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961.
962.
A very simple model based on γ-W0 mixing (but not on spontaneously broken gauge symmetry) is shown to reproduce all the quantitative predictions of the standard (Weinberg-Salam) model as far as low-energy phenomenology is concerned. The model predicts intermediate-boson mass relations weaker than Weinberg's. Weinberg's mass formulae, however, can be accommodated in our model provided the γ-W0 mixing parameter and the coupling constants (e and g) satisfy a special relation. This relation also guarantees asymptotic SU(2) × U(1), decent high-energy behavior in processes like and the SU(2) × U(1) value for the W± boson gyromagnetic ratio. Speculative attempts are made to understand the sign and magnitude of “sin2 θW”. 相似文献
963.
Norio Ichinose Shigeyuki Yamada Nobuo Sakurai Toraya Fujiyama Naoko Masuda 《Fresenius' Journal of Analytical Chemistry》1978,293(1):23-24
Summary A new type of separation of phosphate ion, along with its spectrophotometric determination, was established by liquid-liquid extraction, where the yellow heteropoly acid formed by the reaction with ammonium molybdate in acid solution is quantitatively extracted into molten benzophenone at a temperature of about 60° C. When cooled down to room temperature, the benzophenone extract converts from the liquid state to the solid state. The resulting solidified extract is dissolved in methyl propionate, and the phosphate ion in the solvent is determined spectrophotometrically by the blue heteropoly acid method. Possible interference by Si, As and Ge is eliminated by the separation procedure.The authors wish to thank President Dr. Yawara Yoshitoshi and Prof. Yoshisaburo Ota of University School of Medicine, for their hospitality and encouragement. 相似文献
964.
The macroionization constants and thermodynamic parameters of twelve commercial sulphonamides were determined by potentiometric titration at 15 degrees , 25 degrees and 35 degrees and by spectrophotometry at 25 degrees , in aqueous solution of ionic strength 0.1 (NaClO(4)). The microionization constants and the tautomeric constants (concentration ratios of zwitterion to uncharged or neutral species) were obtained according to the Edsall method combined with complementary tristimulus colorimetry. By utilizing the microionization constants, the species distribution as a function of pH were calculated for the three kinds of sulphonamides. 相似文献
965.
966.
967.
The azimuthal angle dependence of Sn 3d X-ray photoelectron diffraction from the Ge(111)(√3 × √3)R30°-Sn surface has been measured and analyzed kinematically. It has been found that triplets of Sn atoms, the side of the triplet being 3.1 ± 0.1 Å, are formed on the substrate surface although the bonding sites of the triplets to the substrate are yet to be determined. 相似文献
968.
A new dimension-reduction graphical method for testing high-dimensional normality is developed by using the theory of spherical distributions and the idea of principal component analysis. The dimension reduction is realized by projecting high-dimensional data onto some selected eigenvector directions. The asymptotic statistical independence of the plotting functions on the selected eigenvector directions provides the principle for the new plot. A departure from multivariate normality of the raw data could be captured by at least one plot on the selected eigenvector direction. Acceptance regions associated with the plots are provided to enhance interpretability of the plots. Monte Carlo studies and an illustrative example show that the proposed graphical method has competitive power performance and improves the existing graphical method significantly in testing high-dimensional normality. 相似文献
969.
针对织物疵点检测,将灰度共生矩阵(Gray-level Co-occurrence Matrix,GLCM)与反向投影结合起来,提出了一种基于GLCM的反向投影方法(GLCM-BP)。首先介绍了GLCM-BP的原理,然后给出了织物疵点检测流程,分析并优化了GLCM的距离d与灰度级N等参数,选择了相应的滤波与自适应阈值分割方法以检测疵点,同时给出了7种常见疵点的检测结果。最后将本文方法与GLCM方法作了检出率的比较。结果表明,提出的方法具有良好的疵点分割效果,可显著提高疵点检出率。 相似文献
970.
In recent years the class of known fluorescent proteins (FPs) has dramatically expanded as an ever-increasing numbers of variants and homologs of the green fluorescent protein (GFP) from Aequorea jellyfish have been either engineered in the lab or discovered in other marine organisms. The red fluorescent protein (RFP) from Discosoma coral (also known as dsFP583 and DsRed) has proven to be a particularly fruitful progenitor of variants with biochemical and spectroscopic properties conducive to applications in live cell imaging. We have investigated the tolerance of an engineered monomeric descendent of Discosoma RFP, known as mCherry, towards peptide insertion and circular permutation. Starting from a random library of insertion variants, we identified six genetically distinct sites localized in three different loops where a sequence of five residues could be inserted without abolishing the ability of the protein to form its intrinsic red fluorescent chromophore. For each of these insertion variants, a corresponding circular permutation variant was created in which the original N- and C-termini were connected by a six-residue linker and new termini were introduced at the site of the insertion. All six circular permutation variants had significantly diminished brightness relative to the analogous insertion variants. The most promising circular permutation variant has termini at the position corresponding to residue 184 of mCherry and retains 37% of the intrinsic fluorescent brightness of mCherry. These circularly permuted variants may serve as the foundation for construction of genetically encoded Ca2+ sensors analogous to the previously reported camgaroo, pericam and G-CaMP sensors based on variants of Aequorea GFP. 相似文献