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The problem of local minimum cannot be avoided when it comes to nonlinear optimization in the learning algorithm of neural network parameters, and the larger the optimization space is, the more obvious the problem becomes. This paper proposes a new type of hybrid learning algorithm for three-layered feed-forward neural networks. This algorithm is based on three-layered feed-forward neural networks with output layer function, namely linear function, combining a quasi Newton algorithm with adaptive decoupled step and momentum (QNADSM) and iterative least square method to export. Simulation proves that this hybrid algorithm has strong self-adaptive capability, small calculation amount and fast convergence speed. It is an effective engineer practical algorithm. more...

Based on interval arrangement characteristics of the mined branch roadways and pillars in continuous miner filling mining gob,the cemented filling mining thought which divided mining and filling both into two stages was put forward.The first stage was mining branch roadways and then filling gob with cemented materials in time, and the second stage was mining pillars and filling gob with the first stage filling body support when it meet designed strength. Industrial field test showed that branch roadways were smoothly mined and filled, filling body strength meet demand and pillars were safety mined out.Continuous miner filling mining technology could reache high production efficiency based on advantages of mining and filling parallel operation and filling spaces constructing easily. more...

Organochlorine Pesticides (OCPs) is a kind of typical Persistent Organic Pollutants (POPs) with high toxicity, semi-volatility, environmental persistence and bio-magnification. Because of its large number of application in history, the residue level of OCPs in environmental media is rather high. This paper summarizes the existing status of the residue level and distribution of OCPs in China’s lakes in recent years, which is helpful to evaluate the pollution status of the OCPs in lake and provides a basis for effective governance. more...

Full-pillar extraction by filled wide working face layout in strip mining resolved the course of surface deformation and moving into two period drew support from wide working face layout in partial mining, filling in roof falling zone and full-pillar extraction. It could carry point of reducing mining effect and protecting surface.This paper explained technical principle of full-pillar extraction by filled wide working face layout in strip mining, and analysed effect of wide working face partial mining and roof filling in falling zone in this technology, and researched the features of surface deformation and moving with this technology in a demonstration. Resources under buildings and Coal demand increased year by year with rapid development of economy and it speeding up depletion of common resources,therefor,coal seam under rivers,buildings and railways reasonable mining has important significance for improving recovery and relieving energy shortage.Coal seam under rivers,buildings and railways reserves reached 137.9Gt in State owned coal mine according to statistics, which coal seam under buildings makes 94.68Gt account 69% of the total and constraints mine development.To some degree,although traditional reduce subsidence mining technology settled pressed coal mining problems,but its extension limited by low recovery,the high cost,difficult to carry out and the difference with saving resources and high efficient.Full-pillar extraction by filled wide working face layout in strip mining resolved the course of surface deformation and moving into two period drew support from wide working face layout in partial mining,filling in roof falling zone and full-pillar extraction,which could carry point of reducing mining effect.It is one of the technological approaches to make high recovery,the low cost and high efficient in pressed coal mining.This paper analyzed wide working face in strip mining and filling effects in the strata movement control and researched the ground deformation features by an example with Full-pillar extraction by filled wide working face layout in strip mining. more...

Diesel engine emissions of nitrogen oxides and particulates are the major source of air pollution that is a serious threat to human health. Diesel emissions treatment technology meet the increasingly stringent emission standards through the current difficulty and develop a new diesel engine exhausted treatment technology to further reduce the nitrogen oxide and particulate emissions are from diesel engines. In this paper, La1-xAxCo1-yByO3 complex perovskite catalysts for diesel engine exhaust emission purification carry out the relevant research, this article firstly study the perovskite oxide catalyst preparation methods, as the catalyst preparation process are described .Then the activity of the catalyst samples obtain some useful results. more...

The adsorption of acid red G dye onto raw bentonite/cationic starch (RB/CS) and raw bentonite (RB) was investigated in aqueous solution in a bath system with respect to the adsorption kinetics and adsorption isotherms, respectively. For RB and RB/CS composite, the kinetic data showed that the kinetics of adsorption was best described by a pseudo-second-order expression than the pseudo-first-order. Adsorption isotherms of acid red G dye onto RB and RB/CS composite were determined with common isotherm equations such as the Langmuir and Freundlich models. The results showed that for RB/CS composite, the Langmuir model agreed very well with the experimental data, whereas the RB was fitted to both Langmuir and Freundlich models. In summary, the results showed that RB/CS could be employed as low-cost materials for the removal of acid red G dye from effluents compared to RB. more...

The adsorption behavior of acid red G from aqueous solution onto raw bentonite (RB) and raw bentonite/ cationic starch (RB/CS) composite samples was investigated as a function of parameters such as contact time, salt concentration, initial dye concentration and temperature. The results showed that an amount of 0.12g of RB/CS composite could removal more than 90% of dye from 150ml of 100 mg L-1 acid red G solution with a contact time of 60 min, at room temperature and no salt addition. The adsorption rate was fast and more than half of the adsorbed acid red G was removed in the first 10 min for RB and 5 min for RB/CS at room temperature.(Co=100 mg L-1)The results also indicated that the RB/CS composite had a shorter equilibrium time, higher color removal and stronger adsorption properties of acid red G than RB. In summary, the results suggests that RB/CS can be employed as a kind of low-cost material for the removal of acid red G from aqueous solution. more...

Iron, chromium or tin containing mesoporous materials MSU-X were synthesized using Pluronic F127 as templating agent under the neutral pH condition by one-step method. The samples were characterized by XRD, N2 adsorption, TEM, FT-IR, UV-Vis. The surface acid nature of Sn-MSU-X was investigated by FT-IR of pyridine adsorption. The results indicate that Fe, Cr and Sn have been successfully incorprated into the framework of the MSU-X samples. And these samples have an uniform pore size distribution. Fe-MSU-X and Cr-MSU-X exhibit disordered worm-like mesostructure. However, Sn-MSU-X exhibits highly ordered hexagonal-pores mesostructure. The Fe-MSU-X and Cr-MSU-X catalysts are more active for the selective oxidation of phenol and cyclooctane, respectively.There are both Lewis and Brönsted acid sites on the surface of Sn-MSU-X. more...

A series of nano-sized iron oxide supported on 3D wormlike hierarchical mesoporous SiO2 catalysts were synthesized by one-step hydrothermal synthesis. The samples were characterized by XRD, N2 sorption, FT-IR, UV–Vis, TEM and ICP-AES. The catalysts were probed for the oxidation of phenol employing hydrogen peroxide. The results indicate that the materials exhibit high surface area and 3D wormlike hierarchical pore, iron ions exist as isolated framework species when the weight percentage content of iron is below 0.24 and nano-size iron oxide is dispersed in the surface (iron content above 0.24 wt%). Catalytic performance indicates that nano-size iron oxide supported on SiO2 is useful to enhance both the catalytic activity and the selectivity of target products compared with isolated iron species. more...

In this paper, a test system hardware platform based on PXI bus system is proposed to test the airborne power system and typical power distribution structure of large-scale Unmanned aerial vehicles (UAV). By researching system structure, analyzing failure mode and designing fault tree, fault diagnosis expert system is designed to test the airborne power system in large-scale UAVs, where a forward reasoning expert knowledge base based on extension rule is built to solve the non-exact inference in complex system via introducing certainty factor. The experiments illustrate that the proposed system can effectively improve the intelligent level of test system and has good application prospects. more...

This paper in aircraft assembly at home and abroad on the basis of the technical investigation and through the study of domestic aircraft digital assembly backward, serial design, repeatedly modify, multiple test equipment, long production cycle, high cost problems, presented a lightweight model based on process of visual assembly technology. And elaborated this technology to the airplane rig production line vital significance, and proposed the concrete implementation method. Finally adoption of the instance can be seen, lightweight visual assembly of the model based on process technology, the domestic use of advanced assembly technology, construct advanced assembly lines, improve the assembly efficiency, reduce assembly costs are of important significance. more...

A series of mesoporous materials Sn-SBA-16 was prepared by one-step hydrothermal synthesis with F127, TEOS and SnCl4•5H2O as template, silica source and tin source, respectively, without mineral acid added. The samples were characterized by XRD, N2 sorption, TEM and UV–Vis. The acidity property of acidic sites in the surface of the samples was investigated by pyridine-absorbed FT-IR. The results indicate that the materials exhibit high surface area and uniform pore distribution. The samples contain both Lewis and Brönsted acid sites, moreover, the total concentration of both Lewis and Brönsted acid sites increases with the decrease of the ratio of Si to Sn. And Lewis acid site plays the dominate role. more...

This study introduces a method of ammonia nitrogen removal from chlor-alkali industry wastewater by magnesium ammonium phosphate (MAP) precipitation. The effect of pH, reagent ratio and temperature were investigated. The pH was found to be the most significant factor. The optimal ammonia nitrogen removal ratio is about 46% under the condition of pH=10, reagent ratio n(Mg) : n(N) : n(P)=1.2 : 1.0 : 1.0 and temperature=35°C. According to this study, MAP precipitation method has the potential ability to be applied to remove ammonia nitrogen from chlor-alkali chemical industry wastewater. more...

The aim of this study was to investigate the effect of the catfish bone hydrolysate (CBH) on morphology of bacteria which were observed by atomic force microscope (AFM) and transmission electron microscope (TEM). The CBH was found to inhibit Escherichia coli (E. coli) growth. The CBH at 10 mg/ml caused the significant fragmentariness in the bacterial membrane and a severe volume decrease. A possible mechanism is that CBH damages the structure of bacterial cell membrane which causes E. coli bacteria to die eventually. more...

Whatever types of batteries, when they work out of the normal temperature range, their performances greatly worsen. When the battery charges or discharges in a high rate, it would be quite possible to arouse thermal runaway had the heat generated not dissipated properly. This article commits itself to take the variation of the battery internal resistance into account to revise the overall temperature rising curve based on a simplified battery thermal model. By carrying out necessary experiments and using CFD simulation tool we get a better battery temperature rising curve and contour of internal temperature distribution under different operating conditions. It is applicable to provide reference for the thermal management of power batteries. more...

A fixed-bed experimental apparatus with the capacity of 1kg coal was set up for coal pyrolysis by solid heat carrier. Shenmu bituminous coal and quartz sand was used as raw material and solid heat carrier respectively. The effects of initial temperature of solid heat carrier, reaction time and blending ratio on the yield of gas and tar were examined at different conditions. The results showed that tar yield was above 10 wt% when the initial temperature of solid heat carrier more than 800oC, reaction time and blend ratio had lesser influence on gas and tar yield. At the investigated test condition, smaller coal particle leads to an inconspicuous increase on gas and tar yield. The characteristic of gas and tar products was also investigated in this paper. more...

Northwest China is rich of coal energy. Mining activities bring serous impact on the environment and scarce water resources because of its shallow buried and severe mining impact. Stowing mining is one of the most effective measures to control strata movement and reduce surface subsidence. Based on the local surface widespread wind-blown sand for aggregate and combined with the knife pillar mining，this paper introduces the stowing mining technology. more...

Most popular agents for protein cleavage are proteolytic enzymes, but they require more rigorous hydrolytic conditions, and it is very difficulty to separate them from the productions. In this paper, an new artificial metalloprotease, Cu(II) complex of cyclen (Cu(II)Cyc) using chitosan as supporter, was designed and synthesized successfully. The hydrolytic efficient under different conditions was measured and confirmed with HPLC, SDS-PAGE, further more. Some reaction conditions, such as pH, temperature, were researched, and the results show that the optimum reaction time was 48 h, temperature was 60 °C respectively, The observed rate constants for trypsase inhibitor cleavage was 1.006×10-2 h-1 under above conditions, and the observed rate constants was 2.120×10-2 h-1 when the pH was 9.0. This paper suggested that the chitosan metal complexes could efficiently accelerate the hydrolysis reaction. more...

Using crack to evaluate the bearing capacity of RC Beam Bridge is an effective method. This paper puts forward using the crack spacing, width, height and their statistical weights to characterize the structural crack index and using Analytical Hierarchy Process to get crack index expression. After a lot of survey analysis of actual cracks, get corresponding relation between crack index and the checking coefficient of their bearing capacity, then through structure resistance expression to check structure, finally the assessment of the bearing capacity of the bridge was got. With a simply supported T beam bridge as an example, the result shows that this method is reliable, simple and economical. more...

With the development of the simulative theory and calculation method of drainage pipe network, urban drainage pipe network model gradually become an indispensable part of the urban drainage system management. The characteristics of modern drainage pipelines,the content of drainage pipelines system model, the problems of combining GIS with drainage pipelines and how to solve them are briefly described in this paper. more...

This paper first provides some context for understanding the Japanese and Chinese venture capital industry. Then it set forth an evolution of venture capital. The heart of the paper is devoted to a discussion of the key features of Japanese and Chinese venture capital. This includes information concerning the size of the industry, the players, and the nature of the venture capital investment. This is followed by an analysis of the comparison of Japanese and Chinese venture capital industry. more...

The flow behavior of a 7039 aluminum alloy and the corresponding microstructural evolution during hot deformation were studied by Gleeble-1500 thermal simulation tests, EBSD and TEM observations with temperatures ranging from 300 °C to 500 °C under strain rates from 0.01 s-1 to 10 s-1. It has been shown that the flow stress increases with the decrease in the deformation temperature and increase in the strain rate. The degree of dynamic recrystallization (DRX) increases with the increase in the deformation temperature and strain rate in 7039 aluminum alloy. The complete dynamic recrystallization occurs at 500 °C with a strain rate of 10 s-1. more...

In order to discuss the mechanical behaviour differences between the two-tower and three-tower suspension bridges, based on the Taizhou Yangtze River Bridge, three dimensional space finite element models of two-tower, three-tower with concrete mid-tower and with steel mid-tower were constructed. Through the comprehensive analysis, main conclusions are got as follows: due to the mid-tower lack of effective restraint from side cable, compared with two-tower suspension bridges, three-tower suspension bridges have lower total stiffness and natural frequency, with larger deflection-to-span ratio of main girder. So, some factors such as anti-slipping safety factor between the main cable and saddle, deflection-to-span ratio of main girder and force in mid-tower, which are not important in two-tower design, become controlling ones in three-tower suspension bridges. These factors are related to anti-pushing rigidity of mid-tower, but in contradictory demanding for the rigidity of mid-tower. After comprehensive analysis, steel tower with shape of upside-down ‘Y’ meets all demands, and then, was selected as appropriate structure for the mid-tower. more...

Mechanical behaviours of three-tower suspension bridges from perspective of influence line help insight into mechanical behaviour nature, and grasp the differences between two-tower and three-tower suspension bridges in Static and dynamic behaviours. Based on the Taizhou Yangtze River Bridge, three dimensional space finite element models of two-tower, three-tower with floating system and three-tower with elastic cables between mid-tower and the girder were constructed. Through analysis of influence lines characteristics of different key effects and effect envelop under vehicular load, main conclusions are got as follows: Some factors such as deflection-to-span ratio of girder, anti-slipping safety factor between the main cable and saddle of the mid-tower and force in the mid-tower, horizontal displacement at the end of girder, which are not important in two-tower design, become controlling ones in three-tower suspension bridges and effects under vehicular load is the most important. When live load acts on all or part of one main span, the four control factors reach the worst case, but in very low probability. Code restriction on deflection-to-span ratio of girder can be flexible to relax restriction to 1/220, and riding comfort is still guaranteed. Stresses of mid-tower under vehicular load plus dead load are in a state of compressive stress in the majority of operating conditions and fatigue problem is not obvious. more...

Competitive adsorption experiment of fluoride and phosphate on MgAl-CO3 LDHs has been conducted. A series of batch experiments were performed to study the influence of various experimental parameters such as pH, adsorbent dosage and contact time on the adsorption of fluoride and phosphate on MgAl-CO3 LDHs. Three kinetic models have been evaluated in order to attempt to fit the experimental data, namely the pseudo-first order, the pseudo-second order and the Weber and Morris intraparticle diffusion model. The effects of the initial concentration and the addition order of fluoride and phosphate on their adsorption by MgAl-CO3 LDHs were also investigated. The results show that the optimal pH is 4 to 5, adsorbent dosage is 2 g/L and it takes about 2 hours to attain equilibrium. It was found that the pseudo-second order most closely describes the kinetics. The initial concentration and the addition order of fluoride and phosphate influence the adsorption of fluoride to a certain extent, but they have relatively small influence to the adsorption of phosphate on MgAl-CO3 LDHs. more...

The ability of Cr-bentonite prepared using synthetic wastewater containing chromium was investigated for adsorptive removal of 4-aminophenol and 4-chlorophenol from aqueous solution in a batch system at 25 °C. The physic-chemical parameters including pH value of solution and contact time were studied. The experimental data were analyzed by the Langmuir, Freundlich and Temkin models of sorption. The equilibrium sorption data for 4-aminophenol and 4-chlorophenol were well fitted to Langmuir adsorption isotherm and the monolayer sorption capacity was found to be 26.53 and 23.81 mg/g at 25 °C, respectively. The sorption energy calculated from Dubinin-Redushkevich (D-R) isotherm are 8.31 and 8.20 kJ/mol for the uptake of 4-aminophenol and 4-chlorophenol respectively which indicates that both the sorption processes are chemical in nature. The kinetic data were analyzed using pseudo-first order, pseudo-second order kinetic equation and intraparticle diffusion model. The experimental data fit very well the pseudo-second order kinetic model. Intraparticle diffusion affects 4-aminophenol and 4-chlorophenol uptake. Sorption studies carried out using industrial wastewater samples containing phenolic compounds show that there is significant potential for Cr-bentonite as an adsorbent material for phenollic compounds removal from aqueous solutions. more...

To show that taking measures can bring benefits in marine pollution, first of all, we compared the added weight of polystyrene containers debris between taking and not taking the “3-Cent –measure”. Besides, we calculated the cost for taking this measure. On the bases of these, we found the benefits of taking measures are far greater than their costs. Finally, we suggest that the government take long-term interests into account, and take measures to treat marine pollution. more...