A chilling-repressed cDNA fragment was cloned from rice ( Oryza sativa L.) seedlings by reverse transcription-polymerase chain reaction (RT-PCR) differential display. Database comparison of the cDNA sequence is identi...A chilling-repressed cDNA fragment was cloned from rice ( Oryza sativa L.) seedlings by reverse transcription-polymerase chain reaction (RT-PCR) differential display. Database comparison of the cDNA sequence is identical to atpH encoded by rice chloroplast genome. Northern hybridization showed that its RNA transcript was reduced greatly on the first day and fully inhibited after 2 d of chilling treatment.展开更多
Using the UVic Earth System Model, this study simulated the change of seawater chemistry and analyzed the chemical habitat surrounding shallow- and cold-water coral reefs from the year 1800 to 2300 employing RCP2.6, R...Using the UVic Earth System Model, this study simulated the change of seawater chemistry and analyzed the chemical habitat surrounding shallow- and cold-water coral reefs from the year 1800 to 2300 employing RCP2.6, RCP4.5, RCP6.0, and RCP8.5 scenarios. The model results showed that the global ocean will continue to absorb atmospheric CO2. Global mean surface ocean temperature will rise 1.1-2.8 K at the end of the 21st century across RCP scenarios. Meanwhile, the global mean surface ocean pH will drop 0.14--0.42 and the ocean surface mean con- centration of carbonate will decrease 20%--51% across the RCP scenarios. The saturated state of sea water with respect to calcite carbonate minerals (t2) will decrease rapidly. During the pre-industrial period, 99% of the shallow-water coral reefs were surrounded by seawater with t2 〉 3.5 and 87% of the deep-sea coral reefs were surrounded by seawater with aragonite supersaturation. Within the 21st century, except for the high mitigation scenario of RCP2.6, almost none shallow-water coral reefs will be surrounded by seawater with g2 〉 3.5. Under the intensive emission scenario of RCP8.5, by the year 2100, the aragonite saturation horizon will rise to 308 m under the sea surface from 1138 m at the pre- industrial period, thus 73% of the cold-water coral reefs will be surrounded by seawater with aragonite undersaturation. By the year 2300, only 5% of the cold-water coral reefs will be surrounded by seawater with aragonite supersaturation.展开更多
An experimental investigation of natural gas hydrate formation has been conducted in a high-pressure water spraying reactor,which is cooled by the circulation water through an external cooling jacket.The results show ...An experimental investigation of natural gas hydrate formation has been conducted in a high-pressure water spraying reactor,which is cooled by the circulation water through an external cooling jacket.The results show that the morphology of hydrates formed by water spraying is like ice-slurry,which depends on the initial pressure and temperature.At a certain reaction pressure,the rate of hydrate formation is increasing with lower temperature.And also,the induction time of hydrate formation can be greatly shortened by water spraying compared to a quiescent system.Solution with appropriate surfactant sodium dodecyl sulfate (SDS) is found to improve the formation rate obviously.展开更多
This paper discusses the long-term temperature variation of the Southern Yellow Sea Cold Water Mass(SYSCWM)and examines those factors that infl uence the SYSCWM,based on hydrographic datasets of the China National Sta...This paper discusses the long-term temperature variation of the Southern Yellow Sea Cold Water Mass(SYSCWM)and examines those factors that infl uence the SYSCWM,based on hydrographic datasets of the China National Standard Section and the Korea Oceanographic Data Center.Surface air temperature,meridional wind speed,and sea surface temperature data are used to describe the seasonal changes.Mean temperature of the two centers of the SYSCWM had diff erent long-term trends.The temperature of the center in the west of the SYSCWM was rising whereas that of the center in the east was falling.Mean temperature of the western center was related to warm water intrusion of the Yellow Sea Warm Current,the winter meridional wind,and the winter air temperature.Summer process played a primary role in the cooling trend of temperature in the eastern center.A decreasing trend of salinity in the eastern half of the SYSCWM showed that warm water intrusion from the south might weaken,as could the SYSCWM circulation.Weakened circulation provided less horizontal heat input to the eastern half of the SYSCWM.Less lateral heat input may have led to the decreasing trend in temperature of the eastern center of the SYSCWM.Further,warmer sea surface temperatures and less heat input in the deep layers intensifi ed the thermocline of the eastern SYSCWM.A stronger thermocline had less heat fl ux input from upper layers to this half of the SYSCWM.Stronger thermocline and weakened heat input can be seen as two main causes of the cooling temperature trend of the eastern center of the SYSCWM.展开更多
Adopting the approximation to the first order of chemical potential μ, we resolve rigidly the influence on fermion condensate from μ in QED3. We show that this condensate does not respond linear expression to μ. Mo...Adopting the approximation to the first order of chemical potential μ, we resolve rigidly the influence on fermion condensate from μ in QED3. We show that this condensate does not respond linear expression to μ. Moreover, the influence on fermion chiral condensate from chemieal potential is investigated.展开更多
Regarding the lack of cold source for underground cooling systems from either mine inflow or return air, field experiments were taken in a high temperature deep coal mine with abundant cold source from surface water. ...Regarding the lack of cold source for underground cooling systems from either mine inflow or return air, field experiments were taken in a high temperature deep coal mine with abundant cold source from surface water. Taking Sanhejian coal mine as an example, this paper introduced the technology scheme of heat disaster governance using surface water cold source. The paper presents the basics of this field experiment at the beginning, following by the design and site layout of the cooling system including the analysis and calculation of cold source. Numerical calculation method is also applied based on the operation parameters to simulate the influence to the surface river ecosystem. The results suggest that the temperature of surface water shall be lower than 34 ℃ after heat exchange, and when more cooling capacities are needed in the future, increasing the water flow is more favorable than increasing the cooling range of water, which is better for the ecological environment protection,展开更多
DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study...DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study, methylation-sensitive amplified polymorphisms (MSAP) were used to investigate DNA methylation profiles of cassava polyploidy following cold treatment to identify candidate genes involved in response to cold stress. The result showed that the genome-wide DNA methylation polymorphisms accounted for 34.02%-42.56% in SC8 and its autotetraploid exposed to 5 ~C for 2, 8, 24 and 48 h, respectively. The methylation levels of SC8 at 2 h-cold stress were the highest during 48h under cold treatments. With the time extension within 48 h under cold stress, the methylation levels gradually decreased to the same level as the control but DNA methylation levels of cassava autotetraploid were stable within 48 h. For future analysis of the methylation extent, the cold stress induced more DNA methylation than demethylation in SC8, where DNA methylation was consistent with demethylation in its autotetraploid. The expression analysis demonstrated increase in the transcription of one methylated gene and decrease in the transcription of two demethylated genes. The results revealed that gene methylations in specific sites would be a rapidly epigenetic response to cold stress, further elucidating the methylation functions in its autotetraploid.展开更多
The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-ge...The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-gel method on a red copper test plate.From the obtained fluorescence images,the phase transition characteristics during the freezing and melting process of a water droplet were clearly observed.It was found that,at the beginning of the droplet freezing process,liquid water turned into ice at a very fast rate.Such phase transition process decreased gradually with time and the volume of frozen ice approached a constant value at the end of the icing process.In addition,the freezing time was found to reduce with the decrease of the test plate temperature.Besides,when the test plate temperature is relatively high,the effect of droplet volume on the freezing time is very significant.Over all,we provide some tentative insights into the microphysical process related to the icing and melting process of water droplets.展开更多
For environmental protection, energy conservation, and other reasons, water-based lubricants are increasingly chosen to replace oil lubricants. Water-based lubricants are divided into emulsified and solution types. So...For environmental protection, energy conservation, and other reasons, water-based lubricants are increasingly chosen to replace oil lubricants. Water-based lubricants are divided into emulsified and solution types. Solution type water-based lubricants have attracted significant attention for the good stability, easy biodegradability, and safety for workers. However, some problems exist with current solution type water-based lubricants, such as poor lubricity and corrosion resistance. During the cold-rolling process, A1 plate rolled using oil-based lubricant lubrication shows metallic luster, but that rolled using water-based lubricant shows corrosion spots, black strips, and no metallic luster. Therefore, this study mainly analyzed the reasons for the darkness of A1 plate cold-rolled with water solution lubricants. The differences in plate surfaces lubricated by water solution and oil were investigated by scanning electron microscopy, auger electron spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The analysis results showed that the surface of the oil-lubricated sample is smooth, the oxygen content is low, and the oxide layer is thin, while the surface of the water solution-lubricated sample is rough, the oxygen content is high, the chemical composition is more complex, and the oxide layer is not uniform and thick.展开更多
文摘A chilling-repressed cDNA fragment was cloned from rice ( Oryza sativa L.) seedlings by reverse transcription-polymerase chain reaction (RT-PCR) differential display. Database comparison of the cDNA sequence is identical to atpH encoded by rice chloroplast genome. Northern hybridization showed that its RNA transcript was reduced greatly on the first day and fully inhibited after 2 d of chilling treatment.
基金supported by National Natural Science Foundation of China(41276073,41422503)National Key Basic Research Program of China(2015CB953601)+1 种基金Zhejiang University K.P.Chao's High Technology Development Foundationthe Fundamental Research Funds for the Central Universities
文摘Using the UVic Earth System Model, this study simulated the change of seawater chemistry and analyzed the chemical habitat surrounding shallow- and cold-water coral reefs from the year 1800 to 2300 employing RCP2.6, RCP4.5, RCP6.0, and RCP8.5 scenarios. The model results showed that the global ocean will continue to absorb atmospheric CO2. Global mean surface ocean temperature will rise 1.1-2.8 K at the end of the 21st century across RCP scenarios. Meanwhile, the global mean surface ocean pH will drop 0.14--0.42 and the ocean surface mean con- centration of carbonate will decrease 20%--51% across the RCP scenarios. The saturated state of sea water with respect to calcite carbonate minerals (t2) will decrease rapidly. During the pre-industrial period, 99% of the shallow-water coral reefs were surrounded by seawater with t2 〉 3.5 and 87% of the deep-sea coral reefs were surrounded by seawater with aragonite supersaturation. Within the 21st century, except for the high mitigation scenario of RCP2.6, almost none shallow-water coral reefs will be surrounded by seawater with g2 〉 3.5. Under the intensive emission scenario of RCP8.5, by the year 2100, the aragonite saturation horizon will rise to 308 m under the sea surface from 1138 m at the pre- industrial period, thus 73% of the cold-water coral reefs will be surrounded by seawater with aragonite undersaturation. By the year 2300, only 5% of the cold-water coral reefs will be surrounded by seawater with aragonite supersaturation.
基金National Natural Science Foundation of China(No.50706028)Shanghai Leading Academic Discipline Project,China(No.S30503)
文摘An experimental investigation of natural gas hydrate formation has been conducted in a high-pressure water spraying reactor,which is cooled by the circulation water through an external cooling jacket.The results show that the morphology of hydrates formed by water spraying is like ice-slurry,which depends on the initial pressure and temperature.At a certain reaction pressure,the rate of hydrate formation is increasing with lower temperature.And also,the induction time of hydrate formation can be greatly shortened by water spraying compared to a quiescent system.Solution with appropriate surfactant sodium dodecyl sulfate (SDS) is found to improve the formation rate obviously.
基金Supported by the National Natural Science Foundation of China(Nos.41176018,41376031,41206020)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA11020301)the NSFCShandong Joint Fund for Marine Science Research Centers(No.U1406401)
文摘This paper discusses the long-term temperature variation of the Southern Yellow Sea Cold Water Mass(SYSCWM)and examines those factors that infl uence the SYSCWM,based on hydrographic datasets of the China National Standard Section and the Korea Oceanographic Data Center.Surface air temperature,meridional wind speed,and sea surface temperature data are used to describe the seasonal changes.Mean temperature of the two centers of the SYSCWM had diff erent long-term trends.The temperature of the center in the west of the SYSCWM was rising whereas that of the center in the east was falling.Mean temperature of the western center was related to warm water intrusion of the Yellow Sea Warm Current,the winter meridional wind,and the winter air temperature.Summer process played a primary role in the cooling trend of temperature in the eastern center.A decreasing trend of salinity in the eastern half of the SYSCWM showed that warm water intrusion from the south might weaken,as could the SYSCWM circulation.Weakened circulation provided less horizontal heat input to the eastern half of the SYSCWM.Less lateral heat input may have led to the decreasing trend in temperature of the eastern center of the SYSCWM.Further,warmer sea surface temperatures and less heat input in the deep layers intensifi ed the thermocline of the eastern SYSCWM.A stronger thermocline had less heat fl ux input from upper layers to this half of the SYSCWM.Stronger thermocline and weakened heat input can be seen as two main causes of the cooling temperature trend of the eastern center of the SYSCWM.
基金Supported in Part by the Science Foundation of Southeast UniversityChina Postdoctoral Science Foundation Funded Project under Grant No.20070420192
文摘Adopting the approximation to the first order of chemical potential μ, we resolve rigidly the influence on fermion condensate from μ in QED3. We show that this condensate does not respond linear expression to μ. Moreover, the influence on fermion chiral condensate from chemieal potential is investigated.
基金supported by the Key Project of National Natural Science Foundation‘‘Deep Heat Governance and Utilization’’(No.51134005)the Doctoral Fund of Ministry of Education(No.20120023120004)
文摘Regarding the lack of cold source for underground cooling systems from either mine inflow or return air, field experiments were taken in a high temperature deep coal mine with abundant cold source from surface water. Taking Sanhejian coal mine as an example, this paper introduced the technology scheme of heat disaster governance using surface water cold source. The paper presents the basics of this field experiment at the beginning, following by the design and site layout of the cooling system including the analysis and calculation of cold source. Numerical calculation method is also applied based on the operation parameters to simulate the influence to the surface river ecosystem. The results suggest that the temperature of surface water shall be lower than 34 ℃ after heat exchange, and when more cooling capacities are needed in the future, increasing the water flow is more favorable than increasing the cooling range of water, which is better for the ecological environment protection,
文摘DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study, methylation-sensitive amplified polymorphisms (MSAP) were used to investigate DNA methylation profiles of cassava polyploidy following cold treatment to identify candidate genes involved in response to cold stress. The result showed that the genome-wide DNA methylation polymorphisms accounted for 34.02%-42.56% in SC8 and its autotetraploid exposed to 5 ~C for 2, 8, 24 and 48 h, respectively. The methylation levels of SC8 at 2 h-cold stress were the highest during 48h under cold treatments. With the time extension within 48 h under cold stress, the methylation levels gradually decreased to the same level as the control but DNA methylation levels of cassava autotetraploid were stable within 48 h. For future analysis of the methylation extent, the cold stress induced more DNA methylation than demethylation in SC8, where DNA methylation was consistent with demethylation in its autotetraploid. The expression analysis demonstrated increase in the transcription of one methylated gene and decrease in the transcription of two demethylated genes. The results revealed that gene methylations in specific sites would be a rapidly epigenetic response to cold stress, further elucidating the methylation functions in its autotetraploid.
基金supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry and Science and Techology Commission of Shanghai Municipality(Grant No.11DZ2260400)
文摘The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-gel method on a red copper test plate.From the obtained fluorescence images,the phase transition characteristics during the freezing and melting process of a water droplet were clearly observed.It was found that,at the beginning of the droplet freezing process,liquid water turned into ice at a very fast rate.Such phase transition process decreased gradually with time and the volume of frozen ice approached a constant value at the end of the icing process.In addition,the freezing time was found to reduce with the decrease of the test plate temperature.Besides,when the test plate temperature is relatively high,the effect of droplet volume on the freezing time is very significant.Over all,we provide some tentative insights into the microphysical process related to the icing and melting process of water droplets.
基金supported by the National Key Basic Research Program of China(Grant No.2013CB934200)the National Natural Science Foundation of China(Grant Nos.51335005&51527901)
文摘For environmental protection, energy conservation, and other reasons, water-based lubricants are increasingly chosen to replace oil lubricants. Water-based lubricants are divided into emulsified and solution types. Solution type water-based lubricants have attracted significant attention for the good stability, easy biodegradability, and safety for workers. However, some problems exist with current solution type water-based lubricants, such as poor lubricity and corrosion resistance. During the cold-rolling process, A1 plate rolled using oil-based lubricant lubrication shows metallic luster, but that rolled using water-based lubricant shows corrosion spots, black strips, and no metallic luster. Therefore, this study mainly analyzed the reasons for the darkness of A1 plate cold-rolled with water solution lubricants. The differences in plate surfaces lubricated by water solution and oil were investigated by scanning electron microscopy, auger electron spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The analysis results showed that the surface of the oil-lubricated sample is smooth, the oxygen content is low, and the oxide layer is thin, while the surface of the water solution-lubricated sample is rough, the oxygen content is high, the chemical composition is more complex, and the oxide layer is not uniform and thick.