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石油天然气项目土壤污染特征与复垦防控对策 被引量:2
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作者 张世文 沈重阳 +3 位作者 黄元仿 周妍 李贞 尹群 《蚌埠学院学报》 2019年第5期119-122,共4页
基于文献和自然资源部矿山地质环境保护与土地复垦方案评审材料的归纳总结,阐述了我国石油天然气项目土壤污染现状与危害,并根据石油天然气生产工艺,明确不同环节的污染源和类型。在此基础上,从完善立法,明确责任界线,强化企业污染防控... 基于文献和自然资源部矿山地质环境保护与土地复垦方案评审材料的归纳总结,阐述了我国石油天然气项目土壤污染现状与危害,并根据石油天然气生产工艺,明确不同环节的污染源和类型。在此基础上,从完善立法,明确责任界线,强化企业污染防控意识;优化技术模式,预防优先;开展调查,差别化选择修复方式等三个方面提出了我国石油天然气项目的复垦防控对策。 展开更多
关键词 石油天然气项目 土壤污染 复垦 防控对策
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临床医学专业八年制学生对口腔医学教学内容需求的调查 被引量:1
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作者 李倩 储晓天 +4 位作者 郭春岚 杨文东 李珍 董海涛 赵继志 《全科口腔医学电子杂志》 2018年第33期182-184,共3页
目的调查临床医学专业八年制学生对口腔医学教学内容需求,为优化课程、增强临床医学生口腔医学教学实用性的教学改革提供依据。方法以北京协和医学院2012级八年制学生为研究对象,半开放式问卷调查八年制临床专业医学生口腔医学教学内容... 目的调查临床医学专业八年制学生对口腔医学教学内容需求,为优化课程、增强临床医学生口腔医学教学实用性的教学改革提供依据。方法以北京协和医学院2012级八年制学生为研究对象,半开放式问卷调查八年制临床专业医学生口腔医学教学内容意向。结果临床医学专业八年制学生对口腔健康维护的正确方法、内科疾病的口腔表现及孕产妇口腔保健专题的选择率最高(89%以上)。并提出对口腔健康自我评测、传染病和性传播疾病的口腔表现与治疗等专题知识的需求。结论临床医学专业八年制学生对口腔医学教学内容的需求主要在临床多学科与口腔科的联系和自身口腔健康维护两个方面,调查结果为课程优化和教学改革提供依据。 展开更多
关键词 临床医学专业 口腔医学 实用性 教学内容
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Analysis on sensitivity and landscape ecological spatial structure of site resources 被引量:1
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作者 lizhen HEFang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第2期215-221,共7页
This article establishes a set of indicators and standards for landscape ecological sensitivity analysis of site resources by using the theories and approaches of landscape ecology. It uses landscape diversity index(H... This article establishes a set of indicators and standards for landscape ecological sensitivity analysis of site resources by using the theories and approaches of landscape ecology. It uses landscape diversity index(H), evenness(E), natural degree(N), contrast degree(C) to study spatial structure and landscape heterogeneity of site resources and thus provides a qualitative-quantitative evaluation method for land planning and management of small, medium scale areas. The analysis of Yantian District, Shenzhen of China showed that Wutong Mountain belonged to high landscape ecological sensitivity area, Sanzhoutian Reservoir and Shangping Reservoir were medium landscape sensitivity area and high ecological sensitivity area; Dameisha and Xiaomeisha belonged to medium sensitivity area caused by the decline of natural ecological areas. Shatoujiao, Yantian Pier belonged to low sensitivity area but urban landscape ecological development had reshaped and influenced their landscape ecological roles in a great extent. Suggestions on planning, protection goals and development intensity of each site or district were raised. 展开更多
关键词 sensitivity area site resource landscape heterogeneity scale landscape architecture
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辽宁省数字乡村发展就绪度评价研究 被引量:8
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作者 李振 张瑜 《当代农村财经》 2022年第2期7-13,共7页
近年来我国数字经济发展活跃,数字城市发展已取得显著成效,随着国家数字乡村战略的实施,数字化建设逐步向农村地区下沉渗透,数字技术在乡村的应用为乡村振兴提供了全新方向,我国乡村振兴进入新的发展阶段。本文以辽宁省数字乡村发展为... 近年来我国数字经济发展活跃,数字城市发展已取得显著成效,随着国家数字乡村战略的实施,数字化建设逐步向农村地区下沉渗透,数字技术在乡村的应用为乡村振兴提供了全新方向,我国乡村振兴进入新的发展阶段。本文以辽宁省数字乡村发展为研究对象,通过分析辽宁省数字乡村的发展现状,找寻目前辽宁省数字乡村发展存在的问题,构建辽宁省数字乡村发展就绪度评价指标体系,并运用APH和熵值法组合预测法计算数字乡村发展各指标权重,基于结果提出辽宁省数字发展提供发展对策建议,以期加快辽宁省数字乡村发展的进程。 展开更多
关键词 数字乡村 就绪度 评价组合 预测法
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选煤厂重介质分选智能控制系统研究 被引量:5
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作者 李真 《自动化应用》 2021年第1期1-3,共3页
针对选煤厂重介质分选系统悬浮液液位、密度的时变性、耦合性以及非线性特点,设计基于模糊PID控制的智能控制系统,稳定悬浮液密度,实现悬浮液液位的动态平衡。根据选煤厂重介质分选系统操作经验和各输入、输出变量的理论值,设计模糊子... 针对选煤厂重介质分选系统悬浮液液位、密度的时变性、耦合性以及非线性特点,设计基于模糊PID控制的智能控制系统,稳定悬浮液密度,实现悬浮液液位的动态平衡。根据选煤厂重介质分选系统操作经验和各输入、输出变量的理论值,设计模糊子集和论域、模糊控制规则,建立基于悬浮液液位、密度的模糊控制器,实现模糊PID控制。仿真结果表明,与原PID控制方案相比,模糊PID控制方案的控制精度更高,跟随性更好,保证了分选系统液位的动态平衡,悬浮物密度的稳定。 展开更多
关键词 模糊PID 耦合性 时变 液位 密度 重介质分选
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The Report of Antimutagenicity and Mutagenicity of 7 Kinds Natrual Edible Plants and Vegetables
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作者 Wei lizhen +2 位作者 Zhao Zezhen 《癌变.畸变.突变》 CAS CSCD 2001年第4期234-235,共2页
关键词 天然可食用植物 蔬菜 抗突变作用 致突变性
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The 2008 Olympic Games:Opportunities and Challenges for Sports Marketing
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作者 lizhen 《China's Foreign Trade》 2008年第15期57-58,共2页
Sport marketing refers to the spe- cific application of marketing principles to sport products(e.g., teams,leagues,events,etc.)to- gether with the marketing of non-sports products(e.g.,cigarettes,beer,long- distance p... Sport marketing refers to the spe- cific application of marketing principles to sport products(e.g., teams,leagues,events,etc.)to- gether with the marketing of non-sports products(e.g.,cigarettes,beer,long- distance phone service,etc.)through as- sociations with various sports. The explosive growth of sports marketing occurred at the 1984 Summer Olympics in Los Angeles,when corporate sponsors used the Games as a platform to market their brands.Coca-Cola,for ex- 展开更多
关键词 北京奥运会 体育经济 运动市场 商机
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数字模型在煤矿生产中的应用
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作者 李振 曹鹏 高钱存 《煤矿现代化》 2021年第6期147-148,151,共3页
构建模型管理系统,在矿井生产管理中实现了地质数据、开采设计、生产计划等工作信息的数字化传递,链接“信息孤岛”,对生产管理数据信息进行融合,实现煤矿生产模型化管理。
关键词 地质模型 生产计划 模型化管理
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Extraction of uranium(VI) with N-octanoylpyrrolidine in sulfonated kerosene
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作者 lizhen HANJing-Tian 《Nuclear Science and Techniques》 SCIE CAS CSCD 2000年第3期205-208,共4页
Extraction of uranium with N-octanoylpyrrolidine (OPOD) in sulfonated kerosene from aqueous nitric acid media has been studied. The dependence of the extraction distribution ratios on the concentrations of aqueous nit... Extraction of uranium with N-octanoylpyrrolidine (OPOD) in sulfonated kerosene from aqueous nitric acid media has been studied. The dependence of the extraction distribution ratios on the concentrations of aqueous nitric acid, extractant, salting-out agent and the temperature was investigated. The constitution of extracted complex was established, and the related thermodynamic functions were calculated. 展开更多
关键词 铀(Ⅵ) 核燃料 溶剂萃取 分离 萃取剂 N-辛酰基吡咯烷
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34份黄秋葵种质资源遗传多样性的iPBS分析 被引量:3
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作者 张景荣 张聪 +7 位作者 叶昌华 肖宇 刘玉珊 杨马进 韩菊兰 李臻 冯媛媛 卓明 《分子植物育种》 CAS 北大核心 2021年第15期5180-5188,共9页
为了探讨黄秋葵种质资源间的遗传关系,本研究利用引物结合位点扩增(inter-primer binding site,iPBS)标记对34份秋葵种质进行遗传多样性和亲缘关系分析。结果显示,12条iPBS引物共扩增出122条谱带,其中多态性谱带105条,多态性比率为80.45... 为了探讨黄秋葵种质资源间的遗传关系,本研究利用引物结合位点扩增(inter-primer binding site,iPBS)标记对34份秋葵种质进行遗传多样性和亲缘关系分析。结果显示,12条iPBS引物共扩增出122条谱带,其中多态性谱带105条,多态性比率为80.45%。运用PopGene 32软件计算得到34份种质资源的有效等位基因数(Ne)范围为1.6509~1.9899,平均值为1.9074;Nei's基因指数(H)范围为0.3943~0.4975,平均值为0.4746;Shannon's信息指数(I)范围为0.5833~0.6906,平均值为0.6673;采用NTsys 2.10e软件计算得到34份秋葵种质间的遗传相似系数在0.3936~0.9524之间;这些参数表明黄秋葵具有丰富的遗传多样性,且遗传变异水平较高。基于非加权组平均法(UPGMA)聚类结果表明,以遗传相似系数0.76为阈值,可将34份黄秋葵种质材料划分为6个组(Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ和Ⅵ),其中,在遗传相似系数大概为0.78处,Ⅱ类又可分为4个亚类有20份种质;各种质之间的亲缘关系与地理来源有一定的相关性,但不完全一致,材料间存在交叉现象。研究结果表明,iPBS技术可用于黄秋葵种质的鉴别以及遗传多态性的研究。本研究为黄秋葵资源的有效利用、遗传育种中亲本组合选配提供参考。 展开更多
关键词 秋葵 iPBS标记 遗传多样性 聚类分析
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硅胶膜离心柱法能高效、可靠地提取黄秋葵的DNA 被引量:3
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作者 张景荣 冯媛媛 +5 位作者 叶昌华 张聪 肖宇 李臻 白冯 王辉 《分子植物育种》 CAS CSCD 北大核心 2019年第17期5681-5686,共6页
黄秋葵(Abelmoschus esculentus)组织中富含影响其DNA提取质量的多糖、多酚。为探究这一特性,本研究以黄秋葵幼叶为材料,探索了一种新的基因组DNA提取方法——硅胶膜离心柱法,利用硅胶膜离心柱与自配的溶液提取了高质量的DNA。此法先用... 黄秋葵(Abelmoschus esculentus)组织中富含影响其DNA提取质量的多糖、多酚。为探究这一特性,本研究以黄秋葵幼叶为材料,探索了一种新的基因组DNA提取方法——硅胶膜离心柱法,利用硅胶膜离心柱与自配的溶液提取了高质量的DNA。此法先用不含十六烷基三甲基溴化铵(cetyl-trimethyl-ammonium bromide, CTAB)的缓冲液去除一部分次生代谢物;然后用3%CTAB缓冲液分离DNA;再用氯仿/异戊醇(24:1)抽提,之后用硅胶膜离心柱纯化DNA。运用琼脂糖凝胶电泳、ISSR-PCR扩增和限制性酶切等方法检测DNA的质量,并与传统CTAB法、十二烷基硫酸钠(sodium dodecyl sulfate, SDS)法和高盐低pH法进行比较分析。结果表明,本法提取的DNA完整性好,纯度高;能被Eco RⅠ完全消化;ISSR扩增得到的条带最清晰、多态性好,明显优于其它3种传统方法。此外,本方法也成功用于石斛(Dendrobium)、葡萄(Vitis spp.)、无花果(Ficus carica)、芦荟(Aloe vera)等植物基因组DNA的提取,因此具有广泛的适用性,可为富含多糖植物基因组DNA的提取提供参考。 展开更多
关键词 黄秋葵(Abelmoschus esculentus) DNA提取 次生代谢物 硅胶膜离心柱
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Paleoclimatic significance of mineral magnetic properties of loess sediments in northeastern Qinghai- Tibetan Plateau 被引量:9
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作者 WANGXiaoyong LUHuayu +2 位作者 lizhen DENGChenglong TANHongbing 《Chinese Science Bulletin》 SCIE EI CAS 2003年第19期2126-2133,共8页
Loess deposit in the northeastern Qinghai-Tibetan Plateau offers an excellent record of climate and environment changes in this region. We have conducted multiparameter mineral magnetic analyses of samples of loess de... Loess deposit in the northeastern Qinghai-Tibetan Plateau offers an excellent record of climate and environment changes in this region. We have conducted multiparameter mineral magnetic analyses of samples of loess deposits from the Dongchuan, Lalakou and Panzishan sections. The methods used include magnetic susceptibility, frequency-dependent susceptibility, temperature-dependent susceptibility, isothermal remanent magnetization acquisition, and magnetic hysteresis loops. The results reveal that magnetite is the dominant contributor to magnetic susceptibility. Maghemite and hematite is also present in the loess layers and paleosol horizons. The higher concentration of maghemite in paleosols suggests that the formation of maghemite occurred during in situ pedogenesis, which plays an important role in the enhancement of the magnetic susceptibility. Similar to that in the Chinese Loess Plateau lying to the east of the Liupan Mountains, magnetic granulometry in the studied loess and paleosols is predominantly pseudo-single-domain (PSD). However, the mean grain-size of the ferrimagnetic minerals in loess is evidently coarser (larger PSD and multidomain-like) than in paleosols (mainly PSD). The magnetic susceptibility of loess and paleosols is positively correlated with the content of ultrafine magnetite/maghemite grains, and hence with the intensity of in situ pedogenesis. Therefore, the enhanced magnetic susceptibility in the studied loess-paleosol sequences can be interpreted as being due to climatically induced in situ pedogenesis. 展开更多
关键词 古气候 矿石 磁性质 黄土沉积 东北地区 青海 西藏高原 环境变迁
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Change of bacterialcommunity in the Malan Ice Core and its relation toclimate and environment 被引量:10
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作者 XIANGShurong YAOTandong +5 位作者 ANLizhe lizhen WUGuangjiad WANGYouqing XUBaiqing WANGJunxia 《Chinese Science Bulletin》 SCIE EI CAS 2004年第17期1869-1875,共7页
In order to understand the relationship be- tween the community structure of bacteria in ice core and the past climate and environment, we initiated the study on the microorganisms in the three selected ice samples fr... In order to understand the relationship be- tween the community structure of bacteria in ice core and the past climate and environment, we initiated the study on the microorganisms in the three selected ice samples from the Malan ice core drilled from the Tibetan Plateau. The 16S ribosomal DNA (rDNA) molecules were directly amplified from the melt water samples, and three 16S rDNA clone li- braries were established. Among 94 positive clones, eleven clones with unique restriction pattern were used for partial sequence and compared with eight reported sequences from the same ice core. The phylotypes were divided into 5 groups: alpha, beta, gamma proteobacteria; CFB, and other eubac- teria group. Among them, there were many “typical Malan glacial bacteria” pertaining to psychrophilies and new bacte- ria found in the ice core. At a longer time scale, the concen- tration distribution of “typical Malan glacial bacteria” with depth showed negative correlation with temperature varia- tions and was coincident with dirty layer. It implied the in- fluence of temperature on the microbial record through im- pact on the concentrations of the “typical Malan glacial bac- teria”. In addition, the nutrition contained in ice was another important factor controlling the distribution of microbial population in ice core section. Moreover, the result displayed an apparent layer distribution of bacterial community in the ice core section, which reflected the microbial response to the past climatic and environmental conditions at the time of deposition. 展开更多
关键词 细菌群落结构 冰核 气候环境 微生物 西藏高原
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Microfossil assemblage characteristics in Core B10 and implication for paleoenvironmental evolution in the southern Yellow Sea 被引量:2
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作者 CHENGZhenbo SHIXuefa +3 位作者 CHENZhihua LIUDongsheng lizhen JUXiaohua 《Chinese Science Bulletin》 SCIE EI CAS 2003年第B06期49-56,共8页
Microfossil assemblage and pollen zone characteristics in Core B10 recorded the history of environmental changes in the southern Yellow Sea since Wiirm Subinterglaciation. Environmental variations reflected by these g... Microfossil assemblage and pollen zone characteristics in Core B10 recorded the history of environmental changes in the southern Yellow Sea since Wiirm Subinterglaciation. Environmental variations reflected by these glacial and interglacial sediments coincide with general characteristics of paleoenvironmental and sedimentary changes in the Yellow Sea. In the section of 550-520 cm, microfossil foraminifera have low abundance and diversity, and pollens are composed mainly of those of herbaceous vegetation, indicating climate change during Wiirm Subinterglaciation. In the section of 520-140 cm, the changes from a few microfossils to no microfossils reflect the sedimentary environment variation from coastal to terrestrial facies. Paleoclimate reflected by pollen also underwent the changes from conifer-broadleaf mixed forest to grassland, indicating the climate changes from temperate and cool type to warm and dry one. In the section of 140-0 cm, the general microfossil characteristics are the gradual increase in abundance with most species being neritic species, the major pollen being ligneous pollen and the rapid increase in small Hystrichosphaera content, which indicates that the air temperature increased and the sea level gradually rose. 展开更多
关键词 中国 黄海 环境变化 间冰期沉积物 有孔虫类化石 草本植物 地质气候 还平面
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