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941.
942.
943.
Norman D. Hogikyan Walter P. Wodchis Constance Spak Paul R. Kileny 《Journal of voice》2001,15(4):576-586
Adductory spasmodic dysphonia is a focal dystonia of laryngeal muscles. Patients with this disorder typically have severe vocal difficulties, with significant functional, social, and emotional consequences. There is no widely accepted cure for this condition, however, botulinum toxin injections of the thyroarytenoid muscles are considered by most voice clinicians to be the state of the art treatment. Based on extensive experience treating patients for adductory spasmodic dysphonia, we feel that traditional means of voice assessment do not adequately measure either the disease severity or the treatment outcomes. That is, listening to or acoustically analyzing limited phonatory samples does not capture the functional, social, and emotional consequences of this disorder. These consequences will be reflected in a patient's voice-related quality of life (V-RQOL). Using a validated voice outcomes instrument, the V-RQOL Measure, the purpose of this study was to quantify longitudinal changes in the V-RQOL of patients with adductory spasmodic dysphonia who are undergoing botulinum toxin injections. Twenty-seven consecutive new patients presenting with dysphonia to our institution during an 18-month period were diagnosed with adductory spasmodic dysphonia, and treated patients were evaluated prospectively using the V-RQOL Measure. Results indicated that (1) V-RQOL was initially very low for these patients, (2) botulinum toxin injections improved it significantly for each injection cycle studied, and (3) the magnitude of the treatment effect appears to change across injections. 相似文献
944.
Marc Morant-Giner Isaac Brotons-Alcázar Nikita Y. Shmelev Dr. Artem L. Gushchin Luke T. Norman Prof. Andrei N. Khlobystov Dr. Antonio Alberola Dr. Sergio Tatay Dr. Josep Canet-Ferrer Dr. Alicia Forment-Aliaga Prof. Eugenio Coronado 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6670-6678
The preparation of 2D stacked layers combining flakes of different nature gives rise to countless numbers of heterostructures where new band alignments, defined at the interfaces, control the electronic properties of the system. Among the large family of 2D/2D heterostructures, the one formed by the combination of the most common semiconducting transition metal dichalcogenides, WS2/MoS2, has awakened great interest owing to its photovoltaic and photoelectrochemical properties. Solution as well as dry physical methods have been developed to optimize the synthesis of these heterostructures. Here, a suspension of negatively charged MoS2 flakes is mixed with a methanolic solution of a cationic W3S4-core cluster, giving rise to a homogeneous distribution of the clusters over the layers. In a second step, a calcination of this molecular/2D heterostructure under N2 leads to the formation of clean WS2/MoS2 heterostructures, where the photoluminescence of both counterparts is quenched, proving an efficient interlayer coupling. Thus, this chemical method combines the advantages of a solution approach (simple, scalable, and low-cost) with the good quality interfaces reached by using more complicated traditional physical methods. 相似文献
945.
946.
We introduce a class SN of matrices whose elements are terms of convolutions of binomial functions of complex numbers. A multiplication theorem is proved for elements of SN. The multiplication theorem establishes a homomorphism of the group of 2 by 2 nonsingular matrices with complex elements into a group GN contained in SN. As a direct consequence of representation theory, we also present related spectral representations for special members of GN. We show that a subset of GN constitutes the system of Krawtchouk matrices, which extends published results for the symmetric case. 相似文献
947.
Rebecca Notis Dardashti Dr. Shailesh Kumar Dr. Shawn M. Sternisha Dr. Post Sai Reddy Prof. Brian G. Miller Prof. Norman Metanis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(22):4952-4957
Despite their biological importance, post-translationally modified proteins are notoriously difficult to produce in a homogeneous fashion by using conventional expression systems. Chemical protein synthesis or semisynthesis offers a solution to this problem; however, traditional strategies often rely on sulfur-based chemistry that is incompatible with the presence of any cysteine residues in the target protein. To overcome these limitations, we present the design and synthesis of γ-selenolysine, a selenol-containing form of the commonly modified proteinogenic amino acid, lysine. The utility of γ-selenolysine is demonstrated with the traceless ligation of the small ubiquitin-like modifier protein, SUMO-1, to a peptide segment of human glucokinase. The resulting polypeptide is poised for native chemical ligation and chemoselective deselenization in the presence of unprotected cysteine residues. Selenolysine's straightforward synthesis and incorporation into synthetic peptides marks it as a universal handle for conjugating any ubiquitin-like modifying protein to its target. 相似文献
948.
JETP Letters - Semimetal states of crystalline molecular hydrogen have been obtained at a temperature of 100 K in the pressure range from 410 to 626 GPa. To analyze the nature of conductivity, the... 相似文献
949.
Frida C. D. Dimarco Palencia Vanesa A. Muñoz Ariana C. Posadaz Diego A. Cifuente Sandra Miskoski Gabriela V. Ferrari Norman A. García María P. Montaña 《Photochemistry and photobiology》2020,96(5):1005-1013
Essential oils are a mixture of volatile compounds, products of the secondary metabolism of plants. Once extracted, they can be deteriorated losing their organoleptic and therapeutic properties due to various environmental factors, being light exposure in aerobic conditions the main cause. In this work, the oregano essential oil extraction and characterization from Origanum vulgare plants grown in the experimental field of the FTU-UNSL and its photodegradation in MeOH:H2O 60:40 v/v solvent were studied. Characterization by EIMS and NIST Mass Spectrometry indicates the main compounds of oregano essential oil, quantified in the extracted oil by GC-MS, are carvacrol (7.14%) and thymol (47.37%). Degradation of essential oil and its two major components can be caused by reactive oxygen species photogenerated from endogenous sensitizers as riboflavin. Our results suggest degradation occurs involving singlet molecular oxygen. Interaction of carvacrol and thymol with singlet oxygen is mainly a physical process, while essential oil has an important reactive component, which indicates there might be other constituents which could contribute to reactive photoprotection. The effect of simultaneous presence of oregano essential oil and tryptophan amino acid—used as a photooxidizable model under riboflavin-photosensitizing conditions—was studied in order to evaluate the possible photoprotection exerted by the essential oil. 相似文献
950.
ABSTRACTVibrational spectroscopy of tolane (diphenylacetylene), which has 66 normal modes, has been advanced. Anharmonic wavenumber predictions were made with the quartic potential energy surface obtained with B3LYP/cc-pVTZ model and the second-order perturbation theory (VPT2). Infrared (IR) intensity and Raman activities were computed at the harmonic level. The IR spectrum of the crystal and Raman spectra of the liquid and the crystal tolane were newly recorded. The lingering problem of an excess of polarised Raman bands at wavenumbers appropriate for fundamentals, other than ag modes, has now been attributed to Coriolis coupling within modes of g symmetry species. Consequently, D2h point symmetry group has been confirmed for a planar tolane molecule. Assignments for almost all fundamentals of tolane are now secure. The assignment for ν32 remains questionable. Remaining unassigned fundamentals are: ν34 and ν35, which, as au symmetry species, are IR- and Raman-inactive transitions, and ν59(b2u), which is predicted to have a very low wavenumber. 相似文献