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Estimation of mountain block recharge on the northern Tianshan Mountains using numerical modeling

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Journal of Mountain Science 2021年第7期18卷 1794-1810页

作者： ping jian-hua ZHU Ya-qiang MEI Xue-mei LENG Wei LI sheng ZHAO ji-chang College of Earth Science and Technology Zhengzhou UniversityZhengzhou 450001China School of Water Conservancy Engineering Zhengzhou UniversityZhengzhou 450001China College of Geology and Exploration Engineering Xinjiang UniversityUrumqi 830047China China Institute of Geo-Environmental Monitoring Beijing 100081China

Mountain block recharge(MBR),an important water resource,is a widespread process that recharges lowland ***,little is known about MBR due to the limited climatic and geologic data in mountainous regions such as the northern central foothills of ***,we present an approach to quantify MBR through the combination of water balance calculations and numerical *** calculated from the water balance in the data-limited Tianshan Mountains is employed as a fluid-flux boundary condition in the numerical model of the *** verify the performance of the model,mean absolute error and root mean square error were *** show that the volume of water that is recharging the aquifer via MBR is 107.29 million m^(3)/yr,accounting for 2.2% of the total precipitation that falls in the ***,53.3% of that precipitation enters the plain aquifer via runoff,totaling 2,652.68 million m^(3)/*** lower volume of MBR is attributed to a major range-bounding anticline with apparent low permeability in the Tianshan *** numerical modeling of groundwater,MBR coming from bedrock was found to be significant,accounting for 14% of total aquifer recharge in the plain,only after the portion of runoff *** research contributes to a deeper understanding of MBR,and may provide instructions for estimating groundwater recharge in arid and semi-arid areas.

关键词： Mountain block recharge Water balance Numerical modeling Arid area Tianshan Mountains

Reduction of shrinkage porosities in aluminum alloy castings by external pressure fluctuation under gravity field

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China Foundry 2018年第5期15卷 372-377页

作者： Shi-ping Wu Ru-jia Wang Ye Wang Wei Chen Ze-sheng ji School of Materials Science and Engineering Harbin Institute of Technology School of Materials Science and Engineering Harbin University of Science and Technology

A novel method to improve the feeding capacity of ZL205 A alloy castings by pressure fluctuation during its solidification process under gravity field was proposed. The experiments were done in the graphite mould by applying the fluctuation pressure at the top of the riser. Results of the X-ray inspection of castings and simulations of flow velocity of alloy melt and temperature field show that the new method can effectively improve the feeding capacity and significantly reduce the shrinkage in the castings. The mechanism of improving the feeding capacity by pressure fluctuation is that the fluctuating pressure can make the ZL205 A alloy melt form a vibration wave in the melt. The vibration wave can intensify the convection of the melt, and therefore, break down the barrage from the feeding channel which forms during the solidification process of the ZL205 A alloy, improving the feeding capacity.

关键词： Fluctuation pressure shrinkage porosity ZL205A alloy gravity casting

Resting Study of Tracer Experiment on Catalytic Wet Oxidation Reactor under Micro-gravity and Earth Gravity Conditions

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Chemical Research in Chinese Universities 2005年第6期21卷 702-706页

作者： YANG ji jiA jin-ping School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 P. R. China

The International Space Station（ISS） employs catalytic wet oxidation carried out in a Volatile Reactor Assembly （VRA） for water recycling. Previous earth gravity experiments show that the VRA is very effective at removing polar, low molecular weight organics. To compare the reactor performance under micro-gravity and Earth gravity conditions, a tracer study was performed on a space shuttle in 1999 by using 0.2% potassium carbonate as the chemical tracer. In this paper, the experimental data were analyzed and it is indicated that the reactor can be considered as a plug flow one under both micro-gravity and earth gravity experimental conditions. It has also been proved that dispersion is not important in the VRA reactor under the experimental conditions. Tracer retardation was observed in the experiments and it is most likely caused by catalyst adsorption. It is concluded that the following reasons may also have influence on the retardation of mean residence time ：（1） the liquid can be held by appurtenances, which will retard the mean residence time; （2） the pores can hold the tracer, which can also retard the mean residence time.

关键词： Tracer study Micro-gravity Dispersion model Tank in series model Catalytic wet oxidation

Topological r-entropy and Measure Theoretic r-entropy of Flows

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Acta Mathematica Sinica,English Series 2022年第4期38卷 761-769页

作者： Yong ji Yun ping WANG Department of Mathematics Ningbo UniversityNingbo 315211P.R.China School of Science Ningbo University of TechnologyNingbo 315211P.R.China School of Mathematical Sciences and Institute of Mathematics Nanjing Normal UniversityNanjing 210023P.R.China

The topological r-entropy and measure theoretic r-entropy of a flow are *** a flow(X,φ),it is shown that topological(measure theoretic)r-entropy is equal to the topological(measure theoretic)entropy of the time one ... 详细信息

关键词： Topological r-entropy measure theoretic r-entropy flow

THE ELLIPTIC TYPE NODE CONFIGURATION AND INTERPOLATION IN R^2

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Journal of Computational Mathematics 1998年第3期16卷 257-266页

作者： ping Zhu (ji’an Teachers College, ji’an 543009, jiangxi, China) 吉安师范专科学校江西吉安 343009

In this paper, we have obtained an expression of the bivariate Vandermonde determinant for the Elliptic Type Node Configuration in R-2, and discussed the possibility of the corresponding multivariate Lagrange, Hermite... 详细信息

关键词： multivariate interpolation polynomial interpolation Birkhoff interpolation node configuration

Spastin interacts with collapsin response mediator protein 3 to regulate neurite growth and branching

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Neural Regeneration Research 2021年第12期16卷 2549-2556页

作者： Zhi-sheng ji jian-ping Li Chao-Hua Fu jian-Xian Luo Hua Yang Guo-Wei Zhang Wutian Wu Hong-sheng Lin Department of Orthopedics The First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina Guangdong-Hong Kong-Macao Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina Department of Orthopedics Jiangmen Hospital of Sun Yat-sen UniversityJiangmenGuangdong ProvinceChina Re-Stem Biotechnology Co. Ltd.SuzhouJiangsu ProvinceChina Spine Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Cytoskeletal microtubule rearrangement and movement are crucial in the repair of spinal cord *** plays an important role in the regulation of microtubule *** spastin and collapsin response mediator proteins can regulate neurite growth and branching;however,whether spastin interacts with collapsin response mediator protein 3(CRMP3)during this process remains unclear,as is the mechanism by which CRMP3 participates in the repair of spinal cord *** this study,we used a proteomics approach to identify key proteins associated with spinal cord injury *** then employed liquid chromatography-mass spectrometry to identify proteins that were able to interact with glutathione ***,co-immunoprecipitation and staining approaches were used to evaluate potential interactions between spastin and ***,we co-transfected primary hippocampal neurons with CRMP3 and spastin to evaluate their role in neurite *** spectrometry identified the role of CRMP3 in the spinal cord injury repair *** chromatography-mass spectrometry pulldown assays identified three CRMP3 peptides that were able to interact with ***3 and spastin were co-expressed in the spinal cord and were able to interact with one another in vitro and in ***,CRMP3 overexpression was able to enhance the ability of spastin to promote neurite growth and ***,our results confirm that spastin and CRMP3 play roles in spinal cord injury repair by regulating neurite growth and *** proteins may therefore be novel targets for spinal cord injury *** Institutional Animal Care and Use Committee of jinan University,China approved this study(approval ***-20181008-03)on October 8,2018.

关键词： collapsin response mediator protein 3 liquid chromatography-mass spectrometry microtubule neurite growth protein interactions proteomics spastin spinal cord injury

A UNIFIED A POSTERIORI ERROR ANALYSIS FOR DISCONTINUOUS GALERKIN APPROXIMATIONS OF REACTIVE TRANSPORT EQUATIONS

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Journal of Computational Mathematics 2006年第3期24卷 425-434页

作者： ji-ming Yang Yan-ping Chen Hunan Key Laboratory for Computation and Simulation in Science and Engineering Institute for Computational and Applied Mathematics and School of Mathematics and Computing Science Xiangtan University Xiangtan 4 11105 China

Four primal discontinuous Galerkin methods are applied to solve reactive transport problems, namely, Oden-BabuSka-Baumann DG （OBB-DG）, non-symmetric interior penalty Galerkin （NIPG）, symmetric interior penalty Galerkin （SIPG）, and incomplete interior penalty Galerkin （IIPG）. A unified a posteriori residual-type error estimation is derived explicitly for these methods. From the computed solution and given data, explicit estimators can be computed efficiently and directly, which can be used as error indicators for adaptation. Unlike in the reference [10], we obtain the error estimators in L^2 （L^2） norm by using duality techniques instead of in L^2（H^1） norm.

关键词： A posteriori error estimates Duality techniques Discontinuous Galerkin methods

DYNAMIC ADVANCED PLANNING AND SCHEDULING WITH FROZEN INTERVAL FOR NEW ORDERS

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Chinese Journal of Mechanical Engineering 2007年第4期20卷 117-119页

作者： CHEN Kejia ji ping Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China

A dynamic advanced planning and scheduling （DAPS） problem is addressed where new orders arrive on a continuous basis. A periodic policy with frozen interval is adopted to increase stability on the shop floor. A genetic algorithm is developed to find a schedule at each rescheduling point for both original orders and new orders that both production idle time and penalties on tardiness and earliness of orders are minimized. The proposed methodology is tested on a small example to illustrate the effect of the frozen interval. The results indicate that the suggested approach can improve the schedule stability while retaining efficiency.

关键词： Dynamic advanced planning and scheduling Genetic algorithm Frozen interval

Controlling Thermal Conduction by Graded Materials

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Communications in Theoretical Physics 2018年第4期69卷 434-440页

作者： Qin ji ji-ping Huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (MOE) Fudan University Shanghai 200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

Manipulating thermal conductivities are fundamentally important for controlling the conduction of heat at will. Thermal cloaks and concentrators, which have been extensively studied recently, are actually graded materials designed according to coordinate transformation approaches, and their effective thermal conductivity is equal to that of the host medium outside the cloak or concentrator. Here we attempt to investigate a more general problem: what is the effective thermal conductivity of graded materials? In particular, we perform a first-principles approach to the analytic exact results of effective thermal conductivities of materials possessing either power-law or linear gradation profiles. On the other hand, by solving Laplace's equation, we derive a differential equation for calculating the effective thermal conductivity of a material whose thermal conductivity varies along the radius with arbitrary gradation *** two methods agree with each other for both external and internal heat sources, as confirmed by simulation and experiment. This work provides different methods for designing new thermal metamaterials(including thermal cloaks and concentrators), in order to control or manipulate the transfer of heat.

关键词： thermal metamaterials graded materials effective thermal conductivity