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Phase transformation of austenite continuous cooling process in low carbon high strength sheet steel has been researched by DIL805 thermal mechanical simulate. The Austenite continuous cooling transformation (CCT) diagram of steel has been determined by dilatometry and metallography. With the increase of cooling rate, ferritic transformation, perlitic transformation, bainite transformation and martensitic transformation have produced in the organization. Mathematical equations of phase transformation point-cooling rate and phase variable-cooling rate have been established and phase transformation model of high fit degree has been gained by regression calculation. The results show that calculated value and experimental value are nearly similar, so the phase transformation model is feasible.

Factor group analysis on the deformed pyrochlore-structure hydroxyl transition metal halidesM2(OH)3X(M= Co, Fe and Mn;X= Cl, Br and I) with the crystal symmetry ≡D3d5of space group No. 166 for their infrared (IR) and Raman spectroscopic studies are, for the fist time to the best of our knowledge, reported. Through a standard factor group analysis, we predict that there are 17 IR active normal modes (7A2u+ 10Eu) and 12 Raman active modes (5A1g+ 7Eg), caused by five atomic site groups [HOM3], [OM3], [MO4X2], [ClM3] and [MO6], where the black body letters represent the site atoms. In addition we figure out all the atomic displacement patterns of 12 Raman active normal modes, and point out these results are completely same as those of the famous geometric frustration material Herbertsmithite ZnCu3(OH)6Cl2.

The low temperature Raman spectroscopic (4000-95 cm–1) investigation on the hydroxyl cobalt chloride Co2(OH)3Cl and deuteroxyl cobalt chloride Co2(OD)3Cl polycrystalline samples has been performed from the room temperature down to 4 K closing to the liquid Helium temperature. Lineshapes of Raman modeEg(about 130 cm–1assigned to the normal symmetrically bending vibration mode of the [ClCo3] group for both kinds of samples) are found to be apparently asymmetric Fano lineshapes when the temperatures are below 230 K. This phenomenon is preliminarily attributed to the effect of electron-phonon coupling and a continuum of electronic states centered at about 16 meV with an upper limit 18.5 meV is suggested in this report.

The crystal structures, band structures, density of states, charge density, overlap population and optical properties of pure anatase TiO2 and Pr-doped anatase TiO2 were studied by using the plane-wave pseudopotential method based on the first-principles. After Pr doping, the valence band and the conduction band moved down and became dense, energy gap became narrow and a impurity band which consists of Pr 4f states appeared. And the dipole moment got improved, which is good for the separate of the electron-hole pairs. These effectively overcome two huge shortcomings of TiO2. Besides, Pr-doped anatase TiO2 produced more carriers which have good transport properties and the absorption spectra of Pr-O bond appear in the region that the wavelength is longer. The calculation results of optical properties show that the absorption edge occured red shift, which means the photocatalytic activity of anatase TiO2 got remarkable improved during visible-light region. This conforms to the previous analysis. So the photocatalytic activity of anatase TiO2 got remarkable improved after Pr doping.

The activity response of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), ATP enzyme activities ofEscherichia coliQ8,Bacillus subtilisL11, andBacillus cereusOL-1 following exposure to 1,2-dichlorobenzene (1,2-DCB) was investigated. The bacterial strains were treated with the different concentrations of 1,2-DCB. Results obtained indicated that SOD and CAT activities in the tested bacteria increased significantly in a concentration-dependent manner after different concentrations of 1,2-DCB were applied. The activity of SOD inB. subtiliswas stimulated and reached the highest level after treatment with 10 mg/L 1,2-DCB for 3 h. ForB.cereusOL-1, there was another stimulation of SOD activity after 1,2-DCB application for about 5 h The stimulation by 1,2-DCB showed a relative lag forE. coli. 1,2-DCB had an evident influence on ATPase activity in the three bacteria within a relatively short period. 1,2-DCB would have caused a certain oxidative stress on the three bacteria which may not only elevate SOD and CAT activities but also generate new SOD isozymes to antagonize oxidative stress. All indirectly reflect the existence of poisonous and harmful material in the environment , and can indicate the influence of pollution sensitivily. Therefore SOD, CAT and ATP enzyme activity in microbial body can be regarded as a molecular index of polluting ,which is feasible.

The Realizable k-ε turbulent model is employed to simulate the flow pattern in forebay of pumping station, and the precision of simulated results is verified by experimental data. And then the flow pattern of the different unit commitments is simulated to acquire the flow characteristics in forebay, such as circulating flow and velocity distribution, and the velocity uniformity of forebay is analyzed to search the optimal units commitment. The research results show that: under the different unit commitment, the characteristics of flow in forebay is so different that the effect of the diversion piers is not always advantageous; comparing the velocity uniformity, the optimal operation strategy is to try to operate the middle pumps, and the operation strategy of operating pumps on both sides is better than that of opening pumps on one side.

The potential effect of 1,2-dichlorobenzene (1,2-DCB) on anaerobic microbial populations was investigated in a flooded wetland soil. Numbers of anaerobic fermentative bacteria (AFB), denitrifying bacteria (DNB) and hydrogen-producing acetogenic bacteria (HPAB) were numerated by three-tube anaerobic most-probable-number (MPN) methods with anaerobic liquid enrichment media. In anaerobic microbe groups, the changes of bacterium group were not the same. 1,2-Dichlorobenzene had the maximum influence on microbial groups of wetland soil at the initial pollution. In dealing with 14-35 days, bacterium groups in each processing soil have different amplitude bouncing back. In the experimental process, bacteria which produces hydrogen and acetic acid is most sensitive to 1,2-Dichlorobenzene. Hydrolysis fermentation bacteria second, and denitrifying bacteria was the smallest.

Cu (In, Ga)Se2 (CIGS) thin film was prepared by ion beam sputtering Cu, In, Se and evaporating Ga elements continuously on BK7 glass substrate and the 4-layer film was then annealed at 400 oC for 1h in the same vacuum chamber. The CIGS thin film is single-phase with chalcopyrite structure and has a preferential (112) orientation. Its elemental composition approaches the stochiometric composition ratio of 1:0.7:0.3:2 and it consists of densely packed grain clusters. An energy band gap of about 1.30 eV and an absorption coefficient of 105 cm-1 are obtained. Thus, an optimization of the fabrication for CIGS thin films was achieved.

This study reports the successful preparation of Cu (In, Ga)Se2 (CIGS) thin film solar cells by ion beam sputtering with a chalcopyrite CIGS quaternary target. The films were fabricated with different beam currents. The thin films were characterized with X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) and hall effect-measurement system to study the microstructures, composition, surface morphology and electrical properties, respectively. Experimental results show that both the films are chalcopyrite structure, the Ga/(In+Ga) ratio, Cu/(In+Ga) ratio and Se/(Cu+In+Ga) ratio are decrease with the beam currents increase, the surfaces morphology of the films are dense, and the resistivity of the film deposited with the beam current of 40mA is 0.56Ωcm, with a carrier concentration of 4.11Χ1018cm-3 and mobility of 2.73cm2V-1s-1. The resulting film exhibited p-type conductivity.

The number of projection affects the reconstruction quality in computed tomography system. Larger projection number will lead to better reconstruction quality. On the other hand, less projection number can reduce the radiation dose, save time and keep the patients comfortable. The optimal number of projection compromises both the mathematical accuracy and practical requirement. The purpose of this paper is to find the relationship between the projection number and the noise properties of reconstructed cross-section. It can provide references for researchers on CT application. A micro-CT system is utilized to validate the relationship between projection number and reconstruction quality in fan beam geometry. Full-scan and short-scan method are applied to reconstruct the specimen. Compared with full-scan method, short-scan can reduce radiation dose with the same step angle, and it can achieve better results with the same projection number when the sample data is sufficient.

In accordance with the technical features of large capacity, non-linear and dead time temperature resistance kiln system.a fuzzy predicted coordinated control algorithm is stated .Enhance tracking and anti-inference capabilities of The algorithm. Simulation results indicate that this method is better adaptive to the alteration and improverer the static precise that PID control.

Trichloroethylene is one of chlorinated organic compounds widely used as a solvent and degreasing agent in industry. Because of uninformed disposal in the past, trichloroethylene has become one of major contaminant in environment, and this situation has brought about a serious public concern for its toxicity. A promising approach to solving this problem is bioremediation using degrading-bacteria. A bacterium(strain TC-1) was isolated from environment, which could degrade trichloroethylene. It was preliminary identified as the genus of Sporosarcina sp.. The results showed that the optimal degradation temperature, degradation time, rotary speed and the initial pH of fermentation medium were 25°C, 60 h, 180 rpm and 7.5 respectively, the ratio of degradation reached 95.56% under this conditions.

Dyes are usually difficult to be decolorized due to their complex chemical structures. In this work, a bacterium which had the ability of decoloration on synthetic dyes was isolated from Yancheng printworks and was identified as Pseudomonas aeruginosa. The effects of concentration of the dye concentration, cultural time, cultural temperature and initial pH of cultural medium on the efficiency of decoloration were investigated. The result showed that the optimal cultural conditions was: dye concentration was 50mg.L-1, cultural time was 72 h, cultural temperature was 28°C, initial pH of cultural medium was 7.0.

The potential effect of 1,4-dichlorobenzene(1,4-DCB) on Microbial Populations and enzyme activities was investigated in a flooded wetland soil. The results showed that the number of actinomycetes declined significantly after the treatment of 1,4-DCB at different concentrations, and the amout of bacteria and fungi were significantly decreased in soil samples treated with higher than 200 mg/Kg. 1,4-DCB at over the range of selected concentrations could completely inhibit urease activityin the first 28 days.1,4-DCB at the concentration lower than 100 mg/Kg dried soil stimulated the activity of catalase , while the others showed an inhibition during period of incubation. Results indicated that these two enzymes are sensitive to 1,4-DCB contamination.

Outdoor electrical insulators form an important link in an electric power system. Along with the traditional insulators like glass and porcelain, presently the polymeric insulators are also used world widely. These polymeric insulating materials are very sensitive to various environmental parameters such temperature, raining, pollution, UV-radiations and icing etc. which seriously effect their electrical, chemical and hydrophobic properties. This paper shows a dynamic change of hydrophobicity on the surface of polymeric insulator under different environmental and contamination stresses. The hydrophobicity decrease of polymeric insulating surface due to rain and icing, hydrophobicity transfer status though different pollution layers and hydrophobicity recovery at different temperatures, humidity and wind speed are carried out in this paper. The hydrophobic characteristics are studied by measuring static contact angle on the surface on polymeric insulating material.

CdS thin film was deposited onto glass substrates by the chemical bath deposition. The deposition temperature was maintained at 75 °C. The crystal structure, surface morphology, optical and electrical properties have investigated employing X-ray diffraction (XRD), scanning electron microscopy (SEM), spectrophotometer and seeback coefficient measurement, respectively. The XRD reveals CdS thin film grown at 75 °C has the mixed hexagonal and cubic structure. The optical band gap energy is 2.4 eV. The seeback coefficient is 197.3μV/k at room temperature. The electric resistivity of CdS thin film is in the order of 10000Ω•cm.

Surface subsidence has some peculiarities for the mining of the Han jia wan coal mine. Based on the surface movement observation of 2304 working face in Han jia wan coal mine, mining strata movement parameters are analyzed, the main factors which influence the formation of surface cracks in the gob are proposed and the failure mechanism of surface movement and deformation are studied for the mining of shallow coal seam and thick loose bed. Correlative parameters are presented and scientific basis is established for the coal mining under buildings, rail and water and the leaving of the safety pillar in the future.

Raman spectra of the geometrically frustrated material sample β-Co2(OH)3Cl have first, to the best of our knowledge, been measured down to liquid nitrogen temperature using the experimental conditions of 10X-objective @ 60 mW and 50X-objective @ 5 mW, respectively. It is found that most Raman bands blueshift with decreasing the sample temperature, agreeing with the thermal expansion effect of common materials, but the Raman spectra from different experimental conditions are slightly different with each other at same temperatures. The difference between them has been explained by the local laser heating effect.

Raman (4000-95 cm–1) spectra of the recently identified magnetic geometric frustration material – deformed pyrochlore-structure hydroxyl cobalt bromide β-Co2(OH)3Br polycrystalline sample were measured using 10X and 50X microscopic objectives under different laser powers at room temperature. It is found that the obtained Raman bands at these experimental conditions are slightly different from one another. This phenomenon is caused by the so-called local laser heating effect and can help predict the temperature-dependent spectral behavior of β-Co2(OH)3Br around the room temperature. The Raman spectral experiments down to liquid nitrogen temperature (77 K) confirmed this local laser heating effect.

In this paper we propose a control scheme of electromechanical actuator with optical encoder feedback. Controlled object is the simplified model of a DC motor while feedback device is an optical encoder. Encoder model is established after analyzing its principle and signal characteristic. Many velocity estimation methods have been compared and the least squares fit filter is selected for our design because of its simple algorithm and capability of predicting velocity and position. Using these predictions as feedback, a variable structure controller based on exponential approach law is adopted in the actuator close-loop control. The relationship between system performance and encoder resolution is exposed. This scheme can be implemented easily with low cost and convenient interface. Its validity is proved by simulation results.

An approach for estimation to states of missile guidance based on predictive filtering is derived for the measurement process with high and low frequency noise. Analyze the influence of various noises on miss distance. Comparing with the extended Kalman filter, the simulation results indicate that this new method is able to improve accuracy of the guidance system with less estimation error.

An optical flow sensor is fabricated by using an optical navigation sensor as its core chip. The design process is detailed and an optical flow testing platform is designed to test its performance and calibrate its basic parameters. Then the optical flow sensor is introduced to the altitude-holding control loop of a cruise missile and a hardware-in-loop simulation is demonstrated. The simulation result verifies the sensor’s effectiveness in the low-altitude penetration.

Magnetic hysteresis yarn tensioner is a new-type component which is used in textile machinery for achieving automatic controlling. Its hysteresis damping characteristics of the torque is directly related to changes in the tension of the yarn. Hysteresis damping torque characteristics depends on the excitation voltage of the yarn tension and the magnetic storage of the hysteresis loop. In this paper, electromagnetic properties of the key components in the magnetic t hysteresis yarn tension were analyzed, and the outputting characteristics of magnetic hysteresis yarn hysteresis damping torque in different excitation voltage and speed had been obtained. The theoretical and experimental foundation of is provided about improving the uniformity of textile yarn and achieving the group control technology of Yarn tension.

Multi-layered biaxial weft knitted fabrics has excellent mechanical properties and formability. The performances of multi-layered biaxial weft knitted fabrics were compared with multi-axial warp knitted fabrics and plain weave fabrics to highlight the advantages of this novel fibrous assembly. The manufacturing method and applications of the developed novel fabrics were illustrated in details.

The Fe3+,La3+ co-doped polyvinyl acetate(PVAc)/titanium dioxide(TiO2) composite nanofibers were firstly prepared by combining sol-gel method and electrospinning process, and then calcined under 300°Cand 600°C separately. The effect of calcination temperature on structures, surface morphologies, crystalline state, elemental composition and photocatalysis activity were characterized by scanning electron microscope (SEM), atomic force microscope (AFM), X-ray Diffraction (XRD) , energy dispersive X-ray spectroscopy (EDX) and ultraviolet-visible spectrophotometer(UV-Vis) respectively. The SEM and AFM images showed that the nanofibers were randomly distributed to form the fibrous web, the diameters and surface roughness of nanofibers were obviously changed as the calcination tempreture increasing. The EDX analysis and XRD spectra indicated the percentage of C,O,Ti elements varied as the increase of tempreture and the formation of anatase crystal form TiO2 nanofibers under 600°C.The UV-Vis curves revealed strong adsorption to methylene blue under 600°C calcination.

With the development of modern technology, fiberglass composite materials are widely applied. The advantages of fiberglass reinforced composite materials are high strength and light weight. In order to produce a prefabricated fiberglass composite, a machine chart was drafted for weaving the 3D fiberglass fabric with five layers. The obtained five-layer 3D fabrics were composited with polyurethane matrix. Afterwards, the performance of the prefabricated composites was tested and the optimal ratio of fiberglass to matrix was determined by statistical analysis.

This paper presents an enhanced lift-off process for forming side electrode on the quartz –based double-ended tuning fork (DETF) resonator. In the case of fabricating quartz-based DETF, electrode pattern design is an important issue. Taking advantage of the piezoelectricity effect, a simple surface electrode can excite the flexural motion of the DETF, however it suffers from the large motional resistance. Proposed lift-off process can pattern excitation electrode on the side wall without using special photolithograph equipments. Experimental results demonstrated that the motional resistance can be reduced by several times by forming side electrode using proposed process.

The distribution of hoop stress calculated and simulated by Finite Element Method and theoretical calculation in this paper, when the hydrostatic pressure was carried out on the line pipe of Φ 762mm×31.8 mm API SPEC 5L[1] X70 longitudinal seams submerged arc welding(LSAW). The results of simulated by Finite Element Method were accord well with that of theoretical calculation, both of them shown that the hoop stress deviation between pipe inside surface and outside surface was nearly 40MPa, which was about 9% of the hoop stress of outside surface. Besides, the influence of the D/t(diameter-thickness ratio)on the hoop stress were also researched, which shown that the larger the value of D/t was , the fewer that influence on the hoop stress, when D/t=200, the deviation was less than 1%; Or else, the D/t may cause a great stress gradient in the direction of the thickness, even when the D/t=42, the deviation was up to 5%. So that, the effect of the d/t should be taken into account when calculating the hoop stress of pipe with D/t≤42. In other word, a new hydrostatic pressure formula for the heavy wall thickness pipe( D/t≤42) was put forward and adopted when calculating its hydrostatic pressure, that was P =c* Sh (Do2 - Di2) / (Do2 + Di2), where, c, specification coefficient; Sh, hoop stress; Do, outside diameter; Di, inner diameter.

Based on the analysis of chemical constituents and mineral composition, a new disposal method of alumina red mud added in cement stabilized macadam base was put forward. Through experiments of compressive strength, dynamic elastic modulus, splitting intensity and resilient modulus, mechanical properties of alumina red mud- cement stabilized macadam base and base performance affected by alumina red mud dosage were studied. Also, the strength formation micro-mechanism of alumina red mud-cement stabilized macadam mixture was explored by scanning electron microscopy (SEM). The results indicate that alumina red mud-cement stabilized macadam mixture has good mechanical properties; its early compressive strength, early splitting intensity, dynamic elastic modulus, resilient modulus are improved obviously with alumina red mud mixing; the mixing amounts of alumina red mud and cement are significantly affected mixture strength and the optimum mixing amount is respectively 10~12% and 5~6%; alumina red mud can promote cement hydration and hydrates generation. it not only is used as interstitial material among aggregates，also as binder closely linked aggregates through the spatial reticular structure formed by red mud and cement hydrates, which enhance mixture strength.

The electrochemical oxidation of wastewater from DDNP production was investigated using a boron-doped diamond (BDD) thin film electrode. The effects of operating factors such as cell voltage, interelectrode distance and additive NaCl have been studied. This study showed that the chemical oxygen demand (COD) reduction is most influenced by the applied cell voltage. Higher current densities resulting from higher cell voltages increase the formation of oxidative reagents resulting in an increased COD removal rate. The maximum COD removal was 57% after 210 min, with an energy consumption of 14.90 KWh·kg-1COD when cell voltage was 12V, interelectrode distance was 3cm and additive NaCl concentration was 1g·L-1. The use of BDD thin film electrode for the treatment of DDNP production wastewater appears commercially feasible.

The governing equations of flow of the second-order fluid with variable coefficients through concentric annuli with isometric ring slots on the inner cylinder under the cylindrical coordinate system were established. The governing equations were numerically solved by the finite difference method, the influence of slot width, slot depth, slot interval and slot number on velocity distribution is analyzed. The results show that slot width and slot depth is related with radial velocity, axial velocity and resultant velocity, slot interval is related with radial velocity, which is little related with axial velocity and resultant velocity, slot number is little related with radial velocity, axial velocity and resultant velocity.

To evaluate the influence of plasma power on the structural, electrical and optical properties of Al-doped ZnO (AZO) films, a set of polycrystalline AZO samples under different plasma power were deposited on glass substrates at room temperature. X-ray diffraction technique (XRD), four-point probe measurements and spectrophotometer were used to characterize these films. XRD shows that all AZO films have a hexagonal wurtzite structure with prominent (002) orientation. With the plasma power increasing, the grain size first increases and then decreases. The largest grain size of 23.6 nm in the films is obtained at the plasma power of 123 W. The average optical transmittance of AZO films is over 80% in the visible region. The lowest resistivity of 1.0×10-3Ω•cm is obtained under the plasma power of 220 W.

Antimony and tellurium were deposited on K9 glass via direct current and radio frequency magnetron co-sputtering. Antimony telluride thermoelectric thin films were simultaneously synthesized without post treatment. The influence of the sputtering power of Te and annealing of Sb-Te fabricated by magnetron sputtering were investigated. The maximum Seebeck coefficient of Sb-Te film was 212 μV/K which was obtained at the sputtering power of Sb 4W and Te 60W separately. When annealed at 300 °C, the electrical resistivity and Seebeck coefficient of the film are 6.67x104 S/m and 119 μV/K. The power factor increased to the highest value of 9.4×10-4 W/mK2 from 4×10-5 W/mK2 after post treatment of the as-deposited film.

The properties of the fiber material, which prepared from the high-performance heterocyclic polymer poly-p-phenylene-benzimidazole-terephthalamide (PBIA), were investigated. Poly-m-phenylene isophthalamide (PMIA) and poly-p-phenylene terephthalamide (PPTA) fibers were also studied, for comparison, under the same experimental conditions. Thermogravimetry(TG) and thermogravimetry coupled to Fourier transform infrared spectroscopy(TG-FTIR) were used to study the properties of these fibers. The results show that PBIA fiber has better tensile properties, thermal stability than that of PMIA and PPTA fibers. The onset degradation temperature of PBIA is the highest, namely 421°C in nitrogen. TG-FTIR provides information on the compositions of the pyrolyzates as well as their relationship to the structures of the polyamides. Analysis of the results indicates that a hydrolytic mechanism plays a leading role at lower temperature, and a homolytic mechanism is dominant at higher temperature.

In this paper, reverberation chamber high-frequency vibration-acoustic problem for an aircraft cabin is investigated with two methods. One is combining energy finite element analysis (EFEA) and energy boundary element analysis (EBEA); another is boundary element method by SYSNOISE. Comparison is performed between these two methods.

In the paper, the vector expression of cutting speed on the contact-points has been obtained by the coordinate transformation. The cutting speed is the contact-point position function which is correlated with contact-line in the process of honing gear. It is diverse along the direction of the tooth depth, so the surface texture of workpiece gear has a visible difference from the top to the root of the tooth. It is showed in the results that the surface roughness value of same tooth has further increscent differences with the increasing honing speed, and the surface of tooth is in the same quality.

Fire water monitor plays an important role in the fire fighting. A liqumatic fire water monitor with self-swing device was designed, the working principle and its components were also expounded in detail. The internal flow performance was simulated using fluent software, the influence rules on outlet velocity were analyzed by changing different angles of the monitor head and diameters of the monitor body. At the same time, the experimental tests were also carried out on the test rig. The simulation results accorded with the theory calculations in general. So, the rationality and accuracy of the designed fire water monitor was verified, and the relevant results can also provide a certain theoretical references for the design of other types of fire water monitor.

This paper analyses the material removal and surface forming mechanism of ultrasonic auxiliary gear honing. According to the Huygens principle of diffraction, a theory is proposed firstly that the ultrasonic waves transmit through the being honed gear in toroidal form, and the mathematical equation of the abrasive trace is built that expresses the relative movement between CBN abrasive and the gear surface. The equation is accordant with the experimental result. The paper concludes that the material removal of the gear surface depends on two factors, one is that CBN abrasives scratch the gear surface, and the other is that the gear surface vibrating itself along its normal direction impacts the abrasives.