Sulfide stress corrosion cracking (SSCC) behaviour of UNS G11180 steel in 5% NaCl solution with H2S was studied by slow strain rate tensile test (SSRT), SEM and electrochemical hydro gen permeation technique. The resu...Sulfide stress corrosion cracking (SSCC) behaviour of UNS G11180 steel in 5% NaCl solution with H2S was studied by slow strain rate tensile test (SSRT), SEM and electrochemical hydro gen permeation technique. The results reveal different cracking mechanism and H permeation current (IH) through UNS G11180 steel plate in different concentration of H2S solution. The susceptibility to SSCC of UNS G11180 Steel in 5% NaCl solution with H2S was evaluated by the permeation current(IH, μA), which depends on the concentration (c×10-6) of H2S by the equation:IH = 8.525 ×c0.7249. lt is proved that the electrochemical H permeation method is a practical way to assess the susceptibility to SSCC.展开更多
Objective:To examine the taxonomic boundaries in the Stellantchasmus populations in different hosts and reveal the cryptic speciation of the Stellantchasmus in Thailand based on both morphological and molecular approa...Objective:To examine the taxonomic boundaries in the Stellantchasmus populations in different hosts and reveal the cryptic speciation of the Stellantchasmus in Thailand based on both morphological and molecular approaches.Methods:Stellantchasmus falcatus(S.falcatus) s.l.was collected from different hosts throughout Thailand.The worms were examined and measured.The nuclear ITS2 gene and the mitochondrial COI gene were used to investigate the S.falcatus s.l.from Dermogenus pusillus and Liza subviridis.Results:Stellantchasmus was one of food-borne trematode that widely distribute throughout Thailand.The comparison of S.falcatus s.l.from Dermogenus pusillus and Liza subviridis indicated a genetic divergence of nuD NA with 3.6% and mtD NA with 19.3%,respectively.Morphological characteristics were fairly different in the ratio of body size,length of prepharynx,and ratio of organ size.Conclusions:Our results provide initial evidence that S.falcatus s.l.from different hosts tend to be a different species based on both molecular and morphological characters.Cryptic species complexes are generally found among parasites that tend to have large populations and/or rapid evolution.The degree of genetic diversity existing would suggest the practice of targeted regimes to design and minimize these lections of anthelmintic resistance in the future.展开更多
Pedogenic processes can explain the trends in magnetic susceptibility and soil magneticmineralogy of the Ljubljana Basin chronosequence. The chronosequence formed in predominantlycarbonate sandy gravel outwash terrace...Pedogenic processes can explain the trends in magnetic susceptibility and soil magneticmineralogy of the Ljubljana Basin chronosequence. The chronosequence formed in predominantlycarbonate sandy gravel outwash terraces ranging from 5 to 1800 ka. Magnetic susceptibilityenhancement can be attributed to the formation of secondary superparamagnetic （SP） and singledomain （SD） ferrimagnetic minerals in eluvial horizons. Magnetic minerals that form in illuvialhorizons are predominantly antiferromagnetic. Downward migration of pedogenic iron compoundswith clay （formation of ferri-argillans） causes thickening of the enhanced zone with soil age.In contrast to other published soil chronosequence studies, magnetic susceptibility values donot increase with soil-age （duration of pedogenesis）. Nevertheless, frequency dependence ofmagnetic susceptibility （FD%） and indices such as maximum eluvial magnetic susceptibility （MS）divided by minimum illuvial MS (Max. E / Min. IX<sub>lf</sub> and maximum eluvial MS minus minimumilluvial MS (Max. E -Min. IX<sub>lf</sub>) increase with the logarithm of soil age suggesting that the magneticmineral transformations continue with time, but that their rate decreases. These indices are usefulfor comparisons, and may be useful for age correlations. Hypothesis that magnetic susceptibilityenhancement and precipitation have a positive correlation seems to be valid until the precipitationexceeds the critical value of 100-150 cm/year. The critical value in different settings may dependon the temperature regime and on the yearly distribution of precipitation.展开更多
文摘Sulfide stress corrosion cracking (SSCC) behaviour of UNS G11180 steel in 5% NaCl solution with H2S was studied by slow strain rate tensile test (SSRT), SEM and electrochemical hydro gen permeation technique. The results reveal different cracking mechanism and H permeation current (IH) through UNS G11180 steel plate in different concentration of H2S solution. The susceptibility to SSCC of UNS G11180 Steel in 5% NaCl solution with H2S was evaluated by the permeation current(IH, μA), which depends on the concentration (c×10-6) of H2S by the equation:IH = 8.525 ×c0.7249. lt is proved that the electrochemical H permeation method is a practical way to assess the susceptibility to SSCC.
基金supported by National Research Council of Thailand(NRCT)to CW(grant number 2559A10402051,2016)The Thailand Research Fund to NN(grant number TRG5880053)
文摘Objective:To examine the taxonomic boundaries in the Stellantchasmus populations in different hosts and reveal the cryptic speciation of the Stellantchasmus in Thailand based on both morphological and molecular approaches.Methods:Stellantchasmus falcatus(S.falcatus) s.l.was collected from different hosts throughout Thailand.The worms were examined and measured.The nuclear ITS2 gene and the mitochondrial COI gene were used to investigate the S.falcatus s.l.from Dermogenus pusillus and Liza subviridis.Results:Stellantchasmus was one of food-borne trematode that widely distribute throughout Thailand.The comparison of S.falcatus s.l.from Dermogenus pusillus and Liza subviridis indicated a genetic divergence of nuD NA with 3.6% and mtD NA with 19.3%,respectively.Morphological characteristics were fairly different in the ratio of body size,length of prepharynx,and ratio of organ size.Conclusions:Our results provide initial evidence that S.falcatus s.l.from different hosts tend to be a different species based on both molecular and morphological characters.Cryptic species complexes are generally found among parasites that tend to have large populations and/or rapid evolution.The degree of genetic diversity existing would suggest the practice of targeted regimes to design and minimize these lections of anthelmintic resistance in the future.
文摘Pedogenic processes can explain the trends in magnetic susceptibility and soil magneticmineralogy of the Ljubljana Basin chronosequence. The chronosequence formed in predominantlycarbonate sandy gravel outwash terraces ranging from 5 to 1800 ka. Magnetic susceptibilityenhancement can be attributed to the formation of secondary superparamagnetic （SP） and singledomain （SD） ferrimagnetic minerals in eluvial horizons. Magnetic minerals that form in illuvialhorizons are predominantly antiferromagnetic. Downward migration of pedogenic iron compoundswith clay （formation of ferri-argillans） causes thickening of the enhanced zone with soil age.In contrast to other published soil chronosequence studies, magnetic susceptibility values donot increase with soil-age （duration of pedogenesis）. Nevertheless, frequency dependence ofmagnetic susceptibility （FD%） and indices such as maximum eluvial magnetic susceptibility （MS）divided by minimum illuvial MS (Max. E / Min. IX<sub>lf</sub> and maximum eluvial MS minus minimumilluvial MS (Max. E -Min. IX<sub>lf</sub>) increase with the logarithm of soil age suggesting that the magneticmineral transformations continue with time, but that their rate decreases. These indices are usefulfor comparisons, and may be useful for age correlations. Hypothesis that magnetic susceptibilityenhancement and precipitation have a positive correlation seems to be valid until the precipitationexceeds the critical value of 100-150 cm/year. The critical value in different settings may dependon the temperature regime and on the yearly distribution of precipitation.
