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In order to meet the requirements of the use of aircraft, improve mechanical properties of pavement concrete, the steel fiber mixed basalt hybrid fiber reinforced concrete technical route was proposed, by using the method of orthogonal experiment, steel fiber with 1.2%,1.5%,1.8% these 3 volume fraction and basalt fiber in 0.05%,0.1%,0.15% these 3 volume fraction mixed, research the rules of its effect on the performance of airport pavement concrete.

To understand the effect of a single overload on the fracture behavior in welded joints, the stress and strain field at the crack tip in a safe-end dissimilar metal welded joint in nuclear pressure vessel is simulated and analyzed by using the elastic-plastic finite element method in the paper, in which the mechanical heterogeneity in welded joint is emphatically considered. The investigating results indicate that the tensile plastic strain at crack tip increases, but the tensile stress decreases as a single overload increases, and the influence of a single overload on tensile strain is larger than one on tensile stress, which provide a theoretical basis for quantitatively estimating the crack growth rate of environmentally assisted cracking in the welded structural material of pressure vessel and piping in the nuclear power plant.

Our goal was to produce a complex inorganic polymer flocculant containing poly aluminum ferric chloride (PAFC) from blast furnace dust. The optimum reaction conditions to achieve high extraction efficiency of iron and aluminum were obtained through a series of batch experiments. PAFC was synthesized by controlling the hydrolysis conditions of iron and aluminum. Extraction efficiency of iron and aluminum oxides from blast furnace dust was affected greatly by reaction parameters such as temperature, time and hydrochloric acid consumption. The dissolution rate of iron was 67.61% and the dissolution rate of aluminum was 12.35% under the optimum reaction conditions (100 °C, 3 hours, and and the mixing ratio of the blast furnace dust to the hydrochloric acid is 1:3). To neutralize the pH and then synthesize PAFC, a solution of Al (OH)3 was added to the dissolved blast furnace dust, and the mixture was hydrolyzed at 60~70 °C for 4 hours. The prepared complex inorganic polymer flocculant proved to be effective in removing turbidity. The turbidity removal ratio for kaolin simulative water was 99.36%.

The responses of antioxidant systems after exposing Eisenia fetida to actual soil contaminated with PCBs were investigated. Among antioxidant enzymes, the primary response to early PCBs exposure can be attributed to catalase (CAT) and peroxidase (POD). These two enzymes could have a combined effect on fighting damage by reactive oxygen species. An obvious increase in the activity of CAT was recorded at 4 mg kg-1 compared to the control throughout the whole test days. PCBs exposure caused changes in POD activity in 2d and 4d. However, the activity of POD in E. fetida tissues changed little with PCBs concentrations in day 8 and 16d. Superoxide dismutase (SOD) changed little with PCBs in different time. The results suggest that the variations in CAT and POD of E. fetida could be used as early responsive biomarkers for oxidative stress caused by PCBs in a soil environment.

To investigate the concentrations of oxytetracycline (OTC), tetracycline (TTC), chlortetracycline (CTC) in pig feeds and manures, 30 samples of pig manures and 30 samples of pig feeds in different growth periods of pigs were sampled in Zhejiang Province in China. The results showed that the means of the concentrations of OTC, TTC and CTC in pig feeds were 8.76, 6.62 and 23.26 mg kg-1, respectively. The concentrations of OTC, TTC and CTC in manures were 2.98, 3.00 and 4.62 mg kg-1, respectively. The concentration of CTC in pig feeds were 2~4 times higher than that of OTC and TTC. The concentrations of OTC, TTC and CTC in manures from piglets were positively correlated to those in their feeds, with the correlation coefficients of 0.64, 0.61 and 0.58, respectively. It suggested that less amount of antibiotics should be added in piglet feeds than in other pig feeds.

Based on the theory of limit equilibrium, by the GEO-SLOPE software,analyzed the stability before and after reinforcement of a high Loess-bedrock slope. The results and conclusions show: (1)Analyzed and Optimized the high Loess-bedrock slope through SLOPE/W module, optimizing the engineering quantity of the anchor cable frame in the local and saving the investment; (2)When taken reinforcement measures, conducted the SLOPE/W model again, the stability coefficient is 1.459, the effect testified by projects is obvious; (3)Aiming at the optimization analysis, proposed countermeasures system, with reference for reinforcement of a high Loess-bedrock slope.

Considering each interdune lowland as a self-contained unit, we investigated species composition of 15 interdune lowlands in stabilized and active dunes, respectively, and identified the relationship of species richness and lowland area. The results showed that 1) with the enlargement of lowland area, the overall species richness of interdune lowlands in stabilized and active dunes increased logarithmically. When the area was the same, richness of stabilized dunes was more than that of active dunes. 2) with the increasing of lowland area in stabilized and active dunes, psammophytes richness relative to the overall species richness decreased logarithmically. When the area was the same, the percentage in lowlands of active dunes was more than that of stabilized dunes. Therefore, We concluded that dune stabilization, on one hand, raises species richness and on the other, leads to the loss of endemic or rare psammophytes in interdune lowlands.

Based on the FE software ANSYS, the coupling temperature fields of pin-disc friction pair were simulated and analyzed in pin-disc friction rig. The results show that the temperatures of pin-disc friction pair with magnetic field are higher than that without magnetic field, under the same relative displacement, speed and normal pressure. The maximum coupling temperature increase slowly and then increase quickly with the increasing of normal pressure, under the constant magnetic field intensity and speed. The maximum coupling temperature decreases with the increase of relative speed, when the relative sliding distance and magnetic field intensity are constant.

The corrosion resistance of slag α-Sialon ceramics, preparedviapressure-less sintering and hot-pressing from slag α-Sialon powder, to NaOH and HNO3was studied in this work. The result shows that slag α-Sialon ceramics have exellent corrosion resistance to NaOH and good resistance to HNO3. The corrosion mechanism and corrosion mode of acid and alkali to slag α-Sialon ceramics was investigated by means of scanning electron microscopy (SEM), and the results indicate that the corrosion of acid and alkali to hot-pressing ceramic is the slow surface corrosion, not only on the crystal grains, but also on the grain boundary phase, while the fast pitting is the dominant corrosion mode for pressure-less ceramic. The corrosion of NaOH solution to ceramics mainly occurred the grain boundary phase, while not only the grain boundary phase, but also crystal phase are corroded by HNO3.

Based on the understanding of diseases of building’s foundation and manmade slope caused by water capillary rise, this thesis carried out a large number of laboratory tests by selfdeveloped absorption permeameter for unsaturated soil, in order to explore the capillary transport law of unsaturated soil. The thesis obtains some valuable results and conclusions: The moisture content shows minishing trend as the seepage fronts increasing, and reflects the gravitational potential of normal relations with the capillary action; (2) the water seepage frontal Hω% relation curve has no obvious inflection point, but the initial water content has an certain influence on the capillary moisture content distribution, the moisture content uses the initial moisture content of 12.5%, 9.8%, 8.0% and5.3% for testing showed an increasing trend at 4 cm and 16 cm sections, and the moisture content at the same section increased with the initial moisture content increasing, this reflects the rule that the smaller the moisture content is, the greater the matric potential, the water absorption capacity becomes stronger. (3)The moisture content difference between 4 cm and 16 cm of the initial moisture content is 12.5%, 9.8%, 8.0% and 9.8% is 1.48 %, 1.5 %, 1.7 % and 2.2 %, indicating that the smaller the initial moisture content is, the difference at the vertical section is greater. Finally, based on the relationship of Hω% curve, the thesis establishes the grey correlation prediction model, and forecasts the maximum capillary height of Lishi loess is 182cm.

Soil moisture and soil seed bank are primary dependent factors during the vegetation natural regenerations in semi-arid sand areas. But the binary correlation analysis between seedling density and soil seed bank density as well soil moisture in transition zones between the windword slope of active dune and interdune lowland indicated that the correlation between seedling density and soil seed bank density was not significant (P>0.05) in the plant growing season; but the one between seedling density and soil moisture was significant and positive (P

The pot experiments were carried out to test planting of oil sunflower with the application of desulfurization gypsum in ameliorating sodic salinity soils. Results showed that exchangeable sodium pH values decreased significantly while soil salt content increased. The germination rate and yield of the sunflower increased significantly after desulfurization gypsum was applied, but excessive application of desulfurization gypsum inhibited germination and growth of the plant. There is the best improvement after application of 33.75(t·hm-2) of desulfurization gypsum in the 0-20 cm surface layer of soils moderate in sodic salinity, such conditions are favorable for sunflower growth.

This paper analyzed the deformation and stress of the glass substrate and the supporting columns in the vacuum plate glass in high-temperature sealing process with Ansys, which can forecast and guidance for the vacuum flat glass of high-temperature sealing. By performance test of vacuum plate glass after sealing, conclude the organizational structure of glass and welding agent junction is well. The vacuum plate glass of high temperature sealing has a good sealing performance.

The dynamic balancing of crank-slider mechanism was achieved with the guidance of the computer aided simulation-based optimization technique. Taking the reaction force of the rotary pair of connecting links and the input torque as optimization objective functions, the design optimization process was carried out with random-direction optimization method after determining the sensitive independent variables and their variation ranges based on the synthetical planning. The modal damping parameter of simulation model was optimized with the guidance of dynamic balancing experiment and the accuracy of simulation was also improved. Finally, by comparing the results from experiment and from optimization simulation, it is shown that optimization simulation could facilitate to instruct and implement the synthetical dynamic balancing for four-bar mechanism.

We developed a supercritical CO2 extraction procession and determinated ginger essential oil contents from the ginger oleoresin to explore the effects of temperatures or pressures on the supercritical CO2 extraction. Our research indicated that pressures had little effect on the liquid CO2 extraction capacity. However, supercritical CO2 extraction capacity was affected dramatically by the variant pressures. Additionally, changing pressures or temperature pushed the CO2 into transcritical isolation state. Under this circumstance, we not only ensured the yield of ginger oleoresin, but also did we obtain the ginger essential oil and gingerol simultaneously.

We developed a new procession of extraction efficiency of ginger oleoresin by comparing the CO2 flux in liquid state with that in supercritical state under variant pressure conditions. In our this report, we found that the optimal parameters of this procession: 9～10MPa in extraction pressure, 10～20°C in extraction temperature, 8～10MPa in isolation pressure, and 35～45°C in isolation temperature. This procession is steady and ensures both the extraction yield of ginger oleoresin and the low cost of operation.

In order to improve reservoir fluid recognition, sensitivities of array induction response to different invasion properties in both oil-bearing layer and water layer are analyzed. A numerical algorithm is adopted to simulate time-lapse response of array induction logs during mud invasion and signal processing of the array induction log is developed. Features of array induction responses during mud invasion were researched. A “five-parameter model” (r1, r2, Rxo, R1/2, Rt) which can match a variety of invasion conditions is approached and carried out suing a fast invasion method. Therefore, the identification of fluid type can be realized effectively by inversion of array induction log combined with time-lapse responses of array induction log. It is demonstrated that the inverted resistivity presents a typical non-monotonic variation in oil-bearing layer and a monotonic variation in water layer, which agrees well with the actual invasion property. It provides quantitative information for the discrimination of oil/gas or water zone.

Blast can cause serious loss of people live and property，and heavy damage on building structures. So, a numerical study on internal-blast-field characteristics and dynamic response of concrete by aluminized explosive was conducted. Moreover, three energy release models of aluminized explosive with combustion effects were compared and analyzed. The numerical study shows that the ignition and growth model is one three-form equation of reaction rate, which can describe unsteady detonation process of non-ideal explosives well. So, in this paper, the energy release model of aluminized explosive based on the Lee-Tarver rate equation was utilized, and an internal-blast dynamic model of concrete was established. The smoothed particle hydrodynamics (SPH) method was adopted to research the explosion field and damage effects of concrete, and provides an important way to evaluate the damage effect of internal-blast of the concrete.

Myofibrillar protein gel properties were studied. Based on which Box-Benhnken center-united experiment was designed for optimization of ratio scheme for gelation strength. The optimum conditions for best gel strength were found to the transgluninase 0.37% of myofibrillar proteins, GDL 1.19%, in 0.88mol/L NaCl concentration at pH 5.96 to form 40mg/ml protein concentration solution. The gel strength was 316.953g. The study showed that transgluninase and GDL could interact significantly in improving gel strength (P

An efficient method is described for the synthesis of 2-methoxy-thieno[2,3-d]pyrimidin- 4(3H)-one (5) via Gewald reaction, a tandem aza-Wittig reaction and cyclization process. The key step is an aza-Wittig reaction between iminophosphorane (2), 4-chlorophenyl isocyanine and nucleophilic reagent CH3OH. Its structures were determined by means of MS, IR and 1H NMR spectra.

Flexible forming using plasma arc (FFUPA) is a newly developed process of sheet metal forming, which can deform the sheet metal without mould and die, and thus is a promising method for rapid prototyping and short-run production. To achieve a large bending angle, it is unavoidable to scan the sheet metal for multiple times. However, the average bending angle reported in literature for each time is limited. To obtain a larger bending angle by each scan, this paper proposes a new scanning process, in which an assistant heat source is placed ahead of the plasma arc. The proposed scanning process has been studied by numerical simulation and optimized for the optimal processing parameters.

In view of the complexity, redundancy and uncertainty of measuring data generated by mine environment monitoring systems, a structure of two level data fusion, an adaptive weighted first level fusion and a second level fusion of grey correlation analysis, is presented, thus to achieve the fusion for the monitoring data from heterogeneous data sources and the fusion for the data from heterogeneous sources. Application examples shows that the fusion model has stable performance with strong anti- interference and can be handled easily.

t is pre-mordant dyeing. Dyeing property of Carmine, gardenia yellow and sodium copper chlorophyll on cotton fabrics which were pre-treated by metal mordant (FeSO4AlCl3 and ZnCl2 ) was studied. The reasonable pre-treatment was determined by comparing the color depth (K/S value) of dyed samples. And then, the dyed samples were treated with no-iron finishing resin 931-33 to fix the color. The result shows that the color depth of cotton fabric is greatly improved after determined pre-treatment, and the washing fastness is improved after color fixing.

This paper presents an effect method to reveal the load transferring and sharing law of anti-sliding piles under different isosceles trapezoid sections. Three kinds of cross-section, including the rectangle and two typical kinds of isosceles trapezoid cross-section, were carried out the load transferring and sharing tests on the basis of soil arching analysis by using the numerical modelling method. The results show that the anti-sliding piles row play an important role in resisting the driving force of the landslide, and the outer-isosceles trapezoid cross-section piles can reduce the driving force of the sliding mass in front of the piles to the maximum extent. The monitoring positions where more close to the piles transfer larger driving force from the soil to the piles. Moreover, the mechanical mechanism the anti-sliding piles with outer-isosceles trapezoid cross-section is end-bearing pattern, while the anti-sliding piles with rectangle and outer-isosceles trapezoid cross-section are end-bearing mixed with friction pattern.

The effects of different pH values and temperatures on the dyeing behavior of three types of natural pigment (lac dyer red, gardenia yellow, gardenia blue) on wool fabric was determined. The optimal dyeing temperature was found to be 100degC and the optimal pH value was 4 when using the most suitable mordant, aluminium sulfate. After mordant dyeing the fabric colour fastness basically met the requirements.

AlN and TiN thin films are widely used in electronic devices and acoustic material and other fields because of its unique merit, the preparation of nitride thin films by using the arc ion plating has not been a systematic and deep study. The article presents our research procedure which the AlN and TiN thin films are deposited on stainless steel substrate by arc ion plating (AIP). The characteristics of thin films, for example microstructure, morphology, composition analysis and hardness, are examined and analyzed. The results showed that: Droplet-like particles appear in the microstructure of nitride thin films, and the grain size of droplet-like particles in AlN thin films is greater than in TiN thin films. The micro-hardness of nitride films preparation in experiment has improved significantly, and establish firmly basic for extending the application field of nitride film.

This paper establishes a 3-D localization model and based on this model, it proposes a collaborative localization framework. In this framework, node that observes the object sends its attitude information and the relative position of the object's projection in its camera to the cluster head. The cluster head adopts an algorithm proposed in this paper to select some nodes to participate localization. The localization algorithm is based on least square method. Because the localization framework is based on a 3-D model, the size of the object or other prerequisites is not necessary. At the end of this paper, a simulation is taken on the numbers of nodes selected to locate and the localization accuracy. The result implies that selecting 3~4 nodes is proper. The theoretical analysis and the simulation result also imply that a const computation time cost is paid in this framework with a high localization accuracy (in our simulation environment, a 0.01 meter error).

In this dissertation, the electric arc spraying coatings on steel structure were sealed over with the organic coatings addition with nano-sized TiO2, SiO2. Some means as light microscope, SEM, energy spectrum and binding force tests were adopted for research the permeability of the sealer. The mechanism for permeable closeness of the sealer was mainly discussed. The results indicated that homogeneous nanofillers can improvement the runnability and permeability of the epikote, stiffen the adhesion between the coatings and the metal substrate. The coating can seal the metal substrate effectively; enhance the protective property of the tectonic systems with electric arc spraying coatings and organic coatings.

The Shoushan Stone is one of the famous craft carving stones in China and the transparency is one of the decisive factors to appraise its value. The better the transparency is, the higher the value is. In this paper, the mineral compositions and morphology of some Shoushan Stone samples were investigated by XRD and SEM methods. Combining with the characterization of Shoushan Stone, the relationships between the morphology and the transparency of Shoushan Stone were studied. The results show that the transparency of Shoushan Stone samples was determined by their microstructures, such as the mineral particle sizes and its arrangement, the gaps and porosity. The Shoushan Stone samples with high transparency are those with good arrangement, bigger crystal particle and less porosity and gaps.

Supercritical carbon dioxide extraction had been used in the extraction conditions for carotenoids from the marigold flower (Tagetes erecta L.). Five significant factors (particle size, temperature, pressure, time and co-solvent addition) on total carotenoid yield were obtained using one-at-a-time design (p≤0.05). The optimal extraction conditions were 55 oC, 50 MPa and 180 min. Under these conditions, the yield of carotenoids was 6.872mg/g.