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11.
The green method of nanoparticle synthesis, which is an environment and living-friendly method, is an updated subject that has appeared as an alternative to conventional methods such as physical and chemical synthesis. In this presented study, the green synthesis of magnetic iron oxide nanoparticles (IONPs) from iron (III) chloride by using Brassica oleracea var. capitata sub.var. rubra aqueous peel extract has been reported. The prepared IONPs were characterized with fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-VIS), zeta potential, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The cytotoxic effects of IONPs on MCF-7 breast cancer cell line were studied by MTT assay, and migrative effect of its were carried out by the wound healing assay. It was found that the mean particle size of IONPs was 675 ± 25 nm, and the polydispersity index was 0.265 PDI. It was also determined that these nanoparticles had an anti-proliferative impact on the MCF-7 breast cancer cell line depending on the dosage. Characterization results support the successful synthesis of nanoparticles, and the dose-dependent cytotoxic effects of nanoparticles on MCF-7 cells also make it a potential chemotherapeutic agent for breast cancer treatment.  相似文献   
12.
The modified simple equation method is an interesting technique to find new and more general exact solutions to the fractional differential equations in nonlinear sciences. In this paper, the method is applied to construct exact solutions of (2+1)-dimensional conformable time-fractional Zoomeron equation and the conformable space-time fractional EW equation.  相似文献   
13.
The γ-selective allylation of catalytic and stoichiometric alkylzinc-cuprates have been kinetically studied. The reactivity profiles generated by allylation reactions of n-butylzinc chloride catalyzed by CuX compounds (X = I, Br, Cl, CN, SCN) and also catalyzed by n-butylzinc-copper reagents and di n-butylzinc-copper reagents were evaluated. Reactivity profiles for allylation of stoichiometric n-butylzinc-copper reagents and di n-butylzinc-copper reagents were also prepared. All CuX compounds have been screened for the preparation of Grignard reagent derived n-butylzinc-copper reagents and di n-butylzinc-copper reagents.The evaluation of the profiles indicates that the active catalyst might be RCu(X)ZnCl and also to some degree, R2CuZnCl · ZnClX, which both could favor formation of γ-product. All data supports the reductive elimination of σ-allyl Cu (III) complex formed at vinylic terminal to give γ-allylated product with a quite slow isomerization to σ-allyl Cu (III) complex formed at allylic terminal to give α-allylated product. In the allylation mechanism of zinc cuprates, the role of counter ion, ZnCl+ has been discussed.  相似文献   
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We present herein a new nanocatalyst, namely binary CuPt alloy nanoparticles (NPs) supported on reduced graphene oxide (CuPt‐rGO), as a highly active heterogeneous catalyst for the transfer hydrogenation (TH) protocol that is demonstrated to be applicable over the reduction of various unsaturated organic compounds (olefins, aldehydes/ketones and nitroarenes) in aqueous solutions at room temperature. CuPt alloy NPs were synthesized by the co‐reduction of metal (II) acetylacetonates by borane‐tert‐butylamine (BTB) complex in hot oleylamine (OAm) solution and then assembled on reduced graphene oxide (rGO) via ultrasonic‐assisted liquid phase self‐assembly method. The structure of yielded CuPt NPs and CuPt‐rGO nanocatalyst were characterized by TEM, XRD and ICP‐MS. The activity of Cu7Pt3‐rGO nanocatalysts were then tested for the THs that were conducted in a commercially available high‐pressure tube using water as sole solvent and ammonia borane as a hydrogen donor at room temperature. The presented catalytic TH protocol was successfully applied over nitroarenes, olefines and aldehydes/ketones, and all the tested compounds were converted to corresponding reduction products with the yields reaching up to 99% under ambient conditions. Moreover, the Cu7Pt3‐rGO nanocatalyst was also reusable in the TH by providing 99% yield after five consecutive runs in TH of nitrobenzene as an example.  相似文献   
16.
Reaction of methyl arylzincs with acetone O‐(mesitylenesulfonyl)oxime in THF in the presence of CuCN at room temperature is efficient in selective electrophilic amination of aryl carbanions. This procedure allows for the preparation of arylamines in moderate to good yields and provides an efficient and atom economic alternative to existing amination methods for diarylzincs. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Arteriovenous malformations (AVM) of the brain, errors in the development of the vasculature, produce high flow arteriovenous shunts. They steal blood from surrounding brain tissue, which is chronically hypoperfused. Hypoperfusion is a condition of inadequate tissue perfusion and oxygenation resulting in abnormal tissue metabolism. In the present study Fourier transform infrared (FTIR) spectroscopy was used to investigate the effects of hypoperfusion on rat cranial bone mineral and organic matrix at the molecular level. FTIR spectroscopic analysis revealed that in cranial bones of an experimental group the relative amount of carbonate and phosphate groups increased whereas that of protein (amide I) decreased. Curve-fitting analysis of the v2 carbonate band showed that amounts of type A and type B carbonates increased slightly (p=0.423 for both) whereas, type L carbonate decreased slightly (p=0.522) in hypoperfused cranial bones. Analysis of the C–H region revealed a significant increase (p=0.037) in the lipid to protein ratio. Because the lipid content is high, hypoperfused cranial bone tissue is more prone to lipid peroxidation. Dialdehydes derived from lipid peroxidation can make cross-links with collagen and might lead to disturbances in the collagen cross-link profile. The 1660 cm–1/1690 cm–1 partial area ratio derived from curve-fitting analysis of the Amide I band is sensitive to the relative amount of collagen non-reducible cross-link hydroxylysyl/lysylpyridinolines (Pyr) and reducible cross-link dihydroxylysinonorleucine (DHLNL) and this ratio reflects collagen maturity. In chronic hypoperfusion a significant decrease (p=0.004) was observed in this ratio. This means there were less mature collagen cross-links. Disturbances in the collagen maturation can affect mineralization process and lead to formation of pathologic structures in cranial bones. These findings clearly demonstrate that FTIR spectroscopy can be used to extract valuable information at molecular level, leading to better understanding of the effect of hypoperfusion on rat cranial bones.  相似文献   
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Probabilistic evolution theory (PREVTH) is used for the solution of initial value problems of first order explicit autonomous ordinary differential equation sets with second degree multinomial right hand side functions. It is an approximation method based on Kronecker power series: a rewriting of multivariate Taylor series using matrices having certain flexible parameters. Kronecker power series have matrices which are called telescope matrices: \(n \times n^{j+1}\) matrices where j is the index of summation. The additive terms of each telescope matrix is formed through Kronecker product from both sides by Kronecker powers of identity matrices. Recently, squarification is proposed in order to avoid the growing of the matrices in size at each additive term of the series. This paper explains the squarification procedure: the procedure used in order to avoid Kronecker multiplications within PREVTH so that the sizes of the matrices do not grow and so that the amount of necessary computation is reduced. The recursion between squarified matrices is also given. As a numerical application, the solution of a Hénon–Heiles system is provided.  相似文献   
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