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Distribution Patterns of Calcite Cement in the Turbidite Sandstones of the Shahejie Formation in the Dongying Depression,Eastern China

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Acta Geologica Sinica(English Edition) 2022年第3期96卷 1041-1056页

作者： ZHANG YongWang QU Zhengyang State Key Laboratory of Petroleum Resources and Prospecting Beijing 102249China College of Geosciences China University of Petroleum-BeijingBeijing 102249China No.4 Oil Production Plant PetroChina Changqing Oilfield CompanyYinchuan 718500China

Calcite cements are volumetrically dominant among the most diagenetic constituents in turbidite sandstones of the Paleogene Shahejie Formation in the Dongying Depression.The results show carbonate cements mainly occur in three phases:Calcite I(pre-compaction),Calcite II(post-compaction)and ankerite in the turbidite sandstone.The isotopic composition of Calcite I and Calcite II range from−4.3‰to 4.4‰,−3.5‰to 4.3‰PDB,respectively,suggesting that the calcite cements are mainly derived from the interbedded shales.The early calcite cement precipitated from the mixing of lacustrine and meteoric waters at 38-69℃.The late-phase calcite precipitated from pore waters modified by water-rock interactions at 64-126℃.Two distribution patterns of calcite cements can be identified,depending on their position within the sandstone.The peripheral cementation of the sandstones is near the sand-shale contact.The development of cement is controlled by sandstone thickness and the properties of the interbedded shale.For scattered cementation,the distribution of the calcite cement is not controlled by the sand-shale contact.Calcite cement was preferentially distributed in coarse-grained sandstones,indicating that sandstones with high original permeability are the preferred pathway for the migration of early diagenetic fluids.

关键词： turbidite sandstone calcite cement distribution patterns Dongying Depression

Substrate matters:The influences of substrate layers on the performances of thin-film composite reverse osmosis membranes

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Chinese Journal of Chemical Engineering 2017年第11期25卷 1676-1684页

作者： Jie Li,Mingjie Wei YongWang State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced MaterialsCollege of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Thin-film composite(TFC) reverse osmosis(RO) membranes are playing the dominating role in desalination.Tremendous efforts have been put in the studies on the polyamide selective layers. However, the effect of the substrate layers is far less concerned. In this review, we summarize the works that consider the impacts of the substrates, including pore sizes, surface hydrophilicity, on the processes of interfacial polymerization and consequently on the morphologies of the active layers and on final RO performances of the composite membranes. All the works indicate that the pore sizes and surface hydrophilicity of the substrate evidently influence the RO performances of the composite membranes. Unfortunately, we find that the observations and understandings on the substrate effect are frequently varied from case to case because of the lack of substrates with uniform pores and surface chemistries. We suggest using track-etched membranes or anodized alumina membranes having relatively uniform pores and functionalizable pore walls as model substrates to elucidate the substrate effect.Moreover, we argue that homoporous membranes derived from block copolymers have the potential to be used as substrates for the large-scale production of high-performances TFC RO membranes.

关键词： Reverse osmosis Thin-film composite Interracial polymerization Homoporous membranes Sobstrate effect

Urban Agglomerations in China: Characteristics and Influencing Factors of Population Agglomeration

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Chinese Geographical Science 2023年第4期33卷 719-735页

作者： CAO YongWang ZHANG Rongrong ZHANG Dahao ZHOU Chunshan School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China

Urban agglomeration(UA)is an advanced spatial economic form formed and developed in the process of rapid industrialization and urbanization,and an important carrier of urbanization and economic development.The economy has developed rapidly in the recent decades of China,and the UAs have also developed rapidly.However,as a large population country,the population distribution and changes of UAs in China has unique characteristics.Using the fifth,sixth and seventh population census data,spatial auto-correlation and spatial econometric models,we analyzed the spatial-temporal evolution characteristics and influencing factors of population agglomeration in China’s UAs.Results revealed that:1)from 2000 to 2020,the population gradually converged into UAs,and the characteristics of population agglomeration in different development degree of UAs differ.The higher the development degree of UA,the higher the population agglomeration degree.Besides,UAs are the main area with the most significant population agglomeration degree,and the spatial autocorrelation show that the cities with similar degree tend to be concentrated in space.The urban population gathering in UAs has a certain positive spillover effect on population size of neighboring cities.2)Economic development and social conditions factors are important factors affecting population agglomeration degree in UAs.The main factors of population gather into UAs are similar with the outside UAs,but the positive promotion of urbanization rate and proportion of tertiary industry in GDP on population agglomeration of UAs in China are enhancing from 2000 to 2020.Meanwhile,the other factors,such as high-quality public services,good urban living environment conditions,high-quality medical and educational resources,are also important factors to promote urban population gather into UAs.This study provides a basis for formulating the development planning of UAs in China,and enriches the relevant theoretical research of population evolution and influencing factors of UAs.

关键词： urban agglomerations(UAs) population agglomeration influencing factors spatial econometric models China

Modeling and Stability Analysis of a Flexible Rotor Based on the Timoshenko Beam Theory

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Acta Mechanica Solida Sinica 2020年第3期33卷 281-293页

作者： YongWang Zhang Xiaodong Yang Wei Zhang Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of Technology100124 BeijingChina

Based on the Timoshenko beam theory,a novel mathematical model of a rotating shaft with centrifugal terms is developed by using Hamilton^principle and Euler angles.The associated conventional model is provided for comparison purpose.The features of the proposed mathematical model are discussed based on some selected coordinate systems.The frequencies and modes are investigated to show the influences of centrifugal terms on the stability of the gyroscopic systems.The results show that the novel model proposed may lose stability due to the centrifugal terms.It is also found that the backward precession mode can be changed into a forward one beyond the critical rotating velocity.

关键词： Spinning Timoshenko beam Euler angles Centrifugal terms Stability analysis

Protective effect of L-arginine preconditioning on ischemia and reperfusion injury associated with rat small bowel transplantation

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World Journal of Gastroenterology 2005年第19期11卷 2994-2997页

作者： BinCao NingLi YongWang Jie-ShouLi DepartmentofSurgery NanjingUniversityMedicalSchoolTheFirstAffiliatedHospitalofNanjingMedicalUniversityNanjing210029JiangsuProvinceChina DepartmentofSurgery NanjingUniversityMedicalSchoolNanjing210002JiangsuProvinceChina

AIM: To investigate the protective effect and possible mechanism of L-arginine preconditioning on ischemia and reperfusion injury associated with small bowel transplantation (SBT).METHODS: Male inbred Wistar rats weighting between 180 and 250 g were used as donors and recipients in thestudy. Heterotopic rat SBT was performed according to the techniques of Li and Wu. During the experiment, intestinal grafts were preserved in 4 ℃ Ringer's solution for 8 h before being transplanted. Animals were divided into three groups. In group 1, donors received intravenous L-arginine (50 mg/kg, 1 mL) injection 90 min before graft harvesting. However, donors in control group were given normal saline (NS) instead. In group 3, six rats were used as sham-operated control. Specimens were taken from intestinal grafts 15 min after reperfusion. Histological grading, tissue malondialdehyde (MDA) and myeloperoxidase (MPO) levels were assessed. The graft survival of each group was monitored daily until 14 d after transplantation. RESULTS: Levels of MDA and MPO in intestine of shamoperated rats were 2.0±0.22 mmol/g and 0.66±0.105 U/g. Eight hours of cold preservation followed by 15 min of reperfusion resulted in significant increases in tissue MDA and MPO levels. Pretreatment with L-arginine before graft harvesting resulted in lower enhancement of tissue levels of MDA and MPO and the differences were significant (4.71±1.02 mmol/g vs8.02±3.49 mmol/g, 1.03±0.095 U/g vs 1.53±0.068 U/g, P＜0.05). Besides, animals in L-arginine pretreated group had better histological structures and higher 2-wk graft survival rates comparing with that in NS treated group (3.3±0.52 vs6±0.1, 0/6 vs6/6, P＜0.05or 0.01).CONCLUSION: L-arginine preconditioning attenuates ischemia and reperfusion injury in the rat SBT model,which was due to antioxidant activities partially.

关键词： L-精氨酸保护机制预处理小肠移植缺血再灌注损伤

Machine learning predicts atomistic structures of multielement solid surfaces for heterogeneous catalysts in variable environments

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The Innovation 2024年第2期5卷 79-87页

作者： Huan Ma Yueyue Jiao Wenping Guo Xingchen Liu YongWang Li Xiaodong Wen State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China National Energy Center for Coal to Liquids Synfuels China Co.Ltd.Beijing 101400China Beijing Advanced Innovation Center for Materials Genome Engineering IndustryUniversity Cooperation Base between Beijing Information S&T University and Synfuels China Co.Ltd.Beijing 100101China

Solid surfaces usually reach thermodynamic equilibrium through particle exchange with their environment under reactive conditions.A prerequisite for understanding their functionalities is detailed knowledge of the surface composition and atomistic geometry under working conditions.Owing to the large number of possible Miller indices and terminations involved in multielement solids,extensive sampling of the compositional and conformational space needed for reliable surface energy estimation is beyond the scope of ab initio calculations.Here,we demonstrate,using the case of iron carbides in environments with varied carbon chemical potentials,that the stable surface composition and geometry of multielement solids under reactive conditions,which involve large compositional and conformational spaces,can be predicted at ab initio accuracy using an approach that combines the bond valence model,Gaussian process regression,and ab initio thermodynamics.Determining the atomistic structure of surfaces under working conditions paves the way toward identifying the true active sites of multielement catalysts in heterogeneous catalysis.

关键词： surfaces solids environments

Distributionally Robust Optimal Dispatch of Virtual Power Plant Based on Moment of Renewable Energy Resource

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Energy Engineering 2022年第5期119卷 1967-1983页

作者： Wenlu Ji YongWang Xing Deng Ming Zhang Ting Ye Nanjing Power Supply Company of State Grid Jiangsu Electric Power Co. Ltd.Nanjing210019China

Virtual power plants can effectively integrate different types of distributed energy resources,which have become a new operation mode with substantial advantages such as high flexibility,adaptability,and economy.This paper proposes a distributionally robust optimal dispatch approach for virtual power plants to determine an optimal day-ahead dispatch under uncertainties of renewable energy sources.The proposed distributionally robust approach characterizes probability distributions of renewable power output by moments.In this regard,the faults of stochastic optimization and traditional robust optimization can be overcome.Firstly,a second-order cone-based ambiguity set that incorporates the first and second moments of renewable power output is constructed,and a day-ahead two-stage distributionally robust optimization model is proposed for virtual power plants participating in day-ahead electricity markets.Then,an effective solution method based on the affine policy and second-order cone duality theory is employed to reformulate the proposed model into a deterministic mixed-integer second-order cone programming problem,which improves the computational efficiency of the model.Finally,the numerical results demonstrate that the proposed method achieves a better balance between robustness and economy.They also validate that the dispatch strategy of virtual power plants can be adjusted to reduce costs according to the moment information of renewable power output.

关键词： Virtual power plant optimal dispatch uncertainty distributionally robust optimization affine policy

Association between Carotid Intima-media Thickness and Aldehyde Dehydrogenase 2 Glu504Lys Polymorphism in Chinese Han with Essential Hypertension

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Chinese Medical Journal 2016年第12期129卷 1413-1418页

作者： Xiao-Xiang Ma Shu-Zhan Zheng Yan Shu YongWang Xiao-Ping Chen Center of Health Physical Examination and Health Management Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital Chengdu Sichuan 610072 China DePartment of Cardiovascular Medicine West China Hospital Sichuan University Chenqdu Sichuan 610041 China Department of Cardiology The Affiliated Hospital of Luzhou Medical College Luzhou Sichuan 646000 China Department of Cardiology Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital Chengdu Sichuan 610072 China Department of Cardiovascular Xinqiao Hospital Third Military Medical University Chongqing Sichuan 400037 China

Background： Aldehyde dehydrogenase 2 （ALDH2） is involved in the pathophysiological processes of cardiovascular diseases. Recent studies showed that mutant ALDH2 could increase oxidative stress and is a susceptible factor for hypertension. In addition, wild-type ALDH2 could improve the endothelial functions, therefore reducing the risk of developing atherosclerosis. The aim of the present study was to explore the frequency of the Glu504Lys polymorphism of the ALDH2 gene and its relation to carotid intima-media thickness （CIMT） in a group of patients with essential hypertension （EH） and to investigate the association between the Glu504Lys polymorphism and CIMT in Chinese Han patients with EH. Methods： In this study, 410 Chinese Han patients with EH who received physical examinations at the People＇s Hospital of Sichuan Province （China） were selected. DNA microarray chip was used for the genotyping of the Glu504Lys polymorphism of the ALDH2 gene. The differences in CIMT among patients with different Glu504Lys ALDH2 genotypes were analyzed. Results： The mean CIMT of the patients carrying AA/AG and GG genotypes was 1.02 ± 0.31 mm and 0.78 ±0.28 mm, respectively. One-way ANOVA showed that the CIMT of the patients carrying the AA/AG genotype was significantly higher than in the ones carrying the GG genotype （P 〈 0.001）. Multivariate logistic regression showed that the Glu504Lys AA/AG genotype of the ALDH2 gene was one of the major factors influencing the CIMT in patients with EH （odds ratio = 3.73 l, 95% confidence interval = 1.589-8.124, P = 0.001）. Conclusions： The Glu504Lys polymorphism of the ALDH2 gene is associated with the CIMT of Chinese Han patients with EH in Sichuan, China.

关键词： Aldehyde Dehydrogenase 2 Carotid Intima-media Thickness Essential Hypertension Glu504Lys Polymorphism

Deformation mechanism and quantitative characterization of Al2O3 inclusions in powder metallurgy superalloys

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Progress in Natural Science:Materials International 2022年第4期32卷 482-489页

作者： Yefei Feng Fangzheng Ding Qiqiang Duan Jinwen Zou Xiaoming Zhou YongWang Kang Xuqing Wang Science and Technology on Advanced High Temperature Structural Materials Laboratory AEEC Beijing Institute of Aeronautical Materials Institute of Metals Research Chinese Academy of Sciences

By means of implanting inclusions artificially, the evolution law of three-dimensional morphology and size of Al2O3inclusions in FGH96 powder metallurgy(PM) superalloy during hot iso-static pressing(HIP), hot extrusion(HEX) and hot isothermal forging(HIF) process was investigated by SEM and quasi in situ Micronano-CT. The size change of inclusions during different stages was studied quantitatively, the three-dimensional(3D) morphology of the inclusions was characterized, and the deformation mechanism was proposed. The results showed that the inclusions in powder stage were long stripe or plate-like shape. During HIP, Al2O3inclusions were mechanically bonded to the alloy matrix, and its chemical composition, morphology and size remained unchanged. During HEX,Al2O3inclusions were broken and elongated into chain shape due to shear stress. The quantitative relationship between inclusion size after extrusion and extrusion ratio as well as original inclusion size was established. During HIF, the relationship between 3D morphology, size, orientation and deformation of a single inclusion during forging compression was quantitatively characterized by quasi in-situ micronano-CT for the first time. The above evolution law provides theoretical basis and technical support for improving the purity level of powder turbine disk.

关键词： Powder metallurgy superalloy Single inclusion Deformation mechanism Quantitative characterization Micronano-CT