期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
覆盖对水稻田温室气体排放效应的影响 被引量:3
1
作者 王雅霏 杨喜爱 +3 位作者 潘婷 高峰峰 江先民 银敏华 《作物研究》 2022年第1期1-8,共8页
农田覆盖作为一种重要的农艺生产措施,已被广泛应用于各种农业生产活动中。为了定量分析覆盖条件下农田温室气体的排放效应、改善农田覆盖模式和减少农业温室气体排放,采用Meta分析方法分析了覆盖对水稻田温室气体排放的影响,并对其主... 农田覆盖作为一种重要的农艺生产措施,已被广泛应用于各种农业生产活动中。为了定量分析覆盖条件下农田温室气体的排放效应、改善农田覆盖模式和减少农业温室气体排放,采用Meta分析方法分析了覆盖对水稻田温室气体排放的影响,并对其主要影响因素进行解析。结果表明,与不覆盖相比,覆盖水稻田CO_(2)排放量平均增加21.9%(置信区间2.6%~44.8%),N_(2)O排放量平均减少43.9%(置信区间32.3%~53.5%),CH_(4)排放量平均减少58.5%(置信区间50.8%~65.0%)。N_(2)O排放量随施氮量的增加呈降低趋势,覆盖水稻田的平均减排率为湖南和江苏高于重庆和湖北;与一次性基施、地膜覆盖、部分地面覆盖、垄作和连作相比,基肥+追肥、秸秆覆盖、全地面覆盖、平作和轮作更有利于提高覆盖水稻田的N_(2)O减排率。CH_(4)排放量随施氮量的增加呈增加趋势,覆盖水稻田的平均减排率表现为四川>江苏>湖北>湖南>重庆;与基肥+追肥、秸秆覆盖、全地面覆盖、垄作和轮作相比,一次性基施、地膜覆盖、部分地面覆盖、平作和连作更有利于提高覆盖水稻田的CH_(4)减排率。 展开更多
关键词 稻田 覆盖 温室气体 排放
在线阅读 下载PDF
Synthesis of comb bipolymers and their pour point depressing properties
2
作者 Zhang Changqiao gao Congcong +4 位作者 gao fengfeng Wang Jian Zhang Dawei Wang Yan Xu Dawei 《Petroleum Science》 SCIE CAS CSCD 2014年第1期155-160,共6页
A bipolymer maleic anhydride-methyl acrylate (MAMA) was synthesized from maleic anhydride and methyl acrylate based on molecular design.MAMA further reacted with oleylamine or octadecyl alcohol to generate two comb ... A bipolymer maleic anhydride-methyl acrylate (MAMA) was synthesized from maleic anhydride and methyl acrylate based on molecular design.MAMA further reacted with oleylamine or octadecyl alcohol to generate two comb polymers called Oleamide-MAMA (NMAMA) and OctadecanolMAMA (OMAMA),respectively.The structure of both the polymers was confirmed by their infrared spectral analysis (IR),gel permeation chromatography analysis (GPC) and differential scanning calorimeter (DSC).Moreover,the pour point depressing (PPD) properties of these comb polymers were examined experimentally.Experimental results showed that besides the molecular weight and concentration of the polymers,the length of side chains and the number of functional groups also had great influence on the pour point depressing performance.The π bonds and hydrogen bonds between depressants were the key factors for improving the pour point depressing properties.These results suggest that both OMAMA and NMAMA are potential pour point depressants for industry. 展开更多
关键词 Maleic anhydride comb polymers pour point depressant hydrogen bonds molecular simulation
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部