Elemental analysis of topaz from northern areas of Pakistan and assessment of induced radioactivity level after neutron irradiation for color induction

2010 ◽  
Vol 287 (3) ◽  
pp. 821-826 ◽  
Author(s):  
M. Wasim ◽  
W. A. Zafar ◽  
M. Tufail ◽  
M. Arif ◽  
M. Daud ◽  
...  
Author(s):  
Robert C. Rau ◽  
Robert L. Ladd

Recent studies have shown the presence of voids in several face-centered cubic metals after neutron irradiation at elevated temperatures. These voids were found when the irradiation temperature was above 0.3 Tm where Tm is the absolute melting point, and were ascribed to the agglomeration of lattice vacancies resulting from fast neutron generated displacement cascades. The present paper reports the existence of similar voids in the body-centered cubic metals tungsten and molybdenum.


Author(s):  
R. F. Egerton

An important parameter governing the sensitivity and accuracy of elemental analysis by electron energy-loss spectroscopy (EELS) or by X-ray emission spectroscopy is the signal/noise ratio of the characteristic signal.


Author(s):  
B. J. Panessa-Warren ◽  
J. B. Warren ◽  
H. W. Kraner

Our previous studies have demonstrated that abnormally high amounts of calcium (Ca) and zinc (Zn) can be accumulated in human retina-choroid under pathological conditions and that barium (Ba), which was not detected in the eyes of healthy individuals, is deposited in the retina pigment epithelium (RPE), and to a lesser extent in the sensory retina and iris. In an attempt to understand how these cations can be accumulated in the vertebrate eye, a morphological and microanalytical study of the uptake and loss of specific cations (K, Ca,Ba,Zn) was undertaken with incubated Rana catesbiana isolated retina and RPE preparations. Large frogs (650-800 gms) were dark adapted, guillotined and their eyes enucleated in deep ruby light. The eyes were hemisected behind the ora serrata and the anterior portion of the eye removed. The eyecup was bisected along the plane of the optic disc and the two segments of retina peeled away from the RPE and incubated.


Author(s):  
M. Shlepr ◽  
C. M. Vicroy

The microelectronics industry is heavily tasked with minimizing contaminates at all steps of the manufacturing process. Particles are generated by physical and/or chemical fragmentation from a mothersource. The tools and macrovolumes of chemicals used for processing, the environment surrounding the process, and the circuits themselves are all potential particle sources. A first step in eliminating these contaminants is to identify their source. Elemental analysis of the particles often proves useful toward this goal, and energy dispersive spectroscopy (EDS) is a commonly used technique. However, the large variety of source materials and process induced changes in the particles often make it difficult to discern if the particles are from a common source.Ordination is commonly used in ecology to understand community relationships. This technique usespair-wise measures of similarity. Separation of the data set is based on discrimination functions. Theend product is a spatial representation of the data with the distance between points equaling the degree of dissimilarity.


Author(s):  
S. A. Livesey ◽  
A. A. del Campo ◽  
E. S. Griffey ◽  
D. Ohlmer ◽  
T. Schifani ◽  
...  

The aim of this study is to compare methods of sample preparation for elemental analysis. The model system which is used is the human erythrocyte. Energy dispersive spectroscopic analysis has been previously reported for cryofixed and cryosectioned erythrocytes. Such work represents the reference point for this study. The use of plastic embedded samples for elemental analysis has also been documented. The work which is presented here is based on human erythrocytes which have been either chemically fixed and embedded or cryofixed and subsequently processed by a variety of techniques which culminated in plastic embedded samples.Heparinized and washed erythrocytes were prepared by the following methods for this study :(1). Chemical fixation in 4% paraformaldehyde/0.25% glutaraldehyde/0.2 M sucrose in 0.1 M Na cacodylate, pH 7.3 for 30 min, followed by ethanol dehydration, infiltration and embedding in Lowicryl K4M at -20° C.


2019 ◽  
pp. 27-33
Author(s):  
Aleksei K. Solovyov ◽  
Bi Guofu

The term “window” in architecture usually stands for an opening in a wall or roof for penetration of natural light, sunrays and fresh air in premises. Recently, the requirement of contact with environment is added to this condition. It is especially relevant for residential buildings where rooms are considered residential if they have windows. The energy consumption of a building depends on sizes, form and location of windows. In winter, windows cause huge heat losses, in summer, on the other hand, large heat enters a building via the windows and is required to be removed by means of air conditioning. Moreover, windows are used for penetration of natural light in premises, which assists in saving of large amounts of power for artificial illumination. This article discusses partial solving the problem of the energy efficiency of residential buildings by determining the most efficient area of windows in terms of energy spending for compensation of heat losses via windows in winter, elimination of heat penetration through them in summer and energy losses for artificial lighting throughout the year. The analysis of the results of calculation of power consumption for residential premises in conditions of monsoon climate of the Russian Far East and Northern areas of China (PRC) is provided.


2010 ◽  
Vol 130 (10) ◽  
pp. 955-962 ◽  
Author(s):  
Kaori Shigeta ◽  
Yoichi Nagata ◽  
Takahiro Iwai ◽  
Hidekazu Miyahara ◽  
Akitoshi Okino

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