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121.
A. Swinnen I. Haeldermans M. vandeVen J. D'Haen G. Vanhoyland S. Aresu M. D'Olieslaeger J. Manca 《Advanced functional materials》2006,16(6)
A new ordered structure of the C60 derivative PCBM is obtained in thin films based on the blend PCBM:P3HT, as detailed by Swinnen, Manca, and co‐workers on p. 760. Needlelike crystalline PCBM structures, whose dimensions and spatial distribution ca be tuned by adjusting the blend ratio and annealing conditions, are formed. In typical solar‐cell applications of these blended films, these results indicate that during long‐term operation under normal conditions (50–70 °C) morphology changes and a decrease in cell performance could occur. A new ordered structure of the C60 derivative PCBM ([6‐6]‐phenyl C61‐butyric acid methyl ester) is obtained in thin films based on the blend PCBM:regioregular P3HT (poly(3‐hexylthiophene)). Rapid formation of needlelike crystalline PCBM structures of a few micrometers up to 100 μm in size is demonstrated by submitting the blended thin films to an appropriate thermal treatment. These structures can grow out to a 2D network of PCBM needles and, in specific cases, to spectacular PCBM fans. Key parameters to tune the dimensions and spatial distribution of the PCBM needles are blend ratio and annealing conditions. The as‐obtained blended films and crystals are probed using atomic force microscopy, transmission electron microscopy, selected area electron diffraction, optical microscopy, and confocal fluorescence microscopy. Based on the analytical results, the growth mechanism of the PCBM structures within the film is described in terms of diffusion of PCBM towards the PCBM crystals, leaving highly crystalline P3HT behind in the surrounding matrix. 相似文献
122.
D.K. Yu R.Q. Zhang S.T. Lee 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,15(1):57-63
The structures and energetics of carbon bridged C60 clusters (C
60
)
n
Cm have been studied by simulated annealing technique within the tight-binding molecular-dynamics. The “sp2 addition” ball-and-chain dimers exhibit odd-even alternations over the number of chain atoms, with the dimers containing
even chain atoms more stable against dissociation than their immediate neighbors containing odd chain atoms. In addition to
the usual “sp2 addition” dimers, a pentagon-linked C121 isomer and a hexagon-linked C122 isomer are also found to be stable. Based on our tight-binding calculations, trimers and larger clusters can be simply regarded
as being made up of independent or weakly interacting dimers, if the C-C60 joints on a single cage are not too close to each other. Large C60 clusters connected by chains each containing only one or two carbon atoms have similar stability to that of constituent dimers,
indicating the possibility to form stable C60-carbon polymers.
Received 17 January 2001 and Received in final form 26 February 2001 相似文献
123.
F. Uhlík Z. Slanina E. Ōsawa 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):349-352
The five isolated-pentagon-rule (IPR) satisfying isomers of C78, labeled 1-5, or according to symmetry as D3, C2v, C'
2v
, D3h, and D'
3h
, are computed. The cage geometries are optimized at the ab initio HF level with the standard 3-21G basis set (HF/3-21G). The separation energetics is then computed using the B3LYP density-functional
treatment in the standard 6-31G* basis set (B3LYP/6-31G*//HF/3-21G). Harmonic vibrational frequencies are calculated by the
SAM1 semiempirical method. The computed energies, structural and vibrational data are employed in the construction of isomeric
partition functions and evaluation of the relative Gibbs free energies. The results are converted into relative concentrations
for a wide temperature interval. The C'
2v
structure is the most populated throughout while the D3h species is negligible at all temperatures. The agreement between theory and experiment is reasonable, though some aspects
are still to be clarified.
Received 28 November 2000 相似文献
124.
I. Compagnon R. Antoine D. Rayane Ph. Dugourd M. Broyer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):365-368
Gas phase Ti-C60 clusters are studied by molecular beam electric deflection. The permanent dipole moment of the TiC60 molecule is determined. It is equal to 8.1±1.5
D. This dipole is due to a transfer of electron from the transition metal atom to the C60 cage. No dipole is observed for Ti(C60)2 molecules. This is in agreement with the symmetrical dumbbell-like structure that has been previously proposed.
Received 22 November 2000 相似文献
125.
Ferromagnetic behavior of polymerized fullerenes appears quite close to the boundary where the fullerene molecules are destroyed. However, when the presence of a disordered or graphitic phase is detectable by the standard characterisation methods, the ferromagnetic features quickly disappear. 相似文献
126.
《Electroanalysis》2017,29(3):696-701
Three non‐covalent metallotetraphenylporphyrin/fullerene (MTPPS4 (M=Zn2+, Fe2+, Co2+)/C60) nanocomposites were prepared by π‐π molecular interaction and characterized by scanning electron microscopy and UV‐Vis absorption spectroscopy. Electrocatalytic studies indicated that the MTPPS4/C60 nanocomposites which were embedded in TOAB film on the glassy carbon electrode (GCE) (TOAB/MTPPS4/C60/GCE) exhibited a high electrocatalytic activity for H2O2. MTPPS4 enhanced the electrocatalytic ability of C60 in the increasing order of TOAB/ZnTPPS4/C60/GCE, TOAB/FeTPPS4/C60/GCE and TOAB/CoTPPS4/C60/GCE. The measurement with the differential pulse voltammetry (DPV) exhibited that there is a well‐defined linear relationship between the reduction currents and H2O2 concentrations in the range from 0.3 to 1.0 mM, with the detection limit of 0.07 mM at the TOAB/ZnTPPS4/C60/GCE electrode, of 0.08 mM at the TOAB/FeTPPS4/C60/GCE electrode, of 0.04 mM at the TOAB/CoTPPS4/C60/GCE electrode, respectively. The biosensors showed a good anti‐interfering ability towards glucose, ascorbic acid and L‐cysteine and a high potential practicality. 相似文献
127.
As the list of known carbon compounds grows longer, solvated fullerenes have become a more important class of carbon materials. Their general properties and methods of synthesis have both attracted considerable attention. The study of the behavior of these compounds under high-pressure conditions has revealed several new phenomena that have never been observed in pure fullerene. This article is a review of all recent progress in this field. 相似文献
128.
129.
Parham Yaghoobi 《Solid State Communications》2011,151(17):1105-1108
Light-induced heating of a typical bulk conductor to thermionic electron emission temperatures usually requires high-power lasers. This is because of the efficient dissipation of heat generated at the illuminated spot to the surroundings, since electrical conductors are normally also good thermal conductors. We show that the situation can be drastically different in a carbon nanotube forest and a spot on the surface of the forest can be heated to above 2000 K using a low-power beam of visible light, leading to localized thermionic electron emission. This unique phenomenon may be explained by a rapid drop in thermal conductivity with increase in temperature, leading to a positive feedback that thermally isolates an island on the forest. Applications include thermoelectrics, photocathodes, optical switches, solar cells and even solar displays. 相似文献
130.
Zheng Xu Li‐Min Chen Guanwen Yang Chun‐Hao Huang Jianhui Hou Yue Wu Gang Li Chain‐Shu Hsu Yang Yang 《Advanced functional materials》2009,19(8):1227-1234
A method which enables the investigation of the buried interfaces without altering the properties of the polymer films is used to study vertical phase separation of spin‐coated poly(3‐hexylthiophene) (P3HT):fullerene derivative blends. X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) analysis reveals the P3HT enrichment at the free (air) surfaces and abundance of fullerene derivatives at the organic/substrate interfaces. The vertical phase separation is attributed to the surface energy difference of the components and their interactions with the substrates. This inhomogeneous distribution of the donor and acceptor components significantly affects photovoltaic device performance and makes the inverted device structure a promising choice. 相似文献