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Frontiers of Environmental Science & Engineering 2008年第1期2卷 57-62页

作者： haifeng jia Wei WEI Kunlun XIN Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China College of Environmental Science and Engineering Tongji UniversityShanghai 200092China

Water shortage is one of the major water related problems for many cities in the *** planning for utilization of reclaimed water has been or would be drafted in these *** using the reclaimed water soundly,Beijing planned to build a large scale reclaimed water pipe networks with *** order to support the plan,the integrated hydraulic model of planning pipe network was developed based on EPANET supported by geographic information system(GIS).The complicated pipe network was divided into four weak conjunction subzones according to the distribution of reclaimed water plants and the *** could provide a better solution for the problem of overhigh pressure in several regions of the *** the scenarios analy-sis in different subzones,some of the initial diameter of pipes in the network was *** last the pipe network planning scheme of reclaimed water was *** proposed planning scheme could reach the balances between reclaimed water requirements and reclaimed water supplies,and provided a scientific basis for the reclaimed water utilization in *** the scheme had been adopted by Beijing municipal government.

关键词： hydraulic model multi-sources reclaimed water pipe network EPANET GIS Beijing

China＇s Sponge City construction： A discussion on technical approaches

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 39-49页

作者： haifeng jia Zheng Wang Xiaoyue Zhen Mike Clar Shaw L. Yu School of Environment Tsinghua University Beijing 100084 China Beijing Orient Tetra Tech Ecological Technology Ltd. Beijing 100051 China Tetra Tech Fairfax VA 22030 USA Department of Civil & Environmental Engineering University of Virginia Charlottesville VA 22904 USA

Since 2014, China has been implementing the Sponge City Construction initiative, which represents an enormous and unprecedented effort by any government in the world for achieving urban sustainability. According to preliminary estimates, the total investment on the Sponge City Plan is roughly 100 to 150 million Yuan （RMB）（$15 to $22.5 million） average per square kilometer or 10 Trillion Yuan （RMB）（$1.5 Trillion） for the 657 cities nationwide. The Sponge City Plan （SCP） calls for the use of natural processes such as soil and vegetation as part of the urban runoff control strategy, which is similar to that of low impact development （LID） and green infrastructure （G1） practices being promoted in many parts of the world. The SCP includes as its goals not only effective urban flood control, but also rainwater harvest, water quality improvement and ecological restoration. So far, the SCP implementation has encountered-some barriers and challenges due to many factors. The present paper presents a review of those barriers and challenges, oftizrs discussions and recommendations on several technical aspects such as control goals and objectives; planning/design and construction of LID/GI practices; performance evaluation. Several key recommendations are proposed on Sponge City implementation strategy, Site-specific regulatory fi＇amework and technical gmdance, Product innovation and certification, LID/GI Project financing, LID/G1 profcssional training and certification, public outreach and education. It is expected that the successful implemen!atiun of the. SCP not only will bring about a sustainable, eco-friendly urbanization process in China, but also contribute enormously to the LID/Gl research and development with the vast amount of relevant data and experiences generated from the Sponge City construction projects.

关键词： Low impact development Green infrastructure (GI) Sponge City Barriers Construction strategies

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石煤提钒尾渣成分分析及银的综合利用研究

矿产与地质 2024年第4期38卷 708-712,732页

作者：王峰孙猛刘恒杰倪海燕罗琦林陈晨兰绿灯贾海峰谭清月李国栋湖北冶金地质研究所〔中南冶金地质研究所〕湖北宜昌443003

石煤提钒的产品纯度均高于钒钛磁铁矿的提钒产品纯度,更适合作为钒原料运用于为电池、电子、超导等高纯度要求的产品,因此石煤钒矿产的利用日显其重要性。文章开展了石煤提钒后的尾渣成分分析及综合利用研究。湖北某地石煤提钒尾渣的化... 详细信息

石煤提钒的产品纯度均高于钒钛磁铁矿的提钒产品纯度,更适合作为钒原料运用于为电池、电子、超导等高纯度要求的产品,因此石煤钒矿产的利用日显其重要性。文章开展了石煤提钒后的尾渣成分分析及综合利用研究。湖北某地石煤提钒尾渣的化学成分分析结果表明,尾渣及浸取液残留有较高的银和钒。尾渣中银和钒的赋存状态分析结果显示,钒主要残留在云母类矿物中,现阶段再利用的综合成本较高,而银主要存在于硫化物及其它硅酸盐类矿物中,通过浮选—重选的选矿模式可以回收,据此确定该矿的钒尾渣的综合利用方向为浮选—重选回收银。为此设计一套不同粒级、不同比重的钒尾渣选矿实验流程,实验结果证明该选矿流程能够有效实现该钒尾渣中有价元素银的回收利用。本研究提出一套适用于钒尾渣中银的物相分析方法及选矿试验流程,值得相关企业推广应用。

关键词：钒尾渣赋存状态银综合利用

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江苏省宿迁地区秋冬茬白芹农艺性状比较

中国农学通报 2024年第19期40卷 40-46页

作者：吴小雪陈晨王俐翔曾晓萍刘佩卓王雅慧刘燕花贾海锋束胜熊爱生南京农业大学园艺学院/作物遗传与种质创新利用全国重点实验室/农业农村部华东地区园艺作物生物学与种质创制重点实验室南京210095 宿迁市设施园艺研究院(南京农业大学宿迁研究院) 江苏宿迁223800 江苏省农业技术推广总站南京210036

为解决江苏宿迁地区芹菜生产以绿芹为主、品种相对单一的问题,以2022年秋季种植于江苏省宿迁市洋河新区的29种白芹为试验材料,开展主要农艺性状的比较,对其8个农艺性状进行差异性分析、相关性分析、主成分分析以及聚类分析。结果表明,白... 详细信息

为解决江苏宿迁地区芹菜生产以绿芹为主、品种相对单一的问题,以2022年秋季种植于江苏省宿迁市洋河新区的29种白芹为试验材料,开展主要农艺性状的比较,对其8个农艺性状进行差异性分析、相关性分析、主成分分析以及聚类分析。结果表明,白芹8个农艺性状的变异系数为9.390%~71.610%,其中单株质量、株高、叶柄长、叶柄厚和叶柄数的变异系数均大于20%,表明不同白芹品种间这5个农艺性状差异较大。相关性分析显示,除叶柄数与叶柄宽、叶柄厚呈负相关外,其余各性状间均呈正相关关系,其中单株质量与其余性状均呈极显著正相关性。主成分分析显示,前2个主成分的累计贡献率为77.005%。通过聚类分析,可在遗传距离为7.5处将29种白芹种质资源分为3个类群。

关键词：芹菜农艺性状差异性分析相关性分析主成分分析聚类分析

Dual-Schottky-junctions coupling device based on ultra-longβ-Ga_(2)O_(3)single-crystal nanobelt and its photoelectric properties

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Journal of Semiconductors 2024年第5期45卷 90-98页

作者： haifeng Chen Xiaocong Han Chenlu Wu Zhanhang Liu Shaoqing Wang Xiangtai Liu Qin Lu Yifan jia Zhan Wang Yunhe Guan Lijun Li Yue Hao Key Laboratory of Advanced Semiconductor Devices and Materials School of Electronic EngineeringXi’an University of Posts andT elecommunicationsXi’an 710121China State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi'an 710071China

High qualityβ-Ga_(2)O_(3)single crystal nanobelts with length of 2−3 mm and width from tens of microns to 132μm were synthesized by carbothermal reduction *** on the grown nanobelt with the length of 600μm,the dual-Schottky-junctions coupling device(DSCD)was *** to the electrically floating Ga_(2)O_(3)nanobelt region coupling with the double Schottky-junctions,the current I_(S2)increases firstly and rapidly reaches into saturation as increase the voltage V_(S2).The saturation current is about 10 pA,which is two orders of magnitude lower than that of a single *** the case of solar-blind ultraviolet(UV)light irradiation,the photogenerated electrons further aggravate the coupling physical mechanism in device.I_(S2)increases as the intensity of UV light *** the UV light of 1820μW/cm^(2),I_(S2)quickly enters the saturation *** V_(S2)=10 V,photo-to-dark current ratio(PDCR)of the device reaches more than 104,the external quantum efficiency(EQE)is 1.6×10^(3)%,and the detectivity(D*)is 7.5×10^(12)*** addition,the device has a very short rise and decay times of 25−54 ms under different positive and negative *** shows unique electrical and optical control characteristics,which will open a new way for the application of nanobelt-based devices.

关键词： β-Ga_(2)O_(3)nanobelt carbothermal reduction UV light dual-Schottky coupling device

High-silica faujasite zeolite-tailored metal encapsulation for the low-temperature production of pentanoic biofuels

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Journal of Energy Chemistry 2024年第1期88卷 552-560,I0012页

作者： Wenhao Cui Yuanshuai Liu Pengfei Guo Zhijie Wu Liqun Kang Huawei Geng Shengqi Chu Linying Wang Dong Fan Zhenghao jia haifeng Qi Wenhao Luo Peng Tian Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101ShandongChina College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021Inner MongoliaChina State Key Laboratory of Heavy Oil Processing and Key Laboratory of Catalysis of CNPC China University of PetroleumBeijing 102249China Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy ConversionMülheim an der Ruhr 45470Germany Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Division of Energy Research Resources Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Leibniz-Institut für Katalyse Albert-Einstein-Straβe 29aRostock 18059Germany

Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable ***,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant ***,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal *** with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.

关键词： High-silica zeolite Y Metal encapsulation Bifunctional catalysis Hydrodeoxygenation Biofuels

Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia WEN Yan Yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable *** also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal *** this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal ***,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity *** by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

TCAS-PINN:Physics-informed neural networks with a novel temporal causality-based adaptive sampling method

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Chinese Physics B 2024年第5期33卷 344-364页

作者：郭嘉王海峰古仕林侯臣平 College of Science National University of Defense TechnologyChangsha 410073China

Physics-informed neural networks(PINNs)have become an attractive machine learning framework for obtaining solutions to partial differential equations(PDEs).PINNs embed initial,boundary,and PDE constraints into the loss *** performance of PINNs is generally affected by both training and ***,training methods focus on how to overcome the training difficulties caused by the special PDE residual loss of PINNs,and sampling methods are concerned with the location and distribution of the sampling points upon which evaluations of PDE residual loss are ***,a common problem among these original PINNs is that they omit special temporal information utilization during the training or sampling stages when dealing with an important PDE category,namely,time-dependent PDEs,where temporal information plays a key role in the algorithms *** is one method,called Causal PINN,that considers temporal causality at the training level but not special temporal utilization at the sampling *** temporal knowledge into sampling remains to be *** fill this gap,we propose a novel temporal causality-based adaptive sampling method that dynamically determines the sampling ratio according to both PDE residual and temporal *** designing a sampling ratio determined by both residual loss and temporal causality to control the number and location of sampled points in each temporal sub-domain,we provide a practical solution by incorporating temporal information into *** experiments of several nonlinear time-dependent PDEs,including the Cahn–Hilliard,Korteweg–de Vries,Allen–Cahn and wave equations,show that our proposed sampling method can improve the *** demonstrate that using such a relatively simple sampling method can improve prediction performance by up to two orders of magnitude compared with the results from other methods,especially when points are limited.

关键词： partial differential equation physics-informed neural networks residual-based adaptive sampling temporal causality

Geometric Constraints for Global Regularity of 3D Shear Thickening Fluids

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 205-210页

作者： jia-qi Yang Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China

We consider the relation between the direction of the vorticity and the global regularity of 3D shear thickening *** is showed that a weak solution to the non-Newtonian incompressible fluid in the whole space is stron... 详细信息

关键词： direction of the vorticity non-Newtonian fluid global regularity

Two-dimensional ballistic transistors for advanced-node integrated circuits

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National Science Review 2024年第3期11卷 9-10页

作者： jia Li Xidong Duan Hunan Provincial Key Laboratory of Two-Dimensional Materials State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University

As the feature size of metal-oxide-semiconductor-field-effect-transistors(MOSFETs) in integrated circuits(ICs)is reduced to sub-10-nm, the traditional channel materials are plagued by enhanced scattering and short-cha... 详细信息

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