bluuebunny/crossref_metadata_2025 huggingface dataset:
STIPA Method in Public Adress Sound Systems and Voice Alarm Systems Part 2: Conversion Curves and Bandwidth Effect
Authors: Drtina René , Lokvenc Jaroslav , Šedivý Josef , Čákora Lukáš , Konvalina Jan , Vrba Lukáš
Published: December 2014

Classrooms, lecture, lecture, conference and convention halls can be considered as spaces in which there is sometimes one way, but more often two-way communication through the transmission channel. Equally important is the transfer of key information in voice alarm system.
Synthesis and Characterization of Au/Fe3O4 Nanocomposite
Authors: Yang Xiu Pei , Tan Zhi Jing , Fu Yu Li , Li Gu , Xu Hua
Published: December 2014

A new kind of surface-functionalized magnetic nanoparticles was fabricated by surface modification of ferroferric oxide with monolayer-protected gold nanoparticles. Ferroferric oxide nanoparticles were firstly synthesized by co-precipitating Fe2+ and Fe3+ ions in base solution, and then coated with a layer of 3-aminopropyltriethoxysilane by silanization reaction. Gold nanoparticles were surface-attached with 2-mercapto-4-methyl-5-thiazoleacetic acid which were subsequently linked to the modified ferroferric oxide nanoparticles to produce Au/Fe3O4 composite materials. The outer layer of ligand (2-mercapto-4-methyl-5-thiazoleacetic acid) on Au/Fe3O4 can function as binding sites for drugs and biomolecules, whereas the innermost magnetic cores are able to respond to an externally applied magnetic field. The as-synthesized Au/Fe3O4 nanocomposite is superparamagnetic (31.4 emu/g), thus rendering it potentially applicable in magnetic drug delivery and bioseparation.
Optimization of SDC Interlayer for YSZ-Based IT-SOFCs
Authors: He Shou Cheng , Chen Han , Guo Lu Cun
Published: December 2014

Inserting a porous samaria-doped ceria (SDC) interlayer between yttria-stabilized zirconia (YSZ) electrolyte and anode is an effective method to enhancing the performance of intermediate-temperature solid oxide fuel cells (IT-SOFCs). In this work, the microstructure and morphology of the SDC interlayer were optimized by varying its thickness and sintering temperature. Results show that the SDC interlayer fabricated by utilizing once screen printing method and then sintered at 1300 °C for 2 h obtains the best electrochemical performance. The resulting polarization resistance and anodic overpotential (at a current density of 0.05 Acm-2) were 0.84 Ωcm2and 0.07 V at 800 °C in H2, reduced by factors of 4.7 and 5.6, respectively, when compared with the LSCM anode without the SDC interlayer.
Graded Transitions Homogeneity for Ti-50.8%Ni Processed by ECAP
Authors: Osman Mohamed , Zhang Dian Tao , Tong Yun Xiang , Zheng Yu Feng , Li Li
Published: December 2014

Ti-50.8%Ni shape memory alloy was subjected to four passes equal channel angular pressing (ECAP) with angle 120◦ via route Bc at 450°C. The deformation homogeneity was analyzed on planes across the thickness of the deformed sample by Deform-3D software. Two methods were used from the simulation model to quantify deformation homogeneity , including strain standard deviation (SSD) and inhomogeneity index (Ci). In addition, The deformation heterogeneity of ECAP was analyzed experimentally from microhardness inhomogeneity index ( HII) based on Vickers microhardness test results.In the present work, Ci and SSD had been testified to detect which one could give better results experimentally. It was demonstrated that the simulation results of SSD measurements were in good agreement with experimental results .
A Multi-Objective Fuzzy-Based Procedure for Reactive Power-Based Preventive Emergency Strategy
Authors: El Sehiemy Ragab A. , Abou El Ela Adel A. , Shaheen Abdelallah
Published: December 2014

This paper proposes a multi-objective fuzzy linear programming (MFLP) procedure for maximizing the effects of preventive reactive power control actions to overcome any emergency condition when they occurred. The proposed procedure is very significant and seeks to eliminate violation constraints and give an optimal reactive power reserve for multi-operating conditions. The proposed multi-objective functions are: minimizing the real transmission losses, maximizing the reactive power reserve at certain generator and maximizing the reactive power reserve at all generation systems and/or switchable devices. The proposed MFLP is applied to 5-bus test system and the West Delta region system as a part of the Egyptian Unified network. The numerical results show that the proposed MFLP technique achieves a minimum real power loss with maximal reactive reserve for power systems for different operating conditions.
Effect of Hydrogen on Formation of Fe-Al Nanoparticles by Mechanical Milling
Authors: Lukáč František , Čížek Jakub , Jirásková Yvonna , Procházka Ivan , Vlček Marian , Svec Peter , Janičkovič Dušan
Published: December 2014

Nanocrystalline powders of iron aluminum alloy of the Fe82Al18 nominal composition were prepared under air, hydrogen and nitrogen atmospheres from the Fe and Al elemental powders by mechanical alloying and also from the conventionally cast Fe82Al18 alloy by the high-energy ball milling. The intensive plastic deformation during high-energy mechanical treatment has introduced high concentrations of open volume defects and contributed to a rapid decrease in the crystallite size down to a nanoscopic range.The hydrogen atmosphere was found to be the most efficient for the Fe-Al mechanical alloying since it has resulted into the fully alloyed Fe82Al18 after 30 h of milling. On the other hand, the nitrogen and air atmosphere have slightly prevented mechanical alloying and after the same milling time the pure iron particles were still detected in the powder mixtures. This partial suppression of the mechanical alloying process is explained by a formation of thin iron nitride and/or oxide layers on the surface of Fe particles preventing mutual inter-diffusion of Fe and Al atoms.
Irradiation of Pseudoboehmite-Polypropilene Nanocomposites
Authors: de Miranda Leila Figueiredo , Minhoz Antonio H. , Vicente Rodrigo A. , Terence Mauro C. , Silva Leonardo G.A.
Published: December 2014

Polymeric nanocomposites are hybrid materials, where inorganic nanoscale dimensions substances are dispersed in a polymeric matrix. The fillers have a high surface area, promoting better dispersion in the polymeric matrix and therefore an improvement in physical properties of the composite depending on the homogeneity of the material. The preparation of nanocomposites polymer matrix allows in many cases to find a relationship between low cost due to the use of a lower amount of charge, and a high level of performance. In the present work, nanocomposites of polypropylene with different concentrations of pseudoboehmite obtained by a sol-gel process, and treated with octadecylamine were prepared. After preparation, the samples were irradiated with a 0, 50, 100, 200 e 300kGy radiation dose in an electron accelerator. The pseudoboehmite nanoparticles were characterized by X-ray diffraction, scanning electron microscopy, differential thermal analysis and thermogravimetric analysis. The nanocomposites were characterized by thermal and mechanical tests. The addition of pseudoboehmite promoted a reduction of the melting flow during the production of the composites evidencing the interaction of pseudoboehmite with the polymeric matrix. Because the polypropylene is a semicrystalline polymer, when exposed to the irradiation process, their morphology was modified due to scission mechanisms of the polymer chains.
Grain Size Influence on Microwave Absorption Properties in Nanocrystalline Fe40Co60
Authors: Otmane Fadhéla , Triaa Salim , Bergheul Said , Azzaz Mohammed
Published: December 2014

The work we have undertaken consists of preparing nanocrystalline Fe40Co60 powders by the Mechanical Alloying (MA) route. Characterization of obtained powders was applied on two steps. First, structural properties were investigated. X-ray Diffraction (XRD) was used to identify the formation of a disordered α (Fe40Co60) solid solution with a bcc lattice after 60h milling. By the Halder-Wagner approach lattice size, average grain size and residual strain were fixed. The morphology of milled powders was investigated by Scanning Electron Microscopy (SEM). Then bulk specimens were prepared by cold compaction for microwave measurements. Microwave dielectric permittivity and conductivity were determined using cavity perturbation technique. Microwave absorbing characteristic was measured according to line transmission method. Results obtained confirm that the developed structure after milling is the main factor that influences the microwave properties of nanocrystalline Fe40Co60 powders compared to elemental Fe.
Fe3O4@TiO2 Nanocomposites for Magnetic Targeting Sonodynamic Therapy of Cancer
Authors: Shen Song , Ding Bei , Wu Lin , Qi Xue Yong , Ge Yan Ru
Published: December 2014

Uniform Fe3O4@TiO2 nanocomposites were successfully synthesized via a sol-gel method and then characterized by transmission electron microscope (TEM) and X-ray diffraction (XRD). The obtained composites were monodispersed spherical nanoparticles with average diameter of ~ 230 nm. In vitro cytotoxicity experiment, Fe3O4@TiO2 nanocomposites exhibited good biocompatibility and obvious sonodynamic therapy (SDT) effect. Over 50% cells were killed when the cells were treated with Fe3O4@TiO2 and ultrasound for 1 min. The results indicated the potential of Fe3O4@TiO2 for targeted sonodynamic therapy of tumor.
Synthesis and Characterization of Ultrafine CeO2 Nanoparticles with Photocatalytic Antibacterial Property
Authors: Xue Xue Bin , Wu Shi Long , Xu Xiu Quan , Xu Jing Bo , Li Ye Ping , Huang Li Ying
Published: December 2014

Ultrafine CeO2 nanoparticles were prepared through a calcination method. The photocatalyst was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The performance of photocatalytic antibacterial was investigated by inactivation of E.coli. and S.aureus.
Pharmacology Research Progress of Phenolic Alkaloids from Menisphermum dauricum
Authors: Guo Qi , Jiang Qi , Wang Zhi Guo
Published: December 2014

Phenolic alkaloids from Menisphermum dauricum (PAMD) was a compound of multiple fat soluble alkaloid extracted from Rhizoma Menispermi. PAMD had wide pharmacological effects including of anti-arrhythmia, anti-MI, anti-thrombosis, anti-dementia, anti-cancer, anti-inflammatory, inhibiting respiratory depression, influencing on heart electrophysiology, ptotecting heart and nerve after cerebral ischemia, suppressing pain, lowering blood pressure, improving learning disorder and so on.
Microstructure and Mechanical Properties of Welded Joints of Cr18Ni30Mo2Al3Nb Alloy
Authors: Luo Rui , Cheng Xiao Nong , Xu Gui Fang , Li Dong Sheng , Guo Shun , Zheng Qi , Wang Cheng , Zhang Nan
Published: December 2014

In this present study, A comparative research on the mechanical properties of the dissimilar welded joints of 800H and Cr18Ni30Mo2Al3Nb was investigated. Butt joints were made using argon tungsten-arc welding (TIG). The TIG joint was made using well established welding parameters (i.e., current ampere of 110~120A, welding rate of 105~115mm/min, argon flow 8~10L/min and voltage of 12V). Mechanical behavior of joints was evaluated by room temperature and high temperature (650°C) tensile testing, and hardness testing, respectively. The microstructure of joint was characterized via optical microscopy, and the morphology of tensile fracture was observed by scaning electron microscopy. As can be seen from the experimental results, clearly shown that Cr18Ni30Mo2Al3Nb has better mechanical performance of welded joint than 800H.
The Metastable Micro-Nanocrystals and Formation Mechanism of Rapidly Solidified Al-21Si Multi-Alloys
Authors: Wang Ai Qin , Han Hui Hui , Xie Jing Pei , Li Ji Wen
Published: December 2014

In the present work, rapidly solidified Al-21Si-0.8Mg-1.5Cu-0.5Mn alloys strips was prepared by melt-spinning technique. The microstructure morphology and phase structures of experimental alloy were characterized by means of scanning electron microscopy (SEM), transmission electric microscopy (TEM) and XRD technique. The results show that the grains were refined and the micro-nanocomposite structural were formed under rapid solidification. The nucleation and growth of primary silicon were suppressed and primary silicon could not deposited, meanwhile, α-Al phase was nucleated which prior to eutectic. The microstructure of the Al-21Si alloy was composed of micro-nanostructured α-Al phase and feather-needles-like eutectic α-Al+β-Si phase. The hypereutectic Al-21Si alloy showed the hypoeutectic microstructure. The rapidly solidified Al-21Si alloy microstructure formation mechanism has also been discussed.
Chiral Resolution of Ofloxacin Using Carboxylated Multi-Walled Carbon Nanotubes Mediated Thin-Layer Chromatography
Authors: Huang Du Shu , Long Yun Hui , Hong Yong , Wang Jing , Wu Na , Wu Jie
Published: December 2014

To resolute chiral ofloxacin, we demonstrated a new method of using carboxylated multi-walled carbon nanotubes (MWCNTs) impregnated thin-lay chromatography (TLC). The relative RF value of carboxylated MWCNTs impregnated TLC was 31.3. A general discussion that focuses on the possibility of functionalized MWCNTs in the field of chromatographic chiral resolution is presented.
Lawson Cypress Leaf-Like ZnO Hierarchical Nanostructures by Self-Assembly
Authors: Zou Xiao Ping , Zhao Chuan , Lv Xue Ming
Published: December 2014

In this letter, Lawson cypress leaf-like ZnO hierarchical nanostructures with new and interesting morphology were synthesized by electrodeposition in aqueous solution of Zn (NO3)2followed by annealing process, this structure was the first time appearing in ZnO nanostructure. The obtained Lawson cypress leaf-like ZnO hierarchical nanostructures were composed of ZnO nanoparticles with the grain size about 100~200 nm, were observed by scanning electron microscope (SEM), ZnO was detected by X-ray diffraction (XRD), and the highly crystalline structure was demonstrated by high-resolution transmission electron microscopy (HRTEM). Lawson cypress leaf-like ZnO hierarchical nanostructures, which are well-controlled in diameter, space and thickness, have potential applications in photoelectronic devices, sensors, solar cells and nanometer devices.
Synthesis and Properties of Nano-TiO2 Modified Fluorine-Containing Polyacrylate Soap-Free Emulsion
Authors: Zhou Jian Hua , Wang Lin Ben , Cui Yan Jiao , Ma Jian Zhong , Sun Gen Xing
Published: December 2014

Nano-TiO2Modified Fluorine-Containing Polyacrylate Soap-Free Emulsion was Successfully Synthesized via Soap-Free Emulsion Polymerization Technique, in which the Polymerization Monomers Consisted of Methyl Methacrylate (MMA), Butyl Acrylate (BA) and Dodecafluoroheptyl Methacrylate (DFMA). the Influence of Amount of Initiator, Emulsifier, Containing Fluorine Monomer and nano-TiO2on the Performance of Emulsion was Investigated. the Results Showed that the Good Polymerization Stability, and High Monomer Conversion were Obtained when the Amount of Ammonium Initiator was 1.2%, the Amount of Reactive Emulsifier was 3.5%. with Increasing Amount of DFMA, the Monomer Conversion Decreased and the Gel Rate Increased Gradually with the Increase of DFMA Amount. UV-Blocking Ability of the Cotton Fabric Treated with the Hybrid Emulsion Containing Nano-Tio2increased with Increasing Amount of Nano-TiO2. IR Spectrum Results Showed that Nano-TiO2and Fluorine-Containing Monomer were Successfully Introduced in the Segmental Structure of the Polymer. SEM Revealed that Nano-TiO2was Loaded on the Surface of the Treated Cotton Fabric which had Good Hydrophobicity.
Preparation of Dry Waters and their Fire Extinguishing Performance
Authors: He Yong Jun , Mu Guo Dong
Published: December 2014

Dry waters with ammonium biphosphate solution as core were prepared and used as fire extinguishing agent for the first time. The dry waters were near-spherical and had a size smaller than 200 μm. The fire suppression performance of the dry waters was higher than that of ABC powder. The dry waters with different core composition could be mixed and used as fire extinguishing agent.
Effect of Tetramethyl Ammonium Hydroxide on Dispersion of the Silicon Carbide Submicron Powders
Authors: Wang Nan , Deng Li Rong , Wang Xiao Gang , Lu Shu He
Published: December 2014

The distributed processing of β-SiC submicron powders were carried out by tetramethyl ammonium hydroxide (TMAH). The effects of dispersant on the dispersion stability of the β-SiC powders were investigated by the particle size, flow characteristics, morphology and other physical properties of the powder before and after dispersed treatment. The results show that the best dispersing state of SiC is obtained by using the ultrasonic 7mins. In these conditions, the suspension solid content of β-SiC is 8%, and the dosage of TMAH is 8wt.%. An optimum amount of TMAH is proved as 8wt.% when the solid content is kept as 8wt.%. The powder particle size has been reduced from 0.73μm to 0.45μm, and its flowability has improved significantly after low temperature drying. The dispersed powder has small particle size, uniform distribution and excellent dispersion stability.
Research on Process of Drawing Flexible Glass
Authors: Cheng Jin Shu , Shu Xiang Ping , Lou Xian Chun , Wang Jin , Zhi Guang Lin , Li Min
Published: December 2014

This paper focus on choosing the optimum forming temperature, drawing speed and installing the appropriate apparatus to control the thickness and shrinkage in the process of drawing flexible glass. The results showed that when the temperature of the glass was raised from 990K to 1100K, the thickness of the glass increased at a fixed drawing speed. As the drawing speed of the glass was increased from 6m/h to 21m/h, the thickness of the glass decreased while the shrinkage of the glass increased at a fixed drawing temperature. The optimum forming temperature ranged from 1025 to 1050K and the optimum drawing speed was 21m/h.At the same time, in order to get a suitable size of flexible glass, the pull-edge machines and cooling devices were installed in the drawing apparatus to control the shrinkage of glass.
Experimental Study on the Segregation of Primary Silicon from the Hypereutectic Al-Si Melts in the Electromagnetic Directional Solidification
Authors: Xue Hai Yang , Lv Guo Qiang , Ma Wen Hui , Yang Xi , Chen Dao Tong , Li Shao Yuan
Published: December 2014

Solar grade silicon and modified Al-Si alloys are widely used in the world. These two favored materials are expected to obtain by the electromagnetic directional solidification of hypereutectic Al-Si melts. The segregation of hypereutectic Al-Si alloy is feasible with respect to the process of either pull-up or drop-down in electromagnetic directional solidification. To explore the segregation efficiency, experiments have been conducted in a high-frequency induction furnace with different pulling conditions of hypereutectic Al-Si melts. The results show that the segregation efficiency of dropping-down is higher than that of pulling-up; the slower dropping-down rate lead to higher segregation efficiency in the electromagnetic directional solidification; increasing the temperature gradient may promote the separation efficiency. A separation mechanism model responsible for the formation of the distribution of primary silicon in the cross-sections is also proposed. Wish to provide theoretical basis for the more efficiency of the segregation of hypereutectic Al-Si melts.
Corrosion and Protection of 0Cr18Ni9 Stainless Steel Cooling Water Pipe in Power Plant
Authors: Yan Ai Jun , Hu Wei Juan , Cao Ying , Cao Mo , Yang Zhi Qiang , Feng La Jun
Published: December 2014

This paper analyzed the morphology and reasons of pitting corrosion perforation of 0Cr18Ni9 stainless steel cooling water pipes in a power plant and pointed out the measures to prevent the pitting corrosion under this condition. The results showed that: the reason of pitting corrosion of 0Cr18Ni9 stainless steel cooling water pipes was the existence of multiple Cl-and easily fouling Ca2+ and Mg2+ in water, with the corrosion products mainly the oxides of Fe and Cr; the economic measures to prevent pitting corrosion were to increase the pH of water and decrease the content of Ca2+ and Mg2+.
Acoustic Emission Response of 316LN Welded Joint during Intergranular Corrosion
Authors: Chai Meng Yu , Duan Quan , Zhang Zao Xiao
Published: December 2014

The acoustic emission (AE) response of 316LN welded joint during intergranular corrosion (IGC) was investigated in this study. The boiling nitric acid method was chosen to provide the IGC environment and AE signals were detected by Macro-SAMOS AE testing system. The metallographic structures and AE results were studied and analyzed in detail. The results show that the IGC process of 316LN welded joint can generate many AE signals and the AE activity is high. The AE amplitude is below 35dB and mainly ranges from 25dB to 34dB. Two types of AE signals are obtained and both the frequency peaks are 50 kHz. It is believed that grain boundary corrosion, ferrite corrosion and separation of grains are the possible AE sources.
First-Principle Studies of a High Entropy Solid Solution of AlCoCrCuFeNix with Different Mole Fractions of Ni
Authors: Wang Lan Xin , Yao Shan , Wen Bin
Published: December 2014

The structural properties, elastic properties, and heat of formation of a high entropy alloy (HEA) of AlCoCrCuFeNi containing different mole fraction of Ni. The calculated results indicate that the lattice parameter decreased and the mass density increased as the mole fraction of Ni increased. The high entropy solid solutions AlCoCrCuFeNixusing the FCC model are mechanically stable. The elastic properties have been deduced by Voigt-Reuss-Hill (VRH) approximations, and the calculated ratio of shear modulus to bulk modulus indicated that When the mole fraction of Ni was 0 in the FCC model, or 0.5 in both the BCC and FCC models, the high entropy solid solutions were considered ductile materials. All the HEAs are thermodynamically stable due to their negative heats of formation.
Preparation and Research of α-Fe/Montmorillonite Magnetic Material
Authors: Shi Cheng Cheng , Peng Long Gui , Wang Zhi
Published: December 2014

α-Fe/montmorillonite (MMT) magnetic material was successfully prepared by the in-situ pillared-reduction method. The composite material was characterized by X-ray diffraction (XRD), laser particle size analyzer and other instruments. The magnetic property was researched by saturation magnetization. The results showed that: when 0.1mol/L hydroxyl-Fe was added as pillared agent, hydroxyl-Fe and cation of the MMT exchanged, leading to the inter-layer spacing expanded to 1.41nm and reached saturated pillared point. MMT interlayer hydroxyl-Fe was completely restored to α-Fe grains of 116nm when reducing agent was 0.2mol/L and produced α-Fe/MMT composite material. The average particle size of the composite was 5.529μm, the specific saturation magnetization was 0.812emu/g (9×103A/moutside magnetic field) and exhibited ferromagnetism.
Study on the Microstructure and Biocompatibility of Inositol Hexakisphosphate-Modified Titanium Surface
Authors: Xiao Dong Qin , Tan Zhen , Zhang Cheng Dong , Guo Tai Lin , Duan Ke , Weng Jie
Published: December 2014

The surface topography and biocompatibility of titanium mesh treated with inositol hexakisphosphate (IP6) was studied. At high concentration of IP6, micro-grooved titanium surface with width of ~ 8 μm was formed. Then, calcium phosphate coating was deposited on the micro-grooves by a second hydrothermal treatment. Furthermore, cell culture results showed that micro-grooved surface could guide cell elongation and stretching along the grooves. Calcium phosphate modified micro-grooved titanium surface enhanced the cell viability compared with the unmodified surface. Therefore, IP6 modification may be a good candidate for improving the biocompatibility of titanium implants.
Preparation and Properties of Triazine Dithiol-Silane Composite Self-Assembled Hydrophobility Films on Stainless Steel Surfaces
Authors: Hu Ming Ming , Zhang Dong Ming
Published: December 2014

Self-assembled method for controllable fabrication of a hydrophobic triazine dithiol-silane composite film on 304 stainless steel (SS) is reported in this paper. Hierarchical structure composed of micro/nanofeatherlike surface was obtained by acid etching. After modification with 2-( Dibutylamino )-4,6-dimercapto-1,3,5-triazine ( DB ) and n-octadecyltrichlorosilane ( OTS ), the suface became hydrophobicity. By applying SEM, FTIR-RAS, and water contact angle analysis, the surface morphology and hydrophobicity of the as-prepared surfaces were studied in detailed. The results indicated that at the optimal condition, the surface showed a good hydrophobicity with a water contact angle as high as 152±3°. Possible growth mechanism of featherlike hierarchical structure was discussed. Additionally, the anticorrosion effect of the hydrophobic surface was studied by potentiodynamic polarization measurement. It showed that the surface covered with hydrophobic composite film was found to be more positive than bare and monolayer, the corrosion current was significantly lower to 1.68 nA/cm2, and the corrosion potential shifted positively from-253 mV to-118 mV ( vs SEC ).
Effects of NaBH4 and Heat-Treat on Corrosion Resistance of Electroless Plating Ni-B Coating
Authors: Dong Chu Xu , Sun Wan Chang , Zhang Ju Mei , Cai Hui , Niu Li Bin
Published: December 2014

Ni-B/Ni-B-B4C composite coatings on the substrate of medium-carbon steel (45#) were successfully fabricated by electroless plating in a low temperature bath. The corrosion resistance of Ni-B coating were examined by using electrochemical workstation. The results indicated that there are no pores and cracks and other defects at the interface between the substrate and composite coating. It was found that the corrosion resistance of Ni-B coating increased and then decreased with the addition of NaBH4 increasing, and the best addition in plating bath was about 0.9 g/L. While the corrosion resistance of Ni-B coating heat-treated at 400°C with NaBH4 addition 0.9 g/L was the worst.
Preparation and Properties of Electroless Ni-P-β-SiC Composition Coating
Authors: Zhang Xiao Meng , Niu Li Bin , Wei Xiao Cui , Wang Xiao Gang , Hua Xiao Hu
Published: December 2014

Through orthogonal test of Ni-P chemical plating process optimization to determine the optimum process recipe, the Ni-P-β-SiC composite coating were prepared by chemical plating method. The deposition rate, microhardness, composition and organization of Ni-P-β-SiC composite coating are observed and analyzed by scanning electron microscopy (SEM), vivtorinox microhardness tester, X ray diffraction (XRD) and energy spectrum analysis (EDS). The influences of β-SiC particle concentration in bath on the solution of composite coating deposition rate and microhardness. The results show that the influence of composite coating deposition rate and microhardness are NiSO4•6H2O, NaH2PO2•H2O, C3H6O3, and PH. The optimum process conditions: NiSO4•6H2O 25 g/L, NaH2PO2•H2O 27 g/L, C3H6O327 ml/L, PH 5.2. It was found that the Ni-P-β-SiC composite coating with 5g/Lβ-SiC particles exhibited a maximum deposition rate and microhardness, the deposition rate of composite coating is 12.32μm/h, microhardness is 567.93HV0.05.
Influence of Pulse Frequency on Mullite Coatings Prepared by Pulse Arc Discharge Deposition Process and Activation Energy
Authors: Zhang Bo , Huang Jian Feng , Li Cui Yan , Cao Li Yun , Ouyang Hai Bo , Zhou Lei , Bai Zhe
Published: December 2014

Mullite coatings were prepared on C/C-SiC composites surface by pulse arc discharge deposition using mullite powder as source materials. Phase composites and microstructures of the as-prepared mullite coatings were characterized by XRD and SEM. Deposition kinetics and influence of pulse frequency on the phase composites and microstructures were investigated. The results indicate that the outer layer is composed of mullite phase, density and homogeneity of the mullite coatings are achieved when the pulse frequency reaches 2000 Hz. The deposition amount of the mullite coatings also increases with increasing deposition temperature. The deposition mass of the coatings and the square root of the deposition time at different deposition temperatures according to linear relationship, and the deposition activation energy is calculated to be 32.24 kJ/mol.
Study of Xonotlite Architectural Coatings for Exterior Wall Insulation Mechanism
Authors: Liu Li , Yue Yi , Cao Jian Xin
Published: December 2014

Thermal insulation exterior wall coating has been successfully prepared, using styrene-acrylic emulsion as film former, and xonotlite as heat-insulating filler, which produced by hydrothermal reaction. The insulation mechanism of xonotlite is explored, through analyzing the microstructure of homemade xonotlite thermal insulation exterior wall coating. The results show that xonotlite is a kind of compound type heat-insulating filler that can effectively weakened the heat transfer in the coating, like heat conduction, thermal convection and thermal radiation.
Anti-Corrosion Property of Atomic Layer Deposition Films for Anodized Aluminum
Authors: Jia Yi , Yang Mang , Lu Wei Er , Ji Feng , Li Chao Bo , Fang You Tong , Xia Yang
Published: December 2014

Single and multilayer of Al2O3 and TiO2 were fabricated on anodized aluminum by atomic layer deposition. The effect of processing parameters on pore sealing and anti-corrosion property was studied. It is concluded that the micropores on anodized aluminum could be sealed by atomic layer deposition oxide films through SEM and staining experiments. The anti-corrosive property is affected mainly by the film thickness and process temperature. The acidic drip and salt spray test shows that the anti-corrosion property is enhanced as the film thickness increase. With the similar thickness, Al2O3/TiO2 multilayer film has the best anti-corrosion property, while the single Al2O3 layer appears the poorest. The complementary roles between two basic materials result in the enhanced application property.
Synthesis of Sr4Al14O25:Eu2+, Dy3+ via Using Cyclodextrin as Chelating Agent by Sol-Gel Method
Authors: Xu Wen Feng , Liao Cheng Li , Xiong Fu Hang , Li Kui , Liao Xiao Ling
Published: December 2014

Sr4Al14O25:Eu2+, Dy3+ luminescent phosphor was synthesized for the first time from using cyclodextrin as chelating agent by sol-gel method. The structural characterization, surface morphology and properties of the phosphor were studied. The results revealed that the target phosphor with relatively regular morphology, smaller grain size, pure phase and high crystallinity can be achieved at 1200°C for 4 h in a reducing atmosphere. The average grain size of the Sr4Al14O25:Eu2+, Dy3+ phosphor nanoparticles ranges from 50 to 100 nm . And the phosphorescence in blue-green (483 nm) by Eu2+.
Si/SiO2 Composite Negative Electrode Material for Lithium Ion Batteries
Authors: Liu Min , Zhang Na , Zhao Feng Hui , Zhao Xiao Qin , Chen Ke , Yang Ning , Liu Dun , Chen Yong
Published: December 2014

As lithium-ion battery anode materials, silicon has the highest specific capacity. In order to restrain pure silicon’s serious volume change and enhance its electrochemical performance, Si/SiO2 composites were prepared by using a convenient high energy ball-milling technique. The characteristics of the composites as anode material for rechargeable lithium-ion batteries were investigated by X-ray diffraction and scanning electron microscopy methods. The electrochemical performance of the anode material was studied, and it was found the composite anode had a high capacity of 1333 mAhg-1 in the first cycle and 400 mAhg-1 could still be obtained after 46 cycles. Such prepared materials displayed improved cycle life.
Photocatalytic Activity of Solar-Light-Active N-Doped TiO2 by Sol-Gel Combustion Method
Authors: Du Xian , Du Hui Ling , Shi Xiang , Wang Jin , He Jiao Jiao
Published: December 2014

The present work was dedicated to the tailored synthesis of TiO2nanopowders doped with nitrogen (called TiO2−xNx) for the photocatalytic degradation of methyl orange. In particular, the systems were synthesized by a sol-gel combustion route starting from nitric acid and tetrabutyl titanate (Ti (OC4H9)4) as raw materials. The powders were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), suggesting that anatase phase is obtained at pH value of 4-6 and the heat-treated temperatures as low as 425°C. The photocatalytic activities of the N-doped TiO2nanopowders were monitored from the results of the degradation rate of methyl orange (MO) under solar light irradiation. The dependence of dye degradation rate on photocatalyst amount and initial pH was investigated. Under solar light irradiation, the TiO2doped with 30% N exhibited the highest photocatalytic reactivity, which could be attributed to the structure of the combustion-synthesized catalyst and the change of the bandgap induced by nitrogen inclusion.
Preparation of TiO2 Photocatalyst Loaded Bentonite Material and Study of Catalytic Degradation
Authors: Wang Ce , Peng Long Gui , Zhang Qiao Qiao , Qiu Lu Ying , Zhang Zai Yong
Published: December 2014

A intercalated TiO2photocatalyst loaded bentonite was prepared by sol-gel method. The effect of reaction time, reaction temperature,the amount of butyl titanate and other process parameters on prepared material of degradation of methyl orange,as well as the relationship between the concentration of methyl orange on degradation process and illumination time were discussed by single factor method.The results showed : the first absorbance of the intercalated TiO2photocatalyst loaded bentonite material was 0.342 and the average absorbance was respectively 0.7402 through 5 washing after the intercalated TiO2photocatalyst loaded bentonite irradiated at UV-irradiation 1.5h to 20mg/L methyl orange.
Effect of Humidity on Selective Surface of Solar Absorber Plates
Authors: Zemanová Matilda , Krivdová Patricia , Híveš Ján
Published: December 2014

Selective layers Al2O3-Ni were prepared by electrochemical way applying anodic oxidation of aluminium and electrolytical colouring. Anodic oxidation of aluminium was realised in sulphuric resp. phosphoric acid and colouring was carried out under periodic reverse current using different colouring electrolytes on nickel basis. The selective layers were studied and analysed with diverse methods before and after exposition to humidity effect. A way of the selective layer preparation is decisive to the final reaction with humidity and so to degradation of the material.
Corrosion Degradation of Steel Pipes in Indirect Cooling Circuit of Gas Cleaning
Authors: Hagarová Mária , Cervová Jana , Vojtko Marek
Published: December 2014

The paper deals with corrosion damage to steel pipes which were a part of the indirect cooling circuit of gas cleaning. The pipes were made from steel ASTM A106 Gr.B. The outer surface of pipes of the inside part of the circuit was affected by flue gases with mean temperature of approximately 1200 °C. The pipes of the outside part of the circuit were exposed to outer environment with mean temperature of about 25 °C. The cooling water flowing in these pipes had mean temperature of about 20 °C and contained a corrosion inhibitor based on zinc chloride (with addition of hydrochloric acid, phosphoric acid and PBTC). Flow rate of cooling water was 3700 m3/h, its total volume 1500 m3, and the pressure of cooling water was 600 kPa. The achieved thickening of cooling water was N=4. Side filtering was accomplished by a filter DPF 4000. The pipes of the cooling circuit were welded to each other, which initiated stress stimulating development of cracks on the outer surface of pipes in the heat-affected zone, Fig.1. The existing technological conditions resulted in formation of deposits on the outer pipe surfaces. Their presence changed thermal conditions in steel pipes.
Atmosphere Aggressivity State Mapping in Slovak Republic for Corrosion of Construction Materials
Authors: Kozák Ján , Ivašková Martina , Koteš Peter
Published: December 2014

The paper is focused on the effect of multi-pollution of atmosphere on the construction degradation in the Slovak Republic. Corrosion increases the risk of failure, which has considerable impact on maintenance costs. The objective of the article is a creation of the proposal that should be used for processing of the corrosion maps for the various construction materials. It uses dose-response function that was developed based on long-term research. The corrosion map does not help to protect materials; however it can be useful for prediction of risks by design and analysis. The research done by the other researchers is taken into account also in our work. The results would be used as a basis for the beginning of a long-term research work.
Influence of Temperature on the Electrochemical Characteristics of Ti-6Al-4V
Authors: Ivašková Martina , Lovíšek Martin , Jančovič Peter , Bukovinová Lenka
Published: December 2014

Titanium is not only the most widely used biomaterial for medical implants, but with its very good mechanical properties, corrosion resistance and low density is also applicated in many sectors of industry (aerospace, military, aviation, machinery, energetics, chemicals, etc.). In this paper it is described the influence of temperature on the electrochemical characteristics of Ti-6Al-4V alloy. The surface was mechanically grinded and polished by chemical-mechanical process. Basic electrochemical characteristics were determined by potentiodynamic tests in 0.1M NaCl solution at different temperatures. The obtained results were analysed by the Tafel-extrapolation method. Finally, a modified Arrhenius relation was used for determination of activation energy. The activation energy of grinded and chemical-mechanical polished surface is nearly three times higher than activation energy of only grinded surface.
Chronic kidney disease of unknown etiology: Mystery unsolved
Authors: Mangala P , De Silva CS
Published: December 2014

DOI: http://dx.doi.org/10.4038/jur.v2i1-2.7848J. Univ. Ruhuna 2014 2:1-3
A NEW SPECIES OF DNOPHERULA FROM KENYA (Orthoptera, Acrididae)
Authors: Schmidt G.H
Published: December 2014

A new species of the genus Dnopherula Karsch, 1896 (Gomphocerinae, Acrididae) was collected in Kenya, near Nairobi on grassland under bushes. The fronto-vertical angle of both sexes was much greater than 450 indicating a geophilous behaviour. The tiny insects have short antennae, swollen hind femora, specially in male, and strongly curved spurs on hind tibiae. The fastigium verticis had a parabolic shape, prozona and metazona of pronotum of equal length, median carina straight, lateral carina incurved, pronotal disc constricted, and lateral carina cut by transverse sulculi.
SARDULUS SACERENSIS CASALE & MARCIA, NUOVA SPECIE IPOGEA DI COLEOTTERI ISTERIDI DELLA SARDEGNA NORD-OCCIDENTALE E SUA MORFOLOGIA LARVALE (Coleoptera, Histeridae)
Authors: Casale A. , Marcia P. , Manca I. , Grafitti G.
Published: December 2014

Sardulus sacerensis Casale & Marcia, nuova specie di Histeridae ipogei della Grotta di Lu Gardu (Sassari, Sardegna nord-occidentale) è descritta e comparata con le due specie note in precedenza della Sardegna centro-orientale, S. spelaeus Patrizi, 1955, e S. incrassatus Magrini & Fancello, 2005. Le caratteristiche morfologiche esterne
e i genitali maschili delle tre specie sono raffigurati. Inoltre, è fornita per la prima volta la descrizione della morfologia larvale di una specie di questo genere. S. spelaeus, specie nota fino ad ora di due grotte in territorio di Dorgali, è segnalata di una terza località: la Grotta di Istirzili o Stirzili, nel territorio di Baunei.
SU NUOVI TAXA DI CARABUS E CYCHRUS DELLA CINA (Coleoptera, Carabidae)
Authors: Cavazzuti Pierfranco
Published: December 2014

Si presenta la descrizione di sei nuove sottospecie di Carabus Linnaeus, una nuova specie ed una nuova sottospecie di Cychrus Fabricius, provenienti da diverse regioni della Cina: Carabus (Rhigocarabus) broukpitlik latipes n. ssp., C. (Pseudocranion) lazikouensis laolongensis n. ssp., C. (Pseudocranion) gansuensis honorandus n. ssp., e Cychrus vignai n. sp., del Gansu meridionale; Carabus (Neoplesius) nanshanicus huzhubeianus n. ssp., C. (Calocarabus) mayashanus lingensis n. ssp. e C. (Coptolabrus) formosus picetophylus n. ssp., del Qinghai nord-orientale; infine Cychrus marcilhaci yuhuangianus n. ssp. dell’Henan occidentale.
OSSERVAZIONI SULLA BIOLOGIA DI VESPERUS MACROPTERUS (Coleoptera, Cerambycidae)
Authors: Sechi Daniele
Published: December 2014

Il presente lavoro fornisce un primo contributo alla conoscenza della biologia di Vesperus macropterus Sama, 1999 ed è basato su osservazioni in campo, effettuate in un sito della provincia di Cagliari. Le femmine di questa specie depongono le uova sulle infiorescenze disseccate di alcune piante erbacee anche a più di 1,5 m di altezza; le larve neonate raggiungono il terreno spostandosi sulla superficie o all’interno della pianta, a seconda della specie vegetale dove è avvenuta la deposizione. In nessuna altra specie del genere Vesperus Dejean, 1821 è mai stata osservata una tale biologia. Si ipotizza inoltre che esista una correlazione tra lo sviluppo delle ali membranose delle femmine e l’atipica strategia di ovideposizione della specie.
NOTE SULLA VALIDITÀ SPECIFICA DI TRECHUS NICOLEAE MONCOUTIER, 1986 (Coleoptera, Carabidae)
Authors: Magrini Paolo , Degiovanni Augusto
Published: December 2014

Nella presente nota viene elevato a livello specifico Trechus nicoleae Moncoutier, 1986, considerato in passato come sottospecie di T. liguricus Jeannel, 1921 (Moncoutier 1986, 1990) o di T. putzeysi Pandellé, 1867 (Coulon 2004). Esso risulta ben distinguibile dagli affini T. putzeysi (con il quale convive in parte dell’areale) e T. liguricus, per la diversa morfologia dell’organo copulatore maschile: le differenze di morfologia esterna non vengono considerate un carattere diagnostico costante e affidabile. Viene confermato il nomen invalidum per Trechus [liguricus] nicolianus Moncoutier, 1990, e vengono confermate le sinonimie con le rispettive forme tipiche di T. putzeysi vesulinus Jeannel, 1927 (Vigna Taglianti 1993) e T. liguricus mancinii Jeannel, 1921 (Magrini 1990).
RECENSIONE
Authors: Cassola Fabio
Published: December 2014

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NEW RECORD OF DOLICHOPODA FROM NORTHERN IRAN (Orthoptera, Rhaphidophoridae)
Authors: Di Russo Claudio , Rampini Mauro
Published: December 2014

The record of a new sample of Dolichopoda from Northern Iran is reported. The morphological study of this material allowed the authors to attribute the studied specimens to D. Hyrcana Bey-Bienko, 1969, whose geographic distribution now extends eastwards to the Alborz Mountains in North Iran.
A NEW SPECIES OF TRECHUS FROM THE ETHIOPIAN PLATEAU (Coleoptera, Carabidae)
Authors: Magrini Paolo , Quéinnec Éric , Vigna Taglianti Augusto
Published: December 2014

A new species of Trechus from the Oromia Province (Ethiopia) is described in the present note. This new taxon shows some peculiar characters, such as a much swollen abdomen of pseudophysiogastric aspect, a feature shared by other high altitude Trechinae, as for instance Queinnectrechus Deuve, 1992 from Asia. The integuments are glabrous; the antennae are short; the pronotum is larger than long, with regularly rounded sides and hind angles; the elytrae are short and rounded (pseudophysiogastric) with the first six striae well engraved, on the third of them two discal foveolate setae are well visible. The aedeagus is big and stout, abruptly narrowing at the tip (in lateral view), with a small botton slanting upwards; the copulatory piece is big and well sclerified, triangular, with a more or less sharpened tip. Well recognizable for the “pseudophysiogastric” aspect, Trechus (Trechus) ericalis n.sp. belongs to the bipartitus group.
Biomarkers in the diagnosis and prognostic assessment of acute respiratory distress syndrome
Authors: Yan Jing , Rao Qun
Published: December 2014

Acute respiratory distress syndrome is a common syndrome in clinical practice, particularly in the Intensive Care Unit (ICU), with a high morbidity and mortality rate. The prerequisite of its early treatment is early diagnosis. The early biomarkers hence have been gradually favored. While some new and original biomarkers continue to be the focus of research, some biomarkers such as C-reactive protein and procalcitonin have been widely used in clinical practice.
Left liver lobe diameter albumin ratio as a predictor of esophageal varices in patients with cirrhosis: A preliminary report
Authors: Mudassir Laeeq Syed , Hasan Luck Nasir , Kumar Wadhwa Rajesh , Abbas Zaigham , Mujahid Hasan Syed , Younus Mahira , Mubarak Muhammed
Published: December 2014

Objective: The aim of this study was to determine the significance of the ratio of diameter of left lobe of liver with serum albumin as a non-invasive predictor of esophageal varices. Materials and Methods: All consecutive patients with clinical cirrhosis were included in the study. The study was conducted in the Department of Gastroenterology and Hepatology, Sindh Institute of Urology and Transplantation (SIUT), Karachi, Pakistan. All patients underwent full history taking, clinical examination, relevant laboratory investigations and abdominal ultrasound evaluation. Measurement of the right liver lobe diameter (RLLD) and left liver lobe diameter (LLLD) was performed using ultrasound in the mid-clavicular line and central line, respectively. Esophago-gastroscopy was performed for the detection and grading of esophageal varices. Calculation of the RLLD and LLLD/serum albumin ratio was performed and analyzed for clinical significance. Results: One hundred and eleven subjects (80 males; 72%), with a mean age of 40.09 ± 13.6 years were studied. Esophageal varices were seen in 68 (61.3%) patients and Child-Pugh class A accounted for 41.4%, class B for 45.9% and class C for 12.6% cases. The mean value of RLLD/serum albumin ratio was 5.05 ± 1.90 in patients with varices versus 4.24 ± 1.64 in patients without varices (P = 0.023). The mean value of the LLLD/serum albumin ratio was 2.41 ± 0.90 in patients with varices versus 1.89 ± 0.61 in patients without varices (P < 0.001). Areas under curve were 0.377 and 0.69 for the RLLD/ serum albumin ratio and LLLD/serum albumin ratio, respectively. At a cut-off value of 1.5, the sensitivity was 88.1% and the specificity was 72.1% for the LLLD/albumin ratio. Conclusion: The LLLD/albumin ratio is a better predictor of esophageal varices than the RLLD/albumin ratio in patients with liver cirrhosis.