scholarly journals Mesofauna at the Soil-Scree Interface in a Deep Karst Environment

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 242
Author(s):  
Nikola Jureková ◽  
Natália Raschmanová ◽  
Dana Miklisová ◽  
Ľubomír Kováč
Keyword(s):  
Distributional Pattern ◽  
Ecological Groups ◽  
High Carbon ◽  
High Carbon Content ◽  
Community Patterns ◽  
Cold Adapted ◽  
Karst Environment ◽  
Subterranean Species ◽  
Subterranean Environment ◽  
High Diversity

The community patterns of Collembola (Hexapoda) were studied at two sites along a microclimatically inversed scree slope in a deep karst valley in the Western Carpathians, Slovakia, in warm and cold periods of the year, respectively. Significantly lower average temperatures in the scree profile were noted at the gorge bottom in both periods, meaning that the site in the lower part of the scree, near the bank of creek, was considerably colder and wetter compared to the warmer and drier site at upper part of the scree slope. Relatively high diversity of Collembola was observed at two fieldwork scree sites, where cold-adapted species, considered climatic relicts, showed considerable abundance. The gorge bottom, with a cold and wet microclimate and high carbon content even in the deeper MSS horizons, provided suitable environmental conditions for numerous psychrophilic and subterranean species. Ecological groups such as trogloxenes and subtroglophiles showed decreasing trends of abundance with depth, in contrast to eutroglophiles and a troglobiont showing an opposite distributional pattern at scree sites in both periods. Our study documented that in terms of soil and subterranean mesofauna, colluvial screes of deep karst gorges represent (1) a transition zone between the surface and the deep subterranean environment, and (2) important climate change refugia.

ALGOMA AR225

Alloy Digest ◽  
2003 ◽  
Vol 52 (12) ◽  
Keyword(s):  
Carbon Steel ◽  
Chemical Analysis ◽  
Physical Properties ◽  
Carbon Content ◽  
Brinell Hardness ◽  
Low Cost ◽  
Heat Treating ◽  
Rolled Plate ◽  
High Carbon ◽  
High Carbon Content

Abstract Algoma AR225 is a carbon steel developed primarily to supply a low-cost material for high-abrasion applications. It is furnished in the form of as-rolled plate with a relatively high carbon content (0.35-0.45%). AR-225 is sold on the basis of chemical analysis only; the number 225 signifies the approximate Brinell hardness. On thicknesses one-half inch and over, this Brinell value may be lower than 225 because of higher finishing temperatures. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, and joining. Filing Code: CS-138. Producer or source: Algoma Steel Corporation Ltd.

Polyimide as carbon and ceramic polysilazane precursors to obtain high carbon content ceramic for high-temperature applications

2020 ◽  
Author(s):  
André V. B. Andrade ◽  
Luiz F. Belchior Ribeiro ◽  
Emanoelle Diz Acosta ◽  
Fernando J. Da Costa ◽  
Maíra D. Mallmann ◽  
...  
Keyword(s):  
High Temperature ◽  
Carbon Content ◽  
High Carbon ◽  
High Carbon Content ◽  
Temperature Applications

Effects of Carbon Concentration Upon Oxygen Precipitation in Cz Si

1987 ◽  
Vol 104 ◽  
Author(s):  
S. Hahn ◽  
M. Arst ◽  
K. N. Ritz ◽  
S. Shatas ◽  
H. J. Stein ◽  
...  
Keyword(s):  
Carbon Content ◽  
Carbon Concentration ◽  
High Carbon ◽  
High Carbon Content ◽  
Oxygen Precipitation ◽  
Oxygen Precipitate ◽  
High Carbon Concentration ◽  
Precipitation Characteristics ◽  
C Complex ◽  
Oxide Precipitate

ABSTRACTEffects of high carbon concentration upon oxygen precipitate formation in Cz silicon have been investigated by combining various furnace and rapid thermal annneals. Even though oxide precipitate density increases with increasing carbon levels, Cs, synchrotron radiation section topographs of processed high carbon content wafers (Cs ∼ 4ppma) exhibit Pendellosung fringes, indicating a strain free bulk state. Our optical microscopic data have also shown very few defect etch features inside the bulk. A model based upon a direct coupling of both SiO2 and Si-C complex formation reactions is used to explain rather unique oxygen precipitation characteristics in the high carbon content Cz Si materials.

Geographical review of the ostracod genus Vestalenula (Darwinulidae) and a new subterranean species from southern France

2007 ◽  
Vol 21 (5) ◽  
pp. 471 ◽  
Author(s):  
Malvina Artheau
Keyword(s):  
New Record ◽  
Cladistic Analysis ◽  
Left Valve ◽  
Southern France ◽  
Recent Species ◽  
European Program ◽  
The Right ◽  
Subterranean Species ◽  
A New Species ◽  
Subterranean Environment

A new species of Vestalenula is described. Vestalenula carveli, sp. nov. was found in the interstitial habitat of rivers during the PASCALIS European program when sampling three sites on the Aude River and Tech River basins (Roussillon region, southern France). With its large caudal brooding cavity, the presence of an external keel on the right valve and an internal tooth on the left valve, V. carveli is a typical representative of the genus. This new record brings the worldwide number of Vestalenula species to 24. Vestalenula representatives are known from the Lower Miocene to the present. A review of present-day knowledge of the geographical distribution of the genus and a cladistic analysis are presented in order to assess the biogeography of this genus and the importance of the discovery of a new subterranean species in southern France. The geographical review of the genus showed that most species of Vestalenula occur in subtropical regions. However, V. cylindrica, V. boteai and V. danielopoli lived, or are living, in the Palearctic. Vestalenula pagliolii occurs in both hemispheres. Many of the Recent species live in semiterrestrial and/or interstitial habitats and occur in geographically restricted areas. The distribution of the species of Vestalenula suggests independent colonisation of the subterranean environment by several species; this hypothesis is supported by the cladistic analysis.

Synthesis of high carbon content microspheres using 2-step microwave carbonization, and the influence of nitrogen doping on catalytic activity

Carbon ◽  
2013 ◽  
Vol 60 ◽  
pp. 307-316 ◽  
Author(s):  
Alum Jung ◽  
Suenghoon Han ◽  
Teawon Kim ◽  
Won Joon Cho ◽  
Kun-Hong Lee
Keyword(s):  
Catalytic Activity ◽  
Carbon Content ◽  
Nitrogen Doping ◽  
High Carbon ◽  
High Carbon Content

scholarly journals Brazilian obligatory subterranean fauna and threats to the hypogean environment

ZooKeys ◽  
2018 ◽  
Vol 746 ◽  
pp. 1-23 ◽  
Author(s):  
Jonas Eduardo Gallão ◽  
Maria Elina Bichuette
Keyword(s):  
Raw Materials ◽  
Iucn Red List ◽  
Red List ◽  
Small Scale ◽  
Conservation Actions ◽  
Terrestrial Habitats ◽  
Hydroelectric Projects ◽  
Selective Regime ◽  
Subterranean Species ◽  
Subterranean Environment

The subterranean environment harbors species that are not capable of establishing populations in the epigean environment, i.e., the obligatory subterranean species. These organisms live in a unique selective regime in permanent darkness and usually low food availability, high air humidity in terrestrial habitats, and low temperature range allied to other unique conditions related to lithologies and past climatic influences. The pressure to increase Brazil’s economic growth relies on agricultural/pastoral industries and exporting of raw materials such as iron, limestone, ethanol, soybean, cotton, and meat, as well as huge reservoir constructions to generate electricity. Mining (even on a small scale), agricultural expansion, and hydroelectric projects are extremely harmful to subterranean biodiversity, via the modification and even destruction of hypogean habitats. The Brazilian subterranean species were analyzed with respect to their distributions, presence on the IUCN Red List, and current and potential threats to hypogean habitats. A map and three lists are presented, one with the described obligatory subterranean species, one with undescribed taxa, and one with the current and potential threats to the hypogean environment. To date, 150 obligatory subterranean species have been recorded in Brazil, plus at least 156 undescribed troglomorphic taxa, totaling 306 Brazilian troglobites/obligatory cave fauna. We also analyzed the current and potential cave threats and the conservation actions that are underway to attempt to compensate for loss of these habitats. In according to the Brazilian legislation (Decree 6640) only caves of maximum relevance are fully protected. One strategy to protect the subterranean fauna of Brazil is the inclusion of these species in the IUCN Red List (one of attributes that determines maximum relevance for caves); however, one of the IUCN assumptions is that the taxa must be formally described. It is clear that the description and proposed protection of Brazilian subterranean biodiversity depends on more systematics studies.

Failure Investigation of 1st Stage Buckets From Frame 3002, 10 MW Gas Turbine Unit

2011 ◽  
Author(s):  
Girish M. Shejale ◽  
David Ross
Keyword(s):  
Gas Turbine ◽  
Test Results ◽  
High Carbon ◽  
High Carbon Content ◽  
Metallurgical Investigation ◽  
Root Cause ◽  
Failure Investigation ◽  
Surface Failure ◽  
Grain Boundary Embrittlement ◽  
Industrial Gas Turbine

The 1st stage buckets in Frame 3002, 10 MW industrial gas turbine experienced premature failures. The buckets failed unexpectedly much earlier than the designed bucket life. Bucket material is Inconel 738, with platinum-aluminized coating on the surface. Failure investigation of the buckets was performed to know the root cause of the failure. The failure investigation primarily comprised of metallurgical investigation. The results of the metallurgical investigation were co-related with the unit operational history. This paper provides an overview of 1st stage buckets investigation. The metallurgical investigation performed concluded prime failure mechanism due to high carbon content of bucket material and improper heat treatment. The bucket coating was initially damaged during the first loading and fracture occurred due to grain boundary embrittlement in short span of service. The metallurgical tests performed included Visual inspection, Scanning Electron Microscopy (SEM), Energy Dispersive Analysis of X-ray (EDS), Chemical analysis, Tensile test and Hardness survey. The test results, discussions and conclusions are presented in this paper.

scholarly journals Comparative Assessment of Biochar Stability Using Multiple Indicators

Agronomy ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 254 ◽  
Author(s):  
Keiji Jindo ◽  
Tomonori Sonoki
Keyword(s):  
Oryza Sativa L ◽  
Chemical Oxidation ◽  
Assessment Method ◽  
Malus Pumila ◽  
Stable Carbon ◽  
High Carbon ◽  
High Carbon Content ◽  
Multiple Indicators ◽  
Different Temperatures ◽  
Incubation Method

Biochar application is one strategy proposed to improve carbon sequestration in soil. Maintaining high carbon content in soil for a long period requires stable biochar. In this work, we assessed biochar stability by two methodologies, i.e., laboratory incubation and chemical oxidation. Biochar was produced at four different temperatures (400 °C, 500 °C, 600 °C, and 800 °C) from rice (Oryza sativa L.) straw and husk, applewood branch (Malus pumila), and oak (Quercus serrata Murray) residues. Results showed that the high-temperature biochars were more stable in both abiotic and biotic incubations, whereas the low-temperature biochars had reduced longevity. In addition, we showed biochars originated from woody material have higher stable carbon than those produced from rice residues. Finally, the oxidative assessment method provided a more reliable estimation of stability than the biotic incubation method and showed a strong correlation with other stability indicators.

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