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991.
Kubota Y Nelson JK Perticone D Poling R Schrenk S Crawford G Fulton R Jensen T Johnson DR Kagan H Kass R Malchow R Morrow F Whitmore J Wilson P Bortoletto D Brown D Dominick J McIlwain RL Miller DH Modesitt M Ng CR Schaffner SF Shibata EI Shipsey IP Battle M Kroha H Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Nemati B Romero V Sun CR Wang P Zoeller MM Goldberg M Haupt T Horwitz N Jain V Mestayer MD Moneti GC Rozen Y Rubin P Skwarnicki T Stone S Thusalidas M Yao W Zhu G Barnes AV Bartelt J 《Physical review D: Particles and fields》1991,44(3):593-600
992.
993.
镓在裸Si系和SiO2/Si系掺杂效应 总被引:3,自引:0,他引:3
Based on the diffusion action of gallium in silicon and SiO2 ,a diffusion model of gallium doping in bare silicon system and SiO_2/Si system is first presented in this paper ,the gallium doping effect in the two systems is analyzed theoretically. Experiments and applications have proved that the use of the open-tube gallium deffusion in SiO2/Si system can substantially improve diffusion quality and device characteristics . 相似文献
994.
995.
Hydrothermal reactions of cadmium(II) chloride with three amino-diphosphonic acids, C6H5CH2N(CH2PO3H2)2 (H4L1), C6H5CH2CH2N(CH2PO3H2)2 (H4L2) and 4-CH3-C6H4CH2N (CH2PO3H2)2) (H4L3) resulted in three new metal amino-diphosphonates, namely, Cd(H3L1)2, 1 Cd(H3L2)2·2H2O 2 and Cd(H3L3)23. In all three complexes, the Cd(II) ion is octahedrally coordinated by six phosphonate oxygen atoms from six ligands. Complexes 1 and 3 have a similar structure in which the CdO6 octahedra are cross-linked by bridging ligands into a double chain along the c-axis, such double chains are further interlinked via hydrogen bonds between non-coordinated phosphonate oxygen atoms to form 〈100〉 and 〈200〉 layers with the phenyl groups of the ligands orientated toward the interlayer space. The structure of complex 2 features a 〈100〉 cadmium(II) diphosphonate layer. The effects of the substitute groups attached to the amine groups on the structures of the metal phosphonates are also discussed. 相似文献
996.
A new sensitive flow injection method for determination of ammonia in natural water samples have been developed, based on the oxidation of ammonia to nitrite by hypochlorite in the presence of large amount of potassium bromide. The oxidant solution obtained by on-line mixing of hypochlorite and potassium bromide was injected into a water carrier stream, and then mixed with sample stream. Ammonia in the sample solution was oxidized to nitrite. Nitrite was then determined by spectrophotometry with sulfanilamide and N-1-naphthylethylenediamine. By reversed injection of the oxidant solution, the interference of nitrite and turbidity of the sample can be removed. The linear range of the method for ammonia is 0.2-12 muM. The proposed method is simple and sensitive. It had been applied to the determination of ammonia in lake water samples. Recoveries of 95-104% were obtained. 相似文献
997.
Chao Chen Yu-Lin Yang Kun-Lin Huang Zhen-Hua Sun Wei Wang Zhuo Yi Yun-Ling Liu Wen-Qin Pang 《Polyhedron》2004,23(18):3033-3042
With a hydrothermal technique, a layered titanium phosphate with the formula Ti2(H2PO4)(HPO4)(PO4)2 · 0.5C6N2H16 (denoted TP-J2) has been prepared by treating the Ti/H3PO4/H2O/1-methylpiperazine system directly. The as-synthesized products were characterized by powder X-ray diffraction, CP-MAS solid-state 31P NMR spectroscopy, thermogravimetric and differential thermal analyses (TG-DTA). The structure was solved by single-crystal X-ray diffraction analysis and it presents an extended γ-phase intercalated with organic amine. Crystal data: triclinic, , a = 8.106 (2) Å, b = 8.197 (2) Å, c = 11.658 (2) Å. = 78.32 (3)°, β = 80.85 (3)°, γ = 77.90 (3)°, Z = 2. Additionally, the intercalation behavior of TP-J2 with n-alkyl monoamine (n = 2, 3, 4, 6, 8, 10 and 12) was investigated. Owing to the strong brønsted base, N,N′-dimethylpiperazine, resides in the interlayer, it presented unusual features of TP-J2 in contrast with that of γ-Tip. 相似文献
998.
Synthesis, Structure and Conductivity of the New Charge-transfer Salt (ET)_2(CH_2=CH-CH_2-SO_3)·H_2O
Zhi LIU Qi FANG* Wen Tao YU Min Hua JIANG De Qing ZHANG Dao Ben ZHU State Key Laboratory of Crystal Materials Shandong University Jinan Institute of Chemistry The Chinese Academy of Sciences Beijing 《中国化学快报》2003,14(4)
ET is one of the most famous electron-donor molecules, which forms charge-transfer complexes (abbr. CT-complexes) with various types of counterions. These complexes have received intense attention because a wide range of physical properties such as conductivity and superconductivity1, ferromagnetism2-4 and nonlinear optical properties5 was found in these materials. Although the majority of the ET-based CT-complexes were prepared by combining with inorganic counterions, CT-complexes with o… 相似文献
999.
Summary A new Schiff base ligand, N,N-bis(l-ferrocenyl-1-oxo-3-methyl)propenylethylenediamine (H2L) and its copper(II), zinc(II), cobalt(II), nickel(II), cadmium(II) and manganese(II) complexes have been prepared, and the structure of the copper complex has been determined by single crystal X-ray techniques and refined to R = 0.041 for 7403 independent reflections. The copper atom is situated in a distorted planar environment. The dihedral angle between planes of two chelating rings which do not contain the metal is 33.5°. Two substituted Cp rings are conjugated with two chelating acacim rings. The iron-centroid forms an angle of 179.4°. The Cp rings are twisted from the eclipsed conformation. 相似文献
1000.
A novel solvent-relief-self-seeding (SRSS) process was applied to grow bulk polygonal tubular single crystals of Sb(2)E(3) (E = S, Se), using SbCl(3) and chalcogen elements E (E = S, Se) as the raw materials at 180 degrees C for 7 days in ethanol solution. The products were characterized by various techniques, including X-ray powder diffraction (XRD), scanning electronic microscope (SEM), transmission electronic microscope (TEM), electronic diffraction (ED), and X-ray photoelectron spectra (XPS). The calculated electrical resistivities of the tubular single crystals in the range 20-320 K were of the order of 10(5)-10(6) Omega cm for Sb(2)S(3) and 10(3)-10(4) Omega cm for Sb(2)Se(3), respectively. The studies of the optical properties revealed that the materials formed had a band gap of 1.72 eV for Sb(2)S(3) and 1.82 eV for Sb(2)Se(3), respectively. The optimal reaction conditions for the growth of bulk tubular single crystals were that the temperature was not lower than 180 degrees C and the reaction time was not shorter than 7 days. The possible growth mechanism of tubular crystals was also discussed. 相似文献