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81.
82.
North Carolina rock phosphate (NCRP) (highly carbonate—substituted apatite) was ground to produce three samples with different particle size distributions. The effectiveness of these fertilizers was compared with the effectiveness of superphosphate in a field experiment and three glasshouse experiments using lateritic soils from south-western Australia. Non-reactive Queensland rock phosphate (low carbonate-substituted apatite from the Duchess deposit) was also used in the pot experiments. Bicarbonate-soluble phosphorus extracted from the soil is widely used in Western Australia to predict plant yields from previously-applied fertilizer dressings. For both field and pot experiments bicarbonate-extractable phosphorus (soil test value) was measured and related to subsequent plant yields.As calculated from the initial slope of the relationship between yield and the level of P applied, finely powdered NCRP was about 5–32% as effective as freshly-applied superphosphate in the year of application and also for two years after application in the field experiment, and for two successive crops in the three pot experiments. For both field and pot experiments, finely powdered NCRP, was at best, 1.5–2.0 times as effective as granular NCRP. Relative to freshly-applied superphosphate, the effectiveness of rock phosphates usually decreased with increasing level of application.For each of the crops in the field experiment, the relationships between yield and phosphorus content of plants (i.e. internal efficiency curves) were similar for all fertilizers. Thus the low effectiveness of the rock phosphates relative to superphosphate was solely due to much less phosphorus being taken up by plants. By contrast, in the pot experiments internal efficiency curves differed for different fertilizers. This is attributed to differences in the rate of phosphorus uptake by plant roots during the early stages of plant growth.For both field and pot experiments, soil test calibrations (the relationship between yield and soil test value) differed for rock phosphates and superphosphate. For superphosphate, soil test calibrations also differed for the three different years after the initial application of this fertilizer in the field experiment. For the second crop in the pot experiment, soil test calibrations differed for superphosphate applied at different times (before the first and the second crop). These results point out the difficulty of applying soil testing procedures to soils that have experienced different histories of fertilizer application. 相似文献
83.
Mussoorrie rock phosphate (MRP), MRP + pyrite (25% by weight), diammonium phosphate (DAP), ammonium polyphosphate (APP) and nitrophosphate (NP) were compared in a field experiment as fertilizers for wheat. At 20 kg P ha–1, MRP was only 6 per cent as effective as DAP. However, when it was mixed with pyrite, the efficiency of MRP increased to 64 per cent at 20 kg P ha–1 compared with 97 per cent at 40 kg P ha–1. The P requirement for a targeted yield for 4.5 t ha–1 decreased from 39.4 kg P ha–1 as MRP to 23.7 kg P ha–1 as MRP + pyrite. Of the other P fertilizers studied, NP was as effective as DAP, whereas APP was 9 to 37 per cent more effective than DAP. However, the P requirement as DAP, NP and APP for a targeted yield of 4.5 t ha–1 was similar (11 ± 0.5 kg P ha–1). 相似文献
84.
介绍安徽六国化工股份有限公司24万t/a DAP的工艺概况及试车、运行、技改情况.针对2001年7月试车初期出现的问题,例如中和槽到氨化粒化器料浆泵送管线及泵易堵,造粒机管梁定位设计缺陷、氨分布器角度设置不合理等进行了整改.并对中和造粒尾气洗涤系统和磷铵产品外观质量提出了改进意见. 相似文献
85.
采用高温熔融法,在磷酸盐玻璃的配合料中引入抗菌剂硝酸银,一次熔化制得抗菌玻璃材料。通过对磷酸盐玻璃的抗菌性能和缓释性能分析,结果表明:制备抗菌磷酸盐玻璃,合适的银含量为1.5%~2.0%(质量),处理温度在1200~1350℃,即可获得良好的抗菌效果和缓释性。 相似文献
86.
用305酯(双季戊四醇酯)增塑剂与其他添加剂配合使用,部分取代TOTM(偏苯三酸三辛酯)生产船用105℃PVC(聚氯乙烯)电线电缆料,并对其电性能,浸水后电性能等进行测试分析。结果表明,305酯为主增塑剂剂时,与4~5份的TCP(磷酸三甲酚酯)并用可以显著改善电缆料浸水电性能。在配方中应用二盐基性苯二甲酸铅和二盐基硬脂酸铅作稳定系统,更能保证电线电缆料浸水电性能的稳定。 相似文献
87.
研究了四丁基氢氧化胺模板磷酸铝对水中重金属离子铬(Ⅵ)的吸附特性。结果表明:四丁基氢氧化胺模板磷酸铝对铬(Ⅵ)吸附的最佳pH值和铬(Ⅵ)的初始质量浓度分别为2.0和40mg/L,且其吸附等温线符合Freundlich模型。 相似文献
88.
一种具有发展前景的饲料磷酸盐——脱氟磷酸三钙 总被引:3,自引:0,他引:3
脱氟磷酸三钙由于含钙量高、钙磷比适合于喂养家禽,是良好的饲料磷酸盐。它是由磷矿和其它添加物团粒,经高温焙烧后制成。具有工艺流程简单、生产成本低等优点。可结合本地情况,发展生产。 相似文献
89.
The effectiveness of large single applications of North Carolina reactive rock phosphate, Queensland non-reactive rock phosphate, and Calciphos, were compared to the effectiveness of superphosphate in field experiments in south-western Australia for up to 11 years after application. As measured using plant yield, superphosphate was the most effective fertilizer in the year of application, and relative to freshly-applied superphosphate, the effectiveness of the superphosphate residues declined to be about 15 to 65% as effective in the year after application, and 5 to 20% as effective 9 to 10 years after application. Relative to freshly-applied superphosphate, all the rock phosphates were 10 to 30% as effective in the year of application, and the residues remained 2 to 20% as effective in the 10 years after application. The bicarbonate soil test reagent predicted a more gradual decrease in effectiveness of superphosphate of up to 70% 10 years after application. For rock phosphate, the reagent predicted effectiveness to be always lower than for superphosphate, being initially 2 to 11% as effective in the year after application, and from 10% to equally as effective 10 years later. Therefore rock phosphates are unlikely to be economic alternatives to superphosphate in the short or long term on most lateritic soils in south-western Australia. 相似文献
90.
重钙装置改产磷铵后,造粒机内的物料行为发生了变化,即“料浆涂布-水分蒸发-氨化反应”这一物理化学过程。喷氨孔与水平线的夹角是影响这一过程的重要因素,本文对夹角的确定进行了理论分析。在实验基础上,对造粒机预中和料浆喷头位置、氨分布管的长度和角度进行了重新配置。生产表明,重新配置的造粒机内部构件具有很好的造粒效果。 相似文献