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排序方式: 共有462条查询结果,搜索用时 15 毫秒
111.
Xin Cun TANG Tian Duo LI College of Chemistry Chemical Engineering Central South University Changsha Shandong Institute of Light Industry Jinan 《中国化学快报》2005,16(8):1077-1080
Investigation on the solid diffusion process of intercalary species within insertion-host materials plays an important role in the energy storage and output of secondary batteries1. To determine the solid diffusion coefficient, several electrochemical techniques have been developed such as galvanostatic intermittent titration (GITT)2,3, electrochemical impedance spectroscopy (EIS)4,5, potential intermittent titration technique (PITT)6, and potential step chronoamperometry (PSCA)7, potenti… 相似文献
112.
低酸度淋洗液离子色谱法测定多聚磷酸盐 总被引:1,自引:0,他引:1
在国产阴离子分离柱上采用含钙和镁离子的淋洗液,由于Ca^2+和Mg^2+与复杂的多聚磷酸根离子形成螯合物而提高了淋洗能力,加快了分析速度,大大降低了淋洗液的酸度和盐浓度,对几种工业三聚磷酸钠样品进行了测定,与化学法相比,相对误差小于1.5%,加入回收率在99%-109%之间。 相似文献
113.
In this work, the values of the heterogeneous standard rate constant and the transfer coefficient of the electrochemical system Fe(III)/Fe(II) in 1 M H2SO4 at a polycrystalline gold electrode were determined. The response spectrum to an ac potential of such amplitude as to make the behaviour of the electrode process non-linear was analysed. The experimental study was complemented by a theoretical study of the Fe(III)/Fe(II) system using numerical methods. Comparison of the experimental and theoretical data enabled the kinetic parameters of this electrode process to be determined. 相似文献
114.
长管香茶菜B(LongikaurinB)分子的化学计量式为C22H30O7,Mr=406.47,用X射线衍射法确定其晶体结构,该结晶是无色透明柱状,属单斜晶系,空间和群为P21,晶胞参数:a=11.893(2),b=6.380(2),c=13.205(2)A,β=99.39(2)°,Z=2,V=988.5(4)A3,Dc=1.366g/cm3,F(000)=436,u=0.9cm-1。应用直接法解析分子结构,以最小二乘法修正结构参数。最终可靠因子R=0.042,Ra=0.043。结果表明,该化合物为长管香茶菜B,属7,20-氧桥-对映-贝壳杉烯型工花化合物。结构与功能关系研究表明LongikaurinB化合物可能具有抗肿瘤生物活性。 相似文献
115.
Margaret Phiri Duo Li Tengfei Li Shunli Ji Tang Ling Xianjing Li Huaye Gao Li Ding Chang Shu 《Biomedical chromatography : BMC》2020,34(10):e4904
A simple LC–tandem mass spectrometry (MS/MS) method to determine ebastine and carebastine (active metabolite) in human plasma was developed and validated. Analytes and internal standards were precipitated by protein precipitation and separated on Synergi Hydro-RP 80A column (4 μm, 50 mm × 2.0 mm; Phenomenex) by gradient elution with mobile phase A comprising 0.1% formic acid in 5 mm ammonium acetate (NH4Ac) and B comprising 100% methanol at a flow rate 0.4 mL/min. Ions were detected in positive multiple reaction monitoring mode, and they exhibited linearity over concentration range 0.01–8.0 and 1.00–300 ng/mL for ebastine and carebastine, respectively. A clinical pharmacokinetic study was conducted in healthy Chinese volunteers under fasting and fed conditions after a single oral administration of 10 mg ebastine. The maximum plasma concentration (Cmax), time to Cmax (Tmax) and elimination half-life for ebastine were 0.679 ± 0.762 ng/mL, 1.67 ± 1.43 h and 7.86 ± 6.18 h, respectively, whereas these for carebastine were 143 ± 68.4 ng/mL, 5.00 ± 2.00 h and 17.4 ± 4.97 h, respectively under fasting conditions; the corresponding values under fed conditions were 4.13 ± 2.53 ng/mL, 3.18 ± 1.09 h and 21.6 ± 7.77 h for ebastine and 176 ± 68.4 ng/mL, 6.14 ± 2.0 h and 20.0 ± 4.97 h for carebastine. 相似文献
116.
Mathematische Zeitschrift - A simple birational map is a K-equivalent birational map which is resolved by a single blowing-up. Examples of such maps include standard flops and twisted Mukai flops.... 相似文献
117.
Nasopharyngeal carcinoma is one of the most common malignant neoplasms in head and neck. In this work, surface-enhanced Raman spectroscopy technique was used to study the molecular differences between cancerous and noncancerous smear samples which were obtained after clinical biopsy by smearing the tissue on the slides. Principal component analysis combined with linear discriminant analysis provided a sensitivity of 79.4% and a specificity of 81.8% for differentiation between cancerous and noncancerous nasopharyngeal tissue smears. This work provides a good basis for the methodology of nasopharyngeal tissue smear based on surface-enhanced Raman spectroscopy technique and is worth further studying. 相似文献
118.
Yong‐Miao Shen Yi‐Jun Du Min‐Feng Zeng Duo Zhi Sheng‐Xian Zhao Lin‐Mei Rong Shao‐Qin Lv Lin Du Chen‐Ze Qi 《应用有机金属化学》2010,24(9):631-635
A novel palladium catalyst supported on shell powder has been prepared, and its application to the Heck reaction of aryl iodides with olefins has been reported. The results showed that the novel catalyst had extremely high activities for the reactions with the average yield over 90%. Also, this catalyst showed excellent stability in Heck reactions, being reused three times. The catalyst was characterized by X‐ray powder diffraction and field‐emission scanned electron microscopy images, and the energy dispersive X‐ray analyzer. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
119.
Xin‐Yi Huang Qiu‐Yan Duan Jun‐Xi Liu Duo‐Long Di 《Biomedical chromatography : BMC》2010,24(3):307-311
A simple and reliable analytical method based on high‐performance liquid chromatography (HPLC) coupled with a diode array detector (DAD) was developed for the determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma using rhoiptelol as an internal standard. Chromatographic separation was carried out on a Sinochrom ODS‐AP C18 column (250 × 4.6 μm i.d., 5 mm) with acetonitrile–10 mM postassium dihydrogen phosphate (pH = 3; 55:45, v/v) as mobile phase, and the detection wavelength was set at 214 nm. The plasma samples were prepared using methanol as protein precipitator. The extraction recovery of Juglanin B ranged from 70.26 to 78.59%, and the calibration curve had a good linearity in the range 0.08–50 μg/mL (r2 = 0.9932). The RSDs of intra‐ and inter‐day precision ranged from 1.19 to 4.92% and 4.35 to 4.54%, respectively. The HPLC‐DAD method described is a simple, rapid and reliable method for the determination of Juglanin B level and for use in studies involving pharmacokinetics. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
120.