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A thermodynamic hypothesis regarding optimality principles for flow processes in geosystems

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Chinese Science Bulletin 2014年第16期59卷 1880-1884页

作者： Hui-hai Liu Earth Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

This paper proposes a new thermodynamic hypothesis that states that a nonlinear natural system that is not isolated and involves positive feedbacks tends to minimize its resistance to the flow process through it that is imposed by its *** demonstrate that the hypothesis is consistent with flow behavior in saturated and unsaturated porous media,river basins,and the Earthatmosphere *** optimization for flow processes has been previously discussed by a number of researchers in the literature,the unique contribution of this work is to indicate that only the driving process is subject to optimality when multiple flow processes are simultaneously involved in a system.

关键词：地球系统流动过程热力学假说饱和多孔介质自然系统江河流域流动行为

Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations

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Petroleum Science 2024年第4期21卷 2779-2792页

作者： Si-Qi yang Jian-Chun Fan Ming-tao Liu De-Ning Li Jun-Liang Li Li-Hong Han Jian-Jun Wang Shang-Yu yang Si-Wei Dai Lai-Bin Zhang State Key Laboratory of Oil and Gas Equipment CNPC Tubular Goods Research InstituteXi'an710077ShaanxiChina Key Laboratory of Oil and Gas Safety and Emergency Technology China University of PetroleumBeijing102249China Oil Production Technology Research Institute of Liaohe Oilfield Company Panjin124010LiaoningChina Tianjin Gas Storage Branch PetroChina Dagang Oilfield CompanyTianjin300280China Petroleum Production Engineering Research Institute Daqing Oilfield CompanyDaqing163712HeilongjiangChina

Erosion wear is a common failure mode in the oil and gas *** the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed solid particles in the fracturing *** such complex conditions,the vulnerable components of the pipe system are prone to perforation or even burst accidents,which has become one of the most serious risks at the fracturing ***,it is not yet fully understood the erosion mechanism of pipe steel for hydraulic ***,this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical ***,we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the *** effects of impact angle,flow velocity and applied stress on erosion wear were comprehensively *** a particle impact dynamic model of erosion wear was developed based on the experimental parameters,and the evolution process of particle erosion under different impact angles,impact velocities and applied stress was *** combining the erosion characteristics,the micro-structure of the eroded area,and the micro-mechanics of erosion damage,the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first *** high-pressure operating conditions,it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased,resulting in more severe erosion wear of fracturing pipes.

关键词： Erosion wear Applied stress Particle impact dynamics Erosion mechanism

Synthesis and Crystal Structure of a Heterotrinuclear Compound [PdCu_2(tdt)(μ-dppm)_2(MeCN)_4]-(ClO_4)_2·2/3H_2O (tdt = 3,4-Toluenedithiolate, dppm =Bis(diphenylphosphino)methane)

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Chinese Journal of Structural Chemistry 2005年第6期24卷 621-624页

作者： QLNYong-hai WUMei-Mei CHENZhong-Ning StateKeyLaboratoryofStructuralChemistry，FujianInstituteofResearchontheStructureofMatter TheChineseAcademyofSciencesFuzhouFujian350002China

The heterotrinuclear compound [PdCu2(tdt)(μ-dppm)2(MeCN)4](ClO4)2?2/3H2O 1 (tdt = 3,4-toluenedithiolate, dppm = bis(diphenylphosphino)methane) has been prepared and characterized by X-ray structural analysis. Compound 1 crystallizes in trigonal system, space group R3c with a = b = 34.4275(3), c = 32.6700(5) ?, V = 33534.4(7) ?3, Mr = 1527.21, Z = 18, Dc = 1.361 g/cm3, F(000) = 13974, μ(MoKα) = 1.069 mm-1, the final R = 0.0703 and wR = 0.1389 for 8375 observed reflections with I>2σ(I). The dithiolate tdt displays a chelating and bridging coordination mode, which chelates a PdII and bridges two Cu? atoms. The PdII center is located in an approximate square-planar environment with S2P2 donors, and each Cu? center exhibits a tetrahedral geometry.

关键词： copper crystal structure dppm palladium 3,4-toluenedithiolate

Photolysis of chlortetracycline in aqueous solution:Kinetics,toxicity and products

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Journal of Environmental Sciences 2012年第2期24卷 254-260页

作者： Yong Chen Hua Li Zongping Wang tao tao Dongbin Wei Chun Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of Environmental Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China.

The aqueous photodegradation of the widely used antibiotic chlortetracycline（CTC） was investigated under simulated *** quantum yield of photodegradation increased from 3.3 × 10-4 to 8.5 × 10-3 within the pH range of 6.0 to *** presence of Ca2＋,Fe3＋,and NO3-enhanced the photodegradation of CTC,whereas Mg2＋,Mn2＋,and Zn2＋ inhibited the degradation with the order Mn2＋ Zn2＋ Mg2＋ at pH *** monovalent cations（Na＋ and K＋） had negligible effect on the photolysis of *** acid（FA） decreased the photodegradation of CTC due to light screening *** peroxide（H2O2） was formed concurrently with direct photodegradation of *** generation rate of H2O2 increased from 0.027 to 0.086 μmol/（***） when the pH ranged from 6.0 to *** CTC solution was about three-fold more toxic to the Photobacterium phosphoreum bacteria after irradiation,suggesting that the photoproducts and H2O2 formed in the CTC solution exhibited high risk on the *** LC-ESI（＋）-MS,the photoproducts of CTC were *** direct photodegradation of CTC was involved in hydroxylation and N-demethyl/dedismethyl *** main photoproducts included the iso-CTC analog containing hydroxyl groups（m/z 511.4 and 495.4）,and the N-demethyl/dedismethyl products of the photoproduct m/z 495.4（m/z 481.3 and 467.4）.In addition,the photochemical dechlorination of CTC led to tetracycline（m/z 445.5）.

关键词： chlortetracycline direct photodegradation phototoxicity photoproducts

Genetic variations of beta 2-adrenergic receptor gene are associated with essential hypertension in Xinjiang Kazakans

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Journal of Geriatric Cardiology 2010年第1期7卷 52-57页

作者： Zhi-tao Yan Nan-Fang Li Jin yang Ling Zhou Hui Liu Qin Luo The Center of Diagnosis Treatment and Research of Hypertension in Xinjiang Urumqi 830001 China

Objective The aims of the present study were to investigate the associations of 46 A〉G, 79 C〉G, 491 C〉T and 659 C〉G genetic variants of the human beta 2-adrenergic receptor （β2-AR）, ADRB2, gene with essential hypertension （EH） in Xinjiang Kazakans *** A gender-matched case-control （271 hypertensive cases and 267 normotensive controls） study was used to investigate the associations of the four variations in the coding region of ADRB2 with EH. The genotypes of the variants were identified by the polymerase chain reaction and restriction fragment length polymorphism （PCR-RFLP） methods. Results 46 A〉G, 79 C〉G and 659 C〉G polymorphisms were common in the Kazakan population, but 491 C〉T was a mutation （frequency ofT allele was only 0.003） and only found in EH group. The fxequency distributions of genotypes and alleles for 659 C〉G between the EH and control groups was significantly different （P〈0.05）, while those for 46 A〉G and 79 C〉G polymorphisms were not statistically different. Logistic regression analysis suggested that the G allele of 659 C〉G polymorphism was a risk factor for hypertension （minor allele vs common homo; odds ratio, 13.240, 95% CI, 4.052-43.274; P〈0.05）. Covariance analysis showed that systolic and diastolic blood pressure levels in GG＋CG group of 659 C〉G were significantly higher than those in the CC group, but no significant difference of blood pressure were found between common homo and minor allele for 46 A〉G and 79C〉G polymorphisms. Haplotype analysis showed that two hyplotypes, HI： 46A-79C-491C-523C（48%）and H5：46A-79C-491C-659G, were associated with *** ADRB2 genetic variants may play independent roles in the molecular genetic mechanism of EH in Xinjiang Kazakans population （d Geriatr Cardio12010; 7：52-57）.

关键词： β2-adrenergic receptor gene variant essential hypertension haplotype Xinjiang Kazakan

Variations in the quality parameters and gluten proteins in synthetic hexaploid wheats solely expressing the Glu-D1 locus

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Journal of Integrative Agriculture 2022年第7期21卷 1877-1885页

作者： DAI Shou-fen CHEN hai-xia LI Hao-yuan yang Wan-jun Zhai Zhi LIU Qian-yu LI Jian YAN Ze-hong Triticeae Research Institute Sichuan Agricultural UniversityChengdu 611130P.R.China State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Chengdu 611130P.R.China

This study evaluated the quality potential of seven synthetic hexaploid wheats(2 n=6 x=42, AABBDD) expressing only allelic variation at Glu-D1 of Aegilops tauschii(SHWSD). Major quality parameters related to dough strength, gluten proteins(including high-molecular-weight glutenin subunits(HMW-GS) and low-molecular-weight glutenin subunits(LMW-GS), gliadins), and their ratios between SHWSD and the weak gluten wheat control Chuannong 16(CN16) were measured in at least three environments(except STD7). The zeleny sedimentation value(ZSV), dough development time(DDT), dough stability time(DST), and farinograph quality number(FQN) of SHWSD were considered stable under different environments, with their respective ranges being 8.00–17.67 mL, 0.57–1.50 min, 0.73–1.80 min, and 9.50–27.00. The ZSV, DDT, DST, and FQN of SHWSD were smaller than those of CN16, suggesting that SHWSD had a weaker dough strength than CN16. Although SHWSD had a lower gluten index than CN16, its wet and dry gluten contents were similar to or even higher than those of CN16 in all environments tested. The protein content of grains(12.81–18.21%) and flours(14.20–20.31%) in SHWSD was higher than that in CN16. The amount of HMW-GS in SHWSD sharply decreased under the expression of fewer HMW-GS genes, and the LMW-GS, gliadins, and total glutenins were simultaneously increased in SHWSD in comparison with CN16. Moreover, SHWSD had higher ratios of LMWGS/glutenin and gliadin/glutenin but a lower ratio of HMW-GS/glutenin than CN16. These results provide necessary information for the utilization of SHWSD in weak-gluten wheat breeding.

关键词： synthetic hexaploid wheats(SHWs) Ae.tauschii Glu-D1 weak-gluten wheat quality

Exosome is involved in liver graft protection after remote ischemia reperfusion conditioning

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Hepatobiliary & Pancreatic Diseases International 2023年第5期22卷 498-503页

作者： Jian-Hui Li Jun-Jun Jia Ning He Xue-Lian Zhou Yin-Biao Qiao hai-yang Xie Lin Zhou Shu-Sen Zheng Department of Hepatobiliary and Pancreatic Surgery Department of Liver TransplantationShulan(Hangzhou)HospitalZhejiang Shuren University School of MedicineHangzhou 310022China NHC Key Laboratory of Combined Multi-organ Transplantation Hangzhou 310022China Division of Hepatobiliary Pancreatic Surgery First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Endocrinology Children’s HospitalZhejiang University School of MedicineHangzhou 310052China

Background:Remote ischemic perconditioning(RIPerC)has been demonstrated to protect grafts from hepatic ischemia-reperfusion injury(IRI).This study investigated the role of exosomes in RIPerC of liver grafts in ***:Twenty-five rats(including 10 donors)were randomly divided into five groups(n=5 each group):five rats were used as sham-operated controls(Sham),ten rats were for orthotopic liver transplantation(OLT,5 donors and 5 recipients)and ten rats were for OLT+RIPerC(5 donors and 5 recipients).Liver architecture and function were ***:Compared to the OLT group,the OLT+RIPerC group exhibited significantly improved liver graft histopathology and liver function(P<0.05).Furthermore,the number of exosomes and the level of P-Akt were increased in the OLT+RIPerC ***:RIPerC effectively improves graft architecture and function,and this protective effect may be related to the increased number of *** upregulation of P-Akt may be involved in underlying mechanisms.

关键词： Exosome P-Akt Ischemia-reperfusion injury Remote ischemic perconditioning

Water distribution extracted from mining subsidence area using Kriging interpolation algorithm

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中国有色金属学会会刊：英文版 2011年第S3期21卷 723-726页

作者： DAI Hua-yang, REN Li-yan, WANG Meng, XUE hai-bing College of Geosicence and Surveying Engineering, China University of Mining & Technology, Beijing 100083, China College of Geosicence and Surveying Engineering China University of Mining & Technology Beijing 100083 China

By comprehensively analyzing the data of geology and mining, Kriging algorithm was introduced to analyze the thematic information of geological data, to rapidly extract mining parameters for predicting mining subsidence, and to effectively integrate geomorphology and predict information. As a result, the change information of water body is successfully detected from the prediction of surface subsidence due to mining activity. Analysis shows that the elevation of farmland in the west side of water body will be lower than ever, and the west part farmland will be submerged. However, there is no evidence for impacting the villages. All the information provides a reference for efficiently assessing environmental impact due to mining activity, which can help to govern the subsidence of the area reasonably.

关键词： Kriging interpolation water body mining subsidence prediction parameters data fusion

Correlation of An Ultrasonic Scoring System and Intraoperative Blood Loss in Placenta Accreta Spectrum Disorders: A Retrospective Cohort Study

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Biomedical and Environmental Sciences 2021年第2期34卷 163-169页

作者： CHEN Lian SHI Hui Feng JIANG hai SHI Xiao Ming WANG Yuan Yuan ZHANG Ai Qing CHONG Yi Wen ZHAO yang Yu Department of Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China

Objective This study aims to investigate the correlation of an ultrasonic scoring system with intraoperative blood loss(IBL) in placenta accreta spectrum(PAS) *** A retrospective cohort study was conducted between January 2015 and November *** data for patients with PAS have been obtained from medical records. Generalized additive models were used to explore the nonlinear relationships between ultrasonic scores and IBL. Logistic regressions were used to determine the differences in the risk of IBL ≥ 1,500 m L among groups with different ultrasonic *** A total of 332 patients participated in the analysis. Generalized additive models showed a significant positive correlation between score and blood loss. The amount of IBL was increased due to the rise in the ultrasonic score. All cases were divided into three groups according to the scores(low score group: ≤ 6 points, n = 147;median score group: 7-9 points, n = 126;and high score group: ≥ 10 points, n = 59). Compared with the low score group, the high score group showed a higher risk of IBL≥ 1,500 m L [odds ratio, 15.09;95% confidence interval(3.85, 59.19);P ≤ 0.001] after a multivariable *** The risk of blood loss equal to or greater than 1,500 m L increases further when ultrasonic score greater than or equal to 10 points, the preparation for transfusion and referral mechanism should be considered.

关键词： Ultrasonic scoring system Intraoperative blood loss Placenta accreta spectrum disorders