bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of P2O5 on Microstructure and Properties of Calcium Aluminoborosilicate Glasses
Authors: Zhang X.H. , Yue Y.L. , Wu H.T.
Published: March 2013

In alkaline earth aluminoborosilicate glasses containing P2O5, the changes of structure and properties caused by variations in the ratio P2O5/B2O3were investigated. The structure was investigated by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The dielectric constant and tangent loss were measured at 1 MHz. Chemical durability was evaluated by weight losses of glass samples after immersion in water. The results indicated that the fraction of four-coordinated boron atoms (N4), chemical durability and dielectric properties increased with increasing P2O5/B2O3replacements.
Ten-Micrometer-Thick Silicon Diaphragm Used in Condenser Microphone
Authors: Kimori Naoki , Kumai Yuichiro , Hishinuma Shinsuke , Ikehara Tsuyoshi , Maeda Ryutaro , Nishioka Yasushiro
Published: March 2013

Small condenser microphones with high performances are strongly demanded. This paper describes a silicon condenser microphone fabricated on silicon on insulator (SOI) substrate using only one photo mask with improved sensitivity performance. The improvements were due to reduction of the floating capacitance, thinning of the silicon diaphragm, and increasing the electrode area at the back plate of the microphone. This microphone consists of a diaphragm with the thickness of 10 μm and the diameter of 2 mm, a SiO2 insulative spacer (4-μm-thick buried oxide), and a 300-μm thick silicon back plate with the meshed structures having small (60 μm) hexagonal shaped acoustic holes. The gap between the 10-μm-thick silicon diaphragm and the back plate was 4 μm. This microphone was confirmed to function in the auditory frequency region with a sensitivity of –85 ~ -70 dB.
Study on Coherent Dynamics of Alkali Metal Atomic Wave Packets
Authors: Zhu Chang Jun , He Jun Fang
Published: March 2013

A theoretical model consisting of 5 energy levels, with the three upper states coherently excited, was proposed to analyze the coherent characteristics of atomic wave packets using perturbative theory. Pump-probe technique was implemented to detect coupled difference frequency four-wave mixing processes for studying the coherent characteristics of Rb atomic wave packets. Quantum beats were extracted the time domain signal by Fourier transform. Moreover, the variation of quantum beats was gained by time-dependent Fourier transform. The results show that the coherent characteristics of alkali metal atomic wave packets are closely related to quantum beats embedded in the time delayed four-wave mixing signal. Theoretical results are consistent with experimental observations, possessing potential applications in multi-channel information encoding and decoding.
Aspheric Far-Infrared Lenses Based on Hot-Moldable Chalcogenide Glass
Authors: Zhu Yong Jian , Pan Wei Qing , Sun Jian Feng
Published: March 2013

The far infrared lenses are widely used in vehicle and night vision instrument. A new far infrared lens is proposed to enhance their performance of danger recognition at night. It focuses on the infrared light of wavelength from 8µm ~12µm. The lens is based on the uncooled infrared detector with 320x240 pixels. Its main structure is made of one refractive-diffractive aspheric lens and two spherical lenses. To improve the luminous flux, the f-number is set to be less than 1. The field of view (FOV) of 23 degrees is wide enough to help monitor the dangerous signal around the car or community. In addition, in order to reduce the cost and improve the machinability of aspheric diffractive lens, the hot-moldable chalcogenide glass is chosen to be the material of lenses. As a result, the MTF (modulation transfer function) values of lens exceed 0.5 for all field angles at Nyquist frequency. It shows that the lens enjoys high imaging quality.
Bulk-Heterojunction Solar Cells Based on Poly(3-hexylthiophene) and (6,6)-phenyl-C61-butyric-acid Methyl Ester on Polyethylene Terephthalate Substrates
Authors: Yanagi Yuichiro , Okukawa Takanori , Yoshida Akira , Ohzeki Masaya , Yanagidate Tatsuki , Arai Yuki , Kataura Hiromichi , Fujii Shunjiro , Nishioka Yasushiro
Published: March 2013

Bulk-heterojunction solar cells were fabricated based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on an indium tin oxide (ITO) coated flexible polyethylene terephthalate (PET) substrate. Performance improvements of the flexible solar cells by optimizing post thermal annealing conditions are reported. The solar cells annealed at 150 oC showed the minimal deformation of the PET substrate, and the resulted conversion efficiency was 1.35% under the light irradiation conditions of the Superscript textAM1.5 simulated solar intensity of 100 mW/cm2.
Preparation and Application as Biosensor of Water-Soluble Conjugated Polyelectrolyte
Authors: Zhong Yi Ping , Hong Rui Bin , Yin Bin Bin , Liu Ping , Deng Wen Ji
Published: March 2013

The water-soluble conjugated polyelectrolyte, poly[3-(1′-propyloxy-3′-sodium sulfonate) thiophene] (PTH-n3-SO3Na), was prepared. The interaction between the PTH-n3-SO3Na and bovine serum albumin (BSA) was investigated using UV-vis spectroscopy. It was found that the PTH-n3-SO3Na could be used as biosensor to detect BSA.
Anodization Current Density Independent Photoluminescence of Porous Silicon
Authors: Huang Yuan Ming , Zhai Bao Gai , Ma Qing Lan
Published: March 2013

Porous silicon (PS) is usually prepared by means of the anodization under constant current density, and fabrication of PS is a key step towards the realization of all-silicon electronic devices. It is a general belief that the photoluminescent properties of electrochemically etched PS depend on the anodization current density. In this work, we electrochemically prepared a series of PS films in the electrolyte of hydrofluoric acid by varying anodizing current density in the range of 1-70 mA/cm2. In spite of the different anodizing current density, the peak wavelength of the photoluminescence spectrum of the electrochemically anodized PS does not depend on the anodization current density. SEM has been utilized to characterize the morphology of the prepared PS films, and the mechanism is discussed for the anodization current independent photoluminescence of PS.
The Application of Freezing-Melting Hysteresis in Hardened White Cement Paste
Authors: Wang Zhong Ping , Wang Tao , Zhou Long
Published: March 2013

In this paper, the freezing-melting hysteresis was first obtained in two mesoporous molecular sieves with similar pore size to analyze the reason lead to the different results in nuclear magnetic resonance cryoporometry (NMR-C) experiment between them. Then the hardened white cement paste was explored by the same method. The primary results shows that the freezing branch can offer more details to the pore size distribution (PSD) obtained from the melting branch, which will probably improve the accuracy of PSD.
Research on Modification of Steady State Migration Test for Cementitious Materials
Authors: Yang Jin Bo , Zhang Peng , Wu Li Peng
Published: March 2013

Steady state migration test is the main method for determining chloride diffusivity of cementitious materials. In this paper a modified steady state migration test was introduced. The conductivity of anolyte is tested to calculate chloride concentration therefore the time consuming work for determining chloride concentration directly is avoided and the steady state migration test is simplified. A series of concrete mixes with different water cement ratio and different mineral admixtures were tested with the modified steady state migration test. An equation for calculation of chloride concentration using conductivity of anolyte is given. Experimental results show that the modified steady state migration test is effective and convenient. Probable experimental errors caused by determining chloride concentration directly are averted by conductivity determining.
Study on Compatibility of Modified the Cement-Based Composite Biomass Materials by Agent
Authors: Liu Jun , Lin Chao , Sun Wen Hui , Wang Xu Ming
Published: March 2013

Abstract. For the slow process of hydration and complex process of hydration of cement-based composite biomass materials, the paper study the compatibility of straw cement mixed system was evaluated in process of hydration. By testing temperature changes in process of hydration of cement-based composite biomass materials and analyzing the maximum value of hydration temperature, the maximum temperature difference and compatibility coefficient of modified the cement-based composite biomass materials by agent, taken before or after that. It was evaluated that compatibility performance of modified the cement-based composite biomass materials by agent. The results show that the characteristic changes of early hydration heat was reflected with a visual aid by some indexes that are the maximum value of hydration temperature, the maximum temperature difference, and so on. And the early hydration behavior was more comprehensive objective reflected by compatibility coefficient in cement-based composite biomass materials. At the same time, the modified effect of sodium silicate was superior to the polyvinyl acetate (PVAc) in the early hydration of the cement-based composite biomass materials.
The Brief Analysis of Photovoltaic Insulating Glass in the Process Service
Authors: Li Wei Hong , Li Cong , Qiu Yan , Wei Chen Guang
Published: March 2013

This article according to intensity of solar radiation in Beijing region during summer based on this intensity of solar radiation the working temperature of photovoltaic insulating glass were measured. On this basis, the atmospheric pressure which in hollow layer of photovoltaic insulating glass were measured. And the stress of glass is calculated by finite elements software. The results showed that if the glass deflection is less 1 proportion of glass thickness there is a linear relation between stress and deflection. This is a small deflection issue. If the proportion exceeded this limit, the stress exhibited a non-linear relationship with deflection. This is a large deflection issue. The glass stress and deflection ratio which calculated by finite elements is less than the criterion which prescribed by Glass curtain wall project technical specification. The results show that the formula which introduced reduction coefficient used in standard is favors of the security.
Properties of Cement Mortars Mixed with SiO2 and CaCO3 Nanoparticles
Authors: Wang De Zhi , Zhang Yin Yan , Meng Yun Fang
Published: March 2013

Water requirement of normal consistency, setting time and soundness of cement pastes mixed with SiO2 and CaCO3 nanoparticle and the flexural strength and compressive strength of cement mortars mixed with SiO2 and CaCO3 nanoparticles were experimentally studied. Results indicated that the added nano-SiO2 and nano-CaCO3 with a mass account of 4.0 wt. % decreased the setting time and increased the water requirement of normal consistency, flexural strength and compressive strength. And these nanoscaled mineral admixtures did not have a negative impact on cement soundness. The optimal replacement levels of cement by SiO2 and CaCO3 nanoparticles for producing cement mortar with improved strength were 2.0 and 4.0 wt.% respectively.
Investigation of Early Cement Paste with 1H Low-Field NMR
Authors: Sun Zhen Ping , Li Qi , Yu Yang , Yang Pei Qiang
Published: March 2013

Early cement paste (0h-6h) made with cement of different Blain specific surface area was investigated with 23MHz 1H low-field NMR. T2 distribution, T2 against age and T2 distributions against age were obtain. Results showed: 1) T2 distribution of fresh cement paste made with cement of common Blain specific surface area has two peaks and corresponded to water within flocculation and among flocculation; 2)T2 against age could reflect a stage-like behaviour of cement hydration; 3) T2 distributions against age showed evolution of microstructure in early cement paste.
Relative Humidity of Blended Cement Pastes in Sealed during Hydration
Authors: Jin Dan , Yao Wu , Chen Yi
Published: March 2013

As an important part of cement-based materials，water plays an important role during hydration and self-desiccation so the measurement of relative humidity or internal moisture in the research of cement-based materials is vital. In this paper, the measurement samples are blended cement pastes in sealed with different water to cement ratios and different kind of mineral admixtures. The measurement was taken at different ages during hydration to investigate the changes of relative humidity. The result showed that the water to cement ratio was the key factor of affecting the change of relative humidity, and the effect of mineral admixture kind was not very obvious in this experiment.
Effect of Hollow Glass Microsphere on Performance of Foam Concrete
Authors: Wang Qing , Qiu Lin Ge , Yao Qi , Ding Zhao Yang , Yan Xi Fan
Published: March 2013

Dry density and compression strength of foam concrete are conflicting, there is a negative relationship between them. Hollow glass microsphere is a new lightweight material which is lightweight, high strength, low thermal conductivity and good thermal stability. In order to prepare lightweight and high-strength foam concrete, this paper researched the effects of different dosage on dry density and compressive strength of foam concrete through adding hollow glass microspheres. The results show that the thermal conductivity of foam concrete increased as the hollow glass microsphere increases, and the dry densities of foam concrete are between 120-200 kg•m-3, compressive strength reaches 0.1MPa.
Temperature Sensitive Properties of Hybrid Carbon Nanotube/Carbon Fiber Cement-Based Materials
Authors: Qin Jun Jie , Yao Wu , Zuo Jun Qing
Published: March 2013

This paper gives an assessment on the temperature sensitive properties of hybrid carbon nanotube/carbon fiber cement-based materials. Different dosage of carbon nanotube (CNT) were added into a carbon fiber (CF) cement system to produce carbon nanotube-carbon fiber cement nanocomposites in the form of pastes. The temperature sensitivity coefficient, activation energy during heating and cooling, repeatability, linearity and electrical resistivity are tested. Results show that a high dosage of CNTs into cement paste can increase the temperature sensitivity coefficient, activation energy, repeatability and linearity, which has a vast potential for future development of temperature monitoring in concrete structures.
Research on Optimizing the Electrical and Mechanical Properties of Carbon Fiber Reinforced Cement
Authors: Xu Jing , Yao Wu
Published: March 2013

Using orthogonal experimental design, the influence of water-to-cement ratio, silica fume content, and fiber surface treatment on the electrical and mechanical properties of carbon fiber reinforced cement was studied. Moreover, the surface appearance of fibers with and without surface treatment was investigated by means of scanning electron microscopy. The results show that the effect of water-to-cement ratio on conductivity is the largest among all the three factors. Fiber surface treatment plays an important role in the mechanical properties of CFRC and the optimum way is HNO3 treatment. By adopting the method of efficiency coefficient, the best combination can be determined effectively.
Significant Failure Mode Identification for a CFST Arch Bridge System
Authors: Gao Xin , Wang Lei , Zhang Tong
Published: March 2013

The structural reliability analysis is the widely accepted method for bridge safety assessment. Identification the subset of significant failure modes is the most important part of system reliability estimation. In this paper, a stage critical strength branch and bound algorithm is proposed for the failure mode identification of bridge systems. The innovative method is implemented in the combination with the finite element package ANSYS and the MATLAB procedure. The suggest method is applied to a concrete filled steel tubular (CFST) arch bridges. The results reveal various combinations of the failure modes in significantly reduced time and efforts in comparison to the previous permutation method. Additionally, the suggested method can be used for the verification of the system reliability with more specific predictions of the failure mode.
Study on Vehicle-Bridge Coupling Vibration of Equal Span Girder Bridge of Different Span Number
Authors: Li Wei Zhao , Wang Zong Lin , Sun Hang , Li Yan
Published: March 2013

The vehicle-bridge coupling vibration of girder bridge has been widely investigated. But most of previous work focused on the influencing factor of the vibration, such as traveling speed of vehicle, deck surface roughness and vehicle-bridge frequency ratio etc. Taking the box girder bridges of different span number with 20m single span length for example, applying the separated iterative method to multi-sample analysis the vehicle-bridge coupling vibration. The study considered the influence of the vehicle, traveling speed and the random deck surface roughness and then took the average value of the sample to discuss the influence of the span number on the dynamic responses. Results show that the continuous girder form can effectively decrease the dynamic responses of the equal span girder bridge than the simple-supported form. But the influence of the span number on the responses of equal span continuous girder bridge is not obvious.
Modified Formula of Estimating Fundamental Frequency of Girder Bridge with Variable Cross-Section
Authors: Gao Qing Fei , Wang Zong Lin , Guo Bin Qiang
Published: March 2013

Based on present research, there is a big difference between the estimation of the fundamental frequency of Girder Bridge obtained by the design code of bridge, issued by ministry of transport of the P.R. China in 2004, and the theoretical value in some cases. To overcome above issue, theoretical analysis combined with numerical simulation was applied to estimate the fundamental frequency of Girder Bridge with variable cross-section. The effect of the height ratio between mid-span cross-section and support cross-section on the fundamental frequency was discussed in detail. Finally, an improved formula was proposed to estimate the fundamental frequency of Girder Bridge, and the effectiveness of the proposed formula was verified.
The Peak Dynamic Loading of a Winch in Term of the Rope Flexibility
Authors: Michałowski Stanisław , Cichocki Wiesław
Published: March 2013

The cable winch is modeled as a system with two degrees of freedom during a start-up and braking phase for two basic operating cases: raising a lifted load case and elastic bond tensed by a raised load force case. The theoretical calculations were verified with experimental studies. Consequently, it is possible to define the winch drive overloads factor. Moreover, the determination of the number of stress change cycles in the rope can be performed. This important is with regard on possibility of rise in the rope the fatigue cracks. In dynamic experiments, three typical cases of raising mechanisms were taking into account: lifting the load with raising it, lifting the load with tensed rope and braking the load while lowering.
Modern Coating Used in High Pressure Water Hydraulic Components
Authors: Pobędza Janusz , Sobczyk Andrzej
Published: March 2013

Water hydraulics is coming back as an alternative to oil and other not environment friendly working fluids used in very wide range of fluid drive and control systems. One of the barrier causing that water hydraulics is cost of water resistant materials for components, especially moving parts such as pump pistons, surface of cylinder tubes and rods, poppet and seats, etc. to avoid corrosion. One of common solution is to use stainless steel there, where it can cooperate with other nonmetallic material such as plastic or other noncorrosive metallic composite to reduce friction. Thus some of research were directed to elaboration of special coating for covering surfaces in critical regions of water hydraulic components. The article describe results of pilot research on selected components where such coating were introduced on regular carbon steel parts, same as used for oil hydraulics. First part of the article contents description of coating technology and some characteristics of coating layers. Second quotes selected results of conducted by authors research on coated hydraulic cylinders and poppet valves.
The Aluminium and the Steel Supporting System for the Horns Assembly in the High Intensity Neutrino Oscillation Project
Authors: Szybiński Bogdan
Published: March 2013

A new project to analyse neutrino features is under development within the frame of the High Intensity Neutrino Oscillation EURONu project [. The final shape of the magnetic horns supporting system is proposed. This system is designed for four horns joined in one assembly. For the support structure a search for the optimal parameters is made with respect to the static loads. After that dynamic analysis is performed, this is used, if necessary, for the final tuning of the designing parameters. The above approach is investigated for two different materials used for the support system.
Optimal Design of PZT Actuators and Sensors in Composite Structural Elements
Authors: Kędziora Piotr
Published: March 2013

In this paper, the various optimization criteria used for optimal placement of piezoelectric actuators on laminated structures are discussed. Piezoelectric materials are used as layers or fibers that are embedded within or bonded to the surfaces of a structure. The present formulation of optimal design introduces also boundaries of piezoelectric patches as new class of design variables.
Outlook of Preisach Modeling and Magnetic Non Destructive Testing
Authors: Ktena Aphrodite , Hristoforou Evangelos
Published: March 2013

The Preisach formalism is used as a basis for a vector model of magnetic hysteresis in soft magnetic materials subject to tensile stress. The model uses as vector elementary hysteresis operator the Stoner-Wohlfarth mechanism of coherent rotation while the Preisach density is constructed as the weighed sum of probability density functions corresponding to the high and low induction regions. The model reproduces the basic phenomenology of stress-dependent hysteresis: the double peak in differential permeability modeled as the effect of internal demagnetizing fields emerging from residual stresses; the increase in coercivity due to increased pinning; the decrease in magnetic induction as the result of non-180o domain rotation. The role of the negative differential permeability near remanence and its derivative is discussed with respect to residual stresses and magnetic NDT.
Choice of the Best Aspect Ratio in Magnets for Force Improvement
Authors: Íñiguez J. , Raposo V. , García Flores Ana , Zazo M.
Published: March 2013

Magnetic actuators based on rare-earth permanent magnets can be optimized using a suitable amount of material through a correct choice of the aspect ratio and volume. Here, a systematic study is made of the force exhibited by two cylindrical magnets as a function of the aspect ratio, size and distance. The magnetization will be fixed along the axis of the cylinders and the forces are calculated by finite-element simulations, as is usual in axisymmetric problems. Finally a set of experimental results corroborating the numerical calculations is presented.
Realization of Measurement Station for Remote Environmental Monitoring
Authors: Tomić Josif , Živanov Miloš B. , Kušljević Miodrag , Obradović Đorđe , Szatmari József
Published: March 2013

The greenhouse effect is a naturally occurring process that heats the Earth's surface and atmosphere. It is a result of the fact that certain atmospheric gases, such as carbon dioxide, water vapor, and methane, are able to change the energy balance of the planet by absorbing long wave radiation emitted from the Earth's surface. Number of gases are involved in the human caused enhancement of the greenhouse effect. Carbon dioxide is the most important gas of these gases, which contributes about 55% of the change in the intensity of the Earth's greenhouse effect. The global monitoring of the greenhouse gases is necessary for handling the global warming issue. This paper presents a practical implementation of a measurement station for environmental monitoring using Internet technology and large sensor networks. The application of the sensor networks in the environmental monitoring requires the development specific solutions. This paper presents a solution that relies on existing technology, but offers hardware and software upgrade due to the advantages of using the concept of virtual instrumentation. The application uses temperature sensors, air relative humidity sensors, gas sensors and others. The measurement station collects the data from the sensors and sends them to the users using the UDP protocol via the Internet and GPRS modem. The measurement station was implemented in LabVIEW programming package.
Selective Hydrogen Detection in a Highly Contaminated Background Using only a Single Generic Metal Oxide Gas Sensor
Authors: Amini Amir , Babaians Khachik , Gharesi Mohsen
Published: March 2013

Detection of highly ppm range hydrogen concentration in atmospheres contaminated with various volatile organic compounds is in demand for numerous applications. Different devices and techniques have been applied for the problems which are mostly based on utilization of hydrogen permeable membranes. Here, we have used a single generic metal oxide gas sensor for this task. No filter or membrane is utilized. The operating temperature of the sensor is modulated with a voltage waveform specifically designed for producing step-like temperature changes on the oxide pallet. By applying four different step-like temperature jumps, each of 1s duration, the sensor produces response patterns which are processed with common pattern recognition techniques. The technique was examined by its practical use for the ~10 ppm (volume) hydrogen measurement in a background containing ~1000 ppm ethanol. The analysis takes only 4s, and the obtained patterns are reproducible.
Environmental UV-A Level Monitoring Using an Ag-TiO2 Schottky Diode
Authors: Lajvardi Mehdi Mohamadzade , Boroumand Farhad Akbari
Published: March 2013

Here, we demonstrate the field applicability of the Ag-TiO2 Schottky diodes for environmental UV level measurements. The device is visible-blind and it is shown that its maximum sensitivity coincides the environmental UV spectrum (UV-A). These features, along with its low voltage and biasing insensitivity of its operation, simplify the electronic circuit required for the fabrication of a hand-held UV monitoring system.
High Temperature Dielectric, Elastic and Piezoelectric Coefficients of Shear Type Lithium Niobate Crystals
Authors: Mohimi Abbas , Richardson Philip , Catton Phil , Gan Tat Hean , Balachandran Wamadeva , Selcuk Cem
Published: March 2013

In this paper shear type lithium niobate has been studied. The impedance-frequency characteristics were measured at high temperatures. This was carried out by placing the samples inside a furnace and performing in-situ impedance measurements at up to 600°C. The characteristic frequencies, capacitance, density and dimensions of samples were used to calculate the dielectric, elastic and piezoelectric coefficients. Prototype transducers were built using shear type lithium niobate crystals. The initial ultrasonic experiments show that it can be used at temperatures up to 450°C to transmit and receive guided wave signals at 70 kHz. This will enable design and manufacture of high temperature transducers for continuous guided wave monitoring of power plants.
Gas Sensing Performance of Macroporous SnO2 Thin Film Prepared by Using Carbonaceous Polysaccharide Microspheres as Pore-Forming Agent
Authors: Zhou Dong Xiang , Gan Lu , Fu Qiu Yun , Gong Shu Ping , Liu Huan , Luo Wei , Zhao Jun
Published: March 2013

The macroporous SnO2 thin film has been successfully prepared on alumina substrate with printed Ag interdigital electrodes by sol-gel dip-coating method. The carbonaceous polysaccharide microspheres synthesized by hydrothermal method were used as pore-forming agent. The SnO2 thin film prepared without using carbon microspheres was also synthesized for comparison. X-ray diffraction and scanning electron microscopy were taken to study the micro-characteristics of samples. The influences of operating temperature, gas concentration and structure feature on the H2S sensing performance of SnO2 thin film samples were systematically studied. Compared with SnO2 thin film prepared without using carbon microspheres, the macroporous SnO2 thin film showed a considerably reduced recovery time and good response-recovery properties.
Synthesis and Kinetic of Palladium Nanotube Using Polymer Compound
Authors: Lee Jong Ho , Chi Choong Soo , Oh Han Jun
Published: March 2013

The palladium nanotube was synthesized by template wetting and annealing process. And the activation energy for formation of the palladium metal from palladium acetate was evaluated. The activation energy was evaluated by Friedman method and the values were in the ranges between 65 and 98 kJ/mol. The diameters and lengths of synthesized palladium nanotubes ranged from 130 to 190 nm and from 2 to 3 μm, respectively. The palladium nanotubes can be successfully fabricated by the template wetting process, and the crystalline structure is confirmed by XRD. From DSC results the thermal decomposition of precursor containing palladium acetate/PLLA occurred at 248°C, which corresponds to the precipitation of palladium metal.
Electrical Characterization of MOS Structures with Silicon Nanocrystals Suitable for X-Ray Detection
Authors: Mateos David , Nedev Nicola , Nesheva Diana , Curiel Mario , Manolov Emil , Arias Abraham , Contreras Oscar , Valdez Benjamin , Levi Zelma , Siqueiros Jesus M.
Published: March 2013

Metal-Oxide-Semiconductor structures with silicon nanocrystals in the oxide layer are prepared and characterized by Transmission Electron Microscopy and electrical measurements. High temperature annealing of SiO1.15 films at 1000 °C for 30 or 60 min leads to formation of silicon nanocrystals with diameters of 2-3 or 4-6 nm. The processes used to obtain the multilayer gate dielectric and to grow nanocrystals do not deteriorate the properties of the cSi wafer/thermal SiO2 interface. For the interface defect density and the fixed oxide charge values 1010 cm-2 eV-1 and ~ 1010 cm-2 were obtained.
Thermally Stimulated Discharge Currents of Poly(acrylonitrile-co-acrylic Acid)-Polypyrrole Composites
Authors: Cetiner S. , Olariu M. , Kaya N.U. , Aradoaei S.
Published: March 2013

Thermally Stimulated Discharge Currents, one of the oldest destructive method widely used for studying the mechanisms of polarization and depolarization within the dielectrics was employed for determining information related to trapped and/or detrapped charges and activation energy (Ea) within P(AN-co-AA)-PPy composite films. Two peaks or two relaxation regions could be noticed on the TSDC spectra for each material under test: one at a temperature around 323.15K (50°C), attributed to decomposition due to DMF removal as presented in our previous studies, and a second one at 363.15K (90°C), attributed to glass transition temperature. An increased of detrapped charges was observed when the PPy quantity within the P(AN-co-AA) matrix was increased. The same time, both relaxations appeared at very close temperatures for all three samples under test. Complementary measurements for an in-depth electrical analysis were performed with the help of Broadband Dielectric Spectroscopy (BDS), while further information regarding conductive composites structures was obtained through FTIR-ATR analysis.
A Generalized Method for Flat Plates Impact Detection and Location
Authors: Somolinos Jose Andrés , Morales Rafael , Morón Carlos , Garcia Alfonso
Published: March 2013

In the last years, many analyses from acoustic signal processing have been used for different applications. In most cases, these sensor systems are based on the determination of times of flight for signals from every transducer. This paper presents a flat plate generalization method for impact detection and location over linear links or bars-based structures. The use of three piezoelectric sensors allow to achieve the position and impact time while the use of additional sensors lets cover a larger area of detection and avoid wrong timing difference measurements. An experimental setup and some experimental results are briefly presented.
Fabrication of Monolithic Integrated Bimaterial Resonant Uncooled IR Sensor
Authors: Zhao D.Q. , Zhang Xia , Liu P. , Yang F. , Lin C. , Zhang D.C.
Published: March 2013

In this work we studied the fabrication of a monolithic bimaterial micro-cantilever resonant IR sensor with on-chip drive circuits. The effects of high temperature process and stress induced performance degradation were investigated. The post-CMOS MEMS (micro electro mechanical system) fabrication process of this IR sensor is the focus of this paper, starting from theoretical analysis and simulation, and then moving to experimental verification. The capacitive cantilever structure was fabricated by surface micromachining method, and drive circuits were prepared by standard CMOS process. While the stress introduced by MEMS films, such as the tensile silicon nitride which works as a contact etch stopper layer for MOSFETs and releasing stop layer for the MEMS structure, increases the electron mobility of NMOS, PMOS hole mobility decreases. Moreover, the NMOS threshold voltage (Vth) shifts, and transconductance (Gm) degrades. An additional step of selective removing silicon nitride capping layer and polysilicon layer upon IC area were inserted into the standard CMOS process to lower the stress in MOSFET channel regions. Selective removing silicon nitride and polysilicon before annealing can void 77% Vth shift and 86% Gm loss.
Electrical Properties and SEM Study of Foamed EBA/Carbon Black Composites
Authors: Pelíšková Michaela , Prokeš Jan , Pongprapat Piyamanocha , Slobodian Petr , Sáha Petr
Published: March 2013

Electrical properties and morphology of carbon black (CB) filled ethylene-butyl-acrylate copolymer (EBA) composites were studied in compact and chemically foamed versions. Conductivity percolation threshold for foamed composites was lowered by five weight percent of carbon black concentration. It means that the same conductivity values were achieved at reduced concentration of filler than for non-foamed version of composite. As a result semiconducting material with reduced density (weight) and content of carbon black is obtained. The sensitivity of foamed composite conductivity to mechanical stimulus induced by uniaxial compression was observed.
Measurement of Putting Golf Balls Motion Using a Vision Sensor
Authors: Kim Dong Joon , Pham Minh Nha , Ahn Hyeong Joon
Published: March 2013

This paper presents measurement of a putting golf ball jump motion using a vision sensor. After putting, a golf ball experiences bouncing, sliding and rolling sequentially. In particular, ball jump motion contains lots of important information related to impact such as jump number, height and length. Putting is simulated as a simple pendulum and golf ball jumps are measured using a vision sensor. The golf ball jump changes significantly according to impact errors such as impact timings. If an IMU sensor is attached on the putter head and relationship between variations of golf ball trajectory and IMU sensor signal is characterized, coaching information of golf putting to correct various impact errors can be provided only using IMU sensor.
Obtaining Highly Selective Responses from a Bulk Tin Oxide Gas Sensor
Authors: Hossein-Babaei Faramarz , Amini Amir
Published: March 2013

Generic gas sensors are commonly used for the detection of different airborne contaminants due to their high sensitivity, long life and low cost, but they generally suffer from the variety of drifts and the lack of selectivity. Different techniques have been developed for selectivity enhancement in metal oxide gas sensors, among which operating temperature modulation is well known. It has been observed that sharp pallet temperature changes provide more analyte-related information. Due to the high thermal capacitance of the device, applying step voltage pulses to a bulk tin oxide gas sensor fails to provide step pallet temperature variations. On the other hand, the low thermal capacity of the custom made microheater gas sensors renders them vulnerable to all kinds of thermal noise and agitations. A novel technique is reported for temperature modulation, which facilitates sharp temperature rises of the gas sensitive pallets in generic gas sensors [. In this technique, a sharp heating voltage spike, considerably surpassing the nominal heating voltage, is applied prior to each heating voltage step. The thermal impact of these spikes is adjusted by controlling v2dt for obtaining the closest variations to the ideal temperature profile. Here, the advantages and effectiveness of the technique are demonstrated by differentiating among iso-butanol, tert-butanol, 1-butanol and 2-butanol contaminations in a wide concentration range in air using only a single generic tin oxide gas sensor.
Magneto-Optical Investigation of Thin-Film Magnetic Structures
Authors: Tsidaeva Natalia , Abaeva Viktorija , Enaldieva Elena , Magkoev Tamerlan T. , Turiev Anatolij M. , Ramonova Aljona , Butkhuzi Tengiz , Tvauri I.V. , Khubezhov Soslan
Published: March 2013

After the discovery of antiferromagnetic interaction [, giant magnetoresistance [ and oscillating magnetic interaction [, the exchange coupling between magnetic layers across the conductive nonmagnetic spacer layer in multilayer structures have been attracted much attention [4-.
Structural, Electrical and Magnetic Investigations of Conductive ZnO: Co Thin Films Deposited by DC Reactive Magnetron Co-Sputtering
Authors: Lardjane Soumia , Yazdi Mohammad Arab Pour , Fenineche Noureddine , Merad G. , Feraoun H.I. , Billard Alain
Published: March 2013

Zn1-xCoxO (0 < x < 14.6) diluted magnetic semiconductor coatings have been obtained by reactive DC magnetron sputtering of metallic Zn and Co targets at high pressure and high temperature. The coatings structural properties have been investigated by X-ray diffraction. All as-deposited coatings are crystalized in ZnO structure and neither traces of metallic nor oxide Co-rich clusters were detected in the films. The temperature dependence of the magnetization shows a paramagnetic Curie-Weiss behavior with antiferromagnetic interaction due to the associated spins and simple paramagnetic curie behavior of isolated free spins.
Effect of Neutron Irradiation on Indium-Containing III-V Semiconductor Micromonocrystals
Authors: Bolshakova Inessa , Ďuran Ivan , Kost Yaroslav , Kovaljova Nelli , Kovarik Karel , Makido Olena , Sentkerestiová Jana , Shtabaliuk Agata , Shurygin Fedir , Viererbl Ladislav
Published: March 2013

The paper presents the results of the studies into the effect exerted by neutron irradiation on the parameters of microcrystals of III-V group semiconductor materials (InSb, InAs and their solid solutions). The values of optimum initial charge carrier concentration for each of the materials under research, which would allow them to retain maximum radiation resistance, have been determined. The obtained results can be employed in assessing the industrial semiconductor sensors operability in radiation environment.
Surface Treatments to Enhance the Sensitivity of Plastic Optical Fiber Based Accelerometers
Authors: Vallan Alberto , Grassini Sabrina , Perrone Guido
Published: March 2013

The paper presents an all-fiber accelerometer that uses plastic optical fibers and discusses the enhancement of its sensitivity through physical treatments on the polymer surface to modify the light propagation characteristics. Given the target of being low-cost and compact, the accelerometer exploits the variation of propagation loss induced by the deformations of a miniaturized cantilever on which the fiber is fixed. This simple setup, however, does not exhibit a sufficient sensitivity unless the fiber surface is properly treated in order to enhance the loss dependence with the cantilever bending. Two approaches are compared, namely plasma micro-and nanotexturing and laser localized ablations. Several prototypes of accelerometers have been fabricated using various types of plastic fibers and characterized using a vibration test facility. Preliminary results show that both techniques are effective and can produce similar results, although accelerometer made by laser localized ablation may be more suitable for industrial applications, like the monitoring of vibrations due to moving parts of machines.
Differential Surface Plasmon Resonance Sensor for the Detection of Chemicals and Biochemicals
Authors: Fallauto Carmelo , Perrone Guido , Vallan Alberto
Published: March 2013

Surface plasmon resonance is one the most common optical sensing techniques for the detection of chemicals and biochemicals, although still mainly confined to lab applications. Typically, these sensors are made by a thin gold layer deposited on a glass prism or on an optical fiber similar to those used in telecom applications. Key advantages of this technique are the possibility to specifically detect different chemicals through functionalization of the metal surface and the high sensitivity, although the latter may turn into a weakness in long term monitoring applications due to cross-sensitivity to parasitic effects. To overcome this limitation the paper proposes a novel sensor implementation with a cascaded double sensing area, particularly suited for long term monitoring of pollutant since one sensing area is actually used to detect the desired molecules, while the other for compensating drifts due to fluctuations, misalignments and temperature variations. The paper addresses mainly the prism-based implementation, but the proposed configuration is suited also for an all-fiber approach. Examples of practical implementation of the proposed techniques are given, evidencing an accuracy improvement of more than an order of magnitude.
Materials Bound by Non-Chemical Forces: External Fields and the Quantum Vacuum
Authors: Swain John , Widom Allan , Srivastava Yogendra N.
Published: March 2013

We discuss materials which owe their stability to external elds. These include: 1)external electric or magnetic elds, and 2) quantum vacuum uctuations in these elds inducedby suitable boundary conditions (the Casimir e ect). Instances of the rst case include theoating water bridge and ferrouids in magnetic elds. An example of the second case is takenfrom biology where the Casimir e ect provides an explanation of the formation of stackedaggregations or \rouleaux" by negatively charged red blood cells. We show how the interplaybetween electrical and Casimir forces can be used to drive self-assembly of nano-structuredmaterials, and could be generalized both as a probe of Casimir forces and as a means ofmanufacturing nanoscale structures. Interestingly, all the cases discussed involve the generationof the somewhat exotic negative pressures. We note that very little is known about the phasediagrams of most materials in the presence of external elds other than those represented bythe macroscopic scalar quantities of pressure and temperature. Many new and unusual statesof matter may yet be undiscovered.
Wireless Electromagnetic Communication Systems between Bacteria in Communities
Authors: Widom Allan , Srivastava Yogendra N. , Swain John
Published: March 2013

Bacteria, very old on an evolutionary scale, can live within agricultural soils wiredtogether into communities. The information content transferred through the wires is not yetentirely clear. It has recently been discovered that, younger on the evolutionary scale, E. colibacteria can live in communities with wireless communication systems. E. coli bacteria containDNA macromolecules in the form of a closed loops. The DNA molecules are coated with coherentwater shells having semiconducting properties. The electron energy levels when moving withinthe DNA water shells can be invoked to explain the broadcast and reception frequency spectraof the wireless bacterial systems.
Localized Surface Plasmon Resonance Sensor Using Gold Nanoparticles for Detection of Bisphenol A
Authors: Bakar Norhayati Abu , Salleh Muhamad Mat , Umar Akrajas Ali , Yahaya Muhammad
Published: March 2013

This paper reports an attempt to develop an optical sensor system to detect Bisphenol A (BPA) in water based on plasmonic property of Gold Nanoparticles (GNPs). Spherical GNPs of the average size of ca. 31±7 nm were grown on quartz substrate using seed mediated growth. An optical sensor system was setup, comprises a tungsten lamp light source, a duplex fiber optic probe, a spectrometer and a sensor chamber. Detection of BPA was done by comparing the Localized Surface Plasmon Resonance (LSPR) spectra of the GNPs film immersed in the deionised water and in BPA solutions by varying the concentration of BPA solutions from 58 mg/L to 0.003 ng/L. The LSPR spectra of GNPs sample were very sensitive to the presence of BPA where the shifted of their peaks position and the changed of their intensities are increases with the concentration of the BPA solutions.
Study of Local and Transient Buckling in Glass Fiber Reinforced Composite Using Fiber Bragg Grating
Authors: Melemez F. Fatih , Boz Talha , Chelliah Pandian , Bektas Gokhan , Yildiz Mehmet , Ozturk Cem , Menceloglu Yusuf Z.
Published: March 2013

Glass ber reinforced composites (GFRC) are widely used in load bearing industrialapplications. Failure can occur in GFRC due to matrix cracking, ber breaking, crack coupling,delamination, or combined e ects of these failure mechanisms, and it is important to study thefailure mechanisms for qualitative inspection of the material during its operation. In this paper,GFRC is manufactured using resin transfer molding, and ber Bragg grating is embeddedin the composite during the manufacturing step. A strain gage is surface mounted on thecomposite, to correlate the FBG measurement data. GFRC is subjected to continuous tension-compression load cycles at 1Hz using MTS 322 test-frame servo-hydraulic test machine. TheFBG is characterized in this loading regime, and its strain sensitivity calculated. The cyclicloading induces local buckling the composite. It is observed that the buckling does not leadto immediate failure. However, the initial local buckling is transient in nature and surfaces atcompression stage of the loading cycle. Continuous loading cycles, leads to permanent bucklingin the composite leading to complete failure of the composite, and is observed in real-time usingFBG.
Fabrication of Magnetic Tips for High-Resolution Magnetic Force Microscopy
Authors: Futamoto Masaaki , Hagami Tatsuya , Ishihara Shinji , Soneta Kazuki , Ohtake Mitsuru
Published: March 2013

Effects of magnetic material, coating thickness, and tip radius on magnetic force microscope (MFM) spatial resolution have been systematically investigated. MFM tips are prepared by using an UHV sputtering system by coating magnetic materials on non-magnetic Si tips employing targets of Ni, Ni-Fe, Co, Fe, Fe-B, and Fe-Pd. MFM spatial resolutions better than 9 nm have been confirmed by employing magnetic tips coated with high magnetic moment materials with optimized thicknesses.