Updating eucalyptus carbon stock data in a timely manner is essential for better understanding and quantifying its effects on ecological and hydrological processes.At present,there are no suitable methods to accuratel...Updating eucalyptus carbon stock data in a timely manner is essential for better understanding and quantifying its effects on ecological and hydrological processes.At present,there are no suitable methods to accurately estimate the eucalyptus carbon stock in a large area.This research aimed to explore the transferability of the eucalyptus carbon stock estimation model at temporal and spatial scales and assess modeling performance through the strategy of combining sample plots,airborne LiDAR and Landsat time series data in subtropical regions of China.Specifically,eucalyptus carbon stock estimates in typical sites were obtained by applying the developed models with the combination of airborne LiDAR and field measurement data;the eucalyptus plantation ages were estimated using the random localization segmentation approach from Landsat time series data;and regional models were developed by linking LiDAR-derived eucalyptus carbon stock and vegetation age(e.g.,months or years).To examine the models’robustness,the developed models at the regional scale were transferred to estimate carbon stocks at the spatial and temporal scales,and the modeling results were evaluated using validation samples accordingly.The results showed that carbon stock can be successfully estimated using the age-based models(both age variables in months and years as predictor variables),but the month-based models produced better estimates with a root mean square error(RMSE)of 6.51 t⋅ha1 for Yunxiao County,Fujian Province,and 6.33 t⋅ha1 for Gaofeng Forest Farm,Guangxi Zhuang Autonomous Region.Particularly,the month-based models were superior for estimating the carbon stocks of young eucalyptus plantations of less than two years.The model transferability analyses showed that the month-based models had higher transferability than the year-based models at the temporal scale,indicating their possibility for analysis of carbon stock change.However,both the month-based and year-based models expressed relatively poor transferability at a spatial scale.This study provides new insights for cost-effective monitoring of carbon stock change in intensively managed plantation forests.展开更多
In this study,the effect of decarburization annealing temperature and time on the carbon content,microstructure,and texture of grain-oriented pure iron was investigated by optical microscopy and scanning electron micr...In this study,the effect of decarburization annealing temperature and time on the carbon content,microstructure,and texture of grain-oriented pure iron was investigated by optical microscopy and scanning electron microscopy with electron-backscatter diffraction. The results showed that the efficiency of decarburization dramatically increased with increasing decarburization temperature. However,when the annealing temperature was increased to 825°C and 850°C,the steel's carbon content remained essentially unchanged at 0.002%. With increasing decarburization time,the steel's carbon content generally decreased. When both the decarburization temperature and time were increased further,the average grain size dramatically increased and the number of fine grains decreased; meanwhile,some relatively larger grains developed. The main texture types of the decarburized sheets were approximately the same: {001}<110> and {112~115}<110>,with a γ-fiber texture. Furthermore,little change was observed in the texture. Compared with the experimental sheets,the texture of the cold-rolled sheet was very scattered. The best average magnetic induction(B_(800)) among the final products was 1.946 T.展开更多
The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is ...The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is mainly determined by the RC time constant of the catalyst layer and also related with the working electrode potential.展开更多
BACKGROUND The incidence of gastric cancer is high.The number of dissected lymph nodes was an independent factor affecting prognosis.Although preoperative labeling is helpful in lymph nodes resection,there are no guid...BACKGROUND The incidence of gastric cancer is high.The number of dissected lymph nodes was an independent factor affecting prognosis.Although preoperative labeling is helpful in lymph nodes resection,there are no guidelines for when to perform preoperative labeling.AIM To investigate the role of nanocarbon in lymph node dissection during gastrectomy,and to discuss the relationship between the timing of preoperative injection of carbon nanoparticles and the extent of lymph node dissection.METHODS A prospective analysis was performed on the clinical data of 307 patients with advanced gastric cancer who underwent laparoscopic surgery in the General Surgery Department of Weifang People’s Hospital between June 2018 and February 2021.The patients were randomly divided into experimental group and control group based on whether they received preoperative nanocarbon injection or not.The experimental group was divided into different groups according to the preoperative labeling time.The number of dissected lymph nodes and the number of lymph nodes with black staining were compared in each group after surgery,and the role of nanocarbon in the number of dissected lymph nodes,pathological staging,and the relationship with prognosis were discussed.RESULTS The average number of dissected lymph nodes in the experimental group was higher than that in the control group.In the experimental group,the number of lymph node dissections and number of black-staining lymph nodes in the nanocarbon-labeling group at 2 d and 1 d before surgery were higher than in the labeling group on the day before surgery(P<0.05).CONCLUSION Preoperative nanocarbon labeling can safely and effectively guide lymph node dissection.To improve the detection rate of lymph nodes is conducive to subsequent comprehensive anti-tumor therapy.展开更多
Radiogenic carbon (14C) of the DIC (Dissolved Inorganic Carbon) and oxygen-18 were used to understand the hydro- dynamic functioning of the multilayer aquifer system in the Moulares mining basin, southern Tunisia. The...Radiogenic carbon (14C) of the DIC (Dissolved Inorganic Carbon) and oxygen-18 were used to understand the hydro- dynamic functioning of the multilayer aquifer system in the Moulares mining basin, southern Tunisia. The results of this study permits identify two groundwater types. A- an old paleoclimatic groundwater, marked by low carbon-14 (14C) activities. B - a recent groundwater, was distinguished by relatively high carbon-14 activities. In addition to these two water types, other groundwater, indicating a mixing effect, is resulting presumably from upward movement from the deeper groundwater. Based on 14C activity and the piston flow type theory the groundwater residence time varies from 5 Kyear to 35 Kyear. Carbon-14 activity and oxygen-18 in Groundwater are active since Mio-Plio-Quaternary and Upper Cretaceous aquifers lead to the identification of paleorecharged water probably during Late Pleistocene and Early to Middle Holocene. The water feedings of these aquifers are mainly provided by infiltration of precipitations, infiltration of irrigation water, lateral feeding from cretaceous relieves from the South and the North and along recent and fossil drainage networks that constitute major fresh water sources in groundwater tables.展开更多
It is estimated that more than 2.5 billion people worldwide use biomass for cooking. Burning biomass is one of the major contributors to carbon dioxide (CO2) emission—a principle gas in global warming and climate cha...It is estimated that more than 2.5 billion people worldwide use biomass for cooking. Burning biomass is one of the major contributors to carbon dioxide (CO2) emission—a principle gas in global warming and climate change. One way of cutting down the CO2 emissions is adaptation of efficient and clean energy technologies. This study examined the efficiency of the energy saving stoves in Amboseli ecosystem by comparing the cooking time, energy use, wood fuel and carbon emissions to the traditional three stone open fire set ups. The result indicates a statistical difference in the time spent cooking on energy stoves and three stone open fire (t = 5.3055;n = 60;p = 0.00117). Energy saving stoves saved 12.7% - 33.3% of wood fuel compared to the traditional three stones set ups. Water boiling tests to determine the energy savings, revealed that energy saving stoves saved between 25.74% and 26.16% energy/joule per session in-house and outdoor settings respectively. Based on the two meals prepared per day by each household, the total Carbon Emission Savings for the 1000 local beneficiaries of energy saving stoves varied from 102,200 kg CO2 (indoor cooking) to 357,700 kg CO2 (outdoor cooking) per year. It is therefore concluded that energy saving stoves saves time, fuel wood and energy, and reduces carbon emissions. The study findings refute the claims that open fire when carefully operated can be fuel efficient and clean burning to rival energy saving stoves. To improve the performance of the energy saving stoves, it is recommended that a design modification be done to include a chimney to emit excess smoke during indoor cooking;and the stove should be fixed to the floor with mortar to minimise heat loss and breakages.展开更多
The effect of austempering time after the bainitic transformation on the microstructure and property in a low-carbon bainite steel was investigated by metallography and dilatometry. The results showed that by prolongi...The effect of austempering time after the bainitic transformation on the microstructure and property in a low-carbon bainite steel was investigated by metallography and dilatometry. The results showed that by prolonging the austempering time after the bainite transformation, the amount of large-size martensite/austenite islands decreased, but no significant change of the amount and morphology of bainite were observed. In addition, more austenite with a high carbon content was retained by prolonging the holding time at the bainite transformation temperature.Moreover, with a longer holding time, the elongation was improved at the expense of a small decrease in tensile strength. Finally, the Avrami equation B(RF) = 1-exp(-0.0499 × t^0.7616) for bainite reaction at 350℃ was obtained for the tested steel. The work provided a reference for tailoring the properties of low-carbon steels.展开更多
In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts...In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation.展开更多
基金supported by the National Key R&D Program of China(Grant No.2021YFD2200400102)Fujian Provincial Science and Technology Department(Grant No.2021R1002008).
文摘Updating eucalyptus carbon stock data in a timely manner is essential for better understanding and quantifying its effects on ecological and hydrological processes.At present,there are no suitable methods to accurately estimate the eucalyptus carbon stock in a large area.This research aimed to explore the transferability of the eucalyptus carbon stock estimation model at temporal and spatial scales and assess modeling performance through the strategy of combining sample plots,airborne LiDAR and Landsat time series data in subtropical regions of China.Specifically,eucalyptus carbon stock estimates in typical sites were obtained by applying the developed models with the combination of airborne LiDAR and field measurement data;the eucalyptus plantation ages were estimated using the random localization segmentation approach from Landsat time series data;and regional models were developed by linking LiDAR-derived eucalyptus carbon stock and vegetation age(e.g.,months or years).To examine the models’robustness,the developed models at the regional scale were transferred to estimate carbon stocks at the spatial and temporal scales,and the modeling results were evaluated using validation samples accordingly.The results showed that carbon stock can be successfully estimated using the age-based models(both age variables in months and years as predictor variables),but the month-based models produced better estimates with a root mean square error(RMSE)of 6.51 t⋅ha1 for Yunxiao County,Fujian Province,and 6.33 t⋅ha1 for Gaofeng Forest Farm,Guangxi Zhuang Autonomous Region.Particularly,the month-based models were superior for estimating the carbon stocks of young eucalyptus plantations of less than two years.The model transferability analyses showed that the month-based models had higher transferability than the year-based models at the temporal scale,indicating their possibility for analysis of carbon stock change.However,both the month-based and year-based models expressed relatively poor transferability at a spatial scale.This study provides new insights for cost-effective monitoring of carbon stock change in intensively managed plantation forests.
文摘In this study,the effect of decarburization annealing temperature and time on the carbon content,microstructure,and texture of grain-oriented pure iron was investigated by optical microscopy and scanning electron microscopy with electron-backscatter diffraction. The results showed that the efficiency of decarburization dramatically increased with increasing decarburization temperature. However,when the annealing temperature was increased to 825°C and 850°C,the steel's carbon content remained essentially unchanged at 0.002%. With increasing decarburization time,the steel's carbon content generally decreased. When both the decarburization temperature and time were increased further,the average grain size dramatically increased and the number of fine grains decreased; meanwhile,some relatively larger grains developed. The main texture types of the decarburized sheets were approximately the same: {001}<110> and {112~115}<110>,with a γ-fiber texture. Furthermore,little change was observed in the texture. Compared with the experimental sheets,the texture of the cold-rolled sheet was very scattered. The best average magnetic induction(B_(800)) among the final products was 1.946 T.
基金Supported by the National Natural Science Foundation of China(10 7880 2 33)
文摘The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is mainly determined by the RC time constant of the catalyst layer and also related with the working electrode potential.
文摘BACKGROUND The incidence of gastric cancer is high.The number of dissected lymph nodes was an independent factor affecting prognosis.Although preoperative labeling is helpful in lymph nodes resection,there are no guidelines for when to perform preoperative labeling.AIM To investigate the role of nanocarbon in lymph node dissection during gastrectomy,and to discuss the relationship between the timing of preoperative injection of carbon nanoparticles and the extent of lymph node dissection.METHODS A prospective analysis was performed on the clinical data of 307 patients with advanced gastric cancer who underwent laparoscopic surgery in the General Surgery Department of Weifang People’s Hospital between June 2018 and February 2021.The patients were randomly divided into experimental group and control group based on whether they received preoperative nanocarbon injection or not.The experimental group was divided into different groups according to the preoperative labeling time.The number of dissected lymph nodes and the number of lymph nodes with black staining were compared in each group after surgery,and the role of nanocarbon in the number of dissected lymph nodes,pathological staging,and the relationship with prognosis were discussed.RESULTS The average number of dissected lymph nodes in the experimental group was higher than that in the control group.In the experimental group,the number of lymph node dissections and number of black-staining lymph nodes in the nanocarbon-labeling group at 2 d and 1 d before surgery were higher than in the labeling group on the day before surgery(P<0.05).CONCLUSION Preoperative nanocarbon labeling can safely and effectively guide lymph node dissection.To improve the detection rate of lymph nodes is conducive to subsequent comprehensive anti-tumor therapy.
文摘Radiogenic carbon (14C) of the DIC (Dissolved Inorganic Carbon) and oxygen-18 were used to understand the hydro- dynamic functioning of the multilayer aquifer system in the Moulares mining basin, southern Tunisia. The results of this study permits identify two groundwater types. A- an old paleoclimatic groundwater, marked by low carbon-14 (14C) activities. B - a recent groundwater, was distinguished by relatively high carbon-14 activities. In addition to these two water types, other groundwater, indicating a mixing effect, is resulting presumably from upward movement from the deeper groundwater. Based on 14C activity and the piston flow type theory the groundwater residence time varies from 5 Kyear to 35 Kyear. Carbon-14 activity and oxygen-18 in Groundwater are active since Mio-Plio-Quaternary and Upper Cretaceous aquifers lead to the identification of paleorecharged water probably during Late Pleistocene and Early to Middle Holocene. The water feedings of these aquifers are mainly provided by infiltration of precipitations, infiltration of irrigation water, lateral feeding from cretaceous relieves from the South and the North and along recent and fossil drainage networks that constitute major fresh water sources in groundwater tables.
文摘It is estimated that more than 2.5 billion people worldwide use biomass for cooking. Burning biomass is one of the major contributors to carbon dioxide (CO2) emission—a principle gas in global warming and climate change. One way of cutting down the CO2 emissions is adaptation of efficient and clean energy technologies. This study examined the efficiency of the energy saving stoves in Amboseli ecosystem by comparing the cooking time, energy use, wood fuel and carbon emissions to the traditional three stone open fire set ups. The result indicates a statistical difference in the time spent cooking on energy stoves and three stone open fire (t = 5.3055;n = 60;p = 0.00117). Energy saving stoves saved 12.7% - 33.3% of wood fuel compared to the traditional three stones set ups. Water boiling tests to determine the energy savings, revealed that energy saving stoves saved between 25.74% and 26.16% energy/joule per session in-house and outdoor settings respectively. Based on the two meals prepared per day by each household, the total Carbon Emission Savings for the 1000 local beneficiaries of energy saving stoves varied from 102,200 kg CO2 (indoor cooking) to 357,700 kg CO2 (outdoor cooking) per year. It is therefore concluded that energy saving stoves saves time, fuel wood and energy, and reduces carbon emissions. The study findings refute the claims that open fire when carefully operated can be fuel efficient and clean burning to rival energy saving stoves. To improve the performance of the energy saving stoves, it is recommended that a design modification be done to include a chimney to emit excess smoke during indoor cooking;and the stove should be fixed to the floor with mortar to minimise heat loss and breakages.
基金the financial supports from the National Natural Science Foundation of China(NSFC)(Nos.51874216 and 51704217)the Major Projects of Technology Innovation of Hubei Province,China(No.2017AAA116)
文摘The effect of austempering time after the bainitic transformation on the microstructure and property in a low-carbon bainite steel was investigated by metallography and dilatometry. The results showed that by prolonging the austempering time after the bainite transformation, the amount of large-size martensite/austenite islands decreased, but no significant change of the amount and morphology of bainite were observed. In addition, more austenite with a high carbon content was retained by prolonging the holding time at the bainite transformation temperature.Moreover, with a longer holding time, the elongation was improved at the expense of a small decrease in tensile strength. Finally, the Avrami equation B(RF) = 1-exp(-0.0499 × t^0.7616) for bainite reaction at 350℃ was obtained for the tested steel. The work provided a reference for tailoring the properties of low-carbon steels.
基金Sponsored by the "Twelfth Five-year" National Science and Technology Supoort Programe(Grant No.2011BAJ05B02-03)
文摘In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation.