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Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3) Hong-Ning WANG~(2,1*) Xin PAN~4 Tao XIE~1 Qi WU~5 Zi-Wen XIE~1 Wan-Rong ZHOU~1 1 Laboratory of Veterinary and Biotechnology,Sichuan Agricultural university,Ya'an 625014,china 2 Sichuan university Bioengineering Research Center for Animal Disease Prevention and Control,chengdu 610065,china 3 Faculty of Environment and Resource of Dujiangyan Campus,Sichuan Agricultural university,Dujiangyan 611830,china 4 college of earth science,chengd university of technology,chengdu 610059,china 5 college of Life science,Sichuan Agricultural university,Ya'an 625014,china Laboratory of Veterinary and Biotechnology Sichuan Agricultural UniversityYa'an 625014 China Faculty of Environment and Resource of Dujiangyan Campus Sichuan Agricultural UniversityDujiangyan 611830 China Sichuan university Bioengineering Research Center for Animal Disease Prevention and Control Chengdu 610065 China college of earth science Chengdu University of TechnologyChengdu 610059 China college of Life science Sichuan Agricultural UniversityYa'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5 U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5 *** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 51 *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42 *** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris

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Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, china: Implication for ore genesis

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science china earth sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2 & PAN Guitang2 1. Geoscience college, chengdu university of technology, chengdu 610059, china 2. chengdu Institute of Geology and Mineral Resources, chengdu 610082, china Geoscience college Chengdu University of Technology Chengdu China chengdu Institute of Geology and Mineral Resources Chengdu China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, china. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in china. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

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Research on paleo-fluid sources and hydrocarbon preservation conditions in marine carbonates inthe central Yangtze,china

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Petroleum science 2011年第3期8卷 239-250页

作者： Wang Guozhi Xu Guosheng Yuan Haifeng Hu Xiaofeng Zou Can State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Chengdu 610059 China School of earth science Chengdu University of Technology Chengdu 610059 China Research Institute of Petroleum Exploration and Development Jianghan Oilfield Company SINOPEC Qianjiang Hubei 433124 China college of Foreign Languages ＆ Cultures Chengdu University of Technology Chengdu 610059 China

^87Sr/^86Sr, δ^18O and δ^13C ratios of calcite, dolomite, gypsum filling vugs and fissures in marine carbonates and their host rocks from the Sinian to the middle Triassic, are employed to trace the possible source and migration path of key fluids related to development of hydrocarbon, hydrocarbon preservation condition are then discussed further. Comprehensive research, based on the paleo-fluid, the property of formation water and the deformation intensity etc., indicates that the preservation conditions in the Shizhu synclinorium zone and Fangdoushan anticlinorium zone are the most predominant in the central Yangtze. Three sets of fluid systems in the Shizhu synclinorium zone are identified. Little fluid exchange occurs between the upper-middle fluid system and the lower fluid system, so two independent preservation units have developed. Both the Permian and the Triassic in the upper preservation units and the Dengying Formation of the Sinian and the lower Cambrian in the lower preservation units have good preservation conditions. The preservation condition in the lower association （Z-S） located in the Huaguoping synclinorium zone in the western Hubei and Hunan is better than that in other tectonic units, where the fluids in the lower association migrated vertically across strata when the fluid isolating intervals were destroyed, the regional seals are absent and the conditions for the preservation of hydrocarbon accumulations are totally destroyed. The preservation condition is increasingly more favorable from the western Jiangxi and Hunan to the western Hubei ＆ eastern Chongqing on the whole.

关键词： The central Yangtze marine carbonate fluid, ^87Sr/^86Sr geochemistry trace preservation condition

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Density functional theory study of the magnetic properties of rare earth complexes:the magnetic coupling mechanism in Y~Ⅲ and Gd~Ⅲ complexes with nitronyl nitroxide

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science china Chemistry 2009年第11期52卷 1961-1968页

作者： REN Jie1,2,WANG BingWu1 & CHEN ZhiDa1 1 Beijing National Laboratory for Molecular sciences,State Key Laboratory of Rare earth Materials Chemistry and Applications,college of Chemistry and Molecular Engineering,Peking university,Beijing 100871,china 2 college of science,Hebei university of science and technology,Shijiazhuang 050018,china Beijing National Laboratory for Molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing China college of science Hebei University of Science and Technology Shijiazhuang China

The magnetic coupling interactions of the nitronyl nitroxide radicals bound to diamagnetic(YⅢ) and paramagnetic(GdⅢ) rare earth ions in two model magnetic systems based on novel rare earth organic radical complexes Ln(hfac)3(NITPhOCH3)2(Ln=YⅢ 1,GdⅢ 2;hafc = hexafluoroacetylacetonate;NIT-PhOCH3 = 4'-methoxyo-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been investigated by density functional theory(DFT).The magnetic coupling mechanisms were also explored from the viewpoint of molecular orbital and spin density *** calculations show that the empty 4d-orbitals of YⅢ and 5d-orbitals of GdⅢ play an important role in the antiferromagnetic coupling between the two nitronyl nitroxide radical ligands,and that the ferromagnetic coupling between the GdⅢ ion and the radical magnetic centers can be attributed to the nearly complete localization of the isotropic 4f-shell and singly occupied magnetic orbital(π) of the nitronyl nitroxide.

关键词： magnetic coupling density functional theory rare earth ion gadolinium(Ⅲ) complexes yttrium(Ⅲ) complexes

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Distribution and Elimination of Lead Species in Soils Related to GAP of Chinese Medicinal Materials of Ligusticum Chuanxiong Hort

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地球科学进展 2004年第S1期19卷 419-423页

作者： DENG Tian-long~(1,2),JIA Min-ru~2,LIAO Meng-xia~1 (1. college of Materials and Bioengineering, chengdu university of technology, chengdu 610059, china 2. college of Pharmacology, chengdu university of Traditional Chinese Medicine, chengdu 610059 ,china)

In this paper, the sequential extraction procedure was used for the selection of fractions of lead in seven stages corresponding to lead exchangeable, lead bounded to carbonates, to manganese oxides, to organic matters, to amorphous iron, and lead associated to crystallized iron, and to residuals. The vertical distributions of lead species were carried out in the soils related to good agriculture progress (GAP) of Chinese medical materials of Ligusticum chuanxiong Hort in Dujiangyan city and Wenchuan Co...

关键词： Chinese medical Materials Phytoremediation Soils Lead speciation

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New research progress on the ultrastructure of tectonically deformed coals

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Progress in Natural science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,Xiaoshi Li Laboratory of Computational Geodynamics,college of earth science,Graduate university of Chinese Academy of sciences,Beijing 100049,china Laboratory of Computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within china and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3) the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： Tectonically deformed coals Ultrastructure Pore structure Tectonic stress Strain environment

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Inclination Deepening of Paleogene Red Beds in the Qiangtang Terrane,the Hinterland of the Qinghai-Tibet Plateau

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地学前缘 2009年第S1期16卷 94-95页

作者： Bo Ran,Zhifei Liu,Chengshan Wang,Xixi Zhao,Yalin Li 1.college of earth sciences,chengdu university of technology,chengdu 610059,china. 2.Laboratory of Marine Geology,Tongji university,Shanghai 200092,china 3.State Key Laboratory of Geological Processes and Mineral Resources,Research Center for Tibetan Plateau Geology,china university of Geosciences,Beijing 100083,china 4.Institute of Tectonics and earth sciences Department,university of California,Santa Cruz,CA 95064,USA

In this research,one hundred and ten samples（ten sampling localities）were drilled by a portable petrol-driven drill in the Tongtianhe area along the highway where developes Yaxicuo Group,Oligocene. Complete demagnetization were finished in university of California,Santa Cruz（UCSC）.These remanence data were collected:Dg=334.2,Ig=52.3,α95=7.1,k=7.3（before structural correction）;Ds=27.2, Is=66.6,α95=7.3,k=7.0（after structural correction）.

关键词： inclination deepening red beds Yaxicuo Group remagnetization

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A Kinematic Thermal Model for Descending Slabs with Velocity Boundary Layers

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地学前缘 2009年第S1期16卷 195-196页

作者： Keliang Zhang Graduate university of the Chinese Academy of sciences,college of earth science,Beijing 100049,china.

Kinematic models compute the temperature distribution by prescribing a constant convergent velocity for the subducting slab,resulting in an artificial velocity discontinuity,which may accelerate the heating of subducting *** the purpose to moderate the influence of such artificial discontinuity, we construct a 2D thermal model for subduction zones with a velocity boundary layer,within which the velocities decrease linearly with the distance from the interfaces of *** are calculated

关键词： kinematic model thermal structure subduction zone velocity boundary layer finite element method

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Chromo-chemodosimetric detection for Fe^(2+) by Fenton reagent-induced chromophore-decolorizing of halogenated phenolsulfonphthalein derivatives

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science china Chemistry 2010年第6期53卷 1398-1405页

作者： ZHENG Kuan,LAI ChengYue,HE LiPing & LI Fang Key Laboratory of Green Chemistry and technology,Ministry of Education college of Chemistry,Sichuan university,chengdu 610064,china Key Laboratory of Green Chemistry and technology Ministry of Education College of Chemistry Sichuan University Chengdu China

A commercially-available sulfonphthalein derivative was demonstrated to be a chemodosimeter for Fe2+ and its sensing behavior was further investigated by UV-vis spectroscopy in aqueous media under the optimum *** the presence of chlorophenol red (CPR) and H2O2,the absorption maximum at 435 nm decreased upon addition of Fe2+,resulting in a significant color change of the CPR solution from yellow to *** chemosensor system did not show significant responses to a series of other metal ions including Al3+,Zn2+,Cd2+,Hg2+,Mn2+,Co2+,Fe3+,Ni2+,Cu2+,La3+,Ce4+,Th4+,Pd2+,Pb2+,Sb3+,Cr3+,Au3+,Ag+,Nd3+,Sm3+,alkali and alkaline earth metal cations,allowing for highly selective naked-eye detection of Fe2+.Quantitative analysis was carried out kinetically for practicable the Fe2+ assay when either fixed time method or the initial rate method was *** the detecting time was set,the decrease of absorbance signal was linear with Fe2+ concentration in the range of 0 to 7.50 × 10-5 mol L-1 and the regression equation was ΔA = 0.00759 + 0.00593CFe with a correlation coefficient r = *** chemodosimetric system has employed an irreversible Fenton reagent-promoted oxidation of the CPR free chromophore and the hydroxyl radicals were generated in the presence of both Fe2+ and hydrogen *** mechanistic interpretation of the signaling process was partially confirmed by the radical scavenging experiment and the FT-IR analysis of the intermediates formed at different reaction periods.

关键词： colorimetric chemosensor ferrous ion sulfonphthalein Fenton reagent

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The gravitational gradient tensor’s invariants and the related boundary conditions

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science china earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3 & ZHAO DongMing4 1 college of earth science, Graduate university of Chinese Academy of sciences, Beijing 100049, china 2 Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 430077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 710043, china 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052, china college of earth science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China Zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the earth’s gravitational field gravitational gravidiometry tensor’s invariant

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