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971.
972.
The preparation and characterization of a new cyclometalated iridium complex with 2-(1-naphthalene) pyridine ligand were reported. An electrophosphorescent device was fabricated by using this new iridium complex as guest and poly-(cyano-paraphenylene) as host. Red electrophosphorescence was observed with an emission peak at approximately 600 nm. An external quantum efficiency of 1.3% was achieved in this electrophosphorescent polymer light-emitting devices. 相似文献
973.
974.
975.
介绍了几种方法 ,用以消除或减小计量方式和谐波对电能量的计量方面带来的负面影响 ,使电能计量更加准确、公正和合理 相似文献
976.
XiaoyanLi JieZhang XianlinChen JianguoCao HaixiaLi 《北京科技大学学报(英文版)》2004,11(3):251-255
A study on roll gap profile (strip profile) control was accomplished in a 1700 mm single-stand temper mill. Some critical problems such as the deviation of work roll contour caused by grinding and wear, the effectiveness of work roll bending were discussed. Using a finite element model, the effects of roll contours (ground and wear) on strip profile were investigated. The roll bending effect on strip thickness was also analyzed. It is pointed out that there are some special features of flatness control in the temper mill: during temper rolling, roll deformation is slight due to small rolling load, and the loaded roll gap profile mainly depends on work roll contour, while the backup roll has a little effect on gap crown; the effect of bending force on gauge can not be ignored due to the coupling between flatness control and gauge control. A new roll contour arrangement adaptable to the mill was presented and has been put into practical production. The application of the new set of rolls showed some good results: larger crown control range of work roll bender, higher rolling stability, better strip profile and flatness quality. 相似文献
977.
γ-alkoxy-propylamines, C12H25O(CH2)3NH2, C14H29O(CH2)3NH2, C16H33O(CH2)3NH2, C18H37O(CH2)3NH2 were synthesized from aliphatic alcohol and acrylonitrile. The flotation tests of kaolinite, pyrophyllite and illite were
conducted. The flotation mechanisms were explained in view of the structures of reagents and aluminium silicate minerals,
zeta potential and Fourier transform infrared spectrum measurements. The results show that the synthesized r-alkoxy-propylamines
are more effective than dodecyl amine for flotation of kaolinite, pyrophyllite and illite. For flotation kaolinite and illite,
the collecting ability is in the order of C18H37O(CH2)3NH2>C16H33O(CH2)3NH2> C14H29O(CH2)3NH2>C12H25O(CH2)3NH2, but the r-alkoxy-propylamines types of collectors have almost the same collecting ability on pyrophyllite, which demonstrating
that γ-alkoxy-propylamines are new selective collectors for reverse floatation to remove aluminium silicate minerals from
bauxite.
Foundation item: Project (G1999064901) supported by the National Key Fundamental Research and Development Program of China; project (59925412)
supported by the National Science Foundation for Distinguished Scholar 相似文献
978.
串联式混合动力城市公交车车载数据采集系统开发 总被引:4,自引:1,他引:4
根据串联式混合动力系统的特点 ,研制开发了串联式混合动力城市公交车车载数据采集系统。该系统能够对串联式混合动力城市公交车准确记录所需各种信息 ,且能根据采集的数据对串联式混合动力城市公交车进行性能评价 相似文献
979.
Kexing Song Jiandong Xing Qiming Dong Ping Liu Baohong Tian Xianjie Cao 《Materials Science and Engineering: A》2004,380(1-2):117-122
The mechanisms responsible for the nucleation, growth and coarsening of Al2O3 particles in dilute Cu–Al alloys during internal oxidation have been investigated, and the alumina morphologies produced have been studied by electron microscopy using two-stage preshadowed carbon replica method. The alumina particle size has been observed to increase with increasing temperature of oxidation, with increasing time of oxidation, and with decreasing oxygen resource coefficient over the experimental range. These results indicate that the alumina particle size is determined by a competition between the rate of nucleation as the internal oxidation front passes and the subsequent growth and coarsening rates of the particles. 相似文献
980.
Duetoincreasingcropyieldsandimprovingcropquality ,REammoniumhydrogencarbonatecomplexfertilizerwereappliedwidelyinsoils ,whichacceler atetheaccumulationofREinsoilsafteragriculturalapplication[1,2 ] .Previousstudieshavereportedaccu mulationofREsinsoilissignificantafter 3monthsofagriculturalapplication[3] ,andREhardlymigratedownward[4 ] .Itiscertaintythatagriculturalapplica tionofREcanresultREaccumulationinsoilandmayhaveaneffectonsoilmicrobialactivities .Soilmicro bialbiomassisamarkerofthemi… 相似文献