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91.
Mathieu Cianfarani Jean-Martin Paoli Jean-Christophe Tomasi 《Archiv der Mathematik》2011,96(3):253-262
Let \({\mathcal{L}(X)}\) be the algebra of all bounded operators on a Banach space X. \({\theta:G\rightarrow \mathcal{L}(X)}\) denotes a strongly continuous representation of a topological abelian group G on X. Set \({\sigma^1(\theta(g)):=\{\lambda/|\lambda|,\lambda\in\sigma(\theta(g))\}}\), where σ(θ(g)) is the spectrum of θ(g) and \({\Sigma:=\{g\in G/\enskip\text{there is no} \enskip P\in \mathcal{P}/P\subseteq \sigma^1(\theta(g))\}}\), where \({\mathcal{P}}\) is the set of regular polygons of \({\mathbb{T}}\) (we call polygon in \({\mathbb{T}}\) the image by a rotation of a closed subgroup of \({\mathbb{T}}\), the unit circle of \({\mathbb{C}}\)). We prove here that if G is a locally compact and second countable abelian group, then θ is uniformly continuous if and only if Σ is non-meager. 相似文献
92.
93.
Dr. Luca Conti Prof. Andrea Bencini Prof. Camilla Ferrante Dr. Cristina Gellini Prof. Paolo Paoli Dr. Matteo Parri Prof. Giangaetano Pietraperzia Prof. Barbara Valtancoli Prof. Claudia Giorgi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(45):10606-10615
A comparative study between two novel, highly water soluble, ruthenium(II) polypyridyl complexes, [Ru(phen)2 L ′] and [Ru(phen)2Cu(II) L ′] ( L and L -CuII), containing the polyaazamacrocyclic unit 4,4′-(2,5,8,11,14-pentaaza[15])-2,2′-bipyridilophane ( L ′), is herein reported. L and L -CuII interact with calf-thymus DNA and efficiently cleave DNA plasmid when light-activated. They also possess great penetration abilities and photo-induced biological activities, evaluated on an A375 human melanoma cell line, with L -CuII being the most effective. Our study highlights the key role of the Fenton active CuII center within the macrocycle framework, that would play a synergistic role with light activation in the formation of cytotoxic ROS species. Based on these results, an optimal design of RuII polypyridyl systems featuring specific CuII-chelating polyamine units could represent a suitable strategy for the development of novel and effective photosensitizers in photodynamic therapy. 相似文献
94.
L. Paoli 《Archive for Rational Mechanics and Analysis》2010,198(2):457-503
We consider a discrete mechanical system with a non-trivial mass matrix, subjected to perfect unilateral constraints described by the geometrical inequalities ${f_{\alpha} (q) \geqq 0, \alpha \in \{1, \dots, \nu\} (\nu \geqq 1)}$ . We assume that the transmission of the velocities at impact is governed by Newton’s Law with a coefficient of restitution e = 0 (so that the impact is inelastic). We propose a time-discretization of the second order differential inclusion describing the dynamics, which generalizes the scheme proposed in Paoli (J Differ Equ 211:247–281, 2005) and, for any admissible data, we prove the convergence of approximate motions to a solution of the initial-value problem. 相似文献
95.
This note deals with three-dimensional models for rate-independent processes describing materials undergoing phase transformations with heat transfer. The problem is formulated within the framework of generalized standard solids by the coupling of the momentum equilibrium equation and the flow rule with the heat transfer equation. The existence of a global solution for this thermodynamically consistent problem is obtained by using a fixed-point argument combined with global energy estimates. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
96.
Stephan R. Rakotonandrasana Delphin J. R. Rabehaja Mathieu Paoli Charles Andrianjara Ange Bighelli 《Natural product research》2019,33(8):1200-1203
The chemical composition of twenty-five essential oil samples from the aerial parts of two Malagasy endemic species Billburttia capensoides Sales & Hedge and B. vaginoides Sales & Hedge, were investigated for the first time. Based on chromatographic profiles, three selected samples were investigated using GC(RI), GC-MS and 13C NMR. The content of the main components varied drastically from sample to sample: p-mentha-1,3,8-triene (0.2–52.7%), terpinolene (2.8–40.7%) and dill apiole (0.0–22.2%). Statistical analysis of the 25 oil compositions allowed the distinction of two well-differentiated groups. Samples of group I contained mainly p-mentha-1,3,8-triene while the Group II was dominated by terpinolene and dill apiole. 相似文献
97.
Patrizia Rossi Paola Paoli Andrea Ienco Diletta Biagi Maurizio Valleri Luca Conti 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):783-792
Dexketoprofen [(2S)‐2‐(3‐benzoylphenyl)propanoic acid], C16H14O3, is the S‐enantiomer of ketoprofen, a nonsteroidal anti‐inflammatory drug (NSAID) that has analgesic, antipyretic and anti‐inflammatory properties, and finds applications for the short‐term treatment of mild to moderate pain. A new crystalline phase of dexketoprofen is reported. Its solid‐state structure was determined by single‐crystal X‐ray diffraction (SCXRD). The molecular structure of the two independent molecules found in the asymmetric unit of this new phase ( DXKP‐β ) were compared to those of the already known crystal form of dexketoprofen ( DXKP‐α ) and with the S‐enantiomer of the racemic compound. The three different conformers of dexketoprofen found in DXKP‐α and DXKP‐β were then investigated by computational methods. The optimized structures are very close to the corresponding starting geometries and do not differ significantly in energy. The crystal packing of DXKP‐β was studied by means of Hirshfeld surface (HS) analysis; interaction energies were also calculated. A comparison with DXKP‐α shows close similarities between the two crystal forms, i.e. in both cases, molecules assemble through the catemer O—H…O synthon of the carboxylic acid stabilized by additional C—H…O contacts and, accordingly, the interaction energies, as well as the contributions to the HS area, are very similar. Finally, the thermal behaviour of the two polymorphs of dexketoprofen was assessed by means of XRD (both from single crystal and microcrystalline powder) and differential scanning calorimetry (DSC); both crystal forms are stable under the experimental conditions adopted (air, 300–350 K for DXKP‐α and 300–340 K DXKP‐β ) and no solid–solid phase transition occurs between the two crystal forms in the investigated temperature range (from 100 K up to ca 350 K). 相似文献
98.
Patrizia Rossi Paola Paoli Laura Chelazzi Luca Conti Andrea Bencini 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(2):87-96
Metoprolol {systematic name: (RS)‐1‐isopropylamino‐3‐[4‐(2‐methoxyethyl)phenoxy]propan‐2‐ol}, C15H25NO3, is a cardioselective β1‐adrenergic blocking agent that shares part of its molecular skeleton with a large number of other β‐blockers. Results from its solid‐state characterization by single‐crystal and variable‐temperature powder X‐ray diffraction and differential scanning calorimetry are presented. Its molecular and crystal arrangements have been further investigated by molecular modelling, by a Cambridge Structural Database (CSD) survey and by Hirshfeld surface analysis. In the crystal, the side arm bearing the isopropyl group, which is common to other β‐blockers, adopts an all‐trans conformation, which is the most stable arrangement from modelling data. The crystal packing of metoprolol is dominated by an O—H…N/N…H—O pair of hydrogen bonds (as also confirmed by a Hirshfeld surface analysis), which gives rise to chains containing alternating R and S metoprolol molecules extending along the b axis, supplemented by a weaker O…H—N/N—H…O pair of interactions. In addition, within the same stack of molecules, a C—H…O contact, partially oriented along the b and c axes, links homochiral molecules. Amongst the solid‐state structures of molecules structurally related to metoprolol deposited in the CSD, the β‐blocker drug betaxolol shows the closest analogy in terms of three‐dimensional arrangement and interactions. Notwithstanding their close similarity, the crystal lattices of the two drugs respond differently on increasing temperature: metoprolol expands anisotropically, while for betaxolol, an isotropic thermal expansion is observed. 相似文献
99.
V.C. Fuertes M.C. Blanco D.G. Franco J.M. De Paoli E.V. Pannunzio Miner R.D. Snchez M.T. Fernndez-Díaz R.E. Carbonio 《Physica B: Condensed Matter》2009,404(18):2717-2719
The new double perovskite La3Co2TaO9 has been prepared by a solid-state procedure. The crystal and magnetic structures have been studied from X-ray powder diffraction (XRPD) and neutron powder diffraction (NPD) data. Rietveld refinements were performed in the monoclinic space group P21/n. The structure consists of an ordered array of alternating B′O6 and B″O6 octahedra sharing corners, tilted along the three pseudocubic axes according to the Glazer notation a−b−c+. Rietveld refinements show that at RT the cell parameters are a=5.6005(7) Å, b=5.6931(7) Å, c=7.9429(9) Å and β=89.9539(7)°, and the refined crystallographic formula of this “double perovskite” can be written as La2(Co)2d(Co1/3Ta2/3)2cO6. Magnetization measurements and low-temperature NPD data show that the perovskite is a ferromagnet with TC=72 K. At high T it follows the Curie–Weiss law with an effective magnetic moment of 3.82μB per Co ion which is very close to spin only Co2+ (HS). 相似文献
100.
Diabetes mellitus (DM) represents a group of metabolic disorders that leads to acute and long-term serious complications and is considered a worldwide sanitary emergence. Type 2 diabetes (T2D) represents about 90% of all cases of diabetes, and even if several drugs are actually available for its treatment, in the long term, they show limited effectiveness. Most traditional drugs are designed to act on a specific biological target, but the complexity of the current pathologies has demonstrated that molecules hitting more than one target may be safer and more effective. The purpose of this review is to shed light on the natural compounds known as α-glucosidase and Protein Tyrosine Phosphatase 1B (PTP1B) dual-inhibitors that could be used as lead compounds to generate new multitarget antidiabetic drugs for treatment of T2D. 相似文献