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61.
62.
对我公司硝铵装置降膜蒸发工序存在的问题进行分析 ,并通过技术改进 ,使干燥洗涤液全部返回系统 ,造粒塔粘塔问题得到缓解 ,取得可观的经济效益和环保效益 相似文献
63.
本文叙述了用PHI—550型给定的俄歇电子能谱(AES)研究了一种新的、性能优异的二次电子发射材料——MgO薄膜。薄膜由Ag—Mg合金经特殊高温激活工艺处理而成。以前人们对这种薄膜内部的各种元素的化学状态以及纵向原子浓度的分布状态一直不太清楚,本实验的成功证明了俄歇(Auger)电子能谱是研究这种薄膜的一种非常合适的实验方法。从实验结果中,我们发现如下几点 1.激活后,Mg和O原子的化学状态发生了显著的变化。 2.激活后,Mg、O和Ag原子的纵深分布也发生了显著的变化。 3.Mg原子氧化不充分,为了改进这一缺点,我们发明了一种新工艺。 4.使用新工艺激活,Mg原子可获充分氧化。 相似文献
64.
The excess water film theory and the properties of flocs are integrated to examine the effect of the polycarboxylate-type superplasticizer on the paste fluidity.The theory states that excess water can surround the flocs rather than the particles and that the cell consists of a floc and a superficial water film.Experiments on limestone powder pastes were conducted to verify the theory.The superplasticizer dosage(sp%)and the water–powder ratio by volume(Vw/Vp)were systematically varied.A sedimentation balance method was used to measure the size distribution of the flocs in the limestone powder pastes.The water film thickness(WFT)of flocs was then calculated and shown to determine the paste fluidity.Based on this WFT of flocs,the effect of the sp on the paste fluidity was determined and then compared with the effect of water. 相似文献
65.
A comprehensive survey has been carried out to establish which sun-screen agents are used by the cosmetics industry in Holland. During 1978, some 200 cosmetic sun preparations, composed of forty-eight brands, were purchased and analysed to determine which u.v. absorbing compounds were present. Most of those found were identified and quantified by means of thin layer chromatography and u.v. spectrometry. A basis for this work was the proposal by the European Cosmetic Manufacturers to produce a positive list of u.v. absorbers. It was felt that by carrying out this survey, some priority could be placed on the most popular materials used by the industry. When comparing those found with the European list of u.v. absorbers 1978, only twenty-four of the sixty compounds listed could be identified in the samples. The six most frequently used were found to be:
- 1 2-Ethylhexyl.p.methoxycinnamate (nineteen brands).
- 2 2-Phenylbenzimidazole.5-sulphonic acid (eleven brands).
- 3 2-Ethoxyethyl.p.methoxycinnamate (nine brands).
- 4 3 (4′Methylbenzylidene)D,D,L-camphor (seven brands).
- 5 3-Benzylidene.D,L-camphor (six brands).
- 6 2-Hydroxy.4-methoxy.benzophenone (six brands).
66.
环保高性能防腐涂料驱动未来市场 总被引:5,自引:0,他引:5
介绍了防腐涂料的新品种和防腐体系的选择,指出了我国防腐涂料的发展趋势。 相似文献
67.
Zinc telluride thin films have been grown at room temperature and higher temperature substrates by thermal evaporation technique
in a vacuum of 10-6 torr. A main peak in the photocurrent is observed at 781 nm (1.58 eV) with two lower amplitude peaks on the lower wavelength
side and one on higher wavelength side. The evaluated thermal activation energy is found to correspond well with the main
spectral peak. From these studies it can be inferred that temperatures up to 453 K is still in the extrinsic conductivity
region of the studied ZnTe thin films.
The paper was presented at the 6th Asian Thermophysical Properties Conference (6th ATPC), held at Gauhati University, during
8–11 October 2001. 相似文献
68.
Sang-Hoon Shin Sung-Dae Kim Jong-Ha Moon Jin-Hyeok Kim 《Journal of Electroceramics》2006,17(2-4):1097-1101
Er3+/Pr3+ co-doped soda-lime glass thin films have been fabricated using RF magnetron sputtering method and their structural and optical
properties have been studied. Deposition rate, crystallinity, and composition of glass thin films were investigated by scanning
electron microscopy, transmission electron microscopy, and electron probe micro area analysis. Refractive index, birefringence
and binding characteristics have been investigated using a prism coupler and X-ray photoelectron spectroscopy. Er3+/Pr3+ co-doped soda lime glass thin films were prepared by changing substrate temperature (room temp. ∼550∘C), RF power (90 W–130 W), and Ar/O2 gas flow ratio at processing pressure of 4 mTorr. Glass thin films could be obtained at the optimized processing condition
at 350∘C, RF power of 130 W, and gas flow of Ar:O2 = 40:0 with maximum deposition rate of 1.6 μm/h. Refractive index and birefringence increased from 1.5614 to 1.5838 and from
0.000154 to 0.000552, respectively, as the content of Pr3+ increased. Binding energy of Pr3d also increased as the content of Pr3+ increased. 相似文献
69.
A. Wisitsoraat A. Tuantranont C. Thanachayanont V. Patthanasettakul P. Singjai 《Journal of Electroceramics》2006,17(1):45-49
Carbon nanotube (CNT) is a useful material for gas-sensing applications because of its high surface to volume ratio structure.
In this work, multi-wall CNTs are incorporated into tin oxide thin film by means of powder mixing and electron beam evaporation
and the enhancement of gas-sensing properties is presented. The CNTs were combined with SnO2powder with varying concentration in the range of 0.25–5% by weight and electron beam evaporated onto glass substrates. From
AFM and TEM characterization, CNT inclusion in SnO2thin film results in the production of circular cone protrusions of CNT clusters or single tube coated with SnO2layer. Experimental results indicate that the sensitivity to ethanol of SnO2thin film increases by the factors of 3 to 7, and the response time and recovery time were reduced by the factors of 2 or
more with CNT inclusion. However, if the CNT concentration is too high, the sensitivity is decreased. Moreover, the CNT doped
film can operate with good sensitivity and stability at a relatively low temperature of 250–300∘C. The improved gas-sensing properties should be attributed to the increasing of surface adsorption area of metal oxide produced
by CNT protrusion. 相似文献
70.