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Graphene was attended widely in recent years because of its excellent performance in electrical, mechanical, optical and magnetic applications. X-ray photoelectron spectroscopy (XPS) is commonly used tools for studying the chemical binding state, chemical modification, heteroatom dopants and quantitative chemical composition of graphene. In this work, XPS characterization of graphene films, obtained through reduction and then thermal treatment of graphene oxide films, was studied. The XPS of the graphene films are performed by direct testing, Ar+ etching, and direct peeling of the surface layer. The result shows that for graphene film, direct peeling is a simple and easy to use low-cost treatment, which can also be extended to XPS testing of other two-dimensional (2D) materials.

The research on molecular devices, fluorescent labels and fluorescent probes based on the interaction between biomolecular DNA and fluorescent dyes has been paid more attention at home and abroad. In this paper, the luminescence properties of the [Ru(bpy)3]Cl2 complex itself were investigated, and the luminescence properties of the [Ru(bpy)3]Cl2 complex under the interaction of the solution and the film were observed by association of the DNA complex with the [Ru(bpy)3]Cl2 complex. The results showed that [Ru(bpy)3]Cl2 emitted red light with its main emission peak wavelength was 610nm, and its fluorescence intensity was the highest when the concentration of solution substance was 10mmol/L. When doped with DNA solution in [Ru(bpy)3]Cl2 complex, a small amount of fluorescent dye [Ru(bpy)3]Cl2 can be used to achieve a higher luminous intensity At the same time, the fluorescent dye [Ru(bpy)3]Cl2 doped with DNA solution reached a higher luminous intensity in the thin-film state. This experiment provides an important experimental basis for the application of fluorescent substance [Ru(bpy)3]Cl2 in luminescent thin films.

In order to determine the weldability of a new type of low alloy high strength steel, the feasibility of the proposed welding process was examined and the welding procedure qualification of a new type of ultrahigh strength steel WELDOX 1100 was carried out through the weldability test of the welded joint, the small iron research and the highest hardness test. . The test result satisfies the specification requirements and proves that the proposed welding process plan is correct and feasible. It provides a reliable basis for the preparation of welding process documents and ensures the smooth development of the company's new products.

The hydration products, microstructure and development principle of intensity of cement-glass powder cementitious materials acted in alkali and activation effect of chemical activation on waste glass powder were investigated. The principle of intensity and effect of curing time was analyzed by changing alkali type, content of alkali, incorporation of glass powder, incorporation method of activators and other factor. The result shows that: sodium carbonate and sodium silicate can single stimulate activity of glass powder under a certain condition, the activated effect of combined admixture is superior to the effect on single-doped activator, under the action of an excitation agent, surface hydrolysis of glass powder takes place on the glass body first and the hydration products occurs, The pozzolanic reactivity of glass powder increases gradually and generated a larger amount of hydration products，which has lapped and interlocked growth between each other，and form the compact hardened matrix. In addiation, the shorting of curing time is used by activator, the result may be lead to initial curing and against in engineering construction.

Substance flow analysis (SFA) is an established method to analyze the structure and characterization of resource flows or substance flows. Lanthanum (La) is an important type of light rare earth element, which is widely used in the fields of glass, luminescence, catalyst, agriculture, etc. This paper conducts a static SFA for lanthanum in China in 2002 and 2011, including different life cycle stages, e.g., exploitation, concentration, smelting, manufacture, use and disposal. Mining utilization efficiency, smelting ratio, export rate, ratio of scrap to raw material in 2002 and 2011 were comparatively analyzed. The results indicated that the utilization efficiency of La in the production stage of rare earth concentrates increased in 2011 relative to the value in 2002 by 80%, and the utilization efficiency of La in the manufacturing stage increased by 74%. The results also showed that although the mining utilization rate was increased, the resource efficiency was still low and how to increase the resource efficiency is a significant issue for Chinese rare earth industry. On the based of the results, some advices were also proposed, which will provide useful reference information for the green development of Chinese rare earth industry.

A novel near-infrared fluorescence quenching method has been developed for the determination of hydrogen peroxide based on N-acetyl-L-cysteine-capped gold nanoparticles (NAC-AuNPs) as a fluorescence probe. The prepared gold nanoparticles with the size of about 1.91 nm exhibited strong near-infrared fluorescence emission at 693 nm with excitation wavelength at 450 nm in aqueous solution. The fluorescence intensity of NAC-AuNPs was quenched dramatically by adding hydrogen peroxide. Therefore, it could be used to detect hydrogen peroxide based on the fluorescence quenching intensity was linear with the concentration of hydrogen peroxide. Under the optimal experimental conditions, the linear range and detection limit were 1.0×10-6 –3.0×10-2 mol/L and 1.0×10-7 mol/L, respectively. The possible quenching mechanism was investigated by time-resolved fluorescence spectroscopy. The proposed method was simple, sensitive and showed good repeatability and stability.

Arsenic, antimony and bismuth in gold ores were simultaneously determined by inductively coupled plasma optical emission spectrometry (ICP-OES) with spectral lines of 188.980, 206.834 and 223.061nm as analytical line respectively, under preset instrumental parameters. The linear range of the method for arsenic, antimony and bismuth was 0~80ug/mL and the correlation coefficient was greater than 0.99995. The detection limit for arsenic, antimony and bismuth was 2.87, 1.63 and 0.84ug/g respectively. The results of this method are consistent with the national standard method, and the relative error is less than 1.5%. The relative standard deviation (RSD) of this method is better than 5.0% (n=11) with good accuracy and precision. ICP-OES can be used for simultaneous determination of multiple elements and is suitable to the analysis of large quantities of samples.

The aim of this paper is to explore material flow analysis, study the resource consumption and environmental impact of the production preparation process of typical rare earth materials. The results showed that in the beneficiation processes, producing one ton of rare earth concentrates (Rare Earth Oxide, REO50%) will also produces 27 tons of iron ore and 21 tons of tailings. The recovery of rare earths is only 16.8%. In roasting processes, roasting one ton (REO50%) of rare earth concentrates will emits 150 ~ 200Kg sulfuric acid mist, 500 ~ 600Kg sulfur dioxide, 30 ~ 40Kg fluoride, 30 ~ 50Kg smoke and1t (containing thorium) radioactive slag, and 1.2 tons of concentrated sulfuric acid should be used. The lower recoveries and large-scale of concentrated sulfuric acid used in roasting processes in rare earth industry are the main reasons lead to high pollution and high emissions.

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.

There is strong demand for redevelopment of the sites of industrial enterprises having been shut down or relocated (hereinafter referred to as industrial contaminated sites) due to its good geographical location. Direct development of contaminated sites without any remedy and restoration will bring prominent risks of environmental security, health and society. The government must pay high attention to this issue. This paper analyzes environmental risks and relevant supervision departments in different links of the process from relocation to redevelopment of industrial sites. Based on these, this paper presents the whole-process mechanism for prevention and control of environmental risks of the relocation, flow (land use change) and post-flow stages involving several government departments such as industry & information department, national land department, housing and construction department and environmental protection department. This study could provide an important reference to the establishment of effective joint supervision mechanism for redevelopment of contaminated industrial sites in China.

As the incomparable advantages, permanent magnetic synchronous motor (PMSM) has been used widely in servo system, numerical control machine. The paper introduces an EKF (extended Kalman filter)-based sensorless vector control system of permanent magnet synchronous motor. The rotorfield-oriented control strategy based on id=0 is selected. After expounding the principle of EKF and recursion algorithm, it derives the Kalman state equation in PMSM rest coordinate, makes a discretization processing, and constructs vector control system based on EKF estimator. The simulation model of vector control system of PMSM with MATLAB/Simulink is built and on this basis, it observes the position and speed of the motor rotor by the use of the EKF estimator. Simulation results demonstrate the EKF estimator can accurate estimates of the PMSM rotor position and speed.

A set of measurement system for the testing of transmission lines, composing of wireless center station, wireless current acquisition and transmission nodes, wireless voltage acquisition and transmission node, was designed, which was based on wireless communication. The high speed wireless bridge working at 2.4GHz together with the clock synchronization module based on the IEEE1588 communicating protocol were both employed for the communication and time synchronization separately. The measurement system has data storage, waveform display, data analysis, automatic report generation and other functions. The measurement system can greatly reduced arrangement of cables, thereafter improved the test efficiency.

This paper introduces a method of network status feedback and realization based on the analysis of big data. Firstly, millions of structured log of session related were converged to HDFS via Flume System. And then the data of session setup time and session success rate were acquired by Hive or Pig. The function of the two variables has been given by MATLAB. Finally, this function has been integrated in the bottom SDK. It can reflect the state of the network accurately, thus eliminating the anxiety state of users. It can well ease the tense mood of users who are waiting for the results coming from server. Obviously, this approach can improve the user experience.

A defect feature extraction algorithm which depends on the separation and subtraction of color image and mathematical morphology is proposed in this paper, based on the defects in trademark printing processes, such as smudges, pin holes, misprints, misting etc. The difference images of each monochrome are operated with morphology methods and then the defect information of high precision printing processes in colorful trademark, such as shape, boundary contour, quantity, size and location etc, are extracted and recognized with suitable structure elements. The defect extraction algorithm is programmed and run by MATLAB and the results validated the high speed and precision of the algorithm about extracting some kinds of defect information in color trademark printing processes. The algorithm has met the real-time requirements of defect feature extraction in trademark printing processes. This research laid a theoretical foundation for researching and developing the color trademark quality detection system.

Currently, the research of marine dual fuel engine is rare, while the combustion process of marine dual fuel engine is no precise conclusion. This paper built a combustion model of dual fuel engine by AVL FIRE software, and compared experimental data to prove the accuracy of the model, analyzed the characteristics in combustion process of marine dual fuel engines, provided a theoretical basis for the further optimize and design of marine dual fuel engine.

In this paper the drawing process of Box-torque was simulated by Dynaform, which is FEM simulation software. The process parameters, which affected the quality of forming, were optimized by finite element simulation. The emphasis was focus on the optimization of draw-bead and BHF and data were summarized from the optimization graphs. In this simulation, lengthways draw-bead was set on the technical face for reducing or eliminating wrinkle. It was innovation difference from the usual that the draw-bead was set on binder. Finally the correctness of simulation was approved by comparing the optimization of simulation with the data of experimentation.

For the multisensor time-invariant system with both the uncertainties noise variances and parameters, by introducing a fictitious white noise to compensate the uncertain parameters, based on the minimax robust estimation principle and the Lyapunov equation method, a robust weighted measurement fusion Kalman filter is presented. It is proved that for prescribed upper bound variance of fictitious noise, there exists a sufficiently small robust region of uncertain parameter perturbances, such that its actual filtering error variances are guaranteed to have a conservative upper bound. A simulation example shows how to search the robust region, and shows its good performances.

Fuzzy evaluation method is a comprehensive evaluation method based on fuzzy mathematics. It is widely used because of its characteristics for clear results and strong system, and it can solve the problem of fuzzy and difficult to quantify. This paper using an automobile enterprise as an example introduces the application of fuzzy safety evaluation method.

In view of the high precision requirements of the more complex stamping parts of the springback law, this paper put forward a rebound closed loop control system model based on the improved Fourier transform. First of all, starting from the product model, it use the method finite element analysis and the forming process parameter optimization for the initial mold design, and then to measure the mould and stamping products and assess the springback error. Finally, eliminating the springback error through two iterative loops to complete the final mold fixed compensation. Experiments show that the system can complete the mould shape correction effectively by using the model and realize the springback compensation of complex stamping parts.

This paper takes gray prediction forecasting model as a tool to forecast the real estate market in Urumqi from development and investment, construction housing area and sale of housing area. The difference between the actual value and the predicted prediction value is small, with high accuracy. Predictive value can be reflected in the coming period of the real estate market situation in Urumqi. From the predicted results, we could know that there is a lot potential in Urumqi real estate market in next few years and investment in real estate the construction housing area, housing area of real estate sale will get a larger annual growth. In general, there will be increasing potential in the development of the real estate market in Urumqi. Meanwhile, Urumqi real estate market will tend to rationally develop under the regulation of government in the next few years.

Ultra High Strength Steel (UHSS) hot stamping technology is a special process which can enhance the steel tensile strength to 1500MPa. Appling this technology in producing vehicle structure parts can make car lighter and safer. In China there are more and more automobile enterprises adopt this technology. To master and extend the skill, China Academy of Machinery Science & Technology (CAM) have done systematic research, such as the strengthen mechanism of the steel, hot stamping key devices designing, forming and quenching integrated mould designing, stamping process parameters optimization, etc.. By now, CAM has mastered the mass production technology of vehicle parts, which can guarantee its shape and tensile strength, and produced such typical parts as door-beam, B pillar, etc.. The paper is an introduction of the research work and achievement about UHSS hot stamping developed by CAM.

Due to the yield strength σs, tensile strength σb of high-strength steel is much higher than original one, it is applied in making auto’s structure parts to improve the security of passengers and reduce the weight of auto. To make the production of the cold-stamp parts easier, the paper analyzed the structure of a classical part, door-beam, and found that the surface of the part should be G1 continuity at least, rather than G0 continuity. The G1 continuity part has more uniform thickness, less inner strain, and more safety from cracking.

There is a relationship of unity of opposites between the construction and operation period of the project.When the construction period of the project is shorten and the project is put into production in advance, income of operation period will be increased, at the same time, it will cause the increase of construction cost.Combining time-cost optimization with the financial evaluation of the project, from the perspective of the owner, on the basis of considering the capital time-value and the impact of large equipment replacement on the income of operation period, time-cost dynamic optimization model which maximize the project life-cycle net present value and is proved to be necessary and feasible through the case is established.

The paper analyses problems of a lead-zinc ore from Yunnan with a sink and float test. In the paper, we explored the possibility of pre-discarding about the ore by dense-media process. Dense liquids with the specific gravity of 2.6, 2.7 and 2.8 were used in the test, respectively. -12mm crudes were taken into the test. Finally, it revealed that pre-discarding by dense-media separation can be used in the ore. 2.7 was taken as the best specific gravity of separation. 12~1mm was used as the optimal fraction of pre-discarding by dense-media separation. Pre-discarding rate was 45.53%. The light product with a lead grade of 0.29% and a lead recovery of 4.29% was pre-discarded in which the grade and recovery of zinc were 0.22 and 5.84, respectively.

Loess based copolymer (L/CoPolym), a typical silicate minerals / copolymer composite, was used as polymer adsorbent for removing basic fuchsin (BF) in wastewater. Under the optimal condition of adsorption, the removal rate of BF reached to 98.2%, and the adsorption capacity got to 565.0 mg/g. Adsorption dynamics were consistent with pseudo-second-order kinetic model and isotherm model can meet the Freundlich isotherm.

A reasonable prediction of low flow years in a region in the future so as to make deployment in advance is related to the stability of the region. This paper established conventional GM (1,1) model and improved GM (1,1) model based on grey system theory to predict low flow years in the upstream of Zhang River which has gray characteristics so as to avoid risks, improve spatial and temporal allocation of water resources and promote sustainable development of the basin. The research shows that improved GM (1,1) model which can improve the smoothness of the original data series provides a more accurate prediction than conventional GM (1,1) model by using the example of Zhuozhang River tributary in the Upstream of Zhang River.

Support Vector Machine (SVM) method is suitable for machine learning. In order to detect pathological information from tongue diagnosis rapidly, noninvasively and objectively, a near infrared spectral identification model is proposed based on SVM. The tongue spectral data of healthy people and hepatitis patients were collected. Twenty two samples were obtained for individual groups, and for each group, fifteen samples were randomly selected and used as the training sets, while the other seven were taken as the prediction sets. For the data sets, The effects of the principal component number, kernel parameters, and kernel functions on the identification model were investigated respectively. The results showed that the penalty parameter c was always 0.25, not related to the values of the principal component number and kernel parameter g. The kernel parameter g decreased along with the increased number of principal components, and ultimately reached a relatively stable value. When the Radial Basis Function (RBF) was applied, the established model was the best, indicating that the SVM approach is feasible to classify and recognize tongue near infrared spectroscopy, as along as right parameters are selected. This can provide a novel tongue spectral analysis method to distinguish healthy individuals from hepatitis patients.

Based on Pseudo random noise codes of Chinese COMPASS Navigation Satellite System (CNSS), opened access at the end of 2012, space-surface bistatic synthetic aperture radar (SS-BSAR) passive imaging system is investigated. Furthermore, a modified Range Doppler (RD) algorithm that takes direct signal as reference signal in range compression is proposed. The good imaging performance of SS-BSAR system is demonstrated via modified RD algorithm simulation results.

With the development of information technology web-based teaching and learning have become an indispensable part in distance education. However due to the lack of face-to-face communication between teachers and students in web environment distance education in practical operation has inevitably encountered some difficulties one of which is the failure of web-based synchronous interaction. For example, individual learning hasn’t yet been realized in online synchronous discussion. Students have different cognitive styles which play a decisive role on their learning habits and learning behavior. To actualize the individual learning in web-based synchronous discussion, the research has tested cognitive styles of subjects by graphic test, observed performances of the three cognitive styles in web-based synchronous interaction, and analyzed the impact of different cognitive styles on web-based synchronous interaction in terms of cognitive styles and participation, and cognitive styles and interaction quality.

This paper built 5 KVA / 400 Hz medium frequency power supply AC - DC - AC main circuit, Output filter is designed in detail. Based on SPWM control strategy and the voltage RMS feedback loop and PI adjustment, the Matlab/Simulink simulation model is established, and Harmonics are analyzed, the conclusion is obtained.

Converter smelting medium-low carbon ferrochrome replaces electronic by oxygen and reduces production energy consumption greatly. Medium-low carbon ferrochrome end sulfur content analysis is necessary to determine the product quality. Now we still use the product sampling, laboratory analysis to determine end sulfur content, which can not realize online monitoring. According to this status, a PLSBP prediction model of end sulfur content has been established based on particle swarm algorithm, which combined partial least squares method and BP neural network. At the same time, A feedback compensation model has been established by dichotomy, which avoided the model failure caused by raw material quality change. The simulation results showed that the hit rate of prediction model was 96.67% within the absolute error, 90% within relative error. High precision was achieved, which provided an important theoretical basis to improve product quality and optimize the production process.

The tailing in a large lead-zinc-iron-sulfur multi-metallic mine has rich reservation in variety of metallic minerals. It has been difficult to recover because of all kinds of reasons. The challenges faced by lead-zinc ore beneficiation are, low grade and recovery of lead and zinc concentrate for fine disseminated grain size, high oxidation rate and close intergrowth. This paper presents a Pulp Potential Control Flotation by stages technique to improve the flotation performance of the lead-zinc ores. In the electrochemical potential controlling flotation processing, using DDTC as collector, the separation potential range of galena and sphalerite with pyrrhotite can be achieved. Flotation circuit of lead-zinc-silver tailing ore was achieved.

Rich land resources in Henan Yellow River floodplain as well as China's new rural construction strategy provides an opportunity for new rural construction in Yellow River floodplain of Henan province. In this paper, the flow changes before and after the floodplain 2D hydrodynamic mathematical model to simulate the village station construction, water changes can clearly reflect the village station, near the village before and after the construction area and the upstream and downstream, contribute to the analysis changes in hydrodynamic conditions before and after the village station construction and effect on the river regime change.

Wall cracking is a universal phenomenon existing in the composite structure house, prevention and control of masonry crack is a systematic project. the reason of crack on the temperature change, uneven settlement of foundation, construction factors and dry shrinkage of material.It put forward the corresponding control measures：to set reasonably temperature expansion joint, settlement joint and adopt construction measures when designing structure;to make reasonable arrangements for the construction of the roof insulation layer ,trying to avoid high temperature season; As for the materials,it is recommended to use fiber mortar to improve the waterproof performance of the wall.Above all, the paper want to show that cracking control can be achieved by the close coordination of all aspects of design, construction, supervision.

Based on the internal configuration pattern of Dongba Characters, we analyzed the replacing-element configuration method. Applying this method, we combined the concrete Dongba characters with the abstract characters, using either Chinese characters’ structure or Dongba characters’ structure as the basic frame. Further, we used some softwares like “Edongba” to make computer-aided design. This designing method can improve the expression in addition to text connotation, enhance visual image, sculpt beauty, and highlight artistry. It is a new way to inherit and enrich our national culture.

This paper proposes a distributed integrated quality of service (QoS) multicast routing algorithm, which based on genetic simulated annealing algorithm, for the wireless sensor networks (WSNs).The basic idea is to grade the huge and complicated network, and decentralize resource requirements and the computational overhead of source routing algorithm to the various nodes. In this way, each node just needs to know partial information and make local decisions. In addition, simulated annealing algorithm is introduced into genetic algorithm (GA), whose cooling schedules will be more sophisticated through adjustment of temperature attenuation function, combined with improved adaptive crossover and mutation probability though and heuristic crossover and mutation strategy, which can overcome premature convergence and low searching efficiency in late evolution of the genetic algorithm, also improve evolution speed of the simulated annealing algorithm. The algorithm can meet different QoS requirements of services, and have better performance than the original algorithm.

With the aim to determine parameter influences of a measurement system based on optical feedback interference in a laser diode, a mathematic model of optical feedback interference effect is built. LabVIEW which is a kind of graphical programming language is used to realize parameter setting and graphic display by front panel and program chart. Experimental results show that the stripes of optical feedback interference effect are saw-tooth-like waveform when feedback level factor is less than and close to 1, which can be used to determine moving direction of external reflecting object. Feedback interferences generate when vibration amplitude of reflecting surfaces is greater than λ/4. The stripe number is 4N when vibration amplitude dL equals Nλ. Vibrational frequency of external reflecting surface equals the frequency of feedback interference signal and has no influence on stripe number in a period. Measurement of external reflecting object based on optical feedback interference effect has measurement precision less than laser wavelength and real time direction recognition ability.

AOD furnace Smelting Ferrochrome is a complex process. The discretion of the impurity content of phosphorus is one of the important factors affecting the quality of ferrochrome products. If ferrochrome phosphorus excesses, the product is easy to break. At present, the most detection methods of determination the end phosphorus content are artificial experiments, so efficiency is lagging behind. It is necessary to establish a model to predict end-point phosphorus content for improving production efficiency, reducing costs, saving energy consumption. The important influence factors of AOD furnace smelting ferrochrome end-point phosphorus content were determined based on analyzing response characteristics of hot metal dephosphorization pretreatment and thermodynamic condition, the control variables of the end phosphorus content were fixed. According to Sinosteel Jilin Ferroalloys Co., Ltd 5t AOD furnace smelting medium-low carbon ferrochrome technology and production data, a prediction model for AOD furnace smelting ferrochrome end-point phosphorus content has been established based on RBF artificial neural network in accordance with the ferrochrome smelting process for online prediction of end-point phosphorus content. Results showed that the prediction precision of target shooting is 85.7% within the error 0.003%, which has provided important theoretical basis on improving the smelting process and product quality.

Detailed characterisation and recovery of galena, sphalerite, and pyrrhotite from the beneficiation plant tailing of YouXi, China, was investigated. Different characterisation techniques viz. size analysis, chemical analysis, mineral analysis by Mineral Liberation Analyser（MLA）were carried out. Based on the appreciable differences in specific gravity, floatability and magnetic susceptibility between the desired lead, zinc, sulphur minerals and the gangue minerals, the flow sheets comprising desliming, flotation and magnetic separation, was used to recover galena, sphalerite, and pyrrhotite values. A lead and zinc concentrate of Pb 16.02%, Zn 35.1% and sulphur concentrate assays 35% S and 56% Fe can be produced from the tailing.

Traditional measurement and modern SEM-based mineral liberation analysis (MLA) system were employed to obtain the process mineralogy characteristic of Jinshan gold ore which had high Au (6.20g/t) and low sulfide (0.25%). XBSE, XBSE_STD and SPL_Lt MLA modes are used in this case, which make the results timely, reliable and quantitative. The gold behaves irregular granular native gold or silver-bearing native gold of which the Au content ranging from 93%to 100%. Gold mainly occurred as liberated or in gold-carrying gangue minerals, such as quartz and biotite,rarely in pyrite in the form of fissure gold, inter-crystalline gold or inclusion gold . The particle size of the Gold minerals range from 0.001mm to 0.010mm , which is too fine to recover from beneficiating method. Combined process should be adopted.

To investigate the influence of the ball grinding time on the particle sizes of the negative ion powder and the release ability of negative ions for dental applications. Ethanol as a dispersant , steel ball as grinding media, the negative ion powder was grinded (4h, 8h, 12h, 16h, 22h) through the ultrasonic dispersion and ball milling and high-speed mixing process. Its crystal pattern, particle size and surface morphology were characterized by XRD, dynamic laser scattering instrument, SEM. The number of negative ion in different grinding time was tested by 3010-pro negative ion tester. With the increasing of the milling time, particle size of negative ion powder was gradually decreasing, after 22h, the particle size was 232nm, which was consistent with the results of electron microscope, but the number of negative ions was not significantly changed. Therefore, optimum utilization of the ultrasonic dispersion and ball milling and high-speed mixing technologies is necessary to most efficiently achieve stable dispersions with the target particle size characteristics.

300M ultra high strength steel, a new type of steel with broad prospects for development, has good mechanical properties, and is widely used for manufacture of aircraft landing gear. In order to reveal influence law of cutting parameters on milling force of 300M ultra high strength steel, the influence law of feed rate, milling width, and depth of cut and spindle speed on milling force is firstly studied through the single factor experiments in this paper. Secondly, the influence level of experimental factors is compared by orthogonal experiment. Finally, combined with orthogonal test data and the least square method, the multiple linear regression model of milling force in 300M ultra high strength steel milling is built. The accuracy of the model has been verified well by experimental verification, which has the guiding significance to reveal the milling mechanism and actual production.

In order to organize and manage the heterogeneous and volume geographic information resources efficiently for a 3D Digital Earth platform, this paper designs the Resource Mapping System (RMS) and implements it in the Henu Digit Earth (HDE) platform. And the framework and key technologies of the RMS are also discussed.

This study aims to enhance the bacteria’s ability to degrade phenol by exploring the phenol-degrading capability of hybrid strains and immobilized cells. Two phenol-degradation strains named as A1 and A2 were isolated respectively.The StrainA1 was identified as Burkholderia, while strain A2 was found to be Bacillus cereuswere. In addition, conditions including inoculum strains , pH value, temperature and dissolved oxygen were tested. . It was shown that: (1)Hybrid strains ( mixed A1 with A2) was better than single strain(A1 or A2) in degrading phenol because of the Synergistic effect. It can completely degraded phenol at the concentration of 300mg/ L, 500mg / L, 700mg / L within 12h, 24h, 48h respectively. (2) The optimum environmental conditions of phenol degradation for hybrid strains culture is 35°C, pH is 7.0, the inoculum strains is 10%. (3) It is beneficial to the degradation of phenol, when the speed of the shaker was improved. (4) Phenol-degradation rate and the tolerance of high concentration of phenol were significantly improved when the A1 and A2 were mixed immoblized.

Due to the rapid development of aerospace industry, the amount of cutting data is increasing. Establishing cutting database for aerospace industry is necessary. Therefore, this article designs the typical aerospace material database system. According to project requirements analysis and the conceptual design, nine function blocks is set. They are data management, experiment management, optimization management, cutting tool design, cutting tool simulation, knowledge base, aerospace solutions, systems management, and help. And the article describes content and processes of every function block.

As application of gravity platform is increasing rapidly in marginal oilfields, the heat preservation performance of the submarine oil tank is becoming more and more important in offshore oil storage technology. In order to enhance heat preservation performance of the concrete oil tank to reduce energy consumption, three insulation solutions were proposed in this paper. Contrastive analysis shows that polyurethane solution can not only maximize economic benefits but also possess high engineering feasibility and environmental value.

Regenerating codes are a class of erasure codes for distributed storage. The use of regenerating codes not only improves reliability of distributed storage systems, but also minimizes repairing bandwidth when storage nodes failed and need to be repaired. In this paper, we investigate the cyclic structure of hybrid regenerating codes which each node has two fragments with the first fragment stores original message and the second fragment stores parity message. A fast repairing algorithm is also proposed.