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Lei Qingru Yang Juan Li Haila 《保鲜与加工》1988,(5)
Great accuracy can be obtained when metal iron is determined with bromine for dissolution K2Cr2O7 for titration. Unfortunately, harmful substances such as Br2, CH3OH, HgCl2, K2Cr2O7 etc. must be used when this method. But these harmful substances can be avoided when I2-C2H5OH is used for dissolution and EDTA for titration as discussed in this paper. As this method is simple with good reapetability, it is suitable for the diterminat ion of metal iron slag containing V.Ti, in slag containing high Ti, and in common slags. 相似文献
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In this article a method is investigated for the determination of low-valence titanium in slag containing a high titanium content. The residue is dissolved using H2SO4-HF-H3PO4 after tMFe, Fe2O3 and the part of FeO are separated from sample with FeCl3-HCl, and NH4 Fe(SO4)2 is added to oxidate low titanium. Then the standard solution of K2Cr2O7 is used to tit-rat Fe2+ in sample solution. The method possesed with a advantage of simple rapid and good repeatability so that it can be used in the roution determination. 相似文献
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Hcl is used to remove MF4, Fe2O3 and part of FeO. The residue is dissolved by H2SO4-HF-H3PO4. Then, NH4Fe(SO4)2 is added to oxidate low-valence titanium and the standard solution of K2Cr2O7 is used to titrate Fe2+. The amount of total iron minus the amount of iron which has been removed, so that the amount of residue Fe2+ can be adjusted. This method has many advantages such as simplicity, rapidity repeatability. 相似文献
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The following details are discussed in the present paper, after high titanium slag and H3PO4 is put in the closed system,the .reaction takes place under controlled temperature conditions, and the gas produced is collected. The two phases of gas liquid attain kinetic equilibrium, ihe gas above the liquid is used to make GC analysis with the aid of chromatographic column of 5A molecular sieve, TCD and N2 30ml/min. Satisfactory quantitative results can be achieved with simple instruments and uncomplicated operation technique. 相似文献
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本研究运用田间和盆钵试验,观察了甘蓝型油菜(B.napus)角果生长的基本特点,探讨了不同氮水平与角果发育的关系。结果表明,角果生长发育进程呈“S”型曲线,即含明显的生长缓慢期、生长优势期、物质积累优势期和衰老期;氮水平间角果面积增长速率的差异达极显著的正相关(r=0.9091~(**)),单株角果面积与籽粒产量亦呈极显著的正相 相似文献
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玉米C型胞质雄性不育系花粉败育的细胞学研究 总被引:5,自引:0,他引:5
利用光学和电子显微镜对玉米C型胞质雄性不育系和保持系的花药与小孢子发育过程进行对比观察.结果表明,不育系小孢子初始败育发生在幼龄小孢子时期,单核中期基本上完全败育,绒毡层到开花前崩溃.在小孢子初始发育时期,不育系绒毡层细胞的质体呈“杯状”变态.导致雄性不育主要的细胞学原因是绒毡层细胞结构、功能的失常. 相似文献
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重金属污染及其测量方法一直以来都是粮食检测部门关注的重点.本文探索采用微波消解结合ICP-MS的方法同时测定小麦中铅、镉、砷、汞含量,并根据此法测量结果评价了江苏小麦重金属污染情况.结果表明,该方法测试铅、镉、砷、汞含量的相关系数(r2,)分别为0.9991、0.9999、0.9999、0.9997;检测限分别为0.05μg/kg、0.01 μg/kg、0.02μg/kg、0.06 μg/kg;精密度分别为3.7%士2.8%、3.8%士2.8%、2.8%士1.9%、3.7%士3.5%;加标回收率分别为99.5%±4.4%、98.2%±4.6%、100.6%±7.1%、97.9%±10.8%;2014年江苏小麦铅、镉、砷、汞含量未见超标.结果认为,微波消解结合ICP-MS是一种高效、准确的小麦铅、镉、汞、砷含量测定方法. 相似文献
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棉花根系的生长特性及其与栽培措施和产量关系的研究 Ⅱ栽培措施对棉花根系生长的影响及其与地上部和产量的关系 总被引:8,自引:0,他引:8
本文研究了灌溉、施肥量与播种期对露地棉与地膜棉根系的生长特性及其与地上部的相互作用和产量形成的影响。结果表明,生长期灌水处理棉株根系入土浅,总长度减少,未灌水处理根量在深土层明显增加;重肥处理根系入土深,深土层根量增加。灌水及重肥处理根系新根量均增加,根系伤流量增大,生理活力增强。早播棉株主根深度增加,根重增大,尤在生育前期增长明显,同时.根系建成提前,根系分布范围广。灌水、重肥与早播处理棉株根重、地上部重及籽棉产量等均增加。棉株根量与产量间存在显著相关关系,蕾期根量对产量的效应最大。 相似文献