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Experimental study on pressurized activated sludge process for high concentration pesticide wastewater

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Journal of Environmental Sciences 2010年第9期22卷 1342-1347页

作者： Zanfang jin, zhiyan Pan, Shangqin Yu, Chunmian Lin College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China. College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

Pressurized biochemical process derived from traditional activated sludge processes is an innovative technology for wastewater treatment. The main advantage of the pressurized process is that the oxygen transfer barrier can be overcome by increasing the dissolved oxygen level. In this study, high concentration pesticide wastewater was treated by pressurized activated sludge process. It was found that the removal of chemical oxygen demand （COD） increased steadily with the increase of operating pressure, aeration time, and sludge concentration. When the operation pressure was 0.30 MPa and the aeration time was 6 hr, 85.0%-92.5% COD, corresponding to an effluent COD of 230-370 mg/L, was removed from an influent COD of 2500-5000 mg/L. The obtained outlet COD concentration was lower than 350-450 mg/L for the identical process operated under the atmospheric pressure. In addition, pressurized biochemical process could produce a higher COD volumetric loading rate at 5.8-7.6 kg COD/（m^***）, compared with 2.0-2.8 kg COD/（***） using the same equipment at the atmospheric pressure. The COD concentration followed a modified Monod model with Vmax 2.31 day-1 and Ks 487 mg/L.

关键词： pressurized biochemical process pesticide wastewater activated sludge kinetics

计算机辅助药物设计技术在药物化学教学中的应用与探索

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卫生职业教育 2024年第19期42卷 44-47页

作者：葛军李英鹏邓雁如牟佳佳金志艳天津中医药大学中药学院天津301617 天津体育学院天津301617

以天津中医药大学为例开展可视化教学,借助新兴的计算机辅助药物设计(CADD)软件Discovery Studio,将其部分功能运用到药物化学课程教学中,使原本抽象、晦涩难懂的内容变成立体的、生动形象的图像,极大地改善了教学效果,为药物化学教学... 详细信息

以天津中医药大学为例开展可视化教学,借助新兴的计算机辅助药物设计(CADD)软件Discovery Studio,将其部分功能运用到药物化学课程教学中,使原本抽象、晦涩难懂的内容变成立体的、生动形象的图像,极大地改善了教学效果,为药物化学教学研究提供了有益借鉴。

关键词：计算机辅助药物设计药物化学可视化教学

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Control of chiral-optical activities by magnetic field based on the transformation of achiral binary crystals into chiral ternary crystals

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Science China Chemistry 2024年第7期67卷 2300-2305页

作者： zhiyan Chen Yan Lv Wei Qin College of Physics Qingdao UniversityQingdao 266071China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shandong Linuo Photovoltaic Hi-Tech Co. Ltd.Jinan 250100China

Multicomponent self-assembled chiral systems have attracted great attention due to their promising application in the area of spin-photonics and *** this work,through introducing an achiral third component into an achiral binary crystal,a chiral organic ternary crystal is fabricated,where both pronounced chiral-optical coupling and magnetic field dependence of chiral-optical activities are *** transformation of achiral structure into chiral structure generates a significant effect on the polarized state of light and the electron spin resonance ***,the coupling between circularly polarized photon and spin is observed in chiral ternary crystal with pronounced chiral orbit,where obvious magnetic field-transmissivity loop is ***,temperature could increase the magnitude of lattice parameters to lead to a larger helix radius to increase the chiral orbit ***,this work indicates that the further exploration of photon-chiral orbit-spin interactions in organic chiral ternary crystals is promising.

关键词： organic chiral ternary crystals chiral orbit chiral-optical activities magnetic field

Effects of cement-enhanced soil on the ultimate lateral resistance of composite pile in clayey soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 183-191页

作者： Zhijun Yang Kexin Chen Xudong Fu zhiyan Zou School of Civil Engineering Wuhan UniversityWuhan430000China Changjiang Design Group Co. Ltd.Wuhan430000China Institute of Geotechnical Engineering College of Civil Engineering and ArchitectureMOE Key Laboratory of Soft Soils and Geoenvironmental EngineeringZhejiang UniversityHangzhou310000China

The composite pile consisting of core-pile and surrounding cement-enhanced soil is a promising pile foundation in recent ***,how and to what extent the cement-enhanced soil influences the ultimate lateral resistance has not been fully *** this paper,the ultimate lateral resistance of the composite pile was studied by finite element limit analysis(FELA)and theoretical upper-bound *** results of FELA and theoretical analysis revealed three failure modes of laterally loaded composite *** effects of the enhanced soil thickness,strength,and pile-enhanced soil interface characteristics on the ultimate lateral resistance were *** results show that increasing the enhanced soil thickness leads to a significant improvement on ultimate lateral resistance factor(N P),and there is a critical thickness beyond which the thickness no longer affects the N *** the enhanced soil strength induced 6.2%-232.6%increase of N ***,no noticeable impact was detected when the enhanced soil strength was eight times higher than that of the natural *** maximum increment of N P is only 30.5%caused by the increase of interface adhesion factor(a).An empirical model was developed to calculate the N P of the composite pile,and the results show excellent agreement with the analytical results.

关键词： Composite pile Ultimate soil resistance Finite element limit analysis(FELA) Plasticity theory Failure mode

Research on mass loss and nose shape evolution of kinetic energy projectiles penetrating concrete at high velocity

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Acta Mechanica Sinica 2024年第7期40卷 92-108页

作者： zhiyan Yao Fenglei Huang jinzhu Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The high-speed penetration of concrete targets by kinetic energy projectiles results in apparent mass loss,which blunts the nose of the projectile and decrease its penetration *** friction work between the projectile and the concrete target,the plastic deformation of the projectile,and the cutting of aggregates to the projectile significantly affect the mass loss of the *** address these effects,a discrete iterative model is developed for the mass loss and nose shape evolution of the projectile by coupling three mechanisms based on the effect of temperature on *** the model,both friction work and plastic work increase the temperature of the projectile's surface layer,thereby weakening the strength of this part and rendering it easier for mass loss to occur due to aggregate *** model discretizes the projectile and penetration process with respect to the space and time dimensions,*** mass loss and nose shape evolution of the projectile are obtained by iteratively calculating a point-by-point *** predicted depth of penetration(DOP),mass loss,and residual projectile profile are compared with experimental data to validate the *** comparison shows satisfactory agreement between the calculated results and experimental ***,the deceleration,velocity,DOP,and mass loss during penetration are analyzed with respect to ***,based on the model,the effects of projectile strength,caliber-radius-head(CRH),and concrete target strength on penetration are discussed.

关键词： Kinetic energy projectile High-velocity penetration Coupled model Mass loss Nose shape evolution

A REDUCED ORDER SCHWARZ METHOD FOR NONLINEAR MULTISCALE ELLIPTIC EQUATIONS BASED ON TWO-LAYER NEURAL NETWORKS

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Journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen zhiyan Ding Qin Li Stephen J.Wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

A new-generation sand and dust storm forecasting system GRAPES_CUACE/Dust:Model development,verification and numerical simulation

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Chinese Science Bulletin 2010年第24期55卷 635-649页

作者： WANG Hong GONG ShanLing ZHANG HongLiang CHEN Yong SHEN XueShun CHEN DeHui XUE JiShan SHEN YuanFang WU XiangJun jin zhiyan Centre for Atmosphere Watch and Services Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Severe Weathet. Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Based on the new-generation Global/Regional Assimilation and PrEdiction System(GRAPES) developed by the Numerical Prediction Research Center,China Meteorological Administration and the Chinese Unified Atmospheric Chemistry Environment for Dust Atmospheric Chemistry Module(CUACE/Dust) developed by the Centre for Atmosphere Watch and Services(CAWAS) of the Chinese Academy of Meteorological Sciences(CAMS) ,the China sand and dust storm forecasting system GRAPES /CUACE-Dust model has been *** latest data of land desertification,optical properties of China sand and dust aerosols,daily soil moisture and snow cover over China main land was introduced in this *** system showed good performance in mass *** comparisons of real-time prediction outputs with surface observations and aerosol indices derived from TOMS ozone spectrophotometers(TOMS AI) indicate that the model can predict the outbreak,development,transport and depletion processes of sand and dust storms accurately over China and the East Asian *** system makes real-time quantitative prediction of a series of elements including sand and dust injection from the surface,dry and wet deposition amount,dust concentration and optical *** selected 7 major dust storms occurring in April 2006 and analyzed the spatiotemporal distribution patterns of dust emission,dry and wet deposition and atmospheric load in this *** results showed that about 225 million tons of dust were emitted into the atmosphere from the deserts over east Asia in that *** 3 major sand and dust sources were just as the following:The deserts in northern Inner Mongolia and the boundary area around China-Mongolia were the first dust sources with a contribution of 153 million tons accounting for 68%of the total *** Taklimakan Desert ranked second and contributed approximately 40 million tons accounting for 17%of the dust *** Onqin Daga Sandland emitted about 15 million tons or 7%of the t

关键词： mesoscale 沙和灰尘暴风雨预报系统喷雾器干燥免职湿免职

GRAPES全球模式MPI与OpenMP混合并行方案

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应用气象学报 2014年第5期25卷 581-591页

作者：蒋沁谷金之雁中国气象科学研究院北京100081 中国气象局数值预报中心北京100081

随着多核计算技术的发展,基于多核处理器的集群系统逐渐成为主流架构。为适应这种既有分布式又有共享内存的硬件体系架构,使用MPI与OpenMP混合编程模型,可以实现节点间和节点内两级并行,利用消息传递与共享并行处理两种编程方式,MPI用... 详细信息

随着多核计算技术的发展,基于多核处理器的集群系统逐渐成为主流架构。为适应这种既有分布式又有共享内存的硬件体系架构,使用MPI与OpenMP混合编程模型,可以实现节点间和节点内两级并行,利用消息传递与共享并行处理两种编程方式,MPI用于节点间通信,OpenMP用于节点内并行计算。该文采用MPI与OpenMP混合并行模型,使用区域分解并行和循环并行两种方法,对GRAPES全球模式进行MPI与OpenMP混合并行方案设计和优化。试验结果表明:MPI与OpenMP混合并行方法可以在MPI并行的基础上提高模式的并行度,在计算核数相同的情况下,4个线程内的MPI与OpenMP混合并行方案比单一MPI方案效果好,但在线程数量大于4时,并行效果显著下降。

关键词：混合并行数值天气预报模式区域分解循环并行

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大规模并行程序通信性能分析

华中科技大学学报（自然科学版） 2011年第S1期39卷 71-75页

作者：翟琰翟季冬薛巍金之雁清华大学计算机科学与技术系北京100084 中国气象科学研究院北京100081

选取基准测试程序集SPECMPI的4个程序,以及我国研制的天气预报并行应用GRAPES,在消息传递接口层面(MPI)以及不同的平台上对这5个程序的通信性能进行了插装采集和分析,并使用进程映射的方法进行通信优化.实验结果表明上述方法可完成对较... 详细信息

选取基准测试程序集SPECMPI的4个程序,以及我国研制的天气预报并行应用GRAPES,在消息传递接口层面(MPI)以及不同的平台上对这5个程序的通信性能进行了插装采集和分析,并使用进程映射的方法进行通信优化.实验结果表明上述方法可完成对较大规模的并行程序的性能数据采集,这对于定位和优化并行程序的性能起到重要作用;在通信性能较差的以太网平台上,进程映射的效果较为明显,而在通信性能较高的Infiniband网络上,进程映射的效果不明显,因此,在选择优化方案时,还需要注意目标平台的性能指标.

关键词：并行计算通信性能分析基准测试程序气象预报进程映射