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931.
本文综述了《建筑机电设备开放式通信协议研究——ioDeNet》项目的产生、研发、成果及应用推广的过程,并对其技术原理、实施方案、优越性、先进性、创新性及发展前景和计划进行了介绍。  相似文献   
932.
本文综述了《建筑机电设备开放式通信协议研究——iopeNet》项目的产生、研发、成果及应用推广的过程,并对其技术原理、实施方案、优越性、先进性、创新性及发展前景和计划进行了介绍。  相似文献   
933.
A novel reactive hot melt adhesive was prepared by coating an epoxy resin on maleic anhydride grafted polyethylene (MAPE) powder. This adhesive had markedly improved adhesion power compared with pristine MAPE powder, which is normally used as a hot melt adhesive. The generation of an ester linkage by the reaction between the anhydride group of MAPE and the hydroxyl group of epoxy resin, during the bonding operation at 190°C with the pressure of 22 MPa for 30 min, was confirmed from the FTIR spectra. The bond strength was further improved by a small amount of 1‐methylimidazole, which accelerated the esterification reaction. When the epoxy resin was coated on hydrated MAPE, in which the anhydride group of MAPE was converted into carboxylic acid group by the reaction with water, the esterification reaction was much faster than that of pristine MAPE, and consequently, the bond strength of the adhesive was much higher than that of pristine MAPE coated with epoxy resin. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
934.
A new approach for improving the wear performances of nylon 6 (PA6)/clay nanocomposites was examined in this study. Two hybrid nanocomposites were prepared by melt blending a thermotropic liquid crystalline polymer (TLCP) and a well‐dispersed PA6/clay nanocomposite, but with and without the incorporation of maleic‐anhydride grafted polypropylene (MAPP) as compatibilizer. The addition of MAPP improved the compatibility between TLCP and matrix and thus enhanced the fibrillation of dispersed TLCP phase. Wear‐testing results revealed that the wear resistance of the compatibilized hybrid nanocomposite could be improved effectively, as indicated by the low values of specific wear rate and frictional coefficient, especially under high‐normal load (i.e., 80 N). Based on the characterization on the worn damage and the debris, it was suggested that abrasive wear was the main‐damage mechanism for all the materials under investigation, except for the compatibilized hybrid nanocomposite. For this system, the wear damage was caused by a combination of abrasive and adhesive wearing because of the formation of transfer film on the counter pin surface from the wear debris. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers  相似文献   
935.
It is important to properly understand and calculate the distributions of the heat flux and the heat transfer coefficient in a furnace for designing a circulating fluidized bed (CFB) boiler, especially for one with supercritical parameters. An experimental study of the heat transfer in a commercial 300 MWe CFB boiler was conducted in this work. The heat flux from the bed to the waterwall was measured by a heat flux meter at four different heights. The influence of suspension density and bed temperature was analyzed by measuring the pressure profile and temperature profile in the furnace. In addition a numerical modeling study on the two phase flow in the furnace was carried out. The results indicate that the density of the solids suspension was non-uniform in the cross section at a certain height, and decreased gradually with increasing furnace height. Consequently, the distribution of heat flux in the horizontal plane was non-uniform and decreased along the height of the furnace. The heat flux showed a decreasing trend near the center.  相似文献   
936.
Characteristics of heat transfer were investigated in pressurized slurry bubble column reactors whose diameter was either 0.051, 0.076, 0.102 or 0.152 m (ID) and 1.5 m in height, respectively. Effects of gas velocity (U G ), solid contents (S C ), pressure (P), liquid viscosity (μ L ) and column diameter (D) on the heat transfer coefficient (h) between the immersed vertical heater and the column were determined. Multiple effects such as UG and D, P and D, μ L and D, and S C and D on the value of heat transfer coefficient were discussed. Temperature fluctuations were also measured and analyzed by adapting chaos theory, which was used to explain the effects of operating variables on the heat transfer in the column. The heat transfer coefficient increased with increasing gas velocity, pressure or solid content in the slurry phase, but decreased with increasing liquid viscosity or column diameter. The decrease trend of h with increasing column diameter was somewhat sensitive when the gas velocity was relatively high (U G ⩾12 cm/s). The effects of column diameter on the h value became almost linear when the operating pressure (P=4−10 kg f /cm2), liquid viscosity (μ L =20−38 mPa·s) or solid content in the slurry phase (S C =10−20 wt%) was relatively high and gas velocity was relatively low, within these experimental conditions. The heat transfer coefficient was well correlated in terms of dimensionless groups as well as operating variables.  相似文献   
937.
近年来,由于REACH制度的实施,化学品贸易受到极大的限制。REACH制度要求进入欧盟的化学品必须进行注册,且注册出具的数据必须是欧盟认可的GLP实验室。而我国的化学品GLP管理规范才刚刚起步,与OECD组织的GLP规范还有一定差距。我国的化学品监督管理部门还需进行大量的工作,以推进化学品GLP的实施,并力求加入GLP MAD协议,推进国际安全性资料的互认。  相似文献   
938.
以山嵛酸、DCC为原料,DMAP为催化剂首次合成新型化合物N,N’-二环己基-N-山嵛酸酸酰脲,并对合成路线进行优化,核磁共振谱确定结构;检测其体外抗BEL-7404细胞的活性。结果表明,通过对合成路线的优化可以快速,简便的合成N,N’-二环己基-N-山嵛酸酰脲,产率可以达到85%以上;其在400μg/mL以上浓度以上对人肝癌7404细胞有较为明显的杀伤。该物质有望成为新型的抗肿瘤先导化合物。  相似文献   
939.
添加剂强化粉煤燃烧固硫剂的研究   总被引:1,自引:0,他引:1  
耿曼  陈定盛  梁旭林 《广东化工》2010,37(8):246-247,249
文章选取CaCO3、Ca(OH)2质量配比=3∶2作为主固硫剂,用2%钙基(质量配比)的Na2CO3对其改性,利用蛭石作为固硫添加剂。在Ca/S=2.25的情况下通过固硫实验考察了主固硫剂以及添加剂的加入对固硫率的影响。实验表明:煤粉掺入该固硫剂在950℃下燃烧半小时,固硫率可以达到85%,该固硫剂主要由天然矿物所组成,具有来源广、成本低廉等优势,因而具有极高的应用价值和市场推广潜力。  相似文献   
940.
通过测量管内低温气体、管壁温度分布及冰层图相,分析了波纹内翅片管管内传热热阻、管壁温度和冰层增长的变化特性。结果表明:内翅片管管内传热阻仅为光管的6.65%,由管壁至管内低温气体的热流量大大增加,因此,管外冰层增长速度在距入口250 mm和500 mm处分别约为光管的4.2倍和1.7倍。冰层热阻占整个耦合传热总热阻的比例更大,以至于管外冰层热阻的增加引起管壁和管内气体温度的降低。由于内翅片管管内低温气体沿轴向温升更大,使其冰层厚度沿轴向斜率远大于光管。  相似文献   
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