随着对气候变化和粮食安全的的日益认识,低碳农业引起了人们的广泛关注.低碳农业的研究需要综合考虑作物产量和温室气体排放,改进氮肥管理可能有助于减缓作物生产系统的温室气体排放,同时实现对作物稳产甚至高产的需求.本试验利用生命...随着对气候变化和粮食安全的的日益认识,低碳农业引起了人们的广泛关注.低碳农业的研究需要综合考虑作物产量和温室气体排放,改进氮肥管理可能有助于减缓作物生产系统的温室气体排放,同时实现对作物稳产甚至高产的需求.本试验利用生命周期法研究了不同施氮量(150、225、300 kg N·hm^(-2))对春玉米-晚稻轮作系统碳足迹的影响.结果表明:随着氮肥用量增加,两季作物生产过程中温室气体和碳足迹增加.在春玉米生产过程中,氮肥生产和施用引起的温室气体排放对碳足迹贡献最大,占36.2%～50.2%;而在晚稻生产中,甲烷的排放贡献最大,占42.8%～48.0%,并且随氮肥用量增加甲烷排放增加.当氮肥施用量减少25%(225 kg N·hm^(-2))和50%(150 kg N·hm^(-2))时,春玉米生产的温室气体排放分别下降了21.9%和44.3%,碳足迹分别下降了20.3%和39.1%;晚稻生产的温室气体排放分别下降了12.3%和20.4%,碳足迹分别降低了13.7%和16.7%.氮肥减量对春玉米产量无显著影响,而晚稻产量在225 kg N·hm^(-2)施肥量下最高.因此,春玉米氮肥用量降低至150 kg N·hm^(-2)和晚稻氮肥用量降低至225 kg N·hm^(-2)不仅能够保持作物高产,而且还能大幅度降低作物系统的碳足迹.展开更多
After the Industrial Revolution,the ever-increasing atmospheric CO_(2)concentration has resulted in significant problems for human beings.Nearly all countries in the world are actively taking measures to fight for car...After the Industrial Revolution,the ever-increasing atmospheric CO_(2)concentration has resulted in significant problems for human beings.Nearly all countries in the world are actively taking measures to fight for carbon neutrality.In recent years,negative carbon emission technologies have attracted much attention due to their ability to reduce or recycle excess CO_(2)in the atmosphere.This review summarizes the state-of-the-art negative carbon emission technologies,from the artificial enhancement of natural carbon sink technology to the physical,chemical,or biological methods for carbon capture,as well as CO_(2)utilization and conversion.Finally,we expound on the challenges and outlook for improving negative carbon emission technology to accelerate the pace of achieving carbon neutrality.展开更多
Introduction: High-riding nipple following reduction mammoplasty is a challenging problem for the plastic surgeons. To avoid such problem, many methods have been described for marking the correct nipple position but s...Introduction: High-riding nipple following reduction mammoplasty is a challenging problem for the plastic surgeons. To avoid such problem, many methods have been described for marking the correct nipple position but still controversial. We aimed in this study to present our experience in preventing excessive nipple elevation after reduction mammoplasty by using the upper footprint to set the new nipple position. Material and Methods: From March 2019 to March 2022, 25 female patients at a mean age of 38.3 years were included in this prospective study. They underwent reduction mammoplasty with inverted T scar and a combination of inferior pedicle and Würinger’s septum techniques. Resection weights, pre- and postoperative anthropometric measures were recorded. All patients were photographed at the follow-up visits and evaluated for complications if any, the nipple-areola complex (NAC) sensation, and subjective patient satisfaction using “The Breast Evaluation Questionnaire”. Results: The mean preoperative midclavicular point to nipple distance was 37.40 and 37.18 cm for the right and left breasts, respectively. The mean resection weight was 1270 and 1242 g from the right and left sides, respectively. None of our patients experienced NAC necrosis, while 2 breasts had minor wound dehiscence treated conservatively. After a mean follow-up period of 12 months, the NAC descended by an average of 1.40 cm, the distance from the IMF to nipple had an average increase of 2.24 cm, and all of patients were satisfied with the esthetic outcomes and convinced with their breast shape. Conclusion: The upper footprint dependent nipple position seems to have a real role in preventing high-riding nipple after breast reduction in hypertrophic and gigantomastic breasts. Moreover, it can be applied easily and allow for more satisfying outcomes than other methods for setting the new nipple position.展开更多
Hydropower, next to coal, is the second most important source of electric power supply in China. It amounted to 20.4% of the nation＇s total installed capacity of electricity generation in 2011. To provide a comprehen...Hydropower, next to coal, is the second most important source of electric power supply in China. It amounted to 20.4% of the nation＇s total installed capacity of electricity generation in 2011. To provide a comprehensive picture of the development of hydropower in China and its potential environmental impacts, this study calculates the ecological footprint and greenhouse gas emission reduction of hydropower development in China over the past 60 years. The ecological footprints include the energy ecological footprint and arable land occupation footprint. The energy ecological footprint is calculated in terms of the area of the land which would be used for reforestation in order to assimilate CQ emissions from fossil energy consumption for hydropower development. The arable land occupation footprint is calculated in terms of the area of the land to be inundated by hydropower development. The calculated energy ecological footprint was 502 422 ha in 2010 or about 0.3% of total arable land in China and the calculated inundated land was about 1.42×10 6 ha or about 1.2% of total arable land in China. The regional power grid baseline method was used to calculate the greenhouse gas emission reduction. Results indicated that CQ emission reduction from hydropower development was increasing rapidly since 1949 and reached 5.02×108 tons of COe emission in 2010, with an accumulative total of 6.221×109 tons of CQ emission during the period 1949-2010.展开更多
The wobble errors caused by the imperfect integration of motion sensors and transducers in multibeam echo-sounder systems(MBES)manifest as high-frequency wobbles in swaths and hinder the accurate expression of high-re...The wobble errors caused by the imperfect integration of motion sensors and transducers in multibeam echo-sounder systems(MBES)manifest as high-frequency wobbles in swaths and hinder the accurate expression of high-resolution seabed micro-topography under a dynamic marine environment.There are many types of wobble errors with certain coupling among them.However,those current calibration methods ignore the coupling and are mainly manual adjustments.Therefore,we proposed an automatic calibration method with the coupling.First,given the independence of the transmitter and the receiver,the traditional georeferenced model is modified to improve the accuracy of footprint reduction.Secondly,based on the improved georeferenced model,the calibration model associated with motion scale,time delay,yaw misalignment,lever arm errors,and soundings is constructed.Finally,the genetic algorithm(GA)is used to search dynamically for the optimal estimation of the corresponding error parameters to realize the automatic calibration of wobble errors.The simulated data show that the accuracy of the calibrated data can be controlled within 0.2%of the water depth.The measured data show that after calibration,the maximum standard deviation of the depth is reduced by about 5.9%,and the mean standard deviation of the depth is reduced by about 11.2%.The proposed method has significance in the precise calibration of dynamic errors in shallow water multibeam bathymetrie s.展开更多
Inventory analysis of greenhouse gas emission for large-scale biogas plants using carbon footprint method still needs to be improved.Based on the life cycle theory,the application of carbon footprint on four large-sca...Inventory analysis of greenhouse gas emission for large-scale biogas plants using carbon footprint method still needs to be improved.Based on the life cycle theory,the application of carbon footprint on four large-scale biogas plants was analyzed in this paper,which comprehensively considered project progresses of civil engineering construction,operation and comprehensive utilization of residues and slurry.Also the greenhouse gas emissions during the construction and waste removal stages were analyzed and estimated.The carbon footprint of those plants was analyzed in different types and scales.The results showed that the larger scale plant will produce relatively lower carbon footprint.The greenhouse gas emission of energy production,utilization during the period of anaerobic digestion accounted for more than 96%of the entire life cycle emission.The proportion of greenhouse gas emissions on equipment,demolition recycling and transportation phases was smaller,which was less than 1.5%and should be simplified in calculation.The greenhouse gas emission of building materials production can be ignored.展开更多
文摘随着对气候变化和粮食安全的的日益认识,低碳农业引起了人们的广泛关注.低碳农业的研究需要综合考虑作物产量和温室气体排放,改进氮肥管理可能有助于减缓作物生产系统的温室气体排放,同时实现对作物稳产甚至高产的需求.本试验利用生命周期法研究了不同施氮量(150、225、300 kg N·hm^(-2))对春玉米-晚稻轮作系统碳足迹的影响.结果表明:随着氮肥用量增加,两季作物生产过程中温室气体和碳足迹增加.在春玉米生产过程中,氮肥生产和施用引起的温室气体排放对碳足迹贡献最大,占36.2%～50.2%;而在晚稻生产中,甲烷的排放贡献最大,占42.8%～48.0%,并且随氮肥用量增加甲烷排放增加.当氮肥施用量减少25%(225 kg N·hm^(-2))和50%(150 kg N·hm^(-2))时,春玉米生产的温室气体排放分别下降了21.9%和44.3%,碳足迹分别下降了20.3%和39.1%;晚稻生产的温室气体排放分别下降了12.3%和20.4%,碳足迹分别降低了13.7%和16.7%.氮肥减量对春玉米产量无显著影响,而晚稻产量在225 kg N·hm^(-2)施肥量下最高.因此,春玉米氮肥用量降低至150 kg N·hm^(-2)和晚稻氮肥用量降低至225 kg N·hm^(-2)不仅能够保持作物高产,而且还能大幅度降低作物系统的碳足迹.
基金support from National Natural Science Foundation of China(22176086)Natural Science Foundation of Jiangsu Province(BK20210189)+2 种基金State Key Laboratory of Pollution Control and Resource Reuse(PCRR-ZZ-202106)the Fundamental Research Funds for the Central Universities(021114380183,021114380189),China Association for Science and Technology(20220615ZZ08010008)the Research Funds from Frontiers Science Center for Critical Earth Material Cycling of Nanjing University,and Research Funds for Jiangsu Distinguished Professor.H.L.and H.R.would like to acknowledge the support from China Association for Sci-ence and Technology(20220615ZZ08010008).
文摘After the Industrial Revolution,the ever-increasing atmospheric CO_(2)concentration has resulted in significant problems for human beings.Nearly all countries in the world are actively taking measures to fight for carbon neutrality.In recent years,negative carbon emission technologies have attracted much attention due to their ability to reduce or recycle excess CO_(2)in the atmosphere.This review summarizes the state-of-the-art negative carbon emission technologies,from the artificial enhancement of natural carbon sink technology to the physical,chemical,or biological methods for carbon capture,as well as CO_(2)utilization and conversion.Finally,we expound on the challenges and outlook for improving negative carbon emission technology to accelerate the pace of achieving carbon neutrality.
文摘Introduction: High-riding nipple following reduction mammoplasty is a challenging problem for the plastic surgeons. To avoid such problem, many methods have been described for marking the correct nipple position but still controversial. We aimed in this study to present our experience in preventing excessive nipple elevation after reduction mammoplasty by using the upper footprint to set the new nipple position. Material and Methods: From March 2019 to March 2022, 25 female patients at a mean age of 38.3 years were included in this prospective study. They underwent reduction mammoplasty with inverted T scar and a combination of inferior pedicle and Würinger’s septum techniques. Resection weights, pre- and postoperative anthropometric measures were recorded. All patients were photographed at the follow-up visits and evaluated for complications if any, the nipple-areola complex (NAC) sensation, and subjective patient satisfaction using “The Breast Evaluation Questionnaire”. Results: The mean preoperative midclavicular point to nipple distance was 37.40 and 37.18 cm for the right and left breasts, respectively. The mean resection weight was 1270 and 1242 g from the right and left sides, respectively. None of our patients experienced NAC necrosis, while 2 breasts had minor wound dehiscence treated conservatively. After a mean follow-up period of 12 months, the NAC descended by an average of 1.40 cm, the distance from the IMF to nipple had an average increase of 2.24 cm, and all of patients were satisfied with the esthetic outcomes and convinced with their breast shape. Conclusion: The upper footprint dependent nipple position seems to have a real role in preventing high-riding nipple after breast reduction in hypertrophic and gigantomastic breasts. Moreover, it can be applied easily and allow for more satisfying outcomes than other methods for setting the new nipple position.
基金the Key Project for the Strategic Science Plan in Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences(No:2012ZD007)National Natural Science Foundation of China(No.41371486)
文摘Hydropower, next to coal, is the second most important source of electric power supply in China. It amounted to 20.4% of the nation＇s total installed capacity of electricity generation in 2011. To provide a comprehensive picture of the development of hydropower in China and its potential environmental impacts, this study calculates the ecological footprint and greenhouse gas emission reduction of hydropower development in China over the past 60 years. The ecological footprints include the energy ecological footprint and arable land occupation footprint. The energy ecological footprint is calculated in terms of the area of the land which would be used for reforestation in order to assimilate CQ emissions from fossil energy consumption for hydropower development. The arable land occupation footprint is calculated in terms of the area of the land to be inundated by hydropower development. The calculated energy ecological footprint was 502 422 ha in 2010 or about 0.3% of total arable land in China and the calculated inundated land was about 1.42×10 6 ha or about 1.2% of total arable land in China. The regional power grid baseline method was used to calculate the greenhouse gas emission reduction. Results indicated that CQ emission reduction from hydropower development was increasing rapidly since 1949 and reached 5.02×108 tons of COe emission in 2010, with an accumulative total of 6.221×109 tons of CQ emission during the period 1949-2010.
基金Supported by the National Natural Science Foundation of China(Nos.41930535,41830540)the National Key R&D Program of China(No.2018YFC1405900)the SDUST Research Fund(No.2019TDJH103)。
文摘The wobble errors caused by the imperfect integration of motion sensors and transducers in multibeam echo-sounder systems(MBES)manifest as high-frequency wobbles in swaths and hinder the accurate expression of high-resolution seabed micro-topography under a dynamic marine environment.There are many types of wobble errors with certain coupling among them.However,those current calibration methods ignore the coupling and are mainly manual adjustments.Therefore,we proposed an automatic calibration method with the coupling.First,given the independence of the transmitter and the receiver,the traditional georeferenced model is modified to improve the accuracy of footprint reduction.Secondly,based on the improved georeferenced model,the calibration model associated with motion scale,time delay,yaw misalignment,lever arm errors,and soundings is constructed.Finally,the genetic algorithm(GA)is used to search dynamically for the optimal estimation of the corresponding error parameters to realize the automatic calibration of wobble errors.The simulated data show that the accuracy of the calibrated data can be controlled within 0.2%of the water depth.The measured data show that after calibration,the maximum standard deviation of the depth is reduced by about 5.9%,and the mean standard deviation of the depth is reduced by about 11.2%.The proposed method has significance in the precise calibration of dynamic errors in shallow water multibeam bathymetrie s.
基金China National‘The Twelfth Five-Year Plan’for Science&Technology Supporting Project(Grant No.2012BAD47B03)Key Project for Agriculture Transformation of Scientific and Technological Achievements from the Ministry of Science and Technology of China(No.2014GB2A400088,“Technical Transformation and Demonstration Project of High Efficiency Anaerobic Biogas Production in Breeding Farm of Dry Dejecta Collection Mode”)and Beijing Municipal Key Discipline of Biomass Engineering.
文摘Inventory analysis of greenhouse gas emission for large-scale biogas plants using carbon footprint method still needs to be improved.Based on the life cycle theory,the application of carbon footprint on four large-scale biogas plants was analyzed in this paper,which comprehensively considered project progresses of civil engineering construction,operation and comprehensive utilization of residues and slurry.Also the greenhouse gas emissions during the construction and waste removal stages were analyzed and estimated.The carbon footprint of those plants was analyzed in different types and scales.The results showed that the larger scale plant will produce relatively lower carbon footprint.The greenhouse gas emission of energy production,utilization during the period of anaerobic digestion accounted for more than 96%of the entire life cycle emission.The proportion of greenhouse gas emissions on equipment,demolition recycling and transportation phases was smaller,which was less than 1.5%and should be simplified in calculation.The greenhouse gas emission of building materials production can be ignored.
