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In this paper, the Mg-Al hydrotalcite-like compound (Mg-Al-HTLC) was synthesized by hydrothermal method at 373K. Structure and morphology of Mg-Al-HTLC was obtained with X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infra-red spectroscopy(FTIR). A series of polar and non-polar molecules were used for probes, surface properties of Mg-Al-HTLC was studied by inverse gas chromatography (IGC) at 353K, 363K, 373K, 383K respectively. The retention volume was utilized for evaluating the free energy of adsorption (-ΔGSP), the dispersive component of the surface energy(γsD), as well as the enthalpy and entropic component(ΔHSP, -ΔSSP). XRD results reveal that the Mg-Al-HTLC has high crystallinity and perfect layered structure. The results of IGC show that Mg-Al-HTLC would adsorb straight-chain alkanes spontaneously, and the values of γsDwere similar at all temperature. It reveals Mg-Al-HTLC is a material with particular characteristics of both acid and base. This study illustrates that, as a method to evaluate the surface properties of material , IGC method is dependable and significant.

Textured self-lubricating tools were fabricated by fiber laser machining. Dry milling of titanium alloys was carried out with these textured tools and conventional one for comparison. The cutting forces, cutting temperature, surface roughness of processed workpiece and tool flank wear were measured. Results show that the textured tools can reduce the cutting forces, cutting temperature and surface roughness of workpiece, as a result, present superior wear-resistance compared to the untextured tool.

The BaFe12O19 nanoparticles was prepared by sol-gel method in different temperature (750°C,850°Cand 950°C), and then BaFe12O19/polyaniline nanocomposites was synthesized by in situ polymerization. The XRD, FTIR spectra, SEM and vector network analyzer were used to analyze the "" chemical component, morphology and microwave absorption property of the nanocomposites. The result show that BaFe12O19 can be generated at 750°C without any impurity ,and its size increased with increase of calcination temperature.BaFe12O19 nanoparticle was coated with polyaniline partially, and we can get it have interaction with polyaniline through FTIR spectra. While the ferrite calcined at 850°C,the thickness of the absorbing material is 4.5mm,the nanocomposites have the largest reflection loss of-17.6 dB at 6 GHz,and its reflection loss values less than−10 dB in the range of 5-7.4GHz.

The purpose of this article is to synthesize the thiol-and carboxyl-bifunctionalized mesoporous silica nanoparticles (CMS-SH-COOH). CMS-SH-COOH was successfully synthesized by co-condensation and post-grafting methods. Moreover, the particle size and structural properties of CMS-SH-COOH were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FT-IR). The obtained results indicated that the CMS-SH-COOH presented a uniform spherical shape with a wormhole arrangement of the mesopores and a relatively narrow paticle distribition. Therefore, the CMS-SH-COOH might be a great potential carrier for the drug delivery system in the future.

Ceramsite cellular concrete (CCC for short) is a kind of lightweight aggregate concrete. In this paper, the selection of materials and design of mix proportion have been discussed, and basic property tests has been done. The compressive strength was proved up to the National Standards of P. R. GB50003-2001(code for design of masonry structures), furthermore, elastic modulus and Poisson's ratio were also introduced. Questions remain regarding the quality control of the product, and further work is needed to resolve this contradiction.

Graphene oxide (GO) was prepared by modified Hummer’s method, and reduced by solvothermal method using ethanol as the solvent and modified diethylene triamine (amine curing agent 593) as reducing agent and modifier. The effect of reduction time and temperature on the structure and conductive property of reduced graphene oxide (593-rGO) was investigated by SEM, FT-IR and XRD. The results show that the graphene modified by 593 is obviously improved in dispersibility and sedimentation stability in dichloromethane, as well as in conductivity. The optimal reduction processing is that the mass ratio of GO to 593 is 2:1, the reduction time and temperature is 6 h and 160°C, respectively.

Different cooling process, annealing temperature and addition of B2O3were experimented on the CaO-MgO-SiO2-Al2O3-Cr2O3-Fe2O3slag system with an aim to investigate the chromium precipitation behaviour. The solidified slags were characterized by XRD, SEM, EDX and EPMA. It was shown that, under melt-quenching process, chromium was immobilized in amorphous structure in the slag with basicity lower than 1.0 and Cr2O3content less than 4.0 wt%. It was also found that addition of B2O3and higher annealing temperature would be helpful for the precipitation of chromium into spinel solid solution in slag with basicity of 1.5.

In the paper, according to crushing and attrition of material on mixer blade, the mechanical model of material on blade is established. According to nonlinear vibration and the basic theory of rotor dynamics, Mechanical model of vibration system and differential equations of motion are established. This paper has adopted the arithmetic of fourth-order Runge-Kutta, analyzing wave forms graph, chart of axis track, phase plane plot of system movement. Analysis results show that mixer system appears chaotic motion under some certain design parameters. This state of motion on mixers can better destroy cement coagulation group, increasing the number of effective collision of concrete particle, which can effectively improve the microscopic homogeneity of concrete and improve efficiency of concrete mixing.

After representing the situation of the spacecraft assembly and the concept of Model Based Definition (MBD), the paper describes the method and principle of Assembly Digital Mock-up (ADMU), which achieved the transition of Engineering Bill of Material (EBOM) to Process Bill of Material (PBOM). With reconstructing EBOM and fulfilling structured Product Attribute, the paper gains the ADMU, which is the data source of spacecraft assembly process design based on 3D models.

In order to study the effects of the supporting beams with different forms of section on the aerodynamic characteristics of car models. Model supporting beams with three different forms of section were designed based on standard MIRA model. The commercial CFD software - Ansys Fluent was used to simulate the three-dimensional flow field around the standard MIRA model installed with three different kinds of supporting beams. With comparisons between the drag coefficients, pressure distributions and velocity distributions around the wheels with the different supporting beams, the reasons for the differences in aerodynamics are analyzed and advices were given for helping choosing the supporting beam with minimal disturbance to reduce the correction error.

With the construction of power grid, operation safety risk in the power supply enterprises is to increase ceaselessly. Corporate managers need to solve the problem how to carry out the operations safety risk management. This paper analyses production operation risk management status of power supply enterprises, describes the content and process of production operation risk management, and then expounds how to achieve information management of production operation risk by establishing production operation risk management and control system of information management. Finally, construction ideas of the system is proposed in the terms of design principles, deployment way and functional design.

Fine Chemicals is an important direction and inevitable trend of development of China's petrochemical industry. In order to occupy the commanding heights of industry development strategy, many domestic chemical companies enhance their ability to resist risks, fine chemical products to take extended strategy. However, due to the fine chemicals own characteristics, while enterprises is in product extension, they are often faced with complex decision problems. Based on all of those, multi-product programs projects preferred aand the main product of the extension when siting evaluation are research.

With the development of offshore oil and gas field enters into deep water constantly, subsea production system has become the main development mode in deep water development. Subsea Inline manifold (ILM) is common facilities in subsea production system and is used to gather oil and gas from the side subsea wells. Two subsea ILMs has been adopted in Panyu 35-1/35-2 Gas field with water depth range from 194 to 338 m in South China Sea. System integration test (SIT) is very important for the subsea production facilities. This paper states the flow chart, master equipment, purpose and precautions for each test of ILM SIT, which collects great technology for the development of subsea production system.

The control core of this design is MCU AT89C51,with the sensor MPX4115,it can complete the detection of weighting signal.Use the ADC0832 chip to achieve signal conversion, the input use a square 4*4 keyboard,the output display use the LCD LM4229.Use C Language Programing to achieve the modular design of software,use proteus simulation system to achieve the measure of weight of nine kinds of goods,The weighing range from 0.546Kg to 4.980Kg;Its resolution is 0.001Kg;This system has the function of calculating total price,storing single price,alarming when the goods overweights. Key words: AT89C51MCU;A/D exchange;Sensor

In the paper, we establish a 3D mathematical model of granulation chamber based on experimental data and “two phase flow” theory, simulate the process of dry granulation and study the temperature field of granulation chamber. The analysis result shows that granulation time must be controlled in 6 minutes, otherwise the plasticity of particles will be damaged and the final effect of granulation will be influenced.

PbTe nanocrystals (NCs) have been synthesized by a novel method at low temperature. Pb acetate being solved in glycerol and Te in TOP solution were used as the precursors for the preparation of PbTe nanocrystals. The as-prepared products were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), UVvis absorption, Fourier transform infrared spectroscopy (FTIR). These data, together with analysis of the absorption spectra, allowed us to observe the size dependence of the peaks in the absorption spectrum. The size-dependent optical spectra of the PbTe nanocrystals exhibits wide tunable band gap energies varying from UV visible range to near IR region, which corresponds to a huge blue shift of 3.0 eV in comparison to the bulk counterpart. Keywords: 1. PbTe nanocrystals, 2. optical properties, 3. wide tunable band gap, 4. microstructure

The blade is one of the key part of aero engine because its shape precision and surface quality significantly influence the performance, efficiency and reliability of the engine. The blade surface is generally obtained by precision finishing process, which is a repeated work of profile error measurement, profile error calculation and error correction manufacturing. For profile error calculation, the matching of measurement points and ideal blade surface must be firstly performed. However there is few detailed work reported on matching algorithm. In this paper, a new matching algorithm for profile error calculation was proposed. Firstly, the coarse matching method based on characteristics of blade section curves between measurement points and its corresponding ideal section curve was studied. Then the Sigular Value Decomposition (SVD)-Iterative Closest Point (ICP) precision matching method was adopted to improve the matching precision. After that, the weight calculation method was applied to balance the profile errors among different section curves. Simulation work was performed to validate the proposed matching algorithm. Results shows that micrometer-order matching accuracy of the blade section curves could be obtained through the above-mentioned three matching steps.

The effect of carbide orientation on the dry sliding wear behaviour of high chromium cast iron was studied by pin-on-disc type wear tests at room temperature. The carbide anisotropy was achieved by thermomechanical treatments at temperatures of 950 and 1150 °C. By cladding with low carbon steel, the brittle high chromium cast iron was hot compressed severely with crack free. The thermomechanical treatments not only change the carbide orientation, but also increase the volume fraction of carbides. Due to the long axis of carbide rods is parallel to the wear surface, the high chromium cast iron treated at 1150 °C has a superior wear resistance than the as-cast one, in which the long axis of carbides is perpendicular to the wear surface. For the high chromium cast iron treated at 950 °C, high volume fraction of carbide pits accelerates the wear rate significantly even though it has a similar carbide orientation as the sample treated at 1150 °C. The observations on wear tracks reveal that the ferrous matrix can be protected better from abrasion when the high chromium cast iron was treated at 1150 °C.

The Xiongcun district is located along the south margin of the Gangdese porphyry copper belt, approximately 53 km west of the Xigaze. No.III deposit is a newly discovered porphyry copper-gold deposit in the Xiongcun district. This paper first reports geological characteristics and exploration potential of No.III deposit. No.III deposit is hosted by Early Jurassic hornblende quartz diorite porphyry. Pervasive alteration is dominated by a well-mineralized potassic alteration. Major ore-bearing vein types include quartz-sulfide and chlorite-sulfide veins. Drilling holes and geochemical anomaly indicated the No.III deposit has excellent potential for exploration.

The combustion stability of pulverized coal is very essential for utility boilers. That is the key issue to keep the operation of the whole power-generation unit in a safe state. The amount of volatile matter is used to anticipate the combustion state of pulverized coal. As a widely accepted concept, higher volatile matter content would result in more stable combustion state. But in some cases, the coal with high volatile matter content led to poor combustion states, even resulted in the flameout of the burner. More method is needed to judge the coal and to predict the combustion stability. With research on the approximate analysis of the coal composition, the heat value of volatile matter was calculated. Such heat value varies obviously for different kinds of coal. The ratio of the heat value of volatile matter to the heat value of fixed carbon is supposed to describe the combustion stability of pulverized coal. The application of the method judges the coal better than using the amount of volatile matter alone.

In order to restrict over-voltage and compensate line charging power, there is a need to install high compensation shunt reactors in ultra-high voltage AC transmission lines. Due to the saturation characteristic of core limb during the working progress in the magnetically controlled shunt reactor (MCSR), the current higher harmonics exist in the high voltage winding. Based on finite element, the method which analyzes the controlling characteristic of high voltage winding with 500kV MCSR demonstration project in the Jiangling converter station is presented in this paper. The magnitude and frequency of harmonic current in the high voltage winding current is derived by this method. Through the comparison with the measured results of 500kV MCSR, the validity of method is proved.

Based on POC set theory and SOC unit, a 1T3R parallel stable platform is proposed. The Single cylinder force analysis is studied. Then uses Newton-Euler method, gives full consideration to these various factors: without neglecting the ball screw rotation, friction between the spherical joint, the mass and the moment of inertia of electric cylinders, based above the dynamic theoretical Analysis of the stable platform is researched. The paper makes the guide sense for the follow-up research and the application of the 1T3R mechanism.

The thermogravimetry - differential thermal analysis (TG-DTA) and theoretical analysis method of Coats-Redfern were employed to study the pyrolysis process and kinetics characteristics of mixture containing lime-mediated sewage sludge and gas ash, then sintering cup test the different proportion of mixture ball. It was found that the pyrolysis process of mixture from indoor temperature 1200°Ccould divided into 4 the weight loss stages, which brings a large number of heat and CaO, Fe2O3. Base on the results of Coats-Redfem integration method, the pyrolysis process of mixture under air atmosphere was belongs to two-class reaction. Sintering cup test show that lime-mediated sewage sludge and gas ash replacing part of the sintering ingredients is feasible.

The classical mean shift (MS) algorithm is the best color-based method for object tracking. However, in the real environment it presents some limitations, especially under the presence of noise, objects with partial and full occlusions in complex environments. In order to deal with these problems, this paper proposes a reliable object tracking algorithm using corrected background-weighted histogram (CBWH) and the Kalman filter (KF) based on the MS method. The experimental results show that the proposed method is superior to the traditional MS tracking in the following aspects: 1) it provides consistent object tracking throughout the video; 2) it is not influenced by the objects with partial and full occlusions; 3) it is less prone to the background clutter.

objective: study the association between TNF gene and essential hypertension (EH) in Chinese minority Zhuang population. Method: select 170 normal as control group and 246 patients with EH as an object of study, use polymerase chain reaction - restriction fragment length polymorphism method to analyze polymorphic loci in the promoter region of TNF-α gene-308G / A allele, and genotype frequency distribution characteristics were analyzed, and the relationship between genetic susceptibility polymorphisms and EH was given.

The hot compressive deformation behavior of SWRCH 35K was studied with uniaxial hot compression simulation tests at 923 ~ 1223 K and strain rate of 0.01 ~ 20 /s. The results show that the hot compressive deformation activation energy was 408 kJ/mol and the rang of deformation stored energy was 10 ~ 50 J/mol. The quadratic fitting expression between deformation stored energy and Zener-Hollomon parameter (Z) was established and the deformation stored energy was considered to increased with increasing Z or with lower deformation temperature and increasing deformation rate.

Taking factors such as astronomy, atmosphere, microgeography and local landscape that comprehensively affect solar radiation into account, we established a direct solar radiation (DSR) model on the accidented topography. Dynamics of DSR on accidented topography in Henan province were also statistically analyzed. Modeling results showed that highest DSR in Henan occurred between May and July, while lowest DSR occurred between December and February of the next year, and the multi-annual mean DSR in Henan province was 2127.7MJ/ m2. Impacts of local landscape on DSR on accidented topography in Henan province differs in different seasons. In winter half year, during which solar altitude angle is relatively low, this impact is more significant.

The conical surface sealing performance of a pipe connection fit (PCF) has been studied by means of an equivalent mechanical model and the contact finite element analysis (FEA). By building an equivalent mechanical model, we studied the basic mechanical relations between the jointing parts, proposed a sealing mechanism, and identified a basic pretension-relaxation-leakage mode occurring in the sealing process of a conical surface PCF. Then we simulated the contact states of the PCF sealing surface using a multi-body elastic contact finite element method (FEM). In addition, the characteristics of the pretension-relaxation-leakage mode were further discussed in terms of the contact forces as well as the contact areas on the sealing surface. These results revealed some fundamental characteristics inherent in the sealing process of conical surface of PCFs, and demonstrated the potentials of the contact FEA in studying PCF sealing performance.

In this paper, through the study of the marine conditions of structural facilities applications, in order to reduce the corrosion of marine structural facilities, Asked the neural network algorithm combined genetic algorithm to determine the components of the coating to the development of composite scales heavy anti-corrosion coatings, it has interpenetrating polymer network structure (IPN). Experimental results show that the composite scales heavy anti-paint adhesion, excellent corrosion protection, easy to use marine engineering, field operating conditions used, and its sources of raw materials widely,modulation process is simple, easy to mass production and application, can be reduced to some extent marine the cost of structural facilities for anti-corrosion.

An oligotrophic culture of acidophiles (Alicyclobacillus) isolated from Dexin acid mine drainage was evaluated for its synergistic effect in chalcopyrite bioleaching. Bioleaching of chalcopyrite with and without theAlicyclobacillusculture was investigated at different temperatures (33°C, 45 °C and 65 °C) and a culture-independent approach based on 16S rRNA gene clone library was used to analyze changes in the microbial community change during the bioleaching process. For 33oC leaching tests, only the bacterial community was analyzed, but for the other two temperatures, both the bacterial community and archaea communities were analyzed. Results showed that at high leaching temperature (65°C),Alicyclobacillusculture could increase copper leaching recovery from 57.83% to 60.7%. While at relative low temperature (45°C and 33°C), addingAlicyclobacillusculture inhibited copper bioleaching, copper leaching recovery decreased from 36.10% to 31.52% and from 34.02% to 21.97% respectively at 45°C and 33°C. Clone libraries analysis showed thatAlicyclobacillushelps the growth of genusSulfobacillusat 45 °C while inhibiting the growth of genusLeptospillumat both 33°C and 45 °C. Furthermore, when addingAlicyclobacillusgrowth ofFerroplasmawas limited andAcidoplasmawas facilitated at 45°C. At 60°C, addingAlicyclobacillusculture facilitated the growth of genusMetallosphaerawhile limiting the growth ofLeptospillumandFerroplasma. The results showed potential application ofAlicyclobacillusin high temperature chalcopyrite bioleaching and bioremediation of acid mine drainage.

The effect of solvent extractants, such as M5774, Cyanex 272, P204, P507 and N235, on the activity and community structure of acidophilic microorganisms were tested. Cobalt extractant Cyanex 272 did not show much inhibition effect on the growth of acidophiles, while iron extractant N235 had great inhibition effect. When the culture solution contacted with iron extractant P204, nickel extractant P507 and copper extractant M5774, the inhibition effect increased gradually. 16S rRNA gene clone library were used to analyze the initial and extractant contacted final microbial community structure. The initial inoculation microbial populations were mainly composed by Leptospirillum ferriphilum and Acidithiobacillus ferrooxidans. After cultivated in solution containing extractant M5774, Cyanex 272, P204 and P507, the number of the two species decreased, while heterophilic Acidiphilium cryptum became the dominant population. When cultured by M5774 and Cyanex 272, the proportion of Acidithiobacillus ferrooxidans was higher than Leptospirillum ferriphilum, while when cultivated by P204 and P507, the number of Leptospirillum ferriphilum was higher.

In the bioleaching process, many factors in ore, water and sediments are important contributors as driving forces to improve leaching efficiency. In this study, FeSO4·7H2O and S0as energy substrates were added to an oxide-rich, low-grade copper ore to explore the influence of biological and environmental factors on leaching efficiency. Mantel test results showed that the leaching rate was significantly correlated with biological and environmental factors with r values of 0.78 and 0.63 respectively, indicating that influence of biological factors were more significant. It cannot be ignored that environmental factors were important to construct the microbial community. Real-time quantification polymerase chain reaction (RT-qPCR) showed that the dominant and minor species wereA. caldusandA. ferrooxidans. Canonical correspondence analysis (CCA) made it clear that pH and ferrous concentration were crucial for shaping microbial community. All results are of great significant to gain the optimal leaching condition on Zambia oxide-rich, low-grade copper ore.

In order to investigate the effects of mining pollution to LongJiang River and to know the situation of LongJiang River, we collected water and sludge samples along the river and analyzed the heavy metal content of samples. Results showed that LiDeFen factory and JinHe mining released most of the heavy metals to LongJiang River two years ago, and the upstream of LongJiang River also released some metal to the river. These heavy metals were precipitated to the bottom of LongJiang River by using weak alkaline chemical precipitation technology, and water quality of LongJiang River can reach the second national environmental quality standards of surface water now. The precipitation effects were different in different remediation sites.

The purpose of this paper is to present some results for Lagrange-Fenchel dualities, via a perturbation approach and a conjugate mapping for the set-valued optimization which is under the assumption of Benson efficiency.