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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.
Baoqing Zhang Julia Shuk‐Ping Wong Richard Ching‐Man Yam Robert Kwok‐Yiu Li 《Polymer Engineering and Science》2010,50(5):900-910
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.
Ik Sang Shin Sung Mo Son Dae Ho Lim Yong Kang Heon Jung Ho Tae Lee 《Korean Journal of Chemical Engineering》2010,27(3):1015-1020
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
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