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51.
Cellulose - In this study, microcrystalline cellulose (MCC) was modified to oxidized cellulose (OC), 6-deoxycellulose hydrazide and 6-deoxycellulose (N,N-diethyl)amine (MCC-Hyd and MCC-DEM)...  相似文献   
52.
Journal of Thermal Analysis and Calorimetry - In the present work, a series of experiments were designed and conducted to prepare biodiesel from cottonseed oil and to blend it with octanol. The...  相似文献   
53.
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, the affiliations of the third, fourth and fifth authors were incorrectly published.  相似文献   
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55.
In the present work, the exact solutions of Stokes second problem for a Burgers’ fluid are investigated. The expressions for the velocity field and the corresponding tangential stress are obtained when the relaxation times satisfy the condition γ < λ2/4. The solutions have been determined by means of Laplace transform. Only one initial condition is necessary for velocity and these solutions presented in the forms of simple or multiple integrals in terms of Bessel functions. The corresponding solutions for a Newtonian fluid as well as Oldroyd-B fluid appear as the limiting cases of the presented results. The obtained solutions are graphically analyzed for the variations of interesting flow parameters. Moreover, a comparison for velocity is made with Oldroyd-B and Newtonian fluids.  相似文献   
56.
The objective was to assess the effects of commercial regular diet as control, total food restriction with honey, commercial regular diet with dextrose, or total food restriction with dextrose, on blood variables after carbon tetrachloride (CCl4) administration. Sprague Dawley albino rats were divided into four groups, 10 rats each; Group 1 rats were on commercial regular diet, Group 2 rats were on commercial regular diet with 50% dextrose, Group 3 rats were on total food restriction with 50% dextrose, and Group 4 rats were on total food restriction with 50% honey. Rats in all the groups were i.m. administered CCL4 (2.4 mL kg b. wt.-1). Blood tests including ALT, AST, serum albumin, serum protein, BUN, blood glucose (BG), hemoglobin (Hb), and white blood cell (WBC) were performed before CCl4 administration and repeated after 48 and 96 h of post-injection. In Group 1, CCl4 caused significant elevation in AST and ALT, and decrease in BS, WBC, and BUN; lower elevation in AST and ALT at 48 h and decreased AST and ALT at 96 h were obtained when dextrose was added to commercial regular diet (Group 2). Using dextrose alone (Group 3), though there was significant elevation of AST and ALT and decrease in BUN and WBC as compared to baseline values, significant decrease in ALT, AST, and BUN as compared to control was obtained. During absolute honey feeding (Group 4), elevation in AST and ALT obtained, following CCl4 administration was significantly less than the values obtained in all other groups; with lower elevation in AST and ALT as compared to baseline values. Honey increased serum albumin, serum protein, BG, and caused lower reduction in Hb. Conclusively, exclusive honey feeding (50% concentration) significantly modifies and ameliorates biochemical and hematological changes obtained after CCl4 injection.  相似文献   
57.
We describe biodegradable mesoporous hybrid nanoparticles (NPs) in the presence of proteins and their applications for drug delivery. We synthesized oxamide phenylene‐based mesoporous organosilica nanoparticles (MON) in the absence of a silica source which had remarkably high organic content and high surface areas. Oxamide functions provided biodegradability in the presence of trypsin model proteins. MON displayed exceptionally high payloads of hydrophilic and hydrophobic drugs (up to 84 wt %), and a unique zero premature leakage without the pore capping, unlike mesoporous silica. MON were biocompatible and internalized into cancer cells for drug delivery.  相似文献   
58.
Abstract

The present work deals with the biological and phytochemical studies on Capparis decidua (Forssk) Edgew from Cholistan desert of Pakistan. Aerial and floral parts of C. decidua were collected and dried under shade. Powdered materials of each part of C. decidua were extracted with methanol separately, followed by phytochemical studies. Hexane fraction of aerial parts of the C. decidua obtained after solvent-solvent extraction was purified through repeated column chromatography by increasing order of polarity. Four compounds were purified and identified as simiarenol (1), lupeol (2), taraxerol (3) and β-sitosterol (4). Simiarenol and lupeol were isolated for the first time from genus Capparis. The structures of these compounds were established by comparing the spectroscopic data (1H NMR, 13C NMR, IR, UV & Mass spectrometry) reported in literature. The structure of 1 was further confirmed by XRD analysis. Anti-bacterial activities of crude methanolic extracts were determined against 13 bacterial strains (MIC 250-1000?μg/mL). α-Glucosidase and urease inhibitory activities of pure compounds were also determined. Compounds 1, 2 and 4 showed α-glucosidase inhibition with IC50 at 96.12?±?0.12, 65.28?±?0.13 and 128.14?±?0.17?μM, respectively.  相似文献   
59.
Ultrasound-assisted extraction (UAE) was used to extract carotenoids from the carrot pomace. To investigate the effect of independent variables on the UAE, the response surface methodology (RSM) with central-composite design (CCD) was employed. The study was conducted with three independent variables including extraction time (min), temperature (°C), and ethanol concentration (%). The results showed that the optimal conditions for UAE were achieved with an extraction time of 17 min, temperature of 32 °C, and ethanol concentration of 51% of total carotenoids (31.82 ± 0.55); extraction time of 16 min, temperature of 29 °C, and ethanol concentration of 59% for a combination of β-carotene (14.89 ± 0.40), lutein (5.77 ± 0.19), and lycopene (2.65 ± 0.12). The non-significant (p > 0.05) correlation under optimal extraction conditions between predicted and experimental values suggested that UAE is the more productive process than conventional techniques for the extraction of carotenoids from the carrot pomace.  相似文献   
60.
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