bluuebunny/crossref_metadata_2025 huggingface dataset:
Research of High Performance Closed Loop Control System for Stepper Motor
Authors: Xu Zhao Hua , Xie Xiao Hui , Ma Cui , Sun Qiang , Du Ru Xu
Published: March 2013

A control system of double closed-loop for two-phase hybrid stepper motor which includes speed closed-loop and current closed-loop is established on the basis of fuzzy-PID control algorithm, space vector pulse width modulation (SVPWM) method, space vector conversion and mathematical modeling of stepper motor. In the control system, the stepper motor model is established according to the mathematic model; the current and speed of stepper motor are controlled in feedback by the adopting fuzzy-PID control algorithm; the space vector conversion is carried out in the current/voltage conversion section, and the space vector pulse width modulation method is used to produce pwm wave. The performance of the doubled closed-loop control system for stepper motor is analyzed by the powerful modeling and simulation function of MATLAB/Simulink. The simulation results show that the control system has favorable control performance and dynamics characteristics.
A New Approach for Prioritization of Failure Mode in FMECA Using Encouragement Variable Weight AHP
Authors: Zhang Shu Zhong , Zeng Qin Da , Zhang Gong
Published: March 2013

The traditional failure mode, effect, and criticality analysis (FMECA) uses risk priority number (RPN) to evaluate the risk level of a failure mode. The RPN index is calculated by multiplication of severity, occurrence and detection factors. The most critically debated disadvantage of this approach is that various combinations of these three factors may produce an identical value of RPN. This paper reviews the drawbacks in traditional FMECA and proposes a new approach to overcome these shortcomings. The proposed approach evaluates risk of failure mode by encouragement-variable-weighted analytic hierarchy process (EVW-AHP) that can prioritize failure modes even if two or more failure modes have same RPN. An example is provided to show the potential applications of the proposed approach and the detailed computational process is presented. The results based on the case study show the proposed new methodology solves the limitations of traditional FMECA approach and is feasible.
Application of Silicon Carbide Diode in Ultrasound High Voltage Pulse Protection Circuit
Authors: Zhou Shi Yuan , Zhang Kai , Xiao Dinguo , Xu Chun Guang , Yang Bo
Published: March 2013

SiC diode (Silicon Carbide Diode) is a newly commercial available Schottky barrier diode with zero reverse-recovery-time, which is a perfect candidate for fabricating high voltage pulse protection circuit in ultrasonic transceiver system. With SiC diode’s high performance, the circuit can deliver 400 volts or higher voltage protection level, which is not an easy job for other kind of diodes. In this article, the theory of diode-bridge protection circuit is briefly discussed, and a SiC diode-bridge protection circuit was fabricated, and some experiments has been done to verify the feasibility of using SiC diodes in diode-bridge protection circuit.
An Effective Method for Defects Detection in Radiographic Images of Welds Based on Edge Detection and Morphology
Authors: Guo Wen Ming , Chen Yan Qin
Published: March 2013

In the current industrial production, as steel weld X-ray images are low contrasted and noisy, the efficiency and precision can’t be both ensured. This paper has studied three different edge detection algorithms and found the most suitable one to detect weld defects. Combined with this edge detection algorithm, we proposed a new weld defects detection method. This method uses defect features to find the defects in edge images with morphological processing. Compared to the traditional methods, the method has ensured detection quality of weld defects detection.
Elimination of Multi-Points Support Effects in Modal Testing
Authors: Ren Jun , Bi Shu Sheng , Wang Wei , Zong Guang Hua
Published: March 2013

The measured Frequency Response Functions (FRFs) often have errors due to the support effects in free-free modal testing. In [1], elimination of support effects from the measured FRFs has been investigated and both stiffness and damping have been considered in support conditions. However, the method is only applicable for single point support occasion while the test structure is usually supported from more than one location in a practical testing. Therefore, this paper further investigates this method to extend its application to multi-points support conditions. Firstly, general formulas of removing the multipoint support effects from the measured FRFs are derived based on the dynamic substructure method. Then a simulated modal test of free-free beam with two points suspension is proposed to verify this method. Finally, the performance of the method is investigated with simulated noisy data. It is shown that the proposed method is effective in removing support stiffness as well as support damping from the measured FRFs as long as the measured data are not heavily contaminated by the noise.
Contactless Charging Technology of Electric Vehicle
Authors: Huang De Xu , Lv Xiao , Lu Shou Yin , Tan Lin , Zhao Jin Long , Qi Hun , Wang Tong Bin
Published: March 2013

The electric vehicle has the advantages of energy-saving, environmental protection, low-carbon economy etc, and the charging system is an indispensable subsystem of electric vehicle. It’s the charging long time and inconvenience of traditional charging mode that makes contactless charging system become the trend of future electric vehicle charging technology development. Firstly, this paper introduces the principle of contactless charging of electric vehicle, analysis the three kinds of charging mode, and then combined with the development of domestic and international situation, puts forward some inevitable problems in reality. Finally, discusses the contactless charging device for electric vehicle application.
Influence of Isoamylase Supplementation on Performance and α-Amylase Activities of Broilers Fed Maize-Soybean Meal Diets
Authors: Liu Ling Yun , Sun De Fa , Li Jun Jun , Tang Xiang Hua , Mu Yue Lin , Huang Zun Xi
Published: March 2013

An experiment was conducted to study the inﬂuence of isoamylase supplementation to maize-soybean diets on productive performance and amylase activities of broilers from 1 to 42 d of age.The results showed that different dose of isoamylase（300g/T,600 g/T,900 g/T, containing 3000IU of isoamylase/g）in the maize - soybean meal diet significantly affected the performance of broilers within 1-42 days. Within 1-21 days , the average daily gain(ADG) of experimental groups( experiment I (E I) experiment II (E II) experiment III (E III) ) improved by 3.2% -10.32%(P>0.05) compared with the control groups(negative control(NC) and positive control(PC)), average daily feed intake(ADFI) improved by 0.63%-7.43%(P>0.05), while feed conversion ratio decreased by 0.55%-4.43%(P>0.05); Within 21-42 days , the ADG of experimental groups decreased by 1.38%-4.84% and ADFI by 11.89%-15.58% (P<0.05), feed conversion ratio by 5.41%-7.54% compared with that in the NC group; Within 1-42 days , the ADG of experimental groups improved by 0.54%-4.06%(P>0.05), while ADFI decreased by 0.75%-11.83% (P<0.05), and feed conversion ratio by 3.97%-7.52% (P>0.05) compared with those in the negative control. Isoamylase supplementation influenced amylase activity of various parts of the chyme in digestive tract and the tissues of small intestine and pancreas. 21 d, the amylase activity in experimental groups improved by 4.67%-79.29%(P<0.05) compared with PC, α-amylase activity in the majority experimental groups were lower than PC group, but the difference was not significant(P>0.05).
Adsorption Characteristics of Phenol in Aqueous Solution by Pinus massoniana Biochar
Authors: Deng Guo Zhi , Wang Xue Yuan , Shi Xian Yang , Hong Qian Qian
Published: March 2013

The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.
Adsorption of Cr(VI) from Aqueous Solution onto Lab-Made Mesopore Activated Carbon
Authors: Fan Ming Xia , Wang Kun , Wang Ya Zhou , Yu Dan Qing
Published: March 2013

In the present investigation, lab-made mesoporous activated carbon (MAC) was prepared for testing the ability to remove Cr(VI) from aqueous solution. The influences of several operating parameters such as pH and temperature on the adsorption were investigated. Solution pH is found highly influencing the adsorption and low pH is favorable for Cr(VI) adsorption. The adsorption of Cr(VI) is enhanced with increased temperature. Thermodynamic parameters were evaluated and the adsorption was endothermic. Several adsorption isotherms include Langmuir, Freundlich and Dubinin–Radushkevich(D–R) were used to fit the equilibrium data. The adsorption kinetic data of Cr(VI) were analyzed and was found fitting well in pseudo-second order equation. The lab-made MAC is found to be effective adsorbent for removal of Cr(VI) from aqueous solutions.
Experimental Study on Seepage and Purification of Modified Fly Ash as the Substrate of Constructed Wetlands
Authors: Guo Meng Fei , Xian Ping , Liu Xi , Yang Long Hui , Ning Cun Xin , Liu Ya Qing
Published: March 2013

An experiment on seepage and purification by modified mixtures of power plant fly ash and soil at different mass ratios was studied for developing a novel high efficient substrate of constructed wetland. The results showed that the soil’s osmotic coefficient can be improved by mixing fly ash and soil. The different mass mixing ratios of ash and soil had little effects on the removal of total nitrogen in wastewater, comparatively they had positive effects on the removal of total phosphorus and ammonia nitrogen. The phosphorus’s removal efficiencies were maintained at 81.94%~89.68%. The average removal efficiency of ammonia nitrogen was 85%, and the 4:6 level obtained the best removal efficiency, which was 93.41%. The different mass mixing ratios of ash and soil had obvious effects on COD removal of wastewater. The 1:9 and 0:10 levels gained higher removal efficiencies than others, whose removal efficiencies were 95.16% and 95.39%, respectively.
Nano Fe3O4/Polymerization Ferric Chloride Composite Materials in the Application of Hydroxybenzene Wastewater
Authors: Xie Yun Cheng
Published: March 2013

Fenton’s reagent method optimizes conventional wastewater oxidization treatment technologies to remove biodegradable organic matter that cannot be removed. In this paper, ferric chloride hexahydrate, iron (II) chloride tetra hydrate, and ammonia act as raw materials in preparing the nano-iron oxide / polymer composite material ferric chloride. Self-made composite treatment of phenolic wastewater in the reaction time 120min,0.076mol/mL composite dosage 3ml (concentration), H2O2 concentration of 15% (dosage), Fe2 + / Fe3 + ratio of 2:1 for phenol removal of the best wastewater.
Using Gin Adsorption Model for Assessing the Influence of Algal Powder Bleach Process in Cu(II) Adsorption
Authors: Chang Shui Ping , Lee Yi Chao , Lee Chih Sheng , Kao Nien Hsin
Published: March 2013

The Cladophora and Spirogyra algae examined in this study belong to the Chlorophyta division. Macro filamentous algae, which are widespread in fresh water worldwide, have high potential to be developed as biological materials because of their large biomass and availability. In this study, we collected fresh algae from where they grew and produced bleached and unbleached algae powder using to adsorb Cu(II) ion solution. After the biosorption process, we noted the following four significant findings: (i) The functional groups and binding sites in the produced algae powder were affected, causing variations in the amount of copper adsorbed. The variations resulted from differences in the cell structure, the cell wall thickness of Cladophora and Spirogyra algae, cell composition, and the types and amount of epiphytic algae. (ii) Common bleaching procedures using glacial acetic acid influenced the binding sites of the functional groups and the biomass of the produced powder. Because of the bleaching, the amount of copper adsorbed by the Cladophora powder declined by 14.2%, and by 15.7% for Spirogyra powder. (iii) The carbonyl and hydroxyl groups of unbleached powder were the main elements affected during the bleaching procedures. Examining whether the biosorption experiment results fit Gin’s biosorption model, we found that the biosorption amount and equilibrium reaction of the two bleached algae powders were inferior to that of the unbleached algae powders. (iv) The bleaching procedure using glacial acetic acid was not suitable for producing algae powder to use as an adsorbent for metal ions.
Study on the Effects of Wetland Plants on DO in Domestic Sewage
Authors: Lu Min , Liu Shun Teng , Kang Wen Feng , Li Ke Ke , Zhao Jie , Liu Gong Sheng
Published: March 2013

By adopting the constructed wetland system of surface flow, the purification effects of different residence time of wastewater, different constructed wetland plants and their synergistic effect are studied in DO disposal in living wastewater. The results show that the best plant combination in purifying DO is that of Phragmites communis and Typha oriental,followed by that of Phragmites communis, and that of Arundo donax and Typha oriental is lowest.
Study on Treatment of Polytetrahydrofuran Wastewater by Iron-Carbon Micro Electrolysis
Authors: Tian Xi , Huo Ming Xin , Bian De Jun , Ai Sheng Shu , Ren Qing Kai
Published: March 2013

The wastewater produced from the polytetrahydrofuran (PolyTHF) was treated with iron-carbon micro electrolysis process. This paper had studied the COD removal efficiency influences of primary PH value, reaction time, the quality ratio of the iron-carbon, the quality and volume ratio of Fe-wastewater. The results show that when pH value is 3, the quality ratio of the iron-carbon is 11 and the quality and volume ratio of Fe and wastewater is 17 with contact time of 90 min, the wastewater COD removal rate can reach as high as 95.0%.
Study on Microwave Combined with Active Carbon for the COD Remove of Amoxicillin Wastewater
Authors: Feng Quan Li , Wang Xue Qian , Jia Yu , Ning Ping
Published: March 2013

This paper makes the amoxicillin production wastewater as the research target and uses the microwave-activated carbon to treat this kind of wastewater. The results show that 6g of the 60 purpose granular activated carbon mixed with 50ml of the wastewater that diluted 10 times and the pH value is 9 under the condition that irradiated power up to 480W and the irradiation time for 7min, the COD removal rates is up to 96.38% and the effluent COD value is 48.28mg/L.
Ecology of Diatoms in Yangtze River Basin,Hubei: Implications for Assement of Water Quality
Authors: Liu Yan , Liu Chao , Zhong Fei Fei , Hu Sun Ling , Weng Wei Xia
Published: March 2013

Diatoms are commonly used for the assessment to determine the unending rivers and lakes due to their broad distribution and its integrative nature. As it is, the corresponding evolution of species and quantity will come into being in diatom communities with the variation of physicochemical characteristics and the pollution of organic, which can indicate directly the local ecological status of aquatic environment. Water samples were collected from 32 sites in unending streams and lakes along with the Yangtze River and its cardinal branches during the mid-July last year, in order to analyze the feature of its distribution and communities. Biological diatom index BDI and the diversity index H′ were used to assess the degree of water eutrophication . We concluded that a great many biometrical indexes are valuable tools for the assessment and future monitoring of waters, combined with the ecological theory, the species of Cyclotella meneghiniana, Stephanodiscus parvus and Navicula subminiscula manifest to be very good indicators for the outbreak of eutrophication in the middle reach region of the Yangtze River and the Han River.
Visible Light Induced Photocatalytic Degradation of Rhodamine B in the Presence of Cr(VI)
Authors: Zhang Dong Dong , Qiu Rong Liang , Huang Xiong Fei
Published: March 2013

Here we report the photocatalytic degradation characteristics of Rhodamine B in the presence of Cr(VI). Some interesting results were observed during the photocatalytic process. Cr(VI) caused a deactivation effect on the catalyst due to the formation of Cr(OH)3precipitate blocking the active sites of catalyst. Moreover, a kind of red oligomer precipitate was found during the RhB degradation when Cr(VI) was presented. This precipitate was rarely reported in photocatalytic system.
Effect of Demineralization on Shale Oil Yield by Bioleaching Process of Huadian (China) Oil Shale
Authors: Zhang Xue Qing , Zhang Lan Ying , Ren He Jun
Published: March 2013

In this study, the effect of the mineral matter of Huadian (China) Oil Shale on the conversion of organic carbon of oil shale to shale oil. The bioleaching process is taken in a mixed culture of the lithotrophic bacteria Thiobacillus ferrooxidans(Tf). The aim of bioleaching process was to dissolve the inorganic matters and improve the shale oil yield. A series of temperature-programmed pyrolysis operation was performed with raw and bioleached oil shale to find the best retorting temperature, 500oC is the best temperature to retort the oil shale. The oil shale samples were detected by SEM, DG, Fischer assay test, the results show that the surface structure was significantly different from the raw sample, and the shale oil yield improved from 8.9% to 11.7%.
Study on Relationship between PM10 Concentration and Temperature Condition in Longyan City
Authors: Wang Fan , Fang Chun Sheng , Zhang Yong , Ma Zhuo , Wang Ju
Published: March 2013

Based on the temperature monitoring data and PM10 concentration data in Longyan city of Fujian Province between 2006 and 2009, the relationship of temperature changes and characteristics of PM10 pollution in the region were analyzed. Using the method of variance analysis and correlation analysis, we conducted a series of statistical analysis on temperature and PM10 concentration in order to find the relationship between them. The results showed that temperature in Longyan city was high in summer and low in winter. The PM10 pollution was more serious in winter. The results also showed that PM10 concentration had a highly negative correlation with the average temperature.
Prevention and Control of Water Pollution Based on Ecosystem Management (EM): A Case Study of Poyang Lake
Authors: Yang Qi Yong , Zhang Xin Hua , Wu Zhong Wei
Published: March 2013

The water quality monitoring revealed that the water quality in Poyang Lake is increasely degenerating in the past several years and the deterioration reasons were analyzed. The increasingly serious water pollution indicated that there were inherent drawbacks in current environmental management system of China. Therefore, the typical models of water pollution prevention and control in developed countries and China were researched. The explorations of water pollution prevention and control based on ecosystem management for Poyang Lake were reviewed, especially the practice of Mountain-River-Lake (MRL) Program in Poyang Lake Basin. At last, the challenges of water pollution prevention and control in Poyang Lake Basin was put forword such as law and policy, organization structure, participation mechanism. The researches indicated that the multiplicity and complexity of nature, humanities, society and economy in Poyang Lake determined its importance and necessity to implement ecosystem-based water environment management. In the future construction of water pollution prevention model based on integrated ecosystem management is an inevitable trend for Poyang Lake basin.
Hydrogeochemical Mechanism of the Petroleum Hydrocarbon Pollution in Karst Fissure Groundwater System
Authors: Ma Zhen Min , Luo Yun Yun , Fang Yun Zhi , Hou Yu Song
Published: March 2013

The research of hydrogeochemical mechanism of petroleum hydrocarbon in karst fissure groundwater system is important to predict the trend of petroleum hydrocarbons and the change of groundwater environment. We take the karst fissure water system as the research object, where there is a refinery. The variation of SO42-, HCO3-, NO3-, NO2-, HS- can be used as a hydrogeochemical sign of petroleum hydrocarbon pollution by analyzing the change of water quality parameters before and after karst fissure water contaminated by petroleum hydrocarbon. It has been also analyzed systematically that hydrogeochemical mechanism including desulfurization, denigration and ion exchange happen during the pollution process in the karst fissure water system. It is pointed out that the human activities have a great impact on the groundwater and changes of environment.
Spatial Distribution and Seasonal Variations of Heavy Metals in Surface Water of the Taizi River
Authors: Song Xue Ying , Hu Xiao Jun , He Miao Miao , Liang Ru Jing , Li Xin Xin , Sun Wen Juan
Published: March 2013

The contamination levels and distribution of heavy metals in surface water of the Taizi River were investigated. Samples of water were collected from upstream to downstream locations, and also from the main tributaries of the Taizi River. All samples were analyzed for arsenic, mercury, and chromium (Ⅵ). Results indicated that the metal levels of upriver sites were lower than downriver sites. The total concentrations of Cr6+ and As in dry season was higher than that in flood season. While heavy metal Hg represents the highest concentration in flood season. Compared with the permissible levels of surface water environmental quality standards (GB3838-2002), the levels of Cr6+ and As attained the first and second level, but Hg attained the fifth level. This indicated that most sites of the Taizi River have a high risk of Hg pollution in flood period.
Accumulated Characteristics of Hyperaccumulation Hibiscus esulentus L in Relation to Heavy Metals Cd
Authors: Zhang Yu , Tao Zong Ya
Published: March 2013

The study and selection of heavy metal hyperaccumulation and its planting methods and a rapid and efficient elimination of heavy metals in the contaminated environment are important research focuses to deal with the restoration and controlling of heavy metal contaminated environment. This experiment aims to explore the accumulation and accumulation characteristics of Cd on Hibiscus esulentus L in the simulation heavy metal contaminated environment achieved by pot cultivating techniques. To this end, different concentrations of heavy metal CdSO4 were used as treatment. The results indicated that with increase of the concentration of CdSO4, the accumulation of Cd in Hibiscus esulentus L was increased. When the treatment concentration of CdSO4 was at its highest (100mg/Kg), the accumulation of Cd on the above ground was 0.498mg/gDW, the highest, and that under the ground was 0.117mg/gDW. In view that the relationship of Hibiscus esulentus L of its above ground part(S) and its underground part (R) is S/R>1, experimental evidence shows that it has the basic characteristic of Cd hyperaccumulation.
Characteristics Analysis of Blending Combustion Component of the Guangxi Urban Sludge
Authors: Yang Long Hui , Xian Ping , Yang Hong Bin , Li Xiao Ping , Tang Ming , Liu Xi
Published: March 2013

The research was the character of the urban sludge burning with coal by using the elemental anaylsis, component analysis, proximate analysis and thermogravimetric analysis. There is a big different elemental composition between the urban sludge and coal. For example, the carbon content (20.64%) in the sludge is only 31.3% of the coal. SiO2 in sludge incineration ash contain up to 15%, the same as SiO2 in Siliceous clinker. The sludge ash content (56.46%) is 2 times of in coal ash, anSubscript textd the volatile of sludge (34.6377%)is higher than the volatile of coal (25.089%), the sludge incineration can be divided into three stages: moisture volatilizing stage (30°C to 160°C), devolatilization combustion stage (160°C to 500°C) and fixed carbon and residual combustibles burning stage (510°C to 950°C). The heating rate increased, the volatiles volatilized advance about 50°C. Therefore, the sludge is a high value fuel, which can be used in the burning with coal or building materials.
Effect of Interaction between Earthworm and Microbes on the Degradation Time of Agro-Waste
Authors: Fauziah Shahul Hamid , Emenike Chijioke Uche , Agamuthu Periatamby
Published: March 2013

Impact of macro-organisms in biological processes had been considerably studied but some of the discrete interactions that exist between macro- and micro-organisms still remain complex and sometimes elusive. Agro-waste is a type of waste that remains highly inevitable in our society and its disposal is a subject of concern. Therefore, this study aimed to degrade sugarcane bagasse which is a significant agro-waste in Malaysia, while trying to understand the interaction between microbes and earthworm utilized in the bioprocess. Sugarcane bagasse was blended with spent tea in equal ratio before composting with the aid of Eudrilus eugeniae and introduced microbial consortia. Though varied, pH values across the amendments tended towards alkaline state, just as the available Phosphorus (P) and exchangeable Potassium (K) increased in the value. Total organic carbon (TOC) across the amendments showed reduction in value; 47% in TS (tea and sugarcane bagasse), whereas 25% in TS6M (Tea + sugarcane bagasse + 6 microbes) and 68% in TS3M (tea bagasse + 3 microbes). However, weight loss in Eudrilus eugeinae was found to be proportional to the reduced time of degradation. TS3M at 33% worm weight loss was recorded at 11 day degradation time, than TS6M (27%) and TS (16%) that showed 13 and 20 days degradation time respectively. Weight loss in earthworm is correlated with microbial interaction and can be a reflection of rate decomposition of organic components of agro-waste in a vermicomposting process.
Environmental Chains for Secondary Raw Materials to Reduce Production Wastes through Reuse and Recycle
Authors: Costantino Francesco , Di Gravio Giulio , Sciarra Genny , Tronci Massimo
Published: March 2013

The issue of waste management has been a social and political priority for many years. Different experiences show what benefits can be obtained through interventions that reduce waste or foresee some mechanisms for reusing and recycling. In this context, the paper presents the results of a project financed by the EU LIFE + fund, dedicated to the creation of chains of secondary raw materials. The paper shows the methodology used and the results achieved in the project. In particular the chain for the recovery of olive oil mill wastes is presented. A feasibility study for a recovery facility is performed, confirming the profitability of the proposed technology and the goodness of the design methodology.
Experimental Study on Deformability and Shear Strength of Solidified Dredged Soil
Authors: Jiang Hong Ming , Liu Wen Bai
Published: March 2013

To protect the marine environment, a kind of new composite curing agent was used to solidify dredged soil. The compression test and direct shear test were conducted to make experimental study on solidified soil of 2 curing time and 4 curing agent content, and to analyze the effects made by curing time and curing agent upon soil shear strength and soil compression modulus. The results show the increase of curing time raises compression modulus and soil cohesion to some extent but affects soil internal friction angle slightly. The rise of curing agent content makes a significant growth of compression modulus and cohesion. The compression modulus and cohesion of 7%-curing-agent solidified soil are respectively 1.57 and 15.8 times those of plain soil. But curing agent impacts slightly on the increase of internal friction angle. The maximum growing rate of internal friction angle is just 18.2%.
Remediation of Chromite Ore Processing Residues with Bacteria, Biomass and Ferrous Sulfate
Authors: Wang Tian Gui , Li Ji Sheng , Qin Li Ling
Published: March 2013

Large amounts of chromite ore processing residues (COPR) containing hexavalent chromium (Cr(VI)) discharged from the production processes of sodium chromate and dichromate need to be treated since Cr(VI) has been recognized as a carcinogen internationally and has posed a great threat to the environment and human health. Remediation of COPR containing Cr(VI) with bacteria, biomass and ferrous sulfate was studied in this work. A strain of Cr(VI)-reducing bacteria (CRB), a strain of sulfate-reducing bacteria (SRB), orange peels and ferrous sulfate were used as antidotes to reduce Cr(VI) to Cr(III). The experimental design methodologies — Uniform Design and Orthogonal Experimental Design were adopted to investigate the effects of the reductants on the reduction of the Cr(VI) in COPR. The results show that orange peels and CRB can reduce Cr(VI) in COPR over 95% in 30 days. Together using the four stuff can reduce Cr(VI) over 97% in 12 days. However, it seems that presence of the SRB is not beneficial to Cr(VI) reduction because it might refrains the action of CRB. Therefore, it is not surely beneficial to apply multiple microorganisms simultaneously to the reduction of Cr(VI) in COPR.
The Quantitative Characters of Soil Microbes under Different Vegetations in an Eutrophic Lake Wetland
Authors: Wu Lin Hui , Zhao Ji , Hui Min , Shao Yu Qin
Published: March 2013

There was varying degrees of correlation between the number of soil microbial and soil physicochemical properties, there existed a significant positive correlation (P<0.05) between the number of soil microbial and soil organic matter, total nitrogen; while there existed a significant negative correlation(P<0.01) between the number of soil microbial and pH, which showed that the salinization was the key factor that affected the distribution of soil microbial quantity.The study on variation of the number of soil microbial and soil physicochemical properties of the four kinds of plant community at WuLiangSuHai wetlands, reveals that: Chenopodiacea (Suaeda glauca Bunge) plots, Zygophyllaceae (Nitraria tangutorum Bobr) plots, Artificial Tamarix plots and Artificial Elaeagnus angustifolia plots. The results showed that: 0-20cm of the topsoil, the soil microbial population of them was different, Bacteria, Actinomycete and Fungi on the Artificial tamarix soil was significantly higher than other plant. The number of microbe in Chenopodiacea (Suaeda glauca Bunge)plots soil was the lowest.
Development of Plasma Technology for the Treatment of Environmental Wastes
Authors: Sun Lai Zhi , Yang Li Guo , Chen Tian Ju , Chen Cheng Min , Wang Kai , Ma Yu Qin , Fan Xiao Xu
Published: March 2013

This article summarizes the concept and classification of plasma. The application of plasma technology for the treatment of waste gas, waste water and solid waste are also introduced, and future developments of plasma technology in the field of environmental protection are discussed.
Influence of Water Level on Cynodon dactylon Population in Water-Level-Fluctuating Zone of the Three Gorges Reservoir
Authors: Li Qiang
Published: March 2013

To research influence of water level changes on vegetations restoration in water-level-fluctuating zone of the Three Gorges Reservoir, Cynodon dactylon in Changshou area was respectively investigated in 2008 and 2009. The results show that germination rate in 2009 is 45.3% lower than that in 2008. Total rhizome length and total node number of rhizomes in 2009 significantly increase by 303.5% and 411.1%, respectively. However, stem length, node number, leaf width and leaf number of ramets decrease by 60.1%, 55.1%, 28.6% and 33.8%, respectively. Meanwhile, total buds number, germinated buds number and buds number to rhizome length ratio in 2009 increase by 500.7%, 228.5% and 50.9%, respectively. Compared with 2008, fresh mass of ramats, rhizomes and roots reduce respectively 65.6%, 23.4% and 70.0%, and their dry mass reduce respectively 65.9%, 18.8% and 64.5%. Therefore, water level changes accelerate rhizomes extension and the formation of buds and ramets, and inhibite ramets growth.
Elastic-Plastic Finite Element Analysis on the Spillway of a Concrete Gravity Dam
Authors: Cao Liang , Wang Hui Min , Yao Ji , Qian Shan Guang , Tang Chun Feng
Published: March 2013

The 3-D finite element model of a concrete gravity dam’s spillway was established in this paper, and the elastic-plastic theory was applied, then the deformation and stress state of the dam under various working conditions were analyzed, it was prooved that the deformation and stress state of the dam were in normal condition. After solving the force of the dam foundation surface and taking full account of the complex geological conditions, the dam’s sliding stability was analyzed by capacity limit state design formula. The calculation results showed that, the stability parameter of the dam along foundation surface was bigger than 1.0, the dam’s sliding stability met the requirement.
Research on Main Problems and their Countermeasures on Chinese Small Hydropower Development
Authors: Zhai Yan Wei , Liu Chang Wu , Zhai Xina Xian
Published: March 2013

The constructions of small hydropower stations play an important role in improving local energy structure, development of corporations, agricultural and environmental melioration, and improving living standard of local people. Thus, studying status at small hydropower stations of China and existed problems in their development has a practical significance. With investigation data, the paper comprehensively analyzed running status of the stations, equipment aging in their development, lower utilized water resources, backward management, and disordered exploitation, etc. Therefore, the authors put forward the stations need to be technically reformed, perfecting management, professional training and so on, so that utilization efficiency on water resources could be continually improved.
The Wavelet Analysis of Diverted Water from the Yellow River in Donglei Irrigation District
Authors: Zhang Li , Su Xiao Hui , Yin Jun , Guo Fei , Lin Wen Bo , Zhao Ru
Published: March 2013

Based on the long term diverted water volume data of 1980-2007 in Donglei Irrigation District, multi- scale and trend characteristics of the diverted water are revealed by using wavelet theory. The results showed that diverted water volume changes at different scales of 12a, 7a and 2a; annual diverted water volume generally appears a tendency of increasing;analysis of some impact factors of diverted water by tendency analysis revealed that precipitation and the planting areas for corn have great influence on water diversion.
The Influence of Hydrodynamic Conditions on Algal Bloom in the Three Gorges Reservoir Tributaries
Authors: Xiong Chao Jun , Liu De Fu , Zheng Bing Hui , Zhang Jia Lei , Hu Nian San , Zhang Yu , Chen Yang
Published: March 2013

Water level has risen considerably since the impounding of Three-Gorges Reservoir in year 2003 and that might broaden and deepen the Yangtze River and the tributary of Three Gorge, will greatly slowdown the flow velocity to change hydrodynamic conditions. This changes Influence the Water Environment of Yangtze River and the tributary of Three Gorges Reservoir, especially eutrophication and algal bloom of the tributaries in Three Gorges Reservoir in recent years. For studying the course of algal bloom in the tributaries of Three Gorges Reservoir and the comprehensive prevention countermeasures, about the hydrodynamics of Yangtze River main stream and tributary in Three Gorges Reservoir must be carefully researched. In this article, general situation of the algal bloom of the tributaries in Three Gorges Reservoir were presented, and analysed on characteristics and influencing factors of breakout of algal bloom from certain self-conditions changes before and after impoundment of the Three Gorges reservoir, knowing that lower the nutrient input and improve water flow regime and flow velocity behaviors are the main measures of comprehensive prevention countermeasures of algal bloom in the tributaries of Three Gorges Reservoir; This research status of influence mechanism of hydrodynamic conditions on algal bloom and the research tendency of the tributaries’ hydrodynamic conditions on algal bloom in Three Gorges Reservoir were reviewed, which provided certain theory reference for study and prevention countermeasures of algal bloom in the Three Gorges Reservoir tributaries.
Engine Fault Diagnosis Using Acoustic Signals
Authors: Adaileh Wail M.
Published: March 2013

This work presents an experimental study to detecting the faults of engine using its noise. The noises produced by the engine and its accessory systems are numerous: whines, squeals, knock, rattles, and many other sounds. Faults diagnosis for Mitsubishis car engine model 2006 has been conducted and this diagnosis includes normal operating conditions for the engine (without malfunction) and for malfunctions situations at variable engine speed 1000,2000, 3000 and 4000 rpm respectively The engine data is acquired from a four cylinder one- petrol engine test bed under consideration at different operating states, and then simulated. Most of the conventional fault diagnosis techniques using sound emission and vibration signals are based on analyzing the signal amplitude in the time or frequency domain. For engine under fired and misfires spark the all the domain parameters (RMS amplitude, peak amplitude and energy) was processed using MATLAB software.It was found that fault detection and diagnosis for internal combustion engines is complicated by the presence of engine noise during normal operation. The average of amplitude found to be 450 x10-3m for normal engine working without any malfunction and 458x10-3m for misfire of one spark plug and for misfire of two spark plugs 457.8 x10-3m. In this study, some of the engine malfunction such as failure spark plug has been recorded, but we can generalize it to include all engine breakdown. Generally, sound emission signal serves as a promising alternative to the condition monitoring and fault diagnosis in rotating machinery when the vibration signal is not available. This research paper explores that automobiles could be major sources of noise pollution. Condition monitoring and fault diagnosis of IC engine through acoustic signal analysis is an established technique for detecting early stages of component degradation.
Vibration Propagation Law and Control Test of Ultra Soft Soil Ground under Impact Load
Authors: Li Zhang Ming , Zeng Wen Xiu
Published: March 2013

Through in situ tests on the impact vibration of a typical muck ground treatment major project directed by the first author, the vibration propagation law under the impact load for the ultra soft soil ground is obtained, and quantitative environmental safe control distance on the vibration influence is also gained. The main results are the two aspects. (1) The attenuation law of both level and vertical peak vibration acceleration with the horizontal distance can be described well by the negative power function; and the ground vibrations caused by tamping impact can be distinguished between two types, i.e. near-field and far-field. Near-field tamping vibration influence is confined to a small range of the tamping center, which decays obviously faster than the one of far-field. (2) The radius of influence of tamping vibration depends not only on the tamping energy but also the soil type. Loose, slightly dense soft soil has a larger energy absorption capacity and a smaller effect radius of tamping vibration than the dense and hard soil; and the vibration safe control distance is determined as 27.3m in the tests according to the safe boundary determined code of industrial and civil architecture in China.
The Theoretical Study of Noise Control Engineering Design
Authors: Xu Nan , Zhang Chi
Published: March 2013

Mine ventilation system is serious pollution to the surrounding environment. Due to the air flow rate, high speed, strong noise radiation. In addition to the scientific and reasonable design for muffler, ventilation resistance loss calculation is one of the key successful factors of project design, in order to eliminate the noise pollution of mine ventilation system.In recent years,people's awareness level of the harm of noise rises ceaselessly, the environmental protection departments also gradually enlarges the management and punishment to noise pollution.The noise control of coal mine ventilation system with strong radiation and harm has become a pressing matter of the moment. Because the theory calculation of noise control design is fuzzy, Some environmental protection company implement noise control by virtue of experience or imitation of other engineering, leading to a series of problems, such as noise control can not reach the design standard, large ventilation resistance, energy consumption increased, regeneration noise exceed the standard, system vibration. Based on the systematic study for engineering design, i summed up the theory calculation rule for the coal mine ventilation system noise control, as reference to technical personnel.
The Role of Air Damping in Synthesized Damping of Litchi Tree Vibration
Authors: Liu Tian Hu , Luo Yu Xiang
Published: March 2013

In order to analyze the role of air damping in synthesized damping of litchi tree vibration, the fruit tree was simplified into a cantilever firstly. Then, according to equations of equivalent stiffness, equivalent damping, and equivalent mass, the damping ratio of air resistance was analyzed. The results showed that such damping ratio increases with the height of canopy center and the canopy size, and decreases with canopy mass and trunk radius. Within normal trunk radius, trunk length, canopy size, and canopy mass range, the damping ratio of air resistance is much smaller than 1.
The Impact of Different Grazing Intensity on Topsoil Physical and Chemical Properties in Xilamuren Grassland
Authors: Fang Yi , Li Xiao Jia , Chen Cong Cong , Zhang Min , Zhou Rui Ping , Gao Tian Ming , Zhang Rui Qiang , Hai Chun Xing
Published: March 2013

Grassland is an important ecosystem in land surface. Soil is the basis of grassland ecosystem, and the changes of its properties directly affect grassland ecosystem. The study region is located in Xilamuren grassland using the methods of field sampling and experimental analysis. It was divided into four test areas according to grazing intensity. Soil physical and chemical properties were analyzed in each test area. The results showed that: the trend of soil water content decreased and then increased with increasing grazing intensity, soil water content in repaired grassland was the lowest. For the soil mechanical composition, particle size content increased first and then decreased with increasing grazing intensity when the particle size was 1-0.05mm. The difference between the highest and lowest values was obvious. When the particle size was 0.05-0.002mm, the trend of particle size fluctuated, first decreased and then increased, finally reduce again and the difference between the highest and lowest values was obvious. When the particle size was less than 0.002mm, the trend of particle size content increased with increasing grazing intensity. In soil chemical properties, soil organic matter appears downward trend overall as grazing intensity increase. Soil organic matter content was the lowest in repaired grass. Available N and P first decreased and then increased with increasing grazing intensity, the minimum values appeared in the repaired grassland and degraded grassland respectively. Available K content increased with increasing grazing intensity.
Current Situation and Prospect of Microbial Residual Oil Gasification
Authors: Xing Dong , Li Yong Feng , Wei Li , Zhang Jing Wei
Published: March 2013

Most Oilfield of China has been a stage of Oil recovery with high water, microbial residual oil gasification technology as the oilfield's reserves technology has a good application prospect, especially the use of microorganisms for gasification of residual oil. The study has far-reaching significance, and it mainly turns the difficult mining oil reservoir into natural gas (mainly methane) through microbial degradation. It is the most effective, economical and environment-friendly way to enhance oil recovery efficiency and to extend the reservoir life. This paper summarized the relevant principles of oil microbial degradation and gasification, microbial enhanced oil recovery and Residual oil gasification at home and abroad, and come up with a few new research ideas.
Prediction and Prevention of Water and Soil Erosionin Qilinsi Hydro-Electric Power Station Project Construction
Authors: Ren Jian Min , Ran Xin Min , Jiang Cun Ren
Published: March 2013

Qilinsi hydro-electric power station is constructed for power generation. This paper analyses the influences of seven aspects to water and soil erosion in project constructing, such as construction occupation land, dig and backfill of main body, project discard- dregs, materials field exploitation, construction traffic roads, immigrants installing and geologic disaster. The water and soil erosion quantity was predicted. Prevention measures for water and soil erosion were presented correspondingly and it has important significance for constructing the project successfully and improving circumjacent environment.
Environmental Problems and Control Ways of Plastic Film in Agricultural Production
Authors: Zeng Lu Sheng , Zhou Zhen Feng , Shi Yan Xi
Published: March 2013

People use plastic film mulching to increase soil temperature, keep water and protect crops from insects and grass, therefore, which increased crop yield. However, with the film used years increasing, a lot of film residuals accumulated in the field. As a result, the increasing residuals destroyed soil structure, affected agricultural environment, harmed the crop growth, and furthermore, affected the food safety and human health. So, government should strengthen environmental publicity to improve the understanding of the film pollution, work out the residual film management laws and regulations, develop the recycling economy to reuse the residuals, and research biodegradable films and other ways to prevent agricultural environment from pollution.
The Analysis of the Necessity and Feasibility of Carbon Dioxide Storage in China
Authors: Huo Chuan Lin , Huo Cheng , Guan Dao Ming
Published: March 2013

Carbon capture and storage (CCS) is a significant strategic climate protection technology, and has become the most possibility and practical significance approach of emission reduction. CCS technology is the means to reduce the amount of CO2 into the atmosphere in the case of no reducing the amount of fossil fuels. China's CO2 emissions are the second in the world and it is difficult to change the current energy consumption in a short time. CO2 emissions will continue to increase with the rapid development of China's economy which will bring the huge CO2 emission reduction pressure. In this paper the CCS technology is introduced and the necessity and feasibility of CCS in China are analysed.