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Chinese Science Bulletin 2004年第17期49卷 1834-1840页

作者： FANGKe LIYingxia liuhua LIAOWeijing LEIHao StateKeyLaboratoryofMagneticResonanceandAtomicandMolecularPhysics WuhanInstituteofPhysicsandMathematicsChineseAcademyofSciencesWuhan430071China ZhongnanHospitalofWuhanUniversity Wuhan430071China

Manganese enhanced magnetic resonance im- aging (MRI) is a novel neuroimaging technique that can be used in vivo to trace neuronal tract and to study brain func- tions dynamically. In this study, manganese enhanced MRI was used to trace the neuronal tracts between the laminar structures of the olfactory bulb (OB) in rat and to study the so-called “calcium overload” phenomenon in a rat model of cerebral ischemia. High spatial resolution images of the OB were obtained and used to measure the transportation rate of Mn2+ among the laminar structures of the OB, which was shown to be approximately 0.2 mm/h under resting condition. In the rat focal ischemia study, it was found that the total area of brain regions with Mn2+ accumulation (representing brain regions with calcium overload) was only 55%±15% of the area of the ischemic brain regions shown by diffu- sion-weighted imaging (DWI). Manganese enhanced MRI might be more accurate than DWI in detecting the ischemic core at the early stage of experimental cerebral ischemia.

关键词： MRI 神经元局部缺血脑缺血锰离子钙离子嗅球磁响应图像

NUMERICAL SIMULATION OF BED TOPOGRAPHY CHANGES INDUCED BY DEEP WATER NAVIGATION CHANNEL PROJECT IN THE YANGTZE ESTUARY

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Journal of Hydrodynamics 2003年第4期15卷 46-53页

作者： ZhangJing-xin liuhua HeYou-sheng ZhangFu-ran QiDing-man SchoolofCivilEngineeringandMechanics ShanghaiJiaotongUniversityShanghai200030China ResearchCenterofEstuarineandCoastalSciences Shanghai201201China

A study on the mathematical modeling of the two dimensional, time-dependentvariation of bottom topography caused by the spur dikes of the deep water navigation channel projectin the Yangtze estuary is reported. The hydro-dynamic flows are computed using the DELFT3D whichserves as the base of computation of sediment transport and bottom deformation. A model of finesediment transport is developed and implemented in an orthogonal curvilinear coordinate system bythe finite difference method. Using the observed water depth of the North Channel of Yangtze estuaryfrom 2001 to 2002, the model is calibrated and validated to determine the parameters in thesediment model. The computational results of the changes of the bed in the North Channel induced bythe spur dikes coincide with the measured data except the area near the structures.

关键词： tidal flow sediment transport yangtze estuary mathematical model

Surface decomposition and annealing behavior of GaN implanted with Eu

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Nuclear Science and Techniques 2002年第3期13卷 167-171页

作者： liuhua－Ming ZHANGZhi－Bin 等 LaboratoryofNuclearAnalysesandTechniques ShanghaiInstituteofNuclearResearchtheChineseAcademyofSciencsShanghai201800 LaboratoryofNuclearAnalysesandTechniques ShanghaiInstituteofNuclearResearchtheChi

Investigations on surface decomposition of GaN implanted with low energy (80 keV) Eu ion to a low dose (l×1014 cm-2), and its annealing behavior under high temperature (1050℃) in N2 are performed. The as-grown, as-implanted and annealed GaN films are characterized by proton elastic scattering (PES), Rutherford backscattering spectrometry (RBS), photoluminescence (PL) and atomic force microscopy (AFM). The results show that Eu ion implantation induces radiation defects and decomposition of GaN. The GaN surface decomposition is more serious during high temperature annealing. The atomic ratio of N in as-grown, as-implanted and annealed GaN film is 47 at.%, 44 at.% and 40 at.%, respectively. As a result, a rough Ga-rich layer is formed at the surface, though the lattice defects are partly removed after high temperature annealing.

关键词：半导体材料 GaN 退火行为表面离解

Dynamic traffic grooming in distributed-controlled IP／WDM optical mesh networks

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High Technology Letters 2005年第2期11卷 146-151页

作者：黄俊 ZengQingji LiuJimin XiaoPengcheng liuhua XiaoShilin CenterforBroadbandOpticalNetworkingTechnology ShanghaiJiaotongUniv.Shanghai200030P.R.China

In this paper, the study was devoted to the traffic-grooming problem in a distributed-controlled WDM mesh network. We studied the optimization of the maximal number of ports configured at each node in the network. We gave the maximumnumber simulation results in different network environment, which could be taken as a reference for network design.

关键词： WDM 波长分割多路技术光学网络计算机网络通信管理分布式控制

Effect of strain on charge density wave order inα-U

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Chinese Physics B 2022年第6期31卷 643-649页

作者： liuhua Xie Hongkuan Yuan Ruizhi Qiu School of Physical Science and Technology Southwest UniversityChongqing 400715China Institute of Materials China Academy of Engineering PhysicsMianyang 621907China

The effect of strain on charge density wave(CDW)order inα-U is investigated within the framework of relativistic density-functional *** energetical stability ofα-U with CDW distortion is enhanced by the tensile strain along a and b axes,which is similar to the case of negative pressure and ***,the tensile strain along c axis suppresses the energetical stability of CDW *** abnormal effect could be understood from the emergence of a new onedimensional atomic chain along c axis inα-***,this effect is supported by the calculations of Fermi surface and phonon mode,in which the topological objects and the dynamical instability show opposite behaviors between strains along a/b and c axes.

关键词： uranium charge density wave strain effect density-functional theory

Dynamic Changes of the Farmers and Herdsmen’s Income Sources in the Tibet Autonomous Region

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Wuhan University Journal of Natural Sciences 2005年第4期10卷 745-750页

作者： LIXiang-mei liuhua PENGChuan-zhong ZHONGXiang-hao StateKeyLaboratoryofPollutionControlandResourceReuse Nanjing210093JiangsuChina XinjiangInstituteofEcologyandGeography ChineseAcademyofSciencesUrumqi830011XinjiangChina InstituteofMountainHazardsandEnvironment ChineseAcademyofSciencesChengdu610041SichuanChina

Based on the Tibet Autonomous Region's statistic yearbooks and the data fromthe two household surveys in 2002 and 2004, this paper has comprehensively analyzed the pattern ofchanges on the farmers and herdsmen's income sources in the Tibet Autonomous Region since 1990 withthe main findings as follows; (1) The change of income from the labor payment is the fastest; (2)There is no regular pattern of income variation for the household economic activities, the farmersand herdsmen's household incomegeneration projects are impacted by the elements like prices andreturns, and there is a lack of appropriate direction; (3) The income structure of labor paymentshows that the income from the farmers and herdsmen working outside grows fastest; (4) The incomefrom the farmers and herdsmen's labor payment correlate positively to their net income per capita;(5) From the perspective of the variation by region, labor payment income has changed fastest in thecounties of Rutok, Nyerong and Khangmar comparedthe data from the household survey in 2002 withthat of 2004.

关键词： the Tibet Autonomous Region rural residents income source

Study on Strength Reduction Law and Meso-Crack Evolution of Lower Layered Cemented Tailings Backfill

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Journal of Renewable Materials 2023年第3期11卷 1513-1529页

作者： Huazhe Jiao Wenxiang Zhang Yunfei Wang Xinming Chen liuhua Yang Yangyang Rong State Collaborative Innovation Center of Coal Work Safety and Clean-Efficiency Utilization School of Civil EngineeringHenan Polytechnic UniversityJiaozuo454003China Provincial Key Laboratory of Underground Engineering and Disaster Prevention and Control School of Civil EngineeringHenan Polytechnic UniversityJiaozuo454003China School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

The green disposal of tailings solid waste is a problem to be solved in mine *** tailings filling stoping method can realize the dual goals of solid waste resource utilization and mined-out area ***,the volume of the mined-out area of the open-pit method is larger than the filling capacity,resulting in the complex stratification of the underground backfill,and the strength of the backfill cannot meet the *** this paper,according to the delamination situation,the specimens of horizontal and inclination angle layered cemented tailings backfill(LCTB)is made for a uniaxial compression test,and the failure process of delamination backfill is reduced by *** results show that the corresponding reduction factorφof horizontal LCTB is 0.560–0.932,and the correspondingφvalue of inclination angle LCTB is 0.338–*** failure mode of backfill in different layers is mainly manifested as a tensile *** PFC numerical simulation results are consistent with laboratory test results,which verifies the correctness of backfill *** research results provide a reliable theoretical basis for the strength design of backfill in goaf,which is of great significance for solid waste utilization and environmental protection.

关键词： Solid wastes recycling LCTB uniaxial compression strength reduction granular flow

Particle aggregation and breakage kinetics in cemented paste backfill

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 1965-1974页

作者： liuhua Yang Hengwei Jia Aixiang Wu Huazhe Jiao Xinming Chen Yunpeng Kou Mengmeng Dong School of Civil and Engineering Henan Polytechnic UniversityJiaozuo 454000China School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

The macroscopic flow behavior and rheological properties of cemented paste backfill(CPB)are highly impacted by the inherent structure of the paste *** this study,the effects of shear-induced forces and proportioning parameters on the microstructure of fresh CPB were *** size evolution and distribution of floc/agglomerate/particles of paste were monitored by focused beam reflection measuring(FBRM)technique,and the influencing factors of aggregation and breakage kinetics of CPB were *** results indicate that influenced by both internal and external factors,the paste kinetics evolution covers the dynamic phase and the stable *** the mass content or the cement-tailings ratio can accelerate aggregation kinetics,which is advantageous for the rise of average floc ***,the admixture and high shear can improve breaking kinetics,which is beneficial to reduce the average floc *** chord length resembles a normal distribution somewhat,with a peak value of approximate 20μ*** particle disaggregation con-stant(k_(2))is positively correlated with the agitation rate,and k_(2) is five orders of magnitude greater than the particle aggregation constant(k1).The kinetics model depicts the evolution law of particles over time quantitatively and provides a theoretical foundation for the micromechanics of complicated rheological behavior of paste.

关键词： cemented paste backfill particle kinetics admixture rheology

Correlative Mechanism of Hydraulic-mechanical Property in Cemented Paste Backfill

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Journal of Wuhan University of Technology(Materials Science) 2017年第3期32卷 579-585页

作者：王勇吴爱祥 WANG Shaoyong WANG Hongjiang YANG liuhua WANG Yiming RUAN Zhu'en Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology Beijing Beijing 100083 China School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Xuzhou 221116 China

Hydraulic characteristic is a good indication of binder hydration, which determines the strength development of cemented paste backfill（CPB）. Therefore, the hydraulic characteristic should be communicated with the mechanical property to provide an advanced knowledge that can help mine workers make a rational strategy and reduce the mining cycle. An experimental program was performed to obtain the hydraulic（monitored by suction and volumetric water content） and mechanical properties（unconfined compressive strength（UCS） test） of CPB at the 28 days curing age. According to the monitoring and testing results, the relationships between the hydration reaction rate and volumetric water content（VWC）, suction and VWC, suction and UCS were established. The hydration degree showed a liner rise as the VWC decreased. Curves of the VWC and UCS were featured with a nonlinear reduction and nonlinear growth（both are exponential functions） as the suction rising, respectively. These established relationships validated the strong correlative mechanism of hydraulic and mechanics behavior for CPB. Also, the results of the present research indicated that the hydraulic characteristics and mechanical property were strongly coupled. These correlations and couplings will be of great importance to understand the hardening process of CPB and bring to a safe CPB field operation.

关键词： cemented paste backfill mine hydraulic volumetric water content suction strength

Systematic review of mixing technology for recycling waste tailings as cemented paste backfill in mines in China

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International Journal of Minerals,Metallurgy and Materials 2023年第8期30卷 1430-1443页

作者： liuhua Yang Jincang Li Hongbin Liu Huazhe Jiao Shenghua Yin Xinming Chen Yang Yu School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China Department of Civil Engineering University of Ottawa161 Colonel By DriveOttawaONK1N 6N5Canada School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuo454000China China Geological Environmental Monitoring Institute Beijing100081China

The development of industry is inseparable from the support of ***,mining processes consume a large amount of energy,and increased tailing emissions can have a significant impact on the *** the past few decades,the mining industry developed many technologies that are related to mineral energy management,of which cemented paste backfill(CPB)is one of the representative *** has been successfully applied to mine ground control and tailings *** CPB technology,the mixing process is the key to achieving materials with good final quality and controlled ***,in the preparation process,the mixed homogeneity of the CPB is difficult to achieve because of fine tailings,high solid volume fraction,and high *** research focused on the effect of mixing ingredients on CPB properties rather than on the preparation process of the ***,improving the performance and reducing the production cost of CPB by optimizing the mixing process are *** review summarizes the current studies on the mixing technology of CPB and its application status in ***,it compares the advantages and disadvantages of multiple mixing equipment and discusses the latest results and research hotspots in paste ***,it concludes the challenges and development trends of mixing technology on the basis of the relevant application cases in China to promoting cement-based material mixing technology development.

关键词： cemented paste backfill mixed homogeneity mixing technology cement-based material