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Spectroscopic identification towards tunable mesoscale aggregates of zinc tetraphenylporphyrin for materials

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Chinese Chemical Letters 2018年第3期29卷 361-365页

作者： Pan An Longtian Kang Zhen Tang Peifeng Su Zhixun Luo state Key laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Belting 100190 China Fujian Institute of Research on the Structure of Matter Fujian Chinese Academy of Sciences Fuzhou 350002 China state Key laboratory of Physical Chemistry of solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

We present a study of spectroscopic identification towards the molecular aggregates of zinc tetraphenylporphyrin （ZnTPP） illustrating how the energy states and intermolecular interactions determine the tunable properties of functional materials in condensation processes. Distinguishable fingerprints of ZnTPP nanorods and nanosheets are addressed utilizing X-ray diffraction （XRD）, Raman and UV-vis absorption spectroscopies. Although these ZnTPPs are assigned to J-aggregation at different extent, the spectral analysis reveals a significant role of the intermolecular interactions associated with varying mesoscale architectures. Energy decomposition analysis （EDA） revealed that the varied ZnTPP aggregates are stabilized by altered dispersion interactions due to the dominant ~r...zr stacking between the monomers.

关键词： ZnTPP Molecular aggregates Intermolecular interactions Ramanspectroscopy XRD

NEW SOLUTION SYSTEM FOR CIRCULAR SECTOR PLATE BENDING AND ITS APPLICATION

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Acta Mechanica solida Sinica 1999年第4期12卷 307-315页

作者： Yao, W Zhong, WX Su, B Dalian Univ Technol State Key Lab Struct Anal Ind Equipment Dalian 116023 Peoples R China

Instead of the biharmonic type equation, a set of new governing equations and solving method for circular sector plate bending is presented based on the analogy between plate bending and plane elasticity problems. So the Hamiltonian system can also be applied to plate bending problems by introducing bending moment functions. The new method presents the analytical solution for the circular sector plate. The results show that the new method is effective.

关键词： circular sector plate Hamiltonian system bending moment functions analogy

Advances in interspecific pregnancy

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Chinese Science Bulletin 2001年第21期46卷 1772-1778页

作者： Xichao Wang Bojie Dai Enkui Duan Dayuan Chen Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

Interspecific pregnancy in which the conceptus and female carrying the pregnancy are of different species is a key step to interspecific cloning. Cloning endangered animals by interspecific pregnancy is such a highlight catching people’s eyes nowadays. In this article, the history of interspecific pregnancy, the methods for establishment of interspecific pregnancy, the corresponding theories, barriers and applied prospects are reviewed.

关键词： interspecific pregnancy cloning reproduction.

Optically stimulated luminescence of Dy^3+-doped NaCaPO4 glass-ceramics

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Journal of Rare Earths 2020年第9期38卷 927-932,I0001页

作者： Jie Xu Zhaoyang Chen Minqiang Gai Yanwei Fan Chengfa He Key laboratory of Functional Materials and Devices for Special Environments of CAS Xinjiang Key Laboratory of Electronic Information Materials and DevicesXinjiang Technical Institute of Physics and Chemistry of CASUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China laboratory of solid state Radiation Physics Urumqi 830011China

Dy^3+-doped glass-ceramics containing NaCaPO4 crystals were successfully fabricated by heat treatment at base glass,and the luminescence properties were investigated for potential applications in radiation *** photo luminescence(PL)excitation and emission spectra exhibit transitions related to Dy^3+ions corresponding to the strongest excitation and emission wavelengths at 351 and 575 nm,*** CW-OSL properties as a function of dopant concentration,pre-heating temperature,pre-heating time and signal fading were *** most appropriate Dy^3+ion concentration was found to be 0.25 mol%.The TL glow curves have a broad peak feature peaking at 195±5℃.The fading of the OSL signal would keep stable in five days with the intensity value of about 76.11%.The samples also exhibit good signal reusability and a broad linear dose response range(0.02-1000 Gy).

关键词： Optically stimulated luminescence Glass-ceramics Radiation measurements Photoluminescence Rare earths

solid Reference Electrode of Metallurgical Oxygen Sensor

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Journal of Iron and Steel Research International 2006年第5期13卷 18-20,46页

作者： LOU Tian-jun KONG Xiang-hua HUANG Ke-qin LIU Qing-guo Department of Chemistry and Engineering Henan Institute of Science and Technology Xinxiang 453003 Henan China Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China laboratory for solid state Ionics University of Science and Technology Beijing Beijing 100083 China

The thermal equilibrium state of the reference electrode was investigated. The results show that the temperature difference between the inside and the outside of zirconia tube was very small and the Seebeck effect can be ignored after the sensor was dipped into liquid steel for more than 2 s. A special sensor was designed to test the relation between the EMF （electromotive force） of sensor and the thermal equilibrium state of the reference elec- trode. Based on these results, it is suggested that the peak in EMF curve was caused by the change of oxygen potential in reference electrode before the thermal equilibrium was reached. If NiO was added by 2 M- 5 M to the Cr/Cr2O3 reference electrode, the peak in EMF curve could be eliminated.

关键词： ZrO2 solid electrolyte oxygen sensor reference electrode

Simulated human eye retina adaptive optics imaging system based on a liquid crystal on silicon device

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Chinese Physics B 2008年第12期17卷 4529-4532页

作者：姜宝光曹召良穆全全胡立发李超宣丽 state Key lab of Applied Optics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of sciences Graduate School of the Chinese Academy of Sciences

In order to obtain a clear image of the retina of model eye, an adaptive optics system used to correct the wave-front error is introduced in this paper. The spatial light modulator that we use here is a liquid crystal on a silicon device instead of a conversional deformable mirror. A paper with carbon granule is used to simulate the retina of human eye. The pupil size of the model eye is adjustable （3-7mm）. A Shack-Hartman wave-front sensor is used to detect the wave-front aberration. With this construction, a value of peak-to-valley is achieved to be 0.086 A, where A is wavelength. The modulation transfer functions before and after corrections are compared. And the resolution of this system after correction （691p/m） is very close to the diffraction limit resolution. The carbon granule on the white paper which has a size of 4.7μm is seen clearly. The size of the retina cell is between 4 and 10 μm. So this system has an ability to image the human eye＇s retina.

关键词： liquid crystal device adaptive optics ophthalmic optics

Expression of steroidogenic acute regulatory protein and its regulation by interferon-gamma in rat corpus luteum

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Chinese Science Bulletin 2000年第23期45卷 2152-2157页

作者： Hongjuan Gao Xinlei Chen Lei Shi Yixun Liu Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

The steroidogenic acute regulatory protein (StAR) is the key regulatory protein of steroidogenesis. De novo synthesis of StAR protein is required for intramitochondrial translocation of cholesterol to the cytochrome P450 side chain cleavage enzyme which is located on the matrix side of the inner mitochondrial membrane. This is the rate-limiting step of steroid biosynthesis. Using in situ hybridization and immunohistochemistry we studied StAR expression in various stages of the corpora luteal and its regulation by interferon-gamma (IFNγ) in the adult pseudopregnant rat. The results indicated that expression of StAR in the corpora luteal was correlated with progesteron production and IFNγ was capable of inhibiting its expression.

关键词： corpus luteum StAR in situ hybridization immunohistochemistry IFNγ.

Hydrothermal Synthesis and Crystal Structure of Trioxomolybdate: NaH_3OMo_3O_(10)

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Chinese Journal of Structural Chemistry 2001年第4期20卷 266-269页

作者：吴传德林祥等 Chinese Acad Sci Fujian Inst Res Struct Matter State Key Lab Struct Chem Fuzhou 350002 Fujian Peoples R China

The hydrothermal reaction of Na2MoO4?2H2O, SmCl3 in acidified H2O/CH3CN solution gives rise to the title compound as colorless needle crystals, which was characterized by elemental analysis, IR and X-ray single-crystal diffraction techniques. Crystallographic data: Orthorhombic, Pnma, H3Mo3NaO11, Mr = 489.83, a = 8.411（2）, b = 7.566（2）, c = 14.359（3） ?, V = 913.8（3） ? 3, Z = 4, Dc = 3.560 g·cm-3, ( = 4.148 mm-1, F（000） = 912, the final R = 0.0649 and wR = 0.1569 for 1885 observed reflections with I ≥ 2σ（I）. The title compound consists of infinite chains built up by distorted {MoO6} octahedra via edge sharing, which are further connected into a three-dimensional framework by sodium ions and protoned water molecules.

关键词： trioxomolybdate templating effects hydrothermal synthesis structure

Oxygen-vacancy-related dielectric relaxation and conduction mechanisms in Bi5TiNbWO15 ceramics

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Chinese Physics B 2007年第7期16卷 2131-2135页

作者：王晓娟龚志强钱亚峰朱骏陈小兵 College of Physics Science and Technology Yangzhou University Yangzhou 225002 China The National laboratory of solid state Microstructure Nanjing University Nanjing 210008 China

This paper reports that the intergrowth ceramics Bi5TiNbWO15 （BW-BTN） have been prepared with the conventional solid-state reaction method. The dielectric and conductivity properties of samples were studied by using the dielectric relaxation and AC impedance spectroscopy in detail. Two distinct relaxation mechanisms were detected both in the plots of dielectric loss （tanδ） and the imaginary part （Z″） versus frequency in the frequency range of 10 Hz-13 MHz. We attribute the higher frequency relaxation process to the hopping process of the oxygen vacancies inside the grains, while the other seems to be associated with the space charges bound at the grain boundary layers. The AC impedance spectroscopy indicates that the conductivities at 625 K for bulk and grain boundary are about 1.12 × 10^-2 S/m and 1.43 × 10^-3 S/m respectively. The accumulation of the space charges in the grain boundary layers induces a space charge potential of 0.52 eV.

关键词： intergrowth dielectric relaxation impedance spectroscopy oxygen vacancies