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In the bioleaching - solvent extraction - electrowinning practices for copper extraction, the solvent extraction process is used to enrich the copper in the leachate to a high lever to make the sequent electrowinning process possible. O/W type of interfacial emulsion always forms at the interface between organic phase and aqueous phase in the solvent extraction practices. Diversified microorganisms were discovered by microscope growing in the interface emulsion of copper solvent extraction. The diversity of them was analyzed by using 16s rRNA gene sequencing. It was indicated that there exist seven categories of bacteria in the interface emulsion, among which common bioleaching bacteria, such as Leptospirillum sp.,Acidithiobacillus ferrooxidans, Metallibacterium sp., are included. The dominant strains are Leptospirillum sp. E4-L9 and Acidithiobacillus ferrooxidans ATCC 23270, which account up to 40.48 % and 38.1 %, respectively. It was uncovered that bioleaching bacteria can be intercepted by interfacial emulsion of solvent extraction to make their population in the raffinate lower and the efficiency of bioleaching decrease consequently.

A novel kind of rubber toughened epoxy was prepared by in situ pre-crosslinking carboxyl-terminated butadiene-acrylonitrile copolymer (CTBN) in the epoxy matrix. The in situ pre-crosslinking of CTBN was initiated by BPO, followed by the curing reaction of epoxy to form the final pre-crosslinked CTBN/epoxy composites. Mechanical properties of epoxy are further improved by the incorporation of pre-crosslinked CTBN compared with its traditional CTBN/epoxy counterparts due to the improved interfacial strength between rubber and epoxy. SEM shows that the size of phase separated rubber particles of pre-crosslinked CTBN/epoxy decreases significantly.

To reduce shrinkage cracks of cement stabilized macadam base and prolong the life span of pavement, layered materials were mixed in cement stabilized macadam to improve its strength properties and crack resistance. In comparison with the blank test, the unconfined compressive strength increases with the addition of layered materials (weighed at 10% of the amount of cement), by 11.6% with palygorskite, 12.7% with kaolin and 8.9% with montmorillonite, respecetively, at the curing age of 28 days; dry-shrinkage coefficient reduces by 28.2% with palygorskite, 19.0% with kaolin and 14.2% with montmorillonite after 48 days, respecetively. Microstructure of cement pastes mixed with layered materials were observed by scanning electronic microscope. The result shows that more fibrous hydration products and a net-like microstructure exist in cement pastes with palygorskite. It may explain the maximum decrease in shrinkage cracks of palygorskite-mixed cement stabilized macadam.

Shunt Active Power Filter (SAPF) is a new device for compensating harmonic currents in power system [1]. For unbalanced three-phase four-wire circuits, it need detect the total of harmonic and fundamental negative sequence and zero sequence currents at the same time. Base on traditional method of ip-iq, a detecting method which is suitable for unbalanced three-phase four-wire is proposed and analyzed by mathematical reasoning. At last, correctness of the result is verified by simulation.

ADRC is Active disturbance rejection control,it inherits from proportional–integral–derivative (PID) the quality that makes it such a success: the error driven, rather than model-based, control law; it takes from modern control theory its best offering: the state observer; it embraces the power of nonlinear feedback and puts it to full use; it is a useful digital control technology developed out of an experimental platform rooted in computer simulations. ADRC is made possible only when control is taken as an experimental science, instead of a mathematical one. It is motivated by the ever increasing demands from industry that requires the control technology to move beyond PID, which has dominated the practice.

According to the practice of city gas odorization, the technological thought that the diffusion behavior of natural gas in soil was indirectly reflected by the adsorption capacity of tetrahydrothiophene (THT) as an odorant of natural gas in soil was put forward and explored. The adsorbed amount of THT in soil samples by gas chromatography-mass spectrometry (GS-MS) with purge and trap was determined. The impact of four parameters (namely gas leakage, water content, particle size and texture of the soil) on the adsorption properties of soil was then quantitatively analyzed. The experimental results showed that at initial stage of adsorption, the adsorption capacity of THT in soil sample was linear positively correlated with gas leakage and was negatively correlated with water content of the soil and there were no significant differences between particle size and texture of the soil and the amount of THT.

The study on the property of modified asphalt was based on sulfur modified asphalt,s environmental protection and microscopic analysis . The spectrophotometric,s method of methylene blue was adopted for testing release quantity because of the process of reaction producing hydrogen sulfide (H2S) gas between sulfur modifier agent and asphalt, the results showed that gas release quantity of environmental pollution were small which had good environmental protection performance; The analysis of SEM found modifier agent can be evenly dispersed in asphalt; The method of asphalt four components was used to study the compatibility of sulfur modified agent for asphalt, Modifier can absorb part of saturates and aromatics, however, colloid and asphaltene had no absorption; DSC showed that saturates and aromatics can be easy to react with modifier because their poor stability, while colloid and asphaltene were on the contrary.

In order to solve the problems existing in the traditional architectural design process, so as to realize the green building model of task coordination, this article through the analysis of the architectural design work in the process of information flow characteristics, based on green building information model of collaborative design decision-making system, to supervise and control the information flow process. IDEF0s method is applied to traffic simulation model was set up at the same time, in order to realize the green building effective connection each process, various professional and task coordination, maximize the efficiency of the total project life cycle, the purpose of improving the efficiency of resource utilization.

New energy generation parallel operation is an effective way for large-scale development and utilization of new energy generation. The instability of new energy, however, can bring a series of negative influence to stability of power grid. Adjusting the power fluctuations of new energy generation, achieving real-time output stable control, is one of the key technologies of stable operation. The hybrid energy storage system, including lithium ion battery and super capacitor, can reduce the fluctuation effectively. Then it can make new energy generation steady run. In addition, it can reduce the volume, weight and cost of the energy storage system compared with the single battery or super capacitor energy storage.

AZ31 and AZ61 magnesium alloys were discharged in 1.2mol·L-1 MgSO4 solution to investigate their performances as anode fuel material in metal-air fuel cells. The results show that aluminum in alloys takes part in the discharge process and forms the colloid of Al (OH)3. The Al (OH)3 facilitates Mg (OH)2 dropping from the surface of alloy electrode, which results in the more negative and stable discharging potential of AZ61 alloy than AZ31 alloy. The discharge efficiency of AZ31 alloy is less than AZ61 alloy because of the more server negative difference effect of AZ31 alloy.

Ancient village Azheke, located in Yunnan province in China, surrounded by magnificent Yuanyang Terraced Field and lush forested Mountains, is an excellent living model of Hani people’s vernacular landscape reflecting the wisdom of sustainable land use, agricultural cultivation and stewardship. However, the overwhelming globalization and urbanization construction bring about many problems to the ancient village, such as the currently deteriorating of natural environment, the declining of the ancient knowledge and skills of agricultural cultivation, the discarding of traditional life style with meaningful distinctive traits and the oblivion of cultural identity and religious spirits. Targeting on these challenges, this paper proposes a holistic approach to revive and rescue the ancient village. From the perspective of landscape, this study divided the vernacular cultural landscape into four processes, i.e. ecological, productive, daily & social life, spatial & religious landscape processes, considering the ancient village as an organism with its living demands. Based on the methods of scenes recovery and regeneration of vernacular landscape security network, this approach restores the scenes with the critical landscape elements in Hani vulgar life and unique culture, and respectively regenerates the ecological, productive, daily & social life and spiritual & religious vernacular landscape security network, according to the study results from literature and field observation and investigation. Then, after superposing these four networkers, an integrated village conservation framework is generated, with the complete elements, perfect function and distinctive traits. This strategy leads a way for achieving the objective of holistic conservation and revival of ancient village Azheke, which provides a reference for the ancient villages conservation in the World Cultural Heritage areas of Hani Terraced fields.

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

For a novel electric clutch actuator, a nonlinear feedforward-feedback control scheme is proposed to improve the performance of the position tracking control. The feedforward control is designed based on flatness in consideration of the system nonlinearities, and the linear feedback control is given to accommodate the model errors and the disturbances. Lookup tables, which are used to represent nonlinear characteristics of the actuator systems, such as friction force, appear in their original form in the designed feedforward controller. The designed controller is evaluated through simulations and experimental tests, which show that the proposed controller satisfied the control requirement. Comparison with PID control is given as well.

Regular hexagonal plates of magnesium hydroxide with high slurry concentration were prepared by hydrothermal reaction without any organic additive or catalyst using bischofite and ammonia as raw materials. The effects of hydrothermal temperature, stirring speed, hydrothermal duration, and dilution multiple on the preparation of Mg(OH)2 flame retardant were investigated. Scanning electron microscopy, X-ray diffraction, and laser particle analysis were performed to characterize the product morphologies, structures, and size distributions. Results indicated that the growth direction of Mg(OH)2 crystal changed, and the regular hexagonal plates of Mg(OH)2 with uniform particle size and high dispersion characteristic formed after hydrothermal modification treatment. A mass fraction of 15.50% Mg(OH)2 of magnesium hydroxide slurry was obtained by high-concentration (4.30mol/L) magnesium chloride and ammonia as the raw materials.

Harmonics of power system seriously affected the quality of electric power. Active Power Filter (APF) [ which overcomes the shortcomings of passive filter (PF) has become main technology to suppress harmonic. In this paper, development history, key technology, problems and trends of APF are mainly analyzed and reviewed. With development of key technology of APF, it will have a better application prospect.

Land roughness is an important parameter of border irrigation in the surface water flow movement, it affects of the water movement process and affects irrigation efficiency, so it’s necessary combined with field surface other parameters to study irrigation field roughness to the irrigation efficiency. Agreement is good between simulated by SIRMOD model and measured values​​ through field trials the measured data of water flow advance and regression process, and indicating with SIRMOD model can simulate border irrigation process. Four kinds of typical field surface roughness of irrigation simulation by SIRMOD model and analysis of the results obtained: land roughness difference of water flow advance and regression process influence significantly, the water flow advance and regression process is better with the small land roughness, and the curve of water flow advance and regression becomes uneven, so irrigation efficiency significant reduction with the field surface roughness increases.

Microgrid has become one of the most important adjuncts to solve the power system in some developed countries. This article aims to introduce the every country’s definition of Microgrid and its significance, discuss the key technologies in Microgrid research, including control technologies, management techniques and so on; Secondly, I summarize the key problems of Microgrid in current stage; Finally, discuss the trend of Micro-grid in the light of the current development status and problems.

In this paper, the nonisothermal crystallization kinetics was investigated by differential scanning calorimetry for the poly(m-xylylene adipamide) (MXD6) which were prepared by polymerization in reactor. The Avrami theory modified by Jeziorny and Z.S. Mo equation were used to describe the nonisothermal crystallization kinetics. The analysis based on the Avrami theory modified by Jeziorny shows that the Avrami exponent n of MXD6 ranges from 2.3 to 3.3, Moreover, both Avrami exponent (n) were around 3.0, which probably suggests a thermal nucleation and a three-dimensional crystal growth. The good linearity of the plots indicates the successful application of Z.S. Mo method in this case.

Nowadays,all countries around the world have made big efforts on the development of the PV system. As a recently emergent industry, the prospect of the PV system is very great. As a effective mode of using the new energy, the research of the related technologies of the PV system has make a very big progress. This paper makes an introduction about the related technologies of the PV system from two aspects of the controlling technology and the power electronics. And it makes a prediction to the trend of the key technologies.

To investigate the potential bioavailability and mobility of phosphorus (P) in suspended solids, the Standards, Measurements and Testing (SMT) programmers was employed to characterize the distribution of P in suspended solids from different treatment stage of KunmingWWTP.Results showed that: the main form of total phosphorus (TP) in suspended solids was inorganic phosphorus (IP) ,which accounted for 47%~60%.Amongdifferent forms of inorganic phosphorus, Iron-phosphorus was the dominant forms accounted for 82 % of total phosphorus while calcium-phosphorus was only the minor par. Throughout the process, the trend of changes in content is close between total phosphorus and organ phosphorus. Bioavailable phosphorus in suspended solids ranged from 5.903 mg·g-1to7.376mg·g-1 and occupied 89.64%to94.16% of the total phosphorus pool.

Lidar is the main standoff detection system against bioagent/bioaerosol, An infrared lidar has been developed for bioagent/bioaerosol monitoring. The overall architecture and specifications of the lidar were described. The results of overlap coefficient, horizontal and slant measurements at Hefei, such as comparison of observed horizontal extinction coefficients between commercial MPL Lidar and the IRLidar, the slant path time-space extinction coefficient distributions have been revealed and discussed. The results show that the IRLidar is a reliable lidar with advanced performances.

There is a serious security problem in the process of workpieces flipping, which restricts the increase of production capacity in manufacturing process of large workpieces applied in nuclear power equipment. The shapes and characteristics of flipping workpieces were analyzed; the general model of workpieces outer contour was established. The design goals of heavy castings and forgings cold-work turnover mechanism were formulated based on the requirements of turning process, then the basic constraint-face was build and the geometric constraint-model was uniformed. A novelty 3- DOF planar serial mechanism of heavy upender was proposed whose overall configuration consists of three movements, that is roll, mobile, folding turn, which can realize the double function of turning 90 ° and 180 ° of large workpiece as hollow cylindrical, conical and spherical crown three types. On this basis, the airbags-drived flipping worktable was designed; Topological optimization of flipping worktable was further conducted. Its key technology will provide useful ideas and references for the development of large heavy duty positioner and turnover machine with its other related equipment.

ABS(antilock brake system) is one of the most important active safety technology for modern vehicles which could enhance vehicle active safety. In this paper, an improved sliding mode control method based on reaching law has been proposed to solve the vibration problem in traditional sliding mode control. The ABS control strategy has been designed based on the sliding mode variable structure control. On this basis, the ABS single wheel depending on control strategy has been designed to ensure the braking stability. By hardware-in-loop simulation, the results demonstrate that ABS sliding mode variable structure control could enhance braking stability performance and improve the control effect on high friction and low friction road.

Magnesium hydroxide was prepared through direct precipitation using magnesium chloride and ammonia as raw materials. In this paper, we mainly studied the effects of magnesium hydroxide on product characterization when the concentration of raw materials was changed. The products were characterized through laser light particle size analysis, scan electron microscope and X-ray diffraction. The study showed that a sudden change in the morphology of magnesium hydroxide products and in the polarity of the crystal occurred under the following conditions: stirring speed of 2500 rpm, reaction temperature of 60°C, ammonia to magnesium chloride ratio of 2:1, ammonia addition rate of 20 mL/min, and aging time of 30 min. As the raw material concentration was changed, the morphology of magnesium hydroxide products and the polarity of the crystal exhibited sudden change. When the concentration of magnesium chloride was changed to 0.8 mol/L, the product demonstrated a flower-like globular structure, the largest size, and the minimum polarity. When the concentration of magnesium chloride was more than 1 mol/L, the product exhibited a flake structure, no obvious aggregation and a narrow particle size distribution.

In recent years, as the change of the building of aesthetic requirements, building skin is given more and more attention, and the material of the carrier material surface design exposition will play a huge role. In the second half of the 21st century, the living environment and sustainable development has become the focus of attention of the world. Environmental protection concept is being accepted by more and more people. People are realizing the importance of ecological building material to the protection of the environment, the save of resources and the health of human beings. All kinds of ecological building materials receive much popularity among architectures around the world.

Engineered nanoparticles have been extensively used in electronics, energy, materials and biomedical areas. Engineered nanoparticles with unique magnetic, luminescent, and catalytic properties can not only benefit human society, but also cause potentially harmful interactions with living systems. This study was aimed at assessing the cytotoxicity of CuO ENPs, TiO2ENPs, CeO2ENPs, SWCNTs in human lung epithelial cell line (A549). Herein, we performed a comprehensive study on the cytotoxicity of four different ENPs by examining the viability of A549 cells. The results showed that CuO ENPs could cause a highest dose-dependent cytotoxicity, SWCNTs were more toxic than TiO2ENPs and CeO2ENPs to A549 cells, TiO2ENPs induced a slight loss of cell viability at 100 mg/L and CeO2ENPs had no obvious cytotoxicity. These effects were dose related, and should be considered in the application of different areas of ENPs.

A new kind of gypsum retarder was prepared from waste penicillin mycelium (WPM), a harmful solid waste from pharmaceutical factory. The results indicated that the optimum treatment conditions were pH value 11, temperature 80 °C and treatment time 1.5 h. Compared with sodium citrate and sodium polyphosphate, WPM retarder can effectively prolong the setting time of gypsum with less influence on mechanical strength. The crystal morphology microstructure of gypsum containing retarder was studied with SEM and the reason why the mechanical strength loss of gypsum were also explained in this paper.

The material removal process of SiC/Al particulate (SiCp/Al) metal matrix composite by micro-wire electrical discharge machining (micro-WEDM) is influenced by many factors interaction, which makes the mathematical model of surface roughness (SR) be difficult to obtain effectively. To solve this problem, experimental study method is conducted under the constraint conditions. In this paper, a central composite design (CCD) testing with 3-factor and 5-level is carried out and SiCp/Al metal matrix composite machining test scheme is designed, and then second-order relational model is established between SR and main power parameters (open-circuit voltage, capacitance, and pulse duration) by using response surface methodology. Through multiple quadratic fitting, the quadratic regression mathematical model of SR is obtained. Constrains of actual machining condition upon the parameters are analyzed further. With the goal of reducing SR of SiCp/Al metal matrix composite by micro-WEDM, the parameters optimization model is established. Particle swarm optimization (PSO) algorithm and its procedure are designed to solve the model. Test proves that the algorithm could achieve optimized process parameters which satisfy multiple constraints rapidly and effectively.

In recent years, the rapid development of logistics has become the driving force of the construction of Logistics Information Platforms, nevertheless, most of which are still underdeveloped, especially the charging and pricing mechanism of the platform is inadequate. Based on the bargain method of the game theory, this essay will build a pricing model and conduct a three-round bargaining reverse regression calculation towards logistics software customized services, resulting in its optimal pricing strategy. Taking National Transport Logistics Public Information Platform as the analyzing example, this essay provides theoretical support for the optimal pricing strategy of logistics software customized services.

The purpose of this study is to investigate the effect of fucosterol on the induction of apoptosis and the molecular mechanism involved in Human promyelocytic leukemia HL-60 Cells. HL-60 Cells were treated with different concentrations of fucosterol at different time. MTT method was used to study fucosterol anti-tumor activity. Morphology observation was performed to determine the effects of fucosterol on apoptosis of HL-60 cells. Flow cytometry (FCM) was used to detect the cell cycle. Laser scanning confocal microscope (LSCM) was used to analyze the expressions of Fas, FasL, Fadd and Caspase-8. Caspase activity kits were used to determine the activity of Caspase-8 and Caspase-3. The results showed fucosterol could inhibit the growth of HL-60 cells, and the apoptosis morphology for 48 h treatment was obvious, which showed cell protuberance, cytoplasm concentrated and apoptotic body. Fucosterol treatment for 24 h increased the protein expression of Fas, FasL, Fadd and Caspase-8. It also showed that the activity of Caspase-3 and Caspase-8 has increased significantly. In conclusion, Fucosterol could induce HL-60 cells apoptosis via death receptor pathway.

This paper is mainly to investigate the stability of synthetic folic acid under different conditions, including pH, temperature, light, and the presence of antioxidants. The results show that folic acid gives a good stability in the buffer of pH 8.05~10.40, whose reservation ratio can reach more than 93.1% in 72 h, while the preservation ratio of folic acid reduce to 23% in the buffer of pH1.95~6.40. Moreover, folic acid has a good stability in the buffer of pH 5.39~10.40, after water bath at 100°C for 2 h. Folic acid exhibits a good stability under the condition of weak illumination intensity. Increasing illumination intensity promotes a decrease in FA concentration. The combination of antioxidants Vitamin C (VC) and sodium citrate displays a significant effect on protecting folic acid from oxidation.

With the wide application of power electronic equipments in power system, more and more harmonic are poured into the power system, which cause power pollution and make the power quality problem increasingly serious. Active power filter (APF) is an important equipment to compensate harmonic and reactive current in power system. One of the key technologies lies in the real-time and accurate control. The fundamental principles of several control strategies of compensate current were presented, and the respective merit and demerit of these control strategies were pointed out with contrast analysis in this paper. Active power filter will achieve a higher performance and a wider application with the continuous development of the control strategy.

Over the past 10 years, nonlinear dynamics and chaotic theory attracted scholars and people got a deeper understanding of chaos. There are many methods for chaos research, and the method of using topological horseshoe is an important branch of those methods. So far, this is one of the core methods with mathematical rigor for chaos research. Based on simple thinking of geometric space, topological horseshoe build a bridge for numerical and theoretical studies of complex behavior of nonlinear systems so that people can carry out a series of studies for chaotic behavior. This paper introduces the basic content of topological horseshoe theory and the application to a simple power system.

In the situation that the traditional energy shortage and environmental pollution problems have become increasingly grim, the new energy research has been widespread concern at home and abroad. Represented by distributed photovoltaic power is gradually from a stand alone system toward large-scale grid direction. However, the PV system chaotic phenomena threaten the stability of the system.

In this paper, MoS2 nanoflakes was prepared by a vacuum freeze-drying method. Electrochemical performance of MoS2 nanoflakes has been investigated through cyclic voltammetry, electrochemical impedance spectroscopy analyzer. The results demonstrated that the new electrode maintains a relatively high power density and a good cycle performance in 6 M KOH electrolyte. A maximum specific capacitance of 0.11 F g-1 in an aqueous electrolyte solution has been obtained. The supercapacitor devices exhibit excellent long cycle life along with ~ 40% specific capacitance retained after 500 cycle at scan rates of 500 mV s1.

After a distribution network failure occurs, how to correctly and quickly restore power supply to non-fault zone is of great significance to meet the user's power supply requirement and to improve power supply reliability. At first, this paper introduces the research status of service restoration algorithm of distribution network, and then analyzes the advantages and disadvantages of various algorithms. At last, it expounds the problems existing in the current distribution network service restoration and makes prospect of research on the distribution network service restoration.

Succinoglycan is an acidic exopolysaccharide that is important for invasion of the nodules. It is a high-molecular-weight polymer consisting of repeating octasaccharide units. These units are synthesized by a complex pathway encoded by numbers of exo genes. In this study, two key genes,exoAandexoY, were cloned and sequenced, which controlled the first two glycosyltransferase reactions in the biosynthesis of succinoglycan. The sequences contained 999-base-pares (bp) and 681-bp Open reading Frame (ORF) encoding 332 and 236 amino-acid proteins with molecular weights of approximate 36.8 kDa and 25.5 kDa , respectively. The putative proteins, ExoA and ExoY, were analyzed by several online protein analysis softwares. The results showed ExoA and ExoY were the membrane proteins with three (ExoA) and one (ExoY) hydrophobic transmembrance domains. Their theoretical PI values were 9.49 and 9.34, respectively. The second structures analysis indicated that they were composed of 45.48% and 38.94% α-helix, 13.55% and 16.81% β-sheet, and 40.96% and 44.25% random coil structures respectively. These data will lay a foundation for the subsequent 3D structure prediction and gene mutation to improve succinoglycan production.

Existing model of solar cells is not suitable for partial shading condition, which makes output current-voltage (I-V) curve of photovoltaic (PV) array staid-stepping. Furthermore, Power-Voltage (P-V) characteristics may exist more than two local peak value in partially shading which bring interferences to maximum power point tracking (MPPT). Based on modified engineering model of solar cells, an accurate model of array was proposed considering variation of shadows. And the I-V characteristic, P-V characteristic and yield of PV modules were analyzed. At last, the optimum output power with different shadows arrangement was discussed.

The dynamic voltage restorer (DVR), as an important electrical installation, can handle the voltage sags and stable the electrical power system. This paper talks about power system operation problems - Voltage dips, then briefly introduces Dynamic Voltage Restorer basic structure and principles, the then mainly complaint about the dynamic voltage restorer research. At last, it will give us a conclusion and the future development trend.

In recent years, frequent earthquakes have caused great casualties and economic losses in China. And in the earthquake, damage of buildings and the collapse is the main reason causing casualties. Therefore, in the design of constructional engineering, a seismicity of architectural structure is the pressing task at issue. Through time history analysis method, this paper analyzes the time history of building structural response and then it predicts the peak response of mode by response spectrum analysis. Based on this, this paper constructs a numerical simulation model for the architecture by using finite element analysis software SATWE. At the same time, this paper also calculates the structure seismic so as to determine the design of each function structure in architectural engineering design and then provides reference for the realization of earthquake-resistant building.

This paper proposes a general overview of distribution network automation technology. With the continuous development of society and economy, the distribution network automation has become the trend and developing direction of electric power system. As the end part of the electric power system, the distribution network is directly connected to the consumers and plays a vital role in improving the quality and reliability of power supply. In order to provide reference for improving the reliability of distribution network and to speed up the development of distribution network automation, this paper analyses the system structure, development status and trend of distribution network automation technology.

Various fault location methods for distribution network at home and abroad are summarized. According to the fault type,the location methods for short circuit fault and earthed fault are introduced. And the basic theories, characteristics, improvement and applications of the representative methods are analyzed. The main problems in the applications of these methods are analyzed. In view of these questions, users requirements and the development of distribution network, the improvement and research about fault location technical are proposed preliminarily.

Distribution network is the design of closed loop, open loop operation,which segment equipped with a normally closed and normally open switch contact switch,By changing these disconnect switches and contact switch status, the structure of the distribution network reconfiguration, you can achieve a balanced load, reducing network losses and improve voltage quality role.Distribution Network Reconfiguration in mathematics is a multi-objective high-dimensional nonlinear optimization problem, has a great solution space, using the general optimization method is difficult to obtain a good solution.Existing optimization methods such as optimal flow pattern method, branch exchange method, particle swarm optimization, genetic algorithms, computational efficiency and optimization results in other aspects worthy of improvement.

With the development of modern technology, high quality power supply becomes more desirable in everyday life. Among problems related with the power quality, the most urgent is the voltage dip; with the application of power electronics devices, the power system is polluted by harmonics. SMES (Superconducting Magnet Energy Storage) system can not only compensate the voltage dip, but also provide a load-fluctuation compensation and active power filter. In the paper the main structure of SMES system is introduced; the necessity to use SMES are demonstrated by analyzing the problem of power quality. The analysis shows that SMES system is effective in improving the power quality.

A β-(1,3)-D-glucan (curdlan) synthase gene for a low molecular weight curdlan biosynthesis, crdSAg, from Agrobacterium sp. M503 was cloned and its encoding protein was characterized by several online protein analysis softwares. The crdSAg consists of 1965-base-pairs Open Reading Frame (ORF) encoding a protein with molecular weight approximate 73.5 kDa, which contains the conserved domain of CESA-CelA_like belonging to glycosyltransferase family 2 (GT2). Moreover, CrdSAg was a membrane protein with seven hydrophobic transmembrance domains. The second structure analysis indicated it was composed of 43.12% α-helix, 17.89% β-sheet, and 38.99% random coil structure. These data will lay a foundation to clarify the biosynthesis mechanism of the low molecular weight curdlan.

As the additional injection type hybrid active power filter (IHAPF) may exist fundamental circulation between the active part and fundamental harmonic branch, a new topology of injection type hybrid active power filter is proposed to enhance the safety of IHAPF in the paper, this paper discusses the principle of fundamental circulation and the advantage of the novel structure on harmonic voltage of series resonant subcircuit.

The effect of load model on the analyses of load flow, transient stability, small disturbance stability and voltage stability is analyzed. The importance of the load modeling research is emphasized. The development of component-based method and measurement-based method is reviewed. The advances on the load model research including the select ion of load model structure, model parameters identification, load model with the voltage stability analysis and the sensitivity of load model to the transient stability is summarized.

Flexible AC transmission technology (FACTS) is a new technology developed in recent years. It use power electronic technology and modern control technology to achieve fast control for AC transmission system parameter and structure [, to achieve the rational allocation of transmission power, reduce the power loss and the cost of power generation, greatly improve the stability and reliability of the system. STATCOM is based on the principle of reactive power compensation, using full-controlled switching devices to compose self-commutated inventer, complemented by small-capacity storage elements constitute reactive power compensation device. Its role in the power system is the compensation of reactive power, maintain the voltage of the connection point, improve system voltage stability, and improve the steady performance and dynamic performance of the system.

In order to study on the problem of voltage stability of power system, this paper describes the static bifurcation analysis and the dynamic bifurcation analysis in voltage stabilization analysis of power system and its relationship with the voltage stability,discusses the voltage instability caused by two main bifurcation formal definition, the occurrence of the conditions and the calculation of the bifurcation point, and points out advantages and disadvantages of various algorithms. Finally the paper looks forward to further study of the bifurcation theory in terms of voltage stability.

The research of anti-slip control for slurry pump is to prevent the cavitation of pump,protect flow passage components of pump from cavitation corrosion.Through the analysis,the size of the inlet velocity is regarded as the characterization whether pump cavitation.Calculate the five kinds of inlet velocity when the slurry pump is in the normal work, make the procedure is versatility. PLC programs are compiled and imported into hydraulic-pneumatic experimental platform,experimental platform simulates the results of pump system is accord with anti-slip control requirements.The program is used in slurry pump avoids the occurrence of cavitation phenomenon and simplifies the complicated site operation.