Applications of SEM/EDXA in cement clinker investigation

1990 ◽  
Vol 48 (4) ◽  
pp. 870-871
Author(s):  
Arezki Tagnit-Hamou ◽  
Shondeep L. Sarkar
Keyword(s):  
Mineralogical Composition ◽  
Physicochemical Characteristics ◽  
Cement Clinker ◽  
Accurate Information ◽  
Phase Identification ◽  
History Of ◽  
Bulk Chemical ◽  
Resolution Imaging ◽  
Proven Method ◽  
Instantaneous Chemical

All the desired properties of cement primarily depend on the physicochemical characteristics of clinker from which the cement is produced. The mineralogical composition of the clinker forms the most important parameter influencing these properties.Optical microscopy provides reasonably accurate information pertaining to the thermal history of the clinker, while XRDA still remains the proven method of phase identification, and bulk chemical composition of the clinker can be readily obtained from XRFA. Nevertheless, all these microanalytical techniques are somewhat limited in their applications, and SEM/EDXA combination fills this gap uniquely by virtue of its high resolution imaging capability and possibility of instantaneous chemical analysis of individual phases.Inhomogeneities and impurities in the raw meal, influence of kiln conditions such as sintering and cooling rate being directly related to the microstructure can be effectively determined by SEM/EDXA. In addition, several physical characteristics of cement, such as rhcology, grindability and hydraulicity also depend on the clinker microstructure.

The Effect on Cement Mortar and Concrete by Admixture of Spray Drying Absorption Products

1989 ◽  
Vol 178 ◽  
Author(s):  
Kirsten G. Jeppesen
Keyword(s):  
Grain Size ◽  
Fly Ash ◽  
Cement Mortar ◽  
Setting Time ◽  
Mineralogical Composition ◽  
Cement Clinker ◽  
Strength Development ◽  
Fall Meeting ◽  
Freeze Thaw ◽  
Spray Dried

AbstractSpray dried absorption products (SDA) having special characteristics are used as substitutes for cement in the preparation of mortars; the qualities of the resulting mixed mortars are described. Conditions are described for mortar mixes, data for which were presented at the MRS Fall Meeting 1987.The influence of the composition of the SDA on water requirement and setting time has been studied. A full scale project involving 3 precast, reinforced concrete front-elements containing 20 and 30 wt.% SDA is described. Strength development, mineralogical composition and corrosion were monitored for two years.A non-standard freeze-thaw experiment was performed which compares mortars containing SDA and fly ash (FA) and also shows the effect of superplasticizer.The possibility of improving the SDA by grinding has been tested and a limited improvement has been found. The strength of the mixed mortars seems slightly influenced by the grain size of SDAGypsum (CaSO4·2H2O), synthetic calcium-sulphite (CaSO3·½H2O) and 2 SDAs have been used as retarders for cement clinker. Mortar test prisms have been cast and comparative strengths after curing for 3 years are reported

Studies in Contemporary Arabic Literature

1928 ◽  
Vol 4 (4) ◽  
pp. 745-759
Author(s):  
H. A. K. Gibb
Keyword(s):  
Economic History ◽  
Arabic Literature ◽  
Accurate Information ◽  
History Of

For some time past the writer has been endeavouring to collect material for the writing of an Economic History of Persia from the earliest times to the present. He has found himself greatly handicapped by the lack of accurate information respecting the earlier epochs of Persian history, and his researches in this direction are by no means complete.

SEM-based mineralogical mapping at the submicrometer-scale of modern Sardinian stromatolites

2021 ◽  
Author(s):  
Juliette Debrie ◽  
Dimitri Prêt ◽  
Karim Benzerara ◽  
Jean Paul Saint Martin
Keyword(s):  
Mineralogical Composition ◽  
Treatment Method ◽  
Heterogeneous Distribution ◽  
X Ray ◽  
Mineral Phases ◽  
Saint Martin ◽  
History Of ◽  
Phase Recognition ◽  
Mineral Mixtures ◽  
Insight Into

<p>Stromatolites, i.e. macroscopically laminated carbonate rocks formed by diverse microbial communities, are particularly emblematic geobiological materials since they are the oldest evidence of life-mineral interactions, dated up to 3.5 Gyrs ago.  They are found throughout the history of the Earth and have received strong attention because they provide precious information about microbial paleobiodiversity and paleoenvironments. However, while this information is interpreted based on our knowledge about modern analogs, the latter remains very incomplete. Here, we studied recently discovered modern stromatolites from Mari Ermi<sup>1</sup>, a coastal pond in Western Sardinia, that seasonally experience severe evaporation and broad salinity variations. For this purpose, we explored the mineralogical composition of these unique sedimentary archives and its spatial variations in order to gain better insight into how mineral phases record the conditions and processes of their formation. We investigated the heterogeneous distribution of minerals using quantitative X-ray chemical maps provided by energy dispersive x-ray spectrometry analyses coupled with scanning electron microscopy (SEM-EDXS). Hyperspectral maps were analyzed using an innovative data treatment method <sup>2</sup> allowing phase recognition within the complex mineral mixtures and solid solutions encountered. This method provided quantitative data on spatial distribution, modal content and associated calculated unit formulas for each identified mineral and phase with a hundred nanometer resolution. Based on these results, we will discuss the origin of the laminations in the stromatolites.</p><p>Reference:</p><p>1. Saint Martin, J.-P. & Saint Martin, S. Geo-Eco-Marina <strong>21</strong>, 35–53 (2015a).</p><p>2. Prêt, D. et al. American Mineralogist <strong>95</strong>, 1379–1388 (2010).</p>

scholarly journals WHAT THE BRICKS TELL US FROM A TEMPLE AT BURKHAN KHALDUN MOUNTAINS: CHRONOLOGICAL INSIGHTS FROM pIRIR LUMINESCENCE

2017 ◽  
pp. 4-12
Author(s):  
Saran S ◽  
Tengis S ◽  
Tsogtbaatar B
Keyword(s):  
Mineralogical Composition ◽  
World Heritage Site ◽  
Sacred Landscape ◽  
Great Opportunity ◽  
Fine Grain ◽  
Infrared Luminescence ◽  
Heritage Site ◽  
Unesco World Heritage Site ◽  
Time Period ◽  
History Of

The Burkhan Khaldun Mountains (Mongolia) and its surrounding sacred landscape are associated with Genghis Khan’s birth and burial place as described in “The Secret History of the Mongols”. It was listed as a UNESCO World Heritage Site on 4 July 2015 under the title «Great Burkhan Khaldun Mountain and its surrounding sacred landscape.”This study offered a great opportunity to apply the recently developed post-IR infrared luminescence (pIRIR) approach to feldspar using coarse and polymineral fine grain techniques and determine the manufacturing date of a brick sample associated with the ruins of the Buddhist temple at the Burkhan Khaldun Mountains. Furthermore, the mineralogical composition of different blue-grey colored bricks from various temple buildings such as the Buddhist temples in Karakorum, Dugan in Erdene Zuu and Avargyn Balgas were studied. The original place and date of manufacturing of the bricks was revealed using the pIRIR180 and pIRIR240 from coarse and fine grains from a heated feldspar sample and were 1280±40 AD and 1230±50 AD, correspondingly, which falls into the time period of extensive constructions in Karakorum.

scholarly journals Hydatid Cyst of Breast: A Case Report

2015 ◽  
Vol 12 (1) ◽  
pp. 41-42
Author(s):  
F Alam ◽  
RG Goel
Keyword(s):  
Case Report ◽  
Hydatid Cyst ◽  
Hydatid Disease ◽  
Needle Aspiration ◽  
Accurate Information ◽  
Endemic Region ◽  
Medical College ◽  
Control And Prevention ◽  
History Of ◽  
Needle Aspiration Cytology

Hydatid cyst is a zoonotic disease which occurs due to infectivity with larval stage of Echinococcus granulosus. The disease is chronic and cysts can be lodged in different organs. It has cosmopolitan distribution and impact health and economical challenges for many countries throughout the world. The location of the disease is mostly in the liver and lungs. Hydatid disease of breast is extremely rare. A case report of 24 year female with the diagnosis of the hydatid breast is described in detail. The patient presented with painless lump in the upper inner quadrant of right breast of two months duration. History of trauma, pus discharge, itching, weight loss, fever or hormonal therapy were absent. The patient was diagnosed preoperatively as cysticercosis right breast by fine needle aspiration cytology based on the laboratory results conducted outside the hospital. However, histopathology confirmed the diagnosis of hydatid breast. It is the second diagnosed case in Nepal. Therefore, accurate information on the distribution of the disease is first step for the control and prevention. Only few reports are published in the literature about breast hydatid cyst.Thus, we want to emphasize the importance of keeping hydatid disease in differential diagnosis of cystic breast lesions, particularly in endemic region, where the disease could mimic fibroadenoma, phyllodes tumors, chronic abscesses.Journal of Nepalgunj Medical College Vol.12(1) 2014: 41-42

scholarly journals 50th Anniversary Celebrations of Atomic-Resolution Imaging

2005 ◽  
Vol 13 (6) ◽  
pp. 46-47
Author(s):  
Thomas F. Kelly ◽  
Allan J. Melmed
Keyword(s):  
50Th Anniversary ◽  
Atomic Resolution ◽  
State University ◽  
Pennsylvania State University ◽  
Field Ion Microscopy ◽  
The World ◽  
Penn State ◽  
History Of ◽  
Resolution Imaging ◽  
Ion Microscopy

October 2005 marks 50 years since the first images achieving atomic resolution were obtained by Erwin Miiller and Kanwar Bahadur at the Pennsylvania State University using field ion microscopy. An image from that seminal work is shown in Figure 1. Two separate meetings were held this year to commemorate this important event in the history of microscopy; the 50th Anniversary of Atomic Resolution Microscopy, held June 15-17, 2005 at Penn State and the Golden Anniversary of Atomic Resolution Imaging, a symposium at Microscopy and Microanalysis 2005 in Honolulu held July 31 to August 4, 2005. These celebrations were timed to coincide also with the World Year of Physics 2005 http://www. wyp2005.org/.

Discussing the dating of ferruginous duricrusts: promises from mineralogy of supergene minerals with non-destructive microsampling

2020 ◽  
Author(s):  
Karina Marques ◽  
Thierry Allard ◽  
Guillaume Morin ◽  
Benoît Baptiste ◽  
Cécile Gautheron ◽  
...  
Keyword(s):  
Mineralogical Composition ◽  
Alluvial Fan ◽  
Secondary Minerals ◽  
Origin And Evolution ◽  
Late Neogene ◽  
Erosion History ◽  
Powder Samples ◽  
History Of ◽  
Different Populations ◽  
Fine Resolution

<p>Ferruginous duricrusts record a part of the Earth’s geodynamical and climatic history in tropical area, because they can be formed over a wide geologic period. However, the events and processes related to their formation, transformation and distribution are still obscure. This is mainly due to the complexity arising from their finely divided and polycrystalline nature together with the coexistence of various generations of supergene minerals, such as iron and aluminum oxides, oxyhydroxides or hydroxides (e.g. goethite, hematite and gibbsite) and kaolinite, even at microscopic scale. Classical mineralogical investigations are often realized using powders samples, which hinders subsequent analyses on the same sample, such as SEM or (U-Th)/He dating. Thus, the aim of this study was to propose a new way to investigate the mineralogy of supergene ferruginous samples on micrometric grains that will be analyzed by (U-Th)/He dating method. Prior to this analysis, we first compare the X-ray diffraction data of grains and small amounts of powders looking to reveal the mineralogical composition of populations of secondary minerals of a ferruginous duricrust by taking into account the heterogeneity of the material. Samples were collected from a ferruginous duricrust with pisolitic structure developed over epiclastic conglomerates and sandstones deposited by alluvial fan and fluvial streams from the Upper Cretaceous at the western Minas Gerais state (Brazil). The geomorphology of the study area is delineated by remnants of paleosurface (up to 1,000 m a.s.l.), which comprises an important record of long-term Brazilian continental history.Macroscopic facies recognized on duricrusts sections were described, which allowed the identification of various populations of secondary minerals. After this detailed description, grains (size < 0.5 mm) were collected and powder samples of each population were prepared by crushing. Overall, the results point out that the grain and powder samples could be used to identify mineralogical composition at fine resolution of secondary minerals from ferruginous duricrusts. In addition, XRD results are similar for both types of sample preparation, however the < 0.5 mm grain samples are more advantageous because they are not destructive and thus allow to get a finer description of the mineralogy of different populations and can subsequently be used for e.g. (U-Th)/He dating, providing critical information for interpreting and discussing the ages of iron oxides.</p><p><strong>Grant:</strong> 19/10708-7; 17/22292-4; 17/20788-2, São Paulo Research Foundation (FAPESP)</p><p><strong>References</strong></p><p>Allard, T., Gautheron, C., Riffel, S.B., Balan, E., Soares, B.F., Pinna-Jamme, R., Derycke, A., Morin G., Bueno, G.T., Nascimento, N., 2018. Combined dating of goethites and kaolinites from ferruginous duricrusts. Deciphering the Late Neogene erosion history of Central Amazonia. Chemical Geology 479, 136-150.</p><p>Monteiro, H.S., Vasconcelos, P.M.P., Farley, K.A., Spier, C.A., Mello, C.L., 2014. (U-Th)/He geochronology of goethite and the origin and evolution of cangas. Geochim. Cosmochim. Acta  131, 267–289.</p><p>Vasconcelos, P.M., Heim, J.A., Farley, K.A., Monteiro, H.S., Waltenberg, K., 2013. <sup>40</sup>Ar/<sup>39</sup>Ar and (U–Th)/He - <sup>4</sup>He/<sup>3</sup>He geochronology of landscape evolution and channel irondeposit genesis at LynnPeak, Western, Australia. Geochim. Cosmochim. Acta 117, 283-312.</p>

scholarly journals Intramedullary Spinal Capillary Hemangioma: Case Report

2015 ◽  
Vol 36 (02) ◽  
pp. 125-127
Author(s):  
Leonardo Welling ◽  
Mariana Welling ◽  
Eberval Figueiredo
Keyword(s):  
Spinal Cord ◽  
Complete Removal ◽  
Conus Medullaris ◽  
Capillary Hemangioma ◽  
The Body ◽  
Accurate Information ◽  
Histopathological Diagnosis ◽  
Intramedullary Lesion ◽  
History Of

AbstractCapillary hemangiomas involving the neuraxis are very uncommon. In the spinal cord, they are located mainly intradural and extramedullary. To our knowledge, only four cases in conus medullaris have been previously described. In our case, a 46-year-old man was admitted with back pain, sphincter disturbances, as well as progressive weakness and numbness on the lower extremities. Magnetic resonance imaging revealed an undefined intramedullary lesion on the conus medullaris. The patient underwent microsurgery, which achieved complete removal. Histopathological diagnosis was compatible with capillary hemangioma. His postoperative course was uneventful and all symptoms, including bladder dysfunction clearly regressed. The treatment of intramedullary capillary hemangiomas is very critical in preventing unnecessary morbidity, providing accurate information with respect to prognosis, and establishes a regular outpatient follow-up. The natural history of this lesion involving the spinal cord is not well described, although they are common elsewhere in the body.

Methods of Determining the Numbers of Bacteria in Milk

1930 ◽  
Vol 1 (2) ◽  
pp. 111-135 ◽  
Author(s):  
A. T. R. Mattick
Keyword(s):  
Previous History ◽  
Standard Technique ◽  
Point Of View ◽  
Plate Count ◽  
Accurate Information ◽  
Plate Method ◽  
Large Sphere ◽  
Keeping Quality ◽  
History Of ◽  
Bacterial Content

SummaryOne fact emerges from a consideration of the literature upon the methods at present in use for determining the bacteriological content of milk, viz. no one method is capable of giving exact information as to the numbers of living bacteria present.The plate count has been shown to be subject to a number of limitations to its accuracy, but it is possible that these are much more the result of failure to appreciate the importance and effect of observing the protocols of a standard technique, than of insurmountable causes of error inherent in the method. Any one laboratory should be able to return results which are comparable from sample to sample, but as has been shown, it is unlikely that results will agree between laboratory and laboratory unless the most rigid precautions to secure uniformity are enforced. This latter fact does not seem to be of very great importance, since the most that can be expected is that results shall reflect the condition of the milk at the time of examination. These will be governed by the previous history of the milk. Figures have been given which show (p. 120) that, if milk is properly produced and handled, the bacterial content will be, even 24 hours or more after milking, within the range where the plate count as a method of computation is more reliable than any other known method.From the point of view of keeping quality and value for some manufacturing purposes, milk is either good or bad, and the obvious inaccuracy of the plate or any other method is a matter of small importance when the bacterial content has once exceeded 500,000 per 1 c.c.Nevertheless there is no sort of justification for attempting to separate milk into classes, which are not broad enough to include the variations which have been repeatedly shown, although not always on sound lines, to occur in the figures. It may be possible so to separate milk of very low bacterial content, but it is not possible to do so when the bacterial content exceeds, say, 200,000 per 1 c.c. It must always be remembered that the colonies appearing on agar plates arise from groups as well as from individual bacteria.In view of the fact that keeping quality, the basis on which the consumer judges milk, depends upon the kinds as well as upon the numbers of bacteria, it appears wise to supplement bacterial examinations with determinations of keeping quality, and, in view of their special significance, of organisms of the coliform group.It seems that, although the methods of Breed and Frost are excellent for rapidly classifying milk into broad grades, their accuracy is necessarily diminished by their very nature, in that the results obtained are dependent upon computation to a greater extent than the plate method and, although it is possible to secure good results, the time consumed in getting these is as great, if not indeed greater, than by the plate method.The reductase test, although it has a large sphere of usefulness as a factory method, will not give accurate information as to the numbers of bacteria in milk.

scholarly journals Volodymyr Boshko: an attempt to make a scientific biography of a scholar

2019 ◽  
pp. 12-21
Author(s):  
Igor Usenko ◽  
Liudmyla Mikhnevych
Keyword(s):  
Family Law ◽  
Educational Activity ◽  
Accurate Information ◽  
Academic Institutions ◽  
Scientific Heritage ◽  
Legal Studies ◽  
General Terms ◽  
History Of ◽  
Academy Of Sciences ◽  
First Time

On the basis of the sources published and new archival materials, more accurate information on well-known jurist Volodymyr Boshko’s life and his scientific, teaching and public activities is provided. For the first time, information on the unlawful repression of the scientist’s daughter and older brother is given. The main stages of his life, career, and scientific heritage are described. The little known scientific works of the jurist have been returned to scientific circulation. Particular attention is paid to Boshko’s early social and political essays. His achievements in the spheres of history of law and family law have been identified. It is emphasized that professor Boshko was the author of the first Soviet textbook on history of political and legal studies, which had been the only one for 30 years. It also has been found out that his scientific works concerning problems of the legal status of spouses and illegitimate children, alimony law and factual marriage are still relevant. The legal positions of the scholar on issues of state law, in particular the notions of sovereignty, equality of states, sovereignty of federations, content and legal nature of some human rights, are also covered. The works of the professor in the fields of civil and agrarian law are also mentioned. His talent as a teacher and the head of a number of academic institutions is indicated, in particular the attention is paid to his educational activity in various academic institutions of railway transport. The information on Boshko’s initiative on the state program “Big Dnieper” is given. The jurist’s affiliation to the activities of Kyiv Branch of the All-Ukrainian Scientific Association of Oriental Studies and of the All-Ukrainian Academy of Sciences has been revealed. For the first time, the scholar’s initiative to establish the Institute of Law and the Department of Philosophy of Law in the system of the Academy of Sciences of the USSR is covered in detail. The milestones of the scientist’s life in the evacuation and post-war years of his activity at the Law Faculty of Kyiv University are reproduced in general terms. It is found that in recent years, the scholar had been actively working on his doctoral thesis on Soviet family law and had been preparing a three-volume work in history of political and legal studies, but these works were not completed.

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