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Diffusion bonding between nickel－base superalloy K24 and heat－resisting steel 1Cr11Ni2W2MoV

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China Welding 1996年第2期5卷 89-95页

作者： ZHANG Jie ZHANG Jiuhai HAN Wenbo and LI Zhuoran(Measuring and Analysis Center,School of Materials Science and Engineering, harbin Institute of Technology,harbin,150080.China)

The Vacuum diffusion bonding between nickel-base superalloy K24 and heatresisting steel 1Cr11Ni2W2MoV was studied and the effects of welding parameters,including bonding temperature T,pressure P,time t,vacuum V and interlayer thickness h ,on the microstructure and properties of the joint were *** optimum parameters for the diffusion bonding were found to be:T=1100￣1200℃,t=5￣30 MPa,V≥1×10-2 *** the welded specimens are tensioned at room temperature,ductile fracture takes place at the nickel-base superalloy part or at the joint and the tensile strength reaches 850 MPa,When the tensile tests are carried out at 500℃ ,all the bonded specimens fractured at heat-resisting steel part,and tensile strength is 750 *** interlayer thickness greatly affects the joint properties,and the interlayer thickness depends on the size of the bonded *** impeller of nickel-base superalloy K24 and shaft of heat-resisting steel 1Cr11Ni2MoV,which are used in aerospace engine,has been successfully jointed jointed by means of high frequency induction diffusion bonding.

关键词： superalloy heat-resisting steel diffusion bonding

Uniqueness and stability in an inverse problem for a Poisson's equation

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Science China Mathematics 2007年第7期50卷 967-976页

作者： Li-xin FENG~(1+) Yan-cheng QU~2 1 School of Mathematical Sciences,Heilongjiang University,harbin 150080,China 2 Research Center of Control and Inertial Technology,harbin Institute of Technology,harbin 150001,China School of Mathematical Sciences Heilongjiang University Harbin China Research Center of Control and Inertial Technology Harbin Institute of Technology Harbin China

Consider the Poisson’s equation Ψ″ (x) = ?e v?Ψ + e Ψ?v ? N(x) with the Dirichlet boundary data, and we mainly investigate the inverse problem of determining the unknown function N(x) from a parameter function fa... 详细信息

关键词： Poisson’s equation well-posedness inverse problem 65N30 35R30

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural Science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( College of Life and Environment Science, harbin Normal University, harbin 150080, China College of Resources Environment & Tourism, Capital Normal University, Beijing 100037, China College of Economics and Management, Northeast Agricultural University, harbin 150030, China) College of Life and Environment Science Harbin Normal University Harbin 150080 China College of Resources Environment and Tourism Capital Normal University Beijing 100037 China College of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

An Approximate Algorithm for a Class of Nonlinear Bilevel Integer Programming

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Systems Science and Systems Engineering 2002年第2期11卷 136-142页

作者： LI Lei, TENG Chun-xian, TIAN Guang-yue harbin University of Science and Technology, harbin, 150080, China harbin University of Science and Technology Harbin 150080 China

The algorithm for a class of nonlinear bilevel integer programming is discussed in this paper. It is based on the theory and algorithm for nonlinear integer programming. The continuity methods for integer programming are studied in this paper. After simulated annealing algorithm is applied to the upper-level programming problem and the thought of filled function method for continuous global optimization is applied to the corresponding lower-level programming, an approximate algorithm is established. The satisfactory algorithm is elaborated in the following example.

关键词： bilevel integer programming continuity methods simulated annealing filled function

The generalized solution of ill-posed boundary problem

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Science China Mathematics 2006年第7期49卷 902-911页

作者： CAO Weiping & MA Jipu Department of Mathematics and Physics, Huaihai Institute of Technology, Lianyungang 222005, China Y. Y. Tseng Functional Analysis Research Centre, harbin Normal University, harbin 150080, China Department of Mathematics and Physics Huaihai Institute of Technology Lianyungang China Y. Y. Tseng Functional Analysis Research Centre Harbin Normal University Harbin China

In this paper, we define a kind of new Sobolev spaces, the relative Sobolev spaces Wk,p0(Ω,∑). Then an elliptic partial differential equation of the second order with an ill-posed boundary is discussed. By utilizing the ideal of the generalized inverse of an operator, we introduce the generalized solution of the ill-posed boundary problem. Eventually, the connection between the generalized inverse and the generalized solution is studied. In this way, the non-instability of the minimal normal least square solution of the ill-posed boundary problem is avoided.

关键词： generalized inverse of operator, generalized solution, ill-posed boundary problem, elliptic partial differential equations of second order.

A Class of Genetic Algorithms on Bilevel Multi-objective Decision Making Problem

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Systems Science and Systems Engineering 2000年第3期10卷 290-296页

作者： TENG Chun\|xian,\ LI Lei,\ LI Hao\|bai harbin University of Science and Technology, harbin 150080, China

In this paper, it is discussed that the method on how to transform the bilevel multi objective decision making problem (BMDMP) into the equivalent generalized multi objective decision making problem. In order to better embody the decision maker′s hope and desire, we can transform it into the goal programming problem by means of genetic algorithms and obtain the goal optimization solution. The method which is satisfactory is elaborated in the following example.

关键词： multi objective decision making goal programming genetic algorithms

The　Learning　Control　and　Learning　Adaptive　Control　of　General　Nonlinear　Systems：MIMO　Case

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Systems Science and Systems Engineering 1996年第1期6卷 1-8页

作者： HOU Zhongsheng and HAN Zhigang(Institute of Applied Mathematics,Heilongjiang University,harbin 150080,China)

The learning control law for the general MIMO nonlinear systems with white noise distrubance is presented in the paper,it has extremely simple, recursive, incremental form,and strong robustness,it can also deal with the ill-conditioned *** new adaptive control scheme is presented when the parameters of the MIMO nonlinear systems are *** convergence,BIBO stability,and robustness of learning adaptive control scheme are also discussed in this paper.

关键词： MIMO nonlinear systems learning control learning adaptive control convergence BIBO stability robustness

INHIBITIVE ACTION OF INORGANIC COMPOUND ON CORROSION OF ALUMINIUM IN HYDROCHLORIC ACID

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Chinese Chemical Letters 1992年第1期3卷 75-76页

作者： Qing Hai CAI Bin LU Ling Fei CUI Department of Chemistry,harbin Normal University,harbin 150080

The inhibitive action of CaSO_4 towards corrosion of aluminium in 1 mol/L HCl has been inveetigated by using fluorometrio and weight loss *** results show that the inhibitor exhibits an outstanding function of inhibition,especially at higher tempe- ratures,and it was found to be predomiantly of cathodic rate *** mechanism of inhibition and the effect of CdSO_4 on the corrosion kinetics are also discussed.

关键词： ACTION INHIBITIVE ACTION OF INORGANIC COMPOUND ON CORROSION OF ALUMINIUM IN HYDROCHLORIC ACID

Photodecomposition of H_2S to H_2 over Cd_xZn_(1-x)S composite photocatalysts

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Rare Metals 2009年第2期28卷 137-141页

作者： Bai, Xuefeng Wu, Dan Wang, Peng School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Heilongjiang Institute of Petrochemistry Harbin 150040 China School of Chemistry and Material Science Heilongjiang University Harbin 150080 China

A series of CdxZn1-xS (x = 0.1-0.9) photocatalysts were prepared by coprecipitation. They could form solid solution semiconductors with hexagonal phase in agreement with pure CdS by characterization of XRD. The photophysical properties of CdxZn1-xS photocatalysts were measured by UV-Vis diffuse reflectance spectrum and surface photovoltage spectroscopy (SPS). The band gap energy gradually reduced with the increasing of x value in CdxZn1-xS,and when x = 0.7,the Cd0.7Zn0.3S photocatalyst had the strongest sur...

关键词： hydrogen production photodecomposition composite photocatalyst solid solution semiconductor