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81.
有机化合物如有机金属化合物、有机酸、有机胺和有机硫化物等在加氢精制催化剂的研制中具有重要作用,在制备催化剂的中用这些有机化合物处理可提高催化剂的活性和稳定性或降低成本,本文对这些有机化合物在这方面应用的技术加以综述。 相似文献
82.
Sol—Gel法制备有机—无机复合光致变色膜 总被引:1,自引:0,他引:1
本文讨论了用sol-gel法在有机改性SiO2基体中于室温下俘陷有机染料如螺吡喃或螺恶嗪,制备出具有光致变色功能的有机-无机复合膜。该膜层在可见光区的最大吸收峰位于620mn处。 相似文献
83.
Bubble wake visualization by using photochromic dye 总被引:1,自引:0,他引:1
Wake structure of a single “clean bubble”, rising in rectilinear, zigzagging or spiraling path, is experimentally investigated. A single nitrogen gas bubble was produced in a silicone oil pool and the wake structure development in the rear of the rising bubble was visualized by using photochromic dye. The flexibility of this visualization method enabled us to distinguish wake from drift easily. Both bubble motion and wake structure were recorded by using stereo high-speed video camera simultaneously. We present the first experimental support for the existence of the standing eddy at the rear of the clean bubble, as predicted by a previous numerical study by Ryskin and Leal [1984. Journal of Fluid Mechanics 148, 19-35], Dandy and Leal [1986. Physics of Fluids 29(5), 1360-1366] and Blanco and Magnaudet [1995. Physics of Fluids 7(6), 1265-1274]. We study motion of a pair of vortex filaments, which is called double-threaded type wake, in the case of bubble rising in an axi-asymmetric path. Visualization results of multiple formations of horse-shoe type vortices in one period of zigzag motion of rising bubble with shape oscillations, which has not been observed in previous studies are also presented. 相似文献
84.
Dario Natali Mario Caironi Marco Sampietro Andrew P. Meacham Steven J. Vickers Michael D. Ward 《Optical Materials》2006,28(12):1362-1365
We report on the electrochromic behavior of a dinuclear ruthenium complex, which provides high environmental stability together with an intense absorption maximum at 1237 nm in solution in its +3 oxidation state. To verify its optoelectronic properties, we used this complex as the photoactive material in a planar photodetector prototype for near-infrared light pulses, succeeding in the detection of a train of light pulses at a wavelength of 1280 nm. 相似文献
85.
Till Böcking Michael James Christopher L. Brown Kevin D. Barrow 《Thin solid films》2006,515(4):1857-1863
Poly(amidoamine) dendrimers were attached to activated undecanoic acid monolayers, covalently linked to smooth silicon surfaces via Si-C bonds. The resulting ultra-thin dendrimer films were characterized by X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XR) and atomic force microscopy (AFM). XPS results suggested amide bond formation between the dendrimer and the surface carboxylic acid groups. XR yielded thicknesses of 10 Å for the alkyl region of the undecanoic acid monolayer and 12 Å for the dendrimer layer, considerably smaller than the diameter of these spherical macromolecules in solution. This was consistent with AFM images showing collapsed dendrimers on the surface. It was concluded that the deformation arose from a large number of amine groups on the surface of each dendrimer reacting efficiently with the activated surface, whereby the dendrimers can deform to fill voids while spreading over the activated surface to form a homogeneous macromolecular layer. 相似文献
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88.
由1,4,5,8—四羟基蒽醌和对甲苯胺为主要原料,在一个反应器内同时完成了缩合和磺化两步单元反应,合成酸性蒽醌绿染料,并对其反应条件对产物收率的影响进行了研究,确定了最佳合成工艺条件(反应时间16 h、反应温度120℃、原料的配比1:2.2)。 相似文献
89.
弱酸性、中性染料对氨纶的染色及其在氨纶上的吸附等温线 总被引:6,自引:0,他引:6
任信 《苏州大学学报(工科版)》2005,25(3):63-68
通过测试中性染料和不同结构的弱酸性染料在氨纶上的上染率,分析染料结构与上染率的关系,并且研究了1:2金属络合染料在氨纶上的吸附规律,并运用Langmuir和Nernst二元吸附模型对吸附等温线进行了分析。 相似文献
90.
A mathematical model was developed to estimate the efficacy of coagulation–flocculation treatment for removing neutral hydrophobic organic chemicals from raw drinking water. The model assumed that the only significant removal mechanism was the destabilization and settling of organic matter containing sorbed anthropogenic organic compounds. The model was validated with standard jar tests using compounds with a range of hydrophobicities (log?Kow = 1.89?to?5.48), including contaminant candidate list chemicals, pesticides, pharmaceuticals, and endocrine disrupting chemicals. Final concentrations of test compounds after coagulation and flocculation were in good agreement with model estimations for synthetic waters composed of Aldrich (Milwaukee, WI) humic acid solutions. The final compound concentrations in coagulated natural waters from two drinking water reservoirs were about 80% lower than those estimated with the model. Overestimations of treated water concentrations by the model were attributed to an increase in sorption by natural organic matter when coiled in aluminum hydroxide flocs, compared to sorption to dispersed natural organic matter in untreated water. 相似文献