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991.
Elizabeth J. Mueller Alex Schwartz 《Journal of the American Planning Association. American Planning Association》2013,79(1):122-135
Problem: Most housing programs in the United States do not focus on the most pressing housing needs. In 2003 more than 13 million households spent at least half their incomes on rent or the costs of homeownership, an increase of more than 35% since 1993. The vast majority of these households were poor. Yet housing policy has shifted away from deep-subsidy programs targeted to the poorest households toward providing shallow subsidies to higher-income households. Purpose: This article considers whether, given that the federal government is unlikely to increase funding for low-income housing, state and local governments are likely to increase housing assistance to the lowest-income households in the future, how such assistance could be structured, and how states and localities might be persuaded or compelled to provide this assistance. Methods: We examine the income distribution of households supported by major programs administered by state and local governments and the extent to which these programs target the poor and provide them with sufficient levels of subsidy. We reviewed program data reported to funding agencies and trade associations, census data on housing problems compiled by the U.S. Department of Housing and Urban Development, and data from surveys of policies and practices conducted by academic researchers and policy organizations. Results and conclusions: We find that the shift to state and local administration of federal funds has not significantly shifted priorities. We provide evidence that states are not using their discretion go beyond federal requirements, and are not serving income groups below those they are required to serve. Locally funded programs are less likely to target the poor than state or federal programs. Takeaway for practice: Rather than hoping for substantial local housing assistance targeted to the poor, we recommend making more effective use of existing federal resources. Research support: None. 相似文献
992.
Alex Lord 《Planning Theory & Practice》2013,14(3):333-349
This review paper introduces a research agenda designed to invigorate interest in information economics as a conceptual framework within which to analyse the purported transition from regulatory land-use planning, such as that operating in England prior to 2004, to “spatial planning”. In considering one specific area of reform—the management of infrastructure provision—a research agenda is introduced to investigate a specific policy instrument, the Community Infrastructure Levy. It is approached as a transaction cost, the determination of which is a function of how information is traded between counterparties. In conceptualizing important information asymmetries between local planning authorities and the development industry a case is made for further empirical research. 相似文献
993.
A. Xu Z. N. Xie J. Y. Fu J. R. Wu Alex Tuan 《The Structural Design of Tall and Special Buildings》2014,23(9):641-663
With the nonstationary wind‐induced acceleration data from full‐scale measurements, an approach for estimation of the wind‐induced overturning bending moments for super‐tall buildings was proposed in this paper. The empirical mode decomposition was employed to decompose the measured acceleration data into a set of intrinsic mode functions and a residual component. To remove the baseline offset, the residual component and the intrinsic mode function components with long‐period were eliminated before their integrations into velocity and displacement components. Then, the intrinsic mode function components, which have the same dominant periods as the natural periods of the studied tall buildings, were extracted from the original signals, and the natural frequency and damping ratio for the first vibration mode of the building were identified. Finally, the wind‐induced overturning bending moments of the building were obtained from the generalized wind loads for the first vibration mode, which could be obtained from the time history analysis of dynamic equation. The Hilbert spectrum of wind‐induced overturning bending moments was utilized to observe its characteristics in both time and frequency domains, and the Strouhal number was thus identified. The proposed scheme and some selected results may be helpful for further understanding of wind effects on super‐tall buildings. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
994.
介绍了欧宝泰克公司生产的PW2/D2型针织物连续式平幅煮漂水洗生产线、冷轧堆染色机及DTR1/PW/TR型连续水洗机的性能和特点,与传统的溢流染色机进行了对比。对比结果表明,该湿处理连续生产线加工的产品光泽好、颜色均匀性佳、颜色深度饱和、无折痕,水、电、汽和染化料消耗低,可以降低成本25%~50%。 相似文献
995.
Glen A. Turley Ercihan Kiraci Alan Olifent Alex Attridge Manoj K. Tiwari Mark A. Williams 《The International Journal of Advanced Manufacturing Technology》2014,72(9-12):1665-1675
Multi-sensor coordinate measuring machines (CMM) have a potential performance advantage over existing CMM systems by offering the accuracy of a touch trigger probe with the speed of a laser scanner. Before these systems can be used, it is important that both random and systematic errors are evaluated within the context of its intended application. At present, the performance of a multi-sensor CMM, particularly of the laser scanner, has not been evaluated within an automotive environment. This study used a full-scale CNC machined physical representation of a sheet metal vehicle body to evaluate the measurement agreement and repeatability of critical surface points using a multi-sensor horizontal dual arm CMM. It was found that there were errors between CMM arms and with regard to part coordinate frame construction when using the different probing systems. However, the most significant effect upon measurement error was the spatial location of the surface feature. Therefore, for each feature on an automotive assembly, measurement agreement and repeatability has to be individually determined to access its acceptability for measurement with a laser scanner to improve CMM utilisation, or whether the accuracy of a touch trigger probe is required. 相似文献
996.
Inclusion of Palmaria palmata (red seaweed) in Atlantic salmon diets: effects on the quality,shelf‐life parameters and sensory properties of fresh and cooked salmon fillets 下载免费PDF全文
997.
Charpentier AD Kofoworola O Bergerson JA MacLean HL 《Environmental science & technology》2011,45(21):9393-9404
A life cycle-based model, GHOST (GreenHouse gas emissions of current Oil Sands Technologies), which quantifies emissions associated with production of diluted bitumen and synthetic crude oil (SCO) is developed. GHOST has the potential to analyze a large set of process configurations, is based on confidential oil sands project operating data, and reports ranges of resulting emissions, improvements over prior studies, which primarily included a limited set of indirect activities, utilized theoretical design data, and reported point estimates. GHOST is demonstrated through application to a major oil sands process, steam-assisted gravity drainage (SAGD). The variability in potential performance of SAGD technologies results in wide ranges of "well-to-refinery entrance gate" emissions (comprising direct and indirect emissions): 18-41 g CO(2)eq/MJ SCO, 9-18 g CO(2)eq/MJ dilbit, and 13-24 g CO(2)eq/MJ synbit. The primary contributor to SAGD's emissions is the combustion of natural gas to produce process steam, making a project's steam-to-oil ratio the most critical parameter in determining GHG performance. The demonstration (a) illustrates that a broad range of technology options, operating conditions, and resulting emissions exist among current oil sands operations, even when considering a single extraction technology, and (b) provides guidance about the feasibility of lowering SAGD project emissions. 相似文献
998.
R. Alex Speers Marvin A. Tung Timothy D. Durance Graham G. Stewart 《Journal of the Institute of Brewing》1992,98(4):293-300
Factors affecting flocculation of brewing yeast, our current understanding of the process and traditional methods of assessing flocculence are discussed in this review. In spite of extensive study during the last two decades, a number of uncertainties and controversies regarding yeast flocculation still remain. This confusion is due in part to the polyploid or aneuploid nature of most brewing strains studied. At present, uncertainty exists as to the number of genes involved in flocculation as well as the nature and mode of action of the resulting gene products. Another restriction to our investigation of flocculation is the lack of a fundamental and standard test method. Along with a general discussion of yeast flocculation, this report will note conflicting reports concerning the influence of temperature, the effect of metal ions such as magnesium and barium, and the importance of the carboxyl and phosphate groups in yeast cell—cell interactions. As well, past and current methods employed for the assay of brewing yeast flocculation will be discussed. 相似文献
999.
R. Alex Speers Marvin A. Tung Timothy D. Durance Graham G. Stewart 《Journal of the Institute of Brewing》1992,98(6):525-531
In this review, areas of colloid science including the DLVO theory, flocculation kinetics and suspension rheology are outlined and their applicability to the study of yeast flocculation discussed. Specifically, fundamental methods of predicting cell-cell interaction energies, orthokinetic flocculation rates and rheological flow properties of flocculent suspensions are detailed. While the application of these theories to brewing systems is somewhat difficult, they may aid our understanding of brewing yeast flocculation. The limited information available on the colloidal nature and properties of brewing yeast cells is also summarized. 相似文献
1000.
This work reports on the non‐linear regression modelling of brewing fermentations. Evaluation of the decline in Plato with time from commercial datasets found a sigmoidal‐shaped logistic function best described the data. Four fermentation parameters, the initial and final gravities as well as the slope and midpoint at the inflection point of the curve were derived from a simplex search technique to minimize the residual sum of squares. The number of times the yeast was repitched had no effect (p > 0.05) on the fermentation. The starting temperature increased the fermentation rate (p < 0.01) while decreasing (p < 0.001) the time to the fermentation midpoint. Final gravities were also positively influenced by initial fermentation temperature (p < 0.001). This paper also illustrates the construction of prediction intervals about the predicted function and for the first time, allows the prediction of process deviations in the fermentation. Prediction intervals such as these can be used in a similar fashion to control charts. The statistical techniques reported in this paper can be used to make informed decisions (Evidence Based Practice) regarding fermentation procedures. For example, one could determine the number of yeast croppings possible before a significant change is observed in any of the fermentation parameters. These techniques can be used to examine the effect of process changes (e.g., temperature, yeast strain or starting gravity) on the fermentation process by statistically examining for changes in the four fermentation parameters (i.e., the initial and final gravities as well as the slope and midpoint at the inflection point of the fermentation curve). These techniques can also be used to evaluate various fermentation treatments or when developing a new strain or higher gravity wort. 相似文献