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Studies on GIS Based Tracing and Traceability of Safe Crop Product in China

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Agricultural Sciences in China 2007年第6期6卷 724-731页

作者： QU Xiao-hui ZHUANG Da-fang qiu dong-sheng Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P.R.China

The safety of safe crop products （SCP） is critical to maintain people＇s health and living standard. With the global efforts on the improvement of the traceability of food products, it is inevitable to establish corresponding traceability systems to monitor the safety of crop products in China. In this article, the supply chain pattern of SCP in China has been analyzed and its spatial characters have been described in detail. The study deals with on how to relate traceability technology with GIS, and on how to trace and retrace the safety of SCP using the function of excellent spatial representation, spatial locating, and spatial analysis provided in GIS, which has been discussed from several aspects, such as coding technique of traceability information, transferring technique of traceability information, spatialization of traceability information, and application integration of traceability system. A pilot study was carried out to present the basic functions of the system, which provided an efficient and credible way to trace and retrace the safety of SCP in a real supply chain. An innovative idea has been brought forward for how to establish an efficient, credible, applied traceability system of SCP.

关键词： safe crop products (SCP) tracing and traceability GIS traceability code information transformation

Strategies to advance thermoelectric performance of PbSe and PbS materials

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Rare Metals 2024年第9期43卷 4099-4114页

作者： Zheng-Hao Hou Xin Qian qiu-Juan Cui Shu-fang Wang Li-dong Zhao Shijiazhuang Key Laboratory of Low Carbon Energy Materials College of Chemical EngineeringShijiazhuang UniversityShijiazhuang 050035China Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Thermoelectric materials possess the unique capability to convert thermal energy into electric energy and vice versa,making them promising for waste heat recovery and efficient cooling ***,extensively investigated thermoelectric materials such as Bi2Te3,PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature ***,the broad application of these thermoelectric materials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth's *** the past few years,researchers have shown increasing interest in PbSe-and PbS-based materials,primarily attributed to their abundant elemental supply and relatively low *** assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric *** strategies include optimizing carrier concentration(aliovalent doping,dynamic doping and defect state),enhancing density-of-state effective mass(band convergence,band flattening and energy filtering effect),optimizing carrier mobility(band sharpening and band alignment)and reducing lattice thermal conductivity(all-scale hierarchical defect structures designing).This systematic summary and analysis provide novel insights and perspectives for the development of thermoelectric materials.

关键词： PbSe and PbS thermoelectric materials Carrier concentration Density-of-state effective mass Carrier mobility Lattice thermal conductivity

Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin Luo Hang Li Shan Guo Zhuang Tong Xiaotao Zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

Perfect Matching in k-partite k-graphs and 3-uniform HM-bipartite Hypergraphs

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 636-641页

作者： Chun-qiu fang Mei LU Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

Let H=(V,E)be an n-balanced k-partite k-graph with partition classes V1,...,*** for every legal(k-1)-tuple f contained in V\V1 and for every legal(k-1)-tuple g contained in V\Vk such that f∪g■E(H),we have d(f)+d(g)≥n+*** this paper,we prove that under this condition H must have a perfect *** result of this paper is about the perfect matching in 3-uniform hm-bipartite *** G be a 3-uniform hm-bipartite hypergraph with one of whose sides V1 has the size n,the another side V2 has size 2 *** for all the legal 2-tuple f with|f∩V1|=1 and for all the legal 2-tuple g with|g∩V1|=0,we have d(f)≥n-2 and d(g)>n/2,then G has a perfect matching.

关键词： Perfect matching k-partite k-graph hm-bipartite hypergraph

Photodissociation Exploration for Near-Visible UV Absorption of Molecular Bromine

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Chinese Journal of Chemical Physics 2008年第1期21卷 12-20页

作者： dong-fang Zhang Bing Zhang State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Insti-tute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The photodissociation of Br2 was investigated within the near-visible UV absorption band. Based on the potential curves for the ground and low-lying excited states, the optical cross-sections for the discrete transitions of C1^Пu,B^3Пou^＋, A^3П1u←X^1∑g＋ and their total energy absorption spectrum are derived, and the quantum yield of （Br＋Br6＊） channel are determined correspondingly. The one-dimensional Landau-Zener model is used to evaluate the behavior of curve crossing during photodissociation. The results indicate that the influence of nonadiabatic mechanism, which may be caused by the electronic-vibrational interplay between the 13 and C states, is negligibly small for the （Br＋Br^＊） channel. From the Landau-Zener modeling of the observed product recoil parameter β（Br＋Br）, the best-fit value of the coupling matrix elenment or coupling strength between the diabatic B and C state potentials is obtained.

关键词： Photodissociation Time-dependent wave packet Nonadiabatic mechanism Landau-Zener model

Molecular reconstruction model based on structure oriented lumping and group contribution methods

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1677-1683页

作者： Jincai Chen Zhou fang Tong qiu Department of Chemical Engineering Tsinghua University

Molecular management is a promising technology to face challenges in the refining industry, such as more stringent requirements for product oil and heavier crude oil, and to maximize the value of every molecule in petroleum fractions. To achieve molecular management in refining processes, a novel model that is based on structure oriented lumping(SOL) and group contribution(GC) methods was proposed in this study. SOL method was applied to describe a petroleum fraction with structural increments, and GC method aimed to estimate molecular properties. The latter was achieved by associating rules between SOL structural increments and GC structures. A three-step reconstruction algorithm was developed to build a representative set of molecules from partial analytical data. First, structural distribution parameters were optimized with several properties. Then, a molecular library was created by using the optimized parameters. In the final step, maximum information entropy(MIE) method was applied to obtain a molecular fraction. Two industrial samples were used to validate the method, and the simulation results of the feedstock properties agreed well with the experimental data.

关键词： Molecular reconstruction Structure oriented lumping Group contribution Monte Carlo Maximum information entropy

Coupled simulation of recirculation zonal firebox model and detailed kinetic reactor model in an industrial ethylene cracking furnace

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Chinese Journal of Chemical Engineering 2017年第8期25卷 1091-1100页

作者： Zhou fang Tong qiu Weiguo Zhou Department of Chemical Engineering Tsinghua University

A coupled system simulating both firebox and reactor is established to study the naphtha pyrolysis in an industrial tubular *** firebox model is based on zone method including combustion,radiation,and convection to simulate heat transfer in the furnace.A two-dimensional recirculation model is proposed to estimate the flow field in *** reactor model integrates the feedstock reconstruction model,an auto-generator of detail kinetic schemes,and the reactor simulation model to simulate the reaction process in the tubular *** coupled simulation result is compared with industrial process and shows agreement within short computation time.

关键词： Ethylene cracking Coupled simulation Tubular furnace Recirculation zone modeling Detailed reaction kinetic

Application of convolutional neural networks to large-scale naphtha pyrolysis kinetic modeling

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2562-2572页

作者： Feng Hua Zhou fang Tong qiu Department of Chemical Engineering Tsinghua University Beijing 100084China Beijing Key Laboratory of Industrial Big Data System and Application Beijing 100084China

System design and optimization problems require large-scale chemical kinetic models. Pure kinetic models of naphtha pyrolysis need to solve a complete set of stiff ODEs and is therefore too computational expensive. On the other hand, artificial neural networks that completely neglect the topology of the reaction networks often have poor generalization. In this paper, a framework is proposed for learning local representations from largescale chemical reaction networks. At first, the features of naphtha pyrolysis reactions are extracted by applying complex network characterization methods. The selected features are then used as inputs in convolutional architectures. Different CNN models are established and compared to optimize the neural network *** the pre-training and fine-tuning step, the ultimate CNN model reduces the computational cost of the previous kinetic model by over 300 times and predicts the yields of main products with the average error of less than 3%. The obtained results demonstrate the high efficiency of the proposed framework.

关键词： Convolutional neural network Network motif Naphtha pyrolysis Kinetic modeling

Effect of vacuum annealing on the characteristics of composite pellets containing DBSA-doped polyaniline and Fe nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 236-241页

作者： Qing Wu Hong qiu Chun-ying fang Kun fang School of Applied Science University of Science and Technology Beijing Beijing 100083 China Material Research Center Beijing Institute of Science and Technology Beijing 100081 China

The DBSA-PANI-Fe composite powder with 50wt% of Fe nanoparticles was prepared by mechanically mixing the DBSA-doped polyaniline powder and Fe nanoparticles. The composite powder was compacted to pellets and the pellets were annealed in vacuum at 443,493,543, and 593 K for 60 and 120 min. The conductivity of the pellet increases markedly with increasing the annealing temperature up to 493 K, and then decreases with further increasing the annealing temperature. When the pellet was annealed at 493 K for 60 min, the increment of conductivity reaches a maximum value, and the conductivity is 2.6 times as large as that of the pellet unannealed. The conductivities of the pellets annealed under the conditions of 543 K/120 min, 593 K/60 min, and 593 K/120 min are lower than the conductivity of the pellet unannealed. For all the pellets, the variation in conductivity with temperature reveals that the charge transport mechanism can be considered to be 1-D variable-range-hopping （1-D VRH）. The composite pellet shows a magnetic hysteresis loop independent of the annealing condition. The saturation magnetization is about 5.4×10^4 emu/kg. The saturation field and the coercivity are estimated to be 4.38×10^5 and 3.06×10^4 A/m, respectively. The crystalline structure ofFe nanoparticles in the composites does not change with the annealing condition. The annealing condition cannot destroy the polymer backbones.

关键词： doped polyaniline dodecylbenzene sulfonic acid (DBSA) Fe nanoparticles vacuum annealing structure conductivity magnetization