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Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2 gas field,Tarim Basin,china

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Science china Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1,3. DONG HailLiang2,3.& RUAN Zhuang1,3.1 State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Beijing 100083. china 2 {3. of Geology, Miami university,Oxford, OH 45056, USA 3.Geomicrobiology Laboratory, china university of Geosciences, Beijing, 100083. china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2 gas field of the Tarim Basin, Northwestern china. Sandstone samples and pore water samples are col-lected from well KL201 in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3.00 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2SO4 type at the shallow depth (3.00-3.3. m), to the NaHCO3.type at the intermediate depth (3.3.―3.95 m),and to the CaCl2 type at the greater depth (3.28―3.3. m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2+ concen-tration, the total inorganic carbon concentration (ΣCO2), and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2] -[Ca2+]). In the Na2SO4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3.water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

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Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science china Chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN Chunyan1, HUANG Yunjie1, LI Jinghong1,2 & CHEN Shaowei3.1. State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 13.022, china 2. department of Chemistry, Tsinghua university, Beijing 100084, china 3. department of Chemistry, university of California, Santa Cruz, Santa Cruz, CA 95064, USA 1. State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences 130022 Changchun China 2. department of Chemistry Tsinghua University 100084 Beijing China 3. department of Chemistry University of California 95064 Santa Cruz Santa Cruz CA USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3.Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

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Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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Science china Chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2, ZHANG Lide1, ZHENG Jiyong2, FU Shangang3.& ZHU Mingwei3.1. Institute of Solid State physics, Chinese Academy of Sciences, Hefei 23.03., china 2. Luoyang Ship Material Research Institute, Luoyang 47103., china 3. College of Life Science, Henan Normal {3., Xinxiang 453.02, china 1. Institute of Solid State physics Chinese Academy of Sciences 230031 Hefei China 2. Luoyang Ship Material Research Institute 471039 Luoyang China 3. College of Life Science Henan Normal University 453002 Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

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A new family of windows——convolution windows and their applications

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Science china(Technological Sciences) 2005年第4期48卷 468-480页

作者： ZHANG Jieqiu1,2, LIANG Changhong1 & CHEN Yanpu3.1. department of Applied Math. & Phys., College of Science, Airforce Engineering university, Xi’an 710051, china 2. National Key Laboratory of Antennas and Microwave Technology, Xidian university, Xi’an 710071, china 3. Computer Center, Xi’an Communication College, Xi’an 710106, china 1. department of Applied Math. & Phys. College of Science Airforce Engineering University 710051 Xi’an China 2. National Key Laboratory of Antennas and Microwave Technology Xidian University 710071 Xi’an China 3. Computer Center Xi’an Communication College 710106 Xi’an China

A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time.

关键词： signal processing harmonic analysis window function convolution window synchronous error spoctral leakage

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COLLECTIVELY COMPACT COMPOSITION OPERATOR SEQUENCES BETWEEN BERGMAN AND HARDY SPACES

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Acta Mathematica Scientia 2004年第2期24卷 206-212页

作者：王茂发刘培德 SchoolofMathematicsandStatistics WuhanUniversityWuhan430072China

This paper studies the collective compactness of composition operator sequences between the Bergman and Hardy spaces. Some sufficient and necessary conditions involving the generalized Nevanlinna counting functions fo... 详细信息

关键词： Bergman space Hardy space composition operator collectively compact operator sequence

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Circadian expression of clock genes and angiotensin Ⅱ type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

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Acta Pharmacologica Sinica 2007年第4期28卷 484-492页

作者： Hui LI~2,Nmg-ling SUN~(2,4),Jin WANG~3.Ai-jun LIU~3.Ding-feng SU~(3.4)~2department of Cardiology,Peking university People's Hospital,Beijing 100044,china ~3.0} of Pharmacology,Second MilitaryMedical university,Shanghai 20043.,china department of Cardiology Peking University People's Hospital Beijing China department of Pharmacology Second Military Medical University Shanghai China

Aim:To investigate whether the circadian expression of central clock genes andangiotensin Ⅱ type 1 (AT1) receptors was altered in sinoaortic-denervated (SAD)***:Male Sprague-Dawley rats underwent sinoaortic denervation or asham operation at the age of 12 *** weeks after the operation,bloodpressure and heart period were measured in the conscious state in a group ofsham-operated (n=10) and SAD rats (n=9).Rest SAD and sham-operated ratswere divided into 6 groups (n=6 in each group).The suprachiasmatic nuclei (SCN)tissues were taken every 4 h throughout the day from each group for the determi-nation of the mRNA expression of clock genes (Per2 and Bmal1) and the AT1receptor by RT-PCR;the protein expression of Per2 and Bmal1 was determined byWestern ***:Blood pressure levels in the SAD rats were similar tothose of the sham-operated ***,blood pressure variabilities signifi-cantly increased in the SAD rats compared with the sham-operated *** variation of clock genes in the SCN of the sham-operated rats was char-acterized by a marked increase in the mRNA and protein expression during ***2 and Bmal1 mRNA levels were significantly lower in the SAD rats,especially during dark *** blot analysis confirmed an attenuation ofthe circadian rhythm of the 2 clock proteins in the SCN of the SAD ***1receptor mRNA expressions in the SCN were abnormally upregulated in the lightphase,changed to a 12-h cycle in the SAD ***:The circadian varia-tion of the 2 central clock genes was attenuated in the SAD *** baroreflexdysfunction also induced a disturbance in the expression of AT1 receptors in theSCN.

关键词： circadian rhythm arterial baroreflex clock genes sinoaortic denervation reninangiotensin system

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Determination of tectonic background for sedimentary basin from sandstone geochemistry

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Chinese Science Bulletin 1998年第14期43卷 1191-1196页

作者： SHAO Lei 1, K. Stattegger 2 and LI Wenhou 3.1. Laboratory of Marine Geology, Tongji university, Shanghai 200092, china 2. Geological and Paleontological Institute, university of Kiel, 24118 Kiel, Germany 3. {3. of Geology, Northwest Unive Laboratory of Marine Geology Tongji University Shanghai China Geological and Paleontological Institute University of Kiel Kiel Germany department of Geology Northwest University Xi’an China

The chemical composition of sedimentary rocks is mainly controlled by source rocks. Through examining chemical composition of terrigenous rocks, the tectonic evolution of a sedimentary basin can be modeled. The Turpan Basin belongs to a continental sedimentary basin and its source rocks are derived from the upper continental crust.

关键词： sedimentary rock geochemistry basin analysis Turpan Basin.

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Effects of astragaloside IV on pathogenesis of metabolic syndrome in vitro

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Acta Pharmacologica Sinica 2006年第2期27卷 229-236页

作者： Ming-en XU~(2,3.4) Shang-zhi XIAO~3.Yong-hong SUN~3.Yang OU-YANG~3.Xiao-xiang ZHENG~(3.4) ~2department of Biomedical Engineering,Hangzhou Dianzi university.Hangzhou 3.0018 ~3.0} of Biomedical Engineering.Zhejiang university.Hangzhou 3.0027.china department of Biomedical Engineering Hangzhou Dianzi UniversityHangzhou 310018 China. xumingen@***

Aim:To investigate the diverse pharmacological actions of astragaloside IV fromthe perspective of metabolic syndrome,and to investigate the effect of the drugon the pathogenesis of metabolic ***:Adipogenesis was usedas an indicator of the effect of astragaloside Ⅳ on preadipocyte differentiation,and was measured by using an oil red O *** uptake was determined bymeasuring the transport of [2-3.]-deoxyglucose into the *** concentrationsof peroxisome proliferator-activated receptor-γ（PPARγ）and aP2 mRNA were de-termined by using reverse transcription-polymerase chain *** viability loss of endothelial cells were detected by using flow cytometry andthe WST-1 assay,*** free Ca2+was labeled with Fluo-3.AMand measured by using a laser scanning confocal ***:Astragaloside Ⅳ can significantly potentiate insulin-induced preadipocyte differ-entiation at concentrations of 3.10,and 3. μg/mL,improve high glucose-inducedinsulin resistance in adipocytes at a concentration of 3. μg/mL,and prevent tumornecrosis factor（TNF）-α-induced apoptosis and viability loss at concentrations of10 and 3. μg/mL,and 3. μg/mL,respectively,in endothelial ***,wefound that these effects were partly due to the promotion of PPARγ expressionand to the inhibition of abnormal TNF-α-induced intracellular free Ca2+accumula-tion in endothelial ***:The diverse pharmacological actions ofastragaloside 1V can all be linked to metabolic syndrome *** studyprovides a new insight into the mechanism by which astragaloside Ⅳ exerts itseffect.

关键词： astragaloside Ⅳ metabolic syndrome X insulin resistance peroxisome proliferatoractivated receptors apoptosis calcium

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Radiation Effect of Neutrons in a Reactor on Polyurethane

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Journal of Wuhan university of Technology(Materials Science) 2010年第6期25卷 966-968页

作者：黄玮 Institute of Nuclear physics and Chemistry China Academy of Engineering Physics

The radiation effect of neutrons in a reactor on polyurethane was *** gases produced by irradiated samples were analyzed by gas chromatography,and the dynamic mechanical and compression properties of the samples were also *** positron annihilation lifetime of irradiated samples was measured at room temperature in *** experimental results indicate that gas chromatography is a powerful tool to quantitatively analyze the gas products from neutron-irradiated polyurethane and characterizes the chemical changes in the *** the changes in microstructure determined from the PAL correlate well with the measurements of the mechanical properties by dynamic mechanical analysis（DMA）.

关键词： neutrons in a reactor polyurethane radiation effect

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A first-principles study of dihydroazulene as a possible optical molecular switch

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Science china(physics,Mechanics & Astronomy) 2011年第3期Mechanics & Astronomy) .卷 437-441页

作者： XIA CaiJuan1, LIU DeSheng2,3.& LIU HanChen1 1 School of Science, Xi’an Polytechnic university, Xi’an 710048, china 2 School of physics, State Key Laboratory of Crystal Materials, Shandong university, Jinan 250100, china 3.department of physics, Jining university, Qufu 273.55, china 1. School of Science Xi’an Polytechnic University Xi’an 710048 China2. School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China3. Department of Physics Jining University Qufu 273155 China

By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of the dihydroazulene optical molecular switch. Three kinds of adsorption sites including the hollow, bridge and top sites are studied. The two forms of this molecule, namely the open form and the closed form, can reversibly switch from each other upon photoexcitation. Their transmission spectra are remarkably distinctive. Theoretical results show that the current of the closed form is always significantly larger than that of the open form for all three adsorption sites, which promises this system as possibly one of the good candidates for optical switches due to its unique advantage, and which may have some potential applications in the future molecular circuit.

关键词： molecular switch nonequilibrium Green’s function electronic transport density functional theory

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