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Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science China Chemistry 2025年第01期 186-191页

作者： Hai Zou yunfeng Bao Xueshang Xin yu Qi Tengfeng Xie Fuxiang Zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

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NUMERICAL SI MULATION OF MOVING SCOUR BOUNDARY AND TURBULENCE FLOWAROUND SUBMARINE PIPElinES

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Journal of Hydrodynamics 2005年第4期17卷 404-411页

作者： LI yu-cheng LU lin State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

A two dimensional vertical mathematical model is proposed in this paper for simulating the equilibrium profile of local scour around submarine pipelines. The current model is composed of a new k-ε turbulence model, fitting moving boundary with pre-meshed grid lines and incipient criterion of shear stress for sediments. Employing the proposed model, an instance is carried out numerically and compared with experiments. The calculation results agree well with the experiments. It shows that the improved two equation turbulence model, adopted in this paper is appropriate to simulating the turbulent flow ficld around submarine pipelines, fitting moving boundary with pre-mcshed grid lines method is efficient for moving boundary problems in a multiply connected domain and the stability evaluation method for seabed with critical shear stress based on log-wall law is a reliable choice.

关键词： numerical simulation submarine pipeline local scour moving boundary turbulence model

Preparation of a functional fracturing fluid with temperature-and salt-resistance,and low damage using a double crosslinking network

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Petroleum Science 2023年第5期20卷 3223-3230页

作者： Yang Zhang An Chen Jin-Cheng Mao Song-Hai Qin Jin Li Xiao-Jiang Yang chong lin Zhi-yu Huang Ya-Fei Liu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan610500China Development Division PetroChina Southwest Oil and Gas Field CompanyChengduSichuan610066China Downhole Services Company CNPC Bohai Drilling Engineering Company LtdRenqiuHebei062550China Sinopec Zhongyuan Oilfield Company PuyangHenan457001China

Fracturing fluids(FFs)have been widely used to stimulate the tight ***,current FFs will not only lose their rheological property at high temperatures and high salt but also show an incomplete gel-breaking ***,a double crosslinking network FF with pretty superiorities in rheology and low damage to the core was constructed by introducing both physical crosslinking and chemical crosslinking into the *** construction of double crosslinking networks enhanced the rheology of this functional *** particle sizes of gel-breaking fluids are mainly distributed in 1.0e10,000 nm;furthermore,for every 10,000 mg/L increase in salinity,the particle size of the gel-breaking fluid is decreased by almost *** adsorption capacity(linity at 20℃.Moreover,the adsorption of gel-breaking fluids on the rock decreased first and then kept stable with temperature increasing at a salinity of ≤30,000 mg/L,however,showed the opposite trend at 40,000 mg/*** results of rheology,particle size,static adsorption,and core damage showed that this functional FF could be an alternative for the stimulation of a tight reservoir with high temperature and recycling of produced water with high salinity.

关键词： Fracturing fluid Temperature-and salt-resistance Particle size Static adsorption Low damage

A Novel Self-Supervised Learning Network for Binocular Disparity Estimation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 209-229页

作者： Jiawei Tian yu Zhou Xiaobing Chen Salman A.AlQahtani Hongrong Chen Bo Yang Siyu Lu Wenfeng Zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia School of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical *** study proposes a novel end-to-end disparity estimation model to address these *** approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting *** study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and *** model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video *** results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing ***,the model exhibited faster convergence during training,contributing to overall performance *** study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.

关键词： Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： Liang-Liang Dong yu-lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Analysis of Semi-Supervised Text Clustering Algorithm on Marine Data

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Computers, Materials & Continua 2020年第7期64卷 207-216页

作者： yu Jiang Dengwen yu Mingzhao Zhao Hongtao Bai chong Wang Lili He College of Computer Science and Technology Jilin UniversityChangchun130012China A Key Laboratory of Symbolic Computation and Knowledge Engineering Jilin UniversityChangchun130012China Department of Engineering Mechanics State Marine Technical University of St.PetersburgSt.Petersburg190008Russia

Semi-supervised clustering improves learning performance as long as it uses a small number of labeled samples to assist un-tagged samples for *** paper implements and compares unsupervised and semi-supervised clustering analysis of BOA-Argo ocean text *** K-Means and Affinity Propagation(AP)are two classical clustering *** Election-AP algorithm is proposed to handle the final cluster number in AP clustering as it has proved to be difficult to control in a suitable ***-supervised samples thermocline data in the BOA-Argo dataset according to the thermocline standard definition,and use this data for semi-supervised cluster *** semi-supervised clustering algorithms were chosen for comparison of learning performance:Constrained-K-Means,Seeded-K-Means,SAP(Semi-supervised Affinity Propagation),LSAP(Loose Seed AP)and CSAP(Compact Seed AP).In order to adapt the single label,this paper improves the above algorithms to SCKM(improved Constrained-K-Means),SSKM(improved Seeded-K-Means),and SSAP(improved Semi-supervised Affinity Propagationg)to perform semi-supervised clustering analysis on the data.A DSAP(Double Seed AP)semi-supervised clustering algorithm based on compact seeds is proposed as the experimental data shows that DSAP has a better clustering *** unsupervised and semi-supervised clustering results are used to analyze the potential patterns of marine data.

关键词： Unsupervised learning semi-supervised learning text clustering

The Impact of General Correlation Under Multi-Period Mean-Variance Asset-Liability Portfolio Management

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Journal of Systems Science & Complexity 2023年第6期36卷 2515-2535页

作者： WU Xianping WU Weiping lin yu School of Mathematics and Statistics Guangdong University of TechnologyGuangzhou510520China School of Economics and Management Fuzhou UniversityFuzhou350108China

This paper studies the multi-period mean-variance(MV)asset-liability portfolio management problem(MVAL),in which the portfolio is constructed by risky assets and *** is worth mentioning that the impact of general correlation is considered,i.e.,the random returns of risky assets and the liability are not only statistically correlated to each other but also correlated to themselves in different time *** a model with a general correlation structure extends the classical multiperiod MVAL models with assumption of independent *** authors derive the explicit portfolio policy and the MV efficient frontier for this ***,a numerical example is presented to illustrate the efficiency of the proposed solution scheme.

关键词： Asset-liability management dynamic programming mean-variance multi-period portfolio stochastic correlated returns

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： Zhen-yu Ouyang Jian-zhong lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a *** in the past 20 years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid *** paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle *** this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be ***,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction

Significant reduction of ammonia emissions while increasing crop yields using the 4R nutrient stewardship in an intensive cropping system

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Journal of Integrative Agriculture 2023年第6期22卷 1883-1895页

作者： ZHANG chong WANG Dan-dan ZHAO Yong-jian XIAO yu-lin CHEN Huan-xuan LIU He-pu FENG Li-yuan yu Chang-hao JU Xiao-tang College of Tropical Crops Hainan UniversityHaikou 570228P.R.China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China

Ammonia (NH_3) emissions should be mitigated to improve environmental *** are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target ***,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize *** the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N *** using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),*** manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N *** return exerted a minor effect on NH_3 *** results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.

关键词： ammonia emission crop yield 4R nutrient stewardship partial manure substitution winter wheat–summer maize cropping system