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971.
Takashi Kojima Hitoshi Tsunashima Tomoki Shiozawa Hiroki Takada Takuji Sakai 《Optical and Quantum Electronics》2005,37(13-15):1319-1338
This paper describes development of a train simulator for human factors, and application of functional near-infrared spectroscopy (fNIRS) to estimation of drivers’ brain activities during train operation. One of the characteristics of train operation is that the driving tasks tend to be more monotonous than automobile driving. Therefore, train drivers are more strongly urged to avoid human errors. In order to avoid human errors in train operation, it is considered that driving support systems or the like should be developed in consideration of human properties. In developing such systems, it is necessary to identify the relation between train operation and brain activity of the driver. A train simulator designed to evaluate the human factors was developed and cerebral blood flow during train operation was measured using fNIRS. The experiment confirms the difference in drivers’ brain activities between manual and automatic operations. The results suggest that fNIRS can observe brain activation caused by train operation 相似文献
972.
In the case of iron mixed-valence complexes whose spin states are situated in the spin-crossover region, conjugated phenomena coupled with spin and charge are expected. In general, the Fe site coordinated by six S atoms is in the low-spin state, while the Fe site coordinated by six O atoms is in the high-spin state. From this viewpoint, we have synthesized and investigated physical properties for an monothiooxalato-bridged (mto = C2O3S) iron mixed-valence complex, (n-C4H9)4N[FeIIFeIII(mto)3], consisting of FeIIIO3S3 and FeIIO6 octahedra, which behaves as a ferrimagnet with its magnetic transition temperature of TN = 38 K and Weiss temperature of θ = ?93 K. From the analysis of 57Fe Mössbauer spectra of 57Fe enriched complexes, (n-C4H9)4N[57FeIIFeIII(mto)3] and (n-C4H9)4N[FeII57FeIII(mto)3], the charge transfer between FeII and FeIII exists in the paramagnetic phase. Considering the time window of 57Fe Mössbauer spectroscopy, the time scale of the valence fluctuation is at least slower than 10?7 s. In order to confirm the valence fluctuation between FeII and FeIII, we investigated the dielectric constant and found an anomalous enhancement attributed to the Fe valence fluctuation between 170 and 250 K. 相似文献
973.
We show that SDP (semidefinite programming) and SOCP (second order cone programming) relaxations provide exact optimal solutions for a class of nonconvex quadratic optimization problems. It is a generalization of the results by S. Zhang for a subclass of quadratic maximization problems that have nonnegative off-diagonal coefficient matrices of quadratic objective functions and diagonal coefficient matrices of quadratic constraint functions. A new SOCP relaxation is proposed for the class of nonconvex quadratic optimization problems by extracting valid quadratic inequalities for positive semidefinite cones. Its effectiveness to obtain optimal values is shown to be the same as the SDP relaxation theoretically. Numerical results are presented to demonstrate that the SOCP relaxation is much more efficient than the SDP relaxation. 相似文献
974.
975.
Teruaki Sakurai Masayuki Ochiai Chikara Kojima Takami Ohta Kitao Fujiwara 《应用有机金属化学》2005,19(2):226-230
In this study, we observed the first in vivo acute immunotoxicity of a trimethyl(2‐hydroxyethyl)arsonium cation, namely arsenocholine (AsCho), which is present in marine animals that are ingested daily as seafood in many countries. It has been reported that AsCho has significant acute in vivo toxicity. A high dose of the synthetic pure AsCho was administered to CDF1 mice intraperitoneally (0.1 g kg?1 mouse weight) or orally (a total of 10.0 g kg?1 mouse weight); its effect on the immune organs and immune effector cells was assessed. Administered AsCho, especially via the oral route, showed weak and partial, but significant, in vivo immunotoxicity in mice, although it did not cause any severe acute inflammatory responses. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
976.
The bandwidth B(G) of a graph G is the minimum of the quantity max{|f(x)−f(y)| : xyE(G)} taken over all proper numberings f of G. The composition of two graphs G and H, written as G[H], is the graph with vertex set V(G)×V(H) and with (u1,v1) is adjacent to (u2,v2) if either u1 is adjacent to u2 in G or u1=u2 and v1 is adjacent to v2 in H. In this paper, we investigate the bandwidth of the composition of two graphs. Let G be a connected graph. We denote the diameter of G by D(G). For two distinct vertices x,yV(G), we define wG(x,y) as the maximum number of internally vertex-disjoint (x,y)-paths whose lengths are the distance between x and y. We define w(G) as the minimum of wG(x,y) over all pairs of vertices x,y of G with the distance between x and y is equal to D(G). Let G be a non-complete connected graph and let H be any graph. Among other results, we prove that if |V(G)|=B(G)D(G)−w(G)+2, then B(G[H])=(B(G)+1)|V(H)|−1. Moreover, we show that this result determines the bandwidth of the composition of some classes of graphs composed with any graph. 相似文献
977.
Yoshihiro Shimoyama Dr. Tomoya Ishizuka Dr. Hiroaki Kotani Prof. Dr. Yoshihito Shiota Prof. Dr. Kazunari Yoshizawa Dr. Kaoru Mieda Prof. Dr. Takashi Ogura Dr. Toshihiro Okajima Prof. Dr. Shunsuke Nozawa Prof. Dr. Takahiko Kojima 《Angewandte Chemie (International ed. in English)》2016,55(45):14041-14045
Proton‐coupled electron‐transfer oxidation of a RuII?OH2 complex, having an N‐heterocyclic carbene ligand, gives a RuIII?O. species, which has an electronically equivalent structure of the RuIV=O species, in an acidic aqueous solution. The RuIII?O. complex was characterized by spectroscopic methods and DFT calculations. The oxidation state of the Ru center was shown to be close to +3; the Ru?O bond showed a lower‐energy Raman scattering at 732 cm?1 and the Ru?O bond length was estimated to be 1.77(1) Å. The RuIII?O. complex exhibits high reactivity in substrate oxidation under catalytic conditions; particularly, benzaldehyde and the derivatives are oxidized to the corresponding benzoic acid through C?H abstraction from the formyl group by the RuIII?O. complex bearing a strong radical character as the active species. 相似文献
978.
Ligand‐Controlled Synthesis of [3]‐ and [4]Cyclo‐9,9‐dimethyl‐2,7‐fluorenes through Triangle‐ and Square‐Shaped Platinum Intermediates 下载免费PDF全文
Dr. Eiichi Kayahara Rui Qu Mitsuru Kojima Dr. Takahiro Iwamoto Prof. Dr. Toshiyasu Suzuki Prof. Dr. Shigeru Yamago 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(52):18939-18943
The syntheses of [3]‐ and [4]cyclo‐9,9‐dimethyl‐2,7‐fluorenes ([3] and [4]CFRs), cyclic trimer, and tetramers of 9,9‐dimethyl‐2,7‐fluorene (FR), respectively, were achieved by the platinum‐mediated assembly of FR units and subsequent reductive elimination of platinum. A triangle‐shaped tris‐platinum complex and a square‐shaped tetra‐platinum complex were obtained by changing the platinum ligand. The structure of the triangle complex was unambiguously determined by X‐ray crystallographic analysis. Reductive elimination of each complex gave [3] and [4]CFRs. Two rotamers of [3]CFR were sufficiently stable at room temperature and were separated by chromatography. The physical properties of the CFRs were also investigated theoretically and experimentally. 相似文献
979.
Dynamic Chirality Control of tropos DPCB‐digold Skeleton by Chiral Binaphthyldicarboxylate 下载免费PDF全文
Prof. Dr. Shigekazu Ito Masaki Nanko Tomokazu Shinozaki Masafumi Kojima Dr. Kohsuke Aikawa Prof. Dr. Koichi Mikami 《化学:亚洲杂志》2016,11(6):823-827
The planar 3,4‐diphosphinidenecyclobutene (DPCB) can be remarkably twisted into a C2‐type helical structure by dual coordination of a AuCl moiety. A prompt chirality control of the twisted DPCB skeleton ligated by the digold units affords the enantiopure structure by exchanging the chloride ligands for chiral [1,1′‐binaphthalene]‐2,2′‐dicarboxylate. The chirality of the diaurated 2,2′‐bis(diphenylphosphanyl)‐1,1′‐biphenyl (BIPHEP) system can be controlled prior to that of DPCB. Mixing of a DPCB‐bis(chlorogold) complex with the chiral silver salt dynamically leads to a single diastereomer, which was characterized by the 31P NMR spectrum and the CD couplet patterns in the visible (DPCB) area. The absolute configuration of the singly induced helical structure was assigned by the theoretical CD spectra determined by TD‐DFT calculations. Intramolecular alkoxycyclization of hexa‐4,5‐dien‐1‐ol catalyzed by the asymmetric DPCB‐digold structure were also attempted. 相似文献
980.
Yusuke Hashimoto Tatsuya Mori Seiji Kojima 《Molecular Crystals and Liquid Crystals》2016,629(1):258-263
The low-energy vibrational properties of polymethyl methacrylate (PMMA) were studied by terahertz time-domain spectroscopy and Raman scattering. The real and imaginary parts of a complex dielectric constant were accurately determined in the frequency range from 0.2 to 5.0 THz. The imaginary part of the dielectric constant shows a line-shape similar to the imaginary part of the Raman susceptibility measured by Raman scattering. These two spectra show broad peaks at about 2.3 THz. We also separately determined the Raman and far-infrared light-vibration coupling constants of the PMMA using the vibrational density of states determined by cold neutron inelastic scattering in the literature. 相似文献