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Xiang Cui Yu‐meng Shen Shu Jiang Da‐wei Qian Er‐xin Shang Zhen‐hua Zhu Jin‐ao Duan 《Journal of separation science》2019,42(8):1520-1527
In this study, a rapid and highly sensitive ultra high performance liquid chromatography with triple quadrupole mass spectrometry method with the mobile phase of acetonitrile and 0.1% aqueous formic acid was established and successfully applied to comparatively analyze main active components after their compatibility. Besides, the effects of Scutellariae Radix, Coptidis Rhizoma and combined extracts on type 2 diabetic rats induced by high‐fat diet along with low dose of streptozocin were investigated. Under the optimized chromatographic conditions, good separation of seven target components was achieved within 12 min. All calibration curves exhibited good linearity (R2 ≥ 0.999). The relative standard deviation of precision, repeatability and stability varied from 0.69 to 2.23, 0.98 to 2.56, and 0.92 to 2.57%, respectively. The recovery ranged from 91.11 to 105.35%. The contents of seven active components were notably reduced after compatibility; however, the hypoglycemic effect of combined extracts was stronger than single drug by decreasing the activities of fructose‐1,6‐bisphosphatase, glucose 6‐phosphatase, phosphoenolpyruvate carboxykinase and increasing the activities of glucokinase, phosphofructokinase, pyruvate kinase. Accordingly, the established analytical method was accurate and sensitive enough for quantitative evaluation of seven investigated compounds. Moreover, the combined extract had definite effects on type 2 diabetes through multiple components against multiple targets. 相似文献
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张穗萌 《原子与分子物理学报》2003,20(2):247-251
在Chen等人工作(2001,Chin. Phys. 10 290)的基础上,进一步对(e,2e)反应的末态He+中核外电子的有效屏蔽给出修正.并用修正后的索末菲参量计算了入射能为40 eV时,共面不对称几何条件下电子离化He原子的三重微分截面.所得结果与其它理论结果及最新绝对测量的实验数据进行比较发现:所得到的理论曲线更接近实验数据. 相似文献
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在强光一号脉冲加速器上进行了国内首次的实验室软X光辐射三种材料的喷射冲量研究。结果表明,在能量为(0.2~0.33)keV、平均脉宽为39ns左右的X光辐射下,对灰漆、白漆和硬铝,在能注量分别为(92~152)J/cm2、(115~136)J/cm2和(163~192)J/cm2时,它们的冲量耦合系数分别为(0.61~0.80)Pa·s/(J·cm-2)、(0.58~0.97)Pa·s/(J·cm-2)和(0.61~0.84)Pa·s/(J·cm-2)。 相似文献
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使用振声法探测埋地物体时,表层土壤松软导致地表振动传感器在耦合环节发生谐振, 造成谐频附近的信号失真,限制了所采信号的可用频段。针对传感器在水平方向的耦合谐振问题,该文研究了传感器质量对谐振频率的影响。仿真对比了传感器质量为2~250 g情况下信号采集系统的频响特征,并在季节性的冻土地表开展了对比实验与横波波速测量实验。仿真与实验结果表明:250 g传感器所对应的耦合谐频不超过800 Hz;2 g传感器的耦合谐频可超过1200 Hz;传感器质量越轻,耦合谐振频率越高,所采信号的可用频段越宽。 相似文献
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王大猛 《新疆大学学报(理工版)》2001,18(2):129-135
发展了Ky Fan中定理4的结果,对复的Hilbert空间H上的真压缩算子A和单位圆盘△内的解析函数f给出了优势原理,与文比较,本文去掉A为正规算子的限制,并改进了相应的结果,对H(△)的某个子类中的f,给出‖f′(A)‖的估值,并讨论了从属关系的优势原理,特别是把Shah-Goluzin关于从属于单叶函数的优势半径拓广到算子函数。 相似文献
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肿瘤体内诊断和治疗中 ,不管是采用氯胺———T lodogen[1] 的直接标记法 ,还是Bolton Hunter[2 ] 试剂的间接标记法制备的放射性碘化蛋白质、存在一个主要问题 ,是它们在体内较快脱碘并使放射性碘被甲状腺所摄取。脱碘的产生被认为是这些碘酚基与甲状腺素存在类似结构以及放射性碘在芳环的取代位置。Zalutsky的研究指出 :用三正丁基锡苯甲酸 N 丁二酰亚胺酯为碘化试剂[3 ,4 ] 可解决此类问题 ,但该试剂合成相当复杂 ,因而探索合成类似化合物的简单途径很有意义。选用烟酸为原料合成的偶联剂氯化汞代烟酸 N … 相似文献