85 research outputs found
The mineralogical composition of calcium and calcium-magnesium carbonate pedofeatures of calcareous soils in the European prairie ecodivision in Hungary
Abstract
There is little data on the mineralogy of carbonate pedofeatures in the calcareous soils in Hungary which belong to the European prairie ecodivision. The aim of the present study is to enrich these data.
The mineralogical composition of the carbonate pedofeatures from characteristic profiles of the calcareous soils in Hungary was studied by X-ray diffractometry, thermal analysis, SEM combined with microanalysis, and stable isotope determination.
Regarding carbonate minerals only aragonite, calcite (+ magnesian calcite) and dolomite (+proto-dolomite) were identified in carbonate grains, skeletons and pedofeatures.
The values relating, respectively, to stable isotope compositions (C13, O18) of carbonates in chernozems and in salt-affected soils were in the same range as those for recent soils (latter data reported earlier). There were no considerable differences between the values for the carbonate nodules and tubules from the same horizons, nor were there significant variations between the values of the same pedofeatures from different horizons (BC-C) of the same profile. Thus it can be assumed that there were no considerable changes in conditions of formation.
Tendencies were recognized in the changes of (i) carbonate mineral associations, (ii) the MgCO3 content of calcites, (iii) the corrected decomposition temperatures, and (iv) the activation energies of carbonate thermal decompositions among the various substance-regimes of soils.
Differences were found in substance-regimes types of soils rather than in soil types
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
The comparative study of trihalomethanes in drinking water
The purpose of this study was to assess exposure of four
trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane
and bromoform) in drinking waters of Okinawa Island and Samoa.
Trihalomethanes compounds were determined in the drinking water samples
that were collected from the selected consumption sites and treatment
plants of both Okinawa and Samoa in 2003-2004. The Chatan and Nishihara
Water Treatment Plants (Okinawa) uses both ozonation and chlorination
for primary and secondary disinfection. For Samoa Water Treatment
Plants only chlorination is used as primary disinfection. Results
showed that the mean concentration of trihalomethanes from treatment
plants in Okinawa ranged from 0.30 ± 1.81 μg/L to 11 ±
2.68 μg/L and from the consumption sites ranged from 2.08 ±
0.32 μg/L to 19.39 ± 100 μg/L. In comparison, the mean
concentration of trihalomethanes from the treatment plants in Samoa
ranged from 226 ± 81.2 μg/L to 267 ± 92.3 μg/L and
from the consumption sites were in the ranges 212 ± 101 μg/L
to 387 ± 125 μg/L. Brominated compounds were commonly seen in
all samples collected in Okinawa. Among the trihalomethanes compounds,
chloroform was the common detected trihalomethanes in the samples
collected from Samoa. The trihalomethanes levels in all samples
collected in Okinawa and Samoa were generally below the guideline
values in Japan, but some samples displayed levels which exceeded the
level of Japan Water Quality and WHO Standards for chlorinated and
brominated compounds
High-temperature operations of rotation angle sensors with spin-valve-type magnetic tunnel junctions
Contamination and impacts of new antifouling biocide Irgarol-1051 on subtropical coral reef waters
Coral reefs are deteriorating worldwide due to various stresses,
including pollution of hazardous chemicals such as antifouling
chemicals. Occurrence and impacts of a new antifouling biocide
Irgarol-1051 (2-methylthio-4-tert- butylamino -6-cyclopropylamino
-s-triazine) have been studied in coral reef waters around Okinawa
Islands, Japan. The average concentration of Irgarol detected at
commercial and fisheries Ports was 24.70 ± 9.88 ng/L. In Naha Bay,
the average concentration of Irgarol was 10.00±12.98 ng/L. The
average level detected around the Ports has already approaches the
environmental risk limit for the marine organisms. Irgarol was detected
in waters at the frequency of 92.3 % (24/26) of the total samples
collected during two sampling campaigns (September and December, 2007)
at the Ports. In Naha Bay, Irgarol was detected by 40.5 % (17/42) of
the total water samples collected monthly from Sep., 2007 to Feb.,
2008, indicating that Irgarol is widely detected along the coastal
shorelines of Okinawa Island. The eco-toxicological study revealed that
the rate of photosynthesis in the coral Galaxea fascicularis was
significantly reduced by 18 % and 121 % relative to control when the
corals were exposed to 1000 and 10,000 ng/L of Irgarol, respectively.
The calcification rate dropped by 98.3 % relative to control when the
corals were exposed to 10,000 ng/L of Irgarol. The results of the
present study report the wide occurrence of new antifouling biocide
Irgarol around coastal areas of Okinawa Island. However, the
contamination does not pose serious threat on the photosynthesis and
calcification of corals under short term exposure (96 h)
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