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阐述腐植酸磷肥的成肥机制,腐植酸磷肥的分类、功效、应用及发展前景。腐植酸具有特殊功能,发展腐植酸磷肥为解决磷肥利用率低、污染环境等问题提供了一条新途径。 相似文献
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磷矿石是制造磷肥等磷化工的主要原料,是不可再生资源。我国在磷矿石开采和利用方面,用富弃贫,磷矿石利用率低、低品位磷矿石堆积,既占用土地又污染环境。 相似文献
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我国作物生产从20世纪70年代后期开始大规模使用磷肥,过量施用现象普遍.目前磷肥当季利用率低,粮食作物约20%,蔬菜果树不足10%;残留在土壤中的磷还存在污染水体的风险.如何提高磷肥利用效率是关乎作物生产绿色提质增效的重大问题.
磷肥-土壤-作物体系不匹配、过度依赖高浓度水溶性磷肥、忽视作物高效吸收利用磷的生物学潜力在... 相似文献
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我国加入世界贸易组织在即。而我国磷肥工业如何在市场竞争中立于不败之地 ?已成为必须抓紧研究和回答的一项重大课题。目前我国磷肥行业多以中、小型企业为主 ,产业能力分散 ,产业集中度低 ,资源利用率差。磷肥行业规模相对较大企业的集中度仅为 49% ,而西方发达国家磷肥产业集中度平均在 95 %左右。全国磷肥企业共 5 0 0多家 ,但装置年生产能力 2 4万t磷酸二铵以上的大型企业只有 18家 ,其他 5 0 0家中、小磷肥企业的平均规模只有万吨上下。加入WTO后 ,我国磷肥工业无一例外将融入“国内市场国际化 ,国际市场国内化”的竞争环境 ;磷肥… 相似文献
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针对胶东地区苹果生产中磷肥用量大、利用率低的问题,通过集成以碳促磷技术、根区局部供磷技术、磷肥分期调控技术和水肥一体化技术,建立胶东地区苹果磷肥减施增效调控技术.对该技术的操作提出了相应的规范,包括磷肥用量、施肥时间、施用方法及配套土壤管理技术,旨在优化胶东地区磷肥根区施用方法,提高磷肥利用效率,实现苹果磷肥减施增效. 相似文献
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设施蔬菜生产体系磷肥用量大、利用率低,土壤磷素淋溶风险高.以设施番茄种植体系为例,划分土壤磷水平指数,明确作物磷肥需求规律,集成启动磷肥技术、磷肥与土壤性质匹配技术、水肥一体化技术及稻壳替代粪肥技术,建立基于根际过程调控的磷肥施用技术,并对该技术的操作性提出了相应的规范,旨在降低磷肥盲目投入,提高磷肥效率,实现设施蔬菜... 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