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采用微波灰化技术消化原油样品,并使用电感耦合等离子体原子发射光谱法(ICP-AES)测定其中Na、Mg、Ca、Fe、V、Ni和Cu的含量。探讨了原油样品中金属元素测定的称样量和微波灰化程序,并优化了仪器工作参数和实验条件。样品经微波灰化处理后,用盐酸溶解残渣,方法对Na、Mg、Ca、Fe、V、Ni和Cu元素的检出限分别为0.07、0.01、0.01、0.01、0.02、0.04和0.03mg/kg,回收率在84.5%~96.6%之间,相对标准偏差在2.1%~6.9%范围。方法简便、可靠,可用于原油中Na、Mg、Ca、Fe、V、Ni和Cu 7种金属元素的检测。 相似文献
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原油样品(5 g)于石英坩埚中,放入微波灰化炉中在800℃灰化1h,残渣加入盐酸(1+1)溶液溶解并蒸发至近干,转入50mL容量瓶加水定客后,供电感耦合等离子体原子发射光谱法测定原油样品中微量金属元素铁、钠、镍、钒和钙的含量。方法用于分析原油样品,所得相对标准偏差(n=6)在2.2%~6.5%之间,回收率在92.0%~108.4%之间。测定结果与常规灰化法测定结果对比,经t检验(α=0.05),无显著性差异。 相似文献
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电感耦合等离子体原子发射光谱法测定阳离子交换树脂中15种金属元素 总被引:1,自引:0,他引:1
提出了电感耦合等离子体原子发射光谱法(ICP-AES)测定阳离子交换树脂中15种金属元素含量的方法,优化了样品处理时灰化温度和ICP-AES测定条件,方法的检出限(3s)为0.2~210.0μg.L-1之间。分析了西安脉冲堆一回路系统将使用的新的和已使用的废阳离子交换树脂中15种金属元素含量,加标回收率在87.3%~102.2%范围内。利用所得结果,比较了新、废阳离子交换树脂中金属元素含量的差别,初步分析了西安脉冲堆一回路水系统中金属元素的来源。 相似文献
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《广东微量元素科学》2015,(12)
目的运用火焰原子吸收光谱法对瑞昌山药中的Fe、Zn、Cu、Mg、Ca和Mn 6种金属元素进行测定。方法用浓HNO3湿法微波消解山药样品,采用原子吸收分光光度计测定样品中上述6种金属元素的含量。结果瑞昌山药中含有丰富的所测金属元素。加标回收率在90.0%~109.5%之间,样品相对偏差小于5%,满足测量的要求。结论瑞昌山药中金属元素可作为人体元素的重要补充。 相似文献
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火焰原子吸收光谱法测定煤及煤基活性炭中微量金属元素 总被引:3,自引:0,他引:3
王建程 《理化检验(化学分册)》2009,45(1)
提出了火焰原子吸收光谱法测定煤及煤基活性炭样品中微量元素铜、锌、锰、铁、钙、镁、锡的方法,煤及煤基活性炭样品研磨成粉末状后,按GB 212-1991标准方法规定的灰化条件将样品灰化,灰化样品用高氯酸、氢氟酸溶解后,再经盐酸(1+1)溶液溶解,过滤,按仪器工作条件测定.按标准加入法做回收试验,测得回收率在96.7%~100.9%之间.对7元素分别做精套度试验,求得相对标准偏差(n=6)均小于1%. 相似文献
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用非完全消化法处理杜仲叶,在低温下用浓硝酸消解样品,加入乳化剂Triton X-100(OP)溶解消化过程中所产生的油脂,获得均匀的样品乳浊液,取适量的乳浊液制成试液,用火焰原子吸收光谱法快速测定了样品中的微量元素,并对检出限、加标回收率进行了测定。结果表明,相对标准偏差小于2.1%,测定结果与灰化法一致,且相对误差小于±1.8%。用非完全消化法结合火焰原子吸收光谱法对杜仲叶进行预处理取代灰化法是可行的,且方法简便、准确。 相似文献
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目的使用微波消解和热酸溶液直接溶解板蓝根颗粒,运用火焰原子吸收光谱法测定这两种溶液中Fe、Zn、Cu、Mg、Ca和Mn 6种金属元素的含量。方法分别采用浓HNO3湿法微波消解和直接溶解板蓝根颗粒样品,用原子吸收分光光度计测定上述样品中6种金属元素含量。结果所测定的板蓝根颗粒中含有丰富的金属元素,两种前处理方法测定的结果相差很小。采用此法回收率在92.0%~110.0%之间,样品相对偏差小于3%。结论板蓝根颗粒中金属元素可作为人体元素的重要补充。 相似文献
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目的运用火焰原子吸收光谱法测定中药草珊瑚叶中的Fe、Zn、Mg、Ca、Cu 5种金属元素的含量。方法用浓HNO3-HCl O4消解样品,采用标准曲线法测定其5种金属元素含量。结果所测的样品中含有丰富的人体必需微量元素。方法回收率在99.35%-103.30%之间,样品相对偏差小于5%。结论该法简单、准确,结果令人满意。 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
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用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
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Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT). 相似文献
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George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine. 相似文献