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961.
962.
963.
Luis Cifuentes Cesar Dopazo Jesus Martin Pascale Domingo Luc Vervisch 《Flow, Turbulence and Combustion》2016,96(2):535-546
Local flow topologies have been identified and their interactions with the iso-scalar surfaces geometries have been investigated using the results of a three-dimensional direct numerical simulation (DNS) of a turbulent premixed methane-air flame in a piloted Bunsen burner configuration with tabulated chemistry. The universal teardrop shape of the joint probability density function (jpdf) of the second and third invariants of the velocity-gradient tensor disappears in the different flame regions under study. A ‘canonical’ vortex, which affects the fine-scale structure of the turbulent premixed flame, has been identified and analyzed at three times, differing by increments of the order of the Kolmogorov time micro-scale. 相似文献
964.
Shahida Anusha Siddiqui Ali Ali Redha Edgar Remmet Snoeck Shubhra Singh Jesus Simal-Gandara Salam A. Ibrahim Seid Mahdi Jafari 《Molecules (Basel, Switzerland)》2022,27(7)
Saffron is a valued herb, obtained from the stigmas of the C. sativus Linn (Iridaceae), with therapeutic effects. It has been described in pharmacopoeias to be variously acting, including as an anti-depressant, anti-carcinogen, and stimulant agent. The therapeutic effects of saffron are harbored in its bioactive molecules, notably crocins, the subject of this paper. Crocins have been demonstrated to act as a monoamine oxidase type A and B inhibitor. Furthermore, saffron petal extracts have experimentally been shown to impact contractile response in electrical field stimulation. Other research suggests that saffron also inhibits the reuptake of monoamines, exhibits N-methyl-d-aspartate antagonism, and improves brain-derived neurotrophic factor signaling. A host of experimental studies found saffron/crocin to be similarly effective as fluoxetine and imipramine in the treatment of depression disorders. Saffron and crocins propose a natural solution to combat depressive disorders. However, some hurdles, such as stability and delivery, need to be overcome. 相似文献
965.
Cesar Castillo-Quevedo Carlos Emiliano Buelna-Garcia Edgar Paredes-Sotelo Eduardo Robles-Chaparro Edgar Zamora-Gonzalez Martha Fabiola Martin-del-Campo-Solis Jesus Manuel Quiroz-Castillo Teresa del-Castillo-Castro Gerardo Martínez-Guajardo Aned de-Leon-Flores Manuel Cortez-Valadez Filiberto Ortiz-Chi Tulio Gaxiola Santos Jesus Castillo Alejandro Vsquez-Espinal Sudip Pan Jose Luis Cabellos 《Molecules (Basel, Switzerland)》2021,26(18)
In this study, we report the lowest energy structure of bare Cu13 nanoclusters as a pair of enantiomers at room temperature. Moreover, we compute the enantiomerization energy for the interconversion from minus to plus structures in the chiral putative global minimum for temperatures ranging from 20 to 1300 K. Additionally, employing nanothermodynamics, we compute the probabilities of occurrence for each particular isomer as a function of temperature. To achieve that, we explore the free energy surface of the Cu13 cluster, employing a genetic algorithm coupled with density functional theory. Moreover, we discuss the energetic ordering of isomers computed with various density functionals. Based on the computed thermal population, our results show that the chiral putative global minimum strongly dominates at room temperature. 相似文献
966.
967.
Ana M. V. Cavaleiro Julio D. Pedrosa de Jesus Robert D. Gillard Peter A. Williams 《Transition Metal Chemistry》1984,9(2):81-82
A number of studies of species formed in the tungsten(VI) oxide-R,R-(+)-tartaric acid-water system have been carried out(1–3). While various species have been proposed, it is generally accepted that three main ones predominate. Two have tungsten: (+)-tartaric acid [(+)-tartH4] ratios of 11 and the third has the same ratio of 12. This latter species cannot be that proposed by Avaloset al.
(3) since both ligands in their structure would have to be present as unidentates.Recently we have shown(4) that high resolution1H and13C n.m.r. studies were particularly useful in delineating the complexes formed in aqueous solution in the analogous molybdenum(VI) system. Thus, we turned our attention to the corresponding tungsten(VI) complexes, especially in view of the controversy surrounding the nature of the species formed in aqueous solution with (+)-tartH4. The results of our studies, presented below, indicate that only a few species are formed, and that these are quite analogous, as might be expected, to the previously described molybdenum(VI) species(4). In addition we have observed the formation of a mixed dimeric species [MoWO4{(+)-tart}2]4–, whose structure is akin to the mono-metallic complexes, as well as the well-characterized antimony(III) and arsenic(III) dimers of (+)-tartH4
(5). 相似文献
968.
Blas Pelegrín Juani L. Redondo Pascual Fernández Inmaculada García Pilar M. Ortigosa 《Journal of Global Optimization》2007,38(2):249-264
In many discrete location problems, a given number s of facility locations must be selected from a set of m potential locations, so as to optimize a predetermined fitness function. Most of such problems can be formulated as integer
linear optimization problems, but the standard optimizers only are able to find one global optimum. We propose a new genetic-like
algorithm, GASUB, which is able to find a predetermined number of global optima, if they exist, for a variety of discrete
location problems. In this paper, a performance evaluation of GASUB in terms of its effectiveness (for finding optimal solutions)
and efficiency (computational cost) is carried out. GASUB is also compared to MSH, a multi-start substitution method widely
used for location problems. Computational experiments with three types of discrete location problems show that GASUB obtains
better solutions than MSH. Furthermore, the proposed algorithm finds global optima in all tested problems, which is shown
by solving those problems by Xpress-MP, an integer linear programing optimizer (21). Results from testing GASUB with a set
of known test problems are also provided. 相似文献
969.
A. Lopez-Molinero J. R. Castillo Pilar Chamorro Pascual Asuncion Callizo 《Mikrochimica acta》1999,131(3-4):225-230
The generation of volatile species of As(III) as a means to introduce arsenic into a flame atomic absorption spectrometer
has been studied. The method is based on the reaction between As(III) and chloride ions in sulphuric acid medium. The reaction
is performed in a discontinuous or batch mode. With this method 130 μl of a solution containing 17.5% (w/v) sodium chloride
and As(III) are injected by a 500 ml.min−1 N2 carrier gas flow into 1 ml of concentrated sulphuric acid. The gaseous compounds generated are introduced into the spectrometer
through the nebulizer and As is determined.
Received October 3, 1998. Revision January 6, 1999. 相似文献
970.
Priyanka Maiti Priyanka Sharma Mahesha Nand Indra D. Bhatt Muthannan Andavar Ramakrishnan Shalini Mathpal Tushar Joshi Ragini Pant Shafi Mahmud Jesus Simal-Gandara Sultan Alshehri Mohammed M. Ghoneim Maha Alruwaily Ahmed Abdullah Al Awadh Mohammed Merae Alshahrani Subhash Chandra 《Molecules (Basel, Switzerland)》2022,27(5)
Among the various types of cancer, lung cancer is the second most-diagnosed cancer worldwide. The kinesin spindle protein, Eg5, is a vital protein behind bipolar mitotic spindle establishment and maintenance during mitosis. Eg5 has been reported to contribute to cancer cell migration and angiogenesis impairment and has no role in resting, non-dividing cells. Thus, it could be considered as a vital target against several cancers, such as renal cancer, lung cancer, urothelial carcinoma, prostate cancer, squamous cell carcinoma, etc. In recent years, fungal secondary metabolites from the Indian Himalayan Region (IHR) have been identified as an important lead source in the drug development pipeline. Therefore, the present study aims to identify potential mycotic secondary metabolites against the Eg5 protein by applying integrated machine learning, chemoinformatics based in silico-screening methods and molecular dynamic simulation targeting lung cancer. Initially, a library of 1830 mycotic secondary metabolites was screened by a predictive machine-learning model developed based on the random forest algorithm with high sensitivity (1) and an ROC area of 0.99. Further, 319 out of 1830 compounds screened with active potential by the model were evaluated for their drug-likeness properties by applying four filters simultaneously, viz., Lipinski’s rule, CMC-50 like rule, Veber rule, and Ghose filter. A total of 13 compounds passed from all the above filters were considered for molecular docking, functional group analysis, and cell line cytotoxicity prediction. Finally, four hit mycotic secondary metabolites found in fungi from the IHR were screened viz., (−)-Cochlactone-A, Phelligridin C, Sterenin E, and Cyathusal A. All compounds have efficient binding potential with Eg5, containing functional groups like aromatic rings, rings, carboxylic acid esters, and carbonyl and with cell line cytotoxicity against lung cancer cell lines, namely, MCF-7, NCI-H226, NCI-H522, A549, and NCI H187. Further, the molecular dynamics simulation study confirms the docked complex rigidity and stability by exploring root mean square deviations, root mean square fluctuations, and radius of gyration analysis from 100 ns simulation trajectories. The screened compounds could be used further to develop effective drugs against lung and other types of cancer. 相似文献