Analytical data for some minor elements in arkosic sandstones of the Fountain Formation, Colorado

Crystal-liquid partition coefficients for pyroxene, spinels, and melilite, in slags

Mineralogical Magazine ◽

10.1180/minmag.1983.047.344.08 ◽

1983 ◽

Vol 47 (344) ◽

pp. 335-345 ◽

Cited By ~ 4

Author(s):

E. Wearing

Keyword(s):

Crystal Structure ◽

Electron Microprobe ◽

Partition Coefficients ◽

Microprobe Analysis ◽

Electron Microprobe Analysis ◽

Analytical Data ◽

Minor Element ◽

Minor Elements ◽

Metallurgical Slags

AbstractThe chemistry of spinels, plagioclase, and iron-rich, normally zoned pyroxene and melilite from some metallurgical slags has been investigated by electron microprobe analysis. Minor element partition coefficients, some of which are composition-dependent, have been calculated from the analytical data. The pyroxene/liquid partition coefficients range from 4.03 to 0.03 in the order Ti/Zr, Al, Mn, Zn, Ba, Sn, Na, reflecting increasing incompatibility. The spinel/liquid partition coefficients range from 40.89 to 0.02 but in the order Ti, Ni, Mg/Zn, Al, Mn, Cu, Sn, Zr. However, Sn becomes very compatible when the pyroxene and spinels crystallize in association with cassiterite. Melilite greatly discriminates against the incorporation of minor elements into its crystal structure. The crystallization of these phases produces residual liquids enriched in Na, Mn, Zn, Sn, Ba, W, and Pb.

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High Resolution Observations of Ion-Milling Induced Transformation in Synthetic Hollandses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097259 ◽

1981 ◽

Vol 39 ◽

pp. 114-115 ◽

Cited By ~ 1

Author(s):

T. J. Headley

Keyword(s):

High Resolution ◽

Radioactive Waste Disposal ◽

Ion Milling ◽

Minor Elements ◽

Waste Forms ◽

Carbon Substrates ◽

Structural Differences ◽

Oxide Phases ◽

Argon Ions ◽

High Resolution Microscopy

Oxide phases having the hollandite structure have been identified in multiphase ceramic waste forms being developed for radioactive waste disposal. High resolution studies of phases in the waste forms described in Ref. [2] were initiated to examine them for fine scale structural differences compared to natural mineral analogs. Two hollandites were studied: a (Ba,Cs,K)-titan-ate with minor elements in solution that is produced in the waste forms, and a synthesized BaAl2Ti6O16 phase containing ∼ 4.7 wt% Cs2O. Both materials were consolidated by hot pressing at temperatures above 1100°C. Samples for high resolution microscopy were prepared both by ion-milling (7kV argon ions) and by crushing and dispersing the fragments on holey carbon substrates. The high resolution studies were performed in a JEM 200CX/SEG operating at 200kV.

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HREM interface studies in SiC-whisker-reinforced Al2O3 and Si3N4 ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105734 ◽

1988 ◽

Vol 46 ◽

pp. 734-735

Author(s):

W. Braue ◽

R.W. Carpenter ◽

D.J. Smith

Keyword(s):

Analytical Data ◽

Base Material ◽

High Strength ◽

Ceramic Composites ◽

Good Thermal Stability ◽

All Ceramic ◽

Sic Whiskers ◽

Base Composite ◽

C 30 ◽

Si3n4 Ceramics

Whisker and fiber reinforcement has been established as an effective toughening concept for monolithic structural ceramics to overcome limited fracture toughness and brittleness. SiC whiskers in particular combine both high strength and elastic moduli with good thermal stability and are compatible with most oxide and nonoxide matrices. As the major toughening mechanisms - crack branching, deflection and bridging - in SiC whiskenreinforced Al2O3 and Si3N41 are critically dependent on interface properties, a detailed TEM investigation was conducted on whisker/matrix interfaces in these all-ceramic- composites.In this study we present HREM images obtained at 400 kV from β-SiC/α-Al2O3 and β-SiC/β-Si3N4 interfaces, as well as preliminary analytical data. The Al2O3- base composite was hotpressed at 1830 °C/60 MPa in vacuum and the Si3N4-base material at 1725 °C/30 MPa in argon atmosphere, respectively, adding a total of 6 vt.% (Y2O3 + Al2O3) to the latter to promote densification.

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Developing GIS portal to ensure sanitary and epidemiological surveillance of transferring radio engineering objects

Hygiene and Sanitation ◽

10.33029/0016-9900-2020-99-4-344-350 ◽

2020 ◽

Vol 99 (4) ◽

pp. 344-350

Author(s):

Evgeny V. Zibarev ◽

A. S. Afanasev ◽

O. V. Slusareva ◽

T. I. Muragimov ◽

V. A. Stepanets ◽

...

Keyword(s):

Electromagnetic Fields ◽

Analytical Data ◽

Base Stations ◽

Epidemiological Surveillance ◽

Graphical Form ◽

Residential Areas ◽

Information Portal ◽

Radiofrequency Electromagnetic Fields ◽

Online Mode ◽

Automated Processes

In recent years, in the Russian Federation there has been an increase in the levels of radiofrequency electromagnetic fields in residential areas, including due to an increase in the number of base stations (BS). The purpose of sanitary and epidemiological surveillance at the stages of placement and commissioning of base stations (BS) is to prevent their adverse effects on public health. The increase in the number of base stations, together with the advent of new electronic equipment and antennas, provide opportunities for improving the processes of their accounting at the stage of placement and monitoring of the levels of radiofrequency electromagnetic fields at the operation stage. This automation tool can be a geo-information portal for providing sanitary and epidemiological surveillance of cellular base stations. The prototype of the geo-information portal allows both calculating the size of sanitary protection zones (SPZ) and building restriction zones (RZ) from the BS in online mode, displaying the results of calculations in graphical form and issuing sanitary and epidemiological conclusions for the placement and operation of base stations. The geo-information portal has the ability to synchronize with the data of the radio frequency center. Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing will be able to receive up-to-date analytical data. There will be completely automated processes of collecting, processing and storing information on BS.

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Probiotics in gastroenterology – from a different angle

Orvosi Hetilap ◽

10.1556/oh.2013.29547 ◽

2013 ◽

Vol 154 (8) ◽

pp. 294-304 ◽

Cited By ~ 2

Author(s):

György Miklós Buzás

Keyword(s):

Side Effects ◽

Beneficial Effect ◽

Analytical Data ◽

Well Being ◽

Gastrointestinal Diseases ◽

Convincing Evidence ◽

Probiotic Treatment ◽

History Of ◽

Irritable Bowel

After a short overview of the history of probiotics, the author presents the development of human intestinal microflora based on the newest genetic data and the microbiological features of main probiotics. The indications of probiotic administration have been defined and extended in recent years. The author reviews significant results of probiotic treatment in some gastrointestinal diseases based on meta-analytical data. Probiotics are useful in preventing and treating diarrhoea caused by antibiotics and Clostridium difficile caused diarrhoea. In the treatment of Helicobacter pylori infection, preparations containing certain Lactobacillus,Bifidobacterium strains or Saccaromyces boulardii could enhance by 5–10% the rate of successful eradication and reduce the incidence and severity of the side effects. Some symptoms of irritable bowel syndrome and thus the quality of life can be improved by probiotics. Their beneficial effect in ulcerative colitis was proven, while in Crohn’s disease has not yet been defined. The use of probiotics is not included in guidelines, with the exception of the Maastricht IV/Florence consensus. For each disease it is advisable to use probiotics containing strains only with proven beneficial effect. The efficiency of preparations containing mixed strains has not yet been properly investigated. The author reviews the rare but potentially serious side effects of probiotics. In Hungary, there are many probiotic preparations available which can be purchased in pharmacies without prescription: their use is more empirical than evidence-based. The European Food Safety Authority has recently rejected claims for probiotics to be classed as medicines given the lack of convincing evidence on the effects of probiotics on human health and well-being. Clearly, further research is needed to collect evidence which could be incorporated into the international guidelines. Orv. Hetil., 2013, 154, 294–304.

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