Sb掺杂量对ATO纳米颗粒结构及激光吸收性能的影响(英文)

以SnCl4·5H2O和SbCl3为原料,采用共沉淀法制备不同Sb掺杂量的氧化锡锑(ATO)纳米粉末。分别采用XRD、FESEM、紫外可见分光光度计和激光器对晶体结构、形貌、激光反射率进行表征,研究Sb掺杂量对ATO纳米颗粒的结构、晶粒尺寸和激光反射性能的影响。结果表明:共沉淀法制备的ATO纳米颗粒为四方相金红石结构,粒径大小约为几十纳米;随着Sb掺杂量的增加,ATO的晶粒尺寸减小,晶胞体积则逐渐增大;与未掺杂的SnO2粉末相比,Sb掺杂后的ATO粉末在1.06μm激光波长处的反射率明显低于未掺杂的SnO2的反射率;随着Sb掺杂量的增加,反射率值呈先减小后增大的趋势,在Sb掺杂量为20%时,ATO粉末在1.06μm激光波长处的反射率低于0.02%,激光隐身性能最佳。     

A self-propagating high-temperature synthesis method for synthesis of zinc oxide powder

A self-propagating high-temperature synthesis (SHS) method has been developed for synthesis of ZnO powder. Powders of Zn and an appropriate amount of NH₄NO₃ were mixed and pressed into a compact place in a closed chamber with air atmosphere. The combustion reaction was ignited by heating the reactant compact directly using nichrome coil, and then as-synthesized products mainly composed of tetrapod whiskers could be obtained. Both the reaction phenomenon and the product yield were affected by the reactant composition and the stacking density, which might be explained by a proposed reaction mechanism.     

ATO纳米粉体的性能特点与制备研究现状

详细介绍了锑掺杂二氧化锡(ATO)纳米粉体良好的导电抗静电性能、浅色透明性、良好的耐候性和稳定性、纳米粒子特性、多功能性等性能特点,简述了ATO纳米粉体的应用领域;综述了目前制备ATO纳米粉体的固相法、水热法和化学共沉淀法等方法,对几类制备方法优缺点进行分析,进一步确定改进的化学共沉淀法和水热法制备ATO纳米粉体时的最佳实验条件.指出了目前ATO纳米粉体制备存在的几点问题,为进一步研究ATO纳米粉体的制备提供参考依据.     

单分散锑掺杂氧化锡(ATO)纳米材料的制备及其自组装(英文)

通过水热法制备了单分散的锑掺杂氧化锡(ATO)纳米材料,TEM表征显示所得的ATO纳米材料分散性好,粒径小,粒度分布窄。在使用特定表面活性剂的情况下,ATO纳米颗粒表现出一些自组装的行为,颗粒组装成规则的高分散纳米球体。     

表面修饰层厚度对Fe:ZnSe纳米晶光学性能的影响

利用硫代乙醇酸作为稳定剂在水相中合成了Fe:ZnSe/ZnS核/壳结构半导体纳米晶,研究了表面修饰层(壳层)厚度对产物光学性能的影响。XRD和UV-Vis吸收谱表明,合成的半导体纳米晶为核壳纳米晶,呈立方闪锌矿结构。TEM结果表明,产物分散性较好,尺寸均一,呈球形。PL结果表明,适当厚度的ZnS壳层能有效钝化Fe:ZnSe纳米晶表面的非辐射复合位点,当壳层过厚时,ZnS壳层产生的非辐射复合缺陷会导致PL强度下降。     

导静电涂料导静电性能与防腐蚀性能的关系

从添加型导静电涂料的导静电机理和钢铁的防腐蚀原理出发,讨论了导静电涂料导静电性能与防腐蚀性能的关系,认为具有良好导静电性能的涂料其防腐蚀性能必然较差的观点是值得商榷的.分析了市场上三类不同添加型导静电涂料的优缺点,提出了液体石油储罐内部的涂装防护措施,对于储罐内使用的导静电涂料,建议适当提高其耐盐雾性能指标.     

Preparation of antimony-doped nanoparticles by hydrothermal method

Antimony-doped tin oxide (ATO) nanoparticles were prepared by the mild hydrothermal method at 200℃ using sodium stannate, antimony oxide, sodium hydroxide and sulfuric acid as the starting materials. The doped powders were examined by differential thermal analysis(DTA), X-ray diffractometry(XRD) and transmission electron microscopy(TEM). The doping levels of antimony were determined by volumetric method and iodimetry.The results show that antimony is incorporated into the crystal lattice of tin oxide and the doping levels of antimony in the resulting powders are 2.4%, 4.3%and 5.1%(molar fraction). The mean particle size of ATO nanoparticles is in the range of 25 - 30 nm. The effects of antimony doping level on the crystalline size and crystallinity were also discussed.     

一种环保水性抗静电防腐蚀涂料的性能研究

在水性环氧树脂及固化剂双组分体系中,采用浅色导电云母粉和钛白粉,优选环保型防锈颜料,运用扫描电镜、激光粒度分析仪、表面电阻率测试仪等分析手段研究了导电云母粉的粒径、用量、搅拌分散速度、钛白粉用量以及防沉剂的种类对涂层抗静电性的影响;研究了树脂/固化剂比例、体系颜料体积浓度及防锈颜料种类对涂层综合性能的影响;制备出了一种兼具良好抗静电性、优异防腐蚀性以及良好装饰性的环保水性抗静电防腐蚀涂料。     

Fireside corrosion in German fossil-fuel fired power plants. Appearence,mechanism and causes

Fireside corrosion in German fossil fuel-fired boilers is described out of the view of a laboratory engaged with failure analysis. With German boiler design and German fossil fuel ferritic steels can be used for the tubing in the evaporator and superheater section. Corrosion rates, which have to be expected normally are below 10 nm/h for evaporator tubes and below 25 nm/h for superheater tubes. The appearance of corroded tubes is described and discussed in respect of the corrosion mechanism. In the evaporator section enhanced corrosion risk is mainly due to an increased chemical load, namely reducing conditions or chlorine compounds in the combustion products. In the superheater section higher than normal metal temperatures and stresses, by which the integrity of the oxide layer is destroyed, are the most important factors for increased corrosion rates.     

SnAgCuCe/Er无铅钎料表面锡晶须的形态及特性

在Sn-3.8Ag-0.7Cu无铅钎料中添加1%(质量分数)的稀土铈或铒会在其内部形成尺寸较大的稀土相CeSn3和ErSn3.暴露于空气中的CeSn<,3和ErSn3将发生氧化,同时在其表面会出现锡晶须的快速生长现象.文中研究了稀土相CeSn3与ErSn3表面锡晶须的生长行为.结果表明,在CeSn3与ErSn3表面形成了大量的传统圆柱状锡晶须,同时,在其表面还出现了一些特殊形态的锡晶须,如带纹状的锡晶须、扭曲状的锡晶须、变截面的锡晶须、锡晶须的分枝、合并及搭接现象等.     

High temperature corrosion in gases with low oxygen partial pressure

The technological importance of the high temperature corrosion behaviour of metals in gases with a low oxygen potential and containing other oxidants is outlined. This indicates the wide interest in the role of sulphur and also chlorine compounds, their aggressiveness being such in low oxygen potentials that serious corrosion rates can occur even below 400°C. The scientific basis of our understanding of corrosion in such atmospheres is discussed, and applied to the case of corrosion in sub-stoichiometric combustion products in pulverized coal boilers.     

基于BP神经网络的聚酯玻璃钢加速老化寿命预测

采用BP神经网络对聚酯玻璃钢氙弧灯加速老化的弯曲寿命进行了预测.通过对聚酯及其玻璃钢的人工氙弧灯加速老化,测试其不同老化时间的弯曲强度,对弯曲强度与老化时间进行BP神经网络的建模分析,借助MATLAB软件对壤酯玻璃钢的使用寿命分别进行分析与预测,并采用最小二乘法对所预测的结果进行了对比.结果表明:在以弯曲强度达到初始强...     

Effect of antimony doped tin oxide on behaviors of waterborne polyurethane acrylate nanocomposite coatings

A multi-functional waterborne polyurethane acrylate (WPUA) nanocomposite coating was prepared through introducing the acrylate groups into the end of the polyurethane main chains and then modified by antimony doped tin oxide (ATO) nanoparticles by ultrasonic dispersion. Structural and morphological features of coatings were assessed using Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and a 3D measuring laser microscope. Performance of the coatings was evaluated using water resistance studies, thermogravimetric analysis (TGA), dynamic mechanical thermal analysis (DMTA) and mechanical tests such as tensile strength, elongation at break. The data showed that the WPUA/ATO coatings possessed good mechanical properties and thermal stability. The UV-visible-near infrared (UV-VIS-NIR) spectra results suggested that the WPUA/ATO coatings could absorb near infrared radiation so that it would prevent heat transmission and heat diffusion effectively.     

过氧化甲乙酮安全使用

过氧化甲乙酮属强氧化剂,常应用于玻璃钢制品生产和工业防腐施工中做为不饱和聚酯树脂固化剂的有机强氧化剂。它对呼吸道有刺激作用,会灼伤皮肤和眼睛;对热敏感,可燃且助燃,遇火源、火花(电火花)、静电或接触还原剂会引起剧烈反应,产生燃烧或爆炸。为此必须对其进行正确使用和管理,做到安全使用。     

高压富氧下几种高温合金的燃烧特征和性能研究

利用高压富氧点燃设备,在氧气压力为2.0MPa、氧气浓度为99%的条件下,对GH169、GH202、GH586三种航天用典型合金进行了抗燃烧性能测试和特征研究,采用光镜、扫描电镜对燃烧产物的组织进行了分析。结果表明,合金在试验条件下均被点燃,其抗燃烧能力和燃烧持续时间从高到低依次为GH202、GH586、GH169;合金的燃烧产物主要由熔化团聚体和渣料组成,且燃烧后形成了大量的空洞组织,燃烧试样形貌由疏松氧化层、熔化层和基体构成;合金具有低的燃烧热以及在富氧条件下形成相对致密的氧化膜(如Al2O3,Cr2O3)均能改善其抗燃烧性能。     

Surface modification of polyester fabrics for inkjet printing with atmospheric-pressure air/Ar plasma

Without any preprocessing, polyester fabric has a lower ability to hold on water and inks due to the smooth morphology and chemistry property of polyester fibers. Therefore, patterns directly printed with pigment inks have poor color yields and bleed easily. Plasma surface treatment of polyester fabrics was carried out in composite atmosphere with air and 10% Ar under different experimental conditions. After plasma treatment the samples were printed with pigment inks. The results show that surface-modified polyester fabrics exhibited enhanced color yields and excellent pattern sharpness. SEM and XPS analyses indicated that this improved color performance was mainly contributed by not only the etching effect but also oxygen-containing polar groups induced onto fiber surfaces through plasma treatment. Thereby the surface modification of polyester fabrics using air/Ar plasma offers a potential way to fabric pretreatment for pigment inkjet printing with the advantages of environmental friendly and energy saving over traditional pretreatment methods.     

碳含量对Ti-Al-C系燃烧合成Ti3AlC2粉体的影响

实验表明在Ti—Al—C体系中，C含量对燃烧合成Ti3A1C2影响很大：C含量(原子分数)较低时(22．64％-28．07％)，燃烧产物主要物相为Ti2A1C；C含量较高时(29．31％-32．79％)，燃烧产物主要物相为Ti3A1C2．Ti3A1C2的燃烧合成反应温度高于Ti2A1C的燃烧温度，Ti3A1C2的生成量随燃烧反应温度升高近似呈对称分布．从反应物原料摩尔配比和热力学原理角度，探讨了不同C含量对燃烧产物组成的影响机理．     

Thermal Behavior of Polyester Composites Reinforced with Green Sugarcane Bagasse Fiber

Natural fibers such as those from sugarcane bagasse may be obtained as industrial waste products. These fibers have recently been investigated as low-cost reinforcements in composites for engineering applications, some of which may require exposure to temperatures above ambient. In the present work, fibers extracted from sugarcane bagasse were used at up to 30 vol.% as reinforcement in polyester-matrix composites. The thermal behavior of these composites was investigated by thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) as well as dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). TGA/DTG results indicated similar limits of thermal stability at about 200°C for the neat polyester and the bagasse fiber composites. The thermal degradation peak at around 370°C was also similar, being attributed mainly to polyester. DSC analysis revealed that bagasse fiber incorporation caused only a minor change in the glass-transition temperature. On the contrary, DMA parameters revealed notable changes attributed to effect of the bagasse fibers on the viscous stiffness and damping capacity of the polyester.     

Resistive Switching Behavior of Hafnium Oxide Thin Film Grown by Magnetron Sputtering

采用磁控溅射法,以ITO/Glass为衬底,制备了具有电阻转变特性的HfO2薄膜。X射线光电子能谱(XPS)分析发现,薄膜中的Hf、O元素不成化学计量比,薄膜中可能存在大量氧空位。电学测试结果表明,HfO2薄膜表现出明显的双极电阻转变特性,并且表现出良好的可靠性(室温下可重复测试102次以上)和稳定的保持性能(0.5 V偏压下保持104 s以上),高低阻态比值达到104。基于XPS以及电学分析,薄膜的导电过程可用与氧空位相关的空间电荷限制电流模型解释。     

Electrical,structural, photoluminescence and optical properties of p-type conducting,antimony-doped SnO2 thin films

P-type transparent conducting antimony-doped tin oxide (ATO) films were successfully fabricated on quartz glass substrates by radio-frequency magnetron sputtering using a 20 mol.% Sb-doped SnO₂ ceramic target. The deposited films were annealed at different temperatures for different durations. Hall effect results indicated that 973 K was the optimum annealing temperature to get p-type ATO films with the highest hole concentration (5.83 × 10¹⁹ cm^–3). X-ray diffraction studies indicated that the preferred (1 0 1) orientation favored the formation of p-type conducting films. Photoluminescence spectra showed an intense UV luminescence peak near 362 nm resulting from the band-edge exciton transition observed for p-type ATO films. UV–visible transmission spectra showed that p-type ATO films had high transparence. In addition, p-type conductivity was also confirmed by the non-linear characteristics of a p-type ATO/n-type ATO structure; the diode structure has an optical transmission of ～60–85% in the visible light range.