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1.
分析了影响磺酸色泽的主要因素,并阐述了解决这一问题的对策,为提高磺化产品的质量奠定了基础,使企业在市场竞争中获得竞争优势.  相似文献   
2.
服装面料表面反射光与面料的光泽及视觉风格有着密切的关系 .从服装面料表面反射光设计的一般原则和主要影响因素两个方面对这一问题进行了分析 ,并以缎纹织物为例对面料表面反射光的设计进行了探讨 .研究可知 ,影响服装面料表面反射光的主要因素包括纤维性状 ,纱线结构和织物结构 .另外 ,面料的后整理方法对面料表面反射光也有较大影响 .在众多影响因素中 ,以纤维的表面、纵向形态及截面性状影响最大 .服装面料表面反射光的设计应综合考虑各种因素 .  相似文献   
3.
Reactions of N-(2,4-dinitrophenyl)-4-arylpyridinium chlorides (aryl (Ar) = phenyl and 4-pyridyl) with piperazines caused the ring opening of the pyridinium ring and yielded polymers that consisted of 5-piperazinium-3-aryl-penta-2,4-dienylideneammonium chloride units [N(CH(R)CH2)2N+(Cl)CHCHC(Ar)CHCH, RH, Me, and phenyl]. However, the same reactions occurring in the presence of piperidine yielded oligomers that consisted of 5-piperazinium-3-aryl-penta-2,4-dienylideneammonium chloride units having piperidine and/or piperazine rings at both ends. 1H NMR spectra suggested that π-electrons of the penta-2,4-dienylideneammonium group of the polymers and the oligomers were delocalized. UV-vis measurements revealed that the π-conjugation system expanded along the polymer and oligomer chains due to the orbital interaction between electrons on the two nitrogen atoms of the piperazinium ring. Conversion of the piperazinium ring from the boat form to the chair form caused decrease in the π-conjugation length. The rate constants of the conversion of the oligomers depended on their chain lengths. The surface of pellets that were molded from the polymers and oligomers exhibited metallic luster. These polymers and oligomers underwent electrochemical oxidation in solution.  相似文献   
4.
超喂率是影响空气变形纱(以下简称空变纱)及其织物结构性能的一个重要参数。本文就超喂率对空变纱的形态结构、光泽、强伸度、摩擦等性能以及对空变纱织物性能的影响进行了较全面的实验研究,给出了实测数据,并通过分析而引出了重要结论。  相似文献   
5.
J. Kunnen 《Rheologica Acta》1988,27(6):575-579
The Fulcher-Tammann-Hesse-Vogel equation, ln = A + B/(T – T 0 ), is shown to be equivalent to the general viscosity-composition relationship, ln r =k f /(1 – f ), for binary mixtures. The Cailletet-Mathias law of the Rectilinear Diameter is rearranged to represent a density mixture formula for two components. Temperature-independent viscosities and densities can then be calculated for dense, solid cluster fractions, dispersed in a low-density, low-viscosity non-clustered continuous phase. The cluster fraction decreases with temperature. The value ofT 0 is shown to be related to the liquid- or solid-like behavior of the clusters. For liquids with a vapor pressure < 1 mm Hg at the melting point, the calculated cluster volume fraction suggests close packing of clusters, ranging in shape from monodisperse spheres to polydisperse non-spherical particles. Examples are given for molecular liquids, molten metals, and molten salts. The size of the clusters is estimated from the heat of evaporation.  相似文献   
6.
含硫磷桥基的两核铁羰基簇合物的合成和晶体结构   总被引:1,自引:0,他引:1  
Fe3(CO)12与杂环二硫代次膦酸盐SP(C6H4OR)(S)N(C6H5)NC(Me)(R=Me,Et)反应,得到两个新的含硫磷桥基的双核铁羰基簇合物Fe2(CO)6[μ-η2-SC(Me)NN(C6H5)P(C6H4OMe)](Ⅰ)和Fe2(CO)6[μ-η2-SC(Me)NN(C6H5)P(C6H4OEt)](Ⅱ),以及簇合物Fe3(CO)9(μ3-S)2(已知).对它们进行了元素分析,IR,1HNMR和MS等谱学表征,并用X-ray衍射技术测定了(Ⅰ)的晶体结构.该晶体属单斜晶系,P2(1)/n空间群,晶胞参数a=11.192(2)A,b=14.272(3)A,c=16.281(3)A,β=108.22(3).,V=2470.2(8)A3,Z=4.两核簇合物中含有两个桥基Fe-S-Fe和Fe-P-Fe,而且-C(7)-N(2)-N(1)-链连结在S、P原子间,形成了两个六员螯环Fe(1)SCNNP和Fe(2)PNNCS,增强了簇合物的稳定性.  相似文献   
7.
通过大理石中主要造岩矿物的岩组分析认为,岩石内部结构中矿物排列方向的定向性对大理石石材光泽度以及抗压强度均会产生一定的影响。而且岩石中矿物成份与结构构造对其起着一定的控制作用。通过对几种不同类型大理石中方解石矿物晶体进行的显微构造分析,确定出晶体的优选方位,并经过实验,获得一定的肯定性结论,初步论证了利用大理石中矿物优选方位来选择石料切片方位以获取具有高光泽度和较大抗压强度优质大理石石材的可行性。  相似文献   
8.
Reactions of N‐(2,4‐dinitrophenyl)pyridinium chloride with 2,5‐dimethyl‐1,4‐phenylenediamine in 1:2, 1:1.5, 1:1, and 2:1 molar ratios caused the ring opening of the pyridinium ring and thereby yielded polymers ( P1 – P4 ) consisting of 5‐(2,5‐dimethyl‐1,4‐phenylene)penta‐2,4‐dienylideneammonium chloride (unit A) and N‐2,5‐dimethyl‐1,4‐phenylene diaza[12]annulenium dichloride (unit B). The 1H NMR spectra suggested that the composition ratios of unit A to unit B in P1 – P4 were 0.98:0.02, 0.94:0.06, 0.81:0.19, and 0.79:0.21, respectively. P1 – P4 showed an absorption maximum (λmax) at a longer wavelength than the monomers because of the expansion of the π‐conjugation system. Films of P3 and P4 showed λmax at a considerably longer wavelength than those in solution, and this was attributable to the ordered structures of the polymers in the solid state. Powder X‐ray diffraction analysis supported the ordered structures of P3 and P4 . Pellets molded from P3 and P4 exhibited a metallic luster, whereas those from P1 and P2 did not show such a luster. Cyclic voltammetry measurements indicated that P1 – P4 were electrochemically active in films. The thermal stability of the polymers depended on the composition ratios of unit A to unit B. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1507–1514, 2007  相似文献   
9.
运用光的反射、折射、迭加性质并结合晶体光学原理,用数学语言定性地探讨了石材抛光面光泽度形成原因。  相似文献   
10.
根据光反射物理学、色彩学、神经生理学和感觉判断心理学的研究成果,建立了织物光泽感产生的理论模型,并对织物光泽与光泽感作了确切的描述.在物理学领域的光泽感的光学空间域提出了反光度X1,亮度差异率X2,漫射光X3等3个综合参量指标;在生理学领域光泽感的刺激空间域提出了生理反射量Y1,生理光泽量Y2,生理漫射量Y3等3个参量指标;在心理学领域的光泽感的知觉空间域提出了光亮度Z1,光泽度Z2,背景光Z3等3个指标,并建立了其间相互转换的隶属度函数式.  相似文献   
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