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The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3.and Xin-Wu Cao1,2 1 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 20003.,{3. 2 Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, Shanghai 20003.,{3. 3.graduate school of the chinese academy of sciences, Beijing 10004.,{3. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate school of the chinese {3. of {4. Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 14. blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

MicroRNA (miR3.6) negatively regulates expression of ceramidase-like genes in Arabidopsis

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Progress in Natural Science:Materials International 2009年第6期19卷 781-785页

作者： Dongmei Liu a,b, Diqiu Yu a, a Xishuangbanna Tropical Botanical Garden, chinese academy of sciences, Kunming 650223.{3. b {4. school of the chinese academy of sciences, Beijing 10004.,{3. [a]Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China [b]Graduate School of the Chinese Academy of Sciences Beijing 100049 China

MicroRNAs (miRNAs) are 21-23.nucleotide (nt), endogenous RNAs that regulate gene expression by targeting mRNAs for direct cleavage or translational repression in plants. In Arabidopsis, miR3.6 is encoded by two different loci (MIR3.6a and MIR3.6b) and sequence analysis suggests it may target three ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2 and Atceramidase-like 3.. To demonstrate the biological function of miR3.6, we inserted the synthetic precursors, MIR3.6a or MIR3.6b, under the control of the enhanced cauliflower mosaic virus (CaMV) 3.S promoter, into a plant transformation vector (pOCA3.) and transformed the constructs into Arabidopsis. The promoter increased miR3.6 levels by more than 2-fold, indicating appropriate maturation of the synthetic precursor MIR3.6a or MIR3.6b transcript in transgenic plants. Microarray analysis showed that the transcript levels of two ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2) were decreased by more than 2-fold and lactosylceramide 4.a-galactosyltransferase increased by more than 2-fold in transgenic plants compared with the empty vector-transformed plants. Northern blot analysis showed that the mRNA levels of the two ceramidase-like genes were significantly reduced in transgenic plants. These results indicated that miR3.6 probably plays a crucial role in the ceramide metabolism pathway by negatively regulating the expression of ceramidase-like genes in Arabidopsis.

关键词： miR3.6 miR3.6 precursor Ceramidase Ceramide

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, chinese academy of sciences, Shanghai 201800,{3. 2. {4. school of chinese academy of sciences, Beijing 10003.,{3. 3. Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093.{3. 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. graduate school of chinese {3. of {4. 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 1100°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 196 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.

Positive Charges on Lysine Residues of the Extrinsic 18 kDa Protein Are Important to Its Electrostatic Interaction with Spinach Photosystem Ⅱ Membranes

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Acta Biochimica et Biophysica Sinica 2005年第11期37卷 737-742页

作者： Jin-Peng GAO Zhen-Hua YONG Feng ZHANG Kang-Cheng RUAN Chun-He XU Gen-Yun CHEN Institute of Plant Physiology & Ecology.Shanghai Institutes for Biological sciences,chinese academy of sciences,Shanghai 20003.,{4. Laboratory of Proteomics,Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological sciences,chinese academy of sciences,Shanghai 20003.,{4. College of sciences,Zhejiang University.Hangzhou 3.0029,{4. graduate {13. of the chinese academy of sciences,Shanghai 20003.,{4. Institute of Plant Physiology & Ecology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200032 China graduate school of the chinese {3. of {4.Shanghai 20003. China College of sciences Zhejiang UniversityHangzhou 310029 China Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China

To determine the contribution of charged amino acids to binding with the photosystem Ⅱcomplex(PSⅡ),the amino or carboxyl groups of the extrinsic 18 kDa protein were modified with N-succinimidyl propionate(NSP)or glycine methyl ester(GME)in the presence of a water-soluble carbodiimide,*** on isoelectric point shift,4.10 and 10-14.amino groups were modified in the presence of2 and 4.mM NSP,***,3.4.carboxyl groups were modified by reaction with *** of negatively charged carboxyl groups with GME did not alter the binding activity of theextrinsic 18 kDa ***,the NSP-modified 18 kDa protein,in which the positively charged aminogroups had been modified to uncharged methyl esters,failed to bind with the PSⅡ membrane in the presenceof the extrinsic 23.kDa *** defect can not be attributed to structural or conformational alterationsimposed by chemical modification,as the fluorescence and circular dichroism spectra among native,GME-and NSP-modified extrinsic 18 kDa proteins were ***,we have concluded that the positive chargesof lysyl residues in the extrinsic 18 kDa protein are important for its interaction with PSⅡ membranes in thepresence of the extrinsic 23.kDa ***,it was found that the negative charges of carboxylgroups of this protein did not participate in binding with the extrinsic 23.kDa protein associated with PSⅡmembranes.

关键词： extrinsic 18 kDa protein circular dichroism electrostatic interaction chemical modification

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3., HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4., ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of {3., Beijing 100012, china 2 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of {3., Beijing 10004., china 3.graduate University of the chinese academy of {3., Beijing 10004., china 4.Department of Physics, Nanjing Normal University, Nanjing 210011, china 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

A formula on linear complexity of highest coordinate sequences from maximal periodic sequences over Galois rings

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Progress in Natural Science:Materials International 2006年第9期16卷 998-1001页

作者： HU Lei and SUN Nigang (State Key Laboratory of Information Security, graduate school of chinese {3. of {4., Beijing 10004., china) [a]State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing China

Using a polynomial expression of the highest coordinate map, we deduce an exact formula on the linear complexity of the highest coordinate sequence derived from a maximal periodic sequence over an arbitrary Galois ring of characteristic p2 , where p is a prime. This generalizes the known result of Udaya and Siddiqi for the case that the Galois ring is Z4.

关键词： Galois ring highest coordinate sequence linear complexity.

Phylogeny of fireflies (Coleoptera: Lampyridae) inferred from mitochondrial 16S ribosomal DNA, with references to morphological and ethological traits

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Progress in Natural Science:Materials International 2006年第8期16卷 817-826页

作者： LI Xueyan, YANG Shuang, XIE Meng and LIANG Xingcai (Laboratory of Entomology, Kunming Institute of Zoology, chinese academy of sciences, Kunming 650223.{3. Key Laboratory of Cellular and Molecular Evolution, Kunming Institute of Zoology, chinese academy of sciences, Kunming 650223.{3. graduate school of the chinese academy of sciences, Beijing {13.,{3.) [a]Laboratory of Entomology Kunming Institute of Zoology Chinese Academy of Sciences Kunming China [b]graduate school of the chinese {3. of {4. Beijing China [c]Key Laboratory of Cellular and Molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming China

We sequenced partial mitochondrial 16S ribosomal DNA (16S rDNA) of 18 firefly species from Southwest of china. Combined with homologous sequences previously reported, phylogenetic trees including Japanese, Korean and chinese species were reconstructed by neighbor-joining, maximum parsimony and Bayesian methods. All reconstructions agree on most nodes of the trees. Monophyly of Lampyridae is not supported because Rhagophthalmus ohbai in Rhagophthalmidae is included within it. Lamprigera, a genus placed unreliably in Lampyrinae, shows a close relationship to Amydetinae. Monophyly of Luciolinae is not supported because Pristolycus sagulatus (Lampyrinae) is included within it. In the Luciolinae, monophyly of Curtos and Hotaria is well established, respectively, but both morphological and molecular data continue to indicate that Luciola is not monophyletic and its subdivision is indeed necessary. Within the Lampyrinae, both Pyrocoelia and Diaphanes are not monophyletic, but monophyly of Pyrocoelia + Diaphanes is well supported. Phylogeny of Diaphanes is discussed for the first time. Generic placement of a newly discovered species (Diaphanes pectinealis Li et Liang) sharing some characters of Pyrocoelia and Diaphanes challenges the delimitation of these two similar genera. With references to the firefly mating systems, we suggest that more emphases should be placed on those sexually selected characters such as antennal structure in taxonomy of Lampyridae.

关键词： Lampyridae mitochondrial 16S rDNA morphological and ethological traits phylogeny.

The deep thermal characteristic of continental margin of the northern South china Sea

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chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. graduate school, University of Science and Technology of china, {3. {4. of sciences, Beijing 10003., china 2. Institute of Geology, {3. {4. of sciences, Beijing 100029, china graduate school University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 3.% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

Preparation of Pt/K_2La_2Ti_3._(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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Science china Chemistry 2006年第2期49卷 162-168页

作者： CUI Wenquan1,3. LIU Li2, FENG Liangrong1, XU Chenghua1, LI Zijian1, Lü Shaojie1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese academy of sciences, Chengdu 6100{3., china 2. Chemistry Department, Sichuan University of Science & Engineering, Zigong 6{3.03., china 3. graduate school of the chinese academy of sciences, Beijing 10003., china Correspondence should be addressed to Qiu Fali 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China 3. graduate school of the chinese {3. of {4. Beijing 100039 China 2. Chemistry Department Sichuan University of Science & Engineering Zigong 643033 China

A layered perovskite-type oxide K2La2Ti3.10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2La2Ti3.10 as a co-catalyst with different methods. The dispersion of platinum on K2La2Ti3.10 was determined with HOT method. The photocatalytic activity of Pt/K2La2Ti3.10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2La2Ti3.10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 23..88 μmol·h?1 by Pt(2%)/K2La2Ti3.10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2La_2Ti_3._(10) support