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101.
Yoshinori Namihira Md. Anwar Hossain Taito Koga Md. Ashraful Islam S. M. Abdur Razzak Shubi F. Kaijage Yuki Hirako Hiroki Higa 《Optical Review》2012,19(2):78-81
In this paper, we propose a highly nonlinear dispersion flattened hexagonal photonic crystal fiber (HNDF-HPCF) with nonlinear
coefficients as large as 57.5W−1 km−1 at 1.31 μm wavelength for dental optical coherence tomography (OCT) applications. This HNDF-HPCF offers not only large nonlinear
coefficient but also very flat dispersion slope and very low confinement losses. Using these characteristics of our proposed
PCF, it is shown through simulations by using finite difference method with an anisotropic perfectly matched boundary layer
that this PCF offers the efficient supercontinuum (SC) generation for dental OCT applications at 1.31 μm wavelength using
a picosecond pulse easily produced by commercially available less expensive laser sources. Coherent length of light source
using SC is found 10 μm and the spatial resolutions in the depth direction for dental applications of OCT are found about
6.1 μm for enamel and 6.5 μm for dentin. 相似文献
102.
103.
We present a highly nonlinear non-circular core photonic crystal fiber (HNL-NCPCF) with all normal group velocity dispersion (GVD) to design a supercontinuum (SC) light source for optical coherence tomography (OCT) system. Nonlinear coefficient is increased as large as 66 W?1 km?1 at by reducing the effective mode area and core is made non-circular to increase birefringence by putting the square lattice of air-holes inside the silica host. About 85 nm 10 dB spectral bandwidths for 2.5 ps input optical pulse and 140 nm 10 dB spectral bandwidths for 1.0 ps input optical pulse have been observed using the same fiber length of 200 m and input optical power of 15 W. Coherent lengths of the generated supercontinuum light sources are found for 2.5 ps input optical pulse and for 1.0 ps input optical pulse. Therefore, the highest longitudinal resolution for dental OCT at is found about for tooth enamel. 相似文献
104.
Siddiquee S Cheong BE Taslima K Kausar H Hasan MM 《Journal of chromatographic science》2012,50(4):358-367
A simple, fast, repeatable and less laborious sample preparation protocol was developed and applied for the analysis of biocontrol fungus Trichoderma harzianum strain FA1132 by using gas chromatography-mass spectrometry. The match factors for sample spectra with respect to the mass spectra library of fungal volatile compounds were determined and used to study the complex hydrocarbons and other volatile compounds, which were separated by using different capillary columns with nonpolar, medium polar and high polar stationary phases. To date, more than 278 volatile compounds (with spectral match factor at least 90%) such as normal saturated hydrocarbons (C7-C30), cyclohexane, cyclopentane, fatty acids, alcohols, esters, sulfur-containing compounds, simple pyrane and benzene derivatives have been identified. Most of these compounds have not previously been reported. The method described in this paper is a more convenient research tool for the detection of volatile compounds from the cultures of T. harzianum. 相似文献
105.
Kazi Zakir Hossain Cristina T. Camagong Takaharu Honjo 《Analytical and bioanalytical chemistry》2001,369(6):543-545
A new method for the quantitative extraction and determination of trace amounts of iridium from hydrochloric acid media has been established based on the formation of an ion-association complex of iridium hexachloro anion IrCl6 2– with dicyclohexyl-18-crown-6 (DC18C6) oxonium cation in chloroform, then determination by inductively coupled plasma atomic emission spectrometry (ICP–AES). The effect of various factors (solvent, acid concentration, crown ether, reagent concentration, shaking time, composition of the extracted species, foreign ions, etc.) on the extraction and back-extraction of iridium has been investigated. The procedure was used to determine traces of iridium in palladium chloride and rhodium chloride. 相似文献
106.
A. H. Mahmoudi S. Hossain C. E. Truman D. J. Smith M. J. Pavier 《Experimental Mechanics》2009,49(4):595-604
Mechanical strain relief techniques for estimating the magnitude of residual stress work by measuring strains or displacements
when part of the component is machined away. The underlying assumption is that such strain or displacement changes result
from elastic unloading. Unfortunately, in components containing high levels of residual stress, elastic-plastic unloading
may well occur, particularly when the residual stresses are highly triaxial. This paper examines the performance of one mechanical
strain relief technique particularly suitable for large section components, the deep hole drilling (DHD) technique. The magnitude
of error is calculated for different magnitudes of residual stress and can be substantial for residual stress states close
to yield. A modification to the technique is described to allow large magnitudes of residual stress to be measured correctly.
The new technique is validated using the case of a quenched cylinder where use of the standard DHD technique leads to unacceptable
error. The measured residual stresses using the new technique are compared with the results obtained using the neutron diffraction
technique and are shown to be in excellent agreement. 相似文献
107.
Hossain MJ Yamasaki M Mikuriya M Kuribayashi A Sakiyama H 《Inorganic chemistry》2002,41(15):4058-4062
A new end-off type acyclic ligand with four hydroxyethyl arms, 2,6-bis[bis(2-hydroxyethyl)aminomethyl]-4-methylphenol [H(bhmp)], formed dinuclear cobalt(II) complexes [Co(2)(bhmp)(OAc)(2)]BPh(4) (1) and [Co(2)(bhmp)(OBz)(2)]BPh(4) (2). The complex 1.2.5CH(3)CN (C(50)H(62.5)BCo(2)N(4.5)O(9)) crystallizes in the monoclinic space group C2/c with dimensions a = 25.424(5) A, b = 13.376(2) A, c = 29.913(6) A, beta = 105.930(3) degrees, and V = 9781(3) A(3) and with Z = 8. X-ray diffraction analysis revealed a mu-phenoxo-bis(mu-acetato)dicobalt(II) core structure containing two octahedral cobalt(II) ions. Electronic spectra were investigated for 1 and 2 in the range 400-1800 nm, and the data were typical for the octahedral high-spin cobalt(II) complexes. Magnetic susceptibility was measured for 1 and 2 over the temperature range 4.5-300 K, and the data were analyzed well using our theoretical method. The best fitting parameters were kappa = 0.77, lambda = -116 cm(-1), Delta = 572 cm(-1), and J = -0.44 cm(-1) for complex 1 and kappa = 0.96, lambda = -93 cm(-1), Delta = 616 cm(-1), and J = -0.33 cm(-1) for complex 2. 相似文献
108.
109.
T. Ishii M. Asai A. Makishima I. Hossain P. Kleinheinz M. Ogawa M. Matsuda S. Ichikawa 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):15-19
Nuclei in the neutron-rich Ni region have been studied by γ-ray spectroscopy. Gamma-rays emitted from isomers, with T
1/2 > 1 ns, produced in heavy-ion deep-inelastic collisions were measured with an isomer-scope. The nuclear structure of the
doubly magic 68Ni and its neighbor 69,71Cu is discussed on the basis of the shell model. Future experiments for more neutron-rich Ni nuclei are also viewed.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
110.
Ali Mohammad Akbar Edwards Alice A. Tuah Jauyah Hossain Mir Ezharul Nazimuddin Mohamed 《Transition Metal Chemistry》1997,23(1):41-44
A new, potentially polydentate sulfur–nitrogen chelating agent, 2,6–bis(N-methyl-S-methyldithiocarbazato)pyridine (L) has
been synthesized and characterized. With nickel(II) salts, the ligand yields complexes of empirical formula NiLX2·nH2O (X=Cl−,
NCS− or NO3−; n=0 or 1) in which it behaves as a quadridentate NSSN chelating agent, coordinating to the nickel(II) ion via
the two amino nitrogen atoms and the two sulfur atoms. Magnetic and spectral evidence support a distorted octahedral structure
for these complexes. The ligand reacts with copper(II), platinum(II) and palladium(II) salts to yield homo-binuclear complexes
of general formula [M2LX4]·nSol (M=CuII, PtII or PdII; X=Cl− or Br−; n=0.5, 1 or 2; Sol=H2O, MeOH or MeCOMe), in which each
of the metal ions is in a square-planar environment. These complexes have been characterized by a variety of physicochemical
techniques.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献