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本文合成了七种典型的吡唑酮型成品红成色剂、根据Brand提出彩色显影方程γ=Alogτ+B,测定了这些成色剂的照相活性A。作者论证了在相同显影条件下,A值与吡唑酮型成品红成色剂彩色显影的偶合速度成正比。另外,作者运用SCF-PPP-MO方法计算了吡唑酮型成品红成色剂模型分子中偶合位置上的电子密度、超离域度及定域能等反应参数,发现lnA与电子密度具有较好的线性关系,其关系式为: lnA=15.97Qr,-18.03 (n=6,r=0.95) 从而得出:彩色显影偶合反应是静电作用控制的。 相似文献
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烟草三维荧光特征和品质评吸的关系 总被引:2,自引:0,他引:2
研究不同品种烟草石油醚冷萃取物的三维荧光光谱,包括烟草所共在的荧光性质和各自的荧光特性,寻找它们与烟草香味,颈头等吃味之间的关系,选择合适的量值指标,为烟草品质的 观感官评估提供了一个实用的对照方法。 相似文献
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叶大年 《中国科学B辑(英文版)》1989,(3)
The optical anisotropy index is a new conception which has been proposed by the author of this paper on the basis of the Gladstone refractivity (i.e. specific energy by Larsen). The conception is very useful for studying the structural-optical mineralogy. The polarizability ellipsoid of atom groups in minerals may be obtained from the optical anisotropy index; conversely, when the crystal structure, orientation, and the polarizability ellipsoid of atom groups are known, the optical anisotropy index of the minerals may be calculated, and then three principal refractive indices, and the optical axis angles may be calculated, too. The calculated values of optical properties are in very good agreement with the experimental values. This calculation method is much simpler thanBragg's for the carbonates, and the precision of calculated values is much higher than that of Bragg's. The principle of calculation method is suitable for all the minerals containing some strong anisotropic atom groups, besides carbonat 相似文献
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本工作采用溴加成法、酚解法、FTIR法及臭氧裂解法分别测定了五种不饱和蒸气压下聚合的PVC样品(u-PVC)和五种商品PVC样品(s-PVC)的总双键、总不稳定氯、孤立双键和内部双键的含量.通过研究结构缺陷和PVC的平均分子量及脱HCl速率的相互关系,揭示了不饱和总双键值,总不稳定氯和孤立双键含量彼此的相关性是建立在它们分别与1/M_n的相关性基础之上,从而得出了这三种定量值测得的主要都是端基烯丙基氯结构.根据三者对脱HCl速率的良好线性相关性,首次提出了端基烯丙基氯结构在HCl催化作用下异构化成内部烯丙基氯从而成为脱HCl速率主要原因的机理. 相似文献
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改性分子筛的表面酸性与苯烷基化反应活性的关系研究 总被引:3,自引:0,他引:3
用Ca2+、Sr2+、Ba2+、La3+和NH+4交换改性的Y型沸石具有合适的表面酸性,可代替HF作为固体酸催化剂用于苯与长直链烯烃的烷基化反应。用正丁胺TPD研究表明:在改性分子筛表面存在两种强度的酸位,其对应的脱附温度分别为300和450℃,这两种强度的酸位峰面积在反应前后有不同程度的下降,强酸位下降得较多。吡啶吸附FT-IR的结果表明:催化剂表面L酸与B酸同时存在,苯与长直链烯烃烷基化反应的活性与中等强度的酸位有很好的对应关系,而与酸的类型关系不明显。 相似文献
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同族元素及化合物的性能与周期序数的关系 总被引:1,自引:0,他引:1
本文用周期序数的倒数 1 / n代表同族原子大体结构效应的因素 ,用公式 :P=a b/ n将同族元素及化合物的二十多种性能 (P)对 1 / n进行线性回归 ,得到良好结果。 相似文献
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高分子固体电解质—聚醚—硫氰酸盐络合物的电导与结构关系 总被引:1,自引:0,他引:1
关于高分子量聚环氧乙烷(PEO)与碱金属硫氰酸盐络合物电导方面的工作先后报道的有Wright、Tanzella、Lee及王超英等.本工作研究PEO中EO链节与NaCNS或KCNS的摩尔比及添加γ-丁内酯对导电率的影响以及其结晶结构与导电率的关系,得到某些尚未见报道的结果。 相似文献
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聚合物材料缺口冲击强度与断面粗糙度参数Rs的关系 总被引:6,自引:0,他引:6
金属材料断面粗糙度的测定描述及其与材料性能间的关系已有很多报道,研究结果表明,随断面粗糙度表征参量(分形维数DF,表面粗糙度参数RS)增大,金属材料的一些宏观力学性能(断裂韧性KIC,冲击韧性aK,疲劳门槛值ΔKth等)增高,但这些研究都较少涉及材料的断裂机制[1~3].聚合物材料断面粗糙度的定量研究较少,有关聚合物材料断面粗糙度与材料韧性间关系的定量结论也不一致[4,5],体现出聚合物材料断面粗糙度定量分析的复杂性.本文通过对不同试验温度下几种聚合物材料冲击断面粗糙度的定量测定,研究了聚合物材… 相似文献
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在阴离子型和非离子型表面活性剂组成的反胶束体系中研究了直径为11~14nm的AgCl微粒子与菁染料之间的作用,讨论了AgCl纳米粒子对菁染料的吸附及荧光猝灭现象. 相似文献
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本文研究了光生电子和还原剂提供的电子在卤化银晶体中的行为。光灰化和还原剂灰化生成的灰雾中心的位置不同。光灰化时灰雾中心优先在卤化银颗粒内部形成,表明光生电子可以直接进入卤化银晶体的导带。还原灰化时内部灰雾中心只有在灰化剂量足够多时才形成,而且滞后于表面灰雾中心的形成,表明还原剂提供的电子虽然可以进入卤化银的导带,但它们进入导带的方式与光生电子不同。 相似文献
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The adsorption amount of poly(styrene sulfonate)and poly(dimethyldiallyl ammonium chloride)(PSS/PDDA) self-assembled multilayer membranes in designed dipping solvents were measured by UV-Vis-spectroscopy and quartz crystal microbalance(QCM).Intrinsic viscosities of PSS and PDDA in corresponding dipping solvents were determined by an Ubbelohde viscometer.It is found that the adsorption amount of PSS/PDDA self-assembled multilayer membranes built up in different dipping solutions,added salt concentration,p... 相似文献
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《Journal of Coordination Chemistry》2012,65(1):173-198
Abstract The 1:1 molar ratio reaction of p-phenylenediamine with isonitrosoacetylacetone in chloroform led to the formation of the half unit ligand (HL); (1). Two types of the trans octahedral (L)2Ni 2H2O complex were characterized; the green molecular complex (2) and the associated supramolecular dark brown complex (3). Molecular association in (3) took place via inter-molecular hydrogen bonding between the amino group of a molecule and the oxygen sites of an adjacent molecule. The 1:1 molar ratio reactions of (2) with the metal acetates M(OAc)2 (M = divalent nickel, copper or cobalt) produced the self-assembly structure (4) whereby the metal acetate is coordinated to the amino groups of the nickel(II) complex. Reaction of the dinuclear (4) with another metal acetate (1:1 molar ratio) gave the trinuclear terminated structure (5). Similar reactions of (3) with nickel acetate (1:1 or 1:2) led to formation of complexes with metallosupramolecular structures. An antiferromagnetic interaction between the peripheral and central paramagnetic units was observed from those complexes with copper(II) at the peripheral location. In all these cases the metal ions are bridged via the aromatic Schiff-base moiety. The suggested structures of the mono-, di- and trinuclear coordination compounds are in accordance with the analytical, spectral and magnetic moment data. 相似文献
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开放式微波消解与干灰化法消解测量食品中铅的方法比较 总被引:1,自引:0,他引:1
对开放式微波消解法与干灰化法消解测量食品中铅的方法进行了比较,试验表明,前者操作简易,试验周期短,在测量精度和加标回收率方面两种方法无显著性差别。 相似文献
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Chemical reactions between poly (vinyl pyridine)s and 1, 4-butanediol diglycidyl ether and other epoxy compounds were studied by Fourier transform infrared spectroscopy and other techniques. The epoxy group was found to react with the pyridine side group of poly (4-vinyl pyridine), forming crosslinked networks which contain cyclic amide structures. The reaction was also observed in the interracial region of poly(vinyl pyridine) and γ-glycidoxy propyl trimethoxysilane hydrolyzate (γ-GPS) coatings on PET fiber substrates. Poly(2-vinyi pyridine) does not show the same reaction. 相似文献