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Holistic thin-walled parts are common structural parts of modern aircraft to reduce the weight and increase the stiffness. Over 90% of the materials are removed from the blank, as a result, large machining deformations occur to the parts, which causes the manufacturing discrepancies and even the scrap parts. In this paper, numerical simulation models are established to predict the machining deformation of two typical aviation thin-walled parts. The blank initial and machining induced residual stresses, as well as the cutting parameters, are considered in the model. The deformations and stresses after machining are calculated using the proposed model, and the deformation and stress distributions are analyzed.

As one of the most important components of transmission equipment in electric power field, power transformer bears the important task of energy conversion, power distribution and energy transfer. Because generated a huge force in transformer winding by its interior circuit excitation, it would be taken place easily to distortion, collapse and other damage of its structure, which brings a large safe and reliable problem. The lack of mechanical strength of the coil, which cannot withstand the sudden short-circuit current impact, led to the break of insulating layers, is one of the main causes in transformer failure. In this paper, it is discussed that theoretical and experimental study on mechanical force of transformer coil short circuit. According to the structural mechanics, the calculation of the contacted pressure between the coils is attained by building the contacted model. And the experimental system is been designed, which has a servo control system. Compared the theoretical and the Experimental data, the best accurate computed method for contacted pressure is obtained. It is helpful to improve the resistance ability for short circuit of transformer, and provide guarantee for the safe operation of the transformer.

In this paper, a two-stage optimization algorithm is proposed to simultaneously achieve the optimum structure and microstructure of lightweight cellular materials. Microstructure is assumed being uniform in macro-scale to meet manufacturing requirements. Furthermore, to reduce the computation cost, the design process is divided into two stages, which are concurrent design and material design. In the first stage, macro density and modulus matrix of cellular material are used both as design variables. Then, the optimum topology of macro-structure and modulus matrix of cellular materials will be obtained under this configuration. In the second stage, topology optimization technology is used to achieve a micro-structure of cellular material which is corresponded with the optimum modulus matrix in the earlier concurrent design stage. Moreover, the effectiveness of the present design methodology and optimization scheme is then demonstrated through numerical example.

When the partially porous aerostatic thrust bearing and the journal bearings of an aerostatic spindle in a vertical milling machine are subjected to cutting load and gravitational force, the thicknesses of gaps between the thrust plate and the spindle flange will change. This study applied CFD software to analyze the effect of variations of gap thickness and rotating speed on the pressure in the gaps of the bearings and the stiffness of the spindle. The results revealed that, when the thrust plate and the spindle flange were pushed back and forth by external loading, the pressure in the gap between the spindle flange and the thrust plate was affected significantly. The pressure in the gap between the spindle and the journal bearing was slightly affected. When the spindle rotated faster, the pressure on the surface of spindle became higher and the stiffness of spindle was increased.

The influence of the spacing of the partially porous aerostatic journal bearings and the rotating speed of the spindle on the pressure distribution in the bearing gap and the housing gap were studied. Based on the finite volume method and the pressure-velocity coupling scheme of the SIMPLE algorithm with the standard k-ε turbulent model, A CFD software was used to solve the Navier-Stokes equations to figure out the pressure in the bearing gap and the housing gap. The computed results indicated that when the spacing of the bearings between air outlets was increased, the pressure got higher not only in the bearing gap, but also in the housing gap. The load carrying capacity of the bearings and the stiffness of the spindle could be improved. If the spacing of bearings was reduced by adding one more bearing to the location between the original bearings, the pressure in the narrower housing gap would decrease, while that in the wider housing gap would increase. Though the extra bearing could not help increase the net pressure exerted on the spindle effectively, it did help redistribute the housing gap pressure so that the pressure difference in the air gap could be reduced and the spindle was able to rotate stably.

An Al-Zn-Mg-Cu high strength alloy ingot produced by Direct-Chill casting was used in this study. The distribution of porosity in the cross section of the DC ingot was investigated by the precision density method (Archimeds’ principle), also X-ray microtomography technique was used to quantitatively analyze porosities in typical positions. The pattern in the cross section as well as in the thickness and width direction was obtained. The results show that: in the cross section of the ingot, porosity was increasing gradually from the surface to the center of the ingot; porosity shows an overall escalating trend from the surface to the center of the ingot both in thickness direction and in width direction; porosity was closely related to the cooling rate in the ingot; oxide inclusions have an effect on the formation of porosity to some extent.

Present work was carried out to investigate the measurement accuracy of the sump depth for 7050 billet in direct chill (DC) casting process. Three measuring methods were applied: (i) Al-30wt.% Cu melt was poured into the mold at the steady state of the casting attempting to record the profile of billet sump; (ii) two steel rods were vertically dipped into the centreline and the edge of the billet attempting to measure the distances between the solidus and the free liquid surface in the hot-top; (iii) several ordered thermocouples were pre-arranged onto the starting block and they were solidified into the billet as it was cast, and a series of temperature-time curves was recorded after casting. For the purposes of comparison and evaluation, a numerical model based on the same experiment parameters was also built and the simulation results were compared with measured results by above methods. It indicates that the sump depth measured by thermocouples has the best consistency with numerical results. The most accurate method is temperature recoding by thermocouples. The Al-Cu melt pouring method is more accurate than the rods dipping method, and the sump depths measured by later two methods were the positions about the solid fraction (fs) depths of 0.8 to 0.9.

A certain type of special computer was studied as the institute in this paper. Through researching on the structure of the special computer box, use the Pro/E software to create the simplified model of the case, including computer cabinet, PCB, power and fan etc. Model analysis is conducted in the FEA environment ANSYS, attains ten order natural frequency and vibration mode. Dynamic load in the model is applied with half sine impact acceleration, and the resistance performance of the PCB which is the important components of the model is researched by the acceleration, speed and displacement response results obtained. Verify the installation method of vibration isolator can effectively improve the shock resistance of special computer.

The Automatic Test System (ATS) is being increasingly used in the business and professional test. However, there are some potential problems emerged in the application of the distributed test. So we intend to solve the problems by adopting the idea of the Cloud Computing to solve the two challenges: improve the efficient use of the limited and heterogeneous hardware test resources and shorten the test cycle which is defined as the whole time of the test. The paper proposes several structures of the Cloud Test System (CTS): the overall structure, the software and hardware architecture. Theoretically,the study overcomes the challenges of the existing test system, then the foundation of the further study is laid.

Copper stripping machine is an alternative to traditional artificial device. It is one of the key parts of the stripping device. It realizes stripping the sponge copper from the surface of the sheet nickel and ensures the subsequent automation. This article has carried on the simulation by using ADAMS to the movement of device, and base on theory of fluid mechanics and calculates the vibratory force on sheet nickel. By analysis, under the current hoisting height, the device can effectively guarantee shaking off the sponge copper on the surface of the sheet nickel. The electrolyte flushing of sponge copper removal effect is not obvious.

To verify the resistance to moisture damage of warm mix rubber asphalt mixture, the splitting strength test of warm mix rubber asphalt mixture (WMRAC-13) was conducted under different immersion time and immersion temperature. Test results show that freeze-thaw splitting strength of warm mix rubber asphalt mixture meets the requirement of moisture stability. The immersion splitting strengths in 60°C and 4°C decline with the extension of immersion time. The immersion splitting strengths in 60°C decline faster than those in 4°C. The best fitting function of immersion splitting strengths with immersion time obeys second-order polynomial and power function respectively, and their correlations are the best. The inflection point of attenuation curves is 3th day and 20th day respectively.

The effect of nickel contents and milling parameters on the preparation procession of TiB2-Al2O3 composite powders during the mechanical alloying (MA) was studied in this paper. Milling parameters have certain influence on the phase transformation of Ni-Al-TiO2-B2O3 system during mechanical processing. With the same milling parameters, the proper content of Ni can promote the reaction route and influence the microtopography of the products.

Mechanical soil aeration is an easy, effective, and low-cost soil remediation technology; in particular, it is suitable for large sites contaminated by volatile chlorinated hydrocarbons (VCHs). Mechanical soil aeration encourages the volatilization of soil contaminants, but soil moisture, which reduces the amount of open pores, may hinder this process. The present study examined the remediation of silty soil containing 1,2-dichloroethane (1,2-DCA), chloroform (TCM), trichloroethylene (TCE), and tetrachloroethylene (PCE) using mechanical soil aeration and evaluated the influence of soil water content on the efficiency of the process. For artificially contaminated soil, the following conclusions were reached: (i) moisture undermines the volatilization of contaminants. When the soil water content increased from 5% to 20%, the residual concentrations of 1,2-DCA, TCM, TCE, and PCE in the soil increased from 0.08, 0.10, 0.09, and 0.48 mg/kg to 1.43, 0.81, 1.16, and 1.43 mg/kg, respectively. The effective diffusion coefficients also decreased from 1.88×10-2, 1.43×10-2, 1.88×10-2, and 1.30×10-2 cm2/s to 1.71×10-6, 1.30×10-6, 1.71×10-6, and 1.18×10-6 cm2/s, respectively. (ii) Residual contaminants are related to the octanol-water partition coefficient. The soil-water distribution coefficient of PCE was highest among the hydrocarbons (3.72), and the residual contaminants were mainly adsorbed on soil particles. The soil-water distribution coefficient of DCA was lowest (0.42), and the residual contaminants were mainly dissolved in the soil water.

Granulated blast furnace slag (GBFS) is a by-product of ironmaking and widely used in the cement and concrete. GBFS samples with different ratio of SiO2/Al2O3 were prepared under the laboratory conditions and ground by the agate ball mill at different times. Then they were characterized by laser particle size analysis (LPSA), scanning electron microscopy (SEM), Bertrand surface method and mechanical testing. It was found that the activity index of GBFS clearly increased with the decrease of the GBFS particle size. In the case of the average particle size about 32μm, the activity indices were irregular with the increase of SiO2/Al2O3 ratio, whereas for the average particle size about 11μm, the activity indices decreased with the increase of SiO2/Al2O3 ratio.

A large number of harmonic is mainly produced by with the discrete variable frequency soft starter. The harmonic during the motor soft starting is characterized by the high energy consumption and signal interference. Therefore, harmonic analyzing and filtering of motor discrete variable frequency soft starter is presented in this paper to achieve low energy consumption and ensure the motor soft starting stably. The following works have been done in the study: introduce the reason of harmonics appearance, analyze the harmonic, and present the filtering approach. The motor soft starter developed with this filtering approach has been successfully applied to filter out harmonic and to improve the starting performance when the motors draw the heavy-loads. It saves energy, stabilize the voltage of the power supply network.

Palygorskite/polyacrylamide (PAM) composited thickeners were prepared via in-situ polymerization. To optimize the preparation, the dependence of the viscosity, rheological properties and electrolyte resistance of the composited thickeners on the initiator concentrations, sodium hydroxide concentrations and palygorskite contents was investigated. By measuring their dynamic rheological properties, thickening mechanism of composited thickeners was explored. The composited thickeners showed excellent electrolyte resistance which represented good synergistic effect of inorganic/organic composited thickener.

Green development is the inevitable choice on sustainable development of Shaanxi province in coal mining area. First, the environment capacity of coal mining area is defined from the point of view of comprehensive environmental capacity, which expounds the scientific connotation in the particularity of the coal mining area and coal industry. On this basis, three the key affecting factors of carrying capacity of environment in coal mining area are selected, which are mining subsidence, damaged shallow groundwater, and industrial "three wastes" pollution. Second, from the point of he comprehensive environmental capacity, the measurement framework of green development degree in coal mining area is built. And it takes the key affecting factors as the subsystem. On this basis, the measurement index system of green development degree in coal mining area is established. And it has 9 first grade indexes, which are ratio of rock and mining, form of surface subsidence, buried depth of ecological groundwater, space relationship of diversion fissure zone and key to aquifer, the capacity of regional atmospheric environment, the capacity of regional water environment, waste emissions, vegetation coverage, soil erosion modulus. At last, this paper is using the AHP method and entropy method to establish the measure indication system of green development degree on coal mine area in Northern Shaanxi.

Width and height ratio is a characteristic geometry feature of wind turbine foundations. This study establishes the relationship between security of wind turbine foundations and their width and height ratios. There are a number of works on checking wind turbines, however, limited works about how the width and height ratio influences the structure were conducted. This paper provides fifteen models of three different shapes, five circular foundations, five hexagon foundations and five triangle foundations. Data from a wind farm in Guizhou, China, is used to calculate the main wind loads acted on wind turbine structures. Then key factors concerning with security of foundations were obtained. And they were put together so that it is easy for us to find their relationships. The results show foundations have different performance at different ratios. It’s change laws were so clear, security of foundations is improved by the increasing of width and height ratio. On the other hand, hexagon and triangle foundations were certificated suitable for general projects.

Granulated blast furnace slag (GBFS) is a by-product of manufacturing iron. Samples of GBFS with different ratio of SiO2/Al2O3 were prepared by simulating the actual process of GBFS in laboratory. This study investigated the influence of SiO2/Al2O3 content on structure and hydration activity of GBFS which were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), infrared radiation (IR) and mechanical testing. It is found that the vitreous content of each sample is above 97% and the hydration activity indexes of 7d and 28d of samples significantly decrease with the increase of SiO2/Al2O3 ratio. The IR characteristic absorption spectrum shows that the silicates mainly exist in [SiO4]-tetrahedra and the aluminum atoms are in different coordination states and the bonding strengths rise with the increase of SiO2/Al2O3 ratio.

The anticorrosion performance of Al2024 deposited ZSM-5 zeolite membranes prepared by situ hydrothermal method is analyzed. The results of polarization curve show that the corrosion position of Al2024 deposited zeolite membranes was higher than blank samples and the samples position at 10 h was highest. The impandance rings of samples at 10 h was biggest and the corrosion charact was uniform corrosion different from pit corrosion of Al2024 without zeolite membranes.

HPLC (High Performance Liquid Chromatography) method for danofloxacin(DAN), enrofloxacin(ENR), sarafloxacin(SAR) and difloxacin(DIF) residues in freshwater fish was developed. The fish sample was extracted with methanol-water-acetic acid(2/8/0.01, V/V/V), performed on a C18 solid-phase extraction column. With methanol+malonic acid-magnesium chloride aqueous solution as mobile phase, gradient elution at 30°C, inject volume was 20μL. The wavelength of UV detector was 280 nm. The linear rang of four drugs was 0.1~10μg/mL. In the level of 0.5μg/kg and 4.0μg/kg, the average recovery of the four kinds of drugs was 79.81%~92.03% , the RSD was 1.03%~4.07%. The limit of DAN, ENR, SAR, and DIF was 0.1μg/kg, 0.1μg/kg, 0.05μg/kg, and 0.05μg/kg individual. This method was employed to analyze freshwater fishes, such as catfish, chub and carp, because of its simplicity and high efficiency.

In order to prepare carboxyl-terminated hyperbranched polyester (HBP-COOH), succinic anhydride was used to modify hydroxyl-terminated hyperbranched polyester (HBP-OH), and the influences of the solvents, catalysts and time on the product’s structure were investigated. When THF is used as the solvent, sodium acetate as the catalyst, the molar ratio of succinic anhydride and hydroxyl groups is 3:1, and the reaction time is 6 h at 65°C, the modification extent of the hydroxyl groups is about 99% with about 95% yield. HBP-COOH has much lower glass transition temperature than that of HBP-OH due to its long and flexible end-groups.

Poly (trimethylene terephthalate)/acrylonitrile-styrene-acrylic copolymer blends were prepared and their morphology, thermal aging and mechanical properties were investigated by using the polarized optical microscopy, universal material testing machine and color-difference meter, repectively. The results suggest that ASA and PTT are partially miscible in the blends, and when TPEE content is 50%, a bi-continuous phases form in the blend. The PTT’s spherulites in the blends become smaller and even microcrystallites with increasing ASA content. ASA component has good effect on toughen PTT by increasing blends’ impact strength but depresses the tensile strength of the blends. ASA has no influence on the thermal aging properties of PTT, and PTT/ASA blend has better thermal aging resistance than that of PTT/ABS blend.

With assistance of copper ions diamond-like carbon (DLC) films were deposited on Cu substrate by liquid-phase electrochemical deposition method from a mixture of ethanol as carbon source and deionized water containing K2CO3 as electrolytic. The electrode process was analyzed and the morphology, composition and structure of the films were studied by scanning electron microscopy (SEM) and Raman spectroscopy respectively. The results show that: on the condition of 40V and 7mm between the electrodes DLC films were deposited by adding K2CO3. With assistance of copper ions the electrode reaction was promoted, the deposition rate was improved. SEM shows that the DLC film deposited with copper ions assisting is comprised of uniformly distributed particles. And the Raman spectrum shows that the G band position moves to lower wavenumber and the ratio ID/IG decreases which indicate that there is more sp3 content in the film.

During cold preservation, the pH and moisture of beef decreased slowly. Changes in ash and protein content had no obvious rules, but the data analysis results showed that the effect of drugs on these indexes was significant. Ca, Fe content decreased, Zn content increased, TBARS values were significantly higher than those in the blank , and violent fluctuation. SAR and DIF had obvious bacteriostasis effect. Cold preservation had no palpable effect on fluoroquinolones residues.

The solubility of hexachlorobenzene in different solvents (hexachlorobutadiene, tetrachloroprene, benzene, toluene and chloroform) at different temperatures was measured by the dynamic laser method and equilibrium method. The measured solubility data were correlated with Apelblat empirical equation. The results show that the equation is suitable for description of the solubility data of hexachlorobenzene in the above solvents.

Greenhouse temperature control is a key factor which affects crop growth, and the traditional way of temperature regulation already cannot satisfy the requirements of modern greenhouse: high precision, rapid acquisition and response. The 32-bit EasyARM1138 single chip microcomputer is taken as the main control chip to implement multiple canopy temperature acquisition and control. AT89C52 single chip microcomputer is applied as assisted control chip to implement single greenhouse temperature control. DS18B20 digital temperature sensor is used to collect temperature information in the greenhouse. Through buttons, LCD monitor, GPRS SMS alarm module, and light alarm system with LED and buzzer sound to realize human-computer interaction. Through analyzing of the present condition of greenhouse environment, greenhouse temperature parameters are adjusted to achieve the requirements of crops growth and cultivation development to provide the most suitable temperature environment for crop growth, and increase crop yield and quality.

The B2O3-SiO2binary system has been thermodynamically reassessed with CALPHAD approach. The substitutional solution model is adopted for liquid. A set of self-consistent parameters capable of reproducing the corresponding experimental phase diagram data and subliquidus immiscibility data has been obtained.

Gushing water in deep well and roadway has become a crucial technique problem which threatens mining safety. Taking advantage of transient electromagnetic, high-density electrical method and a combination of geological analysis, drilling testing analysis, an analytical method for gushing source and path was proposed, and types of gushing water were sorted in light of the cause of formation and governing strategies. Each gushing characters were systematically studied, thus forming the corresponding governing key techniques. Governing methods and main qualification for surrounding rock safety were proposed, with a careful consideration of the surrounding rock safety during grouting. The achievements are widely used in Guotun coal mine in Juye coal field with success, which offers a reference for similar engineering.

Using a laser monitoring observation technique, the solubility of fructose diphosphate sodium in binary solvent of ethanol + water mixtures was experimentally measured in the temperature ranging from 298.15 K to 333.15 K at atmospheric pressure. The solubility of fructose diphosphate sodium increased with an increase of temperature and quality percentage of water. Experimental solubility data were correlated with semi-empirical models; and the calculated solubilities of fructose diphosphate sodium show good agreement with the experimental values.

This article introduces the principle and equipment of FDR for detecting the water content of subgrade. It also demonstrates the details of the 5TM sensor’s installation. By comparing the water content between excavation subgrade and fill subgrade, it illustrates that subgrade form has a significant effect to water content of subgrade, which also provides powerful basis for regular maintenance of subgrade and ensures the normal operation of the highway.

The SiO2-ZrO2binary system has been thermodynamically assessed with CALPHAD approach. The substitutional solution model is adopted for liquid. A set of self-consistent parameters capable of reproducing the corresponding experimental phase diagram data and liquidus immiscibility data has been obtained.

While Wheat cultivation in Henan Institute of Education experimental field as tested materials, and C17 as the basic culture medium, we researched the influence of KT in different concentration on wheat anther dedifferentiation. The results show that added to 0.25mg / L of KT in the medium, wheat anther dedifferentiation was the best, and it had the best stability.

Microphases and triangle phase diagrams of cyclic ABCB tetrablock copolymer melts have been investigated by a combinatorial screening algorithm based on self-consistent field theory (SCFT) in two-dimensional space. Eight main stable ordered morphologies have been observed in the intermediate-segregation regime. SCFT simulation experiments reveal that the compositions of block chain in the cyclic polymer are comparable, the cyclic architecture of polymer chain has a strong topological constraint on the geometry of microphases. The morphologies and phase diagrams are helpful to control and design the suitable ordered microstructure of cyclic copolymer systems.

A large number of inductive loads need the reactive power, and the amount of the reactive power compensation is different in a state of work. The traditional static reactive power compensator is difficult to meet the needs of the reactive power compensation for the composite load reactive. Therefore, a dynamic reactive power compensation method of the composite power load is proposed in this paper. The following works have been done in the study: principle of dynamic reactive power compensation control method, topological structure of dynamic reactive power compensation device, and implementation of the dynamic reactive power compensation control method.

The austenite steel after rolling was radiated by the alternating magnetism, and the effects that alternating magnetic on the austenite transition was studied. The result shows that the alternating magnetism promotes the austenitic grain growth of low carbon steel. If the magnetic field intensity is increased, it could provide better performance of raw materials to cold rolling processing.

On the basis of successfully preparing nanozirconia coating via reasonable spraying technical parameters, the cross section and surface morphology of coating were determined by scan electron microscopy (SEM), and the ceramic particle sizes of coating were determined by transmission electron microscopy (TEM). Experimental results indicate that plasma sprayed zirconia coating possesses typical layer structure of thermal spray coating, in which columnar grains pile up together. Meanwhile, the non-molten nanopowders coexist with the layer structure. In addition, the equiaxial grains exist in the zirconia coating according to TEM, but the grain size is not uniform.

The ore using in this paper was obtained from Hunan Province, China, which contains fluorite (15.65%), barite (48.42%), quartz (30.56%), sphalerite (0.57%), galena (0.54%) and other minerals. After fluorite-barite mixed flotation, fluorite-barite separation flotation, and anti-flotation of lead and zinc minerals, the fluorite concentrate with 97.35% CaF2 and barite concentrate with 95.49% BaSO4 was gotten. The recovery of the fluorite concentrate was 81.85% and the recovery, specific gravity, whiteness of the barite concentrate was 95.00%, 4.34g/cm3, 90.65%, respectively. This symbiotic ore can be comprehensive utilized by this beneficiation procedure.

Graded broken stone has good road performance and it gradually began to adopt in strengthening the domestic old road or the new road design, because it is the repose of aggregate materials ,can effectively prevent the occurrence of reflection cracking and has good bearing capacity. Graded broken stone material has obvious stress dependent characteristics and the stress strain curve is nonlinear variation. Stress state and its place in the structure of pavement layer, layer thickness and modulus of the structure are directly related. Therefore, the paper has analyzed the thickness of each layer in the design of reinforcement structure impacting on the grading macadam stress state.

Using self―made model device, researchers studied the characteristics of foundation settlement of sandy soil and pile foundation load―bearing in sandy soil. Through weight loading, researchers analyzed the phenomenon of foundation settlement. Then, researchers embedded friction piles in sand, so as to analyzed pile foundation bearing capacity. The methods and results of the research can provide guidance for teaching of Soil mechanics and foundation engineering.

The accurate diagnose of the timing of regeneration is the key factor of solving the problem that the filter body is damaged and the process of regeneration is uncomplete. The timing of regeneration judged by the exhaust back pressure is a type of widely accepted control method, the essence of which means to estimate whether the quantity of particle in the filter can fulfil the demand of regeneration or not. In the process of practical application, this kind of method is influenced by the engine conditions, therefore, we must monitor the engine at any moment by speed and load of signal acquisition.In this article,it summarizes two dimensional pulse spectrum" exhaust flow--pressure drop” through universal characteristics test. Meanwhile it conducts the temperature correction in order to simplify the complexity of the judge-ment of regeneration opportunity.

A nonlinear controller is presented for a digital hydraulic cylinder against disturbance. We first establish the nonlinear model of digital hydraulic cylinder position control system. Then a Lyapunov function and a nonlinear controller are presented. The controller designing problem is translated into the problem of solving a linear matrix inequality. The experiment results show that the controller proposed by this paper has much better performance than traditional one.

Transmission spectrum and reflectance spectrum have long been used to characterize gap semiconductor. Transmission spectrum can be measured very directly, but the influence of substrate absorption is often unavoidable. However, when using the reflectance spectrum measurement, the absorption of thin film, substrate absorption, and coherent interference will make the reflectance spectrum much more complicated. In this paper, Considering the absorption of thin film, substrate absorption, and coherent interference, we use the envelope curves algorithm to achieve the calculation formula of refractive index deduced from the reflectance spectrum. Through the analysis of the reflectance spectrum of Ga2O3film, we achieved thickness of the film, refractive index, extinction and absorption coefficient and dispersion constant.

In the article, a digital machining environment of CNC lathe is established. On the basis of the idea of Constructive Solid Geometry method, the system consists of the blank display model, the tool and fixture model, CNC machining program editing model and machining simulation model. By making use of VC++ and OpenGL graphics technology the program is done for machine tool motion simulation and cutting simulation. It is an effective accessory tool in the application of CNC lathe to digital production.

The prevention and control of pollution is an important technical link in haploid breeding of wheat. From the pollution types,causes and prevention methods in the process of wheat anther culture to analyze how to reduce pollution problems appeared in the tissue culture,so as to achieve the purpose of decreasing the cost of wheat breeding,and improving the efficiency of breeding purposes.

Significant geological factor of coal occurrence is layered structure of coal measures overburden rock, and bedrock sand-shale ratio is a key element of coal measures overburden rock layered structure. On the background of geological occurrence conditions of 2-2 coal in Yushen coal mining area, the sandstone layer, sandstone average thickness and sand-shale ratio are taken as variables to build the 18 different types of layered structure models. On this basis, basic law of coal measures bedrock sand-shale ratios which is a key characteristic of layered structure impacting mining subsidence is mainly studied by using numerical simulation method. The results show that: firstly, in spite of any condition of sandstone layer coefficient subsidence coefficient always decrease with the increase of sand-shale ratios. However, the effect of sand-shale ratios on subsidence coefficient continuously decreased with the increasing of sandstone layer coefficient. Secondly, when the sandstone layer coefficient is less than 70%, the different sand-shale ratios have significant influence on the subsidence coefficient, and when the sandstone layer coefficient is more than 90%, subsidence coefficients corresponding to different sand-shale ratios show obvious convergence characteristics. The gap between each other is only 1%~2%. Thirdly, taking the subsidence coefficient corresponding to the sand-shale ratio is 6:4 as reference, the curves about the rate of decrease in subsidence coefficient is set up when the sand-shale ratio is 7:3 or 8:2, and the fitting equations are presented on the basis of Log3P1 mathematical model.

Based on the situation that universal mill’s roll rings appeared broken roller accident in actual production, the paper put the horizontal roll ring of universal mill as the research subjects. The thermal structure coupling field of horizontal roll ring reaches a dynamic equilibrium and the stress distribution of horizontal roller ring and finds the most dangerous parts of the roller ring is rolling groove. This study provides a solid foundation for further research of the roller ring strength, deformation and fatigue life.