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包膜型缓控释肥料的研究综述 总被引:1,自引:0,他引:1
缓控释肥料作为一种新型肥料以其明显提高肥料利用率,降低养分流失量业已成为国内外研究的热点之一。本文系统论述了缓控释肥料的概念、分类、评价方法、包膜工艺及作用机理。讨论了国内包膜型缓控释肥料发展和研究现状;综合分析了我国包膜型缓控释肥料在生产和应用方面存在的问题及其发展方向。 相似文献
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缓/控释肥料(Slavand Controlled Release Fertilizer,SCRF)的生产和使用技术已有30多年历史,其作用是使肥料施入土壤后的释放行为与作物整个生长期的需肥规律一致,在作物生长初期供肥不过剩,在作物生长中、后期供肥不短缺,且不需进行追肥。缓/控释肥料的工艺多种多样,如利用天然存在的有机物、微溶合成化合物以及物理包膜等。物理包膜技术发展较快,包膜物料也呈多样化,如石腊、合成聚合物等,其中以肥包膜广为业界关注,如以钙镁磷肥包膜、硫磺包膜等。 相似文献
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缓/控释肥料的研究现状及进展 总被引:2,自引:0,他引:2
在查阅大量有关缓/控释化肥资料的基础上,简要介绍了缓/控释肥料的发展历程,概述了缓/控释肥料的发展状况,对缓/控释肥料的发展前景进行了展望。 相似文献
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缓/控释肥料及其在水稻上的应用 总被引:4,自引:0,他引:4
近20多年来,我国化肥用量持续高速增长,粮食产量却始终增加缓慢.而且,农田盲目施肥造成的资源浪费和水质、空气、土壤的污染问题已引起社会的普遍关注.缓/控释肥是一种根据作物的需要缓慢释放养分的新型肥料,它为解决传统化肥带来的一系列问题提出了新的思路和途径.我国缓/控释的研究还处初级发展阶段,基础研究滞后,目前还没有真正的控释肥料推广应用于水稻等大田作物上.本文介绍了缓/控释肥的定义,阐述了我国缓/控释肥的研究与应用现状;综述了水稻专用缓/控释肥的作用机制及其对水稻生长及产量的影响;简要介绍了新型缓/控释肥-种子包衣肥;指出了缓/控释肥的发展趋势. 相似文献
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包膜缓控释肥料用包膜材料的探讨 总被引:2,自引:0,他引:2
简要介绍关于目前国内外缓控释肥料的生产及包膜缓控释肥料生产用包膜材料的种类和特点;阐述开发利用缓效、长效肥料,特别是水溶性低的肥料为速溶、速效性肥料的缓控释包膜材料,采用“以肥包肥”缓控释技术的必要性及取得的成果. 相似文献
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利用复混肥装置改产新型(胶结包膜型)缓/控释肥料是化学肥料产品结构调整的方向之一,着重介绍了改造背景、工艺技术路线说明、胶结包膜型缓/控释尿素的作用机理、技术创新点、产品质量标准、主要设备选型、投资效益分析、技术经济性能等. 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献