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51.
Sydor JR Scalf M Sideris S Mao GD Pandey Y Tan M Mariano M Moran MF Nock S Wagner P 《Analytical chemistry》2003,75(22):6163-6170
A new chip-based method to identify protein-protein interactions was developed using the guanine nucleotide exchange factor GRF2 and two interacting proteins, Ras and calmodulin, as model proteins. A generic immobilization strategy for FLAG-tagged bait proteins on a protein-repellent streptavidin chip surface was implemented by presentation of an oriented anti-FLAG antibody. A flow cell device, integrating different chip surfaces, was developed, and the interaction of immobilized GRF2 with the two analytes was verified by fluorescence assays. On-chip tryptic digest assays were then performed on the capture surface and analyzed by microLC-MS/MS. The interaction of GRF2 with calmodulin and Ras was demonstrated, and the lower limit of detection was determined. We also implemented an on-chip immunoprecipitation assay to identify GRF2-binding partners from complex protein mixtures. Cells overexpressing FLAG-GRF2 were lysed and then incubated with the anti-FLAG chip. In addition to detecting GRF2, we also identified calmodulin, demonstrating that this technique can successfully identify endogenous levels of proteins, bound to recombinant bait proteins. This chip-based method has the advantage that no subsequent gel separations of protein complexes prior to LC-MS analysis are required and is therefore amenable to miniaturized high-throughput determination of protein-protein interactions. 相似文献
52.
Aicardi M. Davoli F. Giordano A. 《Selected Areas in Communications, IEEE Journal on》1989,7(2):219-225
A solution for the connection of personal computers or workstations to a central station (represented by a mainframe or a server attached to a local area network) by means of a shared radio channel is presented. Issues regarding the multiple-access protocol are discussed, and an access scheme that is based on the independent stations algorithm (ISA) is presented. The necessary modifications of the basic ISA are discussed, and the overall algorithm is analyzed and tested by simulation. An implementation that is currently being developed is briefly described, focusing on the choices made for the logical link control protocol, the transmission techniques, and the interface software 相似文献
53.
INTEREST: a reference-point-based interactive procedure for stochastic multiobjective programming problems 总被引:1,自引:1,他引:0
This paper presents a reference point-based interactive algorithm, which has been specifically designed to deal with stochastic
multiobjective programming problems. This algorithm combines the classical information used in this kind of methods, i.e.
values that the decision maker regards as desirable for each objective, with information about the probabilities the decision
maker wishes to accept. This novel aspect allows the method to fully take into account the randomness of the final outcome
throughout the whole solution process. These two pieces of information have been introduced in an adapted achievement-scalarizing
function, which assures each solution obtained to be probability efficient. 相似文献
54.
Summary Under the hypothesis that a statistical population can be represented by a density function in a similar way to that of the
optimum stratification problem dealt with in Dalenius (1957) and Dalenius and Hodges (1959) the estimation of the population
variance is analysed by means of the technique of equilibrated stratification. An unbiased estimator is suggested and it is
shown that, with optimum allocation, the precision of the estimator for sufficiently large sample size is always at least
that of the classical minimum variance unbiased estimator for a distribution-free setting. A numerical study complete the
article. 相似文献
55.
Ceramics display superior properties of hardness, chemical stability and refractoriness. However, their brittleness often limits their application as engineering components. The addition of second‐phase inclusions that influence crack propagation has been exhaustively studied. One of the main toughness enhancement theories proposes it is caused by the plastic deformation of ductile inclusions during crack propagation. This article proposes a model to explain the oxidation mechanisms of niobium particles embedded in an Al2O3 matrix, based on a thermogravimetric analysis. Two types of oxidation kinetics are identified here: linear and parabolic kinetics, with activation energies of 12.4 kJ/mol and 24.9 kJ/mol, respectively. Based on our results, a kinetic model is proposed to describe the oxidation of niobium particles embedded in alumina ceramic composite matrix. 相似文献
56.
In this paper we address the topic of energy and water optimization in the production of bioethanol from corn and switchgrass. We show that in order for these manufacturing processes to be attractive, there is a need to go beyond traditional heat integration and water recycling techniques. Thus, we propose a strategy based on mathematical programming techniques to model and optimize the structure of the processes, and perform heat integration including the use of multi-effect distillation columns and integrated water networks to show that the energy efficiency and water consumption in bioethanol plants can be significantly improved. Specifically, under some circumstances energy can even be produced and the water consumption can be reduced below the values required for the production of gasoline. 相似文献
57.
High‐fat diet induces endothelial dysfunction through a down‐regulation of the endothelial AMPK–PI3K–Akt–eNOS pathway 下载免费PDF全文
58.
59.
Cesar ElosuaAuthor Vitae Candido BariainAuthor VitaeAsuncion LuquinAuthor Vitae Mariano LagunaAuthor VitaeIgnacio R. MatiasAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(2):388-394
The construction of single mode optical fibre (SMF) sensors to handle with volatile organic compounds (VOCs), has been optimized to operate at the third telecommunication window (1550 nm). The main motivation is to take advantage of the photonic devices used in telecommunication systems that makes easier sensors multiplexing. Moreover, the low transmission attenuation at that wavelength offers the possibility of remote sensing. The sensing materials used suffer reversible structural alterations in the presence of VOC, such as colour change, which are detectable with a photonic system. Following the Electrostatic Self Assembly method (ESAm), a nanostructure is constructed onto cleaved ended SMF, which is doped with a sensing material. The fabrication of this type of sensors was focused on multimode fibres (MMF) and in the visible spectral range (VIS) so far. The implementation has been adapted to SMF and to operate around 1550 nm, specifically, by easing the adsorption of the VOCs molecules. It has been observed that the sensing material affects the morphology of the nanostructures as well and so, to the sensors response. The devices implemented show a potential use in the identification of single and complex mixtures of VOCs. 相似文献
60.
This paper describes a study on the contribution of linguistically-informed features to the task of quality estimation for machine translation at sentence level. A standard regression algorithm is used to build models using a combination of linguistic and non-linguistic features extracted from the input text and its machine translation. Experiments with three English–Spanish translation datasets show that linguistic features on their own are not able to outperform shallower features based on statistics from the input text, its translation and additional corpora. However, further analysis suggests that linguistic information can be useful to produce better results if carefully combined with other features. An in-depth analysis of the results highlights a number of issues related to the use of linguistic features. 相似文献