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To improve surface planarity, a translational movement is added into the magnetorheoloigcal planarization process. To explore effects of some process parameters, including trajectory type, stroke and reciprocate velocity, on surface planarity, a set of finishing experiments are carried out. The results show that planarity is well improved when the trough reciprocates perpendicularly to the air gap. Surface planarity decreases as stoke increases but is hardly affected by reciprocate velocity. Using the magnetorheoloigcal planarization process with addition of translational movement, an ultra-smooth surface with planarity of micron order in PV is achieved on a K9 optical glass.

High-efficiency and precision machining of complicated components can be realized by using metal-bonded CBN grinding wheel. However, the difficulty in dressing those superabrasive grinding wheels is one of the main obstructions to popularize its application in industry. Different from the traditional methods, the aim of the paper is to investigate the electro-discharge dressing of bronze-bonded CBN formed grinding wheel. Based on the analysis of electrical discharge parameters and grinding performance, the results show that electro-discharge dressing of CBN formed grinding wheel is feasible. With the increase of pulse duration, pulse voltage and pulse current, the dressing efficiency is increasing, more abrasive grains are protruding, but surface topography of grinding wheel is worsen. Therefore, grinding tests show that, in order to get the dressing quality better and keep the dressing efficiency higher, the bigger electrical discharge parameters are chosen for rough dressing process and the smaller ones are chosen for finishing process.

JI006 block is a key blocks of improve productivity in the JI7 well area. This blocks development of well after fracturing,the fracturing effect are different. To further improve the block after the fracturing effect,should focus on the analysis of influence factors of productivity after fracturing. But have different influence factors and influence degree. In order to analyze the influence of various factors on the Fracturing effect influence degree. This paper uses the grey correlation analysis method to the JI 006 block 15 fracturing Wells formation parameters and fracturing parameters influence after the pressure effect is analyzed,To determine the factors influencing the Fracturing effect. Analysis results is more accurate, the method to choose well layer and the fracturing design and construction has certain guiding significance.

Magnetorheological finishing (MRF) is an advanced machining technology can achieve high efficiency and smoother surfaces. This study discusses the material removal mechanism of MRF, and proposes a kind of magnetorheological fluid with the nano-diamond abrasives. A series of experiments on the BK7 optical glass were conducted to investigate effects of the concentration of nano-diamond abrasives on surface quality and removal efficiency.

Copper-tungsten alloy which is widely used in the field of EDM has high melting temperature and excellent electrical and thermal conductivity. Copper tungsten electrodes for electrical discharge dressing of metal-bond wheel were studied, and experiments were conducted to observe their wear performance in this paper. Orthogonal experiment was designed to explore the wear at the edge of and the bottom of electrode with the machining of holes. Thickness of the carbon layer, micro topography and experimental results were analyzed. Low current and big pulse duration can reduce the electrode wear rate. Although carbon on the electrode surface can be wiped out easily, wear rate of copper-tungsten electrode decreases with the increasing in thickness of the carbon at the initial phase. There are fewer cracks and residue presented on the machined surface by microscope.

This paper considers the multi-resource and multi-point emergency scheduling problem in the hazardous materials logistics accident, and a model of scheduling and the corresponding heuristic algorithm is proposed. Based on the resource classification, the resource that needed by two or more accident points is picked up, by considering the time and cost, a timely and fair scheduling plan is obtained. Finally, a case study is presented to verify the effectiveness of the algorithm.

Magnetic characteristics of three magnetic polishing fluids such as magnetic fluid (MF), magnetorheological fluid (MRF), and magnetic compound fluid (MCF) under magnetic field are experimentally investigated and analyzed. Their magnetic cluster structures under action of magnet field are observed, and their magnetic cluster models are established. Magnetic flied assisted polishing experiments for tungsten carbide are developed used these three kinds of magnetic fluids, material removal and surface roughness are respectively measured. At last, the machining characteristic of three magnetic fluids are contrasted and discussed according to experimental results.

In this paper, a novel area taking MRF process using permanent magnet as excitation was proposed. Four types of permanent magnet configurations were considered. Polishing experiment was conducted. Effects of different permanent magnet configurations on material removal rate (MRR) were discussed.

Energy efficiency and CO2 emission efficiency have been improved from 2005 to2010 in China, but the inter-provincial differences was larger. The provinces have the higher efficiency, which are located in the eastern coastal areas or the southern regions. The provinces have the lower efficiency are located in the central and western inland areas or northern regions. There is a very close relationship between energy use and CO2 emission efficiency in China. Energy saving is the biggest dominant factor of CO2 emission efficiency improvement. Energy conversion plays a efficiency improvement role in some provinces. But industrial structure is the biggest factor hindering the improvement of CO2 emission efficiency. In the future, we should focus on the rational use of energy, regard energy conservation as the dominant factor of carbon emission efficiency improvement, and excavate the enormous potential of the energy conversion factor and expansion the industrial structure factor effect through industrial transformation.

t is challenging to achieve good surface quality and high efficiency simultaneously when machining thin film solar panels. In this study the machining characteristics of a multilayered thin film structure were investigated using diamond wire sawing and grinding. It was found that the efficiency in sawing was significantly greater than that of the employed grinding process, but the machined surface quality was much worse. The results indicated that grinding could still be the solution for such processing and sawing must be improved before this technology could be further progressed for machining thin film multilayered structures.

Cryptotanshinone, tanshinone I, and tanshinone IIA were analyzed by High-performance liquid chromatography /electrospray ionization-mass spectrometry. MSn spectra were obtained and optimized by energy collision induced dissociation (CID) from [M+H]+ ions, the effect of collision energy on production of fragmental ions were studied and optimal signals were achieved. With the collision energy of 35%, tanshinones have optimal signals of fragmental ions and maximal amounts of product fragment ions respectively. The fragmentation pathways for the compounds were studied, and this information would be helpful for the quantitative and pharmacokinetic analysis of tanshinones.

In order to solve the problem of the randomly arrangement of the diamond abrasives, a novel orderly arrangement grinding wheel was developed, which used magnetic field to control the magnetic particles to drive diamond abrasives orderly arrangement. Effects of magnetic flux density on magnetic particle distribution was studied. And effects of magnetic particle proportion on magnetic particle distribution was studied. Grinding experiments were carried out on the tungsten carbide YG8 and surface roughness after grinding was also analyzed.

Routing Optimization is always a key issue in MANET (Mobile Ad-Hoc Network). When referring to multi-media communication, the routing stability, which is up to link stability, is in urgent need. On the analysis of kinds of factors that affect link stability greatly, a multi-dimensional comprehensive evaluation model (MVCLS) was presented based on factor classification. In the model, the weight levels were classified, a mechanism of weight rotation was available, and a normalized link stability evaluation system with multi-attribute and multi-weight was formed. In addition, aiming at reliability and robust of the model, time series analysis and Kalman filter were combined to smooth and predict the value of key factors. At last, the link stability model is used to optimize the OLSR routing protocol, which takes the link stability as the important stuff for path selection. Simulation experiments of modified OLSR were done with support of Qualnet, the results of which show that the network performance is improved and also prove the effectiveness of the link stability model.

The improved maximum power point tracking (MPPT) control based on the reduction of tracking range could reduce the tracking distance of wind turbine effectively, and improve the tracking efficiency. In this study, the relationship between the compensation coefficient of the improved MPPT control and several factors was investigated. Based on simulations of the simplified wind turbine model, wind conditions, air density and wind turbine parameters were used in the studies to investigate the relationship between the optimum compensation coefficients and these corresponding conditions. It can be indicated that in the fact, compensation coefficient is majorly determined by the tracking targets of MPPT and the dynamic performance of wind turbines that determined by the conditions mentioned above. The results also provide guidance for further studies in this area.

This paper studies the damage process induced by dewetting microcracks in composite solid propellant. A nonlinear viscoelastic constitutive model for composite soild propellant is presented. The damage variable D is derived from the microcrack system and is function of microcrack size density. The damage evolution equation is determinded by the extending of microcrack. Form the proposed model of microrack evolution process, an explicit form of damage evolution equation which is a function of stress field is given. The cracking event N and the new crack surface area damage ΔA formed by microcrack extension are defined. Material constants are determinded by acoustic emission tests. The rationality of our model has been confirmed by tension tests.

Galvanic corrosion behavior of 2A12/45 couple under different tensile stresses is investigated using the electrochemical test. Surface morphologies of the specimens are observed by scanning electron microscopy (SEM). The results show that the applied stress have an important effect on the galvanic corrosion of 2A12/45 couple. The couple current density and galvanic corrosion sensitivity increases with the increase of the applied stresses.

Oxygen blowing volume control is very important in Basic Oxygen Furnace (BOF) steelmaking. A combination model based on information theory and artificial intelligence technology is proposed for oxygen blowing volume calculation. The combination model is composed of Case-based Reasoning (CBR) model and Support Vector Machine (SVM) model. In CBR model, the mutual information is introduced in case retrieval step to determine the weights of attributes. In SVM model, the mutual information is adopt to distinguish the importance of input variables by setting a different weight to each variable. The CBR model is viewed as experience based model and the SVM model is viewed as data based model. To model the oxygen blowing volume accurately, CBR model and SVM model are combined. Tests on a 180 ton BOF data are implemented to validate the effectiveness of the proposed method.

The paper mainly introduced research state of coal mine mobile refuge chamber and its outside environmental monitoring system, analyzed particularity of chamber-outside environment and design requirements of outside environmental monitoring system for coal mine mobile refuge chamber, and put forward design goals and idea of software design, hardware design and protective device of outside environmental monitoring system for coal mine mobile refuge chamber. It put forward a design scheme of outside environmental monitoring system for coal mine mobile refuge chamber according to the actual applications and design goals. The design scheme consists of software, hardware and protective device. And it detailed expounded environmental monitoring system’s working principle, signal transmission principle and workflow. The paper can provide technology reference for development of outside environmental monitoring system for coal mine mobile refuge chamber in China.

Optical glass is widely used as the most important material in optical field in recent years. Glass molding press (GMP) has been employed as a promising technique to manufacture optical components in mass production. Heating time and annealing time are the key factors which influence the production cycle. In this paper, an effective method of improving the heating or the annealing effectiveness is to increase the area exposed to the cooling or hot nitrogen by means of adding slots. In the same condition, four models with different slots were built. Based on the theoretical analysis of glass heating and annealing property in the molding process, finite element simulation was carried out. The results showed that the model with slots may decrease the heating and annealing time.

An extracting method of normal residual error from a ground profile was proposed in this paper. Original measurement data was re-processed for obtaining an actual ground profile in an on-machine contact measurement system. The robust Gaussian regression filtering and NURBS fitting methods were employed to filter and fit these discrete data for getting the accurate realistic ground profile. By utilizing iterative partitioning algorithm, the normal residual error could be accurately obtained between the actual ground profile and the ideal one. Measurement data achieved from grinding experiment of aspheric mould were dealt with. After form error compensation grinding, the difference between normal residual error and original reached 40 nm in stead of initially 140 nm.

Silicone oil based magnetic compound fluid was prepared to polishing stainless steel in this paper. The new fluid consists of nano-sized magnetite particle, micro-sized diamonds, micro-sized iron particle and α-cellulose. The characteristics of the fluid were analyzed. The length and quality of the magnetic cluster in the compound fluid was observed under a magnetic field. Polishing experiment of stainless steel was conducted using the silicone oil based magnetic compound fluid on an inclined polishing finishing device. The micro morphology of the stainless steel’s surface was measured. The results showed the surface quality was improved remarkably and the final roughness of the surface was Ra (Average roughness) 0.020μm.

The cementitious system containing FBC ash is usually associated with volume expansion when cured in the normal temperature, due to its relatively high SO3 content. This paper presents a further study on the effect of different curing conditions on the flexural and compressive strength of FBC ash-Portland cement clinker mortar and linear expansion ratio of FBC ash-Portland cement clinker paste. The results show that autoclaved curing is more beneficial to increasing mortar strength in early days than standard curing, but with slow strength development in later period. Moreover, autoclaved curing could decrease the expansion of FBC ash greatly. This study confirms that the expansion of FBC ash can be significantly inhibited by autoclaved curing.

The South–to–North Water Diversion project provides water mainly for Henan and Hebei province , Beijing and Tianjin city . So the ecological environment protection in the water source areas is very important. But the ecological environment of water source areas of the middle route project is damaged becsuse a large amount of fertilizer and pesticide are used in the field, the pollution is heavy, and some lakes are turned into fields at some area. The systematic ecological circulation circles have not been established. This paper puts forward the countermeasures and methods of establishing the ecological circulation circle in the water rource areas of the middle route project after it illustrates the importance of establishing the ecological circulation circle in the water source areas , and analyzes the problems of the ecological circulation circle in the water source areas.

Regional difference of China's CO2 emission is basically in line with the trend of China's economic development that the emission is higher in the eastern coastal areas and lower in the western inland areas. The characteristic of the changes of the total CO2 emission is that the growth rate significantly accelerated after 2000. The basic factor which acts as a drive of CO2 emission increase is economic scale factor and the energy saving factor contributes to the decrease of CO2 emission. The driving power of the population factor and energy conversion factor is weak especially the influence of energy conversion factor is very instable. All the provinces are driven by positive driving force in economic scale factor and most provinces with great driving power are located in the eastern coastal areas. All the provinces are driven by positive driving force without expectation in energy conversion factor and most provinces whose energy saving efficiency improvement is of range small are driven poorly are located in the inland. Provinces are mostly driven positively in population size factor and this is related with size and orientation of driving force and population growth. The reason of the great difference of energy conversion factor is connected with energy consumption scale and change of CO2 emission energy unit consumption.

Glass molding is a high-volume fabrication method for producing optical components. Non-isothermal glass molding press (NGM) was proposed to fabricate optical glass, and its characteristics were studied by finite element method (FEM) simulation. The coupled thermo-mechanical analysis was carried out to analyze the key factors such as temperature distribution, stress distribution and strain distribution. The non-isothermal and isothermal glass molding (IGM) was studied, and optimal temperature match between glass and mold was obtained.

Glass forming process is a high-volume fabrication method for producing glass containers. In this paper, the mechanisms of glass forming process were analyzed. Combined the coupled thermo-mechanical analysis with the finite element method (FEM) simulation, it was carried out to analyze the key process factors such as forming temperature, forming pressure, friction coefficient. The results show that forming pressure has the greatest influence on the stress.

Stainless steel; Aspheric mould; Ultra-precision turning; Magnetorheological polishing Abstract. The ultra precision turning and the inclined-axis type of magnetorheological polishing were introduced for the small aspheric mould of stainless steel. The method was based on the principle of two kinds of processing methods, and the processing feature of stainless steel material. Firstly, the ultra-precision turning was employed to shape aspheric surface rapidly and obtain a relatively good surface. And then, the inclined-axis type of magnetorheological polishing as the final finishing was used to decrease sub-surface damage to obtain better precision. Several of experiments were carried out, the experimental results show that surface roughness can be achieved for Ra 0.0073μm.

In traditional manufacture of grinding wheel, a key problem is the randomly arrangement of the diamond abrasives, which results in randomly distribution of surface roughness. In this paper, through controlling the magnetic field during the forming process of the grinding wheel, arrangement of diamond abrasives is orderly to obtain a more orderly surface roughness. The forming process of diamond fine grinding wheel is studied under magnetic field controlling. The grinding experiment for aspherical mold was carried out on the tungsten carbide YG8 and the surface quality after grinding was also analyzed

Glass lens molding is a high-volume fabrication method for producing optical components. In this paper, combined with the orthogonal test method and finite element method (FEM) simulation, the coupled thermo-mechanical analysis was carried out to analyze the key process factors. In order to reduce the testing time, an orthogonal test with three sets of level factors and three parameters is conducted to obtain the optimal molding process parameters. The result shows that the most significant parameter is molding velocity, the other effect parameters are molding temperature and friction coefficient. According to the previous analysis of orthogonal experiment, it is shown that the best optimal finishing process parameters were A2B1C1.

Car camera lens is widely used for the safety system of all kinds of vehicles. The car lens should have very wide field angle, strong ability to endure vibration and thermo-mechanical instability as well as erosion. According to these requirements, a new car lens is designed based on the aspheric glass lenses. The whole structure of car lens contains six separated glass lenses including two aspheric lenses. To reduce the cost, the aspheric lenses are made from low-Tg glass which is adaptable for mass production by glass molding press. The total track of lens is less than 30mm. For the enhancement of night vision, the F-number is set to be 2.4. The full FOV (field of view) of 160 is wide enough to capture all the dangerous information around the car. The imaging resolution is designed to be 3 Mega pixels. The designed result proves that the new car lens features high imaging quality. Its MTF (modulation transfer function) value is not less than 0.15 at the Nyquist frequency as for the field angle of 160. At the half Nyquist frequency, the MTF values of the most field angles are not less than 0.5. Therefore, the new lens could be used in the front of car to monitoring the dangerous cases around the corner.

Analysed three design standards on the combination of wire breakage load and the value of tension load over the past decade , According to 1M module of State Grid Tower "typical design-110kV transmission line volumes", selected a straight pole and a corner pole to carry out comparative studies, mainly calculated and analyzed the towers bending moments on the different standards or codes of wire breakage situation and wire breakage tension changes , discussed the change of safety factors of lines’ impact on the tower's bending moments; analyzed synthetically the changes of the pole actual bending moments and weight resulting from inequable ice-coating and other load combination; finally drew a conclusion that national standard increased the tower design standards, and project investment corresponding increased, then put forward reasonable proposals considering the security and economic aspects. Analysis and study are very meaningful and valuable to the different parts of towers calculation and checksum.

The calculated aerodynamic power by using formulas in references is always much less than practical one. The reason was found through analyzing the transformation of mechanical energy output by the motor to heat energy of the whole system and motion energy of the air newly getting in based on the relations of moment equilibrium. New formula of aerodynamic power and equation of air following flow ratio were deduced for closed chamber and holed chamber geotechnical centrifuges. The aerodynamic powers of one constructed closed chamber geotechnical centrifuge and one constructed holed chamber geotechnical centrifuge were computed by using different formulas and the results were compared with each other as well as the practical values, respectively. The comparisons show that the new formulas are much more accurate than previous ones in references.

In this paper, ZnIn2S4 crystals are synthesized in one step at 45°C~65°C by using hydrothermal method and the sample is identified via such technologies as scanning electron microscope, x ray diffraction and UV-visible spectrum. The results show that: hexagonal structured crystals can be prepared at the above-mentioned synthetic temperature; as to the sample obtained at 65°C, its average grain size is about 20~50um and it has a petal-like surface. Taking this ZnIn2S4 microsphere as a catalyst to catalyze the degradation of methyl orange under visible light, the degradation rate of the methyl orange after 2h illumination is above 97% and 100% after 2.5h. This indicates relatively high activity of degrading methyl orange.

Phytoextraction has been recognized as an alternative technique for the remediation of wetland contaminated by heavy metals. The objective of this paper is to investigate the characteristics of heavy metal phytoextaction by phragmites australis and the distribution in soils and phragmites australis of 13 sampling points distributed in fields of Zhaoquanhe, Yangjuanzi and Dongguo in Liaohe estuary.The results showed that the content of heavy metal of Cu and Zn is close in the three phragmites australis fields. The content of heavy metal of Pb in Dongguo field is higher than the others. The content of heavy metal of Cd is lowest for all the heavy metals in the three fields. For the content of heavy metal in different layer soils in the three phragmites australis fields, the content of heavy metal of Cu, Pb, Zn in soils of 0-10 cm, 10-20 cm is higher than in other layer soils. for Cd in soils of 0-30 cm is higher than in other layer soils. And the content of heavy metal in siols of 30-40 cm is lowest for all the heavy metals. The transfer and interaction of Cu, Zn, Cd and Pb in the soil- phragmites australis systems in the three fields is studied, the content of heavy metal of Cu, Zn, Cd is that soils>phragmites australis of aerial part>phragmites australis of underground part, and for the content of heavy metal of Pb, soils>phragmites australis of aerial part≈phragmites australis of underground part. The biological concentration factor of heavy metal of Cu, Zn, Cd is low and transfer coefficient is high relatively .

In this paper, we selected printofix pigment produced by Clariant to print the Cashmere fabric. The effect factors of rubbing fastness and handfeel in the printed fabric, such as baking temperature, baking time and the dosage of binder, thickener and fixing agent etc, were deeply analyzed by extensive experiments. Experiments show that this series of coatings and related agents can get better color rubbing fastness and handlefeel. Finally, we optimized the printing technology to achieve the desired color rubbing fastness and handfeel.

In order to study the comparison of material design, structure design and integrated design about the porous material, a concurrent topology optimization design model associating materials and structures with periodical microstructures is presented. The sensitivity formulae of hierarchy optimization are given based on the integrated design model and related numerical experiments were carried out. The applicability of hierarchy optimization is discussed and their advantage and disadvantage are analyzed through numerical examples which provide some useful opinions about the porous material design.

The sensitivity of blast pressure of a pressure vessel to the material strength, the effective welding depth and the relative radius is studied by finite element simulations and single-factor sensitivity analyses. And the sensitivity coefficients are obtained by normalization procession. Furthermore, a three-factor regression model is obtained by multi-factor numerical experiments. The investigation of this paper provides guidelines for further researches of relating problems.

The bolt-flange structure is most one of joint mode, and stress and mass are its major performance parameters. The multi-object optimization of a bolt-flange structure can be performed by using Finite element method and optimization method unitedly. The response surface design method was employed to determine the combination of geometrical parameters to be designed of the bolt-flange structure. The stress of the bolt-flange structure which has the different geometrical parameters was numerically simulated and analyzed by using the software ANSYS. The response surface model is obtained. The optimized geometrical parameters of the bolt-flange structure were obtained by using MATLAB multi-objective optimization method. The results showed that the maximum equivalent stress in the optimized bolt-flange structure decreased 13.4% than that in the original one and the mass of the optimized bolt-flange structure was lower 14.3% than that of the original one.

Solid - liquid Equilibria for the quaternary system Na2B4O7 - Na2SO4 - K2B4O7 - K2SO4 - H2O at 323K were studied experimentally using the method of isothermal solution saturation. Solubilities and densities of the solution of the system were measured experimentally. On the basis of experimental data, the phase diagram of the quaternary system was constructed. In the equilibrium diagrams of the quaternary system Na2B4O7 - Na2SO4 - K2B4O7 - K2SO4 - H2O at 323 K, there are three invariant points F1, F2 and F3, seven univariant curves E1-F1, E2-F1, E4-F3, E5-F3, E3-F2, F1-F2 and F2-F3, and five fields of crystallization corresponding to Na2B4O7·10H2O，K2B4O7·4H2O，Na2SO4，K2SO4and Na2SO4·3K2SO4. The experimental results show that sulfates have bigger solubilities than borates in the quaternary system Na2B4O7 - Na2SO4 - K2B4O7 - K2SO4 - H2O at 323K.

Presently, there are a significant number of investigations that study the influences of the hydrogen embrittlement on pressure vessels for hydrogen storage. But few of them consider the effects of helium-3 decayed from hydrogen. This paper studies the effects of the high-pressure hydrogen on mechanical behavior of a kind of steel pressure vessel by elastic-plastic finite element simulations, based on the explosion tests data of 4-, 6-, 14- and 17-year hydrogen storage vessels and relating experimental data of materials properties. Then the mechanical responses of the 50-year hydrogen storage pressure vessel are predicted. The results provide guidelines for design and evaluating hydrogen storage vessels.

This article presents a research on friction and wear properties of titanium composite lubricating grease containing ultrafine PTFE particles by using scanning electron microscopy to observe surface morphology of the worn steel balls and EDS to analysis the main elements in the worn surface of steel ball. The results show that the compound titanium grease with 3% ultrafine PTFE has the best wear and friction reduction properties. Its friction coefficient decrease about 25.5%, the diameter of wear scar decrease about 23.2%. The appropriate amount of PTFE particles go into the frictional surface with the grease, form the PTFE particle layer on the frictional surface, which reduces the direct contact of metal to metal, effectively reduces the friction and wear.

A new experimental project was adopted for the special hot-work of pure Cu, which used the execrable condition of high-temperature and high-pressure environment in bore of artillery. Specimen of Cu was prepared from rotating band of sand projectile which had been shot out. Microstructure of Cu after instantaneous extrusion and high speed friction were observed by scanning electron microscopy (SEM). Severe plastic deformation (SPD) and recrystallization phenomena were researched. The analysis results are as follows. At the beginning of SPD, under the instantaneous compression, the surface layer of metal became fibrous tissue with the phenomena of work-hardening. Many oblique strip grains appeared between equiaxed grains and fibrous tissue. With the continuous plastic deformation, temperature of metal improved rapidly under the high speed friction. Recrystallization occurred on the outermost part of fibrous tissue due to heating, so sub-grains gradually became homogeneous equiaxed grains. In addition, SPD had little effect to the inner structure, which is full of equiaxed grains still. All above work could support the research of microstructure of Cu on certain extreme particular environment.

It is well known that structural behaviors of composite solids are determined by topology of microstructures of different sizes. In this paper a concurrent topology optimization method for integrated design of materials and structures with periodical microstructure was presented. The microstructures were assumed to be uniform in macro scale and heterogeneous in micro scale and the optimization object was to minimize the material global compliances. Design variables for structure and material microstructures were defined, independently. SIMP (Solid Isotropic Material with Penalization) was adopted to ensure clear topologies in both macro and micro scales. Design variables for structure and material microstructures were integrated into one system by using the super-element method. Influences of Representative Volume Element sizes, material ratio of macro-scale and micro-scale on structural topology are investigated. Numerical experiments validate the proposed method which can be used as an innovative design concept for the lightweight structures.

The uniaxial tensions of single crystal Cu nanowires (NWs) with different circular cross-section radiuses are simulated by molecular dynamics (MD) method. Atomic interactions in Cu NWs are described by EAM potential. The results show that the plastic deformation of NWs under uniaxial tension is dominantly controlled by dislocation nucleation and gliding. The mechanical properties of NWs are size-dependent. The NWs with larger radius of cross-section possess higher strength and ductility. Furthermore, the site of neck formation and following break of NWs has strong dependence on size scale of NWs.

It is well known that structural behaviors of composite solids are determined by topology of microstructures of different sizes. In this paper a concurrent topology optimization method for integrated design of materials and structures with periodical microstructure was presented. The microstructures were assumed to be uniform in macro scale and heterogeneous in micro scale and the optimization object was to maximize the material fundamental frequency. Design variables for structure and material microstructures were defined, independently. RAMP (Rational Approximation ofMaterial Properties) was adopted to ensure clear topologies in both macro and micro scales. Design variables for structure and material microstructures were integrated into one system by using the super-element method. Influences of Representative Volume Element sizes, the microstructure configuration and macro arrangement are investigated. Numerical experiments validate the proposed method which can be used as an innovative design concept for the lightweight structures.

This paper reported a deterministic method to predict geometrical interferences between grinding wheel and workpiece on ultra-precision grinding for micro aspherical lens mould. An inclined axis grinding mode controlled by B axis is considered and investigated. For avoiding the interference between the grinding wheel and the workpiece, the relationship of the radius of the grinding wheel should be analyzed in the grinding process. In this paper, a geometrical mathematical model for avoiding interferences between grinding wheel and workpiece is built up, and three interference conditions are analyzed. The maximum diameter of the cylindrical grinding wheel is computed and obtained for grinding axisymmetric aspheric surface.

Finite element method and optimization method are two major ones in engineering analysis. The optimization of a wedged-ring joint structure can be performed by using these two methods unitedly. The response surface design method was employed to determine the combination of geometrical parameters to be designed of the wedged-ring joint structure. The stress of the wedged-ring joint structure which has the different geometrical parameters was numerically simulated and analyzed by using engineering software ANSYS. The optimized geometrical parameters of the wedged-ring structure were obtained by using MATLAB multi-objective optimization method. The results show that the maximum stress and the mass of the optimized wedged-ring structure decrease 13.6% and 12.5%, respectively.

Glass lens molding is an effective approach to produce precision micro aspheric glass lens at high efficiency. In this paper, a new two-step isothermal glass molding process was proposed. The mechanisms of new molding process were analyzed. Finite element simulation was conducted to analyze the key factors such as the pressing load, die damage, molding time and residual stress of lens during the traditional molding and the two-step isothermal molding. The results showed that the two-step isothermal glass lens molding process may decrease residual stress and improve stress and strain distribution. Furthermore, prolong the service life of die.

This paper reports a systematic investigation of a nozzle-type ELID grinding characteristics of cemented carbides. Two groups of experimental scheme were carried on by using fine grain cast iron diamond wheel and nozzle-type ELID grinding apparatus. The grinding forces were measured by a dynamometer and the ground surfaces were characterized using scanning electron microscopy (SEM) and atomic force microscope (AFM). The influences of electrolytic and grinding parameters on grinding force were discussed. The material removal mode and micro-morphology characteristics were also analyzed.

Fatigue crack growth was simulated by using a newly developed unified model on the fatigue initiation and crack growth based on an incremental multiaxial fatigue criterion. The cyclic elastic-plastic stress-strain field was analyzed using the general-purpose finite element software (ABAQUS) with the implementation of a robust cyclic plasticity theory. The fatigue crack growth rates with respect to three different stress ratios were selected as the benchmark to check the unified model. The predicted results agreed with the experimental data very well. The insensitivity of the crack growth rate to the stress ratio is due to the fast mean stress relaxation.