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1-GENERATOR QUASI-CYCLIC CODES

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Journal of Systems Science & Complexity 2007年第4期20卷 554-561页

作者： junying PEI Xuejun zhang Department of Mathematics Soochow University Suzhou 215006. China

This paper discusses the enumeration of 1-generator quasi-cyclic codes and describes an algorithm which will obtain one, and only one, generator for each 1-generator quasi-cyclic code.

关键词： Direct sum decomposition idempotent quasi-cyclic code.

Sequential Feature Screening for Generalized Linear Models with Sparse Ultra-High Dimensional Data

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Journal of Systems Science & Complexity 2020年第2期33卷 510-526页

作者： zhang junying WANG Hang zhang Riquan zhang Jiajia Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China Department of Statistics East China Normal UniversityShanghai 200241China Department of Epidemiology and Biostatistics University of South CarolinaColumbia 20295USA

This paper considers the iterative sequential lasso(ISLasso)variable selection for generalized linear model with ultrahigh dimensional feature *** ISLasso selects features by estimated parameter sequentially iteratively for the second order approximation of likelihood function where the features selected depend on regulatory *** procedure stops when extended BIC(EBIC)reaches a *** study demonstrates that the new method is a desirable approach over other methods.

关键词： Extended BIC generalized linear model sequential lasso sequential iteration variable screening variable selection

A new neural network algorithm for planarization problems

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Science in China(Series F) 2008年第12期51卷 1947-1957页

作者： zhang junying QIN Qiang School of Computer Science and Engineering Xidian University Xi'an 710071 China

To deal with the planarization problem widely used in many applications including routing very-large-scale integration （VLSI） circuits, this paper points out that only when its vertices are arranged in some specific order in a line can a planar graph be embedded on a line without any cross connections or cross edges. Energy function is proposed to meet the need of embedding a graph on a single line and route it correctly. A Hopfield network is designed according to the proposed energy function for such embedding and routing. The advantage of the proposed method is that it not only can detect if a graph is a planar one or not, but also can embed a planar graph or the maximal planar subgraph of a non-planar graph on a single line. In addition, simulated annealing is employed for helping the network to escape from local minima during the running of the Hopfield network. Experiments of the proposed method and its comparison with some existent conventional methods were performed and the results indicate that the proposed method is of great feasibility and effectiveness especially for the planarization problem of large graphs.

关键词： graph planarization problem planar embedding algorithm Hopfield network energy function simulatedannealing

Preparation and properties of tungsten-doped indium oxide thin films

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Rare Metals 2012年第2期31卷 158-163页

作者： Li, Yuan Wang, Wenwen zhang, junying Wang, Rongming Department of Physics Beijing University of Aeronautics and Astronautics Beijing 100191 China

Tungsten-doped indium oxide (IWO) thin films were deposited on glass substrate by DC reactive magnetron sputtering. The effects of sputtering power and growth temperature on the structure, surface morphology, optical and electrical properties of IWO thin films were investigated. The thickness and surface morphology of the films are both closely dependent on the sputtering power and the substrate temperature. The transparency of the films decreases with the increase of the sputtering power but is not seriously influenced by substrate temperature. All the IWO thin film samples have high transmittance in near-infrared spectral range. With either the sputtering power or the growth temperature increases, the resistivity of the film decreases at the beginning and increases after the optimum parameters. The as-deposited IWO films with minimum resistivity of 6.4 10 4 cm were obtained at a growth temperature of225 C and sputteringpower of 40 W, with carrier mobility of 33.0 cm 2 V 1 s 1 and carrier concentration of 2.8 10 20 cm 3 and the average transmittance of about 81% in near-infrared region and about 87% in visible region.

关键词： In 2 O 3 : W thin film DC magnetron sputtering substrate temperature sputtering current optical and electrical properties

Nanoarchitectonics of MnO_(2)nanotubes as sea urchin-like aggregates for dielectric response and microwave absorption with a wide concentration domain

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Nano Research 2023年第2期16卷 2604-2610页

作者： Zhi-Ling Hou Kunrong Du Yiqin zhang Song Bi junying zhang College of Mathematics and Physics&Beijing Key Laboratory of Environmentally Harmful Chemical Analysis Beijing University of Chemical TechnologyBeijing 100029China 501 Department Xi’an Research Institute of High-TechXi’an 710025China

Designing highly reliable and practical microwave absorbers is one of the most important research directions in the microwave absorbing *** absorbents suffer from concentration-sensitivity and environmental-sensitivity dilemmas in practical ***,sea urchin-like aggregates of MnO_(2)nanotubes were synthesized by a simple hydrothermal method,which exhibit an outstanding impedance matching *** composites based on sea urchin-like aggregates of MnO_(2)nanotubes show excellent microwave absorption performance in a wide concentration domain from 20 wt.%to 70 wt.%,corresponding to electrical conductivities from 1.86×10^(−7)to 1.85×10^(−5)S/*** a wide concentration range of absorbent for excellent microwave absorption is mainly attributed to the beneficial impedance matching properties of sea urchin-like aggregates of hollow nanotubes.A competitive absorption bandwidth of 3.36 GHz is achieved at 1 mm thickness,which can be broadened to 13.4 GHz by structural *** work shows a new scheme for designing reliable and practical microwave absorbers benefit from the wide absorbent concentration domain.

关键词： MnO_(2)nanotubes sea urchin-like aggregates broadband microwave absorption wide filling range

Aliphatic Segmented Poly（ether ester amide）s Synthesized from Hexanediamine, Sebacic Acid and Poly（ethylene glycol）s

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Chemical Research in Chinese Universities 2016年第3期32卷 505-511页

作者： ZHAO Yanping ZHAO Jingbo zhang Zhiyuan zhang junying Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beij'ing University of Chemical Technology Beijing 100029 P. R. China

High molecular weight aliphatic segmented poly（ether ester amide）s（PEEAs） were synthesized via melt polycondensation and chain extension. An oligomeric polyamide（PA） terminated mainly with -COOH groups（HOOC-PA-COOH） was prepared from the reaction of nylon 610 salt with sebacic acid. Melt polycondensation of HOOC-PA-COOH with polyethylene glycol（PEG）, such as PEG400, PEG600, PEG1000 and PEG1500, was conducted at 200 ℃, and several segmented PEEA prepolymers（PrePEEAs） were prepared. Chain extension of PrePEEAs was carried out at 190 ℃ using 2,2＇-（1,4-phenylene）-bis（2-oxazoline） and adipoyl biscaprolactamate as combination chain extenders. Chain extended PEEAs（ExtPEEAs） were characterized by gel permeation chromatography（GPC）, Fourier transform infrared spectrophotometer（FTIR）, proton nuclear magnetic resonance（1H NMR）, differential scanning calorimetry（DSC）, wide angle X-ray scattering（WAXS）, thermogravimetry analysis（TGA）, and tensile test. The ExtPEEAs exhibited Mn up to 98700, Tm from 164.2 ℃ to 176.1 ℃, initial decomposition temperature above 320.6 ℃, tensile strength up to 34.80 MPa, and strain at break from 111.92% to 353.12%. Aliphatic segmented PEEAs with good thermal and mechanical properties were prepared.

关键词： Copolymer Segmented Poly(ester amide) Polycondensation Chain extension

Integrated removal of NO and mercury from coal combustion flue gas using manganese oxides supported on TiO_2

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Journal of Environmental Sciences 2017年第3期29卷 141-150页

作者： Shibo zhang Yongchun Zhao Zonghua Wang junying zhang Lulu Wang Chuguang Zheng State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and Technology Henan Institute of Metallurgy Co. Ltd. Research Center of Quality Inspection Analysis and Test of Henan Academy of Sciences

A catalyst composed of manganese oxides supported on titania （MnOx/TiO2） synthesized by a sol-gel method was selected to remove nitric oxide and mercury jointly at a relatively low temperature in simulated flue gas from coal-fired power plants. The physico-chemical characteristics of catalysts were investigated by X-ray fluorescence （XRF）, X-ray diffraction （XRD）, and X-ray photoelectron spectroscopy （XPS） analyses, etc. The effects of Mn loading, reaction temperature and individual flue gas components on denitration and Hg0 removal were examined. The results indicated that the optimal MrgTi molar ratio was 0.8 and the best working temperature was 240℃for NO conversion. 02 and a proper ratio of [NH3]/[NO] are essential for the denitration reaction. Both NO conversion and Hg0 removal efficiency could reach more than 80% when NO and Hg0 were removed simultaneously using Mn0.8Ti at 240℃. Hg0 removal efficiency slightly declined as the Mn content increased in the catalysts. The reaction temperature had no significant effect on Hg0 removal efficiency. 02 and HCI had a promotional effect on Hg0 removal. SO2 and NH3 were observed to weaken Hg0 removal because of competitive adsorption. NO first facilitated Hg0 removal and then had an inhibiting effect as NO concentration increased without 02, and it exhibited weak inhibition of Hg0 removal efficiency in the presence of 02. The oxidation of Hg0 on MnOx/ TiO= follows the Mars-Maessen and Langmuir-Hinshelwood mechanisms.

关键词： ManganeseTitaniaNitric oxideMercurySCR

Photo-cured phase change energy storage material with photo-thermal conversion, self-cleaning and electromagnetic shielding performances via the lamellar structure strengthened by segment rearrangement of dynamic disulfide bond

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Journal of Materiomics 2024年第5期10卷 1049-1062页

作者： Ziyu Liu Yuhan Li Jue Cheng junying zhang Key Laboratory of Carbon Fiber and Functional Polymers Ministry of EducationBeijing University of Chemical TechnologyBeijing100029China

At present,phase change materials(PCMs)with single function hardly meet the needs of advanced intelligent materials in practical applications,and the multifunction integration is the current ***,photo-cured multifunctional PCMs are hampered by insufficient transparency due to adding functional fillers,such as carbon and metal *** novel strategy is necessary to overcome this ***,a photo-cured multifunctional PCM is prepared by using the design of a lamellar structure composing the photo-cured phase change polymer layer and the functional fillers *** curing of the phase change polymer is realized by the photo-induced"thiol-ene"click reaction,and reversible dynamic disulfide bonds are introduced into the PCM,which not only gives the phase change crosslinked network reprocessability,but also strengthens the interface layer by the chain rearrangement to form a stable composite *** carboxylated multiwalled carbon nanotubes(CCNTs)and silver nanowires(AgNWs),as functional fillers,give the PCM photo-thermal conversion,self-cleaning and electromagnetic shielding(EMI SE)*** phase change latent heat and photo-thermal conversion can reach 105.2 J/g and 78.5%,and the water contact angle is 142°with self-cleaning *** addition,due to the dense and well-developed conductive path formed by AgNWs layer on the PCM surface,the EMI SE effect can reach 39 dB with only 6.3%(in mass)filler content and 7.2%phase change latent heat *** far as we know,this is the first report about photo-cured PCMs with self-cleaning,photo-thermal conversion and EMI SE performances.

关键词： Photo-curing Phase change materials Lamellar structure Interface bonding Multifunctional integration

CO_2 Sequestration from flue gas by direct aqueous mineral carbonation of wollastonite

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Science China(Technological Sciences) 2013年第9期56卷 2219-2227页

作者： YAN Heng zhang junying ZHAO YongChun ZHENG ChuGuang State Key Laboratory of Coal Combustion Huazhong University of Science and Technology

Emission of carbon dioxide is considered to be the main cause of the greenhouse effect. Mineral carbonation, an important part of the CCS technology, is an attractive option for long-term CO2 sequestration. In this study, wollastonite was chosen as the feedstock and the feasibility of direct aqueous mineral carbonation in the simulated flue gas was investigated via a series of experimental studies carried in a stirred reactor. X-ray diffraction （XRD）, X-ray fluorescence spectroscopy （XRF）, ion chro- matography （IC） and thermal decomposition were used to determine the carbonation conversion. The influences of various factors, including reaction temperature, reaction pressure, solution composition, heat-treatment and particle size, were dis- cussed. Concurrently, the effects of SO2 and NO presented in simulated flue gas were also investigated and a possible mecha- nism was used to explain the results. Experimental results show that reaction temperature, reaction pressure and particle size can effectively improve the carbonation reaction. Addition of 0.6 M NaHCO3 was also proved to be beneficial to the reaction and heat-treatment is not needed for wollastonite to get a higher carbonation conversion. Compared with carbonation in puri- fied CO2 gas, CO2 sequestration directly from simulated flue gas by mineral carbonation is suggested to have a certain degree of economic feasibility in the conditions of medium and low-pressure. A highest carbonation conversion of 35.9% is gained on the condition of T=150℃, P=40 bar and PS 〈30 μ in distilled water for 1 h.

关键词： CO2 sequestration mineral carbonation wollastonite flue gas