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1.
A sensitive and specific method for the determination of bencyclane in human plasma is presented. Bencyclane was extracted from human plasma with two 3-ml volumes of isooctane and was shaken for 10 min. The organic phase was separated and evaporated to dryness at 40 degrees C under a nitrogen stream. The residue was dissolved and an aliquot was injected into the gas chromatograph. The separation was performed with a DB-17 column with helium as the carrier gas. Nitrogen-selective detection was performed. The quantification was performed with the signal output. The limit of detection was 1 ng/ml. 相似文献
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On the Preparation of Di(i-propyl)thiosulfonium Salts [1] The preparation of the mercaptosulfonium salts (i-C3H7)2SSX+SbCl6? (X = H, D) and of the chlorothiosulfonium salts (i-C3H7)2SSCl+MF6? (M = As, Sb) and (i-C3H7)2SSSCl+SbCl6? is reported. They are formed by reaction of chlorinated or protonated (i-C3H7)2S with excess H2S or SCl2 and S2Cl2. The thiosulfonium compounds are characterized by vibrational and NMR spectroscopic methods. 相似文献
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Direct Synthesis of Orthometallated Ketones of the Type RCO(o-C6H4)Mn(CO)4?nLn (R = Alkyl and Aryl Groups, n = 0, 1, 2, L = Ligand) The starting materials of the type RMn(CO)5?nLn und (C6H5)2 Hg react to the products of the type RCO(o-C6H4)Mn(CO)4?nLn[n = 0, R = Ch3, C2H5, C3H7, C6H5,CH2; R = C6H5, n = 1, L = E(C6H5)3, E = P, As, Sb; R = C6H5, n = 2, L = P(OR′)3, R′ = C6H5, CH3, C2H5, C3H7]. Steps of their complex reaction pathway are proposed. These orthometallated substances have been characterized by means of 1H-n.m.r., i.r. and u.v. spectroscopic measurements. The determination of the molecular structure of the two compounds RCO(o-C6H4)Mn(CO)3L [R = C2H5, L = CO; R = C6H5, L = As(C6H5)3] show that both contain a planar heterocyclic five-membered ring of the type . 相似文献
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Julia Post Vanessa Kogel Anja Schaffrath Philipp Lohmann N. Jon Shah Karl-Josef Langen Dieter Willbold Antje Willuweit Janine Kutzsche 《Molecules (Basel, Switzerland)》2021,26(6)
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterised by selective neuronal death in the brain stem and spinal cord. The cause is unknown, but an increasing amount of evidence has firmly certified that neuroinflammation plays a key role in ALS pathogenesis. Neuroinflammation is a pathological hallmark of several neurodegenerative disorders and has been implicated as driver of disease progression. Here, we describe a treatment study demonstrating the therapeutic potential of a tandem version of the well-known all-d-peptide RD2 (RD2RD2) in a transgenic mouse model of ALS (SOD1*G93A). Mice were treated intraperitoneally for four weeks with RD2RD2 vs. placebo. SOD1*G93A mice were tested longitudinally during treatment in various behavioural and motor coordination tests. Brain and spinal cord samples were investigated immunohistochemically for gliosis and neurodegeneration. RD2RD2 treatment in SOD1*G93A mice resulted not only in a reduction of activated astrocytes and microglia in both the brain stem and lumbar spinal cord, but also in a rescue of neurons in the motor cortex. RD2RD2 treatment was able to slow progression of the disease phenotype, especially the motor deficits, to an extent that during the four weeks treatment duration, no significant progression was observed in any of the motor experiments. Based on the presented results, we conclude that RD2RD2 is a potential therapeutic candidate against ALS. 相似文献
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Eine Meßapparatur zur Untersuchung des Kriech- und Relaxationsverhaltens von Polymeren unter Torsion
Zusammenfassung Zur experimentellen Bestimmung der Kriechfunktion J(t) und der Relaxationsfunktion G(t) unter Torsionsbelastung der Probe wurde eine Meßapparatur entwickelt. Das mechanisch-elektrische Meßprinzip sowie eine Prozeßrechnerkopplung gestatten einen weitgehend automatischen Meßbetrieb. Änderungen an den physikalischen Versuchsbedingungen können rein Software-seitig durchgeführt werden.Das entsprechende Auswerteprogramm liefert neben numerischen Werten eine Zeichnung der entsprechenden Masterkurven, die mit Hilfe der WLF-Gleichung konstruiert werden.Messungen an kommerziellem PMMA zeigen einen Meßz bereich fürJ(t) von 10–9 bis 10–5 m2/N und für G(t) von 10° bis N 105
N/m2 ; das zugängliche Temperaturintervall liegt zwischen –180 °C und 200 °C. Damit ist der für die meisten Polymere erforderliche Bereich erfaßt.Mit 9 Abbildungenjetzt: KFA Jülich GmbH, Institut für Festkörperforschung (IFF). 相似文献
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Yu. Arestov A. Borovikov E. Kozlovsky A. Minaenko A. Moiseev C. Cochet D. Denegri C. Lewin M. A. Turluer U. Gensch H. J. Grabosch W. Lohmann J. MacNaughton France-USSR Collaboration CERN-USSR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1981,8(4):283-289
New data on the inclusive production of the non-strange resonances ?0(770), ω(783), ?(1020) andf(1270) inK ? p interactions at 32 GeV/c are presented. The inclusive production cross sections are equal to (4.32±0.72) mb, (3.7±1.4) mb, (0.65±0.10) mb and (0.91±0.35) mb respectively. Estimates of the topological cross sections are also obtained. The invariant and non-invariantx-distributions for the vector mesons ?0 and ? indicate the prevalence of forward resonance production in the c.m. system. For the tensorf-meson the rapidity andx-distributions are presented. Thet′-distributions for ?0, ?, andf have exponential slopes of 0.6±0.1 GeV?2, 1.2±0.2 GeV?2, and 0.8±0.5 GeV?2 respectively. The exponential slope ofp T 2 -distribution of thef-meson is equal to (2.3±0.5) GeV?2. 相似文献
10.
EI Rodriguez Martinez CI Barriga-Paulino MI Zapata CC Chinchilla AM López-Jiménez CM Gómez 《BMC neuroscience》2012,13(1):104-23
ABSTRACT: BACKGROUND: The peri-adolescent period is a crucial developmental moment of transition from childhood to emergent adulthood. The present report analyses the differences in Power Spectrum (PS) of the Electroencephalogram (EEG) between late childhood (24 children between 8 and 13 years old) and young adulthood (24 young adults between 18 and 23 years old). RESULTS: The narrow band analysis of the Electroencephalogram was computed in the frequency range of 0--20 Hz. The analysis of mean and variance suggested that six frequency ranges presented a different rate of maturation at these ages, namely: low delta, delta-theta, low alpha, high alpha, low beta and high beta. For most of these bands the maturation seems to occur later in anterior sites than posterior sites. Correlational analysis showed a lower pattern of correlation between different frequencies in children than in young adults, suggesting a certain asynchrony in the maturation of different rhythms. The topographical analysis revealed similar topographies of the different rhythms in children and young adults. Principal Component Analysis (PCA) demonstrated the same internal structure for the Electroencephalogram of both age groups. Principal Component Analysis allowed to separate four subcomponents in the alpha range. All these subcomponents peaked at a lower frequency in children than in young adults. CONCLUSIONS: The present approaches complement and solve some of the incertitudes when the classical brain broad rhythm analysis is applied. Children have a higher absolute power than young adults for frequency ranges between 0-20 Hz, the correlation of Power Spectrum (PS) with age and the variance age comparison showed that there are six ranges of frequencies that can distinguish the level of EEG maturation in children and adults. The establishment of maturational order of different frequencies and its possible maturational interdependence would require a complete series including all the different ages. 相似文献