Based on experiments with the Community Earth System Model, version 1(Community Atmosphere Model, version 5)[CESM1(CAM5)], and an observational dataset, we found that CESM1-CAM5 is able to reproduce global monsoon(GM)...
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Based on experiments with the Community Earth System Model, version 1(Community Atmosphere Model, version 5)[CESM1(CAM5)], and an observational dataset, we found that CESM1-CAM5 is able to reproduce global monsoon(GM)features, including the patterns of monsoon precipitation and monsoon domains, the magnitude of GM precipitation(GMP,the local summer precipitation), GM area(GMA), and GM percentage(the ratio of the local summer precipitation to annual precipitation). Under the Paris Agreement temperature goals, the GM in CESM1-CAM5 displays the following changes:(1)The GMA is ambiguous under the 1.5℃ temperature goal and increases under the 2.0℃ temperature goal. The increase mainly results from a change in the monsoon percentage.(2) The GM, land monsoon and ocean monsoon precipitation all significantly increase under both the 1.5℃ and 2.0℃ goals. The increases are mainly due to the enhancement of humidity and evaporation.(3) The percentages of GM, land monsoon and ocean monsoon feature little change under the temperature goals.(4) The lengths of the GM, land monsoon and ocean monsoon are significantly prolonged under the temperature *** increase in precipitation during the monsoon withdrawal month mainly accounts for the prolonged monsoons. Regarding the differences between the 1.5℃ and 2.0℃ temperature goals, it is certain that the GMP displays significant *** addition, a large-scale enhancement of ascending motion occurs over the southeastern Tibetan Plateau and South China under a warming climate, whereas other monsoon areas experience an overall decline in ascending motion. This leads to an extraordinary wetting over Asian monsoon areas.
To improve the oxidation properties of ferritic heat-resistant steels,an Al-bearing 9Cr‒5Si‒3Al ferritic heat-resistant steel was *** then conducted cyclic oxidation tests to investigate the high-temperature oxidation...
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To improve the oxidation properties of ferritic heat-resistant steels,an Al-bearing 9Cr‒5Si‒3Al ferritic heat-resistant steel was *** then conducted cyclic oxidation tests to investigate the high-temperature oxidation behavior of 9Cr‒5Si and 9Cr‒5Si‒3Al ferritic heat-resistant steels at 900 and 1000℃.The characteristics of the oxide layer were analyzed by X-ray diffraction,scanning electron microscopy,and energy dispersive *** results show that the oxidation kinetics curves of the two tested steels follow the parabolic law,with the parabolic rate constant kp of 9Cr‒5Si‒3Al steel being much lower than that of 9Cr‒5Si steel at both 900 and 1000℃.The oxide film on the surface of the 9Cr‒5Si alloy exhibits Cr2MnO4 and Cr2O3 phases in the outer layer after oxidation at 900 and 1000℃.However,at oxidation temperatures of 900 and 1000℃,the oxide film of the 9Cr‒5Si‒3Al alloy consists only of Al2O3 and its oxide layer is thinner than that of the 9Cr‒5Si *** results indicate that the addition of Al to the 9Cr‒5Si steel can improve its high-temperature oxidation resistance,which can be attributed to the formation of a continuous and compact Al2O3 film on the surface of the steel.
RNA viruses cause a multitude of human diseases,including several pandemic events in the past *** viral invasion,the innate immune system responds rapidly and plays a key role in activating the adaptive immune *** the...
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RNA viruses cause a multitude of human diseases,including several pandemic events in the past *** viral invasion,the innate immune system responds rapidly and plays a key role in activating the adaptive immune *** the innate immune system,the interactions between pathogen-associated molecular patterns and host pattern recognition receptors activate multiple signaling pathways in immune cells and induce the production of pro-inflammatory cytokines and interferons to elicit antiviral ***,dendritic cells,and natural killer cells are the principal innate immune components that exert antiviral *** this review,the current understanding of innate immunity contributing to the restriction of RNA viral infections was briefly *** the main role of immune cells in combating viral infection,the intercellular transfer of pathogen and host-derived materials and their epigenetic and metabolic interactions associated with innate immunity was *** knowledge provides an enhanced understanding of the innate immune response to RNA viral infections in general and aids in the preparation for the existing and next emerging viral infections.
A negligible depletion-solid phase microextraction (nd-SPME) method is developed to measure free concentrations of two alkyl phenols (4-t-octylphenol, nonylphenol) and bisphenol A in activated sludge, with which aerob...
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A negligible depletion-solid phase microextraction (nd-SPME) method is developed to measure free concentrations of two alkyl phenols (4-t-octylphenol, nonylphenol) and bisphenol A in activated sludge, with which aerobic biodegradation kinetics of three pollutants was determined. For the degradation of octylphenol, nonylphenol and bisphenol A, the apparent rate constant based on total concentration is 0.02, 0.01 and 0.03 h-1, respectively; with the half life being 34.9, 54.3 and 22.3 h correspondingly. Meanwhile, real rate constants based on free concentration are 0.74, 0.60 and 1.03 h-1, respectively; with the half life being 0.9, 1.2 and 0.7 h accordingly. Differences between two constants revealed that desorption of targeted pollutants from activated sludge should be the rate-limiting step. Compared to the rapid biodegradation of alkyl phenols and bisphenol A in free state, the desorption of pollutants from the sludge is relatively slow, which made the apparent biodegradation rate constants much lower.
We compared the regional synoptic patterns and local meteorological conditions during persistent and non-persistent pollution events in Beijing using US NCEP–Department of Energy reanalysis outputs and observations f...
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We compared the regional synoptic patterns and local meteorological conditions during persistent and non-persistent pollution events in Beijing using US NCEP–Department of Energy reanalysis outputs and observations from meteorological stations. The analysis focused on the impacts of high-frequency(period 〈 90 days) variations in meteorological conditions on persistent pollution events(those lasting for at least 3 days). Persistent pollution events tended to occur in association with slow-moving weather systems producing stagnant weather conditions, whereas rapidly moving weather systems caused a dramatic change in the local weather conditions so that the pollution event was short-lived. Although Beijing was under the influence of anomalous southerly winds in all four seasons during pollution events, notable differences were identified in the regional patterns of sea-level pressure and local anomalies in relative humidity among persistent pollution events in different seasons. A region of lower pressure was present to the north of Beijing in spring, fall, and winter, whereas regions of lower and higher pressures were observed northwest and southeast of Beijing, respectively, in summer. The relative humidity near Beijing was higher in fall and winter, but lower in spring and summer. These differences may explain the seasonal dependence of the relationship between air pollution and the local meteorological variables. Our analysis showed that the temperature inversion in the lower troposphere played an important part in the occurrence of air pollution under stagnant weather *** results from this study are based on a limited number of events and thus require validation using more data.
The Li-O_(2) batteries have ttrcted much attention due to their parallel theoretical energy density to *** the past 20 years,understanding and knowledge in Li-O_(2) battlry have greatly deepened in elucidat-ing the re...
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The Li-O_(2) batteries have ttrcted much attention due to their parallel theoretical energy density to *** the past 20 years,understanding and knowledge in Li-O_(2) battlry have greatly deepened in elucidat-ing the relationship between structure and *** group has been focusing on the cathode en-gineering and anode protection strategy development in the past years,trying to make full use of the supe-riority of metal-air batteries towards *** this review,we aim to retrospect our efforts in devel-oping practical,sustainable metal-air *** will first introduce the basic working principle of Li-O_(2) batteries and our progresses in L-O_(2) batteries with typical cathode designs and anode protection strategies,which have together promoted the large capacity,long life and low charge *** emphasize the designing art of carbon-based cathodes in this part along with a short talk on all-metal *** fol-lowing part is our research in Na-O2 batteries including both cathode and anode *** differ-ences between Li-O2 and Na-O2 batteries are also briefly ***,our proof-of-concept work on Li-N2 battery,a new energy storage system and chemistry,is discussed with detailed information on the discharge product ***,we summarize our designed models and prototypes of flex-ible metal-air batteries that are promising to be used in flexible devices to deliver more power.
System management is becoming increasingly complex and brings high costs, especially with the advent of cloud computing. Cloud computing involves numerous platforms often of virtual machines (VMs) and middleware has...
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System management is becoming increasingly complex and brings high costs, especially with the advent of cloud computing. Cloud computing involves numerous platforms often of virtual machines (VMs) and middleware has to be managed to make the whole system work cost- effectively after an application is deployed. In order to re- duce management costs, in particular for the manual activi- ties, many computer programs have been developed remove or reduce the complexity and difficulty of system mamnage- ment. These programs are usually hard-coded in languages like Java and C++, which bring enough capability and flexi- bility but also cause high programming effort and cost. This paper proposes an architecture for developing management programs in a simple but powerful way. First of all, the man- ageability of a given platform (via APIs, configuration files, and scripts) is abstracted as a runtime model of the plat- form's software architecture, which can automatically and immediately propagate any observable runtime changes of the target platforms to the corresponding architecture mod- els, and vice versa. The management programs are devel- oped using modeling languages, instead of those relatively low-level programming languages. Architecture-level man- agement programs bring many advantages related to perfor- mance, interoperability, reusability, and simplicity. An experiment on a real-world cloud deployment and comparison with traditional programming language approaches demonstrate the feasibility, effectiveness, and benefits of the new model based approach for management program development.
Based on the concept of East Asia-Pacific (EAP) teleconnection which influences East Asian summer monsoon, an index for East Asian summer monsoon circulation anomaly was defined and it was pointed out that this index ...
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Based on the concept of East Asia-Pacific (EAP) teleconnection which influences East Asian summer monsoon, an index for East Asian summer monsoon circulation anomaly was defined and it was pointed out that this index can describle the interannual variation character of summer climate in East Asia, especially in the Yangtze River and Huaihe River Valley.
The effect of bainite transformation and microstructure on the mechanical properties in 0.3%C bainitic steel was investigated via the heat treatment process of quenching at higher initial temperature and partitioning ...
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The effect of bainite transformation and microstructure on the mechanical properties in 0.3%C bainitic steel was investigated via the heat treatment process of quenching at higher initial temperature and partitioning below martensite-start temperature. The results show that bainite transformation takes place with the partitioning time increasing during partitioning below martensite-start temperature. The microstructure of samples treated by this two-step quenching and partitioning process consists of lath bainite, lath martensite and retained austenite. This kind of multiphase microstructure exhibits better strength of 1420 MPa, ductility of 21.8 % and the product of strength and elongation of 30.8 GPa%. Furthermore, the excellent impact toughness of 103 J is exhibited by partitioning at 280 ℃ for 3 h. In addition, the coalescence of bainite platelets was found in the sample treated by partitioning for 8 h, leading to the deterioration of toughness.
The present study investigates meteorological conditions for the day-to-day changes of particulate matter (PM) concentration in Beijing city during the period 2008-2015. The local relationship of PM concentration to...
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The present study investigates meteorological conditions for the day-to-day changes of particulate matter (PM) concentration in Beijing city during the period 2008-2015. The local relationship of PM concentration to surface air temperature, pressure, wind speed, and relative humidity displays seasonal changes and year-to-year variations. The average correlation coefficient with PMI0 in spring, summer, fall, and winter is 0.45, 0.40, 0.38, and 0.30 for air tem- perature; -0.45, -0.05, -0.40, and -0.45 for pressure; 0.13, 0.04, 0.53, and 0.50 for relative humidity; and -0.18, -0.11, -0.45, and -0.33 for wind speed. A higher correlation with wind speed is obtained when wind speed leads by halfa day. The heavily polluted and clean days, which are defined as the top and bottom 10% of the PM values, show obvious differences in the regional distribution of air temperature, pressure, and wind. Polluted days correspond to higher air temperature in all the four seasons, lower sea level pressure and anomalous southerly winds to the south and east of Beijing in spring, fall, and winter, and a northwest-southeast contrast in the pressure anomaly and anom- alous southerly winds in summer. Higher relative humidity is observed on polluted days in fall and winter. The pol- luted days are preceded by an anomalous cyclone moving from the northwest, accompanied by lower pressure and higher air temperature, in all four seasons. This feature indicates the impacts of moving weather systems on local meteorological conditions for day-to-day air quality changes in Beijing.
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