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41.
Hybrid precursors were assembled with cerium coordination polymers, polyethyl glycohol (PEG), SrCO3 and other functional components using a modified in-situ chemical polymeric gel technology. The hybrid precursors were calcinated to achieve the Sr2CeO4 phosphors, whose particle sizes were in the range of micrometer by XRD and SEM. The photoluminescence spectra indicate that the phosphors present a strong blue emission.  相似文献   
42.
Abstract The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plantsobtained whose protein content was higher than 18.5%, the highest one was 21.44%. There were 3plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We cansee that the whole DNA of soybean transformed into wheat via ion beam implantation can inducethe increase in wheat protein content dramatically. The result also shows that the transformationefficiency of different gene types of wheat receptor varies greatly that the implanting time has acertain effect on the efficiency of transformation.  相似文献   
43.
Masanori Yamada  Hirofumi Aono 《Polymer》2008,49(21):4658-4665
Double-stranded DNA is one of functional polymers, but the large amounts of DNA sources, such as salmon milt and shellfish gonads, have been discarded as industrial wastes. Therefore, conversion of this discarded DNA to be a useful material would be beneficial to utilize the unique property of DNA. These materials including DNA have been prepared by mixing with the organic polymers, such as alginic acid, collagen, and chitosan. However, since these materials have consisted from entirely organic components, these do not have the mechanical strength for a material. So, we prepared the organic-inorganic hybrid materials by mixing DNA with silane coupling reagents bis(trimethoxysilylpropyl)amine or bis[(3-trimethoxysilyl)propyl]ethylenediamine. These hybrid materials with the flexibility were water-insoluble and resistant to hydrolysis by nuclease. In addition, the mechanical strength of this hybrid material was approximately twice as high as that of DNA without mixing with silane coupling reagents. Furthermore, the double-stranded DNA in the hybrid materials has been maintained in a B-form structure in aqueous solution. Thus, we demonstrated the utilization of DNA as a functional material. As a result, this material could selectively accumulate harmful DNA-intercalating compounds with the planar structure, such as dibenzo-p-dioxin, dibenzofuran, and ethidium bromide. Organic-inorganic hybrid material including double-stranded DNA has potential to serve as a useful biomaterial for medical, engineering, and environmental applications.  相似文献   
44.
This paper describes a method of analyzing the maximum buckling strength of hybrid-fiber multilayer-sandwich cylindrical shells under external lateral pressure with respect to fiber orientations and weighting factors. Formulae for optimizing these parameters are presented and conditions for the application of these formulae are discussed. A discriminant is derived for assessing whether the hybrid sandwich cylindrical shells for given different unidirectional composites should reach the extreme value of critical pressure.  相似文献   
45.
东津水电站引水隧洞进口段工程地质条件恶劣,施工干扰大,渡汛工期紧。采用喷锚支护洞脸边坡,洞口明挖3m浇筑钢筋混凝土明拱和L形护坡墙;洞身段采用新奥法施工,先打通上导洞;进口40m分段开挖,分段衬砌;进水塔压板混凝土模板采用门字框架钢支撑;排除了施工干扰,防止了洞口滑塌,进口段塌方的恶性事故发生,保证了引水隧洞工程的顺利施工。  相似文献   
46.
The phase behavior of a hybrid polymer network (HPN) composed of poly[(propylene glycol maleate)-co-(propylene glycol phthalate)] crosslinked with styrene and polyester–urethane crosslinked with methylene-bis-ortho-chloroaniline was examined. The correlation between phase separation and impact strength of the HPNs is discussed. The composition of HPNs has an effect on their properties.  相似文献   
47.
针对拼接结构的高分辨率彩色等离子体大屏幕系统的应用,指出了刷新型电路模式的不足之处,提出了一种混合型模式的驱动电路。从彩色模块ACPDP的结构特性出发,详细讨论了该电路的工作原理,驱动波形以及放电过程。  相似文献   
48.
带中置锅炉的氨合成塔和带后置式锅炉的氨合成塔,在结构和节能方面有许多异同之处.本文经过计算,定量地对这两种塔进行比较.  相似文献   
49.
分析 6 0 0 0m3 /h空分设备原氮水预冷系统存在的问题及原因 ,将水循环由原制氧站大循环改为氮水预冷系统内部的自循环 ,只增加水换热器和蓄水器 ,效果明显。  相似文献   
50.
A micromechanical model called MESOTEX is presented for prediction of the elastic behaviour of composites reinforced with non-hybrid weave (plain weave, satin weave and twill weave) and hybrid weave (hybrid plain weave and hybrid twill weave) fabrics. By using the classical thin laminate theory applied to each woven structure, this analytical model takes into account the strand undulations in the two directions and also integrates the geometrical and mechanical parameters of each constituent (resin, fill and warp strands). A representative volume is chosen for each woven composite and the fibre architecture is described by several functions. To determine the effectiveness of this analysis, the elastic properties predicted for each woven composite are compared with experimental results and results extracted from the literature. This correlation shows excellent agreement between measured and predicted values, with a very low calculation cost (CPU time of less than 0·01 s).  相似文献   
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