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71.
穆紫 《国外塑料》2002,20(4):14-16
详细介绍了一种新型装饰工艺-模内贴箔工艺的自动化过程及生产要求。  相似文献   
72.
Supported vanadium-containing catalysts were prepared by impregnation of Al-pillared clays with NaVO3 precursor aqueous solutions. A montmorillonite and a saponite, both natural as well as previously pillared with Al13-Keggin polycations, were used as supports, being impregnated with solutions of the precursor by means of the incipient wetness technique. The layered structure of the supports is maintained after impregnation, and even after calcination of the impregnated solids at 500 °C, although with a significant worsening of the textural properties of the solids, in particular, a loss of specific surface area. Three crystalline vanadium-containing phases were identified in the impregnated solids, namely, NaV3O8, AlVO4 and V2O5 (shcherbinaite). The reduction of these phases to V3+ species was observed as wide processes in the 450–750 °C range, all of them centred at ca. 600 °C.  相似文献   
73.
Comments that the paper by Liu and Yao (see ibid., vol.40, no.1, p.190, 1992) presented an efficient algorithm for spectral decomposition, but the parallel algorithm and architecture for the Hessenberg reduction has a problem. The matrix obtained from the unitary similarity transformation is not necessarily a Hessenberg matrix. The authors reply that the Hessenberg reduction described is not in the Hessenberg form. Only the first column is in its proper form. There are many ways to overcome such a problem. One simple way is to use the multiphase rectangular systolic array  相似文献   
74.
75.
东濮凹陷泥岩裂缝油气藏形成条件及分布特点   总被引:8,自引:1,他引:7  
结合东濮凹陷地质特点,探讨研究了东濮凹陷泥岩裂缝油气藏形成的地质条件,东濮凹陷油气源岩发育,泥岩裂缝发育,泥岩裂缝油气成藏有着较好的成藏条件,是一种新的油气藏类型,有着良好的勘探前景,同时对泥岩裂缝油气藏在东濮凹陷的分布特点进行了研究。指出高压区及超高压区,盐岩分布区,构造转换带是寻找这类油气藏的有利地区。层系上,沙三^2-4是勘探这类油气藏的有利层系,一些稳定的泥,页岩标志层也是寻找这类油气藏的有利层段。  相似文献   
76.
浙江省已经成为我国最大的泵产品制造省份,温州、台州、杭州是浙江省泵制造业的三个生产基地,永嘉还被中通协授予“中国泵阀之乡”的称号,然而许多浙江籍泵企业领导都有这样的感慨;企业的初期发展非常快,但发展到一定规模后,速度就停止下来了,专家牟介刚一直关注浙江泵业的发展,在本文中,分析了浙江泵业普遍存在的深层不足,并给出了今后如何发展的措施建议,值得浙江的泵业企业家们关注。  相似文献   
77.
78.
Oxygenated fuels increase fuel consumption due to their low enthalpy of combustion; however, their high antiknock index renders them suitable for use in engines with a high compression rate, increasing their thermal yield. This study evaluated the performance of biorenewable oxygenated fuels (ethanol and isoamyl alcohol) and partially renewable fuels (ETBE: ethyl tert-butyl ether, TAEE: tert-amyl ethyl ether and di-TAE: di-tert-amyl ether) with high degree of purity and in mixtures with automotive gasoline, based on tests with Otto cycle engines. Among the oxygenated fuels evaluated here, di-TAE was found to present the best characteristics of performance, both individually and in mixtures with gasoline.  相似文献   
79.
The nonisothermal crystallization kinetics of a metallocene-made isotactic polypropylene (m-iPP) and its compounds with 0.1 wt % and 0.3 wt % of a sorbitol derivative [1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol (DMDBS); an α nucleator] were investigated by differential scanning calorimetry at different cooling rates from the melt. The nucleation efficiency was proved by a significant increase in the crystallization temperatures (accompanied by a slight augmentation of the degree of crystallinity and a decrease in the crystal sizes). This increase in the crystallization temperatures led to higher amounts of fractional content in the γ polymorph, even though DMDBS was supposed to be a nucleator for the α form. The Avrami and Ozawa methods effectively described only the early stage of crystallization, whereas a combined Avrami–Ozawa method was valid for the whole crystallization process. The values of the exponent for this method decreased for nucleated samples in the later stage of crystallization, especially in the case of m-iPP with 0.3 wt % DMDBS added (m-iPP03). The activation energy of the process and the surface free energy were also estimated. The production of considerable proportions of the γ polymorph in m-iPP03 corresponded to higher values of the activation energy and lower values of the surface free energy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
80.
The Humanitarian Engineering initiative, sponsored by the William and Flora Hewlett Foundation, at the Colorado School of Mines, is creating a program that will support engineering students in understanding their responsibility for solving community development problems that exist throughout the world. As part of this effort, data has been collected on faculty and student attitudes using the ‘Community Service Attitudes Scale,” developed and validated by Shiarella, McCarthy, and Tucker. During the fall 2004, 78 students and 34 faculty members responded to this instrument. Statistically significant differences were found between the attitudes of students and faculty, males and females, and among different age groupings with respect to service activities. A general finding was that faculty displayed better attitudes toward community service than the students.  相似文献   
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