bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties Investigation of Yb3+-Doped Phosphate Glasses for Fiber Laser
Authors: Yang His Wen , Zhu Jin Ming , Tsai Yu Xiang , Lin Chun Hsiung , Hsu Cheng Hsing , Lai Chun Hung , Lee Yi Mu
Published: September 2013

The physical and optical properties of P2O5-Al2O3-ZnO glasses doped with different concentration of Yb3+ions were investigated. The experimental results indicated that density, chemical durability, glass transition temperature (Tg) and glass softening temperature (Td) of glasses increase with increasing the Yb2O3content of glasses. However, the coefficient of thermal expansion (α) for glasses decrease with increasing the Yb2O3content. From the results of Fourier transform infrared spectroscopy, the numbers of (-P-O-P-) bonds decrease and (-P-O-M+-) bonds increase with increasing the Yb2O3content. Increase of non-bridge oxygen (-P-O-M+-) raise the refractive index of glasses. Moreover, the results of absorption spectra indicate that the absorption peak of glasses are observed at both wavelengths of 916nm and 977nm. As increasing the concentration of Yb2O3, the absorption efficiencies become stronger. In accordance with the results of fluorescence spectra, the fluorescence emission of glasses are detected at wavelengths of 970nm, 995nm, 1020nm and 1048nm, respectively. The intensity of the fluorescence emission peaks significantly decrease at wavelengths of 970nm and 995nm as the concentration of Yb2O3increases. However, the intensity of the fluorescence emission peaks significantly increase at wavelength of 1048nm under the same condition.
The Microstructure Evolution and Control of Alloy 690 during Cold Rolling
Authors: Yao Zhi Hao , Dong Jian Xin , He Zhi Yong , Zhang Mai Cang
Published: September 2013

The microstructure evolution and control for Alloy 690 during cold rolling and annealing treatment was investigated. Cold rolling specimens were deformed in the strain range from 15% to 70% with strain rates from 0.01 to 10s-1. Subsequent annealing treatment was carried out in the range of 1060~1100°C for dwell time 3~15mins. Rolling reduction, annealing temperature and annealing time except strain rate had obviously influence on grain size and hardness. Little coarsening of grains were observed below 1060°C during annealing treatment, whereas grains coarsened obviously over 1080°C. Besides, the behavior of grain growth for alloy 690 was investigated systematically.
Problems and Suggestions of Chinese Highway Bridge Seismic Design
Authors: Gao Xiu Yun , Zhang Shao Yi
Published: September 2013

The seismic design of Chinese Highway Bridge changed from single standard of fortification and one-step design performed nearly two decades to two-level fortification and two-stage design with the introduction of the new codes in 2008 and 2011. However, there are some shortcomings of the new codes such as the choice of response spectrum type, the determination of reinforced concrete constitutive relation, the discrimination of site-type and the bearing checking items, which leave a large room for improvement. Combined with the design codes of the developed countries like Japan and the United States, some useful suggestions are put forward in this paper for Chinese existing design codes. It is believed that Chinese seismic levels can be significantly increased so long as highway bridges are designed in accordance with the improved codes.
Dynamic and Mitigation Analysis of Seismic Pounding Effect on Multi-Span Highway Bridges Subjected to Spatial Earthquakes
Authors: Li Yong , Zhao Liang , Sun Hang , Liu Jing Bo
Published: September 2013

The main girder and the piers of bridges are generally linked with sliding bearings. Under seismic excitation, pounding effects between the main girder and the abutment, the adjacent girder and the blocking device caused by excessive relative displacements between piers, abutments and the girder are highly probable. The effects can not only damage the structure but also lead to collapsing. Based on a continuous viaduct, the paper studied the disciplines of the pounding response under uniform seismic excitation and the spatial seismic excitation, then put forward that the composite metal damper may reduce the effect of pounding. The research shows that under same seismic intensity, the results, including pounding force, the shear force of the fixed bearings and the plastic hinge on the piers, are amplified under multi-point excitation than under uniform excitation. And composite metal dampers can reduce the seismic responds under frequent earthquakes and prevent or largely reduce the pounding effect under severe earthquakes. Therefore the effect of pounding on the dynamic performance can be lessened. The seismic reduction is widely and well-adapted under both uniform excitation and multi-point excitation.
Predicting Polyurethane Shape Memory Behaviors in Stress-Controlled Situations Using a Viscoelastic Model
Authors: Wang Zhao Jing , Luo Ling , Jia Yu Xi , Gao Jun Peng , Yi Xiao Su
Published: September 2013

As an outstanding class in smart materials of particular interest, shape memory polymers (SMPs) and their composites are drawing more and more attentions due to their potential applications in fields like biomedical and spacecraft industry. In this paper, shape memory behaviors of polyurethane (PU) in stress-controlled situations are simulated on the basis of the generalized Maxwell model and the time-temperature superposition principle. The free recovery cycles under three different imposed stresses and the influence on shape memory behaviors caused by changing heating rate are discussed. As the results reveal, the generalized Maxwell model can be used to describe the PU shape memory performance, and the shape recovery temperature increases with the increase of heating rate.
Adsorption of Benzene and Aniline Using a Novel Hypercrosslinked Polymeric Adsorbent Modified by Phenolic Hydroxyl Group
Authors: Yuan Xin Hua , Guo Wen Hua , Lei Yan , Liu Yong Qiang , Wu Ji Ye , Qiu Wei Qun , Hu Jie , Cao Shun Sheng
Published: September 2013

Using gelatin as dispersant, liquid paraffin as porogen, novel hypercrosslinked polymeric adsorbents of LM-5 and LM-6 were prepared by post-crosslinking reaction with phenol and 2-naphthol, respectively. Bromoethane was used as crosslinking reagent to substitute poisonous organic compound of chloromethyl methylether. 2-Naphthol was used in the post-crosslinking reaction to enhance phenolic hydroxyl group content. The experiments of selective adsorbing aniline on resins in mixture solution, which consisting of benzene and aniline, show that the adsorption of aniline and benzene on LM-6 in aqueous solution are mainly pushed by physical interaction. The adsorption of aniline is also partly pushed by chemical interaction, and the adsorptive enthalpy illuminates that there exists hydrogen-bonding. Owning to the hydrogen-bond, the adsorption capacity of aniline on LM-6 is markedly higher than that of benzene.
Polyacrylonitrile Based Carbon Fibers Obtained from a Melt Spun Route
Authors: Wang Yan Zhi , Wang Shu Gui , Liu Jia Lin
Published: September 2013

Polyacrylonitrile (PAN) copolymers containg photocrosslinkable comonomer were obtained by the free-radical suspension copolymerization of Ultraviolet photocrosslinkable comonomer (UPC), methyl acrylate (MA) and acrylonitrile (AN) that was carried out in DMSO/H2O using redox as initiator in which have a typical composition of AN/MA/UPC in the mole ratio of 84/15/1. It was shown that MA was found to be suitable for enabling the melt processing of PAN. The ultraviolet sensitivity of UPC moiety improves the ultraviolet crosslinkability of the precursor fibers, as a result, the melt spun precursor fibers after ultraviolet irradiated can be oxidatively stabilized at 310 oC without melting and subsequently carbonized. The resultant carbon fibers with tensile strength of 602.2±151.3 MPa and modulus of 7.32±0.78 GPa were obtained.
Synthesis of AlN-SiC Ceramics by Hot Pressing
Authors: Zhou Li Juan , Zhao Yun Xia , Meng Fan Tao
Published: September 2013

AlN-SiC ceramics were prepared at 1950°C by hot pressing (HP) of AlN/SiC powders in stoichiometric proportion. The sintered product was characterized using X-ray diffraction (XRD). Scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS) were utilized to investigate the morphology characteristics. The results show that AlN-SiC phase is well-developed with a close and lamellar structure. The grains are plate-like with the size of 1-3μm, the thickness of 3-5μm and elongated dimension. The results showed that the products had the density of 99 percent of the theoretical, bending strength of 550-800 MPa and fracture toughness of 5-6 MPa·m1/2. The distribution of AlN-SiC grains is relatively uniform.
Comparison of Mechanical and Frictional Properties of PTFE Matrix Composites Reinforced by Different Fibers and Graphite
Authors: Xu Hong Xing , Yuan Xin Hua , Zhu En Bo , Li Shuang Lian , Chen Ling , Han Zhi Rui
Published: September 2013

The polytetrafluoroethylene (PTFE) matrix composites which filled with polyphenylene sulfide (PPS) fiber, poly-p-phenelenferephthalamide (PPTA) fibre or glass fiber (GF)) and graphite at various mass fractions were prepared by the processes of mechanical blending, compression molding and sintering. The mechanical properties of the composites, such as tensile strength, impact strength and hardness were investigated. The results show that tensile strength and elongation at break markedly decrease but elasticity increases by filling with fibers. Impact strength decreases by filling with PPS and GF, and the composite displays brittle characteristic. However, the impact strength rapidly increases by filling with PPTA fiber. Hardness increases with the fibers content increases, and decreases with graphite content increases. Filling graphite into PTFE has light effect on the impact and tensile strength of composites. The tribological properties of the composites were investigated on M-2000 wear tester at dry friction condition. The wear mechanism was also discussed and the wear surfaces were examined by SEM. The result indicates that fibers which diffused in PTFE matrix wind with PTFE molecule chain, and then form grid structure. The load-bearing capacity of composites can be obviously enhanced and the trend of block fragmentations slide is inhibited, so that the tribological properties are improved markedly.
Facile Synthesis of Hierarchical Architecture FePO4/C Composite Microspheres
Authors: Wang Sha Sha , Mu Long Fei , Li Song , Li He , Wen Zhong Sheng , Ji Shi Jun , Sun Jun Cai
Published: September 2013

Carbon coated micro/nanostructure FePO4composite materials were synthesized by hydrothermal methode, in which citric acid was used as both complexant and carbon resource. The dependence of synthesis process and complexant on the structure and morphology of composite materials were investigated by X ray diffraction (XRD) and scanning electronmicroscopy (SEM). The results showed that the sample consisted of dispersive microspheres with a quite uniform size distribution of 10μm through hydrothermal reaction at 130°C for 24h, when solution concetration was 0.03mol/L and pH value was nearly 2. After calcinated at 550°C for 3h, the microspheres were comprised of nanosticks, and their specific surface area can reach nearly 14 m2/g. Due to their micro/nanomicrosphere structure, the composite materials will benefit to the increase of lithium diffusion rate meanwhile preserve high tap density.
Synthesis and Optical Properties of ZnS Nanoparticles Using Multi-Mercaptan-Terminated Thio Ether as Surface Modifier
Authors: Sheng Wei Chen , Tan Jing , Wu Ping , Chen Qiao , Zhou Zhi Ping
Published: September 2013

ZnS nanoparticles have been prepared by using 2, 3-dimercaptoethylthiopropanethiol (BES) as the coordinating modifier reagent to form Zn-thiol complex at low reaction temperatures. By controlling the experimental conditions, the diameter of the ZnS nanopaticles can be tuned from 43 nm to 115 nm. Systematic experiments were carried out to investigate the factors such as the amounts of the reagents (thiourea and BES) and the temperature, which have great influence on the sizes of the products. And when the content of BES is much higher, ZnS nanopaticles with mercapto surface modification were synthesized. In addition, massive blue shift in UV-vis spectra has been observed and the photoluminescence spectra of the ZnS show a strong emission at approximate 432 nm and 527 nm. Therefore, the preparation and properties studies of different ZnS sizes will offer great opportunities to explore the dependence of a material’s properties and find many interesting applications in the optical devices.
Study on the Adsorption Performance of Zn(II) over Bentonite
Authors: Pan Guo Xiang , Zhang Ya Jing , Chai Da Gan , Yu Yan Fei
Published: September 2013

Bentonite is applied in the simulative waste water containing Zn (II) ions in this paper, and the influences of initial pH value, temperature, adsorption time, Zn (II) concentration on the adsorption performance have been tested, and thermodynamic and kinetic equation are fitted. The results show that Zn (II) adsorption capacity increases firstly and then tends to balance as the pH increases. The higher the temperature is, the better adsorption capacity is. Zn (II) adsorption occurs within 60 minutes. Langmuir equation is used to fit adsorption thermodynamic equation, which indicates that the adsorption can occur spontaneously, and it is an endothermic and entropy increasing process. In addition, a kinetic equation is more suitable for the description of Zn (II) adsorption mechanism, and adsorption activation energy calculated is 6.90 kJ/mol.
Biocompatibility of Degradable Stents Constructed Different Biomaterials
Authors: Ma Chun Hua
Published: September 2013

Placement for the treatment of coronary atherosclerotic heart disease (CHD) underwent four revolutionary simple balloon dilatation era, bare-metal stent era, drug stent era and completely biodegradable stent era. Completely biodegradable stent is Current research focus. A computer based search of EMbase (1980-01/2011-12), MEDLINE(1966-01/2011-12), CBM(1978-01/2011-08), PubMed (1999-01/2011-12) and CNKI (1999-01/2011-12) was performed. The keywords weredegradable,stents,biocompatibilityin Chinese and English. Indicators including endothelialization degree of coronary artery and incidence of in-stent restenosis were evaluated. 36 articles were included in the final analysis among 262 articles . We systematically evaluated the biocompatibility of vascular stents constructed different biomaterials in these articles and concluded degradable stents may temporarily support vessel wall, smoothly keep blood flow,inhibit thrombosis in an early stage and newborn endomembrane proliferation in later stage and effectively prevent acute vascular occlusion and reduce incidence of restenosis following stent implantation. Biodegradable stents have good biocompatibility and broad application prospects.
The Analysis and Design of Three-Phase Static Inverter Deadband Effect and Harmonic Suppression
Authors: Yan Qun Min
Published: September 2013

in order to solve the problem of three-phase static inverter output waveform distortion, detailed analyzed of the voltage distortion caused by the deadband effect and the resulting harmonic components. The control method is proposed to set the deadband time combining with the voltage compensation, while in order to improve the inverter output, the converter output to design a trap filter and a low pass filter cascaded filtering circuit. Simulated analysis the entire system though Saber, using the digital chip TMS320F2812 to achieve appropriate compensation strategies, simulation results and experimental results have all proved the effectiveness of the design method.
Two Sizes CdSe Quantum Dots Co-Sensitized TiO2-Nano-SiO2 Hybrid Photoelectrodes for Solar Cells Applications
Authors: Wang Ren Bao , Niu Hai Hong , Wan Lei
Published: September 2013

The high-quality two sizes CdSe quantum dots (QDs) with nearly monodisperse size and shape were synthesized by the employed hot injection method with some modifications. The nanoparticles diameters were to be 2.6nm and 3.0nm respectively. To improve crystallization property and specific surface area of TiO2 and to inhibit recombination processes of photoinduced electrons effectively, TiO2-nano-SiO2 hybrid films were prepared by adding proper meso-porous SiO2 into TiO2, in which the mass ratio of SiO2 to TiO2 was 5%. CdSe QDs were linked to TiO2-nano-SiO2 films using 3-mercaptopropionic acid to increase CdSe QDs adsorption. Two sizes CdSe QDs were achieved both to promote charge separation and to ensure the porper mobile pathway of free carriers. The J-V characterization showed that two sizes CdSe QDs co-sensitized TiO2-nano-SiO2 hybrid photoelectrodes had higher short circuit current density (JSC) and open circuit voltage (VOC), compared to one size CdSe QDs.
Analysis of the Flexible Prismatic Pair Processing Errors of a Flexible Parallel Vibration Platform with High Frequency
Authors: Yang Qi Zhi , Yuan Dai Min , Zhuang Jia Qi , Cao Dian Feng
Published: September 2013

In some fields, the rigid prismatic pairs have been gradually replaced by some flexible prismatic pairs. It is described a new type flexible prismatic pair in this paper. Its material is 65Mn spring steel. It is applied to the high frequency vibration field for its elasticity and structural advantages. The prismatic pair is based on a one-way four-bar linkage, which is consisted of some bent plate structures. Firstly its model is designed. Secondly the width error, the incision arc error and some other errors are analyzed in details. Based on the Paros J stiffness calculation formula and the Smith ST error analysis method, its relative stiffness error model is established. Finally by using finite element method, a simulation of deformation is made in the actual working conditions. And the error model is correct.
Study on Preparation and Properties of Foam Glazed Hollow Bead Thermal Insulation Mortar
Authors: Yu Hai Tao , Tao Wen Hong , Fu Xing Hua , Du Bao Li , Chen Yu Peng
Published: September 2013

This paper is the result of research on preparation and properties of foam glazed thermal insulation mortar by means of orthogonal experiment method, the influence of main preparation process parameters on mortar’s dry density and compressive strength, and the optimum combination was obtained. The micro-structure of foam glazed hollow bead insulation mortar was analyzed by scanning electron microscope (SEM), and the mechanism of glazed hollow bead and foaming agent was preliminarily discussed.
Research on the Melting Temperature of CaO-SiO2-B2O3 Ternary Slag Systems
Authors: Yang Li Li , Wang Hong Ming , Zhu Xiang , Li Gui Rong
Published: September 2013

The melting temperature of CaO-SiO2-B2O3-(boron mud, CaF2) slag system was investigated. The slag melting temperature was measured by using the hemisphere method. The results indicate that B2O3 has a significant fluxing effect on the slag system. When 1%-11% B2O3 was employed as fluxing agent, the melting temperature of the slag changed from 1525°C to 1200°C. When the content of B2O3 is 5% and the range of basicity is 1.5~3.5, the melting temperature of the slag increases with the increase of the basicity. However, when boron mud or CaF2 was added to the slag, the melting temperature of the slags decreased with the increase of addition at a fixed B2O3 content (5%) and a fixed basicity (R=2.5). Furthermore, the melting temperature of the slag system which contains CaF2 is lower than the slag system which contains boron mud.
Manufacture and Analysis of Directional Solidification Organization of CMSX-6 Nickel-Base Superalloy
Authors: Liang Xiang Feng , Zhao Yu Tao , Zuo Zhen Li , Jia Zhi Hong
Published: September 2013

In this paper, we use the High rate solidification to study process parameters and CMSX-6 super-alloy solidification structure. And then, it can provide more basis for the industrial directionally solidified casting of superalloys blades. The results show that: under certain process parameters, it can be obtained parallel columnar crystals directional solidification structure. The organization is composed of the matrix γ phase and the secondary precipitated γ ' phase; under an optical microscope, it can be observed the shrinkage porosity due to the volumes reduction arising solidification.
Effects of Heat Treatment on Microstructure and Properties of AZ91D Magnesium Alloy
Authors: Wu Ming , Long Fang , Geng Hao Ran , Yang Fang
Published: September 2013

The microstructure, hardness and corrosion resistance of AZ91D alloy were investigated under different solution treatments and artificial aging conditions.When ascast AZ91D alloy was heat treated at 415°C by solution treatmentfor 12 h and artificially aged at 200°C, the volume fraction of precipitates increased with the aging time up to 10 h.When ascast AZ91D alloy was treated at 430°C by solution treatment for 12 h and artificially aged at 200°C for 10h, the volume fraction of precipitates reached a peak value.The results of the corrosion test showed that a high corrosion resisting of the second phase precipitates was beneficial to improving the strength and hardness. Solution treatment at 445°C temperature for 12 h destroied the consecutiveness of β-Mg17Al12 phases.
Annealing and Deposition Parameters Influence on the Performance of AlN Thin Films
Authors: Gui Tai Long , Jiang Si Da
Published: September 2013

Using the radio frequency magnetron sputtering that directly bombardment A1N target under different sputtering-power and total pressure to deposit the A1N thin films. The crystal structure, composition, surface and refractive index of the thin films were studied by XRD, SEM, AFM and elliptical polarization instrument. The results show that the surface and refractive of the thin films strongly depends on the sputtering-power and total pressure,the good uniformity and smoothness is found at 225 W, Ar flow ratio 5.0 LAr/sccm, substrate temperature 100°Cand 1.2 Pa. All film thickness are from 60 to 80nm, and the highest N/Al mole ratio reach to 0.83.The crystal structure of the as-deposited thin-films is amorphous，then it transforms from blende structure to wurtzite structure as the rapid thermal annealing(RTA) temperature changes from 600 to 1200°C. The refractive index also increases with the RTA temperature it is increasing significantly from 800 to 1000°C. When the Annealing temperature at 1000°C, we get the best uniformity and smoothness of the surface of the film.
Synthesis and Oxygen Sensing Properties of Ti1-xSnxO2 Solid Solutions Nanoparticles
Authors: Wu Ai Qing , Fang Xin Zuo , Lin Xin Hua , Wang Huan Qin , Wang Ying Xian , Zhang Rui , Gao Li Sheng
Published: September 2013

Rutile Ti1xSnxO2(0.2x<1) solid solutions had been prepared using a sol-hydrothermal method, which combined the conventional sol-gel process with hydrothermal method. Hybrid alkoxides of Ti4+and Sn4+were used as precursors in the sol-gel process and Sn4+served as crystal-inducing agent during the formation of rutile crystal lattice in the hydrothermal process at 200°C. The microstructures and morphologies of nanoparticles were detected with XRD and TEM. Rutile Ti1xSnxO2solid solutions nanoparticles with well-distributed crystallite sizes about 10nm were obtained with Sn4+content above 20mol% without any high temperature calcination. The oxygen sensitivity properties of Ti1xSnxO2solid solutions had also been investigated. It is proved Ti1xSnxO2solid solutions exhibited higher oxygen responses than single TiO2or SnO2. A typical sample of Ti0.5Sn0.5O2presented the best sensitivity is approximately 6 under 400°C.
Development of Changeable Young's Modulus with Good Mechanical Properties in β-Type Ti-Cr-O Alloys
Authors: Liu Hui Hong , Niinomi Mitsuo , Nakai Masaaki , Hieda Junko , Cho Ken
Published: September 2013

A novel β-type titanium alloy with a changeable Youngs modulus, that is, with a low Young's modulus to prevent the stress-shielding effect for patients and a high Young's modulus to suppress springback for surgeons, should be developed in order to satisfy the conflicting requirements of both the patients and surgeons in spinal fixation operations. In this study, the oxygen content in ternary Ti-11Cr-O alloys was optimized in order to achieve a large changeable Young's modulus with good mechanical properties for spinal fixation applications. The increase in Youngs moduli of all the examined alloys by cold rolling is attributed to the deformation-induced ω-phase transformation which is suppressed by oxygen. Among the examined alloys, the Ti-11Cr-0.2O alloy exhibits the largest changeable Youngs modulus and a high tensile strength with an acceptable plasticity under both solution-treated (ST) and cold-rolled (CR) conditions. Therefore, the Ti-11Cr-0.2O alloy, which shows a good balance among a changeable Youngs modulus, high tensile strength and good plasticity, is considered a potential candidate for spinal fixation applications.
Foamed Glass-Ceramics Made from Red-Mud
Authors: Ye Zhong Nan , Wang Yong Wei , Jiang Hao , Li Na , Liu Shi Quan
Published: September 2013

Dried Red mud slurry was ground to small powders. It was then mixed with waste glass and dolomite powders. The mixtures with different amounts of red mud and dolomite were pressed to form green bodies, which were foamed at high temperatures. To achieve a good foaming effect, the content of red mud is 35~45% in the batch and 10wt% of dolomite should be added as the foaming agent. It is found that the best foaming temperature is 1130°C, much higher than the decomposition temperature of the pure dolomite. The best obtained product has an apparent density, bending strength of 0.896g/cm3 and 9.7MPa, respectively. X-ray measurement results indicate that the red mud has reaction with the other raw materials used in the green body. The crystalline phase formed in the sample is augite. The present study provides a simple way to directly foam a mixture containing red mud to form useful glass-ceramics.
Design and Test of Controlled Droplet Sprayer for Facility Agriculture
Authors: Gong Yan , Chen Xiao Bing , Liu Yan , Pei Liang , Zhang Jing Chao
Published: September 2013

This article describes a new and efficient type spraying equipment with core technology of controlled droplet (centrifugal atomization), and describes the overall design of the equipment, technical characteristics and innovation. The test results show that the equipment has the following characteristics: precisely controlled droplet diameter, real-time, precisely adjusted spray flow, three-dimensional space evenly spray, and the operating status could be remotely controlled by automation. It is new type spray equipment for facility agriculture applicable for different crop varieties, crop growth period, control objects, pesticide formulations, as well as operating environment inside the green house.
Effects of Sr and Mn-Doping on the Electrical Properties of CaBi4Ti4O15-Based Ceramics
Authors: Fu Bin , Hou Yang Lu , Li Ting , Fu Xing Hua
Published: September 2013

Lead-free Sr-and Mn-doped Ca1-xSrxBi4Ti4O15, Ca1-yMnyBi4Ti4O15 bismuth layer piezoelectric ceramics have been prepared. The microstructure and electrical properties of the products were studied by XRD, SEM and Broadband LRC digital bridge. The obtained ceramics have Bi-layer perovskite phase. The dopings do not change the crystal phase of CaBi4Ti4O15. However, the doping amounts affect the size of crystal grain and porosity of the final products. The appropriate amounts of dopings for obtaining the highest dielectric constant and the lowest dielectric loss are determined. The prepared ceramics show the largest piezoelectric constant of 5.2~5.3 pC/N with the optimal Sr-and Mn-dopings.
Synthesis and Characterization of NiO Doped SnO2 Nano-Flowers
Authors: Tang Wei Ping
Published: September 2013

In this present work, a new method for preparing NiO doped SnO2 nanoflowers by hydrothermal route is suggested. The composition and microstructure of samples were characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and Fourier transform infrared spectrum (FTIR). Moreover, a possible formation mechanism was discussed.
Hydrothermal Synthesis and Ethanol-Sensing Properties of MoO3 Nanobelts
Authors: Liu Min Na , Chen Qian Qian , Lu Xin , Ge Lian Fang , Yin Li , Zhang Rui , Chen De Liang
Published: September 2013

Uniform MoO3 nanobelts were synthesized through a fast and simple hydrothermal route without any other agents. The hydrothermal reaction was performed at 180 °C for 12 h using a HNO3 aqueous solution as the solvent. The phases and microstructures were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicated that the sample obtained was an orthorhombic MoO3 phase, and had a belt-like morphology with lengths of 510 μm and apparent widths of about 220 nm. The MoO3 nanobelts obtained were used as the sensing materials to fabricate chemical sensors for detection of some volatile organic compounds (VOCs) (including ethanol, methanol, isopropanol, acetone, methanal, and benzene). The gas-sensing results indicated that the sensor of the α-MoO3 nanobelts has enhanced ethanol-sensing performance, e.g., with the highest sensitivity of Sr =144 for 500 ppm ethanol vapor operating at 300 °C.
Thermal Cure and Ceramization Kinetics of Perhydropolysilazane
Authors: Ma Feng Ling , Qi Hui Min , Zhu Ya Ping , Ren Xiao Wen , Wang Fan
Published: September 2013

The kinetics of the thermal cure and ceramization of preceramic prehydropolysilazane (PHPS) was investigated by thermogravimetric analysis (TGA) under nitrogen atmosphere. The results indicated that the gases captured during the thermal cure and ceramization process of PHPS, which had three main weight loss events. The corresponding kinetic parameters including activation energy, pre-exponential factor and empirical order of the thermal cure and ceramization stages were evaluated by using Ozawa and Kissinger metnods, respectively.
Dielectric Studies on Alkali Borate Glasses Mixed with Iron Oxide
Authors: Satyanarayana T. , Srinivasa Rao K. , Naga Lakshmi N.T.V. , Nagarjuna G.
Published: September 2013

Glass system of composition Li2O-Na2O-B2O3: Fe2O3with replacing alkali oxides one by another have been prepared via melt quenching. Further, the samples were characterized by X-ray diffraction. XRD studies have indicated that the prepared samples were amorphous in nature. Dielectric properties (constant ε , loss tan δ, a.c. conductivity σacover a wide range of frequency and temperature) of these glasses have also been explored. The activation energy for ac conduction is estimated to be the lowest for glass F25and the highest for glass F0. Finally the study on dielectric properties indicated that the ac conduction is predominantly ionic in nature in the samples containing high content of Li2O.Keywords:Borate glasses; dielectric properties; alkali effect
Effect of Interfaces on Mechanical Properties of Ceramic/Metal Multilayers
Authors: Kot Marcin , Major Łukasz , Lackner Juergen , Rakowski Wiesław
Published: September 2013

Multilayers of alternate Ti/TiN coatings deposited on X20Cr13 ferritic stainless steel by pulsed laser deposition (PLD) method have been tested using instrumented indentation. The effect of bilayer period and metal/ceramic thickness ratio were studied.
Analysis of Dependence between Stress Change and Resonance Frequency for Self-Excited Acoustical System
Authors: Kwaśniewski Janusz , Dominik Ireneusz , Lalik Krzysztof , Sakeb Abdurahim Alfadel
Published: September 2013

Continuous supervision of mechanical endurance is very important in the time of the advance constructions. The Self-excited Acoustical System (SAS) is a kind of a self-oscillating system, which uses the auto-resonance phenomena for measurement of construction stress changes. The advantage of this solution is the ability to apply it to a wide spectrum of materials from elastoplasts to brittle ones where the conventional techniques cannot be used. The Self-excited Acoustical System is characterized by its great sensitivity in comparison with the traditional techniques. This paper presents the results of the research carried out on a metal bar expanded by variable force. The dependence between the relative elongation of the sample and the transition time of the wave was elaborated. The delay occurring during a wave transition has a direct impact on the value of self-oscillation frequency. The influence of the coupling force between a metal sample and the wave receiver was also analysed.
Dynamic Similarity of Wind Turbine's Tower-Nacelle System and its Scaled Model
Authors: Snamina Jacek , Martynowicz Paweł , Łatas Waldemar
Published: September 2013

A paper presents analysis of dynamic similarity between full-scale wind turbines tower-nacelle system and its laboratory model. As a reference real-world structure, Vensys 82 wind turbine was assumed. Complete and partial similarity criteria were both introduced. Considering laboratory model to be equipped with tuned mass damper horizontally arranged at the top, partial similarity of one pair of points (tower tips) motions will be satisfactory. On the basis of similarity conditions, laboratory model parameters were determined so that data acquired for the model may be referred to real-world structure.
Diagnosis of Supporting Structures of HV Lines Using Magneto-Mechanical Effects
Authors: Iwaniec Marek , Witoś Miroslaw , Roskosz Maciej , Gontarz Szymon
Published: September 2013

This paper concerns the idea of using magneto-mechanical effects in prophylactic activities to reduce the risk of occurrence of an extensive blackout on high voltage (HV) lines. The subject matter of the paper is related to the event from April 8, 2008, which deprived approximately 600,000 recipients from 18 cities of the West Pomeranian voivodeship of power and caused millions in losses for the national economy. In theoretical considerations, the idea of diagnosing the technical state and level of effort of steel power line towers using the metal magnetic memory method (MMM) is presented, with a consideration of the methodology for obtaining a reference signal from the external magnetic field. The capabilities of the MMM method have been illustrated by examples of active and passive experiments. Finally, the authors indicated the need of IT support of MMM data analysis using a 3D model of the predicted distribution of the magnetic field in the vicinity of the tested object.
Unusual Region for Pericardial Malignant Mesothelioma: Cutaneous Manifestation in a Turkish Woman
Authors: Günday Murat , Erinanç Hilal , Geredeli Çağlayan
Published: September 2013

Malignant mesothelioma is a disease that originates from mesenchymal cells. It is related to the occupational or environmental exposure to asbestos. The treatment remains controversial because it is commonly diagnosed at a very late stage, and the prognosis is very poor. In this report, we present a 37-year-old female patient who was admitted with shortness of breath, palpitation and inability to sleep on her back for the previous 10 days. A large pericardial effusion was detected on echocardiography. Pericardiocentesis was performed and the patient's symptoms were alleviated. However, approximately 7 months later, she was readmitted to the clinic with complaints of a mass at the incision site. Pathological examination of the mass yielded a diagnosis of pericardial malignant mesothelioma. Malignant mesothelioma is a rare occurrence, and to our knowledge, there are no reports in the English literature of pericardial malignant mesothelioma local invasion to an incision site.
Lymphoepithelioma-Like Carcinoma of the Skin: Case Report and Approach to Surgical Pathology Sign Out
Authors: Morteza Abedi Syed , Salama Samih , Alowami Salem
Published: September 2013

Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare and poorly differentiated variant of squamous cell carcinoma. The lesion is histologically identical to undifferentiated nasopharyngeal carcinoma (lymphoepithelioma), but with Epstein-Barr virus involvement documented rarely. The first case of LELCS was described in 1988 by Swanson et al. and since there has been less than a total of 60 cases documented. This case review discusses a 87 year old man who presented to his primary care physician with a 2.5 cm solitary ulcerated nodular lesion on his right chest for two weeks. The patient ultimately had the lesion excised and sent for histological examination. The microscopic examination, ancillary studies used and differential diagnosis considered are discussed in detail in the following report. This case review aims to provide insight and approach to a rare cutaneous neoplasm, with the conclusions supporting a theory that LELCS is a separate entity from lymphoepithelioma.
Multiple Liver Abscess Formation and Primary Gastrointestinal Stromal Tumor
Authors: Chang Amy E. , Mann Gary N. , Hoch Benjamin , Loggers Elizabeth T. , Pollack Seth M. , Kolokythas Orpheus , Jones Robin L.
Published: September 2013

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract. The introduction of a number of small molecule tyrosine kinase inhibitors has revolutionized the management of metastatic disease. Surgery is the mainstay of management for localized disease. Patients with high risk tumors are treated with adjuvant imatinib. We report the rare presentation of a localized primary small bowel gastrointestinal stromal tumor in association with multiple liver abscesses. Cystic liver lesions should be fully evaluated in gastro intestinal tumor patients to exclude an infective cause. Treatment with intravenous antibiotics resulted in clinical and radiological improvement of the liver abscesses. The small bowel tumor was treated with surgical resection.
Kynurenic Acid in the Digestive System–-New Facts, New Challenges
Authors: Turski Michal P. , Turska Monika , Paluszkiewicz Piotr , Parada-Turska Jolanta , Oxenkrug Gregory F.
Published: September 2013

This review provides information on the most recent findings concerning presence, origin, and role of kynurenic acid (KYNA), a tryptophan metabolite, in the digestive system. KYNA is an antagonist of both the ionotropic glutamate receptors and the alpha7 nicotinic acetylcholine receptor, as well as an agonist of G-protein coupled GPR35 receptor. Since the GPR35 receptor is mainly present in the gastrointestinal tract, researchers have concentrated on the digestive system in recent years. They have found that KYNA content increases gradually and significantly along the gastrointestinal tract. Interestingly, the concentration of KYNA in the lumen is much higher than in the wall of intestine. It has been documented that KYNA may have a positive influence on the number of pathologies in the gastrointestinal tract, in particular ulcers, colon obstruction, or colitis. Future studies might determine whether it is advisable to supplement KYNA to a human organism.
Candidate genes and biological pathways associated with carcass quality traits in beef cattle
Authors: Karisa B. K. , Thomson J. , Wang Z. , Bruce H. L. , Plastow G. S. , Moore S. S.
Published: September 2013

Karisa, B. K., Thomson, J., Wang, Z., Bruce, H. L., Plastow, G. S. and Moore, S. S. 2013. Candidate genes and biological pathways associated with carcass quality traits in beef cattle. Can. J. Anim. Sci. 93: 295–306. The objective of this study was to use the candidate gene approach to identify the genes associated with carcass quality traits in beef cattle steers at the University of Alberta Ranch at Kinsella, Canada. This approach involved identifying positional candidate genes and prioritizing them according to their functions into functional candidate genes before performing statistical association analysis. The positional candidate genes and single nucleotide polymorphisms (SNP) were identified from previously reported quantitative trait loci for component traits including body weight, average daily gain, metabolic weight, feed efficiency and energy balance. Positional candidate genes were then prioritized into functional candidate genes according to the associated gene ontology terms and their functions. A total of 116 genes were considered functional candidate genes and 117 functional SNPs were genotyped and used for multiple marker association analysis using ASReml®. Seven SNPs were significantly associated with various carcass quality traits (P≤0.005). The significant genes were associated with biological processes such as fat, glucose, protein and steroid metabolism, growth, energy utilization and DNA transcription and translation as inferred from the protein knowledgebase (UniprotKB). Gene network analysis indicated significant involvement of biological processes related to fat and steroid metabolism and regulation of transcription and translation of DNA.
Factoring Quality Laboratory Diagnosis into the Malaria Control Agenda for Sub-Saharan Africa
Authors: Aidoo Michael
Published: September 2013

Recent progress in malaria control in sub-Saharan Africa has been achieved primarily through provision of insecticide-treated nets, indoor residual spraying, and antimalarial drugs. Although these interventions are important, proper case identification and accurate measurement of their impact depend on quality diagnostic testing. Current availability of diagnostic testing for malaria in sub-Saharan Africa is inadequate to support disease management, prevention programs, and surveillance needs. Challenges faced include a dearth of skilled workforce, inadequate health systems infrastructure, and lack of political will. A coordinated approach to providing pre-service clinical and laboratory training together with systems that support a scale-up of laboratory services could provide means not only for effective malaria case management but also, management of non-malaria febrile illnesses, disease surveillance, and accurate control program evaluation. A synthesis of the challenges faced in ensuring quality malaria testing and how to include this information in the malaria control and elimination agenda are presented.
Leptospira Species in Floodwater during the 2011 Floods in the Bangkok Metropolitan Region, Thailand
Authors: Thaipadungpanit Janjira , Wuthiekanun Vanaporn , Chantratita Narisara , Yimsamran Surapon , Amornchai Premjit , Boonsilp Siriphan , Maneeboonyang Wanchai , Tharnpoophasiam Prapin , Saiprom Natnaree , Mahakunkijcharoen Yuvadee , Day Nicholas P. J. , Singhasivanon Pratap , Peacock Sharon J. , Limmathurotsakul Direk
Published: September 2013

Floodwater samples (N = 110) collected during the 2011 Bangkok floods were tested for Leptospira using culture and polymerase chain reaction (PCR); 65 samples were PCR-positive for putatively non-pathogenic Leptospira species, 1 sample contained a putatively pathogenic Leptospira, and 6 samples contained Leptospira clustering phylogenetically with the intermediate group. The low prevalence of pathogenic and intermediate Leptospira in floodwater was consistent with the low number of human leptospirosis cases reported to the Bureau of Epidemiology in Thailand. This study provides baseline information on environmental Leptospira in Bangkok together with a set of laboratory tests that could be readily deployed in the event of future flooding.
Efficacy and Duration of Immunity after Yellow Fever Vaccination: Systematic Review on the Need for a Booster Every 10 Years
Authors: Gotuzzo Eduardo , Yactayo Sergio , Córdova Erika
Published: September 2013

Current regulations stipulate a yellow fever (YF) booster every 10 years. We conducted a systematic review of the protective efficacy and duration of immunity of YF vaccine in residents of disease-endemic areas and in travelers to assess the need for a booster in these two settings and in selected populations (human immunodeficiency virus–infected persons, infants, children, pregnant women, and severely malnourished persons). Thirty-six studies and 22 reports were included. We identified 12 studies of immunogenicity, 8 of duration of immunity, 8 of vaccine response in infants and children, 7 of human-immunodeficiency virus–infected persons, 2 of pregnant women, and 1 of severely malnourished children. Based on currently available data, a single dose of YF vaccine is highly immunogenic and confers sustained life-long protective immunity against YF. Therefore, a booster dose of YF vaccine is not needed. Special considerations for selected populations are detailed.
Molecular Confirmation of Co-Infection by Pathogenic Leptospira spp. and Orientia tsutsugamushi in Patients with Acute Febrile Illness in Thailand
Authors: Sonthayanon Piengchan , Chierakul Wirongrong , Wuthiekanun Vanaporn , Limmathurotsakul Direk , Amornchai Premjit , Smythe Lee D. , Day Nicholas P. , Peacock Sharon J.
Published: September 2013

Leptospirosis and scrub typhus are major causes of acute febrile illness in rural Asia, where co-infection is reported to occur based on serologic evidence. We re-examined whether co-infection occurs by using a molecular approach. A duplex real-time polymerase chain reaction was developed that targeted a specific 16S ribosomal RNA gene of pathogenic Leptospira spp. and Orientia tsutsugamushi. Of 82 patients with an acute febrile illness who had dual infection on the basis of serologic tests, 5 (6%) had polymerase chain reaction results positive for both pathogens. We conclude that dual infection occurs, but that serologic tests may overestimate the frequency of co-infections.
Retrospective Derivation and Validation of a Search Algorithm to Identify Emergent Endotracheal Intubations in the Intensive Care Unit
Authors: Velagapudi V.M. , Onigkeit J.A. , Pickering B.W. , Herasevich V. , Kashyap R. , Smischney N.J.
Published: September 2013

Background: The development and validation of automated electronic medical record (EMR) search strategies are important in identifying emergent endotracheal intubations in the intensive care unit (ICU).

Objective: To develop and validate an automated search algorithm (strategy) for emergent endotracheal intubation in the critically ill patient.

Methods: The EMR search algorithm was created through sequential steps with keywords applied to an institutional EMR database. The search strategy was derived retrospectively through a secondary analysis of a 450-patient subset from the 2,684 patients admitted to either a medical or surgical ICU from January 1, 2010, through December 31, 2011. This search algorithm was validated against an additional 450 randomly selected patients. Sensitivity, specificity, and negative and positive predictive values of the automated search algorithm were compared with a manual medical record review (the reference standard) for data extraction of emergent endotracheal intubations. Results: In the derivation subset, the automated electronic note search strategy achieved a sensitivity of 74% (95% CI, 69%-79%) and a specificity of 98% (95% CI, 92%-100%). With refinements in the search algorithm, sensitivity increased to 95% (95% CI, 91%-97%) and specificity decreased to 96% (95% CI, 92%-98%) in this subset. After validation of the algorithm through a separate patient subset, the final reported sensitivity and specificity were 95% (95% CI, 86%-99%) and 100% (95% CI, 98%-100%).

Conclusions: Use of electronic search algorithms allows for correct extraction of emergent endotracheal intubations in the ICU, with high degrees of sensitivity and specificity. Such search algorithms are a reliable alternative to manual chart review for identification of emergent endotracheal intubations.