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原子吸收法对藏草药川木香中12种元素的初级形态分析 总被引:2,自引:0,他引:2
用原子吸收分光光度法,测定了产于青藏高原的藏草药川木香的全药材、水提液、醇提液中12种元素(Cr、Cu、Fe、Mn、Ni、Se、Zn、K、Ca、Mg、Cd、Pb)的含量,以及水提液中各元素可溶态、水溶态的含量,同时采取正辛醇-水分配体系模拟藏药水提液中各微量元素在人体胃肠中的分配情况,对藏药中微量元素的初级形态进行了分析,初步探讨了酸度变化(人体胃肠酸度)对微量元素的影响,结合藏药药效讨论其相关性,为进一步研究微量元素与藏药药性、药效的关系提供科学的依据和奠定基础. 相似文献
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用原子吸收光谱法,对产于青藏高原的藏草药水母雪兔子和多刺绿绒蒿,测定了全药材、水提液、醇提液中12种元素(Cr、Cu、Fe、Mn、Ni、Se、Zn、K、Ca、Mg、Cd、Pb)的含量,以及水提液中各元素可溶态、水溶态的含量,同时采取正辛醇-水分配体系模拟藏药水提液中各微量元素在人体胃肠中的分配情况,对藏药中微量元素的初级形态进行了分析,初步探讨了酸度变化(人体胃肠酸度)对微量元素的影响,结合藏药药效讨论其相关性,为进一步研究微量元素与藏药药性、药效的关系提供科学依据. 相似文献
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目的研究藏药材铁棒锤的微量元素含量。方法使用电感耦合等离子体质谱仪(ICPMS)测定藏药材铁棒锤药材中As、Hg、Pb、Cd含量,使用原子吸收光谱仪(火焰法、石墨炉法)测定药材中Zn、Mn、Cr、Fe、Ca、K、Cu元素的含量并进行分析。结果铁棒锤中有害元素As、Hg、Pb、Cd含量较低,Cu、Fe等有益元素含量较高。结论藏药材铁棒锤有丰富的微量元素,具有较高的开发利用价值。 相似文献
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系列甘露糖醛酸寡糖的制备与鉴定 总被引:1,自引:0,他引:1
用酸降解法制备了系列甘露糖醛酸寡糖(聚合度2~8),并分析测定了寡糖的结构. 褐藻胶经部分酸水解,于pH=2.85处分级获得聚甘露糖醛酸. 继续用酸降解法降解聚甘露糖醛酸,经凝胶柱层析分离纯化,获得系列甘露糖醛酸寡糖. 用荧光标记糖电泳(FACE)对寡糖进行了分析,并用电喷雾离子化质谱(ESI-MS)、 核磁共振波谱(NMR)及红外光谱(FTIR)进行了结构表征.
本研究用酸降解法制备饱和甘露糖醛酸寡糖,用凝胶柱层析法分离获得系列聚合度的寡糖,为褐藻胶大分子构效关系研究和药物的筛选与发现提供了重要的基础资料. 相似文献
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先采用均匀沉淀法制备出CuO—ZnO催化剂,然后以CuO—ZnO催化剂作为晶核采用水热合成法制备出CuO—ZnO/HZSM-5(氢型ZSM-5分子筛)复合催化剂.利用X射线衍射和氨程序升温脱附手段对复合催化剂进行表征,并应用于CO2催化加氢合成二甲醚的反应.研究结果表明,在相同的反应条件下,这种CuO—ZnO/HZSM-5复合催化剂与采用物理混合法制备出的复合催化剂相比具有更好的催化效果,不但提高了CO2的转化率、二甲醚的选择性以及二甲醚和甲醇的总选择性,同时还改善了催化剂的稳定性. 相似文献
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分子三维投影法在苯酚类化合物构效关系研究中的应用 总被引:4,自引:0,他引:4
对苯酚类化合物进行三维投影得到了5个形状参数,将其与3个Am指数及8个量子化学参数相结合.由最佳变量子集回归法对变量进行了压缩与选择,运用多元回归分析和人工神经网络法分别构造了预测数学模型,得到了满意的结果. 相似文献
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以有机溶剂热生长技术(solvothermaltechnique)制备了半导体硫族化合物(CdS、ZnS、MoS2)等纳米颗粒,采用XRD、TEM等技术对其结构进行表征.以ITO导电玻璃以及导电聚合物(PANI、PPY)膜为基底,将纳米颗粒涂布其上并以PL法研究其光学特性,实验结果表明:经修饰后,材料的荧光发射位置发生显著的变化. 相似文献
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Na-type faujasite was modified by SiCl4 treatment under dealumination-silicon-exchange reaction. Their crystallinities and lattice constants were analyzed by x-ray diffraction, and their surface areas and pore structures were measured by nitrogen adsorption at 77 K. Their hydrophobic characteristics were evaluated by measurements of water adsorption and heats of immersion into weter, and compared with those of ZSM-5 zeolites which were highly silicious at the synthesis process.Adsorption amount ofn-hexane on modified faujasite did not change compared to that on original faujasite, however, the adsorbed amount of water greatly decreased. Heats of immersion in water decreased by the modification and were closely related with the Si/Al ratio of zeolites. Hydrophilic-hydrophobic character is discussed from the viewpoint of water contact angle. 相似文献
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Six metal oxide samples were prepared by calcination of the corresponding precursors at 500°C for 5 h in air and were characterized
by IR and XRD analyses. Their surface areas were calculated by means of the BET method. The acidities and basicities of these
metal oxides were estimated thermogravimetrically by the method of adsorption of pyridine and formic acid as probe molecules.
The pyrolyses of pure ammonium perchlorate (AP) and of AP mixed with (10% w/w) metal oxide were studied, in a dynamic atmosphere
of N2, by thermogravimetric analysis (TG) and derivative thermogravimetric analysis. A correlation was found between the catalytic
activities of the metal oxides during the pyrolysis of AP, and their acidic-basic characters. The activation energies of the
non-catalyzed and catalyzed pyrolysis of AP were calculated from the TG results via the Coats-Redfern equation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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从超市选购15种微波适用塑料食品保鲜膜或袋作为样品,应用EN 1186-13-2002和GB/T 5009.156-2003两种标准方法中所述方法对样品在存放脂肪类食品时其组分迁移至食品中的总量做了测定。试验中用橄榄油和正己烷作为模拟食品,GB/T标准方法的检测结果表明:15种样品均属合格产品,而EN标准方法的检测结果表明在此15种样品中有4种属不合格,其合格率为73.3%。为探究两种方法所得结果存在差异的原因,采用红外光谱法(IR)、差示扫描量热法(DSC)及热失重法(TG)3种测试方法对上述样品作进一步研究。结果发现不合格的样品中含填料较高。此外,EN标准方法中所采用的样品预处理条件与实际使用情况更为接近。 相似文献
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气相色谱-质谱法测定阿尔泰狗娃花挥发精油中化学成分 总被引:1,自引:0,他引:1
采用水蒸气回流法提取阿尔泰狗娃花挥中挥发精油,用气相色谱-质谱法分离和鉴定阿尔泰狗娃花挥发精油中化学成分,用归一法测定其相对含量,共分离出50种化学成分,鉴定了39种化学成分,约占总成分相对含量的84.7%。 相似文献
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In order to investigate the long-term effect of the Százhalombatta power plant on the environment of the Csepel-Island subsoil samples were collected in 55 points within 200 km2. Using a microwave-assisted extraction procedure, Be, Ni and V were extracted from the soil samples by aqua regia and the metal concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS). The analytical results were evaluated by chemometric methods and interpreted considering the main mineral constituents of the subsoil. 相似文献