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High alumina foam ceramics products with low density, high specific surface area, low thermal conductivity, corrosion resistance and other excellent physical and chemical properties are suitable for chemical, metallurgy and other related fields [1-4]. Alumina foam ceramics that compression strength increased by 200%, was prepared by Rizwan Ahmad through impregnation process using foamed rubber [5]. However foamed rubber was expensive and could be decomposed creating poisonous gases at high temperature. Zhou l z [6] prepared mullite porous ceramics with high strength by gel-casting method. Gel-casting is an effective method for preparation of ceramics products with large size and complicated shape. Fiber reinforced dense ceramics composite materials with excellent performance have been studied widely [7-10], it is also an important issue to adequately investigate the reinforcement of porous ceramics with fiber.

Engine intake system is one of the important parts of the engine which affects the engine’s volume efficiency and the uniformity of air entering to each cylinder directly Wherein the intake manifold with variable length is the important part of the intake system , has great significance value to research. Due to the structure of the manifold is complex, considering the manifold structure which affects the simulation accuracy, the principle of reverse engineering was used in this paper. Firstly, the laser scanning technology was used to obtain the point cloud data of the intake manifold.And then the cloud data was dealed by software Geomagic Studio12、NX Imageware13.The software UG8.0 was used to reconstructure the 3d intake manifold with variable length model.

The performance of the engine air intake system directly affect the working performance and fuel consumption, where the intake manifold design is the key.In this paper aimed at L91 Engine intake manifold ,firstly theRE(Reverse Engineering)technology was usedto rebuild the3d model of intake manifold.And then the internal flow zoneof the intake manifoldwas meshedin the pre-processing software ICEMand the internal flow fieldwas analyzedin the softwareof Fluent.The numerical model was verified by comparing the simulated and measured results. And then based on the numerical analysis of the internal flow characteristics of the intake manifold, the structure of variable-length intake manifold was come up with and finally was numerically proved to be better than the normal one.

Garlic puree turns green easily during the storage. And temperature is one of the greatest affects on degree of greening of garlic puree. The greening of garlic purees was evaluated by sensory analysis. It showed that 35°C was the best temperature to prevent garlic from greening. At the same storage time, different kinds of garlics were at different degree of greening. Organic garlic didn’t show absolutely advantage at preventing garlic from greening.

Polyether-modified polysiloxane was synthesized by hydrosilylation, using allylic alcohol polyether and polysiloxane as materials, toluene as solvent and chloroplatinic as catalyst. The effect of technology conditions on conversion rate of hydrogenous silicone oil was discussed and chemical structure of product was characterized. The results show that the optimum technology is: the reaction temperature is 95°C, time is 5h, the molar ratio of polysiloxane to polyether is 1:1.2, the dosage of catalyst is 30ug/g and the mass fraction of the toluene is 25% of the system.

The farmland soils around three typical livestock farms in Jilin province were studied to elucidate the impact of farms on heavy metal pollution in surrounding farmland soils. The results showed that the average content of Cd was maximal in the soils around cattle farm (0.29 mg kg-1); the average value of Pb was highest in the soils around the pig farm; and Cu, Zn, Ni and Cr were all highest in the soils around the chicken farm. The distribution of heavy metals in the soils around different livestock farms varied greatly. The contents of Cu, Zn, Ni and Cr decreased in the same order: chicken farm> pig farm > cattle farm, but Pb was pig farm> chicken farm> cattle farm, and Cd was cattle farm> pig farm> chicken farm. These results indicated that the livestock farms did not cause significant heavy metal pollution in its surrounding agricultural soils, but the accumulation of heavy metals caused by farms should arouse the attention.

The fire retardants were used in epoxy resin (EP) to get fire retardant EP, whose kinetic parameters activation energies (Ea) were calculated by Ozawa integral method and the Kissinger differential method. The results show that the correlation coefficient (R) is above 0.95, which shows good reliability of the two methods for solving Ea. E for the fire retardant foam is decreased by 40 kJ·mol-1, which shows that the fire retardant can catalyze decomposition and carbonization of EP.

Wood has been treated with amino resins and amino resins modified with phosphoric acid to impart flame retardancy. The thermal degradation of samples has been studied by thermogravimetry (TG) in air. From the resulting data, kinetic parameters for different stages of thermal degradation are obtained following the method of Broido. For the decomposition of wood and flame retardant wood, the activation energy is found to decrease from 122 to 72 kJmol-1.

This study employs a rapid, energy frugal and environmental friendly method to synthesize nitrogen doped titanate nanotubes (NTNTs), and uses TEM, XRD, Raman, Nitrogen adsorption-desorption isotherms analysis, and UV-vis spectroscopy to characterize the obtained NTNTs. TEM results indicate that NTNTs retain a tubular structure with a crystalline multiwall and have a length of several hundred nanometers after nitrogen doping. XRD findings demonstrate that the crystalline structure of NTNTs was dominated by anatase, which is favored for photocatalytic application. The Ti-O-N linkage observed in the XPS N1s spectrum is mainly responsible for narrowing the band gap and eventually enhancing the visible light photoactivity. After sintering at 350 °C, the UVvis absorbance edges of NTNTs significantly shift to the visible-light region, which indicates N atom doping into the nanotubes. Photocatalytic tests conclude that the NTNTs shows good efficiency with visible light response.

With expansion of enrollment scale, many universities make a large-scale expansion of their campus in recent years, which has caused a series of ecological problems, such as excessive occupation of land, destruction of local ecological environment. It is necessary to provide ecological level assessment and guidance for this eco-campus construction. Based upon the present related research at home and abroad and according to the basic principles of ecology, we have given a clear definition of ecological campus after considering the functional requirements for university campus at first, and then build an ecological campus evaluation index system in which the landscape ecology and the ecological footprint theory have been combined and clear the scoring method of each index. The index system includes five aspects: campus environmental quality, pollutant emissions, resource allocation and utilization, humanity landscape and greening, environmental awareness and environmental education. Furthermore, the analytic hierarchy process (AHP) is applied to this system to obtain the relative combined weights of every index which has passed the combined verify of coherence. Then the multi-factor comprehensive evaluation method was adopted to calculate ecological level index of eco-campus. At the end of this paper the main campus of Jinan University has been taken as an example application analysis of the index system.

The paper analyzed the necessity of PPP governmental supervision game on the basis of existed infrastructure government supervision and analyzed the policy, market and public benefit risk of private sectors, whereupon determined the setup of framework for PPP program government supervision. Supervision will mainly cover the following items: market access; service quality; service price; external supervision; social fairness etc. Lastly, the paper established ethnic risk model of private sector, and came to the following conclusion: degree of ethnic risk is positive correlated with the additional revenue from evil conduct y and market interest rate r, and is negative correlated with the reward from franchised business W, possibility of discovering evil conduct Po, fines derived from punishment of evil conduct D, term of franchised operation t, period of default i and reward declining amount x.

The highly ordered mesoporous MCM-41 was synthesized and modified with various content of aluminum (0-15%) using an incipient wetness impregnation technique. The prepared Al modified MCM-41 materials were characterized by XRD, and explored as adsorbents for arsenic(V) removal. Al loading and calcination temperature played significant roles in the absorbents structures and adsorption capacities. The maximal arsenic(V) adsorption capacity of 16.3 mgAs/gAl was obtained when Al loading of 10 wt% and calcination temperature of 400 °C were used.

The surface tension, CMC, HLB, emulsifying ability and hydrolytic stability of the polyether-modified trisiloxane surfactants were tested. The hydrolytic stability of different products was compared.

In this paper, based on the ultrasonic dispersion principle, the grafting reaction of maleic anhydride (MAH) onto solid PP in water was studied with acetone as the phase physiognomy solvent, ammonium persulfate [(NH4)2S2O8] as the initiator. The influence of specific surface area on the graft ratio was also studied. The results showed that the grafting reaction had obvious relationship with the specific surface area of original PP particles.

In order to solve the problem that the traditional cooling system cannot adjust the cooling water temperature to the different operation conditions of diesel engine, the auto-control cooling system is designed. Using it, the coolant temperature can be adjusted automatically by the single-chip which controls the transducer-controlled pump and the electronic dividing valve which replaces the thermostat. We use the thermal equilibrium bench to verify the figures, and the result is show that using the exhaust of generator heats the cooling water can shorten 13 minutes in starting process and the cooling water temperature adjusted automatically to the changing operation conditions of iesel can decrease the fuel consumption remarkably, the highest fuel saving rate reached 5.4%, the averagely fuel saving rate reached 3.6%.

In order to prepare special alcohol-soluble polyvinyl butyral (PVB), the reaction condition was explored in this paper after analyzing the molecular structure of PVB. Under a simple and economical condition, PVB with 14.2% of butyraldehyde group and good alcohol-solubility were prepared, the PVB film forms quickly after the volatilization of ethyl alcohol, and it has good diaphaneity, high tensile strength, and excellent mechanical properties. The highest tensile strength of the PVB film reaches 50.9MPa, which can meet some requirements of many applications.

This research presented the kinetic performance of arsenic absorption by mesostructure SBA-15 functionalized with Al2O3. The SBA-15 was previously synthesised and subsequently functionalized via impregnation of alumina oxides. The absorption of arsenic(V) was studied as a function of absorbent dosage and contact time. The experimental data were fitted to kinetic pseudo-first order, pseudo-second order and the intra-particle diffusion model. The pseudo-second order model presented the best correlation with the experimental data. Both surface absorption and intra-particle diffusion were acting during arsenic uptake, except for absorbent dosage of 0.1g, which was mainly controlled by the intra-particle diffusion.

We demonstrate a swept-source OCT system based on a polorization-dependent semiconductor optical amplifier (SOA)-enabled Fourier Domain Mode Locked laser (FDML). The broad bandwidth and high saturation power of the semiconductor optical amplifier enables single semiconductor optical amplifier operation with enough bandwidth and output power. The FDML generates ~32mW output power at 45kHz sweep rates, with a tuning range of 115 nm centered at 1326 nm. Using the SOA-enabled FDML laser, ~12.9μm axial resolution,9μm transverse spot size and 105dB sensitivity are achieved. OCT imaging of biological sample is also demonstrated.

The adsorbent was prepared from peanut shell by using Zncl2as activating agent, copper in aqueous solution was used as the adsorbate, the influence of pH, adsorbent dosage, temperature, contact time were investigated through dynamic tests. Then the kinetics of modified peanut shell was studied. The results showed that the modified peanut shell had maximum adsorption efficiencies when the pH was 6; the dosage was 0.2g; the temperature was 25°C and the contact time was 12h.By substituting experimental data into kinetics models, quasi-second-order kinetics model could better describe the kinetics of modified peanut shell adsorbing Cu2+.

The photovoltaic(PV) generation model and the wind power generation model are introduced in this paper. Taking the best economy and reliability of system operation as the objective functions and the system power balance and battery storage performance indices as the constraints, the optimal capacity of battery energy storage can be determined with the Tabu search algorithm. With the example system, the simulation results show that the proposed models and the algorithm are correct.

Kernel is a key component of the support vector machines (SVMs) and other kernel methods. Based on the data distributions of classes in the feature space, this paper proposed a model selection criterion to evaluate the goodness of a kernel in multiclass classification scenario. This criterion is computationally efficient and is differentiable with respect to the kernel parameters. Compared with the k-fold cross validation technique which is often regarded as a benchmark, this criterion is found to yield about the same performance with much less computational overhead.

This paper reports the adsorption of Cr(VI) ions from aqueous solution by organic-inorganic hybrid mesoporous material. Adsorbents were prepared with the DTAB,TTAB,CTAB and STAB for organic component synthesis organic-inorganic hybrid mesoporous material(HM), namely HMD, HMT, HMC and HMS. The best adsorption hexavalent chromium experimental conditions is obtained after having orthogonal experiment.

This paper studies the speech enhancement technology. A Lyapunov function of the tracking error systems is defined, and the adaptive filter based on FXLMS algorithm can make the error converge to zero asymptotically. It is shown to be suitable to solve the problem of the speech enhancement from computer simulations

This paper addresses the stabilization problem for a class of switched nonlinear systems with Lipschitz nonlinearities using the multiple Lyapunov functions (MLFs) approach. A state feedback controller and a state dependent switching law are proposed to asymptotic stabilization the switched system via linear matrix inequalities (LMI). The developed control strategy ensures asymptotic stability of the closed-loop system even if the nonlinear part . Finally, the feasibility of the proposed method is illustrated through a simulation example

In this paper the hydroxyapatite fibers reinforced chitosan nanocomposites with high hydroxyapatite dosage (70~90 wt%) were synthesized by in-situ hybridization. The semi-permeable membrane was used to control the process of hybridization and morphology of hydroxyapatite. The compositional and morphological properties of nanocomposites were investigated by FTIR spectroscopy, X-ray diffraction, and transmission electron microscopy. The results showed that the hydroxyapatite were carbonated nanometer crystalline fibers with high aspect ratio (about 25) and dispersed uniformly in the nanocomposites. The high-resolution image indicated that the growth of nano-hydroxyapatite crystallites in the chitosan matrix preferred in the c-axis. The mechanical properties of these nanocomposites were enhanced dramatically and the compressive strength increases almost to 170MPa when the hydroxyapatite content is 70 wt%. The in vitro tests indicated that the composites have high bioactivity and degradation. These properties illustrated the potential application of this kind of nanocomposites for bone tissue engineering.

This paper describes the procedure of a hybrid approach based on grey model and artificial neural network (GM&ANN) to analysis and forecast of deformation data. The GM&ANN is formulated into three steps:(1)according to the monotonously increasing characteristics and the nonlinear characteristics of deformation time series, total deformation can be divided into tendency part and stochastic part.(2) use GM(1,1)to fit the trend of the data and obtain the residual series, on this basis by using artificial neural network to fit the stochastic part (residual series) .Then the forecasting value of deformation is obtained by adding the calculated predictive displacement value of each sub-stack. (3) validate the model. The results of experiments show that this hybrid has higher performances not only on model fitting but also on forecasting and therefore can be applied to deformation data processing.

In order to provide the theoretical basis for synthetic fiber dyeing with natural dyes, the dyeing properties of chrysophanol on Poly(trimethylene terephthalate)(PTT) fiber were investigated. The appropriate dyeing condition was 0.5g•dm-3 Paregal O in the dyebath, pH=5 and the final temperature at 100°C~110°C. The dye uptake of chrysophanol on PTT fiber was relatively small, and the building-up property of chrysophanol on PTT fiber was poor. The adsorption of chrysophanol on PTT fiber accorded with Nerst Partition Relation. The partition coefficient decreased with the temperature rising while the dyeing affinity (-△μ0) increased with the temperature rising.

A natural peanut shell was used as adsorbent for removal of Cu(Ⅱ) from aqueous solution. Optimum conditions for the elimination of Cu(Ⅱ) from aqueous solution were established by means of a batch adsorption technique. The applicability of the Langmuir and Freundlich adsorption isotherms for the present system was tested. The Langmuir adsorption capacity Qmax (mg/g) is 39.68 and the equilibrium constant b is 0.00776. The Freundlich adsorption capacity k is 0.978 and adsorption intensity n is 1.65. The goodness of fitness was obtained with the Langmuir and Freundlich adsorption isotherms from the equilibrium adsorption data.

According to the feature of numeral image of electronic balance photographed by CCD, MATLAB, especially its video image toolbox, was used to achieve the manual character region location, automatical character segmentation and automatical digit recognition of the digit image in video signals. The method is able to recognize the values in the video signals with more than 97% correctness in multiple sampling tests. However, there were also some abnormal data caused by LED light retention in the dynamic display process and recorded by high frame rate video. The problem was solved by replacing the points outside the range with neighborhood median. This method is simple, highly adaptable and reliable, thus facilitate the research on filter media surface wettability and provide a set of reference for solution this kind of research.

Accurately estimating the deformation of high-rise buildings is a very important work for surveyors, however it is very difficult to get an accurate and reliable predictor. In this paper, a combined modeling and forecasting approach based on grey theory and the autoregressive model is proposed to forecast the deformation of the modern buildings. The results of experiments show that this method can forecast the deformation precisely, which provides a basis for performance analysis and forecasting. Meanwhile, it can also be concluded that the combined method has a higher forecasting precision to the complex problems than the single models, and therefore can be applied to deformation data analysis.

Two different kinds of structural preforms were designed and manufactured, which were 3D layer-to-layer angle-interlock structure and 3D solid orthogonal panel structure. C/C composites were made first by chemical vapor infiltration (CVI) and then liquid resin impregnation for complementation. The bending properties of the two 3D woven reinforced C/C composites were tested and analyzed. The inner microstructures were investigated by SEM. The results show that the bending property of 3D solid orthogonal panel preform reinforced C/C composites is higher than that of 3D layer-to-layer angle-interlock preform reinforced C/C composites, and the bending rupture of the former is brittle, the latter is tough.

In allusion to the significance of design stage to cost control in the engineering and based on analyze present problems in the design stage, it is a feasible way to put forward four efficient approaches in the design stage to control construction cost including quota design, design biding, value engineering and standardized.

This paper describes an numerical method and simulation experiment investigation on the rail wear affected by the curve radius and axle load etc. the effects of curve radius and axle load on The effects of axle load and curve radius on total slippage of contact particles and friction work of wheel/rail are investigated with numerical methods are analyzed by kalker’s program CONTACT. The effect of curve radius and axle load on rolling wear behaviour of rail is investigated by simulation experiment. It is indicated that axle load and curve radius are important factors to effect rolling contact wear of wheel-rail, and there is a linear relationship between wear volume of rail and friction work of wheel/rail; The preliminary empirical formula between wear volume of rail sample and friction work is given by analysis the experimental and calculation results, the formula offers a certain reference value for researching wear of wheel-rail and predicting wear volume of rail.

During drilling, how to achieve the aim of deviation control and fast drilling effectively is a common technique issue. Though there are some anti-deviation and well straightening methods at present in drilling fields, most of them have their disadvantages, such as decreasing the weight on bit (WOB) and the rate of penetration (ROP). These drilling methods can’t achieve the aim of deviation control and fast drilling economically and effectively in high dip, fractured, fault zones, and other abnormal formations. . Automatic Vertical Drilling System (AVDS) is a Mechanical-Electrical-Hydraulic integrated drilling tool, and it is also an intelligent drilling system. As an advanced technology, the AVDS is a great breakthrough in deviation control and fast drilling. According to the result of theoretical analysis and oilfield applications, the AVDS can not only increase the weight on bit and improve the rate of penetration greatly, but also can guarantee improved well bore quality. And perfect borehole quality is an important premise of subsequent operation while drilling. Φ311 Automatic Vertical Drilling System (Φ311 AVDS) belongs to the relative-static-effective AVDS, it has been experimented effectively and successfully in Xinjiang oilfield. By the results of the experiments, the indexes of the Φ311 AVDS have met the design requirements and achieved vertical and fast drilling aim in high dip formations. The paper aims to introduce the characteristics, operating principles and matching technologies of the Φ311 AVDS.

Distance fabric is a new structure textile characterized by its two parallel skins of 2D fabric integrally connected by large numbers of the through-thickness threads. The paper explores the principle of distance fabric forming and the weave structure developed by us, and introduces the weaving process in detail and also discusses some problems which should be emphasized in weaving this new structural textiles. The weaving practice indicates that the new theory of producing distance fabric is feasible.

The relationship between structures and properties of Kevlar string was studied scarcely before, although the string was used in aerospace, spaceflight, ocean and the like. Kevlar braiding strings were designed and braided with different braiding angle, different core yarn content and different twist, and stretching properties were measured and analysed in the paper. The result shows that the bigger braiding angle is and the more core yarn content is, the higher break load is and the lower break elongation is. Besides, rupture analysis proves that braiding Kevlar bundles take hold of core Kevlar bundles tightly, both form an inseparable integrity almost during stretching. As a result, a special phenomena occurs, core Kevlar bundles are broken into several segments.

Effects of various amounts of ground limestone on the setting time, fluidity and compressive strength of high alumina cement were described in this paper. Microstructure analyses were performed by SEM. The results indicate that the initial setting time, the final setting time, the fluidity and the compressive strength of the pastes increase first and decrease later with the ground limestone content increasing, all of which reach the maximum when the ground limestone content is 3%. Meanwhile, an increase of the fineness of the ground limestone produces a shorter setting time, the fluidity of the pastes increases when the content of the ground limestone increases, and the compressive strength of the hardened pastes increases with the ground limestone content increasing and decreases with water-binder ratio increasing. The 28d strength of the pure high alumina cement paste is lower than the 3d strength, appearing the strength shrinkage, which can be improved by a proper addition of the ground limestone.

The effect of wheel speed, axle load and track curve radius on wheel/rail adhesion properties under dry and water medium condition was investigated in this paper using JD-1 wheel/rail simulation facilities with Hertz simulation method, and then testing method of “four horizontals and three factors” was adopted to analyze the influence degree of speed, axle load and track curve radius on wheel/rail adhesion. Results from the experiment are that: The adhesion coefficient reached maximum at creep ratio of 1.5% under dry condition, and 1% under wet condition respectively; the adhesion coefficient under water medium condition occupy about a proportion of 32%-50% of that under dry condition. adhesion coefficient would reduce with speed increasing, axle load increasing and track curve radius decreasing under dry condition, and reduce with speed increasing, axle load decreasing and track curve radius decreasing under water medium condition; As far as influence degree of three testing factors which have effect on adhesion coefficient is concerned, axle load is the first one, then speed, finally track curve radius under dry condition, and speed is the first one, then axle load, finally track curve radius under water medium condition.

An investigation is reported in which four three-dimensional angle-interlock architectural fabrics were designed and woven. Composite panels were manufactured by impregnating the fabrics with resin.The related experiments included tension, compression and bending. All those tests were performed to measure the Young's moduli and strengths in the 0°(warp direction), 30°, 45°, 60°, 90° (weft direction). The experimental methods, preforms parameters were also described in this paper. The results show that, mechanical properties of four three-dimensional angle-interlock architectural composites behaved in-plane anisotropic , two peak values along the warp and weft direction respectively appeared in any one graph , and the yarn-stuffer played a key role in determining mechanical properties of three-dimensional angle-interlock architectural composites, especially contributed intensifier in corresponding direction obviously.

The rolling contact wear is a severe problem and meets with much widespread interest in the world. This paper describes an numerical method and simulation experiment investigation on the rail wear affected by the curve radius and axle load etc. The creep force ,stick/slip areas of contact particles, and friction work of wheel/rail in static condition are analyzed by kalker’s program CONTACT. The effect of curve radius and axle load on rolling wear behaviour of rail is investigated by simulation experiment. The results of numerical and experiment indicates that with the decreasing of curve radius and the increasing of axle load, the wear value of rail increase nonlinearly, especially in the condition of the curve radius is less than 1200m,the wear value of rail increase rapidly. And with the decrease of curve radius, the maximum slippage decrease gradually, and the stick areas decrease while the slip areas increase. The growth speed of friction work of wheel/rail in the condition of smaller curve radius and heavier axle load is faster than in the condition of larger curve radius (straigth line) and lighter axle load.

The fire retardants were used in flexible polyurethane foam (PUF) to get fire retardant PUF, whose kinetic parameters activation energies (E) were calculated by Ozawa integral method and the Kissinger differential method. The results show that the correlation coefficient (R) is above 0.95, which shows good reliability of the two methods for solving E. E for the fire retardant foam is decreased by 80 kJ•mol-1, which shows that the fire retardant can catalyze decomposition and carbonization of flexible PUF.

The rolling tests of railway rail were performed using a JD-1 wheel/rail simulation facility without any lubricant. The failure behaviour of rail rollers with different materials, was investigated in detail by examining wear volume and wear scar using optical microscopy (OM) and scanning electronic microscopy (SEM). The results indicate that rail material with a high hardness appears less plastic flow after rolling test. When the plastic flow is small, the wear resistance of material appears better. However, the crack propagation is more significant and fatigue damage is more severe. There is a mutual competitive relationship between wear and surface fatigue crack. A high wear rate can reduce rolling contact fatigue damage by removing constantly surface cracks. The analysis shows that U71Mn rail is more suitable for the high-speed railway.

In this paper, A kind of ideal non-cyanide silver deposits was obtained by joining the ultrasonic. ultrasonic frequency of 28KHz, power increased from 0-500W, XRD tests show:with the increasing in electric power deposition, silver coating (111) and (200) crystal plane orientation significantly improved, and (220) crystal plane orientation declined . With the ultrasonic power increased, silver deposition current efficiency increased first and then reduced. the grain size refined with the ultrasonic increasing .the corrosion resistance decreased with the ultrasonic increasing.and SEM showed that the grain sizes decreased with the ultrasonic.