员会的指导下,中国科学院、水利部、电力部和交通部达成协议,决定将中国科学院水工研究室和水利部北京水利科学研究院合并,成立由中国科学院和水利部共同领导的水利科学研究机构。国务院的介入和4个部级机构的... 1957年在国务院科学规划委员会的指导下,中国科学院、水利部、电力部和交通部达成协议,决定将中国科学院水工研究室和水利部北京水利科学研究院合并,成立由中国科学院和水利部共同领导的水利科学研究机构。国务院的介入和4个部级机构的共同决策,注定此次合并事件非同寻常,在新中国水利科技发展史上有着重要地位和意义。依据档案、人物传记、报刊、史志资料等,本文对此次合并的缘由、过程、结果,以及国务院科学规划委员会在合并中的作用进行了论述。文章指出,此次合并是国家主导下的一次对全国水利科研力量布局的优化和调整,也是中华人民共和国成立初期为建立高效的水利科研体系而进行的一次积极探索。新机构的成立不仅体现了国家倡导的在科学研究领域增产节约的精神,而且使高级水利研究人才布局进一步优化,确立了新机构在全国水利科学研究中的中心地位,为顺利完成十二年科技规划的水利工作奠定了基础。 展开更多
关键词 中国科院水工究室 水利部北京水利科究院 国务院科规划委员会 机构 合并
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现代小学数学实践教学研究与探讨 被引量:1
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作者 豆莉萍 《科技资讯》 2009年第10期205-205,共1页
教材并不是培养当今社会所需人才的圣经、宝典。我们要从把教材内容从枯燥无味转化为富有情趣、把书本数学转化为生活数学、把学生由简单的操作工转化为知识的探究者、把计算方法统一化转化为计算方法多样化等几个方面对教材进行合理、... 教材并不是培养当今社会所需人才的圣经、宝典。我们要从把教材内容从枯燥无味转化为富有情趣、把书本数学转化为生活数学、把学生由简单的操作工转化为知识的探究者、把计算方法统一化转化为计算方法多样化等几个方面对教材进行合理、灵活的利用,使自己成为教材的积极实践者和创建者! 展开更多
关键词 教材 培养 方法 转化
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齿轮耦合的转子-轴承系统非线性动力特性的研究 被引量:31
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作者 张锁怀 李忆平 丘大谋 《机械工程学报》 EI CAS CSCD 北大核心 2001年第9期53-57,61,共6页
在考虑齿轮时变啮合刚度、齿侧间隙、脱齿、挤齿及齿背接触 等因素的情况下,建立了齿轮耦合的转子—滑动轴承系统的多自由度动力学模型。用数值方 法研究了该系统的质量不平衡响应,结果发现,由于齿轮时变啮合刚度的影响,随着转速的... 在考虑齿轮时变啮合刚度、齿侧间隙、脱齿、挤齿及齿背接触 等因素的情况下,建立了齿轮耦合的转子—滑动轴承系统的多自由度动力学模型。用数值方 法研究了该系统的质量不平衡响应,结果发现,由于齿轮时变啮合刚度的影响,随着转速的 增加,系统动力学响应首先由周期运动向准周期运动变化,当转速超过某一值时,系统的响应将由准周期运动发展为混沌运动;由于混沌运动,转子将沿齿轮中心线方向产生很大的变 形,脱齿、齿背接触及挤齿现象也将发生,可能导致系统产生破坏。 展开更多
关键词 齿侧间隙 时变啮合刚度 分岔 混沌 非线性动力 齿轮耦合 转子-轴承系统
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The State of Geological Sciences in the USSR by the Mid-Twentieth Century
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作者 Ivan Petrovich VTOROV 《Chinese Annals of History of Science and Technology》 2024年第1期125-130,共6页
The November 1948 open session of the Institute of Geological Sciences AS USSR was previously unknown,in contrast to the August 1948 session of VASKhNIL.The publication of the transcript of the session of geologists i... The November 1948 open session of the Institute of Geological Sciences AS USSR was previously unknown,in contrast to the August 1948 session of VASKhNIL.The publication of the transcript of the session of geologists is based on the original verified transcript from the Geological Institute and the Archive RAS.It presented reports on the main scientific directions of geology:stratigraphy,the Quaternary geology,lithology,geotectonics,petrography and petrology,mineralogy and geochemistry,and the geology of ore and coal deposits.This thick book details all the Q&A sessions,discussions of theories,methods,and practice among the leading Soviet geoscientists.The session and its resolution describe the situation and development of geology in the USSR in the mid-twentieth century as well as the collateral impact of the Lysenko affair on the earth sciences in the USSR. 展开更多
关键词 history of geology geological sciences book review 1948 session VASKhNIL 1948 session of the Institute of Geological Sciences AS USSR
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胶州湾北部软底大型底栖动物丰度和生物量的研究 被引量:17
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作者 于子山 张志南 王诗红 《中国海洋大学学报(自然科学版)》 CAS CSCD 2000年第z1期-,共7页
1995年3~11月对胶州湾北部软底海域进行了 两月一次的大型底栖动物调查。调查期间,大型底栖动物总平均丰度和总平均生物量分别为 1891.3 inds./m2和41.9 g.w.w/m2。与该海域有关大型底栖动物丰度和生物量的历史 资料相比较,本研究所... 1995年3~11月对胶州湾北部软底海域进行了 两月一次的大型底栖动物调查。调查期间,大型底栖动物总平均丰度和总平均生物量分别为 1891.3 inds./m2和41.9 g.w.w/m2。与该海域有关大型底栖动物丰度和生物量的历史 资料相比较,本研究所得到的大型底栖动物丰度值显著增加,生物量值则有较明显的下降, 初步分析了发生这些变化主要原因。丰度和生物量比较曲线表明,所研究海域底栖生物群落 处于中等干扰(即污染的影响 )状态。 展开更多
关键词 胶州湾 大型底栖动物 丰度 生物量
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Mapping the Research Landscape of Language Development in Autistic Children: A Preliminary Scientometric Analysis
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作者 Zhonghua WU Le CHENG 《Chinese Journal of Applied Linguistics》 2024年第4期670-686,688,共18页
Children with autism spectrum disorder(ASD)often encounter difficulties in language learning and utilization,a concern that has gained significant academic attention,particularly given the widespread occurrence of ASD... Children with autism spectrum disorder(ASD)often encounter difficulties in language learning and utilization,a concern that has gained significant academic attention,particularly given the widespread occurrence of ASD globally.Previous reviews,however,have relied on empirical observations rather than a more rigorous selection criterion.This preliminary study seeks to systematize the scientific knowledge base regarding language development in autistic children by utilizing the analysis tool Citespace 6.2.R5.We visualized and analyzed research patterns and trends regarding autism by drawing data from the Web of Science.Through document citation and emerging trend analyses,seven key research clusters and their chronological associations are identified,along with research hotspots such as language disorder diagnosis and intervention,social communication,language acquisition,and multilingual and multicultural influences.Research findings show that there exist some issues with the current research,including small sample sizes,the need for further investigation into receptive language development,and a lack of cross-cultural comparative studies.Meanwhile,the scope and depth of interdisciplinary research on language development in autistic children also need to be further enhanced.The research contributes to the extant literature by providing valuable references for autism researchers and practitioners. 展开更多
关键词 language development autistic children scientometric analysis ASD tentative study
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调水工程输水管道建设对沿线景观格局影响的研究 被引量:1
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作者 吴钢 董孟婷 +2 位作者 唐明方 李思远 曹慧明 《河南理工大学学报(自然科学版)》 CAS 北大核心 2016年第3期373-380,共8页
为了了解调水工程输水管道建设对沿线景观格局的影响,选取南水北调中线一期工程河北省易县段调水工程输水管道建设区域为研究对象,以50-3 000 m划分不同宽度研究区,利用Arc GIS和FRAGSTATS软件,研究了施工建设前、中、后期沿线土地利用... 为了了解调水工程输水管道建设对沿线景观格局的影响,选取南水北调中线一期工程河北省易县段调水工程输水管道建设区域为研究对象,以50-3 000 m划分不同宽度研究区,利用Arc GIS和FRAGSTATS软件,研究了施工建设前、中、后期沿线土地利用类型的变化,并且分别计算不同宽度及整体景观的景观指数,分析管道建设对沿线区域景观格局的影响。研究结果表明:管道工程建设期的对区域土地利用方式产生的影响较为明显和强烈,工程建设对施工作业带两侧100 m范围内影响最为明显。 展开更多
关键词 南水北调 输水管道建设 景观指数 遥感影像
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Evidence-based Clinical Chinese Medicine:What Has Changed Over the Past 20 Years
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作者 Charlie Changli Xue Anthony Lin Zhang +2 位作者 Brian H May Louise Pobjoy Iris Wenyu Zhou 《广州中医药大学学报》 CAS 2024年第10期2555-2567,共13页
Chinese medicine has been used for centuries to treat a range of health conditions.This history has produced a wealth of classical literature,case studies and clinical research data detailing its use and effectiveness... Chinese medicine has been used for centuries to treat a range of health conditions.This history has produced a wealth of classical literature,case studies and clinical research data detailing its use and effectiveness.However,high-quality and conclusive evidence that meets modern requirements for clinical decision support is lacking.This evidence gap limits the integration of Chinese medicine with contemporary medicine,which in turn limits global access and acceptance of Chinese medicine as a form of safe and effective health care.Over the past 20 years,researchers and organisations around the world,including the World Health Organization(WHO)and United Nations,have worked to support the integration of traditional medicines,such as Chinese medicine,with conventional medicines to improve global health care.This paper provides an overview of Chinese medicine studies published in the top four general medical journals(BMJ,JAMA,Lancet and New England Journal of Medicine)from February 2005 to February 2024 in the past 20 years to highlight the progress in the development of this evidence base.It also highlights key actions taken to promote evidence-based clinical Chinese medicine,including product and practitioner regulation,formalising education standards,and international collaborations.Research conducted at the China-Australia International Research Centre for Chinese Medicine demonstrates the benefits of such a collaboration.Through development of its unique and inclusive‘whole-evidence’approach,plus clinical studies and systematic reviews,the Centre has significantly contributed to the evidence base for clinical Chinese medicine.In addition,its high-impact papers and groundbreaking monographs have been cited in international conventional medicine guidelines.While progress has certainly been made during the past 20 years to build a stronger evidence base for clinical Chinese medicine,there is still a considerable gap that limits its integration with conventional medicine.Future funding and research are needed to continue this work and achieve to safe,effective and accessible traditional medicine as part of the WHO’s Universal Health Coverage strategy. 展开更多
关键词 evidence-based medicine traditional Chinese medicine whole-evidence approach integrated traditional Chinese and western medicine integrative medicine China-Australia International Research Centre for Chinese Medicine
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Multicenter Clinical Randomized Controlled Trial and Network Pharmacology Analysis of Zhenzhu Qingyuan Granules for the Treatment of Gastroesophageal Reflux Disease
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作者 Mengge Li Zhibo Dang +7 位作者 Peiguo Qian Zhenhuan Yang Lei Luo Bo Li Xingzhou Xia Yingjie Ma Zhongqin Dang Yuliang Wang 《Chinese Medicine and Natural Products》 CAS 2024年第3期106-116,共11页
Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network... Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network pharmacology.Methods Patients with gastroesophageal reflux disease(GERD)of liver–stomach stagnant heat pattern who met the inclusion and exclusion criteria were randomly divided into the control group and the observation group.The control group received oral rabeprazole,whereas the observation group were given Zhenzhu Qingyuan Granules in addition to the rabeprazole.The treatment duration was 8 weeks.Clinical efficacy was observed in both groups after 8 weeks.Network pharmacology was used to analyze the action targets of ZhenzhuQingyuanGranules and the genes related to GERD,and core targets were inferred.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted to explore the potential mechanisms of this formula.Results The clinical research results showed that the total effective rate in the treatment group was 92.68%,compared with 70.00%in the control group,with a statistically significant difference(p<0.05).After treatment,both Chinese medicine syndrome score and endoscopic score improved in both groups compared with before treatment(p<0.05),and the treatment group showed greater improvement than the control group(p<0.05).Network pharmacology identified effective components of Zhenzhu Qingyuan Granules for treating GERD,including quercetin,luteolin,andβ-sitosterol,with potential action targets such as tumor protein 53(TP53),protein kinase B(AKT1),and tumor necrosis factor.Conclusion Zhenzhu Qingyuan Granules can significantly improve clinical symptoms in patients with GERD of liver–stomach stagnated heat pattern,enhance clinical efficacy,and have high safety.This formula may exert therapeutic effects through multiple targets and pathways. 展开更多
关键词 gastroesophageal reflux disease Zhenzhu Qingyuan Granules liver–stomach stagnated heat syndrome randomized controlled trial network pharmacology
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《结构化学》简介
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作者 《结构化学》编辑部 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期716-716,共1页
《结构化学》是由中国科学院主管,中国化学会、中国科学院福建物质结构研究所主办的学术性期刊。1982年由我国著名化学家卢嘉锡院士创办并担任主编,现任主编是著名化学家吴新涛院士。《结构化学》主要报道晶体学,量子化学,药物、材料和... 《结构化学》是由中国科学院主管,中国化学会、中国科学院福建物质结构研究所主办的学术性期刊。1982年由我国著名化学家卢嘉锡院士创办并担任主编,现任主编是著名化学家吴新涛院士。《结构化学》主要报道晶体学,量子化学,药物、材料和催化剂等领域物质性能与结构关系的文章。报道的内容涉及有机化学、无机化学、合成化学、结构化学、材料科学、药物化学、晶体学、理论化学等学科中的微观物质结构与性能关系的研究成果或阶段性成果。与此同时本刊也报道用谱学等物理方法解析物质结构、阐述物质结构与性能关系的论文。 展开更多
关键词 结构化 物质结构 卢嘉锡 中国化 中国科 量子化 吴新
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食品添加剂在我国食品加工中的应用现状 被引量:5
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作者 李其晔 《保鲜与加工》 CAS 2023年第4期68-73,共6页
食品添加剂在现代食品工业生产中占据着非常重要的地位,与人们的日常饮食安全和身体健康息息相关。综述了我国食品添加剂的定义、作用、种类、相关法律法规和加工特点等,提出了食品添加剂在食品加工应用中存在的问题及相应解决措施,对... 食品添加剂在现代食品工业生产中占据着非常重要的地位,与人们的日常饮食安全和身体健康息息相关。综述了我国食品添加剂的定义、作用、种类、相关法律法规和加工特点等,提出了食品添加剂在食品加工应用中存在的问题及相应解决措施,对进一步丰富我国食品添加剂理论研究,推动食品加工业高质量发展具有重要的社会和经济意义。 展开更多
关键词 食品添加剂 使用规范 加工 生产 安全 监管
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Phytogenetic Studies on Intergeneric Hybridization Between Brassica napus and Matthiola incana 被引量:13
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作者 罗鹏 傅华龙 +3 位作者 蓝泽蘧 周颂东 周洪芳 罗晴 《Acta Botanica Sinica》 CSCD 2003年第4期432-436,共5页
The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of ra... The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained. 展开更多
关键词 Brassica napus Matthiola incana intergeneric hybridization phytogenetic studies
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Reaction mechanisms of low-grade molybdenum concentrate during calcification roasting process 被引量:6
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作者 甘敏 范晓慧 +6 位作者 陈许玲 吴程骞 季志云 王送荣 汪国靖 邱冠周 姜涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期3015-3023,共9页
The effects of Ca-based additives on roasting properties of low-grade molybdenum concentrate were studied. The resultsshow that calcium-based additives can react with molybdenum concentrate to form CaSO4 and CaMoO4. T... The effects of Ca-based additives on roasting properties of low-grade molybdenum concentrate were studied. The resultsshow that calcium-based additives can react with molybdenum concentrate to form CaSO4 and CaMoO4. The initial oxidationtemperature of MoS2 is 450℃, while the formation of CaMoO4 and CaSO4 occurs above 500℃. The whole calcification reactionsare nearly completed between 600 and 650℃. However, raising the temperature further helps for the formation of CaMoO4 but isdisadvantageous to sulfur fixing rate and molybdenum retention rate. Calcification efficiency of Ca-based additives follows theorder: Ca(OH)2〉CaO〉CaCO3. With increasing the dosage of Ca(OH)2, the molybdenum retention rate and sulfur-fixing rate rise, butexcessive dosages would consume more acid during leaching process. The appropriate mass ratio of Ca(OH)2 to molybdenumconcentrate is 1:1. When roasted at 650 ℃ for 90 min, the molybdenum retention rate and the sulfur-fixing rate of low-grademolybdenum concentrate reach 100% and 92.92%, respectively, and the dissolution rate of molybdenum achieves 99.12% withcalcines being leached by sulphuric acid. 展开更多
关键词 molybdenum concentrate calcification roasting reaction mechanism thermodynamic analysis phase transformation
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Determination of Loratadine in Human Plasma by High Performance Liquid Chromatography-Electrospray Mass Spectrometry and Studies on Its Pharmacokinetics and Relative Bioavailability 被引量:3
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作者 陈钧 高科攀 +5 位作者 史振祺 陆伟 蒋新国 荣征星 黄霞 陈红专 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第4期137-141,共5页
A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined ... A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets. 展开更多
关键词 LORATADINE HPLC MS PHARMACOKINETICS BIOAVAILABILITY
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Effects of 2,4-D and 6-BA on Callus Induction and Plantlet Regeneration from Mature Embryos of Hsien Rice 被引量:15
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作者 苗春波 万志刚 孙丙耀 《Agricultural Science & Technology》 CAS 2009年第4期22-26,共5页
[ Objective] In order to study the effects of 2,4-D and 6-BA on callus cultivation from mature embryos of hsien rice. [ Method] 2,4-D and 6-BA were set at different concentrations in callus induction and differentiati... [ Objective] In order to study the effects of 2,4-D and 6-BA on callus cultivation from mature embryos of hsien rice. [ Method] 2,4-D and 6-BA were set at different concentrations in callus induction and differentiation mediums to study their effects on callus induction, seedling formation and regenerated seedlings rooting. [ Result] In the callus induction medium treated with 0.5 mg/L 2,4-D, the callus induction effects on the varieties like Jiayu 948, Yanghui 559, Yangxian 6547, Zhong'erruanzhan, Minghui 86, Guanghui 998 and Zunxian 3 were the best; If 0.2 mg/L 6-BA was added into the callus induction medium containing the optimum level of 2,4-D, there was no obvious effect on induction rate of callus, but the differentiation and seedling of callus were inhibited; If the concentration of 6-BA was reduced appropriately in the differentiation medium, the seedling rate of callus would be not only no decreased but increased, meanwhile the quality of regenerated plants would be improved. [ Conclusion] The study results provided some references for the reasonable uses of 2,4-D and 6-BA in callus culture of hsien rice. 展开更多
关键词 Hsien rice CALLUS 2 4-D 6-BA
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Cytological Studies on the Development of Sieve Element and Floral Nectary Tissue in Arabidopsis thaliana 被引量:4
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作者 祝建 胡正海 《Acta Botanica Sinica》 CSCD 2002年第1期9-14,共6页
Ultrastructural changes in the sieve element and dense cells of nectariferous tissue during the development of floral nectary in Arabidopsis thaliana L. were investigated with transmission electron microscopy. Samples... Ultrastructural changes in the sieve element and dense cells of nectariferous tissue during the development of floral nectary in Arabidopsis thaliana L. were investigated with transmission electron microscopy. Samples were prepared with high pressure freezing and freeze substitution techniques. The ultrastructure of dense cell was similar to that of sieve element at its early developmental stage. With the concurrent agglutination of chromatin in the nucleus, the abnormal location of organelles and the high density of cytoplasm, the ultrastructural characteristics in die dense cells of the nectariferous tissue and in the sieve element are matched with those of the programmed cell death in animal and plant reported in recent years. The disorganization of nucleus and most organelles in the differentiation of sieve elements and dense cells is closely associated with the transportation and modification of pre-nectar and the transference of nectar. This suggests that the cytological changes in sieve element and nectariferous tissue are closely associated with the nectary functional activities. 展开更多
关键词 floral nectary DEVELOPMENT ULTRASTRUCTURE nectariferous tissue sieve element Arabidopsis thaliana
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New Xanthones from Swertia decora 被引量:1
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作者 肖怀 陆阳 +2 位作者 陈泽乃 刘光明 钱金栿 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期172-174,共3页
From the CHCl3 part of Swertia decora Franch., a traditional medicinal herb of China, two new xanthones, swertiadecoraxanthone-I and swertiadecoraxanthone-II along with four known compounds have been isolated and iden... From the CHCl3 part of Swertia decora Franch., a traditional medicinal herb of China, two new xanthones, swertiadecoraxanthone-I and swertiadecoraxanthone-II along with four known compounds have been isolated and identified on the basis of spectral analysis and chemical evidence. 展开更多
关键词 Swertia decora GENTIANACEAE XANTHONE Swertiadecoraxanthone-II
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Antecedents and performance consequences of governance structures in R&D alliances 被引量:1
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作者 林艺馨 荷世平 吴学良 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期360-366,共7页
Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research an... Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa. 展开更多
关键词 organizational governance structure organizational control resource-based review transaction cost economics R& D alliance
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顾广圻与《文选》学研究 被引量:5
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作者 穆克宏 《文学遗产》 CSSCI 北大核心 2006年第3期15-21,共7页
本文论述了清代著名校勘学家顾广圻与《文选》学研究的关系。顾氏校勘的李善注《文选》,为《选》学研究作出了重要的贡献,具有划时代的意义,至今仍是我们学习和研究《文选》的重要版本。
关键词 顾广圻 《文选》 《文选考异》 中国 评论
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