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Search Results: 1 - 10 of 314200 matches for " 张丽梅 "
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练习对大脑功能变化的影响及其意义
Practice Effect on the Changes of Brain Function and Its Implications
 [PDF]

杜萍, 陈雪,
Advances in Psychology (AP) , 2013, DOI: 10.12677/AP.2013.36051
Abstract: 近年来,大脑可塑性逐渐成为认知神经科学的一个重要研究方向。大脑可塑性分为结构可塑和功能可塑。本文介绍了练习引起的大脑功能激活的变化模式,分别是激活增加、激活减少以及激活的功能性重组,并分析了其影响因素,最后主要探讨了练习引起的大脑可塑性在临床上的治疗意义和教育实践意义。
 In recent years, brain plasticity in cognitive neuroscience has become an important research direction. There are structural and functional plasticity. This paper introduces patterns of experience-induced functional plasticity in brain and their determining factors. There are three patterns, including activation decreases, activation increases and reorganization of activation. Finally, the clinical and educational significance in brain plasticity after practice is mainly concluded.
数据库重叠直方图的设计

计算机系统应用 , 1996,
Abstract: 1.问题的提出在利用数据库管理系统Fo-chase设计信息处理系统时,经常要对系统中的某些数据指标进行统计分析,并以直方围的形式将结果送到显示器上或打印机上,供用户参考。以往大都采用一个数据指标输出一个直方图,对多个指标,就需要输出多个直方图。比如对某地区农业总产值增长情况进行统计,统计年限为第1992至第1995,产业为农业、林业、牧业、工业、渔业。其增减统计数据库AA.DBF如下:项目第1991第1992第1993第1994第1995种植业283.5078089560.00640.0098000林业300.17456.00573.00800001523.00牧业246.23678.90980…
GC-MS法测定苯胺法合成2-巯基苯并噻唑的废树脂
Determination of Composition in Spent Resins from the Aniline Process Adopted to the Synthesis 2-Mercaptobenzothiazole by Gas Chromatography-Mass Spectrometry
 [PDF]

张家, , 圣光, 赵建宏, 程相林, 王留成
Advances in Analytical Chemistry (AAC) , 2015, DOI: 10.12677/AAC.2015.51001
Abstract:
采用气相色谱–质谱法(GC-MS)对工业苯胺法合成2-巯基苯并噻唑(促进剂M)的副产废树脂进行了定性、定量测定。废树脂经四氢呋喃溶解后,采用GC-MS法测定,样品中分离的各种成分用NIST08谱库进行对照检索,采用面积归一法,计算出各化合物成分的相对含量。共鉴定了废树脂中的7种有机化合物,其中2-巯基苯并噻唑(M)和苯并噻唑(BT)的相对含量最高,分别为29.2%、31.1%。苯胺含量为6.2%,2,6-二叔丁基-4-甲基苯酚含量为17.4%,苯并噻唑衍生物含量共为14.2%,所鉴定的7种有机化合物峰面积之和占到总峰面积的98.1%。
The relative content and constituents of spent resins from the aniline process adopted to the syn-thesis 2-mercaptobenzothiazole (the Accelerator M) were analyzed by gas chromatography-mass spectrometry (GC-MS). After being dissolved in tetrahydrofuran, spent resins were measured by GC-MS and identified by NIST08. The relative content of each component was determined by area normalization. Total 7 constituents were identified in spent resins, wherein the relative contents of 2-mercaptobenzothiazole (M) and benzothiazole (BT) were the highest, accounting for 29.2% and 31.1% respectively. The contents of aniline, 2,6-Di-tert-butyl-4-methylphenol and benzothiazole derivative were 6.2%, 17.4% and 14.2%, taking 98.1% of the total peak area.
几种随机微分方程解的存在性与唯一性
The Existence and Uniqueness of Solution for Some Kinds of Stochastic Differential Equations
 [PDF]

陈晨, 引娣,
Advances in Applied Mathematics (AAM) , 2015, DOI: 10.12677/AAM.2015.41005
Abstract:

随机微分方程是把确定性现象和非确定性现象联系起来的一门比较新兴的学科分支[1]。研究随机微分方程的方法是从定性和定量两方面进行的,定性方面是研究解的存在性、唯一性和稳定性;而定量方面是研究求解的方法及求解过程的统计特性[2]。此篇论文首先介绍了随机微分方程的一些基本理论知识,对几种具体的随机微分方程做了一些定性的探讨,证明了几种随机微分方程解的存在性与唯一性。解的存在性的证明方法是先作变换,再借助伊藤公式,推导出解的表达式,从而也就证明了解的存在性。而解的唯一性证明过程中运用了Cauchy-Schwarz不等式和Lipschitz条件,还用到了Gronwall引理。
Stochastic differential equation (SDE) is a relatively new discipline branch linking the deterministic and non-deterministic phenomenon [1]. The method of studying SDE is proceeded from two aspects of qualitative and quantitative. Qualitative aspect is studying the existence, uniqueness and stability of the solution of SDE; and quantitative aspect is concerning the solving method and the statistical characteristics of the solving process [2]. In order to carry out the following proof, the thesis presents some basic theory knowledge about stochastic differential equation. By means of doing transforms, we obtain the expressions solution of SDE with the help of the formula \"\" , and thus we show the existence of the SDE. And finally, we prove the uniqueness of the solution of the SDE by utilizing the Cauchy-Schwarz inequality, the Lipschitz condition and the Gronwall’s lemma.

新疆阿勒泰地区低云量的气候变化及其与降水量的关系
Climate Change of Low Cloud Cover and Its Relationship with Precipitation in Aletai Area of XinJiang Province
 [PDF]

, 李建, 谢秀琴
Climate Change Research Letters (CCRL) , 2015, DOI: 10.12677/CCRL.2015.42007
Abstract:
选取1961~2010年新疆阿勒泰地区7站月平均低云量,月降水量,利用变差分析、Mann-Kendall、滑动t检验法、相关分析等方法来分析该地区低云量的变化及其与降水量的关系。结果表明:1) 大部分站低云量除冬季外,年及其它季节呈明显增多趋势,以1.1%~1.7%/10a的速率显著增加;2) 大部分站年、春、夏季低云量突变趋势显著,突变的时间为70年代中后期至80年代前期,冬季突变趋势不显著;3) 大部分站年低云量与春、夏、秋季低云量有很好的相关性,尤其和夏季的相关性最好。除冬季低云量外,春、夏、秋季低云量有较好的持续性。
By selecting average low cloud cover and monthly precipitation during 1961-2010 of 7 stations in Aletai Area of XinJiang Province, and using variation analysis, Mann-Kendall, sliding t-test method, correlation analysis and so on, the change of low cloud cover and its relationship with precipitation in Aletai Area of Xinjiang Province were analyzed. Our results showed that: 1) for most stations, low cloud cover significantly increased annually and seasonally except winter at the rate of 1.1% - 1.7%/decade; 2) for most stations, the mutation trend of low cloud cover in years, spring and summer was obvious and it occurred from the late 1970s to the early 1980s, while the trend was not significant in winter; 3) the annual low cloud cover of most stations had a good correlation with that of spring, summer and autumn, especially summer. In addition, in most stations, low cloud cover in spring, summer and autumn had good continuity.
贾家堡子铁矿8号矿体矿石选矿工艺研究
,
金属矿山 , 2011,
Abstract: 为了给大规模合理开发本钢集团贾家堡子铁矿8号矿体矿石资源提供技术依据,针对该矿石磁铁矿嵌布粒度微细的特点,采用大块干式磁选抛废—单一弱磁选和大块干式磁选抛废—弱磁选—反浮选两种工艺流程进行了选矿试验。结果表明:前者在-0.0308mm占90%的最终磨矿细度下,可获得铁品位为65.76%、回收率为75.93%的铁精矿;后者在-0.043mm占90%的最终磨矿细度下,可获得铁品位为65.47%、回收率为74.43%的铁精矿。两流程技术指标相近,采用哪种流程取决于技术经济比较。?
影响感觉寻求人格特质的生物遗传因素
,
心理科学进展 , 2007,
Abstract: ?综述了感觉寻求人格特质的生物遗传机制的相关研究。主要从3个方面对该问题进行了探讨:(1)单胺类物质与感觉寻求人格特质的关系;(2)激素对感觉寻求人格特质的影响;(3)感觉寻求人格特质的生物遗传性
2型糖尿病肾病大鼠肾小管间质中中期因子及肝细胞生长因子的表达
,冯凭
天津医药 , 2012,
Abstract: ?目的:探讨2型糖尿病肾病(dn)大鼠肾小管间质的病理变化及中期因子(mk)、肝细胞生长因子(hgf)表达变化及其相互关系.方法:60只sd大鼠随机分为正常对照组(a组,24只)、糖尿病组(b组,36只)。采用单侧肾切除+高糖高脂+stz复制t2dn模型。6周和12周时收集各组大鼠24小时尿测定24小时尿微量白蛋白,取血测空腹血糖,并计算肾重与体重的比值;用he染色及pasm染色方法观察肾小管及间质的病理变化;用免疫组化法检测肾小管间质中mk和hgf的表达变化,并进行半定量分析。结果:(1)与正常对照组比较,糖尿病组大鼠空腹血糖(fbg)、肾重与体重的比值(kw/bw)及尿微量白蛋白均明显升高(p<0.05)。(2)糖尿病组大鼠部分肾小管上皮细胞出现萎缩、脱落、空泡化,基底膜增厚及小管间质纤维化。(3)免疫组织化学方法提示糖尿病组mk和hgf在6周及12周末的表达均高于正常对照组(p<0.01);mk在12周末的表达高于6周末,有显著性差异(p<0.05);hgf在12周末的表达低于6周末,差异有统计学意义(p<0.05).(4)在糖尿病组,相关分析显示mk与hgf的表达成负相关(r=-0.525,p<0.01)。结论:mk和hgf在早期dn的肾小管间质中表达发生变化,提示两者可能共同参与了糖尿病肾病的发病。
高校图书馆学科馆员服务模式研究
,
图书情报工作 , 2008,
Abstract: ?对我国高校图书馆学科馆员服务模式的开展情况进行了调查与分析,并在此基础上探讨了学科馆员服务的主要工作内容。最后就如何发展我国高校图书馆的学科馆员服务提出了四点建议:一、不断提高学科馆员的素质及技能;二、加强学科馆员的组织和制度建设;三、建立统一的学科馆员服务平台;四、深化学科馆员的服务层次。
基于曲率模态差和小波变换的网架损伤识别
范 梦?,
河北科技大学学报 , 2014, DOI: 10.7535/hbkd.2014yx04013
Abstract: 采用一种基于曲率模态差和小波变换的损伤位置识别方法,对网架结构中常见的正放四角锥网架、两向正交正放网架、两向正交斜放网架、三向网架和蜂窝型三角锥网架进行了损伤识别,以结构损伤前后的曲率模态差作为小波变换的分析信号,对其进行db3连续和离散小波变换,确定杆件损伤位置。数值分析结果表明,在仅测得一阶模态的情况下,应用曲率模态差和小波变换相结合的方法可以对网架的单个损伤位置和多个损伤位置进行有效识别。
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