Comparison of Six Trace Elements Content in Two Genuine Medicines of Notopterygium Incisum and Aconitum pendulum in Qinghai plateau

为研究青海高原道地药材羌活和铁棒锤的特性,采用电热板消解法处理样品,原子吸收分光光度法测定了两种药材中Ca、Mg、Cu、Zn、Fe、Mn 6种金属元素的含量.结果表明,Ca、Mg、Cu、Zn、Fe、Mn 6种微量元素含量在两种道地药材中,含量最高的是Ca,平均值分别为(55.78±12.10) mg/g和(26.48±5.79) mg/g;含量最低的元素为Cu,其值分别为(0.28±0.28)mg/g和(0.09±0.06) mg/g;其它元素含量从高到低依次为Mg,Fe,Zn,Mn.可见不同地区的羌活其微量元素的含量有明显的差异,且羌活微量元素含量也存在种间差异,细叶羌活的Ca、Mg元素含量比宽叶羌活的要低,相反,Fe,Cu,Zn 3种元素含量细叶羌活的比宽叶的要高.     

青海高原道地药材羌活和铁棒锤微量元素含量比较研究

为研究青海高原道地药材羌活和铁棒锤的特性,采用电热板消解法处理样品,原子吸收分光光度法测定了两种药材中Ca、Mg、Cu、Zn、Fe、Mn 6种金属元素的含量。结果表明,Ca、Mg、Cu、Zn、Fe、Mn 6种微量元素含量在两种道地药材中,含量最高的是Ca,平均值分别为(55.78±12.10)mg/g和(26.48±5.79)mg/g;含量最低的元素为Cu,其值分别为(0.28±0.28)mg/g和(0.09±0.06)mg/g;其它元素含量从高到低依次为Mg,Fe,Zn,Mn。可见不同地区的羌活其微量元素的含量有明显的差异,且羌活微量元素含量也存在种间差异,细叶羌活的Ca、Mg元素含量比宽叶羌活的要低,相反,Fe,Cu,Zn 3种元素含量细叶羌活的比宽叶的要高。     

微波灰化-电感耦合等离子体原子发射光谱法测定原油中的金属元素

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。     

电感耦合等离子体原子发射光谱法测定紫斑牡丹胚乳和胚中矿物质元素

为了给离体体细胞胚的人工胚乳配制提供矿物质元素种类和数量方面的参考,用浓硝酸-高氯酸(4∶1)的混合溶液消解紫斑牡丹的胚乳和胚样品,采用电感耦合等离子体-原子发射光谱法(ICP-AES)测定了样品中的(K、Na、Ca、Mg、Fe、Cu、Zn、Mn、Li、Ni、B、Ag、Cd、Pb)14种矿物质元素含量。结果表明:各元素的校准曲线的回归系数在0.9990～0.9999之间,线性良好;方法精密度高,能多元素同时分析;紫斑牡丹胚乳和胚中均含有植物生长必需的K、Ca、Mg 3种大量元素,Fe、Mn、Cu、Zn、Ni、B 6种微量元素,1种有益元素Na,及Li和Pb,Ag、Cd则未被检测到。在被检测到的12种元素中,Mg、Zn、Mn、Fe、K、Na、Li与Ni 8种元素在胚乳中的含量低于胚中的含量,Ca、Cu、Pb与B在胚乳中的含量则高于胚中的含量。     

微波辅助消解ICP-AES法测定几种血藤中17种元素*

目的 建立电感耦合等离子体发射光谱(ICP-AES)法测定血藤类中药中K、Ca、Mg、P、Sr、Fe、Mn、Zn、Cu 、Co、Cr、Al 、Ba、Ni、As、Pb和Cd17种常量和微量元素含量的测定方法。方法 采用微波辅助消解样品,电感耦合等离子体发射光谱(ICP-AES)法测定几种血藤中17种元素的含量。 结果 该方法的检出限为0.00003~0.00981μg/mL,回收率88.37% ~110. 00%,相对标准偏差( RSD) 均小于5.0%。结论 该方法可快速、灵敏、准确测定血藤类中药中多种常量、微量元素的含量。血藤样品中除含有人体必需的常量元素K、Ca、Mg外,还含有Fe、Zn、Mn、Cr、Co等必需的微量元素和其它元素P、Ni、Ba、Al、Sr、Pb、Cd、Ba等。     

微波辅助消解-电感耦合等离子体原子发射光谱法(ICP-AES)测定几种血藤中17种元素

建立电感耦合等离子体原子发射光谱法(ICP-AES)测定血藤类中药中K,Ca,Mg,P,Sr,Fe,Mn,Zn,Cu,Co,Cr,Al,Ba,Ni,As,Pb和Cd 17种常量和微量元素含量的分析方法。样品用微波辅助消解,ICP-AES法检测几种血藤中17种元素的含量,方法的检出限为0.000 03~0.009 81μg/mL,加标回收率88.37%~110.00%,相对标准偏差(RSD)均小于5.0%,方法可快速、灵敏、准确测定血藤类中药中多种常量、微量元素的含量。血藤样品中除含有人体必需的常量元素K,Ca,Mg外,还含有Fe,Zn,Mn,Cr,Co等必需的微量元素和其它元素P,Ni,Ba,Al,Sr,Pb,Cd,Ba等。     

金樱子茎根中必需微量元素的测定

为测定和分析金樱子茎、根中的微量元素种类及含量,采用酸式(HNO3-H2O2)微波消解法处理样品,原子吸收分光光度法测定了金樱子根茎中的微量元素,统计学处理数据。结果表明,在自采茎、根中各种元素含量(单位均为μg/g)分别为:Cu(1.713±0.156),(1.857±0.191);Zn(204.541±5.377),(432.209±4.874);Ca(2 596.875±68.337),(1 554.541±42.743);Mg(429.041±19.740),(663.750±23.867);Mn(18.604±0.285 5),(14.304±0.884);Cr(1.672±0.079),(3.561±0.079);Ni(0.896±0.068),(0.488±0.025);Fe(60.900±0.651),(70.221±1.328);Co(0.758±0.068),(0.662±0.057)。茎与根比较有显著差异的是Ca、Cr、Ni、Mg、Zn。结论:金樱子茎根含有丰富的必需微量元素,但不同部位之间某些微量元素的含量存在一定差异。     

火焰原子吸收光谱法测定黄花菜根中微量元素含量

采用火焰原子吸收光谱法测定了黄花菜根中Ca、Fe、Zn、Cu、Mn、K和Mg 7种金属元素含量.结果表明,在常量元素中K、Ca含量较高,微量元素中Fe、Cu含量较高,7种金属元素含量由高到低顺序分别为:K、Ca、Mg、Fe、Cu、Zn、Mn.加样回收率为98.75％～106.25％,该法操作简单、结果准确,是黄花菜根中...     

苏州荠苧总黄酮与微量元素含量的测定

采用分光光度法测定了苏州荠苧的总黄酮含量;采用了等离子发射光谱法测定了其元素含量.结果表明,苏州荠苧总黄酮的含量分别为55.31 mg/g(7月采收)、65.00 mg/g(8月采收);含K、Ca、Mg等多种常量元素;含Cu、Fe、Mn、Zn、Cr、Co等多种人体必需的微量元素,其中Fe含量最高;而有害重金属元素Hg未检出,Pb和As的含量均较低(小于药典规定量).可见8月采收的苏荠苧总黄酮含量较高,苏州荠苧含多种人体必需的微量元素,有害重金属含量低,具有较大的开发价值.     

传统藏药材高原香薷的矿质元素分析

对传统藏药材香薷中高原香薷种的17种微量元素进行了分析。结果表明,在高原香薷中人体必需微量元素Cu、Zn、Fe、Mn、Co、Ni、Se等含量较高,尤其以Cu、Fe、Mn元素的含量为高。Na、Ca等宏量元素含量亦较高。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.