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291.
292.
Franco Salmistraro Roberto Catenacci Annalisa Marzuoli 《General Relativity and Gravitation》1981,13(5):425-432
We consider the Killing-Yano equation by dropping the antisymmetry hypothesis and studying some consequences of the integrability conditions. We find that the cases of interest are more general, and we discuss the relevance of solutions to the construction of Killing tensors. 相似文献
293.
294.
Grimaldi A Banfi S Vizioli J Tettamanti G Noonan DM de Eguileor M 《Macromolecular bioscience》2011,11(8):1008-1019
The biopolymer matrigel loaded with cytokine can be used for the recruitment in vivo of specific cell populations and as a vector for the preparation of cell cultures. Data demonstrate that the injection of the matrigel biopolymer supplemented with interleukin-8 (IL-8) in the leech Hirudo medicinalis can be used to purify cell populations showing the same morphofunctional and molecular mechanisms of specific populations of vertebrate hematopoietic precursor cells involved in tissue repair. These cells spontaneously differentiated into myofibroblasts. This approach highlights how the innovative use of a cytokine-loaded biopolymer for an in vivo cell sorting method, applied to a simple invertebrate model, can be a tool for studying myofibroblast cell biology and its regulation, step by step. 相似文献
295.
Luisa Pasti Elena Sarti Alberto Cavazzini Nicola Marchetti Francesco Dondi Annalisa Martucci 《Journal of separation science》2013,36(9-10):1604-1611
The adsorption behaviour of three commonly used drugs, namely ketoprofen, hydrochlorothiazide and atenolol, from diluted aqueous solutions on beta zeolites with different SiO2/Al2O3 ratio (i.e. 25, 38 and 360) was investigated by changing the ionic strength and the pH, before and after thermal treatment of the adsorbents. The selective adsorption of drugs was confirmed by thermogravimetry and X‐ray diffraction. The adsorption capacity of beta zeolites was strongly dependent on both the solution pH and the alumina content of the adsorbent. Such a remarkable difference was interpreted as a function of the interactions between drug molecules and zeolite surface functional groups. Atenolol was readily adsorbed on the less hydrophobic zeolite, under pH conditions in which electrostatic interactions were predominant. On the other hand, ketoprofen adsorption was mainly driven by hydrophobic interactions. For undissociated molecules the adsorption capability increased with the increase of hydrophobicity. 相似文献
296.
Annalisa La Gatta Chiara Schiraldi Agata PapaMario De Rosa 《Polymer Degradation and Stability》2011,96(4):630-636
The cosmetic market for hyaluronic acid (HA)-based dermal fillers is in continuous and rapid growth and, simultaneously, the development of more effective and safer products is strongly intensifying. In order to highlight the differences among the currently available fillers, in terms of their physical characteristics and on the relation of such properties with product effectiveness, an in vitro evaluation of eight marketed HA-based gels was performed.Filler swelling properties, soluble HA fraction and rheological behaviour were investigated. Furthermore the relative stability to enzymatic hydrolysis was tested. The presence of soluble HA in the formulations varied from 7 ± 1(%) to 33 ± 5(%) with respect to the total HA concentration. Chromatographic analyses showed that the soluble fractions consist of low molecular weight chains (Mw: 260-480 kDa) presenting large distributions (Mw/Mn: 1.6-2.5). The investigated fillers were found to be non-equilibrium gels in their commercial formulation also showing different swelling capacities. Rheological measurements indicated a shear thinning behaviour for all the products and elastic modulus values varied over a wide range (100-1800 Pa). Fillers proved differently sensitive to enzymatic degradation. Swelling capacity and enzymatic stability were found consistently dependent on the total HA concentration, insoluble/soluble HA ratio and on the crosslinking extent. 相似文献
297.
Total Reflection X-ray Fluorescence (TXRF) is a well-established technique for chemical analysis, but it is mainly employed for quality control in the electronics semiconductor industry. The capability to analyze liquid and uniformly thin solid samples makes this technique suitable for other applications, and especially in the very critical field of environmental analysis. Comparison with standard methods like inductively coupled plasma (ICP) and atomic absorption spectroscopy (AAS) shows that TXRF is a practical, accurate, and reliable technique in occupational settings. Due to the greater sensitivity necessary in trace heavy metal detection, TXRF is also suitable for environmental chemical analysis. In this paper we show that based on appropriate standards, TXRF can be considered for non-destructive routine quantitative analysis of environmental matrices such as air filters. This work has been developed in the frame of the EU-FP6 PHIME (Public Health Impact of long-term, low-level Mixed element Exposure in susceptible population strata) Integrated Project (www.phime.org). The aim of this work was to investigate Mn air pollution in the area of Vallecamonica (Italy). 相似文献
298.
An atmospheric pressure plasma enhanced atomic layer deposition reactor has been developed, to deposit Al2O3 films from trimethyl aluminum and an He/O2 plasma. This technique can be used for 2D patterned deposition in a single in‐line process by making use of switched localized plasma sources. It was observed that the sharpness of the patterns is primarily influenced by the concentration of reactive plasma species and by the dimensions of the plasma source. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
299.
Annalisa Vigorito Camilla Calabrese Assimo Maris Donatella Loru Isabel Pea M. Eugenia Sanz Sonia Melandri 《Molecules (Basel, Switzerland)》2022,27(9)
Benzenesulfonamides are a class of molecules of extreme interest in the biochemical field because many of them are active against a variety of diseases. In this work, the pharmacophoric group benzensulfonamide, its derivatives para-toluensulfonamide and ortho-toluensulfonamide, and the bioactive molecule sulfanilamide, were investigated using rotational spectroscopy to determine their conformations and the influence of different substituents on their structures. For all species, the hyperfine structure due to the 14N atom was analyzed, and this provided crucial information for the unambiguous identification of the observed conformation of all molecules. In addition, for ortho-toluensulfonamide, the vibration–rotation hyperfine structure related to the methyl torsion was analyzed, and the methyl group rotation barrier was determined. For benzensulfonamide, partial rS and r0 structures were established from the experimental rotational constants of the parent and two deuterated isotopic species. In all compounds except ortho-toluensulfonamide, the amino group of the sulfonamide group lies perpendicular to the benzene plane with the aminic hydrogens eclipsing the oxygen atoms. In ortho-toluensulfonamide, where weak attractive interactions occur between the nitrogen lone pair and the methyl hydrogen atoms, the amino group lies in a gauche orientation, retaining the eclipsed configuration with respect to the SO2 frame. A comparison of the geometrical arrangements found in the PDB database allowed us to understand that the bioactive conformations are different from those found in isolated conditions. The conformations within the receptor are reached with an energy cost, which is balanced by the interactions established in the receptor. 相似文献
300.
Alexandre Chappard Dr. Craig Leighton Dr. Rebecca S. Saleeb Kiani Jeacock Dr. Sarah R. Ball Katie Morris Owen Kantelberg Dr. Ji-Eun Lee Dr. Elsa Zacco Prof. Dr. Annalisa Pastore Prof. Dr. Margaret Sunde Dr. David J. Clarke Dr. Patrick Downey Prof. Dr. Tilo Kunath Dr. Mathew H. Horrocks 《Angewandte Chemie (International ed. in English)》2023,62(15):e202216771
Protein misfolding and aggregation into oligomeric and fibrillar structures is a common feature of many neurogenerative disorders. Single-molecule techniques have enabled characterization of these lowly abundant, highly heterogeneous protein aggregates, previously inaccessible using ensemble averaging techniques. However, they usually rely on the use of recombinantly-expressed labeled protein, or on the addition of amyloid stains that are not protein-specific. To circumvent these challenges, we have made use of a high affinity antibody labeled with orthogonal fluorophores combined with fast-flow microfluidics and single-molecule confocal microscopy to specifically detect α-synuclein, the protein associated with Parkinson's disease. We used this approach to determine the number and size of α-synuclein aggregates down to picomolar concentrations in biologically relevant samples. 相似文献