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Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials International 2007年第6期17卷 639-644页

作者： Liu Xiao1.2.and Xu Jiyao1.1. State Key Laboratory for Space Weather, Center for Space Science and Applied Research, chinese {1. of Sciences, {2. 1.0080, China 2. Graduate University of chinese {1. of Sciences, {2. 1.003., China) [a]State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]Graduate University of chinese {1. of Sciences Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

Study on growth and properties of novel γ-LiAlO_2.substrate

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Science China(Technological Sciences) 2006年第2期49卷 188-193页

作者： ZOU Jun1.2. ZHOU Shengming1. XU Jun1.& ZHANG Rong3.1. Shanghai Institute of Optics and Fine Mechanics, {1. academy of Sciences, Shanghai 2.1.00, China 2. Graduate School of {1. academy of Sciences, beijing 1.003., China 3. Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 2.0}093. China 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of chinese {1. of Sciences Beijing 100039 China 3. Laboratory of Solid State Microstructures and Department of Physics Nanjing University Nanjing 210093 China

Transparent γ-LiAlO2.single crystal has been grown by Temperature Gradient technique. The surface of the wafer annealed in O2.atmosphere at 1.00°C for 70 h became opaque and Li-poor phase (LiAl5O8); while, that annealed in Li-rich atmosphere kept transparent and smooth. The full-width at half maximum value dropped to 3. arcsecs when the wafer was annealed in Li-rich atmosphere. That annealed in O2.atmosphere increased to 78 arcsec. Compared with absorption spectra, we can conclude that the 1.6 nm absorption peak was caused by Li vacancies and the 73. nm peak was caused by O vacancies.

关键词： γ-LiAlO2 crystal, scanning electron micrograph (SEM), absorption spectra.

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1.2., GUO Qionglin~1.*, HU Wei~1. WANG Yaping~1.and ZHU Zuoyan~1.1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, chinese {1. of Sciences, Wuhan 43.072. China 2. Graduate School of chinese {1. of Sciences, beijing 1.003., China) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]Graduate School of chinese {1. of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1.06 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 3.4 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 3.1.bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 3.1.bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

Approximation of dense-n/2.subgraph and table compression problems

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Science China Mathematics 2005年第9期48卷 1223-1233页

作者： XU Dachuan~1.HAN Jiye~2.& DU Dongle~3.1. College of Applied Sciences,{1. University of Technology,{1. 1.002.,China 2. Institute of Applied Mathematics,{2. of Mathematics and Systems Science,{3. {2. of Sciences,{1. 1.0080,China 3. Faculty of Administration,University of New Brunswick,P.O.Box 4400,Fredericton,NB E3. 5A3.Canada College of Applied Sciences Beijing University of Technology Beijing 100022 China Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2.subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5982.and 0. 5970-approximation algorithms respec- tively for the dense-n/2.subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 62.3.and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2.subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

Cloning and characterization of interferon stimulated genes Viperin and ISG1.,and their promoters from snakehead Channa argus

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Progress in Natural Science:Materials International 2007年第12期17卷 1425-1435页

作者： Jia Weizhang1.2. Zhou Xiuxia1.2. Huang Rong1.2.and Guo Qionglin1.1. Institute of Hydrobiololgy, chinese {1. of Sciences, Wuhan 43.072. China 2. Graduate University of chinese {1. of Sciences, beijing 1.003., China) Institute of Hydrobiololgy Chinese Academy of Sciences Wuhan 430072 China Graduate University of chinese {1. of Sciences Beijing 100039 China

By suppression subtractive hybridization, rapid amplification of cDNA ends and gene walking methods, interferon stimulated genes (ISGs), Viperin and ISG1., and their promoters have been cloned and characterized from snakehead Channa argus. The Viperin cDNA was found to be 1.74 nt and contain an open reading frame (ORF) of 1.59 nt that translates into a putative peptide of 3.2.amino acid (aa). The putative peptide of Viperin shows high identity to that in teleosts and mammals except for the N-terminal 70 aa. The ISG1. cDNA was found to be 758 nt and contain an ORF of 468 nt that translates into a putative peptide of 1.5 aa. The putative peptide of ISG1. is composed of two tandem repeats of ubiquitin-like (UBL) domains, and a canonical conjugation motif (LRGG) at C-terminal. Viperin and ISG1. promoter regions were characterized by the presence of interferon stimulating response elements (ISRE) and γ-IFN activation sites (GAS). ISRE is a feature of IFN-induced gene promoter and partially overlaps interferon regulatory factor (IRF) 1.and IRF2.recognition sites. GAS is responsible for the γ-IFN mediated transcription. One conserved site for NF-κB was found in the promoter region of Viperin. This is the first report of conservative binding motif for NF-κB in accordance with the consensus sequence (GGGRNNYYCC) among teleost ISG promoters. Moreover, there were also TATA, CAAT and Sp1.transcription factor sites in Viperin and ISG1. promoters. In 5′ untranslated region (UTR), snakehead ISG1. gene contains a single intron, which differs from Viperin gene. The transcripts of Vipeirn and ISG1. mRNA were mainly expressed in head kidney, posterior kidney, spleen and gill. The expression levels in liver were found to increase obviously in response to induction by IFN-inducer poly I∶C.

关键词： interferon interferon stimulated gene (ISG) Viperin ISG1. snakehead (Channa argus).

Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest China:Evidence from sandstone detrital and geochemical records

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Science China Earth Sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1. GUO Hong2. WANG Daoxuan3.& LIN Wei1.1. Institute of Geology and Geophysics, {1. academy of Sciences, {2. 1.002., China 2. Tarim Oilfield Branch, CNPC, Korla 841.00, China 3. Hefei University of Industry, Tunxilu 1.3. Hefei 2.1}009, China 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing Chin 2. Tarim Oilfield Branch CNPC 841000 Korla China 3. Hefei University of Industry Tunxilu 193 230009 Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest China, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1. From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2. For major element geo- chemical parameters of whole sandstones, CaO and Fe2.O * 3.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. (3. Contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2.3.(CaO+Na2.) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-Cenozoic.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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Science China Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1.2. TAO Mingxin2.3.& YE Xianren2.1. {1.s and Environmental School, Lanzhou University, Lanzhou 73.000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, chinese {2. of Sciences, Lanzhou 73.000, China 3. College of {1.s Science & Technology, beijing Normal University, beijing 1.0875, China 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of {1.s Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 1.~9 to 1.50 x 1.~9,N_2.Ar from 92. to 5661., and N_2.~3.e from 2.5 x 1.~9 to 2. x 1.~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

A new principle of synthetic cascade utilization of chemical energy and physical energy

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Science China(Technological Sciences) 2005年第2期48卷 163-179页

作者： JIN Hongguang1. HONG Hui1.2. WANG Baoqun1.2. HAN Wei1.2.& LIN Rumou1.2.1. Institute of Engineering Thermophysics, chinese {1. of Sciences, {2. 1.0080, China 2. Graduate School of the chinese {1. of Sciences, {2. 1.003., China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese {1. of Sciences 100039 Beijing China

We propose a new principle of the cascade utilization of both chemical energy and physical energy in energy systems with the integration of chemical processes and thermal cycles. Particularly, a general equation of energy levels of substance, Gibbs free energy of chemical reaction and physical energy is explicitly founded. On the basis of this equation, a chemical-looping combustion and an indirect combustion are investigated. Furthermore, a mechanism of energy release, with the combination of decreasing the energy level of Gibbs free energy and upgrading the energy level of low or middle- temperature thermal energy, is clarified. The promising results obtained here establish a theoretical basis for the further investigation of multi-function systems in which energy and the environment are compatible, and create a new approach to improve the performance of traditional thermal cycles.

关键词： chemical energy, cascade utilization, exergy, energy conversion.

Bio-regeneration of p-complexation desulfurization adsorbents

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Science China Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1.2. XING Jianmin1. XIONG Xiaochao1.2. SHAN Guobin1.2.& LIU Huizhou1.1. Laboratory of Separation Science and Engineering, Institute of Process Engineering, chinese {1. of Sciences, {2. 1.0080, China 2. Graduate School of the chinese {1. of Sciences,{2. 1.003., China 1. Laboratory of Separation Science and Engineering Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese {1. of Sciences 100039 Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2. and then by auto-reduction in helium at 450℃ for 3.h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2.HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2.HBP within 6 h and almost 1.0% within 2. h, when the volume ratio of oil-to-water was 1.5 mL/mL, the cell concentration was 60 g·L?1. and the ratio of adsorbent-to-oil was 0.03.g·mL?1. The amount of 2.HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 1.0℃ for 2. h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.