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Experimental Study of Energy-Saving Air-Conditioner with Hot Water

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湖南大学学报（自然科学版） 2009年第S1期36卷 75-78页

作者： CHEN Jian-bo,CHEN Dan,LU Ying(university of shanghai for science and {3.,shanghai,China) university of shanghai for science and {3. Shanghai 200000 China

Energy-saving air-conditioner with hot water is an air source heat pump air-conditioner,which can also supply hot *** hot water is heated by a double pipe condenser connected with an air-cooled condenser in series in the *** experiment of the energy-saving air-conditioner was carried out in the enthalpy-difference air-conditioner *** hot water temperature and the compressor's discharge and suction pressure were recorded in the working condition,where the ambient temperature was at 43.℃,3. ℃,21 ℃,7 ℃,and 2 ℃ *** results showed that the system operated stably and *** system can supply 240 L hot water at 50 ℃ in the whole year,and its coefficience of performance(COP)is much higher than the conventional air source heat pump *** energy conservation was proved by comparing the thermal efficiency with other sourece water heaters.

关键词： air-conditioning water heaters energy conservation heat pump systems thermal efficiency

Equilibrium Precipitation of Niobium Carbonitride in Austenite

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 119-122页

作者： Fuming Wang Wenchao Li(Applied science school, university of science and technology Beijing, Beijing 100083. China) Applied science school University of Science and Technology Beijing Beijing 100083 China

The equilibrium between niobium carbonitride and austenite has been studied. Experimentally, X-raydiffaction technique was adopted to verify that the precipitates have the same composition and structure. Theoretical-ly, Hillert and Staffansson's regular model about stoichimetric phase was used to describe the thermodynamic proper-ties of multi-component precipitate. Calculated results agree well with experimental values from literatures.

关键词： equilibrium niobium precipitate, austenite

Microstructural Features During Strain Induced Ferrite Transformation in 08 and 20Mn Steels

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Journal of university of science and technology Beijing 2001年第2期8卷 105-110页

作者： Ping Yang, Feng-e Cui, Fuming Wang (Materials science and Engineering school, university of science and technology Beijing, Beijing 100083. China) (Metallurgy school, university of science and technology Beijing, Beijing 100083. China) Univ Sci & Technol Beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China

The microstructure evolution during strain induced ferrite transformation was followed in thermal-simulation tests of clean 08 and 20Mn steels. The influences of carbon equivalence and initial austenite grain size on ferrite grain refinement and the volume fraction of ferrite during straining were inspected. The results revealed that the accelerating effect of ferrite transformation by strain was increased as the carbon equivalence decreased. However, finer ferrite grains were obtained at higher carbon content. At strain of similar to1.5 ferrite grains less than 3.mum and 2 mum can be obtained in 08 and 20Mn steels respectively. Whereas the ferrite grain refinement in 08 steel was due to both effects of strain induced transformation and ferrite dynamic recrystallization, that in 20Mn was mainly due to strain induced transformation. Heavy strain can produce fine ferrite grains in coarse austenite grained 08 steel, but it would lead to band microstructure in coarse austenite grained 20Mn.

关键词： clean carbon steel strain induced transformation grain refinement ferrite dynamic recrystallization

Impact chaos control and stress release——A key for development of ultra fine vibration milling

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Progress in Natural science:Materials International 2002年第5期12卷 18-23页

作者： WANG Shulin(Department of Power Engineering, university of shanghai for science and {3., shanghai 200093. China) shanghai Univ Sci & Technol Dept Power Engn Shanghai 200093 Peoples R China

Through our previous experimental and analytical studies, it has been discovered that the key for the development of vibration milling is the impact chaos control and stress release. The necessities for the chaos control and stress release are: (i) to strictly e-liminate the sub-harmonics; (ii) to control the super-harmonics to a lower level and (iii) to load the system compressively with relatively higher period, in order that the vibration energy can be absorbed by the particles effectively and sufficiently. A new vibration model for ultra fine milling is proposed, which has wide applications in preparing ultra fine particles.

关键词： vibration mills ultra fine milling impact chaos control stress release.

Calculating model of mass action concentrations for Ag-Au-Cu melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG Jian Metallurgy school, university of science and {3. Beijing, Beijing 100083. China Metallurgy school University of Science and Technology Beijing 北京 100083

Based on phase diagrams and measured activities, the calculatingmodel of mass action concentrations for het- erogeneous meltsAg-Au-Cu was formulated. Calculated results agree with the improvedresults of recent research work, Showing that the model formulatedcan reflect the structural characteristics of these melts. In thismodel, without the help Of any empirical parameters, only threeequilibrium constants are used, hence it is simple, lear, andfavorable to the sim- Plification of calculation.

关键词： activity mass action concentration eutectic Solid solution

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science China(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3. FENG ChengMing1 1 Mechanical and Electronic Engineering College, Shandong Agricultural university, Tai’an 271018, China 2 College of Materials science and Engineering, university of science and technology, Beijing 100083. China 3.College of Material science and Engineering, Beijing university of Chemical technology, Beijing 100029, China Mechanical Electronic Engineering College Shandong Agricultural University Tai’an 271018 China College of Materials science Engineering University of Science technology Beijing 100083 China College of Material science Engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical Engineering school.university of science and {3. Beijing, Beijing 100083. China Metallurgical Engineering school University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

Manufacture of the Ultrafine Grain WC/Co Cemented Carbides by Combined Sintering Processing

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 208-213页

作者： Binghai Liu Yue Zhang Shixi Ouyang Qikai Li(Institute of Technical Physics and Chemistry, east China university of science and {3. , shanghai 20023., China)(Material science and Engineering school. university of science and {3. Beijing, Beijing 100083. China)(State Key Laboratory for Synthesis and Processing of Advanced Materials. Wuhan university of science and {3., Wuhan 43.070, China,) E China Univ Sci & Technol Inst Tech Phys & Chem Shanghai 200237 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Wuhan Univ Sci & Technol State Key Lab Synth & Proc Adv Mat Wuhan 430070 Peoples R China

A new kind of sintering process, combined sintering process. i.e. vacuum sintering plus hot isolate pressure sintering (HIP), was introduced for producing ultrafine WC-10% Co (mass fraction. so as the follows) cemented carbides. The effects of some processing parameters on the microstructure and mechanical properties of the obtained cemented carbides were studied. The results show that the rapid shrinkage and the pronounced densification of tile cemented carbides took place during the vacuum sintering stage, which is intinaately correlated with the local liquid sintering occurred during this earl} sintering stage for the high surface activity of ultrafine WC-Co powder. The way of high pressure imposing. isothermal treatment cycle during *** sintering and HIP sintering stage directly influence the densitication of compacts and the mechanical properties of the produced WC-10%Co cemented carbides.

关键词： ultrafine WC-Co cemented carbides vacuum sintering HIP sintering

Sandwich Magnetoelectric Composites of Polyvinylidene Fluoride,Tb-Dy-Fe Alloy,and Lead Zireonate Titanate

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Journal of Wuhan university of technology(Materials science) 2007年第4期22卷 596-599页

作者：赵广辉熊传溪 State Key Laboratory of Advanced technology for Materials Synthesis and Processing school of Computer science and technology Wuhan University of TechnologyWuhan 430070China school of Materials science and Engineering Wuhan University of TechnologyWuhan 430070China

The novel sandwich composites were prepared by sandwiching a polyvinylidene fluoride/Tb- Dy-Fe alloy composite （PVDF/Terfenol-D） between polyvinylidene fluoride/lead zirconate titanate composites （PVDF/PZT）. The maximum magnetoelectric effect voltage coefficient, （dE/dn）3.max, of the sandwich composites is higher than that of three-phase composites at their own optimal loading level of Terfenol-D. This is attributed to less interface relaxations of strain and better polarization of the sandwich composites. When the volume fraction of Terfenol-D is higher than 0.10, no coupling interaction for three-phase composites could be observed, but （dE/dn）3.max of sandwiched composites still reached 20 mV/（***）. At high magnetic field intensity, the magnetoelectric effect voltage coefficient, （dE/dn）3., of sandwich composites is higher than that of three-phase composites; at low magnetic field intensity, （dE/dn）3. of sandwich composites is lower than that of three-phase composites. At their resonance frequency, the （dE/dn）3.max of the sandwich composites and the three phase composites are 150 mV/（***） and 42 mV/（cmoOe）, respectively. This significant increase of （dE/ dn）3.max at resonance frequency confirms the improvement of maximum magnetoelectric effect coefficient via sandwich-structured composites.

关键词： magnetoelectric piezoelectric sandwiched composites