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Recently, the natural mineral resources became short. In the process of fluorite floatation and tailing recycling, the key point is to find out collectors which have good selectivity to fluorite and effective inhibitor of gangue. Most reagents primarily come from agricultural byproduct and some chemical byproduct. However, the tailing mineral is complex and difficult to collect, which brought out accumulation of tailing mineral and water polluted. We try to modify the fluorite collector by use of computer-aided design drawing software and molecular mechanics curve between reagents and useful components in mineral and screen the best reagent. Interaction energy between drugs and fluorite surface is simulated and calculated by molecular mechanics at the atomic level. To determine that the interaction energy between collector and mineral simulated and calculated by molecular mechanics is helpful for demonstrating interaction mechanism. Finally, the better use of tailing mineral is good for environment pollution.

This paper presents a Model-Based approach to develop UAV (Unmanned Aerial Vehicle) autopilot software. It employs Simulink to design the flight controller, Stateflow to implement control logic and Matlab coder to automatically generate embedded C code from the model developed. Software in the loop (SIL) and hardware in the loop (HIL) simulations are performed in the laboratory to validate the software developed. Flight trial cost and risks are minimized and the design cycles are greatly shortened. The feasibility and the effectiveness of the approach are verified through results from lab simulations and field trials.

The optimal design of mineral composition of mould powder is significant for the improvement of quality of slab. This paper applies Matlab computing platform into mould powder proportioning scheme; designs multi-factor and multilevel orthogonal experiment based on CaO-SiO2-Al2O3mould powder system; prepares mould powder with the same content change of proportioning components and measures the melting temperature and viscosity of each mould powder; and establishes the regression relationship between viscosity and chemical components of mould powder by using Matlab to provide multiple pure quadratic regression analysis function of tool kit; analyzes the dynamic relationship between the viscosity of slag system and the content of various chemical components and provides quantitative analysis method for the optimal design of mould powder.

This paper show a parameter self-adaptive fuzzy PID controller which was designed by using fuzzy logical rules, and the rules aiming at characteristics of constant pressure water-supply system such as nonlinear, multi-parameters and long time delay. The controller can online auto tuning PID parameters to select the appropriate control parameters, depending on the working conditions for effective control of the water supply system water pressure regulator. The simulation results show that the control system response quick, over regulation measurement and transitional time is greatly reduced, oscillation time shorten, and the system has strong robustness and good stability.

The Silicon-chrome-green Pigment is synthesized with solid reaction process, and is tested by XRD. Influence of mineralizer on color and mechanism of action are discussed. The variety and content of mineralizer which suit the Silicon-chrome-green Pigment are determined.

To solve the poor robustness problem that object tracking only by fixation fusion based on multiple clues, an online adaptive fusion tracking algorithm based on multiple clues is proposed. the weighting of the different clues is online adjusting based on scene change , the more the feature contributes, the more a larger value, the less the feature contributes ,the less a smaller value. Simulation results show that this algorithm provides better robustness and stability.

Recast layer, micro cracks and thermal deformation limited the improvement of the surface quality of laser processing in precision machining of hard and brittle material. This paper presents a new method which combines low-pressure water jet with laser processing. A comprehensive study on the influence of laser processing parameters on surface quality of an Al2O3 ceramic sheet is presented. The experiment was conducted using ND: YAG laser machine and low-pressure water jet was used as assist. The surface quality of normal laser processing and low-pressure water jet assisted laser processing was comparative analyzed using a 3-D microscopy. Experiment proves that the composite processing of low-pressure water jet assisted laser processing can obtain good surface quality, slight moltenslag and thermal deformation, compared with the normal laser processing.

After Maojiagang two moles was established, beach surfaces between two moles have occurred obvious silt up, rush to silt tendency and have occurred obvious change. The speed that beach surface silts up has occurred obvious change: In first year, it is rapid that beach surface silt up; Second year, beach surface silts up obvious slack off , and reaches balance step by step; After 3 years, beach surface silt up was obvious seasonal change elevation change.

Random walk modeling has been extensively used for oil dispersion studies. However, there is some misusing about the expression. The aim of this study is to clarify the essence of the method. Expressions used in published papers are reviewed firstly, and different methods are discussed. The results show that the random method can successfully predict the dye patch dimensions and the dilution of the dye with time in contrast with the other method. Also, some critical factor in applying the random walk method is emphasized in the paper. Two types of formula used to simulate the turbulent diffusion are discussed. Results have shown a need for care in determining the concentrations from the random walk model.

This paper analysed the unique climatic characteristics of Qinghai-Tibet plateau and the durability requirements of airfield pavement concrete, improved the frost resistance, impermeability and abrasion resistance of pavement concrete by mixing air-entraining and water-reducing admixtures. The relations of content of the air-entraining admixture, strength and frost resistance of concrete were tested systematically in laboratory, the appropriate air content was put forward. The tests shown that the frost resistance, impermeability and abrasion resistance fulfilled the requirements of the plateau airfield pavement. In the field of Yushu Airfield in Qinghai, it studied the raw materials selecting, control of air content and construction technics, ensured the durability of the pavement concrete and gained well effect.

Effect of water-retaining agent on growth and development of three local legumes were studied, in order to provide science basis for revegetation of lead-zinc tailings in Lanping. Testing survival numbers and moisture and proline content in plants, aim at revealing effect of water-retaining agent on plants under drought stress. The results show that water-retaining agent can prolong survival time of plants and keep stability of moisture and proline content in plants under drought stress. Survival numbers and moisture content of plants leafs decrease with prolonging drought stress time, and proline content of plants leafs increase with prolonging drought stress time. There was no significant difference of survival numbers and moisture and proline content in plants on tailings soil with 0.3% and 0.4% water-retaining agent, so 0.3% water-retaining agent was best dosage in tailings soil for revegetation of lead-zinc tailings in Lanping.

In order to select adaptable plants in lead-zinc tailings of Huize, tailings soil and natural colonized plants on tailings were researched. The results showed that Cd polluted badly soil, the content of Cd in lead-zinc tailings soil of Huize was 515.19 times of natural soil in Yunnan; Pb and Zn were major factor of pollution in tailings, the content of Pb and Zn in lead-zinc tailings soil were 120.92 and 78.44 times of natural soil in Yunnan. The heavy metal content have decreased with prolonging accumulation time, and the heavy metal content of tailings edge is significantly lower than the center. There were a lot of natural colonized species on lead-zinc tailings of Huize, ten species were dominant. The ten species were far way from critical levels for hyper accumulator, but could grow under heavy metals stress and have a high tolerance to Pb and Zn, so can be considered as pioneer plants of revegetation in lead-zinc tailings of Huize.

Genetic diversity of 11 intestinal aerobic bacteria isolated from Dendrolimu. kikuchii was analysed, using PCR and ARDRA which used enzyme digestion of cloned 16S rRNA gene sequences. The results showed that 11 strains could be divided into 6 groups on 84% similarity level, it indicated that the intestinal aerobic bacteria genetic diversity was abundant. Sequencing the 6 representative strains’ 16S rDNA and submitting to GenBank, the accession number being JQ308104 to JQ308109 respectively. The 6 strains belonged to Klebsiella sp., Lysinibacillus sp., Brevibacillus sp., Bacillus subtilis, Gamma Proteobacterium and Brevibacillus limnophilus.

Effects of Rhizobium inoculation on plant height (PH), leaf area (LA), leaf net photosynthesis (Pn), leaf transpiration rate (Tr) and water use efficiency (WUE) of stony desertification-grown white clover (Trifolium) by Rhizobium sp. SWFU27, SWFU29 were studied during Spring 2011. Seeds were soaked for 30min in strain SWFU27, SWFU29 cell suspensions respectively, growing individually in autoclaved stony desertification soil under nursery conditions at ambient temperatures. Datum were collected from 90-day-old plants on a sunny day. Rhizobium inoculation by SWFU27 significantly increased PH and LA by 50% and 91.58% separately, and SWFU29 by 129.17% and 158.95. Pn, Tr, WUE for three sets of plants all in turn: SWFU29 > SWFU27 > CK, suggesting that maximum growth of stony desertification-grown plant requires the Rhizobium inoculation to promote the growth, between the two inoculation systems, SWFU29 had a high photosynthesis efficiency, transpiration potential and water use efficiency than SWFU27 and SWFU29 is much light-tolerance species than SWFU27, thereto signify the phenomena that white clover inoculated by Rhizobium sp. SWFU29 is growing better and to be a pioneer dominant in Karst stony desertification area.

Pot experiments with three local legumes (Trifolium repens L., Vicia Cracca L., Medicago sativa L.) were conducted in five different amendment substrates to research into the revegetation in Lanping, Yunnan province. The main factors of restrict growing of vegetation are lack of nutrient, high concentration of Pb 2+ and Zn2+ , poor in water-holding capacity in lead-zinc tailings. Trifolium repens L. and Vicia Cracca L. are taken as pioneer plants of lead-zinc tailings according to characteristics of the three local legumes species during the growth periods about indexes of the seeding survival, height, biomass, chlorophyll content, SOD (superoxide dismutase) and CAT (catalase) activity, TF75 (75 percent tailings soil + 25 percent rural soil) amendment approach is more reasonable for the revegetation of lead-zinc tailings in Lanping based on three local legumes species growth indexes and feasibility.

In this paper, we took lathe as the research object, and established an active vibration control system model based on neural network AVC (Active Vibration Control) system, and the Matlab simulation results showed that the AVC system can reduce vibration effectively and improve the lathe’s accuracy.

Load sharing is one of the main factors that determine gear strength. In this paper, Tooth Contact Analysis (TCA) and Loaded Tooth Contact Analysis (LTCA) have been performed to investigate the effect of tooth surface modification on the contact ratio, load sharing and strength of an orthogonal offset face gear drive with spur involute pinion. The results indicate that the contact ratio of 2.0 or higher could be achieved. The maximum load carried by single tooth and bending stress are significantly reduced when appropriate tooth surface modification is applied to the orthogonal offset face gear drive.

Characteristics of the permanent deformation and surface rupture caused by fault dislocation in 512 Wenchuan earthquake are analyzed in this paper. On the basis of the data from surveying reports and engineering geological reports of some observation station, three kinds of overlying soil model are established and analyzed, the physical parameters coming from clay and sand: thickness 30m and 50m model of the clay, thickness 30m model of the sand and thickness 50m model of the clay containing sand interlayer. Results show: The thickness of the overlying soil is same, but fault dislocation changed, the permanent deformation scale of overlying soil with velocity of shear wave from 250m/s to 500m/s is almost same, but the surface rupture zone is different: shear wave velocity of the soil is low, surface rupture zone becme wide. With thickness of the soil increassing, the rupture zone become wide too. Influence of sand interlayer is small. Considering the setback distance determination, the geometric and kinetic characteristics of faults, regional seismic activity, material properties and thickness of the overlying soil are key factors.

The surface of cultural heritage and façade of historic buildings represent most values. The conservation of such surfaces need special cares, because most of them are non-structural exposed to extreme weather conditions. The refitting and consolidation delaminated surface were carried out using organic resins, like epoxy resins or cement suspension. However the evaluation in the recent years show such kinds of materials are not chemically compatible with historical materials. Based on inspection on cracks of Huashan’s Pictographs and other historic buildings in Shanghai and Hangzhou, a new system composed of adhesives and injection grouts based on natural hydraulic lime (NHL) has been developed for refitting and rehabilitation of delaminated surfaces made of natural stones, plaster and bricks. The laboratory researches and trial areas on site have shown the adhesives based on modified NHL have sufficient bonding strength to hold delaminated stone slices and blocks. Furthermore, they show slow setting and carbonation process, almost same heat expansion coefficient as the lime stone and inorganic historical materials. After exposure of 135days on site, the trial areas show neither cracking nor efflorescence. The application of developed adhesives and injection grouts in the restoration work of historic Shanghai plaster gates of Jiuxinli in Hangzhou, Zhejinag Province, has been observed positively. Because of high performance and competitive price against organic resins, they are expected to be an optimal material system in the future for façade restoration of architectural heritage and monuments.