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241.
Hydrothermally altered rocks are frequently encountered when tunnels are constructed in Hokkaido, Japan. High concentraions of hazardous elements, such as arsenic (As), are often released from these rocks into the surrounding environments. Therefore, the rocks are considered potentially hazardous waste. This article describes the effects of water content and oxygen (O2) concentration in relation to additional layer(s), i.e., surface covering and bottom adsorption layers, on As leaching by using laboratory columns with water content and O2 concentration sensors. The results show that the use of additional layer(s) has a significant effect on lowering As migration. This was due not only to the adsorption capacity of As by the adsorption layer but also to the water content and O2 concentration inside the rock layer. The accumulation of pore water was increased in the rock layer in cases with additional layer(s), which resulted in lower O2 concentration in the rock layer. Consequently, the leaching of As by the oxidation of As-bearing minerals in the rock layer was reduced. Moreover, a longer water-resident time in the rock layer may induce precipitation of Fe oxy-hydroxide/oxide. These results suggest that the geochemical conditions of the rock layer affect As leaching and migration. 相似文献
242.
Satoshi Kagiwada Yusuke Kayano Hideo Hoshi Takeshi Kawanishi Kenro Oshima Hiroshi Hamamoto Hiromichi Horie Shigetou Namba 《Journal of General Plant Pathology》2010,76(5):345-347
In summer 2007, leaf and stem rot of ice plants was found in a hydroponic greenhouse in Japan. The causal agent was a fungus
identified as Choanephora cucurbitarum (Berkeley & Ravenel) Thaxter, based on pathogenicity, morphology, mating tests, and sequence analysis of the ribosomal DNA
ITS region. 相似文献
243.
Four genes encoding glycoside hydrolase (GH) family 6 and 7 cellulases (cel6A, cel6B, cel7A, and cel7B) were obtained from the brown-rot fungus Coniophora puteana by genomic polymerase chain reaction (PCR) using consensus degenerate hybrid oligonucleotide primers (CODEHOPs) designated
from the amino acid sequence of cellobiohydrolases (CBHs) from white-rot fungi. The nucleotide sequences of four genes showed
high homology with basidiomycetes CBHs, suggesting the fi rst cloning of the genes encoding Cel6 and Cel7 from brown-rot fungi.
PCR using CODEHOP pairs at the catalytic domain successfully amplifi ed both cel6A and cel6B, whereas only cel6A fragment was obtained using the primers including the carbohydrate-binding modules (CBMs), suggesting lack of CBM in Cel6B.
Moreover, both cel7A and cel7B were amplified by the PCR using CODEHOP pairs at the catalytic domain, but not by those including CBM, suggesting the absence
of Cel7 with CBM in the fungus. From these results, three of four cellulases from C. puteana may not carry CBM, which has an important role for the degradation of crystalline cellulose. 相似文献