Molecular Characterization of Diesel Fuels Using Modern Analytical Techniques

2020 ◽  
pp. 61-76
Author(s):  
C. S. Hsu ◽  
G. J. Dechert ◽  
D. J. Abbott ◽  
M. W. Genowitz ◽  
R. Barbour
2021 ◽  
Vol 11 (6) ◽  
pp. 51-53
Author(s):  
Kundan Patil

Calcium is one of the essential elements for living beings. As a supplement, it is used to treat Calcium deficiencies due to a calcium deficient diet. In Rasaratnasamuchchaya Calcium bhasma (Eggshell bhasma) is included as a rich calcium supplement. There is a need for work on the determination of the percentage of Calcium in the eggshell and its limit of acceptance. Easy absorption of bhasma in the body is possible when its preparation is carried out in an acidic medium. Lemon juice is one of the acidic mediums employed for this purpose at pH 2.4. The eggshell powder is subjected to five calcination cycles to convert it into the Bhasma. Analysis of Eggshell Bhasma has been done by various modern analytical techniques to determine its exact chemical compositions. Various instrumental methods like XRD, FTIR, and SEM have been incorporated for analysis of raw materials, intermediates as well as final products. The calcium carbonate present in eggshells is in calcite form. In the present work, structural and chemical characterization of eggshell bhasma was carried out to develop an analytical profile of it.


2007 ◽  
Vol 1 (3) ◽  
pp. 165-173
Author(s):  
Aneta Lorek ◽  
◽  
Maciej Paczuski ◽  

In this work, experimental methods used for the evaluation of stability of solids in liquids dispersions, are presented. For the characterization of dispersion components, modern analytical techniques, such as tensiometry, scanning and static turbidimetry, have been applied. The influence of selected surface active substances on the dispersion stability was demonstrated.


Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 448
Author(s):  
Andrey V. Karasev ◽  
Dmitry Gorkusha ◽  
Konstantin V. Grigorovich ◽  
Pär G. Jönsson

In this study, a complete and comprehensive analysis of non-metallic inclusions (NMI) in an Fe-10%Ni alloy was done by using two modern analytical methods that complement each other: Electrolytic Extraction (EE) of inclusions from metal samples followed by investigations by using Scanning Electron Microscopy (SEM) and Fractional Gas Analysis (FGA). The composition, morphology, size and number of different NMIs and clusters were investigated in metal samples taken after deoxidation by additions of Ti, Ti/Zr and Ti/Mg. The obtained results were discussed with respect to formation, modification and removal of NMIs and clusters depending on the type of deoxidations and the holding time. It was found that the peaks of oxygen reduced from different oxide inclusions obtained by the FGA measurements corresponded well to the main types of inclusions and clusters observed by using the EE + SEM method. More specifically, the total O content in oxide inclusions (ONMI) increases by 10% after a Zr addition and then decreases linearly by 40% during 5 min of holding due to flotation of NMIs and clusters. However, after a Mg addition in the melt deoxidized by Ti, the ONMI content decreases drastically by 63% during 5 min of holding, due to a fast floatation of NMIs caused by bubbles of vaporized Mg.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
Simon Thomas

Trends in the technology development of very large scale integrated circuits (VLSI) have been in the direction of higher density of components with smaller dimensions. The scaling down of device dimensions has been not only laterally but also in depth. Such efforts in miniaturization bring with them new developments in materials and processing. Successful implementation of these efforts is, to a large extent, dependent on the proper understanding of the material properties, process technologies and reliability issues, through adequate analytical studies. The analytical instrumentation technology has, fortunately, kept pace with the basic requirements of devices with lateral dimensions in the micron/ submicron range and depths of the order of nonometers. Often, newer analytical techniques have emerged or the more conventional techniques have been adapted to meet the more stringent requirements. As such, a variety of analytical techniques are available today to aid an analyst in the efforts of VLSI process evaluation. Generally such analytical efforts are divided into the characterization of materials, evaluation of processing steps and the analysis of failures.


Author(s):  
J. I. Bennetch

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.


Author(s):  
Julia T. Luck ◽  
C. W. Boggs ◽  
S. J. Pennycook

The use of cross-sectional Transmission Electron Microscopy (TEM) has become invaluable for the characterization of the near-surface regions of semiconductors following ion-implantation and/or transient thermal processing. A fast and reliable technique is required which produces a large thin region while preserving the original sample surface. New analytical techniques, particularly the direct imaging of dopant distributions, also require good thickness uniformity. Two methods of ion milling are commonly used, and are compared below. The older method involves milling with a single gun from each side in turn, whereas a newer method uses two guns to mill from both sides simultaneously.


2006 ◽  
Vol 175 (4S) ◽  
pp. 467-467
Author(s):  
Victor K. Lin ◽  
Shih-Ya Wang ◽  
Claus G. Roehrbom

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