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1.
INTRODUCTION Polytetrafluoroethylene (PTFE) is one of themost important high insulating organic polymerelectret material which have been applied in manyfields such as sensors, generators and motors,dose-meters, and air filters at high temperature,biofunctional materials etc., especially since theexcellent charge storage stability and highquasi-static and dynamic piezoelectric coefficientsin porous PTFE film are reported (Xia et al., 1999;Schw?diauer et al.… 相似文献
2.
陈清洲 《河北大学成人教育学院学报》2012,(4):28-33
成人高等教育收费问题是一项十分复杂的系统工程。现阶段,成人高等教育根据各省(区、市)收费制度改革的现状和自身教学管理的实际,分别实行学年制收费制度、学年学分制收费制度和弹性学分制收费制度等不同的收费标准。针对成人高等教育收费制度的不完善、收费标准的不合理、收费管理的不规范等问题,要通过成本补偿的多元化、收费标准的合理化和收费管理的规范化等措施,构建学习成果互认的成人高等教育收费制度,促进成人高等教育又好又快地发展。 相似文献
3.
沈夏霞 《金华职业技术学院学报》2013,13(2):11-14
随着高职教育的发展,高职院校收费管理中的一些问题和矛盾日趋尖锐化,亟需加以解决。高职院校收费管理存在着院校内部各部门缺乏沟通,学生信息变更不及时、不完整,收费管理系统不完善,收费相关岗位设置不合理,业务流程设计不合理,内部控制与外部监督的力度不够,收费方式滞后,收费软件单一,收费管理方式落后等问题。必须加强院校各部门的沟通,做好学生信息管理,合理设置收费相关岗位,业务流程设计合理化,内部控制和外部监督双管齐下,采用先进的电子网络技术,实现网络化收费等,以促进高职院校教育事业健康、快速发展。 相似文献
4.
Low-Temperature Plasma Induced Grafting of 2-Methacryloyloxyethyl Phosphorylcholine onto Poly（tetrafluoroethylene） Films 总被引：1，自引：0，他引：1
Modification of poly(tetrafluoroethylene) (PTFE) films with 2-methacryloyloxyethyl phosphorylcholine (MPC) was performed by
low-temperature plasma treatment and grafting polymerization. Surface properties of PTFE were characterized by attenuated
total reflectance Fourier transform infrared (ATR-FTIR) spectra, X-ray photoelectron spectroscopy (XPS), and static contact
angle. The results show that MPC has been grafted onto PTFE film surface successfully. Contact angle for the modified PTFE
films in the water decreased from 108° to 58.25°, while surface energy increased from 17.52 mN/m to 45.47 mN/m. The effects
of plasma treatment time, monomer concentration and grafting time on degree of grafting were determined. In the meanwhile,
blood compatibility of the PTFE films was studied by checking thrombogenic time of blood plasma. 相似文献
5.
1 Ｉｎｔｒｏｄｕｃｔｉｏｎ Ｏｗｉｎｇｔｏｉｔｓｈｉｇｈｈｙｄｒｏｇｅｎ ｓｔｏｒａｇｅａｂｉｌｉｔｙ ,ｌｏｗｃｏｓｔａｎｄａｂｏｕｎｄｉｎｎａｔｕｒａｌｒｅｓｏｕｒｃｅｓ ,Ｍｇ ｂａｓｅｄａｌｌｏｙｂｅ ｃｏｍｅｓａｃｏｍｐｅｔｉｔｉｖｅｈｙｄｒｏｇｅｎ ｓｔｏｒａｇｅｍｅｄｉｕｍｗｈｉｃｈｃａｎｂｅｕｓｅｄｉｎＮｉ ＭＨｂａｔｔｅｒｙａｎｄｆｕｅｌｃｅｌｌ.Ｔｈｅｅｌｅｃ ｔｒｏｃｈｅｍｉｃａｌｍｅｔｈｏｄｈａｓｂｅｅｎｕｓｅｄｉｎｔｈｅｓｔｕｄｙｏｆｈｙ ｄｒｏｇｅｎａｔｉｏｎ/ｄｅｈｙｄｒｏｇｅ… 相似文献
6.
周殿凤 《唐山师范学院学报》2013,(5):44-45
运用可编程逻辑器件CPLD设计了一款并网光伏发电控制器。该控制器由CPLD开发平台、温度传感器、接口电路组成,充电采用PWM方式控制。该控制器具有自动运行、双向切换的功能,可杜绝孤岛效应,并可对蓄电池的充放电进行保护。 相似文献
7.
Rechargeablealkalinenickelbatteries (e.g.,Ni/Cd ,Ni/Fe,Ni/Zn,Ni/H2 andNi/MH)areusuallypos itivelimited ,sothatthecapacityandcyclelifeofthecellsaredeterminedmainlybytheperformancesofnickelelectrodes.Withtheirhighenergydensityandlowcostrelativetothatofconventionalsinterednickelelectrodes,pastednickelelectrodeshavenowbeenwidelyusedincommerciallyavailableNi/MHbatteries[1 ,2 ] .Asthedis charged stateactivematerialofthepastednickelelec trodes,thepropertyofsphericalnickelhydroxideisthekeytodeter… 相似文献
8.
To fully take advantage of external charging conditions and reduce fuel consumption for extended-range electric vehicles, a charging management-based intelligent control strategy is proposed. The intelligent control strategy is applied to different driving patterns based on the various characteristics of urban roads. When the vehicle is driving on arterial roads, a constant power control strategy is applied. When the driver decides to go to a charging station, the extender-off time can be determined based on the current state of the vehicle and the distance to the charging station. When the vehicle is driving on an expressway, a power follower control strategy is applied. The range-extender engine is controlled to work over a wide variety of regions to obtain optimum fuel economy. The simulation results indicate that as the vehicle arrives at the charging station, the proposed charging management-based intelligent control strategy has made the state of charge reach the lowest permissible level after the driver made the decision to charge at the charging station. Therefore, the driver can charge the vehicle with as much clean electric energy as possible from the charging station. 相似文献
9.
张正义 《山西财经大学学报(高等教育版)》2004,7(3):55-59
山西普通高校现行的学费收费标准是2000年制定的。目前，山西高等教育系统内部呼吁，要适当提高学费收费标准。学费收费标准问题既是一个经济问题，又是一个政治问题。山西普通高校同学科、同专业现行学费收费标准与其他省份比确实存在收费低的问题，可研究解决。但从长远看，解决高校经费不足，最终还要靠拓宽经费来源渠道来解决。 相似文献
10.
LIU Zuohu LIU Renlong DU Jun TAO Changyuan LI Xiaohong College of Chemistry & Chemical Engineering Chongqing University Chongqing P. R. China College of Resources & Environmental Science Chongqing University Chongqing P. R. Chin 《重庆大学学报(英文版)》2004,3(1):61-64
1.IntroductionPhenolisanimportantchemicalindustrymaterial,butitalsoaboundswithserioushazardtoenvironmentandthreatstohumanhealth.Rigidruleshavebeenmadeoutonthephenoldischargeconcentration.Researchesonthetreatmentofphenolwastewaterwerecarriedoutinvariouscountries[1-5].Membraneseparationmethodsincludingreverseosmosis,ultrafiltrationandpervaporationhaveattractedmuchattentionforphenolwastewatertreatment,withcelluloseacetate(CA)membraneemployedmostly[6].Membranedistillationisanewmembraneseparation… 相似文献
11.
李强 《商丘职业技术学院学报》2013,12(3):97-98,101
高校收费管理工作是高校财务管理的重要组成部分,收费资金在高校各项建设中发挥着举足轻重的作用。受计划经济思维模式等多种因素的影响,高校领导普遍对高校收费工作缺乏足够的重视,导致管理混乱、内控缺失,给学校造成巨大损失。由于收费工作是一项系统工作,需要各职能部门的密切配合。收费工作能否顺利开展,直接关系到学院的稳定与发展。本文阐述了当前高职院校收费管理工作的现状及存在的问题,提出了一些对策、建议,对收费管理工作的未来发展方向提出了展望。 相似文献
12.
浅谈中国大学教育收费 总被引：2，自引：0，他引：2
当前我国大学教育已经进入收费教育阶段。本文将当前中国大学教育的收费状况、收费标准计算和收费依据与国外大学教育收费的情况作了简要的比较,并分析了产生高学费的主要原因,提出了政府要从切实增加教育经费的支出力度等6个方面来解决中国大学教育高收费和高收费中贫困生的教育费用负担问题。 相似文献
13.
将碳酸钙颗粒分散于聚苯乙烯溶液中,并在石英晶体微天平（QCM）表面成膜,以稀盐酸将膜中的碳酸钙颗粒溶解,获得多孔的聚苯乙烯薄膜,以QCM动态传感监测表面活性剂在多孔膜上的吸附过程．结果表明,十二烷基苯磺酸钠、氯代十六烷基吡啶、TX-114均在聚苯乙烯薄膜上吸附,三种表面活性剂在多孔膜上的吸附动力学和等温线可以分别用Langmuir动力学和等温线模型回归分析,得到了有关吸附动力学参数和吸附等温线参数． 相似文献
14.
弹性金属氟塑料径向滑动轴承润滑特性的实验研究及建模仿真 总被引：1，自引：0，他引：1
In recent years, much attention has been devoted to the design and operation of bearings made of elastic metal plastic (EMP).The surface of the bearing bush is covered by a layer of polymer PTFE(polytetrafluoroethylene).The physical performances of the polymer are quite different from that of metal.It can reduce friction because of its lower surface energy, and it is more difficult for the fluid to be adhered.Consequently, the slip will exist at the oil-bush interface.The journal bearings made of this material are researched in this article.Through test, the existence of slip is proven and the equation of the slip velocity for the EMP journal bearing is established when shear stress up to a certain value.Thus, the classical Reynolds equation is modified.The lubrication mechanism is analyzed by some simulation results. 相似文献
15.
李敏 《黄冈职业技术学院学报》2009,11(2):44-45
本设计利用电磁感应原理实现电能的无线传递,采用TI公司的MSP430F2274超低功耗单片机作为无线传能充电器的监测控制核心。通过开关还可以选择充电的速度,实现快速充电和常态充电功能,电能充满后给出充满提示且自动停止充电。 相似文献
16.
In recent years, much attention has been devoted to the design and operation of bearings made of elastic metal plastic (EMP). The surface of the bearing bush is covered by a layer of polymer PTFE(polytetrafluoroethylene). The physical performances of the polymer are quite different from that of metal. It can reduce friction because of its lower surface energy, and it is more difficult for the fluid to be adhered. Consequently, the slip will exist at the oil-bush interface. The journal bearings made of this material are researched in this article. Through test, the existence of slip is proven and the equation of the slip velocity for the EMP journal bearing is established when shear stress up to a certain value. Thus, the classical Reynolds equation is modified. The lubrication mechanism is analyzed by some simulation results. 相似文献
17.
封红梅 《河北广播电视大学学报》2012,17(2):66-67
随着我国高等教育事业发展壮大,高校收费工作的重要性日益凸显。银行代理收费系统是近年来高等学校收费工作采用的一种新型方式,与传统收费方式相比,可以极大地减轻现场收缴现金的安全风险,不仅使学生享受便捷安全的服务,也提高了财务工作效率。在使用银行代理收费系统收费实务中,需要将各个操作环节流程化,并对缴费代码、代理收费额度、反馈信息等工作要点作好安排。 相似文献
18.
我国从1989年开始实施高等学校收费制度,自1999年实行全面并轨制后,高校收费呈现出的上升态势并没有降低老百姓对高等教育的需求,教育需求增加的同时也给高等教育市场带来了一些问题。文章试图从教育需求的角度,分析高校收费制度下高等教育需求增加的原因,并提出了坚持用科学的发展观指导高等教育的发展。 相似文献
19.
ＩＮＴＲＯＤＵＣＴＩＯＮＳｅｒｉｅｓｂａｔｔｅｒｙｓｔｒｉｎｇｓａｒｅｗｉｄｅｌｙｕｔｉｌｉｚｅｄｉｎｍａｎｙａｐｐｌｉｃａｔｉｏｎｓｓｕｃｈａｓｔｅｌｅｃｏｍｍｕｎｉｃａｔｉｏｎｐｏｗｅｒｓｕｐｐｌｉｅｓ,ｅｌｅｃｔｒｉｃｖｅｈｉｃｌｅｓ,ｕｎｉｎｔｅｒｒｕｐｔｅｄｐｏｗｅｒｓｕｐｐｌｉｅｓａｎｄｐｈｏｔｏｖｏｌｔａｉｃｓｙｓｔｅｍｓ,ｅｔｃ .Ｔｈｅｌｉｆｅｔｉｍｅｏｆａｂａｔｔｅｒｙｉｓｏｎｅｏｆｔｈｅｍａｊｏｒｆａｃ ｔｏｒｓｔｈａｔｌｉｍｉｔｔｈｅｒｅａｌｉｚａｔｉｏｎｏｆａｎｅｃｏｎｏｍｉ… 相似文献
20.
给出球状液滴表面张力和等摩尔面和张力面的计算公式,用分子动力学模拟了温度T*=0.65不同粒子数的球状液滴,计算了Tolman长度δ;计算同一温度下平液面的表面张力,利用Tolman方程计算δ。结果都显示δ取正值,随液滴半径增加而减小。 相似文献