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Degradation of chemical and mechanical properties of cements with different formulations in CO_(2)-containing HTHP downhole environment

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Petroleum Science 2023年第2期20卷 1119-1128页

作者： Wei Yan Hao-Guang Wei Nguu Dickson Muchiri Fu-li li jing-ru Zhang Zheng-Xian Xu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Sinopec Petroleum Engineering Technology Research Institute Co. Ltd.Beijing102206China

The increasing energy demand has pushed oil and gas exploration and development limits to extremely challenging and harsher HTHP (High Temperature and High Pressure) environments. Maintaining wellbore integrity in these environments, particularly in HPHT reservoirs with corrosive gases, presents a significant challenge. Robust risk evaluation and mitigation strategies are required to address these reservoirs' safety, economic, and environmental uncertainties. This study investigates chemo-mechanical properties degradations of class G oil well cement blended with silica fume, liquid silica, and latex when exposed to high temperature (150 °C) and high partial pressure of CO_(2) saturated brine. The result shows that these admixtures surround the cement grains and fill the interstitial spaces between the cement particles to form a dense crystal system of C–S–H. Consequently, the cement's percentage of pore voids, permeability, and the content of alkali compounds reduce, resulting in increased resistance to CO_(2) corrosion. liquid silica, a specially prepared silica suspension, is a more effective alternative to silica fume in protecting oil well cement against CO_(2) chemical degradation. Micro-indentation analysis shows a significant deterioration in the mechanical properties of the cement, including average elastic modulus and hardness, particularly in the outer zones in direct contact with corrosive fluids. This study highlights the significance of incorporating admixtures to mitigate the effects of CO_(2) corrosion in HPHT environments and provides a valuable technique for quantitatively evaluating the mechanical-chemical degradation of cement sheath.

关键词： HPHT reservoirs Oil well cement CO_(2)corrosion Chemo-mechanical Mechanical properties Micro-indentation

Agricultural Ontology Based Feature Optimization for Agricultural Text Clustering

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Journal of Integrative Agriculture 2012年第5期11卷 752-759页

作者： SU Ya-ru WANG ru-jing CHEN Peng WEI Yuan-yuan li Chuan-xi HU Yi-min Institute of Intelligent Machines Chinese Academy of Sciences Hefei 230031 P.R.China School of Information Science and Technology University of Science and Technology of China Hefei 230026 P.R.China

Feature optimization is important to agricultural text mining. Usually, the vector space model is used to represent text documents. However, this basic approach still suffers from two drawbacks： thecurse of dimension and the lack of semantic information. In this paper, a novel ontology-based feature optimization method for agricultural text was proposed. First, terms of vector space model were mapped into concepts of agricultural ontology, which concept frequency weights are computed statistically by term frequency weights; second, weights of concept similarity were assigned to the concept features according to the structure of the agricultural ontology. By combining feature frequency weights and feature similarity weights based on the agricultural ontology, the dimensionality of feature space can be reduced drastically. Moreover, the semantic information can be incorporated into this method. The results showed that this method yields a significant improvement on agricultural text clustering by the feature optimization.

关键词： agricultural ontology feature optimization agricultural text clustering

Mechanism of action of linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： Huan Pei Ren-lin li Xin-Ran Song Qian-Qian Wan Yu-Ming Wang Han-Zhou li Wei-Quan Xu Jia-Bao liao Wei-Bo Wen jing Miao Huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle

Carbon Chain Length Determines Inhibitory Potency of Perfluoroalkyl Sulfonic Acids on Human Placental 3β-Hydroxysteroid Dehydrogenase 1:Screening,Structure-Activity Relationship,and In Silico Analysis

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Biomedical and Environmental Sciences 2023年第11期36卷 1015-1027页

作者： TANG Lu Ming MAO Bai Ping ZHANG Bing ru li jing jing TANG Yun Bing li Hui Tao GE Ren Shan Department of Emergency Medicine The Second Affiliated Hospital and Yuying Children Hospital of Wenzhou Medical UniversityWenzhou 325000ZhejiangChina Department of Anesthesiology The Second Affiliated Hospital and Yuying Children Hospital of Wenzhou Medical UniversityWenzhou 325000ZhejiangChina Department of Obstetrics and Gynecology The Second Affiliated Hospital and Yuying Children Hospital of Wenzhou Medical UniversityWenzhou 325000ZhejiangChina Key Laboratory of Structural Malformations in Children of Zhejiang Province Wenzhou 325000ZhejiangChina

Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 *** Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS–MS,and human aromatase activity was determined by *** PFSA inhibited human 3β-HSD1 structure-dependently in the order:perfluorooctanesulfonic acid(PFOS,half-maximum inhibitory concentration,IC50:9.03±4.83μmol/L)>perfluorodecanesulfonic acid(PFDS,42.52±8.99μmol/L)>perfluoroheptanesulfonic acid(PFHpS,112.6±29.39μmol/L)>perfluorobutanesulfonic acid(PFBS)=perfluoropentanesulfonic acid(PFPS)=perfluorohexanesulfonic acid(PFHxS)=perfluorododecanesulfonic acid(PFDoS)(ineffective at 100μmol/L).6:2FTS(1H,1H,2H,2H-perfluorooctanesulfonic acid)and 8:2FTS(1H,1H,2H,2H-perfluorodecanesulfonic acid)did not inhibit human 3β-*** and PFHpS are mixed inhibitors,whereas PFDS is a competitive ***,1–10μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 *** analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent *** 100μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase *** Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS(C8),with inhibitory potency of PFOS>PFDS>PFHpS>PFBS=PFPS=PFHxS=PFDoS=6:2FTS=8:2FTS.

关键词： 3β-hydroxysteroid dehydrogenase 1 Docking analysis Perfluorooctanesulfonic acid Progesterone Structure-activityrelationship

Biological sources, paleoenvironment, and organic matter enrichment in source rocks of the Ordovician Majiagou Formation, Ordos Basin, China:Evidence from biomarkers,microfossils, and inorganic geochemical analyses

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Journal of Palaeogeography 2024年第1期13卷 92-115页

作者： jing-jing Cao Wen-Zhe Gang Shang-ru Yang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Bejing)Beijing 102249China College of Geosciences China University of Petroleum(Bejing)Beijing 102249China Oil and Gas Technology Research Institute PetroChina Changqing Oifield CompanyXi'an 710018Shaanxi ProvinceChina

Carbonate deposits in the Ordovivian Majiagou Formation are significant source rocks for natural gas generation in the Ordos Basin, northwestern China. Previous studies mainly focused on the organic matter enrichment mechanism of shales rather than carbonate rocks. The biological sources and paleoenvironment of carbonate source rocks, and the main controlling factors of organic matter enrichment in the carbonate source rocks were studied in this paper in combination with evidence from biomarkers, microfossils and inorganic geochemistry analysis. The results show that four types of microfacies were identified in the Majiagou Formation, respectively as: mud flat microfacies, mud-dolomite flat microfacies, dolomite flat microfacies, and open marine microfacies. The biological sources of organic matter are chiefly planktonic algae, followed by bacteria. The mud flat and mud-dolomite flat contain a high abundance of terrigenous detrital inputs, as indicated by the high content of Al_(2)O_(3), TiO_(2), Th, and Zr. The low Sr/Cu and high Rb/Sr values reveal warm and humid paleoclimate conditions in the mud flat and mud-dolomite flat, whereas the dolomite flat and open marine were likely formed in hot and arid paleoclimate conditions. The mud flat and mud-dolomite flat deposits were characterized by high paleoproductivity of the Majiagou Formation. Low Sr/Ba values were found in the mud flat samples, indicating fresh to brackish water condition, whereas samples of other facies have a relatively high degree of salinity. Based on U_(auth), Mo_(auth), Cr_(auth), Co_(auth), δCe, and δEu values, the mud flat microfacies was formed in a suboxic and anoxic environment, whereas the mud-dolomite flat, dolomite flat and open marine microfacies were within dysoxic to oxic conditions. A model of organic matter enrichment in the Majiagou Formation is thus established. The level of terrigenous detrital inputs is the principal factor of organic matter enrichment in the Majiagou Formation,

关键词： Biological source Microfacies Trace elements Organic matter Majiagou Formation Ordos Basin

Analysis on MAV/UAV cooperative combat based on complex network

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Defence Technology（防务技术） 2020年第1期16卷 150-157页

作者： Jie-ru Fan Dong-guang li ru-peng li Yue Wang Beijing Institute of Technology BeijingChina Beijing Electro-mechanical Engineering Institute BeijingChina Beijing Institute of Electronic System Engineering BeijingChina

A formation model of manned/unmanned aerial vehicle(MAV/UAV) collaborative combat can qualitatively and quantitatively analyze the synergistic ***,there is currently no effective and appropriate model construction method or theory,and research in the field of collaborative capability evaluation is basically *** to the actual conditions of cooperative operations,a new MAV/UAV collaborative combat network model construction method based on a complex network is *** analyzing the characteristic parameters of the abstract network,the index system and complex network are ***,a method for evaluating the synergistic effect of the cooperative combat network is *** method provides assistance for the verification and evaluation of MAV/UAV collaborative combat.

关键词： Complex network Stochastic network MAV/UAV collaborative combat Evaluation

Female choice impacts resident male takeover in golden snub-nosed monkeys(Rhinopithecus roxellana)

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Zoological Research 2018年第4期39卷 266-271页

作者： Gu Fang jing Chen ru-liang Pan Xiao-Guang Qi Bao-Guo li College of life Sciences Northwest University Shaanxi Key Laboratory for Animal Conservation Northwest University School of Anatomy Physiology and Human Biology University of Western Australia

In primate species with social systems consisting of one-male breeding units （OMUs）, resident male takeover represents a major challenge to individual reproductive success and mating strategies. The golden snub-nosed monkey （Rhinopithecus roxellana） is characterized by large multilevel societies （MLS） comprised of several OMUs and all-male units （AMUs）; however, the factors and mechanisms associated with resident male takeover, which offer important insight into primate reproduction and social strategies, are still poorly understood. Based on 5-year monitoring data from a free-ranging herd of golden monkeys from the Qinling Mountains in China, we categorized three phases of an OMU, that is, a rising phase, developing phase, and declining phase. The rising and declining phases were unstable periods in which male takeover in an OMU might occur. Factors causing takeover, such as leader male rank, fighting ability, reproduction rate, and affiliation （proximity, allogrooming）, were analyzed for males and females and for different OMUs. Results indicated that the new resident male＇s fighting ability was lower than that of the former resident male in 23 cases. After replacement, the rank order of the new resident male significantly declined. Females involved in a takeover increased their distance from the resident male and decreased mating frequency during the three months prior to takeover. Females with infants under one-year-old had a marked effect on the specific time of takeover occurrence. These results suggested that female choice was the main factor deciding whether a takeover attempt was successful. Furthermore, rather than male conflict, females more often initiated and affected takeover and outcome, implying that the social status and competitive ability of the males played lesser roles during takeover.

关键词： Rhinopithecus roxellana Female matechoice Takeover Resident male tenure Socialnetwork analysis

Deposition of Diamond-like Carbon Films with Femtosecond KrF Laser Pulses

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Chinese Physics Letters 2000年第7期17卷 540-541页

作者： YAO Dong-Sheng liU jing-ru WANG li-Ge YU Chang-Xuan ZHAN ru-juan Department of Modern Physics University of Science and Technology of ChinaHeFei 230026 Third Division Northwest Institute of Nuclear TechnologyXVan 710024

Hydrogen-free diamond-like carbon (DLC) films with the optical band gaps of 2.0-2.7 e V and the microhardness of 40-55 GPa are deposited by femtosecond KrF laser pulses. The film microstructure of nanometer spheroid is observed. The filrn microhardness is improved with the increase of ion kinetic energy of plasma plume from 300 to 600 eV. The characteristics of DLC film deposition with fs pulses is discussed.

关键词： KrF Femto film

Compound Danshen Dripping Pills combined with isosorbide mononitrate for angina pectoris: A systematic review and a Meta-analysis

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Chinese Herbal Medicines 2024年第4期16卷 622-637页

作者： ru Wang jing Hu Yuanyuan li Hong Yin Department of Pharmacy Medical Supplies CenterPLA General HospitalBeijing 100853China

Objective: To evaluate the efficacy of Compound Danshen Dripping Pills(CDDP) combined with isosorbide mononitrate(ISMN) versus ISMN alone for treating angina pectoris in ***: The Pub Med, Web of Science, Cochrane library, Embase China National Knowledge Infrastructure, China Biomedical literature Service System, Chinese Medical Journal Database, and Wan Fang MED databases were searched from inception to November 2022. Randomized controlled trials(RCTs) and cohort studies were included. The primary outcomes were angina symptom and electrocardiography(ECG) efficacy, angina symptom efficacy, and ECG efficacy. The protocol was registered with PROSPERO No. ***: Our study included 7 245 patients with angina(59 RCTs, 11 cohort studies). When ISMN was combined with CDDP, the efficacy of angina symptom and ECG [odds ratio(OR) = 4.824, 95% confidence interval(CI) = 3.636–6.401, P = 0.000], the efficacy of angina symptom(OR = 4.347, 95% CI = 3.635–5.198,P = 0.000), the efficacy of ECG(OR = 3.364, 95% CI = 2.767–4.089, P = 0.000) were better than that of patients treated with ISMN alone. CDDP combined with ISMN was superior to ISMN alone in reducing triglyceride(TG) [mean difference(MD) =-35.176, 95% CI =-37.439 to-32.912, P = 0.000], total cholesterol(TC)(MD =-24.296, 95% CI =-26.429 to-22.163, P = 0.000), the duration of angina attack(MD =-1.991, 95% CI =-2.349 to-1.633, P = 0.000), and the frequency of angina attack [standardized MD(SMD) =-2.840, 95% CI =-3.416 to-2.265, P = 0.000]. There was no increase in adverse events between CDDP combined with ISMN and ISMN alone(OR = 0.513, 95% CI = 0.421–0.626, P = 0.000).Conclusion: CDDP combined with ISMN improved treatment efficacy and was well tolerated. Therefore,this combination could be used as an alternative treatment. However, clinical and patient conditions should be considered.

关键词： angina pectoris Compound Danshen Dripping Pills isosorbide mononitrate Meta-analysis systematic review