bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Contractile Activity of Substituted 1,2,3,4-Tetrahydroisoquinolines
Authors: Ivanov Iliyan , Nikolova Stoyanka , Aladjov Dimo , Stefanova Iliyana , Zagorchev Plamen
Published: August 2011

A series of different 1-monosubstituted and 1,1-disubstituted 1,2,3,4-tetrahydro-isoquinolines was synthesized in high yields from different ketoamides. We have developed a convenient method for the synthesis of disubstituted derivatives by interaction of ketoamides with organomagnesium compounds, followed by cyclization in the presence of catalytic amounts of p-toluenesulfonic acid (PTSA). A number of substituents at the C-1 in the isoquinoline skeleton were introduced varying either carboxylic acid or organomagnesium compound. Some of the obtained 1,1-dialkyl-1,2,3,4-tetrahydro-isoquinolines possess contractile activity against guinea pig’s gastric smooth muscle preparations.
Effect of Pregnancy on Ankylosing Spondylitis: A Case-Control Study
Authors: LUI NAI LEE , HAROON NIGIL , CARTY ADELE , SHEN HUA , COOK RICHARD J. , SHANMUGARAJAH SUTHA , GLADMAN DAFNA D. , INMAN ROBERT D.
Published: August 2011

Objective.

To evaluate the effect of pregnancy on ankylosing spondylitis (AS).

Methods.

Our study aimed to determine the severity of back pain and stiffness pre-, during, and postpartum in patients with AS and controls, and corresponding extraarticular symptoms.

Results.

Nineteen female patients with AS (35 pregnancies) and 33 controls (77 pregnancies) were studied. Improvement in pain was reported in 51% of AS patients, predominantly in the first trimester, with significant improvement in pain than stiffness. In both groups, pain worsened in later stages, likely secondary to biomechanical loading. Postpartum pain scores in AS returned to prepartum levels in general.

Conclusion.

Pregnancy does not substantially aggravate disease activity or severity in AS.
Modelo para la evaluación de ontologías. Aplicación en Onto-Satcol
Authors: Senso Jose A. , Leiva-Mederos Amed Abel , Domínguez-Velasco Sandor Eduardo
Published: August 2011

Se analizan los referentes teóricos y conceptuales de la evaluación de ontologías para conocer los procedimientos utilizados en la evaluación de estos sistemas y establecer nuevas pautas para calibrar el sistema ontológico empleado por el programa Satcol, especializado en Ingeniería de Puertos y Costas. En el trabajo se describen las características de la ontología Onto-Satcol y se evalúa la misma mediante el uso de varios indicadores (léxicos, de recuperación de información y de la estructura sintáctica). Mediante un experimento llevado a cabo por 6 expertos, y con la ayuda de la herramienta Protex, se identifican inconsistencias semánticas, estructurales y errores en la organización del conocimiento de dicha ontología.
Evaluación de redes tecnocientíficas: la red española sobre Áreas Protegidas, según la Web of Science
Authors: Pino-Díaz José , Jiménez-Contreras Evaristo , Ruíz-Baños Rosario , Bailón-Moreno Rafael
Published: August 2011

Las relaciones de coocurrencia entre las palabras clave, los investigadores y las revistas en los artículos científicos de un dominio documental concreto confi guran una red tecnocientífica que puede ser analizada y cartografiada para conocer los nodos, subredes y áreas de investigación estratégicas, relevantes o importantes. Se ha realizado el análisis estratégico y el análisis dinámico, de traducción o de cambio, de la Red de Investigación Española sobre Áreas Protegidas según la Web of Science en el período 1981-2005. Producto de este análisis se han obtenido el Diagrama Estratégico y el Mapa de Conocimiento Estratégico de la Red Tecnocientífica o Mapa CERT, los listados de investigadores y de revistas de importancia estratégica y la tabla de análisis de actividad de las subredes. La red tecnocientífica analizada es una red bien estructurada, en la que se han identificado veintidós subredes estratégicas de investigación. El análisis de las redes tecnocientíficas mediante técnicas de creación de nuevo conocimiento a partir de bases de datos bibliográficas y de ingeniería y cartografía del conocimiento supone un apoyo de primer orden a la toma de decisiones estratégicas en Política Científica y en evaluación de la Ciencia y de la Tecnología.
Certificación de calidad en los archivos. Análisis y prospectiva
Authors: Moro Cabero Manuela
Published: August 2011

Análisis del alcance de la certificación en la práctica archivística. Descripción del proceso certificador, de la normativa específica utilizada para ello y de los organismos certifi cadores, con el fin de mostrar su funcionamiento y difundir fuentes y agentes que intervienen en la certificación de Archivos. Contextualización de la certifi cación en el modelo de gestión de documentos —serie ISO 30300—, sistema de gestión para los documentos, con el objetivo de difundir sus principios y estructura donde se regula su certificación. Valoración del impacto de la certificación sobre el mantenimiento de sistemas de gestión documental eficientes en las organizaciones. El método analítico-descriptivo es utilizado en el estudio, cuyos resultados son: descripción del(los) objeto(s) y proceso de certificación en el Archivo. Presentación del proyecto de certificación regulado en la serie de normas ISO 30300 sobre sistemas de gestión documental: objeto, proceso y agentes implicados. Reflexión sobre el impacto del proceso certificador de la actividad de archivar en las organizaciones.
Mejora del rango dinámico en la digitalización de documentos desde una perspectiva patrimonial: evaluación de métodos de alto rango dinámico (HDR) basados en exposiciones múltiples
Authors: Robledano Arillo Jesús
Published: August 2011

Uno de los principales problemas de calidad en la digitalización de documentos, especialmente de carácter gráfico, es la falta de rango dinámico en los dispositivos de captura. Una posible vía de trabajo para evitarlo es la aplicación de técnicas de alto rango dinámico (HDR) basadas en la fusión de múltiples capturas tomadas a diferentes exposiciones. Si se demuestra la idoneidad de estas técnicas en el contexto del patrimonio documental, podrían obtenerse capturas digitales de gran calidad con el empleo de equipamiento de menor coste y fácilmente asequible para instituciones con pocos recursos económicos. En este trabajo se realiza una aproximación teórica y experimental al concepto y métodos de evaluación de la calidad en la digitalización de documentos, la incidencia en la calidad del rango dinámico, y la viabilidad del uso de técnicas HDR en la digitalización de documentos con valor patrimonial.
Virtual Modeling and Finite Element Analysis of Flexspline Based on Solidworks
Authors: Zhang Rong , Yang Jia Jun
Published: August 2011

In harmonic gear mechanism, flexspline’ stress state have a direct impact on selecting wave generator as middle flexible components, this paper firstly simplify flexspline model, construct theory models, then simulate flexspline to compare and analyze in different wave generator, through this，we can select reasonable structure of wave generator from harmonic gear mechanism, provides a new method to design harmonic gear mechanism.
The Longitudinal Vibration Analysis of the Drive Screw Under the Elastic Supports
Authors: Zhang Hui Duan , Sun Jun Ling
Published: August 2011

The ball screw drive system is obtained widespread application in the modern machine. Along with the improving of feeding velocity and working precision, its dynamic analysis becomes more and more important. Considering the bearing stiffness and the contact deformation between the worktable and the screw, the drive screw is seen as a bar under elastic supports at both ends and with an internal moving elastic support. Using boundary conditions and matching conditions, the longitudinal vibration frequency equation of the screw is derived and the mode shape of the screw is solved. The vibration frequency is analyzed when the worktable moves from the left to the right end of the screw. The effect of the system parameters on the natural frequency and the mode shape are studied to supply a base for designing the drive system.
Dynamic Properties Analysis of Compliant Foil Aerodynamic Bearings Based on Spring Model
Authors: Liu Si Xing , Ma Xi Zhi
Published: August 2011

The dynamic coefficients are the essential parameters, which could be used to determine the critical rotational speed, an unbalance response and the stability analysis. A plural mathematic model of the coefficients calculation is developed by using the numerical perturbation method. A spring model is applied to get the foil deformation. The dynamic coefficients of the gas foil bearings are obtained through the application of the finite difference method and the finite element method. The results show that the dynamic coefficients are closely related to the journal eccentricity and whirl ratio. With the results compared to the published data, the model is proved to be accurate. And the coefficients could be used as a reference for the design of a gas foil bearing.
Research on Helicopter Main Gearbox Operating without Oil
Authors: Liao Mei Jun , Su Xin Sheng , Yang Zhen Rong , Yao Bo
Published: August 2011

According to analysis factors that influence the oil loss capability of main gearbox, this paper researches on weakness of the main gearbox operation without oil. Then the method to improve the weakness is introduced, and the improvement is proved valid by test. The advice in this paper can be important reference and guidance to improve the oil loss capability of main gearbox.
Current Development Situation and Prospect of Circular-Arc Gear
Authors: Gao Hong Mei , Liu Yang , Chen Yuan , Liu Shi Jun
Published: August 2011

This article introduced the current development situation and prospect of circular-arc gear in China from the following aspects: theory of engagement, the gear strength, advanced processing technology, accuracy and measurement, and application of circular-arc gear. It indicates that the carburized hardened grinding double circular-arc gear transmission, as one of the promising transmission types, have the possibility to break through the load capacity limitation of current gear transmission.
Operational Modal Test for Wind Turbine Gearbox
Authors: Zheng Zhan Qiang , Shi Wan Kai , Liu Kai You
Published: August 2011

Wind turbine gearbox is a key component of wind power system and it is prone to failure because of complex working environment, so the vibration and noise problems of it can not be ignored. The modal parameters of gearbox can be got by experiment method, which is a necessary condition to improve the structure of gearbox and make dynamic analysis and design to it. Modal testing has been used to gearbox by operational modal analysis which is in several actual working conditions and the modal parameters in corresponding working conditions is obtained by stochastic subspace identification. Meanwhile the acceleration response of wind turbine gearbox’s high-speed output shaft in different working conditions was also analyzed.
The Optimization Design for Rack Tooth Profile Curve of Straight Push-Rod Linear Reducer
Authors: Zhou Chuan Xi , Huang Qing Shi , Guan Feng
Published: August 2011

The straight push-rod linear reducer is a new kind of transmission installation, the rack is the key link of the mechanism. Here the author have discussed the establishment of optimization mathematical model about rack tooth profile curve when the linear reducer are used in different occasion, and also have introduced the adopted optimization methods, finally have analyzed the optimal result of tooth profile curve of two specific conditions. In the end, through the comparison about some corresponding indexes of tooth profile between the optimal result and a few commonly used curve, the optimal tooth profile got by the optimal solution is verified the optimal result.
Influence Factors and Calculating Methods for Gear Windage Power Loss
Authors: Ge Yu Zhu , Lei Xue Mei , Zhang Yue Chun , Liu Ping
Published: August 2011

Based on making some analyses and comparisons about influence factors and existing calculating methods for gear transmission windage loss, it gives practical area and application situation of these calculating methods in this paper. Also it presents some suggestions on some possible problems when calculation. The results can provide a basic reference and guidance to evaluate and optimize design for designer.
Optimization of New Type Sintering Machine’s Sprocket Wheel with Even-Number Teeth
Authors: Bai Ming Hua , An Li Bao , Ren Su Bo , Wang Li Jun
Published: August 2011

Comprehensive consideration the even teeth sintering machine’s pallet car and the smooth and continuous meshing of variable acceleration segment of the sprocket wheel’s tooth profile, puts forward a new type sprocket wheel’s tooth profile to make variable acceleration segment’s unified equation. According to the displacement, velocity and acceleration’s curves of the pallet car in the stage of variable acceleration, with the method of locus of the contact new tooth profile’s equation is deduced. The sprocket wheel which is derived by this method is stability in variable speed process, concise, easy to manufacture and analyze the characteristics equation of tooth profile.
Manufacturing Method of Long-Cone-Distance Spiral Bevel Gears Based on CNC Machining Center
Authors: Lei Bao Zhen , Zhang Bin , Zhang Hua
Published: August 2011

A method is presented for producing long-cone-distance spiral bevel gears using CNC machining center. Due to long-cone-distance, these spiral bevel gears are very difficult to produce, because machine-tool settings exceed the outermost limits of the available dedicated machines. The method removes the limits of the dedicated machine tool. This paper consists of (a) geometric modeling of the long-cone-distance spiral bevel gears, (b) process planning for NC machining based on CAM software. Experimental cuts were made to ascertain the validity and effectiveness of the presented method with a CNC machining center.
Comparison of Digitized Images for Cephalometric Analysis from Scanner and Digital Cameras
Authors: Anuwongnukroh Niwat , Dechkunakorn Surachai , Sinthanayothin Chanjira , Shinawatra Lada
Published: August 2011

Objective: The aim of the study was to compare the manual tracing of lateral cephalometric radiographs with the use of cephalometric software obtained by 2 methods: use of a scanner and use of cameras to test the accuracy of measurement for clinical orthodontic diagnosis. Material and Methods: The original method of manual tracing was compared to 2 radiographic digitization methods: A) captured from a scanner, B) captured from digital cameras applied to 40 randomly selected cephalograms of orthodontic patients at Mahidol University. The digital images from cameras and scanner were analyzed with image processing software (CephSmile). The repeatability test was obtained for all methods, and the paired t-test determined the statistical significance between digitized images and original manual tracings for thirty-four measurements. Results: The paired t-test showed no significant differences among all 34 variables. Most mean differences were less than 0.25 mm and 0.25 degrees. Conclusion: The results demonstrated that there were no significant differences on measurement parameters for cephalometric analysis among manual tracing and computerized digital images from scanner and cameras.
High-Temperature Response of TiC Particulate Reinforced Titanium Matrix Composite
Authors: Song Wei Dong , Ning Jian Guo , Mao Xiao Nan
Published: August 2011

The high-temperature mechanical behavior of TiC particulate-reinforced titanium matrix composites was investigated at elevated strain rates. The effects of the temperature and strain rate on the mechanical properties of the composites were analyzed. According to Arrhenius flow stress model, a dynamic-high-temperature constitutive relation of TiC particulate-reinforced titanium matrix composites was established.
Microstructure and Strengthening Mechanisms of Oxide Dispersion Strengthened Ferritic Alloy
Authors: Lee Jae Hoon
Published: August 2011

Oxide dispersion strengthened (ODS) ferritic alloys of composition Fe-19Cr-0.5Y2O3have been prepared by mechanical alloying at various heat-treatment conditions to produce a range of grain sizes and dispersed oxide particle size. Fine oxide particles appear to pin grain boundaries and result in inhibition of grain growth in the alloy matrix. Particle strengthening is shown to be a larger component of the material strength, rather than grain boundary strengthening or matrix strength, indicating that the finely dispersed oxide particles contribute very significantly to the total strength of 19Cr-ODS ferritic alloy.
Radial Oscillation of Incompressible Rectangular Vulcanized Rubber Sealing Rings
Authors: Yuan Xue Gang , Niu Da Tian , Cong Shu Qiang , Liu Xiao Wei
Published: August 2011

The oscillation problem is examined for a rectangular sealing ring composed of a class of transversely isotropic incompressible vulcanized rubber materials about radial direction, where the sealing ring is subjected to a suddenly applied radial load at its inner surface. A nonlinear ordinary differential equation that describes the radial motion of the sealing ring is obtained. It is proved that if the applied load is lower than the critical load, the motion of the rubber ring with time will present a nonlinear periodic oscillation, while if it exceeds the critical load, the motion will increase infinitely with the increasing time and so the rubber ring will be destroyed ultimately.
Layup Analyzing of a Carbon/Glass Hybrid Composite Wind Turbine Blade Using Finite Element Analysis
Authors: Lin Hai Chen
Published: August 2011

This thesis use AOC15/50 blade as baseline model which is a composite wind turbine blade made of glass/epoxy for a horizontal axis wind turbine. A finite element modeling of composite wind turbine blade was created using the SHELL element of ANSYS. Then we study how to use the carbon fiber material replaces the glass fiber to make the hybrid blade, and find a suitable layup to improve the performance of the blade. The hybrid blade was made through introducing carbon fibers. Different models, with introducing different number of carbon fibers, 75% carbon fibers replace unidirectional glass fibers in spar cap of blade model which can achieve best structure performance. The wind turbine blades are often fabricated by hand using multiple of glass fiber-reinforced polyester resin or glass fiber-reinforced epoxy resin. As commercial machines get bigger, this could not to meet the demands. The advantages of carbon fiber composite materials are used by blade producer. Studies show that carbon fiber has high strength-to-weight ratio and resistance fatigue properties. Carbon fiber is mixed with epoxy resin to make into carbon fiber-reinforced polymer. Carbon fiber-reinforced polymer is the one of best blade materials for resistance bad weather. The stiffness of carbon fiber composite is 2 or 3 times higher than glass fiber composite [1], but the cost of carbon fiber composite is 10 times higher than glass fiber composite. If all of wind turbine blades are made of carbon fiber composite, it will be very expensive. Therefore carbon/glass fiber hybrid composite blade has become a research emphasis in the field of blade materials. This paper gives an example of finite element modeling composite wind turbine blade in ANSYS by means of the medium-length blade of AOC 15/50 horizontal axis wind turbine. This model can be directly used in dynamics analysis and does not need to be imported from the CAD software into finite element program. This finite element modeling of composite wind turbine blade was created using the SHELL element of ANSYS. Then we study how to use the carbon fiber material replaces the glass fiber to make the hybrid blade, and find a suitable lay-up to improve the performance of the blade.
Experimental Investigation a Hydrofoil Lift Characteristic under the Action of Lorentz Force
Authors: Chen Yao Hui , Fan Bao Chun , Chen Zhi Hua
Published: August 2011

Experiments study the Hydrofoil Lift Characteristic under the Action of Lorentz Force. With the streamwise wall-parallel Lorentz force applied on the whole suction side of the hydrofoil, The results show that the flow separation can be suppressed completely and the lift of hydrofoil is increased. The higher the Lorentz force, the larger the lift. It is also demonstrated that the Lorentz force actuator equipped on the front of the hydrofoil is more effective on the lift increase than that equipped on the tail.
Effect of Gypsum on Hydration Degree and Structure of Hardened Paste of Alite-Strontium Calcium Sulphoaluminate Cement
Authors: Li Qiu Ying , Lu Ling Chao , Wang Shou De
Published: August 2011

Synthesis conditions and performance of alite-strontium calcium sulphoaluminate cement have been studied by introducing strontium calcium sulphoaluminate into Portland cement clinker. The effects of gypsum on compressive strength, hydration degree and structure of hardened alite-strontium calcium sulphoaluminate cement paste were studied in this paper. Composition and structure of the hardened cement paste were analyzed by XRD and SEM. Results show that appropriate content of gypsum could contribute to the hydration of alite-strontium calcium sulphoaluminate cement. When gypsum content is 9%, the compressive strengths for 1d, 3d and 28d curing age are 30.7MPa, 59.5MPa and 105.5MPa, and the corresponding hydration degree are 40.4%, 57.5% and 85.8%, respectively. The hydration products of alite-strontium calcium sulphoaluminate cement are mainly ettringite (AFt), Ca(OH)2, C-S-H gel. Large amount of AFt formed at early curing age provides a sound basis for early compressive strength, and a lot of C-S-H gel generated at later curing age increases the density of the hardened paste.
Study of Adsorptive Behaviors of Aminosulfonic Acid-Based Superplasticizer on the Calcium Sulphoaluminate Mineral
Authors: Liu Tong , Li Yan Jun , Li Bao Liang , Wu Yuan Chao , Wang Wei Shan , Liu Xiao Cun
Published: August 2011

Calcium sulphoaluminate (3CaO·3Al2O3·CaSO4, ) was synthesized with pure chemical reagents. The adsorbed amount of aminosulfonic acid-based superplasticizer (AS) on the surface of mineral and the mineral mixture (mixture of the , Ca(OH)2and CaSO4·2H2O) were detected by ultraviolet-visible absorption spectrometry. The adsorptive behaviors of AS on the surface of mineral particles in the hydration system were studied. The results showed that: the adsorbed amount of AS on mineral and the mineral mixture increased with higher initial concentration; the adsorption amount and the maximum adsorption amount increased with prolonged hydration time; the adsorption amount and the maximum adsorption amount of AS on the mineral mixture was more than those on the mineral in the hydration system within the same hydration time.
Synthesis, Photophysical Properties and Aggregates of a New Pyridinium Dye
Authors: Sun Yun Hui , Deng Yun Long , Cao Du Xiao , Liu Zhi Qiang
Published: August 2011

A new pyridinium dye, 2-{2-[9-ethyl-carbazole-3-yl]vinyl}-N-(3-sulfooxypropyl) pyridinium inner salt, has been synthesized. The photophysical properties of the dye in DMF were investigated. The dye exhibits strong orange fluorescence with quantum yield Φ = 0.1. The particles are nano-scale after 30minutes, but it will accumulate to micron-scale after 4h.
Fabrication of Anti-Reflective Coatings on Solar Collector Tubes
Authors: Niu Yu Chao , Huang Guo Wei , Chen Ying , Dou Wen Wen , Sun De Ming , Li Jing
Published: August 2011

In order to reduce the reflection of solar collector cover tube and improve its transmissivity, a kind of SiO2anti-reflective coating on the cover tube was prepared using acid-base two-step sol-gel method. The surface morphology of the anti-reflective coating was observed using atomic force microscope and electronic scanning microscope. The scratch resistance of the coating was tested using pencil hardness apparatus. The transmissivity and anti-impact properties of the cover tube coated with the coating were measured respectively by means of the spectrophotometer and the relative standard method. The results showed that the anti-reflective coating possesses a higher scratch resistance and the coated cover tube has good transmissivity and anti-impact.
Electron Microscopy Study of Y-Shaped Carbon Fibers with Different Morphologies
Authors: Zhang Qian , Dong Li Feng
Published: August 2011

A series of techniques, including field emission scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, and energy dispersive X-ray spectroscopy were employed to investigate three types of Y-shaped carbon fibers that were synthesized by the thermal decomposition of acetylene using an atmospheric pressure catalytic chemical vapor deposition process and copper tartrate as a catalyst precursor. On the basis of electron microscopy analysis, we propose that the simultaneous growth of three pieces of carbon fibers on the same copper catalyst particle results in the formation of Y-shaped carbon fibers. When several copper catalyst particles became positioned in a stratified arrangement, other types of Y-shaped carbon fibers were obtained. Our study indicates that the morphology of various Y-shaped carbon fibers can be controlled by tailoring the configuration of the copper catalyst particles used to generate them.
Fluorescent Sensors for Nitroaromatic Compounds Based on the Comb-Like Polysiloxane-Acrylate
Authors: Cui Yue Zhi , Ren Xiao Liang , Dong Xue Ming , Wang Yong Tao
Published: August 2011

A functional polysiloxane monomer, with a double bond and a fluorophore pyrene at each end of the polysiloxane chain, respectively, was synthesized. Copolymerize this functional monomer with other acrylates in emulsion, we got a comb-like polymer in which pyrene fluorophore is at the end of each polysiloxane side-chain. This polymer shows great advantage in sensing performance for 2,4-dinitrotoluene (DNT) over its analog that was prepared just by mixing pyrene with pure polyacrate emulsion.
Luminescence in Rare Earth Activated AlPO4 Phosphor
Authors: Shinde K.N. , Dhoble S.J.
Published: August 2011

Rare earth activated AlPO4 phosphors were synthesized by solid-state reactions and the completion of the synthesis was confirmed by X-ray diffraction (XRD) pattern. Under near-ultraviolet (nUV) light, the Eu3+ emission in AlPO4 consists of the transitions from 5D0 to 7FJ shows orange/red region and the AlPO4 :Dy3+ phosphor shows an efficient blue and yellow band emissions, which originates from the 4F9/26H15/2 and 4F9/26H13/2 transitions of Dy3+ ion. The excitation spectra of the phosphors are extending from 300 to 400 nm, which are characteristics of nUV excited LED. The effect of the Eu3+ and Dy3+ concentration on the luminescence properties of AlPO4 phosphors is also studied.
Characteristics of Gamma–Ray Irradiated Pentacene Organic Thin Film Field Effect Transistors
Authors: Yano Hiroaki , Cai Li , Hirao Toshio , Duan Zong Fan , Takayanagi Yutaro , Ohuchi Hirokuni , Ueki Hideharu , Ohshima Takeshi , Nishioka Yasushiro
Published: August 2011

P-channel pentacene field effect transistorswith a Si/SiO2/pentacene/Au structure were fabricated, and were gamma-ray irradiated with a Co60source. The changes of the drain current IDvs. source/drain voltage VSD(ID- VSD) characteristics were measured after every 200 Gy in silicon (GySi) irradiations up to the total dose of 1200 GySi. The drain current IDcontinuously decreased to less than 10 % of that before irradiation after 1200 GySiirradiation. The threshold voltage Vthcontinuously decreased up to 800 GySi, started to saturate above 800 GySi,and recovered above1000 GySi. The mobility m continued to decrease up to 1200 GySi. Those behaviors were explained by accumulation of positive trapped charge within the gate insulator SiO2near the interface, continuous increase of interface traps near the interface between the SiO2and pentacene, and build up of electrons in the channel regions. These behaviors were discussed in comparisons with previously reported results on ultraviolet (UV) light irradiation experiments on similarly structured pentacene-based transistors.
Promising Zn3Ta2O8:Pr3+ Red Phosphor for Low Voltage Cathodoluminescence Applications
Authors: Pitale Shreyas S. , Noto L.L. , Nagpure I.M. , Ntwaeaborwa O.M. , Terblans J.J. , Swart Hendrik C.
Published: August 2011

Zn3Ta2O8 is a promising host for low voltage cathodoluminescence (CL) applications. Surface chemical stability during low voltage electron beam excitation is a prime concern for phosphors to be used in various new generation information displays. Photoluminescence (PL) and CL characteristics of the Zn3Ta2O8 host doped with Pr3+ are presented. The phosphors were synthesized via solid-state reaction route at 1100°C. Red CL or PL with a maximum at 611 nm, attributed to the 1D2-3H4 transition of the Pr3+ ion, was observed at room temperature under high energy electron (2 keV, 12 μA) or a monochromatic xenon lamp (257 nm) irradiation. Electron stimulated chemical changes on the surface of the Zn3Ta2O8:Pr3+ phosphor during an electron beam exposure from 0-350 C/cm2 was monitored using Auger electron spectroscopy. The CL exhibited only a 20% loss in the original intensity during the continuous electron beam exposure. X-ray photoelectron spectroscopy (XPS) was used to estimate the redox states of the chemical constituents and a comparison of binding energies was made with the standard Ta2O5 and ZnO compounds. A correlation between the structural configuration of Zn3Ta2O8 and the XPS data is also established.
The Range Distribution of Nd Ions Implanted in Silicon-on-Insulator
Authors: Liang Yi , Li Hong Zhen , Li Shuang , Wang Feng Xiang , Qin Xi Feng
Published: August 2011

In view of the influence of the projected range, the range straggling, and the lateral deviation of ions in materials on the property of photoelectric integration devices fabricated by ion implantation, the mean projected ranges and range straggling for energetic 200 – 500 keV neodymium (Nd) ions implanted in silicon-on-insulator (SOI) at room temperature were measured by means of Rutherford backscattering followed by spectrum analysis.The measured results are compared with Monte Carlo code (SRIM2006) predictions. Our results show that the measured values of the mean projected rangeRpare good agreement with the SRIM calculated values; for the range straggling ΔRp, the difference between the experiment data and the calculated results is much higher than that ofRp.
Magneticbead-Based Enzyme-Linked Immunoassay for Detection Carcinoembryonic Antigen in Gastric Cancer Cells
Authors: Xia Fang Quan , Yuan Yan Ni
Published: August 2011

A sensitive immunoassay based on immunomagnetic beads for measuring carcinoembryonic antigen (CEA) concentration in cancer cells was presented in this article. We used immunomagnetic beads to separate CEA in the gastric cancer cells and those CEA could be marked with horseradish peroxidase (HRP) labeled anti-CEA secondary antibody. The HRP could catalyze non-fluorescent 10-acetyl-3,7-dihydroxyphenoxazine (ADHP) with hydrogen peroxide (H2O2) to fluorescent products. Therefore, the CEA concenctration was quanlified by flourescence intensity at 585 nm emission wavelength. The flourescence intensity of the product responged well linearly to CEA concentration in the range from 3.0 to 60 ng/mL with a lower detection limit of 1.5 ng/mL(3σ). This method could be applied to determine tumor markers in gastric cancer cells.
Dry Sliding Wear Behavior of Hot Pressed Fe-28Al and Fe-28Al-10Ti Alloys
Authors: Li Jing , Fan Xiao Hong , Sun De Ming
Published: August 2011

Fe-28Al and Fe-28Al-10Ti alloys were prepared by mechanical alloying and hot pressing. The phases and dry sliding wear behavior were studied. The results show that Fe-28Al bulk materials are mainly characterized by the low ordered B2 Fe3Al structure with some dispersed Al2O3 particles. Fe-28Al-10Ti exhibits more excellent wear resistance than Fe-28Al, especially after long distance sliding wear test. There are obvious differences in wear mechanisms of Fe-28Al and Fe-28Al-10Ti alloys under different testing conditions. Under the load of 100N, there is plastic deformation on the worn surface of Fe-28Al. The main wear performance of Fe-28Al-10Ti is particle abrasion, the characteristics of which are micro cutting and micro furrows, but micro-crack and layer splitting begin to form on the surface of Fe-28Al. Under the load of 200N, serious plastic deformation and work-hardening lead to rapid crack propagation and eventually the fatigue fracture of Fe-28Al. Plastic deformation is the main wear mechanism of Fe-28Al-10Ti under the load of 200N, which are characterized by micro-crack and small splitting from the worn surface.
Semisolid Die-Casting Process of Mg-20Al-0.8Zn Magnesium Alloy
Authors: Yan Feng Yun , Huang Xiao Feng , Li Bo , Ma Ying
Published: August 2011

Based on microstructure evolution of Mg-20Al-0.8Zn magnesium alloys realized by semisolid isothermal heat-treatment (SSIT), we obtained the non-dendrite or spherical grains microstructure under the suitable technological parameters that isothermal temperature is 495 °C and holding time is 120 min. With the help of special experimental equipment, the semisolid die-casting process has been studied and the specimens have been analyzed. The effects of different parameters as injection speed and pressure on tensile strength, elongation rate, hardness, etc have been investigated. The results indicate that tensile strength was improved along with increasing injection speed and pressure. However, excessive speed will involve gas, which formed defects and reduced the mechanical properties. When the injection pressure is 40MPa and injection speed is 4m/s, the tensile strength and elongation rate can reach maximal 220MPa and 5.63% respectively. Its fracture mechanism was intercrystalline cracking.
Synthesis, Characterization and Selective Recognition of Lead Using a New Ion Imprinted Polymer Material
Authors: Zhuang Hai Yan , Li Hui Zhi , Xue Yang
Published: August 2011

A new ion-imprinted polymer (IIP) material was synthesized by copolymerization of 4-vinylpyridine(VP) as monomer, ethylene glycol dimethacrylate(EGDMA) as crosslinking agent and 2,2΄-azobisisobutyronitrile(AIBN) as initiator in the presence of Pb–1,5-diphenylcarbazone(Pb-DHCB) complex. Blank non-imprinted polymer (NIP) were prepared under identical conditions without the use of lead imprint ion. The synthesized polymers were characterized by IR spectroscopy and elemental analyzer techniques. Of the several polymers synthesized, only the imprinted polymer formed with binary complex of Pb2+–DHCB showed quantitative enrichment of lead ion from aqueous solution. The relative standard deviation of the ﬁve replicate determinations of Pb (II) was3.26%. The detection limit for 150 mL of sample was 1.6 µg L-1 using ﬂame atomic absorption spectrometry. The developed method was successfully applied to the determination of trace lead in environmental samples with satisfactory results.
Modified Hydroxyl Value Assay and Application in Analysis of Molecular Ingredient of Polylactic Acid Oligomers
Authors: Qiu Zhi Ping , Chen Ji Da , Bu Juan , Shu Rong De
Published: August 2011

A modification was proposed to overcome problems of inaccuracy while traditional end group analysis was applied for hydroxyl value assay of polylactic acid oligomer owing to hydrolyzation. The modified method possessed simplification and accuracy resulting from avoiding hydrolyzation of polylactic acid oligomers, and it could be used for characterising molecular ingredient of polylactic acid oligomers, while the other techniques, such as 1H-NMR, Fourier transform infrared spectroscopy and viscosimetry, were applied at the same time.
Synthesis of a New Ion Imprinted Polymer Material for Separation and Preconcentration of Traces of Neodymium Ions
Authors: Liu Qing Peng , Li Hui Zhi , Zhuang Hai Yan , Pei Mei Shan
Published: August 2011

Neodymium ion imprinted polymers (IIP) were synthesized by formation of ternary complexes of neodymium ion with Vanillin Benzidine(VLB) and 4-vinylpyridine (VP) as chelating agent following copolymerizing with styrene as func­tional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linking monomer using 2,2´-azobisisobutyronitrile as initiator. Control polymers（CPs） were prepared under identical conditions without the use of neodymium imprint ion. The synthesized polymers were characterized by IR spectroscopy and elemental analyzer techniques. Of the several polymers synthesized, only the imprinted polymer formed with ternary complex of Nd3+–VLB–VP(1:1:2 IIP) showed quantitative enrichment of neodymium ion from aqueous solution.
Preparation of Conducting Polypyrrole in Gelatin Solution
Authors: Ma Hui Rong , Li Mei , Qiao Cong De , Yao Jin Shui
Published: August 2011

Polypyrrole (PPy) nanoparticles were successfully synthesized from the gelatin solution. PPy nanoparticles with different size and morphology are prepared by changing the preparation conditions including the gelatin concentrations, with surfactant or not. The characteristics of the obtained PPy particles was collected by scanning electron microscopy (SEM), The X-ray diffraction(XRD), Fourier transformation infrared(FT-IR) spectra and Four-probe conductivity meter. The results indicated PPy could form nanoparticles, whereas some bigger spheres occurred when the gelatin concentration is 0.05g/L and the conductivity of the PPy is 0.05S/cm. The possible mechanism was proposed that the gelatin is used as a morphology-directing agent in the polymerization process.
Synthesis of Chemical Responsive Chitosan–Grafted-Polyaniline Bio-Composite
Authors: Shukla S. K. , Tiwari Ashutosh
Published: August 2011

A polysaccharide based bioplolymer, chitosan was grafted with polyaniline through a simple room temperature oxidative-radical copolymerization method employing CuSO4 as a polymerizing agent. The grafting conditions were optimized by varying different parameters. The optimized experimental findings have been discussed and proposed a probable mechanism for the graft copolymerization. The representative sample of chitosan-graft-polyaniline (CHIT-g-PANI) was characterized using UV-vis, FTIR, X-ray diffraction and Scanning electron microscopy techniques taking chitosan as reference material. The result revealed the formation of grafted composite. Which exhibited highly improved electrical conductivity , in the order of ~ 10 -6 times due to the grafting of PANI onto chitosan backbone. Further , composite was found responsive in nature for H+ ion , which will be a suitable properties for its use in fabrication of bio-sensor.
The Effect of Different Optical Fibers on the Tensile Property of CFRPs
Authors: Tian Heng , Wang Ji Hui , Ji Yun Dong , Hao Xu Feng , Yin Yan Zi , Sun Jiu Xiao
Published: August 2011

This paper mainly investigates the effect of embedded optical fibers on the tensile prosperities of carbon fiber reinforced polymer-matrix composites (CFRPs). Different optical fibers are considered. The results show all the specimens are declining. And Optical Fiber (OF) with 245μm exhibit about 23.5% reduction.
Research on Hydration of Waterproof-Typed Semi-Hydrated Gypsum
Authors: Li Jian Quan , Gong Ming Zhu , Li Guo Zhong
Published: August 2011

The influences of saline waterproof agent composed of carboxylic acid sodium (RCOONa), Al2(SO4)3,K2SO4 on the hydration of semi-hydrated gypsum were investigated. The results showed: (1) with the concentration of K2SO4 increasing, the ζ potential rose due to the increasing K+ entering the electric double layer of gypsum; (2) with the concentration of Al2(SO4)3 heightening, the ζ potential gradually decreased as a result of the formed AFt phase during the hydration process and the increasing Al3+ entering the electric double layer of gypsum. The ζ potential rose because the RCOO-base groups adhered to the surface of gypsum crystal, which slowed down the growth rate of the gypsum crystal in direction c, and short hexahedron poles were produced.
Isothermal Oxidation Behavior of the AISI430 Stainless Steel at High Temperature in Static Air
Authors: Sun Bin , Wang Shou Ren , Wang Yan Jun , Pan Yong Zhi
Published: August 2011

Isothermal oxidation behavior of the AISI430 stainless steel was investigated at 900°C and 950°C in air. Isothermal themogravimettric analyses were performed at high-temperature for 360ks (kilo-seconds). The microstructures of the oxide films on the stainless steel were characterized by SEM and chemical analyses were performed by EDS and X-ray diffraction. The oxide film included outer layer and inner one. The outer layer was magnetite and hematite oxides with no significant amounts of chromium and the inner one was formed by iron and chromium spinel. Significantly accelerated and anomalous oxidation was observed with the stainless steel AISI430 in air at 900°C.
Study on Stress and Deformation of an Elevator Safety Gear Brake Block Using Experimental and FEA Methods
Authors: Kayaoglu Eren , Salman Ozlem , Candas Adem
Published: August 2011

It has been seen that Cylindrical Type Instantaneous Safety Gear, which is one of the most important element of an elevator system, during safety gear operation is being exposed to high stresses and brake accelerations. The stress and deformation distribution of a cylindrical type safety gear’s brake block was investigated using finite elements and experimental methods. Results found with FEM by using ABAQUS/CAE software were compared to experimental results. It is clearly seen that the element type and boundary conditions used in finite element modelling give satisfactory results.
Methionine as Corrosion Inhibitor of Brass in O2-Free 1M NaOH Solution
Authors: Wu Jin Fang , Wang Qing , Zhang Steng Tao , Yin Lin Liang
Published: August 2011

Methionine (MET) as a corrosion inhibitor for brass in O2-free 1M NaOH solution was investigated using weight loss, polarization curves, electrochemical impedance spectroscopy(EIS). The surface morphology after corrosion test was observed by scanning electron microscopy (SEM). Results indicate that MET is a cathodic inhibitor, and the inhibition efficiency increases with MET concentration.
Study on Properties of Ceramic-Lined Steel Pipes Prepared by Centrifugal Self-Propagating High-Temperature Synthesis
Authors: Zhu Yu , Huang Feng , Sun Shu Gang , Ni Hong Jun
Published: August 2011

Ceramic-lined steel pipes were made by adding nano-SiO2, Na2B4O7 additives into (Al-Fe2O3) combustion system on the basic of using centrifugal-SHS. The effect of nano-SiO2 on the density and corrosion-resistance of ceramic-lined steel pipes were studied with the condition of adding 4% Na2B4O7. The density was tested by Archimedes principle and the corrosion resistance was tested by weight-loss method. It is shown that the best density of composite steel pipes is got by adding 6% nano-SiO2 and the best corrosion-resistance is got by adding 4% nano-SiO2.
Synthesis and Properties of Waterborne UV Polyurethane
Authors: Zhou Xin Qi , Cao You Ming , Tian Jun Ling
Published: August 2011

Toluene diisocyanate(TDI), polyethylene glycol(PEG), double-propionic acid(DMPA), hydroxyethyl methacrylate(HEMA) and other raw materials were used to synthesis UV-curable waterborne polyurethane, and the effect of the synthesis condition on the particle size of the emulsion was investigated in this paper. The structure of the polyurethane was identified by infrared spectroscopy (IR), thermal decomposition properties was measured through the thermogravimetric(TG). The results showed that, the target product is expected waterborne UV polyurethane by IR. With DMPA content increasing, the particle size decrease, stability and appearance of the emulsion turn better. With the mole ration of PEG/DMPA decreasing, adhesion and water absorption of the film increase. TG analysis indicates that the thermal decomposition performance of the Waterborne UV Polyurethane （WPUA） is excellent.
Effects of Vibration Force Field on Extensional Stress of Polymer Melt in Contraction Die
Authors: Fan Ji Chang , Peng Xiang Fang
Published: August 2011

Electromagnetic dynamic plasticating extrusion, as one of main novel forming methods, has many important benefits to the forming process and the properties of its products. Here a visualization technique of flow induced birefringence was used to study the effects of the vibration parameters of screw on the extensional stress in contraction die. It is shown that , the extensional stress vibrate with the screw vibration at the same frequency; the amplitude of the extensional stress increases with the amplitude of the screw increasing; the average extensional stress at dynamic extrusion is less than that without vibration force, and it decreases with the screw vibration frequency or amplitude increasing.
Milling Force Predicting Modeling and Analysis for Helical Tooth End Mill on Inside Corner
Authors: Ji Yu Hua , Xiao Tong , Zhou Jian Qiang
Published: August 2011

Milling force is an important parameter during machining, which is directly related to the tool deformation, the tool life, the quality of the part surface, cutting heat, etc. In actual production, the cutting force on inside corner is more complex than the linear. For lack of the accurate cutting force information, there is liable to cause over-cut and owes-cut, rough surface, cutter breaking phenomenon. According to the structural characteristics of the corner, the cutting force model is established, which cutting force is further subdivided and the overall prediction accuracy is improved. Effects of different helix angle and forward amount each gear on cutting force. A good agreement is shown between the model simulation and the results of the experimental ones. The research provides a theoretical basis of predicting the cutting force on inside corner, and it is also helpful for further and practice.
Electro-Oxidation of Ethanol on the Preparation of Electroless Ni-P Alloy Electrode
Authors: Xie Shu Guang , Pan Zhan Chang , Hu Guang Hui , Wei Zhi Gang , Xiao Chu Min , Cheng Zhen Jun , Zeng Hai Xia , Tian Xin Long
Published: August 2011

Ni-P alloy electrode was prepared by electroless plating on the Cu-Zn substrate. The surface morphology and textural properties of electrode were characterized by Scanning electron microscope(SEM), Energy dispersive spectroscopy(EDS) and X-ray diffraction(XRD). The performance of Ni-P alloy electrode was tested by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy.The results of cyclic voltammetry showed that: At room temperature, Ni-P alloy electrode had significant catalytic effect on the electrocatalytic oxidation of ethanol in alkaline solution. Results of chronoamperometry and electrochemical impedance spectroscopy further confirmed the catalytic effect of Ni-P alloy electrode on the electrochemical oxidation of ethanol.
Research of Wheat Precision Seeding Test System Based on Image Processing
Authors: Lin Hai Bo , Dong Shu Liang , Qiu Yan , Yi Chui Jie
Published: August 2011

Wheat precision seeding test system is designed to develop a measurement device of wheat precision seeding with high efficiency and precision. The wheat seeds are falling from the seed sowing device to the conveyer belt. Using image processing techniques, the system gets the pictures of seeds on the belt. Then these pictures are processed and analyzed to calculate the qualified rate, reseeding rate and leakage sowing rate, etc. This paper introduces the whole structure, design parameters of the system, the hardware and software of the image acquisition system. Through selection of a proper threshold, the method of seed identification and seed-space measurement are given in this paper.