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1.
藏药材白花龙胆花中微量元素的分析   总被引:2,自引:0,他引:2  
对藏药材白花龙胆花中17种微量元素(Cu、Zn、Fe、Mn、Co、Ni、Se、Cr、Mg、Ca、K、Na、P、As、Hg、Pb、Cd)的含量作了测定。结果表明,白花龙胆花中含有较高的人体必需微量元素和常量元素,其中常量元素K、Ca、Na、Mg和微量元素Zn、Fe、Mn的含量均较高。  相似文献   

2.
南药巴戟天中十二种无机元素的初步研究   总被引:2,自引:0,他引:2  
采用火焰原子吸收光谱法测定了不同产地和生长期的巴戟天中Mn.Fe.Cu.Zn、Ca、Mg、K、Na、Cr、Co、Ni、Pb等十二种无机元素的含量及其灰化率,为研究巴戟天的药效及栽培技术提供了实验数据.  相似文献   

3.
松口蘑中微量元素的测定   总被引:1,自引:0,他引:1  
采用火焰原子吸收法同时测定了松口蘑中K、Ca、Na、Mg、Fe、Pb、Cd、Co、Cr、Zn、Mn、Cu等12种元素的含量。方法的相对标准偏差在0.08%-2.32%范围,回收率在97.1%-108.3%范围。结果表明,在三种松口蘑样品中,除含有较高的K、Na、Ca、Mg和一定量的有害元素Cd、Pb外,其余6种对人体有益的微量元素较为丰富。  相似文献   

4.
采用微波消解样品,运用电感耦合等离子体原子发射光谱法同时测定山药中K,Na,Ca,Mg,Zn,Fe,Cu,Mn,Se,Pb,Cd和Cr 12种元素。结果表明:方法简便、快速、准确;山药富含对人体有益的K,Ca,Fe,Mg,Zn,Mn,Se等矿物质元素,其肉质中重金属元素Pb,Cd,Cr含量均未超过国家食品卫生标准。  相似文献   

5.
采用ICP—AES法同时测定黑豆和红小豆中Na,Sn,Ca,Zn,Cu,Mg,Al,Fe,P,K,Si,Se,Ba,Mn,M015种元素含量,并对各元素进行了加标回收实验,黑豆和红小豆中各元素的平均回收率在93.11%~102.15%,相对标准偏(RSD)在0.83%0~2.8%,检出限介于0.11~14.09Fg/L。建立了简便、快速、准确和稳定的测定黑豆和红小豆中元素的测定方法。结果显示在黑豆和红小豆中K,Ca,P,Mg,Mn,Fe,Zn等常量元素和微量元素含量较高。红小豆中Ca,Mg,Fe,Zn等营养元素的含量较黑豆中的高。  相似文献   

6.
火焰原子吸收光度法测定维药芜菁的微量元素   总被引:1,自引:0,他引:1  
为探讨微量元素与芜菁的药效关系,用火焰原子吸收分光光度法测定了维药芜菁中的K,Na,Ca,Fe,Cu,Co,Zn,Mn,Mg等9种元素含量。结果表明,芜菁含有丰富的人体必需微量元素,其中K,Na,Ca,Zn的含量更显著;方法的回收率在93.7%~102.5%之间,RSD值在0.39%-1.3%之间,能用于维药芜菁中多种微量元素的同时测定。为芜菁的进一步研究和综合开发利用提供了新的科学依据。  相似文献   

7.
采用微波消解样品,运用电感耦合等离子体原子发射光谱法同时测定山药中K、Na、Ca、Mg、Zn、Fe、Cu、Mn、Se、Pb、Cd和Cr等12种元素。结果表明:方法简便、快速、准确度高;四种山药均富含对人体有益的K、Ca、Fe、Mg、Zn、Mn、Se等矿物质元素,其肉质中Pb、Cd、Cr含量均未超过国家食品卫生标准。  相似文献   

8.
采用微波消解-火焰原子吸收光谱和原子荧光光谱法对藤茶中Fe、Na、Zn、Pb、Cr、Co、Ca、Mg、Cd、As等16种微量元素进行了分析测定。该测定方法的回收率在96%~101%之间,相对标准偏差(RSD)小于5%。结果表明,藤茶中富含Ca、Mg、Fe、Mn、K、Na、Cr、Zn等对人体有益的微量元素,同时还含有微量的有害元素Cd、Pb、Sb,没有发现As和Hg。  相似文献   

9.
分析了青藏高原北麓河地区29种高寒植物15个元素含量的特征。结果表明,这些植物中元素平均含量>400μg/g的元素有Ca,Mg,Na,K,Fe,10~100μg/g的有Mn,Cr,Zn,Cu,<10μg/g的有Ni,Co,As,Pb,Cd,Hg;种间同种元素的含量变化规律不统一。相关性分析表明,Cu与Cd,Fe与Cd和Hg,Cr与Ni,Co和Mg极显著正相关,Cr和Ca极显著负相关;聚类分析表明,Na,As元素对本区植物聚类的影响最大,莎草科、禾本科、菊科科内植物元素含量相似。  相似文献   

10.
三七生长初期不同部位微量元素的含量测定   总被引:6,自引:1,他引:6  
采用电感耦合等离子体发射光谱法(ICP-AES),对文山地区GAP种植及农户常规种植的生长初期三七不同部位中的微量元素Mg、P、Ca、Mn、Na、Fe、Co、Cu、Zn、Mo、Cr、Ni、Ge、Se等14种元素进行了测定分析。结果表明,三七的根、茎、叶中含有丰富的人体必需Mg、P、Ca、Mn、Na、Fe、Co、Cu、Zn、Mo、Ge、Se等有益元素,且P、Ca、Mg、Fe含量较高,Na、Mn、Co、Zn次之,Co、Mo、Cr、Ni、Ge、Se含量均较低。为三七GAP栽培标准和特征制订、三七道地药材的化学特征——化学指纹图谱的建立及研究提供理论依据。  相似文献   

11.
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%.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
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.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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