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The spindle or spherical cobalt oxalate powders were prepared by conventional precipitation in the presence of pulsed electromagnetic field (PEMF). The morphology and phase structure were characterized by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The aspect ratio and surface fractal dimension of cobalt oxalate aggregate were calculated using Image tool software and Differential Box Counting (DBC) algorithm. The results indicate that the products prepared from ammonium oxalate and cobalt chloride give rise to the formation of β-CoC2O4∙2H2O. With the increase of pulsed time, the morphology of cobalt oxalate sample varies periodically from rod-like to spheroidic. For the sample treated for 60 s, the degree of sphericity is the highest. The surface fractal dimension is 2.096 and the corresponding fractal form is tight type.

Our goal was to evaluate how mechanical injury induced oleocellosis, and its discolouration and oxidative stress mechanism in Fengji Navel oranges (Citrus sinensis L. Osbeck) during previous storage. The results indicated that H2O2 content in mechanical treated fruit was higher than control. APX activity was higher than control during most of previous storage, but CAT, GR activities and ASA, GSH contents were lower than control, which showed GR activity and ASA, GSH contents might play an important rule in enhancing H2O2 to damage cell in mechanical treated fruit. Moreover, our study showed that chlorophyll content was enhanced, but total phenols content was not affected by mechanical during previous storage, which showed that discolouration was turning green but not browning at previous storage.

The boracic poly-aluminum-ferric-silicate (B-PSAF) coagulant was prepared by water solution co-polymerization method, which was synthesized from sodium silicate, aluminum sulfate, ferric chloride and sodium borate. In addition, the best molar ratio of boron and silicon was determined by single factor process. The micro-morphology and structure of B-PSAF were studied by scanning electronic microscope (SEM) and Fourier transform infrared spectrum (FT-IR). It has been studied the operation of B-PSAF as the flocculating agent, the dosage and its effects on the flocculability. Experiments show that B-PSAF is a good effective flocculant, which can be used to treat alkaline dyeing wastewater and it has the features of less consumption, rapid coagulation and high removal rate of CODCr.

Application of three-dimensional modeling software based on rhinoceros as well as V-ray for rhinoceros in metal packaging design is introduced. The paper conducts detailed discussion on computer virtual technology featuring double-sided metal material and bump graphic effects in the process of metal packaging design, providing effective methods for designing of such packaging container and virtual demonstration.

Microbial transformation of plant tubers for diosgenin production is an attractive clean method in industry. The purpose of this study was to evaluate the quality of the product obtained this way. Changes of saponins during the hydrolysis ofDioscorea zingiberensistubers byTrichoderma reeseiwere investigated. Four main saponins were isolated from the plant herbs. Sugar chains, which connected to the C-3 hydroxyl group in saponins, were cleaved stepwisely byTrichoderma reeseifrom the terminal sugar until the aglycone was released. Diosgenin-3-O-β-D-glucose was a byproduct in this process. While, in the petrol extract of the microbial hydrolyzate, only diosgenin was detected. Melting point, IR spectra and13C NMR spectroscopy were used to estimate the quality of the product. Diosgenin obtained from bioconversion showed similar characteristic to that from acid hydrolyzation, confirming microbial transformation was an effective method for diosgenin production.

Based on the fact of low single seed plant rate, high seed damaged rate and low seed adaptability for conventional and mechanistic precision seed-metering device, a new belt type of seed-metering device was designed (patent No.20101020638.7). both of the 1/4 spherical shape and its size was first established by analyzing the working process of the seed-metering combination the material character of the tested corn seed, and the structure size 6mmX6mm of the seed scoop of this type of seed-metering was then determined by the frame test in agricultural lab, which was tested to own the good work performance. At last, the working adaptability tests were operated, the conclusion showed that the following character indexes were single seed plant rate 98.6%, repeated plant rate 6.3%, leakage plant rate 0.8% and seed damaged rate 0.05% when the size of seed-scoop is 8mmX12mm and the belt speed is1.05 m/s.

About the separation methods of the traditional Chinese medicine components, there are common difficulties like time-consuming and compositions exist cross. Highly efficient way of separation is urgently needed in chinese medicines. The experiment adopted a better and specific 2-hydroxy-3-carboxy-N,N,N-trimethyl-propyl chitosan magnetic microspheres and separated the active anti-aging ingredients from Rubus chingii Hu. In this experiment, Fe3O4 nanoparticles were prepared by coprecipitation method. Microwave synthesis method changed the property of the surface of chitosan, we prepared 2-hydroxy-3-carboxy-N, N, N-trimethyl-propyl chitosan. And we prepared 2-hydroxy-3-carboxy-N,N,N-trimethyl-propyl chitosan magnetic microspheres by microwave synthesis. Discussed the anti-aging ingredients separating condition of 2-hydroxy-3-carboxy-N,N,N-trimethyl-propyl chitosan magnetic microspheres by UV spectrophotometry results. Ultraviolet spectrum showed that characteristic peaks of falconoid components and anthraquinones components. Chemical identification experiments show that separated samples only contain falconoid components and anthraquinones components. Using this material to separate active ingredients of Rubus chingii Hu will greatly shorten the time than traditional separation method, the components will be more purer. The results show that using this material to separate anti-aging ingredients of Rubus chingii Hu is efficient, concentrated, stable and reliable.

In the homogeneous system, the low molecular weight Chitosan is obtained by H2O2 oxidation degradation method. Acetyl Sulface reacted by the mixture of Acetic Anhydride and Concentrated Sulfuric Acid at equal proportion is the reagent. low molecular weight Chitosan being as raw materials, Vulcanized Oligomer Chitosan is sulfonated with good water-solubility and high sulfur content under certain conditions. It has been tested for the influence of the usage of sulfonated reagent, reaction temperature and reaction time on Sulfer content. The best condition for preparation Vulcanized Oligomer Chitosan is 5ml of Acetyl Sulface with the reaction temperature of 25°C and time of 5 Hours. It’s a new potential heparin with around 100 nm particale size tested by spectral analysis and SEM measurements, which could be a new reagent in other fields.

Internal tides generated by the interaction of the barotropic tide with bottom topography are studied by using an analytical solution. Tide-topography resonance takes place when the wavenumber of the truncated sinusoidal topography is equal to that of one baroclinic mode. The minimum amplitude of the resonant mode increases from the center of the domain to both sides of the topography; while the maximum keeps the same. Amplitudes of the internal tides and mode conversion rate are analyzed as a function of the length and wavenumber of the topography. For non-resonant modes, the amplitudes are weak and vary periodically with the extending of the topography, and are exactly zero when the length of topography is integral times of the mode-1 wavelength. For resonant modes, the amplitudes increase with the length of the topography. For each internal tide mode, there is a response zone, where the amplitude for one mode is obviously larger than other baroclinic modes. The response zones for high modes are wider than those for low modes. Mode conversion rate is obviously high when the wavenumber of the topography is equal to that of the baroclinic modes; otherwise it is almost zero. Furthermore, mode conversion rate for small topography wavenumber is more than that for large topography wavenumber with the same number of the sinusoidal topography, and is less with the same topography length.

Here the process of internal tide generation over idealized (sinusoidal) topography was investigated using numerical techniques, in which the barotropic-to-baroclinic energy conversion was discussed. The result shows that when the wavenumber of the sinusoidal topography, ktopo, is equal to the horizontal wavenumber of the m-th baroclinic mode km, the conversion from the barotropic tide to the m-th baroclinic mode is enhanced with the increase of topography length; When the wavenumber of the sinusoidal topography is not equal to horizontal wavenumbers of any baroclinic modes, ktopo≠km(m=1,2,...), conversion from the barotropic energy to baroclinic modes is decreased with the increase of topography length. Furthermore, it shows that in resonance case, the phase of the perturbation pressure gradually agrees with the phase of the truncated sinusoidal topography, and the conversion rate is always positive over the topography, thus the baroclinic mode which matches with the wavenumber of the sinusoidal topography persists in absorbing energy from the barotropic tide, and the conversion rate is increased.

A novel catalyst for the copolymerization of CO2 and cyclohexene oxide(CHO) was prepared by using BTE and ZnCl2. The zinc complex showed catalytic activity for the copolymerization. The obtained copolymer was characterized by IR and NMR. Effect of reaction time on copolymerization was investigated.

3D ink-jet printing is regarded as the ideal manufacturing technology for Heterogeneous Object(HO) materials, but this technology is much restricted by the high requirement on idealized materials, high forming cost and imperfect modeling and layering technology for HO. To solve these problems, a virtual 3D ink-jet printing system for simulation of HO fabrication is developed in this paper. Since the physical model is replaced by the digital model, the potential risk will be avoided effectively and it will result in higher product quality and much lower manufacturing cost. Finally, examples of the virtual formed prototypes are given.

By fluid analysis for the finite element models of "S"-shaped and straight waterways with ANSYS, through thermal analysis for the finite element models of the function blocks with and without holes cooling after flow analysis, by comparison of the temperature field, function blocks with hole deformation is narrowed, the product quality can thus be improved.

Nowadays Static Synchronous Compensator (STATCOM) has gradually become one of the representative techniques in the field of dynamic reactive power compensation in the power distribution system. This paper analyzed the topology and the voltage imbalance problem of the up and down capacitors on DC side of the three-phase four-wire STATCOM. In allusion to the imbalance problem of neutral point, a novel control strategy based on the control of zero-sequence current was proposed. By the triple close-loop control strategy, the STATCOM can achieve great control accuracy and dynamic performance. Simulation result proves that the proposed control method is effective.

Nonlinear loads generate a large amount of characteristic harmonics , deteriorate the power quality of power distribution systems in Advanced manufacturing enterprises. In this paper a novel hybrid active power filter is proposed which consists of a series thyristor switched filter (TSF) and small rated shunt active power filter(APF). TSF is tuned at fifth and seventh order harmonic frequencies. Consequently APF compensates for third and other order harmonics, unbalance current and reactive power. A new control method based on PHC strategy is presented for APF. The device has already got an application in one of the transformer substations of a automobile factory. It’s revealed that the proposed device can improve the power factor , reduce the harmonics injection and enhancement power quality of the power distribution systems.

A high efficiency simultaneous cellulose degradation and hydrogen production strain X9 was obtained from the screening of the 125 strains of fermentative hydrogen production bacteria which were isolated from a continuous stirred-tank hydrogen production bioreactor (CSTR) with LM-1 and microcrystalline cellulose (MCC) medium and improved Hungered technique in this study. X9 was confirmed a new category by analyzing the results of biochemical and physiological test, shape character, 16S rDNA sequencing and phylogenetic, and then analysis characteristics of growth, culture parameters, the effects of components of medium on growth and ability of hydrogen production, the optimum technological parameters have been determined from orthogonal experiment and single factor test. Finally, X9 achieved maximum specific hydrogen yield of 4.9mmol/g with MCC under the optimal conditions.

The effects of sodium nitroprusside (SNP) treatment on the disease resistance and storage quality of citrus fruits were investigated through inoculation and storage. The results showed that SNP treatment could effectively reduce the disease incidence and lesion diameter of satsuma mandarin inoculated with Colletotrichum gloeosporioides Penz. during storage. Compared with control, weight lose rate degraded, but soluble protein, ascorbic acid (ASA), reducing sugar content and SSC/TA ratio increased in SNP treated fruits. 50 μmol•L-1 SNP treatment had the better effect than 30 and 100 μmol•L-1 SNP treatment.

According to the working characteristics of the hydrodynamic retarder, the hydrodynamic retarder D300 is chosen in this research. Based on three-dimensional flow theory, the internal temperature fields of hydrodynamic retarder with different liquid-filled ratios of 100%, 75%, 50%, 25% are numerically simulated. The standard k-ε model is chosen as turbulent model for calculation. The SIMPLEC algorithm is chosen as velocity-pressure coupling algorithm and the second order upwind scheme is used as discrete method. The mixture multiphase model is used to calculate the unsteady gas-liquid two-phase flow in the condition of partial charging. Through simulating and analyzing, it provides an important theoretical basis for the heat exchange of the hydrodynamic retarder at different gears.

In this paper, graphite oven atomic absorption spectroscopy was adopted to determine typical metals contents, iron (Fe), aluminum (Al), chromium (Cr), in engine lubricating oil for a rapid evaluation about engine wearing conditions. Samples were made into translucent micro-emulsion by adding Tween 80 and 1% nitric acid solution, and then Fe, Al and Cr contents were determined. The recovery rate of standard addition method was achieved as high as 95.3% to 101.1%, and relative standard deviation (RSD) of six times parallel tests were all less than 3%. The results indicated that the adoption of atomic absorption spectroscopy to predict engine wearing condition acquired the following advantages: high sensitivity, simple operation, pinpoint accuracy and excellent reproducibility.

By now, it is hard for an effective determination of the engine abnormal sound according to the existing auscultation method based on human experiences and diagnosis aided by instruments. For this reason, the author presented an innovative method that was by the using of atomic absorption spectroscopy technology for a rapid determination of the engine crankshaft bearing abnormal sounds. Major metals contents (Cu and Pb) in 20 batches of Audi A6 engine lubricating oil were detected by atomic absorption spectrometry. Samples were taken from the oil of mileages from 5000km to 69000km and 3000km intervals. Then the databases of main metal contents of different driving miles were built within the same vehicle type. This study showed that the main metal contents were fluctuating with the increasing of driving miles within certain range. For the practical application, we built a connection between engine abnormal sound faults and the major metal contents in the engine lubricating oil. By comparing the metal contents in problem engine with the established contents changing trends chart, we could get a rapid determination about the engine abnormal sound fault without disintegration of the car. To sum up, the achievements of this study helped to reduce vehicle maintenance costs and improved the fault diagnosis accuracy in abnormal sound of engine crankshaft bearing.

Through the discussion of main shortages of the high-speed electromagnetic valve used in electronic fuel injection system, the author introduced a new design thought of fuel injector based on 2D technology. Axial displacement of controlling valve was used to control the volume of gushing oil, while radial revolution of spool valve was used to change the time of injection. Additionally, mathematic modeling and MATLAB simulating indicated that, the injector designed based on 2D technology acquired the advantages of quick response and also realized the ideal shape of fuel injection rate.

The 2μm thick TiN coatings were deposited by arc ion plating on YW2 cemented carbide substrate, and the system of TiN/YW2 was treated with cryogenic treatment at -196°C for 30 hours. The change of the Rockwell indentation's morphology of the system (the form and density of cracks, the spalling state of the coating)before and after the treatment were investigated by means of the Rockwell hardness tester. With metallurgical microscope and SEM, the change of the microstructure of the substrate and its influence on the fracture toughness of the system were investigated. The results show that after the treatment, the density of the radiated cracks in the substrate were obviously reduced, but the main cracks hadn’t any change, the spalling of the TiN coating along the indentation was lightened. After the cryogenic treatment the dispersed granular γ phase obviously decreased or even disappeared, the pores became smaller and the microstructure of YW2 became more compact，and the microcracks were merged during the cryogenic treatment. These are beneficial to improve the fracture toughness of YW2 substrate and the coating/substrate system.

New inorganic pigments Ce0.95ZrxPr0.05-xO2(x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) based on CeO2-ZrO2-Pr6O11solid solutions were synthesized by low-temperature combustion synthesis (LCS) method using citric acid as a reductant and metal nitrate as an oxidant. The pigments are CeO2solid solutions doped with praseodymium and zirconium ions, and display colors ranging from dark brown via brick red to bright cream. The prepared pigments were characterized by X-ray powder diffraction, transmission electron microscopy, ultraviolet-visible absorption spectroscopy and colorimetrical measurements. Results show that cubic fluorite structure solid solution of 100 nm Ce0.95ZrxPr0.05-xO2particles can be obtained at 1000 °C. There was an effective absorption of visible blue and green in 600 nm, which is originated from the shift of charge transfer band in CeO2by doping of zirconium and praseodymium ions. Effective red hue was obtained for Ce0.95Zr0.02Pr0.03O2composition, which exhibited better L*, a*,and b* values (57.64, 23.83 and 23.78). The coloring mechanism is based on the introduction of an additional electronic energy level of unpaired 4f electron of the lanthanide ion into the cerianite forbidden band. Furthermore, the doping of Zr in Pr-CeO2system raises the slope of the absorption edge with a blue shift resulting in enhanced lightness. The prepared pigments were prospective to be alternatives for toxic pigments used in coloration of plastics.

Well-aligned ZnO nanorod arrays had been successfully prepared by using hydrothermal methods. XRD and SEM analysis showed ZnO nanorod arrays had well orientation along the [0 0 1] direction of ZnO nanorods. The length to diameter is biggest among these samples and is about 25 when solution concentration is 0.8mol/l. The UV emission caused mainly by exciton combination. Furthermore the formation mechanism of ZnO nanorob arrays was studied in detail.

Transparent ZnO:Al films deposited by RF/DC magnetron sputtering in room temperature are annealed under gaseous ammonia ambient and air ambient, respectively. The characteristics of ZnO films are examined by XRD, SEM, Hall measurement and optical transmission spectra. The XRD and SEM analysis shows that both films are crystallized in the wurzite phase with a preferential orientation along the c-axis and have a smooth dense surface. Hall measurement results indicate ZnO:Al films annealed under ammonia ambient convert to p-type conduction with the high carrier concentration of 8.3×1018 cm-3. Optical transmission spectra show a high transmittance (~85%) in the visible region.

In this paper, research was focused on the synthesis of a new efficient coagulant, boron -containing poly-silicate zinc (PSZB).The effect of the SiO2 concentration, Zn/Si molar ratio, B/Si molar ratio, activation time on flocculation properties were examined in detail. And the optimal preparation conditions were determined. At the same time, the industrial wastewater and life wastewater were treated for the properties test. The experimental results showed that the flocculant had good stability and good effect. It is a kind of good performance of flocculants.

It was investigated that the effect of electric pulse modification (EPM) on the hot tearing of Al-5%Cu-0.8%Mn alloy. The results indicate that hot tearing tendency of all samples can be reduced treated by electric pulse with different parameters, moreover, hot tearing stress of alloy with EPM was enhanced 3 times or so than that of samples without treatment. Decreasing the quantity of eutectic in grain boundaries, decreasing the end-solidifying temperature of the alloys, and refining the grains are main causations for increasing hot tearing resistance of Al-5%Cu-0.8%Mn alloy by electric pulse modification.

It was investigated that the effect of electric pulse modification (EPM) on the hot tearing of Al-5%Cu-0.8%Mn alloy. The results indicate that hot tearing tendency of all samples can be reduced treated by electric pulse with different parameters, moreover, hot tearing stress of alloy with EPM was enhanced 3 times or so than that of samples without treatment. Decreasing the quantity of eutectic in grain boundaries, decreasing the end-solidifying temperature of the alloys, and refining the grains are main causations for increasing hot tearing resistance of Al-5%Cu-0.8%Mn alloy by electric pulse modification.

As the development of carbon diocide sensors and communication technology, the method for monitoring the concentration of carbon dioxide is more and more advanced, especially the traditonal methods have the disadvantage of the low accuracy and inconvenience on use. This paper puts forward a wireless sensor networks based on nRF401 chip and the method of the signal transmitting. Through the application of wireless technology, the MCU could send the carbon diocide concentration data from the carbon diocide sensor which is based on the NDIR technology to the process module, and the system could achieve the distant measurement of the carbon diocide displayed on the LED. Comparing with wire monitor system, wireless monitor system omits linking lines and it has good application prospect.

Li-doped ZnO thin films were grown on quartz substrates by radio frequency magnetron sputtering and In-situ annealing. The structural, electrical and optical properties of Li-doped ZnO films strongly depend on the annealing oxygen pressure. XRD and AFM analysis indicate that the ZnO films possess a good crystallinity with c-axis orientation, uniform thickness and dense surface. Optical transmission spectra show a high transmittance (~85%) in the visible region. Hall measurement demonstrates that ZnO films have p-type conduction with a Hall mobility of 5.0 cm2/Vs, resistivity of 0.97Ωcm and carrier concentration of 1.60×1017cm-3when annealing oxygen pressure is 1Pa.

A catalyst of BTPD-Zn (BTPD= N,N’-Bis(2-thiophenecarboxaldehy) o-phenylenediamine) has been found to be active toward the copolymerization of cyclohexene oxide and carbon dioxide, and a kind of good biodegradable material named poly(cyclohexene carbonate) is prepared with turnover number of 105.8 in 100°C. The molar fraction (fc) of polycarbonate in copolymer is 96%. The obtained copolymers were characterized by IR and NMR.

The optical surface defects have a significant impact on functions and reliability of the whole optical system. In recent years, with the great attention on research of large-scale high-power solid-state laser device at home and abroad, the detection of optical surface defect has also been highly valued. Through continuous exploration, defect detection technology has made some achievements, but there are still some urgent technical problems to be solved. In this paper, the technology situation of optical surface defect will be summarized in two aspects: the surface cleanliness and surface flaws. Moreover, the technical difficulties and the problems which are currently facing will be analysis.

Inertial confinement fusion has been concerned in the year 1963. It was from the 1970s that China began to study inertial confinement fusion devices, and got lots of achievements in recent decades. The development of Inertial Confinement Fusion has an important and special meaning, whether to the national economy, military applications or for basic research. This paper comprehensively discussed the process of several large-scale ICF laser devices, the major technical indicators and the main experiment related to the devices.

In this paper, a kind of Mg, Nb co-doped multilayer piezoelectric ceramic is prepared and a non-contact accurate testing method is introduced. Using Pb(Mg1/3Nb2/3)O3- Pb(Ni1/3Nb2/3)O3- Pb(ZrTi)O3 low temperature co-fired ceramics powder and 90/10 Ag-Pb internal electrodes, the sample is prepared with tape casting processing method and low temperature co-fired technique at 960°C. Based on non-contact method, the piezoelectric constant, butterfly curve, and temperature characters are tested. Experiments show that non-contact method is more accurate for d33 testing. The effect of mechanical load on piezoelectric performance is also investigated. Under external mechanical load, switching polarization (Ps) and remnant polarization (Pr) increase respectively. Mechanical load press is also favorable to dominate the temperature rise of the piezoelectric device.

Nanocrystalline ZnO powders have been synthesized by a novel combustion synthesis method using glycine and urea as mixed fuels and zinc nitrates as oxidant. The as-synthesized ZnO powders are characterized by DSC, XRD and SEM. Results show that the as-synthesized ZnO powders show well crystalline with hexagonal crystal structure and purity without any other impurities and the particle sizes are about 50~70nm calculated by the Scherrer formula.