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1.
ICP-AES法测定锌阳极中的铝、镉、铁、铜、铅   总被引:2,自引:0,他引:2  
通过分析高频功率、雾化压力、辅助气流量和泵速等试验条件,建立了ICP-AES法测定锌阳极中铝、镉、铁、铜、铅的方法。用该方法测定锌阳极中的铝、镉、铁、铜、铅,其RSD分别为0.17%、0.63%、2.7%、5.2%、2.5%,回收率分别为99.3%-101.2%,99.3%-100.3%、97.1%-102.2%、97.8%-102.9%。对锌阳极试样进行测定,该方法的测定结果与GB4951-85方法的测定结果基本一致。  相似文献   

2.
采用沉淀、给 合滴定法,间接快速地测定了重晶石中钡的含量。对重晶石熔样方式、络合反应条件及共存干扰离子的消除方法进行了研究。该方法快速、准确,加收率为98.5%-100.7%,RSD小于2.48%。  相似文献   

3.
高效液相色谱串联质谱法测定血清中内美通   总被引:5,自引:0,他引:5  
研究了高效液相色谱串联质谱联用测定人血清中内美通的方法。用乙醚提取血清中的内美通,米非斯酮做内标,电喷雾离子化,选择内美勇母、子离子对m/z309-m/z241;内标的母、子离对对m/z430-m/z372;串联质谱采用多反应扫描监测方法,定量测定人血清的内美通。该方法测定速度快,灵敏度高,选择性好。方法的标准曲线线性范围3.5-177μg/L(r^2=-0.999);检出限0.8μg/L;进行6次平行测定,日间RSD=2.3%-13.7%,RD=4.8%-3.0%;日内RSD=5.5%-14.8%,RE=3.1%-6.7%;回收率内美通是91.0%,内标米非斯酮是90.6%。4min完成一个样品测定。  相似文献   

4.
用微波消解和灰化法对蒙成药壮西六味散进行预处理,并用电感耦合等离子体原子发射光谱(ICP-AES)法同时测定了15种常量、微量及重金属元素的含量,进行了加标回收实验。结果显示,壮西六味散中Ca、P和K的含量较高,富含Mg、Na等营养元素,Pb、Cd等重金属含量均低于国家标准;灰化法和微波消解法两种预处理方法对测定结果基本一致。相对标准偏差(RSD)在1.6%-3.5%,加标回收率为95.5%-103%。方法简便准确、选择范围广、可高效快速准确测定壮西六味散中各元素含量。  相似文献   

5.
顶空气相色谱法测定秦龙苦素中的残留溶剂   总被引:7,自引:0,他引:7  
汤桦  雷根虎  李鹏  孔祥虹  何学文 《色谱》2003,21(2):178-180
采用顶空气相色谱法对秦龙苦素中残留的苯、甲苯、对二甲苯、正己烷等有害物质进行分析,并讨论了流速、柱温、平衡温度、平衡时间、抽样次数等因素对测定的影响。分析结果表明,该方法对上述4种有害物质的检测限范围为3-98 μg/L,测定结果的相对标准偏差为0.59%-2.64%,样品的回收率为97.2%-120.0%。方法简便、快速、灵敏、重现性好。  相似文献   

6.
采用高频红外吸收法测定了氧化钴粉中硫的含量,并对样品作测定前的预处理(物理处理),在测定上选用复合型助熔剂,解决了高频感应炉中因顶吹氧气流的作用而导致的样品喷溅问题,并将镍作为辅助助熔剂应用于碳硫测定。该方法可准确测定硫含量为0.001%-0.1%的氧化钴粉中的硫,回收率为95.6%-104.8%。RSD为2.2%-4.9%。  相似文献   

7.
尿酸-铁氰化钾-鲁米诺化学发光测定亚硝酸盐   总被引:6,自引:0,他引:6  
高岐 《分析化学》2002,30(7):812-814
在酸性介质中,亚硝酸盐氧化亚铁氰化钾为铁氰化钾,利用尿酸-铁氰化钾-鲁米诺化学发光体系,建立了一种间接测定亚硝酸盐的新方法。讨论了酸度、反应物浓度、干扰离子等因素的影响。方法的检出限为0.05μg/L,对样品进行了平行测定(n=11),其相对标准偏差为1.8%-3.2%,线性范围为0.001-10ng/L。方法简便,易于操作,并具有较高的灵敏度和选择性。用于环境水样及食品中亚硝酸盐的测定,回收率为95.7%-105.8%,结果令人满意。  相似文献   

8.
原子荧光光谱法测定多金属矿标准样品中的砷、汞、铋   总被引:3,自引:1,他引:3  
采取减少试样反应量及必要的分离手段,以原子荧光光谱法测定基体成分复杂、待测元素含量差异较大的多金属矿标标准样品中的砷、汞、铋,砷、汞、铋的检出限分别为0.2、0.01、1.3ng/mL,测定结果的相对标准偏差分别为1.88%-4.04%、2.1%-5.8%、1.1%-8.9%,线性相关系数均大于0.9970。标准样品的测定结果与推荐值基本吻合。该方法具有简单、快速、准确、精密度好等优点。  相似文献   

9.
离子色谱法测定电厂炉管垢样中的Cl-、SO42-   总被引:2,自引:0,他引:2  
介绍离子色谱法测定电厂炉管垢样中腐蚀介质Cl^-和SO4^2-的方法,并对使用在线淋洗液发生器与以前配制淋洗液的方法进行了对比,提出了其在应用中的特性。垢样中Cl^-和SO4^2-的相对标准偏差分别为2.7%和2.3%,回收率分别为89.0%-97.8%和91.0%-98.9%。  相似文献   

10.
利用Cu^2 和Cr^3 的协同催化作用,促进间苯二酚与唾液酸的显色,再用乙酸丁酯——正丁醇萃取有色物质,变换波长至625nm处测定;血清中的唾液酸含量。建立了血清中唾液酸测定的新方法,方法的线性范围为0-1000mg/L,检出限为2.1mg/L,相对标准偏差为1.59%-2.11%,回收率为96.2%-101.2%,糖类及抗坏血酸等物质对测定的干扰<2%。该法简单、快速、灵敏、准确,可用于临床体液中唾液酸的测定。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
19.
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   

20.
(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   

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