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91.
T. Caruso C. Lenardi T. Mazza A. Policicchio R.G. Agostino E. Colavita K.C. Prince P. Piseri P. Milani 《Surface science》2007,601(13):2688-2691
Nanostructured titanium dioxide (ns-TiO2) films were grown by supersonic cluster beam deposition method. Transmission electron microscopy demonstrated that films are mainly composed by TiO2 nanocrystals embedded in an amorphous TiO2 phase while their electronic structure was studied by photoemission spectroscopy. The cluster assembled ns-TiO2 films are expected to exhibit several structural and chemical defects owing to the large surface to volume ratio of the deposited clusters. Ultraviolet photoemission spectra (hv = 50 eV) from the valence band unveil the presence of a restrained amount of surface Ti 3d defect states in the band gap, whereas Ti 2p core level X-ray photoelectron (hv = 630 eV) spectra do not manifestly disclose these defects. 相似文献
92.
Dr. Stefano Tommasone Dr. Carmen Talotta Prof. Carmine Gaeta Luigi Margarucci Dr. Maria Chiara Monti Prof. Agostino Casapullo Dr. Beatrice Macchi Dr. Salvatore Pasquale Prete Dr. Adriana Ladeira De Araujo Prof. Placido Neri 《Angewandte Chemie (International ed. in English)》2015,54(51):15405-15409
MS‐based chemical‐proteomics technology is introduced herein as a third general strategy to study the biomolecular recognition properties of given calixarene derivatives. In particular, we demonstrate that a simply designed calix[4]arene derivative 1 a bearing acetamido groups at the exo rim (pAC), when linked to a solid support, is able to fish out a specific protein (PDI protein) from a crude extract of HeLa cells. Western blot and surface plasmon resonance studies confirmed the direct interaction between PDI and the linker‐free pAC derivative 1 b with considerable affinity, and in vitro tests showed its inhibition of PDI chaperone activity. In accordance with the role of PDI in a variety of human cancers, biological tests showed that pAC 1 b was cytotoxic and cytostatic toward CAL‐27 and PC‐3 cancer cell lines in vitro. Docking studies showed that H bonds and hydrophobic interactions contribute to the stabilization of the PDI/pAC complex. 相似文献
93.
Puzzarini C Cazzoli G Baldacci A Baldan A Michauk C Gauss J 《The Journal of chemical physics》2007,127(16):164302
Guided by theoretical predictions, the rotational spectra of the mono- and bideuterated species of bromofluoromethane, CDH(79)BrF, CDH(81)BrF, CD(2) (79)BrF, and CD(2) (81)BrF, have been recorded for the first time. Assignment of a few hundred rotational transitions led to the accurate determination of the ground-state rotational constants, all of the quartic and most of the sextic centrifugal distortion constants, as well as the full bromine quadrupole-coupling tensor for both (79)Br and (81)Br, in good agreement with corresponding theoretical predictions based on high-level coupled-cluster calculations. The rotational spectra of the (13)C containing species (13)CH(2) (79)BrF and (13)CH(2) (81)BrF have been observed in natural abundance and have been assigned, thus allowing the determination of the rotational and centrifugal distortion constants as well as the bromine quadrupole-coupling tensor. Furthermore, empirical equilibrium structures have been obtained within a least-squares fit procedure using the available experimental ground-state rotational constants for various isotopic species. Vibrational effects have been accounted for in the analysis using vibration-rotation interaction constants derived from anharmonic force fields computed at the second-order Moller-Plesset perturbation theory as well as coupled-cluster (CC) levels. The empirical equilibrium geometries obtained in this way agree well with the corresponding theoretical predictions obtained from CC calculations [at the CCSD(T) level] after extrapolation to the complete basis set limit and inclusion of core-valence correlation corrections and relativistic effects. 相似文献
94.
Migliore A Corni S Felice RD Molinari E 《The journal of physical chemistry. B》2007,111(14):3774-3781
Recent experimental and theoretical investigations show that water molecules between or near redox partners can significantly affect their electron-transfer (ET) properties. Here we study the effects of intervening water molecules on the electron self-exchange reaction of azurin (Az), by performing a conformational sampling on the water medium and by using a newly developed ab initio method to calculate transfer integrals between molecular redox sites. We show that the insertion of water molecules at the interface between the copper active sites of Az dimers slightly increases the overall ET rate, while some favorable water conformations can considerably enhance the ET kinetics. These features are traced back to the interplay of two competing factors: the electrostatic interaction between the water and protein subsystems (mainly opposing the ET process for the water arrangements drawn from MD simulations) and the effectiveness of water in mediating ET coupling pathways. Such an interplay provides a physical basis for the found absence of correlation between the electronic couplings derived through ab initio electronic structure calculations and the related quantities obtained through the Empirical Pathways (EP) method. In fact, the latter does not account for electrostatic effects on the transfer integrals. Thus, we conclude that the water-mediated electron tunneling is not controlled by the geometry of a single physical pathway. We discuss the results in terms of the interplay between different ET pathways controlled by the conformational changes of one of the water molecules via its electrostatic influence. Finally, we examine the dynamical effects of the interfacial water and check the validity of the Condon approximation. 相似文献
95.
Baldacci A Stoppa P Charmet AP Giorgianni S Cazzoli G Puzzarini C Larsen RW 《The journal of physical chemistry. A》2007,111(30):7090-7097
A spectroscopic study of CH279BrF in the infrared and microwave regions has been carried out. The rovibrational spectrum of the nu5 fundamental interacting with 2nu6 has been investigated by high-resolution FTIR spectroscopy. Owing to the weakness of the 2nu6 band, the v6 = 2 state constants have been derived from v6 = 1. For this reason, the rotational spectra of the ground and v6 = 1 states have been observed by means of microwave spectroscopy. Highly accurate ab initio computations have also been performed at the CCSD(T) level of theory in order to support the experimental investigation. As far as the nu5 band is concerned, the analysis of the rovibrational structure led to the identification of more than 3000 transitions, allowing the determination of a set of spectroscopic parameters up to sextic distortion terms and pointing out first-order c-type Coriolis interaction with the v6 = 2 state. With regard to the pure rotational spectra measurements, the assignment of several DeltaJ = 0, +1 transitions allowed the determination of the rotational, all the quartic, and most of the sextic centrifugal distortion constants, as well as the full bromine quadrupole coupling tensor for both the ground and v6 = 1 states. 相似文献
96.
G Giardina P D’Agostino G Fazio M Herman AI Muninov A Nasirov G Oliva R Palamara R Ruggeri 《Pramana》1999,53(3):409-418
The fusion-fission reaction mechanism leading to the massive nucleus formation is studied. We investigate the superheavy nucleus
formation in heavy-ion induced reactions by analysing the evaporation residue (ER) production in order to study the fusion
dynamics and the decay properties of nuclei close to the stability island at Z=114. We consider the 61Ni+208Pb, 48Ca+238U and 48Ca+244Pu reactions that lead to the Z=110, 112 and 114 superheavy elements respectively.
By using the dinuclear system (DNS) concept of the two interacting nuclei we calculate the quasifission-fusion competition
in the entrance channel and the fission-evaporation competition along the de-excitation cascade of the compound nucleus. The
dynamics of the entrance channel allows us to determine the beam energy window which is favorable to the fusion, while the
dynamic evolution of the compound nucleus on the shell correction to the fission barrier and the dissipative effects influence
the fission-evaporation competition in order to obtain the residue nuclei from the superheavy nucleus formation. We also calculate
the τ
n
/τtot ratio at each step of the de-excitation cascade of the compound nucleus and we present a systematics of τ
n
/τtot (at first step of the cascade) for many reactions that lead to nuclei with Z=102–114. 相似文献
97.
P. M. Milazzo G. Vannini M. Bruno N. Colonna M. D’Agostino F. Gramegna G. V. Margagliotti P. F. Mastinu A. Moroni 《The European Physical Journal A - Hadrons and Nuclei》2000,7(3):355-360
The dependence of the nuclear temperatures of highly excited systems, extracted by means of the double ratios of the emitted
isotopes, on the experimental conditions is investigated. Experimental data obtained in the Xe+Cu 30 MeV/nucleon reaction
are used to study the sensitivity of the method and the effects of the energy thresholds on the obtained temperature values.
We find that the temperatures extracted using the He/Li ratios can be strongly influenced by the experimental energy thresholds
which are different for different elements. These distortions depend on the velocity of the emitting system and on the detection
angle and therefore particular care is needed in the choice of the detectors in those experiments in which velocities are
low and angles are large. The use of four isotopes of the same element make negligible such effects.
Received: 6 October 1999 / Accepted: 28 May 2000 相似文献
98.
Silvia Pianezze Luana Bontempo Matteo Perini Agostino Tonon Luca Ziller Pietro Franceschi Federica Camin 《Journal of mass spectrometry : JMS》2020,55(7)
Casein δ34S of 725 samples of cheese from all over the world were measured using IRMS. δ34S alone made it possible to establish characteristic ranges of values for two types of Italian cheese (Grana Padano PDO and Parmigiano Reggiano PDO) and for the different regions and provinces of both the Grana Padano PDO and the Parmigiano Reggiano PDO zones. Moreover, δ34S of PDO Italian samples were compared to both Italian (not PDO) and foreign competitive cheese samples. In all the cases, sulfur isotopic ratio analysis was a powerful tool to fix characteristic ranges of values for cheeses coming from different countries and to improve the information given by other isotopic parameters. 相似文献
99.
100.
D’Agostino G. Di Luzio M. Sharp N. E. Oddone M. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):411-419
Journal of Radioanalytical and Nuclear Chemistry - Following significant discrepancies observed when decay-correcting 122Sb γ-peak count rates to a reference time, we looked at the literature... 相似文献