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The water content and hydrogen isotope composition of continental lithospheric mantle and mantle-derived mafic igneous rocks in eastern China

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Science China Earth Sciences 2016年第5期59卷 910-926页

作者： XU Zheng gong bin ZHAO ZiFu Chinese Academy of Sciences Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of China

The water contents of minerals and whole-rock in mantle-derived xenoliths from eastern China exhibit large variations and are generally lower than those from other on- and off-craton lithotectonic units. Nevertheless, the water contents of mineral and whole-rock in Junan peridotite xenoliths, which sourced from the juvenile lithospheric mantle, are generally higher than those elsewhere in eastern China. This suggests that the initial water content of juvenile lithospheric mantle is not low. There is no obvious correlation between the water contents and Mg~# values of minerals in the mantle xenoliths and no occurrence of diffusion profile in pyroxene, suggesting no relationship between the low water content of mantle xenolith and the diffusion loss of water during xenolith ascent with host basaltic magmas. If the subcontinental lithospheric mantle（SCLM） base is heated by the asthenospheric mantle, the diffusion loss of water is expected to occur. On the other hand, extraction of basaltic melts from the SCLM is a more efficient mechanism to reduce the water content of xenoliths. The primary melts of Mesozoic and Cenozoic basalts in eastern China have water contents, as calculated from the water contents of phenocrysts, higher than those of normal mid-ocean ridge basalts（MORB）. The Mesozoic basalts exhibit similar water contents to those of island arc basalts, whereas the Cenozoic basalts exhibit comparable water contents to oceanic island basalts and backarc basin basalts with some of them resembling island arc basalts. These observations suggest the water enrichment in the mantle source of continental basalts due to metasomatism by aqueous fluids and hydrous melts derived from dehydration and melting of deeply subducted crust. Mantle-derived megacrysts, minerals in xenoliths and phenocrysts in basalts from eastern China also exhibit largely variable hydrogen isotope compositions, indicating a large isotopic heterogeneity for the Cenozoic SCLM in eastern China. The wa

关键词： Eastern China Continental basalt Lithospheric mantle Water Hydrogen isotope

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Pressure Control of a Large-scale Hydraulic Power Unit Using π Bridge Network

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 386-391页

作者： FENG bin gong Guofang YANG Huayong The State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The steady state and dynamic characteristics of pressure output of a hydraulic power unit are important to the hydraulic system *** of the compact structure,the B-half bridge resistance network is widely used in the pilot controlled pressure relief *** the steady-state pressure error might be unacceptably big in those pressure control systems.A constant pressure power unit is typically assumed in analysis of steady state and dynamic behavior of hydraulic *** flow-pressure relationship seems to be much complex,in particular when big flow variation takes *** this paper,the π bridge hydraulic resistance network pilot stage is designed in order to get better flow-pressure *** on the similarity of electrical circuits,the main factors influencing flow-pressure characteristics are ***,the optimum diameters of both constant hydraulic resistor and dynamic resistor are ***-pressure characteristics are compared with different constant hydraulic resistors,dynamic resistor and spring stiffness by simulations and *** of simulations and experiments show that flow-pressure characteristics depend very little on the spring stiffness in whole flow *** controlled pressure characteristics can be achieved with suitable constant *** can be reduced with the small diameter of the dynamic ***-pressure characteristics of pressure relief valve can be improved with a π bridge pilot *** proposed pressure control method will provide some positive guidelines and be helpful to design a high performance hydraulic system with large flow.

关键词： two stage pressure relief valve π bridge resistor network flow-pressure characteristics

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Data-Driven Model Falsification and Uncertainty Quantification for Fractured Reservoirs

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Engineering 2022年第11期18卷 116-128页

作者： Junling Fang bin gong Jef Caers School of Earth Resources China University of GeosciencesWuhan 430074China Key Laboratory of Tectonics and Petroleum Resources of the Ministry of Education Wuhan 430074China Department of Geological Sciences Stanford UniversityStanford 94305USA

Many properties of natural fractures are uncertain,such as their spatial distribution,petrophysical properties,and fluid flow *** theorem provides a framework to quantify the uncertainty in geological modeling and flow simulation,and hence to support reservoir performance *** application of Bayesian methods to fractured reservoirs has mostly been limited to synthetic *** field applications,however,one of the main problems is that the Bayesian prior is falsified,because it fails to predict past reservoir production *** this paper,we show how a global sensitivity analysis(GSA)can be used to identify why the prior is *** then employ an approximate Bayesian computation(ABC)method combined with a tree-based surrogate model to match the production *** apply these two approaches to a complex fractured oil and gas reservoir where all uncertainties are jointly considered,including the petrophysical properties,rock physics properties,fluid properties,discrete fracture parameters,and dynamics of pressure and *** successfully identify several reasons for the *** results show that the methods we propose are effective in quantifying uncertainty in the modeling and flow simulation of a fractured *** uncertainties of key parameters,such as fracture aperture and fault conductivity,are reduced.

关键词： Bayesian evidential learning Falsification Fractured reservoir Random forest Approximate Bayesian computation

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New approach for amplitudes with multiple fermion lines

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Chinese Physics C 2022年第8期46卷 63-71页

作者： Feng Zhang bin gong Jian-Xiong Wang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China

A new approach for tree-level amplitudes with multiple fermion lines is *** primarily focuses on the simplification of fermion *** calculating two vectors recursively without any matrix multiplications,the result of a fermion line is reduced to a very compact form depending only on the two *** with other packages are presented,and the results show that our package FDC provides a very good performance in the processes of multiple fermion lines with this new approach and some other improvements.A further comparison with WHIZARD shows that this new approach has a competitive efficiency in computing pure amplitude squares without phase space integration.

关键词： multi-particle process scattering amplitude fermion line tree level

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Discontinuous deformation and displacement analysis: From continuous to discontinuous

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Science China(Technological Sciences) 2015年第9期58卷 1567-1574页

作者： TANG ChunAn TANG Shibin gong bin BAI HongMei State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian Mechsoft Co. Ltd.

A discontinuous deformation and displacement(DDD) analysis method is proposed for modelling the rock failure process. This method combines the rock failure process analysis(RFPA) method(based on finite element method) and discontinuous deformation analysis(DDA) method. RFPA is used to simulate crack initiation, propagation and coalescence processes of rock during the small deformation state. The DDA method is used to simulate the movement of blocks created by the multiple cracks modelled by the RFPA. The newly developed DDD method is particularly suitable for modelling both crack propagation and block movement during the rock failure process because of the natural and convenient coupling of continuous and discontinuous deformation analyses. The proposed method has been used to simulate crack initiation, propagation and coalescence within a slope as well as the block movement during the landslide process. Numerical modelling results indicate that the proposed DDD method can automatically simulate crack propagation and block movement during the rock failure process without degrading accuracy.

关键词： rock failure process finite element method discontinuous deformation analysis (DDA) crack propagation slope stability

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Existence of Weakly Cooperative Equilibria for Infinite-Leader-Infinite-Follower Games

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Journal of the Operations Research Society of China 2019年第4期7卷 643-654页

作者： Zhe Yang Qing-bin gong School of Economics Shanghai University of Finance and EconomicsShanghai 200433China SUFE Key Laboratory of Mathematical Economics Ministry of EducationShanghai 200433China

In this paper,we first generalize Yang and Ju’s(J Glob Optim 65:563–573,2016)result in Hausdorff topological vector ***,we introduce the model of leader-follower games with infinitely many leaders and followers,that is,infiniteleader-infinite-follower *** next introduce the notion of weakly cooperative equilibria for infinite-leader-infinite-follower games and prove the existence result.

关键词： (Weakly)cooperative equilibrium Infinite-leader-infinite-follower game Existence

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THE DISCRETE DYNAMICS FOR COMPETITIVE POPULATIONS OF LOTKA-VOLTERRA TYPE

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Applied Mathematics(A Journal of Chinese Universities) 1995年第4期10卷 419-426页

作者： LIU LAIFU AND gong bin Department of Mathematics Beijing Normal University Beijing

The discrete dynamics for competition populations of Lotka-Volterra type modeled as N1(t+1)=N1(t) exp[r1(1-N1-b12N2)], N2(t+1)=N2(t) exp[r2(1-N2-b21N1)] is considered in the paper. In the case of non-persistence the attractive behavior of model has been discussed. Especially, there are two attractive sets when h_(ij)>1, and the attractive behaviors are more complicated than that of the corresponding cofitinuous model. The attracted regions are given. We prove that the model is also persistent in the degenerate case of b_(ij)=1. In the persistence case of b_(ij)<1, the existence and uniqueness for two-period points of the model are studied at r1=r2. The condition for the multi-pair of two-period points is indicated and their influences on population dynamical behaviors are shown.

关键词： Competition model non-linear discrete dynamics attractive behavior persistence,two-period point.

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Confident Estimation for Density of a Biological Population Based on Line Transect Sampling

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 79-92页

作者： Ren-bin gong Yun-bei Ma Yong Zhou Research Institute of Petroleum Exploration and Development Northwest Gansu 730020 China Academy of Mathematics and System Science. Chinese Academy of Science Beijing 100190 China Department of Statistics Shanghai University of Finance and Economics Shanghai 200433 China

Line transect sampling is a very useful method in survey of wildlife population. Confident interval estimation for density D of a biological population is proposed based on a sequential design. The survey area is occupied by the population whose size is unknown. A stopping rule is proposed by a kernel-based estimator of density function of the perpendicular data at a distance. With this stopping rule, we construct several confidence intervals for D by difference procedures. Some bias reduction techniques are used to modify the confidence intervals. These intervals provide the desired coverage probability as the bandwidth in the stopping rule approaches zero. A simulation study is also given to illustrate the performance of this proposed sequential kernel procedure.

关键词： Line transect sampling Confident interval estimation Stopping rule Bias reduction

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Partial Oxidation of Toluene on VO_x-TiO_x/SBA-15

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Chemical Research in Chinese Universities 2009年第6期25卷 924-928页

作者： FANG Ke-gong WANG bin SUN Yu-han State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 P. R. China

A series of VOx-TiOx/SBA-15 catalysts was rized by different techniques such as N2-sorption, TPR prepared by the grafting method. The catalysts were characte- UV-Vis and NH3-TPD in order to verify the vanadium and titanium species, and their catalytic properties were investigated for the partial oxidation of toluene. The results show that vanadium mainly existed in the forms of isolated tetrahedral and octahedral species at the low loadings. The introduction of a certain amount of titanium improved the dispersion of vanadium on the support and then the catalytic performance for toluene oxidation at the same vanadium content. Both toluene conversion and benzaldehyde selectivity, showed the maximum values and then decreased with increasing the amount of titanium in the catalyst.

关键词： Vanadium Titanium Partial oxidation Toluene Benzaldehyde

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Formation process of cover collapse sinkholes related to groundwater level decline in karst areas

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Journal of Mountain Science 2024年第11期21卷 3832-3846页

作者： LIU Xingzong CHEN Hongkai gong bin JIANG Guanghui WANG Jintao School of Civil Engineering Ludong UniversityYantai 264025China School of Geographical Sciences China West Normal UniversityNanchong 637001China College of Engineering Design and Physical SciencesBrunel University LondonLondon UB83PHUK

The decline in groundwater level is a key factor contributing to cover collapse in karst *** this study,the model tests and numerical simulations are conducted to reveal the breeding process and formation mechanism of cover collapse sinkholes caused by the decline of groundwater level in karst ***,the model tests confirm that the decline of groundwater level generates negative pressure at the lower edge of overlying *** negative pressure experiences four distinct phases during the groundwater drawdown process:rapid rise,slow decline,rapid decline,and gradual *** maximum negative pressure is influenced by the particle size distribution of the overlying ***,the numerical simulations are carried out to investigate the change process of negative pressure caused by the loss of fillers in karst *** simulated results indicate that the rate of groundwater decline and the thickness and initial void ratio of the overlying soil can affect the maximum negative *** groundwater level drops,a negative pressure zone forms underground,causing tensile failure in the surrounding soil and creating an arched soil hole,which weakens the support for the overlying *** phenomenon can also lead to the collapse of the overlying soil under its *** table decline in karst areas can result in both internal and surface *** the overlying soil is thin,internal and surface collapses occur *** contrast,for thick overlying soil,internal collapse happens first,followed by a layer-by-layer collapse,ultimately forming ***,the breeding process and formation mechanism of the Yujiawan Reservoir sinkholes are *** conditions and groundwater level decline significantly affect internal collapse in karst areas,requiring careful consideration from on-site engineers.

关键词： Cover collapse sinkhole Groundwater level decline Karst area Model test Numerical simulation

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