bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Nano-Y2O3 on Crystallization Behavior and Sintering Performance of Fused Quartz Ceramic Materials
Authors: Chen Yue Jun , Wang Zhi Fa , Yu Li Xue , Bu Jing Long , Wang Rong Lin , Wang Rui Sheng
Published: July 2011

Fused quartz granule (d50=0.019 mm) was used as raw material, nano-Y2O3 (size<0.08 μm) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. Properties of samples were researched by measurements of apparent porosity, bending strength and thermal expansion rate, and analyzed by XRD and SEM. The results showed that additive nano-Y2O3 had good inhibiting effect on crystallization of fused quartz sintered at various temperatures, sample added 2% nano-Y2O3 had least thermal expansion rate, diffraction peak intensity and apparent porosity, and it had higher bending strength and more compact microstructure, especially sample sintered at 1350 °C. It can be deduced that 2% nano-Y2O3 plays the excellent role as the crystallization inhibitor and sintering assistant to fused quartz materials sintered at various temperatures.
Finite Element Simulation and Experimental Study of the Effect of Cone Angle on Thickness Distribution in Hydroforming of Conical-Cylindrical Cups
Authors: Gorji Abdolhamid , Bakhshi-Jooybari Mohammad , Nourouzi Salman , Hosseinipour S. Jamal , Mohammad-Alinejad G.
Published: July 2011

Forming conical parts is one of the complex and difficult fields in sheet metal forming processes. Because of low contact area of the sheet with the punch in the initial stages of forming, too much tension is applied to the sheet causing burst occurrence. Furthermore, since the major part of the sheet surface between the blank holder and punch tip is free, wrinkles appear on the wall of the drawn parts. Therefore, these parts are normally formed in industry by spinning, explosive forming or multi-stage deep drawing processes. In this paper, the effect of punch conical angle in hydroforming of conical-cylindrical parts has been studied. It is shown that by increasing the angle the thickness reduction will be reduced.
The Research on High Pressure Sintering of Mixed Powder γ-Si3N4 and α-Si3N4
Authors: Yao Huai , Wang Yong Zhi , Xu Bo
Published: July 2011

The high pressure and high temperature sintering of α-Si3N4 and γ-Si3N4 with Y2O3-Al2O3-La2O3 as additives were studied under pressures of 5.4 GPa and temperatures of 1420-1770 K. The effects of sintering temperatures and pressures on properties of sintered ceramic samples were investigated with X-ray diffraction and scanning electron microscopy. The results show that γ-Si3N4 and α-Si3N4 is transformed to β-Si3N4 completely. The highest relative densities and Vickers hardness (HV) of sintered samples are 98.71 and 21.76GPa, respectively. The sintered samples were composed of elongated β-Si3N4 rod crystals with disordered orientation and had intergranular interlocks and uniform and compact microstructure. Pulled out crystal grains on the fractured cross sections were obviously observed by SEM.
Formation Mechanism of Porous Silicon Carbide Ceramic Synthesized by Coat-Mix Process
Authors: Zhao Hong Sheng , Liu Zhong Guo , Zhang Kai Hong , Li Zi Qiang , Liu Xiao Xue
Published: July 2011

Porous silicon carbide ceramics were prepared by coat mix process using silicon powders and phenolic resin as silicon and carbon resource. The formation mechanism of silicon carbide was proposed based on the liquid silicon infiltration mechanism, reaction dynamics and thermodynamics analysis. Results show that the formation of silicon carbide by the coat mix process includes the following phases. 1) Infiltration of liquid silicon into porous carbon gap. 2) Formation of silicon carbide particles through the contact and reaction between liquid silicon and silicon surface. 3) Fracture and falling off of silicon carbide layer from the carbon surface. 4) Formation of new silicon carbide layer and particles. 5) The repetition of phase 3) and phase 4) till the reaction is complete and the porous silicon carbide ceramics are formed.
As(III) Removal from Low-Arsenic Concentration Drinking Water by Coagulation with Quadrivalent Titanium Coagulants
Authors: Tang Yu Chao , Huang Xian Huai , Wu Chang Nian , Tang Li Hua , Li Wei Hua , Peng Yan , Li Xin
Published: July 2011

As(III) removal from low-arsenic concentration drinking water treated by coagulation with mixture titanium tetrachloride and titanium sulfate as coagulants were studied in this paper. Without any pre-oxidation process, the residual concentration of As(III) after treated by the coagulant (concentration of 25mg/L) was less than 4μg/L,which can be satisfied the most rigid guideline for arsenic maximum contaminant level (MCL) proposed by WHO or USEPA. Operated with rapid water dynamics will get the better efficiency for As(III) removal. In the pH range of 3-6 the variation of As(III) removal efficiency was minimal, but the As(III) removal declined gradually with the increase of pH while in the alkaline range. Ferrous salts can significantly increase the efficiency of As(III) removal by coagulation treatment with mixed titanium salts as coagulant.
Structure and Microwave Dielectric Properties of (Ca0.9375Sr0.0625)0.25 (Li0.5Sm0.5)0.75TiO3 Ceramics with B2O3-CuO Sintering Aids
Authors: Li Yue Ming , Shen Zong Yang , Wang Zhu Mei , Zhang Hua , Hong Yan , Liao Run Hua
Published: July 2011

The B2O3-CuO oxide mixture (abbreviated as BC) was selected to lower the sintering temperature of (Ca0.9375Sr0.0625)0.25(Li0.5Sm0.5)0.75TiO3 (abbreviated as CSLST) microwave dielectric ceramics by solid sate reaction technique. The effects of BC doping amounts on the crystal structure, microstructure and microwave dielectric properties of the ceramics were investigated. For the ceramic sample with the composition of CSLST + 5 wt% BC, its sintering temperature was reduced to 1000 °C as compared to 1200 °C for pure CSLST. In addition to the obtained good microwave dielectric properties as follows: εr = 80.4, Q×f = 1380 GHz, τf = -32.89 ×10-6/°C, this ceramic was a desirable high-permittivity microwave dielectric candidate for low-temperature cofired ceramic (LTCC) applications.
Microstructure Evolution of ZK60M Twin-Roll-Casted Magnesium Alloy during Hot Compression and Annealing
Authors: Ma Ru , Wang Shou Ren , Wang Yong , Yang Li Ying
Published: July 2011

The effects of hot compression deformation (300°C/0.1s-1) and annealing on the microstructural evolution of ZK60+0.8Zn (ZK60M) alloys were investigated in the present works. Lots of sub-structures were studded in the shear bands under the deformed conditions, and after annealing, the sub-structures in the shear bands occurred static recrystallization following by the growth of recrystallized grains. With the increase of annealing temperature, amounts of twins decrease while static recrystallization (SRX) grains increase while dislocations rearrange forming sub-grains ultimately induced static recrystallization. And that, the micro structural evolution and grain boundary distribution of the specimen as-deformed and as-annealed at different temperatures were analyzed by electron back scatter diffraction (EBSD) data.
Effect of Y on Microstructure and Corrosion Resistance of AZ61 Magnesium Alloy
Authors: Xu Chun Xiang , Bai Zhi Ling , Wang Zhen Qiang , Ju Hui , Zhang Zhi Wei
Published: July 2011

The effect of Y addition on the microstructure of AZ61 alloy was investigated by optical microscopy (OM), X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The corrosion behavior of AZ61 alloy with Y addition in 3.5 % NaCl solution was studied by static weight loss and polarization curves corrosion tests. The results show that AZ61 alloy with Y addition can refine grain size of the matrix and alter the distribution of the phase β-Mg17Al12 from continuous network morphology transition to small and dispersive distribution along the grain boundary by forming the second phase Al2Y which has a high melting point. In addition, the addition of Y can decrease the corrosion current density of AZ61 magnesium alloy in 3.5% NaCl solution, thereby improving the corrosion resistance of AZ61 magnesium alloy. Results show that AZ61 magnesium alloy with 1.0% Y has the most refined microstructure and the best corrosion resistance.
Research on Tunnel Effect of Carbon Black-Filled Cement-Based Composites
Authors: Li Xiao Hui , Zhao Ran Ran , Zhang Jin Rui
Published: July 2011

Based on the tunnel effect, a mathematic model was set up to describe the tunnel resistivity of carbon black-filled cement-based composites (CBCC). The relationships between the tunnel resistivity and the microstructure parameters, the motion parameters of carriers as well as the external electric field strength in the CBCC were established by using the model. Furthermore, the inherent relation between the tunnel resistivity and carbon black volume fraction was discovered. Moreover, the effect of carbon black volume fraction on tunnel effect of CBCC was investigated through experiments. The theoretical results obtained from the model were in agreement with the experimental data, which proved the rationality of the tunnel resistivity model of CBCC.
Effects of Anisotropy on the Microstructural Characteristics and Mechanical Behavior of Shock-Loaded of AZ31 Alloy
Authors: Hao Min , Zhang Fan , Tan Cheng Wen , Su Tie Jian , Yu Xiao Dong
Published: July 2011

Effects of anisotropy on the microstructural characteristics and mechanical behavior of shock loaded of AZ31 magnesium alloy have been investigated. Using electron backscatter diffraction, tension twinning was observed in both shock loading directions along the normal (ND) and rolling directions (RD). Compression tests were carried out along ND and RD in both as-received and post-shock conditions. It indicated that the RD samples show a more notable hardening behavior compared to the as-received conditions. Moreover, it is postulated here that detwinningresults in a drop of strain-hardening rate for the ND samples under post shock reload conditions and tension twinning formed during the shock wave loading process leads to a signiﬁcant moving left of the peak strain hardening rate for the RD samples under post shock reload conditions.
The Oxidation of Co-10Cr Alloys in 1 Atm of Pure O2 at 700 and 800οC
Authors: Xiang Jun Huai , Huang Long , Zhang Hong Hua , Liu Yu Wei
Published: July 2011

The oxidation of binary Co-10Cr alloys in 1 atm of pure O2 at 700 and 800°C was investigated. It indicated that the oxidation followed approximately the parabolic rate law (n=2). The parabolic rate constants as functions of temperature were 2.03×10-11, 7.05×10-10 g2cm-4s-1, respectively. The scales formed on Co-10Cr alloys were double-layered. The outer layer composed of large columnar CoO grains was relatively compact, while the inner CoO layer was porous, fine-grained and doped by cobaltous oxide CoO and spinel CoCr2O4.
Corrosion of Amorphous Fe73.5Si13.5B9Nb3Cu1 Alloys on the Synergistic Effect of Chloride and Hydroxyl Ions
Authors: Li Ming Sheng , Zhang Dan , Jiang Yi Ming , Li Jin
Published: July 2011

The soft-magnetic properties and service life of amorphous or nanocrystalline Fe73.5Si13.5B9Nb3Cu1 have been influenced by the corrosion of the alloy. In this study, the electrochemical corrosions of amorphous Fe73.5Si13.5B9Nb3Cu1 in the blend solutions of sodium chloride and sodium hydroxide were investigated by linear polarization (PLZ) and electrochemical impedance spectroscopy (EIS) technique. The presence of OH- in the blend solution gave rise to typical passivation of the alloy. A suitable concentration of OH- was required for the low corrosion rate. And the higher concentration of OH- led to a faster corrosion. Increase of concentration of Cl- aroused more obvious corrosion. These results were ascribed to the deteriorating effect of Cl- and high-concentration OH- on the passive film formed on the surface of amorphous Fe73.5Si13.5B9Nb3Cu1.
Effect of ZnO-Loading Method on Methyl Orange Removal Capacities of Expanded Graphite/ZnO Composites
Authors: Chen Zhao Shen
Published: July 2011

Three expanded graphite/ZnO composites, marked as EG/ZnO-1, EG/ZnO-2 and EG/ZnO-3, were prepared by heating a mixture of zinc acetate and water-washed expandable graphite, dried expandable graphite and EG, respectively. The products were used for removing methyl blue (MO) in water. Under UV irradiation, the composites have the adsorption capacity of EG and the photocatalysis capacity of ZnO at the same time. ZnO-loading method influences the textural characteristics and the MO removal capacities of EG/ZnO composites. Comparatively speaking, EG/ZnO-3 is the most effective for removing MO among these composites.
Analysis of LIGA-Ni Microstructure
Authors: Liu Xiao Dong , Li Yun Kai
Published: July 2011

Micro-structure nickels were fabricated by LIGA, and their surface morphology, microstructure and texture were studied by Microscope, SEM and XRD. The results show that the specimens have uneven microstructure, and the grains are relatively small. The grains grow mainly by the form of columnar and cluster-like, and there are obviously preferred orientation in the (220) plane.
Dynamic Deformation Behavior of As-Extruded Mg-Gd-Y Magnesium Alloy and the Microstructural Evolution
Authors: Mao Ping Li , Liu Zheng , Wang Chang Yi , Wang Feng
Published: July 2011

The dynamic deformation behavior of an as-extruded Mg-Gd-Y magnesium alloy was studied by using Split Hopkinson Pressure Bar (SHPB) apparatus under high strain rates of 102 s-1 to 103s-1 in the present work, in the mean while the microstructure evolution after deformation were inspected by OM and SEM. The results demonstrated that the material is not sensitive to the strain rate and with increasing the strain rate the yield stress of as-extruded Mg-Gd-Y magnesium alloy has a tendency of increasing. The microstructure observation results shown that several deformation localization areas with the width of 10mm formed in the strain rates of 465s-1 and 2140s-1 along the compression axis respectively, and the grain boundaries within the deformation localization area are parallel with each other and are perpendicular to the compression axis. While increasing the strain rate to 3767s-1 the deformation seems become uniform and all the grains are compressed flat in somewhat. The deformation mechanism of as-extruded Mg-Gd-Y magnesium alloy under high strain rate at room temperature was also discussed.
On the Microstructure of Heat-Treated Austenitic Nickel-Base Alloy
Authors: Hao Xian Chao , Chen Bo , Ma Ying Che , Liu Kui
Published: July 2011

A series of heat treatments were preformed to study the evolution of microstructure in an austenitic nickel-base Alloy 690 using optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that the pre-existed chromium carbides of cold-rolled Alloy 690 were dissolved into the austenitic matrix after high temperature mill annealing (MA) at 1353K for 5min. Mill-annealed and thermally treated Alloy 690 had intergranular M23C6-type carbides. The morphology of intergranular M23C6 varied from continuous, semi-continuous to discrete with the temperature of thermal-treatment (TT) increasing from 873K to 1073K. The holding time at temperature of 988K had less influence on the intergranular carbide appearance than that of temperature. The minimum chromium concentration in the vicinity of intergranular carbides was 22.3 wt% in the sample thermally treated at 715°C for 2h. With the holding time of TT increasing from 2h to 27h, Cr concentration increased gradually and the chromium depletion became wider.
Relation between Impact Properties and Interfacial Strength of UHMWPE/VE Composites
Authors: Min Chun Ying , Song Hao Jie , Han Peng , Chen Lei , Liu Liang Sen
Published: July 2011

This study presents impact properties and interfacial strength of Ultra-high molecular weight polyethylene fiber plain woven fabric reinforced vinyl ester composites with different matrix volume fraction. The interfacial strength was found to be decreased by reducing the matrix volume fraction. Stress, strain and energy absorption per thickness in the impact process were evaluated and the relation between these impact parameters and interfacial strength of the laminates were investigated. The maximum stress was decreased and the maximum strain was increased with the drop of interfacial bonding strength. The experiment results also revealed that the sample with a matrix volume fraction 23% showed higher energy absorption than other ones.
Effect of Cerium on Microstructure and Wearing Resistance of 5CrMnMo Hot Working Die Steel
Authors: Hao Xin , Pan Mei Ling , Liu Xiao Fei
Published: July 2011

The microstructure and wearing resistance of 5CrMnMo hot working die steel with four different amounts of additions of Ce was studied and compared with that without Ce by analyzing the microstructure, worn-out appearance, average wearing rate and friction coefficient. The results showed that when the addition of Ce was proper, the microstructure was significantly refined, the average wearing rate and friction coefficient were reduced markedly and the grinding crack image was also relatively thin and shallow. Therefore, the wear resistance was improved effectively. When the addition of Ce is 0.20 %( mass percent), 5CrMnMo steel had the least surface average wearing quantities and the best wearing resistance. As compared with the 5CrMnMo steel without Ce, the average wearing rate decreasing margin of that with 0.20% Ce was high to 36.19%.
Effect of Thermo-Mechanical Heat Treatment on Microstructure and Mechanical Property of 2197 Al-Li Alloy
Authors: Mao Bai Ping , Li Jun Peng , Shen Jian
Published: July 2011

Effects of thermo-mechanical treatment on the mechanical properties and microstructure of 2197 alloy were studied through analyses of the mechanical properties by tensile tests and TEM observation of thermo-mechanical heat treated 2197 alloy plates of various states. Results show that the dominating precipitated phase of peak-aged 2197 alloy during thermo-mechanical heat treatment is T1 phase of which the size is 50~150nm. The precipitation and growth of T1 phase are accelerated due to the existed nucleation sites for heterogeneous nucleation of T1 phase offered by thermo-mechanical treatment, therefore, the time for 2197 alloy to reach the peak-aged state is shorten. The strength of 2197 alloy for peak-aged state is increased through thermo-mechanical treatment because the strengthening effect of T1 phase with higher aspect ratio is bigger than that of δ′ and θ′ phases.
Influences of Complex Modification of RE and P on the Wear Resistance of Hypereutectic Al-24Si Alloy
Authors: Liu Niu Can , Li Jun Qing , Li Hai Dong
Published: July 2011

The influences of RE and P complex modifications on microstructures and wear-resistance of hypereutectic Al-24Si alloy were studied. The results show that the complex modifications of P and RE make the coarse block primary crystal silicon refined and their edges and angles are passivated, the large needle-like network eutectic silicon be modified to the fine lamella or particle ones. The optimum modification effect occurs with 0.10%P and 0.9%RE. The complex modification of P and RE can also obviously improve wear resistance of hypereutectic Al-24Si alloy. When the tested alloys modified with 0.10%P and 0.9%RE, the optimal wear resistance of modified alloys is obtained. The weight loss is decreased to 3.9mg from 5.4mg of the unmodified alloy, decreased by 27.8%. The abrasive wear caused by the breaking of Si phase is dominant wear mechanism of the alloy. It can be attributed to the refinement of primary silicon and eutectic silicon particles and the increase of strength and ductibility of alloys caused by the complex modification of P and RE.
Joining Aluminium to Titanium by MIG Welding-Brazing Process
Authors: Chen Bo , Zhang Hong Tao , Jiang Wen Jie
Published: July 2011

With Al-Si welding wire ER4043, lap joint between aluminium and titanium alloy was made by MIG welding-brazing process with nocolok flux aiding filler metal in promoting metal wettability. A thin intermetallic compound layer was formed at the interface between the weld metal and titanium alloy and the layer mainly consits of TiAl3 phase. The tensile strength of the joint can reach 151MPa and fracture occurred in aluminium base metal.
Effect of Quenching on the Corrosion Morphology of Al-Zn-Sn-Ga Anode Alloy
Authors: Wen Jiu Ba , Li Jun Fen , He Jun Guang , Ma Jing Ling
Published: July 2011

In this paper, the Al-Zn-Sn-Ga anode alloy was quenched from 460 °C. The influences of corrosion time and different microstructure of the alloy on its corrosion morphology were investigated to clarify the effect of quenching on the corrosion morphology of the alloy. The inhomogeneous composition in the as-cast alloy directly caused various corrosion potential in the alloy and that the driving force of corrosion was different. Lots of circular corrosion pits and basic uniform composition were observed in the quenching sample. The results reveal that the corrosion morphology of the anode alloy is affected by quenching treatment employed.
Study on Regeneration Ability of Oxidation Film on Ignition-Proof Magnesium Alloy Added with RE
Authors: Deng Zheng Hua , Li Hua Ji , Li Wei Bin
Published: July 2011

The ZM5-0.1%RE magnesium alloy was heated to 800°C, when the surface oxide film was formed, the ZM5-0.1% RE Magnesium alloy which had being oxidized obtained by removing the surface oxidation film on the ZM5-0.1%RE magnesium alloy at room temperature. TGA curve, oxidaxion kinetics curves at constant temperatuers of the alloy and XRD spectrum of the surface film were analyzed in order to investigate the sureface oxidation behavior.The results show that the alloy still has anti-oxidation performance, And the oxide inerease occurred mostly between 400°C and 700°C，a layer of tight oxide film with 4-5.5um and composed of RE2O3, MgO, Al2O3 and Mg17Al12 was formed on the surface of magnesiurn alloy. The tight surface oxide film prevented the further oxidation of the base magnesiurn alloy, It show that the regeneration ability of oxidation film on ZM5-0.1%RE Magnesium Alloy was good.
Effects of Bi on Mechanical Properties of Magnesium Alloy AZ81
Authors: Li Quan An , Zhang Qing , Li Chang Qing , Wang Yao Gui
Published: July 2011

The effects of bismuth on the mechanical properties of magnesium alloy AZ81 have been investigated. The results show that the addition of 1wt.% bismuth can improve the morphology of β-Mg17Al12 phase, cause the formation of Mg3Bi2 phase, and enhance the mechanical properties of magnesium alloy AZ81 at room temperature and 150°C.
Preparation and Characterization of PMMA-b-PDMAEMA/Polysulfone Composite Membranes by RAFT Polymerization and their Permeation Performance of Carbon Dioxide
Authors: Shen Jiang Nan , Ye Yun Fei , Zeng Gan Ning , Qiu Jun Hong
Published: July 2011

PMMA-b-PDMAEMA/polysulfone composite membranes for CO2 separation was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization techniques. The chemical composition and structure of the polymers were characterized by Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR), and molecular weight and its distribution were measured by Gel permeation chromatography (GPC). CO2 permeation performance of the PMMA-b-PDMAEMA/ polysulfone composite membranes was test. The results showed that the resulted composited membrane posses good permeation performance for CO2.
Effect of ZnO-Loading Method on Adsorption and Decomposition Capacities of Expanded Graphite/ZnO Composites for Crude Oil
Authors: Yue Xue Qing
Published: July 2011

Three expanded graphite/ZnO composites, marked as EG/ZnO-1, EG/ZnO-2 and EG/ZnO-3, were prepared by heating a mixture of zinc acetate and water-washed expandable graphite, dried expandable graphite and EG, respectively. The adsorption capacity of the composites for spilled crude oil was measured, and under UV irradiation, the decomposition of the absorbed crude oil was investigated by oil weight loss method. The results show that the composites have adsorption and photocatalysis capacity for crude oil at the same time, and the adsorption and photocatalysis capacity are influenced by ZnO-loading method.
Two Step Synthesis of Hydroxyl Group Polyimide Based on 2,2-Bis(Amino-4-Hydroxyphenyl)hexafluoropropane
Authors: Zheng Yan Hong , Wang Lian Cai , Zhai Yu , Guo Bao Hua , Zeng Xin Miao
Published: July 2011

The feasibility of using two step procedures with thermal imidization of polyamic acid (PAA) for synthesizing hydroxyl group polyimide (PI), based on 2,2-Bis(3-amino-4-hydroxyphenyl)hexafluoropropane (Bis-AP-AF), was studied. It was found that a high molecular weight PAA could be successfully synthesized from Bis-AP-AF with 3,3',4,4'-Benzophenone tetracarboxylic dianhydride (BTDA). The optimum polycondensation reaction time on synthesizing molecular weight of the PAA was 4 hours. The PI films could be successfully prepared by thermal imidization of the PAA. The higher the inherent viscosity of the PAA is, the more beneficial for the tensile properties of the PI films. All the results indicate that two step procedures with thermal imidization of the PAA under appropriate conditions represented a promising way for preparation PI films, with a reasonable level of mechanical properties.
Release of Anticancer Drug Doxorubicin from Biodegradable Polymer Coated Porous Hydroxyapatite Scaffolds
Authors: Pelss Juris , Loca Dagnija , Berzina-Cimdina Liga , Locs Janis , Lakevics Vitalijs
Published: July 2011

In the current research slow release anticancer drug delivery system was prepared and drug release kinetics in vitro evaluated. Porous hydroxyapatite (HAp) as carrier material and doxorubicin hydrochloride (DOX) as anticancer agent was used. DOX is an anthracycline drug commonly used in cancer chemotherapy. Unfortunately, its therapeutic potential is restricted cardiotoxicity and resistance developed by the tumor cells to the molecule after treatment. To prepare HAp-DOC composites, the porous bioceramic scaffolds were impregnated with doxorubicin in low vacuum conditions. 10% (HAp-10%PLA) and 20% (HAp-20%PLA) poly lactic acid and 20% (HAp-20%PCL) poly(e-caprolactone) solutions in dichloromethane were used to form the polymer coatings on the drug/bioceramic composites. In general there was a burst release observed from all the samples during the first 2 hours followed by a much reduced release profile. In the next 5 days the drug release from all the samples decreased in the following order: 20% PLA (from 56 ng/ml to 3 ng/ml), 20% PCL (from 196 ng/ml to 6 ng/ml), 10% PLA (from 497 ng/ml to 18 ng/ml). HAp-DOX composite without the polymer coating demonstrated the drug release reduction from 230 ng/ml to 13 ng/ml. The cumulative drug release was observed over 19 days.
Preparation and Characterization of Nano-TiO2/PE Antibacterial Films
Authors: Li Hui , Wan Ji , Dang Wei Hua
Published: July 2011

A kind of endurant antibacterial PE films were prepared by using Nano-TiO2 modified by JH-3112 silane or titanate coupling agents. The optimum amount of modified TiO2 in PE substrate was concluded from the comprehensive performances of TiO2/PE films. The antibacterial properties of Nano-TiO2 and Nano-TiO2/PE films were studied respectively. It was indicated that antibacterial abilities of Nano-TiO2/PE films dramatically increased as comparing with PE films without TiO2.
High Temperature Resistance of Epoxy Adhesives under the Room-Temperature Curing
Authors: Ran De Long , Xie Jian Jun , Huang Kai , Yin Shui Ping , Chen Sheng Ming , Luo Ying She
Published: July 2011

High-temperature resistant epoxy adhesives cured under room-temperature becomes more and more important in many industries such as aerospace and aviation, the locomotive and diesel, etc. In this paper three self-made amine-based mannich-amide was mixed with E-44 epoxy resin under the same technological parameters, and the epoxy adhesives cured by the three amine-based mannich-amides under room-temperature are tested by FTIR, TGA and DMA. Results of TGA show a quicker drop in weight occurrence within 150-250°C for epoxy networks cured by multiamine-based mannich amides than the long-chain alkyl one. Results of FTIR show completely curing of epoxy adhesives cured by mannich amides under room temperature and the height of absorption band 1502cm-1 (C-N) is much lower after 12h under 150°C,200°C atmosphere than 25°C. Results of DMA show that the Tg determined by DMA has an order EP AN2(89.9°C) >EP AN1(89.7°C)>EP AN3(80.8°C). In the rest results of DMA, the EP-AN3 system has the biggest storage modulus (E’) within 100-150°C while the EP-AN3 system has the smallest loss modulus(E”) within 100-150°C. As a whole, the epoxy adhesives cured by AN3 under room-temperature have the best high temperature resistance.
Investigation on the Alkali-Resistance Properties of Basalt Fiber Reinforced Plastics Bars in Concrete
Authors: Zhou Jun Long , Xu Chun Xia , Jiang Shi Yong , Li Bing Hong , Ou Zhong Wen
Published: July 2011

As a new type of building material, Basalt Fiber Reinforced Plastics is employed in concrete in place of steel reinforcement under such strongly-corrosive environment as marine engineering projects to avoid durability problem caused by corrosion. But BFRP bars’ alkali-resistance must be considered and studied. In this study, BFRP was soaked in saturated Ca(OH)2 solution and its tensile strength was measured through long-period immersion and high-temperature immersion experiments respectively. Besides, accelerated high-temperature method was adopted to detect its main ingredients: continuous Basalt fiber and resin. The results indicate that BFRP has poor alkali-resistance and its alkali-resistance must be improved if it is applied in concrete for long-term purpose.
Synthesis of Carbazoled Poly(Arylene Imino)
Authors: Shan Wen Wen , Chang Guan Jun , Zhu Fang Hua , Zhang Lin
Published: July 2011

The carbazoled poly(arylene imino)s (c-PAI) have been synthesized via palladium-catalyzed polycondensation of 3,6-diamino-N-(2-ethylhexyl)carbazole with different aromatic dibromides. The structure of c-PAI were characterized by means of FT-IR, 1H NMR spectroscopy and elemental analysis, the results show an agreement with the proposed structure. The thermal properties of c-PAI were detected by DSC and TG. The result show that the polymers possess high glass transition temperature (Tg＞250°C ), good thermal stability with high decomposition temperatures (TD＞410°C), In addition to the thermal properties, the optical properties were studied, including Uv-vis absorption, photoluminescence and time of flight (TOF).
Studies on the Solubility of Bonded-Rare Earth Complexes and Fluorescence Properties of their Copolymers
Authors: Sheng Wei Chen , Wei Wei , Tan Jing , Zhou Zhi Ping , Song Hao Jie
Published: July 2011

A binary and ternary rare earth complexes were synthesized. The structure and composition of the complexes were characterized by FT-IR and Elemental Analyzer. It is found that the complexes have excellent fluorescence intensity and thermal stability. Photoluminescent measurements show that Phenanthroline (Phen) could efficiently transfer energy to Eu3+ and sensitize the luminescence of Eu3+. The copolymers of complexes, methyl methacrylate (MMA) and methacrylic acid (HMA) emit characteristic fluorescence of Eu3+. The fluorescence intensity enhanced with the complexes content increasing. But the apparent copolymers of Eu(AA)3 have stronger luminous intensity than that of Eu(AA)3Phen under limit solubility because Phen reduces the content of solvable Eu3+ in the mixture of MMA and HMA.
Isothermal Crystallization Kinetics of Poly (Phenylene Sulfide)/TiO2 Composites
Authors: Zhang Zhong Hou , Cao Guang Xiu , Li Ying Ying , Yan Chun Mian
Published: July 2011

Poly (phenylene sulfide) (PPS)/nano-TiO2 composites were prepared by DAKA miniature blending instrument. Isothermal crystallization behavior of PPS composites at 245°C, 250°C, 255°C and 260°C were investigated by means of DSC. The crystallization time of PPS composites is shorter than which of neat PPS at the same crystallization temperature. The Avrami equation was used to analyze DSC data. Results showed that neat PPS is homogeneous nucleation at lower crystallization temperature, which is heterogeneous nucleation at higher crystallization temperature contrarily. PPS/nano-TiO2 composites are heterogeneous nucleation at various crystallization temperature, nano-TiO2 particles play a role of nucleating agent.
Synthesis and Characterization of Glucose and Acrylamide Copolymer
Authors: Xie Yue Sheng , Wang Wei , Tan Wen Bo
Published: July 2011

The copolymerization reaction between glucose and acrylamide was initiated using Ce(NH4)2(NO3)6 as initiator under microwaves heating at 60~80°C. The product is glucose-acrylamide copolymer. The synthesis experiment shows that the copolymerization was initiated quickly when the dosage of glucose is 2~30%. When the optimal dosage of glucose is 20%, the average rate of acrylamide and glucose is 10∶1 in the long chain of the copolymer molecule; the average molecular weight of the copolymer is 3.61×108. The flocculating test showed the water-solubility of the copolymer is better than polyacrylamide, and with the same flocculating effect. The copolymer will easy to be biodegraded because that with amount of the glucose in its long chain molecules.
Effect of Amphoteric Acrylic Retanning Agent on the Physical Properties of the Resultant Leather
Authors: Jin Li Qiang , Wang Yu Lu , Zhu De Yi , Xu Qing Hua
Published: July 2011

The unique physical properties of leather make it ideally suited for the manufacture of a variety of products. Retanning has important effects on the mechanical and physical properties of the resultant leather. In this paper, a novel amphoteric acrylic copolymer as retanning material was prepared by free radical copolymerization. The effects of this copolymer on the physical properties of the resultant leather have been investigated by measuring physical and mechanical indexes of the retanned leather. The function mechanism of this copolymer was also researched. Results showed that this copolymer could improve the properties of the resultant leather including softness and strength, and increase leather’s dyeability in contrast to anionic acrylic polymer.
Effect of Preparation Technique on Methyl Orange Sorption Behavior of Exfoliated Graphite
Authors: Chen Zhao Sheng
Published: July 2011

Three natural graphite flakes (35, 50 and 80 mesh) were used as raw material. Exfoliated graphite (EG) was prepared by rapidly heating expandable graphite to 1000 °C in a muffle and by irradiating it in a microwave oven with a power of 280 W for 40 s, respectively. The EG samples were used for removing methyl orange (MO) from aqueous solution. The effect of preparation technique of EG (particle size of natural graphite and exfoliation method of expandable graphite) on MO removal properties was investigated, and a higher removal rate was achieved.
Experimental Study on the Anti-Permeability Properties of Polymer Grouting Materials
Authors: Wang Fu Ming , Shi Ming Sheng , Li Hui Jie , Zhong Yan Hui
Published: July 2011

The polyurethane foam as a representative nonaqueous reacted polymer grouting material has become one kind of advanced comprehensive performance material, and therefore it is necessary to research on its anti-permeability properties. According to impermeability grade method, polymer grouting materials are tested under different initial pressures and different densities. The results indicate that the density of polymer materials is generally at the range of 0.1g/cm3～0.3g/cm3 and the initial seepage pressure is at the range of 0.3～0.7MPa, which can bear 30 to 70 meters head pressure when seepage grouting is carried out in hydraulic engineering. According to the actual needs of different projects, polymer grouting amount is controlled to regulate the density of polymer materials to meet the need of different projects impermeability.
Preparation and Magnetic Properties of the Core-Nanoshell Composite Materials Doped with Nd
Authors: Che Ru Xin , Wang Chun Xia , Yu Bing
Published: July 2011

The core-nanoshell composite materials doped with Nd 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 Nd. The thermal decomposition process of the sample was investigated by TG- DTA. 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 ( VSM ) analysis indicated that the exchange-coupling interaction happens between ferrite of magnetic fly-ash hollow cenosphere and nanosized ferrite coating. The exchange-coupling interaction enhances magnetic loss of composite materials. The results show that doped with Nd can enhance the coercivity too, so the magnetic properties could be promoted further. The magnetic properties of the core-nanoshell composite material are better than that of single-phase.
Effect of Surface Treatment for Carbon Nanotubes on Morphological and Rheological Properties of Polyarylene Ether Nitriles Nanocomposites
Authors: Zhan Ying Qing , Meng Fan Bin , Zhao Rui , Liu Xiao Bo
Published: July 2011

Poly(arylene ether nitriles) (PEN) nanocomposites containing various functionalized multi-walled carbon nanotubes (MWCNTs) were prepared through solution-casting method. The as-prepared PEN nanocomoposites were investigated by parallel-plate rheometer, aiming at examining the effect of surface functionalizaion on the dispersion of MWCNTs by using viscoelastic properties. The results of linear viscoelasticy indicated that the 4-aminophenoxyphthalonitrile-grafted MWCNTs (MWCNTs-CN) presented better dispersion in PEN matrix than purified and carboxylic MWCNTs because of the corresponding composite showed the lowest rheological percolation threshold, which was further confirmed by morphological observation. Both the dispersion state and the surface functionalization of MWCNTs are very important to the rheological behaviors of PEN matrix.
Modeling Radial Variation in Microfibril Angle of Scots Pine
Authors: Li Yao Xiang , Jiang Li Chun
Published: July 2011

Microfibril angle (MFA) was determined at each growth ring from disks at breast height (1.3 m) from four scots pine (Pinus sylvestris) trees grown in northeastern China. Significant variation in microfibril angle was observed among growth rings. MFA at breast height showed a decreasing trend from pith to bark for each tree. The modified logistic model with nonlinear mixed-effects was used for modeling earlywood MFA. The NLME procedure in S-Plus is used to fit the mixed-effects models for the MFA data. The results showed that logistic model with two random parameters and could significantly improve the model performance. The CS, AR(1), MA(1), and ARMA(1,1) correlation structures were incorporated into mixed-effects models. The mixed model with the AR(1), MA(1), and ARMA(1,1) correlation structures improved model performance (P<0.0001).
Preparation and Characterization of Al2TiO5- Si3N4 Composites by Reaction Sintering Process
Authors: Wang Rui Sheng , Zhao Jun Hong , Wei Heng Yong , Yao Shao Wei
Published: July 2011

Al2TiO5-Si3N4 composites were prepared by reaction sintering process using Al2TiO5 and α-Si3N4 powders as raw materials. The effect ofsintering temperature, soaking time and Si3N4 content on the sintering properties of the composites was studied. The results showed that the best sintering temperature and soaking time were 1550 °C and 2 h, respectively. The samples with 15 wt% of Si3N4 addition had good sintering properties, and its mechanical strength was 28.96 MPa, which was 2 times of the one of the samples without Si3N4 addition.
The Spin-Dependent Electronical Conductivity of Polarons in the Spin Polarized Organic Semiconductor
Authors: Zhao Xiao Qing , Mi Yi Lin , Liu Feng Yan
Published: July 2011

The spin-dependent electronical conductivity of polarons is studied in the spin polarized organic semiconductor .It is found that the spin dependence of the electronical conductivity is induced by the spin polarization of the organic semiconductor, for the spin polarization makes the up-spin and the down-spin polarons have different density, which generates the spin-dependent electronocal conductivity. The spin-dependent electrical conductivity can be directly affected by the match level of conductivities s0/sf at the interface of the FM/OSE. Moreover, the current spin polarization in the organic semiconductor can be strengthened by the electric-field in the low-electric-field region .
A Method of Reducing Volatile Compounds in Polypropylene Packaging Materials
Authors: Li Dong Li , Xu Wen Cai , Fu Ya Bo
Published: July 2011

When food contamination problems occur, one of the first priorities is adsorption to any volatile or semivolatile organic chemicals in packaging materials. In this contribution the adsorption behaviour of modified polypropylene composites containing nano-silica is reported. The nano silica can increase the polarity of PP and decrease more volatile solvent residue of ethyl acetate in CPP film. If lower volatile solvent used in print ink or adhesive, load of nano silica can decrease solvent residue too, when a lesser decrease is happen in crystallinity of modified PP. The nano modification process is able to produce more safe food packaging materials, but must consider the load of nanosilica.
A Study on the Photolysis Behavior of Photoacid Generators
Authors: Zhang Wei Min , Wang Wen Guang , Pu Jia Ling
Published: July 2011

A method for evaluating the photolysis behavior of photoacid generator in solvent and high polymer film has been established through spectrophotometry and fluorospectrophotometry by using the acid-sensitive Rhodamine B as tracer. Results showed that this method is feasible and practicable for evaluating the acid generating efficiency of photoacid generator in organic solvents or polymer film, yielding quantitatively precise data of the photochemical reaction and acid generating behavior, thus is very useful for evaluating the quality of different types of photacid generators e.g. triazines, sulfonium salts etc.
Investigation on Direct Electrolytic Reduction of the CaTiO3 Compounds in Molten CaCl2-NaCl for the Production of Ti
Authors: Lang Xiao Chuan , Xie Hong Wei , Zou Xiang Yu , Kim Pyong Hun , Zhai Yu Chun
Published: July 2011

The CaTiO3 compounds were prepared by sintering the mixtures of the TiO2 and CaO in air. The compounds were used as cathode, the graphite as anode and the molten CaCl2-NaCl as electrolyte. Electrolysis was performed at 800°C and constant-voltage 3.2V in dry argon atmosphere. The results showed that the electrolytic rate could be significantly enhanced because of the additive CaO. The electrolysis time was shortened efficiently than that of direct electrochemical reduction of solid TiO2.
CO2 Adsorption Performance of N-Doped Ordered Microporous Carbons Templated from Zeolite HY
Authors: Zhou Jin , Li Wen , Zhuo Shu Ping
Published: July 2011

Several microporous carbons were prepared by a two-step method using zeolite HY as a template, and were used as CO2 adsorbents. X-ray diffraction patterns present that the structure regularity of the zeolite has been well-replicated by the templated carbons. X-ray photoelectron spectroscopy confirms that the prepared carbons possess abundant nitrogen-containing groups due to the carbon deposition of acetonitrile. The prepared carbons show high CO2 adsorption capacity due to its very high microporous surface area and abundant basic nitrogen-containing groups.
Experimental Study on the Fire Characteristics of Indoor Combustible Materials
Authors: Zheng Yan Min , Zhang Jin Feng , Dong Wen Geng , Zhang Jun Hui
Published: July 2011

Through the pyrolysis experiments of the building room’s common combustible materials in this paper, the weight loss curves were obtained and the kinetic parameters of these three substances - activation energy and pre factor were got on which based the thermal kinetics analysis. While the reaction properties of materials were obtained by the smoldering experiments with different heat flow on a certain degree，with the increase of the heat flow, the temperature and time curve offset to the left. This is also consistent with the result of pyrolysis experiment. To some extent, this will laid a theoretical foundation for the building interior materials handling fire.
Preparation and Study of Polyethylene Glycol (PEG)/Titanium Dioxide (TiO2) Phase Change Materials
Authors: Kang Hai Yang , Li Gui Juan
Published: July 2011

This paper adopted the general method of sol-gel to prepare a list of PEG/TiO2 phase change materials (PCMs). The chemical structure of the materials was investigated by FT-IR respectively. The infrared indicate that the materials have good chemical compatibility. The thermal properties of the samples were measured by differential scanning calorimetry(DSC) and thermogravimetry(TG). The surface topography and crystallized behavior of the materials were detected by SEM and XRD. The TG thermographs show the samples can sustain high temperature about 212°C. The DSC measurements display that the phase change temperature of the materials’ range from 52°C to 56°C. The results obtained from experiments show that the phase change materials possesses a good potential as a thermal energy storage material.
Identification of White Light Emission with Two Complementary Colors in Organic Light-Emitting Devices
Authors: Wang Jun , Jiang Ya Dong , Yu Jun Sheng
Published: July 2011

Simple method of determining emission light color in organic light-emitting diodes (OLEDs) with two emissive materials from their electroluminescent (EL) spectra has been presented. The Commission Internationale de l'Eclairage (CIE) coordinates and two EL intensity rates of OLEDs can be simulated with this method. White light OLEDs were fabricated with a blue light emission from 4,4'-bis[N-1-napthyl-N-phenyl-amino]biphenyl (NPB) and a yellow light emission from bis[2-(4-tert-butylphenyl)benzothiazolato-N,C2’]iridium (acetylacetonate) [(t-bt)2Ir(acac)], and the device shows the CIE coordinates of (0.34, 0.32) at 10 V bias, which located in white light region.
Study on Phase Composition of Long Persistence Phosphors SrAl2O4:Eu2+,Dy3+Synthesized by Combustion Synthesis Method
Authors: Sun Wen Zhou , Chen Yu Hong , Han Fei , Jiang Liang
Published: July 2011

SrAl2O4:Eu2+,Dy3+ long persistence phosphors are synthesized by combustion method. The effects of several processing conditions such as the mole ratio of urea and metal nitrates, initiating temperature, the amounts of fluxing agent(boric acid), and raw material ratio（Sr:Al）on phase composition and subsequent on the spectroscopic properties are studied. The results show that the phase composition changed from strontium-rich phase to aluminium-rich phase with the increasing of initiating temperature, the increasing of the content of urea and boric acid, and with the decreasing of Sr:Al. The results indicate that the sample has most excellent luminescence performance is not the one which has pure single phase SrAl2O4, but the one has little impurity phase SrAl4O7. Similar phenomenon is also present when synthesized by high temperature solid-state method and microwave plasma synthesis method, so the differences among three methods are also discussed in this paper.