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Effect on the Performance of Drilling Fluids at Downhole Rock Surfaces at Low Temperatures

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Journal of Earth Science 2016年第5期27卷 856-863页

作者： Mingming Zheng Guosheng Jiang Tianle Liu Fulong ning ling Zhang V.F.Chikhotkin Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring (Central South University) Ministry of Education Engineering faculty China university of Geosciences Key Lab of Drilling and Exploitation Technology in Complex Conditions Jilin University

To maintain gas hydrate stability, low-temperature drilling fluids and high drilling speeds should be used while drilling in gas hydrate-bearing sediments. The effect of the drilling fluid on downhole rock surfaces at low temperatures is very important to increase the drilling rate. This paper analyzed the action mechanism of the drilling fluid on downhole rock surfaces and established a corresponding evaluation method. The softening effect of six simulated drilling fluids with 0.1 wt.% of four common surfactants and two common organic salts on the downhole rock surface strength was evaluated experimentally using the established method at low temperature. The experimental results showed that the surfactants and organic salts used in the drilling fluids aided in the reduction of the strength of the downhole rock surface, and the established evaluation method was able to quantitatively reveal the difference in the softening effect of the different drilling fluids through comparison with water. In particular, the most common surfactant that is used in drilling fluids, sodium dodecyl sulfate（SDS）, had a very good softening effect while drilling under low-temperature conditions, which can be widely applied during drilling in low-temperature formations, such as natural gas hydrate-bearing sediments, the deep seafloor and permafrost.

关键词： gas hydrate bearing sediments low temperature drilling fluid performances downholerock surface strength influence mechanism.

In(OTf)_3 catalyzed allylation reaction of imines with tetraallyltin

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Chinese Chemical Letters 2009年第1期20卷 40-43页

作者： Xiao ning Wei ling Yan Liu Bing Wang Wei Xing Chang Jing Li The State Key Laboratory Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tanjin 300071 China

In the presence of catalytic amount of In（OTf）3 （10 mol%）, a series of aldimines reacted with tetraallyltin in a 2：1 molar ratio to afford the corresponding homoallylic amines in good yields. The good atom efficiency was achieved under mild reaction conditions and a new protocol （allyl）4Sn/In（OTf）3 for simple imines was developed.

关键词： Catalytic allylation Aldimine Tetraallyltin In(OTf)3

Habitat-specific changes of plant and soil microbial community composition in response to fairy ring fungus Agaricus xanthodermus on the Qinghai-Tibet Plateau

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Soil Ecology Letters 2024年第3期6卷 189-197页

作者： Juan Du Cong He Fuxin Wang ning ling Shengjing Jiang State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China College of Ecology Lanzhou UniversityLanzhou 730000China

Fairy rings are common in diverse global biomes and often appear as lush vegetation in one to three concentric zones caused by the spread of mycelia in grassland ***,the underlying mechanisms and environmental adaptation of fairy rings remain largely *** this study,two fairy rings(A and B)caused by Agaricus xanthodermus were sampled on the Qinghai-Tibet Plateau during a time when fairy rings are most *** conducting a vegetation survey and high-throughput sequencing,the changes of plants and soil microorganisms to fairy ring fungi were *** above-ground biomass at both fairy rings was greatly increased by fairy ring fungi,but the response of dominant plant species is different at two fairy ring *** addition,bacterial and fungal communities significantly varied within distinct sampling zones across the fairy rings,and showed variable genus-specific responses at two fairy ring *** fairy ring A,soil available N:P ratio was essential in shaping the structure of plant and microbial community,while soil available N concentration was the most important predictor at fairy ring *** together,our results indicated Agaricus xanthodermus fairy rings have variable effects on alpine meadow plants and soil microbes at different *** propose that the impacts of fairy ring fungi on plants and microbes are determined by the level of soil available N concentration and available N:P *** results contribute to a better understanding of the mechanisms through which fairy rings affect the vegetation of alpine meadows.

关键词： Fairy rings alpine meadow soil microbes plant-soil relationships

Inhibitory effects of amiodarone on simvastatin metabolism in human liver microsomes

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Journal of Geriatric Cardiology 2009年第2期6卷 115-118页

作者： Chao Wan Jiang wei Zhang ning Zhu ling Yang Medical Department No 2 Clinical Department No. 403 Hospital No. 210 of PLA Dalian Liaoning 116021 China

Objective To investigate the effects ofamiodarone （AMD） on simvastatin （SV） in human liver microsomes and the possible underlying mechanisms. Methods Time-, NADPH- and concentration-dependent inhibitions were tested in HLM. The logarithm of relative inhibition values was plotted versus preincubation time （0, 5, 10, 15, 20min） for a series concentration of AMD used （0, 2, 5, 25, 50 umol/L）, and the slopes determined by linear regression. These slope values represente the observed inactivation rate constants （kobs ）. A double-reciprocal plot was then constructed using the reciprocal of the kobs （y-axis） and the reciprocal of the associated inhibitor concentration （x-axis） to estimate the values of kinact and K1, which were two principal kinetic constants that were specific for mechanism-based inhibition （MBI）.drug-drug interactions （DDI） potential was predicted based on in vitro data and by using the in vitro-in vivo extrapolation. Results The time-, concentration- and NADPH-dependent characteristics confirmed that when SV was the substrate of CYP3A4, the inhibition of AMD to CYP3A4 is MBI. KI and kinact value were calculated to be 5.1umol/L and 0.018minL The CLant of SV was reduced 2.96-5.63 fold when it was administrated with AMD. Conclusion Based on the results, AMD would inhibit SV metabolism via the mechanism-based manner, which would lead to DDI when they are taken together. Careful clinical observation is recommended when AMD and SV have to be simultaneously prescribed.

关键词： amiodarone simvastatin CYP3A4 drug-drug interaction mechanism-based inhibition

Solvothermal Synthesis and Characterization of (NH_3CH_2CH_2NH_3)HgSnS_4 with a Column Structure

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Chemical Research in Chinese Universities 2006年第4期22卷 411-414页

作者： WANG Yan-yan BAIYIN Meng-he JI Shou-hua LIU Xiao-yang AN Yong-lin ning Gui-ling Department of Chemistry Dalian University of TechnologyDalian 116024 P. R. China Department of Materials Dalian University of TechnologyDalian 116024 P. R. China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130023 P. R. China

A compound （NH3 CH2 CH2 NH3 ）HgSnS4 with a column structure was synthesized solvothermally and characterized by X-ray single-crystal diffraction. This compound crystallizes in the monoclinic space group C2/c with a = 1. 3863 （6） nm, b = 0. 6640 （ 3 ） nm, c = 2. 3198 （10） nm, β = 106. 168 （ 7 ）° and Z = 8. It consists of anionic columns of [ HgSnS4 ]^2- that are interrupted by cationic columns of [ EnH2 ]^2＋ . Its thermal and optical properties were studied.

关键词： Solvothermal synthesis Quaternary thiostannate Crystal structure

Construction of Ionic Porous Organic Polymers(iPOPs)via Pyrylium Mediated Transformation

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Chinese Journal of Polymer Science 2020年第9期38卷 958-964,I0006页

作者： Shi-Yue Zhang Wei-Tao Gong Wei-Dong Qu Xiao-Rong Deng Kai-Xun Dong Shu-Guang Zhang Gui-ling ning State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China Engineering Laboratory of Boric and Magnesic Functional Material Preparative and Applied Technology Dalian 116024China

Two new ionic porous organic polymers(iPOPs)with different counter anions were successfully fabricated via well-known pyrylium mediated transformation into pyridinium.13C solid-state NMR,XPS,and FTIR were analyzed and confirmed the formation of pyridinium in the *** charged and aromatic networks,both iPOPs exhibit a high affinity towards toxic hexavalent chromium Cr(Ⅵ)*** is more,it has been demonstrated that both CO2 adsorption and Cr(Ⅵ)removal properties can be tuned by simply varying counter anions.

关键词： Ionic porous organic polymers Pyrylium CO2 adsorption Hexavalent chromium removal Different counter anions

Synthesis of micrometer SrAl_2Si_2O_8:Eu,Dy blue phosphor powders via sol-gel process

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功能材料与器件学报 2008年第1期14卷 197-200页

作者： PAN Wen ning Gui-ling LIN Yuan WANG Jing State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China

In this paper,we report on long-persistence white phosphor SrAl2Si2O8:Eu2+,Dy3+ synthesized by the sol-gel *** luminescent materials prepared by the sol-gel method have many advantages,such as uniform composition,high purity,fine grains and low synthesis *** found that SrAl2Si2O8:Eu2+,Dy3+ phosphor prepared by the sol-gel method can provide more luminescent intensity and better afterglow characteristic compared with the same phosphor prepared by solid-state ***,the particle size and shape of phosphors should be optimized to obtain the maximum quantum efficiency through energy *** microstructure of the phosphor consisted of regular fine grains with an average size of about 0.5-1 μ*** 356 nm light excitation,the broadband emission of the phosphor continues from 350 to 650 nm and the emission peak is at about 414 nm,which can be viewed as the typical emission of Eu2+ ascribed to the 4f→5d transitions.

关键词：蓝色磷光粉凝胶-溶胶法合成发光特性铕镝铝硅酸锶

Endogenous hydrogen sulfide and ERK1/2-STAT3 signaling pathway may participate in the association between homocysteine and hypertension

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Journal of Geriatric Cardiology 2019年第11期16卷 822-834页

作者： Lin SHI Xiao-Yun LIU Zhi-Gang HUANG Zhi-Yi MA Yang XI Lu-Yan WANG ning-ling SUN Hypertension Research Laboratory Department of CardiologyPeking University People’s HospitalBeijingChina Emergency Department Peking University Shenzhen HospitalShenzhenChina

Background Homocysteine(Hcy)is a risk factor for hypertension,although the mechanisms are poorly *** We first explored the relationship between Hcy levels and blood pressure(BP)by analyzing the clinical data of primary hypertensive patients admitted to our ***,we explored a rat model to study the effect of Hcy on blood pressure and the role of *** hyperhomocysteinemia(HHcy)rat model was induced to explore the effect of Hcy on blood pressure and the possible *** carried out tissue histology,extraction and examination of RNA and ***,we conducted cell experiments to determine a likely mechanism through renin-angiotensin-aldosterone system(RAAS)and extracellular signal-regulated kinase 1/2(ERK1/2)signaling *** In primary hypertensive inpatients with HHcy,blood pressure was significantly higher as compared with inpatient counterparts lacking *** the rat model,blood pressure of the Wistar rats was significantly increased with increases in serum Hcy levels and decreased after folate *** converting enzyme 1(ACE1)expression in the Wistar Hcy group was enhanced comparing to controls,but was decreased in the Wistar folate *** II receptor type 1(AGTR1)levels in the kidney tissue increased in the Wistar folate *** serum H2S and kidney cystathionineγ-lyase decreased with elevated levels of serum *** vitro,increased concentrations and treatment times for Hcy were associated with increased expression of collagen type 1 and *** dose and time dependent response was also observed for p-STAT3 and p-ERK1/2 *** Endogenous H2S might mediate the process of altered blood pressure in response to changes in serum Hcy levels,in a process that is partly dependent on activated RAAS and ERK1/2-STAT3 signaling pathway.

关键词： Angiotensin converting enzyme 1 Blood pressure ERK1/2-STAT3 signaling pathway Homocysteine Hydrogen sulfide

Regulation of intracellular Ca2+and calcineurin by NO/PKG in proliferation of vascular smooth muscle cells

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Acta Pharmacologica Sinica 2005年第3期26卷 323-328页

作者： Shi-jun LI ning-ling SUN~1 Department of Cardiology,People’s Hospital,Peking University,Beijing 100044,China Department of Cardiology People's Hospital Peking University Beijing China

Aim:To determine whether Ca2+/calcineurin mediated the inhibitory effects ofnitric oxide/cGMP-dependent protein kinase (NO/PKG) on the proliferation ofvascular smooth muscle cells (VSMC).Methods:Proliferation and viability ofprimary VSMC from rat aorta were measured using [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay and acridine orange and ethidiumbromide staining,*** Ca2+was determined by Fluo-3/*** protein and its activity were assayed using immunoblotting and freeinorganic phosphate analysis,***:(e)-S-nitroso-N-acetyl-penicillamine (SNAP) and Sp-8-(4-chlorophenylthio)-guanosine-3′,5′-cyclicmonophosphorothioate (Sp-8-pCPT-cGMPS) decreased phenylephrine (PE)-in-duced proliferation of VSMC by 27.3% and 36.6%,respectively,but Rp-8-[(4-chlorophenyl)thio]-guanosine-3′,5′-cyclic monophosphorothioate (Rp-8-pCPT-cGMPS) increased PE-induced proliferation of ***,Sp-8-pCPT-cGMPS,and Rp-8-pCPT-cGMPS did not affect the viability of *** proteinwas decreased by 63.1% and its activity was decreased by 59.7% in smooth musclecells (SMC) pretreated with verapamil (Ver) and then stimulated by *** SMCpretreated with Vet,the absorbance of cells stimulated by PE decreased by 22.0%and was further inhibited by the additional treatment of SNAP and *** SMC pretreated with cyclosporin A (CsA),the absorbance of cellsstimulated by PE decreased by 36.7%,but could not be further altered by theadditional treatment of SNAP,Sp-8-pCPT-cGMPS,and ***,Ver inhibited PE-induced intracellular Ca2+variations,which could befurther inhibited by SNAP and Sp-8-pCPT-cGMPS,but not by ***,the increase in calcineurin activity induced by PE was inhibited bySNAP and Sp-8-pCPT-cGMPS,but was promoted by ***:NO/PKG regulates calcineurin activity via the modulation of intracel-lular Ca2+concentration,and thus partially inhibits the prolifera

关键词： calcium calcineurin nitric oxide cGMP-dependent protein kinase vascular smooth muscle