为探究不同稻-鸭-虾种养模式与水稻单作模式和传统稻-虾种养模式的碳排放及碳固定特征差异,于湖北省荆州市华中农业大学双水双绿研究基地开展大田试验,以水稻品种华墨香5号、克氏原螯虾(Procambarus clarki)、肉鸭武禽10号为试验材料,...为探究不同稻-鸭-虾种养模式与水稻单作模式和传统稻-虾种养模式的碳排放及碳固定特征差异,于湖北省荆州市华中农业大学双水双绿研究基地开展大田试验,以水稻品种华墨香5号、克氏原螯虾(Procambarus clarki)、肉鸭武禽10号为试验材料,研究水稻单作(monoculture,CK1)模式、稻-虾种植(rice-crayfish coculture,CK2)、稻-鸭-虾单元格投放(rice-duck-crayfish unit release model,CRXD)、稻-鸭-虾“游牧鸭”(rice-duckcrayfish“nomadic duck”model,NRXD)、稻-鸭-虾大田块(rice-duck-crayfish large field block model,BRXD)共5种养模式下稻田甲烷(methane,CH4)、氧化亚氮(nitrous oxide,N2O)排放、全球增温潜势(global warming potential,GWP)、温室气体排放强度(greenhouse gas emission intensity,GHGI)以及碳固定潜力。结果显示,相比传统水稻单作模式,稻-鸭-虾模式降低了稻田CH4排放、GWP、GHGI,碳中和效应显著增加。与水稻单作相比,稻-鸭-虾模式CH4的排放量降低了28.1%~32.1%,GWP降低了27.0%~30.7%,GHGI降低了23.0%~26.7%,碳固定增加了2089~2569 kg/hm^(2)。与稻-虾种养相比,稻-鸭-虾模式的CH4排放量降低了18.6%~23.1%,GWP降低了17.9%~22.2%,GHGI下降18.7%~22.0%,碳固定增加了616~1096 kg/hm^(2)。结果表明,稻-鸭-虾模式可以降低稻田碳排放量,提高稻田碳中和潜力,其中稻-鸭-虾大田块模式固碳减排效果最佳。展开更多
High purity magnesium is not only an important basic raw material for semiconductor and electronics industries,but also a promising new generation of electrochemical energy storage materials and biomedical materials.I...High purity magnesium is not only an important basic raw material for semiconductor and electronics industries,but also a promising new generation of electrochemical energy storage materials and biomedical materials.Impurities in high-purity magnesium affect material properties,which has become the most critical factor restricting its application.However,accurate analysis of multiple ultra-trace impurity elements in high-purity magnesium is extremely challenging.In this paper,based on the synergistic effect of N_(2)O/H_(2) reaction gas mixture to eliminate spectral interference of inductively coupled plasma tandem mass spectrometry(ICP-MS/MS),a new strategy for the quantification of 45 ultra-trace impurity elements in high-purity magnesium was proposed.The results indicated that the limits of detection(LOD)were in the range of 0.02–18.5 ng L^(−1);the LODs of the challenging non-metallic elements Si and S were 18.5 and 12.2 ng L^(−1),respectively;and the LODs of all the other analytes were less than 10 ng L^(−1).Even under hot plasma conditions,LODs of alkali metal elements were also less than 5 ng L^(−1).The spike recovery of each analyte was 93.6%–107%,and the relative standard deviation(RSD)was 3.2%–6.9%,respectively.At a 95%level of confidence,no significant differences were found between the results obtained under the optimal conditions for the analyte with the developed method and the measurement results of SF-ICP-MS.The developed method indicated low LOD,high sample throughput,and complete interference elimination,demonstrating a new avenue for the rapid determination of ultra-trace elements in high-purity magnesium.展开更多
The present paper reported the structural and luminescent properties of Eu^（2＋） and Nd^（3＋） doped CaAl_2O_4 phosphor. The samples were prepared by microwave-assisted chemical co-precipitation（MA-CCP）, a synthe...The present paper reported the structural and luminescent properties of Eu^（2＋） and Nd^（3＋） doped CaAl_2O_4 phosphor. The samples were prepared by microwave-assisted chemical co-precipitation（MA-CCP）, a synthesis technique which is suitable for small and uniform particle that could be used directly without grinding. The effects of different microwave temperatures on structure and photoluminescence behavior were studied. Formation of a phosphor and phase purity were confirmed by X-ray diffraction technique（XRD） with variable microwave temperatures. XRD analysis showed that the phosphors prepared by MA-CCP method at the temperature of 750, 900oC, respectively and solid-state reaction（SSR） method at 1300oC consisted of impurities. Commission Internationale de L＇Eclairage（CIE） color coordinates of CaAl_2O_4：Eu^（2＋）,Nd^（3＋） were suitable as blue light emitting phosphor. Excitation and emission peaks of the samples prepared by different methods in this study were almost the same. The images of SEM showed that the size of the phosphors prepared by MA-CCP method reached a submicrometer.展开更多
文摘为探究不同稻-鸭-虾种养模式与水稻单作模式和传统稻-虾种养模式的碳排放及碳固定特征差异,于湖北省荆州市华中农业大学双水双绿研究基地开展大田试验,以水稻品种华墨香5号、克氏原螯虾(Procambarus clarki)、肉鸭武禽10号为试验材料,研究水稻单作(monoculture,CK1)模式、稻-虾种植(rice-crayfish coculture,CK2)、稻-鸭-虾单元格投放(rice-duck-crayfish unit release model,CRXD)、稻-鸭-虾“游牧鸭”(rice-duckcrayfish“nomadic duck”model,NRXD)、稻-鸭-虾大田块(rice-duck-crayfish large field block model,BRXD)共5种养模式下稻田甲烷(methane,CH4)、氧化亚氮(nitrous oxide,N2O)排放、全球增温潜势(global warming potential,GWP)、温室气体排放强度(greenhouse gas emission intensity,GHGI)以及碳固定潜力。结果显示,相比传统水稻单作模式,稻-鸭-虾模式降低了稻田CH4排放、GWP、GHGI,碳中和效应显著增加。与水稻单作相比,稻-鸭-虾模式CH4的排放量降低了28.1%~32.1%,GWP降低了27.0%~30.7%,GHGI降低了23.0%~26.7%,碳固定增加了2089~2569 kg/hm^(2)。与稻-虾种养相比,稻-鸭-虾模式的CH4排放量降低了18.6%~23.1%,GWP降低了17.9%~22.2%,GHGI下降18.7%~22.0%,碳固定增加了616~1096 kg/hm^(2)。结果表明,稻-鸭-虾模式可以降低稻田碳排放量,提高稻田碳中和潜力,其中稻-鸭-虾大田块模式固碳减排效果最佳。
基金supported by the Natural Science Foundation of China(52171103 and 21975289).
文摘High purity magnesium is not only an important basic raw material for semiconductor and electronics industries,but also a promising new generation of electrochemical energy storage materials and biomedical materials.Impurities in high-purity magnesium affect material properties,which has become the most critical factor restricting its application.However,accurate analysis of multiple ultra-trace impurity elements in high-purity magnesium is extremely challenging.In this paper,based on the synergistic effect of N_(2)O/H_(2) reaction gas mixture to eliminate spectral interference of inductively coupled plasma tandem mass spectrometry(ICP-MS/MS),a new strategy for the quantification of 45 ultra-trace impurity elements in high-purity magnesium was proposed.The results indicated that the limits of detection(LOD)were in the range of 0.02–18.5 ng L^(−1);the LODs of the challenging non-metallic elements Si and S were 18.5 and 12.2 ng L^(−1),respectively;and the LODs of all the other analytes were less than 10 ng L^(−1).Even under hot plasma conditions,LODs of alkali metal elements were also less than 5 ng L^(−1).The spike recovery of each analyte was 93.6%–107%,and the relative standard deviation(RSD)was 3.2%–6.9%,respectively.At a 95%level of confidence,no significant differences were found between the results obtained under the optimal conditions for the analyte with the developed method and the measurement results of SF-ICP-MS.The developed method indicated low LOD,high sample throughput,and complete interference elimination,demonstrating a new avenue for the rapid determination of ultra-trace elements in high-purity magnesium.
基金Project supported by the Fundamental Research Funds for the Central Universities(JUSRP51723B)National Natural Science Foundation of China(51503083)+2 种基金Jiangsu Province Ordinary University Academic Degree Graduate Student Scientific Research Innovation Projects(KYLX16_0798)the Priority Academic Program Development of Jiangsu Higher Education InstitutionsProduction,Education&Research Cooperative Innovation Fund Project of Jiangsu Province(BY2015057-23)
文摘The present paper reported the structural and luminescent properties of Eu^（2＋） and Nd^（3＋） doped CaAl_2O_4 phosphor. The samples were prepared by microwave-assisted chemical co-precipitation（MA-CCP）, a synthesis technique which is suitable for small and uniform particle that could be used directly without grinding. The effects of different microwave temperatures on structure and photoluminescence behavior were studied. Formation of a phosphor and phase purity were confirmed by X-ray diffraction technique（XRD） with variable microwave temperatures. XRD analysis showed that the phosphors prepared by MA-CCP method at the temperature of 750, 900oC, respectively and solid-state reaction（SSR） method at 1300oC consisted of impurities. Commission Internationale de L＇Eclairage（CIE） color coordinates of CaAl_2O_4：Eu^（2＋）,Nd^（3＋） were suitable as blue light emitting phosphor. Excitation and emission peaks of the samples prepared by different methods in this study were almost the same. The images of SEM showed that the size of the phosphors prepared by MA-CCP method reached a submicrometer.
