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Science china Chemistry 2008年第2期51卷 120-127页

作者： WEI RuiPing1,2, GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical engineering, college of Chemistry and Chemical engineering, nanjing Uni- versity of technology, nanjing 210009, china 2 college of Chemistry and Chemical engineering, Southeast university, nanjing 211189, china State Key Laboratory of Materials-Oriented Chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China college of Chemistry and Chemical engineering Southeast University Nanjing China

The bimetal-bearing (CePt or LaPt) 12-tungstophosphoric acid (H3PW12O40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2-chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 250℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%.

关键词： hydroisomerization of n-heptane bimetal catalyst heteropoly acid USY platinum

On the general expressions of finite Hankel transform

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2125-2130页

作者： JIANG Quan 1,2 & GAO CunFa 1 1 college of Aerospace engineering,nanjing university of Aeronautics and Astronautics,nanjing 210016,china 2 School of civil engineering,Nantong university,Nantong 226019,china college of Aerospace engineering Nanjing University of Aeronautics and Astronautics Nanjing China School of civil engineering Nantong University Nantong China

The general expressions of finite Hankel transform are naturally deduced with the help of the property of Bessel *** equations in this paper can degenerate into three kinds of boundaries since all the coefficients in the boundary conditions are taken into *** results can be adopted in solving physics problems involving the finite Hankel transform.

关键词： hankel transform bessel function finite integral

Resolution method for overlapping peaks based on the fractional-order differential

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Science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 college of Information & Control, nanjing university of Information Science & technology, nanjing 210044, china 2 college of Automation engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china college of Information & Control Nanjing University of Information Science & Technology Nanjing China college of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

Web Application Comprehension Based on Dependence Analysis

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Wuhan university Journal of Natural Sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2 , XU Bao-wen 1 , JIANG Ji-xiang 1 1.Department of Computer Science and engineering, Southeast university, nanjing 210096, Jiangsu, china 2.college of Computer Science and engineering, nanjing university of technology, nanjing 210009, Jiangsu , china Department of Computer Science and engineering Southeast University Nanjing Jiangsu China college of Computer Science and engineering Najing University of Technology Nanjing Jiangsu China

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 311 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (60373066, 60303024). National Grand Fundamental Research 973 Program of china (2002CB312000) and National Research Foundation for the Doctoral Program of Higher Education of chinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing

Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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Science china(Technological Sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2 1 Department of Materials Science and engineering,nanjing university of Science and technology,nanjing 210094,china 2 college of Materials Science and engineering,Southeast university,nanjing 211189,china Department of Materials Science and engineering Nanjing University of Science and Technology Nanjing China college of Materials Science and engineering Southeast University Nanjing China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB_3-type hydrogen storage alloy electrodes

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Science china(Technological Sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2,WU YaoMing1,MA LiQun2,SHEN XiaoDong2 & WANG LiMin1 1 State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,C hangchun 130022,china 2 college of Material Science and engineering,nanjing university of technology,nanjing 210009,china State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China college of Material Science and engineering Nanjing University of Technology Nanjing China

The(La0.67Mg0.33)1-xTixNi2.75Co0.25(x = 0,0.05,0.10,0.15 and 0.20,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 1200 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

Study on design pressure of in-service welding pipes

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Science china(Technological Sciences) 2006年第4期49卷 434-444页

作者： XUE Xiaolong1, ZHU Jiagui2 & SANG Zhifu1 1. college of Mechanical and Power engineering, nanjing university of technology, nanjing 210009, china 2. nanjing Yangzi Petrochemical Maintenance and Installation Co. Ltd., nanjing 210048, china college of Mechanical and Power engineering Nanjing University of Technology Nanjing China nanjing Yangzi Petrochemical Maintenance and Installation Co. Ltd. Nanjing China

A method of predicting design pressure and burn-through of in-service welding pipes was established. Temperature distributions of in-service welding under variable parameters were simulated by FEM. The effect of flowing of internal media was regarded as forced convection. Based on the numerical results, design pressure of the pipe can be obtained and burn-through can be predicted. It can be concluded that the design pressure decreases with the increasing of heat input. RSF and design pressure of the pipe increase with the increasing of flow rate. There is a range in which the increase changes greatly. For in-service welding, the range should be considered adequately to determine operating condition optimally. RSF increases with the increasing of pipe wall thickness. While the thickness increases to an extent, RSF shows little increase. Accord- ing to the curves of design pressure versus different parameters, safe working pressure can be achieved.

关键词： in-service welding, heat input, flow rate, pipe wall thickness, design pressure.

A NOVEL INTERPRETATION OF CONCENTRATION DEPENDENCE OF VISCOSITY OF DILUTE POLYMER SOLUTION

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Chinese Journal of Polymer Science 2000年第1期18卷 57-67页

作者： Yan Pan Rong-shi Cheng college of Material Science and engineering, South china university of technology, Guangzhou 510641, china college of Chemistry and Chemical engineering, nanjing university, nanjing 210093, china 华南理工大学广东广州

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence

NMR Research on Cement Clinker and Its Structures in Early Age Hydration

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Journal of Wuhan university of technology(Materials Science) 2011年第5期26卷 972-977页

作者：王晓钧 college of Materials Science and engineering Nanjing University of Technology

Clinker has long been regarded as a critical factor for cement hydration and solidification.α-C2S and β-C2S in 2CaO·SiO2（C2S） phase and C3S Monoclinic 1（C3S M1） and C3S Monoclinic 3 （C3S M3） in 3CaO·SiO2 （C3S） phase were clearly recorded in the 29Si MAS NMR *** content of C3S phase in the clinker deduced from the fine peak analysis coincides with the phase quantification analysis calculated by the Taylor-Bogue method based on XRF,which also accords to the statistical data in industrial *** provides a proof that C3S M1 and β-C2S phases have a prior reaction in the early age hydration of clinker,and demonstrates that aluminum coordination changes from tetracoordinated 4CaO·Al2O3·Fe2O3（C4AF） to hexacoordinated [Ca2Al（OH）6]（SO4）0.3·3H2O（Aft） in one day hydration and changes to the 3CaO·Al2O3·CaSO4·nH2O （Afm） in a seven-day hydration.

关键词： NMR clinker cement hydration

Electromagnetic and microwave absorbing properties of W-type barium ferrite doped with Gd^(3+)

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Rare Metals 2011年第1期30卷 44-48页

作者： HUANG Xiaogu CHEN Jiao WANG Lixi ZHANG Qitu college of Materials Science and engineering Nanjing University of Technology Nanjing 210009 China Jiangsu Provincial Key Laboratory of Inorganic and Composite New Materials Nanjing University of Technology Nanjing 210009 China

W-type barium ferrites doped with Gd^3＋,Ba1-xGdx（Zn0.3Co0.7）2Fe16O27（x = 0,0.05,0.10,0.15,0.20）,were prepared by a sol-gel *** effects of Gd^3＋ substitution on their microstructure,electromagnetic properties and microwave absorptive behavior were *** XRD patterns showed the single phase of W-type barium ferrite when x ≤ *** electromagnetic properties of samples were studied at the frequency range from 2 GHz to 18 GHz using a network analyzer（Agilent 8722ET）.The complex permittivity ε（ε＇,ε＇＇） increased gradually when x ≤ 0.10,but it decreased as x = *** real permeability（μ＇） decreased with the increase of Gd^3＋ content,while the imaginary permeability（μ＇＇） increased when x ≤ *** these reasons were discussed using the electromagnetic ***,the ferrite-epoxy compound coating materials with 80 wt.% of Ba0.9Gd0.1（Zn0.3Co0.7）2Fe16O27 were prepared to measure the microwave absorbing *** maximum of reflection loss（RL） reached about-27 dB and RL was below-10 dB in the frequency range of 8-18 GHz when the thickness was 1.92 mm.

关键词： nonmetallic material barium compounds ferrite sol-gel process materials properties doping