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Journal of Materials Science & Technology 2001年第5期17卷 579-580页

作者： Research Notes H.Suto Tohoku University, Aoba-Hachiman 5-4-12, Sendai, 980-0871, Japan Tohoku Univ Sendai Miyagi 9800871 Japan

Ultrahigh-strength mortar mixed surface-oxidized silicon carbide as a fine aggregate was prepared by means of press-casting followed by curing in an autoclave. The relation between modulus of elssticity up to 111 GPa and compressive strength up to 360 MPa of mortar mixed silicon carbide was discussed and it was revealed that the contributions of the aggregate hardness and of the interfacial strength between the aggregate and the cement paste on the elasticity of mortar were imporant.

关键词： high Relation between Modulus of Elasticity and Compressive Strength of Ultrahigh-Strength Mortar with Mixed Silicon Carbide as Fine Aggregate SIC

CarbonisotopiccompositionandfluxofparticulateorganicmatterintheChangjingRiver

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Acta Oceanologica Sinica 1998年第3期17卷 337-342页

作者： Cai Deling Han Yibing(Received June 5, 1996 acceptedJuly 13, 1997) First Institute of Oceanography State Oceanic Administration Qingdao 266003 China

Particulate organic carbon (POC) and its isotopic composition were measured monthly in the ChangjiangRiver (at Sta. Datong)for a whole year. It shows that their seasonal distribution has an obvious change and is similarto that of the Huanghe River. The annual weighted mean of POC 13 C values of the Changjiang River is almost the same as that of the Huanghe River. Based on the data of runoff and sediment load measured daily and POC concentra-tion measured monthly the POC flux at Sta. Datong was estimated. The flux value at Datong may be considered ap-proximately to be the M flux of the Changjiang River discharging into the sea. The M flux of the Changjiang Riv-er is slightly larger than that of the Huanghe River.

关键词： POC flux inputing to seas Changjiang River carbon isotopes

A New Ceramide from the Soft Coral Cladiella humesi Verseveldt

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Chinese Chemical Letters 2000年第9期11卷 783-784页

作者： Ming Yan WANG Yi LUO Jing Yu SU Department of Chemistry, Zhongshan University, Guangzhou 5 10275 Zhongshan Univ Dept Chem Guangzhou 510275 Peoples R China

A new ceramide, humesamide, was isolated from the soft coral Cladiella humesi Verseveldt, which was collected from Linshui County of Hainan Province. Its structure was established by spectroscopic analysis and chemica... 详细信息

关键词： Cladiella humesi soft coral ceramide sphingosine

激光增材制造DZ40M的微观组织及热处理研究

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中国激光 2018年第10期45卷 111-118页

作者：孟翔田象军程序汤海波北京航空航天大学大型金属构件增材制造国家工程实验室北京100191 北京航空航天大学材料科学与工程学院北京100191 国防科技工业激光增材制造技术研究应用中心北京100191 大型整体金属构件激光直接制造教育部工程研究中心北京100191 大型关键金属构件激光直接制造北京市工程技术研究中心北京100191

采用激光增材制造技术制备了钴基高温合金DZ40M,研究了沉积态DZ40M的微观组织,对比分析了不同热处理制度下DZ40M的微观组织及力学性能。结果表明,激光增材制造技术得到的DZ40M组织比传统定向凝固的更细,拉伸强度及塑性都有不同程度的增... 详细信息

采用激光增材制造技术制备了钴基高温合金DZ40M,研究了沉积态DZ40M的微观组织,对比分析了不同热处理制度下DZ40M的微观组织及力学性能。结果表明,激光增材制造技术得到的DZ40M组织比传统定向凝固的更细,拉伸强度及塑性都有不同程度的增大。1280℃固溶处理能够使DZ40M的初生碳化物充分固溶并析出新的共晶组织,再经950℃或者1020℃的时效处理,有二次碳化物析出,时效处理对DZ40M力学性能起到良好的强化作用,并在一定范围内保留其塑性,其中1280℃/4 h+1020℃/12 h热处理制度处理试样,能够在提高室温抗拉强度的同时,最大程度地保留沉积态塑性。

关键词：激光技术激光增材制造钴基高温合金微观组织静拉伸力学性能热处理

Application of Tungsten as a De-NO_x Catalyst

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Rare Metals 1994年第3期13卷 229-235页

作者： Nakatsuji T.(Sakai Chemical Industry, Co. , LId. 5-I, Ebisujimacho Sakai Osako 590, Japan) Sakai Chemical Industry Co 日本

Abstract A catalyst for removal of nitrogen oxides, in stationary Sources, requires many kinds of characteristicsfor commercial application. At first, a vanadium pentaoxide based catalyst was used for the NO-NH3-OZreaction because of its high activity at lower temperatures. But it was`later found that this catalyst had *** like a low thermal durability and a high conversion rate of SO: to SO3. On the other hand, tungstentrioxide was well known as a catalyst that has a high thermal durability and a low conversion rate of SOZto SO3 but showed a low activity at appropriate temperature. For these reasons, tungsten trioxide basedcatalysts have not been used in the reaction in most actual plants except for special cases. Further *** on this catalyst revealed that a catalyst comprising of titania f80 wt%￣ 90 wt%j- tungsten trioxide(5 wt% ￣ 15 wt%j, and vanadium pentaoxide (0,l wt%￣ 5 wt%j, showed a high thermal durability and alow conversion rate of SOZ to SO3 as well as high activity towards the NO-NHrOz reaction.

关键词： NO De

Numerical study of pollutant transport in the sea-bay with mild slope beach

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Acta Oceanologica Sinica 1998年第3期17卷 399-408页

作者： Wang Zeliang and Tao Jianhua(Received December 22, 1996 accepted January 5, 1997) Department of Mechanics Tianjin University Tianjin 300072 China

Using the slot method, the moving boundary problem caused by the change of the tide water elevation is treated. A two-dimensional advection - diffusion model with moving boundary is proposed, and the input pollutant is considered as moving source to meet the water level variation. The model given in this paper has been used to simulate the pollutant transport in the Bohai Gulf, the computational results are in good agreement with the measured data.

关键词： Slot method advection-diffusion mild slope beach moving source

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science China Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5, SUN Junying4,5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate Center, China Meteorological Administration, Beijing 100081, China 2. Climate Change Institute, University of Maine, Orono, ME 04469, USA 3. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 4. Chinese Academy of Meteorological Sciences, Beijing 100081, China.5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change Institute University of Maine 04469 Orono ME USA 3. Institute of Tibetan Plateau Research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. Chinese Academy of Meteorological Sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Modelling of the Relaxation Least Squares-Based Neural Networks and Its Application

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Journal of Systems Engineering and Electronics 2002年第2期13卷 16-21页

作者： Lu Kongkuo, Chen Zengqiang & Yuan ZhuzhiDepartment of Automation, Nankai University, Tianjin 300071, P.R.China(Received July 5, 2001) Department of Automation Nankai University Tianjin 300071 P.R. China

A relaxation least squares-based learning algorithm for neual networks is proposed. Not only does it have a fast convergence rate, but it involves less computation quantity. Therefore, it is suitable to deal with the case when a network has a large scale but the number of training data is very limited. It has been used in converting furnace process modelling, and impressive result has been obtained.

关键词： Backpropagation Learning systems Least squares approximations

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新编股份制企业会计与财务.税收

Primal　Dual　Algorithms　for　the　Lexicographically　Optimal　Base　of　a　Submodular　Polyhedron　and　Its　Relation　to　a　Poset　Greedoid

作者：戴克让等7-200-02480-5

来源：南通市图书馆图书评论

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Systems Science and Systems Engineering 1995年第3期5卷 193-203页

作者： Kakuzo Iwamura(Sanbcho-Heights 901 Sanbancho 1-5 Utsunomiya 320,Japan)

We show that for a submodular polyhedron and its dual supermodular polyhedron the exists a unique lexicographically optimal base with respect to a weight vector and they *** also present a dual algorithm to get the lexicograpllically optima base of a submodular polyhedron which works on its dula superlnodular *** dual algorithm completely agrees to the algorithm of Morton,*** von Tandow,*** Ringwald,K.[1985],where their underlying distributive lattice is a chaill poset *** we show that finding the lesicographically optimal base of a submodular system is essentially equivalent to finding the lexicographically optimal base of a simple submodular system,where its underlying distributive lattice is a poset *** *** the importance of greedoids in a further development of submodular system theory.

关键词： Lexicographically optimal Base poset greedoid,weight vector