有机肥料中氮、磷、钾的化学测定方法

介绍了测定有机肥中氮、磷、钾含量的化学分析方法:即用铬粉、盐酸还原,硫酸硝化,氢氧化钠蒸馏测氮。硝酸-高氯酸消解有机肥,待测液用磷钼酸喹啉重量法测定磷,用四苯硼钾重量法测定钾。本方法操作简单,准确度高,适合大批量检验。     

样品加入法在水质分析中的应用

水中铅含量常采用石墨炉法或萃取后火焰原子吸收光谱法测定 ,也有采用共沉淀富集后的方法测定。这些方法 ,要么仪器昂贵 ,要么操作比较麻烦。样品加入法测定水中微量铅含量报道较少 ,采用该方法操作简单 ,测定结果符合要求。1　实验部分1 .1　实验原理在同浓度、同体积的标准溶液中加入不同体积的待测样品溶液 ,测定各溶液的观测值 ,根据加入的体积和测得的观测值 ,采用“最小二乘法”回归求得样品溶液加入体积与总体溶液系列观测值的关系曲线 ,从而求得样品溶液中待测成分的浓度。1 .2　主要仪器与试剂WFX-1 1 0型原子分光光度计 (不带石…     

对有机肥料的化学测定方法探析

文章主要从机肥料氮、磷、钾的含量测定方面出发,针对于普通复混肥料厂在有机肥料的测定中出现测氮的时间过长,没有购置分光光度计和火焰光度计等问题进行阐述。从而采取有效的方法对有机肥料的化学测定,以有利于提高各种化学物的分析水平。     

常规火焰光度法测定复混肥中氧化钾的方法改进

火焰光度法测定复混肥中K2O含量,由于标准溶液与待测溶液基体不一致,使测定结果重现性差,与重量法测定结果相差较大.为此,对方法进行了改进,采用基体一致,用已知K2O含量的复混肥(其氧化钾含量以重量法测定结果为准)作为标准溶液对仪器进行校准.大量的对照实验表明,此法所测K2O结果与重量法测定结果较吻合,且方法简单,快速,...     

电感耦合等离子体发射光谱法测定磷酸中磷的含量研究

电感耦合等离子体发射光谱仪(ICP-OES)通常用于测定微量元素含量,具有检测精度高、可以一次测定大量样品的优点。创新性地将其应用于磷酸中主要元素磷的含量测定,研究了待检溶液的配制方法、检测波长选择,并由此建立了检测方法。通过加标回收、重复性检测验证了方法的可靠性。将该方法与磷钼酸喹啉重量法做对比检测,F检验分析表明这2种方法检测精密度无明显差异。相对于磷钼酸喹啉重量法测定磷酸中的磷含量,ICP-OES方法具有制样简便、一次可测定大量样品、检测速度快的优点,可大大降低检测人员的工作强度、提高检测效率。该方法已制定为贵州省地方标准发布。     

电感耦合等离子体发射光谱法同时测定电子级磷酸中14种杂质元素

磷酸样品直接稀释20倍后,用光谱纯试剂磷酸进行基体匹配,用电感耦合等离子体发射光谱法测定溶液中待测元素特征谱线的强度.建立电感耦合等离子体发射光谱法同时测定电子级磷酸中的钙、钾、镁、铁、锌、铅、砷、铬、铜、锰、钠、铝、钴、锑的方法.研究结果显示.该法测定精度高,各元素的相对标准偏差(RSD,n=11)均<2.0%,加标...     

砷锑钼蓝直接光度法测定含锑样品中的砷

含锑样品中砷的测定,一般需分离锑、砷,手续繁琐,时间长,本法采用浓硫酸溶样,过滤除去大部分锑(Ⅲ)水解沉淀物,得到透明的待测溶液,最后用砷锑钼蓝直接光度法测定砷:即吸取二份待测液,一份不加入硫代硫酸钠的显色液,磷、砷同时显色;另一份加入硫代硫酸钠,将砷(Ⅴ)选择性还原为砷(Ⅲ)后,再加混合显色剂,则仅磷显色,可消除磷的干扰。待测液中所含少量锑和其他常见元素不干扰测定。本法     

肥料中氮、磷、钾的自动分析仪测定法

范围 本标准规定了使用自动分析仪测定肥料中氮、磷、钾含量的方法。本标准适用于肥料中氮、磷、钾含量的测定。     

SN/T 0736.7和GB/T 5874重量法测定复合肥中钾含量结果的差异成因探讨

探讨了SN/T 0736.7 1999与GB/T 5874 2002四苯硼酸钾重量法测定复合肥中钾含量结果的差异显著性和造成显著差异的原因。实验结果表明,空白的扣除和制备样品溶液步骤的不同是造成2种方法测定结果差异的主要原因,沉淀剂浓度对测定结果影响不是太大。     

用氧化锌捕获快速测定添加剂和含添加剂油品中的磷

<正> 磷禽量是石油化工产品的重要质量指标之一。以前用经典的重量法测定,手续繁杂、费时。本文采用氧化锌作捕获剂的比色测磷法,一次平行测定只需约一小时,比国内外的标准方法和其它方法都要简便、快速,磷的相对检出率可达99%以上,并且不受样品中硫、硼、氯、氮、钙、钡、锌、镁、铅等元素的干扰。因此在石油化工产品的生产与研究中都能广泛适用。     

火焰光度法快速测定钾肥中的钾含量

通过优化钾肥样品前处理条件,建立火焰光度法快速测定不同钾肥中钾含量的方法。样品经研磨、加水溶解、加热煮沸、定容、干过滤、稀释后,直接用火焰光度计测定。结果表明,火焰光度法的加标回收率为95.0%~103.0%,RSD为0.18%~0.50%,能够满足分析检测要求。此方法简便快速、准确可靠,可用于钾肥中钾含量的测定。     

肥料养分释放性能快速测试方法研究

研究了一种肥料养分释放性能的快速测定方法。依据"淋溶法"原理设计了淋溶装置,考察了淋溶液流量对肥料氮、磷、钾与养分累积释放率的关系,并采用此装置测试了3种不同肥料的氮、磷、钾累积释放率,与实际效果完全一致。研究表明,采用"淋溶法",通过改变淋溶液流量可以实现肥料养分释放性能的快速检测。     

Optimum phosphate and potassium levels in potato tops

The feasibility of using chemical plant analysis for early diagnosis of phosphate and potassium deficiencies in potatoes was studied. Plant tops (leaves including stems) were sampled from fertilizer field experiments and analyzed for total N, P and K. The inverse relationship between plant N concentration and plant age was used for correcting plant P and K concentration to a standard N content, thus partly eliminating growth stage differences.Maximum tuber yields were associated with leaf P above 0.5% and leaf K above 5%, both at 5% N in DM. With each percent decrease in N concentration the critical value for P decreases by about 0.1% and that for K by about 0.5%. Serious yield reductions may be found below 0.3% P and below 3% K, again at an N-level of 5%.     

Relationship between growth rate,fertilizing and foliar nutrient concentrations forEucalyptus grandis; preliminary investigations

This is a third paper in a series on foliar nutrient concentrations for seedling crops ofEucalyptus grandis. It describes the relationship between foliar nutrient concentrations ofEucalyptus grandis and height growth rate as influenced by fertilizer application and liming in four comprehensive experiments. Tentative optimum levels for the foliar nutrient concentrations of N, P, K, Ca, Mg, S, Zn, Fe, Cu and Mn and some ratios of macro-nutrients are indicated for the growing conditions at these experimental sites as well as their practical value and limitations. In a pooled analysis, 71 per cent of the variation in height growth was explained by the levels and ratios of nutrients and the rate of N and P application. All elements determined except Cu occurred in this prediction equation. The foliar levels of N, P, K and Mn, the N/P ratio and P application appear to be the most important explaining variables.     

Photometric Determination of Indolyl Glucosinolates in Seeds of Rapeseed

For the selection of rapeseed genotypes with reduced contents of indole glucosinolates a method has been developed which allows the determination of these substances with a multichannel photometer. Basis is the reaction with diazotized sulfanilic acid in the presence of o-phosphoric acid. The red coloured coupling product has an absorption maximum at 510nm. From measuring values obtained by this method and by high pressure liquid chromatography a coefficient of correlation of r = 0.90 (N = 20) has been calculated.     

苹果园的测土配方施肥技术

在一定的目标产量区间里,苹果园氮、磷、钾肥的施用量与土壤中氮、磷、钾养分含量呈负的线性关系：根据烟台地区苹果生产实践,总结提出了养分施用量与土壤养分含量、目标产量的线性函数公式,可方便求得苹果的适宜基、追施N、P2O5、K2O量。     

NPK-fertilizer efficiency — a situation analysis for the tropics

This paper examines the efficiency of applied N, P, and K fertilizers under tropical conditions. To meet their food demands, tropical countries are importing large quantities of fertilizers at an enormous cost. There is a need for improving crop yields at a reduced cost and a better understanding of the factors that contribute to the overall efficiency of applied fertilizers. It is estimated that under tropical condition, the efficiency of applied N is less than 50%, less than 10% for P and for K it is somewhere around 40%. Losses of N are mainly due to leaching, runoff and volatile losses of ammonia. Under flooding and in alternate wetting and drying conditions of rice lands and low lands, dentrification and volatile ammonia losses are considerable. The N losses from these soil could be minimized by proper management such as rate, methods and time of application. The coating of urea with S has shown some improvement in increasing efficiency. Nitrification and urea hydrolysis inhibitors can improve fertilizer efficiency in certain situations provided they are properly used. The efficiencies of these inhibitors depend on the nature of the chemical compounds, soil properties, and method of application. Low efficiency of applied P fertilizer is mainly due to retention of P by soil clay fractions and iron and aluminum hydroxides. Even though retained P is not available to the first crop, it is made available to a certain extent to the succeeding crops. The rate and methods of P applications and forms of P determine the efficiency of applied P fertilizers. The use of native rock phosphate along with P fertilizers on acid soils appears to be an attractive alternative in reducing the fertilizer cost. The loss of K in tropical soils is largely attributed to leaching and runoff. To reduce K loss by leaching, it is more advisible to apply K in split doses than a single dose. Liming has a beneficial effect in retention of K and reducing P fixation in acid soils.Senior author formerly was a Research Advisor to EMBRAPA/IICA/World Bank program at National Corn and Sorghum Research Center, Sete Lagos, MG, Brazil.     

舱内装饰性面板涂层的色差控制

介绍了一种利用测色仪进行色差检测及确定最大允许色差范围的方法,并通过此方法进行舱内装饰性面板涂层的色差控制,生产实践证明了该方法的可行性。     

河南省大量营养元素平衡状况

河南省耕地氮、磷、钾化肥投入构成及其演变表明：氮肥所占比例在减少,而磷、钾肥所占比例逐步提高,但仍未达到合理的配比。磷、钾肥仍然不足。根据多年田间试验结果及施肥和农作物产量与携营养物质的统计分析,计算了河南省大量营养元素的平衡状况     

Effect of NPK fertilization on the mineral nutrition and yield of three coconut genotypes

Annual application of NPK fertilizers over a 18 year period to coconut on red sandy loam soils resulted in a minimal increase in mineralisable N, but in a marked increase in available P and K. Plant N levels, however, reflected the improved N nutrition but did not reach sufficiency levels found elsewhere. An available P status of 15 ppm in the control plots kept leaf P at sufficiency levels. P fertilizers did not increase the P content of leaves. K fertilizers raised the K leaf content to sufficiency levels. Doubling the M₁ fertilizer rates of 500 g N, 220 g P and 830 g K per palm per year had no effect on N, P and K levels in the palm leaves.Changes in K levels of the leaves had antagonistic effects on leaf Mg (r = – 0.68^**) and leaf Na (r = – 0.87^**). As this effect brings leaf Mg close to deficiency values palms receiving K might need additional Mg as well.The findings and interpretation of soil and leaf analysis data were confirmed by large yield responses to application of NPK fertilizers. Genetic differences between palms in their response to levels of nutrient supplies were apparent. The CDO × WCT hybrid outyielded the high yielding WCT variety especially when NPK was given at the M₁ level. The response in yield to applied fertilizers was linear for WCT and curvilinear for the hybrids CDO × WCT and WCT × CDO.