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31.
O. S. Filipenko S. M. Aldoshin G. V. Shilov N. I. Makarova V. A. Kharlanov M. I. Knyazhanskii 《Russian Chemical Bulletin》1995,44(2):287-292
The molecular structures of the initial compounds and the products of photocyclization involving amino and azomethine groups in perchlorates ofN-amino (1) andN-azomethine (2) derivatives of 2,4,6-triphenylpyridinium cations were studied. Cations1 and2 have an essentially non-coplanar arrangement of the -Ph rings, and the product of photocyclization of2, cation3, is characterized by a flattened structure. It was found that the orientation of the lone electron pair of the N atom with respect to one of the planes of the -Ph rings in molecule1 is more favorable for monocyclization involving the amino group. The structure of molecule2 allows two routes of the photoreaction,viz., O N proton transfer and monocyclization with an -Ph ring. However, the structural features of molecule2 are more favorable for photocyclization.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 296–301, February, 1995. 相似文献
32.
在很高的温度和适宜的生长条件下,分别采用熔盐籽晶法和高温引上法生长了高质量的YAP、NAB、KTP、LN、BBO、SBN等多元氧化物单晶,它们具有优良的物理化学性能,严格的化学比,固定的组成与结构以及较好的化学均匀性和电子束轰击下的稳定性。广泛地用于激光和非线性光学领域。我们选用这些晶体为原材料研制电子探针定量分析的标准样品。经过测量和标定,这些单晶标样符合中华人民共和国国家标准GB 4930-85(电子探针显微分析标准样品通用技术条件)的规定。含有稀土元素的标样如NAB和YAP能发出绿色荧光,是电子显微术中理想的阴极发光材料。 相似文献
33.
Crystal Structure of Hexamine Cyclotriphosphazene, P3N3(NH2)6 In the presence of KNH2 hexamine cyclotriphosphazene semi ammoniate (molar ratio 12:1) in NH3 gives crystals of solvent free P3N3(NH2)6 within 5 d at 130°C and p(NH3) = 110 bar. The structure was solved by X-rax methods: P3N3(NH2)6: P21/c, Z = 4, a = 10.889(6) Å, b = 5.9531(6) Å, c = 13.744(8) Å, β = 97.83(3)°, Z(Fo) = 1 721 with (Fo)2 ≥ 3σ(Fo)2, Z(var.) = 157, R/Rw = 0,036/0,041 The structure contains columns of molecules P3N3(NH2)6 all in the same orientation. The six-membered rings within one molecule have boat conformation. The columns are stacked together in a way that one is surrounded by four others shifted by half a lattice constant in direction [010]. Strong hydrogen bridge-bonds N? H…?N connect molecules within the columns and between them. 相似文献
34.
Joon Myong Song 《Analytica chimica acta》2003,487(1):75-82
In this work, a combination of complementary metal-oxide semiconductor (CMOS) microchip system with capillary array electrophoresis (CAE) is demonstrated as a system for optimizing conditions for enzymatic reaction. Dimethylacridinone (DDAO)-phosphate substrate and alkaline phosphatase conjugate were selected for the enzymatic reaction, which was applicable to the enzyme-linked immunosorbent assay (ELISA) technique. Laser-induced fluorometry with a miniature semiconductor laser was used to detect the enzymatic products. The speed of the enzymatic reaction between the DDAO-phosphate and the alkaline phosphatase conjugate was investigated as a function of reaction time. The microchip-CAE detection system could determine the pH condition and the concentration of enzyme that are suitable for rapid and low-cost analysis. This result shows the feasibility of using the microchip-CAE system for application to miniaturized screening systems. 相似文献
35.
Preparation and crystal structure of the La2Ni12P5 and isotypic ternary lanthanoid—Nickel phosphides
Yu. B. Kuz'ma V. S. Babizhet'sky S. I. Chykhrij S. V. Oryshchyn V. K. Pecharsky 《无机化学与普通化学杂志》1993,619(3):587-592
The new ternary phosphide La2Ni12P5 has been prepared by direct arc melting of the components as pure metals and red phosphorus. The crystal structure has been determined using X-ray single crystal diffraction data. The compound exhibits a new type of crystal structure, P21/m with lattice parameters a = 10.911(3), b = 3.696(2), c = 13.174(4) Å, β = 108.02(2)°, V = 505,2(6) Å3, Z = 2. Atomic parameters least squares refinement of 116 independent variables (anisotropic approximation for thermal vibrations) employed 1 284 independent Io(hkl); RF = 0.0278 and RW = 0.0287. The crystal structure is characterized by trigonal prismatic arrangement of phosphorus atoms stacking variant of infinite (with phosphorus centered) columns built by metal trigonal prisms ‖ [010]. Two or three such columns are connected through common edges (lanthanum atoms). The compounds RE2Ni12P5 (where RE = Ce, Pr, Nd and Eu) display the same with La2Ni12P5 crystal structure. Lattice parameters of these compounds have been refined using powder diffraction data. 相似文献
36.
A.A. FilaretovM.G. Zhizhin L.N. KomissarovaV.P. Danilov V.V. ChernyshevB.I. Lazoryak 《Journal of solid state chemistry》2002,166(2):362-368
A new ammonium indium phosphate (NH4)In(OH)PO4 was prepared by hydrothermal reaction in the In2O3-NH4H2PO4-NH3/OH system (T=200°C, autogenous pressure, 7 days). The formula (NH4)In(OH)PO4 was determined on the basis of chemical and thermal analysis (TG/DSC), X-ray powder diffraction and IR-spectroscopy. (NH4)In(OH)PO4 crystallizes in the tetragonal system with space group P43212 (No. 96); a=9.4232(1) Å, c=11.1766(1) Å, V=992.45(2) Å3; Z=8. The crystal structure was refined by the Rietveld method (Rw=6.35%, Rp=5.10%). The second-harmonic generation study confirmed that structure of (NH4)In(OH)PO4 does not have a center of symmetry. The cis-InO4(OH)2 octahedra form helical chains, parallel to the c-axis. The In-O-In bonds are nearly equidistant. The chains are interconnected by phosphate tetrahedra and create tunnels containing the NH4+ ions along the c-axis. (NH4)In(OH)PO4 is isostructural with RbIn(OH)PO4. 相似文献
37.
P. A. Stabnikov N. V. Pervukhina I. A. Baidina L. A. Sheludyakova S. V. Borisov 《Journal of Structural Chemistry》2007,48(1):186-192
The crystal structure of iron tris-acetylacetonate is re-determined. Crystal data at 293 K are: a = 15.4524(5) Å, b = 13.5876(4) Å, c = 16.5729(7) Å, Z = 8; at 150 K: a = 15.2541(4) Å, b = 13.4451(3) Å, c = 16.4256(5) Å, Z = 8. The structure is molecular and comprises isolated molecules. The coordination polyhderon of iron is an almost regular octahedron, Fe-O bond lengths are 1.977–2.003 Å (293 K) and 1.982–2.006 Å (150 K). In the crystalline state, the molecules are arranged in layers, and iron atoms are located on a plane yielding an almost regular trigonal net with the Fe...Fe separations of 7.558–8.103 Å (293 K) and 7.472–8.017 Å (150 K). The adjacent layer is positioned exactly over the first one with a Fe...Fe distance of 8.303 Å (293 K) and 8.236 Å (150 K). 相似文献
38.
Dubravka Matković-Čalogović Zora Popović Branka Korpar-Čolig 《Journal of chemical crystallography》1995,25(8):453-458
[Hg(terpy)2](CF3SO3)2·0.5(CH3)2CO crystallizes in the triclinic
space group witha=14.631(6),b=15.258(4),c=18.785(7) Å, =69.66(2), =70.72(1), =88.55(1)°. The crystal structure consists of two independent [Hg(terpy)2]2+ cations, four trifluoromethanesulfonate anions and an acetone molecule in the asymmetric unit. Each mercury atom is coordinated by two tridentate terpyridine ligands forming an irregular six-coordination polyhedron. The Hg–N bond lengths range from 2.27(2) to 2.53(2) Å. 相似文献
39.
A study on the ductile deformation domain of the brittle fault in the shallow level ofthe crust is a new probe field for the modern structural geology. Taking the southern Jiang-su Province area as an example the orientation measurement of quartz crystals, the com-positional texture observation of three pressure sensitive minerals and the rheological param-eter determination of dislocation densities, etc. have been demonstrated and analysed basedon typical samples in the present paper. In addition, their generation mechanisms arealso discussed from the cataclastic rheology, the dynamic differentiation and the simpleshearing, specially, from the Ode strength theory. Finally, a generative relationship betweenthe ductile deformation domain of the brittle fault system, in the regional layer--slip andthe formation of the stratabound ore deposit is shown as well. 相似文献
40.
Preparation and Crystal Structure of LnAl3Br12 (Ln = La, Ce, Pr, Nd, Sm, Gd) and Thermal Decomposition to LnBr3 LnAl3Br12 (Ln = La, Ce, Pr, Nd, Sm, Gd) was prepared in crystalline form for the first time. The crystal structures of LaAl3Br12, PrAl3Br12, and NdAl3Br12 were determined on single crystals by X-ray methods. The isotypic compounds crystallize with trigonal symmetry, space group P 3112, Z = 3. A structural comparison to lanthanoide chloroaluminates of equal composition is given and thermal decomposition of LnAl3Br12 (Ln = Nd) to the corresponding lanthanoide tribromide is described. 相似文献