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91.
A novel tripodal ligand, tris[(4'-methyl-2,2'-bipyridyl-4-yl)methyl]carbinol (L), has been synthesized. The spectroscopic, electrochemical, and photocatalytic properties of the new trinuclear complexes (Ru(2)Re and RuRe(2)) linked by the tripodal bridging ligand L are then investigated. In addition, 2-fold-improved photocatalytic activities were obtained in the case of these trinuclear complexes compared to the mixtures of the appropriate monometallic model complexes in the reduction of CO(2) under visible irradiation. 相似文献
92.
Kaoru Taketani Kenji Mishima Takashi Ino Tamaki Yoshioka Suguru Muto Takahiro Morishima Hirohiko M. Shimizu Takayuki Oku Junichi Suzuki Takenao Shinohara Kenji Sakai Hiromi Sato Katsuya Hirota Yoshie Otake Masaaki Kitaguchi Masahiro Hino Yoshichika Seki Yoshihisa Iwashita Masako Yamada Masahiro Ichikawa Takanori Sugimoto Shinsuke Kawasaki Sachio Komamiya Yoshio Kamiya Hidetoshi Otono Satoru Yamashita Peter Geltenbort 《Physica B: Condensed Matter》2009,404(17):2643-2645
We obtained highly polarized very cold neutrons through a quadrupole magnet with a large aperture. When neutrons go through a quadrupole magnet, parallel-spin neutrons are attracted to the magnet axis and anti-parallel-spin neutrons are repelled off the axis. Therefore, the neutrons through a sufficiently long quadrupole magnet have completely parallel-spin. At the downstream of the quadrupole magnet, we placed another quadrupole magnet to divide neutrons into two regions depending on their spin directions. We obtained the neutron polarization from the integrated count of the two regions and found it was 99.88±0.09 (stat.)±0.05 (syst.)%. 相似文献
93.
Teiichiro Ito Mitsuru Yamai Toshiyuki Nishio Tadatake Oku 《Journal of carbohydrate chemistry》2013,32(3):491-498
Abstract The 13C NMR signals of methyl tri-O-acetyl-l-arabinofuranosides were assigned on the basis of heteronuclear shift correlated NMR spectra. From the enzymic digest of barley-hull arabinoxylan two oligosaccharides, i.e., α-l-Araf-(1→3)-β-d-xylp-(1→4)-d-xylp and α-l-Araf-(1→3)-β-d-xylp-(1→4)-β-d-xylp-(1→4)-d-xylp were obtained. The NMR spectra of their per-O-acetylated derivatives were assigned, and discussed. 相似文献
94.
Naofumi Ohtsu Akiko Nomura Masaoki Oku Toetsu Shishido Kazuaki Wagatsuma 《Applied Surface Science》2008,254(17):5336-5341
Oxidation behaviors of NiAl, Ni3Al, and FeAl under oxygen atmosphere at low pressures were studied by X-ray photoelectron spectroscopy (XPS). Clean surfaces of these aluminides were prepared by fracturing in an ultra high vacuum, and then the fractured surfaces were oxidized by exposing to high-purity oxygen at pressures up to 1.3 Pa without exposing to air. The oxides formed on NiAl and FeAl surfaces were Al2O3, whereas the oxide on Ni3Al was NiAl2O4. Aluminum, nickel, and iron on clean surfaces were oxidized even at a pressure of 1.3 × 10−6 Pa. The oxidation evolves with an increase in the pressure of oxygen, and further oxidation of aluminum occurs prior to that of nickel or iron. The oxidation behaviors under such oxygen atmosphere were similar to those of the aluminides oxidized in air, and these behaviors could be predicted from thermodynamic consideration. 相似文献
95.
Takeo Oku Takanori Hirano Satoru Nakajima Katsuaki Suganuma Eiji Aoyagi Kenji Hiraga 《Molecular Crystals and Liquid Crystals》2013,570(1):799-804
Abstract Formation of carbon nanocapsules with various clusters (SiC, Au, Fe. Co. Ge. and GeO2) by polymer pyrolysis was investigated, and nanocapsules with SiC and Au nanoparticles were produced by thermal decomposition of polyvinyl alcohol at ?500°C in Ar gas atmosphere. The formation mechanism of nanocapsules and a structural model for the nanocapsule/SiC interface were proposed. In addition, carbon clusters were formed at the surface of carbon nanocapsules, and carbon onions were produced by electron irradiation of amorphous carbon produced from polyvinyl alcohol. The present work indicates that the pyrolysis of polymer materials with clusters is a useful fabrication method for the mass-production of carbon nanocapsules and onions at low temperatures compared to the ordinaly are discharge method. 相似文献
96.
Kazuhisa Fujimoto Masaoki Kajino Masahiko Inouye 《Research on Chemical Intermediates》2013,39(1):311-319
A variety of fluorophores were introduced at the N-termini of short peptides for use as biological-probes. The fluorescent peptides were cross-linked with a diacetylenic cross-linking agent between the amino acid side chains of ornithine (Orn) residues to produce peptides with high helix content. 相似文献
97.
H. Takeuchi Y. Yamamoto Y. Kamo T. Oku M. Nakayama 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,52(3):311-314
We have investigated electric field strengths in the AlxGa1-xN layer, FAlGaN's, of AlxGa1-xN/GaN heterostructures with and without a GaN cap layer using photoreflectance (PR) spectroscopy. Franz-Keldysh oscillations
(FKOs) from the AlxGa1-xN layer are clearly observed in the PR spectra. It is found from analysis of the FKOs that stacking of the cap layer causes
a remarkable enhancement of FAlGaN. This fact demonstrates that the FKO profile is a non-destructive probe for a change of built-in electric field strength
induced by a cap layer. Numerical calculations of FAlGaN based on a Schr?dinger-Poisson equation clarify that the magnitude of the enhancement of FAlGaN is dominated by the cap-layer thickness. 相似文献
98.
Possibility of hydrogen gas storage in carbon (C) and boron nitride (BN) clusters was investigated by molecular orbital calculations. Chemisorption calculation was carried out for C60, B24N24 and B36N36 with changing position of hydrogen atom to compare the bonding energy at carbon, nitrogen and boron, tetragonal and hexagonal rings. Chemisorption calculation of hydrogen for BN clusters showed that hydrogen bondings with nitrogen atoms and tetragonal rings were the most stable. Stability of H2 molecules inside BN and C clusters was also investigated by molecular orbital calculations. C and BN clusters showed possibility of hydrogen storage of 6.5 and 4.9 wt%, respectively. 相似文献
99.
Bunichiro Yamada Fuminori Oku Takahiro Harada 《Journal of polymer science. Part A, Polymer chemistry》2003,41(5):645-654
The addition of propagating radicals of methyl acrylate (MA) and styrene (St) to CH2?C(CO2CH3)CH2? and CH2?C(C6H5)CH2? ω‐end groups of poly(methyl methacrylate) (PMMA) and polystyrene (PSt) was investigated. The end groups were as reactive as MA and St toward the poly(methyl acrylate) (PMA) and PSt radicals, respectively. The adduct radical derived from the two types of PMMA end groups and PMA radicals underwent β fragmentation exclusively to yield PMMA radicals and end groups bound to PMA chains. The addition of PSt radicals to PMMA with CH2?C(CO2Me)CH2? end groups resulted in adduct radicals that underwent β fragmentation and addition to St or coupling with PSt radicals. Adduct radicals formed by the addition of PMA radicals to both types of end groups of PSt exclusively formed C? C bond by coupling with PMA radicals to form branched structures or by addition to MA monomer to give a copolymer. The fate of the adduct radicals was highly dependent on the type of polymer chain and the substituent bound to the end group. Steric congestion of the adduct radical arising from the α‐methyl group of the PMMA chain was considered to be crucial for fragmentation to expel the PMMA radical. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 645–654, 2003 相似文献
100.
Covalently linked dimers of Ru(bpy)3 2+ (3 and 4) connected by two or three carbon atoms were synthesized as models for Ru(bpy)3 2+-containing vinyl polymer (1). The luminescence properties of 3 and 4 were compared with those of its component monomer, 4,4′-dimethyl-2,2′-bipyridine-bis(2,2′-bipyridine)ruthenium(II) complex (2). In excited 3 and 4, intramolecular interaction leading to enhanced quenching was not observed. Electron-transfer quenching of the excited dimer with methylviologen (MV2+) and the zwitterionic viologen, 1,1′-bis(3-sulfopropyl)4,4′-bipyridinium (SPV), was studied and compared with that of 1 and 2. The low quenching efficiency in 1, 3, and 4 systems can be ascribed to the steric hindrance of unexcited ruthenium complex. Energy migration between ruthenium complexes in the excited 1, 3, and 4 can be ruled out from the kinetic evidence. 相似文献