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1.
During the day, there are considerable variations in the climatic factors prevailing in these regions. This is especially so during the 24-hour daily cycle of the long, hot and dry summer (mid-May to midOctober). Such climatic conditions have had a considerable impact on the daily living pattern of family life in the same season, particularly in the urban areas. During the same 24-hour cycle, they have compelled the inhabitants to shift their living activities both vertically in section and horizontally in plan; they do this in pursuit of more acceptable, if not, desirable internal thermal environmental ambience.  相似文献   
2.
黄河下游滩区居民对安全的心理需求   总被引:1,自引:0,他引:1  
黄河下游滩区居民对自身安全的需求非常强烈,具体表现在以下3个方面:对房屋采取垫高房台等安全措施,出于安全的原因愿意搬离现居住地,较高生育率与偏好男孩。他们建立在安全需求上的相应行为,增大了生活成本,影响着他们生存发展的空间,进而制约着滩区社会经济的发展。  相似文献   
3.
通过对西安绿色康居小区规划设计的实例分析,阐明了小康型住宅区的标准和要求,在旧城住宅区改造中的落实和运用,试图探索下一世纪旧城住宅区的改造之路.  相似文献   
4.
One of the most promising applications of encapsulated living cells is their use as protected transplanted tissue into the human body. A suitable system for the protection of living cells is the use of nano‐ or microcapsules of polyelectrolytes. These shells can be deposited easily on top of the cells by means of a layer‐by‐layer technique. An interesting feature of the capsules is the possibility to control their properties on a nanometre level, tuning their wall texture via the preparation conditions. Here we introduce a model system to test the protection ability of polyelectrolyte capsules. Common bakery yeast cells were encapsulated. They were coated with a fluorescently labelled shell at conditions known to guarantee cell survival, and the cell interior was stained with DAPI. The protozoan Paramecium primaurelia was incubated with this double‐stained living yeast and visualized by means of two‐photon excitation fluorescence microscopy. Cross‐sections of the dye‐stained material as well as autofluorescence of the fixed protozoan allowed us to follow the digestion of the coated yeast with time. Our investigation reveals that capsules prepared under these deposition conditions are permeable to lysosomal enzymes, leading to degradation of the yeast inside the intact capsules. Our preliminary results indicate the suitability of the introduced model as a test system of this permeability.  相似文献   
5.
辽宁省城镇居民生活用水定额   总被引:1,自引:0,他引:1  
本文分析了城镇居民生活用水的特点,介绍了辽宁省城镇居民生活用水定额制定的原则、方法。通过对全省县级以上城镇居民生活用水情况的调查,制定适合辽宁省实际情况的城镇居民生活用水定额。  相似文献   
6.
BACKGROUND: Two peat biofilters were used for the removal of toluene from air for one year. One biofilter was fed with pure toluene and the other received 1:1 (by weight) ethyl acetate:toluene mixture. RESULTS: The biofilters were operated under continuous loading: the toluene inlet load (IL) at which 80% removal occurred was 116 g m?3 h?1 at 57 s gas residence time. Maximum elimination capacity of 360 g m?3 h?1 was obtained at an IL of 745 g m?3 h?1. The elimination of toluene was inhibited by the presence of ethyl acetate. Intermittent loading, with pollutants supplied for 16 h/day, 5 days/week, did not significantly affect the removal efficiency (RE). Biomass was fully activated in 2 h after night closures, but 6 h were required to recover RE after weekend closures. Live cell density remained relatively constant over the operational period, while the dead cell fraction increased. Finally, a 15 day starvation period was applied and operation then re‐started. Performance was restored with similar re‐acclimatization period to that after weekend closures, and a reduction in dead cell fraction was observed. CONCLUSION: This study demonstrates the capacity of the system to handle intermittent loading conditions that are common in industrial practices, including long‐term starvation. Copyright © 2008 Society of Chemical Industry  相似文献   
7.
In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio‐polymeric microthread from which active biological scaffolds were fabricated (Townsend‐Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post‐processed cells as composite threads and scaffolds are being investigated in‐depth at a cellular level to establish if the processing methodology has any affect on the cellular make‐up. We now demonstrate a competing non‐electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio‐threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post‐processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
8.
甲基丙烯酸乙酯的"活性"/可控阴离子聚合   总被引:1,自引:0,他引:1  
采用空间位阻大的引发剂1,1-二苯基己基锂(DPHLi),添加新型络合剂LiClO4,在-5℃,实现了活性阴离子聚合反应,获得分子量分布为1.05的单分散聚甲基丙烯酸乙酯(PEMA)。  相似文献   
9.
Summary: A semi‐batch process using nitroxide mediated polymerization, was explored for the design of low molecular weight solvent‐borne coatings, typical of those used in the automotive industry. While living radical polymerization (LRP) offers many advantages in the control of polymer chain microstructure that may confer important physical and chemical property benefits to coatings, adapting LRP to a semi‐batch process poses significant challenges in the design and operation of the process. Using styrene monomer, various two‐component initiating systems (free radical initiator, 4‐hydroxy‐TEMPO) were studied to understand the effects of different initiators on the course of polymerization. In addition, an alkoxyamine was synthesized and used as the initiating source. The initiators Luperox 7M75 and Luperox 231 give higher polymerization rates and reasonable control over polymerization, while benzoyl peroxide (BPO), Vazo 67, and the alkoxyamine are less effective. The number of polymer chains in the final product is always less than the theoretical value, reflecting poor initiation efficiency, probably resulting from undesirable termination reactions that become important due to the nature of the semi‐batch process. Adding camphorsulfonic acid (CSA) or charging initiator concurrently with monomer during semi‐batch feed, can increase the polymerization rate while maintaining the living character of the polymerization. The copolymerization of styrene and butyl acrylate is also shown to exhibit living character.

Schematic representation of the exchange reaction to produce N‐TEMPO capped polymer chains.  相似文献   

10.
活性自由基乳液聚合是一个非常新的研究领域。介绍了目前活性自由基乳液聚合领域的3种常用的方法及应用这些方法进行乳液聚合的研究进展,包括:原子转移自由基聚合(ATRP),氮氧调节自由基聚合(NMP)和可逆加成-断裂链转移自由基聚合(RAFT)。  相似文献   
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