bluuebunny/crossref_metadata_2025 huggingface dataset:
Cost Savings in the Cast House through Optimizing Furnace Operation, Staff Training and Associated Variables
Authors: Grayson James T.
Published: August 2011

While it is generally acknowledged in our industry that people are the most important asset, the importance of technical training for furnace operators is often overlooked. The primary focus for training is often on the down stream process where the final product is either being cast or fabricated. The furnace operators have a key role since they have direct influence on factors that dramatically govern a range of costs factors which include: productivity; melt loss; metal content in the dross; energy usage, and metal cleanliness.
A Historical Perspective on Dross Processing
Authors: Peterson Ray D.
Published: August 2011

As long as aluminum has been manufactured and melted, various by-products with a mixture of aluminum and aluminum oxide have existed. The general name for this class of materials has historically been called “dross”. Within the larger family of drosses, there are a number of subclasses which we will explore. Unfortunately, the presence of even minor amounts of oxide in aluminum metal, render it useless for most structural applications. To be of value the aluminum metal must be free of oxides. Additionally, the inherently high value of the metal has driven innovation in methods to effectively and economically separate the metallic values from this mixture. This paper will present background information on the formation of drosses and the historical methods used to process the drosses.
3D Thermo-Mechanical Modelling of Wheel and Belt Continuous Casting
Authors: Grandfield John F. , Dablement Sébastien , Fjær Hallvard Gustav , Mortensen Dag , Lee Michael , Nguyen Vu , Savage Gary
Published: August 2011

Wire rod is produced by hot-rolling a bar of metal coming from a wheel/belt continuous casting process. This kind of process, e.g. Properzi, is an elaborate process in which the molten metal is poured in a cooled rotating mould formed by the groove of a wheel and closed by a belt. In order to better understand the heat transfer phenomenon and solidified bar characteristics, depending on process parameters a three dimensional thermo-mechanical model has been developed. The model, based on the finite-element method, calculates the heat transfer coefficient of the air gap at the metal-mould interface as a function of the size of the gap determined by the bar contraction and wheel and belt thermal deformations. The air gap formation due to metal shrinkage and mould deformation is the main factor which determines the heat extraction. Wheel temperature measurements with thermocouple and belt temperature measurements with an infrared system were carried out to verify model results. Attempts were also made to measure a liquid pool profile using doping with copper rich alloy. The model shows the effect of the casting temperature and the rotation speed on the air gap formation and resulting temperature and stress fields. The model can be applied to issues such as maximising wheel and belt life and minimising solidification defects.
The Approach to Zero Waste from Smelter and Secondary Dross Processing
Authors: Roth David J.
Published: August 2011

Worldwide production of aluminium continues to grow even in the past economic slowdown period, at present the annual production is at approximately 65 million metric tons per annum. The production of aluminum has contributed to about 1% of global green house gases and all industry is under pressure to reduce these emissions. The industry is also responsible for 1.0 – 1.8 million tons of dross/salt slag landfill waste per year. The percentage of aluminum recycled, (currently about one third), continues to increase and may be looked upon as a cornerstone for the reduction of green house gases in aluminum processing. Recycled aluminum needs just 5% of the energy and emits only 5% of green house gases but the re-melting of scrap aluminum produces dross that presents its own environmental problems.
Design of Secondary Alloy Compositions for High Performance Aluminium Pressure Diecastings
Authors: Lumley Roger
Published: August 2011

High pressure die-casting (HPDC) is a widely used production technique for metal components that are required to have close dimensional tolerances and smooth surface finishes. Approximately 50% of the aluminium castings produced globally are manufactured by HPDC from secondary alloy and these are dominant in the automotive sector where they account for the majority of aluminium components present in each vehicle manufactured. Recently, it has been shown that industrially produced aluminium alloy high pressure diecastings (HPDC’s) can be successfully heat treated without encountering problems with surface blistering or dimensional instability. These processes may significantly improve the properties which develop from the alloys, thereby significantly increasing the scope of applications that may be realized. HPDC alloys however have not been developed specifically for heat treatment or the optimization of specific properties. In particular, recent work in Al-Si-Cu HPDC alloys has identified composition ranges of alloys for a) achieving yield strengths exceeding 400 MPa, b), rapid heat treatment that minimizes cost / cycle times, and c) high strength combined with elevated ductility levels. The role of alloying elements, composition limits and effects on mechanical property development are discussed.
Effect of Homogenisation Parameters on Dissolution and Precipitation in Aluminium Alloy AA7150
Authors: Wang Li Juan , Xu Dao Kui , Rometsch Paul A. , Gao Sam X. , Zhang Yong , He Zheng Bo , Couper Malcolm J. , Muddle Barry C.
Published: August 2011

The thermal stability of constituent particles in both as-cast and homogenised alloy AA7150 has been investigated by means of scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The results indicate that the as-cast eutectic starts to melt at 474°C and that the melting onset temperatures of the η- and S-phase particles after homogenisation are 474°C and 484°C, respectively. Two types of homogenisation treatments were used to dissolve eutectic particles: a two-step homogenisation treatment (40 h at 465°C + 4 h at 480°C) can completely dissolve the η- and S-based constituents, whereas a significant amount of S-phase still exists after a single-step homogenisation treatment of 40 h at 465°C. After utilising the two-step homogenisation treatment to dissolve all the η- and S-based constituents without overheating, samples were cooled at different controlled cooling rates and analysed by SEM and DSC to understand the effect of cooling rate on the type, size, distribution and density of precipitates formed during the cooling process. Slow cooling was found to result in the precipitation of coarse η-phase particles, with both the amounts and sizes of these η-phase particles increasing with decreasing cooling rate.
Oxidation of Rolled and Flash Anodized 3000 Aluminum in Air, Nitrogen, Oxygen, and Carbon Dioxide Atmospheres
Authors: Stevens Darcy , Kvithyld Anne , Engh Thorvald Abel
Published: August 2011

Thermal oxidation of a 3000 Al sheet rolled alloy was carried out in various atmospheres with a thermogravimetric analyzer (TGA). The effect of a flash anodized surface versus an untreated rolled surface is investigated. All samples were oxidized for 4 hours at 800°C. Samples oxidized in air, 100 % CO2 and 50% CO2–50% air, showed no difference in total oxidation. The flash anodized samples oxidized in 10% CO2–90% air had approximately half of the mass gain of the rolled samples. Oxidation of anodized samples in pure oxygen and nitrogen showed a drastic decrease in the amount of mass gained compared to the other atmospheres. Flash anodized samples gave consistent results, and the oxidation behavior tended to be linear or S-shaped for the 4 hours investigated. Rolled samples gave less consistent data and tended to be decelerating curves. Transmission electron microscope (TEM) analysis of the oxide layer before and after showed magnesium diffusion toward the surface of the sample, with a steep gradient over a distance of 400 µm. The flash anodized oxide layer was often difficult to find, having been removed during of the TEM sample preparation, but was found to double in size from 200 to 400 µm when located.
Low Temperature Wet-Chemical Synthesis BaTiO3 Nano-Particles by Tetra-N-Butyl Titanate [Ti-(O-C4H9)4]
Authors: Zeng Min , Ma Yong Jun , Chen Sheng Wei , Pei Chong Hua
Published: August 2011

Barium titanate nano-particles were prepared by heating the mixture of barium hydroxide aqueous solution and titania derived from the hydrolysis of Tetra-n-butyl Titanate [Ti-(O-C4H9)4]. The well-crystallized cubic phase BaTiO3 fine particles were obtained by heating at more than 328 K for 24 h. The morphology and size of the obtained nano-particles depended on the heating temperature and the reaction molar ratio Ba/Ti. In addition, the secondary particles with the larger size were obtained at a lower heating temperature. It is considered that the nucleation process of BaTiO3 depended on the heating temperature and the reaction concentration.
Electroluminescence Properties of ZnO Nano-Particles Embedded in Polyimide
Authors: Lin Jia Qi , Shi Jun Hui , Leng Jing , Xia Ming Hui , Chi Qing Guo
Published: August 2011

In this paper, ZnO Nano-particles is embedded in polyimide, and physical and chemical properties of polyimide/ZnO composite materials have been studied. It is found that different ZnO content will cause UV absorption edge blue shift, and EL tests show that electricity aging and pre-breakdown have changed. For PI/ZnO(1%) and PI/ZnO(2%) composite materials, Electricity aging is at 1.4Mv/cm and 1.5Mv/cm, Pre-breakdown field is at 1.9Mv/cm and 1.8Mv/cm, respectively. In addition, there are emission peaks at 442.8nm, 514.2nm, 609.4nm in the EL spectrum of the PI/ZnO (1%) films and 538nm, 633.2nm of PI/ZnO(2%) films, which indicates that some defects in this area.
Synthesis of Nanocrystalline LaFeO3 by Precipitation and its Visible-Light Photocatalytic Activity
Authors: Tang Pei Song , Fu Meng Bi , Chen Hai Feng , Cao Feng
Published: August 2011

The LaFeO3 nanoparticle was synthesized using Fe(NO3)3 and La(NO3)3 as starting materials by homogeneous precipitation method. The as-prepared LaFeO3 product was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible diffuse reflectance spectroscopy (DRS). XRD and SEM demonstrate the successful synthesis of single phase perovskite LaFeO3 and with 60-80 nm particle size. It was found that the as-prepared LaFeO3 shows strong visible-light absorption with absorption onset of 532 nm, indicating a narrow optical band gap of 2.33 eV. Furthermore, the as-prepared LaFeO3 shows high visible-light photocatalytic activity for decomposition of methylene blue in comparison with the commercial Degussa P25.
ZnO Nanorods Based Ammonia Gas Sensors with Interdigitized Electrodes
Authors: Chen Tai You , Wu Jian Sheng , Hsu Chi Shiang , Chou Po Cheng , Chen Huey Ing , Lin Kun Wei , Liu Wen Chau
Published: August 2011

The ZnO nanorods-based ammonia (NH3) gas sensors with different electrode spacing are fabricated and studied. Experimentally, the hexagonal ZnO nanorods were prepared by a hydrothermal method. The diameter and length of ZnO nanorods were about 179±2, 1806±5 nm, respectively. By shrinking the electrode spacing, the sensor response of studied device is improved and the sensor response is enhanced more than ten times in magnitude. The improved NH3 sensing ability caused by shrink electrode spacing is attributed to the presence of more grain boundaries and depletion layers. Therefore, the studied device with the shrink of electrode spacing provides a promise for high-performance ammonia sensing applications.
Interactions Analysis in BSA-Loaded Chitosan Nanoparticles at Different pH Values
Authors: Liu Yong , Sun Yan , Li Yan Li , Xu Shao Chun , Xu Yao Xing
Published: August 2011

In this paper, the properties of chitosan nanoparticles and bovine serum albumin-loaded chitosan nanoparticles prepared with sodium tripolyphosphate at different pH values were discussed. Interactions in chitosan nanoparticles and bovine serum albumin-loaded chitosan nanoparticles were analyzed by Fourier transform infrared spectroscopy and differential scanning calorimetry. The results indicated that there were more complicated interactions in chitosan nanoparticles prepared at different pH values. When the pH values were lower or higher than isoelectric point value of target protein (bovine serum albumin), the big different interactions occurred in chitosan nanoparticles. These differences also would result in different releasing properties.
Preparation and Exothermic Characterization of Hydroxyl-Terminated Polybutadiene(HTPB)-Coated Aluminum Nanopowders
Authors: Huang Kai Jin , Tan Chao Dong , Xie Chang Sheng
Published: August 2011

The HTPB-coated aluminum nanopowders were prepared by using horizontally-mounted kneading machine. The HTPB-coated aluminum nanopowders were characterized by TEM, XRD and FTIR. The exothermic characterization of the HTPB-coated aluminum nanopowders was analysized by simultaneous TG-DSC. The results show that the HTPB-coated aluminum nanopowders have a core-shell structure and the release heat enthalpy in pure oxygen is 4.954KJ/g at 542.7°C. The stability of HTPB-coated aluminum nanopowders excelled Al2O3-passivated aluminum nanopowders due to the hydrophobic nature of HTPB and the hydrophilic nature of Al2O3.
Study on Cytotoxicity of Nanoscale Zero Valent Iron Particles
Authors: Wang Xue , Dong Mei Ying , Liu Ling , Liu Ying , Jin Zhao Hui , Li Tie Long
Published: August 2011

Although small nZNI nanoparticles are useful in various applications, the biosafety of this material needs to be evaluated. In this study, Escherichia coli cells were exposed to 0, 112, 560, 1120 mg/L of nano-Fe0particles, respectively. Experiments were carried out to examine the activities of lactate dehydrogenase (LDH), cellular superoxide dismutase (SOD), and malondialdehyde (MDA) after exposure to nano-Fe0 for 24h. The activities of LDH and the levels of MDA were significantly increased (P<0.05), respectively. However, the activities of SOD were significantly decreased (P<0.05). A dose dependent increase in lipid peroxidation product (MDA) contents was observed in treatment groups(r=0.945, P<0.05).The result demonstrated that the damage to cell membranes and oxidative stress were mechanisms of nano-Fe0 ecotoxicity.
Piezoelectric Potential Distribution in a Bent ZnO Nanorod Cantilever
Authors: Shao Zheng Zheng , Zhang Xue Ao , Wang Fei , Wang Guang , Jia Hong Hui , Chang Sheng Li , Zhang Hai Liang , Fang Liang
Published: August 2011

The piezoelectric potential generated in a bent ZnO nanorod cantilever is analyzed by means of the first piezoelectric effect approximation. The results show that the piezoelectric potential in the nanorod is proportional to lateral force but is independent along the longitudinal direction. And the electric potential in the tensile area and that of compressive area are antisymmetric in cross section of the nanorod, which makes the nanorod become a "parallel plated capacitor" for piezoelectric nanodevices, such as nanogenerator. The investigation of the carriers influence on the piezoelectric potential in a bent ZnO nanorod reveals that the positive piezoelectric potential in stretched side of the bent nanorod is significantly screened by the carriers and the negative potential in compressed side is well preserved when considering a moderate carrier concentration of
Nanotechnology Applications in the Field of Ship Protection
Authors: Jiang Yan Lan , Liang Xiao Rui , Wu Shi Yong
Published: August 2011

Based on the characteristics of nano-material and ship corrosion, the excellent properties of nano -painting ,such as toughening, wear resistance, anticorrosion, antipollusion etc. are introduced in this paper . Furthermore, in order to help relevant people to know well current development level and trend，on the basis of some informations, the current status of nano-painting research and application in marine protection are also discussed.
Hydrothermal Synthesis and Characterizations of Cobalt-Doped ZnO Nanostructures
Authors: Zhu Lu Ping , Bing Nai Ci , Yang Dan Dan , Jin Hai Ying
Published: August 2011

Pure and Cobalt-doped ZnO nanostructures have been synthesized by a hydrothermal process. The samples were characterized by X-ray diffraction (XRD), UV-Vis diffusion reflectance spectra (DRS) and X-ray energy dispersion spectroscopy (EDS). The structure and morphology analyses show that Co doping can influence the nanostructures morphology, but cannot change the crystal structures of ZnO samples. The DRS spectra showed that Co dopant enhanced the ability of visible light absorption of the ZnO samples
Influence of Hydrogen Concentration on TiO2 Nanoparticles Prepared by Gaseous Detonation
Authors: Yan Hong Hao , Huang Xian Chao , Xi Shu Xiong
Published: August 2011

This article is mainly introduced the detonation method to prepare TiO2 nanoparticles which use hydrogen-oxygen gas mixture as the explosion source and the titanium tetrachloride as the precursor. It studied TiO2 nanoparticles influenced by different hydrogen concertration. And analyzed the character of prepared TiO2 nanoparticles by XRD and TEM. The results show that the powders are mixed crystal of Rutile and Anatase. It is also found that the relative content of rutile grows larger and the size of grain becomes smaller (about 30~100nm) as the hydrogen content increases, and the TiO2 nanoparticles are mostly spherical. But the dispersion is becomes slightly worse, and the agglomeration appear.
Influence of Concentration Modes on Morphology of Nano-Silver
Authors: Li Wei Wei , Li Lu Hai , Hu Xu Wei , Fang Hua , Leng Xian , Li Wen Bo , Li Shu Kun
Published: August 2011

In order to compare different concentration modes' influence on the nano-silver particle size and morphology,we use three methods to refine nano-silver solution prepared in the lab as:1 centrifugal the solution directly,2 deposit the solution with acetone,3 centrifugal the solution with acetone added.Then test the solution processed with particle size distribution,UV-vis and SEM.The result shows that:the particle sizes of the nano-silver solutions enriched with the three methods are 162.5nm,163.5nm,164nm;the peak of the UV-vis absorption curve are 425nm, 426.5nm,427nm,we can see that different methods of enrichment have less influence on the nano-silver particles' size and morphology. Also the same conclusion can be drawn from SEM test.
A Novel Chemical Reduction Route towards the Synthesis of Nickel Nanoparticles at Room Temperature
Authors: Wu Zhi Gang
Published: August 2011

Pure metallic nickel nanoparticles, spherical shape have been successfully synthesized by the chemical reduction of nickel chloride with hydrazine at room temperature without any protective agent and inert gas protection. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were employed to characterize the nickel nanoparticles and of course, the magnetic properties were also measured. This synthetic method is proven to be simple and very facile. And it’s very interesting that the obtained nickel nanoparticle can be isolated in solid states and stabilized for several months in atmosphere.
Study on on-Line Detecting of Total Phosphorus by Nano-TiO2-UV Photoelectron-Catalysis Oxidation Method
Authors: Sun Mo Jie , Wang Peng , Shan Yu Han , Zhang Chun Biao
Published: August 2011

In this paper, we made the nano-TiO2/glass composite electrode through the sol-gel method by using tetrabutyl titanate and anhydrous alcohol as the raw materials and the ITO conductive glass as the carrier. With the help of the photoelectric catalytic effect of TiO2 and the strong oxidation of Na2S2O8 as well as the computer application technology, we decomposed rapidly of the organophosphorous compounds and detected the total phosphorous (TP) on-line accurately. And then we characterized the TiO2 particles by SEM and analyzed the factors which influenced the decomposition and detection of TP by this method. The results show that the optimum experimental conditions of this method should be as follow: the concentration of Na2S2O8 is 0.03mol/L, UV illuminating time is 10 min, electrode voltage is 8V and the pH value should be in the alkaline zone. At last, it is validated the method is reliable and accurate for the decomposition of the organophosphorous by the recovery experiments and the comparative experiments between this method and national standard method.
Synthesis and Electrochemical Performance of Poly(N-Acetylaniline)/Carbon Nanotubes Composite for Supercapacitors
Authors: Li Jing , Xie Hua Qing , Li Yang , Wang Ji Fen
Published: August 2011

Poly(N-acetylaniline)/multi-walled carbon nanotubes composite (PAANI/MWCNTs) are synthesized using electrochemical method. The morphology of the composite is examined by scanning electron microscopy. Electrochemical properties are characterized by cyclic voltammetry and galvanostatic charge/discharge. A remarkable specific capacitance of 690 F g-1 is obtained at a current density of 2.5 A g-1, compared to 225 F g-1 for pure PAANI and 90 F g-1 for MWCNTs. The composite presents excellent cycle stability, losing 15% of the maximum capacity after 1000 cycles.
Study on CH4 Conversion over Ce-Zr Solid Solution Supported Nano Ni-Pt Bimetallic Catalysts: Preparation and Characterization of Catalysts
Authors: Yang Min , Dang Qiong , Xie Zhi Min , Guo Hai Jun
Published: August 2011

The Ni-Pt/Ce0.7Zr0.3O2 catalysts were prepared by different impregnation methods. Study the properties of samples by XRD、TEM and H2-TPR etc. The results indicated that, bimetallic catalysts have better physico-chemical performance than monometallic catalysts, the loading of Pt and impregnation sequence has some effect on Ni-Pt bimetallic catalysts.
Study on the Synthesis and Properties of Nano-ZnO
Authors: Liu Zong Rui , Hou Jie , Duan Li Mei , Xu Ling
Published: August 2011

Nano-ZnO was synthesized by sol-gel method using acetic acid zinc and ammonia as raw material and characterized by XRD, SEM, TEM and N2 adsorption-desorption measurements. In addition, the photoluminescence performance of nano-ZnO was analyzed through PL spectra. The particle size and dispersion degree of nano-ZnO could be controlled by adjusting the addition of surfactant polyethylene glycol-4000. The characterization results revealed that the crystallinity and dispersion degree of nano-ZnO were high and the surface area of nano-ZnO was large, when the amount of polyethylene glycol-4000 was 293.44 mg.
Prepared and Magnetic Properties of B4C/C Coated Co Nanocapsules
Authors: Yu Da Wei , Zhang Jin Bing , Shi Gui Mei
Published: August 2011

B4C/C coated Co nanocapsules were prepared by arc-discharging a Co-B amorphous alloy. The structure, morphology and surface composition as well as magnetic properties were investigated by X-Ray diffraction, High Resolution Transmission Electron Microscopy and XPS photoelectron spectrum as well as Vibrating Sample Magnetometer, respectively. The results show the as-prepared nanoparticles form in a core¬¬¬-shell structure with the size of nanoparticles in range of 20-100nm, the thickness of the shell is about 3-10nm. The core is Co grains, while the shell is B4C/C compound. That B4C coated Co nanoparticles form in a core¬¬¬-shell structure ascribed to Co as catalysts accelerating reaction between B with C ionize in the arc-discharge course. This structure can prevent Co nanoparticles from oxidation and agglomeration. A saturation magnetization of Ms=75.6 Am2/kg and a coercive force of Hc=20.1 kA/m are achieved for as-prepared nanocapsules by VSM. For as–prepared nanocapsules, the saturation magnetization is reduced and coercive force of is enhanced while Comparing with Co block. The increase coercive force for as-prepared nanoparticles can be mainly ascribed to size of particles diminished and the domain-wall depinned in the multi-domain particles.
Investigation on Heat Transfer Performances of Nanofluids in Solar Collector
Authors: Li Yang , Xie Hua Qing , Yu Wei , Li Jing
Published: August 2011

Nanofluids containing Al2O3, ZnO, and MgO nanoparticles were prepared with distilled water as base fluid by violent stirring and ultrasonic dispersing. The forced convective heat transfer performances of the as-prepared nanofluids in tubular solar collector were investigated. The experimental results showed that the heat transfer efficiencies of Al2O3, ZnO, and MgO nanofluids were all increased in comparison to distilled water. For 1.0% vol. Al2O3, ZnO, and MgO nanofluids, the difference in temperature between nanofluids and distilled water all could exceed 3 °C in a day’s cycling. In daytime, from 6:00 a.m. to 18:00 p.m., the maximum differences in temperature of nanofluids and distilled water appeared at about 10:00 a.m., while the maximum temperatures were achieved at about 15:00 p.m. for both nanofluids and distilled water. In night, the temperatures of nanofluids still keep more than 1 °C higher than distilled water, which indicated that nanofluids could retain more heat energy. The viscosities and heat transfer efficiencies augmented with concentration increasing for ZnO nanofluids. Even at 0.2% vol. concentration, the difference in temperature between ZnO nanofluids and distilled could reach 2.55 °C. Based on low viscosity and excellent heat transfer performance, 0.2% vol. concentration ZnO nanofluid was an attractive option to be applied in solar energy utilization.
Research the Al Material Reinforced by CNT(Carbon Nanotubes)
Authors: Cai Xiao Lan , Wang Xiao Fei
Published: August 2011

This paper using high energy ball milling(HEM), researched the technology of preparation of Al compound material reinforced by CNT. Researched the different milling time, rotary speed, amount of CNT and sinter technology on properties of hardness and density. Preparation the Al-CNT at milling time about 30 to 100 min, rotational speed is about 300-600/rpm.the wt% of CNT is 0-5%, Analyzed the XRD patterns、SEM and STM micrograph, the results showed the Al material could be reinforced by CNT using HEM. the hardness of Al-CNT is 75 HB and the density is 2.65 g/cm3 when milling 90 min and CNT 3%.
Preparation of PVC/Kaolin Nanocomposites through Solid State Shear Compounding Based on Pan-Milling
Authors: Li Kan She , Chen Ying Hong , Niu Hong Mei , Chen Jian Jun
Published: August 2011

Solid state shear compounding technology (S3C) based on pan-milling is an effective method to prepare polymer/layered mineral composites with nano intercalating structure. The PVC/Kaolin compounding powders were successfully prepared by pan-milling at ambient temperature, and then the PVC/Kaolin nanocomposites were processed by moulding The structure and properties of PVC/Kaolin compounding powder and nanocomposites were investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and mechanical tests. The results showed that the mechanical properties of PVC/Kaolin nanocomposites prepared through S3C based on pan-milling 30 cycles at ambient temperature including elongation, tensile strength and notched impact strength were remarkably improved compared with conventional filled composites. The elongation of PVC / Kaolin nanocomposites with 4 %wt. Kaolin was 274.6%, which is 187.3 % higher than that for a conventional filled composite. The tensile strength was 54.0 MPa, which is 6.3 MPa higher than that for a conventional filled composite. The tensile strength of the nanocomposites with 8 %wt. Kaolin was 57.5 MPa, which is 9.1 MPa higher than that for a conventional filled composite. At the same time, the notched impact strength was 4.9 kJ/m2, which is 1.0 kJ/m2 higher than a conventional filled composite. Strengthening and toughening for PVC were synchronously realized. XRD, SEM and TEM verified that S3C based on pan-milling realized synchronously pulverizing, dispersion and compounding of PVC with kaolin Through 25-30 cycles pan-milling, PVC and Kaolin powders imbedded each other and made into uniform PVC/Kaolin compounding powders and nanocomposites. The strip flake of Kaolin particles with thickness less than 50 nanometer and the aspect ratio of 10 times dispersed homogeneously in the PVC matrix.
Freeze-Drying and Characterization of Vitamin a Palmitate-Loaded Nanostructured Lipid Carriers (NLC)
Authors: Xia Qiang , Kong Rong
Published: August 2011

Vitamin A Palmitate-loaded Nanostructured Lipid Carriers (VAP-NLC) were prepared by High Pressure Homogenization (HPH) technique. Trehalose, glucose, mannitol, α-lactin, D-sorbitol, D-maltose monohydrate and sucrose were chosen as the cryoprotectants. Also, the centrifugal stability of VAP-NLC dispersions after diluting different times and the effects of cryoprotectants on the diameter during the freeze-drying process were investigated extensively. Glucose and α-lactin proved to be the most effective in preventing particles aggregation during the VAP-NLC freeze-drying process. The most suitable concentrations were proved to be 5 wt% and 5 wt%, respectively when the dilution times of VAP-NLC dispersions reached 7 or more before freeze-drying. In conclusion, the NLC formulation demonstrated a promising perspective for oral delivery of poorly water-soluble actives in food industry.
WS2 Nanotubes Prepared by Aluminum Oxide Template
Authors: Yu Dong Bo , Feng Yi , Zhu Yan Fang , Zhang Xue Bin , Li Bin , Liu Hui Qiang
Published: August 2011

Tungsten disulfide nanotubes were fabricated by means of decomposition of ammonium tetrathiotungstate ((NH4)2WS4) on anodized aluminum oxide (AAO) template. The morphology and structures of WS2 nanotubes were characterized by transmission electron microscopy (TEM), electron diffraction. The nanopores in template, the incorporation method and soakage time have function on the structure of WS2 nanotubes.
Magnetic and Microwave Absorption Properties of Ni1-XCoxFe2O4 Nanometer Powders in GHz Frequencies
Authors: Xu Chao
Published: August 2011

The nanosized Ni1-xCoxFe2O4 (x=0, 0.1, 0.3, 0.5) ferrite particles were prepared by sol-gel technique. The characterization studies such as XRD, VSM and Vector Network Analyzer have been carried out to explore the crystal structure, magnetic properties and electromagnetic parameters of the samples. The relation of the saturation magnetization, coercivity, complex permeability and permittivity to the cobalt content and the frequency of microwave were analysed qualitatively. The results indicate that all the samples annealed for 2 hours at 800°C exhibit spinel ferrite structure. It is shown that the magnetic loss and dielectric loss are obvious improved for the x=0.1 sample in 0.1-1.5GHz frequency band, but the loss properties decrease when the content of Co continue increasing.
Spectroscopic Investigated to the Interaction of Human Serum Albumin with Fluorescence Carbon Nanoparticles
Authors: Jin Fen
Published: August 2011

The interaction of SiO2 including carbon nanoparticles (CNPs) with human serum albumin (HSA) in vitro under simulated physiological conditions has been studied by fluorescence methods and dynamic light scattering (DLS). Experimental results indicated that SiO2 including CNPs can be stabilized in the physiological environment and emit fluorescence, which quench HSA ﬂuorescence by a static quenching mechanism. Our findings indicate that understanding the interaction between proteins and carbon nanoparticles is crucial for toxicological studies.
Hydrogen Generation by Photoelectrochemical Splitting of Water by Using CdS/TiO2 Nanotube Photoanode
Authors: Lin Kuan Wen , Lin Fa , Hsu Kao Kan , You Bo Shing , Chen Huey Ing
Published: August 2011

In this study, hydrogen is generated from water via photoelectrochemical (PEC) process by using CdS/TiO2 photoanode, which is obtained in sequence chemical bath deposition (s-CBD) process. Experimentally, the CdS was deposited on TiO2 NTAs in s-CBD process. First, the TiO2 NTAs is immersed in Cd(NO3)2 and Na2S solution subsequently several cycles followed by annealing to get CdS/TiO2 photoanode. In this work, the factors were studied including immersion cycle, annealing temperature and UV illumination. The surface morphology, crystalline structure and CdS amount were characterized by SEM and XRD. The photoactivities of CdS/TiO2 photoanodes and hydrogen generation rate were investigated by PEC splitting of water. The results showed that the photoanode annealing in air at 300 °C had the highest photoactivity and the crystalline structure of CdS was composed of zinc blende and a small amount of wurtzite. The saturated current density was 6.163 mA/cm2 and the maximum photoelectrochemical conversion was 4.45 % under Xenon lamp (I0 = 100 mW/cm2) illumination. Besides, the photoactivity of CdS(UV)/TiO2 prepared under UV (λmax=253.7 nm) illumination was reduced. This was probably due to the aggregation of CdS. To sum up, the CdS/TiO2 photoanodes for photoelectrochemical splitting water could be a high prospective process of the energy source.
Fabrication and Luminance Properties of Field Emission Backlight Unit Based on SnO2 Nanowires
Authors: Wang Ling Jie , Wu Cao Xing , Ye Yun , Guo Tai Liang
Published: August 2011

In this paper, SnO2 nanowires were synthesized by thermal evaporation. The structure and morphology of SnO2 nanowires were investigated in detail, and then the nanowires were transferred to cathode electrode by printing. Field-emission measurement revealed that the average luminance of SnO2 nanowires FE-BLU was 2340 cd/m2 with the uniformity of 88.1% when the applied field was 3 V/μm. The results demonstrated that the FE-BLU based on SnO2 nanowires holds potential for application in the backlight of liquid crystal display (LCD).
Effect of Alumina Content on the Properties of Ceramic Foams Crystallized with Nano-Sized Mullite Crystals
Authors: Sooksaen Pat
Published: August 2011

Ceramic foam is a class of materials with high porosity and three-dimensional network of struts. In this study, ceramic foams were fabricated by polymeric sponge method using commercial PVA foam as a replica template. The study focused on the effect of alumina content on the physical and mechanical properties of such ceramic foams sintered at 1500°C for different sintering times. It was found that ceramic composition with higher amount of alumina required higher sintering temperature than that used in the present study. Physical properties and mechanical strengths depended upon ceramic composition as well as sintering time. Microstructural analysis revealed the evolution of primary cuboidal mullite and needle-like nano-sized mullite phase in the sintered sample. This fine needle-like phase added to mechanical strengths of ceramics.
Preparation and Magnetic Properties of the Core-Nanoshell Composite Materials Doped with Sm
Authors: Che Ru Xin , Yu Bing , Wang Chun Xia
Published: August 2011

The core-nanoshell composite materials doped with Sm were prepared by a solid-state reaction method. The core is magnetic fly-ash hollow cenosphere, and the shell is the nanosized ferrite doped with Sm. The thermal decomposition process of the sample was investigated by thermogravimetric analysis-differential scanning calorimetry ( TG- DSC ). The morphology and composition of the composite materials were investigated by the X-ray diffraction analysis ( XRD ), scanning electron microscope ( SEM ) and energy disperse spectroscopy ( EDS ). The results of vibrating sample magnetometer analysis ( VSM ) indicated that the exchange-coupling interaction happens between ferrite of magnetic fly-ash hollow cenosphere and nanosized ferrite coating, which caused outstanding magnetic properties. The results show that doped with Sm can enhance the coercivity too, so the magnetic properties could be promoted further by the adjustment of compositions and the use of special techniques. The magnetic properties of the core-nanoshell composite material are better than that of single-phase.
Effect of Different Acid Treatment on Surface Characteristics of Titanium Alloy
Authors: Zhang De Gui , Cheng Hai Mei , Wang Ying Jun , Ning Cheng Yun
Published: August 2011

This study was aimed to investigate the effects of acid treatment on the surfacee characteristics ofgrit-blasted titanium alloy (Ti6Al4V). These treatments included (a) Al2O3 blasting, (b) Al2O3 blasting + HF acid etching, (c) Al2O3 blasting + HCl/H2SO4 acid etching, and (d) Al2O3 blasting + HF acid etching + HCl/H2SO4 acid etching. The surface topography and chemical composition of the samples were identified by field-emission scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. Roughness of the as-treated samples was obtained from atomic force microscopy (AFM) and profilometry. Wettability of the samples was measured using sessile drop method. The results showed that porous structure on the surface of titanium alloy was prepared by dual acid etching treatment and the surfaces treated with acid had higher roughness and better wettability than the surface treated only by grit-blasting.
The Electrostatic Tangential Resistance of the MEMS Moving Plate with Bumps Considering the Edge Effects
Authors: Shen Xue Jin , Wang Zhen Liang , Zhou Ling
Published: August 2011

Friction force is present in most microelectromechanical systems (MEMS), since they have a large ratio of surface area to their volume. To improve the performance and reliability of MEMS devices, it is necessary to fully understand the effect of friction which exists in the majority of MEMS. For the MEMS’s moving plate with bumps, the model of electrostatic tangential force is established based on the rule of energy conservation, and it is further revised considering the edge effects by the conformal mapping method. Three types of the electrostatic tangential resistance of the MEMS’s moving plate with bumps, which are the unrevised theoretical value and revised theoretical value considering the edge effects and simulation value, were compared. The effects of the applied voltage, the rate of all micro bumps projective area to the moving plate area, and the relative surface roughness are investigated, and the electrostatic tangential resistance between two charged moving plates with respect to each other is analyzed. It is found that the three types of the electrostatic tangential resistance will be increased with the increase of the applied voltage. The revised analytic results considering the edge effects are larger than the ones not revised, and the former are close to results of ANSYS simulation.
Microstructure and Mechanical Properties of FeCrNiCoCu(B) High-Entropy Alloy Coatings
Authors: Liang Xiu Bing , Guo Wei , Chen Yong Xiong , Wang Lin Lei
Published: August 2011

Two kinds of high-entropy alloy coatings of FeCrNiCoCu and FeCrNiCoCuB were deposited on AZ91 magnesium alloy substrate using high velocity arc spraying technology. Microstructure and general mechanical properties of the coatings were investigated with Scanning Electronic Microscope (SEM), X-Ray Diffraction instrument (XRD), microhardness tester and strength bond tester. The results show that the two kinds of coatings exhibit compact layered microstructure and the phase lattice type are both FCC, the microhardness of the FeCrNiCoCu and FeCrNiCoCuB coatings are 414HV0.1 and 342HV0.1 respectively, the bond strength are 36.9 MPa and 33.6 MPa respectively.
Photoluminescence Properties of NaLa(WO4)2:Tb3+ Novel Green Phosphors Prepared by the Combustion Method
Authors: Qian Xian Hua , Pu Xi Peng , Zhang Da Feng , Cui Shi Cai , Gao Yan Yan
Published: August 2011

A series of NaLa(WO4)2:Tb3+ green phosphors have been prepared by a facile combustion method. X-ray powder diffraction (XRD) and photoluminescence were used to characterize the structure and luminescence properties of as-synthesized phosphors, respectively. The XRD results confirm that the as-synthesized phosphors exhibit sheelite-type structure without any impurity phase. The excitation band of the phosphors covers a wide region of 200-300 nm. The as-obtained phosphors emit strong green light centered at 546 nm under ultraviolet light excitation (261 nm). The results show that the optimum temperature is 800°C and the optimum concentration of Tb3+-dopant is 50 at%.
Research on Hydrogen Bonding Interaction of Trigonal Schiff Base Compound with Barbituric Acid in Organized Molecular Films
Authors: Jiao Ti Feng , Zhou Jing Xin
Published: August 2011

In order to investigate the supramolecular assembly and intermolecular hydrogen bonding of special amphiphile, a trigonal Schiff base compound was designed and synthesized, and it supramolecular assembly and interaction properties were investigated by spectral measurements. It was found that the Schiff base compound can be spread on water surface to form stable monolayer. When it was spread on the subphase containing barbituric acid, it can show hydrogen bonding interaction with barbituric acid. Due to the directionality and strong matching of hydrogen bond, two barbituric acid molecules can be encapsulated into intramolecular space of the trigonal Schiff base compound through intermolecular H-bonding to form a 1:2 complex. A rational complex mode was proposed.
Synthesis and Characterization of Functional Cholesteryl Substituted Luminol Derivative
Authors: Jiao Ti Feng , Xing Yuan Yuan , Zhou Jing Xin
Published: August 2011

Functional luminol derivative with cholesteryl substituted group has been designed and synthesized from the reaction of the corresponding precursor cholesteryl chloroformate with luminol. It has been found that depending on cholesteryl substituted group, the formed luminol derivative showed different properties, indicating distinct regulation of molecular skeleton. UV and IR data confirmed commonly the formation of imide group as well as cholesteryl segment in molecular structure. Thermal analysis showed that the thermal stability of luminol derivative with cholesteryl segment was different from luminol. The difference of thermal stability is mainly attributed to the formation of imide group and cholesteryl substituent group in molecular structure. The present results have demonstrated that the special properties of luminol derivative can be turned by modifying molecular structure of objective compound with proper substituted groups, which show potential application in functional material fields such as liquid crystal and ECL sensor.
A Timesaving Solution Route for Hollow Polymer Microspheres by Alkali Neutralization Method
Authors: Nie Dong Mei , Duan Tao , Tang Yong Jian
Published: August 2011

A novel and timesaving preparing process for hollow polymer microspheres(HPMs) was proposed based on the improved alkali neutralization method. In the process, uniform HPMs were prepared by synthesizing poly(styrene-methacrylic acid){P(St-MAA)} particles with carboxylic functional groups by emulsion polymerization and subsequently hydrophilic and hydrophobic phases separating by alkali neutralizing. The morphology, diameter and monodispersion of P(St-MAA) particles were controlled by varying the content of methacrylic acid(MAA). Scanning electron microscopy(SEM) and transmission electron microscopy(TEM) were used to characterize the products and to demonstrate that the polymer microspheres were hollow. The results indicated that the optimum MAA content was about 10%.
Synthesis and Properties of Fe3O4 Ferrofluids with Narrow Particle Size Distribution
Authors: Zhang Jian Hui , Sun Hai Bo
Published: August 2011

Fe3O4 ferrofluids with uniform magnetic particles were prepared via improved chemical coprecipation technique. A narrow distribution of 8.6-10.8 nm particle sizes was obtained from the magnetization curve using the free-form-model based on Bayesian inference theory. The mean particle diameter about 9.8 nm is consistent with the XRD and SEM results. The hydrodynamic properties of ferrofluids were investigated with different applied magnetic field and shear rate. The experimental results show that diluted ferrofluid and concentrated ferrofluid are Newtonian-fluid and Bingham-plastic fluid, respectively.
Design and Fabrication of Low-Power Planar Type Gas Sensor
Authors: Zhang Zi Li , Yin Chen Bo , Tao Chun Min , Zhu Bin
Published: August 2011

In this paper we describe the fabrication steps and the implementation of a planar type gas sensing applications with suspended structure, which presents very low power consumption. Simulations with the finite element model tool show homogeneous temperature distribution across the sensitive film. The device attached with a spin-coated thin layer of SnO2 showed a reasonable sensing performance to hydrogen.
The Effect of Multi-Step Anodic Oxidation
Authors: Zhen Ying , Wang Hai , Jia Xiang Rui , Jiang Hong Wei , Liu Jiang Tao
Published: August 2011

The order of nanopores in anodic aluminium oxide (AAO) membrane formed by multi-step anodization in oxalic acid solution under a constant voltage of 40 V was studied. The average pore diameter increases slightly from 70 nm after two-step anodizing to 75 nm by six-step anodizing. The wall between neighboring pores becomes thinner from 40 nm after two-step anodization to 25 nm by six-step anodization. The interpore distance keeps a constant 105 nm. The orderly domain size is limited to micron size and increases for the two-step and three-step anodization, but the average size of the ordered domains remains constant after three-step anodization under the same working voltage. Moreover, surprisingly, “microflower-like” structures are observed over the surface of highly ordered AAO membrane after six-step anodic oxidation. We assume that they generate with the formation of the nanopores in the anodizing process.
The Tribological Properties of (n-palmitic acid)-N-quinazolin-4-one Methylester as Additive in Liquid Paraffin
Authors: Ouyang Ping
Published: August 2011

A heterocyclic derivative of (n-palmitic acid)-N-quinazolin-4-one methylester was synthesized and its tribological behavior as an ashless additve without phosphorus and sulphur in liquid paraffin was evaluated using a four-ball tester. On the basis of the experimental results, the novel additive has been found to be quite effective as a potential additive in liquid paraffin. The nature of the film on the rubbed surface was investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).
Mn and MnZn Ferrite Powders Prepared by Detonation of Emulsion Explosives
Authors: Li Xiao Jie , Wang Xiao Hong , Yan Hong Hao , Xue Li , Luo Ning
Published: August 2011

In the present work, nano Mn and MnZn ferrite powders were prepared by detonation of emulsion explosives, XRD(X-ray diffraction),TEM(transmission electron microscope) and VSM(vibrating sample magnetometer) experiments were carried out respectively to characterize and research the prepared powders. Results indicated that the average particle size of the raw Mn and MnZn ferrite powders was around 30nm, and Zn2+ seriously destroyed and reduced the dispersity and homogeneity of the powders although they were successfully doped in nano-Mn ferrite crystals. The average particle size, the specific residual magnetization(σr) and the coercivity(Hc) of the powders were all decreased with the increasing of the hexogen(for short, RDX) content.
Mechanical Behavior of CNTs/SiCp/AZ91D Magnesium Matrix Composites
Authors: Li Wei Xue , Nie Yun Feng , Wang Dun Dong
Published: August 2011

AZ91D alloy composites reinforced by CNTs/SiCp were fabricated using stir casting process. The mechanical properties of the composites were tested, observed and analyzed the microstructure, the fractographs were observed and analyzed via scanning electron microscope. The results showed that CNTs/SiCp could not only refine the grains of the composites, but also bear the load of resistance to deformation. Compared with the matrix alloy, the tensile strength, the elastic modulus, the micro-hardness and the elongation rate of the composites had been enhanced significantly. But the mechanical properties would be fell down with the more addition of CNTs/SiCp.