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Three dimensional finite element models of composite joints were established to investigate the load-displacement behavior, failure mode of multi-axial tubular joints under bending load, and stress-strain relationship in some key positions. The joints were prepared by plain weave fabric. The effective elastic constants of fabric composite were calculated using meso-mechanics theory. A progressive failure analysis was performed using ABAQUS software to obtain the ultimate strength and failure mode of the sample. In addition, the damage process, failure mode and damage position was further studied. The bending properties of the joints were also presented by quasi-static load test using a three-point bending test device. Results of the ultimate load and damage analyses are compared to experimental data. The accuracy of the method was proved by the consistency of the relation between the load displacement curve trend and the correlation of the damage position and failure pattern.

Demand for copper is growing in the world,which makes it increasingly necessary to process low-grade ores and tailings that used to be considered as wastes. The development and application of bioleaching by acidophilic chemolithotrophic microorganisms, which obtain energy from the oxidation of sulfide minerals and use carbon dioxide for constructive metabolism, has been a major approach for processing the low-grade copper ores. In this study, mixed culture consisted of six iron and sulfur oxidizing microorganisms were used in leaching of flotation and acid-leaching tailings obtained from Zambia sulfide ores. The result showed that 62.7% and 61.7% copper were dissolved by bioleaching, while 53.8% and 57.4% by acid leaching in flotation and acid leaching tailings, respectively. In addition, mineralogical forms of copper were quite noteworthy since copper sulfide mineral extraction was significantly improved in bioleaching. XRD analysis showed wollastonite and diopside in acid tailing were undetectable after 23 days while others were difficult to be dissolved. No jarosite or sulphur was detected by XRD in residues.

In order to investigate the effect of initial proportions of microorganisms on chalcopyrite leaching, six typical bioleaching strains were used to rebuild different co-culture systems. According to their different energy use types, Acidithiobacillus ferrooxidans DX2012 (ferrous and sulfur), Sulfobacillus thermosulfidooxidnas DX2012 (ferrous and sulfur), Leptospirillum ferriphilum DX12 (only ferrous), Ferroplasma thermophilum L1 (only ferrous), Acidithiobacillus caldus DX2012 (only sulfur), Acidithiobacillus thiooxidans A01 (only sulfur) were classified to construct four groups(cells): a, 1:1:1:1:1:1; b, 10:10:1:1:1:1; c, 1:1:10:10:1:1; d, 1:1:1:1:10:10. The results showed that leachate pH of consortium a, d firstly began to decline until stabilized at 1.4. On day 9th, Eh of consortium d began to sharply rise and finally stabilized at 720 mV. Compared with consortium a, b and c, copper concentration of consortium d increased to the highest level of 6000mg/L. All the evidence suggests consortium d is the best combination which held the highest leaching rate of copper. Real-time quantification polymerase chain reaction (RT-qPCR) was used to analyze the population dynamics during all the bioleaching process. Final microbial community structure of four consortia was trended roughly the same and consortium d was first to reach final community structure on day 27th. It is concluded that bioleaching co-culture system containing a higher proportion of sulfur-oxidizing bacteria works more efficiently.

The column chemical leaching and bioleaching methods recovery of uranium from one uranium ore containing brannerite under the some conditons were investigated. The brannerite ore sample taken from one uranium mine in southern China, the ore particle size was crushed to -5mm, the uranium content is 0.281%. The leaching duration lasted 120 days, the acid consumption rate were 7.82% and 7.79% by ore weight, the slag uranium leaching rate were 89.32% and 91.46% that calculated by its residue has been recovered. This work has indicated that column bioleaching can enhance 2.14% uranium recovery percentage than chemical oxidation leaching, bioleaching be the promising method for uranium extraction from refractory brannerite ore in the deposit.

Iron oxidized acidophlies are important in uranium extraction for it mainly depends on the indirect mechanism of bioleaching. Taking indirect field In-Situ bioleaching experiment in a uranium deposit as an example, several strains of acidophiles were isolated from the acid leachate. Bacteria compositions of the samples taken different stages were analyzed by 16SrDNA PCR-RFLP method. Results showed that the dominant bacteria in the leachate were Acidithiobacillus. ferrivorans, At. ferrooxidans and Leptospirrilum. ferrooxidans from the beginning to the middle stage of bioleaching process. With the process carried on, ferric ion concentration increased in the oxidation tanks, L. ferrooxidans became predominant bacteria. Again confirmed that in this in-situ bioleaching site, iron oxidized bacteria were in dominant.

In the bioleaching process, many factors in ore, water and sediments are important contributors as driving forces to improve leaching efficiency. In this study, FeSO4·7H2O and S0 as energy substrates were added to an oxide-rich, low-grade copper ore to explore the influence of biological and environmental factors on leaching efficiency. Mantel test results showed that the leaching rate was significantly correlated with biological and environmental factors with r values of 0.78 and 0.63 respectively, indicating that influence of biological factors were more significant. It cannot be ignored that environmental factors were important to construct the microbial community. Real-time quantification polymerase chain reaction (RT-qPCR) showed that the dominant and minor species were A. caldus and A. ferrooxidans. Canonical correspondence analysis (CCA) made it clear that pH and ferrous concentration were crucial for shaping microbial community. All results are of great significant to gain the optimal leaching condition on Zambia oxide-rich, low-grade copper ore.

The draft genome of newly isolated Acidithiobacillus ferrivorans ZB-1 and DX-1 were deciphered to obtain a comprehensive insight into the genetic information and to discover the cellular mechanisms during its high activity in low temperature environment. Genome analysis speculated that Acidithiobacillus ferrivorans ZB-1 and DX-1 could fix carbon dioxide through the Calvin cycle and other central carbon metabolism potentially, and may be able to absorb and utilize nitrate or nitrite in the environment. The related cryophylactic genes (CspD, CspE, Fad and FabG) and gene clusters in fatty acid synthesis were discovered and suggested to play a crucial role in cold resistance.

With the rapid development of construction, the high quality of the construction material is required. Mixing carbon fiber in concrete attracts more and more attention as it can reinforce concrete. However, the science research and engineering application of carbon fiber reinforced concrete is relatively few. In this paper, the effects of different mixing amount of carbon fiber and the sand ratio in concrete and the curing time of concrete and relationships between these factors were investigated. Proper carbon fiber and sand ratio can promote the compressive strength of concrete and it has a good resistance to cracking. The compressive strength of concrete with different mixing amounts of carbon fiber peaks when the sand ratio was 31% and the compressive strength was better when the carbon fiber mixing amount was 0.2% and 1% than any other ratios after 28 days. When the sand ratio was 31%, the compressive strength of carbon fiber mixing amount increased with the increase of curing time and it reached the top when the carbon fiber ratio was 0.8%. The mixing amount of carbon fiber also had a great influence on the early compressive strength to some extent. We anticipate that the research can offer certain reference for engineering practice.

The AlN nucleation layer (NL) has been deposited on Si (111) substrate by metal-organic chemical vapor deposition (MOCVD). The result indicates that the growth mode of the AlN NL is in the form of 2-dimensional plane and 3-dimensional island. The proportion of 3-dimensional region increases gradually and the 2-dimensional region reduces correspondingly with the increase of growth time. The decrease of the coverage ratio of AlN grains in the 2-dimensional growth region is due to the effect of etching. AlN film with the single crystal orientation has been deposited on the optimized AlN NL.

With lanthanum chloride solution as raw material, and use the hydrogen peroxide of clean and pollution-freeobtained from oxidation reaction as auxiliary reagent, and with the carrier gas together form spray pyrolysis to obtain lanthanum oxide. On the one hand, in the hydrogen peroxide system, the temperature of direct pyrolysis reaction of lanthanum chloride solution decreased obviously, The reaction temperature is decreased from 1280°C to 1000°C or less. That reduce the energy consumption and simplify the requirements of pyrolysis equipment technology. The production process does not use NH3.H2O and NaOH to precipitate. It does not produce the traditional process of NH4+, Na+ to pollute water. It can greatly reduce the damage to the environment, and can product with high yield, high purity of the rare earth oxide. This method not only applies to the pyrolysis of the rare earth chloride solution, also applies to metal chloride solution, such as FeCl3, AlCl3, NiCl2. It was shown that the reaction temperature has been effectively reduced, VLaCl3: VH2O2 with 1: 1.5 can get high purity of La2O3.

A facile biomimetic method was developed to enhance the interfacial interaction in organic-inorganic hybrid materials. By mimicking mussel adhesive proteins, a monolayer of polydopamine (PD) was constructed on surface of Al (OH)3 particles through a controllable coating pathway. The modified Al (OH)3 (PD-Al (OH)3) was incorporated into an epoxy resin. It is found that the strong interfacial interactions brought by the polydopamine benefits the effective interfacial stress transfer, leading to greatly improved flexural properties of the organic-inorganic hybrid resin.

Aiming at power plants denitrification system existing chimney entrance NOx concentration than denitrification system outlet NOx concentration of "upside down" phenomenon, adjust and optimize the test denitrification system, denitrification system NOx concentration distribution uniformity can be obviously improved after the adjustment, improve economy of denitration system operation. At the same time, the denitrification system operation suggestion.

Emissions of air pollutants from coal-fired power plants pose a threat to healthy living environment. Developing renewable energy and changing electricity generation structure dominated by coal-fired power has become a vital national strategy. In this paper, taking a rapidly urbanizing coastal area in southern Laizhou Bay of China as the study area, a scenario planning concerning substitution of wind power for coal-fired power in enterprise-owned power plants was conducted. Coupled with the electricity generation prediction by a grey prediction model GM (1, 1) and the calculation of pollutant emission intensity, we obtained three scenario schemes: no substitution (Scenario 1), low substitution (Scenario 2) and high substitution (Scenario 3). The results showed that Scenario 1 is not acceptable; Scenario2 is acceptable, but not ideal; Scenario 3 is optimal. The electricity generation structure under Scenario 3 has been radically converted from the type dominated by fossil fuel to one dominated by renewable energy, becoming an environment-friendly power generation framework with fairly low pollutant emission densities. This study can contribute to local managers to seek more concrete measures in mitigating the conflict between electricity demand and environmental health.

Three kinds of porous materials were synthesized using calcined kaolin with small molecular amine templates by hydrothermal methods. Sodium silicate was chose as silicon sources and three different amines namely acetamide, ethylenediamine and hexamethylenetetramine were chose as the organic templates. The physicochemical properties of obtained samples were characterized by X-ray diffraction, infrared spectrum and scanning electron microscopy.Crystallinity and morphology of samples were investigated. The influence of small molecular amines templates was discussed.

Based on the characteristics of the geometric control method during the construction of cable-stayed bridge, the key goal to complete the bridge is to ensure that the non-stress dimensions and profile of every component is constant. Because one of the key points to complete the cable-stayed bridge is to ensure that the non-stress length of the closure segments is constant, it is necessary to adjust the relative position of the final closure by the geometric closure method of incremental launching construction to satisfy the requirement of the non-stress length of the closure segments. Aimed at the critical technical problems existing in incremental launching construction process, taking Jiashao bridge as the research subject, the analysis of the incremental launching plan and the local stress of pushing bracket and bearing block are carried out. The research will provide scientific basis for the feasibility of geometric control incremental launching construction method and it will guarantee the smoothly incremental launching construction.

A facile biomimetic method was developed to enhance the interfacial interaction in polymer-inorganic composites. By mimicking mussel adhesive proteins, a monolayer of polydopamine (PD) was constructed on surface of silica particles through a controllable coating pathway. The modified silica (PD-silica) was incorporated into an epoxy resin. It is found that the strong interfacial interactions brought by the polydopamine benefits the effective interfacial stress transfer, leading to greatly improved flexural properties of epoxy based composites.

A series of hybrid membranes with special microstructure, based on sulfonated poly (fluorenyl ether ketone) ionomer (SPFEK, IEC=1.74 mequiv.g-1) and secondary amine group containing SiO2 (SiO2–NH–NH2), has been successfully designed and prepared for vanadium redox flow battery (VRB) application. The hybrid membranes are prepared by simply adding KH792 into the SPFEK solution in N,N’-dimethylacetamide (DMAc), followed by dispersion, co-condensation and solvent casting. The water uptake, mechanical property, proton conductivity, (VO)2+ permeability and single cell performance are investigated in order to understand the relationship between morphology and property of the membranes. The hybrid membranes show dramatically improved proton selectivity when compared with SPFEK. The vanadium ion (VO)2+ permeability through the hybrid membrane is about 10 times lower than that of virgin SPFEK. The columbic efficiency and energy efficiency of the single cell of the hybrid membrane are higher than the SPFEK membrane. The results inidicate that hybrid membranes of this type are promising for VRBs.

First, behavior models of the station operator and consumer are established considering all the main factors. Second, an optimized EV charging pricing method using Game Theory is introduced based on benefit-cost analysis. The calculation of government subsidies is also proposed in order to reach an equilibrium charging price. Finally, actual data of Hebei is used and results are shown to give supports to local government and charging station operator’s decision making.

Along with the increasing use of cables in power grid and the increasing ration of distributed power sources’ synchronization, such as small hydropower’s synchronization, increasing the reactive power transmission on the line, make it difficult to achieve the balance of reactive hierarchical partition. Take a certain region’s power grid for actual examples, after the installation of magnetic control reactor (MCR), using immune genetic algorithm (IGA) to coordinate the capacity of magnetic control reactor and the existing reactive power resources, the results show that the magnetic control reactor does much good to absorb the system’s excessive reactive power and limit the voltage’s increasing.

The quality of the kaolin is always measured by iron contents since this element gives undesirable reddish color which limits the usage of this type of minerals. Reducing the iron contents to increase the value of kaolin by bleaching process is investigated. The effects of factors which can improve the whiteness of kaolin have been studied. The dosage of sodium dithionite, pH value, solid-to-liquid ratio and reaction time were chose as factors based on mono-factor experimental results. Orthogonal experiments were carried out and the optimum processing conditions of the reductive bleaching were obtained as the dosage of sodium dithionite 3%, pH 2, solid-to-liquid ratio 1:3 and reaction time 45min. After bleaching process described above, we obtained a great improvement in the whiteness from 69.93% to 81.31% and a decrease of Fe2O3 content from 0.52% to 0.40% of the kaolin.

The effect of slag treatment with Copper addition in silicon purification by metallurgical methods was examined in this paper. The microstructures and contents of Si-Cu alloy after slag refining were investigated by XRD and ICP, respectively. The majority phases in the Si-Cu alloy were Cu3Si and Si. The partition ratio of boron (LB) between slag and silicon was studied with and without Cu addition. Experimental results show that slag treatment with Cu addition can improve the LB in CaO-SiO2-CaF2 slag system, where a maximum boron removal ratio of 85% could be achieved.

The world is facing energy crisis and the search for renewable bio-energy is currently one of the most important issues. Energy plant as a kind of bio-energy feedstock has attracted more and more attention, especially its planting issue. Short rotation coppice (SRC) is used as a proxy for other energy plants. This paper investigates farmers’ planting decisions of SRC under the threat of regulatory taking which is rarely mentioned in the previous relevant literatures. We use real options approach and especially take the risk of regulatory taking into account to analyze whether or not to grow SRC instead of traditional crops on farmland. It turned out that the threat of regulatory taking reduces the investment threshold and stimulates farmers to grow SRC. In other words, the threat has potential to improve the development of bio-energy.

In order to reduce the emission of CO2 and control the global greenhouse effect, the paper introduces and compares two new technologies named chemical-looping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU) that are both high-efficient and clean. Through comparative analysis, CLC has been widely studied because of its direct separation of CO2, reduction loss of the heat, improvement of energy efficiency and avoiding of the generation of fuel type NOx in the combustion process. Besides the current research for metal oxygen carrier, there are some scholars find various non-metal oxygen carriers that have the better performance in CLC. But the study on reactors of CLC is still not mature, especially the solid fuel reactor, which is different from CLOU. In a certain sense, CLOU is an improved technology based CLC, besides the bove advantages, it also can react with coal directly. Many scholars use coal as fuel in the fluidized bed by the technology of CLOU, and the results of them are feasible. So from this perspective, CLOU technology has more broad prospects than CLC in the China.

Compared to other desulfurization technologies, aerodynamic emulsification technology has obvious advantages among the whole flue gas desulfurization technologies. This paper describes the characteristics of aerodynamic emulsification technology from the perspectives of the technical and economic, and affirms its development and application in the recycling lead industry with examples, while denying use desulfurization equipment of Italy in China.

Iron titanate photocatalysts were synthesized by the high-energy ball milling method with titanium ore as the starting material. X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), thermal gravity and differential thermal analysis (TG-DTA), UV-visible diffuse reflectance absorption spectra (UV-Vis), photoluminescence emission spectra (PL) and photocatalytic degradation measurement were conducted to characterize the structure, surface status, UV-visible light response and performance of the obtained sample. After low temperature calcination (above 400 oC), the photocatalytic activity of iron titanate catalyst decreased gradually, which was mainly due to the decrease of surface hydroxyls and reactant adsorption capability.

The masonry building takes a majority of town housings in these areas. Unlike the experimental study, the Finite Element Analysis is an important part for better comprehension of the finite element method and can reduce the investment and manpower. The aim of this paper is to simulate the structural response from the variety of masonry buildings under earthquake excitations by using finite element software called ABAQUS. There are four models of the masonry building with different storey, which include the one without constructional column and ring beam, with constructional column only, with ring beam only and with constructional column and ring beam simultaneously. In the process of modeling, we adopt the integrated model and regard walls, constructional columns, slabs and steels as homogenous continuums. Furthermore, we adopt concrete damaged plasticity material model to simulate the material of building and input El Centro earthquake wave N-S component. The result of analysis shows that setting ring beams or constructional columns can significantly improve the integrity of the building and reduce the mises stress on foundation. The result of analysis has a significant guidance on masonry building construction in seismic region.

To accurately calculate the prestress of externally prestressed composite girder bridges, the six critical factors (the prestressing tendon withdrawal and anchor deformation, friction between prestressing tendon and deviator, prestressing tendon relaxation, concrete creep, concrete shrinkage and temperature changes) that cause the prestress loss of such type of the bridges are summarized and the corresponding simplified calculation methods are respectively derived on the basis of the existing researches. The prestressing tendons ability has an important influence on the mechanical behavior of prestressed composite girder bridges, which is the key design parameters. Prestress loss will occur in the process of long-term use, so that the whole beam stress redistribution occurs. How to accurately calculate the value of the prestressing loss is an issue of great concern to engineers. And at present there is few research for prestressed composite girder bridges. On the basis of existing research, this paper summarizes the key factors that lead to loss of prestress and derives the corresponding simplified calculation method for design reference.

In the construction process of Hong Kong-Zhuhai-Macao Bridge, the side span girder of Qingzhou channel bridge, the non-navigable span of the shallow water region and the side span S11 ~ S17 large segments are located between transitional pier and auxiliary pier of Jiuzhou channel bridge are based on the large segment hoisting construction technique. The widely use of the large segment hoisting construction which can ensure the construction safety and shorten the construction period obviously, effectively reduce the bad environment factors in construction. All of these are important to the transportation hub, Hong Kong-Zhuhai-Macao Bridge. But because of the transformation of structural system and the complex stress of the large segment girder in the lifting point in transportation and hoisting process, it is significant to do the finite element simulation analysis.

Realistic prediction of concrete creep is of crucial importance for the safety, durability and long term serviceability of concrete structures. High performance concrete (HPC) contains combinations of various components, such as aggregate, cement, water-reducing agent and other ingredients which affect the properties of the HPC including creep. This paper reviews the accuracy of the conventional concrete (CC) creep prediction models, including B3,GL2000 and CEB-FIP(2010). Further, a new creep prediction model based on the comprehensive analysis is proposed. The improved model was calibrated through a joint optimization of laboratory creep tests. Comparisons of the results of the proposed methold with 76 data points of creep coefficient showes good agreement.

An in depth state-of-art review is done on the topic, constitutive relations of masonry under compression. 12 constitutive models of masonry proposed by scholars from home and abroad are presented in the paper. These models can be classified into four types. Merits and drawbacks of each constitutive relation are discussed. Ten typical constitutive relations are selected to make comparisons. Results show that the ascending branch of curves has few differences, major differences occur in the descending branch of curves. Besides, two experimental data are used to analyze the models and results are discussed. Furthermore, some suggestions on this topic in future research are presented.

In order to improve dynamic and static performance of the precision horizontal machining center, the method of multi-objective optimization based on the response surface model was applied for optimizing design of the bed structure. The design variables were the layout parameters of the rib plates. Sample points were obtained by the Box-Behnken design experiment, and responses of sample points were analyzed by SAMCEF. The maximum deformation of guide rails and the low-order natural frequency were extracted to fit the response surface model by least square method. The layout parameters of the rib plates were optimized through the application of multi-objective genetic algorithms. Then, relationship between the lightening holes and the performance were analyzed to determine the suitable diameter. The results verify the validity of the optimization method, and the paper provides methodological guidance for optimization of machine tool structural parts.

Seedlings of Michelia macclurei, Cinnamomum camphora, Rhodoleia championii and Mytilaria laosensis were placed in open-top chambers (OTC) with three ozonic treatments including E20 (20 ppb), E40 (nature air, 40 ppb) and E160 (160 ppb) and two water treatments. Root biomass, stem biomass and leaf biomass total biomass and root/shoot ratio of four seedling types were evaluated. The results showed that there were no significant differences in impacts of ozone stress and drought stress on root, stem, leaf, and total biomass of M. macclurei among different treatments. The biomass of M. laosensis decreased with increasing ozone concentration, whereas biomass of C. camphora and R. championii changed irregularly. Most of the biomass of four kind seedlings under ozone and drought intercross stresses was lower than those under ozone stress. The root/shoot ratios of four seedling species were all low. The ratios under high concentration ozone (160 ppb) were lower than the control treatment. And the ratios of different treatments under drought were lower than those were not under drought when they were under the same concentration of ozone.

The polysaccharides were isolated from the abalone Haliotis discus hannai Ino cultivated from Qingdao and Fujian, and their proliferation activity on HepG2 cell was assessed. The monosaccharide composition of the abalone polysaccharides from Qingdao and Fujian was different, which might be related to their different geographical location and breeding conditions. The proliferation activity of abalone polysaccharide from Qingdao was better than that from Fujian. AAP, AVAP I and AVAP II were further isolated from the abalone polysaccharide from Qingdao, the cell proliferation activity of AVAP I and AVAP II was better than AAP, which might be depended on their monosaccharide composition. Our study would provide preliminary data for the high value utilization of abalone polysaccharides.

As we all know that the key problems of logistics finance are risk aversion. In order to strengthen the practicality of logistics finance, the paper adopts three-dimensional stereogram to analyse nine risks of logistics finance. In order to minimize these risks, RFID and other Internet technologies are applied to design the visual impact of approach for reducing the risks, when the information among stakeholders is not fully shared.

To avoid the problem of mutual interference of moving parts and errors of assembly appears in the prototype design stage, this article is based on virtual design idea, a small snow removal vehicle has been designed based on virtual design idea, using pro/e 3 d modeling software in this paper. 3 d modes of parts of the small snow removal vehicle and virtual assembly have been completed. The mall snow removal vehicle has a throw snow impeller, a built-in worm gear reducer and a helix-collect snow set. The motion simulation has been operated. The design of the small snow removal vehicle is right according to the studying of virtual assembly and motion simulation.

In this paper, the history and present conditions of welding robot were summarized in domestic situation and foreign situation, the latest development in technology was discussed. According to the structure and motion features of welding robots, using the UG simulation techniques can help us to establish the virtual prototype model of the robot easily, which can achieve the movement of the whole system analysis, dynamic analysis and so on. In this paper, the result of the application ADAMS simulation software is that the simulation mode provide reference for optimize the structure and drive mode design. It also was provided a possible scheme for the final optimal design.

Gas is an important secondary energy in integrated iron and steel works. In this paper we proposed the reasons for low gas utilization by analyzing the characteristics and recycling situation of gas resource. One is the relatively backward idea, the other is that the ways and means of optimizing gas utilization are also backward, then we come up with the countermeasures to improve gas resource utilization. First of all we should promote energy conservation of enterprise system, optimize comprehensive utilization of gas and improve the energy structure. Second is putting more investment in new technology development and take active use of new technology and new process, such as high temperature air combustion technology, combined cycle power plant technology, enriched technology of blast furnace gas and so on. Last is developing gas deep processing to promote co-products of steel and chemical industry. The high added-value chemical products can be obtained by technologies such as production of hydrogen and methyl alcohol with coke oven gas, synthesis of methanol and dimethyl ether with converter gas and so on.

Drawing speed is one important process in production over-head line, deform 3d software is used to simulate the drawing process. The distribution of stress-strain and temperature in different drawing speed with die angle and friction coefficient was investigated. The results shows that the aluminum conductors can be used in high speed drawing when die angle, drawing speed and frication coefficient of first pass is about11~13 degrees, 4~6m/s and 0.08~0.10 respectively, the uniformity of stress-strain and temperature is better for producing good quality over-head wires with high cold-drawing speed.

Xiangshan uranium deposit is the largest volcanic rock type uranium ore in China. Great number of low grade uranium ore (U < 0.03%) was stacked in the tailings dam as a waste rock in more than 50 years of exploitation, resulted in uranium resources waste. Two group column bioleaching experiments (column AB) were carried on in order to investigate uranium recovery effect by microbial for the low grade uranium ore. The bacteria for the tests was a mixture mainly composed by Acidithobacullus ferrooxidans and Leptospirrillum ferriphilum, which was isolated from the uranium minerals of Xiangshan uranium deposit and domesticated with the mineral and leachate system. The average uranium content is 0.0123%, the particle sizes for column A and B is less than 25mm The Fe2+, Fe3+ and F- average contents of the test minerals were 1.90%, 0.59% and 0.14% respectively. Results showed that uranium leaching rate calculated by uranium concentration of slag were 76.75%, 75.31% in 95days and 85 days of test column A, B respectively. Rate of acid consumption of column test A, B were 7.60% and 7.69% respectively. while the rate of acid consumption was usually more than 10% by acid leaching. These evidences suggested that microbial hydrometallurgical technology was had effective for the low grade uranium ore and significant on uranium recovery for the low grade uranium ores.

The leaching heap and acid mine drainage are two key nodes in a bioleaching system. This study aimed to investigate the microbial community structural and functional diversity between the two nodes in bioleaching system from Dexing copper mine in Jiangxi province, China. 16SrRNA gene cloning and metagenomic analysis consistently indicated that there were obvious differences on microbial community structural and functional diversity in the two nodes. In leaching heap, the dominant species was the heterotrophic bacterium Acidiphilium; while the dominant species was the autotrophic bacterium Acidithiobacillus in acid mine drainage. Seven bacteria species were found in both two nodes, while the unique bacteria species in leaching heap and acid mine drainage were eleven and eight, respectively. In relation to the microbial community function aspect, all contigs and singlets were annotated against the non-redundant protein database of NCBI and clustering analyzed with COG database. For the two nodes, the COG clustering results showed that the functional category abundances were different, though the functional categories were similar. And the great majority of ORFs were forecasted as function unknown. All the results meant that the microbial community structural and functional diversity of bioleaching system was not as simple as former thought. This study could provide a new meta-view of theoretical support to bioleaching process.

The mechanical properties, including the compressive strength, flexural strength and adhesion strength of the rapid setting conventional and polymer-modified waterproof mortars are systematically compared in this paper. The polymer modification is demonstrated to increase the flexural strength and adhesion strength of the rapid setting waterproof mortar whereas it reduces its compressive strength.

To improve the oxidation resistance and insulation of tungsten electronic device at high temperature, an AlPO4/Al2O3 composite coating was synthesized on the tungsten substrate by sol-gel method. The morphology of coating was investigated by scanning electron microscopy (SEM). Compared to the blank specimens, the coated ones exhibit excellent oxidation resistance and insulation at about 1100, which can be attributed to the compact coating without porosity and crack. Up to 1200, the effects of coating became dramatically poor. The electron conductivity mechanism was discussed.

A new unsymmetrical diarylethene derivative 1-(1, 5-dimethyl-2-pyrrolecarbonitrile) -2-[2-methyl-5-(4-aminomethyl) phenyl-3-thienyl] perfluorocyclopentene (1o) was designed and constructed successfully. Its optoelectronic properties have been discussed systematically, such as photochromic, kinetics experiments in acetonitrile solution and PMMA.

Type-I clathrates have been considered as very promising thermoelectric (TE) materials thus attracting attention widely. Here we report new clathrates Ba8CuxSiyGe46-x-y (4≤ x ≤ 6.5, y = 0 and 5.15 ≤ x ≤ 6.425, 2.05≤ y ≤ 36.9), focusing on their phase purity and TE properties. Our results show that samples prepared by arc melting followed by annealing are multi-phases alloys. The composition of the clathrate phase is also inhomogeneous. This indicates that the kinetic factor dominates the reaction of forming the clathrate phase during element-melting and sample-annealing. We select three compositions in these two series of samples, which have less impurity and better composition homogeneity for the clathrate phase, and the annealed alloys are furthered processed by ball milling (BM) and powder-solidification (either by hot pressing (HP) or by spark plasma sintering (SPS)) for TE properties investigations. The BM and HP/SPS processes can improve the phase purity and homogeneity. The TE measurements show that the Si-substituted samples have better performance than the Ge-based sample, mainly by decreasing the electrical resistivity. This indicates that the elemental substitution may be still an effective way to improve the TE performance of clathrates.

Perturbation method is used to resolve one-dimensional wave equation under the assumption of small strain conditions. The relationship of the second order relative nonlinear coefficients (SORNC) β', the third order relative nonlinear coefficient (TORNC) δ' as the functions of fundamental and harmonic amplitudes is determined. The specimens are loaded from-200 MPa to 320 MPa at increments of 40 MPa by the electron universal testing machines. The SORNC β' and TORNC δ' are detected by the nonlinear ultrasonic testing system when ultrasonic waves propagate in the specimens. Results show that the relative nonlinear coefficients increase with the stress. The SORNT β' is approximately linear with the stress when stress is lower than 84.6% of the yield strength. The TORNC δ' is approximately linear with the stress when stress is lower than 76.9% of the yield strength.

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.

Thunderstorm days are used to show the lightning frequency happened somewhere. Through comparative analysis on the thunderstorm days data of 66 weather stations in Jiangsu province and lightning data of ADTD lightning monitoring, it presents that the correlation coefficient r became the largest at 11 km range, and the longest distance of thunderstorm artificial observation is 11-14 km. According to the study of lightning activities in Jiangsu province to get the statistical fitting function curve equation by thunderstorm days and ground flash density data. Test the actual application effect of fitting equation by calculating the average relative error of fitting equation and standard equation, then make sure the actual thunderstorm days in Jiangsu province and the cloud to ground flash density formula is Ng=0.0224 Td1.48.

Four photosynthetic bacterium Rhodopseudomonas spp., QDS2, QDS3, QDS4 and QDS9, were isolated and screened from the bottom sludge of Qingdao coast. In order to get a mass of PSB, we successfully optimized the culture conditions of four strains by orthogonal experiment and obtained the best culture conditions.

Installing, seismic affections cost and complexity of maintenance are different due to the different mechanical of dampers. With the data collected from experts, this paper calculates the weight of indexes by the method of Delphi firstly, and then evaluates dampers of cables by fuzzy comprehensive method. Conclusions are drawn as follows :(1) Reliability is the most important factor to evaluates dampers;(2) Oil damper and MR damper are weak in reliability, economics and complexity of maintenance compare with other dampers;(3) High damping rubber, viscous damper and friction damper lead the top three of all the dampers. Meaningful references are provided for engineers to select dampers for cables according the character of cable stayed bridges.