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31.
建立了高效液相色谱分离测定粘毛鼠尾草中一种新吉玛烷型倍半萜,3β,6β,8α-三乙酰氧基-4β,5α-环氧吉玛-1-烯的方法:采用Kromasil C18反相色谱柱,以甲醇-水(体积比75:25)为流动相,流速0.8mL/min,检测波长204nm,在10min内分离检测该倍半萜。结果 线性范围0.065~32.5μg,相关系数0.999,检出限0.01μg,平均回收率98%,RSD3.1%。测得粘毛鼠尾草全草石油醚提取物中该吉玛烷倍半萜的含量为20.9mg/g。  相似文献   
32.
Study on dye-sensitized solar cells (DSSCs) with extracts of Canna indica L., Salvia splendens, Solanum nigrum L. as sensitizers is firstly reported in this paper. DSSCs were assembled by using natural dyes extracted from C. indica L., S. splendens, cowberry and S. nigrum L. as sensitizers. The energy conversion efficiency of the cells sensitized with dyes of C. indica L., S. splendens, cowberry and S. nigrum L. was 0.29%, 0.26%, 0.13% and 0.31%, respectively. A novel technique was taken to fabricate TiO2 electrode films by electrophoresis. We present FTIR and UV–vis spectroscopy studies of structures and light absorption of these four kinds of natural dyes. The electrochemical impedance spectroscopy (EIS) was used to analyze the interface resistance of cells. The result indicated that high resistance existed in the interfaces of cell with cowberry extract as sensitizer.  相似文献   
33.
Salvia miltiorrhiza, also known as Danshen, is a widely used traditional Chinese medicine for the treatment of cardiovascular diseases and hematological abnormalities. The root and rhizome of Salvia przewalskii and Salvia yunnanensis have been found as substitutes for Salvia miltiorrhiza in the market. In this study, the chemical information of 14 major compounds in Salvia miltiorrhiza and its substitutes were determined using a high‐performance liquid chromatography method. Stepwise discriminant analysis was adopted to select the characteristic variables. Partial least squares discriminant and hierarchical cluster analysis were performed to classify Salvia miltiorrhiza and its substitutes. The results showed that all of the samples were correctly classified both in partial least squares discriminant analysis and hierarchical cluster analysis based on the four compounds (caffeic acid, rosmarinic acid, salvianolic acid B, and salvianolic acid A). This method can not only distinguish Salvia miltiorrhiza and its substitutes, but also classify Salvia przewalskii and Salvia yunnanensis. The method can be applied for the quality assessment of Salvia miltiorrhiza and identification of unknown samples.  相似文献   
34.
首次采用红外光谱三级鉴定法对丹参不同部位的药材粉末及其水提物和醇提物进行了分析与评价研究。结果表明, 一维图谱中, 丹参花与根的相似系数最高, 为0.9123 ; 叶在1650~1611 cm- 1的特征峰峰高明显高于其他部位; 二阶导数谱中, 1160~1000 cm-1范围内吸收峰的峰形、相对峰强有所差异, 不同部位水提物和醇提物的分析结果进一步明确了丹参根、茎、叶、花存在差异; 二维相关光谱中, 茎与叶、根与花的二维相关谱图仍较为相似, 印证一维及二阶导数谱结论。  相似文献   
35.
近年来对中药材中微量元素的研究,以及微量元素在药效中的作用和对人体健康的影响越来越引起人们的重视。文章借助ICP-MS/ICP-AES技术分析比较了4个产地丹参种质同地种植根中微量元素的含量。结果发现,实验的4个丹参种质中,以山东白花丹参根中微量元素含量较高,钙、铁、锌、锰、铜、钡、锂、钴、镍、汞等10种微量元素含量是最高的,且锌、锰、铜、镍、汞等微量元素含量显著高于其他3种紫花丹参;相比紫花丹参和白花丹参根中微量元素含量的差异,3种紫花丹参之间,除了陕西商洛紫花丹参根中铷和钼的含量较低、镍的含量较高外,其他19种微量元素含量都较为接近。4个产地种质丹参根中微量元素含量的测定,为了解各自根中药效成分的含量及其疗效差异提供了重要参考。  相似文献   
36.
用微波消解-火焰原子吸收光谱法测定了康定鼠尾草药材中8种元素(钙、铜、铁、锰、锌、镁、铅、镉)的含量。结果表明,康定鼠尾草药材中含有较丰富的镁、钙、铁,该法灵敏度高、快速、准确,所测数据可为康定鼠尾草药材的合理利用提供可靠依据。  相似文献   
37.
Two new eudesmanolide sesquiterpenoids containing a hemiacetal function, castanins G and H ( 1 and 2 ), were obtained as a pair of interconvertible isomers from the aerial parts of Salvia castanea Diels f. tomentosa Stib. , and separated as their uninterconvertible acetates 3 and 4 . Their structures were elucidated by unequivocal interpretation and comparative analysis of the NMR and MS data of the mixture 1 / 2 and of their acetates 3 and 4 , respectively. The inhibitory activity of 3 and 4 toward MCF‐7, HeLa, and HepG2 cell lines was also evaluated.  相似文献   
38.
Public use of Salvia species and their importance in the scientific world is continually increasing. It is known that this use and the importance of Salvia species are mostly due to the terpenoid compounds that they contain. In this context, the terpenoid–steroid–flavonoid contents of extracts of six endemic Salvia (S. kurdica, S. pseudeuphratica, S. rosifolia, S. siirtica, S. cerino-pruinosa var. cerino-pruinosa and S. cerino-pruinosa var. elazigensis) species prepared with different solvents were determined by gas chromatography–mass spectrometry. Within the framework of the ingredient analysis, content analysis of the ethanol extracts of the root, branch, leaf and flower parts of the species collected in the same period between 2015 and 2017 years was performed. In general, extracts prepared with chloroform and ethanol were found to contain a wide variety of compounds while petroleum ether extracts were found to contain much less varied compounds. In addition, in general, root extracts are richer in terpenoid compounds than aerial part extracts. Some species can be used as source species in terms of ferruginol, cryptanol, 6,7-dehydroroyleanone, lup-(20)29-ene-2α-hydroxy-3β-acetate, salvigenin and β-sitosterol contents (52,114.28, 75,979.08, 101,247.41, 40,071.29, 33,952.13 and 34,010.90 μg analyte/g extract, respectively).  相似文献   
39.
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   
40.
Nine compounds were successfully separated from Salvia plebeia R.Br. using two‐step high‐speed counter‐current chromatography with three elution modes. Elution–extrusion counter‐current chromatography was applied in the first step, while classical counter‐current chromatography and recycling counter‐current chromatography were used in the second step. Three solvent systems, n‐hexane/ethyl acetate/ethanol/water (4:6.5:3:7, v/v), methyl tert‐butyl ether/ethyl acetate/n‐butanol/methanol/water (6:4:1:2:8, v/v) and n‐hexane/ethyl acetate/methanol/water (5:5.5:5:5, v/v) were screened and optimized for the two‐step separation. The separation yielded nine compounds, including caffeic acid ( 1 ), 6‐hydroxyluteuolin‐7‐glucoside ( 2 ), 5,7,3′,4′‐tetrahydroxy‐6‐methoxyflavanone‐7‐glucoside ( 3 ), nepitrin ( 4 ), rosmarinic acid ( 5 ), homoplantaginin ( 6 ), nepetin ( 7 ), hispidulin ( 8 ), and 5,6,7,4′‐tertrahydroxyflavone ( 9 ). To the best of our knowledge, 5,7,3′,4′‐tetrahydroxy‐6‐methoxyflavanone‐7‐glucoside and 5,6,7,4′‐tertrahydroxyflavone have been separated from Salvia plebeia R.Br. for the first time. The purities and structures of these compounds were identified by high‐performance liquid chromatography, electrospray ionization mass spectrometry, 1H and 13C NMR spectroscopy. This study demonstrates that high‐speed counter‐current chromatography is a useful and flexible tool for the separation of components from a complex sample.  相似文献   
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