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Search Results: 1 - 10 of 328395 matches for " 王晏鹏() "
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公路主枢纽客货站场规模确定方法
刘伟华,,
重庆交通大学学报(自然科学版) , 2002,
Abstract: :?公路枢纽规划站场布局中,站场规模的确定是很重要的一步,它涉及到整个枢纽建设的投资和运营效果的好坏。针对以往的枢纽布局规模确定的不足,笔者提出了“五因素法”来确定规模,全面考虑了客货运输的特点和枢纽规划的要求,并且介绍其在一个具体枢纽规划实例中的应用,增加了规模确定的准确性和可靠性
不同平面心理旋转的角色效应
游旭群,,碧华
心理学报 , 2007,
Abstract: ?本研究采用实验方法,分别在水平面和冠状面内对第一人称角色和第三人称角色心理旋转进行对比性研究。实验结果表明:空间表征转换的角色方式对心理旋转产生显著影响,第三人称角色心理旋转易于第一人称角色心理旋转,即存在心理旋转的角色效应;心理旋转的角色效应并不是在特定旋转条件下才出现的,具有更大的普遍性
反向物流系统的研究现状与展望
吴刚,,陈兰芳,煜洲
科技进步与对策 , 2006,
Abstract: 随着资源、环境与社会经济发展之间的矛盾日益突出,反向物流越来越受到广泛关注。从研究的问题和研究方法两个方面回顾了国内外与反向物流有关的研究成果,尤其是对反向物流网络结构的研究。在对现有研究进行分析和评述的基础上,指出了反向物流研究的可能趋势。反向物流综述反向物流网络
采用吸宫和电凝方法建立小鼠子宫内膜损伤模型的比较
(),黄琼晓,徐盛,舒静,()
- , 2017, DOI: 10.3785/j.issn.1008-9292.2017.04.11
Abstract: 目的:比较吸宫和电凝两种方法造成小鼠子宫内膜损伤模型的特点。方法:吸宫组采用自制20 G针头插入ICR小鼠一侧宫腔,以0.05 MPa负压全面吸宫1周;电凝组采用自制单极电针以0.5 W功率迅速电凝损伤子宫腔。均以对侧子宫为对照,对照仅插入针头或电针后退出。比较平均手术时间、术后单层子宫内膜厚度、妊娠4 d子宫内膜容受性相关因子的表达情况、妊娠10 d胎鼠数差别。其中HE染色观察子宫内膜组织形态学改变,蛋白质印迹法检测子宫内膜白血病抑制因子和抑瘤素M的表达。结果:吸宫组平均手术时间(10.2±1.3)min,电凝组平均手术时间(10.1±1.5)min,差异无统计学意义(P>0.05)。吸宫组损伤侧宫腔无封闭现象,电凝组有2只小鼠存在宫腔局部封闭、远段积水。损伤侧子宫内膜厚度吸宫组(96.1±13.2)μm,电凝组(88.9±16.8)μm,均比对照侧子宫减小(均P<0.01)。损伤侧子宫内膜白血病抑制因子和抑瘤素M的表达吸宫组高于电凝组,但两组损伤侧表达均低于对照侧(均P<0.01)。吸宫组损伤侧平均胎鼠数目(4.2±0.9)只,电凝组损伤侧平均胎鼠数目(3.9±1.7)只,均较对照侧下降(均P<0.01)。电凝组损伤侧还可见胎鼠死亡现象。结论:吸宫和电凝均可造成小鼠子宫内膜损伤,导致子宫内膜容受性下降和生育力受损。电凝损伤更符合重度宫腔粘连特征,而吸宫损伤可能更适用于轻中度宫腔粘连研究。
Abstract: Objective: To establish mouse endometrial injury model by curettage or coagulation. Methods: Female ICR mice were randomly allocated into 2 groups: in curettage group, a blunt 20G needle was inserted in one uterine horn with 0.05 megapascals negative pressure; in coagulation group, one uterine horn was coagulated using a monopolar electric needle with 0.5 watts power. In both groups the contra-lateral uterine horn was used as control. The morphological changes and thickness of endometrium were evaluated 1 week after operation. The endometrial samples were taken on d4 of pregnancy, and the expressions of endometrial receptivity-related cytokines were examined. The number of implanted embryos on each side of uterus was calculated on d10 of pregnancy. Results: There was no difference in operation time between 2 groups. In both groups, the endometrial glands and stroma were significantly reduced, and the endometrial thickness was also significantly decreased on injury side compared to contra-lateral horn. However, local injury was more severe in coagulation group, uterine obliteration and hydrops were developed in 2 mice of coagulation group, and none in curettage group. The expressions of leukemia inhibitory factor (LIF) and oncostatin M (OSM) were significantly reduced on injured side in both groups compared to opposite side; however, the expression of LIF and OSM in curettage group was higher than that in coagulation group. The numbers of implanted embryos were decreased in both groups on injured side compared to opposite side, and fetal death was only observed in coagulation group. Conclusion: Both curettage and coagulation can make injury on mouse endometrium, impair endometrial receptivity and reduce fertility. Curettage can cause moderate injury, and coagulation may lead to more severe injury. Key words: Electrocoagulation Abortion, induced/methods Uterine diseases Adhesions Endometrium Embryo implantation Disease models,
载钯树脂对偶氮类染料的吸附降解及其产物对发光菌的毒性暴露试验
冯丽,葛小,晓敏,东升,汤鸿霄
生态毒理学报 , 2011,
Abstract: 合成了表面负载金属钯的聚丙烯醛异烟酰腙树脂后,通过Q67发光菌的毒性暴露实验研究了该树脂材料对直接大红、直接天蓝和桃红等3种水溶性偶氮染料的催化降解效果及其在降解过程中对发光菌的生物毒性变化情况,并对降解结果进行了气相色谱-质谱(GC-MS)分析。实验结果表明: 载钯树脂对直接大红、直接天蓝和桃红等偶氮染料具有良好的吸附降解脱色能力。其中,载钯树脂对直接天蓝和桃红的去除率可达95%,其对发光菌的急性生物毒性在降解过程中呈先减小后增大的变化规律。在降解反应后,仍可检测到萘环及其他小分子,这说明载钯树脂对发光菌的急性生物毒性可能是由于小分子降解产物具有一定的生物毒性效应所致。
Perspective Effect of Mental Rotation in Different Planes
不同平面心理旋转的角色效应

You Xuqun,Wang Peng,Yan Bihua,
游旭群
,,碧华

心理学报 , 2007,
Abstract: Introduction The human visual system can represent an object's spatial structure using either a first-person perspective or a third-person perspective. It can also utilize either a first-person or a third-person processing mode to perform mental rotation. Since Shepard and colleagues' classical study, experiments over the next 30 years did much to elucidate the basic nature of mental rotation. However, most of the studies only concern about first-person rotation. Third-person rotation has been neglected in the field of mental exploration. Thus, the present study aimed to compare the relative difficulty of first- and third-person rotation of an imagined environment. The hypothesis was that third-person rotation would be easier than first-person rotation in the transverse and coronal planes. Method Two experiments were conducted, each comparing first- and third-person rotation in the transverse plane (Experiment 1) and coronal plane (Experiment 2), respectively. Seventy six right-handed undergraduates (aged between 19 and 21) took part in the experiments. Both of the experiments used a 2 (perspective: first- vs. third-person rotation) x 4 (angle) mixed design. Each participant performed either first- or third-person rotation. In the first-person task, participants were asked to imagine themselves rotating in the center of a four-object array to a certain angle and were then asked to guess the position of the object relative to their imagined orientation (Experiment 1: right, left, front, or back; Experiment 2: top, bottom, right, left). In the third-person task, participants were asked to imagine another person rotating in the center of a four-object array ahead of them to a certain angle and were then asked to guess the position of the object relative to that imagined person's orientation after rotation (Experiment 1: right, left, front, or back; Experiment 2: top, bottom, right, left). Reaction time (measured from the end of the question to the onset of the participants' response) and number of errors were recorded and analyzed. Results and Conclusion The results confirmed our hypothesis. In experiment 1, the third-person task was performed with shorter reaction time and fewer errors than the first-person task in the transverse plane. ANOVA revealed the main effect of perspective and angle, as well as a significant perspective-by-angle interaction. That is, RTs for the first- and third-person rotation were not different at 0 , but the overall latency of the response in the first-person rotation was greater than that in the third-person rotation at 90 , 180 , and 270 . The results of Experiment 2 were similar to that of Experiment 1. When compared to the first-person rotation, there were reduced RTs and errors for the third-person rotation in the coronal plane in which one cannot naturally locomote. The present study reveals that there is an advantage of third-person rotation over first-person rotation. Third-person rotation is easier than first-p
钙钛矿型La1-xCaxMnO3 δ催化剂制备及其甲烷催化燃烧性能研究
耀宗,郭谨玮,陈亚中,,
分子催化 , 2015,
Abstract: 采用柠檬酸络合法制备了系列La1-xCaxMnO3+δ(x=0, 0.03, 0.05, 0.07, 0.1, 0.15, 0.2)催化剂,采用低温N2物理吸附,氢程序升温还原(H2-TPR)、氧程序升温脱附(O2-TPD),X-射线衍射(XRD)和X-射线光电子能谱(XPS)研究了其物理化学性质,并考察了甲烷催化燃烧活性。结果表明,当Ca摩尔掺杂量为0.1时,催化活性最好。XRD和BET表征结果表明Ca可以进入钙钛矿结构中,Ca掺杂对催化剂的比表面积无显著影响。H2-TPR 和XPS表征结果表明Ca掺杂增加了Mn4+的含量。O2-TPD表征结果表明适量Ca掺杂可以降低晶格氧脱出温度。Mn4+具有较强氧化性,因此提高了催化活性,但随着Ca掺杂量增加,催化剂表面吸附氧含量有所减少,表明气相中氧难以迅速补充消耗的晶格氧,Ca掺杂量继续增加又会使催化活性有所下降。依据反应机理,Ca掺杂一方面可以促进Mn4+含量增加,有利于催化活性;另一方面会使催化剂表面吸附氧含量有所下降,降低了催化活性。
排口比对污泥淤砂分离器分离效能的影响
,吉芳英,,范剑平,颜达超
环境工程学报 , 2014,
Abstract: 污泥淤砂分离器是一种能够使活性污泥中污泥有机质与淤砂分离的设备。为了实现污泥淤砂分离器的结构优化,重点探讨了污泥淤砂分离器最重要的结构参数-排口比K(底流口直径Du与溢流口直径Do之比)对污泥淤砂分离器分离效能的影响。实验结果表明,在排口比从0.32增加到1.0的过程中,分离器处理能力Qi基本保持不变,分流比S、分离效率η和底流污泥ρ(MLVSS)/ρ(MLSS)分别从0.084、24.7%和0.21增加到0.338、41.1%和0.33.4;污泥有机质富集率FMLVSS和淤砂富集率FMLISS分别从1.95和1.35减小到1.22和1.12。富集除砂所需要的K和分离器获得较高的除砂效率η时所需K不一致。污泥淤砂分离器排口比K设计为0.4~0.6时,能够获得较高的分离效率,并实现淤砂的富集排放。
载钯螯合树脂的制备、表征及其降解多溴联苯醚的初步研究
侯春凤,周岩梅,葛小,晓敏,东升
环境工程学报 , 2009,
Abstract: 以聚丙烯醛-异烟酰腙螯合树脂为高分子载体,利用其活性基团对钯的选择性富集分离性能,将金属元素钯键合到高分子载体上,制备一种含钯树脂材料(树脂1),并进一步原位还原得到还原态的载钯树脂(树脂2)。利用红外光谱、扫描电镜和X射线衍射等对以上2种含钯树脂材料进行了分析表征,并考察了它们对持久性有机污染物(POPs)多溴联苯醚(PBDEs)的脱溴降解性能。结果表明,2种树脂对BDE209均有降解活性,其中树脂1的降解性能比树脂2的降解性能要高,树脂中钯的氧化形态可能对BDE209的催化降解起主要作用。
基于氦泡与位错密度演化的老化δ-pu静力学本构模型
顺坪,余勇,沪毅,赵丰
物理化学学报 , 2015,
Abstract: δ-pu材料由于钚元素α衰变发生自辐照老化,随着老化时间增加,材料微结构和宏观力学性质发生变化.氦泡作为自辐照的主要产物,通过阻碍位错运动实现对δ-pu力学性质的影响.文中首先通过钚材料级联衰变规律建立氦泡体积分数与老化时间的关系,然后将氦泡对位错运动临界剪切应力的影响和氦泡长大规律引入本构方程,获得基于位错密度演化的δ-pu静力学本构方程组.拟合实验数据得到本构模型参数.最后,通过模型计算获得不同老化时间下δ-pu的应力应变关系.
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