bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Operation of Underground Reservoir in Tailan River Basin
Authors: Jing Yan Dong , Shu Long Cang , Deng Ming Jiang , Appiah-Adjei Emmanuel Kwame , Zhang Shuai Ling , Wang Xiao Hui , He Ping
Published: October 2012

Tailan river basin is a typical drought river basin in northwest China where construction of underground reservoirs is approved as an effective way to solve the problem of water resource shortage in the river basin. In order to ensure water supply efficiency of the underground reservoirs of the basin, it is necessary to research their recharge and supply patterns and to optimally operate them. This paper has, therefore, investigated different recharge locations and recharge ways through numerical simulation of underground flow in an underground reservoir area of the basin to explore a typical scheduling plan for optimal operation of the reservoir. The results show that it is better to recharge the reservoir using the flood season recharge approach at the centre of the reservoir area to ensure its continuous operation. Following from this recharge process, the use of a three-well pumping scheme is regarded as the best choice for optimal water supply from the reservoir. Also, the study indicates that for the same recharge amount, if the recharge time is closer to the pumping peak, then there is the more obvious effect of underground level recovery; the recovery is much better if the recharge time is more concentrated.
3-D FEM Analysis of Large-Scale Prestressed Concrete Aqueduct in the Middle Route of South-to-North Water Diversion Project
Authors: Zheng Chong Yang , Peng Hui , Li Nan Hui , Kang Ya Ting
Published: October 2012

Taking the properties of aqueduct in the middle line of the South-North Water Diversion Project, such as high flow, long span, large load and cross section and so on, two schemes about layout of prestressed steel strands are put forward. In order to guarantee safety of the project and structural optimization, 3-D FEM is adopted to study the regularity of distribution of stress and strain on control section under each condition of the two schemes. The results show that the design of steel strands in the first scheme (wavy steel strands) is much more reasonable and meets the requirements for anti-crack and deflection of the aqueduct body.
Study on Thermal Stress and Temperature Cracks Control of Longlin Roller Compacted Concrete Gravity Dam
Authors: Zheng Wen Yi , Pan Peng , Ye Lie Ping
Published: October 2012

In order to guide temperature control design and construction and to guarantee the construction quality of roller compacted concrete (RCC) gravity dams in severe cold area, it is of great significance to carry out the simulation analysis of temperature and stress. The whole progress of construction and operation of Longlin RCC gravity dam in harsh climate region were simulated by using the heat of hydration analysis control function, construction stag analysis control function and the time-dependent material link of MIDAS.civil.2006. According to the construction process, the curves of temperature and the curves of stress were obtained. The locations where the crack ratio may exceed 20 were also obtained and the correct temperature control measures and the rational construction progress control system were pointed out.
Cracking Analysis of Spiral Case Structure with Combinatorial Embedding Manner of Large Underground Power Station Turbine Unit
Authors: Chen Qin , Qi Yong Feng , Gong Ya Qi
Published: October 2012

The spiral case with combinatorial embedding manner is a novel design and inherits the advantage of the general types of embedding manners of embedded with cushion layers and embedded directly, which is progressively used in hydro projects. In the present paper, the mechanical behavior of a larger spiral case with combinatorial embedding manner is analyzed by using 3-D non-linear finite element method. The deformation of the spiral case structure and crack analysis of outer reinforced concrete structure are carried out. The strengthening measures under the engineering control criterion are also discussed. The results show that the penetrating crack will appear in the concrete and the relative rising displacement of generator pedestal structure is out of the control criterion if no strengthening measures implemented. Increasing the quantity of reinforcement only is not able to hold back the penetrating cracks. The enhancement of the tensile strength of concrete is an effective way to decrease the range of crack propagation, resist the penetrating and decrease the rising displacement of generator pedestal structure. It also indicated that extending the laying length of cushion is another effective way to decrease the rising displacement of generator pedestal structure
Study on the Vertical Displacement Models with Impoundment Factors for a High CFRD
Authors: Zuo Heng Zhong , Zhao Chun
Published: October 2012

Some high CFRDs had the problems of face slab crack and large leakage. And it was found out after deep analysis that the basic reason was the big inhomogeneous deformation in the rock-fill zone, mainly the vertical displacement. So it was of great significance to master their deformation behaviors so as not only to monitor the dam safety but also to supply the suggestions to repair the defect and reinforce the dam. The special features of dam displacement in the initial impounding period should be considered in the quantitative analysis of dam displacement study. Taking a certain dam as an example, some displacement models with impoundment factors were adopted to study the deformation features of high CFRD in this paper. After comparing and testing, the models were verified and could be used to monitor and forecast the deformation of the certain dam.
Temperature Measurement and Data Analysis of the Roller Compected Concrete Dam
Authors: Xing Zhen Xian , Ni Lei , Ma Rong Jia
Published: October 2012

Prototype observation of the concrete dam is an important and effective measure to master the operating condition of dams. Analysis of changes of concrete temperature for dams is the basis of studying the safety of dam operation. By analyzing the raw monitoring data of temperature of a RCC dam, this paper researches the changing process of concrete temperature and internal concrete partitions temperature variation of dams. It also draws the temperature field of the dam concrete. The results show that the isothermals of downstream side parallel with the surface of the downstream dam, and the isothermals of upstream side intersect with the dam. Isothermals which are near to the dam’s surface are close. This suggests that temperature gradient there is large. There is a high temperature nucleus and two low temperature nucleuses in the temperature field of the dam in summer, while in winter there is only one high temperature nucleus. So it suggests that the temperature field in summer is more complex.
Grid Based Change Trend of Precipitation and its Regional Difference in China over the Past 40 Years
Authors: Liao Shun Bao , Zhao Hong Wei
Published: October 2012

First, the software ANUSPLIN4.3 was used to process 40-year observed precipitation data from 680 meteorological stations of China to generate grid precipitation data sets at resolution of 1km by 1km. Second, one-dimensional linear regression method and ArcGIS software were applied to analyze trend of precipitation change and its regional difference in China over the past 40 years. The results showed that general trend of precipitation change in nation-wide was not obvious but its regional difference clear. Precipitation in southeast coast areas rose obviously with a maximum of 5 millimeters per year, dropped in central areas including Circum-Bohai-Sea region, Shanxi, Shaanxi and south of Gansu. There was no obvious change trend of precipitation in the rest areas of China.
Estimation of Excavation Disturbed Zone of High Slope in the Left Bank of Jinping-I Hydropower Station
Authors: Peng Jun , Rong Guan , Li Zhi Lin
Published: October 2012

The proposed Jinping-I hydropower station is located on the middle reach of the Yalongjiang River, Sichuan Province, P.R. China. It consists of a double-curvature arch dam with a maximum height of 305 m, which will be the highest in the world. Excavation disturbed zone (EDZ) in the left bank slope is one of the most important aspects in slope stability and deformation evaluation. This paper is focused on estimation of EDZ in the left bank slope of Jinping-I hydropower station based on numerical simulation. Geological conditions of the left bank slope are firstly analyzed. Then, displacement field of the slope during excavation is calculated by finite element method (FEM). It can be indicated that the model and parameters in this paper is reasonable by comparing observed results with calculated ones. EDZ in the left bank slope can be estimated based on the calculated displacement field. It can be inferred that the range of EDZ is related to the controlling discontinuities such as fault f42-9 and Lamprophyre X etc. which are adjacent to the excavation line.
Green Synthesis of Poly(ρ-Dioxanone)-Modified Cellulose by Lipase-Catalyzed Ring-Opening Polymerization in Ionic Liquid
Authors: Zhu Jiang , Wang Xiu Li
Published: October 2012

A new cellulose graft copolymer was synthesized by the lipase-catalyzed ring-opening polymerization of ρ-dioxanone (PDO) onto cellulose in 1-N-butyl-3-methylimidazolium chloride ([Bmim]Cl). The structure of the copolymer was characterized by FT-IR and 1H-NMR. The obtained copolymers exhibited the different thermal stability by TGA after the graft copolymerization. The reaction media applied can be easily recycled and reused.
Effect of Cold-Rolling Reduction on Recrystallized Annealing Microstructure and Texture of Titanium Stabilized Interstitial Free Steel
Authors: Zhang Gong Ting , Zheng Zhi Wang , Wang Min Li
Published: October 2012

Cold rolling and salt bath annealing simulation were conducted to study the evolution of microstructure and textures of a commercially produced Titanium stabilized interstitial free steel by means of optical microscopy and X-ray texture measurement. The results show that all of the as cold-rolled specimens are completely recrystallized after annealing. As the cold-rolling reduction increases, the recystallized ferrite grains are refined, The intensities of the stable {114} and {223} components remain strong after recrystallization. The orientation intensity of the {111} and {111} also increases accordingly. As the cold-rolling reduction increases to 90%, the intensity of {111} tend to be higher than that of {111}.
Effect of FeO on Sintering and Leaching of Calcium Aluminates in the CaO-Al2O3-SiO2 System
Authors: Pan Xiao Lin , Yu Hai Yan , Dong Kai Wei , Wang Bo , Zhang Wu , Bi Shi Wen
Published: October 2012

The sintering characteristic and leaching property of calcium aluminates in the CaO-Al2O3-SiO2 system with different FeO additions were investigated. FeO decreases the melting temperature of clinker, and makes the clinker not self-pulverizable. As FeO addition increases from 0 to 4%, the main phases of clinkers sintering at 1350 °C are 12CaO•7Al2O3 and 2CaO•SiO2 as well as some CaO•Al2O3 when the mass ratio of Al2O3 to SiO2 is 5.0 and the molar ratio of CaO to Al2O3 is 1.4. The interplanar spacing of 12CaO•7Al2O3 in the clinker increases with the increase of FeO addition, and the proportion of CaO•Al2O3 in the clinker decreases with the increase of FeO addition. FeO does not affect the Al2O3 leaching rate of clinker obviously, but increases the molar ratio of caustic Na2O to Al2O3 in the leached liquor.
Effect of Strain Rate on Mechanical Properties of Fe-30Mn-3Si-4Al TWIP Steel
Authors: Xiong Zhi Ping , Gu Lei Gang , Wang Ye Ke , Zhao Ji Cheng , Bao Wei Ping , Ren Xue Ping
Published: October 2012

Influence of strain rate on mechanical properties of Fe-30Mn-3Si-4Al TWIP steel was studied by compression experiments, indicating that TWIP steel has strain rate softening effect, strain rate insensitivity, and also strain rate hardening effect. According to strain rate sensitivity m changing with strain rate, effect of strain rate on TWIP steel mechanical properties can be divided into three stages: quasi-static stage with strain rate ranging from 0.001 to 100 1/s; high-strain rate stage with strain rate ranging from 701 to 5108 1/s; super-high-strain rate stage with strain rate ranging from 10335 to 30147 1/s. Adiabatic temperature rise tends to increase with strain rate. Strain hardening exponent is divided into three parts: dislocation strengthening stage, twinning strengthening stage and thermal softening stage.
Effect of Tempering Process on Structure and Properties of Super Martensitic Stainless Steel
Authors: Sun Hu Dai , Zhao Kun Yu , Rui Jia Qun , Jiang Wen , Han Xiao Chen , Yong Qi Long , Su Jie
Published: October 2012

Two types of super martensitic stainless steels (Cr13 and Cr15) were designed. The effect of tempering process on their microstructure, mechanical properties and corrosion resistance was studied. The results showed that the main microstructure of tested steels was tempered martensite and a small number of reversed austenite when specimens were tempered in temperature range of 550-750°C. The variation of mechanical properties corresponded to the austenite volume fraction well. Both the two types of steels displayed a favorable comprehensive mechanical properties after tempering at 650°C, their product of strength and elongation reached to 18.44GPa•% and 18.44 GPa•% respectively. With the best heat treatment process,tempered at 650°C after quenching at 1050°C,the corrosion resistance of 2# steel is more better than 1# steel.
Effects of Particle Size of Coke on the Electrical Property and Hardness of Copper/Coke/Phenolic Resin Composites
Authors: Li Mi Dan , Yang Hong , Niu Huan , Zhang Chun Mei , Lu Yao
Published: October 2012

Composites made from phenolic resin are filled with conductive filler mixtures containing coke powder and copper powder. They are fabricated by compression molding, followed by post-curing method. The density, electrical conductivity and hardness of composite are analyzed to determine the influence of coke particle size on the physical, electrical and mechanical properties of composite. It is found that there is a marked dependence of the density, electrical conductivity and hardness on coke particle size. The density and hardness decrease with the increasing of coke particle size. However the electrical conductivity increases with the increasing of coke particle size. The increasing of coke particle size from 0-48 µm to 75-180 µm promotes a considerable increase in electrical conductivity by about 204%. The intra-particle conductivity and connectivity of copper particle could be the main reasons for the increasing of electrical conductivity as coke particle size increases.
Finite Element Simulation of Nickel-Plated Steel Sheet in Stamping Process
Authors: Tan Zan Wu , Xu Kong Lian , Hu Su Yun
Published: October 2012

Nickel-plated steel sheet with high ductility and wonderful corrosion resistance, it has been widely used in industry. Stamp forming is a high-volume fabrication method for producing desired components. To determine the optimum values of the process parameters, it is essential to find their influence on the deformation behaviors of the steel and nickel. In this paper, finite element method (FEM) simulation was carried out to analyze some factors such as stress distribution, strain distribution, and fillet radius.
Influence of pH on the Electrochemical Bahavior of 00Cr15Ni7Mo2Cu2 Supermartensitic Stainless Steel in 3.5% NaCl Solutions
Authors: Rui Jia Qun , Li Jun , Sun Hu Dai , Zhao Kun Yu , Li Zhi Dong , Han Xiao Chen , Yong Qi Long , Su Jie
Published: October 2012

This objective is to study the influence of pH on the electrochemical behavior of 00Cr15Ni7Mo2Cu2 supermartensitic stainless steel in 3.5% NaCl solutions using potentiondynamic polarization technique, open circuit potential tests and electrochemical impedance spectroscopy (EIS).The study reveals that the pitting potential (Eb) is higher, the passivation current densities (ip) is lower and the electrochemical impedance increases with the pH. The results indicate that this stainless steel offer good pitting corrosion resistance with the pH increasing in 3.5% NaCl solutions.
The Study of Color Film Phosphating Process in Steel before Coating
Authors: Chen Ze Min , Wu Zhi Li , Zhang Qiao Yun
Published: October 2012

This study through a lot of theoretical analysis and experimental exploration, come to add phytic acid and chromium alum in the traditional zinc phosphating solution for phosphating solution film-forming speed and improve the film density has a distinct effect, and further by orthogonal experiments and the final assessment of preferred a group of environmental, low-temperature, and no sediment of new phosphating process. The composition of the phosphating solution is as follow: zinc oxide 0.5g/L; phosphating acid 5.0mL/L; tartaric acid 0.75g/L; sodium molybdate 0.6g/L; Ma Jif salt 2.0g/L; NaF 0.25g/L; phytic acid 0.4mL/L; chromium alum 1.0g/L; free acidity 2-4 points; total acidity 15-18 points. The experimental results show that: the new phosphating process of this study reduces the handling costs, the stability bath performance, little changes in acidity, in the case of do not need to adjust the surface at room temperature, to forming a completed, dense, strong corrosion-resistant color phosphate crystal film on metal surface within 5 minutes, the copper sulfate bit time is 2.5mins, with good adhesion to 0, the impact resistance is 50kg/cm, it can be used in conjunction with a variety of coating processes.
Application of the Enzymolysis and Membrane Technology in Glucan Extraction and Purification from Grifola frondosa
Authors: Zhou Chuan Bing , Xu Ze Ping , Feng Wen Juan , Zhang Xin Qing
Published: October 2012

It has been investigated that the application of the enzymolysis and membrane technology in the extraction and purification of glucan from Grifola frondosa. The fruitbody of Grifola frondosa was been used to extract polysaccharides. Compared the yield, protein content and polysaccharide content in the extracts under 3 different process modes, it was found that the procedure processed by complex enzyme was better than the others. Microfiltrated with membrane of 0.2μm aperture and then ultrafiltrated with membrane with molecular weight cutoff of 1000 Dalton, it had glucan retained rate of 80.42% and protein removed rate of 88.27%. GCP experiment indicated that the glucan get from the procedure was a homogeneous polysaccharide with weight average molecular weight of 130355 Dalton. The index of molecular weight distribution was 1.1844. The desalination rate was increased by adding water to the concentrate while ultrafiltration was in progress. When the quantity of water added was 1.5 times of the concentrate volume, it had effective desalination effect with the ash content of 3.79% in final product.
An Electrochemical Corrosion Study of SAE1045 Steel in SiO2 Gel with 3 wt% Sodium Chloride
Authors: Lu Nan , Yao Yi , Gu Kun Ming , Lu Zhao Long , Yang Hai Peng , Tang Jiao Ning
Published: October 2012

To get basic information on corrosion of metals under sewage sludge environment, in this work, the corrosion behavior of SAE1045 steel under SiO2 gel with 3 wt% NaCl was investigated by electrochemical polarization method. The results show that the self-orrosion potential of the steel move to more negative value in SiO2 gel comparing to those in aqueous solution. It was found by SEM and EDX measurements that, after 15 days of wilhelmy test in SiO2 gel, a dense covering layer containing a lot of Si appeared on the surface of steel, which was attributed to the difference of corrosion behavior for the metal under SiO2 gel and aqueous solution.
The Effects of Nd on Lead Anode for Zinc Electrowinning
Authors: Zhong Xiao Cong , Hong Bo , Li Yan Hong , Jiang Liang Xing , Lai Yan Qing
Published: October 2012

A detailed investigation of the effects of Nd on the microstructure, mechanical properties and electrochemical properties of lead anode in 160g.L-1 at 35°C was carried out. Galvanostatic polarization and Chronopotentiometry (CP) were used to study the electrochemical behavior ( such as anodic potential, corrosion rate and the composition of passive film) of the Pb and Pb-Nd anodes. The metallographic structure and passive film morphology of Pb and Pb-Nd anodes were observed and analyzed using polarizing microscope and scanning electronic microscopy (SEM), respectively. The experimental results show the grains become smaller and aggregation of PbxNdy become severe as the content of Nd increases. The addition of Nd enhances the formation of PbO2, inhibits the formation of PbSO4 and PbO and reduces the anodic potential. However, Holes presenting on rough passive film of high Nd content Pb-Nd anodes accelerate the corrosion.
Kinetics on the Isothermal Decomposition of Oil Shale
Authors: Xue Hua Qing , Wang Hong Yan , Yan Gang , Guo Wei , Li Xiao Bo , Wang Hong Chao
Published: October 2012

The kinetics of the thermal decomposition of Huadian oil shale was studied at five different isothermal atmospheres of 623K, 648K, 673K, 698K, and 723K. The temperature recorded was that of the sample that the temperature error between furnace and sample will eliminate. According to conversion data, the effect of increased temperature is to decrease the pyrolysis time. The conversion data described the oil shale pyrolysis as two stages, rapid conversion and modest conversion. The Arrhenius equations of ki=1.40×105e-109828/RT and kii=1.76×106e-130463/RT were obtain by isothermal kinetics model for each stage.
Spectrophotometric Determination of Kryptofix 2.2.2 Using TCNQ
Authors: He Mu Yi , Sun Li Quan , Luo Ai Qin
Published: October 2012

The interactions of the electron donors kryptofix (K-222) with 7,7,8,8-Tetracyanoquino- dimethane (TCNQ) were studied spectrophotometrically in aceton/water at several temperatures. The UV-vis spectra of the formed molecular charge transfer (CT) complexes were recorded. The molecular structures of the CT-complexes were independent of the position of the amino group on the K-222 and were formulated as [(K-222)(TCNQ)]. A spectrophotometric method for determination of K-222 was developed and validated for the quantitative analysis of K-222 in the radiopharmaceuticals. With an internal standard, the limit of quantitation for K-222 was 2 ug/ml. This is so far the most facile method for the determination of K-222. Excellent linearity (RSQ = 0.9997) was obtained over the range of 2.0–31 ug/ml. Good precision and accuracy were also observed. The method is amenable to the validation of radiosynthetic methods.
Exploration of Exhaust Gas of Natural Gas Catalytic Combustion in the Aseptic Box
Authors: Yan Long Fei , Xiao Min , Zhang Shi Hong
Published: October 2012

Because exhaust gas of the natural gas catalytic combustion is clean and sterile, the exhaust gas can be used in aseptic boxes, high-temperature exhaust gas pre-sterilization of the aseptic box, the continuous low temperature flue gas pass into the sterile containers, aseptic containers in during use to maintain a clean and sterile, and has greatly improved the device and working environment of the sterile boxes.
Perspectives on Physicochemical Properties and Application of Biodiesel Blends
Authors: Zhao Yan Hui , Zhang Jia Xi
Published: October 2012

This paper analyzes a series of physicochemical properties of biodiesel blends, then explores the effect of biodiesel content on physicochemical properties of the blended fuel and the application prospects of biodiesel.
Preparation and Application of the Amino Silicone Oil / Acrylic Emulsion
Authors: Tan Yan Jun , Liu Chang Nan , Chen Xiu Na
Published: October 2012

To solve the problem of pigment printing’s hard handle and poor fastness, we have synthesized an amino silicone oil / acrylic emulsion blending adhesive to improve the printing handle and fastness in the paper. We studied the synthetic monomers and influencing factors to explore the best synthesis process of the acrylic emulsion polymerization. The synthetic acrylic emulsion and amino silicone were blended to explore the best printing process. We find that the printed fabrics have a good handle and significantly better rubbing fastness.
Preparation of Biodiesel from Crude Rubber Seed Oil by Alkaline Transesterification
Authors: Wang Hong , Sun Yan Lin , Zhang Li
Published: October 2012

Abstract: This paper is focused on the preparation of biodiesel from crude rubber seed oil with high free fatty acids (FFA) content. The rubber seeds were collected in Xishuangbanna, Yunnan province. Two-step synthesis was selected to obtain the product, that is, acid catalyzed esterification was carried out first to decrease the FFA content, then methyl esters of fatty acids can be formed by alkaline transesterification. The reaction conditions of alkaline transesterification were investigated. The results show that the optimum technique is to carry out the reaction at 60°C for 1.5h, with the methanol-to-oil molar ratio 6:1, the catalyst amount 1.0% (g NaOH/ g oil). The yield can reach 75%. GC analysis shows the content of methyl esters of fatty acids is 82.29%. Some properties of biodiesel prepared are also presented.
Research on the Utilization and Industry Development Strategies of Fluorite Resources in China's Fluorine Chemical Industry
Authors: CHEN Shi Yi , Zhang Shou Ting
Published: October 2012

This paper introduced fluorite resource profiles on the basis of elaborated China fluorite resource utilization status, focusing on analysis of fluorite in the fluorine chemical industry, discusses the problems of our country in the fluorine chemical industry development and firefly stone rational use of resources and the sustainable development of China's fluorine chemical industry recommendations.
Chemical Composition of the Essential Oil of Fresh Wild Syringa pubescens Flowers from China
Authors: Yu Ai Nong , Yang Xing Zhi
Published: October 2012

The essential oil of fresh wild Syringa pubescens flowers from China was obtained by hydrodistillation and identified by GC–MS. Altogether 49 components, mostly terpenoids and benzene derivatives, were identified. Many compounds are responsible for flowery or flowery-like aroma, such as benzyl alcohol, benzene acetaldehyde, cis-linalool oxide (furan), linalool, phenylethyl alcohol, α-terpineol, myrtenol, cis-geraniol, p-vinylguaiacol, eugenol, trans-nerolidol, etc. The predominant volatile compound in fresh wild Syringa pubescens flowers was furfural, followed by phenylethyl alcohol, carveol, borneol, eugenol, linalool, 2-propenylbenzoate, camphor, 4-terpineol, α-terpineol, benzaldehyde, trans-nerolidol, α-cadinol, thujone and benzyl alcohol. These results suggest that essential oil of fresh wild Syringa pubescens flowers has important flowery or flowery-like aroma properties and may be useful as a natural flavor to replace synthetic flavor.
Simultaneous Determination of Hydrochlorothiazide and Propranolol Hydrochloride in Powder Mixture and Matrix Tablet Using First Derivative Ultraviolet Spectrophotoscopy
Authors: Choncheewa Chai Ek , Phaechamud Thawatchai
Published: October 2012

Normal UV-spectrophotoscopy [D0] cannot determine the combined drug in the formulation due to overlapping of the absorbance of each compound hence the derivative UV-spectrophotoscopy is used to determine the combined drug simultaneously. For determination of both hydrochlorothiazide [HCT] and propranolol hydrochloride [Pro] in powder mixture and matrix tablet, the first order derivative UV-spectrophotoscopy [D1] was employed in this study. This method showed good accuracy and precision for simultaneous determination of both drugs. Recovery was 106.59% and 97.11% for Pro and HCT, respectively. Reproducibility of both drugs was found to be less than 2.5% RSD. Repeatability was less than 2.0% of both drugs. Limit of detection (LOD) was 0.10 and 0.49 μg/ml, respectively. Limit of quantification (LOQ) was 0.31 and 1.48 μg/ml, respectively. The drug dissolution was conducted either powder mix or matrix tablet prepared by molding technique. Both drugs in powder mixture showed faster release than that from the matrix tablets. As the results, the first derivative UV-spectrophotoscopy could separate the overlapped spectra of HCT and Pro either in powder mix or in matrix tablet hence it could be used to determine the mixture of these two drugs in dosage forms.
Study on Processing of Plantation Fir Scrap Liquefaction by Ionic Liquids
Authors: Xie Hong Lu , Wu Yan Ling , Huang Jian Hua , Zheng Lin Lu
Published: October 2012

Liquefactions have been carried out on plantation fir scrap, with allylimidazolium ionic liquids as liquefaction agent. The primary component of plantation fir was analyzed, fir scrap properties were tested in contrast to peeled fir. Single-factor experiments were employed to discuss the influential factors liquefying plantation fir scrap by ionic liquids. The results showed that the appropriate conditions of liquefaction were 80°C, 30min, and the ratio of wood to liquor was 7:1, in these conditions, the liquefaction is nearly complete.
Supramolecular Assembly of Functional Cholesteryl Substituted Luminol Derivative in Organized Molecular Films
Authors: Zhou Jing Xin , Jiao Ti Feng , Li Adan , Xing Yuan Yuan
Published: October 2012

Functional luminol derivative with cholesteryl substituted group has been designed and synthesized from the reaction of the corresponding precursor cholesteryl chloroformate with luminol. This compound can be spread on water surface to form stable monolayer. It has been found that UV and IR spectra confirmed the characteristic aromatic segment, imide group and cholesteryl substituted group. In addition, the CD spectra also showed positive CD signals, which may be attributed to the chiral cholesteryl substituted groups. AFM investigation indicated some aggregated domains with the averaged height about 3.6  0.2 nm appeared. This suggested an organized structure of double molecules may be fabricated in the transferred LB films. The present results have demonstrated that the interfacial properties of luminol derivative can be modified by changing proper substituted groups of luminol, which show potential application in functional material fields such as ECL sensor.
Synthesis and Characterization of Hyaluronic Acid for Biomedical Application
Authors: Lee Dongoun , Nurunnabi Mohammed , Hwang Joon , Chung Eui Sik , Rahmatullah Mohammed , Huh Kang Moo , Kwak Kwang Soo , Lee Yong Kyu
Published: October 2012

Hyaluronic acid is a linear polysaccharide composed of glucuronic acid and N-acetylglucosamine. HA-based biomaterials secure wide-range applications in the healthcare industry. The material is found in cartilage, skin, umbilical cord, synovial fluid, as well as in the cell wall of bacteria such a Streptococcus zooepidemicus. As a consequence of these wide applications, HA production from microbial fermentation is receiving increased attention for avoiding the risk of cross-species viral infection, to have lower production cost and to favor a more efficient purification. The molecular weight is increased by adding poly-γ-glutamic acid, which inhibits hyaluronidase of medium, and the degree of purity is enhanced by a purification process using the means of dialysis membrane and organic solvent.
Synthesis of Biodiesel by Different Carriers Supported KOH Catalyst
Authors: Yang Ling Mei , Lv Peng Mei , Yuan Zhen Hong , Luo Wen , Li Hui Wen , Wang Zhong Ming , Miao Chang Lin
Published: October 2012

Transesterification of soybean oil with methanol to methyl eaters was found proceed in the presence of KOH loaded on five different oxides (CaO, MgO, Al2O3, Bentonite, kaolin) as heterogeneous catalysts. The structure and performance of these catalysts were studied using the techniques of XRD, CO2-TPD, and SEM. It was found that the 15wt% KOH/CaO catalyst provided best activity. In the presence of this catalyst, the yield of fatty acid methyl esters was 97.1%. The reaction conditions were as follows: methanol to soybean oil molar ratio was 16:1, temperature of 65 °C, reaction time of 1 h, and a catalyst amount of 4 wt%. The catalysts of KOH loaded on CaO showed a new crystalline phase of K2O. However, the catalyst of 15-KOH/CaO has more basic sites than the catalyst of 15-KOH/MgO. Therefore, the catalyst of 15-KOH/CaO has been associated with higher transesterification activity.
Synthesis Study of the Antioxidant of Tetrakis(2,4-di-tert-butyl phenyl)-4,4’-Biphenylenediphosphonite Esters
Authors: Li Yan , Zhao Jian , Yu Qing , Wang Zhong Wei
Published: October 2012

The antioxidant of tetrakis(2,4-di-tert-butylphenyl)-4,4’-biphenylenediphosphonate (TBBPP) was synthesized using biphenyl, PCl3, AlCl3, and 2,4-di-tert-butylphenol as raw materials. Phosphite esters were selected as the novel decomplex agent to isolate the intermediate of 4,4’-biphenylbisphosphorus dichloride complex from the complex it formed with AlCl3 during the reaction. The separate factors such as the mole ratio of the decomplex agent used, the decomplex temperature, and effect of decomplex agent were studied. The specifications of melting point, thermal stability and transmittance of the target compound synthesized were compared with the commercial product, and the results showed that the TBBPP synthesized in the study showed fairly better quality than the commercial one.
Kinetic Study of the Esterification Reaction of Ethylene Glycol with Phenyl Phosphonic Acid and Benzene Phosphinic Acid
Authors: Li Yan , Kong Xian Si , Wang Zhong Wei , Yu Qing
Published: October 2012

The esterification reaction kinetics of ethylene glycol (EG) with phenyl phosphonic acid (PPOA) and benzene phosphinic acid (BPA) were studied in this article. Reactions were all carried out using benzene as a water carrying agent, and the reactant concentrations were determined by titration with NaOH. The reaction mechanisms were explained respectively. Various factors that may affect the extent of reaction were investigated such as reaction time and reaction temperature. The kinetic model of the apparent reaction was built. It was found that the apparent reactions both followed the pseudo-second order mode and the activation energy wre EPPOA 62.631 kJ/mol, EBPA 32.673 kJ/mol, respectively.
The Study on Moisture Adsorption of Oxidized Activated Carbon
Authors: Wang Kang , Wang Wei Long , Lu Jian Feng , Ding Jing
Published: October 2012

Activated carbon made by clean coal and 25% coconut shell was selected to be modified with different concentrations’ HNO3. The productions were characterized by BET, XPS, FTIR and the moisture adsorption of performance is investigated by the DVSA-STD dynamic vapor analyzer. The results show that specific surface area of the activated carbon modified by the 10% concentration of HNO3 is improved 1.3 times than the unmodified one. By comparison the higher concentrations of HNO3 have weaker effects on the specific area of activated carbon. The water vapor adsorption capacity of activated carbon modified by HNO3 at 10% concentration is 1.5 times higher than the unmodified at room temperature at30% RH.
Preparation of Polycarboxylate Terpolymer High Performance Water Reducer of MA-AA-F108
Authors: Song Jia Le , Wen Hong Ping , Lv Chang Liang , Zhou Zhi Mi , Li Wei Guang
Published: October 2012

In aqueous solution, the modified polyether (F108), maleic anhydride (MA), acrylic acid (AA) as raw materials, a novel polycarboxylate high performance water reducer of MA-AA-F108 was synthesised from free radical copolymerized through oxidation-reduction initiator system. Additionally, the polymerization conditions were optimized. The results indicate that the copolymer can be prepared under such optimum conditions, i.e., 3:3:2 molar ratio of MA, AA and F108, 0.5% of the mass fraction of oxidation initiator, 0.6% of the mass fraction of reduced initiator and 0.3% of the mass fraction of regulator, the results showed that the polyether-type polycarboxylic water reducer has excellent dispersing ability.
Rapid Analysis of the Main Components of Glycyrrhizae Uralensis Fisch by UPLC/Q-TOF-MS
Authors: Shi Zhong Feng , Feng Yi Fan , Rui Wen , Wang Liang , Zhang Xiao Mei , Han Liang
Published: October 2012

A rapid method for analysis of the main components of Radix Glycyrrhizae (RG) was developed using ultra-performanceliquid chromatography with quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS). Previous study demonstrated that RG had antivirus, antioxidant，anti-tumor and other bioactivities. The separation analysis was performed on Waters Acquity UPLC system and the accurate mass of molecules and their fragment ions were determined by Q-TOF MS. Fourty compounds including triterpenoid saponins, flavonoid glycosides and flavonoid aglycones,coumarins, were identified and tentatively deduced on the basis of their element compositions, MS/MS data and relevant literatures. The results demonstrated that triterpenoid saponins, flavonoid glycosides and flavonoid aglycones were the main constituents of RG. Furthermore, an effective and rapid pattern was established allowing for comprehensive and systematic characterization of the complex samples.
Adsorption Kinetics and Thermodynamics of Methyl Orange on Ethylenediamine-Modified Chitosan Magnetic Nano-Adsorbent
Authors: Chen Yu Hong , Hu Si Qian
Published: October 2012

Ethylenediamine-modified chitosan magnetic nano-adsorbent (EMCN) was prepared and used for the sorption of methyl orange(MO). The kinetics of the sorption fitted well with the pseudo-second-order kinetics model. The activation energy of sorption (Ea) was determined to be 16.47 kJ.mol-1. Adsorption isotherms showed that the sorption process was consistent with both Langmuir and Freundlich isotherm, and the thermodynamic parameters were calculated and indicated that the sorption process was spontaneous and exothermic. The saturated sorption capacity is 247.66, 227.58, 214.19 mg.g-1 at 5°C, 25°C, 45°C(pH=5.6),respectively.
Adsorption Properties of Formaldehyde by Organic Modified Zeolite
Authors: Zheng Yun Xing , Ding Hao , Luo Hong Na , Wang Meng Meng
Published: October 2012

Stellerite was activated and organic modified by calcination and hexadecyl trimethyl ammonium chloride (CTAC) to improve its adsorpability of formaldehyde which was one of the iconic pollutants of indoor air pollution. Results showed that the optimum calcining temperature and calcining time were 300 °C and 1.5 h. The optimum amount of anticoagulant, alcohol addition, CTAC addition, bathing temperature and reaction time were 0.5%, 0.7ml, 3 times, 70 °C and 2h, respectively. The organic modified effects of stellerite were characterized by hygroscopicity test, formaldehyde adsorption experiment, scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FT-IR). All data indicated that CTAC had entered into the internal of stellerite and the adsorbability of formaldehyde had a huge improvment after organic modification.
Characterization of Lanthanum Nitrate Modified CaMgZn Mixed Oxide Catalysts for Synthesis of Biodiesel
Authors: Li Xue , Zhou Zi Yuan , Zhu Li Wei , Jiang Jian Xin
Published: October 2012

CaMgZn mixed oxide (CMZ) catalysts were modified by addition of lanthanum nitrate, and the use of modified catalysts (CMZL) for biodiesel synthesis were investigated. The conditions of biodiesel production with modified catalysts were optimized. Using optimized conditions, including lanthanum nitrate addition of 3wt.%, catalyst amount of 5wt.%, reaction temperature of 50°C, methanol to oil molar ratio of 15:1 and reaction time of 1h, the glycerol yield of 86.80% catalyzed by CMZL could be attained, which was higher compared with the CMZ catalyzed process of 82.94%. Brunauer–Emmett–Teller (BET), X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) were used to compare the modified CMZL catalyst with the CMZ bare catalyst. The results indicated that the lanthanum modified catalysts (CMZL) have excellent surface property. The modified catalysts could be suitable for commercial application.
Synthesis of 1,4-Bis(3-amino-5-trifluoromethylphenoxy)Benzene and Properties of the Polyimide Film Therefrom
Authors: Lu Yun Hua , Wang Bing , Xiao Guo Yong , Hu Zhi Zhi
Published: October 2012

Firstly, 1,4-bis(3-nitro-5-trifluoromethylphenoxy)benzene(I) was synthesized through the nucleophilic substitution reaction of 3,5-dinitrobenzotrifluoride and 1,4-dihydroxybenzene in the presence of potassium carbonate. Then, the diamine monomer 1,4-bis(3-amino-5-trifluoromethylphenoxy)benzene (II) was obtained through the catalytic reduction with hydrazine and Pd/C. These fluorinated polyimides (PI) were synthesized from the fluorinated diamine II with four kinds of dianhydrides, including pyromellitic dianhydride (PMDA), 3,3’,4,4’-biphenyltetracarboxylic acid dianhydride (BPDA), 3,3’,4,4’-oxydiphthalic anhydride (ODPA) and 3,3’,4,4’-benzophenonetetracarboxylicdianhydride (BTDA) respectively, via thermal imidization of poly(amic acid) (PAA). The structure and properties of these obtained fluorinated PIs were characterized. These experimental results showed that these fluorinated PI films exhibited excellent optical transmittance in the visible region and thermal resistance. The PI derived from ODPA showed the best optical transparency with the transmittance higher than 85.38 % at 450 nm. These PIs also exhibited good thermal properties with 5 wt% thermal decomposition temperature above 533 °C.
The Study on Application of N-P Intumescent Flame Retardant Agent in Waterborne Polyurethane
Authors: Wang Xue Chuan , Wang Li
Published: October 2012

Phosphorylation for the first generation product of hyperbranched polymer with terminal hydroxyl (HPAE1) was carried out to synthesize a type of P-N intumescent flame retardant （HPAE1-P）, with phosphorus pentoxide and phosphoric acid as phosphorylating agent. HPAE1-P was used in waterborne polyurethane MWU-T-502B-30, and then they were tested the properties of the emulsion, such as the stability, LOI, smoke density and vertical combustion performance. The results showed that the compatibility of this flame retardant agent and waterborne polyurethane MWU-T-502B-30 was very good, and this flame retardant agent could effectively improve the polyurethane flame retardant property.
The Effects of the Reaction Conditions on the Grafting Degree of SiO2-g-PMAA Particle
Authors: Zhang Ke Hong , Xiao Hui , Du Jun Juan
Published: October 2012

Modified MPS-SiO2 particle was obtained by the bonding of 3-methacryloxypropyl trimethoxysilane (KH-570) on the surface of silica gel particle. The methacrylic acid (MMA) monomers were grafted on the surface of MPS-SiO2 particle to prepare the grafting particles SiO2-g-PMAA. The effects of reaction conditions on the graft degree were explored. The results indicate that the MMA monomers can be easily grafted on the surface of silica gel particle by using the method of graft polymerization. During the graft polymerization, the grafted polymer layer is a hindrance to the subsequent graft polymerization. Then the grafting degree of the polymer under a certain condition has a limiting value. The reaction conditions, such as monomer concentration, the amount of initiator, reaction temperature, have remarkably influence on the graft polymerization of SiO2-g-PMAA.
Determination of Organochlorine and Pyrethroid Pesticides Using Membrane-Protected Multiwalled Carbon Nanotubes Solid Phase Membrane Tip Extraction
Authors: Gao Wen Hua , Li Fang Fang , Xiao Song , Chen Tu Feng , Zhang Xiao Shan , Zhang Wen Qiang , Chen Yao Wen
Published: October 2012

A microextraction technique of solid phase membrane tip extraction (SPMTE) prior to gas chromatograph was developed to determine fifteen pesticides (organochlorine （OCPs） and pyrethroid). In the SPMTE procedure, multiwalled carbon nanotubes (MWCNTs) were used as the adsorbent enclosed in SPMTE device and then several important parameters influenced extraction efficiency were comprehensively optimized. Under the optimum conditions, the method obtaine good linearity in the range of 1–500.0 and 1.5–750.0 ng mL-1for OCPs and pyrethroid pesticides, low limits of detection in the range of 0.018–1.064 ng mL-1(S/N=3). Seven target analytes are detected in river sample, none of the other samples tested show any pesticide residue. The developed method is a simple, feasible, and inexpensive microextraction technique.
Synthesis and Characterization of a Novel Alkaline Earth Metal Complex
Authors: Yang Hui Fang , Ren Shu Xia , Li Huang , Shen Jun Jun
Published: October 2012

A novel complex was obtained by self-assembly of the corresponding alkaline earth metal chlorate with a ligand, Azobisisobutyronitrile in this paper. The coordination principle of the as-prepared complex was analyzed firstly, and then its structure and thermal behavior were detected by the infrared spectrogram and TG-DTA
Synthesis of Starch Graft Copolymer Dispersant and its Application Performance in Coal-Water Slurry
Authors: Zhang Guang Hua , Zhao Fang , Li Jun Guo
Published: October 2012

In this study, a new starch graft copolymer dispersant for Chinese Shenhua coal-water slurry (CWS) was prepared by radical polymerization using styrene sulfonate (SSS), hydroxyethyl acrylate (HEA) and methyl acrylic acid (MAA) as graft monomers in oxidation-reduction initiator system. The apparent viscosity, static stabilization and rheology of Shenhua coal-water slurry prepared with the dispersant have been were investigated. The experimental results demonstrate that the CWS gives the minimal viscosity of 826 mPas at coal concentration of 66 wt%, dispersant dosage of 0.5 wt% and shear rate of 100 s-1. Bleeding ratio tests indicate the starch graft copolymer can stabilize the slurry. The rheological behavior of the prepared CWS can be described by the pseudo-plastic fluid model. On the basis of the above, the starch graft copolymer dispersant has broad prospect for the application for CWS.
"HaiYangShiYou 115" Anchor Chain Broken Wire Cable Material Test and Breakage Analysis
Authors: Cao Xin , Pan Han , Wang Hong
Published: October 2012

"HaiYangShiYou 115" chain cable in use process was found in more broken wires. Through the chemical composition analysis, mechanical property testing, fracture analysis, metallographic examination methods, the cause of the broken wire are analyzed. The results show that: the material of steel cable anchor chain mechanical performance is basic comply with the design requirements, the broken wire fracture is relatively serious wear, all send the samples of the present wear trace shape is consistent, should be the same kind of wear the way by damage, and reduced the steel wire tensile strength, lead to fracture .
Effect of Contact Characteristics on the Friction and Wear Behaviors of Stainless Steel/Copper-Impregnated Metalized Carbon under Electric Current
Authors: Ding Tao , Chen Guang Xiong , He Qiu Dong , Xuan Wen Jing
Published: October 2012

Influence of the support stiffness and contact force on friction and wear behaviors of stainless steel rubbing against copper-impregnated metalized carbon under electric current was researched on an improved friction and wear test machine. The result indicates that the support stiffness and the contact force significantly affect the friction coefficient of contact pairs, wear and surface roughness of pin samples. The appropriated support stiffness and contact force can effectively reduce friction material wear of contact couple.
Effects of Annealing on Mechanical Properties in Ultrafine-Grained Cu–Al Alloy
Authors: Long Yan , Gong Yu Lan , Ren Shi Ying , Wu Xiao Xiang , Zhu Xin Kun
Published: October 2012

Abstract. The mechanical properties and microstructure of an ultrafine-grained Cu–Al alloy before and after annealing are investigated. Ultrafine-grained Cu–Al alloy samples are processed by means of rolling at ambient temperature and rolling reduction exceeds 90%. It is found that the strength of ultrafine-grained Cu–Al alloy increased rather than decreased after annealing for 1 h in the temperature range between150°Cand 300°C.Based on the microstructures observation of samples, it can be known that both the grain size and dislocation density have main effects on hardening of ultrafine-grained Cu–Al alloy which result from annealing. These investigations showed that the annealing hardening effect can be explained by the change of dislocation density and twin density.