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鼎湖山木荷(Schima Superba)粗死木质残体的分解研究

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山地学报 2009年第4期27卷 442-448页

作者：杨方方李跃林刘兴诏中国科学院华南植物园中国科学院研究生院

以鼎湖山国家自然保护区季风常绿阔叶林优势种之一木荷的粗死木质残体为研究对象,采用目前国际较认可的腐解等级划分方法,对木荷粗死木质残体3个腐解等级(Ⅰ、Ⅱ、Ⅲ)的密度及养分含量进行测定分析。结果表明:①木荷粗死木质残体的密度... 详细信息

以鼎湖山国家自然保护区季风常绿阔叶林优势种之一木荷的粗死木质残体为研究对象,采用目前国际较认可的腐解等级划分方法,对木荷粗死木质残体3个腐解等级(Ⅰ、Ⅱ、Ⅲ)的密度及养分含量进行测定分析。结果表明:①木荷粗死木质残体的密度随腐解等级的增加从0.58 g/cm3下降到0.16 g/cm3,分解速率常数K值为0.144 7/a,在自然状态下,木荷粗死木质残体分解95%所需时间约为21 a;②粗死木质残体C/N比值随分解的进行先降后升而N/P则相反;③K、Ca、Na、Mg离子浓度随腐解等级的增加出现不同程度的增加,但增幅不明显。研究结果旨在为系统评估粗死木质残体的分解行为在生态系统养分循环中的作用提供基础数据。

关键词：木荷粗死木质残体分解速率养分含量

Configurable integrated maintenance system based on digital production model

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Configurable integrated maintenance system based on digital ...

分子筛改性Co／SiO2催化剂对Fischer-Tropsch合成汽油类烃的影响

2010 chinese Control and Decision Conference

作者： Peng Li~(1,2),Yonggang Sun~3,Haibo Shi~1,Wenli Shang~1 1.Shenyang Institute of Automation,chinese academy of science,Shenyang 110016,china 2.graduate school of chinese academy of science,beijing 100049,china 3.Heilongjiang Tobacco Industry Co.,LTD,Harbin,133001,china

＜正＞To complement the insufficiency of real time and commonality in machine maintenance system,the 95th Standard Project（SP95） standard was adopted for digitized plant *** on the universal digital plant model,a configurable integrated machine maintenance system was built with advanced technology of real-time data collection and mobile ***-Oriented Architecture（SOA） was adopted for the machine maintenance system,and Windows Communication Foundation（WCF） was used to integrate ERP and Inventory System,which provides fluent data flow and information flow for machine maintenance *** key technologies and design of modules related to integrated machine maintenance system were discussed.A practical application in tobacco industry of china was constructed to prove the validity of the integrated machine maintenance system and its theory.

关键词： SP95 standard plant model preventive maintenance condition monitoring

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石油化工 2008年第5期37卷 445-449页

作者：李宇萍王铁军吴创之吕永兴李海滨中国科学院可再生能源与天然气水合物重点实验室

在中孔SiO2中添加USY，HZSM-5，β分子筛组成双功能载体，并采用初湿浸渍法在载体上浸渍钴盐，制备了一系列分子筛改性的Co／SiO2催化剂，考察了分子筛的类型、HZSM-5分子筛的骨架硅铝比、HZSM-5分子筛在载体中的含量对Fischer-Tropsch... 详细信息

在中孔SiO2中添加USY，HZSM-5，β分子筛组成双功能载体，并采用初湿浸渍法在载体上浸渍钴盐，制备了一系列分子筛改性的Co／SiO2催化剂，考察了分子筛的类型、HZSM-5分子筛的骨架硅铝比、HZSM-5分子筛在载体中的含量对Fischer-Tropsch合成汽油类烃（C5-12）的影响。实验结果表明，载体中SiO2和分子筛共同作用，提高了催化剂的活性，并使产物分布向汽油类烃偏移，其中，以HZSM-5分子筛改性的Co／SiO2催化剂的催化性能最好。HZSM-5分子筛改性催化剂对催化性能的影响受其骨架硅铝比的影响。当骨架硅铝比n（SiO2）：n（Al2O3）=38、HZSM-5分子筛在载体中的质量分数为20％时，CO转化率达到80％以上，汽油类烃的选择性高达55％，其中异构烷烃的选择性在10％以上。

关键词： Fischer-Tropsch合成钴/二氧化硅催化剂分子筛汽油类烃

Serum Metabolome is Altered in Arginine-Supplemented Growing Pigs

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Serum Metabolome is Altered in Arginine-Supplemented Growing...

Valuations on arithmetic surfaces

4th International Symposium on Animal Nutrition,Health and Feed Additive

作者： Q.H.He,X.F.Kong,Z.R.Tang,G.Y.Wu,H.R.Tang,P.P.Ren,F.H. Hao,R.L.Huang,T.J.Li,B.E.Tan,Y.N.Wu,and Y.L.Yin 3 Key Laboratory for Agro-ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,The chinese academy of sciences,Changsha,Hunan 410125,P.R.china 4 National Institute for Nutrition and Food Safety,chinese CDC,beijing 100050 china 5 The graduate school of the chinese academy of science,beijing 100049,china 6 Department of Animal science,Texas A&M University,College Station,TX,77843-2471 7 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Centre for Magnetic Resonance,Wuhan Institute of Physics and Mathematics,the chinese academy of sciences,Wuhan,Hubei 430071,china

Arginine plays an important role regulating nutrient metabolism,but the underlying mechanisms are largely *** study was conducted to determine the effect of dietary arginine supplementation on the metabolome in serum of growing pigs using H nuclear magnetic resonance spectroscopy. Sixteen pigs（48±4 kg） were randomly assigned to one of 2 groups,representing supplementation with 0 or 1.0%of L-arginine-HCl to corn- and soybean meal-based *** was collected after 46 d *** arginine supplementation decreased fat deposition and increased protein accretion in the body. Principal component analysis showed that serum concentrations of low-density lipoprotein,very-low-density lipoprotein,and urea were lower,but concentrations of creatinine,tricarboxylic-acid-cycle metabolites,alanine,ornithine,lysine and tyrosine were greater in arginine-supplemented than in control pigs. Additionally,the arginine treatment affected serum concentrations of lipid signalling molecules（glycerophosphorylcholine and myo-inositol） and intestinal bacterial metabolites（formate,ethanol,methylamine, dimethylamine,acetate,and propionate）. These novel findings suggest that dietary arginine supplementation alters the catabolism of fat and amino acids in the whole body, enhances protein synthesis in skeletal muscle, and modulates intestinal microbial metabolism in growing pigs.

关键词： arginine metabolomics serum pigs nuclear magnetic resonance spectroscopy

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science china Mathematics 2009年第1期52卷 66-76页

作者： XU Ning Department of Mathematics, graduate school of chinese academy of sciences, beijing 100049, china Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing 100049 China

In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. Based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n.

关键词： valuation height rank totally ordered group big field transcendental number 14J10

Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese academy of sciences,beijing 100012,china 2 graduate school of chinese academy of sciences,beijing 100049,china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of chinese academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1137 nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12L⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

H_2CO and H110α survey toward UCHII regions

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Research in Astronomy and Astrophysics 2011年第2期11卷 156-162页

作者： Xiao-Hong Han graduate University of chinese academy of sciences, beijing 100049, china National Astronomical Observatories / Urumqi Observatory Chinese Academy of Sciences Urumqi 830011 China graduate University of chinese academy of sciences Beijing 100049 China

We report results of the H2CO and H110α survey toward 281 UCHII regions using the Urumqi 25m radio *** obtained 37 new H2CO detections,and H110α was simultaneously detected in eight of *** H110α was detected in another UCHII *** calculated kinematic distances of nine UCHII regions with the detected H110α and resolved the kinematic distance ambiguity for six of *** detection rate of H2CO of our observation was 13.2%,which is low compared with one of the other *** possible reason is that the sensitivity of our telescope is relatively low.

关键词： ISM: HII regions -- ISM: molecules -- radio lines: ISM

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, beijing 100049 2 graduate school of chinese academy of sciences, beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 and graduate school of chinese academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Applications of URANS on predicting unsteady turbulent separated flows

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Acta Mechanica Sinica 2009年第3期25卷 319-324页

作者： Jinglei Xu Huiyang Ma Department of Physics, graduate University of the chinese academy of sciences, 100049 beijing, china Department of Physics Graduate University of the Chinese Academy of Sciences 100049 Beijing China

Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2D flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS （URANS）. Some typical linear and nonlinear eddy viscosity turbulence models （LEVM and NLEVM） and a quadratic explicit algebraic stress model （EASM） are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding.

关键词： URANS Nonlinear eddy viscosity turbulencemodel ,Separated flows Circular cylinder