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Effect of Tillage Methods and Foliar Fertilization (<i>Boost Extra</i><sup>TM</sup>) on Soil Physical Properties, Weed Dry Matter and Grain Yield of Sorghum in Ejiba, Kogi State, Nigeria
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作者 S. K. Ogundare M. O. Aduloju +1 位作者 F. G. Ayodele S. D. Olorunfemi 《Natural Science》 2015年第6期338-345,共8页
An experiment was carried out for two consecutive growing seasons (2012 and 2013) at the Research Site of the Lower Niger River Basin Development Authority, Ejiba, Nigeria, to examine the response of sorghum to tillag... An experiment was carried out for two consecutive growing seasons (2012 and 2013) at the Research Site of the Lower Niger River Basin Development Authority, Ejiba, Nigeria, to examine the response of sorghum to tillage methods and foliar fertilizer (Boost ExtraTM) application. A split plot experiment was laid out in a Randomized Complete Block Design (RCBD) with three replicates to randomize the tillage methods (main plots) and foliar fertilizer application (sub-plots), respectively. The experiment comprised of three tillage methods: No Tillage (NT), Manual Tillage (MT) and convectional tillage (Ploughing, Harrowing and Ridging, PHR) and three foliar fertilizer rates: 0, 2 and 4 liters of foliar fertilizer per hectare. The parameters taken on soil physical properties and weed characters are soil moisture content (%), soil temperature (℃), weed species and weed dry weight (g). Growth and yield parameters taken are: average plant height (cm), stem girth (cm), leaf area (m2), days to 50% flowering, root dry weight (g), shoot dry weight (g), weight of 1000 seeds and grain yield per land area. Weeds were identified and harvested, and their dry weights were taken and recorded. Data were also collected from ten randomly selected plants in each plot. The data were statistically analyzed using GENSTAT. The analysis of variance (ANOVA) was carried out to find out the significance of variation among the treatments while the significant differences between mean treatments were separated using Duncan’s Multiple Range Test (DMRT) at 5% level of probability. The results obtained from this study indicated that tillage methods and foliar fertilizer application significantly affected growth and yield parameters of sorghum, consequently the yield per unit area. The results also indicated that “Manually Tilled” seedbed (MT) improved soil physical properties better than either plots with PHR or No Till plots in the study area. Foliar fertilizer application at 2 l/ha performed best in terms of growth and yield. It is therefore recommended that manual tillage should be used as a method of seedbed preparation for sorghum production. However, better and stable grain yield of sorghum could be obtained with the practice of manual tillage (MT) in combination with foliar fertilization at rate of 2 litres/ha. It is recommended that different tillage methods should be combined with foliar fertilizer application for higher grain yield in the study area. 展开更多
关键词 Tillage method FOLIAR fertilIZER fertilIZER SORGHUM WEED Manual Yield
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Appropriate Location and Deployment Method for Successful Iron Fertilization
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作者 Tai-Jin Kim 《Open Journal of Marine Science》 2020年第3期149-172,共24页
“High nutrient, low chlorophyll (HNLC)” regions were created by locking iron into sedimentary iron sulfides with hydrogen sulfide available from volcanic eruptions in surrounding oceans. Appropriate locations and de... “High nutrient, low chlorophyll (HNLC)” regions were created by locking iron into sedimentary iron sulfides with hydrogen sulfide available from volcanic eruptions in surrounding oceans. Appropriate locations and deployment methods for the iron fertilization were far from volcanoes, earthquakes and boundaries of tectonic plates to reduce the chance of iron-locking by volcanic sulfur compounds. The appropriate locations for the large-scale iron fertilization are proposed as Shag Rocks in South Georgia and the Bransfield Strait in Drake Passage in the Southern Ocean due to their high momentum flux causing efficient iron deployment. The iron (Fe) replete compounds, consisting of natural clay, volcanic ash, agar, N<sub><span style="font-size:12px;font-family:Verdana;">2</sub><span style="font-size:12px;font-family:Verdana;">-fixing mucilaginous cyanobacteria, carbon black, biodegradable plastic foamed polylactic acid, fine wood chip, and iron-reducing marine bacterium, are deployed in the ocean to stay within a surface depth of 100<span style="font-family:""> <span style="font-size:12px;font-family:Verdana;"><span style="font-size:12px;font-family:Verdana;"><span style="font-family:Verdana;font-size:12px;">m for phytoplankton digestion. The deployment method of Fe-replete composite with a duration of at least several years for the successful iron fertilization, is configured to be on the streamline of the Antarctic Circumpolar Current (ACC). This will result in high momentum flux for its efficient dispersion on the ocean surface where diatom, copepods, krill and humpback whale stay together (~100<span style="font-family:""> <span style="font-family:""><span style="font-size:12px;font-family:Verdana;">m). Humpback whales are proposed as a biomarker for the successful iron fertilization in large-scale since humpback whales feed on krill, which in turn feed on cockpods and diatoms. The successful large-scale iron fertilization may be indicated by the return of the humpback whales if they could not be found for a long period before the iron fertilization. On-line monitoring for the successful iron fertilization focuses on the simultaneous changes of the following two groups;the increase concentration group (chlorophyll, O<sub><span style="font-size:12px;font-family:Verdana;">2</sub><span style="font-size:12px;font-family:Verdana;">, Dissolved Oxygen (DO), Di Methyl Sulfide (DMS)) and the decrease concentration group (nitrate, phosphate, silicate, CO<sub><span style="font-size:12px;font-family:Verdana;">2</sub><span style="font-size:12px;font-family:Verdana;">, Dissolved CO<sub><span style="font-size:12px;font-family:Verdana;">2</sub><span style="font-size:12px;font-family:Verdana;"> (DCO<sub><span style="font-size:12px;font-family:Verdana;">2</sub><span style="font-size:12px;font-family:Verdana;">)). The monitoring of chlorophyll-<span style="font-size:12px;font-family:Verdana;">a<span style="font-size:12px;font-family:Verdana;">, nitrate phosphate, and silicate concentrations after deploying the Fe-replete complex is carried out throughout the day and night for the accurate measurement of algal blooms. 展开更多
关键词 Appropriate Location Deployment method Iron fertilization Volcanic Sulfur Compounds Humpback Whale
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Effects of Sulfur Fertilizer Application Methods on Grain Protein Content During Filling Stage of Winter Wheat 被引量:6
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作者 谢迎新 郭天财 +2 位作者 朱云集 王晨阳 王永华 《Agricultural Science & Technology》 CAS 2009年第1期127-129,共3页
[ Objective] The experiment aimed to provide a theoretical base of optimal cultivation management for the high yield and good quality and high efficiency of winter wheat. [ Method] The effects of two sulfur fertilizer... [ Objective] The experiment aimed to provide a theoretical base of optimal cultivation management for the high yield and good quality and high efficiency of winter wheat. [ Method] The effects of two sulfur fertilizer application methods on dynamic changes of grain protein content and glutenin content of Yumai 49 and Yumai 66 during wheat grain filling stage were studied under the field conditions. [Result] Both the grain protein and glutenin content of two cultivars were increased by sulfur fertilizer, particularly, the effects on Yumai 49 were more significant.[ Conclusion] The grain content and glutenin content of different wheat cultivars could be increased by taking different sulfur fertilizer application methods. 展开更多
关键词 Winter wheat Sulfur fertilizer application method Grain protein content Glutenin content
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Leaching and Transformation of Nitrogen Fertilizers in Soil After Application of N with Irrigation: A Soil Column Method 被引量:60
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作者 ZHOU Jian-Bin XI Jin-Gen +1 位作者 CHEN Zhu-Jun LI Sheng-Xiu 《Pedosphere》 SCIE CAS CSCD 2006年第2期245-252,共8页
A soil column method was used to compare the effect of drip fertigation (the application of fertilizer through drip irrigation systems, DFI) on the leaching loss and transformation of urea-N in soil with that of surfa... A soil column method was used to compare the effect of drip fertigation (the application of fertilizer through drip irrigation systems, DFI) on the leaching loss and transformation of urea-N in soil with that of surface fertilization combined with flood irrigation (SFI), and to study the leaching loss and transformation of three kinds of nitrogen fertilizers (nitrate fertilizer, ammonium fertilizer, and urea fertilizer) in two contrasting soils after the fertigation. In comparison to SFI, DFI decreased leaching loss of urea-N from the soil and increased the mineral N (NH4+-N + NO3- -N) in the soil. The N leached from a clay loam soil ranged from 5.7% to 9.6% of the total N added as fertilizer, whereas for a sandy loam soil they ranged between 16.2% and 30.4%. Leaching losses of mineral N were higher when nitrate fertilizer was used compared to urea or ammonium fertilizer. Compared to the control (without urea addition), on the first day when soils were fertigated with urea, there were increases in NH4+-N in the soils. This confirmed the rapid hydrolysis of urea in soil during fertigation. NH4+-N in soils reached a peak about 5 days after fertigation, and due to nitrification it began to decrease at day 10. After applying NH4+-N fertilizer and urea and during the incubation period, the mineral nitrogen in the soil decreased. This may be related to the occurrence of NH4+-N fixation or volatilization in the soil during the fertigation process. 展开更多
关键词 FERTIGATION irrigation method N leaching N transformation nitrogen fertilizer
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Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin 被引量:11
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作者 DAI Jian-jun FAN Xiao-lin +2 位作者 YU Jian-gang LIU Fang ZHANG Qiao 《Agricultural Sciences in China》 CAS CSCD 2008年第9期1127-1132,共6页
The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dis... The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method. 展开更多
关键词 controlled release fertilizer (CRF) water soluble resin coating longevity of CRF rapid test method
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Response of Tomato Plants to a New Application Method of Polyolefin-Coated Fertilizer 被引量:3
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作者 TIAN Xiao-Hong M. SAIGUSA 《Pedosphere》 SCIE CAS CSCD 2005年第4期491-498,共8页
The response of tomato (Lycopersicon esculentum) plants basically fertilized with 0.3 g N per plant of compound fertilizer with a N:P2O5:K2O ratio of 20:10:20 to sticks of polyolefin-coated fertilizer (POCF) ... The response of tomato (Lycopersicon esculentum) plants basically fertilized with 0.3 g N per plant of compound fertilizer with a N:P2O5:K2O ratio of 20:10:20 to sticks of polyolefin-coated fertilizer (POCF) (LongT0 with a N:P2Os:K2O ratio of 14:12:14) applied 23 d after transplanting was investigated using rooting boxes in the greenhouse. The results at 26 and 40 d after stick fertilizer treatment showed that the use of the stick fertilizer greatly increased the production of many new fine roots from the tomato plants. Compared to the unfertilized control, root length and root length density in the stick fertilizer treatment increased by 3.6-6.7 fold. In the soil zones near the stick fertilizer, root weight and root mass density were also significantly higher for the stick fertilizer treatment. Additionally, the use of the stick fertilizer increased the N, P and K concentrations in the leaves and stems of the tomato plants. The new fine roots growing near the stick fertilizer not only absorbed more nutrients and translocated them to the shoots, but also contained more nutrients within themselves. The soil ammonium and nitrate N data showed that N released from the stick fertilizer played a major role in inducing the production of new fine roots. These results indicated that stick fertilizer could be used as an alternative to the co-situs application technique to change and control the root distribution of crops as well as to increase the potential capacity of roots for water and nutrient absorption. 展开更多
关键词 application method controlled release fertilizer tomato (Lycopersicon esculentum)
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Effects of Different Soil Preparation and Fertilizer Application Methods on the Growth and Yield of the Rice-Crayfish Rotation Direct Seeding Rice Nongxiang 32 被引量:1
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作者 DAI Li TAO Shu-hua +4 位作者 HU Wen-bin LIU Ye LI Wen-zhong FANG Bao-hua ZHAO Zheng-hong 《Agricultural Science & Technology》 CAS 2021年第2期6-12,共7页
In order to improve the yield and fertilizer utilization of the ricecrayfish rotation and direct seeding rice Nongxiang 32,the effects of different soil preparation and fertilizer application methods on the growth,yie... In order to improve the yield and fertilizer utilization of the ricecrayfish rotation and direct seeding rice Nongxiang 32,the effects of different soil preparation and fertilizer application methods on the growth,yield and fertilizer utilization of the variety were studied.The results showed that,under the rice-crayfish rotation and direct seeding farming mode,the contributions of seed setting rate,1000-grain weight,yield,and fertilizer contribution rate to yield of Nongxiang 32 in the treatments with rotary tillage with base fertilizer,rotary tillage without base fertilizer and no-tillage with base fertilizer were relatively higher than those in the treatments with rotary tillage without fertilizer,no-tillage without fertilizer and no-tillage without base fertilizer,and there were no significant differences between the three treatments.Rotary tillage with base fertilizer and rotary tillage without base fertilizer significantly increased the total number of stems and tillers,total number of ears,and number of effective ears.Rotary tillage and application of base fertilizer also significantly increased the number of tillers,plant weight and weed suppression ability in the early stage of rice growth.Therefore,in the different soil preparation and fertilizer application methods,the application of base fertilizer with rotary tillage was the best,followed by rotary tillage without base fertilizer and no-tillage with base fertilizer. 展开更多
关键词 Rice-crayfish rotation Direct seeding Rotary tillage NO-TILLAGE fertilization method
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Terminal fertility control: Clients’ own reason for the choice of the contraceptive method
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作者 Daniel Adebode Adekanle Adeola Folashade Afolabi Adewale Samson Adeyemi 《Open Journal of Obstetrics and Gynecology》 2013年第9期706-709,共4页
Background: The prevalence of contraceptive use has increased worldwide due to the development and introduction of modern contraceptives and the establishment of organized family planning programs. In Nigeria, there i... Background: The prevalence of contraceptive use has increased worldwide due to the development and introduction of modern contraceptives and the establishment of organized family planning programs. In Nigeria, there is a very slow rise in contraceptive use prevalence, resulting in high fertility rate. Generally contraceptive is either used for birth spacing, or for the purpose of terminal fertility control to limit the number of children, and the choice of method for this purpose varies. Aims and Objectives: To determine the contraceptive methods of choice among clients seeking terminal fertility control, and their reasons for the choice of such methods. Materials and Methods: A cross-sectional study of clients attending the family planning clinic of Ladoke Akintola University of Technology Teaching hospital over a period of twenty-four months, between July, 2009 and June, 2011. All clients who had completed their family, and wanted a contraceptive method to limit their family size filled the semi-structured questionnaire after giving their informed consent. Clients’ own reasons for the choice of the particular contraceptive method were grouped, entered into SPSS work sheet, and analyzed using SPSS version 17. Result: There were five hundred and ninety-two new contraceptive method acceptors during the study period, of which 264 (44.6%) were for terminal fertility control. Progestogen-only injectable contraceptive was the method of choice for terminal fertility control by 145 (54.9%) of the clients, while 85 (32.2%) made intrauterine contraceptive device (copper-T) their method of choice, and the least chosen method was female surgical sterilization (2, 0.8%). Ease of administration, satisfaction with previous use, long duration of action, and husband’s preference were the reasons for the choice of the methods. Conclusion: There is awareness of terminal fertility control in Nigeria, especially in the southwestern region of the country, and this may be responsible for the decreasing prevalence of grandmultiparity in the region. However, reversible contraceptive method is the preferred option for this purpose. 展开更多
关键词 TERMINAL fertility Control method CHOICE REASONS
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Preparation of Silicon Fertilizer Using Lithium Pyroxene Acid-leaching Residues as Starting Materials
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作者 CHEN Jianghua LUO Dawei +2 位作者 GAO Zijie RONG Ke DENG Jiabao 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期389-399,共11页
We focus on a novel and economical route for the synthesis of Si fertilizer via the calcination method using lithium pyroxene acid-leaching residues as the starting materials.The molar ratio of Si/K/Ca of 1:1.4:0.8,ca... We focus on a novel and economical route for the synthesis of Si fertilizer via the calcination method using lithium pyroxene acid-leaching residues as the starting materials.The molar ratio of Si/K/Ca of 1:1.4:0.8,calcination temperature of 900℃and calcination time of 120 min were identified as the optimal conditions to maximize the available Si content of the prepared Si fertilizer.The performance of the resulting product satisfies the Chinese agricultural standard for silica fertilizers,providing a new solution for the large-scale harmless and sustainable reuse of lithium pyroxene tailings.The X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR)characterization elucidated the formation mechanism of silica fertilizers,and identified KAlSiO_(4)and K_(4)CaSi_(3)O_(9)as the primary silicates products.Observation of the surface morphology of the samples was conducted by scanning electron microscopy(SEM)and X-ray energy dispersive spectrometry(EDS),and compositional analysis of the micro-regions.The acceleration action of CaCO_(3)in the decomposition process of lithium pyroxene acid-leaching residues was demonstrated by the thermogravimetry-differential scanning calorimetry(TG-DSC)test.Determination of heavy metal elements in Si fertilizer was performed by ICP-OES.Potting experiments confirmed that the best growth of pakchoi was achieved when 5 g·kg^(-1)of Si fertilizer was applied.These evidence suggests that the Si fertilizer prepared in this study is a promising candidate for a silica-supplemented soil. 展开更多
关键词 lithium pyroxene acid-leaching residues available silicon calcination method Si fertilizer
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耕作方式、有机肥、秸秆还田对小麦赤霉病和茎基腐病的影响
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作者 李保军 温国昌 +5 位作者 陈洁 崔晓敬 贾良良 杨云马 杨璞 李红铁 《中国农学通报》 2026年第2期184-190,共7页
为探明耕作方式、有机肥替代部分化肥及秸秆还田对小麦赤霉病和茎基腐病的影响,于2022—2024年进行田间试验。试验采用裂区与大区对比设计:裂区设计中,主区设DT(隔年翻耕,耕深25 cm)、RT(连年旋耕,耕深15 cm)2个处理;副区设OMC(发酵牛... 为探明耕作方式、有机肥替代部分化肥及秸秆还田对小麦赤霉病和茎基腐病的影响,于2022—2024年进行田间试验。试验采用裂区与大区对比设计:裂区设计中,主区设DT(隔年翻耕,耕深25 cm)、RT(连年旋耕,耕深15 cm)2个处理;副区设OMC(发酵牛粪有机肥替代25%基施化肥)、OMP(发酵猪粪有机肥替代25%基施化肥)、CK(常规施肥)3个处理。秸秆还田因素采用大区对比设计。结果表明,在多年单作棉花后的一个玉米-小麦轮作周期内,DT与RT处理间赤霉病病穗率差异不显著。在DT条件下,OMC处理较CK可显著降低小麦赤霉病的病穗率6.4个百分点(P<0.05),OMP处理降低不显著;在RT条件下,OMC和OMP处理对降低小麦赤霉病的病穗率均不显著;秸秆不还田下,OMC和OMP处理病穗率较CK分别升高1.2和1.8个百分点(P>0.05);玉米秸秆还田处理较不还田处理显著降低小麦赤霉病病穗率34.2%(P<0.05);相同遗传背景下,环境因子对产量的提升和赤霉病病穗率的降低存在矛盾。在多年单作棉花后的两个玉米-小麦轮作周期内,在CK条件下,DT翌年RT处理较连年RT处理显著降低茎基腐病病指9.0%(P<0.05);在DT条件下,OMC处理较CK显著降低茎基腐病病指34.2%(P<0.05),OMP处理降低不显著;在RT条件下,OMC处理较CK显著降低茎基腐病病指23.4%(P<0.05),而OMP处理显著增加茎基腐病病指;玉米秸秆还田处理较不还田处理显著降低小麦茎基腐的发病率和发病指数,其中病指防效为11.0%(P<0.05)。 展开更多
关键词 小麦 耕作方式 有机肥 秸秆还田 赤霉病 茎基腐病
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黑土地平衡施肥数量及其种类配比研究
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作者 周道玮 李强 +2 位作者 胡娟 于达夫 石记博 《中国农学通报》 2026年第2期103-112,共10页
为简化施肥量确定方法并优化肥料养分配比,本研究基于修正的施肥量计算公式,建立了施肥量权衡选择法及养分相对丰度法。利用权衡选择法,计算得出东北黑土区主要土壤类型(风沙土、壤性黑钙土、典型黑土)种植玉米、小麦和花生所需要的施... 为简化施肥量确定方法并优化肥料养分配比,本研究基于修正的施肥量计算公式,建立了施肥量权衡选择法及养分相对丰度法。利用权衡选择法,计算得出东北黑土区主要土壤类型(风沙土、壤性黑钙土、典型黑土)种植玉米、小麦和花生所需要的施肥量。计算结果与当地的实际施肥量吻合,表明现行施肥量处于适宜水平;利用养分相对丰度法,计算了不同土壤-作物组合下掺混肥或复合肥的优化配比方案,推荐东北黑土区相应土壤类型配制掺混肥或复合肥采用N:P_(2)O_(5):K_(2)O=25:10:15的配比方案,以实现施肥量与作物养分需求的匹配。在土壤有效养分供给量与肥料损失量平衡的条件下,施肥量应遵循“按需供给”原则,并精准匹配作物养分需求阈值。 展开更多
关键词 施肥量 种类配比 权衡选择法 相对丰度法 黑土
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合肥市辣椒种植基地不同土层深度肥力特征研究
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作者 李文昭 何行 +2 位作者 隋常玲 杨胜香 颜雄 《合肥师范学院学报》 2026年第1期96-100,共5页
为研究合肥市虾子镇辣椒种植基地不同土层深度肥力特征,对各土层土壤有机质、全氮、全磷、全钾等肥力指标的含量进行测定分析,并利用内梅罗指数法评估土壤肥力等级。结果表明:(1)土壤有机质和全钾含量处于中等水平,全氮含量极为匮乏,而... 为研究合肥市虾子镇辣椒种植基地不同土层深度肥力特征,对各土层土壤有机质、全氮、全磷、全钾等肥力指标的含量进行测定分析,并利用内梅罗指数法评估土壤肥力等级。结果表明:(1)土壤有机质和全钾含量处于中等水平,全氮含量极为匮乏,而全磷含量却相对丰富。随着土层深度的递增,有机质和全氮的含量呈现递减趋势;相反,全磷和全钾的含量则随着土层深度的增加而上升。(2)不同土层的综合肥力系数值波动在0.905至1.008之间,0~10 cm、10~20 cm和20~30 cm土层的土壤肥力系数均处于Ⅲ级水平,该辣椒种植基地的土壤整体肥力一般。 展开更多
关键词 辣椒种植基地 不同土层 肥力特征 内梅罗指数法
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肥料级磷酸一铵制备电池级磷酸铁的工艺研究
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作者 李佩雯 邱佳璐 +4 位作者 龙秉文 张逸 邓伏礼 刘生鹏 丁一刚 《化学与生物工程》 北大核心 2026年第2期15-20,26,共7页
以肥料级磷酸一铵(MAP)为磷源、硫酸亚铁为铁源,采用均相沉淀法制备电池级磷酸铁,并对制备工艺进行了研究。结果表明:当肥料级MAP与纯水质量比为2∶10、溶解温度为75℃、溶解时间为1.0 h时,肥料级MAP的溶解率为74.52%;溶解液在氨化pH值... 以肥料级磷酸一铵(MAP)为磷源、硫酸亚铁为铁源,采用均相沉淀法制备电池级磷酸铁,并对制备工艺进行了研究。结果表明:当肥料级MAP与纯水质量比为2∶10、溶解温度为75℃、溶解时间为1.0 h时,肥料级MAP的溶解率为74.52%;溶解液在氨化pH值为7.0、氨化温度为20℃、氨化时间为1 h的条件下除杂,磷损失率为1.9%;当硫酸亚铁溶液与磷铵净化液物质的量比为1.0∶1、pH值为2.0、陈化温度为85~90℃、陈化时间为120 min时,可获得晶型结构完整、铁含量为36.20%、磷含量为20.98%、铁磷比为0.96、平均粒径为235.1 nm的电池级磷酸铁。肥料级MAP制备电池级磷酸铁不仅可以降低磷源成本,而且可为肥料级MAP的高值化利用提供一条可行的途径,具有较好的应用前景。 展开更多
关键词 肥料级磷酸一铵 净化 均相沉淀法 电池级磷酸铁
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儿童托幼费用对女性生育意愿的影响研究
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作者 郭建君 黄乾 董长瑞 《中央财经大学学报》 北大核心 2026年第2期133-143,共11页
近年来,我国居民的总和生育率呈现不断下降的趋势,这与女性低迷的生育意愿有着紧密联系。女性在家庭中往往承担着养育子女的主要责任,与托幼服务相关的成本负担可能会对女性生育意愿产生一定的负面影响。文章基于2017年全国生育状况抽... 近年来,我国居民的总和生育率呈现不断下降的趋势,这与女性低迷的生育意愿有着紧密联系。女性在家庭中往往承担着养育子女的主要责任,与托幼服务相关的成本负担可能会对女性生育意愿产生一定的负面影响。文章基于2017年全国生育状况抽样调查数据,创新使用Heckman两阶段方法处理了样本选择偏差,并实证分析了儿童托幼费用对女性生育意愿的影响。研究结果发现:在纠正样本选择偏误后,儿童托幼费用的增加显著降低了女性的生育意愿。异质性分析表明,农村、受教育水平较高、35岁以下和中低收入家庭女性的生育意愿受儿童托幼费用增加的负向影响更显著。在生育意愿日趋低迷的背景下,构建普惠托幼服务体系、创造生育友好型社会和倡导夫妻共同承担育儿责任是提高我国女性生育意愿的重要措施。 展开更多
关键词 低生育率 托幼费用 生育意愿 Heckman两阶段方法
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不同培肥措施对褐土土壤微生物群落和酶活性的影响
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作者 殷浩凯 李倩 +5 位作者 赵宇航 解文艳 周怀平 杨振兴 刘志平 贺丽燕 《环境科学》 北大核心 2026年第2期1366-1378,共13页
探讨不同培肥措施对褐土农田养分和冬小麦产量的影响,解析土壤胞外酶和微生物群落的变化特征,为高效提升褐土农田土壤肥力和冬小麦产量提供理论依据.基于2017~2024年连续7a的定位试验,包括5种不同培肥措施:不施肥处理(CK)、常规施肥处理... 探讨不同培肥措施对褐土农田养分和冬小麦产量的影响,解析土壤胞外酶和微生物群落的变化特征,为高效提升褐土农田土壤肥力和冬小麦产量提供理论依据.基于2017~2024年连续7a的定位试验,包括5种不同培肥措施:不施肥处理(CK)、常规施肥处理(NPK)、优化施肥处理(NPKM)、单施有机肥处理(OM)和常规施肥+秸秆直接还田处理(NPKS),利用高通量测序技术和生态网络方法,综合分析了土壤养分含量、胞外酶活性、细菌和真菌群落结构和功能.结果表明:①不同培肥措施(NPK、NPKM、NPKS和OM)均可以提高土壤肥力、小麦产量和胞外酶活性,其中NPKS处理提升效果最为显著.②不同培肥措施改变了土壤细菌群落结构组成,不同培肥措施均提高了变形菌门和拟杆菌门的相对丰度,降低了酸杆菌门的相对丰度;SOC、UE和TP是影响细菌群落组成的重要影响因素.③土壤真菌优势门为子囊菌门、担子菌门和被孢霉门;均提高了子囊菌门和被孢霉门相对丰度;DHA、AP和UE是影响真菌群落组成的重要影响因素.④不同培肥措施增加了土壤细菌群落网络的复杂性,降低了土壤真菌群落网络的复杂性.⑤FAPROTAX细菌功能预测结果表明,不同培肥措施提高了土壤碳氮循环相关功能;FUNGuild真菌功能预测表明,秸秆还田可以抑制土壤病原菌的生长,而施加有机肥则会促进腐生真菌生长.不同培肥措施均可提高土壤肥力和胞外酶活性,增加有益菌群丰度,显著改变土壤微生物群落结构和组成,促进土壤碳氮循环,秸秆还田可以抑制土壤病原菌的生长.有机无机配施(NPKS和NPKM)提升效果优于单施化肥(NPK)和单施有机肥(OM),有机无机配施有利于改善土壤质量,促进碳和氮循环,提高作物产量,从而实现旱作农业的可持续发展. 展开更多
关键词 施肥方式 微生物群落 酶活性 土壤养分 高通量测序 共现网络
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不同灌溉方式和施肥水平对土壤养分和三七生理生长的影响
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作者 梁嘉平 汪国升 +3 位作者 何彦名 梁永鸿 杨启良 王海东 《干旱地区农业研究》 北大核心 2026年第1期126-135,277,共11页
为揭示不同灌溉方式和施肥量对土壤养分和三七生理生长的影响机制,提出适宜于三七水肥需求的灌溉施肥策略,以5年生三七为研究对象,设置3种灌溉方式(增氧地下滴灌(OI)、微喷灌(SI)和地表滴灌(DI))和4个有机肥施肥水平(F_(1):75 kg·h... 为揭示不同灌溉方式和施肥量对土壤养分和三七生理生长的影响机制,提出适宜于三七水肥需求的灌溉施肥策略,以5年生三七为研究对象,设置3种灌溉方式(增氧地下滴灌(OI)、微喷灌(SI)和地表滴灌(DI))和4个有机肥施肥水平(F_(1):75 kg·hm^(-2)、F_(2):100 kg·hm^(-2)、F_(3):125 kg·hm^(-2)和F_(4):150 kg·hm^(-2)),研究不同灌溉方式和施肥量对土壤养分含量、三七生长指标、叶片光合特性和根腐病发病率的影响。结果表明,OIF_(4)处理有利于根区土壤养分的提升,0~30 cm土层生育期土壤硝态氮、速效磷、速效钾、有机质含量分别较其余处理提高8.7%~55.9%、14.5%~51.9%、1.2%~34.6%、2.2%~29.4%;SIF_(3)处理有利于三七生长和光合特性提升,株高、茎粗、叶长、叶宽、净光合速率(P_(n))、叶片气孔导度(G_(s))、叶片蒸腾速率(T_(r))分别较其他处理增加30.04%~47.21%、39.06%~60.77%、9.19%~22.29%、15.51%~26.29%、35.59%~52.99%、131.54%~190.16%、17.06%~21.71%。OIF_(3)处理下三七苗期、花期和果期的根腐病发病率最低,分别为5.72%、7.98%和9.07%;且其苗期、花期和果期的单株根鲜质量和干质量最大,分别较其余处理提高10.2%~50.3%和21.8%~63.2%。综上可知,增氧地下滴灌+有机肥施用量125 kg·hm^(-2)为降低三七根腐病发病率,同时促进三七根系生长的最佳灌溉方式和有机肥施用量组合。 展开更多
关键词 三七 灌溉方式 有机肥施用量 土壤养分 根腐病 根系生物量
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基于离散元法的横向交错式外槽轮排肥器参数优化与试验
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作者 王守江 罗长海 +2 位作者 董建军 崔林 武广伟 《农机化研究》 北大核心 2026年第1期127-135,共9页
针对外槽轮排肥器排肥脉动现象造成排肥均匀性较低的问题,设计了一种横向交错式外槽轮排肥器。结合理论分析对其关键部件进行结构设计,并基于离散元法开展参数优化,通过台架试验验证横向交错式外槽轮排肥器的作业性能。以不同结构的横... 针对外槽轮排肥器排肥脉动现象造成排肥均匀性较低的问题,设计了一种横向交错式外槽轮排肥器。结合理论分析对其关键部件进行结构设计,并基于离散元法开展参数优化,通过台架试验验证横向交错式外槽轮排肥器的作业性能。以不同结构的横向交错式外槽轮进行仿真试验,结果表明槽齿数为8个、横向分段数为2格的排肥器具有较优的排肥性能,优化后的排肥均匀变异系数最小值为4.75%,小于原外槽轮排肥器。以不同转速(30~90 r/min)和不同类型肥料(复合肥料、尿素、稳定性复合肥料)为试验因素进行台架试验,结果表明:在不同试验条件下,槽齿数为8个、横向分段数为2格的横向交错式外槽轮排肥器的排肥均匀变异系数最小值为5.40%,小于原外槽轮排肥器,证实了横向交错式外槽轮排肥器排肥均匀性能较优,可为外槽轮排肥装置的设计与研究提供参考和理论依据。 展开更多
关键词 排肥器 横向交错式外槽轮 排肥均匀性 离散元 参数优化 台架试验
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高效包封黄腐酸微胶囊的制备及其缓释肥效研究
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作者 杨丽 强涛涛 +3 位作者 魏熠曦 任龙芳 孙新 张显成 《皮革科学与工程》 北大核心 2026年第2期9-17,25,共10页
【目的】为了解决黄腐酸(BFA)在应用中易降解、稳定性不足的问题,【方法】采用复凝聚法,以明胶(GEL)和黄原胶(XG)作为壁材,BFA为芯材,戊二醛为交联剂,制备了黄腐酸微胶囊(BFAM)。【结果】单因素实验与正交试验优化出BFAM的最佳制备条件... 【目的】为了解决黄腐酸(BFA)在应用中易降解、稳定性不足的问题,【方法】采用复凝聚法,以明胶(GEL)和黄原胶(XG)作为壁材,BFA为芯材,戊二醛为交联剂,制备了黄腐酸微胶囊(BFAM)。【结果】单因素实验与正交试验优化出BFAM的最佳制备条件为:m(GEL)∶m(XG)为10∶1,反应温度60℃、pH 3.5,BFA用量200 mg,戊二醛用量1.5%;在此条件下,BFAM的包封率达到94.7%。傅里叶变换红外光谱、热重分析、X射线衍射及扫描电子显微镜表征结果证实BFA被成功包裹于壁材中,且BFAM的稳定性显著优于BFA。同时,BFAM组优于清水种植组和BFA种植组,奶油小白菜的株高与总叶绿素含量得到了明显提升。【结论】BFAM可通过缓释作用高效发挥肥效,显著提升BFA的稳定性,研究为BFA的高效应用提供了新思路。 展开更多
关键词 黄腐酸 微胶囊 复凝聚法 明胶 黄原胶 缓释肥
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氮肥用量和栽插方式对双季稻产量和氮素吸收利用的影响
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作者 李大明 胡丹丹 +8 位作者 成艳红 徐小林 程坤 宋惠洁 吴艳 吴成彧 柳开楼 胡志华 余喜初 《中国土壤与肥料》 北大核心 2026年第1期131-139,共9页
双季稻是我国南方最重要的粮食种植模式,明确双季稻不同栽插方式下氮肥用量对水稻产量和氮素吸收利用特征可为构建双季稻科学高效的氮素管理方案提供数据支撑。以养分专家系统(NE)推荐的施氮量为基础,设置氮肥施用量梯度(NE、NE-25%N、N... 双季稻是我国南方最重要的粮食种植模式,明确双季稻不同栽插方式下氮肥用量对水稻产量和氮素吸收利用特征可为构建双季稻科学高效的氮素管理方案提供数据支撑。以养分专家系统(NE)推荐的施氮量为基础,设置氮肥施用量梯度(NE、NE-25%N、NE+25%N、NE-50%N、NE+50N%和NE-100%N),于2021—2022年开展2年4季田间试验,比较不同栽插方式(人工移栽、机插、抛秧、直播)下氮肥用量对水稻产量、氮素吸收利用、氮肥利用效率等的影响,并分析水稻产量与氮肥用量的关系。结果发现,栽插方式和施氮量显著影响双季稻产量。相同施氮量下,人工移栽早稻产量最高,直播方式早、晚稻产量均最低。与NE推荐施肥量相比,在NE基础上氮肥用量增加50%以及减少25%和50%在不同栽插方式下早、晚稻产量均降低。栽插方式和施氮量显著影响水稻氮素累积量。早稻季,与NE处理相比,NE-25%N处理在人工移栽和直播方式下氮肥利用率分别降低21.89和11.16个百分点,在抛秧和机插方式下分别提高3.37和2.56个百分点。晚稻季,抛秧和直播方式下NE-25%N处理较NE处理氮肥利用率分别显著增加14.75和11.12个百分点。在NE基础上减少氮肥用量25%对早、晚稻氮肥农学效率影响不显著,增加氮肥用量降低了水稻氮肥农学效率。不同栽插方式下,早、晚稻的产量潜力对应的氮肥合理用量需求不同,早稻人工移栽方式下氮肥需求量最高,为164.72 kg/hm^(2),与机插、抛秧和直播方式相比氮肥需求量分别增加4.4%、3.1%和2.5%;而晚稻机插方式氮肥需求量最高,为163.84 kg/hm^(2),与人工移栽、抛秧和直播方式相比氮肥需求量分别提高9.7%、2.5%和2.4%。栽插方式和施氮量显著影响双季稻的产量、氮素吸收利用、氮肥利用效率,NE推荐施氮量和人工移栽方式产量最高。NE推荐的施氮量可以满足水稻的生长,并提高氮素吸收利用和氮肥利用效率;不同栽插方式和种植季的产量潜力与氮肥需求量存在差异,生产上可依据栽插方式和种植季节优化氮肥的投入。 展开更多
关键词 养分专家系统 氮肥用量 栽插方式 氮素吸收利用 双季稻
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复合肥料中总氮含量的测定方法探究
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作者 许焱炜 陆银萍 《化工设计通讯》 2026年第1期8-10,共3页
氮素是农作物生长发育的关键元素,其含量和吸收率直接影响复合肥料的施用效果。文章主要以如何实现复合肥料中总氮含量的测定为重点进行阐述,首先介绍复合肥料中总氮含量的测定过程,其次阐述总氮含量的测定结果验证,最后深入说明凯氏定... 氮素是农作物生长发育的关键元素,其含量和吸收率直接影响复合肥料的施用效果。文章主要以如何实现复合肥料中总氮含量的测定为重点进行阐述,首先介绍复合肥料中总氮含量的测定过程,其次阐述总氮含量的测定结果验证,最后深入说明凯氏定氮法测定复合肥料中总氮含量的思考,旨在推动肥料质量监管工作的发展。 展开更多
关键词 复合肥料 总氮含量 测定方法 精准化
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