bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of RFID Technology in Fresh Milk Processing and Packaging Logistics Management
Authors: Sheng Long , Xia Tian
Published: November 2013

Fresh milk in people's diet structure position become more and more important, so a set of fresh milk processing and packaging logistics management system to establish is more and more urgent. RFID tag is the key factor to build the management system, which base on RFID technology realizing non-contacted long distance object recognition as the core. In this article, the principle and features of RFID tag are first introduced. Then material selection and tag reader layout are discussed in detail and designed feasibly. Finally the workflow, logical architecture and implementation strategy of fresh milk processing and packaging logistics management are studied.
Quality Traceability System of Meat Products Based on RFID
Authors: Zhang Han Yue , Chen Xiao
Published: November 2013

This article use the Internet of things technology, supply chain management and the combination of RFID and bar code to establish the traceability system for meat, achieve real-time monitoring and management, aimed at realize the traceability of pork, thus to strengthen the quality management, when quality problem occurs, judge the problem promptly and accurately, ensure food sanitation, promote the healthy development of meat industry.
Research of Food Safety Supervisory System Based on RFID
Authors: Li Meng Xiao , Gu Ping , Ge Jing Huan
Published: November 2013

This paper is aimed at constructing RFID-based food safety supervision system, conducting hardware construction and RFID carrier design, building RFID middleware model, and putting forward RFID information encryption algorithm, to ensure that this system can realize collection, transmission, processing, and security management of food information, achieve scientific and transparent management of food, and improve the food safety supervision mechanism in China.
Study on the Luminescent Property of Fluorescent Inkjet Ink Based on Additive Color Imaging
Authors: Zhang Wan , Wei Xian Fu , Huang Bei Qing , Yang Ling
Published: November 2013

Fluorescent ink can be applied not only in anti-fake packaging products, can also be used on other field to present a special artistic effect. The samples of fluorescent inkjet ink were prepared by changing the type of solvent, the excitation and emission wavelengthexcitation and emission intension were measured,and fluorescent quantum yield were calculated. The result shows Solvent has large effect on the luminescent intensity and fluorescent quantum yield of fluorescent material, and the optimal formula of solvent is Ethyl Acetate: Propylene Glycol Monomethyl Ether: Acetone=0.00:0.50:0.49.
Displacement and Vibration Behavior of Reinforced Concrete Cantilever
Authors: Wu Xin Yan , Lou An Ping
Published: November 2013

In this paper, finite element model (FEM) of a reinforced concrete structure cantilevered slab was established in non-linear finite element software ABAQUS. Influence of cantilever length and tensile reinforcement on the structural displacement and vibration frequency was calculated. The results show that the vibration frequency of the first order and maximum displacement will various with the diameter of the reinforced cantilever slab and the length of the cantilevered slab. This paper will offer the references to the analysis and design of the cantilever slab.
Aluminide Coating Prepared on Ni-Base Superalloy by Pack Cementation
Authors: Zhou Feng , Gao Ming , Tu Gan Feng , Liu Kui , Peng Ke Wu
Published: November 2013

Alumincoating was prepared on a Ni-Cr-W-Al nickel-base superalloy by pack cementation, the effects of Al content and aluminizing temperature on coating formation were investigated. Coating microstructures were investigated using optical and scanning electron microscopes, EDS and X-ray diffraction (XRD) techniques. The results showed that the coatings prepared at 800°C in the powders with 15%, 30% and 99% Al were different. NiAl3 coating was obtained in the conditions of aluminizing temperature of 700°C, 750°C, 850°C and of Al content of 99%.
Orifices Stress Concentration Study by Static and Dynamic Combination Loads
Authors: Liu Dong Qiao , Li De Jian , Yu Xi , Zhang Shen , Guan Lei
Published: November 2013

By the use of the experimental system of Impact Rockburst, which was designed by State Key Laboratory for GeoMechanics and Deep Underground Engineering, the stress concentration for orifices in a cubic gypsum specimen subjected to static and dynamic combination loads was studied. The different triaxial precompression was loaded on gypsum specimen, then the dynamic cyclic loading is exerted in the direction of σ1, while the constant stress is exerted in σ2 and σ3. For the stress strain curve, the data of force and displacement were collected by the servo control system in real time. By the strain gauge near the orifices, the strain was recorded by the dynamic strain collecting device, that result in the orifices stress was obtained. In addition, the phenomenon of inner wall of the orifices was real-time photographed. Based on elastic theory and dynamic stress concentration theory, we calculated the stress near the orifices, which keep pace with the results of test.
SVM Regression Modeling Based on Properties of Engineering Materials with PLS Feature Extraction
Authors: Wu Ya Rong , Li Hua Ping , Gan Xu Sheng
Published: November 2013

A combination regression algorithm of PLS-SVM is proposed for the properties of engineering materials. The algorithm first extracts the feature from the primal sample sets by PLS, and then carries out SVM regression estimation using the new sample sets attained. Thus the algorithm will have the ability of extracting feature. The simulation results indicate that the new combined SVM regression algorithm can effectively solve the regression estimation problem including dimensions reduction, noise elimination and multiple correlations between independent variables. The algorithm has good and wide application foreground in research of properties of engineering materials.
Study on Energy Materials with Analysis of China Green Recycling Family Farms Build Mode
Authors: Lv Dan
Published: November 2013

This paper adopt comparative analysis methods to study the family farms build mode which is emphasize on environmental protection and aimed at recyclable resources. It reported the present situation of the family farm in China, besides, it carried on comparison and analysis on the method that developed countries construct environmentally friendly farm. Conclusion: using biomass waste in agricultural process as new energy materials, applying biomass biochemical convert technology into family farm, realizing clean production, at the same time, the government should support the environmental protection enterprise, and increase investment in agricultural technology service and the agricultural informationization construction. Implement purpose of making full use of material, effective converting energy, having a significant economic and ecological environment benefit.
Comprehensive Analysis and Research on the Factors Influencing Energy Efficiency and Consumption of Public Buildings
Authors: Zhang Yu , Zhang Lei
Published: November 2013

A public building of Jiangsu Province is analyzed by DeST software based on the coupling relationship of building envelope, natural ventilation, lighting and natural lighting, and HVAC system, and the annual heating and cooling loads and power consumption of design building and benchmark building are calculated. After fully taking into account coupling relationship of all factors, a reasonable choice of design parameters, the design of HVAC system is optimized, achieving the goal that total energy consumption of design building is less than 80% of specified value of energy efficiency by national and local standards.
Research on Battery Energy Storage System in Suppressing Power System Oscillation
Authors: Zhang Huai De , Li Bei , Zhang Jian Sheng
Published: November 2013

Based on the advantage of battery energy storage system (BESS), which can work in four quadrants, it is proposed to utilize BESS to suppress low-frequency oscillation. Derive the model with BESS and make the simulation by using the Matlab. Simulation results show energy storage devices can effectively improve the system stability and increase the system damping when they are installed in the appropriate position.
Synthesis of a Biotinylated AKT Inhibitor Analogue
Authors: You Yue Hai , Gong Shan Shan , Sun Qi
Published: November 2013

In chemical biology, analogues of AKTI-IV have potential value. A method for the preparation of these analogues has been developed from simple ingredients.
The Resource Utilization of Color Steel Plate Waste Residue
Authors: Li Ming , Yu Yan Zhen , Guo Yu Zhong , Wang Juan Ting
Published: November 2013

Preparation of water purifying agent by color steel plate waste will attain the goals of managing the waste by waste. The influence factors of the dissolution rate of aluminum was explored,and the optimum conditions were obtained: leached in 10% hydrochloric acid solution and heated by 90°C water bath for 3 hours. The effect of coagulant is best at the pH 6 when the dosing quantity is 0.5ml/L.
Impact of After-Treatment Devices on Biodiesel Engine Particle Number Emission Characteristics
Authors: Yao Di , Lou Di Ming , Tan Pi Qiang , Hu Zhi Yuan , Feng Qian
Published: November 2013

Based on a diesel engine fuelled with BD20 biodiesel, particle number (PN) emission characteristics of the engine equipped with DOC, DOC+DPF and none after-treatment device were investigated respectively by engine bench tests. Results showed that both of DOC and DOC+DPF reduced PN emissions, DOC mainly reduced PN in size range of 30nm~50nm smaller diameter, DPF reduced PN of particles larger than 10nm diameter obviously. PN reduction rate of DOC and DOC+DPF were 5%~35% and 60%~98%, DPF contributed 35%~90% of PN reduction rate on the base of DOC. The after-treatment combination of DOC+DPF was recommended as the device with high efficiency in particle number emission control of biodiesel engine.
Experimental Study on Urea Dosing Strategy for SCR on an Engine Fuelled with Bio-Diesel
Authors: Ren Hong Juan , Lou Di Ming , Tan Pi Qiang , Hu Zhi Yuan
Published: November 2013

Urea dosing strategy for SCR is studied for a diesel engine fuelled with bio-diesel BD20. Bio-diesel BD20 is consisted of biofuels made from waste cooking oil and national V diesel, and biofuels accounts for 20% by volume. The results show that, bio-diesel engine torque decreases by a maximum of 0.55%, brake fuel consumption rate increases by a maximum of 0.53% ,when the urea dosing strategy is adjusted and the engine and SCR are not changed. ESC tests show that, the maximum of NOXconversion ratio is 95%, the minimum is 57%, and the average value is 74% under ESC 12 conditions except idling, the maximum of HC decrease ratio is 74%, the minimum is 35%, and the average value is 55%, when the urea is dosed. NOXemission is 1.55 g/(kW·h) in ESC test, NOXemission is 2 g/(kW·h) in ETC test, and NH3slip is lower than 10×10-6, which proves that the NOXemission from the engine fuelled with BD20 can meet national emission standards V by adjusting the urea dosing strategy.
Effect of Different Mineralizers on Luminescence Characteristic of ZnO Crystals by Hydrothermal Method
Authors: Zheng Wen Li , Yang Wei
Published: November 2013

A comparative study worked on crystal morphology and luminescence characteristic by hydrothermal method with mineralizer of 3 mol /L KOH, fill factor of 35%, under the condition of three kinds of mineralizers which included 3 mol /L KOH in sample 1, 3 mol /L KOH and 1 mol /L LiOH in sample 2, 3 mol /L KOH and CaO: Zn ( OH) 2 = 2% (amount of substance percentage). Nonpolar ZnO crystals were synthesized by adding proper proportion of CaO or LiOH,the speed of growth along c-axic was weakened obviously. The obtained ZnO crystals exposed more areas on the positive polar face c { 0001}. meanwhile,it exposed negative polar-c {000},positive pyramidal face + p { 101},negative pyramidal face-p {10} and hexagonal faces m {1010}. Only KOH or LiOH auxiliarily added,the emission spectrum was only visible light,no UV light from band edge transition, indicating that the crystal defects luminous center are numerous. A strong UV band emitting from band edge transition was in luminescent spectrumn of the prepared crystals by adding CaO,which indicated a decrease in defects luminous center.
Reaction Paths upon Reduction of bis(2-(benzoylamino)phenyl)disulfide
Authors: Wang Cheng Jun , Liu Guo Dong , Gong Shan Shan , Sun Qi
Published: November 2013

A study on the reaction paths of the reduction of bis (2-(benzoylamino) phenyl) disulfide revealed that both intramolecular cyclization and intermolecular substitution reactions happened upon cleavage of the disulfide bond by triphenylphosphine under acidic condition.
Simulation of the Phase Diagrams for High-Chromium White Cast Irons and Multi-Component White Cast Irons
Authors: Yen Chien Lung , Liu Kun Lin , Pan Yung Ning
Published: November 2013

In this study, simulation or computation of the phase diagrams for specific alloys of the high-Cr white cast irons and the multi-component white cast irons was performed by employing Thermo Calc software package and appropriate thermodynamics modules. The phase diagrams constructed were verified by thermal analysis (DSC), optical microscopy and X-ray diffraction analysis. Both the obtained phase transition points via DSC and the microstructures observed by optical microscopy and XRD analysis match well with the phase diagrams.
The Application of Rock Pyrolysis Parameters in Predicting Shale Oil Favorable Area
Authors: Xue Hai Tao , Wang Qi , Yan Hai Yang , Zhang Hong Yang
Published: November 2013

Gulong depression is one of the inheritance deposition and subsidence center, also is the most developed secondary structural belt in Songliao Basin. In this research area, the total organic carbon TOC content of the shale in Qingshankou Formation is mainly more than 1%. The organic matter of the shale in Qingshankou Formation has better types, typeIis major and followed by typeII. The maturity of the source rock in Qingshankou Formation of Gulong area is greater than 0.7%, and up to 1.8%, mainly in the mature-high mature stage. Since the shale of Qingshankou Formation has the features of great thickness, higher organic matter abundance, better type and mature-high mature stage, also it is located in the junction between lake facies and delta front facies with better brittle mineral content, so its the key area of the exploration of shale oil. In this text, find the areas which is S1 is more than 2 mg/g and the brittle mineral (quartz and feldspar) content is more than 50% in Gulong depression, and this areas are consistent with the distribution of industrial oil wells and low yield industrial oil wells in research area. This text provides a fast and effective method for the exploration and development of oil shale.
Evaluation of New Active Polymer Systems
Authors: Tang Jia Bin , Wu Wen Xiang , Zhang Zhu Xin
Published: November 2013

Using the physical simulation experiment, for the new active polymers, common carve and polymer 25 million to act on interfacial tension test, the results indicate, interfacial tension for common carve and polymer 25 million is about 10 mn/m. and interfacial tension for the active polymer is about 1 mn/m. Rheology showed that the viscosity and elasticity of active polymer solution were higher than 25 million polymer.In liquidity experiment, active polymer solution has the better liquidity than in 25 million polymers in the low permeable formation,the flooding effect of active polymer is better than 25 million polymer and common carve polymer.the better injection and better oil displacement features of active polymer are suitable for low permeability reservoirs to improve oil displacement effect.
Investigation of Well Patterns of Horizontal-Vertical Wells for the Exploitation of Tight Reservoir
Authors: Zhang Hai Yong , He Shun Li , Gu Dai Hong , Luan Guo Hua , Mo Shao Yuan , Li Guang Ming
Published: November 2013

In general, the scale of production, exploitation period and the economic benefits of oil and gas field are, to a large extent, depended on the selection, deployment and adjustment of well patterns, especially for tight reservoir. So far, some problems exist in Changqing low permeability oil field, such as the effective displacement system is not easy to be established, a low utilization efficiency of injection water, low oil production and so on. Therefore, five kinds of different well pattern schemes are designed. Then, the well pattern schemes are optimized through numerical simulation method based on the exploitation index including the daily oil output per well, moisture content and oil recovery. Results show that the well patterns of horizontal-vertical wells have better development efficiency than the well patterns of vertical wells. For the optimized well pattern, when the horizontal segment length of horizontal well is 300m, the optimalizing well spacing is 400m and the optimalizing row spacing is 100~150m.
Iron-Free Hydroxyapatite Powder from Synthetic Ca(OH)2 and Commercialized Ca(OH)2
Authors: Kien Pham Trung , Minh Do Quang , Thanh Pham Thi Lan
Published: November 2013

The object of this study is to develop an easy and simple technique to fabricate iron-free hydroxyapatite (HA) powder from CaCO3 using precipitation method. Previously, we successful to fabricate HA from Ca(OH)2 and H3PO4, however, the calcining HA at 1000°C expose the green color with [Fe] is around 177ppm. In order to improve the quality of synthetic HA, CaCO3 was used to fabricate Fe-free Ca(OH)2 or Synthetic Ca(OH)2 The resultant study indicates that CaCO3 precursor helps to improve the quality of synthetic HA powder.
Microstructural Study of Sn-3.0Ag0.5Cu Alloy on Cu/NiP-Coated Substrate by Addition of Fe, Sb and Ce
Authors: Anasyida Abu Seman , Nurulakmal Mohd Sharif , Yusoff Mahani , Teh Chia Li
Published: November 2013

In this study, the effects of alloying elements Fe (0.2 wt.%), Sb (0.5 wt.%) and Ce (0.5 wt.%) on the Sn-3.0Ag-0.5Cu lead-free solder system were investigated. The solder alloy was reflowed on electroless Cu/NiP-coated substrates and their behavior such as microstructure, wetting angle and intermetallic compound (IMC) formation were analyzed. The results showed that the presence of Fe, Ce and Sb reduced the grain size of β-Sn as compared to solder without addition of alloying element. The addition of Fe and Ce was the most significantly refined the microstructure of Sn-3.0Ag-0.5Cu solder alloys. Sn3.0Ag0.5Cu0.2Fe0.5Ce solder was revealed better spreading behavior on Cu/NiP coated substrates which have the lowest IMC thickness of 0.558 μm.
Porous Cordierite Synthesized Using Corn Starch
Authors: Hasmaliza Mohamad , Lim Yu Min , Norfadhilah Ibrahim
Published: November 2013

Cordierite (2MgO.2Al2O3.5SiO2) is an advanced ceramic which is popular for its high melting temperature and high resistance to thermal, chemical and corrosion and also low dielectric constant. The use of various structure of cordierite especially porous structure became more popular where its properties can be tailored by controlling the open and closed porosity, cell size distribution and cell morphology. In this study, porous cordierite was synthesized using sol gel method with addition of corn starch (5wt%, 10 wt%, 15 wt% and 20 wt %) as pore forming agent. Characterizations have done using scanning electron microscope (SEM) show that the corn starch used is polyhedral shape with pore size between 6-7 μm. Whereas SEM analysis on sintered sample shows that the porosity obtained ranging from 13 to 46 % with interconnected pores.
Structural and Optical Properties of Fe-Doped ZnO Nanorods
Authors: Abd Aziz Siti Nor Qurratu Aini , Pung Swee Yong , Lockman Zainovia , Hamzah Nur Atiqah
Published: November 2013

Fe-doped zinc oxide nanorods (ZnO NRs) were synthesized byex-situdoping using spray pyrolysis technique. In this work, the undoped ZnO NRs were pre-synthesized via chemical vapor deposition using Zn powder and oxygen gas at 650 °C. The average length and diameter of the ZnO NRs are 4.1 ± 1.1 μm and 553.1 ± 89.6 nm, respectively. The average aspect ratio and areal density of ZnO NRs is 8.2 ± 2.9 and 6.2 ± 1.1 NRs/um2, respectively. Subsequently, these undoped ZnO NRs were kept in the horizontal tube furnace, whereas the dopant solution (FeCl3) of 0.05 M concentration was kept in the aerosol generator, which was located outside of the furnace. The Fe aerosol was flowed into the reactor when substrate temperature reached 650 °C to achieveex-situdoping. At this temperature, some of the Fe atoms were driven into the NRs, forming Fe-doped ZnO NRs particularly at their outer layer. The presence of Fe 2p1/2and Fe 2p3/2peaks at 722.3 eV and 705.7 eV in XPS analysis indicates that Fe atoms were in the local structure of FeO. The Fe-doped ZnO NRs have poor crystal quality attributed to the low IUV/IVisratio in room temperature PL analysis.
The Effect of Pre-Vulcanization Temperature on Mechanical and Rheological Properties of Starch Filled Natural Rubber Latex Compounds
Authors: Yahya Siti Rohana , Hamdan Farah Nadiah , Rashid Azura A. , Azahari Baharin
Published: November 2013

The main objective of this study was to investigate the effect of the pre-vulcanization temperature on mechanical and rheological properties of starch filled natural rubber (NR) latex films. The 10 phr filler loading of starch was added into the latex prior to the pre-vulcanization process at 60°C to 140°C. The dipped films were cured in the oven at 100°C for 20 minutes and cooled at room temperature for 24 hours before stripping. The rheological properties of NR latex compounds were studied based on the viscosity measurement. The tensile and tear tests of starch filled NR latex films were also carried out. The results indicated that the rheological properties of the latex compounds showed shear thickening behavior where viscosity was increased with the increase in shear rate and pre-vulcanization temperature proportionally. The pre-vulcanization temperature at 80°C showed the optimum mechanical properties of starch filled NR latex films.
Comparison of Friction Stir and Tungsten Inert Gas Weldments of AA6061-T6
Authors: Shaari Mohd Rafiza , Hussain Zuhailawati , Almanar Indra Putra , Van Thuong Nguyen
Published: November 2013

In this research, 6061-T6 aluminum alloys were welded using friction stir welding and tungsten inert as techniques in order to investigate the microstructure and mechanical properties. FSW of aluminium alloys has showed better mechanical properties compared to the conventional welding, tungsten inert gas (TIG). FSW weldment did not show any pores at the nugget zone compared to fusion zone in TIG weldment which produced a lot of pores.
Characterization and Gold Assaying Methods in the Assessment of Low Grade Gold Ore from Malaysia
Authors: Baharun Norlia , Ong Pek Ling
Published: November 2013

The low grade gold ore obtained from a local gold mine in Malaysia was characterized using X-ray fluorescence analysis and scanning electron microscope/ energy dispersive X-ray analysis for the deportment of gold. Acid digestion was carried out to determine iron, aluminium, sulphur and arsenic using ICP-OES. Chemical assaying methods viz aqua regia leaching and lead fire assay followed by acid digestion were conducted to determine the head grade of the gold ore. Assessment of gold using fire assay was found reliable to reduce the interferences from the gangue minerals. Despite the lower limit of detection of ICP-OES, there was no appreciable amount of gold detected in the samples leached using aqua regia because of the interference from the gangue minerals and also due to the interlocking of gold with aluminosilicates phase which require high pressure and temperature leaching using hydrofluoric acid to liberate the gold. ICP-OES analysis is reliable depending on the degree of liberation of gold during acid digestion. The head grade for this type of low grade gold ore was found to be in the range of 0.31 g/t to 0.55 g/t where the gold was highly associated with aluminosilicate minerals.
Microstructure of WE43 Magnesium Matrix Composite Reinforced Ceramic Particles
Authors: Rzychoń Tomasz , Dyzia Maciej , Pikos Izabela
Published: November 2013

Magnesium alloys containing yttrium and neodymium are known to have high specific strength, good creep and corrosion resistance up to 523 K. The addition of ceramic particles strengthens the metal matrix composite resulting in better wear and creep resistance while maintaining good machinability. In the present study, WE43 magnesium matrix composite reinforced with SiC and carbon particulates were fabricated by stir casting. The microstructure of the composite was investigated by optical microscopy, quantitative metallography, scanning electron microscope and XRD analysis. Microstructure characterization of WE43 MMC showed inhomogeneous reinforcement distribution and presence of shrinkage porosity. Reinforcing particles are well bonded with the matrix, however, in some cases thin reaction layers was detected. The presence of SiC particles assisted in improving hardness.
Effect of Ti Addition to Zn Filler Metal on Wettability and Reinforcement of Soldered Joint of Aluminum
Authors: Różański Maciej , Adamiec Janusz
Published: November 2013

This article presents the phisicochemical propreties of aluminium brings a lot of difficulties during soldering one of tchem is low melting point. The work also presents results of mechanical and metallographic investigations. Structural examination was performed by means of light microscopy and mechanical properties with the aim of shear strength test. On the basis structural investigation joints made with Zn and Zn with Ti addition indicated possibilities of reinforcement of soldered joint of aluminium
CMT Robotized Welding of Thin-Walled Joints Made of 7xxx Series Aluminium Alloy
Authors: Adamiec Janusz , Rykała Janusz
Published: November 2013

The article presents the course and the results of research on material and technological welding conditions of 7xxx aluminium alloy using low energy welding method (CMT) as well as discusses the properties of welded joints and the application fields of modern low energy welding devices for joining thin aluminium sheets.
Fine Particle Reinforced Composites Obtained by Suspension Method
Authors: Dyzia Maciej
Published: November 2013

In the production of composites by the suspension method (mechanical stirring) may beused, ceramic particles, which are wetted by the liquid metal such SiC, Al2O3or glassy carbon.However, to obtain a stable suspension with the use a particle size below 10 μm is extremelydifficult. Phenomena related i.a. with agglomeration of particles, convection currents over moltenmetal surface make practically impossible to obtain composite material. One possibility to obtainfine reinforced composite is the use of in situ methods, in which the reinforcing phase is formed bythe reaction between the aluminum and the reactive powder oxides such FeO, TiO2, SiO2, NiO, Nb2O5or Fe2O3. Such reactions are exothermic (aluminothermic) and their kinetics dependent onthe dispersion of the reactants, the quantitative phase composition and temperature.The technological solution involving the formation of a suspension with particles (chemically activewith aluminum) is one of the promising solutions to obtain batch material for the synthesis ofcomposites reinforced with Al2O3and intermetallic phases. The aim of this study is to evaluate thesuitability of suspension technology to obtained in situ fine reinforced composite.
The Microstructural Changes after Thermal Shock Applied on Elektron 21 Magnesium Alloy
Authors: Pikos Izabela , Kiełbus Andrzej , Adamiec Janusz
Published: November 2013

The Elektron 21 is a commercial magnesium alloy containing Zn, Nd, Gd and Zr. The addition of rare earth elements improve its mechanical properties at elevated temperatures, what contribute to widen the range of applications. Constructions working at elevated temperatures can be exposed to its rapid changes. The purpose of present paper is to present results of study on reaction of Elektron 21 on applied thermal shock. As-cast material was heat treated according to four different variations. Afterwards, five cycles of thermal shocks, consisted of heating to 200°C (service temperature) and rapid cooling in water, have been applied. After heat treatment and each cycle of thermal shock the hardness and microstructure have been studied. The investigated material revealed satisfactory resistant to thermal shock, regardless of applied various heat treatment.
Potentiodynamic Tests of Magnesium Alloy AZ31 with Lithium Additive
Authors: Przondziono Joanna , Walke Witold , Hadasik Eugeniusz , Lalik Stanisław
Published: November 2013

The purpose of the study is to assess electrochemical corrosion resistance of magnesium alloy AZ31 with additives of 4.5, 7.5 and 15 % lithium in NaCl solutions. Corrosion tests were performed in solutions with concentration 0.01 2 M NaCl with application of electrochemical testing system VoltaLab®PGP201. Resistance to electrochemical corrosion was evaluated on the ground of registered anodic polarisation curves by means of potentiodynamic method. Results of performed tests show unequivocally deterioration of corrosion characteristics of the alloy together with increase of molar concentration of NaCl solution. As chloride ions concentration increases, decrease of corrosion potential and polarisation resistance, as well as increase of corrosion current density are observed. Deterioration of corrosion characteristics of AZ31 alloy was shown with the increase of lithium content. It must be highlighted that irrespective of molar concentration of NaCl solution, there is also presence of pitting corrosion in the tested alloy. It proves that magnesium alloy AZ31-Li is not resistant to that type of corrosion. Test results prove that it is necessary to apply protective films on elements made of magnesium alloy with lithium additive.
Macrophages Are More Potent Immune Suppressors Ex Vivo Than Immature Myeloid-Derived Suppressor Cells Induced by Metastatic Murine Mammary Carcinomas
Authors: Hamilton Melisa J. , Bosiljcic Momir , LePard Nancy E. , Halvorsen Elizabeth C. , Ho Victor W. , Banáth Judit P. , Krystal Gerald , Bennewith Kevin L.
Published: November 2013

Myeloid-derived suppressor cells (MDSCs) are emerging as potential promoters of metastatic tumor growth, and there is interest in targeting immature MDSCs by inducing their differentiation into more mature myeloid cells. We used all-trans retinoic acid (ATRA) to differentiate MDSCs in mice bearing metastatic 4T1 or 4TO7 murine mammary tumors, and assessed the immune-suppressive mechanisms and potencies of different myeloid cell subpopulations. Metastatic mammary tumors induced the accumulation of distinct populations of immature CD11b+Gr1+F4/80−Ly6CmidLy6G+ MDSCs (“Gr1+ cells”) and mature CD11b+Gr1−F4/80+ cells (“F4/80+ cells”) in metastatic target organs. ATRA triggered the differentiation of Gr1+ cells into F4/80+ cells in the lungs and, unexpectedly, enhanced pulmonary metastatic tumor growth. We found that F4/80+Ly6C−Ly6G− mature macrophages (Mϕs) were up to 30-fold more potent immune suppressors than Gr1+ cells on a per-cell basis, which we postulate may contribute to the increased metastatic growth observed with ATRA treatment. F4/80+ cells and Gr1+ cells used different reactive oxygen species (ROS)–mediated mechanisms of immunosuppression ex vivo, with F4/80+ cells producing higher levels of ROS, which is consistent with their superior immunosuppressive abilities. These data highlight the potent immunosuppressive functions of Mϕs, reveal that Mϕs can suppress T cell responses via ROS production, and suggest that ROS inhibitors may be useful in promoting antitumor immune responses. Our findings also caution against using ATRA to modulate myeloid cell differentiation and function to treat breast cancer metastases in the lung, and support the development of therapeutic strategies to enhance antitumor immunity by targeting myeloid cells as a collective group.
Targeting CD137 Enhances Vaccine-Elicited Anti–Respiratory Syncytial Virus CD8+ T Cell Responses in Aged Mice
Authors: Lee Sujin , Mittler Robert S. , Moore Martin L.
Published: November 2013

Respiratory syncytial virus (RSV) causes significant morbidity and mortality in children and the elderly. No vaccines for RSV are in use. Because of immunosenescence, the immunologic requirements for a successful RSV vaccine in the elderly might differ from a RSV vaccine for young children. Using an aged mouse model of RSV pathogenesis, we found that aged mice had impaired Ag-specific CD8+ T cell responses and delayed RSV clearance compared with young mice. To study vaccine-elicited RSV-specific CD8+ T cells in aged mice, we used a peptide vaccine approach. TriVax is a commixture of a peptide representing immunodominant RSV CD8+ T cell epitope M282–90, a TLR agonist (polyinosinic-polycytidylic acid), and a costimulatory anti-CD40 Ab. TriVax vaccination generated robust, polyfunctional, and protective CD8+ T cell responses in young BALB/c mice, but not in 18-mo-old (aged) BALB/c mice. We hypothesized that treatment of aged mice with agonistic anti-CD137 (41BB) mAb will partially restore T cell responses and TriVax efficacy in aged mice. We immunized 18-mo-old BALB/c mice twice with TriVax + anti-41BB mAb or TriVax + isotype control Ab. Coadministration of anti-41BB mAb with TriVax enhanced RSV-specific CD8+ T cell responses and TriVax efficacy in challenge experiments. Triggering the 41BB costimulatory pathway may be a strategy for enhancing T cell responses to vaccines in the elderly.
IL-6–Mediated Induction of Matrix Metalloproteinase-9 Is Modulated by JAK-Dependent IL-10 Expression in Macrophages
Authors: Kothari Poonam , Pestana Roberto , Mesraoua Rim , Elchaki Rim , Khan K. M. Faisal , Dannenberg Andrew J. , Falcone Domenick J.
Published: November 2013

The mechanisms by which IL-6 contributes to the pathogenesis of chronic inflammatory diseases and cancer are not fully understood. We previously reported that cyclooxygenase-2 (Cox-2)–dependent PGE2 synthesis regulates macrophage matrix metalloproteinase (MMP)-9 expression, an endopeptidase that participates in diverse pathologic processes. In these studies, we determined whether IL-6 regulates the Cox-2→PGE2→MMP-9 pathway in murine macrophages. IL-6 coinduced Cox-2 and microsomal PGE synthase-1, and inhibited the expression of 15-hydroxyprostaglandin dehydrogenase, leading to increased levels of PGE2. In addition, IL-6 induced MMP-9 expression, suggesting that the observed proteinase expression was regulated by the synthesis of PGE2. However, inhibition of PGE2 synthesis partially suppressed IL-6–mediated induction of MMP-9. In the canonical model of IL-6–induced signaling, JAK activation triggers STAT and MAPKerk1/2-signaling pathways. Therefore, the ability of structurally diverse JAK inhibitors to block IL-6–induced MMP-9 expression was examined. Inhibition of JAK blocked IL-6–induced phosphorylation of STAT3, but failed to block the phosphorylation of MAPKerk1/2, and unexpectedly enhanced MMP-9 expression. In contrast, MEK-1 inhibition blocked IL-6–induced phosphorylation of MAPKerk1/2 and MMP-9 expression without affecting the phosphorylation of STAT3. Thus, IL-6–induced MMP-9 expression is dependent on the activation of MAPKerk1/2 and is restrained by a JAK-dependent gene product. Using pharmacologic and genetic approaches, we identified JAK-dependent induction of IL-10 as a potent feedback mechanism controlling IL-6–induced MMP-9 expression. Together, these data reveal that IL-6 induces MMP-9 expression in macrophages via Cox-2–dependent and –independent mechanisms, and identifies a potential mechanism linking IL-6 to the pathogenesis of chronic inflammatory diseases and cancer.
Cutting Edge: Expression of FcγRIIB Tempers Memory CD8 T Cell Function In Vivo
Authors: Starbeck-Miller Gabriel R. , Badovinac Vladimir P. , Barber Daniel L. , Harty John T.
Published: November 2013

During reinfection, high-affinity IgG Abs form complexes with both soluble Ag and Ag displayed on the surface of infected cells. These interactions regulate cellular activation of both innate cells and B cells, which express specific combinations of activating FcγRs (FcγRI, FcγRIII, FcγRIV) and/or the inhibitory FcγR (FcγRIIB). Direct proof for functional expression of FcγR by Ag-specific CD8 T cells is lacking. In this article, we show that the majority of memory CD8 T cells generated by bacterial or viral infection express only FcγRIIB, and that FcγRIIB could be detected on previously activated human CD8 T cells. Of note, FcγR stimulation during in vivo Ag challenge not only inhibited the cytotoxicity of memory CD8 T cells against peptide-loaded or virus-infected targets, but FcγRIIB blockade during homologous virus challenge enhanced the secondary CD8 T cell response. Thus, memory CD8 T cells intrinsically express a functional FcγRIIB, permitting Ag–Ab complexes to regulate secondary CD8 T cell responses.
Travel patterns and challenges experienced by University of Johannesburg off-campus students
Authors: Mbara Tatenda C. , Celliers Cynthia
Published: November 2013

When universities across the world emerged, the majority of students were provided with oncampus accommodation. However, with the increase in the number of universities, students seeking to enter universities and the decline in university funding, the result was an increase in the number of students residing off-campus. This lead to more limited social-contact opportunities with other students, which are vital for the enhancement of their learning and development. It also resulted in off-campus students spending a considerable amount of time travelling to and from university. This study aimed to investigate the travel patterns, characteristics and challenges faced by University of Johannesburg off-campus students by ascertaining inter alia: the means of transport used; travel time; the views of students in regard to the challenges they face; and possible improvements thereto. A quantitative approach was predominantly used to collect data from students by means of a questionnaire and this was supplemented with focus group discussions on two campuses. The study results revealed that off-campus students experience considerable challenges accessing campuses.
Diffusion Tensor Imaging of the Kidneys: Influence of b-Value and Number of Encoding Directions on Image Quality and Diffusion Tensor Parameters
Authors: Chuck Natalie C. , Steidle Günther , Blume Iris , Fischer Michael A. , Nanz Daniel , Boss Andreas
Published: November 2013

Objectives:

The purpose of this study was to evaluate to which degree investment of acquisition time in more encoding directions leads to better image quality (IQ) and what influence the number of encoding directions and the choice of b-values have on renal diffusion tensor imaging (DTI) parameters.

Material and Methods:

Eight healthy volunteers (32.3 y ± 5.1 y) consented to an examination in a 1.5T whole-body MR scanner. Coronal DTI data sets of the kidneys were acquired with systematic variation of b-values (50, 150, 300, 500, and 700 s/mm2) and number of diffusion-encoding directions (6, 15, and 32) using a respiratory-triggered echo-planar sequence (TR/TE 1500 ms/67 ms, matrix size 128 × 128). Additionally, two data sets with more than two b-values were acquired (0, 150, and 300 s/mm2 and all six b-values). Parametrical maps were calculated on a pixel-by-pixel basis. Image quality was determined with a reader score.

Results:

Best IQ was visually assessed for images acquired with 15 and 32 encoding directions, whereas images acquired with six directions had significantly lower IQ ratings. Image quality, fractional anisotropy, and mean diffusivity only varied insignificantly for b-values between 300 and 500 s/mm2. In the renal medulla fractional anisotropy (FA) values between 0.43 and 0.46 and mean diffusivity (MD) values between 1.8-2.1 × 10-3 mm2/s were observed. In the renal cortex, the corresponding ranges were 0.24-0.25 (FA) and 2.2-2.8 × 10-3 mm2/s (MD). Including b-values below 300 s/mm2, notably higher MD values were observed, while FA remained constant. Susceptibility artifacts were more prominent in FA maps than in MD maps.

Conclusion:

In DTI of the kidneys at 1.5T, the best compromise between acquisition time and resulting image quality seems the application of 15 encoding directions with b-values between 300 and 500 s/mm2. Including lower b-values allows for assessment of fast diffusing spin components.
Radiological Imaging Findings of a Case with Vertebral Osteoid Osteoma Leading to Brachial Neuralgia
Authors: Gokce Erkan , Ayan Erdoğan , Çelikyay Fatih , Acu Berat
Published: November 2013

Osteoid osteoma is a small, benign osteoblastic tumor consisting of a highly vascularized nidus of connective tissue surrounded by sclerotic bone. Three-quarters of osteoid osteomas are located in the long bones, and only 7-12% in the vertebral column. The classical clinical presentation of spinal osteoid osteoma is that of painful scoliosis. Other clinical features include nerve root irritation and night pain. Osteoid osteoma has characteristic computed tomography (CT) findings. Because magnetic resonance imaging (MRI) findings of the osteoid osteomas causing intense perinidal edema can be confusing, these patients should be evaluated with clinical findings and other imaging techniques. In this study, we present X-ray, CT, and MRI findings of a case with osteoid osteoma located in thoracic 1 vertebra left lamina and transverse process junction leading to brachial neuralgia symptoms.
Computed Tomography Findings of an Unusual Maxillary Sinus Mass: Brown Tumor Due to Tertiary Hyperparathyroidism
Authors: Altay Canan , Erdoğan Nezahat , Eren Erdem , Altay Sedat , Karasu Şebnem , Uluç Engin
Published: November 2013

Brown tumor is a non-neoplastic bone lesion that develops secondary to hyperparathyroidism and it is very rare in the maxillofacial region. We report the case of a 59-year-old man who presented with pain and a swelling in the left cheek. Computed tomography (CT) demonstrated an expansile and radioluscent lesion in the left maxillary sinus. Incisional biopsy was performed, and the diagnosis was Brown tumor. Brown tumor must be considered in the differential diagnosis of expansile lesions of maxillary sinus.
Giant Renal Angiomyolipoma: Unusual Cause of Huge Abdominal Mass
Authors: Taneja Rajesh , Singh Dig Vijay
Published: November 2013

We present the imaging and histopathological characteristics of a giant renal angiomyolipoma (AML) in a 49-year-old female patient, who presented with bloating sensation in the abdomen and a steadily increasing abdominal girth for about 3 years. Contrast enhanced computed tomography (CECT) scan films of abdomen revealed that a large fat containing tumor had replaced the left kidney while displacing the rest of the abdominal contents toward the other side of the midline. Intraoperatively the left kidney was completely replaced by a fat containing tumor. The recovered surgical specimen measured 39 cm × 25 cm × 9 cm and weighed 7500 g. Histopathological investigation with immuno-histochemical staining of the specimen with hydroxy beta-methylbutyric acid-45 confirmed this lesion as AML. CECT scan of the head did not show any lesion suggestive of tuberous sclerosis. The giant tumor of the present case is the heaviest AML in both syndromic and sporadic categories and largest by dimensions as sporadic AML ever reported in the literature.
A Time Splitting Space Spectral Element Method for the Cahn-Hilliard Equation
Authors: Chen Lizhen , Xu Chuanju
Published: November 2013

We propose and analyse a class of fully discrete schemes for the Cahn-Hilliard equation with Neumann boundary conditions. The schemes combine large-time step splitting methods in time and spectral element methods in space. We are particularly interested in analysing a class of methods that split the original Cahn-Hilliard equation into lower order equations. These lower order equations are simpler and less computationally expensive to treat. For the first-order splitting scheme, the stability and convergence properties are investigated based on an energy method. It is proven that both semi-discrete and fully discrete solutions satisfy the energy dissipation and mass conservation properties hidden in the associated continuous problem. A rigorous error estimate, together with numerical confirmation, is provided. Although not yet rigorously proven, higher-order schemes are also constructed and tested by a series of numerical examples. Finally, the proposed schemes are applied to the phase field simulation in a complex domain, and some interesting simulation results are obtained.
Research on the ‘Inside’: The Challenges of Conducting Research with Young Offenders
Authors: James Nalita
Published: November 2013

There is a limited literature examining the ethical dilemmas that arise when research is conducted in prison settings, and the extent to which it is possible to give voice to young offenders’ experiences, thus placing them at the centre of the research process. By drawing on a qualitative research with young offenders, the paper will discuss how prison research can be truly ethical when it is conducted with participants who are far from autonomous. This raises a number of challenges for researchers that this paper will consider. These include accessing young offenders’ lives; ensuring the credibility of young offenders’ voices; and leaving the prison setting. The paper highlights the ethical research strategies that researchers can adopt in conducting research with young offenders, and the importance of researchers adopting a reflexive approach to better understand the social context of young offenders’ lives.