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Liquid drying of BeO gelcast green bodies using ethanol as liquid desiccant
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作者 王小锋 彭超群 +2 位作者 王日初 孙月花 陈以心 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2466-2472,共7页
BeO gelcast green bodies were dried by liquid drying method with liquid desiccant ethanol.Effects of ethanol concentration,solids loading and aspect ratio of green body on the moisture and shrinkage of green bodies we... BeO gelcast green bodies were dried by liquid drying method with liquid desiccant ethanol.Effects of ethanol concentration,solids loading and aspect ratio of green body on the moisture and shrinkage of green bodies were studied through measuring mass and dimension.Additionally,liquid drying stress was analyzed and a model of the initial stage drying stress was established.The results show that higher ethanol concentration,lower solids loading and higher aspect ratio of gelcast green bodies increase the drying rate.Increasing the ethanol concentration decreases the shrinkage rate.Liquid drying stress is generated due to a non-uniform drying rate.During the process of liquid drying,the inner drying stress of the green body changes from compressive stress to tensile stress,while the outer drying stress changes from tensile stress to compressive stress. 展开更多
关键词 BEO GELCASTING green body liquid desiccant ETHANOL drying rate shrinkage rate drying stress
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Green coffee bean extract improves obesity by decreasing body fat in high-fat diet-induced obese mice 被引量:3
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作者 Bong-Keun Choi Sung-Bum Park +4 位作者 Dong-Ryung Lee Hae Jin Lee Ying-Yu Jin Seung Hwan Yang Joo-Won Suh 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第7期616-624,共9页
Objective:To evaluate possible lipid catabolism and body fat regulation effects of 3-caffeoylquinic acid in Green coffee bean extract(GCBE) in high-fat diet(HFD)-induced obese mice.Methods:Obesity was induced in mice ... Objective:To evaluate possible lipid catabolism and body fat regulation effects of 3-caffeoylquinic acid in Green coffee bean extract(GCBE) in high-fat diet(HFD)-induced obese mice.Methods:Obesity was induced in mice using a HFD for four weeks.Then,mice were fed only HFD or HFD with GCBE at 50,100,and 200 mg/kg.Fatty acid synthesis mechanism regulation of body fat was investigated through real-time PCR and Western blot assay.Body fat reduction was measured through dual-energy X-ray absorptiometry.Results:In HFD-induced obese mice,GCBE treatment significantly decreased body weight gain,liver weight and white adipose tissue weights with regulation of adipose tissue lipolysis hormones,like adiponectin and leptin.GCBE treatment decreased mR NA expression levels of adipogenesis and adipocyte metabolism related genes in adipose tissues and the liver,and decreased the corresponding protein expression.Dual energy X-ray absorptiometry measurements were used to compare body fat between mice on high-fat and those treated with GCBE.GCBE treated mice had a lower fat mass compared to HFD alone fed mice and relative body weight and fat mass were markedly decreased.Conclusions:GCBE has a potential anti-obesity effect with lowering body fat accumulation by regulating adipogenesis and lipid metabolism-related genes and proteins in WAT and liver. 展开更多
关键词 green coffee BEAN EXTRACT High-fat diet INDUCED OBESE MICE Adipogenesis body fat Dual energy X-ray ABSORPTIOMETRY
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Side Wall Effects on the Hydrodynamics of a Floating Body by ImageGreen Function Based on TEBEM 被引量:3
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作者 Jikang Chen Lijia Wang Wenyang Duan 《Journal of Marine Science and Application》 CSCD 2018年第3期353-361,共9页
A novel numerical model based on the image Green function and first-order Taylor expansion boundary element method(TEBEM), which can improve the accuracy of the hydrodynamic simulation for the non-smooth body, was dev... A novel numerical model based on the image Green function and first-order Taylor expansion boundary element method(TEBEM), which can improve the accuracy of the hydrodynamic simulation for the non-smooth body, was developed to calculate the side wall effects on first-order motion responses and second-order drift loads upon offshore structures in the wave tank. This model was confirmed by comparing it to the results from experiments on hydrodynamic coefficients, namely the first-order motion response and second-order drift load upon a hemisphere, prolate spheroid, and box-shaped barge in the wave tank. Then,the hydrodynamics of the KVLCC2 model were also calculated in two wave tanks with different widths. It was concluded that this model can predict the hydrodynamics for offshore structures effectively, and the side wall has a significant impact on the firstorder quantities and second-order drift loads, which satisfied the resonant rule. 展开更多
关键词 Taylor expansion boundary element method Side wall effects Image green function HYDRODYNAMICS Sharp corner floating body
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From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials 被引量:1
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作者 Shaojun LIU(Department of physics, Beijing Normal University, Beijing 100875, China)Xiaobo WEI(Department of Physics, Liuzhou College of Education, Liuzhou 545005, China)Zhaodou CHEN Jun CAI and Benkun MA(Department of Physics, Beijing Normal University, 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第4期315-319,共5页
In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hoppin... In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method. 展开更多
关键词 Rev Li CHEN From the green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body
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Effects of agarose concentration and addition on the properties of gel-cast 3Y-ZrO2 green and sintered bodies
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作者 王璀璨 陈常连 +2 位作者 huang xiao-yu luo ma-ya huang zhi-liang 《Journal of Chongqing University》 CAS 2016年第2期61-71,共11页
Using agarose as a gel agent to prepare ceramics is a suitable non-toxic gel-casting method. The effects of agarose concentration and addition amount on gel-cast 3Y-ZrO2 green and sintered bodies were investigated. Gr... Using agarose as a gel agent to prepare ceramics is a suitable non-toxic gel-casting method. The effects of agarose concentration and addition amount on gel-cast 3Y-ZrO2 green and sintered bodies were investigated. Green bodies were prepared by gel-casting using an agarose solution of a different agarose mass fraction including 3.0%, 3.5%, 4.0%, 4.5%, 5.0% and 5.5% with an added amount of agarose in the green body at a mass fraction of 0.7%, and using the agarose solution of a mass fraction of 4.5% with a different amount of added agarose including 0.6%, 0.7%, 0.8%, 0.9%, and 1.0% in terms of mass fraction. The green bodies were sintered at I 600 ~C for 4 h. The relative density, linear shrinkage, and bending strength of the green bodies, and L^e density, microstructure, bending strength, and fracture toughness of sintered samples were characterized and analyzed. Results show that comprehensive properties of green bodies made with 4.5% (in terms of mass fraction) agarose solution added to an mass fraction of agarose in the slurry at 0.6% were the best, of which the bending strength was 3.14 MPa, the linear shrinkage was below 4.3%, and the relative density is 57.3%. For sintered bodies, the best fracture toughness was 5.63 MPa m1/2, and the optimal density was 5.88 gcm-3. 展开更多
关键词 GEL-CASTING 3Y-Zr02 AGAROSE green body sintered body
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Joining of ZrO_2/CePO_4 Green Bodies Using Slurries
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作者 刘名郑 刘家臣 +3 位作者 高海 王丽娟 霍伟荣 王凯利 《Transactions of Tianjin University》 EI CAS 2004年第2期130-132,共3页
Ce-ZrO2 and ZrO2/CePO4 ceramic system was joined in the green body by using mixed powder. Three kinds of systems are discussed. The microstructure and bending strengths of the joint were investigated and it is found t... Ce-ZrO2 and ZrO2/CePO4 ceramic system was joined in the green body by using mixed powder. Three kinds of systems are discussed. The microstructure and bending strengths of the joint were investigated and it is found that the Ce-ZrO2 and 30%CePO4/ZrO2 ceramics can be well joined in the green body. A joint with high mechanical property and good microstructure can be obtained after sintering without applied pressure. Complexly shaped ceramic components can be created by the technique of green state joining. A new way to produce them is provided and the cost is reduced due to the simplicity of the process. 展开更多
关键词 green body joining different advanced ceramics SLURRY
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Body Size as an Indicator of Health for Green Turtles at the TCMP (Tobago Cays Marine Park), Eastern Caribbean
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作者 Olando Keri Harvey 《Journal of Environmental Science and Engineering(A)》 2013年第5期306-310,共5页
Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because t... Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because their globally endangered status have become the focus of an in-water monitoring program, primarily for green turtles (Chelonia mydas). Preliminary assessment indicated that the TCMP contains an important foraging aggregation of sub-adult green turtles. Since then two additional years of data has been collected; this data was analyzed to assess the health of the turtle population. The data also indicated that the weight was predictable according to carapace width and length and that the population is dominated by larger sub-adults. 展开更多
关键词 green turtles marine protected area health indicator body size.
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Numerical Investigation of Heave and Pitch Motion Effects on Green Water Loading for a Floating Body 被引量:1
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作者 K.Ravindra Babu R.Datta A.Bhattacharyya 《Journal of Marine Science and Application》 CSCD 2019年第4期457-471,共15页
In this paper,the influence of heave and pitch motions on green water impact on the deck is numerically investigated.The vessel motions are determined using a potential theory based method and provided as input to fin... In this paper,the influence of heave and pitch motions on green water impact on the deck is numerically investigated.The vessel motions are determined using a potential theory based method and provided as input to finite volume based CFD computations of green water phenomenon.A dynamic mesh approach is adopted to determine instantaneous body positioning in the fluid domain.Detailed validation studies with published experimental results for 2D and 3D fixed vessel cases are initially performed to validate the present numerical approach before studying the moving vessel problem.The results show that inclusion of heave and pitch motion changes the disturbed wave field near the bow which influences the free surface as well as the impact loading due to green water.The effect of wave steepness on green water impact is also investigated and it is seen that the present numerical method is capable of capturing green water load.It is observed that the effects of vessel motions on green water load are not negligible and one should consider this effect too.The incorporation of vessel motions in the vertical plane affects the green water loading on the deck. 展开更多
关键词 greenwaterimpact pressure Relativewaveheight Vertical bowmotion Heaveand pitchmotions Wave steepness Floating body
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Volatile Flavor Components and the Body Weights of Rats in the Green Tea Added Miner Ingredients
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作者 Sung-Hee Choi Hye-Jin Hwang 《茶叶》 2013年第4期321-324,共4页
In order to change for the good flavor in green tea of middle or low grade,roast naked barley(miner ingredient) was added to it.To make tea having functional property,mixed roast naked barley-green tea with one medici... In order to change for the good flavor in green tea of middle or low grade,roast naked barley(miner ingredient) was added to it.To make tea having functional property,mixed roast naked barley-green tea with one medicinal herb(MH,miner ingredient).This study was performed to investigate the effect of drinking extracts of naked barley- MH- green tea(A group) and adlay- Angelica gigas Nakai- green tea(B group) on the body weights of rats,and volatile flavor components of best effective extract on weight reduction.Forty-eight male Sprague-Dawley rats divided into six groups were fed five different green tea extracts for 8 weeks.The result obtained in the experiment indicated that the change of body weights of rats was affected by A group,B group and others.A group showed highest reduction rate of body weights(36.40%).Reduction rate of body weights on the B group(10.10%) was much lower than A group(36.40%).Aroma compounds were extracted by the SDE method.The concentrated aroma extracts were analyzed and identified by GC and GC-MS.The main aroma components of the green tea blended with naked barley and MH were 12 pyrazines having roasty note,methyl butanals having sweet note,hexanal having briskness greenish note,and nerolidol and β-ionone having floral note. 展开更多
关键词 绿茶提取物 挥发性成分 SPRAGUE-DAWLEY 体重 大鼠 矿工 GC-MS分析 挥发性香味成分
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平面星体的一类Green-Osher不等式
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作者 袁名扬 张德燕 《延边大学学报(自然科学版)》 CAS 2024年第1期87-91,共5页
基于文献[4]的研究,利用平面星体和对偶混合体积的性质证明了平面星体的一类Green-Osher不等式,并得到了该不等式等号成立的充要条件是两平面星体位似。
关键词 平面星体 严格凸函数 green-Osher不等式 位似
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单原子Pt负载在锐钛矿(001)表面的电光学特性研究
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作者 靳帆 赵志超 《原子与分子物理学报》 CAS 北大核心 2025年第6期43-50,共8页
基于第一性原理的多体格林函数理论方法,系统探究了锐钛矿TiO_(2)(001)表面负载Pt单原子催化剂的电子结构和光学性质,考虑Pt在完美表面和缺陷表面(O空位)两种基底上的负载.结果发现,Pt会在TiO_(2)禁带中间、价带和导带边缘引入新能级,... 基于第一性原理的多体格林函数理论方法,系统探究了锐钛矿TiO_(2)(001)表面负载Pt单原子催化剂的电子结构和光学性质,考虑Pt在完美表面和缺陷表面(O空位)两种基底上的负载.结果发现,Pt会在TiO_(2)禁带中间、价带和导带边缘引入新能级,但不同基底负载的Pt单原子催化剂存在不同的带隙特性.Pt的负载会引起体系光学吸收红移,增大光学吸收范围,延伸光吸收至可见光甚至是红外区域,提升可见光活化的可能性,同时改善体系的激子束缚能,有利于空穴与电子有效分离,这可能是Pt负载后光催化性能提升的原因之一.然而,若在可见光或低能量紫外光激发后,分离的电子与空穴没有及时参与反应,体系衰变回最低激发态,此时极大的激子束缚能可能会加速电子与空穴重组,不利于表面催化反应的进行.负载在O空位的催化剂最低激发态的激子束缚能比完美表面小,重组速率慢.计算结果能够为理解单原子催化剂结构-性能关系提供一些见解. 展开更多
关键词 二氧化钛 Pt单原子催化剂 多体格林函数理论 电子结构 光吸收
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体心立方Ising模型的Green函数方法处理
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作者 滕保华 《成都科技大学学报》 EI CAS CSCD 1994年第5期83-87,共5页
本文利用Green函数技术,严格处理了体心立方Ising模型的Hamilton量,得到了可以递推的自旋综合平均值的代数方程。根据该方程,并利用前文的递推原则和切断近似,可以得到体心立方Ising模型的转变温度、自发磁... 本文利用Green函数技术,严格处理了体心立方Ising模型的Hamilton量,得到了可以递推的自旋综合平均值的代数方程。根据该方程,并利用前文的递推原则和切断近似,可以得到体心立方Ising模型的转变温度、自发磁化等。 展开更多
关键词 格林函数 递推原则 体心立方晶格 伊辛模型
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自由表面波Green函数及其导数的快速算法 被引量:5
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作者 周庆标 张纲 朱林生 《计算物理》 CSCD 北大核心 1999年第2期113-120,共8页
快速而又精确地求得领域Gren函数值是应用频域Green函数求解波物相互作用问题的关键。探讨了无限水深频域自由面Green函数及其导数的快速算法问题,提供了一个实用有效的计算方法。
关键词 自由面 边界元 green函数 表面波 快速算法
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Re-fluidising the aged gel for high-density alumina green body 被引量:2
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作者 Xiaolang WU Jin ZHAO +3 位作者 Shunzo SHIMAI Xiaojian MAO Jian ZHANG Shiwei WANG 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第9期1375-1382,共8页
A green body with a density as high as possible is critical to diminish the crisis of deformation or cracking when large-size parts are sintered.Here,a new method,i.e.,re-fluidising the aged ceramic gel is developed t... A green body with a density as high as possible is critical to diminish the crisis of deformation or cracking when large-size parts are sintered.Here,a new method,i.e.,re-fluidising the aged ceramic gel is developed to prepare the high-density green body.Alumina slurry with 56 vol%solid loading and copolymers of isobutylene and maleic anhydride were aged without vaporisation and re-fluidised by non-intrusive shearing after removing the exuded water.The re-fluidised slurry was re-casted.The resultant wet gel was dried and deboned at a low temperature.The relative density of the obtained green body was 64.6%,1.5%higher than that without aging and re-fluidising.The linear sintering shrinkage of the body decreased by 0.7%.The enhanced green density is explained from the viewpoint of the solid loading and the structure of the slurry. 展开更多
关键词 high density green body re-fluidising ALUMINA colloid formation
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Effects of Adhesive Composition on Green Joining of CePO_4-ZrO_2 Ceramics
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作者 田勃然 刘家臣 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第1期17-20,共4页
Green bodies of 25%CePO 4/ZrO 2 and ZrO 2 ceramics were joined at 1450℃ for 120 min without applied pressure by using mix ed powders slurries composed of CePO 4 and ZrO 2. The effects of CePO 4/(CePO 4+ZrO ... Green bodies of 25%CePO 4/ZrO 2 and ZrO 2 ceramics were joined at 1450℃ for 120 min without applied pressure by using mix ed powders slurries composed of CePO 4 and ZrO 2. The effects of CePO 4/(CePO 4+ZrO 2) ratio of the adhesive on the bond strength of the joints were invest igated. Maximum bond strength of 414MPa was obtained by joining an adhesive wit h the ratio of 0.5. Under the experimental conditions, the grain size of the par ticles grown in the joint was smaller than that in joined ceramics. The microstr ucture of the joint was more homogeneous than that of the matrix and without obv ious cracks, pores and other defects. 展开更多
关键词 green body SLURRIES joint interface
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Green State Joining ZrO_2/Al_2O_3 Ceramics by Metal Interlayer
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作者 张君娣 刘家臣 +1 位作者 叶浩 门荣磊 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期194-196,共3页
Green bodies of Al_2O_3 and ZrO_2 ceramics were joined without applying pressure by using metal slurries of Al as an interlayer according to the mechanism of volume expansion in the oxidation process of Al+O_2→Al_2O_... Green bodies of Al_2O_3 and ZrO_2 ceramics were joined without applying pressure by using metal slurries of Al as an interlayer according to the mechanism of volume expansion in the oxidation process of Al+O_2→Al_2O_3. The microstructure of the joints was investigated. The results shows that interface cracks are easily produced. With addition of Al_2O_3 and ZrO_2 into the interlayer composition, fine joints could be obtained without obvious cracks, pores and other defects. Under the experimental conditions, the grain size of the particles grown in the joint is smaller than that in the parent material. Therefore, the addition of Al_2O_3 or ZrO_2 can buffer the defect resulting from the volume expansion in the oxidation process. And in the existence of Al_2O_3 or ZrO_2 in the interlayer, active Al_2O_3 can boost the interface reaction. 展开更多
关键词 joining INTERFACE SLURRY green body
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Some Methods of Solution of Problems of Sound Diffraction on Bodies of Non-Analytical Form
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作者 A. A. Kleshchev 《Open Journal of Acoustics》 2016年第4期45-70,共27页
This review analyzes following numerical methods of a solution of problems of a sound diffraction on ideal and elastic scatterers of a non-analytical form: a method of integral equations, a method of Green’s function... This review analyzes following numerical methods of a solution of problems of a sound diffraction on ideal and elastic scatterers of a non-analytical form: a method of integral equations, a method of Green’s functions, a method of finite elements, a boundary elements method, a method of Kupradze, a T-matrix method and a method of a geometrical theory of a diffraction. 展开更多
关键词 DIFFRACTION green’s Function Non-Analytical Form Boundary Conditions Elastic body Integral Equation
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A non-perturbation approach in temperature Green function theory
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作者 ZuoWei WangShun-Jin 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第1期14-17,共4页
AnonperturbationapproachintemperatureGrenfunctiontheoryZuoWei(InstituteofModernPhysics,theChineseAcademyofSc... AnonperturbationapproachintemperatureGrenfunctiontheoryZuoWei(InstituteofModernPhysics,theChineseAcademyofSciences,Lanzhou7... 展开更多
关键词 多体作用系统 温度格林函数理论 非微扰方法
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Dynamic response in two-dimensional transversely isotropic thick plate with spatially varying heat sources and body forces
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作者 M.ISLAM S.H.MALLIK M.KANORIA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第10期1315-1332,共18页
This paper deals with a two-dimensional (2D) problem for a transverselyisotropic thick plate having heat sources and body forces. The upper surface of the plate is stress free with the prescribed surface temperature... This paper deals with a two-dimensional (2D) problem for a transverselyisotropic thick plate having heat sources and body forces. The upper surface of the plate is stress free with the prescribed surface temperature, while the lower surface of the plate rests on a rigid foundation and is thermally insulated. The study is carried out in the context of the generalized thermoelasticity proposed by Green and Naghdi. The governing equations for displacement and temperature fields are obtained in the Laplace-Fourier transform domain by applying the Laplace and Fourier transforms. The inversion of the double transform is done numerically. Numerical inversion of the Laplace transform is done based on the Fourier series expansion. Numerical computations are carried out for magnesium (Mg), and the results are presented graphically. The results for an isotropic material (Cu) are obtained numerically and presented graphically to be compared with those of a transversely isotropic material (Mg). The effect of the body forces is also studied. 展开更多
关键词 generalized thermoelasticity green-Naghdi model transversely isotropic material spatially varying heat source body force
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等静压陶瓷生坯镗孔加工技术研究
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作者 范玉龙 徐万里 +1 位作者 王晓东 王蒙蒙 《机械》 2024年第11期16-22,共7页
陶瓷生坯加工技术由于具有加工效率高、加工费用低、刀具磨损小而被广泛应用于复杂陶瓷零件制备成型中,但是刀具的使用寿命、瓷坯的表面质量等都是等静压复杂瓷坯加工中面临的关键挑战。本文首先通过刀具优化,确定了适宜等静压坯体加工... 陶瓷生坯加工技术由于具有加工效率高、加工费用低、刀具磨损小而被广泛应用于复杂陶瓷零件制备成型中,但是刀具的使用寿命、瓷坯的表面质量等都是等静压复杂瓷坯加工中面临的关键挑战。本文首先通过刀具优化,确定了适宜等静压坯体加工的镶嵌金刚石刀具,研究发现镶嵌金刚石刀片具有很好的耐磨损性能,单片加工瓷坯的数量较硬质合金刀具提高了200%,且坯体表面光洁度得到了明显改善,解决了等静压坯体加工表面质量差的问题。其次,通过改进钻孔工艺,即将钻头钻孔改为内圆镗孔刀镗孔操作,不仅大大降低了刀具因加工过程产生的过热现象,提高了刀具切削效率,而且显著降低内外圆加工余量,提高生产效率。 展开更多
关键词 等静压 陶瓷生坯 加工刀具 内圆镗孔
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