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排序方式: 共有322条查询结果,搜索用时 46 毫秒
1.
以金银花为试材,研究了叶面喷施稀土镧对金银花中重金属及药效成分含量的影响。结果显示以过氧化物酶活性和叶绿素含量为指标,确定以30 mg·L-1的甘氨酸镧水溶液叶面喷施效果较好。30 mg·L-1的甘氨酸镧水溶液处理的金银花中,Cd,Cu和As含量与对照相比明显下降,同时药效成分绿原酸和木犀草苷的含量分别增加了9.14%和43.86%。与药典标准相比,重金属含量和药效成分含量都明显优于2010版药典标准。结果表明:适宜浓度稀土镧对金银花吸收重金属元素有抑制作用,并且能促进其药效成分的合成,进而提高金银花的品质。 相似文献
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The diffuse reflectance infrared spectra of TiO2 thin films deposited on different base materials and formed under different experimental conditions(temperature, ratio of tetrabutyl titanate to water and adulteration of different metallic elements) were determined and the structure of the films were discussed. 相似文献
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Shuqin Li Xingen Hu Ruisen Lin Wenqiang Sang Wenjun Fang 《Journal of solution chemistry》2001,30(4):365-373
Densities of solutions of glycine, L-alanine, and L-serine have been measured by an oscillating-tube densimeter at 25°C in glycerol–water mixtures with glycerol mass fractions ranging from 0 to 0.50. Apparent molar volumes and limiting partial molar volumes of each amino acid have been calculated. The trends of transfer volumes have been interpreted by the cosphere overlap model. The results show that the presence of glycerol in water decreases the electrostriction caused by the amino acid zwitterion. 相似文献
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Surface photovoltage spectroscopy equations for cathode materials with an AlxGa1-x As buffer layer are determined in order to effectively measure the body parameters for transmission-mode (t-mode) photocathode materials before Cs-O activation.Body parameters of cathode materials are well fitted through experiments and fitting calculations for the designed AlxGa1-x As/GaAs structure material.This investigation examines photo-excited performance and measurements of body parameters for t-mode cathode materials of different doping structures.It also helps study various doping structures and optimize structure designs in the future. 相似文献
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Takashi Yoshida Rong Lu Shuqin Han Kazuyuki Hattori Takahiro Katsuta Kei‐Ichi Takeda Kazutoshi Sugimoto Masamitsu Funaoka 《Journal of polymer science. Part A, Polymer chemistry》2009,47(3):824-832
For the synthesis of a new biologically functional polymer from a natural resource by an environment‐friendly method, the laccase‐catalyzed polymerization of a lignin‐based macromonomer, lignocatechol, was carried out for the first time in ethanol–phosphate buffer solvent system to give crosslinked polymers in good yields. Lignocatechol was prepared by the phase separation system of lignin and catechol in aqueous sulfuric acid. The copolymerization was also performed with urushiol to afford the corresponding copolymers in high yields. The polymerization mechanism was estimated by the IR and pyrolysis GC‐MS measurements, suggesting that the polymerization proceeded mainly at the catechol ring through a quinone radical intermediate. The thermal properties were measured by the DSC, TG, and TMA analyses, indicating that the polymers had high thermal stabilities because of the crosslinked structures. In addition, it was found that the resulting polymers had the affinity of bovine serum albumin (BSA) and glucoamylase. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 824–832, 2009 相似文献
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本文首先给出了Z4-线性码C4(m,D)的一个大的自同构子群.然后,利用该自同构子群得到了C4(m,6)当m为奇数时的Lee重量分布的一个约化公式.最后,利用该约化公式及计算机搜索得到C4(7,6)的Lee重量分布.C4(7,6)经Gray映射后得的二元非线性码与最优二元线性码[256,37,92]有相同的参数. 相似文献
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