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1.
M. Kwapi&#x  ska  I. Zbici&#x  ski 《Drying Technology》2005,23(8):1653-1665
The effect of drying and atomization conditions on the physical properties of powders for agglomerate-like materials and skin-forming material are studied in this article. A neural model is used for powder bulk and tapped density predictions.  相似文献   
2.
Thermal history and solute precipitation behavior of suspended solution droplets of sodium chloride (NaCl), magnesium sulphate (MgSO4), and zirconium hydroxychloride (ZrO(OH)Cl) evaporating at atmospheric and reduced pressures are studied. Experimental measurements on the variation of droplet diameter, solution concentration, and temperature during the evaporation period are presented and discussed. The results of solute precipitation behavior in solution droplets observed under an optical microscope are displayed and discussed. Results indicate that reducing the pressure (∼ 33 kPa) results in a change in the solution droplet evaporation rate, but the thermal histories of a particular solution droplet are similar at the atmospheric and reduced pressures. At atmospheric and reduced pressures used in this study, the d2 law for solution droplets is valid at early stages of the evaporation and before the solute precipitation initiates. Drying of MgSO4 and ZrO(OH)Cl solution droplets results in the formation of spherical particles, whereas drying of spherical NaCl solution droplets results in the formation of cubic particles.  相似文献   
3.
介绍了粉末涂料的几种涂装方法及其原理、特点、应用范围和进展情况,重点介绍了静电粉末涂装方法。  相似文献   
4.
利用自行制做的试验装置,以配制出的强腐蚀环境土为介质,对非预应力锚索和预应力锚索的裸筋以及对有注浆缺陷的锚索试件进行了腐蚀试验,从外观腐蚀状况和腐蚀后的钢绞线力学性能的改变特性进行了研究.结果表明:从外观上看,预应力锚索试件的腐蚀程度总体上比非预应力试件的腐蚀程度要重,含注浆缺陷的锚索试件的腐蚀程度比裸筋的腐蚀程度要重...  相似文献   
5.
目前,我国刑事被害人的权利保护状况已得到了很大的改善,然而,在执法实践中公安司法机关对被害人权利的保护仍存有许多缺陷,包括立案、侦查直至审判、执行等诉讼环节都还有系列需改进之处。针对执法之现状,我们必须采取有效措施去加以完善。  相似文献   
6.
The transport and dosage of granular materials are an important part of Process Engineering. Thereby, the food, chemical, pharmaceutical and coating industries set high demands on the transport and dosage performances of the used plants. In this context, Ultrasound Process Technology in the past years has developed itself into an attractive alternative compared to presently used classical technologies.

This paper describes the application of ultrasonic progressive waves in a powder-feeding device. The use of a specific pipe material with appropriate damping characteristics allows to generate a progressive wave using a single piezoelectric actuator. Small objects can be carried along the surface of a pipe by the elliptic motion at the surface, which is the result of a flexural progressive wave. The operational principle is the same as in travelling wave ultrasonic motors.

It was experimentally confirmed that the device can be used for feeding and supplying small amounts of powder. The powder-fed performance, however, strongly depends on environmental conditions, so that a control of the system is required. Construction and characteristics of a trial device are shown.  相似文献   

7.
TiO2 fims have been deposited on glass substrates using DC reactive magnetron sputtering at different oxygen partial pressures from 0. 10 Pa.to 0.65 Pa. The transmittance (UV-vis) and photoluminescence (PL) spectra of the films were recorded. The results of the UV-vis spectra show that the deposition rate of the films decreased at oxygen partial pressure P(O2)≥0.15 Pa, the band gap increased from 3.48 eV to 3.68eV for direct transition and from 3.27 eV to 3.34 eV for indirect transition with increasing the oxygen partial pressure. The PL spectra show convincingly that the transition for films was indirect, and there were some oxygen defect energy levels at the band gap of the films. With increasing the O2 partial pressure, the defect energy levels decreased. For the films sputtered at 0.35 and 0.65 Pa there were two defect energy levels at 2.63 eV and 2.41 eV, corresponding to 0.72 eV and 0.94 eV below the conduction band for a band gap of 3.35 eV, respectively. For the films sputtered at 0.10 Pa and 0.15 Pa, there was an energy band formed between 3.12 eV and 2.06 eV, corresponding to 0.23 eV and 1.29 eV below the conduction band. ZHAO Qing-nan : Born in 1963 Funded by Natural Science Foundation of Hubei Province, China.  相似文献   
8.
详细介绍了在斜面焊口超声波探伤中采用声程调节扫描比例进行缺陷定位的计算方法,并给出了计算公式。  相似文献   
9.
任选 《山西冶金》2011,34(2):25-26,52
通过对宽厚钢板探伤不格合的缺陷分析,提出探伤不格合产生的主要原因是浇注过程中存在非正常减流、中心疏松和外来夹杂.于是对浇注过程作了改进,使宽厚钢板探伤合格率提高.  相似文献   
10.
In the present investigation in order to promote TiO2 pellet structure and its photocatalytic activity, two new precursors were synthesized in the powder and sol forms, using sol–gel method with precipitation of TiCl4. Since TiO2 pellets are normally synthesized by the commercial TiO2 powder (DegussaP25), in this investigation and in the first step a new synthesized TiO2 powder was produced and compared with DegussaP25. Subsequently, two types of pellet were made by the new synthesized powder and titania sol. The characterization of the synthesized TiO2 powder and pellet were performed by XRD, FT-IR, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The result showed that by the new procedure utilized here, without using any additive not only the surface area of the produced TiO2 powder has been increased, but also the crystalline phase is completely in the anatase form. It was also found that the synthesized pellets by the sol precursor had better morphological structure than the synthesized pellets by theTiO2 powder (either DegussaP25 or new synthesized powder). Ultimately, in order to evaluate photocatalytic activity of TiO2 powders and pellet, degradation of RhodamineB was tested.  相似文献   
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