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991.
Malte Elson Johannes Breuer James D. Ivory Thorsten Quandt 《The Journal of communication》2014,64(3):521-542
Recent research has attempted to describe meaningful experiences with entertainment media that go beyond hedonic enjoyment. Most of this research focuses on noninteractive media, such as film and television. When applied to digital games, however, such research needs to account for not only the content of the medium, but also the unique dimensions of digital games that distinguish them from noninteractive media. Experiences with digital games are shaped by the game mechanics that define the users' interaction with game content, as well as by the opportunities for social interaction that many games offer. We argue that the complex interplay of these dimensions (narrative, mechanics, and context) facilitates or inhibits meaningful user experiences in ways that are unique to digital games. 相似文献
992.
Daniel Spinks Emma J. Shanks Laura A. T. Cleghorn Stuart McElroy Deuan Jones Daniel James Alan H. Fairlamb Julie A. Frearson Paul G. Wyatt Ian H. Gilbert 《ChemMedChem》2009,4(12):2060-2069
There is an urgent need for new drugs for the treatment of tropical parasitic diseases such as human African trypanosomiasis, which is caused by Trypanosoma brucei. The enzyme trypanothione reductase (TryR) is a potential drug target within these organisms. Herein we report the screening of a 62 000 compound library against T. brucei TryR. Further work was undertaken to optimise potency and selectivity of two novel‐compound series arising from the enzymatic and whole parasite screens and mammalian cell counterscreens. Both of these series, containing either a quinoline or pyrimidinopyrazine scaffold, yielded low micromolar inhibitors of the enzyme and growth of the parasite. The challenges of inhibiting TryR with druglike molecules is discussed. 相似文献
993.
Reports an error in "Where similarity beats redundancy: The importance of context, higher order similarity, and response assignment" by Ami Eidels, James T. Townsend and James R. Pomerantz (Journal of Experimental Psychology: Human Perception and Performance, 2008[Dec], Vol 34[6], 1441-1463). The DOIs for the article and the supplemental materials were incorrectly listed. The correct DOIs are provided in the erratum. (The following abstract of the original article appeared in record 2008-16831-008.) People are especially efficient in processing certain visual stimuli such as human faces or good configurations. It has been suggested that topology and geometry play important roles in configural perception. Visual search is one area in which configurality seems to matter. When either of 2 target features leads to a correct response and the sequence includes trials in which either or both targets are present, the result is a redundant-target paradigm. It is common for such experiments to find faster performance with the double target than with either alone, something that is difficult to explain with ordinary serial models. This redundant-targets study uses figures that can be dissimilar in their topology and geometry and manipulates the stimulus set and the stimulus-response assignments. The authors found that the combination of higher order similarity (e.g., topological) among the features in the stimulus set and response assignment can effectively overpower or facilitate the redundant-target effect, depending on the exact nature of the former characteristics. Several reasonable models of redundant-targets performance are falsified. Parallel models with the potential for channel interactions are supported by the data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Murphy James G.; MacKillop James; Skidmore Jessica R.; Pederson Ashley A. 《Canadian Metallurgical Quarterly》2009,17(6):396
Recent clinical research suggests that several self-report behavioral economic measures of relative reinforcing efficacy (RRE) may show utility as indices of substance abuse problem severity. The goal of the present study was to evaluate the reliability and validity of the Alcohol Purchase Task (APT), a RRE measure that uses hypothetical choices regarding alcohol purchases at varying prices (demand curves) to generate several indices of alcohol-related reinforcement. Participants were 38 college students who reported recent alcohol consumption. Both the raw alcohol purchase/consumption values and several of the computed reinforcement parameters (intensity & Omax) showed good to excellent 2-week test–retest reliability. Reinforcement parameters derived from both a linear-elasticity (Hursh, Raslear, Bauman, & Black, 1989) and an exponential (Hursh & Silberberg, 2008) demand curve equation were generally less reliable, despite the fact that both equations provided a good fit to participants’ reported consumption data. The APT measures of demand intensity (number of drinks consumed when price = 0), Omax (maximum expenditure), and elasticity (α) were correlated with weekly drinking, alcohol-related problems, and other self-report RRE measures (relative discretionary monetary expenditures toward alcohol and/or relative substance-related activity participation and enjoyment). Demand intensity was uniquely associated with problem drinking in a regression model that controlled for weekly consumption. These results provide support for the reliability and validity of the RRE indices generated with the APT. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Sensitivity of Simulating Hydrologic Processes to Gauge and Radar Rainfall Data in Subtropical Coastal Catchments 总被引:3,自引:1,他引:2
Jairo N. Diaz-Ramirez William H. McAnally James L. Martin 《Water Resources Management》2012,26(12):3515-3538
This research evaluated the impact of three rainfall datasets on hydrologic process simulations in two coastal catchments located in Alabama. In this study, rain gauge time series recorded by the U.S. National Oceanic and Atmospheric Administration (NOAA) and Geological Survey (USGS) along with radar precipitation data derived from NOAA National Weather Service (NWS) were input into the Hydrological Simulation Program??FORTRAN (HSPF). Automatic parameter calibration was performed using daily streamflow data recorded at USGS Fish and Magnolia River gauge stations from 07/01/2002 to 12/31/2008. HSPF parameters were optimized using the Model-Independent Parameter Estimation (PEST) program. Model parameter ranges were refined by incorporating physical characteristic of the study areas and after analyzing observed streamflow time series. This approach, in turn, helped PEST optimization tool to find the most physically-related set of parameters that can be transferred to any watershed with similar characteristics and minimum parameter calibration. On average, annual USGS and radar rainfall values were around 480?mm and 250?mm, respectively lower than NOAA precipitation records. Overall, it is found that the NOAA precipitation input data resulted in better daily flow simulations than results from radar and USGS rainfall time series. Streamflows derived from USGS rainfall time series showed the worst model performance at both catchment outlets because of missing data, low amounts, and temporal delay of peaks. This study found that annual actual evapotranspiration values were closed among rainfall time series and varied from 900 to 958?mm. Deep percolation values for Magnolia and Fish River, regardless of rainfall source, ranged from 66 to 192?mm/year. Major discrepancies were found at storm runoff values. Gauge rainfall time series yielded the closest streamflow values compared to observed flow time series at both watershed outlets. Rainfall derived from radar yielded consistent and acceptable runoff results in Fish and Magnolia River models. In both case studies, the high spatial variability of rainfall storm events was not adequately captured by any of the rainfall datasets and yielded high uncertainty in model results. 相似文献
996.
Wild boar is a species that is utilised for food and sport hunting throughout the world. Recent increases in natural populations and the potential of farming wild boars have stimulated interest in this species as a meat producer. Compared to domestic pigs, wild boars present a higher degree of carcass fatness and larger loin areas, more slow-twitch oxidative (I) and fast-twitch oxidative glycolytic (IIA) and less fast-twitch glycolytic (IIB) muscle fibres, and darker, less tender and leaner meat. Differences in diets might contribute to differences in cooked meat flavour and fatty acid composition between wild boars and domestic pigs. Higher α-tocopherol concentrations in wild boar might extend its meat shelf-life. Mechanical massaging of muscles, vacuum package ageing and addition of marinates have been attempted to tenderise wild boar meat. Further research on hunting protocols for wild boar, and value-added products from its meat, are needed. 相似文献
997.
Stewart Jennifer L.; Bismark Andrew W.; Towers David N.; Coan James A.; Allen John J. B. 《Canadian Metallurgical Quarterly》2010,119(3):502
Resting frontal electroencephalographic (EEG) asymmetry has been hypothesized as a marker of risk for major depressive disorder (MDD), but the extant literature is based predominately on female samples. Resting frontal asymmetry was assessed on 4 occasions within a 2-week period in 306 individuals aged 18–34 (31% male) with (n = 143) and without (n = 163) lifetime MDD as defined by the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (American Psychiatric Association, 1994). Lifetime MDD was linked to relatively less left frontal activity for both sexes using a current source density (CSD) reference, findings that were not accounted for solely by current MDD status or current depression severity, suggesting that CSD-referenced EEG asymmetry is a possible endophenotype for depression. In contrast, results for average and linked mastoid references were less consistent but demonstrated a link between less left frontal activity and current depression severity in women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Luchies Laura B.; Finkel Eli J.; McNulty James K.; Kumashiro Madoka 《Canadian Metallurgical Quarterly》2010,98(5):734
[Correction Notice: An erratum for this article was reported in Vol 99(1) of Journal of Personality and Social Psychology (see record 2010-12776-008). The graphs in Figure 2, on p. 741, and the graphs in Figure 3, on p. 742, were switched. The corrected figures in their entirety appear in the erratum.] We build on principles from interdependence theory and evolutionary psychology to propose that forgiving bolsters one's self-respect and self-concept clarity if the perpetrator has acted in a manner that signals that the victim will be safe and valued in a continued relationship with the perpetrator but that forgiving diminishes one's self-respect and self-concept clarity if the perpetrator has not. Study 1 employed a longitudinal design to demonstrate that the association of marital forgiveness with trajectories of self-respect over the first 5 years of marriage depends on the spouse's dispositional tendency to indicate that the partner will be safe and valued (i.e., agreeableness). Studies 2 and 3 employed experimental procedures to demonstrate that the effects of forgiveness on self-respect and self-concept clarity depend on the perpetrator's event-specific indication that the victim will be safe and valued (i.e., amends). Study 4 employed a longitudinal design to demonstrate that the association of forgiveness with subsequent self-respect and self-concept clarity similarly depends on the extent to which the perpetrator has made amends. These studies reveal that, under some circumstances, forgiveness negatively impacts the self. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Feature maps, in which one or more aspects of the environment are systematically represented over the surface of the cerebral cortex, are often found in primary sensory and motor cortical regions of the vertebrate brain. They have inspired a great deal of computational modelling, and this has provided evidence that such maps are emergent properties of the interactions of numerous cortical neurons and their adaptive, nonlinear connections. In this paper, we address the issue of how multiple feature maps that coexist in the same region of cerebral cortex align with each other. We hypothesize that such alignment is governed by temporal correlations: features in one map that are temporally correlated with those in another come to occupy the same spatial locations over time. To examine the feasibility of this hypothesis and to establish some of its detailed implications, we initially studied a computational model of primary sensorimotor cortex. Coexisting sensory and motor maps formed and generally aligned in a fashion consistent with the temporal correlation hypothesis. We summarize these results, and then mathematically analyse a simplified model of self-organization during unsupervised learning. We show that the properties observed computationally are quite general: that temporally correlated inputs become spatially correlated (i.e. aligned), while input patterns that are temporally anti-correlated tend to result in mutually exclusive (i.e. unaligned) spatial distributions. This work provides a framework in which to interpret and understand future experimental studies of map relationships. 相似文献
1000.