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11.
A large-scale purification of salvianolic acid B from Salvia miltiorrhiza Bunge is presented. The method development began with selection of the solvent system, then optimization of the operating parameters and ended up with linear scale-up from an analytical to a preparative instrument. Three factors were used for method optimization and scale-up estimation: purity, process throughput and process efficiency. Preparation was achieved using a two-phase solvent system comprising hexane–ethyl acetate–methanol–acetic acid–water (1:5:1.5:0.00596:5, v/v). This preparation yielded 475 mg of salvianolic acid B with a purity of 96.1% from 1.5 g of crude extract. The process throughput of crude was 2.23 g/h while process efficiency per gram of target compound was 0.769 g/h. Two factors—process environmental risk factor and process evaluation factor were used for evaluation of the separation process.  相似文献   
12.
结合椒目化学成分的分离提取方法,采用AFS-3100原子荧光光谱法,分析了不同产地椒目中的砷含量及其形态。使用0.45 μm滤膜和混合溶剂提取的方法将椒目中的砷分为悬浮态和可溶态,并使用离子交换树脂将可溶态中的砷分为As(Ⅲ),As(Ⅴ),MMA,DMA,建立了砷的四种形态分离分析方法。结果显示,各产地椒目中均以无机砷为主且As(Ⅴ), 含量较As(Ⅲ)高,甲醇-水(4∶1)对椒目中砷的浸提率高,椒目水可煎出态总砷百分率为53.7%~62.3%。应用本方法对椒目中的砷进行形态分析,回收率在96.0%~101.3%范围内,RSD小于2.66%。表明其灵敏度高,重现性好。  相似文献   
13.
反相-高效液相色谱分析茶条槭叶中多酚类化合物   总被引:1,自引:0,他引:1  
本文建立了反相高效液相色谱法( RP-H PLC)测定茶条槭叶中多酚类化合物含量的方法.采用XTerra-C18色谱柱,选择流动相为甲醇-乙酸-水,检测波长分别为278nm(0~30 min)和360 nm(30~35 min),流速0.5 mL/min的色谱条件,对茶条槭叶进行定性、定量分析.结果表明,此方法精密度高...  相似文献   
14.
pH-Zone-refining countercurrent chromatography was successfully applied to the separation of salvianolic acid B from the Chinese medicinal plant, Salvia miltiorrhiza Bunge, using a multilayer coil planet centrifuge. A 2.0 g quantity of sample was separated using the following two-phase solvent system: methyl tert-butyl ether (MtBE)-water, 10 mM TFA in organic stationary phase and 10 mM ammonia in aqueous mobile phase. The obtained fractions were analyzed by HPLC and ESI-MS. The separation yielded 572 mg of the main component of salvianolic acid B with a purity of 94.1%.  相似文献   
15.
作为浙江槭属植物区系的补充,报道了浙闽槭Acer johnedwardianum F.P.Metcalf、乳源槭A. chunii Fang和九江三角枫A. buergerianum Miq. var. jiujiangense Z.X. Yu 3个植物分布新记录;补充描述了浙闽槭、乳源槭花的形态特征;恢复了浙闽槭的种级地位。  相似文献   
16.
Two new saponins were isolated from husks of Xanthoceras sorbifolia Bunge and their structures were elucidated as 3‐O‐[β‐D‐galactopyranosyl(1→2)]‐α‐L‐arabinofuranosyl(1→3)‐β‐D‐methyl glucuronic acid‐21‐O‐(3,4‐diangeloyl)‐α‐L‐rhamnose‐3β, 16α, 21β, 22α, 28β‐pentahydroxyl‐22‐acetoxy‐olean‐12‐ene(1) and 3‐O‐[β‐D‐galactopyranosyl(1→2)]‐α‐L‐arabinofuranosyl(1→3)‐β‐D‐methyl glucuronic acid‐21,22‐O‐diangeloyl‐3β,15α,16α,21β,22α,28β‐hexahydroxyl‐olean‐12‐ene(2) on the basis of 1D and 2D NMR (including 1H, 13C‐NMR, 1H? 1H COSY, HSQC, HMBC and DEPT), ESI‐MS spectrometry and chemical methods. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
17.
原子吸收法测定椒目中不同化学形态的锌含量   总被引:1,自引:1,他引:0  
结合椒目的市场前景与药效,采用原子吸收分光光度法,分析了不同产地椒目中的锌含量及其形态。使用0.45 μm滤膜、CHCL3将椒目水煎液中的锌分为悬浮态和可溶态、有机态和无机态,建立了锌的四种形态分离分析方法;探讨了正辛醇-水分配体系模拟水煎液中锌在人体胃肠中的分配情况;并采用原子吸收分光光度法测定了椒目中的锌在不同溶剂中的化学形态和溶出特性。结果表明,椒目中的锌以水可煎出态为主,不同产地椒目锌含量不同,但水可煎出态总锌百分率、有机态总锌百分率基本接近。该方法回收率在97.5%~104.0%范围内,相对标准偏差均小于2.36%。应用于实际,结果表明其灵敏度高,重现性好。  相似文献   
18.
浙江槭属植物新记录   总被引:1,自引:0,他引:1  
作为浙江槭属植物区系的补充,报道了浙闽槭Acer johnedwardianum F.P.Metcalf、乳源槭A. chunii Fang和九江三角枫A. buergerianum Miq. var. jiujiangense Z.X. Yu 3个植物分布新记录;补充描述了浙闽槭、乳源槭花的形态特征;恢复了浙闽槭的种级地位。  相似文献   
19.
Sedum sarmentosum Bunge (SSB) is a traditional Chinese herbal medicine containing multiple components that has been extensively used clinically to treat chronic viral hepatitis and some inflammatory diseases. Total flavonoids are major pharmacologically active components of SSB. To gain a deeper understanding of SSB resources, we analyzed eight chemical constituents in 33 batches of SSB from 11 regions in China. An accurate, precise and sensitive ultra‐high‐performance liquid chromatography coupled with triple quadrupole electrospray tandem mass spectrometry method was developed for the determination of eight flavonoids in SSB. Under the optimized chromatographic conditions, good separation for the eight target components was obtained on an Agilent Zobax SB C18 (50 × 2.1 mm, 5 μm) column within 4 min. The established methods were validated with good linearity (r ≥ 0.9988), precision (RSD ≤ 2.68%), stability (1.43–3.28%) and repeatability (1.14–2.89%). Moreover, the average recoveries were 95.91–100.68%, and the RSDs were 1.50–3.80%. In addition, the analytical conditions of UPLC–ESI–MS/MS provided better sensitivity with a shorter analysis time when compared with the HPLC–DAD method. Hierarchical clustering analysis and principal component analysis were performed to estimate and classify these samples based on the contents of the eight chemical constituents. This study provided the theoretical basis and scientific evidence for the development and utilization of SSB resources.  相似文献   
20.
用GC/MS分析几种葱属植物挥发油中的有机硫化物   总被引:3,自引:0,他引:3  
采用蒸汽蒸馏的方法,分别提取了大葱(Allium fistulosum L)、薤白(Allium macrostemonBunge)和大蒜(Allium sativum L)中的挥发油,用GC/MS方法鉴别了它们中的主要硫化合物,并进行了比较。  相似文献   
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