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81.
The solid-liquid equilibrium diagrams of binary mixtures involving magnesium nitrate hexahydrate with cobalt nitrate hexahydrate, nickel nitrate hexahydrate (partly), manganese nitrate tetrahydrate, and iron(III) nitrate nonahydrate and of magnesium chloride hexahydrate with cobalt and nickel chlorides hexahydrates and manganese chloride tetrahydrate, and the of two manganese salts were determined. Those diagrams that showed a simple eutectic were fitted by the Ott equation and where the required BET parameters were available, the magnesium salt rich parts of the liquidus were modeled by means of this method. 相似文献
82.
研究了金属离子对吸附在银胶表面的中位-四(4-N甲氧羰甲基吡啶)卟啉表面增强拉曼光谱的影响。结果表明,中位-四(4-N甲氧羰甲基吡啶)卟啉可发生金属离子取代反应。金属离子嵌入卟啉大环,吸附在银胶表面的中位-四(4-N甲氧羰甲基吡啶)卟啉转变为金属配合物。给出了各种金属配合物主要拉曼峰的经验式归属。金属离子的半径,d电子对卟啉环的排斥作用,金属卟啉骨架模式频率随孔穴大小,大环的平面性和π-π相互作用而相应变化的特性,都可用来解释不同金属离子配合物的结构灵敏特征峰为何存在着差异。 相似文献
83.
Summary A numer of bonded stationary phases were investigated for the separation of Cd2+, Cu2+, Fe3+, Mn2+, Ni2+, Pb2+, and Zn2+ by thin-layer chromatography. The effect of structure, surface loading, type of silica gel and mobile phase concentration was considered. 相似文献
84.
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86.
Lü Renqing ZHANG Hongyu QIU Guangmin LIU Chenguang College of Chemistry Chemical Engineering China University of Petroleum 《Chinese Journal of Reactive Polymers》2005,(Z1)
1. INTRODUCTION Chitin, the most abundant natural amino polysaccharide and estimated to be produced annually almost as much as cellulose, is well known to consist of 2-acetamido-2-deoxy-β-D- glucose through α, β(1→4) linkage. Chitin is the major source of surface pollution in coastalareas. Chitosan is the N-deacetylated derivative of chitin and their structures are shown in Fig. 1. Fig. 1 Structures of Chitin and Chitosan Because of the excellent properties such as biocompatibility… 相似文献
87.
四羧基金属酞菁负载纤维素纤维的制备及其消臭性能研究 总被引:2,自引:0,他引:2
合成了四羧基铁酞菁(Fe-CPc)和四羧基钴酞菁(Co-CPc),并对其进行了元素分析和红外光谱表征.在酸性条件下,将四羧基金属酞菁负载到改性纤维素纤维上,制备得到消臭纤维.实验结果表明,在室温条件下,四羧基铁酞菁消臭纤维(FePcF)、四羧基钴酞菁消臭纤维(CoPcF)和混合金属酞菁消臭纤维(CoFePcF)3种功能性纤维都能有效去除甲硫醇、硫化氢、氨气和三甲胺,甲硫醇和硫化氢按催化氧化机理除去,而氨气和三甲胺按酸碱中和机理除去;3种消臭纤维对甲硫醇和硫化氢的消臭效果为CoFePcF>CoPcF>FePcF. 相似文献
88.
A rigid terpyridine ligand containing chiral alkyl chains has been synthesized, characterized and subsequently complexed with ruthenium(II) ions. The product was characterized by MALDI-TOF-MS, UV-vis and NMR. Circular dichroism showed the appearance of extended helical columnar aggregates. 相似文献
89.
We report the synthesis of Fmoc protected single amino acid chelates (SAAC) and their metal complexes. The modified amino acids are suitable for solid-phase peptide synthesis. The use of 4-hydroxymethylbenzoic acid AM (HMBA-AM) resin allows the nucleophilic cleavage of the peptide-metal complexes from the resin without decomplexation. 相似文献
90.
《Arabian Journal of Chemistry》2022,15(12):104347
The high-pressure structures and properties of MH2 (M = Nb, Ta) are explored through an ab initio evolutionary algorithm for crystal structure prediction and first-principles calculations. It is found that NbH2 undergoes a phase transition from a cubic Fmm structure with regular NbH8 cubes to an orthorhombic Pnma structure with fascinating distorted NbH9 tetrakaidecahedrons at 48.8 GPa, while the phase transition pressure of TaH2 from a hexagonal P63mc phase with slightly distorted TaH7 decahedron to an orthorhombic Pnma phase with attractive distorted TaH9 tetrakaidecahedrons is about 90.0 GPa. Besides, the calculated electronic band structure and density of states demonstrate that all of these structures are metallic. The Poisson’s ratio, electron localization function, and Bader charge analysis suggest that these phases possess dominant ionic bonding character with the effective charges transferring from the metal atom to H. From our electron–phonon calculations, the calculated superconducting critical temperature Tc of the Pnma-NbH2 is 6.903 K at 50 GPa. Finally, via the quasi-harmonic approximation method, the phase diagrams at pressure up to 300 GPa and temperature up to 1000 K of MH2 (M = Nb, Ta) are established, where the transition pressure of Fmm-NbH2 → Pnma-NbH2 and P63mc-TaH2 → Pnma-TaH2 were found to decrease with increasing temperature. 相似文献