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Vertical grain-size trend of mouth bar in lacustrine fan delta:Flume experiments

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Petroleum Science 2022年第5期19卷 1964-1977页

作者： Ke Zhang Sheng-He Wu Jun-jie Wang Yun-jie xu Zhen-Hua xu Jia-Jia Zhang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China School of Geosciences Yangtze UniversityWuhanHubei 430100China

Field observational previously indicated a mouth bar of a fan delta could exhibit a fining-or coarseningupward trend,which bring a new challenge to the identification of mouth bar in subsurface studies due to the lack of morphological *** studies have indicated that effluent behavior in rivermouth system can affect the vertical grain-size trend of mouth bar,but the drivers and magnitude of this phenomenon are not *** conducted flume experiments to investigate the mechanism and controlling factors of vertical grain-size trend of mouth *** with a steeper slope of the substrate layer,greater discharge,higher sediment/water ratio,and coarser sediment induced a finingupward trend of mouth bar,because the effluent was dominated by strong *** bar in the experiment with a gentler slope of the substrate layer,smaller discharge,lower sediment/water ratio,and finer sediment exhibited a coarsening-upward trend dominated by the friction-dominated *** relationship between the vertical grain-size trend of mouth bar and the gradients of foreset bedding in small-scale flume models and the cut-off of 15°-18°are applicable in natural *** depositional setting to infer depositional process in river-mouth system and analyzing the plane geometry of sandbodies are two steps in the interpretation of ancient fan deltaic rock record.

关键词： Mouth bar Vertical grain-size trend Effluent behavior Inertia Bed friction

Prognostic nomograms for young breast cancer:A retrospective study based on the SEER and METABRIC databases

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Cancer Innovation 2024年第6期3卷 86-99页

作者： Yongxin Li Xinlong Tao Yinyin Ye Yuyao Tang Zhengbo xu Yaming Tian Zhen Liu Jiuda Zhao Breast Disease Diagnosis and Treatment Center of Affiliated Hospital of Qinghai University&Affiliated Cancer Hospital of Qinghai University XiningQinghaiChina Qinghai University XiningQinghaiChina Department of Imaging Affiliated Hospital of Qinghai UniversityXiningQinghaiChina

Background:Young breast cancer(YBC)is a subset of breast cancer that is often more aggressive,but less is known about its *** this study,we aimed to generate nomograms to predict the overall survival(OS)and breast cancer‐specific survival(BCSS)of YBC ***:Data of women diagnosed with YBC between 2010 and 2020 were obtained from the Surveillance,Epidemiology,and End Results(SEER)*** patients were randomly allocated into a training cohort(n=15,227)and internal validation cohort(n=6,526)at a 7:3 *** the Cox regression models,significant prognostic factors were identified and used to construct 3‐,5‐,and 10‐year nomograms of OS and *** from the Molecular Taxonomy of Breast Cancer International Consortium(METABRIC)database were used as an external validation cohort(n=90).Results:We constructed nomograms incorporating 10 prognostic factors for OS and *** nomograms demonstrated strong predictive accuracy for OS and BCSS in the training cohort,with C‐indexes of 0.806 and 0.813,*** calibration curves verified that the nomograms have good prediction *** curve analysis demonstrated their practical clinical value for predicting YBC patient survival ***,we provided dynamic nomograms to improve the operability of the *** risk stratification ability assessment also showed that the OS and BCSS rates of the low‐risk group were significantly better than those of the high‐risk ***:Here,we generated and validated more comprehensive and accurate OS and BCSS nomograms than models previously developed for *** nomograms can help clinicians evaluate patient prognosis and make clinical decisions.

关键词： breast cancer‐specific survival nomogram overall survival prognostic model young breast cancer

Preparation of tungsten-particle-reinforced Zr-based bulk metallic glass composites by two-step spark plasma sintering:microstructure evolution,densification mechanism and mechanical properties

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Rare Metals 2024年第4期43卷 1793-1808页

作者： Yun-Fei Ma Pan Gong Mao Zhang Hui-EHu Zhen Peng Xiao xu Xin Wang Mehdi Malekan xue-Feng Tang Lei Deng Jun-Song Jin Xin-Yun Wang State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Research Institute of Huazhong University of Science and Technology in Shenzhen Shenzhen518057China Department of Chemistry and Materials Naval University of EngineeringWuhan430032China School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China College of Machine Shanghai Dianji UniversityShanghai201306China School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

A new two-step spark plasma sintering(TSS)process with low-temperature pre-sintering and high-temperature final sintering has been successfully applied to prepare the tungsten-particle(Wp)-reinforced bulk metallic glass composites(Wp/BMGCs).Compared to normal spark plasma sintering(NS),the densification rate and relative density of Wp/BMGCs can be improved by selecting TSS with appropriate sintering pressure in the low temperature pre-sintering ***,the compressive strength and plastic strain of 30%Wp/BMGCs prepared by TSS are both higher than those of the samples prepared by *** TSS process can significantly enhance the compressive strength of 30%Wp/BMGCs by 12%and remarkably increase the plastic strain by 50%,while the trend is completely opposite for 50%Wp/***-in situ experiments and finite element simulations reveal that uneven temperature distribution among particles during low-temperature pre-sintering causes local overheating at contact points between particles,accelerating formation of sintering neck between particles and plastic deformation of *** the volume fraction of Wp is low,TSS can improve the interface bonding between particles by increasing the number of sintering *** makes the fracture mode of Wp/BMGCs being predominantly transgranular ***,as the volume fraction of Wp increases,the adverse effects of Wp plastic deformation are becoming more and more *** aggregated Wp tends to form a solid"cage structure"that hinders the bonding between particles at the interface;correspondingly,the fracture behavior of Wp/BMGCs is mainly dominated by intergranular ***,reducing the sintering pressure during the low-temperature pre-sintering stage of TSS has been shown to effectively decrease plastic deformation in Wp,resulting in a higher degree of densification and better mechanical properties.

关键词： Bulk metallic glass composites Tungsten particle Two-step spark plasma sintering Densification mechanism Mechanical properties

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水下爆炸冲击波反射压力计算方法的改进

兵工学报 2024年第4期45卷 1196-1207页

作者：严泽臣岳松林邱艳宇王建平赵跃堂施杰李旭陆军工程大学爆炸冲击防灾减灾国家重点实验室江苏南京210007 91053部队北京100070 陆军工程大学国防工程学院江苏南京210007

重力坝是一类常见大型混凝土水工建筑。为探寻适用于其近区水下爆炸冲击波反射压力的计算方法,利用冲击波阵面上的质量、动量和能量3个守恒基本关系式,以及凝聚介质状态方程,严格推导出物理内涵明晰的刚性壁面水下爆炸冲击波反射压力计... 详细信息

重力坝是一类常见大型混凝土水工建筑。为探寻适用于其近区水下爆炸冲击波反射压力的计算方法,利用冲击波阵面上的质量、动量和能量3个守恒基本关系式,以及凝聚介质状态方程,严格推导出物理内涵明晰的刚性壁面水下爆炸冲击波反射压力计算方法。通过连续介质中冲击波速与粒子速度之间的关系,给出其中水的状态参数k的确定方法,揭示状态参数k随入射冲击波压力呈双指数衰减规律,发现入射压力在725 MPa以上时,k值的变化对冲击波反射压力计算结果有着重大影响。通过与Cole[12]、Henrych[14]和罗泽立等[15]提出的计算方法及数值仿真进行对比验证分析,结果表明:新提出的计算方法具有适用范围更广、计算精度更高的特点,且首次从理论上揭示水下爆炸冲击波反射压力系数范围为2.00~4.49。

关键词：水下爆炸反射压力刚性壁面 Hugoniot关系式数值模拟

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A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song Deng Hao-Yu Pan Hai-Ge Wang Shou-Kun xu Xiao-Peng Yan Chao-Wei Li Ming-Guo Peng Hao-Ping Peng Lin Shi Meng Cui Fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&D Company Limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress Machine learning

Polarization-dependent photoinduced metal–insulator transitions in manganites

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Science Bulletin 2024年第2期69卷 183-189页

作者： Lina Deng Weiye Zhang Hanxuan Lin Lifen Xiang Ying xu Yadi Wang Qiang Li Yinyan Zhu Xiaodong Zhou Wenbin Wang Lifeng Yin Hangwen Guo Chuanshan Tian Jian Shen State Key Laboratory of Surface Physics Institute for Nanoelectronic Devices and Quantum Computingand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Quantum Sciences Shanghai 201315China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Shanghai Branch CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum PhysicsShanghai 201315China

In correlated oxides,collaborative manipulation on light intensity,wavelength,pulse duration and polarization has yielded many exotic discoveries,such as phase transitions and novel quantum *** view of potential optoelectronic applications,tailoring long-lived static properties by light-induced effects is highly *** far,the polarization state of light has rarely been reported as a control parameter for this ***,we report polarization-dependent metal-to-insulator transition(MIT)in phaseseparated manganite thin films,introducing a new degree of freedom to control static ***,we observed giant photoinduced resistance jumps with striking features:(1)a single resistance jump occurs upon a linearly polarized light incident with a chosen polarization angle,and a second resistance jump occurs when the polarization angle changes;(2)the amplitude of the second resistance jump depends sensitively on the actual change of the polarization *** transmittance measurements reveal that the origin of the above phenomena is closely related to the coexistence of anisotropic *** results represent a first step to utilize light polarization as an active knob to manipulate static phase transitions,pointing towards new pathways for nonvolatile optoelectronic devices and sensors.

关键词： Metal-insulator phase transitions Polarization of light Electronic phase separation Selective domain controllability

Corrosion–wear behavior of a biocompatible magnesium matrix composite in simulated body fluid

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Friction 2022年第1期10卷 31-43页

作者： Jinlong SU jie TENG Zili xu Yuan LI College of Materials Science and Engineering Hunan UniversityChangsha 410082China The First Affiliated Hospital Hunan Normal UniversityChangsha 410006China

Magnesium matrix composites are a new generation of biocompatible implant materials,but they will inevitably undergo simultaneous wear and corrosion in the human *** this study,hydroxyapatite(Ca10(PO4)6(OH)2,HA)is used in a magnesium matrix composite to study its effects on the corrosion–wear *** samples(a magnesium alloy composed of Mg,Zn,and Zr(ZK60)alloy and ZK60/10HA composite)were fabricated using the powder metallurgy(PM)*** corrosion–wear behavior was investigated using the sliding wear test in a simulated body fluid(SBF).At all the sliding velocities tested,the corrosion–wear resistance of ZK60/10HA was superior to *** a sliding velocity of 942.5 mm/min,ZK60/10HA demonstrated a 42%improvement in corrosion–wear resistance compared to *** ZK60,the main wear mechanism under dry conditions was abrasion,while the wear mechanisms in the SBF were abrasion and *** ZK60/10HA,the wear mechanisms under dry conditions were abrasion and delamination,while in SBF they were mainly abrasion and corrosion,accompanied by slight *** results indicated that HA particles can be used as an effective corrosion–wear inhibitor in biocompatible magnesium matrix composites.

关键词： wear corrosion alloy

Multiplicative Integral Theory of Generalized Orthopair Fuzzy Sets and Its Applications

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Journal of Systems Science and Systems Engineering 2022年第4期31卷 457-479页

作者： jie Gao Zeshui xu Chao Zhong Yunshu Mao School of Business Administration Southwestern University of Finance and EconomicsChengdu610207China Business School Sichuan UniversityChengdu610064China

There are two main issues of fuzzy multi-attribute decision-making:determine the weight of each attribute and choose an appropriate aggregation method to integrate the evaluation information of different *** order to solve the multi-attribute decision-making problem in generalized orthopair fuzzy environment with unknown attribute weights more effectively,we give a decision-making method based on generalized orthopair fuzzy definite *** be specific,we first introduce the complement operations of q-rung orthopair fuzzy numbers,and then investigate the multiplicative q-rung orthopair fuzzy *** the complement operations,we establish the mutual conversion formula between additive and multiplicative q-rung orthopair fuzzy calculus ***,we give a multiplicative integral-based q-rung orthopair fuzzy multi-attribute decision-making method,and discuss the relationship between the q-rung orthopair fuzzy definite integrals and the q-rung orthopair fuzzy weighted geometric *** with traditional decision-making methods,this method does not rely on subjective weight information,which is especially important when dealing with large sample ***,the application of election is studied to verify the feasibility and effectiveness of the proposed *** the introduction of generalized orthopair fuzzy sets,the expression form of election evaluation information has been *** also provide some examples to compare the obtained results with the results generated by the addition operation and reveal the correlation between them.

关键词： Fuzzy sets decision making aggregation operators

Role of Residue 90 in Catalysis of Cytochrome P450 2C9

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Chemical Research in Chinese Universities 2009年第6期25卷 904-908页

作者： WANG Ying ZHOU Yi-han GUO Ying-jie xu xue-lian si Da-yong ZHOU Hui LI Ze-sheng College of Life Science State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China

The cytochrome P450 mutant CYP2C9.13（L90P） shows a greatly impaired catalytic activity compared with the wild-type. We constructed the mutants by substitution at residue 90 of CYP2C9, expressed in COS-7 cells, assayed their thermal stability and catalysis activity and analyzed the mutants via molecular dynamic（MD） simulation and flexible docking. Mutant L90E exhibits a significantly lower catalytic activity than the wild-type for the hydroxylation of diclofenac, lornoxicam and luciferin and its molecular dynamics simulation results indicate that the size of the entrance of substrate access was reduced significantly. An increase or minor decrease of catalytic activity was observed for mutants L90Q, L90W, L90R, L90I and L90G, and the sizes of the entrances of substrate access and the active site cavities had a little change in those mutants. The thermal stability and the potential energy of the MD simulation of these mutants showed a similar tendency as the catalysis assays did. Flexible docking results show the fluctuation of interaction energy is due to the change of electrostatic potential distribution. All the above facts show that the changes in the catalysis activity of the mutants caused by the substitution at residue 90 are due to the changes in the size of entrance, the shape and size of active site cavity, electrostatic potential distribution and thermal stability. The residue 90 of CYP2C9 has an important effect on the enzyme catalytic activity.

关键词： CYP2C9 Mutation Molecular dynamics(MD) Flexible docking Catalytic activity