scholarly journals High Temperature Sulfate Minerals Forming on the Burning Coal Dumps from Upper Silesia, Poland

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 228
Author(s):  
Jan Parafiniuk ◽  
Rafał Siuda
Keyword(s):  
High Temperature ◽  
Volatile Components ◽  
Chemical Compositions ◽  
Near Surface ◽  
Vesicular Structure ◽  
Sulfate Minerals ◽  
Upper Silesian Coal Basin ◽  
Direct Measurements ◽  
The Subject ◽  
Burning Coal

The subject of this work is the assemblage of anhydrous sulfate minerals formed on burning coal-heaps. Three burning heaps located in the Upper Silesian coal basin in Czerwionka-Leszczyny, Radlin and Rydułtowy near Rybnik were selected for the research. The occurrence of godovikovite, millosevichite, steklite and an unnamed MgSO4, sometimes accompanied by subordinate admixtures of mikasaite, sabieite, efremovite, langbeinite and aphthitalite has been recorded from these locations. Occasionally they form monomineral aggregates, but usually occur as mixtures practically impossible to separate. The minerals form microcrystalline masses with a characteristic vesicular structure resembling a solidified foam or pumice. The sulfates crystallize from hot fire gases, similar to high temperature volcanic exhalations. The gases transport volatile components from the center of the fire but their chemical compositions are not yet known. Their cooling in the near-surface part of the heap results in condensation from the vapors as viscous liquid mass, from which the investigated minerals then crystallize. Their crystallization temperatures can be estimated from direct measurements of the temperatures of sulfate accumulation in the burning dumps and studies of their thermal decomposition. Millosevichite and steklite crystallize in the temperature range of 510–650 °C, MgSO4 forms at 510–600 °C and godovikovite in the slightly lower range of 280–450 (546) °C. These values are higher than those previously reported.

Analytical Electron Microscopy of Ion-Implanted Metals

1985 ◽  
Vol 43 ◽  
pp. 282-285
Author(s):  
D.I. Potter ◽  
M. Ahmed ◽  
K. Ruffing
Keyword(s):  
Electron Microscopy ◽  
Ion Implantation ◽  
Friction And Wear ◽  
Analytical Electron Microscopy ◽  
Chemical Compositions ◽  
Surface Chemical ◽  
Near Surface ◽  
The Past ◽  
Analytical Electron ◽  
Property Changes

Ion implantation, used extensively for the past decade in fabricating semiconductor devices, now provides a unique means for altering the near-surface chemical compositions and microstructures of metals. These alterations often significantly improve physical properties that depend on the surface of the material; for example, catalysis, corrosion, oxidation, hardness, friction and wear. Frequently the mechanisms causing these beneficial alterations and property changes remain obscure and much of the current research in the area of ion implantation metallurgy is aimed at identifying such mechanisms. Investigators thus confront two immediate questions: To what extent is the chemical composition changed by implantation? What is the resulting microstructure? These two questions can be investigated very fruitfully with analytical electron microscopy (AEM), as described below.

scholarly journals Secondary Metabolic Profile as a Tool for Distinction and Characterization of Cultivars of Black Pepper (Piper nigrum L.) Cultivated in Pará State, Brazil

2021 ◽  
Vol 22 (2) ◽  
pp. 890
Author(s):  
Luccas M. Barata ◽  
Eloísa H. Andrade ◽  
Alessandra R. Ramos ◽  
Oriel F. de Lemos ◽  
William N. Setzer ◽  
...  
Keyword(s):  
Black Pepper ◽  
Plant Diseases ◽  
Gas Chromatography Mass Spectrometry ◽  
Piper Nigrum ◽  
Volatile Components ◽  
Chemical Compositions ◽  
Multivariate Statistical ◽  
Protein Targets ◽  
Fruit Samples ◽  
Sesquiterpene Hydrocarbons

This study evaluated the chemical compositions of the leaves and fruits of eight black pepper cultivars cultivated in Pará State (Amazon, Brazil). Hydrodistillation and gas chromatography–mass spectrometry were employed to extract and analyze the volatile compounds, respectively. Sesquiterpene hydrocarbons were predominant (58.5–90.9%) in the cultivars “Cingapura”, “Equador”, “Guajarina”, “Iaçará”, and “Kottanadan”, and “Bragantina”, “Clonada”, and “Uthirankota” displayed oxygenated sesquiterpenoids (50.6–75.0%). The multivariate statistical analysis applied using volatile composition grouped the samples into four groups: γ-Elemene, curzerene, and δ-elemene (“Equador”/“Guajarina”, I); δ-elemene (“Iaçará”/“Kottanadan”/“Cingapura”, II); elemol (“Clonada”/“Uthirankota”, III) and α-muurolol, bicyclogermacrene, and cubebol (“Bragantina”, IV). The major compounds in all fruit samples were monoterpene hydrocarbons such as α-pinene, β-pinene, and limonene. Among the cultivar leaves, phenolics content (44.75–140.53 mg GAE·g−1 FW), the enzymatic activity of phenylalanine-ammonia lyase (20.19–57.22 µU·mL−1), and carotenoids (0.21–2.31 µg·mL−1) displayed significant variations. Due to black pepper’s susceptibility to Fusarium infection, a molecular docking analysis was carried out on Fusarium protein targets using each cultivar’s volatile components. F. oxysporum endoglucanase was identified as the preferential protein target of the compounds. These results can be used to identify chemical markers related to the susceptibility degree of black pepper cultivars to plant diseases prevalent in Pará State.

scholarly journals Evaluation on the Bond Capacity of the Fire-Protected FRP Bonded to Concrete Under High Temperature

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Soo-yeon Seo ◽  
Jong-wook Lim ◽  
Su-hyun Jeong
Keyword(s):  
High Temperature ◽  
Critical Temperature ◽  
Temperature Variation ◽  
Fire Resistance ◽  
Fire Protection ◽  
Element Analysis ◽  
External Temperature ◽  
Near Surface ◽  
Board Type ◽  
The Face

AbstractTo figure out the change in the reinforcing effect of FRP system used for the retrofit of RC beam when it is exposed to high temperature, it is required to evaluate not only the behavior of the entire beam, but also the bond performance at anchorage zone through a bond test according to the increase of external temperature. Moreover, the study to find various fire-protection methods is necessary to prevent the epoxy from reaching the critical temperature during an exposure to high temperature. In this manner, the fire-resistance performances of externally bonded (EB) FRP and near-surface-mounted (NSM) FRP to concrete block were evaluated by high-temperature exposure tests after performing a fire-protection on the surface in this paper. Board-type insulation with mortar was considered for the fire-protection of FRP system. After the fire-protection of the FRPs bonded to concrete blocks, an increasing exposure temperature was applied to the specimens with keeping a constant shear bond stress between concrete and the FRP. Based on the result, the temperature when the bond strength of the FRP disappears was evaluated. In addition, a finite element analysis was performed to find a proper method for predicting the temperature variation of the epoxy which is fire-protected with board-type insulation during the increase of external temperature. As a result of the test, despite the same fire-protection, NSM specimens were able to resist 1.54–2.08 times higher temperature than EB specimens. In the design of fire-protection of FRP system with the board-type insulation, it is necessary to consider the transfer from sides as well as the face with FRP. If there is no insulation of FP boards on the sides, the epoxy easily reaches its critical temperature by the heat penetrated to the sides, and increasing the thickness of the FP board alone for the face with FRP does not increase the fire-resistance capacity. As a result of the FE analysis, the temperature variation at epoxy can be predicted using the analytical approach with the proper thermal properties of FP mortar and board.

scholarly journals XIX.—Magnetization and Resistance of Nickel Wire at High Temperatures. Part II.

1907 ◽  
Vol 45 (3) ◽  
pp. 547-554
Author(s):  
C. G. Knott
Keyword(s):  
High Temperature ◽  
High Temperatures ◽  
Electrical Resistance ◽  
British Association ◽  
Nickel Wire ◽  
Present Communication ◽  
Association Meeting ◽  
The Subject ◽  
The Wire

The experiments which form the subject of the present communication were carried out two years ago, and supplement results already published. A brief note of some of the results was read before the Society in June 1904, and was also read before the British Association Meeting at Cambridge in August of the same year.The previous paper discussed the effect of high temperature on the relation between electrical resistance and magnetization when the wire was magnetized longitudinally, that is, in the direction in which the resistance was measured.The present results have to do with the effect of high temperature on the relation between resistance and magnetization when the magnetization was transverse to the direction along which the resistance was measured.

scholarly journals Chemical discrimination of the particulate and gas phases of miniCAST exhausts using a two-filter collection method

2019 ◽  
Author(s):  
Linh Dan Ngo ◽  
Dumitru Duca ◽  
Yvain Carpentier ◽  
Jennifer A. Noble ◽  
Raouf Ikhenazene ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Human Health ◽  
Gas Phase ◽  
Sampling Method ◽  
Volatile Components ◽  
Chemical Compositions ◽  
Laser Mass Spectrometry ◽  
Gas Phases ◽  
The Impact ◽  
Filter Sampling

Abstract. Combustion of hydrocarbons produces both particulate and gas phase emissions responsible for major impacts on atmospheric chemistry and human health. Ascertaining the impact of these emissions, especially on human health, is not straightforward because of our relatively poor knowledge of how chemical compounds are partitioned between the particle and gas phases. Accordingly, we propose to couple a two-filter sampling method with a multi-technique analytical approach to fully characterize the particulate and gas phase compositions of combustion by-products. The two-filter sampling method is designed to retain particulate matter (elemental carbon possibly covered in a surface layer of adsorbed molecules) on a first quartz fiber filter while letting the gas phase pass through, and then trap the most volatile components on a second black carbon-covered filter. All samples thus collected are subsequently subjected to a multi-technique analytical protocol involving two-step laser mass spectrometry (L2MS), secondary ion mass spectrometry (SIMS), and micro-Raman spectroscopy. Using the combination of this two-filter sampling/multi-technique approach in conjunction with advanced statistical methods we are able to unravel distinct surface chemical compositions of aerosols generated with different set points of a miniCAST burner. Specifically, we successfully discriminate samples by their volatile, semi-volatile and non-volatile polycyclic aromatic hydrocarbon (PAH) contents and reveal how subtle changes in combustion parameters affect particle surface chemistry.

scholarly journals Long-term trends in aerosol and precipitation composition over the western North Atlantic Ocean at Bermuda

2014 ◽  
Vol 14 (5) ◽  
pp. 7025-7066 ◽  
Author(s):  
W. C. Keene ◽  
J. L. Moody ◽  
J. N. Galloway ◽  
J. M. Prospero ◽  
O. R. Cooper ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Flow Regimes ◽  
The United States ◽  
Open Ocean ◽  
Anthropogenic Sources ◽  
Trade Wind ◽  
Chemical Compositions ◽  
Near Surface

Abstract. Since the 1980s, emissions of SO2 and NOx (NO + NO2) from anthropogenic sources in the United States (US) and Europe have decreased significantly suggesting that the export of oxidized S and N compounds from surrounding continents to the atmosphere overlying North Atlantic Ocean (NAO) has also decreased. The chemical compositions of aerosols and precipitation sampled daily on Bermuda (32.27° N, 64.87° W) from 1989 to 1997 and from 2006 to 2009 were evaluated to quantify the magnitudes, significance, and implications of associated tends in atmospheric composition. The chemical data were stratified based on FLEXPART retroplumes into four discrete transport regimes: westerly flow from the eastern North America (NEUS/SEUS); easterly trade-wind flow from northern Africa and the subtropical NAO (Africa); long, open-ocean, anticyclonic flow around the Bermuda High (Oceanic); and transitional flow from the relatively clean open ocean to the polluted northeastern US (North). Based on all data, annual average concentrations of non-sea-salt (nss) SO42- associated with aerosols and annual VWA concentrations in precipitation decreased significantly (by 22 and 49%, respectively) whereas annual VWA concentrations of NH4+ in precipitation increased significantly (by 70%). Corresponding trends in aerosol and precipitation NO3- and of aerosol NH4+ were insignificant. Nss SO42- in precipitation under NEUS/SEUS and Oceanic flow decreased significantly (61% each) whereas corresponding trends in particulate nss SO42- under both flow regimes were insignificant. Trends for precipitation were driven in part by decreasing emissions of SO2 over upwind continents and associated decreases in anthropogenic contributions to nss SO42- concentrations. Under NEUS/SEUS and Oceanic flow, the ratio of anthropogenic to biogenic contributions to to nss SO42- in the column scavenged by precipitation were relatively greater than those in near surface aerosol, which implies that, for these flow regimes, precipitation is a better indicator of overall anthropogenic impacts on the lower troposphere. Particulate nss SO42- under African flow also decreased significantly (34%) whereas the corresponding decrease in nss SO42- associated with precipitation was marginally insignificant. We infer that these trends were driven in part by reductions in the emissions and transport of oxidized S compounds from Europe. The lack of significant trends in NO3- associated with aerosols and precipitation under NEUS/SEUS flow is notable in light of the large decrease (39%) in NOx emissions in the US over the period of record. Rapid chemical processing of oxidized N in marine air contributed to this lack of correspondence. Decreasing ratios of nss SO42- to NH4+ and the significant decreasing trend in precipitation acidity (37%) indicate that the total amount of acidity in the multiphase gas-aerosol system in the western NAO troposphere decreased over the period of record. Decreasing aerosol acidities would have shifted the phase partitioning of total NH3 (NH3 + particulate NH4+) towards the gas phase thereby decreasing the atmospheric lifetime of total NH3 against wet plus dry deposition. The trend of increasing NH4+ in precipitation at Bermuda over the period of record suggests that NH3 emissions from surrounding continents also increased. Decreasing particulate nss SO42- in near-surface air under NEUS/SEUS flow over the period of record suggests a lower limit for net warming in the range of 0.1–0.3 W m-2 resulting from the decreased shortwave scattering and absorption by nss SO42- and associated aerosol constituents.

scholarly journals Seedability of Winter Orographic Clouds

1986 ◽  
Vol 43 ◽  
pp. 127-138 ◽  
Author(s):  
Geoffrey E. Hill
Keyword(s):  
Wind Speed ◽  
Liquid Water ◽  
Supercooled Liquid ◽  
Direct Measurements ◽  
Orographic Clouds ◽  
The Subject ◽  
Relationship Of ◽  
Increasing Precipitation ◽  
Cloud Top Temperature ◽  
Limiting Value

Abstract This article is a review of work on the subject of seedability of winter orographic clouds for increasing precipitation. Various aspects of seedability are examined in the review, including definitions, distribution of supercooled liquid water, related meteorological factors, relationship of supercooled liquid water to storm stage, factors governing seedability, and the use of seeding criteria. Of particular interest is the conclusion that seedability is greatest when supercooled liquid water concentrations are large and at the same time precipitation rates are small. Such a combination of conditions is favored if the cloud-top temperature is warmer than a limiting value and as the cross-barrier wind speed at mountaintop levels increases. It is also suggested that cloud seeding is best initiated in accordance with direct measurements of supercooled liquid water, precipitation, and cross-barrier wind speed. However, in forecasting these conditions or in continuation of seeding previously initiated, the cloud-top temperature and cross-barrier wind speed are the most useful quantities.

40 Ar— 39 Ar ages and irradiation history of Luna 24 basalts

1980 ◽  
Vol 297 (1428) ◽  
pp. 27-39 ◽  
Keyword(s):  
Solar Wind ◽  
High Temperature ◽  
Production Rate ◽  
Cosmic Ray ◽  
Spectral Information ◽  
Near Surface ◽  
Surface Sample ◽  
History Of ◽  
Impact Events ◽  
The Way

The Luna 24 mission sampled a variety of lithologies in a single core. Two of these lithologies, a metabasalt (24196) and a crushed basalt (24170) have been subjected to 40 Ar- 39 Ar dating experiments to determine if metamorphism significantly post-dated basalt extrusion. The metabasalt exhibited symptoms of both solar wind contamination and 39 Ar recoil; in view of these effects an age may only be defined by making extreme assumptions. High temperature release fractions give an age of 3.36 ± 0.11 Ga, while the cumulate 40 Ar/ 39 Ar ratio gives 3.14 ± 0.16 Ga; both are comparable with the basalt (24170) age and suggest that the metabasalts represent thermally penecontemporaneously metamorphosed flow margins, rather than the products of later impact events. The feldspar from the microgabbro yielded an age of 3.37 ± 0.20 Ga. The ratios of cosmogenic 38 Ar to Ca in pyroxene and feldspar are within error identical, indicating that 38 Ar production from Fe in the pyroxene is small. This is the first definitive use of Fe-produced 38 Ar as a spectral hardness indicator and implies that the microgabbro received much of its cosmic ray exposure at depth in the regolith. By taking account of the dependence of 38 Ar production rate with depth it is inferred that the microgabbro layer was deposited within the last 350-500 Ma. By implication, the regolith layers above the microgabbro at the Luna 24 site are younger. The metabasalt has an identical cosmogenic 38 Ar/Ca ratio; however, because of the decrease of production rate with depth it could have experienced a 20 % pre-exposure before deposition of the microgabbro. Spectral information has also been obtained from a reappraisal of published argon data and indicates a much harder spectrum for a near surface sample. The way in which the Ca- and Fe-produced 38 Ar e follow the broad trend of the instantaneous production profiles suggests that the regolith at the Luna 24 site has been relatively undisturbed for much of the last 300 Ma.

scholarly journals Comparison of Volatiles of Sideritis caesarea Specimens Collected from Different Localities in Turkey

2017 ◽  
Vol 12 (10) ◽  
pp. 1934578X1701201
Author(s):  
Tuğba Günbatan ◽  
Betül Demirci ◽  
İlhan Gürbüz ◽  
Fatih Demircib ◽  
Ayşe Mine Gençler Özkanc
Keyword(s):  
Gas Chromatography ◽  
Folk Medicine ◽  
Volatile Components ◽  
Chemical Compositions ◽  
Moderate Activity ◽  
Caryophyllene Oxide ◽  
Hexadecanoic Acid ◽  
Flame Ionization ◽  
Main Components

Sideritis caesarea H. Duman, Aytaç & Başer of the Lamiaceae is an Anatolian endemic species, and is mainly used as herbal tea and folk medicine. This present study aimed to determine and compare the chemical compositions of the volatile components of S. caesarea specimens collected from different localities in Kayseri province, Turkey: Sariz town (samples A and B), Pınarbaşı-Kaynar (sample C) and Pınarbaşı-Şirvan Mountain (sample D), respectively. Initially, the essential oils of the aerial parts were obtained by hydrodistillation and analysed both by gas chromatography-flame ionization detector (GC-FID), gas chromatography/mass spectrometer (GC/MS), simultaneously. Major volatile components of samples A and D were characterized as hexadecanoic acid (19.7 and 20.5%), caryophyllene oxide (6.7 and 20.2%), β-caryophyllene (6.5 and 12.6%), respectively. In sample B, hexadecanoic acid (14.6%), β-caryophyllene (11.5%) and caryophyllene oxide (8.3%) were detected as the major components. Whereas caryophyllene oxide (13.7%), hexadecanoic acid (8.5%) and spathulenol (6.1%) were the main components of the essential oil of sample C. Besides the chemical profiling, in vitro antimicrobial effects of samples were evaluated against a panel of six pathogenic microorganisms. Inhibition zones of the tested samples varied against bacteria with low to moderate activity, where no susceptibility against Candida albicans was observed.

scholarly journals Simultaneous Measurements of Chemical Compositions of Fine Particles during Winter Haze Period in Urban Sites in China and Korea

Atmosphere ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 292 ◽  
Author(s):  
Minhan Park ◽  
Yujue Wang ◽  
Jihyo Chong ◽  
Haebum Lee ◽  
Jiho Jang ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Fine Particles ◽  
Chemical Compositions ◽  
Aerosol Formation ◽  
Wind Speeds ◽  
Simultaneous Measurements ◽  
Dust Sources ◽  
Secondary Formation ◽  
Combustion Sources ◽  
Burning Coal

We performed simultaneous measurements of chemical compositions of fine particles in Beijing, China and Gwangju, Korea to better understand their sources during winter haze period. We identified PM2.5 events in Beijing, possibly caused by a combination of multiple primary combustion sources (biomass burning, coal burning, and vehicle emissions) and secondary aerosol formation under stagnant conditions and/or dust sources under high wind speeds. During the PM2.5 events in Gwangju, the contribution of biomass burning and secondary formation of nitrate and organics to the fine particles content significantly increased under stagnant conditions. We commonly observed the increases of nitrogen-containing organic compounds and biomass burning inorganic (K+) and organic (levoglucosan) markers, suggesting the importance of biomass burning sources during the winter haze events (except dust event cases) at both sites. Pb isotope ratios indicated that the fraction of Pb originated from possibly industry and coal combustion sources increased during the PM2.5 events in Gwangju, relative to nonevent days.

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