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971.
972.
Sydney C. K. Chu 《The Journal of the Operational Research Society》1989,40(9):771-778
This paper reports the actual implementation of a location-allocation study, which is one aspect of the overall Passive Cooling (Thailand) Project conducted in Northern Thailand since 1985. The goal has been to generate decision supports for ‘optimal’ placements of cooling facilities and the assignment of sites to these facilities as part of the post-harvest handling-chain operation of agricultural products. The basic questions addressed in this work are the issues of how many facilities to set up and where to locate them for maximum utility. Our selected approach is to use discrete location-allocation modelling, as, among other reasons, the problem at hand has a most natural network setting. Direct methods as well as efficient heuristics are examined, and sample numerical results are reported as illustrations of the continual implementation. 相似文献
973.
974.
975.
976.
Electrochromic effects are observed by employing a single mixed ionic and electronic conducting layer in-between two transparent
electronic leads. Besides the simplicity of the arrangement, the advantage is the displacement of ions only within one phase
rather than across phase boundaries as required by conventional devices.
The applied voltage controls the compositions at the two interfaces according to Nernst's law independent of ions being majority
or minority charge carriers. Appropriate materials are intrinsic conductors in the unpolarized transparent state which become
n-type and p-type conducting at the negative and positive electrode side, respectively. Several materials have been investigated,
such as lithiated tungsten oxide and lithium/tantalum co-doped tungsten oxide.
Paper presented at the 1st Euroconference on Solid State Ionics, Zakynthos, Greece, 11–18 September 1994. 相似文献
977.
George Fytas Thomas Dorfmuller Benjamin Chu 《Journal of Polymer Science.Polymer Physics》1984,22(8):1471-1481
We report polarized photon correlation measurements of bulk poly(phenylmethyl siloxane) (PPMS) with a molecular weight of about 2500 at different pressures from 1 to 1750 bar and temperatures between 269 and 308 K. In the Frequency range accessible by present-day digital correlators, the time correlation function can measure a slow q2-dependent diffusional process due to local concentration fluctuations and a fast α-mode structural relaxation process. The mean characteristic times of the two processes approach each other at low temperatures and high pressures, in contrast to the behavior of the α- and β-relaxation times. We should be cautious in relating the mean characteristic times for the structural relaxation process obtained by different experimental techniques, such as Brillouin scattering and photon correlation spectroscopy, because of the differnces in the probe emphasis and the extremely broad frequency distribution of such relaxation processes. 相似文献
978.
979.
X. Zhang S.S. Chu J.R. Ho C.P. Grigoropoulos 《Applied Physics A: Materials Science & Processing》1997,64(6):545-552
Received: 21 June 1996/Accepted: 9 December 1996 相似文献
980.
大孔硅胶反相色谱填料的高温溶剂法合成及其在蛋白质分离上的应用 总被引:3,自引:0,他引:3
报道利用高温溶剂法在Sinopak-S大孔硅胶上键合十八烷基,得到阿用于蛋白质分离的高效反相色谱填料,合成时间缩短为3-5h。用萘,萘,菲及苯胺评价了该反相柱,其理论塔板数达每米3到5万,能有效地用于蛋白和多肽混合物的分离。 相似文献