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971.
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976.
The induced codeposition mechanism of Mo, P and Ni from the solution of ammoniac citrate was studied by means of steady-state polarization, AC impedance and X-ray Photoelectron Spectroscopy (XPS). The result of electrochemical measurements proved that [NiCit(NHs)2]- is the electro-active species of nickel, though nickel ions exist mainly as [NiCit(NH3)3]? in ammoniac citrate. XPS experiments proved the existence of tetravalent molybdenum corresponding to MoO2 on the surface of mme deposits. The intermediate product, MoO2, WM probably reduced to Mo in the alloy deposit by atomic hydrogen adsorbed on the induced metal nickel. The reduction of H2PO?2 occurs through two distinctive steps with PH3 an an intermediate, which subsequently reacts with atomic hydrogen to form P in the alloy deposit. The electrodeposition mechanism was proposed in this paper. 相似文献
977.
以Philips-VanVechten理论和晶体光学性质为基础,计算了LaX(X=N,P,As,Sb)晶体的离子半径(单位:nm):(La:N)为(0.1414,0.1236),(La:P)为(0.1518,0.1489),(La:As)为(0.1536,0.1526),(La:Sb)为(0.1586,0.1651).用LMTO-ASA方法对LaX系列晶体的能带结构进行了计算.所得到的能隙是:LaN为2.30eV,LaP为2.05eV,LaAs为1.66eV,LaSb为1.34eV.与实验结果相符.这也证明了作者得到的半径的合理性. 相似文献
978.
Xifra R Ribas X Llobet A Poater A Duran M Solà M Stack TD Benet-Buchholz J Donnadieu B Mahía J Parella T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(17):5146-5156
A family of highly stable organometallic Cu(III) complexes with monoanionic triazamacrocyclic ligands (L(i)) with general formula [CuL(i)]+ have been prepared and isolated, and their structural, spectroscopic, and redox properties thoroughly investigated. The HL(i) ligands have been designed in order to understand and quantify the electronic effects exerted by electron donor and electron-withdrawing groups on either the aromatic ring or the central secondary amine or on both. In the solid state the Cu(III) complexes were mainly characterized by single-crystal X-ray diffraction analysis, whereas in solution their structural characterization was mainly based on 1H NMR spectroscopy given the diamagnetic nature of the d(8) square-planar Cu(III) complexes. Cyclic voltammetry together with 1H NMR and UV/Vis spectroscopy have allowed us to quantify the electronic effects exerted by the ligands on the Cu(III) metal center. A theoretical analysis of this family of Cu(III) complexes has also been undertaken by DFT calculations to gain a deeper insight into the electronic structure of these complexes, which has in turn allowed a greater understanding of the nature of the UV/Vis transitions as well as the molecular orbitals involved. 相似文献
979.
Hermitean vector spaces E of infinite dimensions are considered. Let G be a subgroup of the orthogonal group of E acting on a set M. The Lattice Method is a technique for classifying the orbits in M under G. We discuss the method in abstract terms and we illustrate it by means of three classification results showing that it is decisive to do a considerable amount of explicit calculations with vector subspace lattices. 相似文献
980.
Kenzo Sato 《International Journal of Infrared and Millimeter Waves》1987,8(1):69-102
From analysis of anisotropical lattice bands properties of 50 reflection spectra both of the CO stretching and bending bands measured from some pearl (Ca++CO
3
––
or Ca++HCO
3
––
layer) we discussed following subjects.i) Quantized properties present both in reflectivity and in energy. ii) classifications of the Optical Activity. iii) Polar distributions of the CO3 oscillators in Ca++CO
3
––
surface mono-layer. iv) Force constants of these oscillators. v) Step variation of the dipolemoment and their influences to the degree of Optical Activity. vi) Two types of hysteresis loops of the values of YN (M2Jbend ()/M1Jstret. ()) derived from the oscillators which are at innert-state, at weak active-state and at active-state. 相似文献