In this paper, the effect of adding different concentrations of kinetic inhibitors on the induction time of hydrogen sulfide hydrate formation in a reactor equipped with automatic adjustable temperature controller is ...In this paper, the effect of adding different concentrations of kinetic inhibitors on the induction time of hydrogen sulfide hydrate formation in a reactor equipped with automatic adjustable temperature controller is studied. A novel method namely "sudden cooling" is used for performing the relevant measurements, in which the induction time of H2S hydrate in the presence/absence of PVP and L-tyrosine with different concentrations (100, 500, and 1000 ppm) is determined. As a result, PVP with the concentration of 1000 ppm in aqueous solution is detected as a more suitable material for increasing the induction time of H2S hydrate formation among the investigated kinetic hydrate inhibitors.展开更多
The high-resolution quantitative analysis of the planktonic foraminifera and the δ18O records of the section between 96.49– 137.6 mcd at ODP Site 1144 on the continental slope of northern South China Sea reveals an ...The high-resolution quantitative analysis of the planktonic foraminifera and the δ18O records of the section between 96.49– 137.6 mcd at ODP Site 1144 on the continental slope of northern South China Sea reveals an abrupt cooling event of sea surface temperature (SST) during the last interglacial (MIS 5.5, i.e. 5e). The dropping range of the winter SST may come to 7.5°C corresponding to 1.2‰ of the δ18O value of sea surface water. This event is comparable with those discovered in the west Europe and the northern Atlantic Ocean, but expressed in a more intensive way. It is inferred that this event may have been induced by middle- to low-latitude processes rather than by polar ice sheet change. Since the Kuroshio-index speciesPulleniatina obliquiloculata displayed the most distinct change at the event, it may also be related to the paleoceanographic change of the low-latitude area in the western Pacific Ocean. This event can be considered as one of “Younger Dryas-style coolings” and is indicative of climate variability of the last interglacial stage.展开更多
We analyze the relationships between strato- spheric polar vortex anomalies and cooling events in eastern China using isentropic reanalysis data from the European Center for Medium-Range Weather Forecasts. Daily mean ...We analyze the relationships between strato- spheric polar vortex anomalies and cooling events in eastern China using isentropic reanalysis data from the European Center for Medium-Range Weather Forecasts. Daily mean data from 2000 to 2011 are used to explore the effective stratospheric signals. First, diagnoses of the 2009/2010 winter show that after the stratospheric sudden warming (SSW) of the Atlantic-East Asian (AEA) pattern, the stratospheric high isentropic potential vorticity (IPV) center derived from the split polar vortex will move to the northeast of the Eurasian continent. The air mass, accom- panied by some southward and eastward movements and characterized by high IPV values, will be stretched verti- cally, leading to apparent reinforcements of the positive vorticity and the development of acold vortex system in the troposphere. The northerly wind on the western side of the cold vortex can transport cold air southward and down- ward, resulting in this distinct cooling process in eastern China. Secondly, the empirical orthogonal function ana- lyses of IPV anomalies on the 430 K isentropic surface during 2000-2011 winters indicate that the IPV distribution and time series of the first mode are able to represent the polar vortex variation features, which significantly influ- ence cold-air activity in eastern China, especially in the AEA-type SSW winter. When the time series increases significantly, the polar vortex will be split and the high-IPV center will move to the northeast of the Eurasian continent with downward and southward developments, inducing obvious cooling in eastern China. Moreover, all the four times SSW events of AEA pattern from 2000 to 2011 are reflected in the first time series, and after the strong polar vortex disturbances, cooling processes of different inten- sities are observed in eastern China. The cooling can sus- tain at least 1 week. For this reason, the first time series can be used as an available index of polar vortex oscillation and has the power to predict cold-air activity in winter.展开更多
文摘In this paper, the effect of adding different concentrations of kinetic inhibitors on the induction time of hydrogen sulfide hydrate formation in a reactor equipped with automatic adjustable temperature controller is studied. A novel method namely "sudden cooling" is used for performing the relevant measurements, in which the induction time of H2S hydrate in the presence/absence of PVP and L-tyrosine with different concentrations (100, 500, and 1000 ppm) is determined. As a result, PVP with the concentration of 1000 ppm in aqueous solution is detected as a more suitable material for increasing the induction time of H2S hydrate formation among the investigated kinetic hydrate inhibitors.
基金the National Natural Science Foundation of China (Grant No. 4999560).
文摘The high-resolution quantitative analysis of the planktonic foraminifera and the δ18O records of the section between 96.49– 137.6 mcd at ODP Site 1144 on the continental slope of northern South China Sea reveals an abrupt cooling event of sea surface temperature (SST) during the last interglacial (MIS 5.5, i.e. 5e). The dropping range of the winter SST may come to 7.5°C corresponding to 1.2‰ of the δ18O value of sea surface water. This event is comparable with those discovered in the west Europe and the northern Atlantic Ocean, but expressed in a more intensive way. It is inferred that this event may have been induced by middle- to low-latitude processes rather than by polar ice sheet change. Since the Kuroshio-index speciesPulleniatina obliquiloculata displayed the most distinct change at the event, it may also be related to the paleoceanographic change of the low-latitude area in the western Pacific Ocean. This event can be considered as one of “Younger Dryas-style coolings” and is indicative of climate variability of the last interglacial stage.
基金supported by the National Natural Science Foundation of China(41205041)Chinese Special Fund for Meteorology(GYHY201406020)+1 种基金National Basic Research Program of China(2012CB417205)LCS Open Funds for Young Scholars(2014)
文摘We analyze the relationships between strato- spheric polar vortex anomalies and cooling events in eastern China using isentropic reanalysis data from the European Center for Medium-Range Weather Forecasts. Daily mean data from 2000 to 2011 are used to explore the effective stratospheric signals. First, diagnoses of the 2009/2010 winter show that after the stratospheric sudden warming (SSW) of the Atlantic-East Asian (AEA) pattern, the stratospheric high isentropic potential vorticity (IPV) center derived from the split polar vortex will move to the northeast of the Eurasian continent. The air mass, accom- panied by some southward and eastward movements and characterized by high IPV values, will be stretched verti- cally, leading to apparent reinforcements of the positive vorticity and the development of acold vortex system in the troposphere. The northerly wind on the western side of the cold vortex can transport cold air southward and down- ward, resulting in this distinct cooling process in eastern China. Secondly, the empirical orthogonal function ana- lyses of IPV anomalies on the 430 K isentropic surface during 2000-2011 winters indicate that the IPV distribution and time series of the first mode are able to represent the polar vortex variation features, which significantly influ- ence cold-air activity in eastern China, especially in the AEA-type SSW winter. When the time series increases significantly, the polar vortex will be split and the high-IPV center will move to the northeast of the Eurasian continent with downward and southward developments, inducing obvious cooling in eastern China. Moreover, all the four times SSW events of AEA pattern from 2000 to 2011 are reflected in the first time series, and after the strong polar vortex disturbances, cooling processes of different inten- sities are observed in eastern China. The cooling can sus- tain at least 1 week. For this reason, the first time series can be used as an available index of polar vortex oscillation and has the power to predict cold-air activity in winter.