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Open Journal of Inorganic Chemistry 2012年第1期2卷 6-11页

作者： Yunsheng Hu Weidong Zhuang Jianhua Hao Xiaowei Huang Huaqiang He 不详

Sr2SiO4: Eu phosphor for white light emitting diodes (LEDs) was synthesized by employing an as-prepared (Sr, Eu)CO3@SiO2 core-shell precursor as starting materials, and the effect of the core-shell precursor was also discussed on the crystal structure, particle morphology and luminescent properties of the resultant phosphor. The results showed that the hybrid β- and α′-Sr2SiO4: Eu phosphor with fine particle size and narrow distribution could be obtained at a lower firing temperature than that in conventional solidstate reaction method, and its formation mechanism was deduced to be (Sr, Eu)CO3 diffusion controlled reaction process. Responded to its hybrid crystal structure, this phosphor exhibited the combined luminescence of β- and α′-Sr2SiO4: Eu.

关键词： Phosphor precursor Core-Shell Structure Preparation Mechanism Luminescence

Research on Earthquake precursor Attractor and Its Predictability

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Earthquake Research in China 1999年第3期13卷 60-66页

作者： Li QiangSeismological Bureau of Jiangsu Province, Nanjing 210014, China

Based on the body strain observation data at Liyang and Xuzhou stations, the Correlation Dimension D2 and the second-order Renyi entropy K2 of the attractor are calculated and studied. In addition, a new method of evaluating the longest predictable time of precursor attractor is advanced under the condition of a certain anomalous criterion rule. The conclusion indicates that the body strain precursor attractor is one of the chaotic attractors and it has some determinate change rules such as the dimension declines before an earthquake and the number of the independent factors on which the variation of the system depends is within the range of 5 - 12. The conclusion also indicates that the longest evaluated predictable time of the body strain attractor is 213 days at the Liyang station and 342 days at the Xuzhou station. It is clear that this research can be of great reference value for recognizing the nonlinear behavior of precursor attractors and for evaluating the predictability of different

关键词： precursor Fractal Entropy Earthquake prediction.

Exploring E Turkey: Rainfall precursor Predicts 100% Earthquake in a Consistent Manner in Just 2 Weeks

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International Journal of Geosciences 2013年第4期4卷 759-765页

作者： Prakash Pillai SQS Institute of NDT Super Quality Services Tiruchi Tamilnadu India

Rainfall event is the very specific, reliable unambiguous precursor for the earthquake event. Over the years scientists have hunted for some signal—a precursory sign, however faint—that would allow forecasters to pin-point exactly where and when the big ones will hit. After decades spent searching in vain, many seismologists now doubt whether such a signal even exists. But in a great surprise to everyone, from an ordinary lay man to eminent scientists, 100% earthquakes occur after rainfalls! Though I have the findings for the entire regions of the world, here E Turkey are the region for submission for the period Jan-November, 2012 to study the strong correlation and show the strong evidence to prove that the 100% earthquakes after rainfall in a consistence manner. Anyone can very easily verify the validity of the findings for any forthcoming earthquakes for any regions of E Turkey in just two weeks of period. Nature does not give two different results for the same phenomena, for two different observers. Though there exists a very strong relation between the rainfalls and the earthquakes, scientists and seismologists have not been able to detect and identify this rainfall precursory signal for hundreds of years that consistently occurs before earthquakes. The methodology of rainfall event before earthquakes, even works consistently for earthquake prediction purpose, especially in any regions of the world. Rainfall type precursor is the best approach to predict specific earthquakes, which provide the potential for estimating the epicenter and magnitude of any moderate to strong earthquakes. Earthquakes are more likely when there is rain than it is not. The magnitudes of a resulting individual earthquake depend on the severity of the weather changes. However, in a very few cases the time scales and magnitude do vary substantially as a consequence of local site geology and other factors.

关键词： Earthquake Prediction Earthquake precursor Rainfall Predicts Earthquakes Weather Predicts Earthquakes

Low-Temperature Synthesis of Nanocrystalline Mn0.2Ni0.8Fe2O4by Oxalate precursor Route

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Advances in Materials Physics and Chemistry 2013年第1期3卷 1-7页

作者： Mahmoud M. Hessien Zaki I. Zaki Al-Qahtani Mohsen Department of Chemistry Faculty of Science Taif University Taif KSA

Manganese nickel ferrite (Mn0.2Ni0.8Fe2O4) powder was synthesized through oxalate precursor route. The effect of annealing temperature (400℃ - 1100℃) on the formation, crystalline size, morphology and magnetic properties was systematically studied. The resultant powders were investigated by thermal analyzer (TG-DTG-DSC), X-ray diffractometer (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). Based on thermal analysis results, the oxalate mixture decomposed thermally in multisteps weight loss up to about 680℃. XRD indicated that Mn0.2Ni0.8Fe2O4 formed at much lower annealing temperature (≤400℃) but contained α-Fe2O3 impurity. The hematite phase decreased by increasing the annealing temperature. The lattice parameters were increased with increasing annealing temperature up to 1000℃. The average crystalline size increased by increasing the annealing temperature. Single well crystalline ferrite was obtained at 800℃with crystallite size about 109 nm. The saturation magnetization of the ferrites powders continuously increased with the increase in annealing temperature. Maximum saturation magnetization 48.2 emu/g was achieved for the formed Mn0.2Ni0.8Fe2O4 phase at annealing temperature 1100℃.

关键词： Ni-Mn Ferrite Crystal Structure Soft Magnets Oxalate precursor Route Magnetic Properties

Secretory expression of α single-chain insulin precursor in yeast and its conversion into human insulin

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Science China(Life Sciences) 1996年第3期39卷 225-233页

作者：张友尚胡红明蔡若蓉冯佑民朱尚权贺潜斌唐月华徐明华许英镐张新堂刘滨梁镇和 State Key Laboratory of Molecular Biology Shanghai Institute of Biochemistry Chinese Academy of Sciences Shanghai 200031 China) Shanghai Institute of Biochemistry Chinese Academy of Sciences Shanghai 200031 China.

A synthetic single-chain porcine insulin precursor (PIP) gene and an α-mating factor leader sequence (αMFL) gene obtained by the PCR method are inserted between the promoter and 3’-terminating sequence of the alcohol dehydrogenase gene ADH1 in plasmid pVT102-U to form plasmid pVT102-U/α MFL-PIP. The single-chain insulin precursor is expressed and secreted to the culture medium by Saccharomyces cererisiae transformed by pVT102-U/αMFL-PIP. The precursor is purified and converted into human insulin by tryptic transpeptidation. The purified human insulin is fully active and can be crystallized. The overall yield of human insulin is 25 mg per liter of culture medium.

关键词： human insulin insulin precursor secretary expression Saccharomyces cerevisiae.

Analysis on Depth Distribution and precursor Mechanism of Small and Moderate Earthquakes

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Earthquake Research in China 2001年第4期15卷 406-411页

作者： Wang JianInstitute of Geophysics, China Seismological Bureau, Beijing 100081, China Institute of Geophysics China Seismological Bureau Beijing 100081 China

In this paper, the focus depth distribution of earthquakes with each magnitude has been analyzed. Statistic data show that the lower magnitude is, the wider focus depth distributes. With larger magnitude, the focus tends to be concentrated in upper or middle crustal layers. We analyzed the cause of focus depth distribution and explained the precursor mechanism of small and moderate earthquakes with occurring condition and characteristics of strong earthquakes. The results of this paper may be applied to determine risk sites of strong earthquakes.

关键词： Seismicity Depth distribution precursor Long- and medium-term earthquake prediction

Biophysical and biorheological studies on the precursor cells at different stages

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Science China(Life Sciences) 2002年第4期45卷 421-428页

作者：王金华孙大公姚伟娟曾柱严宗毅文宗曜 Department of Medical Physics Basic Medical School of Peking University Beijing 100083 China

Splenic erythroblasts were obtained from mice during the acute disease caused by anemia-inducing virus (FVA). They were cultured in a medium containing EPO, BSA and so on. We studied their biomechanical and hemorheological behavior after 12 h, 24 h and 48 h. The results showed obvious changes in their electrophoretic mobility, osmotic fragility, membrane fluidity and membrane viscoelastic properties with the development of erythroblast. The changes were associated with the interactions of the protein and lipid and the elements of the membrane.

关键词： precursor cell, electrophoretic mobility, osmotic fragility, membrane fluidity, membrane viscoelastic properties.

MOCVD of Molybdenum Sulphide Thin Film Via Single Solid Source precursor Bis-(Morpholinodithioato-s,s’)-Mo

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Journal of Modern Physics 2011年第5期2卷 341-349页

作者： Bolutife Olofinjana Gabriel Egharevba Bidini Taleatu Olumide Akinwunmi Ezekiel Oladele Ajayi 不详

A single solid source precursor bis-(morpholinodithioato-s,s’)-Mo was prepared and molybdenum sulphide thin film was deposited on sodalime glass using Metal Organic Chemical Vapour Deposition (MOCVD) technique at deposition temperature of 420?C. The film was characterized using Rutherford Backscattering Spectroscopy (RBS), Ultraviolet-Visible Spectroscopy, Four point probe technique, Scanning Electron Mi-croscopy (SEM), X-ray Diffractometry (XRD) and Atomic Force Microscopy (AFM). A direct optical band gap of 1.77 eV was obtained from the analysis of the absorption spectrum. The sheet resistance was found to be of the order of 10P–5P ΩP–1P?cmP–1P. SEM micrographs of the films showed the layered structure of the film with an estimated grain size that is less than 2 μm while XRD indicates parallel orientation of the basal plane to the substrate surface.

关键词： Molybdenum Sulphide precursor Metal Organic Chemical Vapour Deposition (MOCVD) Thin Film Characterization

Deposition and Characterisation of Nitrogen-Doped Zinc Oxide Thin Films by MOCVD Using Zinc Acetate—Ammonium Acetate precursor

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Journal of Modern Physics 2012年第8期3卷 652-659页

作者： U. S. Mbamara O.O. Akinwumi E.I. Obiajunwa I.A.O. Ojo E.O.B. Ajayi Centre for Energy Research and Development Obafemi Awolowo University Ile-Ife Nigeria Department of Chemistry Obafemi Awolowo University Ile-Ife Nigeria Department of Physics Federal University of Technology Owerri Nigeria Department of Physics Obafemi Awolowo University Ile-Ife Nigeria

The synthesis and comprehensive analysis of nitrogen-doped zinc oxide thin films grown from a compound precursor of zinc acetate and ammonium acetate has been reported. The precursor was processed in different ratios of the zinc acetate-ammonium acetate additives, and each combination was used to deposit a thin film using metalorganic chemical vapour deposition (MOCVD) method. The produced thin films were characterised using Rutherford backscattering (RBS) spectroscopy, uv-visible spectrometry, x-ray diffractometry, four point probe measurements and optical microscopy. The deposited thin films showed a fairly consistent zinc:oxygen:nitrogen ratio of 4.4:3.7:1, the film structures were quasicrystalline and the sheet resistivities were high, while other familiar characteristics like optical transmittance, bandgap, thermal stability, etc. were maintained in the grown films. Applications in device fabrication and active sensor devices were hence envisaged as the emergent potentials of the thin films.

关键词： Zinc Oxide Thin Films N-Doping precursor Characterisation

Development of neural precursor cells from mouse embryonic stem cells

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Journal of Medical Colleges of PLA(China) 2001年第4期16卷 274-277页

作者：吴旋黎海蒂李树浓徐海伟徐令 Department of Physiology Third Military Medical University Chongqing 400038 China Department of Pathophysiology Sun Yat-sen University of Medical Sciences Guangzhou 510089 China Department of Medicine Beth Israel Deaconess Hospital Harvard Medical School USA

Objective:To exploretheserum-freecultureconditionsfordifferentiatingmouseembryonicstemcells(ES cells)intoneuralprecursorcells(NPC)andcomparetheeffectsof humanembryonicfibroblasts(HEF)as thefeederlayer of ES withthatof mouseembryonicfibroblasts(MEF)in vitro.Methods:MouseES cellswereculturedin or notin feederlayer cellsmediumcontainingor notleukemiainhibitoryfactorto suppresstheirdifferentiation.Immunocytochemicalmethod was usedto identifyNPCby detectingnestinantigenandalkalinephosphatase.Results: TheES cellsculturedin HEF werepositiveto alkalinephosphatase.Serum-freemediumallowedthedifferentiationof ES cellsintoNPC.Conclusion:HEFcouldreplaceMEFandkeeptheundifferentiatedconditionof ES cellswithmorebenefits.NPCof highpuritycould be culturedfromEScellsby serum-freeculturemethod.

关键词： embryonic stem cell neural precursor cell serum-free culture human embryonic fibroblast