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91.
92.
Thermosensitive 4VP‐NIPAAm‐4G copolymer beads containing pyridyl groups were first prepared by suspension copolymerization of 4‐vinylpyridine (4VP), N‐isopropylacrylamide(NIPAAm), and tetraethylene glycol dimethacrylate (4G; crosslinking reagent) in a saturated Na2SO4 aqueous solution in the presence of surfactant and MgCO3 as dispersants. Then the copolymer beads containing pyridinium groups were obtained by the quaternization of the copolymer beads with various alkyl iodides (CH3I, C4H9I, C8H17I) in N,N‐dimethylformamide. The 4VP‐NIPAAm‐4G (15 : 97 : 3) copolymer bead and the 4VP‐NIPAAm‐4G copolymer beads quaternized with butyl iodide exhibited high thermosensitivity in water, although the 4VP‐NIPAAm‐4G copolymer beads quaternized with methyl iodide or octyl iodide hardly exhibited thermosensitivity. All the quaternized copolymer beads exhibited antibacterial activity against Escherichia coli (E. coli), although the 4VP‐NIPAAm‐4G copolymer bead did not. In particular, the copolymer bead quaternized with butyl iodide exhibited the highest antibacterial activity against E. coli at 30°C. It was also found that the antibacterial activity of the quaternized 4VP‐NIPAAm‐4G copolymer beads was greatly affected by not only chain length of alkyl groups in alkyl iodides, with which the 4VP‐NIPAAm‐4G copolymer beads were quaternized, but also by temperature of the solutions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
93.
Fujisaki Y Tsukune T Funyû M Okumura M Ukigaya T Sugibayashi K 《Drug development and industrial pharmacy》2006,32(2):207-217
We have developed a 200 mg and 400 mg sustained-release sodium valproate tablet that allows effective blood concentration of the active drug with once-a-day dosing. The controlled dissolution or sustained release of the drug was attained by a membrane-controlled system. A single-coating system did not adequately control the dissolution rate, and therefore double-coated tablets were prepared and a human pharmacokinetic study was conducted. With the 200 mg VPA-Na tablets, the nonfasting Cmax was only 20% higher than the fasting Cmax. An in vitro dissolution test was conducted to predict the effects of food on drug dissolution after administration of this tablet. A relatively good correlation was observed between the absorption profiles and the dissolution profiles of the drug. 相似文献
94.
Eiji Akiyama Songjie Li Tadashi Shinohara Zuogui Zhang Kaneaki Tsuzaki 《Electrochimica acta》2011,(4):1799
Electrochemical hydrogen permeation tests of Fe sheets under two cyclic corrosion test (CCT) conditions were performed to understand hydrogen entry behavior under atmospheric corrosions. Hydrogen entry into 1300 MPa-class high strength steels under two CCT conditions was also investigated using thermal desorption analysis. One CCT consisted of salt spray, dry and wet stages (Salt Spray CCT; SSCCT), and the other consisted of dry and wet stages after NaCl deposition (Dry–Wet CCT; DWCCT). The corrosion rates of Fe and the steels were almost constant under SSCCT and they decreased under DWCCT with time. Nevertheless, both CCTs resulted in increases in hydrogen permeation current and diffusible hydrogen content with time indicating enhancement of hydrogen entry. Corrosion current monitored by means of an atmospheric corrosion monitoring sensor consisting of Fe anode and Ag cathode decreased obviously under dry stage of the CCTs, whereas hydrogen permeation was high at the beginning of the dry stage. The discrepancy between hydrogen entry and corrosion rate indicates that the hydrogen entry is not directly controlled by corrosion rate. Increase in acidity of underlying rust layer with growth of rust layer monitored using a W/WO3 electrode is considered to be one of the factors affecting the hydrogen entry efficiency. 相似文献
95.
Noriaki Takagi Yoshinobu Izumi Kimiko Ema Tadashi Yamamoto Kazushige Nishizawa 《溶剂提取与离子交换》2013,31(6):1461-1471
ABSTRACT Dicyclohexano- 18-crown-6 (DC18C6), dissolved in chloroform, 1-octanol, toluene or cyclohexane, was irradiated by 60Co γ-rays. Radiolytic destruction of DC18C6, measured by gas chromatography, decreased in the order: chloroform > cyclohexane > 1-octanol > toluene. Distribution coefficients in the solvent extraction of strontium from nitric acid solution were measured. These distribution coefficients were minimally affected by γ-irradiation in toluene solution, but decreased with the absorbed dose in chloroform solution. It was suggested that the distribution coefficient for the liquid-liquid extraction system was influenced by radiolytic products. The effect of radiolytic products on the distribution coefficients was evaluated by considering DC18C6 remaining in the organic phase after irradiation. The distribution coefficient measured for the organic phase with radiolytic products was larger than that without radiolytic products. The radiolytic products were thus shown to contribute to the increase in the distribution coefficient. 相似文献
96.
Yuzo Nishida Satoshi Nishino Li Li Guo Mami Kunita Hideaki Matsushima Tadashi Tokii 《Inorganic chemistry communications》1999,2(12):160
We have observed that binuclear cobalt(II) compounds with H(HPTP), Co2(HPTP)(CH3COO)(ClO4)2 and Co2(HPTP)Cl(ClO4)2, react with oxygen molecules when DNA is present in the solution, cleaving the DNA (H(HPTP) denotes N,N,N′,N′-tetrakis(2-pyridylmethyl)-1,3-diaminopropane-2- ol). 相似文献
97.
Zhong Xiangyu Hamdani Fethi Xu Jian Shoji Tetsuo Tatsuki Tadashi Morii Jun Sasaki Wakako Ishii Yasunori 《Oxidation of Metals》2019,91(5-6):705-727
Oxidation of Metals - Oxide scale control is one of the critical maintenance issues in fossil fuel power plant. Hence, the water treatment of the feed water has been changed from all-volatile... 相似文献
98.
Tsukasa Miyagi Shin‐ichi Tanaka Mikimasa Iwata Tadashi Amakawa 《Electrical Engineering in Japan》2015,190(3):30-36
This paper describes experimental and analytic studies on pressure rise and propagation phenomena due to high current arcs in a container with opened pipes. The shape of the experimental container was chosen taking into account underground common ducts. First, arcs were ignited in the container with varying diameter D and length L of the opened pipes and at arc currents of 4 kA to 12.5 kA and an arc duration of 0.1 s. Based on measured waveforms, the maximum pressure rise and the pressure oscillation frequency were obtained. It was found that there is a tendency for to increase with decreasing D and increasing L, and that D has a much greater impact on . In addition, the tendencies of with changing D and L can be approximately explained by Helmholtz resonance. Second, a CFD model for the container with opened pipe was developed based on the experimental results, and simulations were performed. The simulation results were found to correspond to the experimental pressure rise. 相似文献
99.
Katsuyama Yutaka Ishida Yukinori Ishihara Koushi Miyashita Tadashi Tsuchiya Haruhiko 《Electronics letters》1979,15(3):94-95
A new method for determining suitable single-mode fibre parameters is examined. Suitable fibre parameters are determinable by minimising cabling- and splicing-loss increases. An eight-fibre cable was manufactured and the loss increases were measured. ? = 0.2% and V = 2.2 are the values selected using this method and for the experimental results. 相似文献
100.
Yusuke Yamada Atsushi Ueda Zhen Zhao Toru Maekawa Kengo Suzuki Tadashi Takada Tetsuhiko Kobayashi 《Catalysis Today》2001,67(4):325-387
The rapid evaluation of catalysis is an indispensable technology for the success of combinatorial chemistry. A small-sized, less expensive, easily operating screening is desirable for parallel settings which dramatically shortens the evaluation time. Recent advances in gas sensors have enabled us to use them for the rapid evaluation of oxidation catalysis. Three typical catalytic oxidations over metal oxide catalysts were evaluated by gas sensor systems optimized for each catalytic system. The first one is the total oxidation of carbon monoxide in air. Five catalytic combustion-type gas sensors were used in a parallel reactor system to shorten the evaluation time. The second one is the oxidative dehydrogenation (ODH) of ethane over the mixed oxide of nickel and iron. The evaluation of the ODH catalysis was performed by a selective olefin sensor which determines the concentration of C2H4 in C2H6. The third one is the selective oxidation catalysis of propane over alkali modified Fe/SiO2. The effluents including CO, CO2, aldehydes and ketones in propane were analyzed by the CO, CO2 and semiconductor-type gas sensors selective toward aldehydes and ketones. These evaluation results indicated that gas sensors have a good potential for the rapid evaluation of oxidation catalysts. 相似文献