oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 16 )

2018 ( 462 )

2017 ( 466 )

2016 ( 477 )

Custom range...

Search Results: 1 - 10 of 20497 matches for " 崔赛赛 "
All listed articles are free for downloading (OA Articles)
Page 1 /20497
Display every page Item
变压器冷却器带电水冲洗与空气冲洗性能对比分析
Comparatively Analysis of the Washing Methods for Transformer’s Condenser
 [PDF]

宋玉国,,
Smart Grid (SG) , 2012, DOI: 10.12677/SG.2012.23011
Abstract: 由于变压器厂家在冷却器的冷却管设计和制造,只考虑了满足它的流量和散热,而较少考虑冷却器实际使用环境和现场维护量,冷却管排列过密,冷却器受环境污秽程度严重,导致冷却器维护工作量加大。本文针对冷却器冷却片缝隙狭小,现场带电水冲洗效果不很理想问题,提出分析比较检修人员在清扫工作中,应该选用带电水冲洗还是用空气清洗较好,以此来减少我们的工作量、提高工作效率和工作质量。
Since the manufacturer of transformer usually consider only flux and heat dissipation of the transformer’s condenser while it is designed and manufactured, the using environment of the transformer’ condenser and field main- tenance is ignored and the cooling tube is closely spaced. Thus lead to some pollution problem by the environment and the maintenance cost is increased. This article comparatively analysis two kinds of washing methods. The result shows that using air washing has better effect than charged water washing. With that we can reduce washing workload, im- prove work efficiency and the quality.
氮化铝纳米线的气–固法制备及光学性能
静雅,吕惠民,
硅酸盐学报 , 2011,
Abstract: 以三氯化铝和叠氮化钠为原料,用复分解反应制备单晶氮化铝(AlN)纳米线。样品呈灰白色粉末,反应温度为650℃,反应时间为3h,并对该样品进行X射线衍射、透射电镜和选区电子衍射测试分析。结果表明样品为六方相氮化铝且为表面光滑的长直形圆柱状,直径为50nm左右,长度均在10μm以上,晶格常数分别为a=0.268nm、c=0.498nm。AlN样品性能的研究表明样品禁带宽度约为6.14eV,并对光致发光谱中各峰的形成原因进行分析。采用气–固生长机理和择优取向原理对单晶纳米线的生长进行解释。
中国客车产业升级的环境和趋势浅析
A Brief Analysis on the Environment and Trends of Bus Industry’s Upgrading in China
 [PDF]


Modern Management (MM) , 2015, DOI: 10.12677/MM.2015.52005
Abstract:
客车在客运交通中是基础式的存在。在国家汽车产业大规模增长和私家车大潮下,客车产业在汽车领域的“羹”越分越少。但客车行业发展的背景环境中,来自其他交通手段的外部环境给予客车行业的竞争是良性互补和促进式的,基于客车的客运业市场没有被过于压制。相比竞争,市场环境给客车行业的机遇更多。在当今市场需求和技术背景下,客车行业要升级,就要在技术上提升其原有的“车性”,在乘用上强化其“客性”,同时增加客车的智能化和商业服务附加值,争取通过新能源实现更经济更环保的交通。
Bus is a basic road traffic tool. These years, in China, the large-scale growth of automobile industry especially the increase of private cars brings nothing profit to bus companies but makes pressure instead. But rationally, competitors from other fields in the market also provide complementary furtherance to the bus industry, and the market share of buses is not being over-suppressed by them. Compared with the competitions, the marketing environment gives more opportunities to the bus industry. So, to accommodate the market demands, bus industry needs to self-upgrade. That means that bus must be turned to be a high additional value product which is more technical for driving, more commercial for various uses, more intelligent to drivers and passengers and more friendly to the nature. And, industry enterprises should try to use the new energy to realize a high cost performance and reliable new traffic base on bus.
先进高强钢DP1000地板中央通道的成形回弹及补偿研究
李贵,,陈志平,龙小裕,杨朋,梁中凯
- , 2018, DOI: 10.11951/j.issn.1005-0299.20170221
Abstract: 高强度钢板因具有较高的强度而易产生严重的回弹缺陷, 已成为其应用的最主要瓶颈.为此, 本文以某车型地板中央通道零件为载体, 针对其几何型面复杂、材料变形程度大的特点, 研究先进高强度钢板DP1000的冲压成形回弹及补偿特性.通过对该零件的冲压成形工艺方案进行优化设计和全工序回弹数值模拟, 并结合零件的几何特征和变形模式, 对各成形工序的回弹进行精确预测.基于预测结果对模具型面采用折入处理的方式进行全工序几何补偿, 实现回弹补偿的自工序完结.最后以补偿后的型面进行冲压实验, 并对零件的型面尺寸进行检测分析.结果表明, 全工序回弹数值模拟和型面几何补偿是解决复杂零件多工序冲压成形回弹问题的最有效方法.通过两次回弹补偿后, 该零件的回弹得到完全控制, 尺寸精度达到要求且成形质量良好.
Because of higher strength, the high strength steel is prone to cause serious springback defects, which has become one of the most important bottlenecks on its application.Therefore, the forming and springback of the floor panel tunnel of advanced high strength steel DP1000 is researched based on the characteristics of complex geometrical surface and large deformation.Through the optimization design of stamping process and numerical simulation of springback in the whole process and by combining with the geometric features and deformation modes the springback of each process is accurately predicted.Based on the prediction results, the geometric compensation of the whole process is achieved by the way of smooth break angle in the die surface, which realized the self closing of springback compensation in each process.Finally, the stamping experiment is carried out with the compensated dieface and the dimension of the stamping part is detected and analyzed.The results show that the springback numerical simulation of whole process and geometric compensation are the most effective methods to solve springback problems of multi-forming process of complex parts.After two springback compensations, the springback has been effectively controlled.The dimension precision meets the requirement and the forming quality is good.
残余压应力场中疲劳短裂纹扩展模型及实验
振旗,徐可为,胡奈
金属学报 , 1994,
Abstract: 结合实验讨论了残余应力对裂纹扩展作用的模型及其存在的问题.指出用公式ΔK_(eff)=(K_(max)+λK_r)-K_(op)可较准确地计算出残余压应力场中裂纹的扩展速率.残余压应力既使裂纹闭合力提高,又使最大应力强度因子降低,两者均使裂纹扩展驱动力ΔK_(eff)减少,因而降低了裂纹的扩展速率.
高氯酸-氢溴酸体系硒伏安法的研究
夏玉宇,张完白,,武卫
环境化学 , 2015,
Abstract: 本文采用卧滴汞电极-线性电位扫描极谱,研究了高氯酸-氢溴酸体系硒伏安法的各种条件及其机理,认为硒以SeBr62-阴离子形式吸附富集于正电荷的汞电极上,阴极溶出产生二个吸附峰蜂1SeBr62-+Hg+4e→HgSe+6Br-峰2HgSe+2H++2e→Hg+H2Se
肠易激综合征患者外周血雌激素孕激素及睾酮激素含量分析
,吴保平,
南方医科大学学报 , 2006,
Abstract: 目的检测肠易激综合征(irritablebowelsyndrome,ibs)患者外周血中性激素水平,探讨ibs发病与外周血性激素的关系。方法对符合罗马ⅱ标准的48例ibs患者及30例健康对照者的外周血中雌激素、孕激素和睾酮激素的水平用放射免疫r计数器测定,并用自动软件分析。结果对于男性ibs患者,其外周血中睾酮激素含量低于健康对照组(p<0.05),而雌激素、孕激素含量与健康对照组差异无显著性(p>0.05)。对于女性ibs患者,其外周血中雌激素含量低于健康对照组(p<0.05),而孕激素、睾酮激素含量与健康对照组差异无显著性(p>0.05)。结论男性ibs患者外周血中睾酮激素含量下降,女性ibs患者外周血中雌激素含量下降,提示ibs患者的发病可能与体内性激素水平紊乱有关。更多还原
一种软件体系结构设计决策的建模工具
,晓峰,孙艳春,黄罡?
计算机科学 , 2009,
Abstract: 体系结构设计在整个软件生命周期中起到关键作用,而设计知识的蒸发会导致系统演化花费代价高、涉众之间交流出现障碍、体系结构制品的复用受到限制等问题,为此需要在软件体系结构层次对设计决策进行显式化的建模。基于一种以决策为中心的体系结构设计方法,实现了一个软件体系结构设计决策的建模工具。该工具帮助架构师对体系结构设计中的问题、方案、决策、理由等核心概念进行建模,完成从需求到体系结构的设计过程,并实现了自动化的候选体系结构方案的合成和部分设计理由的捕捉。该工具还提供了体系结构设计模型与设计决策之间的相互追踪性,以及
精氨酸-甘氨酸-天冬氨酸-丝氨酸序列在生物活性玻璃对人牙髓细胞生物作用中的影响
Influence of the Arg-Gly-Asp-Ser sequence on the biological effects of bioactive glass on human dental pulp cells

刘意,,彩云,董艳梅
- , 2017, DOI: 10.3969/j.issn.1671-167X.2017.02.025
Abstract: 目的:生物活性玻璃(bioactive glass, BG)对人牙髓细胞(human dental pulp cells, hDPCs)的增殖及矿化有积极的作用,本研究目的是研究精氨酸-甘氨酸天门冬氨酸-丝氨酸序列(Arg-Gly-Asp-Ser,RGDS)在BG对hDPCs的黏附、增殖及矿化作用中的影响。方法:用含不同质量浓度RGDS(12.5 mg/L、25.0 mg/L、50.0 mg/L、100.0 mg/L、200.0 mg/L)的BG浸提液培养hDPCs,对照组为不含RGDS的BG浸提液。采用细胞活性噻唑蓝(MTT)比色法于接种后4 h检测细胞黏附数量,于第1、3、5、7、9天测定细胞增殖,第14、28天对细胞进行茜素红染色检测矿化活性。结果:BG浸提液加RGDS组与单纯BG浸提液组相比,hDPCs黏附数目降低,呈RGDS浓度依赖性;BG浸提液加RGDS组的增殖活性早期低于单纯BG浸提液组,但后期两组之间差异无统计学意义;BG浸提液能够促进hDPCs的矿化,加入RGDS组的矿化活性与单纯BG浸提液组差异无统计学意义。结论:游离态RGDS不影响BG对hDPCs的增殖和矿化促进作用,但会与hDPCs结合进而影响hDPCs向培养皿底的黏附。
Objective:Positive effects of bioactive glass (BG) on proliferation, mineralization, and differentiation of human dental pulp cells (hDPCs) was already verified in various former studies. The Arg-Gly-Asp-Ser sequence (RGDS) was confirmed of affecting cell adhesion. Before further investigation, the objective of this study is to investigate whether RGDS can affect the effects of BG on the adhesion, proliferation and mineralization of hDPCs. Methods: hDPCs were harvested from third molars of 18-25-year-old individuals after informed consent. Enzyme digestion technique was used. The 4th to 6th ge-neration of hDPCs were used for all experiments.The cells of the experimental groups were cultured in Dulbecco minimum essential medium (DMEM) containing ionic dissolution products of BG and RGDS of seve-ral concentrations (12.5 mg/L, 25.0 mg/L, 50.0 mg/L, 100.0 mg/L, 200.0 mg/L). DMEM containing ionic dissolution products of BG without RGDS was used for cell culture as control group. Cell adhesion was tested 4 h after cell seeding by MTT assay. Cell proliferation was examined at 1, 3, 5, 7, and 9 d after cell seeding by MTT assay. Cell mineralization was investigated on days 14 and 28 by alizarin red staining. After being stained and dried, mineralized nodules were dissolved by cetylpyridinium chloride (CPC) for semi-quantitative test. Results were statistically analyzed by one way ANOVA, SPSS (version 19.0) and P<0.05 was considered to be significant. Results: Cell adhesion in BG group showed no difference from that in DMEM group. Compared with BG group, hDPCs in BG+RGDS groups suggested weaker cell adhesion.When the concentration of RGDS increased, the adhered cell number decreased. hDPCs cultured with BG and RGDS showed lower proliferation activity in the early stage, while no significant difference was observed after 3 d. BG group promoted the mineralization of hDPCs compared with positive control group, negative control group and RGDS group. No significant difference was observed between BG+RGDS group and BG group or
基于ZigBee的环境检测的物联网的设计与研究
Design and Research of Internet of Things in Environmental Monitoring Based on ZigBee
 [PDF]

王挥,
Hans Journal of Wireless Communications (HJWC) , 2013, DOI: 10.12677/HJWC.2013.35018
Abstract: 随着社会的发展,人们对生活质量关注度越来越高,特别是对环境的关注。针对环境监测问题,结合ZigBee术,本文进行了基于ZigBee的环境监测的物联网的设计与研究。文章从技术研究与实际应用的角度出发,在深入分析了Z-Stack协议的基础上,详细阐述了基于TI公司提供的CC2530的开发平台应用层的设计与实现,并给出了一个基于ZigBee环境监测的实现方案,整套方案实现了使用传感器进行数据采集,节点传输,数据处理,以及智能终端查看的功能。本文设计的环境监测系统具有低复杂度、低功耗、易于部署等特点,对基于ZigBee的环境监测的普及具有一定的应用价值。
 With the development of society, people pay more attention to the quality of lives, especially the environmental conditions. The ZigBee-based Internet of Things in environmental monitoring is designed and discussed in this paper. From the perspectives of technical research and practical application, the paper elaborates the design and realization of the application layer on the TI’s CC2530 by exploring Z-Stack protocol. Furthermore, this paper describes the solution for environmental monitoring based on ZigBee, which implements a variety of functions including data collec- tion, data transmission, data processing, intelligent terminal view. The designed system has the following features: low complexity, low power consumption and ease of deployment which have some application values in prevalence of ZigBee-based environmental monitoring.
Page 1 /20497
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.