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Bipartite Locating Array

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Acta Mathematica Sinica,English Series 2020年第2期36卷 179-188页

作者： Zong Feng QI wen jie ZHONG Yu TANG State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System(CEME叭Luoyang 471003 P.R.China School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China

As a special case of experimental design,locating array is useful for locating interaction faults in component-based *** this paper,bipartite locating array is proposed to locate interaction faults between two specific *** arrays are especially suitable for antagonism *** on the definition of bipartite locating array,the lower bound on run sizes are established to measure the optimality for specific *** a single fault is to be located,optimal bipartite locating arrays are proved to be equivalent to certain specific combinatorial *** a result,approaches to constructing optimal bipartite locating arrays are proposed and some infinite classes of optimal bipartite locating arrays are obtained using the corresponding construction met hod.

关键词： Bipartite locating arrays interaction faults lower bound optimality

Using chloramine as a coagulant aid in enhancing coagulation of Yellow River water in China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1475-1481页

作者： YANG Wei CHEN jie LI Xing LIANG Heng HE wen-jie LI Gui-bai Department of Environmental Engineering. Harbin University ofCommerce Harbin 150076. China School of Municipal and Environmental Engineering ttarbin Institute of Technology Harbin 150090 China Suzhou Litree Ultra-filtration Membrane Technology Co. Ltd. Suzhou 215152 China College of Civil Engineering and Archltecture Beijing University of Technology Beijing 100023 China Tianjin Waterworks Group Company Ltd Tianjin 300040 China

Considering that contaminated raw water mostly contains high Ammonia-N and a majority of water treatment plants use prechlorination process in China, efficiency of chloramines as a coagulant aid in enhancing coagulation was investigated by Jar stirring and pilot-scale tests, using Yellow River water containing high concentration of natural organic matters （NOM） and bromide in winter. The jar tests results showed that, compared with no preoxidation, preformed chloramine apparently decreased the turbidity of settled and filtered water with low dosage （2.0 rag/L）, and the aid-coagulation efficiency was further enhanced with the increase of chlorine （Cl2） to Ammonia-N （N） ratio. Pilot-scale studies indicated that, in comparison to the case without preoxidation, the turbidity removal efficiency of flotation and filtration effluent water was significantly improved, the particle counts of filtered water were decreased 63.4%, the average rate of filter head loss was reduced 18.2%, and filter run time was prolonged 15.7%. Therefore, chloramine preoxidation may substantially enhance the particle separation efficiency.

关键词： Preoxidation Chloramine Pilot plant Turbidity Particle counts Filter run time

Bottom-up construction of mesoporous supramolecular isomers based on a Pd_(3)L_(6) triangular prism as templates for shape specific aggregation of polyiodide

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Nano Research 2022年第3期15卷 2655-2660页

作者： wen-jie Shi Xin Li Peng Li Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China

Bottom-up construction of highly complex architecture from simple components remains one of the long-standing challenges in *** two supramolecular isomers based on large trigonal prismatic Pd_(3)L^(1)_(6)building block are ***,they can be controllably obtained by adjusting the solute concentration during crystal ***,the square shape crystals,α-[Pd_(3)L^(1)_(6)](PF_(6))_(12)in the cubic system with I143 m space group,can be isolated from a high-concentration solution of Pd_(3)L^(1)_(6).Interestingly,a mesoporous cage assembled from eight Pd_(3)L^(1)_(6)units with a diameter of 24Åis observed in the crystal *** the low-concentration solution of Pd_(3)L^(1)_(6),the rectangular shape crystalsβ-[Pd_(3)L^(1)_(6)](PF_(6))_(12)are obtained,which crystallize in the hexagonal system with P 63/m space group,and display two-dimension packing pattern and one-dimension mesoporous channels(diameter ca.22Å)along the c ***,the two supramolecular isomers were used as nanoporous reactors to induce the specific formation of polyiodides with different compositions and shapes as evidenced from single crystal X-ray diffraction *** findings provide a reference in targeting functional crystalline mesoporous supramolecular materials from a single complex building unit.

关键词： supramolecular isomers crystal growth self-assembly polyiodide concentration effect mesoporous supramolecular material

Enhancing MXene-based supercapacitors:Role of synthesis and 3D architectures

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Journal of Energy Chemistry 2024年第4期91卷 1-26页

作者： wen Siong Poh wen jie Yiang Wee-Jun Ong Pau Loke Show Chuan Yi Foo School of Energy and Chemical Engineering Xiamen University MalaysiaSelangor Darul EhsanMalaysia&College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Kelip-kelip!Center of Excellence for Light Enabling Technologies Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Center of Excellence for NaNo Energy&Catalysis Technology(CONNECT) Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Department of Chemical Engineering Khalifa UniversityShakhbout Bin Sultan St-Zone 1Abu DhabiUnited Arab Emirates Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection Wenzhou UniversityWenzhou 325035ZhejiangChina Department of Chemical and Environmental Engineering Faculty of Science and EngineeringUniversity of Nottingham MalaysiaJalan Broga43500 SemenyihSelangor Darul EhsanMalaysia Department of Sustainable Engineering Saveetha School of EngineeringSIMATSChennai 602105India

MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic *** its various desirable properties including intrinsic flexibility,high specific surface area,excellent metallic conductivity and unique abundance of surface functionalities,its full potential for electrochemical performance is hindered by the notorious restacking phenomenon of MXene *** to its two-dimensional(2D)nature and surface functional groups,inevitable Van der Waals interactions drive the agglomeration of nanosheets,ultimately reducing the exposure of electrochemically active sites to the electrolyte,as well as severely lengthening electrolyte ion transport *** a result,energy and power density deteriorate,limiting the application versatility of MXene-based *** 3D architectures using 2D nanosheets presents as a straightforward yet ingenious approach to mitigate the fatal flaws of ***,the sheer number of distinct methodologies reported,thus far,calls for a systematic review that unravels the rationale behind such 3D MXene structural ***,this review aims to serve this purpose while also scrutinizing the structure–property relationship to correlate such structural modifications to their ensuing electrochemical performance ***,the physicochemical properties of MXene play fundamental roles in determining the effective charge storage capabilities of 3D MXene-based *** largely depends on different MXene synthesis techniques and synthesis condition variations,hence,elucidated in this review as ***,the challenges and perspectives for achieving viable commercialization of MXene-based supercapacitor electrodes are highlighted.

关键词： MXene 3D architectures Synthesis design Supercapacitor Energy storage

Combined energy detection and one-order cyclostationary feature detection techniques in cognitive radio systems

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 18-25页

作者： YUE wen-jing ZHENG Bao-yu MENG Qing-min YUE wen-jie Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China Shanxi Institute of Educational Science Taiyuan 030009 China

One of the main requirements of cognitive radio systems is the ability to detect the presence of the primary user with fast speed and precise accuracy. To achieve that, a possible two-stage spectrum sensing scheme is suggested in this paper. More specifically, a fast spectrum sensing algorithm based on the energy detection is introduced focusing on the coarse detection. A complementary fine spectrum sensing algorithm adopts one-order cyclostationary properties of primary user＇s signals in time domain. Since the one-order feature detection is performed in time domain, the real-time operation and low-computational complexity can be achieved. Also, it drastically reduces hardware burdens and power consumption as opposed to two-order feature detection. The sensing performance of the proposed method is studied and the analytical performance results are given. The results indicate that better performance can be achieved in proposed two-stage sensing detection compared to the conventional energy detector.

关键词： cognitive radio (CR) spectrum sensing energy detector cyclostationary feature detector

A class of transient acceleration models consistent with Big Bang cosmology

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Research in Astronomy and Astrophysics 2014年第2期14卷 129-138页

作者： Tian-Long Zu jie-wen Chen Yang Zhang Key Laboratory for Researches in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China

Is it possible that the current cosmic accelerating expansion will turn into a decelerating one？ Can this transition be realized by some viable theoretical model that is consistent with the standard Big Bang cosmology？ We study a class of phenomeno- logical models with a transient acceleration, based on a dynamical dark energy with a very general form of equation of state Pde = αPde -- βpdem. It mimics the cosmolog- ical constant αde → const for a small scale factor a, and behaves as a barotropic gas with pde → α-3（α＋1） with α 〉 0 for large a. The cosmic evolution of four models in the class has been examined in detail, and all yield a smooth transient acceleration. Depending on the specific model, the future universe may be dominated by either dark energy or by matter. In two models, the dynamical dark energy can be explicitly real- ized by a scalar field with an analytical potential V（O）. Moreover, a statistical analysis shows that the models can be as robust as ACDM in confronting the observational data of Type Ia supernovae, cosmic microwave background （CMB） and baryon acoustic os- cillation. As improvements over previous studies, our models overcome the problem of over-abundance of dark energy during early eras, and satisfy the constraints on dark energy from WMAP observations of CMB.

关键词： cosmology: theory -- methods: analytical

Wetting patterns and bacterial distributions in different soils from a surface point source applying effluents with varying Escherichia coli concentrations

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Journal of Integrative Agriculture 2016年第7期15卷 1625-1637页

作者： wen jie LI Jiu-sheng LI Yan-feng State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources andHydropower ResearchBeijing 100048P.R.China

Understanding bacterial transportation in unsaturated soil is helpful for reducing and avoiding pathogenic contamination that may be induced by irrigation with reclaimed waste water and for developing better irrigation management practic-es. Experiments were conducted to study the transport of a typical bacterium,Escherichia coli （E. coli）, in a sandy and a sandy loam soil under different application rates and input concentrations. A 30° wedge-shaped plexiglass container was used to represent one twelfth of the complete cylinder in the experiments. The apparent cylindrical application rate varied from 1.05 to 5.76 L h–1 and the input concentration ofE. coli from magnitude of 102 to 107 colony-forming unit （CFU） mL–1. For a given volume of water applied, an increase in application rate resulted in an increase in the wetted radius and a decrease in the wetted depth. In the sandy loam soil, the water spread out in a circular-arc shaped saturated zone on the surface, and the ultimate saturated entry radius increased with the application rate. An increasing application rate of water suspended bacteria alowed a more rapid transport of bacteria, thus acceleratingE. coli transport rate and resulting in a larger distributed volume ofE. coli for both soil types. For the sandy soil, more than 70% of theE. coli that was de-tected within the entire wetted volume concentrated in the range of 10 cm from the point source, and the concentration of E. colidecreased greatly as the distance from the point source increased. More than 98% of theE. coli was detected in a range of 5 cm around the saturated wetted zone for the sandy loam soil. For both soil types tested, an extremely high concentration ofE. coli was observed in the proximity of the point source, and the peak value increased with an increased input concentration. In principle, using an emitter with relative lower application rate would be effective to restrictE. coli transport. To reduce bacterial concentration in the sewage

关键词： application rate drip irrigation Escherichia coli input concentration

Fabrication of Macroporous Protein-containing Films through the Reverse Emulsions Approach Featuringβ-Cyclodextrin-conjugated PEG-PLGA Copolymers

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Chinese Journal of Polymer Science 2016年第6期34卷 730-738页

作者： ji-jie wen 吕宏光 de-e liu 高辉 School of Chemistry and Chemical Engineering Tianjin Key Laboratory of Organic Solar Cells and Photochemical ConversionTianjin University of TechnologyTianjin 300384China

A series of β-cyclodextrin-conjugated 4-arm poly（ethylene glycol）-poly（lactide-co-glycolide）（4-arm PEG-PLGA） copolymers were synthesized by a ring-opening polymerization of D,L-lactide and glycolide using 4-arm PEG as initiator, and then conjugated with mono（6-ethylenediamine-6-deoxy）- β-cyclodextrin （CDen） or ethylenediamino-bridged bis- β-CD （BCDen）. The chemical structures of copolymers were confirmed by IH-NMR and FTIR spectroscopy. The , β-CD-conjugated PEG-PLGA formed stable reverse micelles due to the formation of fl-CD and bovine serum albumin （BSA） inclusion complexation, which could accommodate BSA in the organic solvent with improved encapsulation efficiency. Moreover, we demonstrated a one-step approach to construct macroporous protein-containing films using these reverse micelles. The films with ordered pore arrays were directly prepared from reverse micelles. Interestingly, the protein was totally located in the whole matrix except for the pores.

关键词： β-Cyclodextrin Copolymer Reverse micelles Ordered porous structures Proteins.

Methanation of carbon dioxide on Ni/ZrO_2-Al_2O_3 catalysts:Effects of ZrO_2 promoter and preparation method of novel ZrO_2-Al_2O_3 carrier

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Journal of Natural Gas Chemistry 2011年第3期20卷 318-324页

作者： Mengdie Cai jie wen Wei Chu Xueqing Cheng Zejun Li Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China Southwest Research ＆ Design Institute of Chemical Industry Chengdu 610000 Sichuan China

The novel nickel-based catalysts with a nickel content of 12 wt% were prepared with the zirconia-alumina composite as the supports. The new carriers, ZrO2 improved alumina, were synthesized by three methods, i.e., impregnation-precipitation, co-precipitation, and impregnation method. The catalytic properties of these catalysts were investigated in the methanation of carbon dioxide, and the samples were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscope （XPS）, temperature-programmed reduction （TPR） and temperature-programmed desorption （TPD） techniques. The new catalysts showed higher catalytic activity and better stability than Ni/γ-Al2O3. Furthermore, as a support for new nickel catalyst, the ZrO2-Al2O3 composite prepared by the impregnation-precipitation method was more efficient than the other supports in the methanation of carbon dioxide. The highly dispersed zirconium oxide on the surface of γ-Al2O3 inhibited the formation of nickel aluminate-like phase, which was responsible for the better dispersion of Ni species and easier reduction of NiO species, leading to the enhanced catalytic performance of corresponding catalyst.

关键词： zirconia-alumina composite nickel catalyst CO2 methanation preparation method