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991.
Syntheses,Structural Characterization and Thermoanalysis of Transition-Metal Compounds Derived from 3,5-Dinitropyridone 总被引:1,自引:0,他引:1
Rong Fan Qiu-Ping Zhou Guo-Fang Zhang Mei-Yu Cai Ping Li Li-Hua Gan Feng-Qi Zhao Ji-Zhen Li Xue-Zhong Fan Seik Weng Ng 《Journal of chemical crystallography》2010,40(3):266-271
Abstract
Nine metal compounds of Mn(II), Zn(II) and Cd(II) derived from dinitropyridone ligands (3,5-dinitropyrid-2-one, 2HDNP; 3,5-dinitropyrid-4-one, 4HDNP and 3,5-dinitropyrid-4-one-N- hydroxide, 4HDNPO) were characterized by elemental analysis, FT-IR and partly by TG-DSC. Three of which were further structurally characterized by X-ray single-crystal diffraction analysis. The structures of the three compounds, Mn(4DNP)2(H2O)4, 4, Zn(4DNPO)2(H2O)4, 8, and Cd(4DNPO)2(H2O)4, 9, crystallize in the monoclinic space group P2(1)/n and Z = 2, with a = 8.9281(9), b = 9.1053(9), c = 10.6881(11) Å, β = 97.9840(10)° for 4; a = 8.4154(7), b = 9.9806(8), c = 10.5695(8) Å, β = 97.3500(10)° for 8; a = 8.5072(7), b = 10.2254(8), c = 10.5075(8) Å, β = 96.6500(10)° for 9. All three complexes are octahedral consisting of four equatorial water molecules, and two nitrogen or oxygen donor ligands (DNP or DNPO). The abundant hydrogen-bonding and π-π stacking interactions seem to contribute to stabilization of the crystal structures of the compounds. The TG-DTG results revealed that the complexes showed a weight loss sequence corresponding to all coordinated water molecules, nitro groups, the breaking of the pyridine rings and finally the formation of metal oxides. 相似文献992.
993.
Solid-state dye samples based on modified polymethyl methacrylate with methanol (MPMMA) doped with pyrromethene 567 (PM567)
were first prepared. The effects of volume percentage of methanol on the laser performances of the samples, including spectra
properties, slope efficiency and photostability were studied. The highest slope efficiency 66.39% was obtained in the sample
(MMA:methanol = 16:4). Pumping the samples at a repetition rate of 5 Hz with a pulse energy as high as 100 mJ (the fluence
was 0.26 J/cm2), the output energy dropped to half of its initial value after approximate 156720 shots and the corresponding normalized
photostability reached 101.86 GJ/mol in the sample (MMA:methanol = 17:3). Our results indicate that it can obtain a high slope
efficiency and good photostability for a solid-state dye laser using MPMMA as solid hosts. 相似文献
994.
Wang X. Li P. Yang H. Jiang T. Ma Y. Fan Z. Niu G. Yu J. Wang A. Zhang Z. 《Laser Physics》2011,21(11):1941-1944
An all-fiber high-energy nonlinear chirped-pulse amplification system with two-stage double-cladding fiber amplifiers is presented
in this paper. It generates pulses with the energy up to 10 μJ at 20 kHz repetition rate and total accumulated nonlinear phase
shift as large as 12.8π. The pulses can be compressed to 137 fs with the compensation of mismatched third-order dispersion
by self-phase modulation in the fiber amplifiers. 相似文献
995.
A passively Q-switched 1.06 μm laser with Cr4+:YAG saturable absorber by direct 879 nm diode pumping grown-together composite GdVO4/Nd:GdVO4 crystal to the emitting level was demonstrated in this paper. The characteristics of pulsed laser were investigated by using
two kinds of Cr4+:YAG crystal with the initial transmissivity of 80 and 90%, respectively. When the T
0 = 90% Cr4+:YAG was used, an average output power of 1.59 W was achieved at an incident pump power of 10 W. The pulse width and repetition
rate were 64.5 ns and 170 kHz, respectively. The thermal lens effect of laser crystal was analyzed. 相似文献
996.
X. L. Zhang X. Y. Zhang Q. P. Wang C. Wang H. H. Xu Y. Tang L. Li Z. J. Liu X. H. Chen S. Z. Fan Z. T. Jia X. T. Tao 《Laser Physics》2011,21(6):1047-1050
A diode-side-pumped continuous-wave Nd:GGG laser operating at dual-wavelength (1110 and 1105 nm) and single wavelength of 1110 nm is demonstrated for the first time. The maximum output power of the 1110 and 1105 nm dual-wavelength operation is 13.2 W. By adjusting the orientation of an insertion mirror, the relative intensities of the two wavelengths can be changed. Thus single wavelength operation at 1110 nm is obtained, and the output power is 9.6 W. 相似文献
997.
Fabien Durand Ai-Hua Fan Andrei Yu. Khrennikov Dongdai Lin Franco Vivaldi Yuefei Wang 《P-Adic Numbers, Ultrametric Analysis, and Applications》2011,3(4):359-362
On the occasion of the 60th birthday of Professor Vladimir Sergeevich Anashin, we present a review of his significant scientific
research and related activities. 相似文献
998.
Ye-jun Xu Jun Song Hong-yi Fan Qiu-yu Liu 《International Journal of Theoretical Physics》2011,50(3):744-751
By virtue of deformation quantization methods we introduce the q-deformed coordinate representation. A new set of completeness and orthogonality relations composed of the ket and bra which
are not mutually Hermitian conjugates are derived. Further, using the eigenket and eigenbra for q-deformed coordinate some important quantum gate operators for continuum variables are realized and their properties are discussed. 相似文献
999.
Zhengang Lu Jiubin Tan Jing Qi Zhigang Fan Luyang Zhang 《Optics Communications》2011,284(16-17):3855-3861
In order to analyze the Fraunhofer diffractive characteristics and modulation transfer function (MTF) of a tilted ring metallic mesh, an optical intensity distribution model of Fraunhofer diffraction is built using Huygens–Fresnel diffraction theory and the diffraction integral is carried out directly in the tilted mesh plane. The diffraction characteristics of the tilted ring metallic mesh are in good agreement with experimental results, which proves the correctness of the model established. MTF of an optical system with metallic mesh is calculated based on the model established and Fourier transform. Analysis shows that the degradation of MTF caused by diffraction of a ring mesh is much less than that of a square mesh whether they are vertical or tilted to the optical axis. Therefore, ring mesh can provide higher imaging quality than square mesh when they are used as high-pass filters in optical windows. A tilted array diffraction modulating factor is abstracted and believed useful in the analysis of diffractive characteristics of tilted square mesh and ring mesh, and it can be extended to Fraunhofer diffractive characteristics analysis of other tilted diffraction arrays. 相似文献
1000.
A class of active fiber is presented as gain mediums of fiber lasers, where a silica layer with spoke-like air slits is introduced between the active core and cladding to obtain birefringence. With an appropriate choice of the design parameters, the fiber can support only the HE11 and TM01 modes. Furthermore, the numerical results show that, corresponding to the optimal rare earth doping profile, the fiber lasers can output a pure TM01 mode with about 79% slope efficiency without using other mode-selective elements. 相似文献