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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

Synthesis and Heavy Metal Immobilization Behaviors of Fly Ash based Gepolymer

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Journal of Wuhan university of Technology(materials science) 2009年第5期24卷 819-825页

作者：张云升 Jiangsu Civil engineering materials Key laboratory Southeast University

Two aspects of studies were carried out： 1） synthesis of geopolymer by using fly ash and metakaolin; 2） Immobilization behaviors of fly ash based geopolymer in a presence of Pb and Cu ions. As for the synthesis of fly ash based geopolymer, 4 different fly ash content （10%, 30%, 50%, 70%） and 3 types of curing regimes （standard curing, steam curing and autoclave curing） were investigated to obtain the optimum synthesis condition based on the compressive and flexural strength. The experimental results show that geopolymer, containing 30% fly ash and synthesized at steam curing （80 ℃ for 8 h）, exhibits higher mechanical strengths. The compressive and flexural strengths of fly ash based geopolymer reach 32.2 MPa and 7.15 MPa, respectively. Additionally, Infrared （IR） and X-ray diffraction （XRD） techniques were used to characterize the microstructure of the fly ash geopolymer. IR spectra shows that the absorptive band at 1086 cm^-1 shifts to lower wave number around 1033 cm^-1, and the 6-coordinated Al transforms into 4-coordination during the syn-thesis of fly ash based geopolymer. The resulting geopolymeric products were X-ray amorphous materials. As for immobilization of heavy metals, the leaching tests were employed to investigate the immobilization behaviors of the fly ash based geopolymer synthesized under the above optimum condition. The leaching tests showed that fly ash based geopolymer can effectively immobilize Cu and Pb heavy metal ions, and the immobilization efficiency reached 90% greater when heavy metals were incorporated in the fly ash geopolymer in the range of 0.1% to 0.3%. The Pb exhibits better immobilization efficiency than the Cu, especially in the case of large dosages of heavy metals.

关键词： geopolymer fly ash synthesis immobilization heavy metals

Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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science china Chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2 & SHI TongShun2 1 college of materials science and engineering, Shandong university of Technology, Zibo 255049, china 2 Department of Chemistry, Jilin university, Changchun 130023, china college of materials science and engineering Shandong University of Technology Zibo China Department of Chemistry Jilin University Changchun China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12 kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Large eddies induced by local impulse at wall of boundary layer with pressure gradients

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Progress in Natural science:materials International 2008年第7期18卷 873-878页

作者： Changgen Lu a,b,*, Weidong Caob, Yanmei Zhang b, Jintao Pengb a college of Atmospheric science, nanjing university of Information science & Technology, nanjing 210044, china b college of Environmental science and engineering, Hohai university, nanjing 210098, china college of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 China college of Environmental science and engineering Hohai University Nanjing 210098 China

Large eddies induced by local impulse at the wall with pressure gradients in the boundary layer was studied by direct numerical sim- ulations. The results show that the amplitude evolution, the high and low speed stripes, the formation of streamwise vortices, the ejection and sweeping, inflexions and distortion at the mean velocity profiles, as well as other characteristics, are consistent with the experimental and other numerical results. It is also found that large eddies are easy to be excited with adverse pressure gradient in the boundary layer, and the growth of amplitudes, formation of streamwise vortices and the influencing area etc., are much larger than those with favorable pressure gradient in the boundary layer. In contrast, large eddies are hardly to be induced through local impulse disturbance at the wall with favorable pressure gradients in the boundary layer.

关键词： Boundary layer Pressure gradients Impulse Large eddies

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

Controlled free radical polymerization of styrene initiated from the alkoxyamine-functionalized silicon surface

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science china Chemistry 2005年第5期48卷 449-458页

作者： CHEN Zhijun1, ZHOU Sikai1, LU Wenzhong1, FANG Shaoming1, JIANG Xiqun2 & YANG Changzheng2 1. college of materials and Chemical engineering, Zhengzhou university of Light Industry, Zhengzhou 450002, china 2. Laboratory of Mesoscopic Material science and Department of Polymer science & engineering, college of Chemistry & Chemical engineering, nanjing university, nanjing 210093, china college of materials and Chemical engineering Zhengzhou University of Light Industry Zhengzhou China Laboratory of Mesoscopic Material science and Department of Polymer science & engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing China

We describe a new method of fabricating a brush-like polystyrene layer anchored on the surface of the silicon substrate, which involves three steps, namely (i) the attachment of 3-methacryloxypropyltrimethoxysilane onto the silicon surface; (ii) the reaction of vinyl moiety at another extremity of the anchored 3-methacryloxypropyltrimethoxysilane to 4-Hydroxyl-2, 2, 6, 6-tetramethyl-1-piperidinyloxy (HTEMPO?) catalyzed by azobisisobutyronitrile (AIBN); (iii) living free radical grafting polymerization of styrene in the presence of HTEMPO?. The controllable living free radical polymerization permits accurate control of both the molecular weight and the polydispersity. X-photoelectron spectroscopy measurement proved that the alkoxyamine initiator layer forms on the silicon surface. XPS and Ellipsometry measurements showed that the poly-styrene chains were covalently anchored onto the silicon surface. The thickness of the grafted polymer layer can be accurately manipulated by altering the polymerization time. The new method allows synthesizing random copolymer and block copolymers by the sequential growth of monomers from the substrate surface.

关键词： polymer brush, controlled living free radical polymerization, thickness, atomic force microscopy, 3-methacryloxypropyltrimethoxysilane.

Preparation and properties of AZO thin films on different substrates

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Progress in Natural science:materials International 2010年第1期20卷 44-48页

作者： Hong-lie SHEN,Hui ZHANG,Lin-feng LU,Feng JIANG,Chao YANG college of materials science and engineering, nanjing university of Aeronautics and Astronautics,nanjing 210016,china college of materials science and engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Al doped ZnO(AZO)films were deposited on glass,polyethylene naphthalate(PEN)and polyethylene terephthalate(PET) at room temperature by radio frequency magnetron *** structural,surface morphology,electrical and optical properties of the AZO films were characterized by X-ray diffractometry(XRD),atomic force microscopy(AFM),Hall effect measurement and ultraviolet-visible spectrometer,*** films exhibit highly c-axis preferred orientation,and AZO film on glass exhibits compressive stress while that on plastic substrates presents tensile *** electrical property of the AZO film on glass is the best among the films on three kinds of *** value of the figure of merit for the AZO film on PEN is much better than that of the AZO film on PET and is close to that of AZO on glass in the wavelength range of 500-900 nm.

关键词： AZO magnetron sputtering electrical and optical property plastic substrate glass substrate

Adaptive recurrent-functional-link-network control for hypersonic vehicles with atmospheric disturbances

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science china(Information sciences) 2011年第3期54卷 482-497页

作者： DU YanLi 1, WU QingXian 2 , JIANG ChangSheng 2 & XUE YaLi 2 1 college of Astronautics, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 2 college of Automation engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china college of Astronautics Nanjing University of Aeronautics and Astronautics Nanjing China college of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing China

The controller design for a near-space hypersonic vehicle (NHV) is challenging due to its plant uncertainties and sensitivity to atmospheric disturbances such as gusts and turbulence. This paper first derives 12 states equations of NHVs subjected to variable wind field, and presents a novel recurrent neural network (RNN) control method for restraining atmospheric disturbances. The method devises a new B-spline recurrent functional link network (BRFLN) and combines it with the nonlinear generalized predictive control (NGPC) algorithm. Moreover, the proportional-derivative (PD) correction BRFLN is proposed to approximate atmo- spheric disturbances in flight. The weights of BRFLN are online tuned by the adaptive law based on Lyapunov stability theorem. Finally, simulation results show a satisfactory performance for the attitude tracking of the NHV in the mesosphere, and also illustrate the controller's robustness to wind turbulence.

关键词： near-space hypersonic vehicle atmospheric disturbances nonlinear predictive control adaptive control B-spline recurrent functional link network

MI-QSAR models for prediction of corneal permeability of organic com-pounds

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Acta Pharmacologica Sinica 2006年第2期27卷 193-204页

作者： Cheng CHEN Jie YANG~2 State Key Laboratory of Pharmaceutical Biotechnology,college of Life science,nanjing university,nanjing 210093,china State Key Laboratory of Pharmaceutical Biotechnology College of Life Science Nanjing University Nanjing China

Aim:To derive a theoretical model for the prediction of corneal permeability ofmiscellaneous organic compounds in drug ***:A training set of 28structurally diverse compounds was used to build up the membrane-interactionquantitative structure-activity relationship(MI-QSAR)*** intramolecular solute descriptors were computed using molecular mechanics,molecular dynamics simulations and quantum *** QSAR models wereoptimized using multidimensional linear regression fitting and a stepwise method.A test set of 8 compounds was evaluated using the models as part of a ***:Significant MI-QSAR models(R=0.976,S-0.1301,F=70.957)ofcorneal permeability of organic compounds were *** permeabil-ity was found to depend upon the sum of net atomic charges of hydrogen atomsattached to the heteroatoms(N,O),the sum of the absolute values of the netatomic charges of oxygen and nitrogen atoms,the principal moment of inertia(X),the Connolly accessible area and the conformational flexibility of the solute-mem-brane ***:The MI-QSAR models indicated that the cornealpermeability of organic molecules was not only influenced by the organic solutesthemselves,but also related to the properties of the solute-membrane complex,that is,the interactions of the molecule with the phospholipid-rich regions ofcellular membranes.

关键词： cornea permeability quantitative structureactivity relationship theoretical models