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The long persistent phosphor SrS: Eu2+, Dy3+ was prepared by hydrothermal method. The crystalline structure was characterized by using X-ray diffraction (XRD). The experimental excitation spectrum was carried out with Flurolog-3 fluorescent spectrometer. The results show that there are seven sharp sub-peaks on the wide band spectrum. This paper focuses on the origin of the seven peaks. Rhodamine B standard solution was used to confirmed that these peaks correspond to the light source (Xe lamp) emission in Flurolog-3 fluorescent spectrometer. The excitation spectrum of Eu2+ in SrS: Eu2+, Dy3+ was corrected with Rhodamine B. It was found that the corrected spectrum was quite different from the experimental spectrum.

The true stress-strain curves of 2198-T3 aluminum-lithium alloy in three different orientations (0°,45° and 90°) were measured by uniaxial tensile test. Finite element analysis technique was used to simulate the forming process of irregular cup, and the hydro forming experiments were conducted with YB32-100t press machine. The results showed that the key forming parameter-n values were similar in three orientations. Simulation results illustrated that the thickness of the blank reached the lowest value at the round corner. Experimental results verified friction was a significant factor to manufacture a qualified competent. Meanwhile, the experimental results agreed well with the simulation ones. The practical thickness distribution of 2198-T3 irregular cup along the section line was coincided with simulation.

Wind turbine power characteristic curve is not only an important indicator to assess the performance of wind turbine and evaluate the power generation performance, but also an important factor of impacting the wind power prediction accuracy. In this article, an identification method of the wind turbine power characteristic curve based on the genetic algorithm is proposed. With the piecewise linearization method, the wind turbine power characteristic curve is divided into several sections that can be described by linear or quadratic functions. Data preprocessing is used to filter the abnormal points in the original data. The distance from the wind turbine operating points to the power characteristic curve is selected as the fitness function. The identification process is to look for the parameters of the linear or quadratic curves that have the shortest distance to the massive operating points. The effectiveness of the algorithm is verified through the computation of a wind farm data.

Purpose To investigate the cariostatic effect of six restorative materials in vitro. Method Enamel blocks of bovine incisors were restored with six restorative materials (a conventional GIC, FujiIILC, Compoglass F, BeautifilII,Charisma and an experimental fluoride releasing resin composite) respectively with a gap of 270μm in width between each filling material and enamel. Then all restorations were immersed in a partially saturated acidic buffer solution at 37C for 3days. The surface enamel microhardness of the enamel blocks were measured before and after demineralization and the depth of enamel demineralization was measured using polarization microscope for each restoration.Results Enamel surface hardness of all restorations demonstrated significant reduced after demineralization ( pBeautifilII≈Compoglass F≈Experimental Resin>FujiIILC>GIC ( p> 0.05). The order of the depth of enamel demineralization along the surface and the interface near the gap for the 5 materials is as follows: Charisma >BeautifilII≈Compoglass F ≈Experimental Resin>FujiIILC>GIC (P > 0.05). Conclusion The new fluoride releasing and recharging composite resin has the ability to prevent recurrent caries around the restoration and its ability is comparable to compomer materials.

The objectives of this in vitro study is to display the overall planar morphology of leakage at resin-dentin interface using ammoniacal silver nitrate as tracer. Twelve human extracted third molars were used and the occlusal enamel of each tooth was removed. All teeth were divided into four groups of three teeth each and bonded with one of four adhesives (Prime&Bond NT, Adper Prompt, Xeno III, Clearfil S3 Bond) and then a composite resin crown was built up. After storage in water (37°C) for 24 h, all teeth were vertically serially sectioned into stick-shaped specimens the bond interfaces. All specimens were immersed in ammoniacal silver nitrate solution, followed by developing solution and subjected to tensile test and the fracture surface were observed with a SEM. The overall planar morphology of leakage at resin-dentin interface appeared to be various tree-like figures, with character of stem-like portion in the periphery and extending from the periphery to the center of the fractured surface and stretching out a lot of branches. Prim&bond NT presented a couple of big tree-like silver deposition extending to center besides many short tree-like figures located along the periphery. Adper Prompt showed short tree-like figures with many branches. Xeno III displayed tree-like figures with thinner stem portion and more branches. Clearfil S3 Bond presented many short shrub-like figures with fewer branches.

By installation of GC-02 Bluetooth module,inter-provincial express train TVM is relatively mature at present, so that passengers can, in accordance with the agreement, choose the available time, trains, departures and terminals and seats with their own Bluetooth-enabled phone. Hence, it will greatly reduce the time on the vending machine. In peak hours, passengers will experience “parallel virtual queuing”,and benefit from the less queuing time and fast tickets buying.

Information processing is of essential importance for an effective financial early warning model. In order to design the model of financial early warning for listed companies, we selected the 120 listed companies as research samples, chose the necessary information and relatively financial indexes and detected them by K-S normality test, then separately analyzed the results by One-Sample T test and Nonparametric Test. Through the discriminant analysis to the correlation analysis, we can identify the independent variables of logistic analysis, introduce in the quadratic term and cross term for logistic regression analysis. Applied the model in financial crisis prediction of the listed companies in China, the empirical results indicate that the prediction accuracy is 87.4%. The model from relatively information and financial index provides a kind of early warning method, which is simple practicable and scientific, for estimating the business status of a company.

In order to ensure the safe operation of the ship in the medium-voltage grid, transformer protection is particularly important. Using Matlab/Simulink, this paper established transformer and its differential protection simulation model of the medium-voltage ship. To achieve differential protection function, this paper uses the M-file to program the differential protection S-function. The simulation results indicate that the differential protection models can achieve their protection functions and have better quick-acting and stability.

The global economic and social developments depend largely on fossil fuels nowadays. To cope with energy crisis and environment problems caused by consumption of fossil fuels, the renewable energy exploitation is an alternative path. As one kind of renewable ocean energy which can be applied into production, tidal energy is mainly utilized in electricity generation. China has abundant tidal energy resource, which mainly distribute in the southeast coastal areas where power supply is insufficient. China's tidal power generation started in 1958, and some experience and technologies have been accumulated from the long-time history of tidal power station construction and operation. At present, China’s tidal energy’s development and utilization are still in low level, and remain plagued by several challenges, such as high cost, and insufficiency of preferential policies and regulations. While, China's tidal power generation must be very promising in the foreseeable future, with a great deal of attention paid to the utilization of renewable energy and the perception of sustainable development.

With the increase in demand for electricity in inland provinces because of economic growth, construction of inland nuclear power plant (npp) has become a trend. Inland npps discharge into the water bodies where may be some drinking water sources downstream, so the impact of radioactive liquid effluent released from inland npps is far greater than that come from coastal npps, and it is necessary to know the hydrodynamic characteristics of the water bodies clearly. A proposed inland npp near the Yangtze River and another near a reservoir were simulated by Cormix respectively. Then analyse the simulation results and suggest to use diffusers to help to initial mixing of contaminants in near field.

The Auto-Proving-Ground test cant reveal all problems of testing vehicles. Establishing a more suitable and accurate test for reliability index of auto-mobiles has become an important issue. The operating states data of coaches that running from Hefei to Zhengzhou has been collected in this paper, principal component analysis, and clustering analysis were then used to obtain the main factors that necessary for researching intercity bus reliability. The road condition, the ratio of idling, acceleration, deceleration and constant velocity has been determined based on the real drive condition. The acceleration in the y direction also has been taken into consideration when the bus steer. Based on the factors we improve the effectiveness and rationality of tests, which is in favor of building the system of rapid detection and evaluation for vehicles reliability.

Rolling schedule is an important parameter in high strength production of cold tandem rolling process, and the reasonable rolling schedule setting is important to cutting down energy consumption of unit, endurance of product stable and improving flatness as well as surface quality of sheet. Consequently, according to lots of theory research and spot experiment, taking relative balance of rolling force, flatness well of finished sheet and minimal rolling power as the control goal, the multi-object model for high strength sheet is built. Simultaneously, considering that PSO algorithm has shortcomings of initial randomness and premature convergence, the ACPSO algorithm is proposed which takes advantage of periodicity of the chaos motion and the inertial weight is adjust according to premature convergence extent of particle swarm and accommodate value of individual. It can improve convergence speed and accuracy. When the improved PSO algorithm is applied into rolling schedule model, it has good effect in spot experiment and productive practice.

The objective of this study was to examine the effect of different levels of catfish bone paste to flour on the physicochemical, textural and crumb structure properties of steamed bread. Six different levels (0, 1, 3, 5, 7,10 %) of catfish bone paste to flour were used in the formulation of the steamed bread. The results showed that the weight loss and TTA of steamed bread decreased with an increase in the levels of the catfish bone paste. On the other hand, the pH increased with an increase in the levels of the catfish bone paste. The specific volume, hardness, chewiness and gas cell structure in the crumb of steamed bread with catfish bone paste at 5% supplementation level were better. Thus, a value of 5% catfish bone paste was considered a better level for incorporation into the steamed bread.

Using microwave technology,establish a best destroying enzyme condition that can make peroxidase (POD) and polyphenoloxidase (PPO) lossing of activity. Enzyme activity of PPO and POD were determined by guaiacol colorimetric method and catechol colorimetric method under the condition of six different microwave time and five different microwave power. Complete deactivation of POD and PPO was achieved when microwave treatment of the chestnut kernel to 640W/60s were combined. Under these conditions, the color and flavor of the product were retained,which is the best destroying enzyme condition in chestnuts by microwave heating

Objective: To evaluate the fluoride release rates and fluoride recharge capability of a experimental resin composite, a compomer, a giomer and a resin-modified glass ionomer cement. Methods: Ten disc specimens of each material were prepare and polished with abrasive paper, followed by clearing with oil-free compressed air jet. The specimens were placed in a plastic vessel containing 5ml deionized water immediately after fabrication. Each specimen was removed and put to a new a vessel containing deionized water each day, and the sample solution was test for fluoride concentration each day using a compound fluoride ion selective electrode and a conductivity meter. All specimens were removed from container after 28 days and were recharged by immersing in a fluoride foam solution for four minutes. Then fluoride release from these recharged samples was measured daily for 7 days. Recharge was repeated three times. Result: Fuji II LC demonstrated the highest fluoride release ( p p

Purpose: The aim of this in vitro study was to investigate effects of consistency of resin composite and insertion techniques on the formation of porosity or inclusion of air bubbles in resin composite restorations. Materials and Methods: Three resin composites (Tetric Ceram HB, Tetric EvoCeram and Prodigy) were selected to represent high, intermediate and low viscosity, respectively. Simulated Class I cavities prepared in acrylic resin blocks were restored with one of the composites using both hand-instrument insertion and injection insertion techniques. The restorations were sectioned longitudinally and microscopically examined for the presence of porosity. Results: The materials of low (Prodigy) and high Tetric Ceram HB) viscosity exhibited a significantly less porosity than the material of a mediate viscosity. The porosities of Prodigy and Tetric Ceram HB restorations were comparable regardless of the insertion technique. Tetric EvoCeram restorations inserted by the hand technique contained more porous inclusions than those inserted using the injection technique. Conclusion: Porosities inside resin composite restorations apparently arose during the filling process, and the consistency of resin composite influenced the porosity formation of the composite restoration. Injection insertion was not found necessary to reduce porosities.

t was reported that more than 1 billion tons of straw is produced in China each year. Because of difficulties in degradation, farmers usually burn the straw by themselves. In this paper, corn stover was chosen to represent straw and microorganisms were used to produce organic fertilizer in order to render the straw harmless. Also organic fertilizer can improve soil quality and reduce the dosage of chemical fertilizers. 5 Microorganisms which were Bacillus subtilis, Bacillus licheniformis, Bacillus thermophiles, Pseudomonas stutzeri and Zymomonasmobilis were selected by high CMC enzymatic activity.Then, a multi-bacterium was designed which could improve fermentation efficiency. To save energy, water resources and improve fermentation efficiency, the fermentation device in the lab was improved.

The circular economy (CE) is a new development strategy for China to alleviate the contradiction between rapid economic growth and the shortage of raw materials and energy. As the basic material, steel is a key driver of the world's economy. Therefore, it is essential to set up CE indicators system to understand the mechanism of steel resources role in the circular economy. In this paper, a national level material flow evaluation framework based on CE theory is presented at the first. Then steel resources national lifetime cycle diagram is built based on dynamic Material Flow Analysis (MFA) method considering the steel lifetime circular flow characteristics. Under the guidance of this diagram, the material flow results of various stages (such as production process, fabrication & manufacturing process, in-use process, etc.) of steel lifetime cycle between 2001-2010 in China is obtained, including the end-of-life scarp amount of nine downstream industries. The results indicate that China steel resources has made gratifying achievements in improving productivity, reducing energy consumption and related pollution emission, but the degree of overall circulation remains to be improved urgently. In the end, a sketch of the future relevant policy recommendations are provided.

This paper evaluates the performance of the networked munitions communication and localization. The key requirements of networked munitions are proposed and analyze the possible technologies for localization. The hardware for communication and localization are selected and designed, the software scheme are illuminated according to the hardware and the project. The experiments prove that the design is effective and satisfies the application of networked munitions.

After three decades of rapid development in reform and opening, Guangdong encounters a bottleneck of resources and environmental constraints, in which its reflection should be learned by Chongqing, thus to prevent going into the same Crossroads after development of electronic information industry in future. Guiyu Phenomenon is a gradual process, in which, the electronic waste disposal has brought purely economic interests, and environmental and ecological crisis was reflected at the same time. In Chongqing, this painful lesson should be prevented in advance in electronic information industry developing. The Smile Chain of Industry Profit and the Wry Smile Chain of Industry Pollution should be alert to Chongqing: if an incorrect decision of industry was choose, meager profits may be brought and serious long-term potential ecological crisis may be brought. Only by strengthening the pre-research, rational decision-making, and synchronization of environmental impact assessment and monitoring, the electronic information industry in Chongqing can go out of the trap of development.

A novel PMMA-ZrO2 composite (PZC) was prepared by resin infiltrated to ceramic method. The composite mechanical properties were evaluated and correlated to its microstructure. Partially sintered zirconia ceramics (PSZC) were made by isostatic pressing and partially sintering. Subsequently, the PZC was prepared by vacuum infiltrating prepolymerized MMA into PSZC, followed by in-situ polymerization. When PSZC-70% was used as the matrix, the bending strength, elastic modulus, and fracture toughness of the prepared composite i.e PZC-70% were 202.56±12.09 MPa, 58.71±3.98 GPa, and 4.60±0.26 MPa·m1/2, corresponding to 25.69%, 23.31%, and 169.01% improvement, respectively, in comparison with the control matrix. Among them, the fracture toughness improvement was the most prominent. According to SEM images of the fracture surfaces, each pore of zirconia skeleton was filled by organic resin contributing to the bending strength improvement. These weak interfaces between zirconia skeleton and organic resin absorbed energy and terminated the growth of microcracks which might be responsible for significant improvement in fracture toughness. This PZC material is anticipated to be a new member of the dental CAD/CAM family.

The effect of space-holder content on the porosity of sintered copper that was fabricated by powder metallurgy technique has been investigated. Carbamide was used as space-holder and the content selected was 10 wt. %, 20 wt. % and 30 wt. %. A roll mill was used to mix the copper powder and the carbamide particles with rotation speed of 160 rpm for 2 hours. The mixture was compacted by hand press at 200-350MPa and sintered under argon atmosphere at 800°C. True density of the sample was determined by a gas pycnometer. Bulk density was determined using mass and volume of the sample. Result shows that the sintered porous copper with 30 wt. % of space-holder produced the highest porosity and the lowest density. Microstructure of pores was analyzed by a scanning electron microscope (SEM) which reveals the elongated pores interconnected to each other.

In this paper, we designed an umbrella-shaped antenna for receiving low rate satellite data. The umbrella is suit for receiving satellite data in motor and emergency weather safeguard, with small volume, portable and easy to setting and debugging.

In this study, a novel phase change material was prepared by coordinating rare earth Tb3+ions to the carboxylate groups of a poly (ethylene glycol).The properties of the material were characterized by differential scanning calorimetry (DSC), infrared spectroscopy (IR) and fluorescence spectroscopy. The synthesis and characterization a novel phase change luminescent Tb-PEG/SA material were described in this paper. The result show that this modified PEG material show both good phase change properties and excellent luminescent properties.

A sensitive and selective method for the determination of diethylstilbestrol (DES) by fluorescence immunoassay (FIA) was established on the basis of competitive immunoreaction. The complex of avidin conjugated by quantum dots (QDs-avidin) was regarded as a probe in this system and the avidin-biotin system as the signal amplification system. After optimizing the conditions of immunoreaction such as the time and temperature of incubating, the pH of the buffer solution, the concentration of the reagent and so on, the linear range and the limit of detection of DES were 0.01-2000 ng·mL-1 and 4.5 pg·mL-1, respectively. The method was applied to determine DES in flesh of chicken, with the percent recoveries in the range of 81.0%-109.8%.

Combining with welding and numerical control technology, welding automation technology has brought the new development for welding equipment industry. This paper mainly aimed at automatic welding process needs for intersecting line of T-type tube, developed a practical automatic welding machine of T-type tube intersecting line, used the PCL893 movement control card as the core control unit, realized whole rotary feed of welding head and front and rear feed of the torch, etc. Integrating with mechanical cam and digital cam, the work achieved space fitting of saddle-shaped weld track so as to realize automatic welding process, imitate the manual welding process of space curve, reduce labor intensity, improve the efficiency of welding and quality.

The winding inductance is an important parameter to analyze the characters of the slotless PM motor. In this paper an analytical energy method is introduced. By the method, the conductor inductance in the slotless motor can be figured out. Furthermore, an analysis method of the end winding inductance is presented in this paper. The calculation results are identical with the results of FEM and the actual measured value. It proves the calculation method of winding inductance in slotless motor is valid.

The local equilibrium in the kinetic process of dissolution is addressed. The measured dissolution kinetic data of Ag on Cu(111) surface are well fitted by the modified Darken model. Using the obtained fitting parameters, the discontinuous transition of Ag surface concentration against the bulk concentration of the neighboring layers deduced from the local equilibrium model is quantitatively interpreted.

It’s not easy to control the processing route of alien solid wooden furniture’s process, which is based on the CNC processing center. And the edition of the cutting tool path is complex. This paper puts forward the optimization design method of section layout, and determines the method of the cutting tool path through choosing proper cutting tool and adjusting the parameters. This paper also verifies the effectiveness of this method, taking a head of Europe type bed processing line as an example.

Compositions that related to the secondary haze compositions in clarified apple juice were studied. Pressing treatment, pasteurization and enzymatic treatment were mainly investigated. Turbidity, contents of phenolics components, and that of soluble proteins in three batches of apple juice were monitored at intervals during the processing procedures. Pressing treatment resulted in increasing the turbidity and contents of total phenolics, condensed tannins, soluble proteins, but decreasing the level of low molecular- weight phenolics in apple juice. Pasteurization had effects on increasing the level of turbidity and decreasing the level of soluble proteins and had little effects on the level of phenolics components in apple juice. Enzymatic treatment resulted in decreasing the turbidity and the levels of catechin, epicatechin, chlorogenic acid, procyanidins B2 and condensed tannins and increasing the level of soluble proteins in apple juice. It will help to control the secondary haze formation in apple juice production.

The relationship of adsorption characteristic about active carbon and the haze in clarified apple juice was investigated. Particle size and addition and adsorption temperature of active carbon were studied.0.18mm particle size with the biggest specific surface area and 0.075mm particle size with the widest microspore distribution of active carbon lowered the turbidity and contents of haze active protein and that of haze active phenolics. Contents of haze active protein and that of haze active phenolics in apple juice were decreased by increasing the adding amounts of active carbon. High temperature of adsorption showed the positive relationship with volume of haze active phenolic and the negative relationship with volume of haze active protein. Particle size of active carbon with 0.18mm or 0.075mm and addition of 15g/kg and adsorption temperature with 50°C are chosen in reducing the haze in apple juice. Absorbability of active carbon has great effects on the haze of apple juice.

The discontinuous transition of surface concentration due to the change of bulk concentration in isosteric/isothermal surface segregation has been discussed quantitatively according to the modified Darken model. The criteria for observing the discontinuous transition in surface segregation has been derived on the basis of the Bragg-William expression.

The character of COD release in the sediment of Tang He Reservoir was studied under the condition of different concentrations, temperatures, pHs, disturbances, and dissolved oxygen through indoor simulation experiment. It was concluded that sediment could adsorb more organic pollutants when the river was at a higher concentration; whether the temperature was raised or lowered, the COD emission all increased, so the maintenance of temperature could inhibit the release of COD in water; the water stable at the pH of 8; disturbance significantly increased the released quantity of COD; low dissolved oxygen could promote release of COD. The study can provide scientific basis for comprehensive treatment of Tang He Reservoir.

Sampled with the pigments extracted from Chinese chestnut shell by alkali solution, chromaticity with protein and starch and chromaticness and red index are related to. The characteristics were compared with that of the standard caramel pigment. Methods were used by spectrometer and colorimeter. Compared with caramel pigments, better chromaticity and stability with starch and protein, lower chromacticness and higher red index of pigments in shell were shown.

First selected weft plain and plain weave fabrics as samples, and joined these samples by four thread overlock stitch in different ways and four stitch densities, then tested tensile properties of the fabrics to analyze sewing properties of the fabrics, finally found variation of the fabrics properties.

V2G technology achieves a two-way interaction of the grid and electric vehicles (EVs), it makes plug-in hybrid electric vehicle (PHEV) be able to access grid and participate in grid scheduling. By V2G technology, PHEVs can provide FM and spinning reserve ancillary services such as economic dispatch. With the extensive use of plug-in hybrid electric vehicles (PHEVs), its important impact on charge and discharge process will be the grid safe and economic operation. Firstly, the article proves the V2G discharge capacity of a normal distribution from the theory, and based on which to establish a stochastic economic dispatch model. The results which obtain by using the IEEE 14 node system simulation show that this conclusion of the constructed model is feasible and effective, and the conclusions that the V2G node optimal active output power and minimum scheduling cost expectations are proportional to the the V2G discharge capacity expectations are also obtained.

In the process of rapid urbanization, there are many challenges people have to face. In this study, typical human settlements in Bali Island in Southeast Asia were introduced, and impact of ecological and cultural factors on human settlements in this region were especially investigated, aiming to provide inspirations to solve the problems related with rapid and uncontrolled urbanization in many other parts in Asia. Impacts of ecological and cultural aspects on style of housing building and private gardening and on public spaces were analyzed separately. It was concluded that ecological and cultural factors contribute much for both the preservation of context in traditional human settlements styles and preservation of ecological background in Bali Island.

The division of geohydrologic unit is the base of regional hydrogeologic research. Based on the weakness of the traditional method of dividing geohydrologic unit, the division method of geohydrologic unit based on hydrochemical characters of groundwater is put forward. The division of geohydrologic unit on Cambrian limestone in Pingdingshan coal field is done with Fuzzy C-Means Cluster, and the result is satisfying. It provides a new theoretical method for division of geohydrologic unit.

Based on high density polyethylene (HDPE) as supporting and encapsulating materials, paraffin wax as energy storage materials, HDPE/paraffin composite for phase change materials was prepared in the paper. In order to low leakage rate of HDPE/paraffin composite for phase change materials, the influencing factors of leakage rate of HDPE/paraffin composite, such as temperature of mixing, time of mixing, different content of DCP, rate of cooling, were studied. The results indicated that low leakage rate of PCM could be prepared.

A novel glycoprotein PLG-3 was obtained from the cultured mycelia of the edible mushroom Phellinus linteus AML1101 by isolating with cold water for 24 h and fractioned with DEAE-Sephrose Fast Flow column. It exhibited potent antiproliferative activity on A549 cells and HepG2 cells in vitro. After 24, 48, 72- h treatment with PLG-3, IC50 values of A549 cells and HepG2 cells were 45.77, 24.09, 16.54 μg/L and 47.78, 26.73, 18. μg/L, respectively. PLG-3 had a molecular weight of 2.5×104 Da, and consisted of approximately 85.5% of protein and 13.7% polysacchrides. It was composed of arabinose, xylose, mannose, glucose and galactose with a molar ratio of 1.46: 2.22: 7.74: 1.29:0.61.The obtained results proven that PLG-3 was a protein-dominant glycoprotein with singificant antiproliferative activity.

The physical and sensory properties of the steamed bread with different refrigerated processes (frozen steamed bread, pre-steamed steamed bread, proofed-frozen dough, fermented-frozen dough, frozen dough and cold storage dough technology) were compared with fresh steamed bread. The specific volume, spread ratio, whiteness and the parameters from texture profile analysis (TPA) were used to evaluate the physical properties. The results showed that technology of cold storage dough was the best for the steamed bread. Technology of frozen dough and frozen steamed bread were better technology. Technology of pre-steamed steamed bread, proofed-frozen dough and fermented-frozen dough which were used in the industry of bread commonly were not fit for steamed bread.

In this paper Yuan River was taken as an example of the southern river, and Taizi River was an example of the northern river. Based on the contents of ammonia nitrogen, total nitrogen, total phosphorus and COD in the sediments, the distribution of pollutants in the sediments along the Yuan River and Taizi River were analyzed; When the pollutant contents of individual sections were particularly higher, the pollution sources were studied; Through the contrast of pollutants contents in sediments between Yuan River and Taizi River, the contents of Taizi River were higher 2-5 times than Yuan River. Then the causes were summarized from temperature,hydrological condition, discharge of industrial and domestic wastewater and sand contents.

To solve water disasters of coal seam bottom in the 8th coal mine, with the analysis on the bottom aquifer characteristics, the water inrush coefficient method was applied to evaluate the dangers of the aquifer floor and to the dangers division of water inrush. In combination with the karst fracture development conditions of the aquifer, we designed the water prevention and control plan of the limestone water under the seam floor. All the schemes set the basis for the mine safety production.

Based on general characteristics of the Wumishan reservoir, the hydrogeology model is founded. And the problem of no more space for adding reinjection wells, the mathematical descriptions and influent of hydrothermal transportation, thermal break-through and the flow feed path with the different fracture zone were emphasied. According to simulat ion of the different models, a new ideal strategy about the reinjection wells was put forward, which can be set in the periphery of geothermal zone. And more heat can be extracted from the reservoir rocks through the reinjection activities. The pressure and temperature field of the reservoir will be controlled even though the injected cool water moves forward to the product zone, the water level and temperature field can be more stable with the reinjection models.

In fluid mechanics, how to solve multiple solutions in ordinary differential equations is always a concerned and difficult problem. A particle swarm optimization algorithm combining with the direct search method (DSPO) is proposed for solving the parameter estimation problems of the multiple solutions in fluid mechanics. This algorithm has improved greatly in precision and the success rate. In this paper, multiple solutions can be found through changing accuracy and search coverage and multi-iterations of computer. Parameter estimation problems of the multiple solutions of ordinary differential equations are calculated, and the result has great accuracy and this method is practical.

The strip thickness control system is difficult to establish an accurate mathematical model, and traditional PID control strategy has a poor adaptive ability, so the effect of control is always not satisfying. According to the problems above, a new control strategy of self-tuning PID controller based on RBF neural network whose parameters are optimized by PSO algorithm is proposed in the paper. The control method integrates advantages of RBF neural network as well as PID controller and good global search capability of PSO algorithm. The simulation results indicate that the method not only improves control performance and dynamic quality, but also has strong self-adapting ability and robustness. It achieved a very good control effect when used in strip thickness control system that proved the correctness and effectiveness of the control method.

Systems as diverse as genetic networks or the World Wide Web are best described as networks with complex topology. A common property of many large networks is that the vertex connectivities follow a scale-free power-law distribution. This feature was found to be a consequence of three generic mechanisms: (i) networks expand continuously by the addition of new vertices, (ii) new vertex with different number edges of weighted selected that connected to different vertices in the system, and (iii) new vertices attach preferentially to sites that are already well connected. A model based on these three ingredients reproduces the observed stationary scale-free distributions, which indicates that the development of large networks is governed by robust self-organizing phenomena that go beyond the particulars of the individual systems.

CZTS thin films are fabricated by sulfurizing co-sputtered metallic precursor CuZnSn layers under H2S atmosphere. The precursor layers are Cu-poor, Zn-rich deposited and the fabricated films are about 2 µm in thickness. A closed-tube process is preferred with regard to its producing large closely pack grains with smooth surface. XRD and Raman confirm the CZTS structure and the impurities on the surface are removed after suitable chemistry treatments. The band gap of the CZTS is determined to be 1.48 eV by extrapolation. Some more CZTS films are product with slightly changed parameters, sulfurization time, temperature and concentration of H2S, respectively. It is supposed that beside sulfurization time, the temperature could be more significant than concentration of H2S in the closed system.

With the accumulation of solid waste in developing countries, sites of closed landfills have attracted attentions, which can be sorted as one typical brown field in urban area. Taking closed municipal solid waste landfills as examples, case study for turning brown land into green space in Europe and USA was carried out, based on which, suggestions on the ecological regeneration of brown land in China were put forward. It was put forward that for closed landfill constructed in the earlier days, the reliable procedure for the site generation should be reclamation. If it is not possible to carry out the reclamation engineer at present, establishment of trees on the top soil of closed landfill, in other words, eco-regeneration can reduce the negative effects of landfill as far as possible. For the developing countries, reduction, stabilization and recycling of solid waste should be the final solution for solid waste.