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71.
Quantitative model of price diffusion and market friction based on trading as a mechanistic random process 总被引:1,自引:0,他引:1
We model trading and price formation in a market under the assumption that order arrival and cancellations are Poisson random processes. This model makes testable predictions for the most basic properties of markets, such as the diffusion rate of prices (which is the standard measure of financial risk) and the spread and price impact functions (which are the main determinants of transaction cost). Guided by dimensional analysis, simulation, and mean-field theory, we find scaling relations in terms of order flow rates. We show that even under completely random order flow the need to store supply and demand to facilitate trading induces anomalous diffusion and temporal structure in prices. 相似文献
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Michele Conti Michele Marconi Giulia Campanile Alessandro Reali Daniele Adami Raffaella Berchiolli Ferdinando Auricchio 《Meccanica》2017,52(3):633-644
Nitinol self-expanding stents are used for the endovascular management of peripheral artery diseases of the popliteal artery, which is located behind the knee joint. Unfortunately, the complex kinematics of the artery during the leg flexion leads to severe loading conditions, favouring the mechanical failure of the stent, calling for a specific biomechanical analysis. For this reason, in the present study we reconstruct by medical image analysis the patient-specific popliteal kinematics during leg flexion, which is subsequently exploited to compute the mechanical response of a stent model, virtually implanted in the artery by structural finite element analysis (FEA). The medical image analysis indicates a non-uniform configuration change of the artery during the leg flexion, leading to an increase of the vessel curvature above the knee. The computed mechanical response of the stent reflects the non-uniform configuration change of the artery as after the flexion the average stress is higher in the part of the stent located above the knee. Although the proposed analysis is limited to a case-study, it shows the capability of patient-specific FEA simulations to compute the mechanical response of a stent model subjected to the complex and severe loading conditions of the popliteal artery during leg flexion. 相似文献
74.
Pietro Baraldi Gian Carlo Franchini Andrea Marchetti Gavino Sanna Lorenzo Tassi Alessandro Ulrici Giulia Vaccari 《Journal of solution chemistry》2000,29(5):489-504
Thermodynamic interactions in the ethane-1,2-diol (1) + 1,2-dimethoxyethane(2) + water (3) ternary system have been investigated in terms of the excessmolar volume, derived from density measurements at 19 different temperaturesfrom –10;dg to 80;dgC. Fourteen three-component mixtures have been considered,covering the entire composition range. The excess molar volumes are discussedin terms of conformational changes induced in each component by the presenceof another one. The results obtained support the hypothesis of the absence of anythree-component complex adducts under all experimental conditions investigated. 相似文献
75.
Summary A method for interpolating between the (F)HNC and (F)PY approaches in order to take into account elementary contributions
has been presented in two preceding papers concerned with the properties of zero-temperature quantum fluids, described by
short-range correlated wave functions. In the present paper, both for Bose and for Fermi systems, the technique is extended
to the case in which the two-body radial distribution function contains a long-range tail, going asr
−4. The results obtained for the energy per particle and momentum distribution of liquid4He, polarized hydrogen and3He are presented in correspondence to variational wave functions containing only two-particle correlations.
Riassunto In due precedenti lavori è stata sviluppata una tecnica di interpolazione tra le approssimazioni (F)HNC e (F)PY per tenere conto dei cosiddetti contributi elementari nel calcolo delle proprietà dei fluidi quantistici a temperatura zero e descritti da funzioni d’onda con fattori di correlazione a corto raggio. Nel presente lavoro il metodo è esteso, per sistemi sia bosonici che fermionici, al caso in cui la funzione radiale di distribuzione contenga una coda con andamentor −4. Sono presentati i risultati ottenuti per l’energia per particella e la distribuzione di quantità di moto dell’4He liquido, dell’idrogeno polarizzato e dell’3He liquido, in corrispondenza a funzioni d’onda variazionali contenenti solo correlazioni di coppia.
Резюме В двух предыдущих работах был предложен метод интерполяции между (F)HNC и (F)PY подходами. В этих работах рассматривались свойства квантовых жидкостей при нулевой температуре, которые описываются волновыми функциями с короткодействующими корреляциями. В данной работе, для Бозеи Ферми-систем, предложенная тенхика обобщается на случай, когда двух-частичная радиальная функция распределения содержит длиннодействующий хвост, который спадает какr −4. Приводятся результаты для энергии на одну частицу и импульсное распределение для жидкого4He, поляризованного водорода и3H, причем соответствующие вариационные волновые функции содержат только двух-частичные корреляции.相似文献
76.
V. Cucinotta Alessandro Giuffrida Giulia Grasso Giuseppe Maccarrone Antonino Mazzaglia Graziella Vecchio 《Analytical and bioanalytical chemistry》2001,370(4):363-366
The separation of three pairs of enantiomeric herbicides has been successfully achieved by capillary electrophoresis at two different pH values in the presence of cyclodextrin derivatives previously synthesized in our laboratory. Two of these derivatives constitute a new class of receptor, the hemispherodextrins, in which a trehalose capping moiety is bonded to β-cyclodextrin. Because of their peculiar structure hemispherodextrins have very promising characteristics and the low receptor concentration required to achieve separation deserves particular interest. 相似文献
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79.
Elisa Barea Dr. Giulia Tagliabue Wen‐Guo Wang Dr. Manuel Pérez‐Mendoza Dr. Laura Mendez‐Liñan Francisco J. López‐Garzon Prof. Simona Galli Dr. Norberto Masciocchi Prof. Jorge A. R. Navarro Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(3):931-937
The novel coordination polymers [Cu(Hoxonic)(H2O)]n ( 1 ) and [Cu(Hoxonic)(bpy)0.5]n ? 1.5 n H2O ( 2?H2O ) (H3oxonic: 4,6‐dihydroxy‐1,3,5‐triazine‐2‐carboxylic acid; bpy: 4,4′‐bipyridine) have been isolated and structurally characterised by ab initio X‐ray powder diffraction. The dense phase 1 contains 1D zig‐zag chains in which Hoxonic dianions bridge square‐pyramidal copper(II) ions, apically coordinated by water molecules. On the contrary, 2?H2O , prepared by solution and solventless methods, is based on 2D layers of octahedral copper(II) ions bridged by Hoxonic ligands, further pillared by bpy spacers. The resulting pro‐porous 3D network possesses small hydrated cavities. The reactivity, thermal, magnetic and adsorptive properties of these materials have been investigated. Notably, the adsorption studies on 2 show that this material possesses unusual adsorption behaviour. Indeed, guest uptake is facilitated by increasing the thermal energy of both the guest and the framework. Thus, neither N2 at 77 K nor CO2 at 195 K are incorporated, and CH4 is only minimally adsorbed at 273 K and high pressures (0.5 mmol g?1 at 2500 kPa). By contrast, CO2 is readily incorporated at 273 K (up to 2.5 mmol g?1 at 2500 kPa). The selectivity of 2 towards CO2 over CH4 has been investigated by means of variable‐temperature zero coverage adsorption experiments and measurement of breakthrough curves of CO2/CH4 mixtures. The results show the highly selective incorporation of CO2 in 2 , which can be rationalised on the basis of the framework flexibility and polar nature of its voids. 相似文献
80.
Gabriella Santoni Dr. Miriam Mba Dr. Marcella Bonchio Dr. William A. Nugent Cristiano Zonta Dr. Giulia Licini Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(2):645-654
The stereoselective oxidation of differently functionalised benzyl phenyl sulfides has been examined by using enantiopure TiIV trialkanolamine complexes. These complexes efficiently catalyse the sulfoxidation with good stereoselectivities. The data highlight the contribution to the stereoselectivity of steric effects and non‐covalent π–π interactions between the aromatic rings of the TiIV complex and those pertaining to the substrates. Enantiomeric excesses have been correlated with the electrostatic potential surfaces (EPS) of the reacting sulfides. The overall study leads to a mechanistic interpretation that explains the stereoselectivity of the system and dissects the role of aromatic and steric interactions in the stereoselective process. 相似文献