Preparation and photocatalytic properties of Pt and Crco doped Nano TiO2 films 

Pt and Cr co doped Nano TiO2 film was prepared by the sol gel method. The film was characterized by AFM, XRD and UV Vis. The experiment showed that when the average TiO2 film diameter is 32 nm and the film thickness is 290 nm, the rate of photodegradation is 95% in 2.5 hours. Additionally, when the optimal co doping ratio for Pt Cr is n(Pt): n(TiO2) equals 0.03% and n(Cr):n(TiO2) equals 0.4%, the photodegradation of methylene blue for Nano TiO2 film can be enhanced. The photocatalytic properties of Pt and Cr co doped Nano TiO2 film is better than that of pure TiO2 and Pt, Cr separately doped TiO2 film.     

Analysis of the Double-layer Sub-grade with Rigid Upper Layer and Soft Lower Layer by FEM

The double layer subgrade with rigid upper layer and soft lower layer is common in engineering construction. In this paper, the elastic and elasto-plastic analysis on such subgrade by ANSYS was carried out. According to the calculation results of FEM, the plastic zone of subgrade would appear in the upper layer soil of interface, then, it would be expanded up and down with increase of the load. As for the lower layer soil is relatively soft, the plastic zone is expanding rapidly. Finally, as the plastic zone reaches the bottom and the subgrade in the state of ultimate bearing capacity, the calculation starts to be non-convergent. The results can serve as reference to the engineering designers.     

Identification of Pinellia ternata by high performance liquid chromatographic fingerprinting

The chromatographic fingerprint of Pinellia ternata was established by high performance liquid chromatography (HPLC) using an Agilent C18 (5 μm, 4.6×250 mm) column; CH3OH∶H2O as elution solvents; an ultraviolet detector at 254 nm; a flow rate of 1.0 mL/min. The guanosine peak was used as the reference and the relative retention value α and the relative area Sr as the parameters for the survey of the chromatographic fingerprint. Nine co possessing peaks were selected as the charaterizing fingerprint peaks to distinguish Pinellia ternata from false Pinellia ternata. The relative retention time of the 9 peaks were 1.00, 1.12, 1.50, 1.56, 1.60, 1.67, 1.71, 1.81 and 1.87, respectively. These peaks can be used to identify the quality of Pinellia ternata.     

Numerical simulation of NO and N2O emission in fluidized bed reactor

Both NO and N2O emission in fluidized bed reactor are studied by numerical simulation. The effects of excess air ratio, coal composition and co combustion of coal and biomass are researched. The results show that NO and N2O are the main products of the NOx in the fluidized bed reactor combustion, and the emission of NO and N2O increases with the excess air ratio increasing. The NOx production has strong relationship with coal composition. The nitrogen content of the coal plays an important role in the production of NO and N2O, as well as oxygen to nitrogen mass ratio and hydrogen to nitrogen mass ratio. In the co combustion process of coal and biomass, carboxyl group have remarkable effect on HCN production, which reduces the content of NO and NO2. The co combustion of coal and biomass can reduce the emission of NO and N2O.     

THE MANUFACTURE OF SELFGROWING A1_2O_3 -Al COMPOSITE AND ITS FORMING MECHANISM

The A12O3 layer on moten aluminium alloys can be damaged in some technological conditions. By capillarity the molten metal will rise to the surface through the broken place on the loyer and form a new A12O3 layer which is not compact and can be passed by molten metal too. This is a self-organic process by which a self growing A12O3-A1 composite with some thickness will be formed on the surface of the molten metal. The proportion of A12O3 in the material can be controlled from 20%-80% while the qualities especially the hardness and tensile strength, are all higher than thoses of the powder metallurgy materials.     

Natural Ventilation Design in Architecture

The natural ventilation is a technical means adopted widely in energy conservation building. According to the theory of natural ventilation, it can be divided into some forms including the natural ventilation by wind pressure, by different pressure in temperature, by combination of both and mechanically supplementary ventilation. In this paper, the theory of natural ventilation is analyzed with examples, then, the theory of double layer enclosure and the natural ventilation in high-rise building are discussed.     

Using BP Neural Network to Determine the Membership Function of the Input of Fuzzy Control System

While design the fuzzy controller, it is very important to determine the membership function of fuzzy variables.The data can be broadly classified as fuzzy sets by using the classification property of the BP neural network. The author selects a BP neural network with one hide layer and uses S function to the input and hide layer, and linear function to the output layer.Advanced BP algorithm isused to train the BP neural network in the environment of MATLAB . The nearer to the target values is the better the last output is.With the trained BP network , the membership values of the inputs can be got ten. This method has high rate and low error.     

Removal of Oxytetracycline in Water by Improved UV Disinfection Process

The removal of oxytetracycline (OTC) in water by UV, UV/TiO2, UV/Zeolite, and UV/Composite photocatalyst with different ratio was investigated respectively with a 32W low voltage mercury lamp. The effects of composite photocatalyst concentration, initial OTC concentration and pH value on degradation were also investigated. It was shown that the UV/Composite photocatalyst with 10% TiO2 and 90% Zeolite was an effective one to remove OTC in water. And in a solution with 50 mg/L OTC in ultrapure water the OTC was removed by 99% within 120 min with the help of 300 mg/L composite photocatalyst. The degradation of OTC by UV/Composite photocatalyst was little influenced by its initial concentration, but influenced by its initial pH. In the environment with pH+2~10, the OTC was removed by more than 95% within 120 min with the help of UV/Composite photocatalyst, when the pH is above 10, the removal rate is rapidly decreased.      

Effect mechanism of ions on sonolytic degradation of two organophosphorus pesticide

The effect of ions on sonolytic degradation of two typical organophosphorus pesticides (parathion and dimethoate) is investigated. In experimental condition ranges, both the parathion and dimethoate degradation conform to pseudo first order kinetic model. With the increasing of ionic strength, the degradation rate of parathion and dimethoate increases at first then decreases. When the ionic strength is 0.01 mol, the degradation rate of parathion and dimethoate increase by 7.2% and 18.6% respectively. The effect of ionic strength on dimethoate degradation is more significant compared to parathion. The reducible cations Fe2+ and Mn2+ at level of 0.1 mM have an obvious catalytic effect on both parathion and dimethoate degradation, and the catalytic effect of Fe2+ is more obvious than Mn2+. The catalytic effect of Fe2+ and Mn2+ increases firstly but then decreases with the increase of the cations levels. The CO-3 , HCO-3, and Cl- at the level of 0.01M exhibit inhibitory effect on both parathion and dimethoate degradation, and their inhibition degrees follow the order of CO-3>HCO-3> Cl-. But only 1mM of Br- has an obvious catalytic effect both on parathion and dimethoate degradation, and the effect increases with the increasing Br- level.     

Design and FPGA Implementation of animproved structure of digital matched filter

An improved structure of digital matched filter(DMF)is presented. Two same pseudorandom spread spectrum sequences with the length of N are used to spread the same baseband symbol at the transmitter, which is equal to spread the baseband symbol with a spread spectrum sequence with the length of 2N. At the receiver, only a spread spectrum sequence with the length of N is needed to de spread the data, and then cumulates the two correlation peaks and exports to the output. The detection probability(Pd)and the false alarm probability(Pf)are analyzed and simulated. The improved structure of DMF is implemented based on the recursive and folded principle. Experimental results show that, for the same spread gain, the improved structure has the same Pd and Pf as the basic DMF, while saves the hardware resources greatly compared with the recursive and folded structure.     

Behaviour of Reduction and Impoverishment of TiO2 in Molten Slag in Smelting Silico-titanium Ferroalloy Using Titanium-bearing slags by Electrosilicothermic Method

In this paper the mathematical model is established on the behaviour ofreduction and impoverishment of TiO2 in molten slag in smelting silico-titanium ferroalloy usingtitanium bearing slag by electrosilicotherinic procese under experimental conditions.It is studied thatthe influences of smelting conditions,such as smelting temperature,initial basicity of burden,quantity of reductant,smelting time and TiO2 content of slag on the reduction and impoverishmentof TiO2 in molten slag.     

Fabrication and thermal expansion properties of particle reinforced Al matrix composites

Aimed at electronic packaging application, the different types of particles of Al2O3, AlN and SiC which the mean size is about 4 μm are selected and three types of composites are fabricated by squeeze casting method with the particle volume fraction is 40%. The results show that the microstructure of composites is dense and free of pores with the particle distribute uniformly. The mean linear coefficient of thermal expansion (CTE) of composites ranges from 11.51×10-6~18.62×10-6/K and increases with increasing temperature. The measured coefficient of thermal expansion of SiCp/2024 is lower than that of AlNp/6061 and Al2O3p/2024. The measured CTE values of Al2O3p/2024 composites agreed well with Kerner’s model, the CTE of AlNp/6061 is closer to the prediction by ROM, and the CTE of SiCp/2024 varies from lower limit to upper limit of Shapery’s model.     

The Passive Dehumidifying Solar House

This paper presents a passive dehumidifying solar houase(PDSH),with combination of the Trombe wall and the dehumidifying air layer.For the envelopment of PDSH a porous slab with salt soluiton is inserted into the air layer of Trombe wall.This slab can absorb moisture at inner side and release moisture at outer side.The PDSH wall can dehumidify the room during the outer air layer open in summer and have heatstoring during the outer air layer shut in winter.It is an important character for the Trombe wall.So,the PDSH wall can be applied to insulation and heatstore,or dehumidifying and cooling.Therefore,the PDSH wall can be adopted everywhere in the world.     

A Study Transient on Predictive Calculation Method of on Underground Ventilation Network

The authors developed a computer program of transient predictive calculation method on underground ventilation network. The program approximated a field data set of seasonal cyclic changes of air Temperature and humidity at the inlet to the sine curves, and included sensible heat conduction from rock to air current. The temperature of rock around and airway was calculated by finite difference method. The prediction method can be used to calculate the variation of flow rates, temperatures and humidities of air flow in the airways along underground network.     

Preparation of TiFe alloy by electro-deoxidization in molten calcium chloride from titanium concentrates

TiFe alloy is prepared by the electrolytic reduction of molten-solidified titanium concentrate in molten CaCl2, which is obtained under argon atmosphere. The formation mechanism of TiFe alloy is discussed. The impact of electrolyte time on product is studied when electrolyte voltage is 3.1 V and electrolyte temperature is 900 ℃. Research results show that TiFe alloy with uniform composition can be obtained by this means. The deoxidize product is iron and TiFe alloy by order. The reduction of Ti is a multi-step process and the intermediate products include CaTiO3, TiO2, Ti2O3, TiO, Fe and TiFe2.     

Effects of nitrite on the growth and competition of Microcystis aeruginosa and Scendesmus quadricauda

Not only population densities of phytoplankton but also its community structure can be influenced by nitrite concentration.To investigate this effect,the growth and competition of Microcystis aeruginosa and Scendesmus quadricauda under different nitrite concentrations are studied by using batch cultures,and the competition relation is analyzed by the competition parameters.The results indicate that there is competition between M.aeruginosa and S.quadricauda in present experiment conditions,and S.quadricauda is dominant in competition.Meanwhile,the increase of nitrite concentration can strengthen S.quadricauda dominance,because under high nitrite concentration (20 mg/L,30 mg/L),M.aeruginosa is more damaged and the allelopathy between M.aeruginosa and S.quadricauda is intenser.     

Study on NO2 gas sensing characteristics of In doped ZnO thin films prepared by RF magnetron sputtering

In doped ZnO thin films were prepared on glass substrate by RF magnetron sputtering. The result of XRD and AFM shows that the films are polycrystalline with high c axis orientation. The study of gas sensing reveals that the films are sensitive to NO2 and the best sensibility occurs at 273 ℃; the sensibility is concerned with the concentration of NO2 and the film thickness. The ZnO∶In films are more sensitive to the NO2 gas with higher concentration of NO2 and thinner films have a better sensitivity. Exposed to 2×10-5 NO2 at 273 ℃, the 90nm thick film has a sensibility of 16, indicating that ZnO∶In films can be used to measure NO2 with a low concentration.     

Parameters Restricting the Coefficient of Performance of Centrifugal Refrigerating Units

We used the variance analysis method to analyze the effects of the proportion of the actual operated load, the pulse on degree of guide baffles, the temperature of cold water of the outlet, and outdoor relative humidity on the coefficient of performance (COP) of centrifugal refrigerating units. When the confidence level is set as 95% and 99%, respectively, the results of single factor variance analysis of the above four parameters show that the test statisticF of the pulse on degree of guide baffles is higher than its critical value F0.01 (r-1,n-r), which establishes that its influence on the COP is quite remarkable. The test statistic F of the proportion of the actual operated load and the outlet temperature of cold water are higher than their own critical value F0.05 (r-1,n-r), which shows that their influence on the COP is remarkable. The test statistic F of outdoor relative humidity is lower than its critical value F0.05 (r-1,n-r), which demonstrates that its influence on the COP is unremarkable. The results of the two factor variance analysis of the cold water outlet temperature and outdoor relative humidity show that the test statistic F of their interaction is higher than its critical value F0.01 (r-1,n-r), which indicates that influence of their interaction on the COP is very remarkable. The actual COP value of centrifugal refrigerating units can increase by 6.885% in average on the condition of the invariable refrigerating capacity after adjustment according to the analytical results.     

Exact Calculation for Measuring Electric Intensity with Ellipsoid Gauge

Based upon the anisotropy of electric polarization,the nonolinear oscillation equation of the ellipsoid in electric field is constructed by considering the rotative moment between electric field and the induced dipole moment on metallic ellipsoid of field intensity gauge. The oscillation period relative to the amplitude and electric intensity is calculated.An expression of exact computation to measure the electric field intensity is achieved.The impact of the amplitude parameter upon the experiment calculation is analyzed and the method to determine the amplitude is contributed.A contrast to the computed resuls by means of linear oscillation is undertaken to show the raising effect to the calculation precision by considering nonlinearity in oscillation.     

Using waste concrete as a replacement for natural limestone to produce cement clinker

Four samples of waste concrete with crushed limestone as coarse aggregate were collected from four different demolition sites. Each sample was crushed into particles which were then screened by sieves to remove smaller particles of given size. The residue was retained for use. Most of the residue was the crushed limestone; it was used to replace natural limestone as the calcareous raw material to produce cement clinker. These four clinker samples were compared with the similar Chongqing Lafarge cement clinker and some selected Portland cements on the market. The comparison results of XRD indicated that the XRD characteristic apex of the four principal compounds in the usual cement clinkers, C3S, C2S, C3A and C4AF, are strong enough in the clinkers produced by the waste concretes. All the free CaO content in the clinkers produced by the waste concretes was less than 1%, meeting the requirement of a given Chinese standard. It can be used to prepare Portland cements with strength grade of 52.5. The experimental results offer theoretical and technological guidance for efficiently reusing waste concretes.