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1.
建立中国顾客满意指数若干问题的研究   总被引:8,自引:1,他引:7  
介绍了顾客满意指数(Customer Satisfaction Index,CSI)测评的发展历程,并研究了具有代表性的美国顾客满意指数(American Customer Satisfaction Index,ACSI);然后,对建立中国顾客满意指数(Chinese Customer Satisfaction Index,CCSI)中的若干问题进行了研究,研究指出,CCSI在建立过程中,应该遵循以下4个原则;(1)测评对象具有统一性;(2)测评结果具有可比性;(3)测评结果具有有用性;(4)考虑中国市场中的实际情况。  相似文献   

2.
腐蚀科学与防护技术值得注意的发展动向   总被引:6,自引:0,他引:6  
杜元龙  柯克 《材料保护》2000,33(1):16-19
论述了腐蚀科学与防护技术几个值得注意的发展动向,它们包括:(1)金属/腐蚀介质界面反应及其快速步骤的原位研究;(2)在腐蚀环境中结构的可靠性;(3)腐蚀的在线无损检测/评价和设备的维修保养;(4)材料优选的新方法-LCC;(5)防护系统工程学;(6)腐蚀防护与环境保护;(7)微生物蚀(MIC);(8)腐蚀防护的计算机辅助设计;(9)钢筋混凝土结构的腐蚀防护;(10)海洋工程结构的腐蚀防护;(11)  相似文献   

3.
驾驶风格指驾驶员在日常生活中习惯性的驾驶方式.本文对这一领域的研究进行了回顾和归纳,指出了驾驶风格的概念、影响因素及主要测量方法(多维度驾驶风格量表和驾驶风格问卷);并针对当前研究的不足,提出了未来研究的3个方向:(1)拓展驾驶风格研究的广度和深度;(2)重视驾驶风格测量的应用;(3)加快驾驶风格的本土化研究.  相似文献   

4.
聚合物/炭黑复合材料PTC特性的理论研究进展   总被引:18,自引:0,他引:18  
关于聚合物/炭黑复合物材料PTC特性的机理研究,提出了许多理论模型,文中几个具有代表性的模型,即(1)导电链与热膨胀模型;(2)隧道导电模型;(3)炭粒聚集态结构变化及迁移模型;(4)欧姆导电机理及相变模型等进行分析和讨论,指出了各种模型的特点与缺陷,认为进一步研究了PTC现象的机理,完善相应的理论模型,是该领域中一项长期的工作。  相似文献   

5.
杜平  赵安中 《功能材料》1999,30(6):617-619
铠装热电偶在高温使用时,常出现电分流而影响测量精度,本工作进行了以下研究:(1)热电偶分流模拟实验;(2)分流误差数学模型及计算公式;(3)影响分流误差因素分析。  相似文献   

6.
《现代材料动态》2009,(3):23-23
大阪大学研究生院工学研究系桑烟进教授、名古屋大学研究生院工学研究系鸟本司教授及日本爱德克(IDEC)的联合研究小组,通过采用光蚀刻方法控制(AgIn)xZn(1-2x)S(银&;#183;铟&;#183;锌&;#183;硫)这种新组成的半导体纳米粒子直径,令其成功地发出多种颜色的荧光。  相似文献   

7.
以Pb(NO3)2、ZrOCl2·8H2O和TiCl3为原料,采用电化学还原的方法,制备出了氧化铅纳米棒。用扫描电镜(SEM)、透射电镜(TEM)、X射线能量分散谱(EDS)和x射线衍射仪(XRD)研究产物的微观形貌和晶体结构。研究结果表明:用电化学还原法制备的氧化铅纳米棒是单晶的结构,氯离子的存在对产物有很大的影响。  相似文献   

8.
采用激光化学气相沉积(LCVD)技术在氧化铝衬底上制备了高取向的TiNx薄膜,重点研究了激光功率(PL)、衬底预热温度(Tpre)和沉积总压力(Ptot)对薄膜取向和沉积速率的影响,采用X射线衍射(XRD)、俄歇能谱(AES)和场发射扫描电镜(FESEM)对薄膜组成和结构进行了表征.结果表明:所得到的TiNx薄膜成分均匀,其取向与衬底预热温度有关,随着预热温度的升高,TiNx薄膜的取向由(111)变为(200),薄膜的取向与其微观结构一致.TiNx薄膜的沉积速率随着激光功率升高而增大,在PL=100W时,达到最大值90μm/h(沉积面积为300mm2),显著高于采用其它方法制备的TiNx薄膜.  相似文献   

9.
本文介绍了碱骨料反应的定义以及碱骨料反应发生的条件、对比了国内外抑制碱骨料反应的主要措施以及用于高性能混凝土中的抑制措施研究状况,通过比较可以得出抑制碱骨料反应的主要措施为:(1)使用非活性集料;(2)控制水泥和混凝土碱含量(Na2O,Na2O+0.658K2O);(3)控制湿度;(4)使用混合材或化学外加剂。  相似文献   

10.
冷轧态SiCp/LY12复合材料超塑性及变形机制   总被引:2,自引:0,他引:2  
研究了冷轧态SiC颗粒(dp=10μm)增强LY12复合材料(SiCp/LY12)的超塑性,着重探讨了变形机制。研究表明:(1)在温度T=803K(比熔点高26K),初始应变速度ε0=4.8×10^-4s^-1时,应变速度敏感系数m值为0.49,延伸率达240%;(2)超塑性变形后的晶粒尺寸约为10μm;(3)该事材料超塑性变形的主要机制是晶界液相和基体中动态回复调节的但却受界面液相和界面扩散流释  相似文献   

11.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

12.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

13.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

14.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

15.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

16.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

17.
As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.  相似文献   

18.
Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.  相似文献   

19.
TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.  相似文献   

20.
The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.  相似文献   

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