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The complex [Dy4(L1)2(CH3COO)4(DMF)3] (1) was obtained by using 2,6-bis(2-((E)-(8-hydroxyquinolin-2-yl)methylene)hydrazine-1-carbonyl)pyridine 1-oxide (H4L1) and Dy(CH3COO)3·4H2O under 100 in N,N-dimethylformamide (DMF) solvent. Structure analyzing showed that Dy(III) ions had two types of configuration with D2d and C4v. AC magnetic susceptibilities exhibited that complex 1 was an obvious single-molecule magnet (SMM) with obvious ac susceptibilities at zero Oe static magnetic field over the frequency range of 9–999 Hz. These findings demonstrated potential applications of polydentate ligands for the synthesis of SMMs.

We successfully obtained two type of heterometallic complexes [Fe4Dy2(L1)2(µ4-O)2(piv)4(H2O)2(NO3)4]·CH3CN·CH3OH (1) and [Fe6Dy2(L1)2(µ4-O)2(CH3COO)6(OH)2(H2O)2(NO3)6]·CH3CN (2) by using 2,2′-((2-((2-hydroxyethyl)amino)cyclohexyl)azanediyl)bis(ethan-1-ol) (H3L1), Dy(NO3)3·6H2O, FeCl3 and pivalic acid (piv) or acetic acid under room temperature in different solvent. Crystal structure showed that the central structure of [ $${{\text{Fe}}}_{4}^{{\text{III}}}$$ (µ4-O)2]8+ arranged in what was often termed an absent cubic shape, although here the Fe centers were strictly coplanar. Each Fe3 triangle was connected to the capping Dy(III) through µ4-O bridges for complex 1, and each Fe3 triangle was connected to the capping Fe(III) through µ4-O bridges for complex 2. It might be due to the steric effect that the coordination atoms of piv ligands chelated and blocked the structure. AC magnetic susceptibilities exhibited that complex 1 and 2 showed out-of-phase (χ″) component of ac-susceptibilities at zero Oe static magnetic field over the frequency range of 9–999 Hz, which energy barriers were 0.44 and 0.13 K. And their energy barriers were 1.2 and 12.2 K at applied 1000 Oe static magnetic field.

Today, sub-0.1 V and sub-0.1 mW VCO is not available mainly due to inductor/transistor limitations. Here, the designed 5-GHz VCO using the proposed L/Q-booster demonstrated a P DC of 0.051 mW, and achieved a FoM of 190 dBc/Hz at 0.1 V supply voltage. The VCO can operate even down to 0.05 V under a P DC of 0.036 mW. The proposed booster not only enhances the inductor Q by more than 10×, but also L by 2× to save chip area. As a result, a VCO core area of 0.047 mm2 was achieved by using 16-nm CMOS FinFET technology.

High hardness surface coating sphere components are widely used in metal sealing ball valves. The spherical surface grinding texture influences the valve’s tribological performances such as friction, lubrication and wear of interacting surfaces. It can be used to develop the index of grinding parameter optimization. In this paper, based on the discussion of sphere generating grinding methods, the surface grinding texture is quantitatively analyzed. The space trajectory of abrasive particles during sphere grinding is studied. The trajectory mathematical models are built based on two kinds of sphere grinding manners and are verified by comparing the theoretical results against experimental measurements. The influence of grinding parameters on the texture is analyzed. Texture density are defined to quantitatively describe the surface texture. The relationship between grinding texture and ball valve performance is finally discussed. The conclusions can help to optimize the spherical surface grinding process.

In this paper, the birch flour was the raw material with its particle size less than 100μm and the polyester hot-melt adhesive was used as binder with its particle size less than 60μm. The birch flour was dried using high speed mixer with heating function. The birch flour/polyester composite were prepared using the physical mixing method. The surface of the specimen and fracture surface of specimen were analyzed through the micrographs of scanning electron microscopy. In order to study the characteristics of laser sintering, the preheating temperature of the powder bed of laser sintering machine and the processing parameters of the birch flour/polyester composite were determined using single layer sintering method and empirical method. The tensile, flexural and impact specimens were built in the two scanning laser ways of subarea scan and progressive scan. The testing results show that the mechanical properties using subarea scan method are superior to those of progressive scan method and the mechanical properties of the specimens increase as the laser scan speed decreases. The best mechanical properties of SLS specimens of brich flour/polyester composite powder were obtained with the following parameters: the laser power was 11W, layer scan speed was 1800mm/s; layer thickness was 0.1mm; laser scan spacing was 0.1mm and the average tensile, flexural and impact strength of specimens were 1.35MPa, 3.69Mpa and 0.73KJ/m2 respectively.

Bamboo flour is a kind of a cheap reproducible natural plant powder. The polyamide hot melt adhesive (polyamide) is good bamboo adhesives. The bamboo flour/polyamide blend is prepared through mechanical mixing method. The powder bed preheating temperature of the laser sintering processing and the processing parameters of bamboo flour/polyamide blend are determined through the differential scanning calorimetry method (DSC method) and single layer sintering experiment. The mechanical testing parts are successfully fabricated by selective laser sintering using the bamboo flour/polyamide blend of 25/75 (wt/wt). In this series of experiments, the average tensile strength, flexural strength and impact strength of 5.9Mpa、11.5Mpa and 4.5KJ/m2 are obtained when the laser power is 11W, scan spacing is 0.1mm, the thickness of a layer is 0.1mm and scanning speed is 2000mm/s. The tensile strength and flexural strength of the SLS specimens are improved through wax infiltrating process, while the average impact strength of the wax-infiltrated specimens decreases compared with the SLS specimens processed under the same set of parameters. Bamboo flour/polyamide composite powder is new laser sintering with good forming property and low cost.

The dynamic viscoelasticity of the outer and inner part of bamboo with different ages was investigated using Dynamic Mechanical Thermal Analyzer (DMA). The results showed that,storage modulus (E’) and loss modulus (E’’) of both outer and inner part of bamboo were increased at temperature between 25-250°Cas the bamboo ages increasing. In addition, E’ and E’’ of the outer part of bamboo were higher of the inner part with the same bamboo age. Also a significant loss peak in E’’~T curves between 190-210°C was found. The peak values of E’’~ T curves of the outer part only shown slight variation with bamboo age increasing. However, significantly different of peak values was found in the inner part. This was caused by the difference of the chemical composition in outer and inner part of bamboo with different ages. The width of E’’ peak varied slightly in outer bamboo of different ages, but in the inner part , it was increased as the age increasing. This revealed that in the outer part of different ages, the chemical composition of the molecular values was closer, In the inner bamboo, it was increased as the age increasing..

In this paper, the behavior of composite stub columns under different loading conditions is studied using the finite element method. The accuracy of the theoretical method is validated by comparing with the experimental results. The behavior of specimen under different loading conditions is analyzed. Then, based on the finite element method, the comparison of mechanical behavior under three typical loading conditions is studied. The results show that the difference on bearing capacity will become larger with the increase of steel area to concrete area ratio. For the core concrete loaded specimen with lower steel area-to-concrete area ratio, whose bearing capacity is the lowest, but its ductility is very good. With the increase of the steel yield strength, the bearing capacity will increase evidently for specimen loaded simultaneously. While for the specimen with only core concrete loaded, the steel yield strength has little influence except increase of ductility.

The dynamic mechanical properties of radial and chordwise bamboo pieces were tested by dynamic mechanical analysis (DMA). The results show that the storage modulus and loss modulus and tangent delta of chordwise direction were all larger than the radial direction of bamboo; the peak of glass transition temperature of chordwise direction is high than the radial direction, and their sizes are very close; dynamic mechanical analysis can provide a reference for the optimization applicable environment temperature of curtain plybamboo.

Subjected to external pressure, buckling analysis is key problem in the roof shell design of large scale cylinder gasholder. Two simplified buckling analysis methods, the continuous orthotropic plate method and the split-rigidity method, are introduced to check the general instability of stiffened spherical shallow shell. Considering the plate and the stiffeners in two directions with the same contribution to the bending stiffness, the equivalent bending thickness formula is put forward. The finite element model for a 100,000 m³cylinder gasholder roof is setup. The buckling critical loads obtained prove that the split-rigidity analysis method and formulae are applicable. The results can be referred in design of stiffened spherical shallow shell.

This paper presents the studies on surface contact angles of water and phenolic resin and bonding strengths of three kinds of radial bamboo strips and chordwise bamboo strips. The results showed: water and phenolic resin could better wet radial bamboo strips, and wettability and gluing properties of the base radial bamboo strips were best, the middle radial bamboo strips followed, the tip radial bamboo strips ranked third in the three kinds of radial bamboo strips; wettability of water and phenolic resin and gluing properties of chordwise bamboo strips were better than radial bamboo strips.

In this paper, the influence of the tool rake angle, cutting depth and cutting speed on exit edge defect sizes are discussed by the two dimension cutting experiment of SiCp/Al composites. The sizes are measured by using the Keyence VHX-1000C type super preview 3D microscopy. The results indicate that exit edge defect sizes are influenced greatly by tool rake angle and cutting depth, and are influenced slightly by the cutting speed. The edge defect sizes have an overall downward trend when the tool rake angle is smaller than 5°, and have an apparent upward trend when the tool rake angle (γ0) is 10°.The length (L), height (H) of exit edge defects and the negative shear angle increase with increasing of the cutting depth.

Cr(III)-containing wastewater was treated by continuous foam separation process. The factors affecting the Cr(III) removal efficiency were researched. The optimal operating conditions determined by orthogonal experiments are as follows:wastewater pH 6.50,gas flow 400ml/min,cationic surfactant dosage 50mg/L.When the mass concentration of Cr(III) in the influent is 7.5mg/L,the effluent can meet the national discharge standard with 98% of Cr(III) removal rate for continuous running. The kinetic experimental results show that the foam separation of Cr(III) accords with the first order kinetic equation. The results of continuous experiments in a scale-up foam separation column indicate which reach the Second Wastewater Discharge Standard of Country.

One novel highly cross-linked, shape-controllable molecularly imprinted sol-gel film (MISF) with good thermal and chemical stability and three-dimensional network porous structure has been developed. The binding characteristic of the imprinted film to bifenthrin was evaluated by equilibrium binding experiments and imprinting-induced promotion of binding. The MISF was modified into the wells of 96 micro-well plate combined with chemiluminescence (CL) technology to establish the molecular imprinting-chemiluminescence (MI-CL) sensor. The high throughput and high selective detection sensor of bifenthrin was applied in vegetable and food samples with satisfactory results.

The different age pleioblastus amarus particle were taken as the raw materials, and the wet-process bamboo powder-boards were made from the laccase-treated powder by hot pressing. The raw material chemical constituents were analyzed. The reactive oxygen species free radicals produced from the laccase-treated bamboo were detected by electron spin resonance. The physical and mechanical properties of the bamboo particleboards were measured. In order to provide some theoretical basis for producing bamboo particleboard by laccase activation, the relations between physical and mechanical properties of bamboo particle boards and chemical constituents, the reactive oxygen species free radicals were researched.

Cement concrete has an increasing utilization in highway construction. However, the lower flexural tensile strength and abrasion-resistance restricted the development of concrete pavement with heavy traffic. Hence, It has highlighted the need for research on high performance concrete (HPC). The design of specific concrete normally depends on the mixing of mineral admixtures in concrete mixture. This paper presents the first experimental study on strength and abrasion-resistance enhancement admixture (SAEA) mixed with slag powder, steel slag powder and silica fume. The optimal proportion of three mineral admixture and reasonable mixed amount of SAEA were then given, and the mechanism of SAEA reacted in concrete was analyzed based on sol-gel theory. Lastly, the effect of concrete mixed with SAEA was validated and the micro-structure transformation of specimens was given by SEM.

The processing technique of bamboo particle board using laccase-treated calcium lignosulfonate was investigated and optimized. We studied the influence of enzyme amount, calcium ligosulfonate amount and hot pressing temperature on different particle board properties. All three factors were significant difference at different levels. There has significant differences between enzyme amount and Modulus of Rupture (MOR)，Modulus of Elasticity (MOE), Thickness Swelling (TS) (P

Three kinds of particles which produced by the processing of bamboo flooring were taken as the raw materials and analyzed of chemical constituents. Cellulose crystallinity and the reactive oxygen species (ROS) free radicals produced from laccase-treated bamboo were examined by X-ray Diffraction (XRD) and Electron Spin Resonance (ESR), respectively. Physical and mechanical properties of laccase treated bamboo particle boards which made from surplus materials of bamboo flooring process were investigated. In order to provide some theoretical basis for producing particle board with the surplus materials of bamboo flooring process by using laccase, the relations between physical properties and chemical constituents, cellulose crystallinity or the ROS free radicals of bamboo particle boards were researched.

The ways of chemical component analysis, chemical analysis photoelectron energy spectrum (ESCA) analysis and X ray diffraction were used to research and analyze the variation law of material (wood) chemical component, functional groups and cellulose crystallinity in the process of making board. The results showed that：(1) The maximum contents of holocellulose and pentosan were wood, in the next place were fiberboard, and the minimum one were binderless fiberboard. The maximum contents of α-cellulose were woodfiber, in the next place were wood, and the minimum one were binderless fiberboard. The minimum contents of xylogen were wood, in the next place were woodfiber, and the maximum one were binderless fiberboard. (2) The C1and C3 functional groups relative contents of woodfiber and binderless fiberboard were higher than wood. The C2 functional groups relative contents of wood were higher than woodfiber and binderless fiberboard. The C4 functional groups relative contents of woodfiber were zero, and the binderless fiberboards were higher than wood. (3)The maximum cellulose relative crystallinity was binderless fiberboard, in the next place was fiberboard, and the minimum one was wood.

Thermagravimetric and combustion characteristics of binderless fiberboard (BF) were investigated. Fibers prepared by traditional heat grinding (FB) and which prepared in the presence of trivial inorganic acid during grinding (FBA) were used as compared. The results show that the total weight lost during thermal decomposition following as: BF > FBA > FB. The order of initial decomposition temperature was that FB > BF > FBA. Thermagravimetric weight loss rate in pyrolysis of woodfiber and binderless fiberboard got from adding minim inorganic acid in the heat grinding system to heat grinding were faster compared to the woodfiber made by heat grinding. Combustion characteristics results revealed that heat release rate and total heat release amount of BF were larger than that of FB. Smoking ratio of BF was larger than that of FB before the flaming combustion, but t less than that of FB after the flaming combustion. The concentration of produced CO2 and CO for BF during combustion was higher than FB.

Plybamboo is commonly made using chordwise bamboo strips. Previous studies have indicated that the bamboo utilization rate and the processing efficiency are low in manufacturing chordwise curtain Plybamboo. This paper presents a study on the manufacturing technology of radial curtain plybamboo form. Radial strips cut from bamboo were glued on the radial faces. The results showed: (1) the bamboo utilization rate of radial cutting strips was 15-20% higher than chordwise cutting strips, and the resin consumption was only approximately 50% of chordwise bamboo strips; (2) however, radial bamboo strips were more subject to lengthwise bending deformation than chordwise strips during drying. This lengthwise bending deformation can be effectively reduced or prevented by placing a hollow rigidity axle in the radial bamboo curtain rolls when using the bound drying method; (3) the hot pressing time of the radial curtain plybamboo form was approximately 50% of the chordwise composite plastic curtain plybamboo.

Grinding is an energy-intensive process in which the heat generated can cause various types of thermal damage to workpiece. Many theoretical, empirical or numerical models have been developed to predict grinding temperature. However, these models are not directly applicable for coated workpieces. Tools or other parts are coated with hard materials like tungsten carbide, ceramics or polycrystalline diamond to increase their surface hardness and prolong their life expectancy. In this paper, an empirical model is proposed to predict the maximum grinding temperature of coated workpieces. Experimental and numerical studies are carried out to validate the model. The results indicated that the new model is able to accurately predict grinding temperature.

Laser rapid forming is a kind of new developed technology combining laser surface modification and rapid prototyping technology. It provides a powerful tool for the manufacturing and repairing of metal components. Laser rapid forming repairing experiments of 45 and 2Cr12 steel have been carried out with 316L stainless steel powder. Microstructure and properties of the repaired components are analyzed and tested with optical microscopy (OM), scanning electron microscopy (SEM) and electronic tensile experimental machine etc. Repaired components of different materials have been metallurgically bonded with the deposited layers, with fine microstructure, better mechanical properties and free of defects.

This paper presented a new technique, which was the online wear evaluation of wheel in grinding WC-Co coating by using wavelet packet decomposition. Based on the measurement method, theory of online wear evaluation of wheel was introduced. The selection principle of characteristic signals was brought up, and the grinding acceleration signal was the best choice among many characteristic signals. The time domain signal analysis method of wavelet packet decomposition was analyzed. Lastly, experiments on the wear of wheel were performed, and experimental results showed the validity of the method.

Polycrystalline diamond (PCD)-coated tungsten carbide (WC) is a high-performance cutting tool material widely used in industry for cutting or ultra-precision cutting of advanced engineering materials, but it is difficult to machine using conventional machining techniques owing to its high hardness. However, wire electrical discharge machining (wire EDM) offers advantages in machining PCD-coated WC in terms of process reliability and flexibility to machine different shapes. To relieve pollution issues associated with traditional wet wire EDM, the present study investigated the feasibility of near-dry wire EDM of PCD-coated WC cutting tool material using deionized water and air mist. A parametric study on spark cycle and spark duration was carried out, and the effect of these two important wire EDM process parameters on machining performance in terms of material removal rate (MRR) and surface roughness ( Ra) was analysed. Compared with conventional wet wire EDM, near-dry wire EDM consistently produces better Ra values on the PCD-coated WC workpiece, but near-dry wire EDM produces lower MRR than wet wire EDM under some conditions.

Multi-walled carbon nanotubes (MWNTs)-Fe3Al was prepared by spark plasma sintering. Microstructural investigations show that MWNT remains in the composites. The magnetic properties were investigated with alternating gradient force magnetometer, which shows that the composites still display good soft magnetic property. The MWNTs-Fe3Al composites have a similar magnetic hysteresis loops to that of Fe3Al, indicating the good soft magnetic properties of the composite. Excellent magnetic property implies that MWNT-Fe3Al composites may also have significant potential for applications in electronic-magnetic nanodevice fields.

Ferromagnetic resonance for magnetic thin films is found to be coexisted with the trans- mission resonance of a T-type microwave microstrip at certain applied magnetic fields. The frequency dependence of conductivity, the magnetization, and the magnetic anisot- ropy of magnetic films can be eventually solved from the measured resonance frequency and quality Q factors of the resonance spectra. Equivalent resistances (R), inductances (L), and capacitances (C) corresponding to the displayed transmission S21 spectra are sim- ulated to comply with proper values. With this equivalent circuit, an accurate determina- tion of the magnetic properties can be closely scrutinized.

The technology of superabrasive grinding has been developed in order to achieve high-quality finish in extremely hard and brittle materials. Thereafter, truing and dressing technology on super abrasive grinding wheel is one of the most important subjects on precise machining field at present. In this paper, mist-jetting electrical discharge technology was applied to dressing metal-bonded superabrasive wheels. And a systematical study on the mechanism of selective removal of the bond was proposed. Experiments on dressing bronze bonded diamond grind wheels were carried out on a die-sinking electrical discharge machine. The diamond wheel topographies before and after electrical discharge dressing were observed by VH-800 3D digital microscope. The wheel profiles before and after dressing were observed. The results of electrical discharge dressing under different electrical parameters were compared. Experimental results indicate that the favorable surface topography can be obtained under suitable processing parameters and mist-jetting electrical discharge dressing (MEDD) is feasible for metal-bonded diamond grinding wheel.

To investigate the effect of micro-topography on the wear properties of the cold roller, rough surface was characterized with fractal geometry, and the profile of laser-textured surface was measured based on the analysis of surface profile self-similarity, feasibility of fractal characterization of the surface was studied with power law method. Results show that Isotropic surfaces tend to be fractal and surfaces processed under definite technological conditions can be characterized with fractal geometry. On this basis, effects of surface fractal parameters on the wear rate of the roller were analyzed with fractal geometry model for wear prediction. Condition of achieving optimal fractal dimension was presented and the expression of the optimal fractal dimension was derived for the minimum normalized wear rate. It shows that normalized wear rate is mainly determined by fractal dimension besides the material properties and an optimal fractal dimension existed for the engineering surface is affected by the plastic index, normalized true contact area and scale coefficient. The results will provide bases for the studies of friction and lubrication of the textured steel sheet and guidance for the actual processing.

The surface texture of sheet steel plays an important role for automotive applications. To achieve appropriate surface topographies and press-forming behaviour, a new laser coating texturing (LCT) technique aimed at texturing steel work-rolls was proposed. The laser texturing process was realized by applying laser pulses at very high repetition rates to produce innumerable micro-craters with the required shape profile on the surface of the rolls. Moreover, the surface alloying of the dimples was carried out on the substrates of bearing steel GCr15. The submicron WC-Co alloy metal powder was melted into the micro-craters by high laser energy. The effects of processing parameters on the properties of the laser textured samples were investigated. The dimpled surfaces were examined by a 3-dimensional surface profilometer. Microstructures of the coating layers were assessed by optical and scanning electron microscopy. The experimental investigations show that the laser-dimpled hard-coated surfaces exhibit compatible metallurgical interfaces with the substrates. The laser coating textured roll is demonstrated to have excellent abrasion resistance and a much longer service life. The abrasive wear resistance was 5 times higher than that of the substrates. The average surface microhardness values were as high as 700HV.

The processing parameters of laser texturing are linked with the wear property of roller surface based on the relationship between the fractal parameters and surface roughness. The influence of laser power density, scanning speed and pulse width on the roughness is analyzed though experiments. The effect of fractal parameters on the wear rate of the roller is analyzed with fractal geometry model for wear prediction. Condition of achieving engineering surface with optimal fractal dimension is presented and the expression of the optimal fractal dimension is derived. It shows that the roughness of laser textured surface and normalized wear rate are mainly determined by laser power density and fractal dimension, respectively. Moreover, to get the textured surface with smallest nominal wear rate, processing parameters of laser texturing, especially the laser power density, should be controlled properly besides the material properties of the roller. The result will provide guidance for the processing.

This paper presented a new technology, which was the online wheel wear evaluation in grinding WC-Co ceramic coating by using wavelet packet decomposition. On the basis of the measurement methods, theory of online wear evaluation of wheel was introduced. And the selection principle of characteristic signals was brought forward, the grinding acceleration signal was the best choice among many characteristic signals. The time domain signal analysis method of wavelet packet decomposition was analyzed. Lastly, experiments on the wear of wheel were performed, and the experimental results showed the validity of the method.

Ceramic coating materials own some advantages, for example high-rigidity, good abradability and good performance under high temperature. At the same time, ceramic coating materials are also difficult-to-machine materials. High machining precision and efficiency can be obtained in grinding WC-Co coating by cup wheel. The affection of grinding temperature is very important for grinding processing. But there is no research on grinding temperature of WC-Co coating by cup wheel. So in this paper, grinding temperature by cup wheel is researched on theory, the new concept, which is effectiveness width of arc moving heat source, is presented, and theoretical formula of grinding temperature is also built. Then experimental research on grinding temperature of WC-Co coating by cup wheel is done by use of thermocouple temperature measurement technology. The experimental results show the validity and effectivity of the theoretical formula. The affection of grinding parameters to grinding temperature is researched also.

In traditional NC curve grinding, the grinding wheel’s rotary surface is generally not on the grinding point’s normal direction, which will bring the distortion of grinding wheel and decrease the machining precision. This paper presents a new technology, which is called the non-interference normal tracking for NC curve grinding process. By controlling the worktable to rotate in the x-y plane, the superposition between the rotary surface of the grinding wheel and the normal vector of the workpiece’s contour is realized, and the interference between the wheel’s body and the workpiece could be avoided at the same time. A mathematic model is established and an algorithm to calculate the worktable’s rotary angle is proposed. Finally, the algorithm is applied in a new-type digital curve grinder successfully. The results show that the method is reliable and effective.

Present modeling algorithm for large-sized revolving parts’ camber can not ensure the smoothness, so a new modeling algorithm based on NURBS Curve was proposed in this study. In detail, the new modeling algorithm is as following: Firstly transfer these discrete points, which are measured along the part’s axial lead by equal distant, into a weighting unity sequence. Secondly filter this sequence by wavelet de-noising algorithm. Thirdly replace the discrete points’ amplitudes by the corresponding weights of filtered sequence, thus yield a group of new discrete points. Lastly calculate the control vertexes and weighting factors by local rational interpolation algorithm, and construct a spatial NURBS Curve through the new discrete points to obtain the model of large-sized revolving parts’ camber. It was experimentally confirmed that this model can represent drilling stem’s camber smoothly and improve its pressure straightening precision.

The experimental results for silicon carbide (SiC) wheel with fine grit size grinding of silicon carbide (Si3N4) revealed that the grinding parameters affect not only the ground silicon nitride surface roughness, but also the degree of surface damage. There exists complex non-linear relationship between the grinding parameters and surface quality. Better surface roughness doesn’t surely mean less surface damage. A method of prediction of grinding quality based on support vector regression is then presented according to the condition of small samples. The result shows the prediction accuracy based on this method is obviously higher than neural network, which provides an effective way for optimizing the grinding parameters to ensure the grinding quality as well as grinding efficiency while grinding of silicon carbide using conventional abrasive.

Design, characterization, and modeling of differential semicoaxial interconnects based on a standard 0.18-mum CMOS process are presented for the first time. The differential semicoaxial line shows a low differential-mode attenuation constant of ~1.00 dB/mm at 50 GHz and a slow-wave factor above 3.1 over a wide frequency range. The characteristics of differential semicoaxial lines for differential mode, common mode, slow-wave effect, and coupling effect are also investigated in details based on the measured mixed-mode S-parameters. The lumped RLGC circuit is adopted to model the CMOS differential semicoaxial lines. An excellent agreement between the measured and modeled results is obtained up to 50 GHz

This paper deals with an application for achieving precision curve grinding by automatic dressing and compensation of diamond wheel wear through non-contact measuring method. A realtime vision measurement combined with vibration analysis method for the wear of a grinding wheel is presented. The wear condition is evaluated by analyzing the topography changes of the wheel surface and the vibration signals in the grinding process. A kind of PC-based integrated control system with dynamic monitoring and automatic dressing function is investigated, and the control algorithm is also proposed. The benefits of the proposed methods are confirmed by the grinding experiments. Dynamic monitoring of the wheel facilitates determining the optimum dressing amount and interval. A much higher abrasive machining precision and efficiency are attained by the real-time error measurement and compensation arrangement.

Experimental study on the laser direct fabrication (LDF) of stainless steel powder is carried out. Microstructure and properties of the deposited components are analyzed and tested with optical microscopy (OM), scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) etc. Cracking generation mechanisms of this material are investigated, corresponding cracking control strategies have been proposed. Finally, fully dense stainless steel components free of defects and with perfect comprehensive mechanical properties have been produced.

Both diamond wheel and CBN wheel belong to super-abrasive wheels. Diamond wheels have superior grinding performance. The metal-bonded diamond wheel can grind hard brittle material component with a complicated shape precisely and efficiently. Because dielectric liquid is forbidden on numerical control optical profile grinder, the information on profile truing and dressing diamond wheel mounted on numerical control optical profile grinder is not readily available. In this paper, a novel truing and dressing method, namely dry electrical discharge (dry-ECD) assisted truing and dressing, is proposed. The experiments of dry-ECD assisted profile truing and dressing of diamond wheel are done by the authors. The experimental results show that both geometrical accuracy and surface topography of diamond wheel have attained technical requirement under appropriate truing and dressing conditions. There is not much difference in grinding abilities of new diamond wheel and dry-ECD assisted truing and dressing diamond wheel.

An on-line image measurement system for curve grinding was schemed out according to the working process. Because of interaction between detection precision and field of view, it is difficult to realize high detection precision at a large field of view. In order to settle this problem, a detection method based on circular tolerance zone was presented according to grinding process and wheel shape. Real-time images of work piece can be gathered while using synchronal control and outer trigger technology. Using curve fitting method, the work piece image edge can be located to sub-pixel values. Experiments show that the proposed method in this paper is effective, and its detection precision and results are reasonable.

In order to produce N44SH and N40UH high-grade magnet, both strip casting and hydrogen decrepitation processes were adopted, and the subsequent milling, sintering and heat-treatment processes were improved. The density of N40UH magnet is risen up to 7.65 g/cm c . Weight loss rate after the Highly Accelerated Stress Test (HAST) for 48 hours is less than 0.2 mg/cm b . The microstructure of magnet shows that the grain size is between 5 to 8 μm. The rich-Nd phase is fine and uniform, the pinhole is very few, such magnet can be used for wind power generator after phosphoruster treatment directly, and it can also be used in hydrogen atmosphere of hybrid car after surface treatment.

A bi-harmonic stress function is constructed in this work. Ariy stress function methodology is used to obtain a set of analytical solutions for both ends fixed beams subjected to uniform load. The treatment for fixed-end boundary conditions is the same as that presented by Timoshenko and Goodier (1970). The solutions for propped cantilever beams and cantilever beams are also presented. All of the analytical plane-stress solutions can be obtained for a uniformly loaded isotropic beam with rectangular cross section under different types of classical boundary conditions.

This paper presents the tests of electrical discharge grinding (EDG) of polycrystalline diamond (PCD) on electrical discharge machine tool with high speed rotating device. The effects of wheel speed, open circuit voltage, peak current, pulse on time, and pulse off time of EDG on the material removal rate (MRR), wheel wear rate (WWR) and surface roughness (SR) are investigated respectively. The tests indicate that it is possible to shape PCD blank with EDG. The wheel speed makes the MRR increase dramatically. The higher the open circuit voltage, the larger is the MRR. The effect of peak current on the MRR, WWR and the SR is similar with that of open circuit voltage. However, the influence of the peak current is much larger than that of the open circuit voltage. Moreover, the peak current should be smaller than 32A. There is a best ratio between the pulse on time and pulse off time. If a ratio is larger or smaller than that value, there may be adverse effect on the SR and the MRR. Large pulse on time makes the MRR increase and the WWR decrease. However, all the parameters investigated have little influence on the SR of PCD. The SR is determined mainly by the grain size of PCD.

Rapid manufacturing moulds by plasma arc spraying is a new kind of plasma arc machining technology. This technology has many advantages. An experimental apparatus has been set up. The influence of some special factors on the surface quality of work moulds formed by plasma arc spraying have been analyzed and experimentally researched. The micro structure of the interface between master moulds and work moulds shows that work moulds copy geometrically master moulds very well after optimizing processing parameters. Some experimental samples by plasma arc spraying have been obtained. They show that the surface patterns of work moulds match with the ones of master molds very well.