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91.
92.
Janne?Gr?hnEmail author Artur?Nicolau Jouni?R?tty? 《Journal d'Analyse Mathématique》2018,134(2):747-768
The aim of this paper is to consider certain conditions on the coefficient A of the differential equation f″ + Af = 0 in the unit disc which place all normal solutions f in the union of Hardy spaces or result in the zero-sequence of each non-trivial solution being uniformly separated. The conditions on the coefficient are given in terms of Carleson measures. 相似文献
93.
Helle A Hirsjärvi S Peltonen L Hirvonen J Wiedmer SK 《Journal of chromatography. A》2008,1178(1-2):248-255
Capillary electrophoretic (CE) methods were used for the quantitative determination of model drugs [salbutamol sulphate (SS), sodium cromoglycate (SCG) and beclomethasone dipropionate (BDP)] in poly(D,L-lactic acid) (PLA) nanoparticles, which were prepared by the nanoprecipitation method. Zeta potential and size distribution of the nanoparticles were determined by electrophoretic mobility determinations and photon correlation spectroscopy, respectively. Interactions between the drugs, the PLA nanoparticles and the fused-silica capillary were investigated by electrokinetic capillary chromatography (EKC). A quantitative CE method was developed for salbutamol sulphate and sodium cromoglycate, and the linearity and repeatability of migration times, peak areas and peak heights were determined. Microemulsion electrokinetic chromatography was used for the quantitative determination of beclomethasone dipropionate. According to this study, the applied electromigration techniques were suitable for the interaction, drug entrapment and dissolution studies of pharmaceutical nanoparticles. The results suggest that even quantitation of the drug located inside the nanoparticles was possible. Encapsulation of the more hydrophilic model drugs (SS, SCG) in the PLA nanoparticles was less efficient than in the case of BDP. 相似文献
94.
Bobacka J Alaviuhkola T Hietapelto V Koskinen H Lewenstam A Lämsä M Pursiainen J Ivaska A 《Talanta》2002,58(2):341-349
Ion-selective electrodes (ISEs) based on pi-coordinating carriers were prepared and investigated as potentiometric sensors for aromatic cations, using N-methylpyridinium as a model aromatic cation. Derivatives of tetraphenylborate were studied as charged carriers in plasticized poly(vinyl chloride) membranes. Furthermore, neutral compounds containing pi-coordinating anthryl groups were studied as neutral carriers. Bis(2-ethylhexyl)sebacate (DOS) and 2-nitrophenyl octyl ether (o-NPOE) were used as non-polar and polar plasticizer, respectively. ISEs were constructed by using poly(3,4-ethylenedioxythiophene) (PEDOT) as solid-contact material. Conventional ISEs with internal filling solution were used for comparison. The potentiometric responses of the ISEs were investigated using N-methylpyridinium as primary ion. The results show that the selectivity of the ISEs is influenced significantly by both the plasticizer and the charged carriers, while the neutral carriers studied have only a minor influence on the selectivity. The role of cation-pi interactions between aromatic cations and the membrane components is discussed. 相似文献
95.
The single-state-dominance hypothesis (SSDH) states that the decay rates of the two-neutrino double beta decay are governed by a virtual two-step transition connecting the initial and final ground states through the first 1+ state, 1
1
+
, of the intermediate odd-odd nucleus, for those odd-odd nuclei where the 1
1
+
state is the ground state. To investigate the validity the SSDH we have performed a systematical theoretical analysis of all known double-beta-decay transitions where the SSDH conditions are fulfilled. The analysis shows that the SSDH is realized either through a true dominance of the first intermediate 1+ state or by cancellations among the contributions of higher lying 1+ states of the intermediate nucleus. 相似文献
96.
We discuss the nuclear structure elements participant in the calculation of the half-life of the neutrinoless double beta
decay, and the consequences upon the adopted limits of the electron-neutrino mass.
Presented by O. Civitarese at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’05), Corfu, Greece,
September 26–29, 2005. 相似文献
97.
98.
A study concerning the valence space dependence of neutrinoless doubleβ
− decay observables is performed for several nuclei in the framework of QRPA using the multiple commutator method (MCM). Calculations
and comparison to earlier results show that at least for the ground state to ground state transition the dependence is much
weaker than in the two neutrino doubleβ
− decay. It is still a difficult task to extract the parameters of the neutrinoless doubleβ
− decay since the half-life expression contains products of the parameters 〈m
ν
〉 〈η〉 and 〈λ〉.
Presented by M. Aunola at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’97), Prague, May 27–31,
1997. 相似文献
99.
M. Andreina Moreno Sirpa Jääskeläinen Jouni Pursiainen 《Journal of organometallic chemistry》2005,690(16):3803-3814
A series of ruthenium o-phosphane complexes was synthesized and characterized. The reactivity of the prepared complexes was studied by using them as catalysts for the hydroformylation of 1-hexene. The activities depended on the binding mode of the phosphane and on the strength of the ruthenium-phosphane interaction. Strongly coordinated chelating [2-(dimethylamino)phenyl]-(diphenyl) phosphane and [2-(methylthio)phenyl]-(diphenyl) phosphane showed poor activity, while weakly chelated [2-(methoxy)phenyl]-(diphenyl) phosphane and non-chelating phosphanes such as [2-(methyl)phenyl]-(diphenyl) phosphane or [2-(ethyl)phenyl]-(diphenyl) phosphane led to higher activities. 相似文献
100.
A novel heterobidentate chiral phosphine and its coordination chemistry in transition metal clusters
Marina M. Tomashevskaya Ivan S. Podkorytov Jonathan A. Iggo Tapani A. Pakkanen Jouni Pursiainen 《Journal of organometallic chemistry》2007,692(14):2911-2923
The optically active ligand R,R-PHAZAN (1,3-bis[(1R)-1-Phenylethyl]-2-(2-thienyl)-1,3,2-diazaphospholane) has been prepared and the products resulting from the reactions with Rh6(CO)15NCMe, H3RhOs3(CO)12, and H4Ru4(CO)12 have been investigated by X-ray crystallography and a variety of multinuclear NMR methods. X-ray studies show that PHAZAN can behave as a bidentate ligand in Rh6(CO)14(μ2,κ2-R,R-PHAZAN) (with coordination through P and S) or a monodentate ligand (through P coordination) in H4Ru4(CO)11(κ1-R,R-PHAZAN) and NMR studies show that these structures are retained in solution. In Rh6(CO)14(μ2,κ2-R,R-PHAZAN), edge-bridging coordination of PHAZAN results in the formation of an additional two novel chiral centres and these are observed in solution. Reaction of PHAZAN with H3RhOs3(CO)12 results in cleavage of the thienyl group and formation of the phosphido cluster, H2RhOs3(CO)11(μ2-PNN), (PNN = 1,3-bis-(1-phenylethyl)-[1,3,2]diazaphospholidine-2-yl). A variety of NMR measurements show that the hydride site-occupancies in the solid state are retained in solution and there is evidence for interaction of an ortho-phenyl hydrogen and a hydride through “dihydrogen” bonding. 相似文献