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In this paper, shaped titanium silicalite-1 (TS-1) zeolite catalysts from spray drying and extrusion were prepared and characterized by X-ray diffraction (XRD), infrared spectroscopy (FT-IR), nitrogen physisorption and laser diffraction techniques. The typical TS-1 MFI framework structures were both well retained during the shaping process. However, the extrudates gave dramatically decreased specific surface area, total pore volume and relatively poor catalytic performance in cyclohexanone ammoximation compared to spray samples and powdered TS-1, indicating that the spray method may be better choice for the reaction. Moreover, the stability and reusability of the spray shaped catalyst was evaluated by performing consecutives batch ammoximation runs with the same catalyst sample. After the fifth batch, it observed well stability of catalytic activity and particle size distribution.

The effects of poly (vinyl pyrrolidone)(PVP) on dispersing carbon black (CB) particles were investigated by measuring Z-average particle size, Zeta potential and centrifugal stability of CB dispersions. Addition of PVP in a dispersing medium significantly reduces the size of suspended CB particles, especially in water. The dispersing efficiency of PVP was found to have been enhanced by adding an anionic surfactant, sodium methylenedinaphthalene disulphonate (NNO) in the aqueous media. The particle size of CB dispersed with PVP and NNO was 175.7 nm, significantly smaller than that dispersed with PVP and sodium dodecyl sulfate (SDS). The performance of PVP-encapsulated CB particles and that of PVP-adsorbed CB particles were also compared. The particle size and Zeta potential of PVP-encapsulated CB particles were similar to those of PVP-adsorbed CB particles using ultrasonic method, but the centrifugal stability of PVP-encapsulated CB dispersions was significantly improved. The relative absorbency of PVP/CB dispersions was increased from 42.0% to 63.7%. However, the PVP-encapsulated layer can be destroyed by prolonged ultrasonic treatment because the ultrasound over a long period of time can not only break up the flocculation bridge in the crosslinking matrix of PVP, but also flake off the PVP shells on the surface of CB particles.

One-dimensional (1D) ZnO nanorods with different shapes and high aspect ratio were successfully synthesized using a cetyltrimethylammonium bromide (CTAB)-assisted or sodium dodecyl sulfate (SDS)-assisted hydrothermal process at 90°C for 5h. The surface morphology and structure of nanocrystals were characterized by FE-SEM and XRD. Experimental results showed that the typical morphology of ZnO crystals grown with additive of CTAB was pencil-like rods, while the ZnO crystals grown with SDS showed needle-like rods. The gas sensors had been fabricated using 1D ZnO powders to examine the response towards 40ppm NO2 in the range of operating temperature from 150 oC to 450 oC. Compared with needle-like ZnO crystals, the NO2 gas sensor based on pencil-like ZnO nanostructure had better selectivity at the same gas concentration.

The problems of compacted loess roadbed utilization are closely related to the characteristics of compacted loess and long-term vehicle loads. According to the characteristics of compacted loess in different degree of compaction, the distribution and deformation change rules of the dynamic stress under dynamic load are studied through the finite element program numerical analysis of vehicle loads roadbed dynamic response. The data is acquired by field test and laboratory experiment. In lighting of the influence of the subgrade deformation by degree of compaction and pavement structures, the influence models are given which are used for estimating the roadbed vertical displacement in different conditions.

In this work, a laminated microstructure-plate electrically heated micro evaporator was proposed. The effects of microstructure types on the evaporation efficiency of electrically heated micro evaporator under different input voltage values and flow rates of water were investigated. It was indicated that the triangular microstructure plate presented the best evaporation efficiency regardless of the change of input voltage and feed flow rate. The nonuniform-distributed microchannel plate presented better evaporation performance than that of uniform-distributed microchannel plate, while the triangular microstructure plate presented higher evaporative performance than that of rectangular microstructure plate.

The paper introduces the structure and functional modules of the cutting tools information integrated system technology. We can manage the information on cutting tools efficiently by using the system. According to process feature we may select the appropriate cutting tools and the optimized cutting parameters .The system has the advantage of good generality, flexible application and fine opening. By using it, the efficiency of selecting tools and cutting parameters can be greatly improved.

Using ultrafine carbon black (CB) dispersions to dye cotton fabrics back is feasible through an exhaustion procedure. The effects of CB particle size, the type of dispersants, electrolyte concentration and cationic modification of cotton on the colour yields of CB dyed cotton fabrics have been investigated. CB particle size ranging from 130nm to 200nm is appropriate to achieve a deep black shade in cotton fabrics. Cationic dispersant improves the K/S values and wash fastness of the CB dyed cotton fabrics. However, caution should be exercised in adding electrolytes to CB dispersions. Cationic modification of cotton is an effective method to achieve higher K/S values of CB dyed fabrics. It is desirable to dye cotton fabrics with ultrafine CB particles instead of with sulfur dyes and reactive dyes.

By studying the design theory of the mobile police station (MPS), the dynamic model of the MPS basic computing has been built then a novel MPS is designed. This kind of MPS, which consists of battery, chassis, body and electrical system, uses electric vehicle as the carrier and in combination with police needs is equipped with a variety of police equipment to meet the needs of establishing a modern police. The vehicle performance test has been done. The results prove that the performance of the MPS has reached the technical level of the Ministry of Science and Technology, showing the vehicle design is reasonable, and the matching calculation results of the electrical system parameters are basically the same as the experimental results.

In the light of heavy seismic landslide disasters in the valley city of loess area, 104 typical loess landslides caused by the 1654 Tianshui(Ms 8.0), 1718 Tongwei(Ms 7.5) and 1920 Haiyuan(Ms 8.5) earthquakes were studied, main landslide type and basic characteristics of seismic landslide in the valley city were analyzed. The landslides in the valley city of loess area are divided into three types: homogeneous loess landslide, loess interface landslide and loess-mudstone cutting layer landslide. Through the investigation and analysis of earthquake risk, the suggestion about the 22 dangerous landslides in Tianshui is given. The study is expected to supply scientific basis for seismic landslide disaster prevention and reduction in valley city of loess area.

This paper presents a novel strategy for synthesis of carbon nanomaterials using the Cstaple biomaterials – starch as the starting materials. The carbonhydrate were vaporized by arc under helium, which leads to a large amount of monodispersive carbon nanoballs with range of 30-70nm in diameter. In addition to carbon nanoballs, some carbon nanocapsules were occasionally observed in products. Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were employed to characterizing products. The growth mechanism of carbon nanoballs is discussed briefly in terms of the precursor composition and process parameters.

Here we reported that the Si-O-C nanoballs (SCONBs) were yielded from polyorganosiloxane, polydimethylsiloxane, by chemical vapor deposition (CVD) method. The composite nanoballs with a range of diameters from 50 to 200nm were composed of silicon, carbon and oxygen based on analysis of EDX. At the transmission electron microscope(TEM) and scan electronic microscope(SEM), two populations of nanoballs were found: around 200nm and 500nm. X-ray diffraction patterns demonstrated that the nanoballs were dominatingly amorphous. Temperature played an key role in size distribution of Si-O-C nanoballs, and the 850–900°C temperature range was typical for nanoparticles growth via CVD.

In order to study the stability of layered rock mass, a shear failure criterion for layered rock mass is presented and its program is compiled in C language. The shear failure criterion consists of two parts: firstly, four empirical expressions are suggested in which shear strength parameters vary with the direction; secondly, a pilot calculation method is developed to judge whether a shear failure plane in layered rock mass occurs or not and give its occurrence under three dimensional stress condition. A triaxial numerical experiment on layered rock mass is designed to test the shear failure criterion, and its results reflect the characters including obliquity effect, confining pressure effect and failure mode which conform to the previous triaxial tests.

The electromagnetic characteristics of rock and ore play an important role in resources, engineering and environmental fields. The high frequency part of rock electrochemical impedance spectroscopy can reveal its crack characteristics according to the test results and rock physical model and equivalent circuit. The mathematical foundation of high frequency part of rock electrochemical impedance spectroscopy is studied, and the ideal Nyquist figure is obtained from that, and the response characteristics of rock electrochemical impedance spectroscopy volume arc are been proofed. It provides the theory basis for further study rock electrochemical detection technology.

The poly(phenlene sulfide)(PPS)/carbon nanotubes (CNTs) composite was prepared by plastic pressure moulding of mixture of PPS and CNTs mixed by ball mill. The structure, elcctrical conductivity and mechanical properties of the composite were studied in detail. The effect of content of CNT on mechanic properties and conductivity of composite was carried out, repectivly. The SEM characterization indicates that CNTs were dispersed uniformly in the PPS matrix, which leads to a remarkable improvement in mechanical properties of composite. Compared with the those of neat PPS, both the tensile strength and impact strength of the composite increase with content of CNTs. and the addition of CNT increases the conductivity of the composites dramatically.

Single-walled carbon nanotubes (SWNTs) have been successfully prepared from starch by arc discharge technique. The SWNTs products were characterized by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The growth mechanism of the SWNTs was discussed in terms of the starch. The results demonstrate that starch is one of the suitable precursor for making SWNTs by arc discharge method.

In view of the significant failure modes of formwork-supporting system and reinforced- concrete member, the reliability analysis model of time-dependent system affected by human errors during the construction of typical multistory reinforced-concrete buildings was developed. Human Reliability Analysis (HRA) method was applied to simulate the error rates and error magnitudes of the reinforced-concrete members and the formwork-supporting system, and human reliability models were developed, two cases for error-free case and error-included case were considered. Furthermore the check emphasis of formwork-supporting system was pointed during multistory building construction.

According to the character of the trans-critical CO2cycle, this paper develops the theoretical model of the gas cooler using the distributed-parameter method. At last, it optimizes the gas cooler. The comparison between the simulation and the experiments indicates: under different inlet temperature of cooling water, high pressure and mass flux of the refrigerant, the maximum deviation between the simulation and the experimental results is 5.6%, 10.1% and 19.7%,respectively. The optimal results indicates: when the refrigerant inlet is 8MPa and 93°C，and the cooling water inlet is 15°C，it is propitious to the inner heat exchange of the gas cooler using the four pipes of φ6mm×1mm, and the total heat exchange area of 1.1 m2.

On the basis of analyzing the properties of the Camellia oleifera peel and seed, for the purpose of solving the problem of the separation of peel and seed, a device has been designed based on the aerodynamic principles. The single factor experiment has been carried out to research how the feeding angle, feeding height, fan inclination and fan height can influence the seperation. The result shows that the feeding angle has a significantly effect on the separation, the suitable angle is 40°; the feeding height has a significantly effect on the separation; when the feeding height is 200mm, the peel in the seed zone is the least, but the seed in mixing zone is the most, when the feeding height is 300mm, the seed in the mixing zone is the lesat, but the peel in the seed zone is the most, so in the actual production, the feeding height need to be comprehensive considered; the fan inclination has a significantly effect on the separation, the suitable inclination is 15°; the fan height does not have a significant effect on the separation.

ZnS nanoparticles with Mn2+doping (0–2.5%) were prepared through a simple chemical method. The nanostructures of the prepared undoped ZnS and Mn2+-doped ZnS:Mn nanoparticles had been characterized by X-ray power diffraction (XRD), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), photoluminescence spectra (PL) and UV–vis absorption spectra. The mean size of the particles was found to be approximately 3-5 nm through XRD measurements, TEM and the UV–vis absorption spectra. It was found that the Mn2+4T1→6A1emission intensity of ZnS:Mn nanoparticles was significantly enhanced with the increase of Mn2+concentration, which arrived a maximum value when Mn2+initial doping concentration was 1.5%. Continue increasing the Mn2+concentration, namely more than 1.5%, the Mn2+4T1→6A1emission intensity became weakened. And the resultant ZnS:Mn nanoparticles exhibited high efficiency for degrading methylene blue under UV light irradiation.

In this paper, the effects of organic acid radicals on degradation of Orange II in UV-Fenton system with hydroxyl-Fe-pillared bentonite as catalyst were studied in detail. The results showed that the rate constants of UV-Fenton reaction will decrease when the system contains sodium citrate or sodium malonate. While the rate of Orange II degradation in UV-Fenton system could increase up to 33.3% and 41.7% when EDTA and sodium oxalate were present, respectively. As the additional TOC of EDTA is higher than sodium oxalate, adding sodium oxalate is a more promising enhanced method for Orange II degradation in UV-Fenton system. The rate of Orange II degradation could increase 25%, 42% and 175% when the concentrations of additional sodium oxalate increased up to 0.1 mM, 0.2 mM and 0.4 mM, respectively.

To enhance multilayer pressure vessels’ load bearing capacity, the paper presented a kind of split type compound vessel which employed split, shrink-fit and autofrettage techniques simultaneously. The vessel consists of a split layer made of sintered carbide, and an outer two-layer whole cylinder treated with autofrettage and shrink-fit. The mathematic model for the optimization design of the split type vessels was build based on stress analysis of each layer. In the model, the wall thickness of compound vessels is taken as an objective function; thickness of each layer, shrink-fit pressures, and the elastic-plastic radii of autofrettaged two layers are the design parameters; that Tresca stress of each layer equals to its design stress is constraint. An example was optimized. The results show that no additional strength was wasted in any of the layers at the optimum, and the vessels’ load capacity was far beyond the yield stress of outer whole cylinder.

The insufficient information about the mechanism of EDM process affects decision-making related to operation, parameter adjustment, and automatic control. Without a thorough understanding of the process dynamical features, it is difficult to determine a suitable model to describe such processes. This research employs the chaotic analytical techniques to determine the level of complexity of an EDM process; the correlation dimension method. With the understanding of the process complexity and its composition by correlation dimension analysis, a well-defined model is proposed. Finally, by using this model structure and size, an online time-varied predictive model was developed and verified by another experiment.

A novel and practical route for preparing carbon coating metal nanomaterials using polyvinyl alcohol as the starting materials was presented. Carbon coating iron nanoparticles can be effectively synthesized by carbonizing polyvinyl alcohol using Fe as catalyst in hydrogen flow. The carbohydrate was carbonized in a controllable way that leads to a large amount of carbon coating iron nanoparticles. Transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) and thermogravimetric analysis (TG) were employed to characterizing nanomaterials. The growth mechanism of carbon coating iron nanoparticles is briefly discussed in term of composition and structure of precursor.

A novel and practical route for preparing carbon nanocapsules using biomass – starch as the starting materials was presented. Carbon nanocapsules can be effectively synthesized by catalytic carbonizing starch in hydrogen flow. The carbohydrate was carbonized in a controllable way that leads to a large amount of carbon cages nanoparticles under Fe catalyst. Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were employed to characterizing carbon nanomaterials. The growth mechanism of carbon nanocapsules is briefly discussed in term of composition of precursor.