Different physical, mechanical and chemical processes, such as： ion implantation, oxidation, nitridation and others create on the surface of materials residual stress state, characterized by high level and strong gra...Different physical, mechanical and chemical processes, such as： ion implantation, oxidation, nitridation and others create on the surface of materials residual stress state, characterized by high level and strong gradient. X-ray diffraction method widely used for stress measurements has some difficulties in interpretation of experimental data, when the depth of X-ray penetration is compared with thickness of surface layer where inhomogeneous stress distribution is localized. Early it has been shown by authors that diffraction line broadening occurs when analyzed surface is characterized by strong gradient. The interest to study the diffraction line broadening is connected to the possibility of obtaining information about parameters of surface stress distribution. In the present paper the convolution and deconvolution concepts of Fourier analysis were applied to study X ray diffraction line broadening caused by surface stress gradients. Developed methodology allows determining of stress distribution in superficial layers of materials.展开更多
The density,nature of the dislocations and distribution of the domain sizes in cold-deformed Pb-Ca-Sn solid solution were determined by X-ray diffraction profile analysis.The dislocation densities are of the order of ...The density,nature of the dislocations and distribution of the domain sizes in cold-deformed Pb-Ca-Sn solid solution were determined by X-ray diffraction profile analysis.The dislocation densities are of the order of 1010 cm-2.The strain broadening of diffraction profiles was accounted for by dislocation contrast factor.The coherent domain size was determined by the recently developed PM2K software package.Assuming that the domain size distribution is log-normal,the distribution function（median μ and variance σ） was calculated from the size parameters determined from X-ray diffraction profile analysis.展开更多
用磁控溅射法将 NiTi 薄膜沉积在纯 Cu 箔片上,在 800℃分别固溶 30 min,45 min,60 min 和 120 min;采用X 射线傅氏线形分析法计算各固溶时间的位错密度及位错分布参量。随固溶时间的增加,平均位错密度不断下降; 亚晶粒尺寸 D 逐渐增加;...用磁控溅射法将 NiTi 薄膜沉积在纯 Cu 箔片上,在 800℃分别固溶 30 min,45 min,60 min 和 120 min;采用X 射线傅氏线形分析法计算各固溶时间的位错密度及位错分布参量。随固溶时间的增加,平均位错密度不断下降; 亚晶粒尺寸 D 逐渐增加; 平均位错分布参量基本不变。由位错密度及位错分布参量计算得到 NiTi 薄膜材料的显微硬度值,随固溶时间的增加,显微硬度计算值明显低于测量值。展开更多
To evaluate the efficiency of modified epoxy resins using bisphenol-A, hydantoin & cyanuric acid & to investigate the structural change due to the presence of Nitrogen atoms in polymeric chain for improved ins...To evaluate the efficiency of modified epoxy resins using bisphenol-A, hydantoin & cyanuric acid & to investigate the structural change due to the presence of Nitrogen atoms in polymeric chain for improved insulating properties, weatherability etc. The samples of epoxy resin bisphenol-a, hydantoin and Cyanuric acid based was taken for X-RAY diffraction analysis. The diffraction patterns were Fourier analysed to get an exact idea about the change in the polymer structure. From X-RAY diffraction analysis it was found that all physical parameters like area of cross section, number of carbon atoms per entanglement, stiffness parameter, particle size, percentage crystallinity & electron density fluctuation, in case of bisphenol-A based epoxy resin is more than other epoxy resins;that is;as the number of nitrogen atoms increased, all the physical parameters were reducedIn the present study only X-ray diffraction patterns of bisphenol-A, hydantoin and cyanuric acid based epoxy resins were studied. However their dielectric and ultrasonic properties could also be studied to get more information about the structur With the help of X-RAY diffraction patterns, one can easily check the synthesized samples of epoxy resins. The method to investigate the structural analysis of epoxy resin was novel and could find numerous applications in surfacecoatings.展开更多
The surface of Thar coal has been characterized by spectroscopic, microscopic and chemical methods using atomic absorption spectroscopy, fourier transform infrared analysis, X-ray diffraction, scanned electron microsc...The surface of Thar coal has been characterized by spectroscopic, microscopic and chemical methods using atomic absorption spectroscopy, fourier transform infrared analysis, X-ray diffraction, scanned electron microscopy and pH titration. The samples contained high moisture, low volatile and low to moderate sulfur content and ranked as lignite (heating value 2541 - 4289 btu/lb on moist, mineral-matter-free basis). Scanned electron micrographs show porous matrix with calcium, potassium or sodium minerals. Fourier transform infrared analysis confirmed the presence of aluminum, silica and hydrate mineral constituents also. The spectra showed C=C aromatic groups at 1604 - 1609 cm-1. Phenolic ester and carboxylic acid are identified by C=O stretching vibration peaks at 1702 cm-1. The peaks of quartz and kaolinite were observed at 900 - 1100 cm-1. Point of zero charge of Thar coal has been estimated as 6.00 to 6.27 through adsorption of H+ and OH- ions by suspending coal particles in aqueous electrolyte solution. Oxygen containing functional groups, mineral matter, and metal oxides are found to have a remarkable impact on point of zero charge. The surface characterization study will be helpful in the separation of hydrophilic impurities during coal preparation processes considering pzc as the controlling展开更多
Sol-gel derived silica has tremendous applications as a biocompatible scaffold for the immobilization of cells. The use of xerogel as a matrix in the blueprint of biosensors is an appealing proposition due to several ...Sol-gel derived silica has tremendous applications as a biocompatible scaffold for the immobilization of cells. The use of xerogel as a matrix in the blueprint of biosensors is an appealing proposition due to several inimitable characteristics of xerogels, primarily because of their high porous nature, amendable pore size, and exceptionally large internal surface area. Morphological （X-Ray Diffraction and Thermogravimmetric Analysis） and optical （Fourier Transform Infrared and UV-Vis absorption） studies of the silica matrices with entrapped Rhizobial （Rz） structure of the biomaterial has been made. Temporal and concentration dependent studies were conducted for impregnated samples; it showed that the response time for the new biosensor for determining the concentration of Rz is less than 20 min. In this work, first time a novel avenue to create a generic approach for the fabrication of biosensor has been created.展开更多
文摘Different physical, mechanical and chemical processes, such as： ion implantation, oxidation, nitridation and others create on the surface of materials residual stress state, characterized by high level and strong gradient. X-ray diffraction method widely used for stress measurements has some difficulties in interpretation of experimental data, when the depth of X-ray penetration is compared with thickness of surface layer where inhomogeneous stress distribution is localized. Early it has been shown by authors that diffraction line broadening occurs when analyzed surface is characterized by strong gradient. The interest to study the diffraction line broadening is connected to the possibility of obtaining information about parameters of surface stress distribution. In the present paper the convolution and deconvolution concepts of Fourier analysis were applied to study X ray diffraction line broadening caused by surface stress gradients. Developed methodology allows determining of stress distribution in superficial layers of materials.
文摘The density,nature of the dislocations and distribution of the domain sizes in cold-deformed Pb-Ca-Sn solid solution were determined by X-ray diffraction profile analysis.The dislocation densities are of the order of 1010 cm-2.The strain broadening of diffraction profiles was accounted for by dislocation contrast factor.The coherent domain size was determined by the recently developed PM2K software package.Assuming that the domain size distribution is log-normal,the distribution function（median μ and variance σ） was calculated from the size parameters determined from X-ray diffraction profile analysis.
文摘用磁控溅射法将 NiTi 薄膜沉积在纯 Cu 箔片上,在 800℃分别固溶 30 min,45 min,60 min 和 120 min;采用X 射线傅氏线形分析法计算各固溶时间的位错密度及位错分布参量。随固溶时间的增加,平均位错密度不断下降; 亚晶粒尺寸 D 逐渐增加; 平均位错分布参量基本不变。由位错密度及位错分布参量计算得到 NiTi 薄膜材料的显微硬度值,随固溶时间的增加,显微硬度计算值明显低于测量值。
文摘To evaluate the efficiency of modified epoxy resins using bisphenol-A, hydantoin & cyanuric acid & to investigate the structural change due to the presence of Nitrogen atoms in polymeric chain for improved insulating properties, weatherability etc. The samples of epoxy resin bisphenol-a, hydantoin and Cyanuric acid based was taken for X-RAY diffraction analysis. The diffraction patterns were Fourier analysed to get an exact idea about the change in the polymer structure. From X-RAY diffraction analysis it was found that all physical parameters like area of cross section, number of carbon atoms per entanglement, stiffness parameter, particle size, percentage crystallinity & electron density fluctuation, in case of bisphenol-A based epoxy resin is more than other epoxy resins;that is;as the number of nitrogen atoms increased, all the physical parameters were reducedIn the present study only X-ray diffraction patterns of bisphenol-A, hydantoin and cyanuric acid based epoxy resins were studied. However their dielectric and ultrasonic properties could also be studied to get more information about the structur With the help of X-RAY diffraction patterns, one can easily check the synthesized samples of epoxy resins. The method to investigate the structural analysis of epoxy resin was novel and could find numerous applications in surfacecoatings.
文摘The surface of Thar coal has been characterized by spectroscopic, microscopic and chemical methods using atomic absorption spectroscopy, fourier transform infrared analysis, X-ray diffraction, scanned electron microscopy and pH titration. The samples contained high moisture, low volatile and low to moderate sulfur content and ranked as lignite (heating value 2541 - 4289 btu/lb on moist, mineral-matter-free basis). Scanned electron micrographs show porous matrix with calcium, potassium or sodium minerals. Fourier transform infrared analysis confirmed the presence of aluminum, silica and hydrate mineral constituents also. The spectra showed C=C aromatic groups at 1604 - 1609 cm-1. Phenolic ester and carboxylic acid are identified by C=O stretching vibration peaks at 1702 cm-1. The peaks of quartz and kaolinite were observed at 900 - 1100 cm-1. Point of zero charge of Thar coal has been estimated as 6.00 to 6.27 through adsorption of H+ and OH- ions by suspending coal particles in aqueous electrolyte solution. Oxygen containing functional groups, mineral matter, and metal oxides are found to have a remarkable impact on point of zero charge. The surface characterization study will be helpful in the separation of hydrophilic impurities during coal preparation processes considering pzc as the controlling
文摘Sol-gel derived silica has tremendous applications as a biocompatible scaffold for the immobilization of cells. The use of xerogel as a matrix in the blueprint of biosensors is an appealing proposition due to several inimitable characteristics of xerogels, primarily because of their high porous nature, amendable pore size, and exceptionally large internal surface area. Morphological （X-Ray Diffraction and Thermogravimmetric Analysis） and optical （Fourier Transform Infrared and UV-Vis absorption） studies of the silica matrices with entrapped Rhizobial （Rz） structure of the biomaterial has been made. Temporal and concentration dependent studies were conducted for impregnated samples; it showed that the response time for the new biosensor for determining the concentration of Rz is less than 20 min. In this work, first time a novel avenue to create a generic approach for the fabrication of biosensor has been created.
