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131.
Clara Argerich Martín Ruben Ibáñez Pinillo Anais Barasinski Francisco Chinesta 《Comptes Rendus Mecanique》2019,347(11):754-761
The aim of this paper is to present a new classification and regression algorithm based on Artificial Intelligence. The main feature of this algorithm, which will be called Code2Vect, is the nature of the data to treat: qualitative or quantitative and continuous or discrete. Contrary to other artificial intelligence techniques based on the “Big-Data,” this new approach will enable working with a reduced amount of data, within the so-called “Smart Data” paradigm. Moreover, the main purpose of this algorithm is to enable the representation of high-dimensional data and more specifically grouping and visualizing this data according to a given target. For that purpose, the data will be projected into a vectorial space equipped with an appropriate metric, able to group data according to their affinity (with respect to a given output of interest). Furthermore, another application of this algorithm lies on its prediction capability. As it occurs with most common data-mining techniques such as regression trees, by giving an input the output will be inferred, in this case considering the nature of the data formerly described. In order to illustrate its potentialities, two different applications will be addressed, one concerning the representation of high-dimensional and categorical data and another featuring the prediction capabilities of the algorithm. 相似文献
132.
Clara Burgos‐Simn Noemí García‐Medina David Martínez‐Rodríguez Rafael‐Jacinto Villanueva 《Mathematical Methods in the Applied Sciences》2019,42(17):5746-5757
Bladder cancer is one of the most common malignant diseases in the urinary system and a highly aggressive neoplasm. The prognosis is not favorable usually, and its evolution for particular patients is very difficult to find out. In this paper, we propose a dynamic mathematical model that describes the bladder tumor growth and the immune response evolution. This model is customized for a single patient, determining appropriate model parameter values via model calibration. Due to the uncertainty of the tumor evolution, using the calibrated model parameters, we predict the tumor size and the immune response evolution over the next few months assuming three different scenarios: favorable, neutral, and unfavorable. In the former, it is not expected any trace of the cancer in the middle of September 2018 (after 16 mo). In the neutral scenario, at the same date, a 7‐ to 8‐mm tumor is expected. In the worst case, a 40‐mm tumor is expected. The patient was cited on 10 September 2018 to check the tumor size, and according to the doctors, there was no sign of recurrence. It seems that we are in the favorable scenario. The patient will be called again for follow‐up in mid‐2019. 相似文献
133.
134.
We present some results whose central theme is the phenomenon of the first eigenvalue of the Laplacian and conductance of
the dynamical system. Our main tool is a method for studying how the hyperbolic metric on a Riemann surface behaves under
deformation of the surface. With this model, we show that there are variation of the first eigenvalue of the laplacian and
the conductance of the dynamical system, with the Fenchel–Nielsen coordinates, that characterize the surface. 相似文献
135.
Pedro W. Araujo Clara V. Gómez Eunice Marcano Zully Benzo 《Fresenius' Journal of Analytical Chemistry》1995,351(2-3):204-208
A multivariate study was applied to the investigation of the variables affecting the cadmium sensitivity in a graphite furnace, with and without platform atomization or matrix modifier. The results indicated that, depending on the atomization system used, the factors studied (drying, ashing, atomization, calibration curve) exert an influence on the analysis. The interactions between the factors were also analyzed. 相似文献
136.
The reaction of coumarin with the title nitrile oxide gives a single regioisomer in high yield. This result is compared with the dipolarophilic behavior of cinnamic acid esters. 相似文献
137.
Díaz Rizo Oscar Barrios Cossio Josiel González Hernández Patricia Suárez Muñoz Margaret D’Alessandro Rodríguez Katia Melián Rodríguez Clara M. Martínez-Villegas Nadia V. Badawy Wael Frontasieva Marina 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):1079-1087
Journal of Radioanalytical and Nuclear Chemistry - Peloids from some Cuban spas (San Diego, Elguea, Santa Lucía, Cajío and Colony) have been studied using Instrumental Neutron Activation... 相似文献
138.
Raikko Kiveks Miquel Angles Flores Clara Vias Reijo Sillanp 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o570-o571
In the title o‐carborane derivative, C9H18B10S, the methyl and phenylsulfanyl groups are connected to the C atoms of the carborane cage. The Ccage—Ccage distance is 1.708 (4) Å. 相似文献
139.
Andre Rosowsky Clara E. Mota Sherry F. Queener 《Journal of heterocyclic chemistry》1995,32(1):335-340
2,4-Diamino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidines with di- and trimethoxyaralkyl substitution at the 6-position were synthesized from the N6-unsubstituted compound and appropriate aralkyl bromides in N,N-dimethylformamide solution containing a catalytic amount of sodium iodide. An improved method of preparation of 2,4-diamino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine from 2-amino-6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one was also developed, in which N2 was protected by reaction with pivalic anhydride and the resulting product was subjected consecutively to reaction with 4-chlorophenylphosphorodichloridate and 1,2,4-triazole, ammonolysis to replace the 4-imidazolido group and remove the N2-pivaloyl group, and catalytic hydrogenolysis to remove the 6-benzyl group. In assays of the ability of the products to inhibit dihydrofolate reductase from Pneumocystis carinii, and Toxoplasma gondii, and rat liver the most active of the compounds tested was 2,4-diamino-6-(2′-bromo-3′,4′,5′-trimethoxybenzyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine. The concentration of this compound needed to inhibit enzyme activity by 50% was 0.51 μM against the P. carinii enzyme, 0.09 μM against the T. gondii enzyme, and 0.35 μM against the rat enzyme. Thus, there was selectivity of binding to T. gondii enzyme, but not P. carinii enzyme, relative to rat enzyme. 2′,5′-Dimethoxybenzyl analogues were less active than the corresponding 3′,4′,5′-trimethoxybenzyl analogues, and compounds with a CH2CH2 or CH2CH2CH2 bridge were less active than those with a CH2 bridge. 2,4-Diamino-6-(2′-bromo-3′,4′,5′-trimethoxybenzyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine showed greater selectivity than trimetrexate or piritrexim for the P. carinii and T. gondii enzyme, but was less selective than trimethoprim or pyrimethamine. However its molar potency against both enzymes was greater than that of trimethoprim, the antifolate most commonly used, in combination with sulfamethoxazole, for initial treatment of opportunistic P. carinii and T. gondii infections in patients with AIDS and other disorders of the immune system. 相似文献
140.
Viñas C Llop J Teixidor F Kivekäs R Sillanpää R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(6):1933-1941
Rotation about the centroid/metal/centroid axis in ferrocene is facile; the activation energy is 1-5 kcal mol(-1). The structurally similar sandwich complexes derived from closo-[3-Co(eta5-NC4H4)-1,2-C2B9H11] (1) have a different rotational habit. In 1, the cis rotamer in which the pyrrolyl nitrogen atom bisects the carboranyl cluster atoms is 3.5 kcal mol(-1) more stable in energy than the rotamer that is second lowest in energy. This cis rotamer is wide, spanning 216 degrees , and may be split into three rotamers of almost equal energy by substituting the N and the carboranyl carbon atoms adequately. To support this statement, closo-[3-Co(eta5-NC4H4)-1,2-(CH3)2-1,2-C2B9H9] (2), closo-[3-Co(eta5-NC4H4)-1,2-(mu-CH2)3-1,2-C2B9H9] 3, 2-->BF3, and 3-->BF3 have been prepared. Two rotamers are found at low temperature for 2-->BF(3) and 3-->BF3. Compounds 2, 3, and 1-->BF3 behave similarly to 1. Rotational energy barriers and the relative populations of the different energy states are calculated from 1H DNMR spectroscopy (DNMR, dynamic NMR). These results agree with those of semiempirical calculations. Without exception, the cis rotamer is energetically the more stable. The fixed conformation of 1 assists in elucidating the rotational preferences of the [3,3'-Co(1,2-C2B9H11)2]- ion in the absence of steric hindrance; the [3,3'-Co(1,2-C2B9H11)2]- ion is commonly accepted to present a cisoid orientation. Complex 1 is electronically similar to the [3,3'-Co(1,2-C2B9H11)2]- ion. Both have heteroatoms in the pi ligands, and they have the same electronegativity difference between the constituent atoms. This leads to a view of the [NC4H4]- as [7,8-C2B9H11]2- ion, with no steric implications. Therefore the [3,3'-Co(1,2-C2B9H11)2]- ion should be considered to have a cisoid structure, and the different rotamers observed to be the result of steric factors and of the interaction of the counterion with either B-H groups and/or ancillary ligands. The rotamer adopted is the one with the atoms holding the negative charges furthest apart. 相似文献