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1.
用ICP-AES法测定心肌梗塞病人和健康人血中18种元素含量,把测量得结果进行显著性t检验和各元素相关关系的分析,获得不同分类组的相关关系。用模式识别的非线性映技术对实验数据进行多元分析,得二维映射平面图,判别率达88.5%-100%。  相似文献   

2.
冠心病(心肌纤维化)微量元素谱的多元分析   总被引:1,自引:2,他引:1  
用ICP-AES分析了冠心病中心肌纤维化男、女患者血液中的19种元素含量,结果通过因子分析得到男女不同性能别的判别元素谱、应用非线性映射得以二维空间图、男性分辨率达96.6%,女性达87.3%。  相似文献   

3.
700例儿童发中锌钙镁铁铜的测定结果及统计分析   总被引:3,自引:0,他引:3  
用原子吸收分光光度法测定了700例学龄儿童中发锌,钙,铜,镁,铁等五种元素,对缺锌情况以及互相间的相关关系进行统计分析,结果表明我国儿童缺锌比例较大,尤其在4周岁以下的儿童缺锌比例大约占65%~86%,Zn与钙,镁有很好相关,这提示单纯对缺锌儿童补锌的方法并不有利。  相似文献   

4.
成人血清元素相关性及比值分析   总被引:3,自引:1,他引:2  
用ICP-MS法测定了79例成人血清14种元素水平,并进行了相关分析。结果提示,多种元素间存在显著正相关;分析了部分元素的比值,为相关研究提供了参考范围,且对元素比值的离散程度进行分析,为多元素关系研究提供了新的线索与依据。  相似文献   

5.
西安地区成年健康人群血清中微量元素正常值研究   总被引:4,自引:0,他引:4  
用随机抽样的方法对西安地区436名健康人血清中Zn、Fe、Cu、Mn、Pb、Cd、Cr、Ni、Mo和Se十种微量元素正常值进行石墨炉原子吸收光谱法测定,并用ST286型计算机进行多因素相关分析和统计处理.结果表明,血清Zn、Cu分布比较集中,其它元素变异度比较大;多数元素与年龄呈相关关系。其中Zn、Cu、Fe、Mn、Pb、Se与年龄呈正相关 而Mo则与年龄呈负相关;多数元素含量与地城环境中徽量元素的分布有明显的相似性.总之,不同地区不同性别和不同年龄段血清微量元素有显著的差异.  相似文献   

6.
对100例皮肤病患者发样中的Zn、Cu、Fe、Ca及Mg五种元素进行了检测,采用主成分分析及因子分析法对分析数据进行了统计学处理,探索皮肤病与该五种元素的关系,结果表明:Zn、Mg元素水平是皮肤病的重要样本特征,其中Mg元素是皮肤病的一个重要影响因子。其水平偏高及偏低者占病例数的92%;Cu、Fe元素水平基本正常;缺Zn影响则不是主要因素,低Zn者只占8%。可将皮肤病分为两大类:(1)Zn、Mg元素水平偏高类;占病例数的58%。(2)Ca、Mg元素水平偏低类,占病例数的32%。  相似文献   

7.
介绍对10种GSS系列土壤及沉积物标准物质中多种元素进行定值的方法和结果,采用模拟土壤元素天然组成比值的校正溶液,对元素间的基体干扰具有明显的抑制作用,利用115In-103Rh双内标元素校正系统,可有效地抑制分析信号的动态漂移,建立了电感耦合等离子体质谱法对土壤及沉积物标准的物质中多种元素定值的方法,用该方法对GSS-4,GSS-5,GSS-8及GSD-9共4种土壤标准物质进行测定,绝大部分元素的测定结果与标准值的相对误差小于10%,相对标准偏差小于10%,对GSS-10-GSS-16,AMS-1,BEM及DMS-1共10种土壤及沉积物待定值标准物质进行定值,绝大部分元素测定结果的相对标准偏差小于10%。  相似文献   

8.
高纯钨酸钠中痕量杂质元素的共沉淀分离和ICP—AES测定   总被引:2,自引:0,他引:2  
提出了以氢氧化镧为共沉淀剂,对高纯钨酸钠中痕量金属杂质元素(钙,镉,钴,铜,铁,锰,镍,锌)进行了共沉淀分离富集后以ICP-AES法进行测定的方法,pH12时,用10g.L^-1镧溶液6ml进行两次共沉淀,能使杂质元素定量分离回收,钨酸钠残留量降至很低水平,试样测定结果表明,各元素回收率在92.4%~104.8%之间,相对标准偏差为1.8%~6.9%。  相似文献   

9.
稀土化合物中Cl-的ICP-MS测定   总被引:4,自引:0,他引:4  
研究了用ICP-MS法测定稀土化合物中Cl^-1。对分析线,内标元素和基体浓度进行了合理选择。方法的加标回收率在80%-125%。相对标准偏差在6.24%-14.70%,测定下限为0.005%。  相似文献   

10.
提出了用浓硝酸沉淀并分离大量基体钼,ICP-AES同时测定钼酸铵中14个杂质元素的方法,考虑了钼基体、酸度、谱线干扰及背景影响等情况。在未引入其它任何试剂的情况下,用硝酸既除去了大量的钼基体,又调整了溶液的酸度,用标准加入法测定钼酸铵中的杂质元素,无需加入高纯基准试剂进行基体匹配,有效降低了分析成本,又消除了由于忽略基准物质中杂质元素的含量给分析测定带来的误差。回收率在85%~112%之间。  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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