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31.
Gallium(III) catecholates with bipyridine ligand [(3,5-Cat)Ga(bipy)2]I and (3,6-Cat)GaI(bipy) (Cat is di-tert-butylcatecholate) were synthesized and characterized by single-crystal X-ray diffraction. The appearance of near-infrared ligand-to-ligand charge transfer for pentacoordinate complex was observed.  相似文献   
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33.
《Analytical letters》2012,45(4):231-234
Abstract

A method is presented for the rapid solvent extraction of gallium (III) with o, o, s-triethyldithiophosphate. Quantitative extraction results from 4–9 M hydrochloric acid, using 100% extractant. The extract-able species is H[GaCl4]·2(C2H5 O2)2 P(S)SC2H5.  相似文献   
34.
Organogallium or-indium subhalides are easily available by the halogenation of the corresponding tetrahedral clusters E 4 [C(SiMe 3 ) 3 ] 4 . Three types of compounds are formed that retain the tetrahedral arrangement of In atoms or give chains with two or three Ga or In atoms connected by E─E bonds. These subhalides are suitable starting compounds for the synthesis of secondary products containing the elements in low oxidation states. Carboxylato derivatives or transition metal complexes were obtained on such a route. A persistent radical anion was formed on electron transfer to Ga 9 (CMe 3 ) 9 .  相似文献   
35.
Abstract

Density functional theory (DFT) calculations at the B3LYP/6–31G* level were performed to investigate covalent functionalization of imidazole on pristine (in gas and H2O phases) and Ga-doped BPNT models in terms of energetic, geometric, and electronic properties. The results show that imidazole, as a functional group, prefers to be adsorbed via its nitrogen atom on the pristine, GaB, and GaP nanotube models. The adsorption energy of imidazole on the (6,0) zigzag BPNT in gas and solvent phases is ?0.76 and ?1.11 eV, respectively, and about 0.38 and 0.43 electron are transferred from the imidazole to nanotube in the phases. The presence of a polar solvent increases the electron donor of imidazole molecule. The results show that Ga doping can significantly enhance the adsorption energy of imidazole on the nanotube models to about 95%.

Moreover, the imidazole adsorption on the pristine and Ga-doped BPNT models has not significant changes in the energy gap of the nanotube models and it is slightly changed after covalent functionalization process. This study may provide new insight to the development of functionalized boron phosphide nanotubes for generation of the new hybrid compounds especially in drug delivery systems for virtual applications.  相似文献   
36.
Abstract

A series of iron, cobalt and nickel metal phosphides of chemical formula FexP, Co2P and Ni2P with high specific surface areas of 331.1, 294.2 and 228.0 m2 g?1, respectively, was firstly synthesized by phenol-formaldehyde resin route. It was found that the as-prepared Co2P and Ni2P samples synthesized using phenol-formaldehyde resin as a carbon source showed much higher BET surface areas than those prepared using other carbon sources reported before, including cinnamic strong alkali anion exchange resin, p-phenylenediamine and hexamethylenetetramine. This phenol-formaldehyde resin route was proved to be as universal as traditional H2 reduction method.  相似文献   
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38.
By taking advantage of UV‐Raman spectroscopy and high‐resolution TEM (HRTEM), combined with the focused ion beam (FIB) technique, the transformation from GaOOH into α‐Ga2O3 and then into β‐Ga2O3 was followed. We found that the stepwise transformations took place from the surface region before developing into the bulk of single particles without particle agglomeration and growth. During the transformation from GaOOH into α‐Ga2O3, the elimination of water vapor through the dehydroxylation of GaOOH resulted in the formation of micropores in the single particles, whilst maintaining their particle size. For the phase transformation from α‐Ga2O3 into β‐Ga2O3, the nucleation of β‐Ga2O3 was found to occur at the surface defects and this process could be retarded by occupying these defects with a small amount of La2O3. By finely controlling the process of the phase transformation, the β‐Ga2O3 domains gradually developed from the surface into the bulk of the single particles without particle agglomeration. Therefore, the surface structure of the α‐Ga2O3 single particles can be easily tuned and a particle with an α@β core–shell phase structure has been obtained.  相似文献   
39.
采用热重-质谱联用技术研究了次磷酸盐在氮气中的热分解过程,探讨了次磷酸盐热分解法制备磷化镍的反应机理:次磷酸镍中的Ni2+能够"催化"H2PO2-低温发生歧化反应生成PH3,继而还原Ni2+得到Ni2P。制备了不同负载量的Ni2P/SiO2催化剂,用X射线衍射(XRD)、低温N2吸附-脱附、高分辨透射电镜(HRTEM)等分析技术对催化剂结构进行表征。结果表明,Ni2P活性组分在SiO2载体上具有良好的分散性,颗粒粒径为5~8 nm。以喹啉为加氢脱氮模型化合物,在高压微型固定床反应器上对催化剂活性进行评价,在反应温度为360℃、氢气压力为2.0 MPa、液时空速为2.0 h-1、氢油体积比为500:1时,Ni2P(20%)/SiO2催化剂的加氢脱氮率为41.5%。  相似文献   
40.
Simple cyclic renewable silver amalgam film electrode (Hg(Ag)FE), applied for the determination of gallium(III) using differential pulse anodic stripping voltammetry (DP ASV), is presented. The effects of various factors such as: preconcentration potential and time, pulse height, step potential and supporting electrolyte composition are optimised. The calibration graph is linear from 5?nM (0.35?µg?L?1) to 80?nM (5.6?µg?L?1) for a preconcentration time of 60?s, with correlation coefficient of 0.995. For a Hg(Ag)FE with a surface area of 9.9?mm2 the detection limit for a preconcentration time of 120?s is as low as 0.1?µg?L?1. The repeatability of the method at a concentration level of the analyte as low as 3.5?µg?L?1, expressed as RSD is 3.2% (n?=?5). The proposed method was successfully applied by studying the synthetic samples and simultaneously recovery of Ga(III) from spiked aluminium samples.  相似文献   
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