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941.
This paper investigates the relationship between neighborhood cohesion and organization and class in Hong Kong. It draws on a survey of 1200 face-to-face interviews in an up-market private housing estate on Hong Kong Island, a large, neither rich nor poor public housing estate in the New Territories and a mixed-use, low-income inner-city neighborhood in Kowloon. Four indexes measure interneighborhood and intraneighborhood differences—namely, attraction to neighborhood, neighboring and psychological sense of community adapted from the Buckner scale of social cohesion, and social organization developed by the author. There are significant differences between the neighborhoods. However, these differences are not duplicated between occupation-defined class within the neighborhoods, although there are some differences based on self-defined social class. The likely explanation lies in the character of the three neighborhoods, government policy, effect of private housing management and the low level of spatial differentiation by income across the city.  相似文献   
942.
聚合物反相乳液深部调驱技术试验研究   总被引:1,自引:0,他引:1  
常温条件下聚合物反相乳液调驱剂是油包水的稳定乳液,根据孤岛油藏特点对该调驱剂进行了适应性室内评价,模拟地层条件下转相成胶时间大于3d,单管岩心封堵试验的阻力系数为10.4,三管模拟注聚后调驱试验最终提高采收率13%,说明该体系可以到达岩心深部发挥调驱作用.在6个井组实施了反相乳液调驱体系调驱后,注水井油压平均上升了1.8MPa,对应油井见效期内含水平均下降了3.4%,平均单井增产原油377t.  相似文献   
943.
944.
The porosity and pore size distribution of three-dimensional scaffolds have direct implications on their biomedical applications (tissue engineering, drug delivery, and wound dressing). Accordingly, in this paper, a fast, facile, and conservative method relying on low-field nuclear magnetic resonance (LF-NMR) for the evaluation of mean pore size and pore size distribution of polymeric scaffolds is reported. The applicability of the technique is demonstrated on poly-L-lactic acid scaffolds fabricated using the thermal induced phase separation. Results obtained through LF-NMR are successfully compared to scanning electron microscope and X-ray microcomputed tomography micrographs.  相似文献   
945.
This study investigated the influence of surface‐inactive carbohydrates on association characteristics of amphiphilic mung bean protein hydrolysate (MPH) and asiatic acid (AA) in aqueous suspension (11.72–11.94% total solids). The carbohydrates investigated were trehalose, maltodextrin, mixed trehalose–maltodextrin and mixed maltodextrin–starch. The presence of low‐molecular‐weight carbohydrates enhanced micellisation of AA to form micrometre‐sized particles due to depletion flocculation. Nonetheless, the presence of starch retained the submicrometre size of AA. In contrast, the presence of starch enhanced self‐association of MPH via segregative phase separation. However, the mixed suspensions containing MPH, AA and carbohydrate in a ratio of 1:0–0.072:2.34, respectively, retained particle sizes of around 300 nm regardless of the carbohydrate used. It was found that the MPH–AA co‐aggregates were stable against the osmotic effect of carbohydrates. The results suggest that carbohydrates regulated the aggregate size and surface hydrophobic region of MPH and MPH–AA by controlling surface‐induced aggregation.  相似文献   
946.
947.
948.
A new algorithm for the calculation of monomer partitioning in emulsion copolymer systems is presented. The algorithm can be applied both to monodisperse and polydisperse systems and the outputs of the algorithm include the distribution of the volume fractions of the monomers according to the particle size distribution, the volume fractions of the monomers in the monomer droplets, and the aqueous phase and the total volumes of all the phases in the system. The algorithm can handle both Interval II and Interval III conditions, using the same set of equations. This results in substantial computer time savings during the simulation of emulsion copolymerization systems. Examples of applications are given. © 1994 John Wiley & Sons, Inc.  相似文献   
949.
950.
The endogenous cannabinoid ligand anandamide (arachidonylethanolamide) inhibited the intestinal passage of a charcoal meal when administered s.c. in mice at doses ranging from 0.1 to 50 mg/kg. This effect was prevented by the cannabinoid CB1 receptor antagonist SR141716A [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-me thyl-1H-pyrazole-3-carboxamide x HCl] (1 mg/kg s.c.), but it was not affected by the anandamide transport inhibitor, N-(4-hydroxyphenyl) arachidonylethanolamide (AM404) (50 mg/kg, s.c.). The results indicate that anandamide modulates intestinal motility in mice by activating cannabinoid CB1 receptors. They also suggest that anandamide transport, which was previously shown to participate in terminating neural and vascular responses to anandamide, does not contribute to anandamide inactivation in intestinal tissue.  相似文献   
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