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991.
Video-Assisted Rigid Endoscopic Laryngosurgery: Application to Cases with Difficult Laryngeal Exposure 总被引:8,自引:0,他引:8
In some cases of microlaryngosurgery, laryngeal exposure with a direct laryngoscope is difficult because of a variety of reasons. In such cases, we now use a long rigid endoscope inserted into the side tube of the direct laryngoscope together with a video system. The lesion can be removed while the phonosurgeon observes the magnified images of the larynx on the video monitor. We describe the surgical procedure together with the preoperative and postoperative evaluation of vocal function in 13 patients with benign laryngeal lesions. A good surgical and vocal outcome was achieved in all cases. The method appeared to be useful for treating dysphonia in patients in whom it was difficult to expose the larynx with a direct laryngoscope. 相似文献
992.
Yasuhiro Isogai Anna Ishii Manabu Ishida Masahiro Mukai Motonori Ota Ken Nishikawa Tetsutaro Iizuka 《Journal of Chemical Sciences》2000,112(3):215-221
De novo design of artificial proteins is an essential approach to elucidate the principles of protein architecture and to understand
specific functions of natural proteins and also to yield novel molecules for medical and industrial aims. We have designed
artificial sequences of 153 amino acids to fit the main-chain framework of the sperm whale myoglobin structure based on the
knowledge-based energy functions to evaluate the compatibility between protein tertiary structures and amino acid sequences.
The synthesized artificial globins bind a single heme per protein molecule as designed, which show well-defined electrochemical
and spectroscopic features characteristic of proteins with a low-spin heme. Redox and ligand binding reactions of the artificial
heme proteins were investigated and these heme-related functions were found to vary with their structural uniqueness. Relationships
between the structural and functional properties are discussed. 相似文献
993.
Daisuke Yamano Masahiro Kawasaki Agnes Perrin 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(1):45-10728
We present the high resolution absorption measurements of gaseous HONO at room temperature using continuous-wave cavity ring-down spectroscopy in the near-infrared region between 6017 and 6067 cm−1 at a resolution of 1 pm (0.037 cm−1). For the trans-HONO isomer an extensive analysis of the ν1+2ν3 combination band 6045.8089 cm-1 was performed starting from the results of a previous study for the 11 and 31 vibrational states [Guilmot J-M, Godefroid M, Herman M. Rovibrational parameters for trans-nitrous acid. J Mol Spectrosc 1993;160:387-400]. The present combination band is perturbed because of the existence of several dark states of HONO which could not be identified unambiguously. The rotational constants achieved for the 1132 state deviate slightly from the values which are predicted from the rotational constants achieved in the previous studies for the 11 and 31 vibrational states of trans-HONO. 相似文献
994.
A study of travel time prediction using universal kriging 总被引:1,自引:0,他引:1
Hidetoshi Miura 《TOP》2010,18(1):257-270
This study describes an approach for predicting travel time by kriging. The kriging method, which is a means of spatial prediction,
is used as prediction measure for car travel time in an imaginary four-dimensional space. Each point in the space represents
a single journey: the coordinates of a point are the coordinates of the origin and destination on a plane. The travel time
can then be viewed as a function over this four-dimensional space. The prediction relies on the feature that nearby points
(in the four-dimensional space) will have almost the same travel time. In this approach, it is not necessary to break down
travel times from origin to destination into link travel times. The approach will also allow us to use information from “probe
vehicles” for travel time prediction in the near future. The feasibility of this approach is demonstrated through a case study
in London and its environs. The case study uses 200 observations for verification. The multiple correlation coefficient of
estimated travel time and the verification data is 0.9045. The results indicate that 95% prediction limits are between ±10
minutes and ±30 minutes for travel between two arbitrary points. This prediction method is effective for urban districts with
links having changeable travel time owing to congestion. 相似文献
995.
E.S.R. spectra of PF4 radicals were investigated with single crystals of PF3 made at a low temperature and irradiated with γ-rays. The angular dependence of the spectral lines was satisfactorily analysed in terms of the second-order equations for large couplings of one 31P nucleus and two magnetically equivalent 19F nuclei and of the first-order equation for two 19F nuclei with small couplings. We conclude that the two magnetically equivalent fluorine nuclei occupy the axial positions of the trigonal bipyramidal structure of the PF4 radical and the other two fluorine nuclei are in the equatorial positions. Furthermore, the unpaired electron of the PF4 radical was shown to occupy an orbital consisting mainly of the 2p orbital of each of the two axial fluorine atoms along the F-P-F axis and the 3s and 3p orbitals, directed towards the vacant equatorial position of the central phosphorus atom. The orbital of the unpaired electron can be reasonably represented as a Rundle three-centre non-bonding orbital. The results obtained for the PF4 radicals not only strongly support the results given for POCl3 - radicals, but also allow us to discuss the electronic structure of phosphoranyl radicals in more detail. 相似文献
996.
Dr. Masahiro Yamashina Sho Matsuno Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14147-14150
The methyl group is a small substituent, usually showing relatively weak or no interactions with other functional groups and metal ions. Herein, we present the recognition of the number of methyl groups on synthetic and natural aromatic compounds (i.e., benzene and xanthine derivatives, respectively) by the 1 nm‐sized polyaromatic cavity of a coordination capsule in water. Detailed competitive encapsulation experiments as well as X‐ray crystallographic analysis revealed that multiple guest–host CH3–polyaromatic interactions in the confined nanospace are key driving forces for the high selectivity. 相似文献
997.
998.
Anisotropic Expansion of an M2L4 Coordination Capsule: Host Capability and Frame Rearrangement 下载免费PDF全文
Masahiro Yamashina Tsubasa Yuki Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4200-4204
Anisotropic expansion of a spherical M2L4 coordination capsule through the elongation of the ligand led to a new M2L′4 capsule. The expanded capsule provides an elliptical cavity encircled by polyaromatic frameworks with large openings and thereby can encapsulate elliptical fullerene C70 and monofunctionalized fullerene C60 in high yields. In addition, selective formation of a new M2L2L′2 capsule occurs by mixing the original M2L4 and expanded M2L′4 capsules in a 1:1 ratio upon addition of C60 or monofunctionalized C60 as a template molecule. 相似文献
999.
1000.
Using scattered radiation as useful information to improve radioisotope image quality is a topic attracting many researchers. Some reports showed that incorporating scattered components offers a possibility to improve image quality. The general method is modeling scatter in multiple energy windows and incorporating that information into the reconstruction process. However, what the performance will be and how noise will behave when using scattered radiation in reconstruction are not yet well answered. In this paper, we investigate a method of modeling scatter in multiple energy windows in cases of a few projection views. The system performance is analyzed using singular value decomposition and resolution kernels. For noise behavior investigation, reconstructions are accomplished by estimating the variance of reconstructed voxel values and the effectiveness of using scatter is evaluated by resolution kernel analysis. The results show there are improvements in normalized mean-square error of the images and the resolution kernels. When photon counts fall below about one million, it is still effective to use scatter for some cases of a few projections 相似文献