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Carbon nanodots (CDs) have been synthesized by chemical oxidation of C6H12O6 in NaOH solution . The as-prepared CDs possess strong blue luminescence.KH560 serve as coupling agent to modify the quantum dots by the method of ultrasound reaction .Finally the obtained C-dots powder have been successfully grafted with quercetin,which is one kind of flavone .This process made the drug have better thermal stability.

Motion precision is an important evaluating index to evaluate the quality of the mechanisms. On the premise of fully studying the motion of joystick in the excavator, a new kind of joystick-control mechanism is proposed. The dynamics simulation model of the mechanism is constructed by ADAMS, so the dimension error and initial angle error of joint in the installation is analysed. Random sampling method are adopted to simulate the error of position of two key points, the simulation of transverse and longitudinal swing of is completed, and the effect on the motion precision of joystick is compared which is made by error of each direction of two key adjusting points. The motion reliability of the joystick-control mechanism is calculated, combined with the stress-strength interference theory.

The design and debugging of motor control algorithm for electric drive tracked vehicle as the research object, this paper proposed a graphical model programming method of the code directly generated based on vector control algorithm model of the permanent magnet synchronous motor created in Matlab/Simulink. After simulation analysis and verification, this paper using real time toolbox automatically generated the embedded C code and implemented a processor in the loop test. The test results show that the longest running time of the control algorithm was 7.1633μs, between code and algorithm model, had high functional equivalence .This programming method is simple and intuitive, easy debugging, stable operation, and provides an effective way for motor drive system software development of electric drive tracked vehicle.

In order to manage the power of electric drive system effectively and improve the fuel economy and working efficiency of electric drive tracked vehicle, this paper proposed a novel energy management control strategy based on the theory of threshold logic and fuzzy logic. The mathematical models of the key components of electric drive system were built in SIMULINK. To examine and analysis the efficiency of control strategy, a driver-controller based HILS (hardware-in-the-loop simulation) platform was built and the energy management control strategy was verified. The simulation results reveal that the strategy have excellent performance in energy distribution, fuel saving and working efficiency, and the proposed control strategy is simple and easy to realize in a real controller, which provides an effective method for the design and application of energy management control strategy of electric drive tracked vehicle.

According to the actual conditions of a high artificial backfill soil slope in a large thermal power plant’s in karst region with very developed caves in Guangxi Zhuang Autonomous Region, we carried out a number of slope monitoring works in order to timely and accurately getting of the stress and displacement distributions of slope retaining structure, to ensure safety of the thermal power plant, and to verify the safety and reliability of the slope design. Through a large number of monitoring data, obtained the development and change rules of the displacement, reinforcement stresses and anchors tension of the slope protection pile and retaining wall. Monitoring data shows that the design for the slope engineering has a good effect, and slope retaining structures are stable as a whole during the monitoring period. This research provides reference in design and monitoring for other projects in this area.

This paper presents a new method to locate partial discharge source of transformer single-winding with the transformer single-winding model and Matlab software simulation. This transformer single-winding model is composed of 300m long wire, which is equivalent to the parameter model composed of only capacitors and inductors through the frequency characteristic analysis of transformer winding. In the process of simulation, the bushing and neutral point current of transformer winding are measured when partial discharge occurs in different position. Then we can get position factor related to the current mean and variance measured through calculation, analysis and deduction. Accordingly the position of partial discharge can be found by corresponding relation. This simulation indicates that this method is effective and practical.

With the rapid development of electric power construction , transmission lines and the surrounding geological environment influence each other that has become increasingly serious, however, there is not formed yet a set of complete and more scientific geological environmental evaluation system in transmission lines at present. In this paper, on the basis of using the experience of other industries of geological environmental evaluation research , study and put forward the geological environmental evaluation method specifically for transmission lines. Evaluation system is established for transmission lines in planning period and construction period , and also put forward the corresponding evaluation index. The research conclusion can provides theoretical support and maintenance for transmission lines of the whole life cycle design,and it also provides reference in designing transmission lines plan and preventing, and controlling geological environmental problems of transmission lines for the decision-making department.

This paper, based on the Retinex Color Constancy Theory, proposes a novel multi-view image correction algorithm, which correction effect is very effective. Histogram equalization,retinex processing and color restoration are performed for multi-view images,and extract reflectance which describe object intrinsic properties to eliminate un-consistent light source influence.The experimental results show that corrected images not only have high color contract,also have consistent color appearance with others.

Functionalized magnetic silica nanospheres were prepared by hydrolyzation of tetraethyl orthosilicate (TEOS) on Fe3O4and modification of Fe3O4/SiOx. Structure of functionalized magnetic silica nanospheres were characterized by transform infrared spectroscopy (FTIR) and differential thermal analysis (DTA). Cellulase was immobilized on functionalized magnetic silica nanospheres through cross-linking method. Saccharification rate of the immobilized cellulase is 70 % of that of free cellulase. The saccharification of the immobilized enzymes after 8 continuous uses still have 10 % of the initial saccharification rate, which demonstrate the potential of this immobilized cellulase for biofuel production.

A Homotopic BI neural network model is developed by combining the homotopy theory and the BI neural network model, to improve the defects of the steepest gradient descent algorithm itself, such as low speed converging and liable to be trapped in local minimum. The end-point carbon content and temperature of molten steel in BOF smelting process is predicted by the proposed model and the original. Result shows that the precision of new model is improved significantly. The hit rates are increased by about 5% and 10%, and the forecasting residuals have decreased 16.31% and 8.67% than the conventional ones, respectively. Also, the calculation time of the new model is 10% shorter than BI model.

To investigate the effects of grinding media size on the grinding kinetics of cassiterite-polymetallic sulfide ores, the ball grinding media with diameters of 25mm, 30mm, 35mm and 40mm were studied in a laboratory ball mill. The results showed that the coarse and fine particles obeyed the first-order grinding kinetics laws in the process of grinding and the ball grinding media with 35mm diameter had a significant advantage on grinding up the coarse particles and controlling the generation of fine particles, which could provide theoretical guidance for practical production so that the grinding effects would be improved effectively and the problem of cassiterite over-grinding would also be settled very well.

Vehicle suspension is a MIMO coupling nonlinear system; its vibration couples that of the tires. For the suspension without decoupling, the vibration attenuation is difficult to be controlled precisely. In order to attenuate the vibration of the vehicle effectively, a nonlinear half vehicle model with active suspension is established and a differential geometry approach is used to decouple the nonlinear suspension system. The decoupled system becomes independent linear subsystems, though pole assignment, the vibration attenuation of the sprung mass is achieved. The simulations show that the vertical and the pitching motion of the sprung mass are attenuated greatly, which indicates that the control algorithm is effective.

The grinding kinetics are strongly affected by the grinding media size and style, in order to improve the grinding efficiency and solve the over-grinding problem of cassiterite in the process of grinding in cassiterite-polymetallic sulfide ores plant. A unique double-sphere grinding media has been designed and the grinding kinetics of this media with different diameters for grinding products of different size fractions have been investigated in this paper.

Li2FeSiO4/C composites were prepared from silica waste by a traditional solid-state reaction method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), elementary analyzer, galvanostatic charge-discharge test and electrochemical impedance spectroscopy. XRD results reveal that Li2FeSiO4/C composites fabricated from silica waste have some impurity. SEM results indicate that the particle size of Li2FeSiO4 composites is nearly accord with the particle size of silica waste. Electrochemical measurements indicate that Li2FeSiO4/C composite prepared from silica waste have comparatively good electrochemical performance. It can deliver a specific discharge capacity of 137.6 mAh g-1 at a charge-discharge rate of 0.1 C.

Si and C of rice rusk were used as silica source and pore-forming agent to prepare cordierite-mullite ceramics at 1380°C for 5 h soaking. The Nd2O3 additive was added to improve the sintering properties. The bending strength, porosity, and thermal expansion coefficient were measured. The composition was characterized by X-ray diffraction (XRD). The microstructures of the sintered samples were observed by scanning electron microscopy (SEM). The cordierite-mullite ceramic doped with 2% Nd2O3 have high prorosity and low thermal expansion coefficient, its bending strength reaches 20.55 MPa. The addition of Nd2O3 decreases the mullite formation temperature to 1200 °C

Aluminium titanate-alumina (AT-A) composites were sintered from the precursor powders prepared by two different methods: a simple sol-gel based heterogeneous precipitation method and a traditional blending method. The crystalline phase, microstructure, mechanical strength, sintering properties, and thermal expansion coefficient (TEC) of the sintered AT-A composites were investigated and compared. The heterogeneous precipitation method increases the homogeneity of the precursor powders and improves the mechanical and sintering properties of the AT-A composites. The AT-A composites with a Al:Ti ratio of 2.2 achieve the optimal performance where the bending strength is high and the TEC remains low.

In this paper, flocculation process was applied to the treatment of potato starch wastewater. The Influence of flocculent types, dosage of flocculants, pH, dosage of coagulant aid polyacrylamide (PAM) and sedimentation time on flocculation efficiency was studied, and principal factors of influence flocculation pretreatment of potato starch wastewater and the optimum flocculation conditions were determined by orthogonal experiment. On the optimum conditions which had the advantage of better treatment efficiency with chemical oxygen demand (COD) removal rate of 40.55% , the suitable pH(7) in favour of the following biological treatment, high yield of sludge of 1.59g/L wastewater which could be used as animal feed or fertilizer and increase economic benefits.

Sulfur dioxide is one of the major pollutants resulting from fuel combustion. In this study, CaO and attapulgite were utilized as raw material for synthesizing CaO/attapulgite(CaO/ATP) desulfurizer. The performance of samples was studied in dynamic conditions. Major factors affecting the desulfurization such as weight ratio of CaO to total, types of modifiers, desulfurizer particle size, bed temperature were investigated. The desulfurization agent synthesized under optimal synthesis conditions with an CaO content of 30 wt% and an NaOH modifier, and the desulfurization reaction processed under optimal synthesis conditions with water content of 20~30wt%, a particle size of 1/10 of desulfurization tower diameter and room temperature, exhibit sulfur tolerance of 17.97wt%.