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Thispaper presents an experimental study to strengthen an existing bridge usingpre-stressed carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer(GFRP) materials. The method using pre-stressed hybrid fiber reinforced polymer(HFRP) to strengthened structural members is an emerging pre-stressed strengtheningtechnology. In this study, experimental data selected from result of staticloading test conducted to hollow slabs with CFRP/GFRP has been compared with specimenswithout strengthening. Test results showed that the strengthening methoddeveloped in this study could effectively reduce the stress in hollow slab,improving the flexural rigidity and inhibiting the concrete from fracture.

The paper analyses the manufacturability and difficulties in weld repairs of the electroslag casting red copper crucible with bent axle, work out the relevant measure. It is proved by experiment that large red copper product can be perfectly repairs by use suitable welding procedure.

With the method of vacuum dc sputtering and vacuum evaporation,the green light double organic light-emitting devices (OLED) of ITO/CuPc/Alq3 / Al structure were prepared, the electrical characteristics and electroluminescent properties of the device were measured. Devices show good luminous performance, light intensity reaches 600000 cps, when the wavelength of luminescence spectrum is 510 nm, luminance is 2641I/a.u.

Panax ginseng (C.A.Meyer), belonging to Araliaceae family Panax category, has important commercial value and are used in worldwide. Ginsenosides, the major bioactive ingredients of P. ginseng, are classified into two groups by the skeleton of aglycones, namely dammarane-type and oleanane-type. Dammarane-type ginsenosides dominate over oleanane-type not only in amount but also in structural varieties. Here, we cloned and identified the Dammarenediol-II synthase gene named PNA encoding encoding enzymes catalyzed 2,3-oxidosqualene to dammarendediol-II by RT-PCT.we established PNA RNAi transgenic. The RT-PCT and HPLC analysis of the final products of protopanaxadiol-type and protopanaxatrio-type ginsenosides showed a result that declined level of protopanaxadiol-type and protoanaxatriol-type ginsenosides, and increased phytosterol content.

Ginsenosides, the major bioactive ingredients of P. ginseng can improve the anti-disease abilities of human being, and generate significant social and economic benefits. However, along with gradually or rapidly or dramatically increasing demand of the ginsenosides, extensive studies have focused on regulating the ginsenoside biosynthetic pathway on a genetic level. This review provides the latest research progress on biosynthetic pathway of ginsenosides, including the mevalonate (MVA) and the methylerythritol phosphate (MEP) pathway, which is newly discovered and located in P. ginseng. Moreover, it also indicated lanosterol synthase metabolic flux present in P. ginseng.

Ginsenosides, the major bioactive ingredients of P. ginseng can improve the anti-disease abilities of human being, and generate significant social and economic benefits. However, along with gradually or rapidly or dramatically increasing demand of the ginsenosides, extensive studies have focused on regulating the ginsenoside biosynthetic pathway on a genetic level. In this article, ginsenoside biosynthesis of key enzyme genes are described, including squalene synthase (SS), squalene epoxidase (SE), oxidosqualene cyclase (OSC), dammarenediol synthase (DS), β-amyrin synthase (β-AS), lanosterol synthase (LAS), cycloartenol synthase (CAS) and P450. Additionally, this review critically analyzes and evaluates the background and theoretical basis of the previous researches, as well as the deficiencies of these researches.

This paper will conduct a systematic study on method of recovering Ge from pulverized fuel ash in Lincang prefecture, Yunnan province. Details are like this, in view of the fact that Ge contained in pulverized fuel ash is wrapped up by a lot of Silica, Cao, magnesium oxide and is difficult to react with hydrochloric acid, so, first, have the pulverized fuel ash grinded to 200 meshes; then, ammonium fluoride should be put into 85-90°Cdilute sulphuric acid solution to produce hydrogen fluoride so as to destroy silicon dioxide and calcium oxide contained in the pulverized fuel ash. Meanwhile, dilute sulphuric acid solution dissolves magnesium oxide, by doing so, Ge will be released to react with sulfuric acid and produce Sulfuric acid Ge, and Ge will go into the solution；as for low state Ge（e.g,GeO,GeS）contained in the pulverized fuel ash which is difficult to be dissolved by sulfuric acid, sodium chlorate will be used as a kind of oxidant to change bivalence Ge into tetravalence Ge, then dissolve it into the solution, after the liquid-solid separation, sulfuric acid leaching solution rich in Ge will be obtained. Then, tannic acid will be used as precipitant to recover Ge from the leaching solution, and Ge concentrate will be produced through distillation and roasting. After this, put Ge concentrate on hydrochloric acid distillation to get germanium tetrachloride, After going through strenuous evaporation, distillation and hydrolysis, germanium dioxide with high purity will be yield. This paper has conducted conditional tests and discussion on the process parameters which will influence recovery Ge from pulverized fuel ash, including the dosage of Sulfuric acid, ammonium fluoride, sodium chlorate ,tannic acid and extraction time to find out the prior controlling condition of Ge recovery，under this prior condition, Ge leaching rate is as high as 84%，and tannic sinking Ge rate is as high as 98%. The pulverized fuel ash, after recovering Ge, can be used to backfill the mine pit, besides, most of the lixivium after recovering Ge can be recycled, and the rest of it will be released after neutralized up to the standard by lime. This process enjoys the following quality: high Ge recovery rate, less time used during the process ,less consumption of auxiliary material, easier to control the process, avoiding the potential pollution on the environment and lower cost involved in it, therefore, which is a kind of efficient and economic process of recovering Ge from pulverized fuel ash.

To Huanggang River watershed protection, for example, to carry out the exploration of environmental education on campus. River basin water pollution on the East China survey, indicating that the industry, and agriculture are the three sources of life; of the East China River Basin water quality trends and the causes of water pollution in Huanggang River Basin; described Huanggang the importance of water resource protection, and Defining the student's role in the protection of the environment.

We preliminary know FS powder and coal dust play in mix sand and analysis comparison influence of each powder through a series of mixture sand performance testing . We put forward on same addition, FS powder substitute coal dust is profitable to reduce defect of M593 Shell structure adhering sand.

In order to research the adhesion of sputtering protective coating of Gd. Gd substrates was coated with 1Cr18Ni9Ti by means of DC magnetron sputtering technology. The characteristics of the film were investigated by scanning electron microscopy (SEM), EDS, SPM and the adhesions of film was tested by tension test. The results show that the films of 1Cr18Ni9Ti are distributed by means of islands when the sputtering was initiated and the grains are like thin fiber. After a few minutes, the films are smooth and perfect, the interferences between 1Cr18Ni9Ti and Gd join together strongly, and the largest strength of adhesion is 24.7MPa when the sputtering density is 966 w/cm2 and the sputtering time is 8 minutes.

In order to research the adhesion of sputtering protective coating of Gd. Gd substrates were differently coated with 1Cr18Ni9Ti, Ti, Cu and Al by means of DC magnetron sputtering technology. The characteristics of the films were investigated by scanning electron microscopy (SEM), EDS, and the adhesions of films were tested by tension test. The results show that the films of 1Cr18Ni9Ti, Ti and Al are smooth and perfect, the interferences between 1Cr18Ni9Ti, Ti, Al and Gd join together strongly, and the average strength of adhesion is 25MPa in these tests on the optimize parameters. While the films of Cu are rough and bad, the interferences between Cu and Gd join together loosely, and the largest strength of adhesion is only 3.02MPa in these tests on the optimize parameters.

Al-4.5Cu-3Ce alloy semi-solid slurry has been prepared by using slope vibration casting. The effects of the pouring temperature, slope length, vibration amplitude and vibration voltage on alloy solidification microstructure were researched. Experiments show that these parameters play a significant role on the alloy microstructure. The uniform, small equiaxed microstructure of Al-4.5Cu-3Ce alloy can be acquired by water-cooled copper mold casting at 680°C with slope length of 20cm, vibration amplitude of 2cm and vibration voltage of 80v. Its average grain diameter is 28.1um with average roundness coefficient of 0.82.

In engineering technology, it is necessary to compare different designs in an optimization project. Therefore a big problem is how to obtain finite element analysis (FEA) data involving different parameters and how to acquire optimization parameters from the results of FEA to solve the optimization problem rapidly. The parametric mesh (Paramesh) method, automatically based on history of complicated special surfaces, is developed to obtain many results of FEA involving different parameters. This paper is presented to demonstrate the method of parametric finite element analysis (PFEA). The optimization method of process parameters optimization is based on combining PFEA/ ANN (artificial nerve net)/GA (genetic arithmetic) to find out optimization parameters. This allows one to rapidly obtain optimization parameters during a design by doing FEA only once. The research indicates that the parameters optimization method based on PFEA/ANN/GA in the product design can short the product development cycle, decrease material consumption and guarantee product quality, etc.

Warm forming of magnesium alloy sheet has attracted more and more attention in recent years. Mechanics tension test has been made in this paper in order to study the constitutive relationship of ME20M magnesium alloy sheet at different temperatures and strain rates. And a constitutive relationship which includes a softening factor has been put forward. Warm deep drawing experiment and numerical simulation on ME20M magnesium alloy sheet have been made in which the attention was focused on the forming temperature. The results showed that the limit deep drawing height of ME20M magnesium alloy sheet can be dramatically improved as the temperature goes up, especially when the temperature was over about 250°C. Simultaneity, it is feasible and effective to add a material model into numerical simulation software by user subroutine.

A new technique using slope vibration casting process during heating and isothermal holding period to prepare Al-7Si-2RE alloy has been studied. The small, near-spherical and non-dendritic microstructure with the semi-solid processing requirements has been obtained. Experiments show that the cooling method, pouring process and the convection of melt caused by slope vibration had significant effects on the formation of near-spherical primary gains. The water-cooled copper mold casting with slope vibration at the temperature near liquidus can obtain Al-7Si-2RE alloy with small homogeneous equiaxed grains, the average grain diameter is 48.3μm, and the average grain roundness is 1.92.

In order to research the adhesion of sputtering protective coating of Gd.Gd substrates were differently coated with Cu and Al by means of DC magnetron sputtering technology. The characteristics of the films were investigated by scanning electron microscopy (SEM), EDS, and the adhesions of films were tested by tension test. The results show that the films of Al are smooth and perfect, the interferences between Al and Gd join together strongly, and the largest strength of adhesion is 27.6MPa in these tests on the optimize parameters through orthogonal experimental design. While the films of Cu are rough and bad, the interferences between Cu and Gd join together loosely, and the largest strength of adhesion is only 3.02MPa in these tests on the optimize parameters through orthogonal experimental design.

This paper aims to study the effects of rare earth Cerium addition on mobility, solidification shrinkage, casting microstructure and hot tearing tendency of Al-4.5Cu alloy. Results show that by adding appropriate rare earth Cerium into the Al-4.5Cu alloy, the viscosity of liquid metals can be reduced, the mobility of alloy can be increased, and the shrinkage during the solidification of liquid metal can be reduced. Further more, as the tendency of alloy dendrite is inhibited and the microstructure of the casting alloy is improved, the alloy can be purified, its thermal conductivity can be enhanced, and the hot tearing tendency of it can be decreased remarkably. It proves that when rare earth Ceriumaddition in Al-4.5Cu alloy is 4w%, the mobility of Al-4.5Cu alloy will be the maximum, and its volume shrinkage will be the least. Meanwhile, the grains of alloy are refined and round. The alloy also shows the lowest hot tearing tendency.

The effects of adding rare earth Cerium on Al-4.5Cu alloy microstructure, solidification range and volume changes in the solidification process are researched. Experiments show that rare earth Cerium will bring remarkable effects on the alloy microstructure, solidification and solidification shrinkage interval. When the quantity of rare earth Cerium is about 4 wt%, the solid-liquid two phase of Al-4.5Cu alloy will range from 640°C to 600°C. The grains of the alloy are refined, round. The volume shrinkage is only 68.6% of that without adding rare earth Cerium.

There is strong interest in a robust lower power wireless solution for utility meter reading, especially for reading electricity meters. This paper describes a mesh network that is relatively simple to implement and takes up less resources than well known alternatives such as Zigbee.