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91.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Aoki K Aphecetche L Armendariz R Aronson SH Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bazilevsky A Belikov S Bennett R Berdnikov Y Bickley AA Boissevain JG Borel H Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Campbell S Chang BS Charvet JL Chernichenko S Chiba J Chi CY Chiu M Choi IJ Chujo T Chung P 《Physical review letters》2007,98(23):232002
J/psi production in p+p collisions at square root s=200 GeV has been measured by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider over a rapidity range of -2.2相似文献
92.
Summary Pressurised solvent extraction was applied to the extraction of three withanolides from the leaves oflochroma gesnerioides. A study was carried out of the influence of various parameters on the extraction efficiency and kinetic parameters; these
included the nature of the extracting solvent, its flow rate, the pressure and temperature, as well as the particle size of
the plant material. The pressurised solvent extraction method compared to a conventional Soxhlet extraction showed similar
recoveries and extraction selectivity but the total handling time and solvent volume were dramatically reduced. 相似文献
93.
94.
J-L. Waldspurger 《Inventiones Mathematicae》1978,50(2):135-168
Sans résumé 相似文献
95.
Rubiolo P Liberto E Sgorbini B Russo R Veuthey JL Bicchi C 《Journal of separation science》2008,31(6-7):1074-1084
This study reports on the compatibility of a conventional quadrupole MS (qMS) as detector for Fast-GC in terms of separation, identification, and quantitation when applied to the analysis of peppermint essential oil (e.o.), adopted as representative of this field. The influence of Fast-GC carried out on a 10 mx0.1 mm id narrow bore column with temperature programmes from 20 to 60 degrees C/min on the results of a qMS in total ion chromatograms (TIC) at different speeds (from 999 and 11 111 amu/s) and SIM modes was evaluated on ten differently abundant components characterizing peppermint e.o. Separation measure (S), peak capacity (n), and half height peak width were taken as separation parameters; match quality, number of scans per peak (NP), spectral skewing, and TIC area repeatability were used for identification. Quantitation was in SIM mode and NP, dwell time, SIM area repeatability and calibration curves, LOD, and LOQ of the selected components were measured. The results show that the peppermint e.o. markers can successfully be analysed qualitatively and quantitatively by F-GC-qMS up to temperature programmes of 60 degrees /min provided that a suitable scan speed is applied. Fast-GC-qMS reduces analysis time by a factor greater than ten and gives results that are qualitatively reliable and quantitatively comparable to those obtained by conventional GC-qMS. 相似文献
96.
Two phenomenological approaches are currently used in the study of the vitreous state. One is based on the concept of fictive temperature introduced by Tool [J. Res. Natl. Bur. Stand. 34, 199 (1945)] and recently revisited by Nieuwenhuizen [Phys. Rev. Lett. 80, 5580 (1998)]. The other is based on the thermodynamics of irreversible processes initiated by De Donder at the beginning of the last century [L'Affinite (Gauthier-Villars, Paris, 1927)] and recently used by Moller et al. for a thorough study of the glass transition [J. Chem. Phys. 125, 094505 (2006)]. This latter approach leads to the possibility of describing the glass transition by means of the freezing-in of one or more order parameters connected to the internal structural degrees of freedom involved in the vitrification process. In this paper, the equivalence of the two preceding approaches is demonstrated, not only for glasses but in a very general way for any system undergoing an irreversible transformation. This equivalence allows the definition of an effective temperature for all systems departed from equilibrium generating a positive amount of entropy. In fact, the initial fictive temperature concept of Tool leads to the generalization of the notion of temperature for systems out of thermodynamic equilibrium, for which glasses are just particular cases. 相似文献
97.
Schiller A Frank N Baumann T Bazin D Brown BA Brown J DeYoung PA Finck JE Gade A Hinnefeld J Howes R Lecouey JL Luther B Peters WA Scheit H Thoennessen M Tostevin JA 《Physical review letters》2007,99(11):112501
We have observed a resonance in neutron-fragment coincidence measurements that is presumably the first excited state of 23O at 2.8(1) MeV excitation energy which decays into the ground state of 22O. This interpretation is consistent with theory. The reaction mechanism supports the assignment of the observed state as the 5/2+ hole state. This assignment and the recently observed 3/2+ particle state advance the understanding of 23O. 相似文献
98.
B. Debrus J. Broséus D. Guillarme P. Lebrun P. Hubert J.-L. Veuthey P. Esseiva S. Rudaz 《Analytical and bioanalytical chemistry》2011,399(8):2719-2730
Nowadays, in forensic laboratories, heroin profiling is frequently carried out by gas chromatography coupled with mass spectrometry
(GC-MS). This analytical technique is well established, provides good sensitivity and reproducibility, and allows the use
of large databases. Despite those benefits, recently introduced analytical techniques, such as ultra-high-pressure liquid
chromatography (UHPLC), could offer better chromatographic performance, which needs to be considered to increase the analysis
throughput for heroin profiling. With the latter, chromatographic conditions were optimized through commercial modeling software
and two atmospheric pressure ionization sources were evaluated. Data obtained from UHPLC–MS/MS were thus transferred, thanks
to mathematical models to mimic GC-MS data. A calibration and a validation set of representative heroin samples were selected
among the database to establish a transfer methodology and assess the models’ abilities to transfer using principal component
analysis and hierarchical classification analysis. These abilities were evaluated by computing the frequency of successful
classification of UHPLC–MS/MS data among GC-MS database. Seven mathematical models were tested to adjust UHPLC–MS/MS data
to GC-MS data. A simplified mathematical model was finally selected and offered a frequency of successful transfer equal to
95%. 相似文献
99.
Iadecola A Joseph B Puri A Simonelli L Mizuguchi Y Testemale D Proux O Hazemann JL Takano Y Saini NL 《J Phys Condens Matter》2011,23(42):425701
The local structure of Fe(Se, S)(1-x)Te(x) ternary (11-type) chalcogenides has been studied by temperature dependent Fe K-edge extended x-ray absorption fine structure measurements. We find that the Fe-Se and Fe-Te distances in ternary FeSe(1-x)Te(x) are closer to the respective distances in the binary systems, revealing significant divergence of the local structure from the average one. The mean square relative displacements show a systematic change with Te content, consistent with bond relaxation in the inhomogeneous ternary phases. Also, the Fe-Te and Fe-S distances in the FeS(0.2)Te(0.8) ternary system are found to be different in the crystallographically homogeneous structure. The observed features are characteristic of ternary random alloys, suggesting that a proper consideration should be given to the atomic distribution for describing the complex electronic structure of these multi-band Fe-based chalcogenides. 相似文献
100.
This work describes the use of layered double hydroxides (LDHs) for the immobilisation of acetylcholinesterase (AChE) on insulator/semiconductor solid supports. Different LDHs have been synthesised by a co-precipitation method. Afterwards, biohybrid materials based on AChE-LDH mixtures have been produced using wild and recombinant enzymes. Spectroscopic techniques have confirmed the LDH phase identity and the links created between the LDH and AChE. Spectrophotometric assays have demonstrated that most of the biohybrid materials are functional and stable. Several configurations have been used for AChE immobilisation. The highest catalytic responses have been observed when using wild enzyme and immobilising AChE-LDH mixtures on LDHs previously deposited on the solid supports. LDHs have been demonstrated to be suitable host matrices for AChE immobilisation on electrodes for the subsequent development of electrochemical biosensors. 相似文献