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81.
The samples of natural mica (muscovite and biotite) were irradiated with energetic heavy ions [136Xe (11.56 MeV/n) and 197Au (11.40 MeV/n)] from universal linear accelerator (UNILAC) GSI, Darmstadt, Germany. The simple track etch technique has been used to develop and analyze the morphology of induced heavy ions and natural alpha recoil tracks with the help of atomic force microscopy. Defective structure and lattice disorder have been observed in the environs of the etch pits in these layered crystalline materials. The distribution of defects produced along the tracks, geometrical analysis of tracks shapes and shallowness and their correlations with the structural arrangement of the materials have been discussed in the present investigation. Importance of different ion track geometries in micaceous minerals for the fabrication of nanoterrace material with different stacks having sharp edges with unique properties has been elaborated in the present paper. 相似文献
82.
To the best of our knowledge till now there is no method in the literature to find the exact fuzzy optimal solution of unbalanced
fully fuzzy transportation problems. In this paper, the shortcomings and limitations of some of the existing methods for solving
the problems are pointed out and to overcome these shortcomings and limitations, two new methods are proposed to find the
exact fuzzy optimal solution of unbalanced fuzzy transportation problems by representing all the parameters as LR flat fuzzy numbers. To show the advantages of the proposed methods over existing methods, a fully fuzzy transportation problem
which may not be solved by using any of the existing methods, is solved by using the proposed methods and by comparing the
results, obtained by using the existing methods and proposed methods. It is shown that it is better to use proposed methods
as compared to existing methods. 相似文献
83.
Andrew K. Johnson Jozef Kaczor Hongmei Han Maninder Kaur Guoxin Tian Linfeng Rao You Qiang Andrzej J. Paszczynski 《Journal of nanoparticle research》2011,13(10):4881-4895
The creation of multifunctional nanomaterials by combining organic and inorganic components is a growing trend in nanoscience. The unique size-dependent properties of magnetic nanoparticles (MNPs) make them amenable to numerous applications such as carriers of expensive biological catalysts, in magnetically assisted chemical separation of heavy metals and radionuclides from contaminated water sources. The separation of minor actinides from high-level radionuclide waste requires a sorbent stable in acidic pH, with ease of surface functionalization, and a high capacity for binding the molecules of interest. For the described experiments, the MNPs with 50 nm average size were used (size distribution from 20 to 100 nm and an iron content of 80–90 w/w%). The MNPs that have been double coated with an initial silica coating for protection against iron solubilization and oxidation in nitric acid solution (pH 1) and a second silica/polymer composite coating incorporating partially imbedded poly(allylamine) (PA). The final product is magnetic, highly swelling, containing >95% water, with >0.5 mmol amines g?1 available for functionalization. The amine groups of the magnetic resin were functionalized with the chelating molecules diethylenetriaminepentaacetic acid (DTPA) and N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) for separation of minor actinides from used nuclear fuel. 相似文献
84.
The interplay between spectator and participant matter in heavy-ion collisions is investigated within the isospin-dependent
quantum molecular dynamics (IQMD) model in terms of the rapidity distribution of light charged particles. The effect of different
types and sizes of rapidity distributions is studied in elliptical flow. The elliptical-flow patterns show the important role
of nearby spectator matter on the participant zone. This role is further explained on the basis of the passing time of the
spectator and the expansion time of the participant zone. The transition from in-plane to out-of-plane emission is observed
only when the mid-rapidity region is included into the rapidity bin. Otherwise no transition occurs. The transition energy
is found to be highly sensitive to the size of the rapidity bin, while it is only weakly dependent on the type of the rapidity
distribution. These theoretical findings are found to be in agreement with experimental results. 相似文献
85.
Gurinder Pal SinghParvinder Kaur Simranpreet KaurD.P. Singh 《Physica B: Condensed Matter》2011,406(24):4652-4656
Glass samples of composition xAl2O3-20PbO-(80−x)B2O3 and xWO3-xAl2O3-20PbO-(80−2x)B2O3 with x varying from 0% to 10% mole fraction are prepared by melt quench technique. The optical band gap decreases (from 3.21 to 2.37 eV) more for WO3-Al2O3-PbO-B2O3 glasses with an addition of WO3 content. The FTIR spectral studies have pointed out the conversion of structural units of BO3 to BO4 and WO4 to WO6 in these glasses. The increase in density from 4.51 to 5.80 g cm−3 for WO3-Al2O3-PbO-B2O3 glasses is observed with an increase in WO3 content. This is observed that the atomic structure changes more with the incorporation of WO3. This is due to the formation of WO6, WO4 and BO4 units. 相似文献
86.
Surinder Singh Jatinder SinghSandeep Singh Gill 《Optics and Lasers in Engineering》2011,49(1):152-158
Employing a Mach-Zehnder Interferometer (MZI), this paper describes simulation demonstration of an all-optical scheme for data format conversion between non-return-to-zero (NRZ) and return-to-zero (RZ). Data format conversion between NRZ and RZ at 120 Gb/s has been simulated for the first time using an MZI. In addition, we have proposed for the first time data format conversion from NRZ to RZ by using a single SOA in an MZI. 相似文献
87.
CrSiN coatings were deposited on stainless steel (Grade: SA304) and silicon Si(1 0 0) substrates, with varying argon-nitrogen gas proportions and deposition temperature, using reactive magnetron sputtering technique in the present work. The influence of sputtering (Ar) and reactive gas proportions (N2) and temperature on the structural properties of the CrSiN coating was investigated. A small amount of silicon content (3.67 at.% Si) plays a crucial role in addition to the nitrogen content for the formation of different phases in the CrSiN coatings as observed in the present work. For example, the coating with comparatively low nitrogen content, 40% N2, during deposition, formed a crystalline structure consisting of nano-crystalline CrN which is separated by an amorphous SiN phase, as evident from X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The formation of CrN(1 1 1) and Cr2N(1 1 1) phases has occurred at 30% N2 with 3.67% Si content, which transformed in to CrN(1 1 1) and CrN(2 0 0) with increase in N2 content but with same Si content. The surface topography and morphology of the coatings were analyzed by atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM), respectively. A less columnar growth is observed in CrSiN coatings deposited at low argon content, Ar:N2 (20:80), and with 3.67 at.% Si in the coatings. However, it becomes dense with increase in nitrogen content and temperature. The XRD analysis showed that the intensity of a dominating peak (1 1 1) is decreasing from (80:20) to (60:40) argon:nitrogen environment. With a further increase of nitrogen content, from (60:40), in the sputtering gas mixture, to (40:60) argon-nitrogen, there is a sudden increase in (1 1 1) peak and above (40:60), the peak reduction rate is very slow than the previous one. The (1 1 1) and (2 0 0) peak intensity variations are very limited due to high nitrogen content, above 50%, and considerable amount of Si atoms, 3.67 at.%, present in the CrN coatings. 相似文献
88.
Inderpreet Singh A. Verma I. Kaur L. M. Bharadwaj V. Bhatia V. K. Jain C. S. Bhatia P. K. Bhatnagar P. C. Mathur 《Journal of Polymer Science.Polymer Physics》2010,48(1):89-95
DC conductivity of conjugated polymer‐single‐walled carbon nanotube (SWNT) composite films has been measured for different SWNT concentrations. The composite was prepared by dispersing SWNTs in the poly (3‐octylthiophene), P3OT matrix already dissolved in xylene. The conductivity of the composite films showed a rapid increase as the SWNT concentration increases beyond a certain value. This behavior is explained in terms of percolating paths provided by the SWNTs in the volume of polymer matrix. To investigate the effect of length of nanotubes on the percolation conductivity, different SWNT samples were employed with similar diameter but varying tube lengths. It was found that the conductivity of the composite films is strongly dominated by the length of the nanotubes. Lower percolation limit and high conductivity value of composite films is observed for longer nanotubes. Furthermore, the conductivity is observed to be dependent on the size of the host polymer molecule also. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 89–95, 2010 相似文献
89.
Jyotsna Galgale Nupinder Kaur Preeti Singh Manik Manake N. K. Gaur R. K. Singh 《Pramana》2004,63(2):413-417
An extended three-body force shell model (ETSM) has been applied to investigate the static and dynamic properties of KCN
x
Cl1−x
for the compositionx = 0.56 and 1.0 at 300 K. The phonon dispersion curves computed by us are compared with the single crystal neutron diffraction
data. The unusual features of these curves are the upward curvature seen in some of the acoustic branches. This is a result
ofK-dependent softening of the phonon due to translation-rotation coupling. The transverse acoustic branch is more soft near
the zone centre. 相似文献
90.