Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for p...Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for predicting change over time.Surface soil samples from six ecoregions of the United States were analyzed for permanganate oxidizable C(KMnO4-C)and mineralizable C pools.Variations of SOC ranged from 7.9 mg g^-1(Florida site)to 325 mg g^-1(Hawaii site).Mineralisable C pools and KMnO4-C were highest in soils from the Hawaii site.Mean annual precipitation explains SOC and resistant C pool variations.Clay content was related to mineralisable active C pools and bacterial abundance.Mean annual precipitation and clay content are potential variables for predicting changes in SOC pools at large spatial scales.展开更多
The development of electric and hybrid automobiles has gained momentum with the growth of interest in the field of miniaturization of electrode materials. In particular, technologies that improve the electrical proper...The development of electric and hybrid automobiles has gained momentum with the growth of interest in the field of miniaturization of electrode materials. In particular, technologies that improve the electrical property of stainless steel, while maintaining corrosion resistance, are gaining interest in terms of maintaining specific resistivity. The study on metal doping in diamond-like carbon coating is currently in progress to enhance the characteristics of conductivity and corrosion resistance with excellent properties such as corrosion resistance and lubrication coating. It is the process of using Cr arc with DLC coating to actuate AEGD. The change of I(D)/I(G) (Graphite peak (G) and disordered bond peak (D)) ratio and G-peak position in Cr-containing DLC film causes graphitization and thus lowers the basic electric resistance. Simultaneous input of nitrogen gas leads to deposition of CrN by a specific ratio of Cr and N in the DLC coating, and the nitrogen atoms replace hydrogen in bonding to increase the sp3 bond structure in the DLC film, in which CrN is not deposited, to result in specific resistivity of a specific value or less.展开更多
The dynamics of soil organic carbon （SOC） was analyzed by using laboratory incubation and double exponential model that mineralizable SOC was separated into active carbon pools and slow carbon pools in forest soils ...The dynamics of soil organic carbon （SOC） was analyzed by using laboratory incubation and double exponential model that mineralizable SOC was separated into active carbon pools and slow carbon pools in forest soils derived from Changbai and Qilian Mountain areas. By analyzing and fitting the CO2 evolved rates with SOC mineralization, the results showed that active carbon pools accounted tor 1.0% to 8.5% of SOC with an average of mean resistant times （MRTs） for 24 days, and slow carbon pools accounted for 91% to 99% of SOC with an average of MRTs for 179 years. The sizes and MRTs of slow carbon pools showed that SOC in Qilian Mountain sites was more difficult to decompose than that in Changbai Mountain sites. By analyzing the effects of temperature, soil clay content and elevation on SOC mineralization, results indicated that mineralization of SOC was directly related to temperature and that content of accumulated SOC and size of slow carbon pools from Changbai Mountain and Qilian Mountain sites increased linearly with increasing clay content, respectively, which showed temperature and clay content could make greater effect on mineralization of SOC.展开更多
基金This project was supported by the North Dakota Agricultural Experiment Station,North Dakota State University(FARG007858).
文摘Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for predicting change over time.Surface soil samples from six ecoregions of the United States were analyzed for permanganate oxidizable C(KMnO4-C)and mineralizable C pools.Variations of SOC ranged from 7.9 mg g^-1(Florida site)to 325 mg g^-1(Hawaii site).Mineralisable C pools and KMnO4-C were highest in soils from the Hawaii site.Mean annual precipitation explains SOC and resistant C pool variations.Clay content was related to mineralisable active C pools and bacterial abundance.Mean annual precipitation and clay content are potential variables for predicting changes in SOC pools at large spatial scales.
文摘The development of electric and hybrid automobiles has gained momentum with the growth of interest in the field of miniaturization of electrode materials. In particular, technologies that improve the electrical property of stainless steel, while maintaining corrosion resistance, are gaining interest in terms of maintaining specific resistivity. The study on metal doping in diamond-like carbon coating is currently in progress to enhance the characteristics of conductivity and corrosion resistance with excellent properties such as corrosion resistance and lubrication coating. It is the process of using Cr arc with DLC coating to actuate AEGD. The change of I(D)/I(G) (Graphite peak (G) and disordered bond peak (D)) ratio and G-peak position in Cr-containing DLC film causes graphitization and thus lowers the basic electric resistance. Simultaneous input of nitrogen gas leads to deposition of CrN by a specific ratio of Cr and N in the DLC coating, and the nitrogen atoms replace hydrogen in bonding to increase the sp3 bond structure in the DLC film, in which CrN is not deposited, to result in specific resistivity of a specific value or less.
基金The research was funded by National Natural Science Foundation （40231016） and Canadian International Development Agency （CIDA）.
文摘The dynamics of soil organic carbon （SOC） was analyzed by using laboratory incubation and double exponential model that mineralizable SOC was separated into active carbon pools and slow carbon pools in forest soils derived from Changbai and Qilian Mountain areas. By analyzing and fitting the CO2 evolved rates with SOC mineralization, the results showed that active carbon pools accounted tor 1.0% to 8.5% of SOC with an average of mean resistant times （MRTs） for 24 days, and slow carbon pools accounted for 91% to 99% of SOC with an average of MRTs for 179 years. The sizes and MRTs of slow carbon pools showed that SOC in Qilian Mountain sites was more difficult to decompose than that in Changbai Mountain sites. By analyzing the effects of temperature, soil clay content and elevation on SOC mineralization, results indicated that mineralization of SOC was directly related to temperature and that content of accumulated SOC and size of slow carbon pools from Changbai Mountain and Qilian Mountain sites increased linearly with increasing clay content, respectively, which showed temperature and clay content could make greater effect on mineralization of SOC.
