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介绍了中科院学部咨询评议项目"我国化肥使用中存在的问题与对策"及香山科学会议第526次学术讨论会"建立绿色的肥料保证体系的关键问题",以了解国内肥料业关注的问题;在国际上普遍关心的是由于长期仅重视氮磷钾的施用而补充的中微量元素不足致使作物品质普遍下降,影响人类健康,作物对自然的抗性降低。介绍了以人类为核心的中微量元素观,及补充能增强作物抗性的中微量元素的重要性。 相似文献
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中微量元素在复肥中的添加工艺与技术 总被引:1,自引:0,他引:1
《化肥工业》2017,(4)
目前,由于高浓度化肥的大量使用,造成了肥料品种结构失衡,土壤中中微量元素缺乏,从而导致土壤污染、农作物品质下降等问题,间接影响了人类的健康。简述了中微量元素的重要性以及中微量元素的来源、形态及有效性,并对复肥中添加中微量元素的工艺与技术进行了初步研究。 相似文献
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今年是中国微量元素科学研究会成立三十周年,从这一跨学科一级学会三十年发展的四个阶段,重点阐述了江苏、湖北、安徽、上海、广东对人体必需微量元素硒、锌、铬在防治地方病、肿瘤、心血管疾病、代谢性疾病和检测方法及基础研究的研究成果,通过对14次全国微量元素学术研讨会的论文总结显示,中国的微量元素研究前景光明。 相似文献
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Coal combustion from power stations is an important anthropogenic contributor of toxic trace elements to the environment. Some trace elements may be emitted in range of valencies, often with varying toxicity and bioavailability. Hence, determination of trace element speciation in coals and their combustion products is important for conducting comprehensive risk assessments of the emissions from coal-fired power stations. This study focuses on speciation of selected trace elements, As, Cr, and Se, in coal combustion products and Hg in flue gas, which were sampled at one Australian power station. Different analytical methods such as secondary ion mass spectrometry (SIMS), ion chromatography-inductively coupled plasma mass spectrometry (IC-ICPMS) and X-ray absorption near edge structure spectrometry (XANES) were used to determine trace element speciation in coal and ash samples. Results showed that As, Cr and Se are all present in a range of valency states in coal. Concentrations of As and Se in the bottom ash as well as the more toxic hexavalent chromium were less than the detection limits. The more toxic As3+ form in fly ash was at 10% of the total arsenic, while selenium was mainly found in Se4+ form. Hexavalent chromium (Cr6+) in fly ash was 2.7% of the total fly ash chromium. Mercury speciation in flue gas was determined using the Ontario Hydro sampling train and analysis technique. Approximately 58% of the total mercury in flue gas was released in the elemental form (Hg0), which, among all mercury species, has the highest residence time in the environment due to lower solubility. This work summarises the performance of the selected analytical techniques for speciation of trace elements. 相似文献
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痕量有机污染物因其在水环境中存在的浓度值极低,造成了监测上的困难,目前对于痕量有机污染物的检测分析主要分包括两个部分:(1)样品前处理;(2)仪器检测。本文主要针对目前监测环境水体中痕量有机污染物浓度常使用的一些样品前处理方法和检测方法进行综述。 相似文献
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食品中痕量硒分析方法研究进展 总被引:1,自引:0,他引:1
硒是一种人体必需微量元素,具有抗氧化和防癌作用。硒主要来源于食品,从食品中摄入硒量过高或过低都会对健康产生较大危害,所以对食品中硒含量的监测已引起人们日益关注。建立简单、快速、准确的分析方法尤为必要。本文对近年来国内外食品中硒分析方法研究进展进行了综述,主要包括分子光谱法、原子光谱法和电化学方法等。 相似文献
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人体内重金属过量会导致各种疾病的发生,对环境和生物样品中的重金属进行分析已经受到人们的广泛关注,发展痕量/超痕量重金属分析方法已成为分析科学家们关注的热点问题之一。文章的目的在于总结现有的痕量重金属分析方法,特别是磁固相萃取技术,并探讨了新型的分析方法的发展趋势与方向。 相似文献
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常量元素与微量元素特征在物源分析中的应用 总被引:1,自引:0,他引:1
沉积物物源分析是研究盆地与造山带关系的重要途径。沉积物的地球化学特征在物源分析中起了非常重要的作用。通过查阅近几年相关文献资料,总结出常量元素与微量元素特征在沉积物物源分析中的主要应用:判断物源区的构造背景与判别沉积物源区物质组成等。地球化学是直观、简捷、实用、有效的分析方法之一。但沉积岩易受其它地质因素影响,在实际研究中,还需结合研究区的地质背景以及综合运用多种方法进行物源区分析。 相似文献
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以电感耦合体原子发射光谱法(ICP-AES)直接同时对低碳铬铁中微量杂质元素Mn、P进行测定,优化了仪器条件,采取加入基体和钇内标校正的方法消除了试液进样的物理化学影响干扰。精密度、标准样品分析对照均取得了满意的结果。 相似文献
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《Fuel Processing Technology》1997,51(3):205-217
Analytical methods for solid samples taken from a coal-fired power plant were developed and optimized in order to facilitate a comprehensive series of measurement campaigns aimed at trace metal balance determinations in various coal-fired power plants. Commercial reference materials with certified trace element contents were used as model samples. A procedure which had been previously developed for the analysis of fly ash was found to give good recoveries in the case of both coal fly ash and coal in a two-laboratory intercomparison. This procedure was based on microwave digestion in a mixture of HNO3 and HF in closed vessels. The digestion of samples of dolomitized limestone and gypsum rock was found to be successful under similar conditions but using a mixture of HNO3, HCl and HF, although the precision of the determination was not as good as in the case of coal and coal fly ash. The digestion procedures developed and tested in this work can be recommended as simple and uniform methods in the analysis of power plant samples for a number of trace elements, exclusive Hg. 相似文献
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介绍在线分析仪在检测半水煤气中微量氧含量中的应用,阐述磁压式氧分析仪的硬件组成、测量原理、以及测量过程中故障的诊断和处理方法。 相似文献
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景德镇历代青花瓷微量元素的研究 总被引:2,自引:2,他引:0
采用中子活化技术,测试了景德镇历代青花瓷胎、釉中的微量元素组成,运用多元统计方法,对样品进行了分析和归类,找出了一批具有判别能力的特征元素,建立了断代判别函数,表明微量元素不权可满足古陶瓷的断源需求,同样有利于古陶瓷的断代研究。 相似文献