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Heat treatment of novel low-carbon multi-alloyed anti-wear marine steel

Progress in Natural Science:Materials International 2011年第3期21卷 254-261页

作者： Jing-hua JIANG~(1,2),Qiu-yue WANG~1,Ai-bin MA~(1,2),Jun SHI~1,Liu-yan ZHANG~1, Hui-dong YANG~(2,3),Fu-min LU~2,Qi ZHOU~2 1.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai university,Nanjing 210098,China 2.College of Mechanics and Materials,Hohai university,Nanjing 210098,China 3.department of Mechanical and Aerospace Engineering,north Carolina State university, Raleigh,north Carolina 27695-7919,usa National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China College of Mechanics and Materials Hohai University Nanjing 210098 China department of Mechanical and Aerospace Engineering North Carolina State University Raleigh North Carolina 27695-7919 USA

A low-carbon anti-wear steel,multi-alloyed with Si-Cr-Mn-Al-Ni-Mo-（Nb,RE）,was designed for vane pumps of ships. The novel cast steel after various heat treatments was characterized by microstructure observations and mechanical properties measurement in order to achieve an optimal process correlated with good abrasive resistance for a long marine *** scanning calorimetry and hardness analyses deduced a complete austenitizing temperature of 1 000℃,based on the alloying element homogenization and defective structure elimination without grain *** optimal austempering process（austenitized at 1 000℃,quick cooled for holding at 350℃for 1.5 h and then air-cooled to room temperature） produced a uniform mixture structure of fine carbide-free aciculate bainites and few lath martensites,resulting in the tensile strength increase of 34%and impact toughness increase of 50%compared with that of the as-cast *** abrasive wheel tests show that the austempered steel has good wear resistance with a mass-loss rate of 170 mg/（km·cm2） under applied load of 70 N in acidic *** new grade steel （containing anti-corrosion elements of Cr and rare earth） can find wide application in marine engineering,with further enhanced comprehensive properties via melting process improvement.

关键词： abrasive resistance carbide-free bainite marine steel mechanical performance heat treatment

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Oxides for High Temperature Superconductivity and Beyond

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Tsinghua Science and Technology 1998年第1期3卷 57-78页

作者： Ching Wu Chu department of Physics and texas Center for Superconductivity, university of Houston, Houston, tx 77204, usa

In this paper, I shall briefly summarize the present state of high temperature superconductivity research and development together with an assessment of the prospect of yet a higher transition temperature and an outline of challenges facing today's practitioners of high temperature super conductivity science and technology. The extensive knowledge acquired in the last decade in high temperature superconducting science and materials may usher in a new era of material engineering, which I would like to call mesomaterial engineering for the fabrication of perovskite and related oxide superlattices, a new class of materials for science and technology. Therefore, I shall also present the rationale behind this effort and the promises of the new materials, together with a list of several preliminary successful examples.

关键词： high temperature superconductivity oxide mesomaterial engineering

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Polynomials,Higher Order Sobolev Extension Theorems and Interpolation Inequalities on Weighted Folland-Stein Spaces on Stratified Groups

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Acta Mathematica Sinica,English Series 2000年第3期16卷 405-444页

作者： Guozhen Lu department of Mathematics,Wayne State university,Detroit,MI 48202,usa department of Mathematics Wayne State University Detroit USA

This paper consists of three main *** of them is to develop local and global Sobolev interpolation inequalities of any higher order for the nonisotropic Sobolev spaces on stratified nilpotent Lie *** the extensive research after Jerison’s work[3]on Poincaré-type inequalities for Hrmander’s vector fields over the years,our results given here even in the nonweighted case appear to be *** interpolation inequalities have crucial applications to subelliptic or parabolic PDE’s involving vector *** main tools to prove such inequalities are approximating the Sobolev func- tions by polynomials associated with the left invariant vector fields on *** very useful properties for polynomials associated with the functions are given here and they appear to have independent interests in their own *** the existence of such polynomials is the second main part of this *** results of these two parts have been announced in the author’s paper in Mathematical Research Letters[38]. The third main part of this paper contains extension theorems on anisotropic Sobolev spaces on stratified groups and their applications to proving Sobolev interpolation inequalities on(εδ)domains. Some results of weighted Sobolev spaces are also given *** construct a linear extension operator which is bounded on different Sobolev spaces *** particular,we are able to construct a bounded linear extension operator such that the derivatives of the extended function can be controlled by the same order of derivatives of the given Sobolev *** are stated and proved for weighted anisotropic Sobolev spaces on stratified groups.

关键词： Poincaré inequalities Extension theorems Interpolation inequalities Anisotropic Sobolev spaces A_p weights (ε,δ)domains Vector fields Polynomials on stratified groups

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Isoprenaline enhances local Ca2+ release in cardiac myocytes

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Acta Pharmacologica Sinica 2006年第7期27卷 927-932页

作者： Jian-xin SHEN~(2,3,42 department of Physiology,Shantou university Medical College,Shantou 515041,China 3 department of Physiology,Medical School of Xi'an Jiaotong university,Xi'an 710061,China department of Physiology Shantou University Medical College Shantou China department of Physiology Medical School of Xi'an Jiaotong University Xi'an China

Aim:Contraction of cardiac myocytes is controlled by the generation and ampli-fication of intracellular Ca2+*** key step of this process is the couplingbetween sarcolemma L-type Ca2+channels（LCCs）and ryanodine receptors（RyRs）in the sarcoplasmic reticulum（SR）.β-Adrenergic stimulation is an important regu-latory mechanism for this coupling *** the details underlied the globallevel,which require local Ca2+release study are still *** present study isto explore the effects of β-adrenergic stimulation on local Ca2+***:Using confocal microscopy combined with loose-seal patch-clamp approaches,effects of isoprenaline(1 μmol·L-1),a β-adrenergic agonist,on local SR Ca2+re-lease triggered by Ca2+influx through LCCs in intact rat cardiac myocytes ***:Isoprenaline increased the intensity of ensemble averagedlocal Ca2+transients,the peak of which displayed a typical bell-shaped voltage-dependence over the membrane voltages ranging from～-40mV to～+35m ***-ther analysis showed that this enhancement could be explained by the increasedcoupling fidelity（which refers the increased probability of RyRs activation upondepolarization）,and the increased amplitude of evoked Ca2+sparks(due to moreCa2+releases through local RyRs).In addition,isoprenaline decreased the firstlatency,which displayed a typical"U"-shaped voltage-dependence,showing theavailable acceleration and synchronization of β-adrenergic stimulation on intrac-ellular calcium ***:Isoprenaline enhances local Ca2+release incardiac *** results underscore the importance of regulation of β-adrenergic stimulation on local intermolecular signals between LCCs and RyRs inheart cells.

关键词： local calcium release calcium signaling cardiac myocytes isoprenaline confocal microscopy

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The Crystal and Molecular Structure of a New Macrocyclic Ligand, (H_6BDBPH)Br_6·4H_2O

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Chinese Journal of Structural Chemistry 2000年第5期19卷 334-337页

作者： SHANGGUAN Guo\|Qiang (department of Chemistry, Jining Medical College, Jining 272013) [WT4”BZ]Arthur E. Martell Zhongren Zhang Joseph Reibenspies (department of Chemistry, texas A&M university, College Station, texas 77842, usa) 济宁医学院山东济宁 2 72 0 1 3 texas A&M university 美国 Texas 77842

The hexahydro\|bromide salt of a new 24\|membered hexaaza diphenol macrocyclic ligand, （H6BDBPH）Br6·4H2O （C 26H 56N6O6Br6, Mr= 1028.23）, crystallizes in the monoclinic system, space group P21/c, with cell parameters: a=14.441（5）, b=11.482（4）, c=12.090（6）, β=96.92°, V= 1990 （1）3, Z=2, Dc=1.716 g/cm3; F（000） =1024. MoKα radiation, λ= 0.71013), R = 0.0643 and wR = 0.1356 for 3507 independent reflections with I>2σ（I）. The macrocyclic ligand adapts chair form, and the crystallographic inversion center is located in the macrocyclic cavity, and the six bromide ions and four water molecules are situated symmetrically outside the macrocyclic cavity.

关键词： macrocyclic ligand synthesis crystal structure

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Multifractal modelling and spectrum analysis: Methods and applications to gamma ray spectrometer data from southwestern Nova Scotia, Canada

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Science China Earth Sciences 2006年第3期49卷 283-294页

作者： CHENG Qiuming1,2 1. State Key Lab of Geological Processes and Mineral Resources, China university of Geosciences, Wuhan 430074, China 2. department of Earth and Space Science and Engineering, department of geography, York university, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada State Key Lab of Geological Processes and Mineral Resources China University of Geosciences Wuhan China department of Earth and Space Science and Engineering Department of Geography York University Toronto Canada

Multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2 nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. Moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern Nova Scotia, Canada. The results have shown that the values of uranium (U), thorium (Th) and potassium (K) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios U/K and U/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for U, Th, K, U/Th and U/K consistently show two distinct power-law relationships for two ranges of wave number 12≤ω ≤160 km and 0≤ω ≤12 km. These properties might provide usefu

关键词： gamma ray spectrometer data, gold mineralization, alteration zones, multifractal modelling, spectral analysis, GIS.

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SYNTHESIS AND BIOTECHNOLOGICAL APPLICATIONS OF VINYL POLYMERINORGANIC HYBRID AND MESOPOROUS MATERIALS

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Chinese Journal of Polymer Science 2000年第1期18卷 1-7页

作者： Yen Wei Kun-yuan Qiu department of Chemistry, Drexel university, Philadelphia, Pennsylvania 19104, usa department of Polymer Science and Engineering, Peking university, Beijing 100871, China Drexel university 美国北京大学高分子科学与工程系北京

We describe the sol-gel synthesis of a new family of organic-inorganic hybrid materials, in which various vinyl polymers are covalently bonded to and uniformly distributed in inorganic oxide matrices. The materials can be tailored to have both good toughness and hardness while maintaining excellent optical transparency. Doping the sol-gel metal oxides with optically active compounds such as D-glucose results in new optical rotatory composite materials. Removal of the dopant compounds from the composites affords mesoporous oxide materials; which represents a new, nonsurfactant-templated route to mesoporous molecular sieves. We have successfully immobilized a series of enzymes and other bioactive agents in mesoporous materials. Catalytical activities of the enzyme encapsulated in mesoporous materials were found to be much higher than those encapsulated in microporous materials.

关键词： vinyl polymer-inorganic hybrid materials mesoporous materials sol-gel process biotech-nological applications

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POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 187-200页

作者： WAN DAQING(department of Mathematics, university of California, Irvine, CA 92697-3875, usa.) department of Mathematics University of California Irvine CA 92697-3875 USA

A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.

关键词： Pole Zeta function Complete intersection

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A preliminary analysis of arcuate structures-relationship of the island arc and deep-sea trench to the dip angle of Benioff zone

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Acta Oceanologica Sinica 1989年第1期8卷 125-136页

作者： Wu Lun, Liang Haihua, Ren Fuhu and Li Maosong The department of geography, Peking university, Beijing, China The department of Geology, Peking university, Beijing, China China

The origin of arcuate islands and deep-sea trenches has been studied for a long time and various interpretations have been proposed. In this paper, some analytical models are put forward from a geometrical viewpoint and then the theoretical dip angles of the underthrusting slabs of circum-Pacific island arcs are computed and compared with those of the Benioff zone. As a result, it is found that the dip angle of the underthrusting slab is one of the main factors determining the curvature of the arcuate structure. The authors consider that this result may contribute to the plate theory.

关键词： A preliminary analysis of arcuate structures-relationship of the island arc and deep-sea trench to the dip angle of Benioff zone deep

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MINIMIZING A LINEAR FRACTIONAL FUNCTION SUBJECT TO A SYSTEM OF SUP-T EQUATIONS WITH A CONTINUOUS ARCHIMEDEAN TRIANGULAR NORM

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Journal of Systems Science & Complexity 2009年第1期22卷 49-62页

作者： Pingke LI Edward P.Fitts department of Industrial and Systems Engineering,north Carolina State university,Raleigh,NC 27695-7906,US Shu-Cherng FANG Edward P.Fitts department of Industrial and Systems Engineering,north Carolina State university,Raleigh,NC 27695-7906,usa department of Mathematical Sciences,Tsinghua university,Beijing 100084,China College of Management,Dalian university of Technology,Dalian 116024,China. Edward P. Fitts department of Industrial and Systems Engineering North Carolina State University Raleigh USA department of Mathematical Sciences Tsinghua University Beijing China College of Management Dalian University of Technology Dalian China

This paper shows that the problem of minimizing a linear fractional function subject to asystem of sup-T equations with a continuous Archimedean triangular norm T can be reduced to a 0-1linear fractional optimization problem in polynomial ***,parametrization techniques,e.g.,Dinkelbach's algorithm,can be applied by solving a classical set covering problem in each *** reduction can also be performed on the sup-T equation constrained optimization problems withan objective function being monotone in each variable *** method could be extended aswell to the case in which the triangular norm is non-Archimedean.

关键词： Fractional optimization fuzzy relational equations triangular norms.

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