bluuebunny/crossref_metadata_2025 huggingface dataset:
Testing, Investigation and Improvement on Formaldehyde in Decoration Housing
Authors: Tang Wen Hua , Yu Lian Hong
Published: March 2013

Based on formaldehyde testing of 100 households of Wuhan city,as well as questionnaire survey,and compared with China's "indoor air quality standards"(GB/T18883-2002), the results show that26 households reach the standard,74 households are not up to the standard, including 24 suites of high or more pollution.Analyzed the cause of excessive formaldehyde, the conclusion is that among the quantity and quality of decorated board, wall treatment mode, the quantity and quality of buying or making furniture,and vacant housing ventilation time, any of these factors are likely to cause high levels of formaldehyde, only each factor is controlled within reasonable limits, formaldehyde may be standard.Finally several low-cost,easy operation improvement measures and recommendations are put forward to help residents control or prevent indoor formaldehyde pollution.
The Research Methods Based on Emergy Theory of the Value of Natural Capital
Authors: Wang Yuan , Ma Liang , Long Zhen Yu , Sheng Lian Xi
Published: March 2013

Emergy is the condensation by the energy forming substances, is the new achievements of development of systems ecology and ecological economics in recent years. This article briefly describes the generating process of energy value theory and analysis methods, and makes a discussion on theory of emergy and regard the energy input of natural process as nature’s work. The value of substance is the condensation of work. Use the emergy as the main Dimensionless to measure the value, and regard natural ecosystems as natural capital. We discussed the new developments of the international ecology Emergy analysis methods and principles, and pointed out that the theoretical research and practical application has important scientific significance and application.
Research on Impregnated Ruthenium Catalyst of Simulation Printing and Dyeing Wastewater Treatment with CWAO Method
Authors: Liao Wei Ming , Zhong Zhan Rou , Guo Xiao Yun , Geng Xu , Xie Shu Kun , Zheng Cheng Lin
Published: March 2013

In the treatment of methyl orange simulation printing and dyeing wastewater by catalytic wet air oxidation method, the Ru series catalysts were prepared with the equal amount impregnation method. The catalyst activity and stability were characterized by the decolorization rate of the water samples, and the eluted metal ion concentration from the catalyst of the water samples. XRD, SEM, FT-IR were used to characterize the catalysts. The results showed that: when active allocation ratio of the catalyst was Ru:Cu:Fe:Ce:La = 1:0.5:0.5:0.5:0.5, the degradation rate of methyl orange could reach up to 98.5%. And the concentration of each metal component eluted lower after the reaction, while its activity and stability were relatively high.The active component of 1wt% Ru catalyst mainly existed as the form of γ-Al2O3, RuO2, La2O3, La2CuO4 and CeO2. The surface of catalyst was relatively flat and flaky. The Ru catalyst appeared strong infrared absorption in the vicinity of 1070 cm-1, 1650 cm-1 and 3450 cm-1.
Research on the Change of Energy in the Process of the Micro Bubble Formation with Dissolved Air Method
Authors: Fan Yu Guang , Liu Zhao , Li Jing Ming , Zhou San Ping , Chen Bing , Lin Hong Xian
Published: March 2013

The generation method of dissolved gas micro bubble is introduced in the paper. The micro bubble producing process can be divided into two stages-nucleation and expansion through analysis. The formation process and the free energy change of the micro bubble is analyzed according to the homogeneous nucleation theory, free energy change formula of the two process is derived, and relation between bubble radius and formation bubble number under certain conditions is also discussed. It is concluded that the smaller the radius of formed bubbles, the more free energy change and initial energy are needed according to the analysis of the relation above.
The Analysis of Changsha Spatial Self-Organizing Mechanism in the Period of Republic of China
Authors: Lu Zheng , Zhou Xuan
Published: March 2013

As an inland city, the spatial form of Changsha has undergone its development for more than two thousand years. Extremely stable development of socio-economical culture made little influence on the form evolution of urban center in Feudal Age. However, from 1904 to 1949, frequent and obvious changes on city’s space configuration appeared along with the socio-economical revolution by reason of opening the port, and the characteristic of spatial replacement of downtown was also especially obvious. Therefore, changes of spatial configuration, as a reflection of free commercial economy after opening port, were studied in this paper to illustrator the self-organizing process of the city space evolution. With respect of studying method, space syntax theory was used to analyze and model the process of spatial organization rather than only using thus history or humanities perspective. After comparing syntactic measurement with five historical periods, the spatial features of self-organizing morphology present three rules: (a) self-similarity of morphological evolution, (b) synergy and disturbance relations by local-global spatial interaction and (c) city business center consistently located in the high integrated spaces. As a result, these rules of spatial self-organizing could be explained by a socio-physical phenomenon of single center configuration with today’s city expansion.
Acute Aquatic Toxicity of Brominated Flame Retardants Decabromodiphenyl Ether (decaBDE) on Scenedesmus obliqnus
Authors: Ye Jing , Xia Wei Hong , Lian Jia
Published: March 2013

In this study, the acute toxicity of brominated flame retardants decabromodiphenyl ether (decaBDE) on green alga Scenedesmus obliqnus has been investigated. Under laboratory conditions, low dosage of decaBDE (0.1, 0.2, 1, 5, 10 μg/L) can inhibit the growth of Scenedesmus obliqnus. The max inhibition rate was 27.39% by 10 μg/L decaBDE on day one. Chlorophyll contents were significantly inhibited by decaBDE. At the concentration of 10 μg/L, the inhibition rates of chlorophyll a and chlorophyll b were 68.1% and 86.0%, respectively. These results indicated that decaBDE pose toxicity on Scenedesmus obliqnus in the environment.
Study of Preparation, Characterization and Temperature-Programmed Reduction of NiO-ZnO Binary Materials
Authors: Tang Chih Wei , Hwang Jiunn Jer , Lin Shie Hsiung , Chung Chin Chun
Published: March 2013

The NiO-ZnO binary materials had been prepared by co-precipitation method. The weight percent of nickel of NiO-ZnO materials were 5, 10 and 20; they were pretreated under air at temperature of 300, 500 and 700°C, respectively. The characterization of NiO-ZnO materials were the thermal gravity analysis(TGA), X-ray diffraction(XRD), N2 adsorption-desorption at 77K, scaning electron microscope(SEM) and temperature-programmed reduction(TPR). The results revealed that surface areas of NiO-ZnO materials order from large to small were 20NiZn(OH)x(66 m2·g-1) > 10NiZn(OH)x(34 m2·g-1) > 5NiZn(OH)x(9 m2·g-1) after being calcined at the temperature of 500°C. Further, NiO-ZnO materials had two main reductive peaks at 390-415°C and 560-657°C, respectively. In all NiO-ZnO materials, 20NiZn(OH)x-C500 material had the highest surface area and the best interaction between NiO and ZnO.
Synthesis of Carbon-Sphere@TiO2/Cu Core-Shell Composites and the Studies on their Photocatalytic and Antibacterial Properties
Authors: Wang Hong Yan , Li Hong Liang , Liu Hui , Fu Ai Ping , Kan Guang Wei , Wang Qiao
Published: March 2013

Non-contacting (rattle-type) carbon-sphere@TiO2/Cu core-shell composites were prepared through the spray drying technique combined with calcinations using melamine formaldehyde (MF) microspheres as core templates, and TiO2colloid and cupric salt as shell precursors. After the calcination of the as-dried MF@TiO2/cupric salt core-shell spheres at elevated temperatures under nitrogen, rattle-type carbon-sphere@TiO2/Cu core-shell composites were derived with relative uniform sizes. Photocatalytic tests showed that the composites obtained at 550 °C exhibited higher efficiency than those obtained at 700 and 800°C and also higher than the P25 commercial TiO2for the degradation of methylene blue (MB) under visible light irradiation. Antibacterial studies revealed that the rattle-type composites owned excellent antibacterial ability and were stable and reusable.
Crushing Behavior of Hybrid Foam-Filled Pultruded Composite under Quasi-Static Oblique Loading
Authors: Abdullah S. , Arifin A.A. , Othman A. , Ariffin A.K. , Mohamed N.A.N.
Published: March 2013

In this present paper, the two square cross-section pultruded composite tubes E-glass reinforced polyester unfilled and polyurethane hybrid foam-filled subjected to oblique load are investigated and examined experimentally. The oblique angles were varied from 5 to 20 with an increment of every 5 degree. The bottom base platen of clamped specimen was adjusted inclination angle of loading direction with respect to the tube axis. During the experimental observation, three characteristic crushing stages were identified as initial peak load stage, progressive crushing stage and compaction zone stage. The pultruded composite tube wall-thicknesses of at 3 mm were examined, and the effects of crushing behaviors and failure modes were analyzed and discussed. Results showed that the tube’s energy absorption capability was affected significantly by varying of oblique loading. It is also found that as the filling polyurethane foam into pultruded E-glass reinforced polyester composite square tube increases the amount of specific absorbed energy than the empty tubes.
The Effect of Glycidyl Silane as Coupling Agent in Intumescent Flame Retardant System
Authors: Raden Siti Amirah Hambali , Mohd Ahmad Faiza , Yhaya Mohd Firdaus , Mohamed Rahmah , Nur Raihan Mohamed
Published: March 2013

The effect of different carbonizing agents; ethylene glycol, glycerol, and pentaerythritol to the char formation were studied in this research. After burning process, formulation with ethylene glycol, glycerol, and pentaerythritol showed chars thickness of 10 mm, 32 mm, and 45 mm. The chars’ strength at peak force was recorded at 3.20 N, 7.75 N, and 9.48 N while the burning rate of each sample were 5.23 x 10-4 mm/s, 4.20 x10-4 mm/s, and 6.24 x10-4 mm/s respectively. Formulation with glycerol as carbonizing agent showed the lowest burning rate as compared to the other formulations. Additional formulation with glycidyl silane as coupling agent in glycerol formulation was also studied. The formation of chemical bonding between silane, glycerol, and epoxy glycerol was confirmed by Fourier Transform Infrared (FTIR) absorption peak at 767.25 cm-1. The burning rate was 1.44 x 10-5 mm/s after silane treatment. Thermal degradation of the silane-treated resin started at 220°C as measured by thermogravimetric analysis (TGA).
Experimental Verification and Design of Glass-FRP Composite Grids
Authors: Melcher Jindrich , Karmazínová Marcela
Published: March 2013

Based on the research and design activities conducted at Brno University of Technology, Czech Republic this paper deals with the basic information on problems of the design and actual behaviour of selected FRP structural components for civil engineering. In particular, the recorded experimental studies are focused mainly on the design assessment of glass-fibre grid flooring components. The design criteria for structural FRP parts of load-carrying systems should verify especially the final displacements. Thus, in general, the ultimate limit state of structural system is not only the problem of ultimate strength but namely the problem of accordant final displacements. The analysis of test results gives data for verification of numerical modelling and of conventional design criteria. Considering the specific character of structural all-FRP systems, for the structural design the recognition of the deflection advancement can be decisive.
Optical Imaging and Display by Using Two Dimensional Photonic Crystals Slab
Authors: Liu Zhi Yong , Huang Rui Qiang
Published: March 2013

We numerically investigate the imaging properties of the two dimensional square photonic crystal. It is found that the dependence of the image-to-interface distance on the object-to-interface distance is almost linear. We can manipulate the near field location of the image through the object-to-interface distance. When the object is located 1μm away from the interface, the image locates at the output interface which can be used to realize the near field optical display.
A Nanosilver Resonance Rayleigh Scattering Method for the Determination of Trace Cysteine
Authors: Zhang Xin Hui , Wei Yan Yan , Zhang Chi , Chi Miao Miao , Zhang Jian , Liang Ai Hui
Published: March 2013

Using PEG-10000 and sodium citrate as stabilizer, and NaBH4 as reducer, a stable nanosilver (AgNPs) sol was prepared. In pH 6.6 phosphate buffer solution containing NaCl, the AgNPs were aggregated to large particles, which lead to resonance Rayleigh scattering (RRS) peak at 350 nm enhancement. Upon addition of cysteine, the peak decreased. The decreased value ΔI is linear to cysteine concentration in the range of 5.0×10-8-6.0×10-7 mol/L. Thus, a new RRS method was proposed for detection of cysteine.
Simulation and Optimization Research of Multi-Stud Tensioning Machine Controlled by Servo Valve
Authors: Tan Xiao Dong , Ji Wei , Luan Zhi Bo
Published: March 2013

In this paper, we base on the simulation analysis of the electro-hydraulic servo system about dual hydraulic cylinders parallel driving Multi-Stud Tensioning Machine, focus on the dynamic characteristics of a single hydraulic cylinder (asymmetric hydraulic cylinder), make use of Matlab Simulink module to carry on to imitate, and design a PID controller to correct the system. The results of simulation prove correctness of the system mathematic model, and the stability of the system is obviously improved.
Improvement of Air Supply Pressure Product Calibration Model
Authors: Li Tao , Li Xiao Chen , Chen Li , Zhang Ning
Published: March 2013

The current situation of air supply pressure product verification of the air-to-air missile equipment is analyzed in air force, the existing problems of the mode operation, the actual implementation and other aspects are pointed out, suggestion for improvement is put forward, and a preliminary scheme of the calibration equipment is given.
Present Situation of Research on Coal Mining Subsidence under Highway in China
Authors: Deng Wei Nan , Zhang Hua Xing
Published: March 2013

Research on coal mining subsidence under highway can be divided into two fields: research on the problems caused by coal mining under highway and research on the problems caused by highway construction above mined-out area of coal mine.The issues about safety，design and engineering are the key points restricting the safety and the construction of highway in coal mining areas. The paper completely summarized and analysed the present situation of research on coal mining subsidence under highway and the special characteristics comparing with the general building and the railway. In order to ensure the safety of existing highways and highways in planning in coal mining areas, according to the deficiency of current research, this paper put forward the future research directions of coal mining subsidence under highway.
Diagnosis and Transformation of Air Conditioning and Refrigeration System for a Shopping Mall
Authors: Zhu Cai Xia , Zhao Xiu Yong , Yang Rui Liang , Xu Zi Long
Published: March 2013

The problem of air conditioning and refrigeration system for a shopping mall is diagnosed in detail. Subsequently, transformation of air conditioning and refrigeration system is carried out. One-time investment, operating costs and payback period of this transformation is analyzed in detail. Result of this transformation shows this transformation is more successful.
Numerical Simulation of Gradient Heat Treatment Process of Cylinder Welding Component of 30Si2MnCrMoV Steel
Authors: Wang Q. , Gu W.L. , Sun D.L. , Han X.L. , Xue M.Y.
Published: March 2013

The finite element analysis method was applied to simulate the gradient field heat treatment process of a cylinder welding component of 30Si2MnCrMoV steel by software ANSYS. In the heat treatment process，the distribution of temperature field, the variation curve of residual stress with time，the distribution of residual stress along the axial direction of cylinder, and the axial and radial deformation of the specimen were calculated and the influences of partial heating area on the distribution of temperature and residual stress were analyzed. The calculating results show that the temperature in the weld metal zone and heat affected zone of welding specimens may exceed the phase transformation points during the gradient heat temperature. The residual stress and the radial deformation in the weld metal zone were greater than those in the matrix zone. The final deformation of specimen was along the axial direction. With the increase of partial heating area, the phase transformation area was increased and the residual stress was reduced effectively.
MoSe2/Polypyrrole Solar Cell
Authors: Shukla S.P. , Patel Haresh S. , Patel K.D. , Pathak V.M.
Published: March 2013

MoS possesses a band gap around 1.4 eV which is nearly to maxima of solar radiations. The investigations on this kind MoSbased photovoltaic cells having the rectifying interface with polypyrrole. It was observed that MoS/polypyrrole structure exhibits a photovoltaic behaviour. The photoconversion efficiency and fill factor of above cell is calculated, the maximum photoconversion efficiency is 0.089 and fill factor is 0.5.
Concentration Depended Thermodynamic Properties of Fe-Co Liquid Binary Alloy
Authors: Sonvane Y.A. , Patel J.J. , Thakor Pankajsinh B. , Gajjar P.N. , Jani Ashvin R.
Published: March 2013

The thermodynamic properties like heat of mixing (ΔE), entropy of mixing (ΔS) and volume of mixing (ΔΩ) of Fe-Co liquid binary alloys are computed using our newly constructed parameter free model potential. We have also attempted to investigate the effect of various forms of exchange and correlation functions, namely, Hartree (H) and Taylor (T) on the thermodynamic properties of Fe-Co liquid binary alloys. It is found that the proper choice of the model potential along with the local field correction function play an important role in investigating the thermodynamic properties of Fe-Co liquid binary alloys.
Concentration Dependent Physical Properties of SiSn Solid Solution
Authors: Jivani A.R. , Jani Ashvin R.
Published: March 2013

In the present investigation, we report theoretical study of total energy, energy band gap in X-direction, bulk modulus, elastic constants and pressure derivative of elastic constants of Si1-xSnxsolid solution using higher-order perturbation theory along with application of our proposed potential, where x is concentration of Sn. The parameter of our potential is determined using zero-pressure equilibrium condition. In the present calculations, The local-field correction function can be employed to consider exchange and correlation effects. The present study showed that the physical quantities under investigation varied with the concentration of the constituent element.
Formulation of Dielectric Behaviour of Composite Material
Authors: Banerjee Ananya , Sarkar Aditi , Sarkar A.
Published: March 2013

A simple formula for effective dielectric constant of composite material or DMD is proposed. In case of magnetic element in the composite the effect of magnetic susceptibility is taken into account to describe the dielectric behavior. A theoretical formulation of the proposed dielectric function along with an experimental result is presented here. The overall results are found to be good and consistent .
Mn-Doped ZnO Micro and Nanocrytals: Synthesis, Characterization and Properties
Authors: Sharma Rakesh Kumar , Patel Sandeep , Pargaien Kamlesh Chandra
Published: March 2013

The development of highly sensitive, selective, reliable, low power and compact sensing devices to detect gas is of major importance for terrestrial and space applications. The gas response to different gases and chemicals is related to a great extent to the surface state and morphology of the materials. Zinc oxide (ZnO) is a direct wide band gap semiconductor with an energy gap of ~3.37 eV and a large exciton binding energy of ~60 meV at room temperature (RT) is a promising candidate for functional component for devices and materials in chemical and gas sensors and so on. ZnO nanostructures with various interesting structures and properties have been synthesized, such as nanoparticles, nanorods, nanobelts, nanocombs, nanowires, tetrapod nanostructures. Mn-doped hexagonal (ZnO) semiconductor micro and nanostructures have been synthesized by a simple one-step aqueous solution method at relatively low temperature. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and photoluminescence spectroscopy (PL) have been used to characterize the samples in detail. The XRD studies revealed that Mn doped ZnO micro and nanostructures had wurtzite structure (hexagonal). The as-synthesized ZnO micro and nanostructures consist of very uniform and no secondary phase is observed. X-ray diffraction and EDX results provide the evidence that Mn is incorporated into the ZnO crystals. A strong and wide ultraviolet emission has been observed for the Mn doped ZnO micro and nanocrystals as evidenced by the photoluminescence spectra at room temperature.PL spectra reveals that as synthesized samples are highly pure and crystalline. Magnetism in these samples was also studied by using vibrating sample magnetometer.
Magnetic Compton Scattering Study of Ni2Mn1.4Sn0.6 Shape Memory Alloy
Authors: Dashora Alpa , Mund H.S. , Sahariya J. , Priolkar K.R. , Lobo N. , Itou M. , Sakurai Y. , Ahuja B.L.
Published: March 2013

Spin momentum density in Ni2Mn1.4Sn0.6 shape memory alloy has been measured using magnetic Compton scattering technique. The experiment has been performed using 182 keV circularly polarized synchrotron radiation at temperature 10 K at SPring-8, Japan. Experimental magnetic Compton profile has been decomposed to determine the site specific magnetic moments, where the magnetic moment at Mn site was found to be dominating. It is seen that the total spin moment in present non-stoichiometric alloy is smaller than that of stoichiometric Ni2MnSn.
Refractive Index Engineering of Ar+ Implanted CR-39 Polymer
Authors: Shekhawat Nidhi , Sharma Annu , Aggarwal Sanjeev , Nair K.G.M.
Published: March 2013

The effects of argon ion implantation on the structure and refractive index of CR-39 polymer has been investigated. CR-39 specimens were implanted with 130 keV argon ions in the fluence range of 5×1014-1×1016 ions cm-2. The structural changes produced as an effect of implantation has been studied using specular reflectance Fourier transform infrared spectroscopic technique. The absorption and specular reflectance spectra in the visible region of these specimens has been recorded by using UV-Visible spectroscopic technique. The extinction coefficient has been measured using the absorption coefficient values calculated from absorption spectra. Utilizing the values of extinction coefficient and reflectance, the refractive index of virgin and implanted specimens has been calculated. Significant enhancement in the refractive indices of implanted specimens has been observed. These changes in the values of refractive index have been further correlated with the hydrogen depleted graphitelike structures formed on the surface of implanted specimens as evidenced from specular reflectance FTIR technique. The potential of forming planar waveguides using these implanted specimens has been explored.
Half-Metallic Ferromagnetism in MgS by Doping with Sp-Element: A First-Principles Calculations
Authors: Yogeswari Moovendran , Umamaheswari Rajagopalan , Kalpana G.
Published: March 2013

The first-principles calculations using full potential linearized augmented plane wave method (FP-LAPW) was performed to determine the influence of dopants (N, P, As and Sb) on the electronic structure of MgS in the rock salt structure. In the present work both local spin density approximation (LSDA) and generalized gradient approximation (GGA) were used for exchange correlation potential functional. Among the group V elements N-doping alone induce half-metallic ferromagnetism in MgS host with a magnetic moment of 1.00 μB/f.u. Total energy calculations show that ferromagnetic state is more stable than non-magnetic state in all the compounds. The ground state properties such as equilibrium lattice constant, bulk modulus and bond length were calculated. The spin polarized electronic band structure, total and partial density of states calculations were carried out to study the origin of half-metallic ferromagnetism in these compounds. The difference between two exchange-correlation functions is also analyzed.
Structural and Optical Characterization of Zinc Telluride Thin Films
Authors: Rathod J.R. , Patel Haresh S. , Patel K.D. , Pathak V.M.
Published: March 2013

Group II-VI compounds have been investigated largely in last two decades due to their interesting optoelectronic properties. ZnTe, a member of this family, possesses a bandgap around 2.26eV. This material is now a day investigated in thin film form due to its potential towards various viable applications. In this paper, the authors report their investigations on the preparation of ZnTe thin films using vacuum evaporation technique and their structural and optical characterizations. The structural characterization, carried out using an X-ray diffraction (XRD) technique shows that ZnTe used in present case possesses a cubic structure. Using the same data, the micro strain and dislocation density were evaluated and found to be around 1.465×10-3lines-m2and 1.639×1015lines/m2respecctively. The optical characterization carried out in UV-VIS-NIR region reveals the fact that band gap of ZnTe is around 2.2eV in present case. In addition to this, it was observed that the value of bandgap decreases as the thickness of films increases. The direct transitions of the carries are involved in ZnTe. Using the data of UV-VIS-NIR spectroscopy, the transmission coefficient and extinction coefficient were also calculated for ZnTe thin films. Besides, the variation of extinction coefficient with wavelength has also been discussed here.
Study on CdSe Nanoparticles Synthesized by Chemical Method
Authors: Deshpande M.P. , Garg Nitya , Bhatt Sandip V. , Soni Bindiya , Chaki Sunil H.
Published: March 2013

CdSe is a II-VI group semiconducting material with optimum bulk band gap of 1.74eV. It is a promising material due to its wide range of technological applications in optoelectronics devices. CdSe nanoparticles have been synthesized at different temperatures starting from Room temperature to 80°C using appropriate precursor solutions containing Cadmium acetate, Triethanolamine (TEA), Ammonia and Sodium selenosulphate. The pH of Solution was around 10.50 ± 0.10 during synthesis. We confirmed the elemental analysis by Energy Dispersive X-ray Analysis (EDAX) and X-ray Photoelectron Spectroscopy (XPS) technique. X-Ray Diffraction (XRD) studies shows that the synthesized nanoparticles belonged to cubic phase with crystallite size lying between 2nm-4nm. The effect of temperature on particle size, lattice parameter, density of dislocation and strain were investigated. Blue shift of 103nm to125nm has been observed from optical absorption spectra and raman measurements performed at room temperature using He-Ne laser (632nm, 5mW) showed the presence of longitudinal optical phonon modes. Photoluminescence (PL) studies shows a shift of 30nm when compared with the bulk PL emission peak.
Characterization of SnSePb0.1 Thin Films Deposited by Flash Evaporation Technique
Authors: Pathak Vishal N. , Mistry Prashant , Patel Mayur , Hingarajiya Keyur S. , Solaki G.K. , Pathak V.M. , Patel K.D.
Published: March 2013

Tin Selenide compounds have attracted considerable attention because of their important properties useful for optoelectronics, holographic recording systems, electronic switching and infrared production and detection. Moreover, SnSe is a semiconductor with a band gap of about 1 eV that makes it potential candidate for solar cell material. Further, the optoelectronic properties of SnSe can be modified using doping of lead, copper etc. In this context, we report here results of the preparation and characterization of flash evaporated lead doped SnSe thin films. Thin films of SnSePb0.1having thickness of 100nm and 500nm were deposited on to chemically cleaned glass substrates. The chemical composition of the deposited SnSePb0.1thin films has been evaluated using EDAX technique. The structure of SnSePb0.1was studied using low angle XRD and it shows that the deposited films are polycrystalline in nature having orthorhombic structure. Various lattice parameters along with micro strain for both 100nm and 500nm thin films have been evaluated. Electrical transport properties have been also investigated using high temperature Hall Effect measurement in the temperature range 300 400K. The decrease in the resistivity of deposited films with increasing temperature confirms the semiconducting behavior of SnSePb0.1thin films.
Preparation and Characterization of Polymer Blends of Ethyl Cellulose and its Composites
Authors: Nivrtirao Eknath , Sannakki Basavaraja
Published: March 2013

The polymer blend of Ethyl Cellulose (EC) with Poly (vinyl) pyrrolidone (PVP) of various weight percentages at different thickness are used for measurement of dielectric permittivity, electrical conductivity and optical properties. The activation energies of the EC and its blend with PVP are obtained through measurement of dc conductivity. The samples are characterized by using X-ray diffractometer (XRD). The blends of EC with PVP in the ratio of 50:50 weight percent using FTIR over the range of wavenumber 4000-500 cm-1. Key words: Polymer Blend, XRD, SEM, FTIR, dielectric permittivity, activation energy.
Synthesis, Structural and Optical Characterization of PVA Capped Cadmium Sulphide Nanocrystalline Films by Chemical Bath Deposition Method
Authors: Devi L. Sujata , Devi K. Nomita , Sharma B. Indrajit , Sarma H. Nandakumar
Published: March 2013

Nanocrystalline CdS thin films were deposited on glass substrate by chemical bath deposition method using Cadmium Sulphate and Thiourea as Cd+2and S-2ion sources for different molarities i.e. 0.1 M, 0.2 M and 0.3 M. The crystallite size and lattice parameters for each sample were determined from X-Ray diffraction data using Scherrers formula. The value of the crystallite size was found to be within the range 14.7 nm-11.4 nm. The optical characterization was done by UV-Visible and photoluminescence spectroscopy. The optical band gap of the films was determined from the transmittance spectra. It was observed that when the molarity increases, the average crystallite size decreases and the band gap energy of the prepared films increases. Photoluminescence studies showed a prominent peak at around 530 nm. The radius of the nanocrystalline films had been evaluated from the absorption spectrum by using effective mass approximation formula.
Structural and Optical Characterization of Tungsten Diselenide Crystals Grown by DVT Technique
Authors: Patel P.R. , Rathod J.R. , Patel Haresh S. , Patel K.D. , Pathak V.M.
Published: March 2013

WSe2 is a member of groupVI Transition Metal Dichalcogenides (TMDCs) and has been observed to be a highly stable semiconducting material. It has been grown in crystal form using a direct vapour transport technique in present case. The grown WSe2 crystals were characterized for the structural properties using X-ray diffraction technique (XRD). The hexagonal structure was confirmed through this analysis. Using the data of XRD, various parameters like crystalline size, lattice parameters, micro strain, dislocation density, unit cell volume, unit cell density, growth fault and deformation fault probability etc were found. It was seen that the micro strain, dislocation density and growth & deformation fault probabilities were found to be very low in WSe2 crystals. The grown WSe2 crystals were characterized for optical properties using UV-VIS-NIR spectroscopy. The absorption spectra of WSe2 grown in present case revealed the fact that WSe2 posses direct band gap around 1.38eV. Layered di-chalcogenides WSe2 (or MoSe2) are used for desired applications such as in photo-conversion devices.
Effect of Temperature on Structural and Optical Properties of Chemically Deposited Tin Sulfide Thin Films Suitable for Photovoltaic Structures
Authors: Patel T.H.
Published: March 2013

SnS (tin sulphide) is of interest for use as an absorber layer and the wider energy band gap phases e.g. SnS2, Sn2S3and Sn/S/O alloys of interest as Cd-free buffer layers for use in thin film solar cells. Thin films of tin sulphide have been deposited using CBD at three different bath temperatures (27, 35 and 45 °C) onto microscope glass substrates. The X ray diffraction (XRD) analysis of the deposited films reveled that all films has orthorhombic SnS phase as dominant one with preferred orientations along (111) direction. The temperature influence on the crystalline nature and the presence of other phases of SnS has been observed. The average grain size in the films determined from Scherers formula as well as from Williamson-Hall-plot method agrees well with each other. Energy dispersive X-ray (EDAX) analysis used to determine the film composition suggested that films are almost stoichiometric. The scanning electron microscopy (SEM) reveals that deposited films are pinhole free and consists of uniformly distributed spherical grains. The optical analysis in the 200-1200 nm range suggests that direct allowed transitions are dominant in the absorption process in the films with variation in the band gap (~1.79 to ~2.05 eV) due to variation in deposition temperature.
Preparation and Modification of Carbon Blacks from Wastes
Authors: Zhang Bao Hua , Tan Hui Jie , Suo Hui Hui , Li Hong Da , Wan A Jun
Published: March 2013

It is one of the focuses of the world today to save resources and avoid pollutions by waste recycling and reusing. Pyrolysis of rubbers, plastics and plants is an economical and reliable method of recycling to produce carbon blacks and other products. But the carbon blacks are useless before modification. This paper summarizes the preparation and modification of carbon blacks from wastes. The modification methods of carbon black include removing impurities and improving the surface activities. A lot of application examples were given here.
The New Technologies in Chitin/Chitosan Preparation
Authors: Yang Shou Feng , Zhang Hong Cai , Shi Yi Xiang , Wan A Jun
Published: March 2013

Chitin/chitosan, a naturally renewable resource, have unique functional properties including biocompatibility, biodegradability, and non-toxicity, which have been widely applied in many fields, such as food, agriculture, medicine, materials, etc. Chemical method is commonly employed in extracting chitin/chitosan in China, but that requires significant amount of waste, and will seriously pollutes the ecological environment. Recently, studies in extracting chitin/chitosan using environment-friendly methods are substantially reported at home and abroad. The aim of this paper is to review the latest research development of extraction methods of chitin/chitosan from raw materials, providing helpful guidances for researchers in this field.
The Latest Applications of Chitin and Chitosan in Wastewater Treatment
Authors: Yang Shou Feng , Zhang Hong Cai , Shi Yi Xiang , Wan A Jun
Published: March 2013

Chitosan has multiple applications due to its advantages including availability, biocompatibility and biodegradability in food, agriculture, material science and so on. In recent years, chitosan was frequently chosen as absorbent of wastewater and reached a satisfactory effect. It should be noted that it is one of most important links in the environment enhancement chains using chitosan as absorbent of heavy metal in wastewater treatment. Chitosan-molecularly imprinted polymers with favorable absorption ability can meanwhile absorb many heavy metal including Cu2+, Hg+, Mn2+ion, etc. The aim of this paper is to review their latest development in wastewater treatment for providing helpful guidances for researcher in this field.
Effect of Synthetic Wastewater by Electrochemical Pretreatment on Chlorella vulgaris Growth and Nutrients Removal
Authors: Wang Meng Zi , Zhu Zhi Wei , Cao Wei , Zhou Hong De , Wu Yu , Li Bao Ming , Zhang Yuan Hui
Published: March 2013

Electrochemical processing combined with the system of microalgaeChlorella vulgariswas used to treat the synthetic organic wastewater in this paper. The effect of wastewater concentration on the biomass growth and nutrients removal was investigated. Three levels of the wastewater concentrations were ranked as Low, Mid and High, respectively. After 2 h of electrolysis pretreatment and 10 d of microalgae cultivation, TOC, NH4-N, and TP concentrations in the group Low were reduced by 83.7%, 99.3% and 95.0%, respectively. TheChlorella vulgarisin the groups Mid and High without electrolysis pretreatment did not survive longer than 24 h, whereas it grown well in the wastewater pretreated by electrolysis. The dry weight (DW) ofChlorella vulgarisin the group Low with electrolysis pretreatment was increased from 0.048 g/l to 1.087 g/l by 10 d cultivation. Results indicate that electrolysis pretreatment for wastewater can provide appropriate conditions for the subsequent biological treatment and efficiently promote the biomass growth ofChlorella vulgaris.
Fermentation of Lignocellulosic Wastes for Volatile Fatty Acids at Different Temperatures under Alkaline Condition
Authors: Li Ling , Wen Yue , Xu Chao , Wang Li Hui , Zhou Qi
Published: March 2013

In this work, the hydrolysis and acidification of lignocellulosic wastes for volatile fatty acids at different temperatures (10°C~55°C) under strong alkaline condition of pH12 in the anaerobic digestion process of wetland plant litter (WPL) were investigated. The variation of organic carbon sources, sugar and VFAs was examined and the carbon source balance was analyzed during the above process. The results showed that the hydrolysis of WPL was enhanced under strong alkaline condition of pH=12 and the hydrolysis of WPL was accelerated as the temperature increased. The SCOD concentrations in the fermentation liquid increased constantly with temperature, but the percentage of the other carbon that microbe utilized difficultly in SCOD was as high as 45%~69%. Acetic acid was the most dominant VFA. At 25°C, the accumulation of VFAs reached the maximum value of 93mgCOD/g biomass on the 20thd. Twenty-five degrees Celsius could be considered as the optimal conditions for VFAs accumulation at pH=12 in this study as both the quantity and quality of the carbon sources achieved a higher level.
Atomic Force Microscope (AFM) Studies of TiO2 Nanocoated Glass Surface via Sol-Gel Coating
Authors: Achoi M.F. , Asiah Mohd Nor , Rusop Mohamad , Abdullah Saifollah
Published: March 2013

Atomic Force Microscope (AFM) has been used to study the surface properties of TiO2 nanocoated glass surface at atomic level. TiO2 nanocoated glass surface was prepared by synthesis of titanium butoxide (TTiB) as precursor and was then deposited on glass surface via spin-coating technique. The AFM details studied of TiO2 nanocoated glass surface revealed that the nanoparticle was uniformly distributed throughout glass surface with growth of TiO2 nanostructures below 12 nm via AFM surface morphology and topography characterization, respectively. It was also showed that the cross-sectional view analysis is 5.22 nm and surface roughness, Ra, of coating is 0.858 nm, respectively. The TiO2 nanostructures were successfully seen grew at 0.2 M of sol-gel solution. It confirmed that for the coating application at nanometer scale level on the glass-based material equipment.
Carbon Nanotubes in Cancer Treatment: A Preliminary In Vitro Study Using Neuroblastoma Cells
Authors: Nurulhuda Ismail , Mazatulikhma Mat Zain , Poh R. , Rusop Mohamad
Published: March 2013

Carbon nanotubes (CNTs) were reported to cause severe toxicity in in vivo and in vitro studies. On the other hand, CNTs has the potential as a mechanism for drug delivery across the blood brain barrier due to its nano-sized dimensions. The present preliminary study examined the cytotoxic effect of CNTs in serum-free and serum-containing EMEM medium on neuroblastoma cells growth. The MTS assay showed that CNTs did not cause any cytotoxicity at concentrations below 0.1 mg/mL at 24 and 48 h incubation in serum-containing EMEM medium. This finding suggested that below 0.1 mg/mL, CNTs can be used as a mechanism for drug delivery for the treatment of neuronal cancer. However, CNTs showed slighty toxic towards neuroblastoma cells at concentration 0.1 mg/ml at 48h incubation in serum-free EMEM medium. This finding indicates that the present of serum play a role for toxicity effect of CNTs in cells.
Electroluminescence and Photoluminescence Properties of Porous Silicon Nanostructures with Optimum Current Density of Photo-Electrochemical Anodisation
Authors: Zubaidah M. Ain , Fadzilah Suhaimi Mohd Husairi , Yusop S.F.M. , Asnida Noor Asli , Rusop Mohamad , Abdullah Saifollah
Published: March 2013

P-type silicon wafer ( orientation; boron doping; 0.75 ~ 10 Ω cm-1) was used to prepare samples of porous silicon nanostructures (PSiNs). All samples have been prepared by using photo-electrochemical anodisation. A fixed etching time of 30 minutes and volume ratio of electrolyte, hydrofluoric acid 48% (HF48%) and absolute ethanol (C2H5OH), 1:1 were used for various current densities, J. There were sample A (J=10 mA/cm2), sample B (J=20 mA/cm2), sample C (J=30 mA/cm2), sample D (J=40 mA/cm2) and sample E (J=50 mA/cm2). Photoluminescence (PL) and electroluminescence (EL) spectra were investigated. Maximum peak position of PL spectrum at about ~675 nm, while the maximum EL spectrum at about ~650 nm (which is similar to the PL spectrum).
Synthesis and Characterization of Carbon Nanotubes from Palm Oil by Aerosol-Assisted CVD
Authors: Maryam M. , Abu Bakar Suriani , Shamsudin M.S. , Rusop Mahmood Mohamad
Published: March 2013

This paper will report on the synthesis of bundles of aligned single wall carbon nanotubes (SWCNTs) and multiwall carbon nanotubes (MWCNTs) from palm oil precursor and ferrocene as catalyst source by two stage aerosol-assisted CVD system at various deposition temperature ranging from 700-900oC. Palm oil was pyrolised into the furnace which contained the catalyst source producing black substances at the wall of the reaction furnace which were then collected to be characterized. Field emission scanning electron microscopy equipped with energy dispersive X-ray was used to obtain weight percentage, identification of samples and image of CNTs which showed different structures and diameters of CNTs relative to the deposition temperature of furnace. Raman Spectroscopy was used to further study the quality and identification of samples and finally X-ray powder diffraction was used to determine the crystalinity of samples. Individual micrograph of MWNTs at optimized deposition temperature was also obtained from the high resolution transmission electron microscopy.
Synthesis of β-Silicon Carbide Nanowires by a Simple, Catalyst-Free Carbo-Thermal Evaporation Technique
Authors: Al-Ruqeishi Majid S. , Md Nor Roslan , Mohd Amin Yusoff , Al-Azri Khalifa
Published: March 2013

β-SiC nanowires were successfully fabricated on pare Si (100) substrate using simple carbo-thermal evaporation of graphite at 1200°C. The obtained β-SiC nanowires were aligned with diameters ranged between 40 to 500 nm. The majority of crystal planes were β-SiC (111) with other less intensity of (200), (220) and (311). The silicon substrate location inside the furnace found to be critical in the formation of the β-SiC nanowires. Also, FTIR absorption peaks for β-SiC nanowires found at higher frequency side of 1110 cm-1 which is pointed to Si–O asymmetric stretching mode.
Impact of Nanopowders on Exraction Yield of Centella asiatica
Authors: Borhan M.Z. , Ahmad R. , Rusop Mohamad , Abdullah Saifollah
Published: March 2013

Centella asiatica (C. Asiatica) is a traditional herb that has been used in raditional medicine especially in Asia region. Recently the pharmalogical study of Asiatic acid (AA) which is one of bioactive constituents in C. Asiatica has been studied and revealed that this compound has a potential to be use in medicine area. The objective of this paper is to produce nanoparticles C. Asiatica by Planetary Ball Mill (PBM) and determined the effect of nanonization on extraction yield of asiatic acid. The particles were analyzed using particle sizer to determine size of particle produce and the morphology was evaluated through FESEM. As a result, the mean particles size of nanopowders was 501.10 nm and the extraction of asiatic acid using nanopowders showed 82.09 % higher than original powder.
Properties of Iodine Doped Amorphous Carbon Thin Films Grown by Thermal CVD
Authors: Kamaruzaman Dayana , Fadzilah A.N. , Ishak A. , Rusop Mahmood Mohamad
Published: March 2013

Thin film of undoped and doped amorphous carbon has been achieved using the simple thermal CVD system in an ambient gas of Ar and Ar with I2, respectively. The electrical and optical properties of the iodine doped amorphous carbon (a-C:I) thin films were studied. The incorporation of iodine into the amorphous carbon thin film results in increase of electrical conductivity as doping temperature increase up to 400°C, which indicates that doping effect of iodine. Heterojuction is confirmed by rectifying current-voltage characteristics of a-C:I/n-Si junction. The decreasing of optical band gap from 0.54 to 0.25 eV after iodine doping was determined which contribute to induce graphitization in the films. Raman result indicates that sp2 and sp3 bonded carbon atoms were dominated in the both with and without iodine doped thin films.
A Review on Zinc Oxide Nanostructures: Doping and Gas Sensing
Authors: Abdullah Nurul Afaah , Khusaimi Zuraida , Rusop Mohamad
Published: March 2013

This paper presents a review on synthesis, structure, and growth mechanisms of one-dimensional nanostructures of ZnO. Solution-based method is a potential deposition technique for large-scale production as its advantages; the low cost, the simplicity of experimental set-up, and the low operating temperature. Mist-atomiser technique is one of the solution-based methods in synthesizing optimized ZnO nanostructures. Doping will lead for better properties of ZnO, which result to wide application area. Nanostructured ZnO is important in promising areas of application which devices utilizing nanostructures such as gas sensors and solar cells, since it is fairly easy to fabricate such forms of ZnO nanostructures, which have good charge carrier transport properties and high crystalline quality.
Growth of Self-Catalyzed ZnO Heterostructures Using Thermal Chemical Vapor Deposition Method
Authors: Shariffudin Shafinaz , Mamat Mohamad Hafiz , Rusop Mahmood Mohamad
Published: March 2013

ZnO heterostructures have been successfully synthesized using thermal chemical vapor deposition method. Zinc powder and oxygen were used as the starting materials, while argon gas was supplied as the carrier gas. Different types of nanostructures were deposited on layer-by-layer ZnO seeded catalyst; which its structures depended on the position of the substrates during the deposition process. Substrates at position C which is located 3 cm from the source shows uniformly distributed ZnO nanorods. XRD pattern also shows that sample C shows (0 0 2) diffraction peak. PL spectra indicates that the ZnO have two peaks, which is UV peak centered at 380 nm and visible peak centered at about 550 nm.