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51.
52.
新型发光、无机和有机纳米型染料主要用于聚对苯二甲酸乙二醇酯(PET)纤维的制备。PET纤维是制作用于预警和安保系统的纤维织物的原材料。具有发光性质的纳米染料的制备方法主要有两种:一种为自下而上,沉淀法合成;另一种为自上而下,通过反应型研磨得到。下述的纳米染料是硫化锌(ZnS),同时还掺杂有铜或锰、铝酸锶,还可掺杂铕和镝。此外,还对有机染料和颜料(醛连氮和二萘嵌苯)进行研究,还将其包裹于硅纳米粒子中并进行相关研究。制得的纳米粒子混入高分子熔体中,通过熔融挤出得到成品丝。该过程中所使用的纳米颜料可混入母粒中,也可制成液状使用。最后进行成品丝变形工艺研究,并加工成纺织面料。纳米发光颜料的加入实现了低染料剂量下的高发光性。与已投入使用的传统体系相比,采用纳米发光颜料的体系具有更好的光、热和湿牢度。 相似文献
53.
孟加拉侯赛化学有限公司 《硫酸工业》2001,(3):49
孟加拉侯赛化学有限公司(HCCL)150kt/a粒状普钙(GSSP)工程是由南化集团设计院和中国化工建设总公司共同承包的化肥交钥匙工程.该工程包括60kt/a硫磺制酸及150kt/a粒状普钙,硫酸工艺采用快速熔硫、自然沉降和"3+1”两转两吸工艺,普钙采用湿磨磷矿、磷矿浆混化、皮带化沉、造粒和干燥工艺.中方主要负责工程的设计,主要设备、材料的采购,设备安装和开车指导;外方负责工程的土建设计,施工及设备、材料的安装工作.工程造价约406万美元(不含外方负责工作费用).目前,已完成工程的详细设计和主要设备的采购,预计工程将于2002年8月完工投产,工程建成后,可极大缓解该国的化肥紧缺状况.
(南化集团设计院邱世庭) 相似文献
54.
杂质分离器是一种有效的降低纤维杂质的工具。搭配几种灵敏感应器模块的系统能有效地检测和去除几类杂质。这样的系统也可成功地用于轧棉工序。 相似文献
55.
Defects in CVDZnS 总被引:1,自引:0,他引:1
FU Liganga b Lü Fanxiua WANG Xuewub WEI Naiguangb a School of Materials Science Engineering University of Science Technology Beijing Beijing China b Beijing Guojing Infrared Optical Technology Co.Ltd. General Research Institute for Nonferrous Metals Beijing China 《稀有金属(英文版)》2011,30(4):387-391
Defects seriously influence the optical properties and mechanical properties of CVDZnS.The deposition technique was introduced and experiment methods such as SEM,TEM and OM were adopted to study the defects:hexagonal phase,abnormally large grains,micro-cracks,micro-pores and impurities.The microstructures of these defects were observed,and the formation mechanisms of these defects were analyzed.Hexagonal ZnS as an impurity causes anisotropy in different directions with different refraction indexes and increases the scattering of CVDZnS.Increasing the deposition temperature can inhibit the formation of the hexagonal phase.The main reason for the growth of abnormally large grains in CVDZnS is high deposition rate.The lower deposition temperature increases growth stress in CVDZnS,which consequently results in the bowing of CVDZnS plates,and introduces microscopic defects such as grain blending and micro-cracks in the crystal.Micro-pores and impurities are induced by high reactant concentration in the local deposition chamber,which can be avoided by improving the gas flowing so as to make the concentration more uniform. 相似文献
56.
57.
Moncia García Fernández 《世界建筑导报》2010,25(1)
项目地点:西班牙塞埃欣项目类型:景观设计开工日期:2005年12月该项目获2005年豪瑞可持续建筑大奖赛欧洲地区提名奖 相似文献
58.
An automatic purge and trap apparatus, coupled to a GC-MS was used to study the seasonal variability of the volatile fraction of raw milk Manchego cheese. Both season and dairy significantly affected abundance of most volatile compounds. Most aldehydes, methyl ketones, n-alcohols, and secondary alcohols reached significantly higher concentrations in spring cheeses. Branched chain alcohols showed significantly higher concentrations in autumn and winter cheeses, while significantly higher amounts of diketones were found in summer cheeses. Most ethyl esters reached higher concentrations in spring and winter cheeses and lower in autumn cheeses. Lower concentrations of alpha-pinene were found in spring cheeses, and higher amounts of limonene were observed in winter cheeses. Heptane and octane were significantly more abundant in summer cheeses. No significant seasonal differences were found either for quality or intensity scores. 相似文献
59.
Commercial refrigerated or frozen flatfish fillets are sometimes mislabeled, and identification of these mislabeled products is necessary to prevent fraudulent substitution. Identification of nine commercial flatfish species (order Pleuronectiformes), Hippoglossus hippoglossus (halibut), Lepidorhombus boscii (four-spotted scaldfish), Lepidorhombus whiffiagonis (megrin), Platichthys flesus (flounder), Pleuronectes platessa (European plaice), Reinhardtius hippoglossoides (Greenland halibut), Scophthalmus maximus (turbot), Scophthalmus rhombus (brill), and Solea vulgaris (=Solea solea) (sole), was carried out on the basis of the amplification of a 486-bp segment of the mitochondrial genome (tRNA(Glu)/cytochrome b) by using the polymerase chain reaction (PCR) and universal primers. Sequences of PCR-amplified DNA from the flatfish species were used to select eight restriction enzymes (REs). The PCR products were cut with each RE, resulting in species-specific restriction fragment length polymorphism. Seven species groups could be identified by application of the single RE DdeI and six species groups by using HaeIII, HinfI, MaeI, or MboI. Different combinations of only a couple of these REs could unambiguously identify the nine flatfish species. Genetic polymorphisms of the target sequence were examined by comparison with previously published DNA sequences, and the results of this comparison confirmed the usefulness of this technique in distinguishing and genetically characterizing refrigerated or frozen pieces of these nine flatfish species. 相似文献
60.
Simão AG Guimarães LG de Mendonça JP 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(10):2053-2063
A theoretical and numerical investigation is devised for resonant light scattering of an off-axis normally incident Gaussian beam by two parallel nonabsorbing cylinders based on the related beam theory developed in J. Opt. Soc. Am. A 14, 640 (1997). By varying the half-beam width, we show that the multireflection process between the two scatterers can be minimized. Moreover, the study is an attempt to understand the underlying physics present in the process of resonance excitation by evanescent wave coupling. 相似文献