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1.
We describe identification of seven components from Antrodia cinnamomea. Their structures were determined on the basis of spectral analysis and comparison with authentic samples. These compounds include two steroids (1, 2) (β-sitosterol and eburicol), two new steroids (3, 4) [methyl-4α-methylergost-8,24(28)-dien-3,7,11-trion-26-oate and methyl-4α-methylergost-8,24(28)-dien-3,11-dion-26-oate], two lignans (5, 6) [(+)-sesamin and 4-hydroxysesamin], and one long chain methyl ester (7) (methyl oleate). Among them, compounds 3 and 4 are first isolated from nature. 相似文献
2.
采用高效液相色谱法对我国东北地区茄科植物废弃物马铃薯、茄子、番茄和辣椒的叶片中茄尼醇进行了定性和定量分析。结果表明:马铃薯和茄子的叶片中茄尼醇质量分数较高,分别可达到0.331%和0.207%;番茄和辣椒的叶片中茄尼醇的质量分数分别为0.092%和0.089%。方法的线性范围为0.61~6.10μg,回收率为99.5%~103.3%。 相似文献
3.
《Arabian Journal of Chemistry》2022,15(12):104308
This work aimed to identify the bioactive constituents of Ducrosia anethifolia Boiss eaves through cold methanolic extract. The GC–MS study of cold methanolic extract showed the presence of various pharmaceutically important bioactive compounds with unique peaks at specified retention time. The significant compounds are α-linoleic acid, α-sitosterol, n-hexadecanoic acid, palmitic acid β-monoglyceride, 2-methoxy-4-vinylphenol and benzoic acid, methyl ester. The FT-IR study showed them fingerprint region at 3326.80, 2943.53, 2831.74, 1450, 1110.67 and 1020.80 cm?1. The FT-IR study suggested the presence of glycosides, flavonoids, tannins, steroids, saponins, fatty acids and squalene. Oral administration of Ducrosia anethifolia Boiss leaves powder (DLP) (100 mg/kg body weight) was successfully reduced the blood sugar level after 14 d treatment in STZ (50 mg/kg bodyweight) induced diabetic rats significantly from 327.93 ± 24.5 to 171 0.03 ± 3.78 mg/dL. Furthermore, DLP (400 mg/kg body weight) was showed 74 ± 1.9 % inhibition of ulcer. The results of this study showed that DLP has both anti-diabetic and anti-ulcer characteristics when tested in vivo. 相似文献
4.
The value of intrinsic chlorophyll fluorescence polarization, and the intensity in emission spectrum were investigated in
leaf segments of Alocasia macrorrhiza under several stress conditions including different temperatures (25–50°C), various concentrations of NaCl (0–250 mM), methyl
viologen (MV, 0–25 μM), SDS (0–1.0%) and NaHSO3 (0–80 μM). Fluorescence emission spectrum of leaves at wavelength regions of 500–800 nm was monitored by excitation at 436 nm.
The value of fluorescence polarization (P value), as result of energy transfer and mutual orientation between chlorophyll molecules, was determined by excitation at
436 nm and emission at 685 nm. The results showed that elevated temperature and concentrations of salt (NaCl), photooxidant
(MV), surfactant (SDS) and simulated SO2 (NaHSO3) treatments all induced a reduction of fluorescence polarization to various degrees. However, alteration of the fluorescence
spectrum and emission intensity of F685 and F731 depended on the individual treatment. Increase in temperature and concentration of NaHSO3 enhanced fluorescence intensity mainly at F685, while an increase in MV concentration led to a decrease at both F685 and F731. On the contrary, NaCl and SDS did not cause remarkable change in fluorescence spectrum. Among different treatments, the
negative correlation between polarization and fluorescence intensity was found with NaHSO3 treatments only. We concluded that P value being measured with intrinsic chlorophyll fluorescence as probe in leaves is a susceptible indicator responding to
changes in environmental conditions. The alteration of P value and fluorescence intensity might not always be shown a functional relation pattern. The possible reasons of differed
response to various treatments were discussed. 相似文献
5.
Differentiating parts of Cinnamomum cassia using LC‐qTOF‐MS in conjunction with principal component analysis 下载免费PDF全文
Pei‐Yi Chen Jhe‐Wei Yu Fen‐Ling Lu Mei‐Chih Lin Hwei‐Fang Cheng 《Biomedical chromatography : BMC》2016,30(9):1449-1457
Cinnamon bark (Rou Gui in Chinese), cinnamon twig (Gui Zhi) and shaved cinnamon bark (Gui Sin) have been widely used as spices and in traditional Chinese medicine since ancient times. On‐going issues related to quality and authenticity necessitate the development of analytical methods capable of providing an objective evaluation of samples. In this study, chemical fingerprints of cinnamon bark, cinnamon twigs and shaved cinnamon bark were established using liquid chromatography quadruple time‐of‐flight mass spectrometry in conjunction with principal component analysis (PCA). From 125 samples of cinnamon, we identified the following eight compounds and their the detection ratios: coumarin, cinnamaldehyde, cinnamyl alcohol, cinnamic acid, 2‐hydroxycinnamaldehyde, 2‐hydroxycinnamic acid, 2‐methoxycinnamaldehyde and 4‐methoxycinnamaldehyde. Of these, 4‐methoxycinnamaldehyde presented the largest variations in detection ratio, making up 64.0, 97.4 and 50.0% in cinnamon bark, cinnamon twig, and shaved cinnamon bark, respectively. The quantities of cinnamyl alcohol, coumarin and cinnamaldehyde also varied between the three parts of the plant. Chemical fingerprints of the three cinnamon samples were established using principal component analysis, the results of which indicate that cinnamon bark and shaved cinnamon bark could be easily differentiated, despite a marked similarity in outward appearance. Cinnamon twig was also shown to depart from the other clusters. The proposed method provides a fast and efficient means of identifying cinnamon herbs for quality control purposes. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
6.
Smithia conferta Sm. (Leguminasae), is a commonly used plant in Indian traditional medicine. In the current study anti-ulcer activity of its petroleum ether, alcohol and aqueous extracts of leaves were investigated using different animal models. All extracts were also subjected to phytochemical analysis and their toxic potential. Petroleum ether extract was found to contain steroids; alcohol extract revealed the presence of isoflavonoids, alkaloids and carbohydrates; while aqueous extract was found to contain amino acids, carbohydrates and flavonoids. S. conferta aqueous and alcoholic extracts were found to be non-toxic up to 5000 mg/kg dose level while petroleum ether extract was safe only up to a dose of 2000 mg/kg after single dose administration of the extracts.During confirmation of the claimed anti-ulcer activity, treatment with aqueous and alcoholic extracts showed significant reduction in ulcer index, free acidity as well as total acidity in pylorus ligated rats. However, petroleum ether extract showed relatively less profound reduction in all these indices. The anti-ulcer activity observed in aqueous extract treatment group was nearly equivalent to the standard group. 相似文献
7.
J. Sanz-Landaluze M. Bocanegra-Salazar D. Ortiz-Pérez C. Cámara 《Journal of chromatography. A》2010,1217(22):3567-3574
A new methodology is proposed for monitoring 16 priority polycyclic aromatic hydrocarbons, using tree leaves as passive samplers, by means of a mini-ultrasonic probe coupled with reversed-phase liquid chromatography (RP-LC) and fluorescence (FL) detection. Separation and detection of the 16 PAHs were completed in 19 min, using a 3 μm (particle size) C18 column RP-LC with acetonitrile–water gradient elution. The ultrasonic probe device used was equipped with a 2 mm titanium tip, and sample and solvent amounts used were just 50 mg and 1 mL, respectively. Multivariate optimisation of the variables affecting extraction was conducted by means of full factorial analysis to determine which of the variables were significant. A central composite design was applied to define surface responses and to calculate optimal values for the variables. The accuracy of the method was determined by both analysis of a Certified Reference Material with a similar matrix (IAEA-140 OC, seaweed) and by comparison of the results obtained with those from a previously developed method. The proposed analytical method avoids some of the main problems encountered in the determination of PAH in complex matrices; no clean-up step is necessary, consequently sample preparation time and costs can be significantly reduced. The developed method was applied to determine PAH in leaf samples from medlar and red and white mangrove trees, situated near PAH pollution sources. 相似文献
8.
9.
Various topological indices have been put forward in different studies, from biochemistry to pure mathematics. Among them, the Wiener index, the number of subtrees, and the Randi? index have received great attention from mathematicians. In the study of extremal problems regarding these indices among trees, one interesting phenomenon is that they share the same extremal tree structures. Much effort was devoted to the study of the correlations between these various indices. In this note we provide a common characteristic (the ‘semi-regular’ property) of these extremal structures, with respect to the above mentioned indices, among trees with a given maximum degree. This observation leads to a more unified approach for characterizing these extremal structures. As an application/example, we illustrate the idea by studying the extremal trees, regarding the sum of distances between all pairs of leaves of a tree, a new index, which recently appeared in phylogenetic tree reconstruction, and the study of the neighborhood of trees. 相似文献
10.
Precipitate-type electrodes (benzidine sulfate or phosphate and hexammino-cobalt(III) nitrate in silicone rubber), and liquid ion-exchanger electrodes based on quaternary ammonium and phosphonium and triphenyltin salts were tested for the assay of phosphate ions. Good sensitivity was achieved with the phosphonium and triphenyltin salts, but both lacked sufficient selectivity for routine-assays. 相似文献