为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260...为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260全秸秆茬地洁区旋耕智能施肥播种机和3ZF-4(200)中耕追肥机,设置7种施肥模式(30 cm+15 cm宽窄行种植):以尿素4次分施(N 240 kg hm^(-2),基肥∶分蘖肥∶拔节肥∶孕穗肥=5∶1∶2∶2,窄行基施,追肥全田撒施)为对照(CK);减氮15%(N 204 kg hm^(-2))条件下设置6种处理:M_(1)(100%SRF窄行基施);M_(2)(60%SRF窄行基施+40%U拔节期窄行撒施);M_(3)(60%SRF窄行基施+40%U返青期宽行条施);M_(4)(60%SRF窄行基施+40%SRF返青期窄行撒施);M_(5)(60%SRF窄行基施+40%SRF返青期宽行条施);M_(4+5)(60%SRF窄行基施+20%SRF返青期宽行条施+20%SRF返青期窄行撒施)。研究比较不同施肥模式对小麦产量效益、根系形态生理、氮素利用效率及N_(2)O排放的影响。结果表明,与CK相比,M_(2)~M_(5)处理提高了小麦产量(4.0%~19.0%)和经济效益(13.7%~35.7%),其中M_(4)和M_(5)处理表现最优,分别增产14.1%和19.0%,经济效益提升34.5%和35.7%。这些处理明显改善了根系特性(根干重密度增加9.7%~111.8%,根系活力和氧化力分别提高6.8%~52.0%和4.2%~44.2%),降低N_(2)O累积排放量22.6%~34.5%,提高0~20 cm土层硝态氮含量11.2%~40.0%。在氮素利用方面,M_(2)~M_(5)处理均提高了籽粒氮素积累量、花后氮素积累量及其对籽粒氮素的贡献率,氮肥利用效率指标(包括偏生产力、农学效率和表观利用率)分别显著提升了22.4%~40.0%、29.7%~74.3%和9.41~18.77个百分点。值得注意的是,M_(4)和M_(5)处理表现出最优的综合效益:N_(2)O累积排放量降幅最大(分别达27.0%和34.5%),氮肥表观利用率2季均维持在43.0%以上(均值分别为43.5%和46.8%),同时在生育后期保持较高的根系活性和耕层无机氮含量。相比之下,M_(1)处理虽然实现了最大的N_(2)O减排效果(降幅35.9%),但导致减产10.4%和经济效益下降10.8%,且氮肥利用效率呈现不稳定的年际变化特征。而优化处理M_(4+5)进一步改善了根系形态生理特性,并提高氮肥表观利用率和籽粒氮素积累量。综上,减氮15%条件下(N 204 kg hm^(-2)),缓混肥2次施用处理(M_(4)和M_(5))能实现产量、经济效益、氮肥利用效率和N_(2)O减排的协同提高,并以追肥深施处理(M_(5))效应更强。本研究为稻茬小麦缓释肥减氮优化高效应用提供重要理论依据。展开更多
The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the ...The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the reduction of greenhouse gas CO_(2)emissions could be achieved.However,the targeted breaking of the C-C/C-H bonds of ethane is still a challenge for the designed catalysts.In this paper,ZnO-doped ZrO_(2)bifunctional catalysts(Zn_(x)ZrO)with different Zn/Zr molar ratios were prepared by the deposition-precipitation method,and the functions of various sites for CO_(2)-ODHE reaction were revealed by in situ characterizations and ethane pulse experiment:the medium-strength acidic Zn-O-Zr sites are responsible for the purposefully cracking of ethane C-H bonds to ethylene,while the more oxygen vacancies(OV)created by the introduction of Zn^(2+)are responsible for the efficient activation C=O bonds of CO_(2),thus promoting the RWGS reaction.In addition,the Zn0.2ZrO catalyst demonstrated excellent catalytic performances,with C_(2)H_(6)conversion,C_(2)H_(4)yield,and CO_(2)conversion about 19.1%,10.5%,and 10.6%within 5 h,respectively(600℃,GHSV=3000 mL/(g·h)).Especially,the initial ethylene space-time yield of 355.5μmol/(min·g)was obtained under 6000 mL/(g·h);Finally,the tandem reaction mechanism of ethane dehydrogenation and RWGS was revealed.展开更多
Ternary blending as one of the most successful strategies has achieved continuous performance breakthroughs in organic solar cells(OSCs)over the past few years.Here,a small molecule featuring a dithieno[3,2-f:2′,3′-...Ternary blending as one of the most successful strategies has achieved continuous performance breakthroughs in organic solar cells(OSCs)over the past few years.Here,a small molecule featuring a dithieno[3,2-f:2′,3′-h]phthalimide derivative as the intermediate unit,named DTP-C8-R,is designed and utilized as the third component to construct ternary OSCs(TOSCs).The increased molecular packing of L8-BO as well as the charge transfer excitons between PM6 and DTP-C8-R lead to a very low nonradiative energy loss of 0.179 eV and a high open-circuit voltage(V_(OC))of 0.910 V in the TOSCs based on the PM6:L8-BO host blend.Moreover,the DTP-C8-R:PM6:L8-BO film(0.05:0.95:1.2,w/w)possesses better fibrous nanophase separation and the enhancedπ-πstacking ordering of the acceptors with a larger crystal coherence length compared with the PM6:L8-BO blend film,so the TOSCs present more efficient exciton dissociation,longer carrier lifetime,faster carrier transport and less charge recombination.It boosts the power conversion efficiency to 19.22%with a short-circuit current density of 27.10 mA cm^(-2).This work demonstrates that the small molecule based on a dithieno[3,2-f:2′,3′-h]phthalimide derivative as the minor component is an executable strategy to achieve high-performance TOSCs with high V_(OC).展开更多
文摘为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260全秸秆茬地洁区旋耕智能施肥播种机和3ZF-4(200)中耕追肥机,设置7种施肥模式(30 cm+15 cm宽窄行种植):以尿素4次分施(N 240 kg hm^(-2),基肥∶分蘖肥∶拔节肥∶孕穗肥=5∶1∶2∶2,窄行基施,追肥全田撒施)为对照(CK);减氮15%(N 204 kg hm^(-2))条件下设置6种处理:M_(1)(100%SRF窄行基施);M_(2)(60%SRF窄行基施+40%U拔节期窄行撒施);M_(3)(60%SRF窄行基施+40%U返青期宽行条施);M_(4)(60%SRF窄行基施+40%SRF返青期窄行撒施);M_(5)(60%SRF窄行基施+40%SRF返青期宽行条施);M_(4+5)(60%SRF窄行基施+20%SRF返青期宽行条施+20%SRF返青期窄行撒施)。研究比较不同施肥模式对小麦产量效益、根系形态生理、氮素利用效率及N_(2)O排放的影响。结果表明,与CK相比,M_(2)~M_(5)处理提高了小麦产量(4.0%~19.0%)和经济效益(13.7%~35.7%),其中M_(4)和M_(5)处理表现最优,分别增产14.1%和19.0%,经济效益提升34.5%和35.7%。这些处理明显改善了根系特性(根干重密度增加9.7%~111.8%,根系活力和氧化力分别提高6.8%~52.0%和4.2%~44.2%),降低N_(2)O累积排放量22.6%~34.5%,提高0~20 cm土层硝态氮含量11.2%~40.0%。在氮素利用方面,M_(2)~M_(5)处理均提高了籽粒氮素积累量、花后氮素积累量及其对籽粒氮素的贡献率,氮肥利用效率指标(包括偏生产力、农学效率和表观利用率)分别显著提升了22.4%~40.0%、29.7%~74.3%和9.41~18.77个百分点。值得注意的是,M_(4)和M_(5)处理表现出最优的综合效益:N_(2)O累积排放量降幅最大(分别达27.0%和34.5%),氮肥表观利用率2季均维持在43.0%以上(均值分别为43.5%和46.8%),同时在生育后期保持较高的根系活性和耕层无机氮含量。相比之下,M_(1)处理虽然实现了最大的N_(2)O减排效果(降幅35.9%),但导致减产10.4%和经济效益下降10.8%,且氮肥利用效率呈现不稳定的年际变化特征。而优化处理M_(4+5)进一步改善了根系形态生理特性,并提高氮肥表观利用率和籽粒氮素积累量。综上,减氮15%条件下(N 204 kg hm^(-2)),缓混肥2次施用处理(M_(4)和M_(5))能实现产量、经济效益、氮肥利用效率和N_(2)O减排的协同提高,并以追肥深施处理(M_(5))效应更强。本研究为稻茬小麦缓释肥减氮优化高效应用提供重要理论依据。
文摘The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the reduction of greenhouse gas CO_(2)emissions could be achieved.However,the targeted breaking of the C-C/C-H bonds of ethane is still a challenge for the designed catalysts.In this paper,ZnO-doped ZrO_(2)bifunctional catalysts(Zn_(x)ZrO)with different Zn/Zr molar ratios were prepared by the deposition-precipitation method,and the functions of various sites for CO_(2)-ODHE reaction were revealed by in situ characterizations and ethane pulse experiment:the medium-strength acidic Zn-O-Zr sites are responsible for the purposefully cracking of ethane C-H bonds to ethylene,while the more oxygen vacancies(OV)created by the introduction of Zn^(2+)are responsible for the efficient activation C=O bonds of CO_(2),thus promoting the RWGS reaction.In addition,the Zn0.2ZrO catalyst demonstrated excellent catalytic performances,with C_(2)H_(6)conversion,C_(2)H_(4)yield,and CO_(2)conversion about 19.1%,10.5%,and 10.6%within 5 h,respectively(600℃,GHSV=3000 mL/(g·h)).Especially,the initial ethylene space-time yield of 355.5μmol/(min·g)was obtained under 6000 mL/(g·h);Finally,the tandem reaction mechanism of ethane dehydrogenation and RWGS was revealed.
基金financially supported by the National Natural Science Foundation of China(51873177,52303252)the Natural Science Foundation of Hunan Province(2024JJ4039)+1 种基金the Advanced Photoelectricity and Supramolecular Functional Materials of the Ministry of Education(IRT-17R90)the Hunan 2011 Collaborative Innovation Centre of Chemical Engineering&Technology with Environmental Benignity and Effective Resource Utilization。
文摘Ternary blending as one of the most successful strategies has achieved continuous performance breakthroughs in organic solar cells(OSCs)over the past few years.Here,a small molecule featuring a dithieno[3,2-f:2′,3′-h]phthalimide derivative as the intermediate unit,named DTP-C8-R,is designed and utilized as the third component to construct ternary OSCs(TOSCs).The increased molecular packing of L8-BO as well as the charge transfer excitons between PM6 and DTP-C8-R lead to a very low nonradiative energy loss of 0.179 eV and a high open-circuit voltage(V_(OC))of 0.910 V in the TOSCs based on the PM6:L8-BO host blend.Moreover,the DTP-C8-R:PM6:L8-BO film(0.05:0.95:1.2,w/w)possesses better fibrous nanophase separation and the enhancedπ-πstacking ordering of the acceptors with a larger crystal coherence length compared with the PM6:L8-BO blend film,so the TOSCs present more efficient exciton dissociation,longer carrier lifetime,faster carrier transport and less charge recombination.It boosts the power conversion efficiency to 19.22%with a short-circuit current density of 27.10 mA cm^(-2).This work demonstrates that the small molecule based on a dithieno[3,2-f:2′,3′-h]phthalimide derivative as the minor component is an executable strategy to achieve high-performance TOSCs with high V_(OC).