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Search Results: 1 - 10 of 83805 matches for " 彭方洪 "
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新疆鸽形山金矿床地质特征及成因探讨
陈刚,,,刘斌
地质论评 , 2013,
Abstract:
A STUDY ON INTER-INDIVIDUAL DIFFERENCES FOR THE DEVELOPMENT ABILITY OF ADEQUATE CONDITIONAL SYLLOGISTIC REASONING IN 12 YEAR-OLDS
12岁儿童充分条件假言推理能力发展的个体差异研究

Fang Fuxi,Tang Hong Liu Pengzhi,
富熹
,,

心理学报 , 2000,
Abstract: The purpose of the present study was to investigate the inter-individual differences for the developmental ability of adequate conditional syllogistic reasoning in 12 year-olds. The samples were randomly stratified according to the academic achievements of mathematics. The subjects were in total 40 school children divided into two groups : High ability group of math and general ability group of math with equal number of subjects.The subjects were individually tested with three types of tasks of syllogistic reasoning with verbal materials. Type 1 task referred an experimental context available to all school children; Type 2 task was based on a counterintuitive statement beyond concrete experiences; Type 3 task included abstractly a symbolized content. The results showed that four categories of subjects corresponding to four different levels of syllogistic reasoning were identified in terms of the statistical analysis for the verbal performances of the subjects. The subjects of the general ability group spread out on those four levels,which indicated that their ability of syllogistic reasoning was frequently constrained by the concrete contexts of the tasks, their pefformances could not free themselves from the perceptual experiences.However, the subjects of the high ability group were convergent to the highest level which was characterized by mature formal operational minking, the ability of assumed thinking in coordination with the ability of deductive reasoning were fully developed. The 'forms' liberated from the contexts. The ability of syllogistic reasoning correlated with the mathematical achievement and the levels of intelligence.
含湿率对多孔介质热导率测量准确性的影响
于明志,隋晓凤,晓峰,
化工学报 , 2008,
Abstract: 本文利用HotDisk热常数分析仪对不同含湿率时含湿沙的热导率进行测量研究,并对孔隙尺度水分形态、分布及演化过程进行了观察实验研究。研究发现,低含湿率(<25%)情况下,介质的有效热导率难以准确测得。低含湿时孔隙内水分主要以孤立液桥形式存在,测试过程中,贴近探头附近的水分由于受探头加热发生蒸发扩散而逐渐减少,导致探头周围试样构成持续发生变化,因而测量得到的热导率准确性较差。含湿率较高时,孔隙内水分相互联通,测试时水分蒸发扩散速度相对较慢,且存在毛细回流现象,探头周围试样构成维持恒定,因此可以准确获得热导率。
整体式桥台桥梁的动力试验研究
大文, 锦祥, 郭爱民, 德铭
中国公路学报 , 2004,
Abstract: ?研究了上坂大桥(中国最长的采用整体式桥台的无伸缩缝桥梁,简称为整体式桥台桥梁)在天然脉动荷载作用下的自振特性,得到关于该类桥梁自振特性的结论;采用结构分析软件ANSYS建立全桥的空间模型,计算该桥的自振特性,并与实测结果进行比较,结果表明:有限元模型具有较好的可靠性;实桥试验还测试了无障碍行车试验和跳车试验作用下桥梁的强迫振动特性,结果表明:该类桥梁的冲击系数值较大,而现行技术规范的取值值得商榷;此外该类桥梁具有较强的耗能能力,抗震性能较好。研究结果有助于对该类桥梁动力特性的认识和进一步开展无伸缩缝桥梁的抗震性能研究。
无伸缩缝桥梁的动力特性计算与试验研究
大文,锦祥,郭爱民,德铭
地震工程与工程振动 , 2005,
Abstract: 福建省永春县上坂大桥是目前我国修建桥长最大,采用整体式桥台的无伸缩缝桥梁。本文通过该桥的动力试验研究了该桥在天然脉动荷载作用下的自振特性,采用结构分析软件ANSYS建立全桥的空间模型,计算该桥的自振特性,与实测结果进行了分析比较。实桥试验还测试了无障碍行车试验和跳车试验这2种车辆激振作用下桥梁的强迫振动特性,并把实测的荷载冲击系数与新桥规的计算结果进行比较。研究结果有助于对该类桥梁动力特性的认识,有利于进一步开展无伸缩缝桥梁的抗震性能研究。
多角度热红外亮温值的模型拟合与应用
菁菁,刘强,柳钦火,李加,马红章,
红外与毫米波学报 , 2011,
Abstract: 通过二向性反射率分布函数(BRDF)核驱动模型对黑河试验多角度热红外机载数据的拟合,证明了核驱动模型具有热红外波段的外延能力,确定了适用于多角度热红外数据的最佳核函数组合.在热辐射方向性核系数组合因子与地表温度(LST)构成的特征空间中构建、提取了多角度热红外干旱指数(MTDI).在黑河各试验区,MTDI和温度植被干旱指数(TVDI)的反演结果非常相近(相关系数大于0.87),表明核驱动模型在热红外波段也是分析方向性辐射信息的有效模型.
未成熟树突状细胞对小鼠胶原诱导性关节炎的治疗作用
杨骁,,周建林,,陈森
- , 2016,
Abstract: 目的探讨未成熟树突状细胞(imDC)对小鼠胶原诱导性关节炎(CIA)的治疗作用及其机制。 方法分离、培养小鼠骨髓来源的单核细胞,经细胞因子和脂多糖(LPS)分别诱导为未成熟树突状细胞(imDC)和成熟树突状细胞(mDC),并采用流式细胞技术核对细胞表型。选取6~8周龄雌性BALB/c小鼠30只,鸡Ⅱ型胶原对所有小鼠初次免疫,于初次免疫后第6天按随机数字表法将小鼠分为imDC组、mDC组和磷酸盐缓冲液(PBS)组,每组10只,并分别经尾静脉输注imDC、mDC和PBS;初次免疫后第7天对3组小鼠行加强免疫。于加强免疫后第21天观察3组小鼠的关节变形程度,并检测其关节炎指数(AI)、血清抗炎因子IL-10、TGF-β水平以及脾脏CD4+CD25+调节性T细胞(Treg)比例。 结果经IL-4和GM-CSF诱导后,骨髓单核细胞CD80、CD86、MHC-Ⅱ的表达率分别为32.3%、25.6%、44.0%,经IL-4、GM-CSF和LPS诱导后,CD80、CD86、MHC-Ⅱ的表达率分别为91.5%、90.9%、94.2%,即imDC和mDC诱导分化成功。加强免疫后第21天,imDC组小鼠AI值为(7.32±1.63)分,显著优于同时间点的mDC组[(13.64±2.02)分]和PBS组[(12.78±1.96)分]。加强免疫后第21天,经ELISA检测,imDC组CIA小鼠血清IL-10和TGF-β以及脾脏CD4+CD25+Treg比例均显著高于同时间点的mDC组和PBS组,差异均有统计学意义(P<0.01)。 结论未成熟树突状细胞可有效抑制小鼠CIA的进展,其作用机制可能与未成熟树突状细胞可通过上调抗炎细胞因子的表达,刺激Treg细胞的增殖,从而诱导免疫耐受有关。
Objective To explore the therapeutic effects of immature dendritic cells on collagen-induced arthritis (CIA). MethodsMurine marrow-derived monocytes were isolated and cultivated with cytokines to generate immature dendritic cells (imDCs) and with lipopolysaccharide (LPS) to generate mature dendritic cells (mDCs). The differentiation and phenotypes were confirmed with flow cytometry. Murine models of rheumatoid arthritis (RA) were established with collagen II transfusion through the caudal vein. On day 6 after first immunization, subdermal injections of imDC, mDC or PBS were administered, and the mice were divided into three groups according to the injection they had received. On day 7 a second immunization was imposed to fortify CIA. Four weeks after the first immunization the severity of CIA was evaluated using an arthritis index (AI), serum levels of IL-10 and TGF-β using ELISA, as well as regulatory T cell (Treg) populations using flow cytometry. ResultsThe expression rates of CD80, CD86 and MHC-II by DCs induced with rrIL-4 and rrGM-CSF were 32.3%, 25.6% and 44.0%, and the rates by DCs induced with rrIL-4, rrGM-CSF and LPS were 91.5%, 90.9% and 94.2%, which identified the differentiation and phenotypes of the imDCs and mDCs. The aveage AI of the imDC group was 7.32±1.63, significantly lower than those of the mDC group (13.64±2.02) and the PBS group (12.78±1.96). The average serum concentrations of IL-10 and TGF-β in the imDC group were significantly higher than in the mDC and PBS groups. The proportion of Treg in the splenocytes of the imDC group was significantly higher than in the mDC and PBS groups. ConclusionCIA was markedly ameliorated by imDC, possibly through up-regulating the expression of anti-inflammatory cytokines like IL-10 and TGF-β and activating the Treg population, which could lead to immune
高效SnO2纳米片催化剂用于CO氧化
,,徐香兰,修忠,刘玥,蔡建信,王翔
催化学报 , 2015, DOI: 10.1016/S1872-2067(15)60926-3
Abstract: ?SnO2是一种具有丰富表面缺位氧的n型半导体,其晶格氧亦可还原.另外其熔点高达1630℃,具有较高的热稳定性能.在过去的几十年中,SnO2主要用作气敏材料.而其作为催化材料的性能,特别是用于大气污染治理则鲜见报道.在过去的几年中,本课题组系统研究了SnO2的催化化学,发现利用传统共沉淀法制备的SnO2纳米粉末,在焙烧温度高于500℃时,其比表面积通常低于20m2/g,因而限制了其氧化活性.在SnO2晶格中掺杂Fe、Cr、Mn、Ce和Ta等形成固溶体可有效提高其比表面积并产生更多的活性氧物种,因而其对CO和CH4的氧化活性及稳定性大幅度提高.本课题组近期研究结果表明,采用熔盐法制备的高纯SnO2纳米棒单晶比SnO2纳米颗粒和纳米微球等具有更优异的CO氧化活性,260℃即可完全氧化CO.且在240-260℃狭窄温度区间发生转化率突跃,表现出类似贵金属的催化行为.值得指出的是,SnO2纳米棒的比表面积(1m2/g)远低于其他几种形貌的材料,且无活泼氧存在.但研究表明SnO2纳米棒具有优先暴露的(110)活泼晶面,是导致其活性优良的主要原因.另外,我们采用简单共沉淀法成功制备了高比表面介孔Cu-Sn复合氧化物纳米片(196m2/g),其在140℃即可将CO完全氧化,且具有优良的抗水失活性能.因此,SnO2的形貌是影响其催化活性的主要因素之一,但迄今未见较系统深入的研究.在上述工作基础上,本文通过水热法,不添加任何有机模板剂,成功制备了厚度约10nm的介孔SnO2纳米片和纳米棒及纳米颗粒混合物样品;采用常规共沉淀法制备了SnO2纳米颗粒.并将以上三种不同形貌的SnO2纳米材料用于CO氧化.利用SEM、XRD、N2吸附-脱附、H2-TPR和XPS探讨了不同形貌SnO2催化剂的体相结构和表面性质及其对催化性能的影响.与SnO2纳米颗粒相比,介孔SnO2纳米片具有高的比表面积、孔体积及更活泼的氧中心,因此后者CO氧化活性远高于前者.在空速18000mL/(g·h)时,SnO2纳米片在260℃即可完全氧化CO.而SnO2纳米颗粒的CO完全氧化温度高于360℃.SnO2纳米棒和纳米颗粒的混合样品虽然其比表面积和孔体积及表面活性氧的活性仅略高于SnO2纳米颗粒,但XRD定量结果表明,其具有更多的暴露(110)活泼晶面,因而活性也高于SnO2纳米颗粒.SnO2纳米片催化剂的寿命及抗水性能测试结果表明,该催化剂具有良好的稳定性,且水蒸气仅对其活性产生可恢复的影响.进一步优化其性能,SnO2纳米片有可能用于实际汽车尾气状况下的CO催化清除.
新型海洋微生物β-葡萄糖苷酶基因的克隆、表达及重组酶性质
房伟?,泽民?,刘娟娟?,宇植?,惠?,张学成?,孙宝林?,肖亚中?
生物工程学报 , 2009,
Abstract: 通过功能筛选方法,从中国南海海洋表层海水微生物元基因组文库筛选得到了6个β-葡萄糖苷酶阳性克隆。对其中的一个阳性克隆psb47b2进一步亚克隆和序列分析,获得一新型β-葡萄糖苷酶基因(命名为bgl1b)开放阅读框。以pet22b(+)为载体、escherichiacolibl21(de3)为宿主菌,bgl1b被高效活性重组表达。通过ni-nta亲和层析柱纯化了重组bgl1b(rbgl1b)。纯化的rbgl1b催化pnpg水解反应的最适ph为6.5,最适温度为40oc。在最适反应条件下,rbgl1b水解pnpg的活性达到39.7u/mg,km和vmax分别为0.288mmol/l、36.9μmol/min。纤维二糖是rbgl1b的有效作用底物,其km和vmax分别为0.173mmol/l、35μmol/min。但rbgl1b不能催化转化蔗糖、乳糖、麦芽糖以及cmc。rbgl1b催化pnpg的水解反应对高浓度的na+有较好的耐受性,而低浓度的ca2+、mn2+对该酶活有一定促进作用。不同于许多来源于真菌的酸性β-葡萄糖苷酶,rbgl1b在ph7.0到9.0范围内具有比较高的酶活力并具有较好的稳定性。
道德情绪对道德判断能力的影响
The Effect of Moral Emotion on Moral Judgment Capacity
 [PDF]

周树芝,
Advances in Psychology (AP) , 2014, DOI: 10.12677/AP.2014.47126
Abstract:
本实验进行了两次测试,前测选取了网络热议或大学生生活中较典型的道德故事,对其进行前后测后,筛选出其中能诱发相应情绪的道德故事。正式实验中,情绪启动之后,测量被试的情绪状态,运用MJT对大学生进行道德判断能力测验。实验发现:积极情绪条件下道德判断能力显著低于控制组,控制组显著低于消极情绪组;不同的积极情绪条件下道德判断能力差异不显著;不同的消极情绪条件下差异不显著;男性的显著大于女性;大四的明显大于大一,其他年级之间差异不显著。
This study conducted two tests. The pretest selected apologue popular on the Internat and typical in college students’ life. After pre-post test, the apologue which could induce corresponding emo- tions was screened out. In the formal test, after affective priming, subjects’ emotional state was measured, and MJT was used to test the moral judgment capacity of college students. It was found that the moral judgment capacity in the positive mood condition was significantly lower than that in the control group, and the moral judgment capacity in the control group was significantly lower than that in the negative mood group; the differences of the moral judgment capacity were not significant in different positive emotional conditions and also in different negative emotional conditions; the differences of the moral judgment capacity of males were more significant than those of females; the differences of senior students were more significant than those of freshmen, and were not significant in other grades.
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