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4-异丙基苯硼酸产率构成因素的灰色关联度分析
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作者 张永强 邓燕 +1 位作者 张华美 贺全国 《化学工业与工程》 CAS 2007年第4期370-372,共3页
应用灰色系统理论中的关联度分析法对4-异丙基苯硼酸的产率构成因素进行了关联度分析。结果表明:4-异丙基苯硼酸的产率构成因素对产率影响大小的顺序为反应物比例>滴加时间>温度,且亲核取代温度较高时,可以适当增加反应物比例或... 应用灰色系统理论中的关联度分析法对4-异丙基苯硼酸的产率构成因素进行了关联度分析。结果表明:4-异丙基苯硼酸的产率构成因素对产率影响大小的顺序为反应物比例>滴加时间>温度,且亲核取代温度较高时,可以适当增加反应物比例或延长滴加时间,同样可以获得较高的产率,得出了4-异丙基苯硼酸的优化合成条件。 展开更多
关键词 4-异丙基苯硼酸 合成 产率构成因素 灰色关联度分析
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Release Characteristics of Release-controlled Nitrogen Fertilizer in Winter Wheat on Dry Land
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作者 牟小翎 于淑慧 +3 位作者 董浩 毕军 朱国梁 陈靖 《Agricultural Science & Technology》 CAS 2017年第7期1308-1311,共4页
[Objective] The aim was to study the release characteristics of different release-controlled fertilizers, as well as their effects on wheat growth and develop- ment under water stress. [method] With phosphorus-potassi... [Objective] The aim was to study the release characteristics of different release-controlled fertilizers, as well as their effects on wheat growth and develop- ment under water stress. [method] With phosphorus-potassium fertilization and opti- mized fertilization (OPT) as the control, the release characteristics of 4 kinds of re- lease-controlled nitrogen fertilizers (A, B, C and D) coated with different materials were studied. [Result] Under the same phosphorus and potassium levels, the re- lease-controlled nitrogen fertilizers A and B significantly improved the yield of wheat. Spike number is the main reason leading to the difference in yield. The fertilizers A and B were released by 44.4% and 46.3% before winter, released by 72.1% and 69.8% at the jointing stage, and related by 88.0% and 91.5% in the harvest period, meeting the nitrogen requirement of dryland wheat across the growth period. Com- pared with OPT, the nitrogen accumulation amounts in treatments A and B were increased by 1.39 and 2.09 kg/667 m2, the nitrogen use efficiencies were increased by 8.66% and 13.04%, and the nitrogen partial factor productivities were increased by 9.00 and 7.22 kg/kg, respectively. [Conclusion] Among the 4 kinds of fertilizers, A and B were considered as the optimum release-controlled nitrogen fertilizers for winter wheat on dry land. 展开更多
关键词 Dryland wheat Release-controlled fertilizer YIELD Yield composition Ni- trogen use efficiency
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Supplementary Irrigation and Soil Amendment Management with Sorghum on Khor Abu Habil (Sudan)
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作者 M.A. Omer E.M. Alamin 《Journal of Environmental Science and Engineering》 2011年第8期1079-1083,共5页
This research was conducted for 3 cropping seasons at Elobeid Research Station in Western Sudan. The objectives were to improve the irrigation water and soil management and crop yield by evaluating the response of sor... This research was conducted for 3 cropping seasons at Elobeid Research Station in Western Sudan. The objectives were to improve the irrigation water and soil management and crop yield by evaluating the response of sorghum crop to different supplementary irrigation regimes and soil amendments management in flood basin irrigated scheme. The existing flood irrigation practice was basically conducive to late planting, weed growth, late season water stress and pest and diseases attack. Four levels of each irrigation regimes and farm yard manure (FYM) treatments arranged in split-plot design were tested. Rainfall, field capacity, irrigation water added, profile water content, plant height, yield components and water use efficiency were measured. Grain yield was significantly increased (p 〈 0,01) with irrigation treatments where 1919, 1870 and 878 kg/ha were obtained for one, two and no irrigation treatments, respectively. The 3 irrigations treatment has produced relatively lower grain yield (1679 kg/ha). FYM treatment up to 4-8 t/ha showed increase in grain yield. Water added in 1, 2 and 3 irrigation treatments amounts to 4475, 5302 and 6035 m3/ha, respectively which supplmented the rainfall by 23%, 45% and 65%, respectively. Water use efficiency was greater with 1 and 2 irrigation treatments and 4 t/ha FYM which reached 0.43, 0.35 and 0.28 kg/m3, respectively. The result concludes that providing supplementary irrigation from crop establishment to mid season was found sufficient to improve crop productivity. 展开更多
关键词 Supplementary irrigation SORGHUM water stress
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Effects of Plant Population on Growth, Development and Oil Yield of Safflower
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作者 Vallantino Emongor Otsoseng Oagile Boipuso Kedikanetswe 《Journal of Agricultural Science and Technology(B)》 2013年第5期321-333,共13页
Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects ... Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects on growth, development, yield components, yield and oil content of safflower. Increasing safflower plant density from 100,000 to 250,000 plants ha^- significantly reduced plant height (13.2%-21.3%), branch number plant^-1 (37%-54.7%), leaf number plant^-1 (39%-39.2%), leaf area (19.5%-53%), plant spread (39.6%-54.4%), root length (28.1%-54.4%), plant biomass (17%-50%), capitula size (12%-12.7%), capitula number plant^-1 (39.5%-50.5%), seed number capitula~ (39%-45%), capitula weight (3.3%-3.6%), seed yield (67.9%-69.8%) and seed oil content (14.7%-20.8%). The reduction in vegetative growth, yield components, yield and oil content of safflower due to increased plant density was attributed to inter and intra-plant competition for light, nutrients and water necessary for growth and development. The differences between winter and summer grown safflower were attributed to difference in day and night temperature (DIF) and the average daily temperature which were optimum for safflower growth in winter. It was concluded that under Botswana conditions or in semi-arid areas, safflower should be planted at 50 cm × 20 cm or wider in order to maximize yield and oil content and allow the plants to express their maximum genetic potential. 展开更多
关键词 Safflower (Carthamus tinctorius L.) plant density vegetative growth yield and yield components oil content.
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Relationships Between Yield, Quality and Nitrogen Uptake and Utilization of Organically Grown Rice Varieties 被引量:11
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作者 HUANG Lifen YU Jun +4 位作者 YANG Jie ZHANG Rong BAI Yanchao SUN Chengming ZHUANG Hengyang 《Pedosphere》 SCIE CAS CSCD 2016年第1期85-97,共13页
Due to the relatively late start of organic rice(Oryza sativa L.) research in China,there is a still lack of systematic research on rice varieties,organic fertilizer management practices,and especially the mechanisms ... Due to the relatively late start of organic rice(Oryza sativa L.) research in China,there is a still lack of systematic research on rice varieties,organic fertilizer management practices,and especially the mechanisms of nitrogen(N) uptake and utilization.Three rice varieties,Nanjing 5055,Nanjing 9108,and Nanjing 46,were grown under organic farming(OF) at three organic fertilizer levels(103.2,160.8,and 218.4 kg N ha^(-1)) and conventional farming(CF) with regular chemical fertilizers.Rice grain yields,yield components,and quality,dry matter accumulation,and plant N were measured at different growth stages during the 2012 and 2013 growing seasons.Compared with CF,OF had a significantly reduced yield.Nanjing 9108 showed significant reductions in number of panicles per unit area and percentage of filled grains,and had the lowest yield.The effects of fertilizer type and application rate on dry matter accumulation during the main growth periods were significant for all varieties.The N content and uptake in organically grown rice were lower compared with those of rice under CF.The N recovery efficiency and N agronomic efficiency were significantly lower,whereas N physiological efficiency and N partial factor productivity were greater under OF than under CF.Under OF,the processing quality showed a slight but insignificant decline,protein content and gel consistency increased,and amylose content decreased compared with those under CF.Correlation analysis showed that under OF,grain yield was significantly correlated with N uptake.The medium organic fertilizer level(160.8 kg N ha^(-1)) was found to be the optimum fertilizer treatment,and Nanjing 46 appeared to be the best variety for organic rice cultivation.To increase rice grain yields and reduce the potential risk of non-point source pollution in organic agriculture,further research is needed to improve the N use efficiency in organic rice cultivation. 展开更多
关键词 conventional farming grain quality grain yield N use efficiency organic farming organic fertilizer
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