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Electrocatalytic response of poly(cobalt tetraaminophthalocyanine)/multi-walled carbon nanotubes-Nafion modified electrode toward sulfadiazine in urine

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第6期13卷 503-510页

作者： xiao-ping hong Yan ZHU Yan-zhen ZHANG Department of Chemistry Zhejiang UniversityHangzhou 310028China Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Stomatology the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China

A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(Co II TAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is *** electrode showed a very attractive performance by combining the advantages of Co II TAPc,MWCNTs,and *** with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode,the electrocatalytic activity of poly(Co II TAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential,high current responses,and good anti-fouling *** oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 μmol/L with the detection limit of 0.17 μmol/L.

关键词： Sulfadiazine Electrochemical detection Cobalt tetraaminophthalocyanine Multi-walled carbon nanotubes

Adaptive Coordinated Control for Hot Strip Finishing Mills

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Journal of Iron and Steel Research International 2011年第4期18卷 36-43页

作者： JIAO xiao-hong SHAO Li-ping PENG Yan Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 Hebei China Institute of Mechanical Engineering Yanshan University Qinhuangclao 066004 Hebei China

To further improve the control accuracy for strip dimension of hot strip mills,an adaptive control scheme is investigated for a hot strip finishing mill based on the decentralization and coordination among the controllers of gauge,tension and ***,the adaptive controller designed can regulate simultaneously the strip exit thickness,the strip tension and the looper angle to ensure better performance of the strip quality of finishing ***,the control scheme is proposed in consideration of the essential nonlinearity and the unavoidable friction phenomena in the mechanical system,so the controller can be efficient in a wider range of working *** simulation results of a model obtained from a real hot strip finishing mill show the effectiveness of the proposed control scheme in comparison with the conventional control method.

关键词： hot strip finishing mills exist gauge tension looper angle adaptive control

Leaf stable carbon isotope composition in Picea schrenkiana var. tianschanica in relation to leaf physiological and morphological characteristics along an altitudinal gradient

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Journal of Mountain Science 2016年第7期13卷 1217-1228页

作者： ZHANG Hui-wen WU Zhen xiao hong-lang State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research Institute Key Laboratory of Ecohydrology of Inland River Basin Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Western China’s Environmental Systems (Ministry of Education) Lanzhou University Lanzhou Institute of Seismology China Earthquake Administration

To understand the effects of leaf physiological and morphological characteristics on δ13C of alpine trees, we examined leaf δ13C value, LA, SD, LNC, LPC, LKC, Chla+b, LDMC, LMA and Narea in one-year-old needles of Picea schrenkiana var. tianschanica at ten points along an altitudinal gradient from 1420 m to 2300 m a.s.l. on the northern slopes of the Tianshan Mountains in northwest China. Our results indicated that all the leaf traits differed significantly among sampling sites along the altitudinal gradient(P<0.001). LA, SD, LPC, LKC increased linearly with increasing elevation, whereas leaf δ13C, LNC, Chla+b, LDMC, LMA and Narea varied non-linearly with changes in altitude. Stepwise multiple regression analyses showed that four controlled physiological and morphological characteristics influenced the variation of δ13C. Among these four controlled factors, LKC was the most profound physiological factor that affected δ13C values, LA was the secondary morphological factor, SD was the third morphological factor, LNC was the last physiological factor. This suggested that leaf δ13C was directly controlled by physiological and morphological adjustments with changing environmental conditions due to the elevation.

关键词： Alpine trees Leaf Carbon isotope composition Physiological characteristics Morphological characteristics Altitudinal variation

Ceramic-lined compound copper pipe prepared by SHS process

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 106-110页

作者： FU Han-guang JIANG Zhi-qiang ZHANG xiao-hong Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Industrial Engineering Zhengzhou Institute of Aeronautics Zhengzhou China Taiyuan Iron and Steel (Group) Company Taiyuan China

Self-propagating high-temperature synthesis(SHS) is a new kind of material synthesis technique, and has characteristics with respect to low energy consumption, short synthetizing time, high production quantity, high product purity and no environmental pollution. When SHS combines with centrifugal casting, ceramic-lined compound copper pipe(CLCCP) can be produced, the inner surface of copper pipe can produce ceramic coatings having good wear and corrosion resistance. In order to increase the densification degree, combining strength and toughness of ceramic layer, the effects of additives such as SiO2, CrO3, Na2B4O7 and ZrO2 are researched, adding SiO2 and CrO3 in thermite, the densification degree of ceramic layer increases, adding Na2 B4 O7 in thermite can increase combining strength, adding ZrO2 in thermite can increase the toughness of ceramic layer. CLCCP is used in tubular billet crystallizer, having excellent service effects and decreasing the production cost of tubular billet.

关键词： SHS ceramic lining compound copper pipe crystallizer

Semi-Fredholm Spectrum and Weyl＇s Theorem for Operator Matrices

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Acta Mathematica Sinica,English Series 2006年第1期22卷 169-178页

作者： xiao hong CAO Mao Zheng GUO Bin MENG College of Mathematics and Information Science Shanxi Normal University Xi'an 710062 P. R. China LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

When A ∈ B（H） and B ∈ B（K） are given, we denote by Mc an operator acting on the Hilbert space HΘ K of the form Me = （ A0 CB）. In this paper, first we give the necessary and sufficient condition for Mc to be an upper semi-Fredholm （lower semi-Fredholm, or Fredholm） operator for some C ∈B（K,H）. In addition, let σSF＋（A） = {λ ∈ C ： A-λI is not an upper semi-Fredholm operator} bc the upper semi-Fredholm spectrum of A ∈ B（H） and let σrsF- （A） = {λ∈ C ： A-λI is not a lower semi-Fredholm operator} be the lower semi Fredholm spectrum of A. We show that the passage from σSF±（A） U σSF±（B） to σSF±（Mc） is accomplished by removing certain open subsets of σSF-（A） ∩σSF＋（B） from the former, that is, there is an equality σSF±（A） ∪σSF± （B） = σSF± （Mc） ∪＆ where L is the union of certain of the holes in σSF±（Mc） which ilappen to be subsets of σSF- （A） A σSF＋（B）. Weyl＇s theorem and Browder＇s theorem are liable to fail for 2 × 2 operator matrices. In this paper, we also explore how Weyl＇s theorem, Browder＇s theorem, a-Weyl＇s theorem and a-Browder＇s theorem survive for 2 × 2 upper triangular operator matrices on the Hilbert space.

关键词： Semi-Fredholm operator Fredholm operator Spectrum Weyl's theorem

Numerical simulation of protection range in exploiting the upper protective layer with a bow pseudo-incline technique

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Mining Science and Technology 2009年第1期19卷 58-64页

作者： HU Guo-zhong WANG hong-tu LI xiao-hong FAN xiao-gang YUAN Zhi-gang Key Lab for Exploitation of China Southwestern Resources ＆ Environmental Disaster Control Engineering Ministry of Education Chongqing University Chongqing 400030 China

The developing processes of stress and deformation fields of a protected layer after mining an upper-protective layer with a bow pseudo-incline technique were simulated to locate the protection region. The pressure relief of the protected layer was analyzed after mining the upper-protective layer. The pressure relief angle along the strike and incline were located according to the roles of protection of the deformation and stress pressure-relief of the protective layer after mining. This results show that the upper-protective layer with the bow pseudo-incline technique have an upper and downside pressure relief angle of 85 and 68 degrees respectively; the distribution of strike pressure relief angles along the pseudo-incline working face is uneven and their values range from 38.3 to 51 degrees. The pressure relief angle of the inclined middle location was the largest. The distribution of the protection region of the upper-protective layer with the bow pseudo-incline teelmique located by practical tests and numerical simulation is essentially consistent, compared with the results obtained by these methods.

关键词： bow pseudo-incline technique upper-protective layer protection region 3D numerical simulation

Resonant Peak Splitting for Ballistic Conductance in Two-Dimensional Electron Gas Under Electromagnetic Modulation

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Chinese Physics Letters 2000年第8期17卷 598-600页

作者： WANG Ru-Zhi YAN xiao-hong Department of Physics Xiangtan UniversityXiangtan 411105

By developing a transfer-matrix method,the resonant peaks splitting of ballistic conductance are investigated into the two-dimensional electron gas system with both electric and magnetic modulations of nanoscale *** is found that there exists the n-fold resonant peak splitting for ballistic conductance through n perpendicular magnetic barriers to n electric *** a combination of m magnetic barriers and n electric barriers by increasing the amplitude of electric field,the folds of the splitting would shift from m- to n-1.

关键词： splitting resonant conductance

Characteristics of metal flow in cold extrusion under electric-hydraulic chattering

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Journal of Iron and Steel Research International 2017年第2期24卷 138-146页

作者： Zhi-heng Wang Wei-tao Zhan xiao-xiao hong Guan-jun Bao Qing-hua Yang Key Laboratory of E&M Zhejiang University of Technology Hangzhou 310032 Zhejiang China

An experimental setup for cold extrusion process with electric-hydraulic chattering was developed and its working principle was introduced. The finite element （FE） model for a kind of cup part （material： 20Cr） was built by using the software Deform-3D. FE simulation experiments with and without electric-hydraulic chattering were carried out to analyze the velocity fields and the metal grid flow lines. The extrusion ex- periments of the cup part were also performed under different conditions. The difference of metal flow lines with and without electric-hydraulic chattering was discussed via a scanning electron microscope （SEM） and the Keyence super-depth three-dimensional microscopic system. The results showed that with the electric-hydraulic chattering, the velocity of material flow increases, whereas deformation resistance decreases. Electric hydraulic chattering results in easy metal flow, small bending degree of metal flow lines, slender and dense metal grains, and thereby an improved quality of the deformed parts.

关键词： Cold extrusion Electric-hydraulic chattering Finite element analysis Material flow

Non-linear relationship between combustion kinetic parameters and coal quality

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第5期13卷 344-352页

作者： Jian-guo YANG xiao-long ZHANG hong ZHAO Li SHEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

Combustion kinetic parameters(i.e.,activation energy and frequency factor) of coal have been proven to relate closely to coal properties;however,the quantitative relationship between them still requires further *** paper adopts a support vector regression machine(SVR) to generate the models of the non-linear relationship between combustion kinetic parameters and coal *** analyses on the thermo-gravimetry(TG) data of 80 coal samples were performed to prepare training data and testing data for the *** models developed were used in the estimation of the combustion kinetic parameters of ten testing *** predicted results showed that the root mean square errors(RMSEs) were 2.571 for the activation energy and 0.565 for the frequency factor in logarithmic form,*** curves defined by predicted kinetic parameters were fitted to the experimental data with a high degree of precision.

关键词： Kinetic parameter Coal property Thermo-gravimetry(TG) Support vector regression machine(SVR) Differential evolution