bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in Air Quality of the Yuxi City Urban Area
Authors: Qiu Cheng , Chen Hong , Ye Chun Li , Yang Yan Jun , Ye Chang Bing
Published: August 2014

Air pollution causes health problem. The paper simply analyzed the changes of air quality in the Yuxi city urban area from 2006 to 2012. In the Yuxi city urban area between 2006 and 2012, SO2 levels increased about 43.9 percent; NO2 levels increased about 13.3 percent; PM10 levels in 2012 decreased about 1.5 percent. By evaluating the air quality in the Yuxi city urban area, the results showed that air quality index was the maximum in 2009, and the quality of the air in Yuxi became worse from 2006 to 2012, air pollution in 2009 was the heaviest between 2006 to 2012. After adopting P.R.C EPA air quality standards (GB3095-2012) in 2013, the first air pollutant in Yuxi is PM10, and then it is SO2 among SO2, NO2 and PM10.Much should beend done to reduce the amount of PM10 and SO2 released.
Research on Methane Fermentative Residue with Material Properties for Raising Pigs
Authors: Ji Xi Yan , Zhang Wu Di , Yin Fang , Liu Shi Qing , Wang Chang Mei , Zhao Xing Ling , Liu Jing , Yang Hong
Published: August 2014

Methane fermentative residue is comprised of biogas slurry and biogas residue. It is important by-product of methane fermentative. It contains rich nutrients such as N,P,K, amino acids, humic acid, B vitamins hormone-based active substance. Add the methane fermentative residue (MFR) into the feeding-stuff can increase the efficiency of it. And it also can improve the quality of the pork. The family who owned the household biogas plant want raise pig will make the ecological agriculture come true if they recycle and reuse the methane fermentative residue.
Corrosion Behavior of 3Cr Steel in Different Water Cut
Authors: Qiu Zhi Chao , Liu Xiang , Zhang Na
Published: August 2014

Corrosion experiments were done to test the corrosion behavior of 3Cr steel in different water cut content. The experimental result shown that with the increase of water cut, the corrosion rate was increase especially in the high water cut environment. From XRD and SEM analysis result, the corrosion composition was changed with the water cut content. The corrosion film became less protective with the increase of water cut.
Thermal Entanglement Entropy Signature of Spin-Peierls Transition in Dimerized Isotropic XY Chain with Multi-Spin Interactions
Authors: Huang Hai Lin , Ding Lin Jie , Sun Zhao Yu
Published: August 2014

The finite-temperature entanglement entropy for an alternating spin-1/2 chain with multi-spin interactions is investigated by means of Green’s function theory combined with Jordan-Wigner transformation, to identify the spin-Peierls (SP) transition. It is found that the two-site thermal entanglement entropy is a useful tool to characterize theSPtransition. In addition, the competition between multi-spin interaction and Peierls-dimerization plays a central role in the critical phenomenon of the system.
Strengthening of RC-Brick Masonry Walls with Opening Using Basalt Fiber Reinforced Polymer
Authors: Lei Zhen , Qu Jun Tong , Wang Yong
Published: August 2014

FRP strengthening technique provides a promising alternative for masonry structures. This paper presents research results of quasi-static tests investigating the in-plane mechanical behavior of RC-brick masonry walls with opening strengthened with basalt fiber reinforced polymer (BFRP). Two half scale RC-brick walls were constructed, one without any strengthening scheme served as the reference specimen, another one was directly strengthened with BFRP in mixed strengthening configuration. All specimens were tested under low frequency cyclic loading. BFRP can effectively improve the lateral strength of the wall by a factor of 0.16, and the improvement in the lateral deformation capacity was much significant. The seismic performance of the composite wall strengthened with BFRP can exceed the unreinforced reference, which verifies the effectiveness of BFRP strengthening technique to strengthening RC-brick composite masonry structures in seismically endangered regions.
Preparation and Properties of the Phase Inversion Emulsification of Epoxy Resin
Authors: Zhou Hao Ran , Fang Xiao Jiao
Published: August 2014

The phase inversion process is a kind of efficient technology of emulsifying, it make its emulsifying ability to maximize by the means of control the factors of the HLB, the concentration of emulsifier, the ratio of emulsifier and oil and the temperature of emulsify. In this paper, the epoxy resin E-44 and polyethylene glycol used as materials, potassium persulfate as the catalytic agent, then we obtained the waterborne epoxy resin emulsion. The synthetic conditions of emulsifier, the mechanical stability and water-solubility of the emulsion were researched. Then the optimal amount of the emulsifier was determined and the modified emulsion was characterized, the particle size and viscosity were tested at the same time.
Tangent Stiffness Matrix of Spatial Beam Element Considering Bend and Torsion Coupling Effect
Authors: Du Liang , Lan Peng , Lu Nian Li
Published: August 2014

Based on the spatial beam-column differential equations, the slope deflection equations considering second-order and bend-torsion coupling effect are established. The additional moment caused by torsion and bend deflection are taken into account. Then the finite element pattern of spatial beam-column considering the couple effect of torsion and bend is given. The tangent stiffness matrix and relevant program for nonlinear analysis are further obtained. By the nonlinear calculation and stability analysis of single component which has high accuracy or precise solution, the precision of the FEM model given in this paper is verified by comparing the results with that given in references.
Monitoring and Analysis of a Deep Excavation in Hefei
Authors: Wang Xiao Qiang , Zhao Li Jun
Published: August 2014

A deep excavation in Hefei is proposed in this paper. Some useful conclusions are drawn through the analysis of the measured results including displacement of retaining structure, axial force of horizontal support and settlement of the surrounding buildings. It is useful for design, construction of similar engineering.
The Impact on the Surrounding Buildings of a Deep Excavation in Hefei
Authors: Wang Jia Yang , Wang Xiao Qiang
Published: August 2014

According to the building settlement monitoring around the base pit, research the deep base pit excavation impacting on the surrounding buildings. Take Hefei subway station base pit project as example, by way of an adjacent residential building whole process of excavation monitoring, research the impact of deep excavation on the surrounding buildings. Timely feedback to the construction unit, to ensure the smooth construction of pit, and provides a reference to design and construction of deep foundation pit.
The Leakage Causes and Improving Measures of CB Series of Gear Oil Pump Based on Mechanical Mechanics
Authors: Qin Tao , Wang Feng Lan
Published: August 2014

When gear oil pump works, oil chamber is filled with high pressure oil, gear moves between housing and sealing devices and must maintain a certain gap between them, so that leakage is inevitable. In this paper, from structure and working principle of gear pump, the main factors influencing its leakage are spindle end gap, face clearance, radial clearance and the gap of the tooth contact surface. Taking effective measures to control the gear oil pump clearance and improve the working efficiency.
Study on Double Long-Primary Short-Secondary Linear Induction Motor for Magnetic Elevator
Authors: Gao Su Mei , Ju Quan Yong , Mu Fu Yuan
Published: August 2014

A new kind of magnetic elevator is presented in this paper, and the traction force of elevator is provided by the double long-primary short-secondary linear induction motor. The elevator has the advantages of simple structure, less heat, good adaptability. The circuit model of traction motor is established. Magnetic elevator running speed curve is analyzed, and the VVVF control system of linear induction motor for magnetic elevator is designed, and the double long-stator windings are piecewise controlled. Through simulation, the feasibility of the magnetic elevator is verified. The paper laid the solid foundation for the further application.
Simulation on Magnetorheological Suspension Structure of Automotive
Authors: Wang Xiao E , Chen Zuo Yue
Published: August 2014

Isolation Control System Based on MRF magneto-rheological dampers analyze the structure and mechanical properties for engine isolation, the establishment of magnetorheological damper damping force of the theoretical model to clarify the magnetic current variable damper structural parameters, the motion parameters change its relationship performance impact of electromagnetic fields on the magneto-rheological dampers for numerical calculations. Research magnetorheological engine mounts intelligent control, real-time damping force adjustment, so that the vibration of the engine is transmitted to support the most effective attenuation of the time.
Research on the Work Space Optimization of the Six Bar Parallel Machine Tool
Authors: Hou Jiang Hua , Duan Cui Fang
Published: August 2014

The paper analyzes the technical characteristics of two kinds of six bar parallel machine tool workspace, gives the technical parameters of the main elements of the piston rod and the platform. Through the research ,the paper obtains the maximum and minimum overhang of the piston rod and the best angle range of the platform in the air and optimizes the structure parameters and workspace of the Six bar parallel machine tool.
Research on Wind Turbine Blade Load Based on the Analysis of Structural Dynamics
Authors: Xu Zhi Qiang
Published: August 2014

Wind energy technology is an integrated technology, which involves aerodynamics, structural dynamics, meteorology, mechanical engineering, electrical engineering, control multiple disciplines technology, materials science, environmental science and other areas. This paper studies the structural dynamics of the wind turbine. On one hand, modern wind turbine is composed of various interacting components and subsystems, and its aerodynamic rotor design technique involves controlling a wide range of areas systems, mechanical systems, electrical systems. On the other hand, the wind turbine has characteristics different from the usual mechanical systems. Wind turbine power source is natural randomness of strong wind, The leaves are often run in a stall condition. The system has a strong stochastic dynamic process. The transmission system irregular power input is abnormal . The main structural components exposed to several times higher than normal rotating mechanical fatigue loading. Thus the unique characteristic of dynamics of the wind turbine is formed . Analysis of wind turbine blade load dynamics of basic research carried out in this article by means of an appropriate structure coordinates.
The Property Analysis of the Leaf Spring Based on Abaqus and Elastic Mechanics
Authors: Liao Shu Hua , Su Hai Liang , Wei Ting Ri
Published: August 2014

In the paper, use the finite element software to simulate the loading of a car's rear leaf spring in the actual test, analyze the stiffness and free camber of a leaf spring, compare with the data of experiment. which fully approved that this theory can be applied to the analysis of a leaf spring's actual exploitation and design. At the same time, extract the displacement of the lug and rear axle point, analyze its trajectory based on the multi-body dynamics. It offered reference for design and development of the same types of leaf springs in the early period. Keywords: Leaf spring Finite element Stiffness characteristics Free camber
Signal Detection Technology in Shipboard Power System with Grounding Fault Line Selection by Current Travelling Waves Based on Mathematical Morphology
Authors: Chen Liang , Shen Bing , Zhang Xiao Feng
Published: August 2014

Aimed at the prominent problem of algorithm complexity, massive operation scale and difficulty in applying the wavelet transform in the field of travelling waves signal detection, this paper presents a current travelling waves singularity signal detection method for shipboard power system single-phase grounding fault (SGF) line selection using morphological gradient technology for extracting transient fault features. The simulation results conducted by EMTPWorks have proved that the method presented in this paper have a veracity as well as reliability in grounding fault line selection. It is of high practical value.
The Overview on Sticking Breakout Behavior for Thin Slab Continuous Casting
Authors: Li Hui Rong , Sun Li Gen , Ai Li Qun
Published: August 2014

Breakout is the most detrimental event associated with the continuous casting process, with the overview of the sticking breakout behavior, a lot of valuable things had been acquired. For the mechanism of the sticking breakout forming, the key for the breakout prevention is decreasing the probability of the hot spot; the content of the carbon or alloy element, the wear and tear of the mould corner, the mould flux, the fluctuation of the casting speed and the fluctuation of the meniscus are easy to cause the sticking; and with high casting speed and the funnel mould, the thin slab continuous casting is more easier to lead to sticking breakout than the normal strand.
Data Processing for Correlation Analysis between Extracurricular Sports Activities and Mental Health in Rural Middle School Students
Authors: Su Yan Qin
Published: August 2014

In order to explore the relation between mental health status and extracurricular sports activities, using data processing method to analyze 657 middle school students in rural middle school in Sichuan participated in this survey. They were selected using cluster sampling. The results indicated (a)there were significantly insufficient in extracurricular sports activities in days each week,duration each session and exercise intensity rural middle schools students,(b)there was some extent mental health deficit in rural middle school student, and (c) the mental health has significant correlation with days of sports activities each week ,duration each session and the intensity of sports activities.
Research on Computer Technology with Informatization in Higher Education
Authors: Zhou Ling
Published: August 2014

Abstract: With the rapid development of computer technology and theoretical concepts and constantly updated network technology, computer technology applications in the field of education more widely. Application of computer technology in higher education, not only can improve teaching effectiveness and efficiency, but also enrich the teaching content and teaching methods to stimulate students' interest in learning, thus improving the quality of teaching.
Design of Network Information Security System
Authors: Zhang Ya Na , Han Li , Cao Xin
Published: August 2014

In this paper, in order to design the system based on the principle of the site, focusing on advanced systems, scalability and reliability at the same time, the introduction of design requirements and the target site system from two aspects of the system architecture and modular design of the system discussed and design. Full system architecture is designed for secure site information. The results show that the system can guarantee the availability and security of the site and prevent a variety of adverse information is released and the view to improve the quality of service of Web sites and Web applications.
Applied-Information Technology with DSP-Based Recognition Algorithms of Driver Fatigue
Authors: Deng Zheng Hong , Jing Rui Jun , Liu Li Yan
Published: August 2014

To be effective, and real-time detect fatigue, system based on the DM642 module,platform and infrared camera collects images and detects fatigue. the optimization algorithm is implementated on the special DSP library. That using skin color Gaussian model, connected domain and integral projection method detects eyes. Target area is divided by adaptive threshold.we use sobel edge detection and extraction of integral projection to extract eyes closure degree, and use PERCOL to judge fatigue. Experiments show that the system improves the computing speed and precision and realizes the real-time detection purposes.
The Composition Cement Binder with the Use of the Synthesized Aluminosilicates
Authors: Loganina Valentina Ivanovna , Makarova Ludmila V. , Tarasov Roman V. , Zhegera Ch.V.
Published: August 2014

The effectiveness of the use of the synthesizable aluminosilicates in cement composites as the modifying additive, regulating the structurization and increasing the operational properties of cement systems is investigated. Nature of change of the index рН of a liquid phase of cement systems with the use of the synthesized aluminosilicates is studied. The information about a thermal emission kinetics at hardening cement composites are provided.
One of the priorities of the modern building materials science is the development of efficient building materials with the high operational properties. The solution of this problem base on purposeful formation of the material structure as heterogeneous, multiphase system of the complex hierarchy. One of the directions of properties management of this system is the modification of their structure by nanosized particles [1, 2, 3].
Information Processing in Design and Testing of Financial Early Warning Method of Listed Companies in China - Based on the Logistic Regression Analysis
Authors: He Yu Mei , Li Meng , Xu Xin Yi
Published: August 2014

Information processing is of essential importance for an effective financial early warning model. In order to design the model of financial early warning for listed companies, we selected the 120 listed companies as research samples, chose the necessary information and relatively financial indexes and detected them by K-S normality test, then separately analyzed the results by One-Sample T test and Nonparametric Test. Through the discriminant analysis to the correlation analysis, we can identify the independent variables of logistic analysis, introduce in the quadratic term and cross term for logistic regression analysis. Applied the model in financial crisis prediction of the listed companies in China, the empirical results indicate that the prediction accuracy is 87.4%. The model from relatively information and financial index provides a kind of early warning method, which is simple practicable and scientific, for estimating the business status of a company.
Intelligent Optimization of Optimal Operating Mode in the Production Process of Copper Converter
Authors: Shao Yi Yuan , Liu Wen Bin
Published: August 2014

In order to enhance the standard of copper converter operation,operating modes are employed to describe a group of operating parameters which need to be decided on line, and an intelligent optimization way based on neural network and improved chaos genetic algorithm for operating modes is presented. At first, the optimal samples is sieved from the historical sample set. Secondly, the functional relationship with optimization objective and technological parameters is drilled by a neural network model. At last, chaos genetic algorithm with chaotic variables is adopted to seek the optimal operating mode. This method is applied to real-time optimization of copper converter operating parameters.The running results show that the yield of converter raises by 5.9%, and the quantity of the disposed cool materials increases by 7.7%.
Research on Wireless Sensor Networks with an Improved DV-Hop Localization Algorithm Based on Weighted Processing and Error Modification
Authors: Zhou Hang Xia , Cui Chen , Ye Jia Jun
Published: August 2014

Regarding the conventional DV-Hop algorithm easily caused big error in a network topology scenario, this paper proposes an improved DV-Hop localization algorithm comprehensive consideration of all anchor nodes average one-hop distance and normalized weighted, use anchor nodes as unknown nodes calculating error and use the error optimizing accuracy. Theoretical analysis and simulation results show that the proposed algorithm has better locating performance in locating precision and precision stability.
Robust H∞ Fuzzy Control for Nonlinear Networked Control System and its Application
Authors: Wang Qing Feng , Wang Hong Bo
Published: August 2014

The paper studies the effect of networks with transmission delay in the feedback loop of a nonlinear networked control system (NCS). The nonlinear system is modeled by a T-S fuzzy model, and transmission delays are modeled by a finite state Markov process. The fuzzy controller’s membership functions can be different from the plant’s. The membership functions of the plant and the fuzzy controller are incorporated into the controller design. System performance is measured via an norm from disturbance to error and the controller is computed by sum of square approach. Finally we applied these results to an inverted pendulum system. Theoretical analysis and simulation results show that the control strategy studied in this paper is effective and feasible.
Research on Stability of Intelligent Control System for Turning with Management Method
Authors: Zeng Li Xin , Lu Hong Mei
Published: August 2014

With application in turning, this paper presents a stability control system which based on a new strategy. It works by permanent assessment of the operating point position system which is relative to the stability limit and process parameter, in-process modification. For example, this point is always placed in the stable domain that gives the highest process performance. In the case of turning, here approached: first, this area is the stability limit proximity; second, the operating point system position is determined by assessing a cutting force monitored signal feature, last, it changed this position by modifying the cutting edge setting angle, the feed rate, and the cutting speed, as it follows: when the risk of the stability limit is imminent, the setting angle is increased, which followed by a feed rate diminishing and then by a worked piece rotation speed reduction, after surpassing the risk, the three variables modification is reversed, through this way the chatter onset could be avoided and the performance can be kept in every moment at the highest level. The system was experimentally implemented on a transversal lathe. The results of tests about dedicatedly designed specimens are showing a machining productivity that significantly increases, in conditions of a stable cutting process. Without important modifications, it can be easily added to the existing CNC machine tools.
Unfolding Method of Non-Developable Surface for Sheet-Metal Design
Authors: Sun Bo , Wang Xiao Long
Published: August 2014

The organized vertex coordination of the triangular surfaces is obtained by the meshing method in the 3D kernel based developing environment. To optimize the flattened form, the energy method is used to find the reasonable unfolding scheme, which seeks the solution to minimize the deforming energy generated when flattening the triangular surfaces. This algorithm is not the fastest one, but the versatile one especially for the non-developable surface with a large bending degree. With the unfolding method and the 3D kernel environment, the 3D unfolding system for the arbitrary surface satisfying the requirements is constructed.
Metallogenic Features Modeling and Deep Mineral Exploration of Laochang Ore Field in Ge Jiu
Authors: Wu Zhao , Chen Jian Ping , Xu Meng Long
Published: August 2014

By analyzing metallogenic regulation of the deep skarn ore bodies in Laochang ore field,3D metallogenic features model was established with 3D visualization technology. With “the cubic predicting model” method, the major ore-controlling factors in deep include granites, strata, faults and chemical elements abnormal. We delineated prospect area and outlined ten targets through evidence weight method. Calculating the ore-containing probabilities and the quantities of mineral resources ,it realized prediction of mineral resources on quantity, position and probability. It is important for deep mineral exploration of Laochang ore field in Ge jiu.
Characteristics of Electron Structure and 4f Orbital of Rare Earths and Their Reinforcement of Wastewater Degradation
Authors: Kuang Ju Chi
Published: August 2014

The reason why rare earth (RE) can play a role of strengthening catalytic degradation of wastewater has always been the topic of common interest for experimental and theoretical chemists. First it discussed the structural features and acts of RE elements, such as 4f orbitals whether to take part in bonding, their hybrid approach and the bonding ability of the hybrid orbitals. Then the paper took attention to how REs to reinforce catalysis for degradation of wastewater, including following aspects: REs' reinforcement on catalytic wet oxidation ability of wastewater, REs advancing H2O2catalytic oxidation ability to deal with wastewater, REs improving TiO2photolysis efficiency of organics, and REs further improving role of O3/TiO2/UV photocatalytic degradation for wastewater. Finally there were the conclusion and prospect. Looking to the future, the quantitative understaning the 4f orbital of RE contribution still need to rely on the further development of quantum chemistry theory and method.
Research on Energy Saving for Multi-Back after Blending Water from One Station System’s Parameters Optimization
Authors: He Feng Yun , Wang Fan
Published: August 2014

The process of multi-back after blending water from one station is used in a block of Daqing oilfield, for saving energy, reducing consumption and easy to manage. For this block’s water blending system, research on its blending parameters optimization is carried on. According to the block’s characteristic of the process, the characteristic of energy cost minimum as objective function, setting up the multi-back after blending water from one station system’s parameter optimization mathematical model[1]. The model belongs to nonlinear programming problems with constraints, the mixed penalty function method and the improved conjugate direction method are used to solve the model, the optimum water blending temperature is determined by optimization calculating as 62.1°C and quantity of blending water a year is 1.13×105 t . By doing so, running costs saved 220,000 yuan per year to achieve the goal of saving energy and reducing consumption.
Research of Oracle Database Performance Optimization in University Educational Management System Based on Information Technology
Authors: Wu Yun , Zhang Zhi Xiong , Zhang Wen Li
Published: August 2014

University educational management system is the core part of digital campus, this paper uses Oracle 11g database to study the educational management system, Oracle database performance directly impacts on the performance of management system, so the Oracle performance optimization is more and more attention to, the database performance optimization begins from the database design stage, through the database deployment stage and SQL realize process's optimization, to realize university educational management system Oracle database performance optimization goals.
Analysis of the Pollution Characteristics and Influence Factors of PM2.5 in Chinese Main Capital City
Authors: Guo Yuan Ai , Zhang Xiao Ming
Published: August 2014

In this paper, we choose the data of 24 capital cities of Chinese Mainland, with information on PM2.5 and the meteorological conditions, using the Mixed Effects Model to analysis the Pollution Characteristics and Influence Factors of PM2.5 in Chinese main capital city. The results show that the PM2.5 level has a significant seasonal characteristic; the level of PM2.5 in winter is higher than that in spring. And the weather conditions also have significant effects on the PM2.5 level.
Research on Energy-Saving and Environment Protection with the Comprehensive Exploitation of Hengyang Tourism Resources Based on the Perspective of Low-Carbon Tourism
Authors: Dong Zi Xiong , Wu Yue
Published: August 2014

In the process of tourism development, the constant damage of tourism resources and ecological environment has aroused people’s wide concern. Low- carbon tourism is an important means for tourism industry to realize energy-saving and environment protection. Hengyang is a city rich in tourism resources, cultural heritage, and obvious traffic advantages. The comprehensive exploitation of Hengyang tourism resources exerts great significance on promoting transformation and upgrading of Hengyang tourism industry, speeding up the pace of constructing a powerful tourism city and further developing and expanding tourism in Hengyang .
Energy Saving for the Construction and Demonstration of the Evaluation Index System of Low Carbon Economy in Hunan Province
Authors: Yang Yu Xiang
Published: August 2014

Facing climate change, developing low carbon economy has become an inevitable solution for China. This essay tries to establish the evaluation index system in five aspects, namely low carbon energy consuming level; low carbon technological level; economical developing level; social support level and natural environmental level. Meanwhile, by using factor analysis method and analytic hierarchy process, it comes to the conclusion that the low carbon development level of Hunan province is on a trend of increasing improvement, nonetheless there remains room for amelioration to reach the low carbon economy standard，and Finally, it propose the measures for energy saving.
Energy Attitude and Energy Instructional Strategy of Science and Technology Teacher Based on Environment Protection in Junior High Schools in Taiwan
Authors: Weng Yung Jin , Chang Hui Ju , Wu Tian Ynan
Published: August 2014

The purpose of this study was investigated the relationship between information education of energy attitude and energy instructional strategy of science and technology teacher in junior high schools in Taiwan. With the questionnaires and statistic analysis of 618 teachers, we found the energy attitude of teachers is positive and they made good use of energy instructional strategies. The energy safe attitude of teachers whose age are 41-50 years old were better than those below 28 years old and 29-33. The energy safe attitude of teachers who worked for 16-25 years were better than those below 5 years and 6-15 years. And the saving energy attitude of teachers who taught in school above 49 classes were better than those below 12 classes. At the same time we found the infusing question strategy and cognitive-oriented strategy of teachers whose age were 41-50 years old made better use of than those age were 29-33 years old. The energy attitude could forecast the using situation of energy instructional strategy especially in infusing question strategy, cognitive-oriented strategy and total energy instructional strategies.
Crystallization Kinetics and Microhardness of MgO–Al2O3–SiO2 Glass Ceramics with Low Melting Temperature
Authors: Lu Qiang , Liu Shu Jiang
Published: August 2014

The authors report a deferential scanning calorimetric study of MgO–Al2O3–SiO2glasses which possess low melting temperature due to introduction of some quantity of B2O3, Li2O and CaF2. It is shown that the content of Li2O has a strong impact on the overlapping extent of the rates of nucleation and crystal growth. High-quartz tends to precipitate at low temperature (~1173 K) for the studied glasses, irrespective of Li2O content. With increasing annealing temperature, spodumene and cordierite form as main crystalline phase for the samples with high and low Li2O content, respectively, and then cristobalite crystals occur for both glass compositions. Microhardness firstly increases and then decreases, depending on crystalline phase sequence, and a maximum microhardness value is obtained to be 10.5 GPa.
Synthesis of Symmetrical Dipurine-Nucleoside Diphosphates from the Corresponding Nucleoside Phosphoropiperidates
Authors: Li Xiao Chuan , Gong Shan Shan , Sun Qi
Published: August 2014

A general and efficient method for the preparation of symmetrical dinucleoside diphosphates with purine bases has been developed. Ap2A and Gp2G were synthesized from the in situ hydrolysis of corresponding nucleoside 5′-phosphoropiperidates with 4,5-dicyanoimidazole as the activator. This method features easily accessible starting materials, simple procedures, and good yield.
Efficient Synthesis of Pyrimidine-Nucleoside Monophosphates from H-Phosphonates
Authors: Sun Jian , Gong Shan Shan , Sun Qi
Published: August 2014

Two natural pyrimidine-nucleoside 5′-monophosphates have been synthesized from the corresponding nucleoside 5′-H-phosphonate monoesters via a one-pot reaction in high yields.31P NMR tracing experiments revealed that after H2O was added, iodophosphate intermediates were hydrolyzed immediately to generate nucleoside 5′-monophosphates almost quantitatively. Unlike the reaction in pyridine, the iodine oxidation reaction in DMF followed by immediate hydrolysis formed only a very small amount of dinucleoside diphosphate self-condensation byproduct.
Efficient Synthesis of Bis-Functionalized 1,8-Diaminooctane Derivatives
Authors: Gong Shan Shan , Sun Qi
Published: August 2014

A practical solvent-free method for the preparation of 1,8-diaminooctanes functionalized with phosphonate esters has been developed. The synthetic conditions based on the Kabachnik-Fields reaction were investigated with different reactant ratios and temperatures. The experimental results showed that the solvent-free condition with moderately elevated reaction temperature was optimal for the synthesis of this type of compounds.
Synthesis of Titanium Dioxide Nanoparticles in Natural Rubber Latex Medium
Authors: Tan Kim Song
Published: August 2014

The feasibility of synthesizing TiO2 nanoparticles using tetramethylammonium hydroxide (TMAOH) stabilized titanium tetraisopropoxide (TTIP) in natural rubber latex medium was investigated. The TiO2 nanoparticles were separated using centrifugation and were characterized using SEM, TEM and XRD. It was found that the weight fraction of latex loaded in the reaction vessel affects the shape and size of the TiO2 particles
Morphology Controlled Ionothermal Synthesis and Characterization of Ceria Nanomaterials
Authors: Lee Yi Tong , Chowdhury Sujan , Bustam Mohamad Azmi , Mutalib Mohammed Ibrahim Abdul , Norani Muti Mohamed
Published: August 2014

Crystalline ceria nanomaterials have been successfully synthesized through ionothermal treatment method. Morphology of the ceria nanoparticles are confirmed with scanning electron microscopy (SEM), transmission electron microscopy (TEM) with an average size of 6-30 nm and with the N2 adsoprtion-desorption technique in the range of 46-62 m2g-1 in the presence of ionic liquid as base on acetate anion, trifluoroacetate anion, dicyanamide anion as organic linker, cerium nitrate hexahydrate as precursor and ammonia. It was found that the cerium oxide synthesized by acetate anion based ionic liquid has cube shape morphology and gradually form belt shape as elevated the hydrothermal treatment temperature. Cerium oxide synthesized by trifluoroacetate anion based ionic liquid remains its cubic morphology even at elevated temperature. Whereas, cerium oxide synthesized by dicyanamide anion based ionic liquid, ceria particles agglomerate and form irregular structures. The synthesized ceria nanocrystals show better performance for the degradation of methylene blue.
Characterization of Nanocrystalline p-CuO/n-Si Hetrojunction Prepared by RF-Sputtering
Authors: Elfadill Nezar Gassem , Hashim Md. Roslan , Chahrour Khaled M. , Wang Chun Sheng
Published: August 2014

Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";}Nanocrystalline cupric oxide (CuO) film was prepared by sputtering of pure copper metal on n-type single crystalline Si substrate under argon-oxygen ambient. Structural and morphological analyses of the as-deposited CuO films were performed by X-ray diffraction (XRD) diffractometer and Field Emission Scanning Electron Microscopy (FESEM). The results show Single crystalline granular nanocrystalline (002) CuO films, with 18 nm crystallite size. Current-voltage (I-V) and capacitance-voltage (C-V) measurements were performed for p-CuO/n-Si hetrojunction. Diode parameters such as saturation current (Is=9.5E-6 A) and ideality factor (n=1.86) were extracted from the dark I-V characteristics. Potential barrier height of the junction (ϕi=1.1V) was revealed from (1/C2- V) plot. Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";}
Deposition of Gold Nanoparticles on Linker-Free Silicon Substrate by Spin-Coating
Authors: Gorji Mohammad Saleh , Khairunisak Abdul Razak , Cheong Kuan Yew
Published: August 2014

Colloidal gold (Au) nanoparticles (NPs) deposition on silicon (Si) substrate is highly affected by the deposition technique and surface properties of the substrate. Spin-coating technique has been proven to be an efficient approach in terms of cost, time and maintaining the quality of the deposition. However, to prevent the agglomeration of NPs and obtain desirable density and distribution of NPs on the substrate, precise control of the spin-coating parameters is required. In this study colloidal Au NPs were spin-coated onto a modified, yet linker-free Si surface. By controlling the spinning speed, acceleration, dwelling time, and the volume of NPs colloidal solution, the density and distribution of the NPs on Si were optimized. Scanning electron microscope was used to investigate the NPs density in each step of the process. Results showed that the distribution of NPs on Si substrate is highly dependent on the spinning speed, duration, and acceleration rate as well as surface properties of Si substrate.
The Effect of Crystallinity of Nanoporous WO3 on the Intercalation and Deintercalation of Li+
Authors: Ahmadi Ehsan , Azhar Mustaffa Ali , Anwar Dede Miftahul , Rozana Monna , Lockman Zainovia
Published: August 2014

Nanoporous anodic WO3 was annealed at three different times of 1h, 2h, and 3h at a constant temperature of 500oC. This was to investigate the intercalation and deintercalation behaviour of Li+ in this annealed nanoporous oxide. The as-anodised WO3 is amorphous and after annealing, monoclinic WO3 was observed with much higher degree of crystallinity when the time of annealing was increased from 1h to 3h. By electrodiffusion of Li+ in the nanoporous structure, an ion exchange between fully oxidized states (W6+) which is the octahedral coordination dominates (WO6) and Li+ could happen. This causes changing of the colour of the yellowish WO3 to bluish WO3.Li2O. This work showed the effect of annealing time on intercalation of Li+ ion with WO3, however crystallinity can play a good role for electron movement, it cause a decrease in Li+ ion interaction with WO3.
Finite Element Analysis and Preliminary Fabrication of Flexible Membrane with Embedded Magnetic Nanoparticles
Authors: Jumril Yunas , Muzalifah Mohd. Said , Burhanuddin Yeop Majlis , Bais Badariah
Published: August 2014

In this study, mechanical characteristic of flexible polymer membrane embedded with nanomagnetic particles is analyzed using COMSOL Multiphysics 4.3. The mechanical properties of the membrane is studied by considering the magnetic particles as matrix structures embedded inside the polymer. The target of this work is to realize a new type of magnetic actuator that is able to generate a strong magnetic field and has large mechanical deformation capability as well. On the other hand, the flexible membrane properties should be optically paternable and display very high magnetic sensitivity. Therefore the study is focused not only to analyze the membrane properties but also the technique to fabricate the membrane for MEMS actuator. In this work, the magnetic force acting on the membrane, the length and height of the membrane, and the total volume of Ni particles were set to be constant. A good agreement between simulation and calculation on maximum membrane deformation without particle content was observed. It is shown that by having Ni particles embedded in polymer membrane, the deformation capability was greatly increased up to 30.9 μm. Therefore this study has proven that the smaller size of the magnetic particles with the planar structure arrangement and homogenous distribution of embedded particles can enhance larger membrane deformation. The fabrication concept of the membrane and material synthesis are also introduced. The results obtained in this study will have an important role in the development of electromagnetic actuator for fluids injector integrated in Lab-on-Chip system.
Glass Fibers with Multi-Functional Capabilities for Engineering and Environmental Applications
Authors: Chen Lin , Hao Bin , Ma Peng Cheng
Published: August 2014

Glass fibres with multi-functional properties were developed by using i) Polymer-based nanocomposites containing epoxy, carbon nanotubes and graphene, and ii) Titanium dioxide nanoparticles. The mechanical, electrical, barrier and photocatalytic performance of fibres were studied. Raman and electrical responses of fibres under mechanical load were coupled for in situ sensing of deformation in composite structure. The low cost and excellent flexibility of glass fibres make them ideal materials as supporter to deposit photocatalytic nanoparticles for the removal of organic pollutants in water.
Tensile Properties of Poly(L-Lactic) Acid(PLLA) Blends
Authors: Eawwiboonthanakit Netnapa , Jaafar Mariatti , Hamid Zuratul Ain Abdul , Todo Mitsugu , Lila Banhan
Published: August 2014

Poly (L-lactic) Acid (PLLA) is one type of degradable polymer which mostly used for bioplastic. PLLA has strength and modulus comparable with another commercial polymer and not degrade in general environment, however PLLA exhibits brittle fracture. In the present study, blending between PLLA with other polymers was carried out to improve the brittleness of PLLA resin. Polymers that been used in the blending process are synthetic rubber, waste rubber, acrylonitrile butadiene styrene (ABS) and polylactic acid microsphere. Blend ratio (98/2) was considered in the study . The tensile properties and morphology was investigated using tensile testing and field emission scanning electron microscope (FE-SEM). It was found that the addition of PLA microsphere shows the highest tensile strength and elongation at break and good Youngs modulus. While waste rubber and synthetic rubber exhibit the lowest tensile properties. In general, it is found that the toughness of PLLA can be improved by blending method.
The Influence of Starch Gelatinization on Mechanical Properties of Natural Rubber Latex Films
Authors: Yahya Siti Rohana , Rashid Azura A. , Azahari Baharin
Published: August 2014

The addition of starch in natural rubber (NR) latex films tends to decrease the mechanical properties of NR latex films due to poor dispersion of the fillers. As an alternative, starch was gelatinized before being added into NR latex compounds. The dispersion of 10% starch was mechanically prepared through ball milling together with dispersing agent. The other dispersion of 10% starch was gelatinized using alkali. The influenced of ball milled starch and alkali gelatinized starch filled NR latex films were studied through scanning electron microscopy, tensile properties, tear strength, and swelling properties. The rough freeze fracture surface with less agglomeration of fillers was observed on the alkali gelatinized starch NR latex films. The NR latex films filled with alkali gelatinized starch showed improvement in tensile properties, tear strength, and swelling resistance compared to the ball milled starch NR latex films. It can be concluded that the alkali gelatinization improved the dispersion of starch in NR matrix thus enhanced the mechanical properties of NR latex films.
Chemical Depolymerisation of Natural Rubber in Biphasic Medium
Authors: Suhawati Ibrahim , Mustafa Asrul
Published: August 2014

The molecular weight of natural rubber (NR) can be reduced via depolymerization reaction to produce liquid natural rubber (LNR) with a molecular weight less than 50 000 g/mol. In the reaction, hydrogen peroxide and sodium nitrite were added to natural rubber latex to initiate a redox type reaction which then breaks the NR chain. Low permeation of reagents into latex particles allows the degradation to occur greater at the latex particle surface relative to the inner core contributes to high molecular weight distribution (MWD) or polydispersity of the LNR obtained. In this recent works, the reaction was carried out in a biphasic medium consisting of water and toluene phases. Toluene swells latex particles as indicated by the SEM micrographs showing changes in the size of latex particles. This occurrence is suggested to increase the influx of reagents into the latex particles. Consequently, with higher permeation of reagents into the latex particles resulted in the decrease of molecular weight and lower polydispersity of the LNR obtained. Chemical structure analysize showed that the LNRs obtained were attached with hydroxyl and carbonyl groups.
The Influence of ECAP Pass through Bc Route on Mechanical Properties of Aluminum Alloy 6061
Authors: Yee Soon Vern , Hussain Zuhailawati , Seman Anasyida Abu , Syukron Muhammad , Almanar Indra Putra
Published: August 2014

Equal Channel Angular Pressing (ECAP) is one of Severe Plastic Deformation (SPD) methods used to produce ultra-fine grains. In this study, aluminum alloy 6061 in a rod shape as a result from casting process was used in the experiment. The rod samples were then subjected to ECAP, up to 3 passes, through Bc route. The die channel angle of the ECAP is 1200. The changes in the microstructure and mechanical properties of the samples deformed by 1-pass, 2-pass, and 3-pass of ECAP were investigated. The results show that as number of ECAP passes increase, the applied strain accumulated in the samples also increases and the grains change from equiaxed to elongated structure. The hardness is proportional to the number of ECAP passes, and the highest value is 107 HV for 3 passes with strain value of 2.0.
Microstructure, Wettability and IMC Formation of Low-Ag SAC Solder on Cu Substrate
Authors: Kamarudin Maslinda , Nurulakmal Mohd Sharif , Anasyida Abu Seman
Published: August 2014

This Paper Reports the Microstructure, IMC Evaluation and Wettability of Low-Ag Sn-Ag-Cu(SAC) (0.3 Wt% Ag and 0.5 Wt% Ag) and SAC305 Solder Alloys in Reflowed and Agedconditions. Reflow was Done at 250°C and Thermal Aging at 150°C For100 Hours. Microstructure of Bulk Solder and the IMC Formed at Interfacebetween Solder and Cu Substrate were Observed Using SEM Equipped with EDX. Microstructureobservation Showed Finer β-Sn Dendrites at 0.3%Ag Indicating a Possiblerefining Effect of Lower Ag on Bulk Solder Microstructure. SEM Result Showedfiner Ag3Sn Distributed in the Solder but the IMC Thickness of Bothreflowed and Aged Solder Joint Seems to Increase with Decreasing Ag Content.This could be due to Finer β-Sn Dendrites which Provide more Diffusion Paththrough Grain Boundaries and Increase IMC Thickness. Similarly, Lower Ag Content Appears to have Detrimental Effect on Wettability and Wetting Angle Ofsolder Joint.