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Search Results: 1 - 10 of 42519 matches for " 曹璐婷 "
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大学生逃课现象的原因分析及相关对策
The Analysis of Truancy Phenomenon of Undergraduates and Related Measures
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Advances in Education (AE) , 2011, DOI: 10.12677/ae.2011.11002
Abstract:

关于大学生的逃课问题近年来已经成为社会的热点话题之一,这种现象的产生是由多方面的原因造成的,不仅仅在于大学生自身的因素,而且存在社会形势,及其学校和教师方面的原因。深挖大学生逃课现象的深层次原因,并综合分析这种现象背后的多方面因素,通过从学生心态、教师队伍建设、学校相关体制的改革等方面着手,积极努力去解决并减少大学生逃课现象的发生。
In recently years, the truancy phenomenon of undergraduates has become a hot topic in whole society. The phenomenon is caused by many reasons, which include not only the factors of university student, but also the social landscape, university and teachers. To explore the deep reasons of the truancy phenomenon, we should comprehensive analyze numerous factors behind this phenomenon. According to observing undergraduates’ mind, strengthening the contingent of teachers and reforming university’ system, we need work together to reduce the rate of truancy phenomenon of undergraduates.

六味地黄汤对2型糖尿病大鼠环磷酸腺苷及脂肪磷酸二酯酶3b的影响
肖子曾,曾呈茜,戴冰,吴沁璇,,杨梦琳,张嘉倪
中国中医药信息杂志 , 2015, DOI: 10.3969/j.issn.1005-5304.2015.08.020
Abstract: 目的观察六味地黄汤对2型糖尿病胰岛素抵抗大鼠环磷酸腺苷(camp)及脂肪组织磷酸二酯酶3b(pde3b)的影响,探讨其改善2型糖尿病的作用机制。方法将80只sd大鼠随机分为空白组和造模组,造模组采用高脂高糖喂养加腹腔注射stz造模。将成模大鼠分为模型组、罗格列酮组、六味地黄汤组。各给药组每日给予相应药物灌胃,模型组和空白组给予等量生理盐水,连续30d。常规检测大鼠空腹血糖(fbg),elisa检测大鼠血清camp和胰岛素(ins)水平,westernblot检测脂肪组织pde3b蛋白表达,实时荧光定量pcr检测脂肪组织pde3bmrna表达。结果与模型组比较,各给药组大鼠fbg、fins水平降低(p<0.05,p<0.01);六味地黄汤组大鼠脂肪组织pde3b蛋白及mrna表达升高、血清camp浓度降低(p<0.01)。结论六味地黄汤可上调脂肪组织pde3b因子表达,降低camp浓度,这可能是其改善2型糖尿病大鼠胰岛素抵抗的作用机制之一。
国外城市公共体育场馆服务大众体育发展经验及对我国的启示
Development Experience of Overseas Public Sports Facilities and Its Enlightenment to China


- , 2016, DOI: 10.19582/j.cnki.11-3785/g8.2016.10.006
Abstract: 摘要:采用文献和比较分析等研究方法,对国外城市公共体育场馆服务大众体育经验及对我国的借鉴进行了研究。研究认为:法国的巴黎、英国的伦敦、日本的东京、新加坡和美国的纽约城市公共体育场馆在服务大众体育发展的过程中,不断探索与创新出成功的发展模式,是国外城市公共体育场馆服务大众体育发展较为成功的典型案例。其中在注重奥运体育场馆赛后服务大众体育的发展和城市公共体育场馆基础设施生态化建设及城市公共体育场馆建设向社区方向发展的经验,对我国城市公共体育场馆服务于全民健身的开展是相当有助益的。据此,根据我国城市公共体育场馆建设的特殊国情,在借鉴国外城市公共体育场馆服务大众体育发展成功经验的基础上,探索出适合我国城市公共体育场馆服务全民健身发展的路径,即,创新大型体育赛事场馆赛后利用多功能综合运行模式,科学规划城市公共体育场馆建设的布局,加大对城市公共体育场馆建设服务全民健身开展的财政扶持力度,构建城市公共体育场馆服务全民健身开展的多功能运行模式和城市公共体育场馆服务全民健身评价指标体系发展等,为我国城市公共体育场馆建设促进全民健身公共服务体系的构建提供理论依据。
Abstract: This study analyzed the experience of overseas public sports facilities and its enlightenment to China by the methods of literature review and comparative analysis. The result showed that public stadiums of Paris, London, Tokyo, Singapore City and New York City explored a successful model of development and innovation in the development process of mass sports service. They are the typical successful cases. Their experiences on Olympic Games Stadium service after game to mass sports, urban public infrastructure ecological construction to community, are useful to China urban public sports stadiums service for national fitness. Therefore, this study put forward a suitable way for China urban public sports stadiums service for national fitness according to the special situation of public sports stadiums construction in China and their experiences. That is innovating multifunctional integrated operation mode, designing public stadium construction scientifically, adding fiscal support, constructing multi function operation mode, and setting up evaluation index system. It hoped to provide a theoretical reference for constructing the system of urban public stadium promoting national fitness
兰坪盆地多金属矿床硫同位素特征及意义
Characteristics of Sulfur Isotopes in Polymentallic Deposits in Lanping Basin
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刘远超, 刘腾,
Open Journal of Nature Science (OJNS) , 2016, DOI: 10.12677/OJNS.2016.41008
Abstract:
兰坪盆地内产有金顶铅锌矿、白秧坪银铜多金属矿床、盆地西缘脉状铜多金属矿床,为查明成矿流体的来源,对这些矿床中不同矿物中的硫同位素数据进行了分析和对比研究。金顶铅锌矿和白秧坪银铜多金属矿西矿带中硫化物的特征显示硫源为细菌还原硫酸盐及部分的有机热化学还原作用将成矿热液中的硫酸盐转化而来;白秧坪银铜多金属矿东矿带和盆地西缘脉状铜矿主要为有机热化学还原作用将热液中的硫酸盐转化为还原性硫。
Jinding lead-zinc deposit, Baiyangping silver-copper polymetallic deposit and the vein-type Cu- polymetallic deposits on the western border of the Lanping Basin are located in Lanping basin. In order to trace source of ore-fluiding, the data of sulfur isotope of different mineral in these deposits were selected to analyze. The characteristic of sulphide in Jinding lead-zinc deposit and the eastern ore-belt of Baiyangping silver-copper polymetallic deposit show that sulfur source is from bacterial sulphate reduction and partly thermochemical sulphate reduction. The characteristic of sulphide in the eastern ore-belt of Baiyangping silver-copper polymetallic deposit and the vein- type Cu-polymetallic deposits on the western border of the Lanping Basi show that sulfur source is from thermochemical sulphate reduction.
内蒙古石匠山矿区矿石特征及银赋存状态
Analysis on Ore Composition and the Occurring States of Ag of Shijiangshan Mining Area, Inner Mongolia
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程书, 建劲
Open Journal of Nature Science (OJNS) , 2016, DOI: 10.12677/OJNS.2016.43036
Abstract:
石匠山多金属矿床为热液脉状裂隙充填矿床,其伴生银品位较高,由于基础地质工作缺乏,银赋存形式未知,导致银的综合回收利用存在一定困难。因此,矿床基础地质及银赋存形态研究对于下一阶段勘探和银的回收具有十分重要的指示意义。本文在野外调研的基础上,采集了8个矿石样品,通过偏反光显微镜观察和电子探针分析,研究了矿石中金属硫化物矿物特征以及银的赋存形式。石匠山矿区深部矿石以方铅矿、闪锌矿、毒砂、黄铜矿、黄铁矿等为主要硫化物而矿石中的银大部分以不可见银形式存在。含银矿物为铁锑银黝铜矿,主要呈半自形包裹体存在于黄铁矿等硫化物内部,粒径小于1 μm。大多数方铅矿中含银超过0.08%,含量从晶粒边部向内部逐渐降低,表现为晶格银形式。
Although the average grade of silver is high in Shijiangshan mining area, lacking basic geological works and states of Ag in the ore, it is really difficult to recover Ag in the ore. In order to get rid of this situation, necessary basic geological researches are of great importance for the next stage exploration to recover Ag. This paper is based on field investigation, data of eight deep ore samples analyzed by partial reflective microscope and EPMA, aiming to discuss features of sulfide minerals, states of Ag and the genetic type of this mineral deposit. The experiment result shows that deep ore samples are composed of galena, sphalerite, arsenopyrite, chalcopyrite and pyrite as its main occurring states. More importantly, further study shows that there are two forms of silver in the samples belonged to invisible silver, which are the silver of microscopic inclusions and in the form of isomorphism. Specifically, microscopic inclusion is tetrahedritedyscrasite with hypidiomorphic granular texture in pyrite and the other form silver exists mainly in the form of isomorphism in the galena with a tendency that silver content reduces from the edge to the interior. The size of the inclusion is less than 1μm, and the content of silver in galena is over 0.08 percent.
研发投入对我国制造类企业绩效影响研究
,张婉
科技进步与对策 , 2013, DOI: 10.6049/kjjbydc.2013100573
Abstract: 以2009-2012年我国制造业上市公司为样本,考察研发投入对制造类企业绩效的影响。实证结果发现,研发投入与制造类企业当期绩效之间呈显著正相关关系,其中研发资金对当期绩效的贡献程度明显大于研发人员贡献程度;此外,研发资金投入对制造类企业绩效的正相关影响存在滞后性,滞后期为两年且影响程度在滞后一期达到最大值;最后,从增加长期性资本投入、加强基础性研发及整合科研人力资源等方面提出了政策建议。研发人员投入研发资金投入制造行业企业绩效
沟通力时代注意力模式的变化——以虚拟社区“宝宝树”为例
王菲,
国际新闻界 , 2014,
Abstract: 随着网络虚拟社区的兴起,有学者认为,注意力经济时代,用户在创造注意力的同时,还在创造沟通力,沟通力是注意力模式的外在表现。因此,研究沟通力也是研究注意力模式的方法之一。并将这个日益由互联网技术统治的时代称为沟通力时代。本文以虚拟社区宝宝树为例,研究了该社区的沟通力情况,以及沟通带来的注意力在生产、加工、分配、交换和消费模式上的变化。研究结果认为,在沟通力时代的虚拟社区中,注意力生产呈现差异化趋势,这体现在人们对产品需求随年龄、地区等因素呈现差异。注意力加工细化和个性化,人们倾向传播和关注个性信息,以获得别人的关注。注意力主要分配在日常渠道论坛中,游戏渠道是注意力停留时间最长的渠道。注意力在交换过程中日益呈现出用户-沟通-商家的反流通方向,即用户在沟通中提出需求,商家再进行满足的生产营销过程。
磁性多壁碳纳米管净化技术快速测定水中多种抗生素残留
Quick Determination of Antibiotics Residues in Water Samples by Magnetic Multiwalled Carbon Nanotubes Cleaning Technology
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, 施元旭, 郑军科,
Advances in Analytical Chemistry (AAC) , 2016, DOI: 10.12677/AAC.2016.64015
Abstract:
采用磁性多壁碳纳米管-超高效液相色谱/质谱/质谱(UPLC/MS/MS)技术测定水样中23种抗生素残留量。水样基质中的23种抗生素药物先采用磁性多壁碳纳米管(MWCNTs)富集和净化,再用5%的氨水甲醇溶液脱附,23种化合物以CORTECSTM C18+色谱柱分离,甲醇和0.1%的甲酸水溶液作为流动相,采用电喷雾正离子(ESI+)和多反应监测模式(MRM)分析,外标法定量。23种抗生素在0.5~50 μg/L的浓度范围内线性相关系数均大于0.99,检出限为0.01 μg/L,定量限为0.03 μg/L。在0.05、0.5、10 μg/L不同浓度水平下,23种抗生素的平均回收率在87.5%~105.8%之间,相对标准偏差在0.3%~4.2%之间。由于该技术简便、快速、灵敏度高,适用于水中23种抗生素残留的快速测定。
A method was established for determining 23 antibiotics residues in water samples by magnetic multiwalled carbon nanotubes and ultra performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS). The 23 antibiotics in water samples were first enriched and cleaned up by magnetic multiwalled carbon nanotubes, and then eluted with ammonium hy-droxide-methanol (5:95, v/v). The target antibiotics were separated by Waters CORTECSTM C18+ column using methanol and 0.1% formate in water as mobile phases. The analytes were detected by positive electrospray ionization with multiple reaction monitoring. External standard method was used to determine the quantity. In the linear range of 0.5~50 μg/L, the correlation coefficients of 23 antibiotics were greater than 0.99, the limit of detection (LOD) was 0.01 μg/L, and the limit of quantitation (LOQ) was 0.03 μg/L. The mean recoveries at the three spiked levels of 0.05, 0.5, 10 μg/L were 87.5%~105.8%. The relative standard deviation (RSD) was 0.3%~4.2%. The simplicity, sensitivity and good precision of the method made it be well suitable for quick determination of the 23 antibiotics residues in water samples.
兰坪盆地金顶铅锌矿床砂岩型矿石的沉积特征与粒度特征
Depositional Features and Grain Size Characteristics of Sandstone-Type Ore of Jinding Pb-Zn Deposit in Lanping Basin
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刘腾, 何珍明, 刘远超,
Open Journal of Nature Science (OJNS) , 2015, DOI: 10.12677/OJNS.2015.34025
Abstract:
金顶超大型铅锌矿床主要由角砾岩型和砂岩型两类矿体组成,但容矿岩石的成因及归属等问题尚不明确。利用粒度资料进行沉积物的粒度结构分析,可以有效地判定沉积物搬运方式、判别水动力条件、区分沉积环境类型,研究沉积物的成因机制。本文通过绘制粒度概率累计曲线图、C-M图等图件,详细研究了砂岩型矿石的粒度特征,确定了其沉积水动力类型,结合砂岩型矿体的构造背景、矿石显微构造等特征,探讨了砂岩型矿石的成因,研究表明砂岩型矿石属于细砂-粉砂岩,平均粒径为1.526Φ,正偏态或很正偏态,物质来源为河砂;从萨胡环境判别公式以及C-M图解中,可以看出研究区砂岩以重力流沉积为主;认为它是碎屑物质以重力流方式搬运并在快速水流作用下与底部物质混合、再悬浮、沉积而形成。
Jinding super-large Pb-Zn deposit is mainly composed of breccias-type and sandstone-type ore body, but the genesis and ownership of ore-hosted rocks are still unclear. The utilization of grain- size data to analyze the structure characteristics of the sediment grains can effectively determine the transport mode of sediments, judge the hydrodynamic conditions, distinguish the sedimentary environments, and analyze the genetic mechanism of sediments. Based on the probability cumulative grain-size curves and C - M graph, the authors studied in detail the grain-size characteristics of sandstone-type ore, and defined its sedimentary hydrodynamic type, then combined with the tectonic background of the sandstone-type ore body and ore microscopic structure characteristics, the genesis of sandstone-type ore was discussed. The result shows that the sandstone-type ore belongs to the fine sandstone-siltstone, the average particle size of 1.526Φ, positive skewness or very positive skewness, and material source for river sand. From Sahu environment discriminant and C - M graph, it can be seen that the sandstone in the study area is given priority to gravity flow deposits. The result shows that the sandstone is formed by fragmentary material handling in gravity flow and mixed with the bottom material, resuspension and sedimentary under the action of rapidly water.
基于参数评估的可调节式分组流分类算法
,龚向阳
北京邮电大学学报 , 2007, DOI: 10.13190/jbupt.200704.60.caot
Abstract: 基于决策树的启发式流分类算法目标是建立结点数目尽可能少,树深度尽可能小的数据结构,从而获得较优的时空性能。本文提出的基于参数评估的可调节式流分类算法(PEAParameterEvaluationAdjustablealgorithm)一方面沿袭目前主流的决策树类流分类算法思想,一方面引入性能参数的概念,并采取调节参数权值的方式获得性能最佳的数据结构。大量测试结果表明,相同条件下本算法对比同类算法能够获得更优的性能结果。
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