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981.
982.
983.
Orhan Kizilkaya Masaki Ono Eizi Morikawa 《Journal of Electron Spectroscopy and Related Phenomena》2006
The synchrotron-radiation-induced structural degradation in polystyrene thin films was analyzed by comparing measured ultraviolet photoemission spectroscopy (UPS) spectra with model molecular orbital calculations. The analysis confirms degradation of the phenyl pendant groups and the generation of conjugated double-bonds in the degraded polymer. The observed degradation in polystyrene is found to be very similar to one from polyethylene previously investigated. 相似文献
984.
985.
Mitsuji Yamashita Valluru Krishna ReddyLakonda Nagaprasada Rao Buchammagari HarithaMotoki Maeda Keiji SuzukiHirono Totsuka Masaki TakahashiTatsuo Oshikawa 《Tetrahedron letters》2003,44(11):2339-2341
A novel method has been developed for stereospecific conversion of 2-phospholene 1-oxides into their corresponding 2,3-epoxides in high yields using sodium peroxide as a reagent. 相似文献
986.
Fabrication of transparent and flexible carbon‐doped ZnO field emission display on plastic substrate 下载免费PDF全文
Transparent and flexible carbon doped ZnO (C:ZnO) field emission device was successfully fabricated on an arylite substrate. Excellent adhesion of deposited C:ZnO on the flexible substrate was achieved with low sputtering power and Ar flow rate. In the fabricated device, nanostructured C:ZnO and as‐deposited thin films were used as field emitter and phosphor screen, respectively. The C:ZnO thin film showed a transparency of about 80% at 550 nm wavelength and average sheet resistance of 1.96 kΩ/□. The C:ZnO phosphor screen emitted red light during the field emission measurement, correlating the dominant cathodoluminescence peak at 646 nm. Thus, a promising transparent and flexible field emission display can be realized with C:ZnO based material.
987.
Mitsuhiko Morisue Hiroki Fukui Masaki Shimizu Kenichi Inoshita Yasuhiro Morisaki Yoshiki Chujo 《Tetrahedron letters》2014
A novel binuclear phthalocyanine tweezers, in which two zinc-phthalocyanine rings are linked to an optically active binaphthyl group through triazolyl linkages, was self-cyclized through triazolyl-to-zinc coordination bonds. An axially chiral S-binaphthyl group induced planar chirality in a slipped-cofacial stack of phthalocyanine moieties, and therefore displayed fluorescence with a good quantum yield (ΦF = 0.23) and circularly polarized luminescence with a moderate intensity of dissymmetry factor (glum = −4 × 10−4) in the near-infrared wavelength region. 相似文献
988.
Adenosine 3′,5′-cyclic monophosphorodithioate (cAMPS2), which has two exocyclic sulfurs directly attached to phosphorus, was synthesized from adenosine phosphoramidite by intramolecular cyclization employing the phosphotriester method as a key step. 相似文献
989.
Masaki Shimoi Ilia Kevlishvili Takashi Watanabe Prof. Dr. Katsuhiro Maeda Dr. Steven J. Geib Prof. Dr. Dennis P. Curran Prof. Dr. Peng Liu Dr. Tsuyoshi Taniguchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):913-919
An N-heterocyclic-carbene-ligated 3-benzoborepin with a bridged structure has been synthesized by double radical trans-hydroboration of benzo[3,4]cycloundec-3-ene-1,5-diyne with an N-heterocyclic carbene borane. The thermal reaction of the NHC-ligated borepin at 150 °C gives an isolable NHC-boranorcaradiene. Experiments and density functional theory calculations support a mechanism whereby the borepin initially rearranges to a boranorcaradiene by a thermal 6π-electrocyclic reaction. This is followed by 1,5-boron shift to give a rearranged boranorcaradiene. This shift occurs with stereoinversion at boron through a transition state with open-shell diradical character. This is the first example of the isolation of a boranorcaradiene from a thermal reaction of a borepin. 相似文献
990.
This paper reviews results from study of mononuclear ruthenium complexes capable of catalyzing the oxidation of water to molecular oxygen. These catalysts may be classified into three groups, with different rate laws associated with O2 evolution. In one class, O2 evolution proceeds via radical coupling of the oxygen atom of an RuV=O species with a hydroxocerium(IV) ion. O2 evolution catalyzed by the second class occurs via acid–base reaction of the oxygen atom of an RuV=O species with a water molecule. In the third group, the dominant mechanism is oxo–oxo radical coupling between two RuV=O species. Several significant properties of the oxidant Ce(IV) are also discussed, including the singlet biradical character of the hydroxocerium(IV) ion. 相似文献