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53.
Juan M. Salas Abderrahman Rahmani Marìa A. Romero Miguel Quiròs Edward R. T. Tiekink 《Journal of chemical crystallography》1994,24(10):669-673
The crystal and molecular structure of the title compound, ·[Pd(S=C(NH2)2)4]Cl2·2dmtp·2H2O. has been determined and refined to a finalR=0.034. The cation is centrosymmetric with the Pd atom existing in a square planar geometry with two disparate Pd–S bond distances of 2.3129(9) and 2.292(1)Å. Interatomic parameters are reported for the first non-coordinated dmtp molecule; these suggest the predominance of a particular canonical form in the solid state. The lattice is stabilized via a series H-bonding contacts involving the thiourea. Cl– and dmtp species. Crystals of [Pd(S=C(NH2)2)4]Cl2 · 2dmtp · 2H2O are monoclinic with space groupP21/c, and unit cell dimensionsa=15.129(1),b=8.512(1),c=12.663(1) Å, =104.05(1)°. 相似文献
54.
Jonas Volmer S. Hamidreza Arabi Christian Henning Marcus A. Glomb Dariush Hinderberger 《Macromolecular bioscience》2023,23(3):2200487
The changes of technological properties of albumin-based hydrogels induced by increasing degrees of post-translational modification of the protein are reported. Maillard-type modification of amino acids arginine and lysine of albumin is achieved through glyoxal as an α-dicarbonyl compound. The degrees of modification are fine-tuned using different molar ratios of glyoxal. Hydrogels are thermally induced by heating highly concentrated precursor solutions above the protein's denaturation temperature. While the post-translational modifications are determined and quantified with mass spectrometry, continuous-wave (CW) electron paramagnetic resonance (EPR) spectroscopy shed light on the protein fatty acid binding capacity and changes thereof in solution and in the gel state. The viscoelastic behavior is characterized as a measure of the physical strength of the hydrogels. On the nanoscopic level, the modified albumins in low concentration solution reveal lower binding capacities with increasing degrees of modification. On the contrary, in the gel state, the binding capacity remains constant at all degrees of modifications. This indicates that the loss of fatty acid binding capacity for individual albumin molecules is partially compensated by new binding sites in the gel state, potentially formed by modified amino acids. Such, albumin glycation offers a fine-tuning method of technological and nanoscopic properties of these gels. 相似文献
55.
Hassan Keypour Reza Azadbakht Hadi Amiri Rudbari Alireza Heydarinekoo Hamidreza Khavasi 《Transition Metal Chemistry》2009,34(8):835-839
Three new potentially hexadentate N4O2 Schiff-base ligands (H2L1, H2L2 and H2L3) were prepared from the reaction of the polyamines N,N′-bis(2-aminophenyl)-1,2-ethanediamine (L1), N,N′-bis(2-aminophenyl)-1,3-propanediamine (L2) and N,N′-bis(2-aminophenyl)-1,4-butanediamine (L3), respectively with salicylaldehyde. Reaction of the Schiff bases with Ni(II) salts in the presence of N(Et)3 gave the neutral complexes [NiL4], [NiL5] and [NiL6]. Ni(II) complexes of the polyamines were also prepared. One of complexes [Ni(L1)(MeCN)2](ClO4)2·MeCN has been characterized through X-ray diffraction methods. 相似文献
56.
This paper presents a multiobjective evolutionary algorithm (MOEA) capable of handling stochastic objective functions. We
extend a previously developed approach to solve multiple objective optimization problems in deterministic environments by
incorporating a stochastic nondomination-based solution ranking procedure. In this study, concepts of stochastic dominance
and significant dominance are introduced in order to better discriminate among competing solutions. The MOEA is applied to
a number of published test problems to assess its robustness and to evaluate its performance relative to NSGA-II. Moreover,
a new stopping criterion is proposed, which is based on the convergence velocity of any MOEA to the true Pareto optimal front,
even if the exact location of the true front is unknown. This stopping criterion is especially useful in real-world problems,
where finding an appropriate point to terminate the search is crucial. 相似文献
57.
Hamidreza?SalimiEmail author Karl-Heinz?Wolf Johannes?Bruining 《Transport in Porous Media》2012,91(2):391-422
This article deals with developing a solution approach, called the non-isothermal negative saturation (NegSat) solution approach.
The NegSat solution approach solves efficiently any non-isothermal compositional flow problem that involves phase disappearance,
phase appearance, and phase transition. The advantage of the solution approach is that it circumvents using different equations
for single-phase and two-phase regions and the ensuing unstable procedure. This paper shows that the NegSat solution approach
can also be used for non-isothermal systems. The NegSat solution approach can be implemented efficiently in numerical simulators
to tackle modeling issues for mixed CO2–water injection in geothermal reservoirs, thermal recovery processes, and for multicontact miscible and immiscible gas injection
in oil reservoirs. We illustrate the approach by way of example to cold mixed CO2–water injection in a 1D geothermal reservoir. The solution is compared with an analytical solution obtained with the wave-curve
method (method of characteristics) and shows excellent agreement. A complete set of simulations is carried out, which identifies
six bifurcations. The two main bifurcations are (1) when the most downstream compositional wave is replaced by a compositional
shock and (2) when an extra Buckley–Leverett rarefaction appears. The plot of the useful energy (exergy) versus the CO2 storage capacity shows a Z-shape. The top horizontal part represents a branch of high exergy recovery/relatively lower storage capacity, whereas the
bottom part represents a branch of lower exergy recovery/higher storage capacity. 相似文献
58.
Amin Heshmati-Moulai Hamidreza Simchi Mahdi Esmaeilzadeh 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(7):128
We study perfect valley polarization in a molybdenum disulfide (MoS2) nanoribbon monolayer using two bands Hamiltonian model and non-equilibrium Green’s function method. The device consists of a one-dimensional quantum wire of MoS2 monolayer sandwiched between two zigzag MoS2 nanoribbons such that the sites A and B of the honeycomb lattice are constructed by the molecular orbital of Mo atoms, only. Spin-valley coupling is seen in energy dispersion curve due to the inversion asymmetry and time-reversal symmetry. Although, the time reversal symmetry is broken by applying an external magnetic field, the valley polarization is very small. A valley polarization equal to 46% can be achieved using an exchange field of 0.13 eV. It is shown that a particular spin-valley combination with perfect valley polarization can be selected based on a given set of exchange field and gate voltage as input parameters. Therefore, the valley polarization can be detected by detecting the spin degree of freedom. 相似文献
59.
Hamidreza Shirvani-Mahdavi Seyede Zahra Shoursheini Hamid Gholami Ziba Dini-Torkamani Sare Ghahari-Korani 《Applied physics. B, Lasers and optics》2014,117(3):823-832
Identification and concentration measurement of constituent elements of a metallic alloy is demonstrated by calibration-free laser-induced breakdown spectroscopy (CF-LIBS) according to a special peak intensity-based model and considering the self-absorption effect. In this procedure, which is based on the line pair ratio method, the effect of line widths, though needs to be theoretically considered, may be approximately ignored. This is mainly true for the multiplet lines, but this property, in the case of some generic spectral lines in a measured spectrum, can be sometimes regarded. Initially, the optical penetration depth and therefrom self-absorption coefficient of each selected spectral line is calculated using the experimental (self-absorbed) intensity of the line. Then, the true (non-self-absorbed) intensity, which is basis of the conventional CF-LIBS calculation, is obtained through a recursive algorithm implemented by the MATLAB programming. In the experimental examination, the recorded spectrum reflects that the metallic alloy is consisted of gold, copper and silver. The concentration of elements is calculated with and without regarding self-absorption correction using 27 trios of spectral lines related to the elements. The average concentrations signify that the measurement error relative to the certified value for the concentration of the gold is modified from 3.56 % in the normal way to 0.34 % after applying self-absorption correction. 相似文献
60.
B. Rahmani E. Ghossein I. Villemure M. Levesque 《International Journal of Solids and Structures》2014
This paper presents an identification procedure based on the Virtual Fields Method (VFM) for identifying in situ mechanical properties of composite materials constitutive phases from 3D full-field measurements. The new procedure, called the Regularized Virtual Fields Method (RVFM), improves the accuracy of the VFM thanks to the imposition of mechanical constraints derived from an appropriate homogenization model. The developed algorithms were validated through virtual experiments on particulate composites. The robustness of both the VFM and the RVFM was assessed in the presence of noisy strain data for various microstructures. A study was also carried out to investigate the influence of the size of region of interests on the reliability of the identified parameters. Accordingly, the optimum size of region of interest was determined based on full-field measurement requirements and accuracy of the identified parameters. This study enables determining, a priori, the required magnification level of 3D images for composites of any mechanical and morphological characteristics. 相似文献