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The effect of Sulfobacillus thermosulfidooxidans, cultured respectively in the substratum containing ferrous ion or solid elemental sulfur in a long term, on the leaching behavior of pyrrhotite was revealed through leaching test and surface analysis of pyrrhotite leaching residues using XRD and SEM. It was demonstrated that there was significant difference in growth characteristic of S. thermosulfidooxidans, the leaching behavior and surface products of pyrrhotite when pyrrhotite bioleaching was conducted using S. thermosulfidooxidans cultured in different mediums, and it suggested that the difference was chiefly due to different energy metabolism pathways. The pyrrhotite leaching behavior using S. thermosulfidooxidans grown on ferrous ion in a long term was similar to that in the sterile acidic system, and only leaching yield was slightly improved. This was attributed to the ability to oxidize sulfur of S. thermosulfidooxidans was weakened and thus the effect of the generated sulfur could not be eliminated, which leads to low iron extraction and low S. thermosulfidooxidans reproduced ability for lack of growth energy. In the case of S. thermosulfidooxidans cultured in medium containing sulfur, The ability to oxidize sulfur was enhanced, the bacterium grew rapidly in the mid-term of leaching, which weakened the suppressing effect of sulfur film and improved significantly pyrrhotite leaching. However, a large number of jarosite was generated owing to the accumulation of ferric ions with the bioleaching processing, and the formed wrapping layer by jarosite and minor sulfur on mineral surface suppressed further leaching of pyrrhotite.

Metallization of Fiber-Reinforced Polymer (FRP) composites aggrandized their application to aircraft, automobile, and wind power industries. However, their application is impeded by insufficient coating adhesion strength. In order to enhance coating adhesion strength between metal coating and fiber-reinforced polymer composites substrate, a new electroless-electrolytic plating process is proposed. The plating process of composite includes the preparation composite specimens with interlayer, micro-roughening, decreasing, acid activation, electroless plating and electroplating. The coating adhesion strength was measured by pull-out test.

Zn-Sb based composite thin films have been prepared by radio frequency magnetron sputtering using a Zn4Sb3 compound target followed by thermal annealing. Sample structure and surface morphology were analyzed by X-ray diffraction (XRD) and atomic force microscopy (AFM). The electrical properties of the films were studied by Hall measurements. The X-ray diffraction patterns reveal that the intensity of diffraction peak of ZnSb phase is enhanced as temperature increasing. Results of AFM shows the rms roughness is getting big with increasing temperature due to the growing crystal grains. Hall measurements indicate that the Zn-Sb composite thin films annealed at different temperatures are p-type conducting with carrier concentrations being on the order of 1019 cm-3.

Microwave dielectric properties and microstructures have been investigated in the x Ca0.8Sr0.2TiO3 − (1−x) Li0.5Nd0.5TiO3 ceramic system. In the entire composition range, a single solid solution in the ceramic system was formed with the orthorhombic perovskite structure. As the Ca0.8Sr0.2TiO3 content of the ceramic system increased from 0.1 to 0.3, the dielectric constant (εr) increased from 114 to 144, the product (Qf) of quality factor (Q) and frequency (f) from 995 to 1,121 GHz, and the temperature coefficient of resonant frequency (τf) value from-83 to 94 ppm/°C, respectively. Simultaneously, the observed polarizabilities and the theoretical polarizability increased with rise in the Ca0.8Sr0.2TiO3 content. The τf value increased linearly with the increasing unit-cell volume. For practical application, a near-zero τf in the 0.2Ca0.8Sr0.2TiO3 −0.8Li0.5Nd0.5TiO3 ceramic with a Qf value of 1,025 GHz and a εr value of 132 were obtained at the sintering temperature of 1300°C for 4 h.

The oxygenated feed-water treatment technology of supercritical unit can effectively decrease the corrosion of water-steam system, and thus steam-water quality and operating efficiency are greatly promoted. In view of modes of feed-water treatment technology for supercritical unit, the characteristics of oxide film in thermal system under AVT and OT conditions are compared; and then, the principle of oxygenated feed-water treatment technology was elaborated. Besides, the oxygenated conditions, controlling of water quality, advantages, the relation between formation of oxide scale and oxygen plus are analyzed. Finally, the paper introduced weak oxiding feed-water treatment technology, with the principle of low oxygen and high pH value.

According to different melting point of paraffin type of PCM, has carried out some experimental research and analysis, through the visualization experiment method, the PCM phase change expansion coefficient is determined. At the same time, under the same conditions, for 30 #, 40 #, 50 # PCM storage heat release experiments, contrast analysis of the regenerative heat release, total heat release, and storage time on average water temperature difference factors. In addition, carried out more than melting point PCM cascade configuration related experimental heat storage properties, expect to achieve energy utilization efficiency.

Using the flux processing technique, the undercooling of pure silver melts could reach to 205K. Combining the Differential Scanning Calorimeter (DSC) technique, the specific heat of pure silver melts was measured, which showed a linear dependence on temperature in the range of the obtained undercooling from 0 K to 205K. The related thermodynamic properties of silver, such as the entropy change, the enthalpy change and the Gibbs free energy difference between the undercooled melt and the solid phase, were derived from the measured specific heat. The results showed that the model of Singh-Holz can reveal the reality of the non-equilibrium solidification more accurately than other models.

The oxygenated feed-water treatment technology of supercritical unit can effectively decrease the corrosion of water-steam system, and thus the steam-water quality and the operating efficiency are greatly promoted. In view of the mode of feed-water treatment for supercritical unit, the characteristics of oxide film in thermal system under AVT and OT conditions are compared; and then, the principle of oxygenated feed-water treatment technology was elaborated. Besides, the oxygenated conditions, controlling of water quality, advantages, the relation between the formation of oxide scale and oxygen plus are analyzed and discussed. Finally, the paper introduced weak oxiding feed-water treatment technology for supercritical unit, with the principle of low oxygen and high pH value.

This paper proposes a new solution to recognize and segment adhering bars. A support vector machine (SVM) is constructed according to the feature vectors of training samples to recognize the adhesions type of bars. The geometric feature values and moment feature values based on Blob regions in the image are extracted, which are the input feature vectors of support vector machine. The trained classifier is used for identifying the adhesions type of bars in the image. Finally, classification and recognition are realized by support vector machine. The experimental result shows that the recognition accuracy based RBF kernel achieves 100%. The method is feasible and effective for the recognition and segmentation of the adhering bars.

The dye-sensitized solar cell performances influenced by radiant intensity and illuminated area in concentrating photovoltaic system are investigated experimentally and discussed theoretically. The results show that, under the same irradiated cells area, the short-circuit current is linearly increasing with the radiant intensity and the open-circuit voltage follows a logarithmic function of the radiant intensity. And, it is turned out that the short-circuit current and open-circuit voltage are obviously enhanced by increasing the illuminated cells surface area at the same radiant intensity. However, that growth trends will decline with an increase of the illuminated area. The reason is more defects involved in the process of increasing illumination area. All results can be interpreted using an equivalent circuit of a single diode model. A good agreement can be observed from the fitting curves. It is of great significance for current photovoltaic research.

With the theory of ecology and ecosystem health evaluation, the factors impacting river ecosystem health are analyzed and an evaluation system is built. The connotation of river ecosystem responding to the cascade development of reservoirs is studied. The response of typical plankton, benthos, fish to cascade development is identified. According the living and breeding habits of key species, typical representatives are selected to establish the grading standards of ecological health and evaluate ecosystem health as well as the effect of eco-hydrology regulation under cascade development of typical reservoirs. Results show that the annual distribution of runoff tends to be balanced, with reduced amount of suspended sediment in downstream; species fond of shallow water and rapids suffered decreased habitat space and a decline in its number, resulting in decreased diversity of fish species; and the quality of some river segments failed to meet the standard.

job shop scheduling is one of the most difficult NP-hard combinatorial optimize problems, in order to solve this problem, an improved Genetic Algorithm with three- dimensional coded model was put forward in this paper. In this model, the gene was coded with 3-D space, and self-adapting plot was drawn into conventional GA, then the probability of crossover and mutation can automatic adjust by fit degree. The instance shows that this algorithmic is effective to solve job shop scheduling problem.

Using nonlinear finite element method, the three dimensional nonlinear analysis of the radial steel gate of a reservoir is carried out. In the analysis, the radial steel gate considering and without considering the stiffeners of the panel is analyzed to investigate the effect of the stiffener to the panel. In the corrosion sensitive analysis, the panel of the gate is divided into three sections, and the nonlinear analysis is carried out for each section that is rusted with different corrosion depth. The corrosion sensitive section and the stress variation with the corrosion depth are present.

Three aryl and three naphthylmethylene derivatives containing thiadiazole ring have been synthesized. The structures of target compounds were characterized on the basis of spectral (FT-IR, 1H NMR, and MS). The optical properties were detected using UV-vis absorption spectroscopy and fluorescence spectroscopy. The absorption spectra of 1a, 2a and 3a substituted by naphthylmethylene are primarily characterized by a peak around 284 nm originating from naphthalene, which is different from that of compounds 1b, 2b and 3b. Compared to 1a and 2a (separated by a saturable atomic cluster −CH2−), the maximum absorption wavelength of 1b and 2b takes on obvious red-shifted, which is from thiadiazole and benzene with more large conjugated system. The fluorescence intensity of 2-(4-aminobenzoyl) amide-5-naphthylmethylene-1,3,4-thiadiazole (3a) was significantly higher than that of 5-(4-aminobenzoyl)-1,3,4-thiadiazole (3b) due to the presence of naphthalene.

3D model segmentation is a new research focus in the field of computer graphics. The segmentation algorithm of this paper is consistent segmentation which is about a group of 3D model with shape similarity. A volume-based shape-function called the shape diameter function (SDF) is used to on behalf of the characteristics of the model. Gaussian mixture model (GMM) is fitting k Gaussians to the SDF values, and EM algorithm is used to segment 3D models consistently. The experimental results show that this algorithm can effectively segment the 3D models consistently.

Fixed-abrasive wires, such as electroplated diamond wires and resinoid diamond wires, employed for slicing ingots have the problems of high tool wear. A novel brazed diamond wire has been developed to overcome these problems. This paper investigates the effect of process parameters, including brazing temperature, brazing time and brazing filler composition, on the brazed diamond wire manufacturing with CuSnTi brazing filler. The 3D micro-video system was used to observe the brazed diamond wire surface. Tensile, bending and torsional test were carried out to evaluate the mechanical properties of brazed diamond wire. A brazed diamond wire with 3km length was fabricated with the optimization process parameters, which was successfully used to slice glass.

A malononitrile derivative, 6-Amino-5,5,7-tricyano-3,3a,4,5-tetrahydro-2H-indene-4- Spirocyclopentane was synthesized in ethanol with malononitrile and cyclopentanone as raw materials. It was characterized by X-ray single crystal diffraction analysis.The crystal of the title complex belongs to Triclinic, P21/c space group with a=6.4687(13)Å, b=8.9901(18)Å, c=12.004(2)Å, α=93.55(3) deg, β=91.86(3) deg, γ=92.25(3) deg. V=695.8(2)Å3, Z=2, F(000)=278 and final R1=0.0524,WR2=0.1497. X-ray analysis reveals that The cyclohexene ring has a distorted half-chair conformation and the cyclopentene and cyclopentane rings adopt envelope conformations. The dihedral angles between planar fragments of the cyclohexene and cyclopentene rings and of the cyclohexene and cyclopentane rings are 10.67 (7) and 87.33 (3)°, respectively. In the crystal, intermolecular N-HN hydrogen bonds link the molecules into infinite chains running in the [10] direction.

In this paper, we mainly introduced demonstration project of flue gas desulfurization and denitrification achieved by ozone oxidation and alkali wastewater. The System showed high automatization, which performed good adaptability and load tracking capacity on the concentration of SO2, NOX and variation of flue gas. Meanwhile, outlet concentration of the SO2 and NOX could meet the design requirements. The experimental results showed that the overall economy of designed process had certain advantages compared with conventional desulfurization and denitrification technologies.

It is important to develop low cost and efficient technique for simultaneous removal of SO2 and NOX from flue gas. In this paper, ozone oxidation and alkaline wastewater washing process was employed for flue gas desulfurization and denitrification in a 75t/h coal-fired boiler. In order to optimize the operation parameters for SO2 and NOX removal, the influence of several parameters, such as molar ratio of [O3]/[NO] and flue gas temperature on the oxidation rate of NO, oxidation rate of NO, alkaline water level in aeration tank, alkaline water rate and mole ratio of [NaOH/ (SO2+NOx)] on the removal efficiency of SO2 and NOX have been studied. The experimental results showed that molar ratio of [O3]/[NO] had limited effect on the oxidation of SO2, while NO oxidation efficiency improved with the increase of [O3/NO] molar ratio and it reached to ~ 90% at molar ratio of [O3]/[NO] = 1.4. Flue gas temperature performed slight influence on the oxidation of NO in the range of 60 to 120 °C, and had adverse impact on the removal of SO2 and NOX. NOX removal rate was enhanced with increasing NO oxidation rate and achieved to a high level at NO oxidization rate of ~50%. Mole ratio of [NaOH/ (SO2+NOx)] had significant impact on the removal rate of NOX, while it showed limited effects on that of SO2. The increase of alkaline aeration water level and alkaline water rate would definitely lead to a higher removal rate for both SO2 and NOX. An optimized removal rate of 93.6% for SO2, 77.6% for NOX and 99.1% for dust were obtained under the water level of 20cm and volume of 74.5t/h.

Compression deformation will cause a micro-spring to buckle, and structural parameters, constraint conditions and structural forms of a micro-spring will affect its critical load and buckling mode. In order to study the influence on the micro-spring’s stability caused by structural forms and find a structure to improve its critical load in the end, this paper designs a new kind of parallel micro-springs, which consists of two same-structured S-shaped planar micro-springs. We have carried on eigenvalue buckling analysis on the parallel micro-spring by software ANSYS, and have gotten its six orders’ buckling mode. Because the critical load of the parallel micro-spring may change with the length of the beam connecting the two sub-springs, this paper studies the effect of the beam’s length on the parallel micro-spring’s critical loads and buckling mode. From comparing the analysis results between parallel micro-spring and single micro-spring with same stiffness, this paper concludes the stability’s degree of improvement.

Ce3+/Tb3+/Sm3+ co-doped phosphate glasses were prepared by melt quenching method. The full colors including blue, green and reddish orange emitting were observed simultaneously in the photoluminescent spectra of the glasses at 377 nm excitation, and the combination of these three emitting allows the realization of white light emitting. The CIE chromaticity coordinate (x=0.339, y=0.331) of the emission from the glass is close to the standard white-light illumination (0.333, 0.333). Moreover, the tunable luminescent color and chromaticity parameters could be realized by varying the content of Tb4O7 dopant in the glass composition, which is promising fluorescent materials for white light emitting diodes applications.

According to the method described in Technical Manual of Aircraft Noise Evaluation Procedures, this system can predict the EPNL (Effective Perceived Noise Level) of aircraft take-off, approaching and side boundary. The system also contains the function of managing andcalling NPD database, and can assess the predictive value basing on the noise stringency curve. This saves a number of cost for the airworthiness certification of aircraft noise, and is a new engineering practice which has a good application value.

For the thermal environment and the warming requirement of Vehicle, carry out experiment study on heat storage characteristic of phase change materials (PCM) encapsulated by Spherical stack. heat storage and release experiment process , changing factors such as medium flow rate and melting point which impact on PCM heat transfer characteristics , melting rate and response time have been analyzed. The results show that within the scope of experiment high medium flow rate is conducive to promote PCM melting rate and heat storage. In the experiments process, high melting point of PCM storage heat grade is high, but the low melting point of PCM is more suitable for vehicle motor, batteries in low temperature waste heat recovery. At the same time, multi-melting point PCM storage device with spheres piled encapsulated delamination mixed stowage was better satisfy the different condition of waste heat recovery and utilization than single melting point of PCM.

A diagnosis of corrosion failure in steel wire ropes based on wavelet and support vector machine (SVM) is investigated. Wavelet decomposition and reconstruction algorithm is used to denoise the magnetic flux leakage (MFL) signals, then peak value, trough value, peak-to-peak value and energy parameters are extracted as fault feature vectors, and a SVM classifier is designed and used to conduct the fault pattern recognition. The experimental results show that the accuracy of the SVM classification achieves to 100%.

With the development of nondestructive testing (NDT) technology for wire ropes, various detection methods are constantly refined and improved. The primary and representative NDT methods are suitable for the detection of wire ropes including manual inspection, acoustic emission method,acoustic-ultrasonic method,eddy current method,electromagnetic method and metal magnetic memory method. Meanwhile, the research results of our laboratory based on the theory of the magnetic flux leakage to detect wire rope’s fault detection will be displayed. Through comparisons of methods’ merits and weaknesses,it also has brought forward the new trends about adopting metal magnetic memory to predict the lifetime of the steel wire ropes,which has greater value in theory and application for improving the precise detection of the in-service ropes.

With the progress of science and technology, people's desire to improve the work efficiency became stronger and stronger. The demand for applied robots is sharply growing. Compared with the traditional rigid robot, the flexible mechanical structure has the advantages of compact and maneuverable. Thusly, this paper follows the direction of low-cost flexible structure, came up with a four-wire flexible manipulator and completed the prototyping research. This manipulator consists of flexible picking paw, flexible picking arm and control system three mainly parts, can be used in various fields.

Hydrophobic surfaces with contact angles greater than 90° and roll-off angles below 10° for water have been developed, based on low energy surfaces and rough texture on the micro-and nanometer scales. In this study, we fabricated a hydrophobic surface on a aluminum alloy substrate using the method of chemical etching without being modified by organic liquids such as surfactant-based solutions, alcohols, or alkanes. The measurement showed that the as-prepared surfaces possessed roughness on the micrometer scales by laser scanning confocal microscopy. The etched aluminum alloy surfaces had a maximum water contact angle of 120o by using a water contact angle measurement. The forming course of the aluminum alloy etched surfaces with pores was analyzed. The wettability of the etched aluminum alloy surfaces is reinforced by means of controlling the surface rough texture on the micrometer scales.

Rapid prototyping and the silicone mold are more and more widely used in the process of new product development, it has become the hotshot in this field. With the method of single factor experiment and using rapid prototyping based on FDM technology as a master pattern,several main factors influence the dimensional precision molding products is analyzed and the redeem measures are put forward during silica gel mold casting process. The study has importance in guiding the practical application of the silicone mold casting products and provides the experimental basis on research and development to silicon mold technology.

Diamond-Like Carbon (DLC) films were deposited on quartz substrates by using a gas mixture of hydrogen-methane-oxygen in the Star-Shape Microwave Plasma enhanced Chemical Vapor Deposition (MPCVD) reactor. The pretreatment parameters include the pretreatment methods and the pretreatment time was optimized. Results showed that ultrasonically abrasive in the acetone solution with nanocrystalline diamond powder in it was an efficient pretreatment method to advance the deposition of DLC films, and 10 minute turned to be the most appropriate time for this pretreatment. The Fourier Transform Infrared spectrometer (FTIR) showed that the DLC films synthesized by the optimized technics have high transparence fit for optical applications. These indicated that the Star-Shape MPCVD reactor was the perfect equipment for the volume-produce of DLC films for its unique big reactive cavity.

Due to the 3c products develop faster in the direction of thin, light, short and small, thin-walled plastic parts of the vacuum casting attaches great importance to people. The quality of the thin-walled plastic parts can be guaranteed with the method of vacuum casting numberical simulation . Using Moldflow, we analyze the best location of the gate、the fluidity of the material casted in the mold and produce a vacuum casting part .The vacuum casting basic process was described in this paper. The CAE (Computer Aided Engineering) analysis applied to vacuum casting effectively guide rapid mold made.

Multiple fractures are needed by hydraulic fracturing in order to improve the horizontal well productivity of a single well in tight gas reservoir. The calculation accuracy of productivity influences on the fracturing optimization results and the success ratio and effectiveness of fracturing treatment. This work focuses on analyzing the influence of fracture parameters on fractured horizontal well productivity in tight gas reservoir through establishing a productivity prediction model of fractured horizontal well, considering the interference between fracture and fracture and the wellbore pressure drop. Results show that the fracture parameters, such as fracture number, fracture interval, fracture conductivity and fracture length, have different influences on the productivity of fractured horizontal well and thus, the effects of fracture parameters should be taken into account when designing the fracturing treatment.

The purpose of frac fluid flowback is to outflow the fracturing fluid and prevent the proppant backflow, which determines the effect of fracturing fluid flowback. The fracturing treatment in field lacks relevant theoretical models for prediction. Therefore, this work focuses on establishing the flowback model of hydraulic fracturing for multilayer fractured wells. Then the wellhead pressure and fluid flowback volume are predicted based on the actual parameters of fracturing treatment in the process of flowback and are compared with the field data of frac fluid flowback. Results show that the wellhead pressure and fluid flowback volume calculated by the model are consistent with the field data. The sand production ratio of the three wells during the flowback process is lower than 1% indicating that the optimized parameters achieve the purpose of flowback operations and reduce the flowback volume of the proppant.

Three oxidant decontaminants, including NaClO, H2O2 and an organic peroxyl acid, were introduced to destroy the cyanide ion. The residual cyanide ion concentrations in different decontamination water were detected by a cyanide ion selective meter. Before the detection process, the oxidants left in the cyanide decontamination water were pretreated by adding a certain amount of Na2SO3. Results showed that starch-iodide solution indicator method presented a perfect function on determining the dosage of Na2SO3. Values of the relative mean deviations on residual cyanide detection were below 5%. After the decontamination water was deoxidized by Na2SO3, whether the sample distillated or not could not affect the value of CN- quite much. Non-distillation was confirmed alternative in the detection of cyanide ion decontamination water. Too much standing time would lead to a relatively lower CN- concentration, especially in that of non-distillation.

The data processing of static engine noise test, especially the elimination of ground reflection to access the free-field sound pressure level, has been defined as one of the basic steps in aircraft noise prediction on the noise certification procedure by ICAO[1,. Based on the importance of the method, this paper will study the impact of the ground reflection effects on the aircraft engine noise experimental, especially made a detailed overview for the calculation method of reflective index.This paper also gives the method of fixing this effect to get the free field sound pressure level, while making experiments to verify the feasibility of this method, so that make the noise analysis and prediction according to the noise certification procedures.

Excavation blasting has a great impact on the buildings, therefore, it is important to control blasting vibrations. In this paper, based on the time-energy density analysis and wavelet packet analysis for measured data of blasting vibrations, some useful results can be concluded. Firstly, the energy of Millisecond Detonator Blasting (MDB) vibration signals in the 0~200Hz band accounts for 90.06% of the total energy, and its advantage energy mainly distribute in low-frequency band. However, the energy of Digital Electronic Detonator Blasting (DEDB) vibration signals in the 0~600Hz band is 96.08% of the total energy, its advantage energy mainly distribute in wider band. Moreover, the time-energy density curve of DEDB doesnt have the abrupt and separated fluctuation, which indicates the interference and superposition of DEDB are very distinct. The controlled DEDBs and tunnel support measures of this project have achieved a good effect. The comprehensive benefits are remarkable and it has an important significance for improving the level of blasting technology.

To the pusher and variable load synchronous motion of hydraulic dual-cylinder system, the "Bang-Bang" control mechanism and the non-continuous control technology are adopted. The hydraulic system that used the ordinary realizes a synchronization error less than two percent. The stability and reliability of the system are improved and the cost of the system is reduced. Especially in the pusher and other industrial areas, the hydraulic system is more suitable for engineering application. By the ability of computers software servo control, the output of the application system can meet the performance standard and make complex mechanical control. it proves that a non-continuous control method is an effective way to carry out the digital control.

According to the function requirement of humanoid robot, advance a distributed control system of humanoid robot control system which use AVR (Mega2560) microcontroller as its main computer. The ATmega168 SCM acts as the core chip of the Joint controller, it receives instructions by serial port communicating with the main computer, and output byte signal,which processed by 74HC595 will finally turn into PWM signal and realize the servo control. Experiments show that the proposed control system is stable and feasible.

The paper developed a pendulum impact testing machine. The impact testing machine is mainly used for dynamic mechanical properties testing and anti-destructive testing for the steering assembly. The mechanical system of testing machine adopts the impact type of pendulum acceleration of gravity. It adopts optical-electricity encoder to control the pendulum angle of oscillation. The movement of the pendulum is controlled by gear reducer motor and clutch. The curve of the impact force changing along with the time is half-sine wave during the whole process.

A failure criteria basing on Drucker-Prager yield criterion for geomaterials is modified in terms of the inherent anisotropy of the friction angle and the dilation angle. To implement the model in a numerical way, the corresponding consistent return mapping algorithm is formulated and by dividing the scalar product of the stress rate and the strain rate into the deviatoric and spherical parts, the consistent elastoplastic tangent modulus matrix is obtained. Then, the codes are introduced into finite element software ABAQUS via the UMAT. An example has been presented illustrating influence of the anisotropic degree on the bearing capacity and the pattern of strain localization.

There are many difficulties to design, processing and research on numerical simulation for Francis turbine because of the complexity of blade shape and the difficulty of solid modeling. Based on two-dimensional wooden patterns of Francis turbine blades, this article aims to complete blades three-dimensional modeling for Francis turbine runner with long and short blades by means of Pro-E software which has powerful 3D modeling function. After comparing three kinds of available methods to generate blade across section which provided by Pro-E, finally completed blades three-dimensional modeling by method of generating across section with point files, established a smooth and accurate three-dimensional model. The method provides an accurate physical model for the numerical simulation of the Francis turbine with long and short blades, as well as provides a feasible approach for hydro-mechanical blades modeling.

This article is based on the research of natural ventilation and indoor thermal environment. By selecting Xuzhou Long-distance Passenger South Station as a typical large space building and simulating the ventilation of the building, the article proposes the optimization strategies of Form, Space and Material and validates these strategies, to provide the energy-saving strategies for the design of Long-distance Passenger Station and large space architecture.

Hydraulic fracturing is an effective measure to increase oil production for the development of low permeability reservoir. The selection of perforating parameters has a direct effect on the fracture expansion, formation fracture cracking pressure and even the implementation success of fracturing in that the fracturing processing fluid and artificial fracture all need to pass through the extension of perforation. In field application, the selection of perforating parameters is usually determined base on experience without combining with the actual data of the hydraulic fracturing wells. This work focuses on analyzing the influence of perforating parameters on the productivity of fractured well based on an established productivity prediction model through analytical method.Results show that, take a specific area of Changqing oil field for example, the perforation diameter has little effect on the productivity after fracturing, the other optimized perforating parameters are as follows: the perforation degree 30~40%, perforation density 8~12 perforation per meter, perforation depth 0.2~0.3m. The results are helpful to guide the optimization of perforating parameters in low permeability reservoir.

In general, the scale of production, exploitation period and the economic benefits of oil and gas field are, to a large extent, depended on the selection, deployment and adjustment of well patterns, especially for tight reservoir. So far, some problems exist in Changqing low permeability oil field, such as the effective displacement system is not easy to be established, a low utilization efficiency of injection water, low oil production and so on. Therefore, five kinds of different well pattern schemes are designed. Then, the well pattern schemes are optimized through numerical simulation method based on the exploitation index including the daily oil output per well, moisture content and oil recovery. Results show that the well patterns of horizontal-vertical wells have better development efficiency than the well patterns of vertical wells. For the optimized well pattern, when the horizontal segment length of horizontal well is 300m, the optimalizing well spacing is 400m and the optimalizing row spacing is 100~150m.

The modification of natural dyes tea polyphenols is discussed in the silk dyeing. Tea polyphenols and 3-chlorine-2 - hydroxypropyl trimethyl ammonium chloride (CHPTMA) are ionized in alkaline condition, and modified tea polyphenols are prepared. The effect of CHPTMA modifier dosage, pH, temperature and time condition to modification of tea polyphenols are studied systematically. The optimal process of modification is obtained. The dyeing & finishing functional performances on silk were performed experimentally and verified theoretically.

At present, the research is not enough for the correlation of structure and stress-strain characters in domestic.The paper aims how the change of water content and confining pressure influence the stress-strain characters of intact loess and remolded loess by consolidated drained triaxial shear test for the Shanxi loess.The results showed that: the intact loess have structure, and the strength of intact loess is larger than remolded loess in the same condition. With the increasing of water content or confining pressure, the stress-strain of intact loess and remolded loess will tend to coincide and the impact of structure feature for loess strength will weaken.

In this paper, the bioleaching behavior of three pyrites from different geological origins (high-temperature hydrothermal, low-temperature hydrothermal and coal sedimentary) by L. ferriphilum was studied. The internal structure of three pyrite samples were investigated using optical microscope. The results show that the physical characteristics and internal structures of pyrites from different geological origins are different, and this causes the divergences of their bioleaching behavior. High-temperature hydrothermal pyrite (n-type semiconductor tested) is not almost dissolved and the leaching rate is only 0.58%, while the leaching rate of low-temperature hydrothermal pyrite and coal sedimentary pyrite (both of p-type semiconductor tested) are 15.25% and 27.50% respectively. The Leica optical microscope test of p-type semiconductor pyrites indicates that coarse particle of low-temperature hydrothermal pyrite is crystallized well and sedimentary pyrite consists of fine-grained crystal with poor crystallinity. This was suggested to cause the divergences of the bioleaching rate of both p-type semiconductor pyrites. In view of mineralogy, the semiconductive type of pyrite is the primary factor affecting its bioleaching. Furthermore, the different internal structure of pyrites will further have an influence on bioleaching for the same semiconductive type.Key words: pyrite; bioleaching; L. ferriphilum; geo-genetic

Pyrrhotite ores are always mingled with very finely disseminated gold and other precious metal particles, which raise the disposal of such refractory ores to bacterial leaching level. In this paper, the bioleaching tests of pyrrhotite were carried out in Erlenmeyer flasks with moderately thermophilic Leptospirillum ferriphilum (at 40℃) and extremely thermophilic Acidianus manzaensis (at 65℃). The effects of bacterial strains, temperature, and acid tolerance on the extraction of iron were investigated, and the bioleaching residues were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that high temperature and low pH have important positive effects on the dissolution of iron under abiotic control, and extreme thermophilies are unsuitable for leaching pyrrhotite. As the pH value rapidly increased to above 4.4 and amounts of sulfur and goethite were generated at the initial stage during the process of bioleaching by A. manzaensis, the cell concentration dramatically declined. In comparison, more than 44% extraction of iron was achieved in the presence of L. ferriphilum after four days of leaching. At the end of bioleaching, jarosite, sulfur and goethite, which could effectively block bioleaching process, were detected on the surface of residues by using XRD and SEM.

This paper uses time-history analysis method to consider the effect of 3 kinds of seismic waves by means of finite element software Ansys, analyse earthquake response of 5 kinds of models, compares effect of structural performance of frame structures with different types of stairs. The results show that different types of stairs diversely affects period, stiffness, mode of vibration, mechanical performance, etc, after consideration of stairs in calculating. Although types of stairs different, it shows mainly that stairs make much larger contribution for stiffness parallelled to stairs, less contribution for stiffness perpendicular to stairs, each layer just affects stiffness this layer. It is not simple to consider different types of stairs as general supports.

Arsenic concentration changes in small-scale simulating constructed wetland composed with shale ceramic, zeolite, quartz sand and Pteris vittata were examined. During arsenic removal by the constructed wetlands, arsenic interception by the natural media played the main role in the early stage and Pteris vittata uptake played the key role for arsenic removal in the later stable stage. When As (III) concentration in inflow was about 1 mg/L, the arsenic removal ratio by the two was between 22.2% and 66.6% and kept about 33% in the end. Arsenic average content in fronds and roots of Pteris vittata after experiments were respectively 17610 and 2491 mg/kg. Transfer factor was 7.08. Compared with batch tests, arsenic content accumulated in plants increased significantly.

The stress-dependent permeability of ultra-low permeability rocks has a significant impact on the seepage. A number of experimental studies on the variation of permeability with stress change in low permeability reservoir have been done, but few are involved in ultra-low permeability cores. In this study, first, we fabricated the shear-stress microfracture cores and then the stress sensitive experiments were conducted. Second, a fracture deformation model was introduced in order to depict the stress sensitivity features of fracture media theoretically. Finally, a comparison of the theoretical curves with the experimental data had been done. The results show that the fabricated microfracture cores can be used in the permeability stress sensitive experiments. The permeability stress sensitive hysteresis of the microfracture cores is not obvious and the recovery degree of stress sensitive hysteresis is high in the unloading cycle for the grains were compacted in the process of shearing. The theoretical curves have the desired behavior which is consistent with the experimental data well. It indicates that the method of fabricating microfractures can similarly reveal the stress sensitivity features of the real microfracture ultralow permeability reservoir. This study do great benefit to reveal the stress sensitivity features of ultra-low permeability reservoir.