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41.
The central composition experimental design of multiva-riate Response Surface Method was used to formulate mathematical models aiming to predict (1) the optimum dyeing conditions of simulated waste Tikuanyin tea for wool fabric and (2) the optimum extraction conditions of a natural mordant originated from common waste eggshell. The pre - mordanting eggshell was applied to wool fabric before dyeing with simulated waste Tikuanyin tea under the optimum dyeing conditions. After mordanting the wool fabric with extracted natural eggshell solution, the prominent effect of increment in dye uptake and improvement of the properties of light fastness, washing fastness and rubbing fastness were evaluated.  相似文献   
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E Tsui  D Yeung 《Experientia》1979,35(10):1293-1294
gamma-Glutamylcysteine synthetase is present in barely detectable amounts in foetal kidney. Its activity starts to increase in postnatal life. In contrast, oxoproline is already found in significant quantities in the foetal tissue. Both enzymes show marked elevation in activities during the weaning period.  相似文献   
44.
1,2,3,4 - butanetetracarboxylic acid (BTCA) offers an alternative to the conventional N-methlol compounds as a crosslinking agent for cellulose textiles. Cellulase treatment is an effective method to improve the handle of the cotton fabric. Thus it is of particular interest to treat cotton fabric using cellulose and BTCA simultaneously. In this study, BTCA was applied to the cellulase pre-treated cotton fabric, and softener was also used. The results show that the treated fabric does not only have good wrinkle-free property but also good handle.  相似文献   
45.
The aim of this study explored the importance of colour application on clothing and investigated whether there is a preference of colour on clothing among children under hospital environment. A modified colour associated test based on the Luster Color Test was used to carry out the survey. Fifty child patients aged four to sixteen were asked to look at two specially designed colour cards and to name their preferences and associations on each of the colour.  相似文献   
46.
The cellular machinery promoting phagocytosis of corpses of apoptotic cells is well conserved from worms to mammals. An important component is the Caenorhabditis elegans engulfment receptor CED-1 (ref. 1) and its Drosophila orthologue, Draper. The CED-1/Draper signalling pathway is also essential for the phagocytosis of other types of 'modified self' including necrotic cells, developmentally pruned axons and dendrites, and axons undergoing Wallerian degeneration. Here we show that Drosophila Shark, a non-receptor tyrosine kinase similar to mammalian Syk and Zap-70, binds Draper through an immunoreceptor tyrosine-based activation motif (ITAM) in the Draper intracellular domain. We show that Shark activity is essential for Draper-mediated signalling events in vivo, including the recruitment of glial membranes to severed axons and the phagocytosis of axonal debris and neuronal cell corpses by glia. We also show that the Src family kinase (SFK) Src42A can markedly increase Draper phosphorylation and is essential for glial phagocytic activity. We propose that ligand-dependent Draper receptor activation initiates the Src42A-dependent tyrosine phosphorylation of Draper, the association of Shark and the activation of the Draper pathway. These Draper-Src42A-Shark interactions are strikingly similar to mammalian immunoreceptor-SFK-Syk signalling events in mammalian myeloid and lymphoid cells. Thus, Draper seems to be an ancient immunoreceptor with an extracellular domain tuned to modified self, and an intracellular domain promoting phagocytosis through an ITAM-domain-SFK-Syk-mediated signalling cascade.  相似文献   
47.
传统能源稀缺已直接影响世界各国经济和人类生活,并已成为人类未来能否在地球上继续生存亟待解决的问题。由于地球能源中除核能、地热能与地球形成初期的状况有关外,一切已知的化学能量都是直接或间接来自太阳,因此人类所面临的能源困境,其实是太阳能量得失失衡的问题,其根源在于人类消耗能量的速度,已明显高于太阳能的直接或间接收集效率以及转化利用率。太阳能是目前人类主要的持久能源,要充分利用太阳能就必须进一步揭示阳光更深层的本质和运动规律,进而研制出可以高效收集和转化利用太阳能的新装置设备。本文简要讨论关于阳光的若干问题,提出光群场假设和光微粒、子光群、光源常数、子光群分布密度、持久能源等新概念,并简述借助太阳能飞行器来研究太阳能的创新方法,以及中国太阳能飞行器研制及其科学意义。  相似文献   
48.
Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.  相似文献   
49.
变体飞艇创新技术及其科学意义   总被引:2,自引:0,他引:2  
由于现代社会对航空技术的要求不断提高,以及不可再生能源日渐稀缺、环保条件等因素变化所带来的需求,飞艇重新成为人们高度关注的飞行器.本文简要阐述了变体飞艇这种新概念飞行器的科学原理与技术方法,并通过技术比对来分析变体飞艇相对于传统飞艇的创新点,及其在航空航天等领域应用的重大科学意义.  相似文献   
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