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991.
Ohshima N Koyama T Tanigawa H Kotsugi M Ohkouchi T Chiba D Kinoshita T Ono T 《J Phys Condens Matter》2011,23(38):382202
Current-induced magnetic domain wall (DW) displacement in a Co/Ni nano-wire with perpendicular magnetic anisotropy was investigated in real space by photoemission electron microscopy (PEEM) for the first time. DW velocity determined from the PEEM observation was 40?m?s(-1) for the current density of 2.5?×?10(12)?A?m(-2), which was consistent with the result obtained by the electrical measurement used in our previous reports. 相似文献
992.
Teruaki Toyota Tadashi Hanafusa Takashi Oda Iwane Koumura Takanori Sasaki Eiji Matsuura Hiromi Kumon Tsuneo Yano Toshiro Ono 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):295-300
Ion exchange is a simple and efficient method for separating no-carrier-added 64Cu from an irradiated Ni target. We developed a semi-automated two-round 64Cu separation system equipped with a strong-base anion exchange resin column. We first verified the efficiency of the system using a non-radioactive substitute consisting of 25 mg of Ni and 127 ng of Cu, and confirmed that Cu was completely eluted at the second round of the separation step. After the bombardment, separation of 64Cu from the Ni target was achieved with high radiochemical purity. 64Cu produced and separated in this study had an extremely low level of Ni impurity. It could be used for labeling monoclonal antibodies for antibody positron emission tomography imaging and synthesizing radiopharmaceuticals. 相似文献
993.
Dr. Jakub Šebera Prof. Jaroslav Burda Dr. Michal Straka Prof. Akira Ono Prof. Chojiro Kojima Prof. Yoshiyuki Tanaka Dr. Vladimír Sychrovský 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(30):9884-9894
A reaction mechanism that describes the substitution of two imino protons in a thymine:thymine (T:T) mismatched DNA base pair with a HgII ion, which results in the formation of a (T)N3‐HgII‐N3(T) metal‐mediated base pair was proposed and calculated. The mechanism assumes two key steps: The formation of the first HgII? N3(T) bond is triggered by deprotonation of the imino N3 atom in thymine with a hydroxo ligand on the HgII ion. The formation of the second HgII? N3(T) bond proceeds through water‐assisted tautomerization of the remaining, metal‐nonbonded thymine base or through thymine deprotonation with a hydroxo ligand of the HgII ion already coordinated to the thymine base. The thermodynamic parameters ΔGR=?9.5 kcal mol?1, ΔHR=?4.7 kcal mol?1, and ΔSR=16.0 cal mol?1 K?1 calculated with the ONIOM (B3LYP:BP86) method for the reaction agreed well with the isothermal titration calorimetric (ITC) measurements by Torigoe et al. [H. Torigoe, A. Ono, T. Kozasa, Chem. Eur. J. 2010 , 16, 13218–13225]. The peculiar positive reaction entropy measured previously was due to both dehydration of the metal and the change in chemical bonding. The mercury reactant in the theoretical model contained one hydroxo ligand in accord with the experimental pKa value of 3.6 known for an aqua ligand of a HgII center. The chemical modification of T:T mismatched to the T‐HgII‐T metal‐mediated base pair was modeled for the middle base pair within a trinucleotide B‐DNA duplex, which ensured complete dehydration of the HgII ion during the reaction. 相似文献
994.
Single nucleotide polymorphisms (SNPs) are base differences in the human genome. These differences are favorable markers for
genetic factors including those associated with risks of complex diseases and individual responses to drugs. When two duplex
DNAs with different types of SNPs are mixed and reannealed, the two novel heteroduplexes containing mismatched base pairs
are formed in addition to the two initial perfectly matched homoduplexes. Heteroduplex analysis recognizing the newly formed
mismatched base pairs is useful for SNP detection. Various strategies to detect the mismatched base pairs were devised due
to the potential applications of SNPs. However, they were not always convenient and accurate. Here, we propose a novel strategy
to detect the mismatched base pairs by the specific interaction between the Hg2+ ion and a T:T mismatched base pair and that between the Ag+ ion and a C:C mismatched base pair. UV melting indicated that the melting temperature of only the heteroduplexes with the
T:T and C:C mismatched base pair specifically increased on adding the Hg2+ and Ag+ ion, respectively. Fluorescence resonance energy transfer analyses indicated that the intensity of fluorophore emission of
only the fluorophore and quencher-labeled heteroduplexes with the T:T and C:C mismatched base pair specifically decreased
on adding the Hg2+ and Ag+ ion, respectively. We propose that the addition of the metal ion could be a convenient and accurate strategy to detect the
mismatched base pair in the heteroduplex. This novel strategy might make the heteroduplex analysis easy and eventually lead
to better SNP detection. 相似文献
995.
N. Momoshima F. Inoue T. Ohta Y. Mahara J. Shimada R. Ikawa M. Kagabu M. Ono K. Yamaguchi S. Sugihara M. Taniguchi 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):761-767
Groundwater age was determined by 85Kr/Kr specific activity of gases dissolved in groundwater at Kumamoto Area, in which newly developed Kr extraction system and liquid scintillation counting technique for 85Kr were applied. Apparent mean residence times observed were 8.2 ± 0.7 years and 20.7 ± 0.6 years for the groundwater taken from a well at the recharge area and that from an artesian borehole at the discharge area, respectively showing a consistent age trend estimated from the observed groundwater flow system of Kumamoto Area and also that determined using environmental tritium. Similar mean residence times of 85Kr and tritium were observed at the discharge area but the mean residence time of 85Kr at the recharge area was younger compared to that of tritium, probably due to mixing of river water containing recent 85Kr high in concentration into groundwater flow coming from the northern upland??s recharge area. The mean residence time of the groundwater flow coming from northern upland area and a traveling time of the groundwater between two sampling points were estimated by a simple model assuming mixing the river water with the groundwater and a piston flow between two sampling points. 相似文献
996.
In [11] it was proved that, given a compact toric Sasaki manifold with positive basic first Chern class and trivial first
Chern class of the contact bundle, one can find a deformed Sasaki structure on which a Sasaki-Einstein metric exists. In the
present paper we first prove the uniqueness of such Einstein metrics on compact toric Sasaki manifolds modulo the action of
the identity component of the automorphism group for the transverse holomorphic structure, and secondly remark that the result
of [11] implies the existence of compatible Einstein metrics on all compact Sasaki manifolds obtained from the toric diagrams
with any height, or equivalently on all compact toric Sasaki manifolds whose cones have flat canonical bundle. We further
show that there exists an infinite family of inequivalent toric Sasaki-Einstein metrics on for each positive integer k. 相似文献
997.
R. Yasuhara H. Kumigashira M. Oshima F. Guo T. Kinoshita K. Ono K. Ikeda Z. Liu 《Applied Surface Science》2008,254(15):4757-4761
We have applied the spectroscopic photoemission and low energy electron microscope to study high-k gate dielectrics and have performed the following in situ operations during ultrahigh vacuum annealing: real-time observation of surface morphology and microregion photoelectron spectroscopy measurements. Changes in surface morphology and electronic states were consistent with the models previously reported in the case of HfO2/Si. No clear differences between void regions and nonvoid regions have been observed in microregion photoelectron spectra for poly-Si/HfO2/Si, regardless of phase separation in real space. These results have suggested that the initial void formation occurs in about 100-nm wide regions for both HfO2/Si and poly-Si/HfO2/Si. 相似文献
998.
999.
Kosuke Ono 《Mathematical Methods in the Applied Sciences》1997,20(2):151-177
We study on the initial-boundary value problem for some degenerate non-linear wave equations of Kirchhoff type with a strong dissipation: When the initial energy $E(u_0,u_1)\equiv \left\| u_1\right\| ⁁2+\frac 1{\gamma +1}\left\| \nabla u_0\right\| ⁁{2(\gamma +1)}-\frac 2{\alpha +2}\left\| u_0\right\| _{\alpha +2}⁁{\alpha +2}$ associated with the equations is non-negative and small, a unique (weak) solution exists globally in time and has some decay properties. When the initial energy E(u0,u1) is negative, the solution blows up at some finite time. In the proof we use the ‘modified potential well’ and ‘Concavity’ methods. © 1997 by B.G. Teubner Stuttgart-John Wiley & Sons, Ltd. 相似文献
1000.
Takashi Iizawa Haruo Ono Kouji Okatome 《Journal of polymer science. Part A, Polymer chemistry》1996,34(12):2407-2414
Soluble polymeric phase transfer catalysts (PTCs) containing benzyltributylphosphonium chloride moieties and polar N,N-dialkyl-acrylamide with long alkyl groups such as N,N-dipropylacrylamide, N,N-dibutylacrylamide, N,N-dihexylacrylamide, and N,N-dioctylacrylamide were prepared via two-step reactions from p-chloromethylstyrene and the corresponding N,N-dialkylacrylamide. When the obtained polymers were added, the phase transfer catalyzed reaction of benzylchloride with solid potassium acetate to proceed smoothly. The catalytic activity was strongly affected by the content of phosphonium chloride and the varieties of comonomer unit in the polymeric PTC. The polymeric PTC containing the N,N-dihexylacrylamide unit showed excellent high catalytic activity in a low polar solvent such as the mixed solvent of toluene with 70 vol % n-tridecane. Therefore, the polymer containing lipophilic long chains such as the hexyl group is desirable for polymeric PTC. © 1996 John Wiley & Sons, Inc. 相似文献