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701.
Amit K. Srivastav Bhavesh Agrawal Bhavya Swami Yadvendra K. Agrawal Prasenjit Maity 《Journal of nanoparticle research》2017,19(6):216
Alkyne {phenyl acetylene (PA) and 9-ethynylphenanthrene (EPT)}-ligated Rh nanoparticles (1 and 2, respectively) with mean diameter of 1.5 ± 0.2 nm were synthesized via a facile and high-yield biphasic ligand exchange protocol using similar sized ethylene glycol (EG)-stabilized Rh nanoparticles as precursors (EG:Rh). The synthesized organometallic Rh nanoparticles were convincingly characterized using several spectroscopic and microscopic techniques, e.g., Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), optical absorption spectroscopy (UV-Vis), photoluminescence spectroscopy (PL), powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscope (TEM). We propose that the syntheses mechanism relies on catalytic acetylenic (≡C–H, carbon–hydrogen) bond breaking by EG:Rh followed by strong metal–carbon bond formation with a vinyldiene (>C═C═M) motif. The obtained 1 and 2 showed luminescence property, which arises from ligand structure through intraparticle conjugation. Electron-rich phenanthrene-ligated Rh nanoparticles (2) showed good sensing performance for detection of electron deficient nitro-aromatic explosive molecules (NA) in solution phase through luminescence quenching method. 相似文献
702.
In this paper, the authors have studied the dynamics of a novel complex chaotic system with fractional order derivative and found the existence of chaos. The novel complex system is simulated for integer as well as fractional orders which shows some unusual phenomena. The main contribution of this effort is an implementation of the Largest Lyapunov Exponent (LLE) criteria based on Wolf’s algorithm. The conditions for chaos control based on the fractional Routh–Hurwitz stability conditions and feedback control are given. Also synchronization between a fractional order novel chaotic system and a controlled fractional order novel system using the modified adaptive projective synchronization method for different scaling matrices has been obtained. Numerical simulation results are carried out using the Adams–Bashforth–Moulton method. 相似文献
703.
A novel d.c. polarization/self-depolarization study and electret-type effect in AgI are reported. AgI pellets of varying thicknesses,
placed between two blocking (graphite) electrodes, were subjected to an external d.c. potential. A state of complete polarization
was attained within ∼10 min, irrespective of the sample thickness. At this state, the potential difference, developed across
the sample pellet as a result of polarization/accumulation of mobile Ag+ ions at the bulk/negative electrode interface, was measured experimentally. The potential difference, obtained immediately
after the removal of the external d.c. source, has been referred to as ‘instant peak potential (Vp)’. As soon as the external voltage source is switched off, a process of self-depolarization is initiated due to the chemical/self
diffusion of polarized mobile Ag+ ions throughout the bulk. ‘Vp’ gives a direct information regarding the extent of mobile ion concentration (n). ‘Vp’ measurements were carried out as a function of temperature and ‘Log Vp vs 1/T’ variation was compared with the ‘Log n vs 1/T’ Arrhenius plot, reported earlier in an entirely independent study.
The two variations are almost analogous. This, in turn, supported as an earlier assertion that the abrupt conductivity increase
in α-AgI, after β→α-phase transition at ∼147 °C, is predominantly due to the excessive increase in ‘n’. Furthermore, it has
also been revealed that the Ag+ ions play another unique role which led to the existence of ‘persistent polarization’ states in AgI. These states are identical
to the ‘electret-type effects’, observed in a number of dielectric materials. The polarization state persisted for very long
time in ‘thermally stimulated polarized’ sample. A detailed investigation of the persistence/retention of polarization in
the thermally-stimulated-polarized sample is reported. 相似文献
704.
An analysis of the repulsive softness parameter for alkali halides has been presented on the basis of the additivity rule. The softness parameters for individual ions have been obtained using data from three different sources viz. overlap data, molecular data and crystal data. The softness parameters so derived are used to evaluate the bulk modulus and its pressure dependence for 20 alkali halides with NaCl and CsCl structures adopting Smith's distortion model for repulsive interactions. Some attractive features of the present approach have been discussed in order to demonstrate its superiority over the previous work. 相似文献
705.
706.
The pyridinium molybdoarsenate membrane shows a response to pyridinium ions and can be used to determine the concentration of these ions in the range 10(-3)-1M. The potentials generated across the membrane are reproducible and the response time is less than 1 min. There is no interference from certain inorganic and organic ions. The electrode can be used in the pH range 3-6 as well as in non-aqueous medium. Small additions of cetyltrimethylammonium bromide cause large shifts in the membrane potentials. A membrane, after being treated with this surfactant, shows a wider range of response to pyridinium ions. Precipitation titration of pyridinium nitrate has been monitored by using this membrane electrode. 相似文献
707.
708.
R. M. Agrawal R. K. Asundi F.A.Sc. R. C. Naik D. Ramakrishnan Shobha Singh 《Proceedings Mathematical Sciences》1962,55(2):106-112
A single crystal of 5% Pr3+ in LaCl3 was grown by Stockbarger’s method and its absorption spectrum at 77° K. recorded in the region 4200–5400 Å on a grating spectrograph having a dispersion of 5 Å/mm. in the first order. Polarization of the absorption lines has also been obtained. In the group of lines arising from1I6 ←3H4 transition, six more lines in addition to the four previously known have been observed. Satisfactory analysis of all these ten lines is given. One additional Stark level in1I6 is established at 21407 cm.?1 withμ=1. For a few lines the polarization results obtained here do not agree with those of previous workers but fit in satisfactorily in the analysis. 相似文献
709.
Saxena S. C. und J. P. Agrawal 《Colloid and polymer science》1962,184(1):67
Ohne Zusammenfassung 相似文献
710.