后续的KOH腐蚀对ZnO纳米棒阵列及性能的影响

采用化学沉积和KOH腐蚀结合的方法,在FTO导电玻璃上制备了ZnO纳米棒阵列。用XRD、SEM、I-V曲线对ZnO纳米棒阵列的结构和性能进行了表征。结果表明:ZnO纳米棒为单晶,属于六方纤锌矿结构。后续的KOH腐蚀有利于ZnO纳米阵列形貌的改变及光电性能的提高,将ZnO纳米棒阵列作为光阳极制备染料敏化太阳能电池,被KOH腐蚀后的ZnO纳米棒阵列的光电转换效率(η)、短路电流(Jsc)、开路电压(Voc)分别达到1.2%、0.006A/cm2、0.557V,与未被KOH腐蚀的ZnO纳米棒相比,光电转换效率提高了1.05%。     

ZnO纳米四脚状阵列电极染料敏化太阳能电池

采用化学气相沉积(CVD)法制备了不同尺寸的四脚状纳米ZnO和ZnO纳米棒。采用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)对纳米ZnO的晶型结构和形貌进行表征,研究结果表明CVD法制备的四脚状纳米ZnO具有三维空间结构,其最小平均臂宽约为70nm,臂长约300nm,制备的纳米棒直径约为84nm,长约2μm,且都为六方纤锌矿晶型结构。将ZnO纳米四脚状及纳米棒利用滚涂法在FTO导电玻璃上形成ZnO光阳极,经N719染料敏化后组装成染料敏化太阳能电池,光电性能结果表明,染料敏化小尺寸的四脚状纳米ZnO太阳能电池光电转换效率(η=1.88%)高于染料敏化大尺寸的四脚状纳米ZnO太阳能电池光电转换效率(η=1.18%),远高于染料敏化ZnO纳米棒太阳能电池的光电转换效率(η=0.7%)。     

ZnO/TiO2纳米管晶膜电极的制备及光电性能

采用水热法制备了ZnO纳米棒,以ZnO纳米棒为原料制备出ZnO/TiO2纳米管晶膜电极并应用于染料敏化太阳能电池.用扫描电镜(SEM)、X射线衍射仪(XRD)、X射线能谱仪(EDX)和N2吸脱附分析等研究了样品的结构、表面形貌和化学组成,并通过紫外可见光度计和电化学工作站探讨了煅烧温度在80~600℃范围内ZnO/TiO2纳米管电极的光电化学性能.此外,研究经TiCl4化学处理的ZnO/TiO2纳米管电极光电性能的改善情况.结果表明,600℃煅烧的ZnO/TiO2纳米管电极制备的染料敏化太阳能电池表现出较优的光电性能,其短路电流密度(Jsc)为2.28 mA/cm2,开路电压(Voc)为0.631 V,光电转换效率η为0.66%.600℃煅烧的ZnO/TiO2纳米管经TiCl4处理后的染料敏化太阳能电池的光电性能得到显著改善,其光电转换效率η提高到1.06%.     

Cu_2O敏化ZnO纳米棒的制备及其对光电性质的影响

以透明导电玻璃(FTO)为基底,采用电化学沉积法制备了Cu_2O敏化的ZnO纳米棒阵列复合薄膜。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电镜(TEM)、高分辨电镜(HRTEM)、电化学工作站研究了不同Cu_2O沉积时间对复合薄膜的晶体结构、形貌、光电性质的影响。结果表明,电化学沉积的Cu_2O纳米晶可以与ZnO纳米棒形成异质结,提高ZnO纳米薄膜的光电转换效率,当Cu_2O的沉积时间为5min时,Cu_2O敏化ZnO纳米棒薄膜的光电转换效率最高。     

ZnO纳米团簇与CdSe纳米棒复合膜的光电化学性能研究

用水热法合成了粒径均匀、分散良好的花状ZnO纳米团簇和CdSe纳米棒.讨论了ITO/ZnO/CdSe复合膜电极光电性能的影响因素,对比研究了ITO/ZnO纳米团簇及ITO/CdSe纳米棒膜电极的光电化学性能,实验表明:复合膜电极拓展了在长波方向的光吸收,提高了光电转换效率;当ZnO与CdSe复合摩尔比为1∶3时,ITO/ZnO/CdSe纳米复合膜电极在本实验中得到最高光电转换效率(IPCE)25.27%,远远高于单一ITO/ZnO花状纳米团簇膜电极和ITO/CdSe纳米棒膜电极.     

Zn/纳米棒阵列ZnO/聚噻吩复合电极的制备及光电化学性质

使用简单的水热法在锌片上生长ZnO纳米棒阵列,并用电化学共聚制备了ZnO纳米棒阵列与聚噻吩(Zn/ZnO/PTH)复合膜。通过X射线衍射(XRD)、扫描电子显微镜(SEM)等手段对ZnO的结构和形貌进行表征,XRD结果表明产物为六方纤锌矿型ZnO。SEM结果表明,在垂直锌片方向生长了包括纳米棒、纳米片、纳米线的表面光滑的ZnO纳米阵列,其中以纳米棒为主,其直径为30～100nm,长度1μm。用光电流作用谱、光电流-电势图研究了Zn/ZnO/PTH电极的光电转换性质。结果表明,PTH修饰ZnO/Zn电极可使光电流产生波长发生明显红移,使其光电转换效率提高了4倍,填充因子FF=33%,光电转换效率η=1.25%。     

CdSZnO核壳纳米棒阵列结构的制备及在太阳能电池中的应用

采用水热法制备垂直于FTO导电玻璃基底的ZnO纳米棒阵列,然后通过电化学沉积法在ZnO纳米棒阵列上沉积CdS纳米晶,形成CdS/ZnO核壳纳米棒阵列结构。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线能谱仪(EDS)和紫外-可见分光光度计(UV-Vis)等对所得样品的形貌、结构组成进行分析表征;并以其为光电极组装太阳能电池,研究CdS纳米晶厚度对该电池光电性能的影响。结果表明,所得样品不仅拓宽和加强电池的光吸收能力,也有效调控光生载流子的传输。当CdS纳米晶沉积时间为60s时,电池的光电转换效率最高可达1.10%。     

染料敏化太阳电池石墨/聚苯胺复合对电极的低温制备和性能

通过低温制备(120℃)构建出不同比例石墨/聚苯胺复合对电极,分析了复合对电极组装的染料敏化太阳电池(DSCs)的光电性能,并通过X射线衍射仪、傅里叶红外光谱仪、电化学交流阻抗法和循环伏安法等表征方法探讨了光电性能变化的内在原因,同时探讨了复合对电极中引入镍纳米颗粒对DSCs光电性能的影响。结果表明:在对电极中,聚苯胺质量含量25%的复合对电极对I_3~-/I~-氧化还原反应具有更佳的催化活性,其DSCs短路电流密度、开路电压分别达到7.41mA·cm~(-2),和0.595V,其DSCs光电转换效率最大为2.193%,与纯石墨对电极和纯聚苯胺对电极时相比,光电转换效率分别提高了86.6%和45.3%。添加镍纳米颗粒后,导致复合对电极串联电阻的增加以及催化活性的弱化,最终促使相应器件的四个光电性能参数均有不同程度的下降。     

柔性SnO_2/ZnO复合光阳极的制备及其在染料敏化太阳能电池中的应用

通过简单易行的方法制备了SnO_2/ZnO复合纳米颗粒,利用XRD对SnO_2/ZnO结构进行表征。使用电泳技术制备无裂纹SnO_2/ZnO复合薄膜,考察了ZnCl2添加量对SnO_2/ZnO复合薄膜光阳极性能的影响,通过机械压膜方法对柔性导电衬底(ITO/PEN衬底)上的SnO_2/ZnO复合薄膜进行后处理,扫描电镜结果表明机械压膜处理使SnO_2/ZnO复合薄膜变得更加平滑,SnO_2/ZnO复合纳米颗粒之间的连接性能增强,光电测试结果表明机械压膜处理可以显著提高SnO_2/ZnO复合光阳极的光电性能,电池的开路光电压和短路光电流均得到明显提高,优化后柔性SnO_2/ZnO复合光阳极组装的染料敏化太阳能电池的光电转换效率(η)达到了3.95%,短路光电流密度(JSC)、开路光电压(VOC)和填充因子(FF)分别为16.43mA/cm2、0.493V和0.49。     

ZnO/Pt光阳极的水热法一步合成及其光电化学性能

展示了一种非传统的水热方法,由金属薄膜与超纯水的一步水热法合成制备ZnO薄膜负载Pt纳米粒子的光阳极催化剂。通过改变初始金属薄膜的成分,可以调节光阳极中Pt纳米粒子的负载量,并通过对光电化学催化水分解效率的测量,系统探讨Pt负载量对光阳极催化剂光电化学性能的影响。由于该水热法所生成的光阳极催化剂具有独特微纳结构,因此该ZnO/Pt复合光阳极即使在催化剂质量为微克级时仍表现出高的催化活性,并且随着Pt纳米粒子负载量的增加,其水分解性能得到提高。当Pt纳米粒子的物质的量分数为5.6%时,ZnO/Pt复合光阳极光电流密度达到最大值,约为纯ZnO光阳极光电流密度的1.3倍。不仅制备出一种高催化活性的复合光电催化剂,而且为氧化物半导体贵金属复合催化剂的制备提供了一种简单、绿色的新方法。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

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.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

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.……     

Deposition and Coating Properties on CVD Tungsten

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.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

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.     

Low-Temperature Properties of Silver

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.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

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.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

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.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

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.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

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.     

Evaluation of fatigue life of steel using steel grain size

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.