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991.
S.-M. Lai J.-L. Liu C.-Y. Huang Wei-Jen Lai Jiun-Wei Zeng K.-C. Cheng 《Journal of Macromolecular Science: Physics》2013,52(10):1355-1371
A near infrared reflective (NIR, nickel antimony titanium yellow rutile) pigment filler was incorporated into a polyethylene terephthalate (PET) matrix via a melt blending approach to increase the infrared reflection of PET and limit the thermal heat accumulation in light of environmental and energy conservation concerns. Two different types of surface modifiers, polyethylene glycol (PEG) and cetyltrimethylammonium bromide (CTAB), were used to modify the NIR surface, as NIR–PEG and NIR–CTAB fillers, to investigate the surface modification effect. Fourier transform infrared spectroscopy (FTIR), a Zetasizer, and electron spectroscopy for chemical analysis (ESCA) results suggested a successful adsorption of the organic modifiers onto the NIR surface. Thermogravimetric analysis indicated a higher adsorption degree for the CTAB modifier than the PEG modifier due to the electronic interaction between CTAB and NIR. The thermal crystallization temperature (Tc) for neat NIR-filled samples decreased with increasing NIR content within the PET matrix at first, up to 9°C, but then tended to increase again up to a measurable difference of 6°C with respect to pure PEG, indicating the promotion of the crystallization kinetics of the neat NIR within the PET matrix. On the other hand, a decrease in Tc for all NIR-CTAB or NIR-PEG loadings was found, with the depression close to 10°C for all NIR-CTAB samples regardless of the loading. CTAB modified NIR gave the highest improvement in tensile strength and strain at break in comparison with NIR and NIR-PEG filled samples. The near infrared reflection values of modified PET were higher than those of neat PET. The reflection values appeared to be the highest for some concentrations of the NIR-CTAB filled samples, but were of similar orders of magnitude with those for NIR or NIR-PEG filled samples. 相似文献
992.
Aya C. Taki Joseph J. Byrne Peter R. Boag Abdul Jabbar Robin B. Gasser 《Molecules (Basel, Switzerland)》2021,26(14)
In the present study, we established a practical and cost-effective high throughput screening assay, which relies on the measurement of the motility of Caenorhabditis elegans by infrared light-interference. Using this assay, we screened 14,400 small molecules from the “HitFinder” library (Maybridge), achieving a hit rate of 0.3%. We identified small molecules that reproducibly inhibited the motility of C. elegans (young adults) and assessed dose relationships for a subset of compounds. Future work will critically evaluate the potential of some of these hits as candidates for subsequent optimisation or repurposing as nematocides or nematostats. This high throughput screening assay has the advantage over many previous assays in that it is cost- and time-effective to carry out and achieves a markedly higher throughput (~10,000 compounds per week); therefore, it is suited to the screening of libraries of tens to hundreds of thousands of compounds for subsequent evaluation and development. The present phenotypic whole-worm assay should be readily adaptable to a range of socioeconomically important parasitic nematodes of humans and animals, depending on their dimensions and motility characteristics in vitro, for the discovery of new anthelmintic candidates. This focus is particularly important, given the widespread problems associated with drug resistance in many parasitic worms of livestock animals globally. 相似文献
993.
ABSTRACT The investigation of regular F-abundant semigroups is initiated. In fact, F-abundant semigroups are generalizations of regular cryptogroups in the class of abundant semigroups. After obtaining some properties of such semigroups, the construction theorem of the class of regular F-abundant semigroups is obtained. In addition, we also prove that a regular F-abundant semigroup is embeddable into a semidirect product of a regular band by a cancellative monoid. Our result is an analogue of that of Gomes and Gould on weakly ample semigroups, and also extends an earlier result of O'Carroll on F-inverse semigroups. 相似文献
994.
N. Tigau 《Crystal Research and Technology》2008,43(9):964-969
Thin films of antimony trisulfide (Sb2S3) were prepared by thermal evaporation under vacuum (p=5×10–5 torr) on glass substrates maintained at various temperatures between 293 K and 523 K. Their microstructural properties have obtained by transmission electron microscopy (TEM). The electron diffraction analysis showed the occurrence of amorphous to polycrystalline transition in the films deposited at higher temperature of substrates (523 K). The polycrystalline thin films were found to have an orthorhombic structure. The interplanar distances and unit‐cell parameters were determined by high‐resolution transmission electron microscopy (HRTEM) and compared with the standard values for Sb2S3. The surface morphology of Sb2S3 thin films was investigated by scanning electron microscopy (SEM). The optical transmission spectra at normal incidence of Sb2S3 thin films have been measured in the spectral range of 400–1400 nm. The analysis of the absorption spectra revealed indirect energy gaps, characterizing of amorphous films, while the polycrystalline films exhibited direct energy gap. From the photon energy dependence of absorption coefficient, the optical band gap energy, Eg, were calculated for each thin films. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
995.
B. Xu X. Li J. Sun L. Yi 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,66(4):483-487
Using first-principles calculations based on density-functional theory in
its local-density approximation, we investigated the Electronic structure,
ferroelectricity and optical properties of CaBi2Ta2O9 (CBT)
for the first time. It is found that CBT compound has an indirect band gap
of 3.114 eV and the O 2s and 2p states are strongly hybridized with the 6s
states of Bi which belong to the (Bi2O2)2+ planes. The quite
strong Ta–O and Bi–O hybridization is the primary source for
ferroelectricity. Our results imply that the interaction between Bi and O is
highly covalent. The anisotropy occurs mainly above 4 eV in the optical
properties. The different optical properties have been discussed. 相似文献
996.
A. F. Al Alam S. F. Matar N. Ouaini M. Nakhl 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(4):491-498
Investigations within the local spin density functional theory (LSDF) of the intermetallic hydride system CeRhSnHx were carried out for discrete model compositions in the range 0.33 ≤xH ≤ 1.33 with the purpose of assessing the change of the cerium valence state in the neighborhood of the experimental hydride
composition, CeRhSnH0.8. In agreement with experiment, the analyses of the electronic and magnetic structures and of the chemical bonding properties
point to trivalent cerium for 1 ≤xH ≤ 1.33. In contrast, for lower hydrogen amounts the hydride system stays in an intermediate-valent state for cerium, like
in CeRhSn. The influence of the insertion of hydrogen is addressed from both the volume expansion and chemical bonding effects.
The latter are found to have the main influence on the change of Ce valence character. Spin polarized calculations point to
a finite magnetic moment carried by the Ce 4f states; its magnitude increases with xH in the range 1 ≤xH ≤ 1.33. 相似文献
997.
Ya Zhang Kailimai Su Yingshuang Ha Weifeng Chen Chenghua Sun 《Analytical letters》2019,52(12):1888-1899
Molecular imprinting and surface enhanced Raman scattering (SERS) were used to prepare a core-shell Ag@molecularly imprinting polymer (MIP) for the determination of p-nitroaniline. The obtained Ag@MIP exhibits a detection limit of 10?12 M, which demonstrates higher sensitivity toward p-nitroaniline than conventional approaches. In addition, the Ag@MIP shows good recyclability, and simultaneously offers better stability and high SERS activity for recognizing target molecules. To characterize the high SERS activity of the SERS-MIP hybrid material, a possible mechanism for the SERS substrate is proposed involving enhancement by the MIP. This study is expected to provide an alternative approach for the determination of p-nitroaniline in aqueous environments. 相似文献
998.
Andreea Antonia Georgescu Andreea Eliescu Cristina Mihaela Nicolescu Marius Bumbac Nicoleta Cioateră 《Analytical letters》2019,52(13):2007-2027
The capacities of Pleurotus ostreatus mushroom and spent substrate were evaluated for the biosorption of cadmium (II) from aqueous solution in order to select the most efficient material for bioremediation. The optimum sorption conditions were optimized, including the pH of the aqueous solution, contact time, biomass dosage, initial metal concentration, and temperature. The sorption of cadmium on both biosorbents was also evaluated by several kinetic, equilibrium, and thermodynamic models. The possible heavy metal biosorption mechanisms were evaluated through point of zero charge (pHpzc), Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDX). Based on the results of column studies, the effectiveness of the P. ostreatus spent substrate was confirmed as a biosorbent for Cd(II) removal from aqueous solutions. 相似文献
999.
Andreas Herburger Dr. Milan Ončák Dr. Chi-Kit Siu Ephrem G. Demissie Jakob Heller Dr. Wai Kit Tang Prof. Dr. Martin K. Beyer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(43):10165-10171
Understanding the intrinsic properties of the hydrated carbon dioxide radical anions CO2.−(H2O)n is relevant for electrochemical carbon dioxide functionalization. CO2.−(H2O)n (n=2–61) is investigated by using infrared action spectroscopy in the 1150–2220 cm−1 region in an ICR (ion cyclotron resonance) cell cooled to T=80 K. The spectra show an absorption band around 1280 cm−1, which is assigned to the symmetric C−O stretching vibration νs. It blueshifts with increasing cluster size, reaching the bulk value, within the experimental linewidth, for n=20. The antisymmetric C−O vibration νas is strongly coupled with the water bending mode ν2, causing a broad feature at approximately 1650 cm−1. For larger clusters, an additional broad and weak band appears above 1900 cm−1 similar to bulk water, which is assigned to a combination band of water bending and libration modes. Quantum chemical calculations provide insight into the interaction of CO2.− with the hydrogen-bonding network. 相似文献
1000.