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对火焰原子吸收法测定复合肥中钾元素含量的各种工作条件进行了探索研究.该方法选择钾元素的次灵敏线404.4 nm作为测定波长,并采取在试液中加入一定量的消电离剂氯化铯以有效抑制钾在乙炔-空气火焰中的电离,从而提高了样品测定数据的准确度和精密度,具有操作简单、检测快速等优点.与重量法相比,该方法具有明显的优势,适合于大批量... 相似文献
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用高压罐硝化法,以正交试验原理处理样品,利用ICP—AES法测定雪里蕻茎、叶中Mg、Zn、Fe、Ca、Se、K、Cu、Co、P、Mn共10种微量元素的含量。方法回收率在96.00%~103.25%之间,相对标准偏差小于1.66%。ICP—AES法具有灵敏度高、方便、快速等优点,且同时测定多种元素,更适合雪里蕻中非金属与金属元素的分析测定。实验证明,雪里蕻中含有Mg、Zn、Fe、Ca、Se等大量对人体有益的微量元素。同时比较了雪里蕻的茎及其叶中微量元素含量,为雪里蕻的开发提供理论参考。 相似文献
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报道了用笑气-乙炔火焰原子吸收光谱法测定氟石中氧化铝。试样经氢氟酸处理、高氯酸冒烟后,加入盐酸和硼酸温热溶解残渣。用富燃笑气乙炔焰在分析线A1309.3 nm处,测定铝的吸光度。试验了溶样酸和酸度、硼酸、基体钙及共存元素对测定的影响。校准用的标准溶液系列中加入相同量的钙和硼酸作基体匹配。方法回收率96%~105%。本方法准确度、精密度满足商品检验的要求,已用于出口氟石的检验。 相似文献
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用火焰原子吸收光谱法(FAAS)测定蒙古奶茶中的微量元素钙、镁、锌。对测定条件、干扰因素、准确度和精密度进行了考察。用灰化法处理蒙古奶茶。对3种元素进行测定,结果表明,吸光度与浓度之间呈良好线性关系,钙、镁、锌回归方程分别为:A=0.1334C+0.0025(R2=0.9993),A=0.4838C+0.0311(R2=0.9998),A=0.2149C+0.0224(R2=0.9997)。3种不同的蒙古奶茶中的钙、镁、锌测定结果的RSD值均小于1.25%,回收率在95.0%~105.0%。 相似文献
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Rheological and fire properties of a composite of unsaturated polyester resin and halogen‐free flame retardants
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The main subject of the present research is to determine the impact of flame retarding fillers on macroscopic properties of composites. The effect on rheological properties of composition unsaturated polyester resin (UP) and flame retardant blend (FR) consisting of expandable graphite (EG) and or not modified silica and: (1) melamine polyphosphate (MPP) with ammonium polyphosphate (APP), (2) MPP with aluminum trihydrate (ATH), (3) only MPP was examined. Next, their influence on thixotropic properties of UP was estimated. FR fillers were compared according to their grain size, specific surface, and shape factor. Rheological properties were determined by applying hysteresis loop surface and thixotropy factor measuring. For the UP + FR composition, the dependence of grain morphological parameters, such as shape factor and specific surface, on viscosity and hysteresis loop surface was determined experimentally. All of the tested composites consisting of UP + 40% FR blend exhibits high flame resistance. An addition of only 2% of modified silica to all of the FR blends caused significant enlargement of hysteresis loop surface and thixotropy index. Hence, for the next stage of the research (an industrial test of GRP pipes casted by the centrifugal method) FR blend without modified silica was chosen. A composite consisting of UP, MP, APP and EG is characterized by lower heat release rate (HRRmax) (ca. 83%) and lower TSR (ca. 80%), ALMR (55%), and MARHE (73%) in comparison to UP resin; and that UP + FR composition exhibit satisfactory rheological properties as well. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44371. 相似文献