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51.
Seiji Shinkai Seiichi Mori Takayuki Tsubaki Takaaki Sone Osamu Manabe 《Tetrahedron letters》1984,25(46):5315-5318
4-Sulfonate derivatives of calix[6]arene and O-n-hexylcalix[6]arene (1a and 1b, respectively) were synthesized. Measurements using fluorescence and absorption spectral probes indicated that the cavity of calix-[6]arene can accept a naphthalene molecule but not a pyrene molecule and that (1b) has a hydrophobic cavity constructed from the aggregate of the hexyl groups while (1a) provides a reaction field apparently more polar than water. This is the first example for water-soluble host molecules derived from calix[6]arene. 相似文献
52.
The grafting of polypropylene glycol (PPG) onto an ultrafine ferrite by the reaction of hydroxyl groups on the surface with isocyanate-capped PPG (PPG-NCO), prepared by the reaction of an equimolecular amount of PPG with tolylene 2,4-diisocyanate, was investigated. When PPG-NCO (M
n=2.5×103) was heated with the ferrite in bulk, the percentage of grafting onto the ferrite at 120 °C was increased up to 18.5%. On the contrary, the grafting by the reaction of PPG with hydroxyl groups on the ferrite at 120°C was scarcely observed. The grafted PPG onto the ferrite was removed by hydrolysis with a dilute methanol solution of potassium hydroxide. Therefore, it was considered that PPG was grafted onto the ferrite surface with urethane bond. The grafting of PPG onto the surface was also confirmed by infrared spectra. The reaction of PPG-NCO with the ferrite was accelerated by the addition of-picoline as a catalyst. PPG-grafted ferrite was found to produce a stable colloidal dispersion in organic solvents. Furthermore, the effect of molecular weight of PPG-NCO on the grafting onto the ferrite was discussed. 相似文献
53.
A. Nakajima T. Kishi Y. Sone S. Nonose K. Kaya 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,19(4):385-387
Reactivity of positively charged cobalt cluster ions (Co n + ,n=2?22), produce by laser vaporization, with various gas samples (CH4, N2, H2, C2H4, and C2H2) were systematically investigated by using a fast-flow reactor. The reactivity of Co n + with the various gas samples is qualitatively consistent with the adsorption rate of the gas to cobalt metal surfaces. Co n + highly reacts with C2H2 as characterized by the adsorption rate to metal surfaces, and it indicates no size dependence. In contrast, the reactions of Co n + with the other gas samples indicate a similar cluster size dependence; atn=4, 5, and 10?15, Co n + highly reacts. The difference can be explained by the amount of the activation energy for chemisorption reaction. Compared with neutral cobalt clusters, the size dependence is almost similar except for Co 4 + and Co 5 + . The reactivity enhancement of Co 4 + and Co 5 + indicates that the cobalt cluster ions are presumed to have an active site for chemisorption atn=4 and 5, induced by the influence of positive charge. 相似文献
54.
Yoshida K Yamaguchi K Sone T Unno Y Asai A Yokosawa H Matsuda A Arisawa M Shuto S 《Organic letters》2008,10(16):3571-3574
A series of chiral 2,3- and 3,4-methanoamino acid equivalents of stereochemical diversity were designed and synthesized from our chiral cyclopropane units, using a diastereoselective Grignard addition with ( R)- or ( S)- t-butanesulfinyl imines as the key step. These equivalents were converted into the proteasome inhibitor belactosin A and its cis-cyclopropane stereoisomer. The unnatural cis-isomer was shown to be more than twice as potent as belactosin A as a proteasome inhibitor. 相似文献
55.
A single‐wall carbon nanotube functionalized by carboxylic groups (SWNT‐CA) was found to be adsorbed on an indium tin oxide (ITO) electrode by chemical interaction between carboxylic groups and the ITO surface. The adsorption experiments indicated that the narrow pH conditions (around pH 3.0) exist for its adsorption which is restricted by preparation of stable fluid dispersion (favorable at higher pH) and by the chemical interaction (favorable at lower pH). Atomic force microscopic (AFM) measurements suggest that fragmented SWNT‐CA are adsorbed, primarily lying on the surface. Electrochemical impedance analysis indicated that an electrochemical double layer capacitance of the SWNT‐CA/ITO electrode is considerably higher than that for the ITO electrode, suggesting that the interfacial area between the electrode surface and the electrolyte solution is enlarged by the SWNT‐CA layer. Pt particles were deposited as a catalyst on the bare ITO and SWNT‐CA‐coated ITO (SWNT‐CA/ITO) electrodes to give respective Pt‐modified electrodes (denoted as a Pt/ITO electrode and a Pt/SWNT‐CA/ITO electrode, respectively). The cathodic current for the Pt/SWNT‐CA/ITO electrode was 1.7 times higher than that for the Pt/ITO electrode at 0.0 V, showing that the Pt/SWNT‐CA/ITO electrode works more efficiently for O2 reduction at 0.0 V due to the SWNT‐CA layer. The enhancement by the SWNT‐CA layer is also effective for electrocatalytic proton reduction. It could be ascribable to the enlarged interfacial area between the electrode surface and the electrolyte solution. 相似文献
56.
Catalytic asymmetric Corey-Chaykovsky epoxidation of various ketones with dimethyloxosulfonium methylide using a heterobimetallic La-Li(3)-BINOL complex (LLB) is described. The reaction proceeded smoothly at room temperature in the presence of achiral phosphine oxide additives, and 2,2-disubstituted terminal epoxides were obtained in high enantioselectivity (97%-91% ee) and yield ( > 99%-88%) from a broad range of methyl ketones with 1-5 mol% catalyst loading. Enantioselectivity was strongly dependent on the steric hindrance, and other ketones, such as ethyl ketones and propyl ketones resulted in slightly lower enantioselectivity (88%-67% ee). 相似文献
57.
58.
T. Sone 《Solid State Communications》1985,56(4):359-361
Spin glass—ferromagnetic systems such as AuFe alloys having both the ferromagnetic and RKKY interactions are studied on the basis of a mean-random-field approximation. We obtain the phase diagram of the systems in terms of the temperature and the magnetic impurity concentration. The results roughly explain the magnetism of AuFe type alloys. 相似文献
59.
Three-dimensional photochemical microfabrication of conductive polymers in transparent polymer sheet
By focused illumination at the wavelength of 800 nm using a femtosecond laser, the tris(2,2′-bipyridyl)ruthenium complex displayed
a two-photon excitation as observed by the quadratic dependence of the emission intensity on the incident laser power. Since
the oxidation of pyrrole is induced by the oxidative quenching of the excited state, polypyrrole can be formed by a continuous
illumination. The polymerization area showed a high spatial selectivity which can be scanned in the XYZ axis by a piezo device. In the present study, three-dimensional (3D) polypyrrole microstructures were formed in the transparent
polymer sheet. 相似文献
60.
Dinesh Rangappa Dr. Koji Sone Dr. Mingsheng Wang Dr. Ujjal K. Gautam Dr. Dmitri Golberg Prof. Hiroshi Itoh Dr. Masaki Ichihara Dr. Itaru Honma Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(22):6488-6494
Graphene has attracted a great deal of attention in recent years due to its unusual electronic, mechanical, and thermal properties. Exploiting graphene properties in a variety of applications requires a chemical approach for the large‐scale production of high‐quality, processable graphene sheets (GS), which has remained an unanswered challenge. Herein, we report a rapid one‐pot supercritical fluid (SCF) exfoliation process for the production of high‐quality, large‐scale, and processable graphene for technological applications. Direct high‐yield conversion of graphite crystals to GS is possible under SCF conditions because of the high diffusivity and solvating power of SCFs, such as ethanol, N‐methyl‐pyrrolidone (NMP), and DMF. For the first time, we report a one‐pot direct conversion of graphite crystals to a high yield of graphene sheets in which about 90–95 % of the exfoliated sheets are <8 layers with approximately 6–10 % monolayers and the remaining 5–10 % are ≥10 layers. 相似文献