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111.
In an isolated atom, excitation of an inner valence electron above the outer valence subshell leads to creation of an autoionizing state. Recently, it has been demonstrated experimentally that in a cluster, the inner-valence-excited states can decay also by an interatomic mechanism which has been called resonant interatomic Coulombic decay (RICD). Here we show that RICD is indeed the leading but not the only possible interatomic decay mode of the inner-valence excitations in clusters. Using Ne (2s-->3p) excitation in MgNe cluster as an example, we explore the possible decay mechanisms and draw conclusions on their relative importance and on the nature of the corresponding decay products. 相似文献
112.
Shiri Artstein-Avidan Hermann König Vitali Milman 《Journal of Functional Analysis》2010,259(11):2999-1344
We consider operators T from C1(R) to C(R) satisfying the “chain rule”
113.
Synergistic effects of sunlight exposure, thermal aging and fungal biodegradation on the oxidation and biodegradation of linear low density poly(ethylene) PE-LLD films containing pro-oxidant were examined. To achieve oxidation and degradation, films were first exposed to the sunlight for 93 days during the summer months followed by their incubation with fungal strains previously isolated from the soil based on the ability to grow on the oxidized PE-LLD as a sole carbon source. Some films were also thermally aged at temperatures ranging between 45°C and 65 °C, either before or after fungal degradation. Films with pro-oxidant additives exhibited a higher level of oxidation as revealed by increase in their carbonyl index (COi). In addition to increase in the COi, films showed a slight increase in crystallinity and melting temperature (Tm), considerably lower onset degradation temperatures, and a concomitant increase in the % weight of the residues. The level of oxidation observed in thermally aged films was directly proportional to the aging temperature. The PE-LLD films with pro-oxidant exposed to sunlight followed by thermal aging showed even higher rate and extent of oxidation when subsequently subjected to fungal biodegradation. The higher oxidation rate also correlated well with the CO2 production in the fungal biodegradation tests. Similar films oxidized and aged but not exposed to fungal biodegradation showed much less degradation. Microscopic examination showed a profuse growth and colonization of fungal mycelia on the oxidized films by one strain, while another spore-producing strain grew around the film edges. Data presented here suggest that abiotic oxidation of polymer's carbon backbone produced metabolites which supported metabolic activities in fungal cells leading to further biotically-mediated polymer degradation. Thus, a combined impact of abiotic and biotic factors promoted the oxidation/biodegradation of PE-LLD films containing pro-oxidants. 相似文献
114.
G. Schacherl H. Helbing F. W. Passmore Fr. Seiler Franz Fritzsche & Co. G. A. Raupenstrauch A. Schneider C. Engler E. Dieckhoff W. Reuss G. Chlopin M. E. Merklen Béhal Choay Pio Marfori B. Fischer Thomas Rieck M. Adrian Schmidt D. Vitali B. Hafner W. Kreissl Glücksmann C. Monheim J. Bougault und Fréd. Seiler 《Fresenius' Journal of Analytical Chemistry》1901,40(9):615-628
Ohne Zusammenfassung 相似文献
115.
Xin Zhang Guoguang Sun Marc Hovestädt Vitali Syritski Norbert Esser Rudolf Volkmer Silvia Janietz Jörg Rappich Karsten Hinrichs 《Electrochemistry communications》2010,12(10):1403-1406
We have developed and investigated a new route to functionalise Au surfaces using maleimide groups. This functionalisation has been performed by grafting aminophenyl (AP) via an electrochemical reduction of 4-aminophenyldiazonium salt in acetonitrile solution and the subsequent chemical binding of N-(2-carboxyethyl) maleimide (NCEM). The resulting maleimide functionalised surface was interacted with a cysteine-modified peptide. The grafting of AP was monitored by the occurrence of NH2 and aryl ring vibrations, whereas the binding of the NCEM led to a strong and sharp peak because of the C═O stretching mode. The immobilisation of the peptide was identified by the appearance of the amide I band. Half of the maleimide surface groups reacted with the peptide because of steric hindrance. The charge efficiency for the AP layer formation was about 45% at a thickness of about 6–8 nm. 相似文献
116.
Fausto Calderazzo Guido Pampaloni Dario Vitali Giancarlo Pelizzi Ines Collamati Sergio Frediani Anna Maria Serra 《Journal of organometallic chemistry》1980,191(1):217-242
The carbonyl adduct of phthalocyaninatoiron(II), FePc, with N,N-dimethylformamide (DMF) as axial ligand, FePc(CO)DMF, was prepared by the reaction of iron carbonyls, Fe(CO)5 or Fe2(CO)9, with o-phthaalonitrile in DMF as solvent. Several carbonyl adducts of FePc of general formula FePc (CO)L are reported, with L being a ligand with oxygen, sulphur and nitrogen donor atoms (L = tetrahydrofuran, H2O, CH3OH, dimethylsulphoxide, tetrahydrothiophene, ammonia, n-propylamine, diethylamine, triethylamine). The crystal and molecular structure of FePc(CO)DMF·DMF was investigaed by X-ray diffraction methods. The compound has a monoclinic unit cell and space group P21/n, a 9.86(1), b 17.35(3), c 19.79(4) », β 87.9(2)°, Z = 4, U 3383 »3, D3 1.458 g cm?3. The iron atom is hexacoordinated to the four inner nitrogen atoms of the macrocyle, to carbon monoxide (Fe—C distance 1.72(2) ») and to DMF (Fe—O distance 2.07(1) »). The extra DMF occupies lattice sites. All of the compounds reported in this paper are substantially diamagnetic. Mössbauer spectra show typical isomer shift parameters for the bis-adducts and for the carbonyl adduct, substantially independent of the nature of the axial ligand. The quadrupole splitting parameter of the carbonyl adducts is strongly affected by the nature of the axial ligand. 相似文献
117.
New NMR experiments are presented for the assignment of methyl (13)C and (1)H chemical shifts from Ile, Leu, and Val residues in high molecular weight proteins. The first class of pulse schemes transfers magnetization from the methyl group to the backbone amide spins for detection, while the second more sensitive class uses an "out-and-back" transfer scheme in which side-chain carbons or backbone carbonyls are correlated with methyl (13)C and (1)H spins. Both groups of experiments benefit from a new isotopic labeling scheme for protonation of Leu and Val methyl groups in large deuterated proteins. The approach makes use of alpha-ketoisovalerate that is (13)C-labeled and protonated in one of its methyl groups ((13)CH(3)), while the other methyl is (12)CD(3). The use of this biosynthetic precursor leads to production of Leu and Val residues that are (13)CH(3)-labeled at only a single methyl position. Although this labeling pattern effectively reduces by 2-fold the concentration of Leu and Val methyls in NMR samples, it ensures linearity of Val and Leu side-chain (13)C spin-systems, leading to higher sensitivity and, for certain classes of experiments, substantial simplification of NMR spectra. Very near complete assignments of the 276 Ile (delta 1 only), Leu, and Val methyl groups in the single-chain 723-residue enzyme malate synthase G (MSG, molecular tumbling time 37 +/- 2 ns at 37 degrees C) have been obtained using the proposed isotopic labeling strategy in combination with the new NMR experiments. 相似文献
118.
Vitali 《Fresenius' Journal of Analytical Chemistry》1874,13(1):476
Ohne Zusammenfassung 相似文献
119.
D. Vitali 《Fresenius' Journal of Analytical Chemistry》1904,43(6-7):466-467
Ohne Zusammenfassung 相似文献
120.