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91.
A. A. Berlin V. E. Basin M. I. Cherkashin M. G. Chauser V. A. Grigorovskaya 《Mechanics of Composite Materials》1973,9(2):326-328
The electron-donor properties of polymers with conjugation systems (PCS) and their capability of forming -complexes with metals is of interest in relation to adhesion. Small amounts (0.01–0.1%) of substances with polyconjugation systems (polydiphenylbutadiene, polyphenylacetylene, and copolymers of naphthalene and anthracene with benzene) increase the adhesion between aluminum and polymers used as electrical insulation coatings (polyesters, polyimides, and their derivatives). With optimum PCS dosage, the resistance to peeling rises by 15–38%.Institute of Chemical Physics, Academy of Sciences of the USSR, Moscow. Translated from Mekhanika Polimerov, No. 2, pp. 365–367, March–April, 1974. 相似文献
92.
V. G. Luchina Yu. D. Khamchukov V. S. Marevtsev A. V. Lyubimov A. T. Gradyushko M. I. Cherkashin 《Russian Chemical Bulletin》1988,37(10):2029-2032
Conclusions Photocoloration of spyropyran in polymethyl methacrylate and polystyrene matrices at 293 and 77 K results in the formation of a set of photoproducts with individual spectral characteristics, and the structure of a certain stereoisomer was assigned to each photoproduct based on these characteristics.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2255–2259, October, 1988. 相似文献
93.
A. M. Volodin A. E. Cherkashin K. N. Prokopiev 《Reaction Kinetics and Catalysis Letters》1992,46(2):373-378
Anion-radicals of oxygen O
2
–
and complexes of molecular oxygen with hole centers [X·O2] (g1=2.002, g2=2.009, g
3
1
=2–015, g
3
2
=2.016) and [Y·O2] (g=2.004, g=2.012) have been found to form under CaO irradiation in the range of surface absorption (h4 eV). ESR spectra of X and Y centers have not been observed. They are suggested to be anion-radicals O
st
–
in various coordinations: (O
3C
–
)st and (O
4C
–
)st, respectively.
- O 2 – [XO2] (g1=2.002, g2=2.009, g 3 1 =2.015, g 3 2 =2.016) (g=2.004, g=2.012) CaO (h4 ). X Y . , - O st – , : (O 3C – )st (O 4C – )st, .相似文献
94.
The established formation of methyl radicals on the ZnO surface due to the interaction of methane with photoinduced hole centers Os indicates that their formation and thermal destruction occur without participation of surface electron centers Zns.
ZnO O s – . , Zn s + .相似文献
95.
A. M. Volodin A. E. Cherkashin V. S. Zakharenko 《Reaction Kinetics and Catalysis Letters》1979,11(3):221-224
The paramagnetic centers of reduced anatase
(g1=1.999, g2=1.984, g3=1.979) and
(g1=2.046, g2=2.008), assigned to the stabilization of photoinduced holes near anion vacancies, have been studied. For the reduced oxide a new type of O2 photoadsorption at h >1 eV due to the generation of only electron surface centers has been discovered.
, : (g1=1,999, g2=1,984, g3=1,979) (g1=2,046, g2=2,008), . O2 h>1 , .相似文献
96.
Photoadsorption activity of SnO2 with respect to O2 and NO after CO chemisorption has been revealed to be drastically increased. Photoadsorption is suggested to be sensitized by surface carbonates formed due to CO chemisorption.
. , .相似文献
97.
98.
Viviana Scognamiglio Italo Pezzotti Gianni Pezzotti Juan Cano Ivano Manfredonia Katia Buonasera Fabiana Arduini Danila Moscone Giuseppe Palleschi Maria Teresa Giardi 《Analytica chimica acta》2012
In this paper we propose the construction and application of a portable multi-purpose biosensor array for the simultaneous detection of a wide range of endocrine disruptor chemicals (EDCs), based on the recognition operated by various enzymes and microorganisms. The developed biosensor combines both electrochemical and optical transduction systems, in order to increase the number of chemical species which can be monitored. Considering to the maximum residue level (MRL) of contaminants established by the European Commission, the biosensor system was able to detect most of the chemicals analysed with very high sensitivity. In particular, atrazine and diuron were detected with a limit of detection of 0.5 nM, with an RSD% less than 5%; paraoxon and chlorpyrifos were revealed with a detection of 5 μM and 4.5 μM, respectively, with an RSD% less than 6%; catechol and bisphenol A were identified with a limit of detection of 1 μM and 35 μM respectively, with an RSD% less than 5%. 相似文献
99.
Bulychev AA Cherkashin AA Rubin AB Vredenberg WJ Zykov VS Müller SC 《Bioelectrochemistry (Amsterdam, Netherlands)》2001,53(2):225-232
A novel experimental approach has been applied to investigate the relationship between pH banding in Chara cells and photosynthetic activity of chloroplasts located in cell regions adjacent to acid and alkaline bands. The combination of pH microelectrode technique with pulse amplitude modulation (PAM) microfluorimetry enabled parallel measurements of longitudinal pH profiles and chlorophyll fluorescence yield in acid and alkaline zones of individual Chara cells. The scanning with a pH-microelectrode along the cell length revealed the light-dependent pH pattern, i.e., alternating acid and alkaline bands with pH differences as large as 2 - 3 pH units. In parallel, measurements of chlorophyll fluorescence yield under actinic light were performed using PAM microfluorometry. It was found that the effective photochemical yield of photosystem II is substantially higher in acid than in alkaline zones. The results clearly show that the banding pattern is not confined solely to the plasmalemma but is also exhibited in alternating photosynthetic performance of the underlying chloroplast layer. Apparently, the acid regions enriched with CO2 ensure sufficient flow of this substrate to the Calvin cycle reactions, thus promoting the photosynthetic rate, whereas the alkaline zones devoid of CO2 favor radiative losses of absorbed solar energy in chloroplasts. 相似文献
100.
Francesco Ricci Nadia Zari Felice Caprio Simona Recine Aziz Amine Danila Moscone Giuseppe Palleschi Kevin W. Plaxco 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,76(1-2):208
E-DNA sensors are a reagentless, electrochemical oligonucleotide sensing platform based on a redox-tag modified, electrode-bound probe DNA. Because E-DNA signaling is linked to hybridization-linked changes in the dynamics of this probe, sensor performance is likely dependent on the nature of the self-assembled monolayer coating the electrode. We have investigated this question by characterizing the gain, specificity, response time and shelf-life of E-DNA sensors fabricated using a range of co-adsorbates, including both charged and neutral alkane thiols. We find that, among the thiols tested, the positively charged cysteamine gives rise to the largest and most rapid response to target and leads to significantly improved storage stability. The best mismatch specificity, however, is achieved with mercaptoethanesulfonic and mercaptoundecanol, presumably due to the destabilizing effects of, respectively, the negative charge and steric bulk of these co-adsorbates. These results demonstrate that a careful choice of co-adsorbate chemistry can lead to significant improvements in the performance of this broad class of electrochemical DNA sensors. 相似文献