何以为镓？

Gallium is the 31st element in the periodic table of elements. In this paper, the discovery, nature and application of gallium are introduced in the form of storytelling, aiming at giving readers a full understanding of "what is gallium?"     

X‐Ray Investigations of the intrinsic Carbon‐Incorporation during the MOVPE Growth of AlxGa1‐xAs

We have investigated the intrinsic C‐incorporation during the metalorganic vapour‐phase epitaxy of GaAs, (Al,Ga)As, and AlAs. The carbon from the methyl radicals of trimethylgallium and trimethylaluminium has been used as intrinsic carbon source and the necessary growth conditions (low growth temperatures and low V/III‐ratios) have been determined. Under these conditions we observed a reduction of the Al‐incorporation in (Al,Ga)As resulting from a change of surface kinetics at low temperatures. We have used the tensile tetragonal lattice distortion due to the C‐incorporation for determination of the carbon concentration. This has been done by investigating the symmetric (004) reflection peaks of GaAs and the strained epitaxial layer by high resolution x‐ray diffraction. The resulting carbon concentrations showed a good agreement with the hole concentrations determined by Hall measurements and spectroscopic ellipsometry.     

Atomic structures of GaAs(100)-(2 × 4) reconstructions

Atomic structures of the As-rich GaAs(100)-(2 × 4) reconstructions based on converged first-principles total-energy calculations are reported. All geometries are characterized by similar structural elements such as As dimers with a length of about 2.5 Å, dimer vacancies, and a nearly planar configuration of the three-fold coordinated second-layer Ga atoms leading to a steepening of the dimer block. For an As coverage of θ = 3/4 we find the two-dimer β2 phase to be energetically preferred over the three-dimer β phase. A structure with partial replacement of As by Ga in the uppermost layer corresponding to an As coverage of is found to be slightly less favourable than the phase of GaAs(100). Geometry parameters are given for all structures and compared with the available experimental results.     

磺化酞菁镓、钒、铝、锌在水、醇、胶束中的聚合行为的研究

采用分光光度法研究了四磺化酞菁镓,钒,铝和二磺化酞菁锌在水,醇－水,胶束体系中的聚合行为,测定了配合物的二聚常数。结果表明,ＡｌＴＳＰｃ形成二聚体是一个慢反应,而ＧａＴＳＰｃ,ＺｎＢＳＰｃ和ＶＯＴＳＰｃ的二聚体形成是快速过程。     

Evaluation of departure from stoichiometry of gallium arsenide crystals

A method is described for determining arsenic in gallium arsenide. In order to avoid the conventional pre-reduction process, arsenic is directly titrated iodimetrically as As(V) in acidic solution. The determination is made with an automatic titrator and potentiometric detection of the equivalent point. Pure arsenic is used as a reference substance. Deviations from the stoichiometric composition of the order of 10^?3-10^?4% with a standard deviation of about 0.06% can be determined. The limits of chemical analysis for controlling the stoichiometry of the semiconductor are discussed.     

Two layered gallophosphates assembled about the chiral metal complexes: Co(en)3·Ga3P4O16·5H2O and trans−Co(dien)2·Ga3P4O16·3H2O

Two new layered gallophosphates Co(en)₃·Ga₃P₄O₁₆·5H₂O (1) and trans-Co(dien)₂·Ga₃P₄O₁₆·3H₂O (2) have been hydrothermally synthesized using the racemic mixture of chiral metal complex Co(en)₃Cl₃ and Co(dien)₂Cl₃ as the structure-directing agent, respectively. Their structures are determined by single-crystal X-ray diffraction analysis and further characterized by X-ray power diffraction, ICP, elemental, and TG analyses. The structures of 1 and 2 consist of vertex-linking GaO₄ and PO₃(=O) tetrahedral units forming macroanionic [Ga₃P₄O₁₆]³⁻ sheets with a 4.6-net. The 4.6-net is characteristic of chiral [3.3.3] propellane-like structural motifs. The sheets of 1 stack in an ABAB sequence, with a pair of enantiomers of chiral Co(en)₃³⁺ cations residing in the interlayer region. The sheets of 2 array in a helical fashion with an ABCDEF stacking sequence, with only one enantiomer of chiral Co(dien)₂³⁺ cations residing in the interlayer region. Structural elucidation of 1 and 2 reveals that there exist stereo-specific correspondence between the metal complex template and the structure of the inorganic host. Crystal data: 1, Co(en)₃·Ga₃P₄O₁₆·5H₂O, orthorhombic, Pnna (No. 52), a=8.6618(2) Å, b=21.6071(5) Å, c=13.7426(4) Å, Z=4, R₁=0.0337 (I>2σ(I)), wR₂=0.0985 (all data); 2, Co(dien)₂·Ga₃P₄O₁₆·3H₂O, hexagonal, P6₅22 (No. 179), a=8.5152(7) Å, b=8.5152(7) Å, c=63.278(8) Å, R₁=0.1183 (I>2σ(I)), wR₂=0.2864 (all data) and Z=6.     

Synthesis and characterization of two novel organocation containing group 13 metal ethylenediphosphonates

Two novel group 13 metal diphosphonates: (H₃NC₃H₆NH₃)₂[Al₂F₆(O₃PC₂H₄PO₃)]·H₂O (1) (monoclinic, C2/c, a=16.9697(7) Å, b=8.0273(4) Å, c=16.3797(8) Å, β=117.762(2)°, Z=4, R₁=4.66%, wR₂=11.82%), and (H₃NC₃H₆NH₃)[Ga₂F₄(O₃PC₂H₄PO₃)] (2) (triclinic, P-1, a=5.398(7) Å, b=8.122(6) Å, c=15.839(18) Å, α=78.89(4)°, β=89.60(7)°, γ=79.35(6)°, Z=2, R₁=2.90%, wR₂=3.17%) have been synthesized by solvothermal methods in the presence of the propyldiammonium cations and their structures determined using single and micro-crystal X-ray diffraction data, respectively. The structures of 1 and 2 are closely related and contain dimers of edge-sharing trivalent metal centered octahedra that are linked together by the ethylenediphosphonate groups to form chains and aperture-containing layers, respectively. The propyldiammonium cations surround the aluminum diphosphonate chains in 1 and separate the gallium diphosphonate layers in 2. Both compounds 1 and 2 are examples of metal phosphonate materials containing only one type of octahedral-tetrahedral secondary building unit (SBU-4).     

石墨炉原子吸收光谱法测定高温合金中镓

研究了普通石墨管、平台石墨管和涂钼普通石墨管对镓的测定性能.得出涂钼普通石墨管对镓的测定灵敏度和重现性均好于其他石墨管.从而建立了一种更为满意的石墨炉原子吸收测定高温合金中镓的新方法.     

CL-P204萃淋树脂吸萃镓的性能和机理

本文采用静态法研究了CL-P204萃淋巴脂在硫酸介质中吸萃镓的性能。结果表明，在pH2.8时，镓在树脂上的分配系数最大，其吸附反应的热效应为43.2KJ/mol，树脂对镓的饱和吸附容量为42.4mg/g；吸萃过程为离子交换过程。