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11.
I. Kazeminezhad A.C. Barnes J.D. Holbrey K.R. Seddon W. Schwarzacher 《Applied Physics A: Materials Science & Processing》2007,86(3):373-375
Template electrodeposition has been used to prepare a wide range of nanostructures but has generally been restricted to aqueous
electrolytes. We report the deposition of silver nanowires in a commercial nuclear track-etched polycarbonate template from
the nonaqueous ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) using silver electrochemically dissolved from the anode. Transmission electron microscopy (TEM) shows that the nanowires
have a very high aspect ratio with an average diameter of 80 nm and length of 5 μm. Ionic liquid electrolytes should greatly
extend the range of metals that can be electrodeposited as nanowires using templates.
PACS 81.15.Pq; 81.07.-b 相似文献
12.
We provide a model for the remarkable stability of surface nanobubbles to bulk dissolution. The key to the solution is that the gas in a nanobubble is of Knudsen type. This leads to the generation of a bulk liquid flow which effectively forces the diffusive gas to remain local. Our model predicts the presence of a vertical water jet immediately above a nanobubble, with an estimated speed of ~3.3 m/s, in good agreement with our experimental atomic force microscopy measurement of ~2.7 m/s. In addition, our model also predicts an upper bound for the size of nanobubbles, which is consistent with the available experimental data. 相似文献
13.
14.
The lattice energies of a series of organic dihydrogenphosphate salts capable of second harmonic generation (SHG) have been calculated. These calculations, coupled with empirical data, indicate that a minimum of 20–25% of the lattice energy arises from hydrogen-bond interactions. Hydrogen bonding is shown to be a strong enough force to have a profound effect on the overall packing and crystal geometry of such ionic materials, and is thus an important factor to consider for crystal engineering. 相似文献
15.
The results detail a novel methodology for the electrochemical determination of ammonia based on its interaction with hydroquinone in DMF. It has been shown that ammonia reversibly removes protons from the hydroquinone molecules, thus facilitating the oxidative process with the emergence of a new wave at less positive potentials. The analytical utility of the proposed methodology has been examined with a linear range from 10 to 95 ppm and corresponding limit-of-detection of 4.2 ppm achievable. Finally, the response of hydroquinone in the presence of ammonia has been examined in the room temperature ionic liquid 1-ethyl-3-methylimidazolium bis(trifluormethylsulfonyl)imide, [EMIM][N(Tf)2]. Analogous voltammetric waveshapes to that observed in DMF were obtained, thereby confirming the viability of the method in either DMF or [EMIM][N(Tf)2] as solvent. 相似文献
16.
Earle MJ Hakala U Hardacre C Karkkainen J McAuley BJ Rooney DW Seddon KR Thompson JM Wahala K 《Chemical communications (Cambridge, England)》2005,(7):903-905
Chloroindate(III) ionic liquids are versatile reaction media for Friedel-Crafts acylation reactions; the system is catalytic and totally recyclable, using an aqueous workup, with no leaching of the indium into the product phase. 相似文献
17.
The liquid crystalline behaviour of methyl-6-O-(n-dodecanoyl)-α-D-glucopyranoside, 1, has been characterised using X-ray diffraction and variable temperature Fourier transform infrared (FTIR spectroscopy). 1 exhibits a monotropic interdigitated smectic A phase consisting of bilayers in which the alkyl chains are overlapped. The crystal–isotropic transition is accompanied by a pronounced decrease in the strength of the hydrogen bonding network involving the sugar groups resulting in a marked change in the environment of the alkyl chains. The isotropic phase consists of disordered smectic-like domains stabilised via hydrogen bonding between the sugar groups. At the transition to the smectic A phase, a subtle change in hydrogen bonding is observed which is manifested by a change in the temperature dependence of the OH stretching peak position in the FTIR spectrum. On crystallisation, the strong hydrogen bonding network is re-established accompanied by a change in the conformational distribution of the alkyl chains. A model is proposed in which a combination of hydrogen bonding (enthalpic effects) and conformational arrangements (entropic effects) promotes initially the formation of smectic-like domains in the isotropic phase and subsequently stabilises the smectic A phase by inhibiting the microphase separation leading to the crystal phase. 相似文献
18.
平行双铂丝微电极用于铁氰化钾电流滴定法测定抗坏血酸的研究 总被引:2,自引:0,他引:2
平行双柱微电极是一种基于可逆氧化还原物质在电极间反馈扩散使得信噪比进一步增大的新型微电极,作者首次将这种电极应用于电流滴定分析中。结果显示,电极间距很小时,终点突跃变敏锐,使灵敏度进一步提高。该方法不需搅拌溶液,单次测量样品量只需约3μ1,是一种有实用价值的新方法。 相似文献
19.
The leading asymptotic term for the function that counts theeigenvalues of the Stokes operator is determined for fairlygeneral underlying bounded domains. Moreover, the remainderis estimated in terms of the fractality of the boundary of thedomain. The results obtained resemble corresponding ones forthe Dirichlet Laplacian. 1991 Mathematics Subject Classification:35P20. 相似文献
20.
Susan Anderson Kenneth R. Seddon Raymond D. Wright Alan T. Cocks 《Chemical physics letters》1980,71(2):220-223
Room-temperature electronic absorption spectra, and emission spectra at room temperature and 77 K, have been measured for the mixed ligand 2,2'-bipyndine-2-(2-pyridyl)quuioline complexes of ruthemum (II). The charge-transfer states initially populated by absorption of visible light are essentially localised on individual ligands, and there is little coupling of these ligand states. Emissions, however, occur from a single state possessing the characteristics of the pyridylquinoline ligand alone. 相似文献