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991.
The present work focuses on a posteriori, equilibrium based, reconstruction of transverse stress profiles in the finite element analysis of FSDT laminated plates. The accuracy of this reconstruction depends on accuracy of the first and second-order derivatives of the plate stress resultants, which is not guaranteed by most available low-order plate finite elements. To cure this trouble, two different strategies, based on the Recovery by Compatibility in Patches procedure, are here proposed and compared. Numerical results of typical reconstructed transverse stress profiles are presented showing the effectiveness of the proposed approach. 相似文献
992.
Eunha Shim Gretchen B. Chapman Jeffrey P. Townsend Alison P. Galvani 《Journal of the Royal Society Interface》2012,9(74):2234-2243
Game theory is based on the assumption that individuals act according to self-interest and make decisions that maximize their personal payoffs. To test this fundamental assumption, we conducted a survey study in the context of influenza vaccination decisions. Contrary to the assumption of self-interest, we found that altruism plays an important role in vaccination decisions. Nevertheless, altruistic motivation has not yet been considered in epidemiological models, in predictions of vaccination decisions or in the design of vaccination policies. To determine the impact of altruism on the adherence to optimal vaccination policies and on resulting disease burden, we incorporated altruism into a game-theoretic epidemiological model of influenza vaccination. We found that altruism significantly shifted vaccination decisions away from individual self-interest and towards the community optimum, greatly reducing the total cost, morbidity and mortality for the community. Therefore, promoting altruism could be a potential strategy to improve public health outcomes. 相似文献
993.
M. Rodríguez-Pascual A. Gómez R. Mayo-García D. Pérez de Lara E. M. González A. J. Rubio-Montero J. L. Vicent 《Journal of Superconductivity and Novel Magnetism》2012,25(7):2127-2130
Nb films have been fabricated on top of array of Ni nanodots. The array of periodic pinning potentials modifies the vortex lattice for specific values of the external applied magnetic field. By means of an implemented code developed from scratch, computer simulations based only on the vortex?Cvortex and the vortex?Cnanodot interactions provide the total interaction between vortices and pinning sites as well as the position of the vortices in the array unit cell. This simulation approach could be performed on square, rectangular or triangular arrays of nanodefects of different size. 相似文献
994.
E. Negussie Y. de Haas F. Dehareng R.J. Dewhurst J. Dijkstra N. Gengler D.P. Morgavi H. Soyeurt S. van Gastelen T. Yan F. Biscarini 《Journal of dairy science》2017,100(4):2433-2453
Efforts to reduce the carbon footprint of milk production through selection and management of low-emitting cows require accurate and large-scale measurements of methane (CH4) emissions from individual cows. Several techniques have been developed to measure CH4 in a research setting but most are not suitable for large-scale recording on farm. Several groups have explored proxies (i.e., indicators or indirect traits) for CH4; ideally these should be accurate, inexpensive, and amenable to being recorded individually on a large scale. This review (1) systematically describes the biological basis of current potential CH4 proxies for dairy cattle; (2) assesses the accuracy and predictive power of single proxies and determines the added value of combining proxies; (3) provides a critical evaluation of the relative merit of the main proxies in terms of their simplicity, cost, accuracy, invasiveness, and throughput; and (4) discusses their suitability as selection traits. The proxies range from simple and low-cost measurements such as body weight and high-throughput milk mid-infrared spectroscopy (MIR) to more challenging measures such as rumen morphology, rumen metabolites, or microbiome profiling. Proxies based on rumen samples are generally poor to moderately accurate predictors of CH4, and are costly and difficult to measure routinely on-farm. Proxies related to body weight or milk yield and composition, on the other hand, are relatively simple, inexpensive, and high throughput, and are easier to implement in practice. In particular, milk MIR, along with covariates such as lactation stage, are a promising option for prediction of CH4 emission in dairy cows. No single proxy was found to accurately predict CH4, and combinations of 2 or more proxies are likely to be a better solution. Combining proxies can increase the accuracy of predictions by 15 to 35%, mainly because different proxies describe independent sources of variation in CH4 and one proxy can correct for shortcomings in the other(s). The most important applications of CH4 proxies are in dairy cattle management and breeding for lower environmental impact. When breeding for traits of lower environmental impact, single or multiple proxies can be used as indirect criteria for the breeding objective, but care should be taken to avoid unfavorable correlated responses. Finally, although combinations of proxies appear to provide the most accurate estimates of CH4, the greatest limitation today is the lack of robustness in their general applicability. Future efforts should therefore be directed toward developing combinations of proxies that are robust and applicable across diverse production systems and environments. 相似文献
995.
Yongxing Yang Cristina Ochoa-Hernández Patricia Pizarro Víctor A. de la Pe?a O’Shea Juan M. Coronado David P. Serrano 《Topics in Catalysis》2012,55(14-15):991-998
Arrays of nickel phosphide nanorods were successfully synthesized by nanocasting using mesostructured silica SBA-15 as a hard template (HT-Ni2P). After temperature-programmed reduction of the phosphate precursor infiltrated within the pore walls of SBA-15, the unsupported material was obtained by removing the silica matrix with diluted HF. The pore channel of the SBA-15 template stabilizes the Ni2P particles, preventing sintering after the high reduction temperature and shaping their elongated morphology. Moreover, HT-Ni2P catalyst shows an improvement in the textural properties with a significantly higher surface area than the reference sample synthesized in the absence of template. X-ray diffraction revealed that the only crystalline phase present in this material was Ni2P. On the other hand, transmission electron microscopy shows that the catalyst is mainly constituted by agglomerates of nanorods. Through EDX microanalysis the efficient removal of silicon was confirmed. Under hydrotreating conditions, nanorods of Ni2P show a fourfold enhancement in the conversion of methyl oleate with respect to conventional Ni2P synthesized in absence of hard template. Nevertheless, when these data are normalized to surface area, the specific activity of HT-Ni2P nanorods is significantly lower than that of the conventionally prepared sample. Differences in selectivity were also observed as Ni2P nanorods favored the decarboxylation reaction leading to a higher yield of n-heptadecane. 相似文献
996.
997.
Foundation heat exchangers (FHXs) are an alternative to more costly ground heat exchangers utilized in ground-source heat pump (GSHP) systems serving detached or semi-detached houses. Simulation models of FHX are needed for design and energy calculations. This paper looks at two approaches used for development of simulation models for FHX systems: a simplified analytical model and a detailed numerical model. The analytical model is based on superposition of line sources and sinks. The numerical model is a two-dimensional finite volume model implemented in the HVACSIM+ environment. Both the analytical and numerical models have been validated again experimental results from a test house located in Oak Ridge, Tennessee. Six geographically diverse locations are chosen for a parametric study; results of the two models are compared, and differences between the results are investigated. 相似文献
998.
J. C. Gasparetto F. S. F. Smolarek T. M. G. de Francisco L. C. Miranda R. Pontarolo P. F. Siqueira 《Journal of the American Oil Chemists' Society》2012,89(7):1211-1222
In this study, a new HPLC method was developed and validated for the determination of daidzin, genistin, glycitin, and their respective aglycones daidzein, genistein and glycitein in extracts from different stages of soy processing. The chromatographic separation was achieved using a Bonus RP 100 × 3.0 mm (3.5-μm particle size) column maintained at 35 °C. The mobile phase consisted of a gradient of water and acetonitrile both containing 0.1% formic acid. Analyses were conducted at a flow rate of 1.0 mL min−1 and the detector was set at 254 nm. Validation parameters indicated that the method has high selectivity and is linear over a range of 1.5–150 μg mL−1 for all compounds. The range of recovery was 95–102% with a RSD% <5% for intra-day and inter-day precision. The robustness study indicated that the flow rate was the only critical factor. The new HPLC–DAD method was successfully applied to real samples and excellent separation was achieved without the need of any sample pretreatment. 相似文献
999.
1000.