共查询到20条相似文献,搜索用时 31 毫秒
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塑料和聚烯烃材料爆露在空气中被氧化降解使之失去使用价值。该问题可通过添加稳定剂解决。但是当材料与金接触时,某些金属离子或金属可加速氧化反应,这会明显降低制品的使用寿命。这时应加入金属离子钝化剂,以降低聚合物的降解。本文综述了该类产品的合成与应用,还介绍了一些工业化的品种。 相似文献
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Sukharev S. V. Zabolotskii A. V. Kotrovskii P. V. Turchin M. Yu. 《Refractories and Industrial Ceramics》2020,61(1):1-4
Refractories and Industrial Ceramics - We study the problem of evaluation of the influence of design of the metal receiver of a large-capacity tundish of slab continuous-casting machine on the... 相似文献
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Qi Zhiyuan Chen Luning Zhang Shuchen Su Ji Somorjai Gabor A. 《Topics in Catalysis》2020,63(7-8):628-634
Topics in Catalysis - Research evolved using nanoparticles synthesized and characterized under reaction conditions opened the door to study all three fields of catalysis: heterogeneous, homogenous,... 相似文献
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Sukharev S. V. Zabolotskii A. V. Kotrovskii P. V. Turchin M. Yu. 《Refractories and Industrial Ceramics》2020,60(6):539-542
Refractories and Industrial Ceramics - We study the problem of evaluation of the influence of design of the metal receiver of a large-capacity tundish of slab continuous-casting machine on the... 相似文献
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Synthesis and properties of a resacetophenone-formaldehyde resin are described. The number average molecular weight of the resin determined by vapour pressure osmometry and nonaqueous conductometric titration is 2500 and 2200 g/mol, respectively. Cu(II), Ni(II) and Co(II) chelates of the resin were prepared. The elemental analysis of chelates indicated a metal to ligand ratio 1:2. From the diffuse reflectance spectra of the chelates it could be concluded that Ni(II) and Co(II) chelates have a tetrahedral structure while Cu(II) chelate has a square planar structure. Infrared spectral studies showed that the metals are co-ordinated through the oxygen of the carbonyl and phenolic groups. The presence of methylene bridges was also indicated from IR spectral studies. The thermal properties of the resin and its metal chelates are discussed. 相似文献
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Ginger V. Shultz David R. Tyler 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(4):423-435
This review describes the synthesis of functional dimeric metal carbonyl complexes and their subsequent polymerization to
afford polymers containing metal–metal bonds in the main chain. Such polymers are photodegradable because the metal–metal
bonds are cleavable by visible light. The functionalization of the dimeric complexes and their polymerization is challenging
due to the reactivity of the M–M bond, and therefore many standard synthesis and polymerization methods cannot be used. Various
polymerization methods are discussed including ring-opening metathesis polymerization, acyclic diene metathesis polymerization,
ring-opening polymerization, traditional step polymerization, and copper-catalyzed step polymerization using click chemistry. 相似文献
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Ernst‐Christian Koch 《Propellants, Explosives, Pyrotechnics》2004,29(1):9-18
The potential of strained fluorocarbons, which can act as oxidizers in metal‐based pyrolant systems, is investigated. The oxidizing performance of fluorocarbons is evaluated by the enthalpy of combustion ΔcH(298K) and the fractional electron transfer ΔN. ΔcH(298K) can be related to hybridisation, molar C/F ratio and strain of the parent carbon skeleton of the fluorocarbon. Considered fluorocarbons are tetrafluorotetrahedrane (CF)4 ( 3 ), tetrakis(trifluoromethyl)tetrahedrane C4(CF3)4 ( 4 ), hexafluoro[3]prismane (CF)6 ( 5 ), hexakis(trifluoromethyl)[3]prismane C6(CF3)6 ( 6 ), octafluorocubane (CF)8 ( 7 ), octakis(trifluoromethyl)cubane C8(CF3)8 ( 8 ), eicosafluorododecahedrane (CF)20 ( 9 ), eicosakis(trifluoromethyl)dodecahedrane C20(CF3)20 ( 10 ), C60F48 ( 11 ) and perfluorofullerane (CF)60 ( 12 ). Powerful oxidisers in terms of exothermicity are those possessing both tertiary C F‐units and strained carbon skeletons. Nevertheless the reactivity, which is estimated on basis of ΔN, the fraction of electrons transferred according to Pearson, has been found to be high with the corresponding perfluoromethyl derivatives and maximum with the fluorofulleranes. For part IV see Ref. 17. 相似文献
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A.A. Kornyshev 《Electrochimica acta》1989,34(12):1829-1847
The role of metal electrons in the response of the metal—electrolyte interface to charging is discussed in view of recent density-functional and phenomenological theories. The emphasis is given to the predicted capacity—charge plots and electromodulated optical signals. 相似文献
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High-Performance Directional Metallopolyamides. II. Optical Spectroscopic Studies of Metal Chelation
Odessa N. Petzold Issifu I. Harruna 《Journal of Inorganic and Organometallic Polymers》2000,10(4):249-264
The chelating interaction between metal ions and 4,4-disubstituted-2,2-bipyridyl-containing high-performance polymeric ligands prepared from 2,2-bipyridyl-4,4-dicarboxylic acid and a series of primary aromatic diamines was investigated by optical spectroscopy. Optical spectroscopic studies of the chelation of ruthenium ions by the 2,2-bipyridyl-containing polyamides revealed the formation of distinct ruthenium(II) complexes [RuII(poly)L4] (
max=530 nm), [RuII(poly)2L2] (
max=584 nm), and [RuII(poly)3]2+ (
max=476 nm), while iron(II) ions formed only one complex (
max=569 nm). The diverse functional features of the polymer repeat unit directly influences the chelation of metal ions. 相似文献
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采用非抑制型离子色谱法、阳离子交换柱、电导检测器,以柠檬酸-苹果酸-乙二胺为淋洗液,同时测定Ag 、Cu2 、Cd2 、Zn2 、Pb2 五种离子.研究了淋洗液配比及淋洗液pH对分离效果的影响,选择了最佳分离条件,得出五种离子的工作曲线方程,相关系数为0.989~0.999,检出限为0.02~0.1 μg/mL,RSD为1.64%~4.03%,样品加标回收率为98%~104%.本方法用于烟叶样品的分析,具有简便、快速、检出限低,灵敏度高,准确度高、选择性好的特点. 相似文献
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T. E. Whyte Jr. 《Catalysis Reviews》2013,55(1):117-134
The variety of supported metal catalysts utilized in the operations of the petroleum and chemical industries emphasizes the importance of metal-catalyzed reactions. As a result, many scientific investigators have attempted to characterize and follow closely the changes in the crystallite size and shape of supported metal particles in commercial and simulated environments. From these efforts a massive production of experimental facts has emerged. 相似文献