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101.
Sukanta Dutta Bharti Rawat Divya Sachdeva 《The European Physical Journal C - Particles and Fields》2017,77(9):639
Adopting a model independent approach, we constrain the various effective interactions of leptophilic DM particles with the visible world from the WMAP and Planck data. The thermally averaged indirect DM annihilation cross section and the DM–electron direct-detection cross section for such a DM candidate are observed to be consistent with the respective experimental data. We study the production of cosmologically allowed leptophilic DM in association with \(Z\, (Z\rightarrow f\bar{f})\), \(f\equiv q,\,e^-,\, \mu ^-\) at the ILC. We perform the \(\chi ^2\) analysis and compute the 99% C.L. acceptance contours in the \(m_\chi \) and \(\varLambda \) plane from the two-dimensional differential distributions of various kinematic observables obtained after employing parton showering and hadronisation to the simulated data. We observe that the dominant hadronic channel provides the best kinematic reach of 2.62 TeV (\(m_\chi \) = 25 GeV), which further improves to \(\sim \)3 TeV for polarised beams at \(\sqrt{s} = 1\) TeV and an integrated luminosity of 1 ab\(^{-1}\). 相似文献
102.
Magnetic FeCo nanoparticles were successfully synthesized in a diffusion cloud chamber setup within pulsed laser deposition (PLD) equipment. The variation of morphology and size of FeCo nanoparticles with the number of laser pulses, ambient gas pressure and temperature gradient was studied. It was observed that the morphology of the nanoparticles changes from “cloud-like” fractal clusters to particle chains; average particle size increased at higher argon gas pressure. Increasing the temperature gradient considerably reduced the agglomeration of the nanoparticles. Nanoparticles deposited using the diffusion cloud chamber are found to be crystalline. 相似文献
103.
Carbon-doped alumina samples were prepared by a simple process involving melting of polycrystalline alumina powder in graphite environment. The melting was carried out using an electron gun of a vacuum deposition system meant for deposition of thin films. The samples showed excellent thermoluminescence (TL) and optically stimulated luminescence (OSL) response in the dose range 3 mGy to 1 Gy. Defect centers in the prepared material, as determined by excitation spectra, were found to be similar to those of commercial α-Al2O3:C single crystals. Samples were found to be suitable for radiation dosimetry, with a detection threshold of 50-μGy. Fading in the dark has been found to be<2% for a period of 2 months at room temperature. The variation in OSL response among the samples processed under similar conditions was found to be within ±14%. 相似文献
104.
S. Karamat J.J. Lin P. Lee S.V. Springham R.S. Rawat 《Applied Surface Science》2008,254(22):7285-7289
The structural, magnetic and optical properties of (ZnO)1−x(MnO2)x (with x = 0.03 and 0.05) thin films deposited by pulsed laser deposition (PLD) were studied. The pellets used as target, sintered at different temperatures ranging from 500 °C to 900 °C, were prepared by conventional solid state method using ZnO and MnO2 powders. The observation of non-monotonic shift in peak position of most preferred (1 0 1) ZnO diffraction plane in XRD spectra of pellets confirmed the substitution of Mn ions in ZnO lattice of the sintered targets. The as-deposited thin film samples are found to be polycrystalline with the preferred orientation mostly along (1 1 0) diffraction plane. The UV-vis spectroscopy of the thin films revealed that the energy band gap exhibit blue shift with increasing Mn content which could be attributed to Burstein-Moss shift caused by Mn doping of the ZnO. The deposited thin films exhibit room temperature ferromagnetism having effective magnetic moment per Mn atom in the range of 0.9-1.4μB for both compositions. 相似文献
105.
The spectra of the isotopes of xenon are analysed from the point of view of O(6) symmetry breaking. It is pointed out that
the excitation energies of the states 0
3
+
can be used in detecting breaking of the symmetry. The nature of symmetry breaking in 118Xe and 120Xe is indicated. 相似文献
106.
The carburizing of titanium (Ti) is accomplished by utilizing
energetic ion pulses of a 1.5 kJ Mather type dense plasma focus (DPF)
device operated in methane discharge. X-ray diffraction (XRD)
analysis confirms the deposition of polycrystalline titanium carbide
(TiC). The samples carburized at lower axial and angular positions
show an improved texture for a typical (200)TiC plane.
The Williamson--Hall method is employed to estimate average crystallite
size and microstrains in the carburized Ti surface. Crystallite size
is found to vary from ~ 50 to 100~nm, depending on the deposition
parameters. Microstrains vary with the sample position and hence ion
flux, and are converted from tensile to compressive by increasing
the flux. The carburizing of Ti is confirmed by two major doublets
extending from 300 to 390~cm-1 and from 560 to 620~cm-1 corresponding to acoustic and optical active modes in Raman
spectra, respectively. Analyses by scanning electron
microscopy/energy dispersive x-ray spectroscopy (SEM/EDS) have
provided qualitative and quantitative profiles of the carburized
surface. The Vickers microhardness of Ti is significantly improved after
carburizing. 相似文献
107.
An investigation on the possibility of enhancement of soft X-ray (SXR) (900–1600 eV) emission from a fast miniature plasma focus (FMPF) device of 235 J (at 14 kV) storage energy through doping of operating gas was performed. Neon (Ne), the operating gaseous medium, was doped with krypton (Kr) in different volumetric ratios at various operating pressures ranging from 2 to 14 mbar. The 1% Kr doping increased the average optimum SXR emission efficiency from 0.47% to 0.6% without enhancing the hard X-ray (HXR) (>1600 eV) emission. The Kr doping influenced the major pinching characteristics such as focusing efficiency and time to pinch with consequential effect on X-ray emissions. Synchronous operation of the 4 pseudo-spark gap (PSG) switches was mandatory for efficient discharge current delivery to the electrodes. A drastic improvement in the pinching efficiency was obtained with replacement of old and worn out PSG switches with the new ones. Optical imaging of current sheath dynamics was performed using gated ICCD camera to verify the normal operation of the device after the PSGs replacement. A numerical simulation analysis on the 2 cm long stainless steel tapered anode, used in this study, was done to predict the maximum SXR emission efficiency and the peak operating gas pressure. An analysis on the amount of SXR fluence generated at the source position and the proportion of it reaching the target position is also reported. 相似文献
108.
Michaela Ritter Anat Molad Varun Rawat Christian Limberg 《Supramolecular chemistry》2014,26(7-8):530-537
The synthesis and characterisation of an asymmetrically substituted calix-triazole ligand are reported. The ligand reacts with the Fe(II) precursor Fe2Mes4 to yield an iron(II) calixarene complex that is oxidised by dioxygen to provide a dinuclear Fe(III) compound featuring an oxido bridge. 相似文献
109.
A highly efficient and sustainable approach for the multi-component synthesis of biologically important 3-amino alkylated indoles has been investigated via Mannich-type reaction under catalyst-free, ethylene glycol as a recyclable promoting medium. The wide applicability of the present method was examined with various substrates viz substituted aldehydes, indoles and secondary amines. This method will be useful for a large scale synthesis of 3-amino alkylated indoles without the use of column chromatography. The present method provides higher environmental compatibility and sustainability factors such as smaller E-factor (0.433) and higher atom-economy (AE = 93.3%). 相似文献
110.
PC. M. Gubbens G. J. Boender A. M. van der Kraan K. H. J. Buschow 《Hyperfine Interactions》1992,68(1-4):329-332
DyFe12?xMx (M=Si,Ti,Cr) were studied with57Fe and161Dy Mössbauer spectroscopy. The deduced coupling constants JRFe of these compounds are about equal. It is found that Si is substituting one particular Fe-site, while Cr is substituting Fe randomly. In DyFe10Si2 two Fe-sites favour a c-axis anisotropy, while the third one favours the basal plane. 相似文献