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1.
This article compares the role of policy instruments in stimulating long-term technological change in Danish and Norwegian wind industry. It concludes that although predictability has periodically been low, Denmark's broad portfolio of policies and measures has been well adapted to the different stages in the development of its wind industry. This has contributed to a high degree of innovation, successful establishment in niche markets, high degree of diffusion and establishment of domestic and international mass markets, and—in recent years—an increasingly successful replacement of senescent technology with new. The motivation of Norway's wind energy policies and measures—at least up until the late 1990s—has been to increase power supply rather than to stimulate industrial development and technological change. Policies and measures have been weaker than in Denmark; have been less stable over time; and stimulated the demand side much less. They have not sufficiently covered the wind industry's perceived needs on different stages in the development of new technology, and have not sufficiently stimulated continuous improvement, learning and new product development (dynamic efficiency) in industry. This has been part of the reason why there has been only a limited extent of innovation and diffusion of wind technology in Norway. 相似文献
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The kinetics of gasification of carbon deposited on nickel foils and nickel-alumina catalysts by steam, carbon dioxide and hydrogen are reported for the temperature range 450–850°C. At atmospheric pressure steam is the most effective gasifying agent. In all cases, the kinetic data obtained at lower temperatures (below 600°C) is consistent with control of the process by the chemical reaction. As the temperature increases, the rates of gasification by steam and carbon dioxide are limited by mass transfer effects. The concentration of methane near reaction sites affects the rate of hydrogen gasification above 650°C. 相似文献
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Since the mid-1970s new types of forest damage are observed in the Federal Republic of Germany. Typical damage symptoms in coniferous tree species are needle yellowing, reddening and premature loss of older foliage. Needle analysis carried out in damaged Norway spruce stands indicated that these phenomena, most of all needle yellowing, are influenced by the nutritional status of the trees. For the investigated sites Mg but also other elements, particularly P, S, K, Ca and Zn may play a causal role. As N is the most abundant element in the plant its form of uptake is important for a balanced nutrition. On the contrary to NO3-N high NH4-N uptake reduces the uptake of cations, particularly Mg and Ca, eventually inducing foliar discoloration symptoms on specific sites. Fertilizer experiments indicated that Mg fertilization is an appropriate tool to mitigate forest damages associated with Mg deficiency for a sustained time period. The application of N in the form of NH4-N may impede Mg uptake. This mechanism may cause severe damage in forest areas receiving continuously high NH4-N deposition. 相似文献
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A two-choice feeding bioassay was used to investigate the intra-specific repellency of the larval oral exudate of eastern and western spruce budworms,Choristoneura fumiferana (Clem.) andC. occidentalis Free., respectively. Results of the bioassay indicated that feeding behavior on artificial diet-drop feeding stations was modified in the presence of exudate, with feeding stations treated with conspecific exudate being avoided when an untreated station was available 3 cm away. Feeding was suppressed when a single, exudate-treated station was provided, or when the treated and untreated stations were separated by only 1 cm. The repellent effect functioned both inter- and intraspecifically. When induced to produce exudate,C. occidentalis larvae were not immediately repelled by either their own or other individuals' exudate. However, 24 hr after induction, test larvae were repelled by exudate from either source. In both species, larval oral exudate probably functions to repel conspecific competitors. 相似文献
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Utilising logging residues (termed brash in the UK) for energy production has become a focus for energy providers since the development of specialist baling machinery to improve the logistical and financial potential of this material. To explore a farm-scale operations scenario, brash from a mixed conifer, temperate zone forest was baled and chipped with commercial machinery to produce fuel-grade woodchip. Clear-fell logging procedures presented a range of brash configurations to facilitate baling machinery to produce compacted, tied, regular sized bales. Average hourly bale production and fresh weight tonnage output was 28 ± 2 bales/h and 12.4 t/h respectively. Extraction of bales and stacking along access road verges achieved an average 24 ± 2 bales/h. Woodchipping output averaged 11.8, 13.7 and 13.0 green t/h respectively for whole bale, log only and bale-log composite woodchip. Chipping production efficiency was affected by bale condition, handling and machinery performance but chiefly by site transport accessibility and logistical planning. The average total cost of in-farm delivered fuel quality woodchip product from brash bales was £25.22 (€29.67) per green tonne. Brash bale chips contained more than double the percentage of fines <6.3 mm compared to round log woodchips and also had significantly higher gross energy and nutrients content. Brash bale moisture content was observed to fluctuate widely and nutrients and energy content reduced during the 3-yr monitoring period. In conclusion, the combination of equipment and the confined production scenario was a viable process that provided fuel-grade woodchip at relatively low cost. 相似文献
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Effect of enzymatic high temperature prehydrolysis on the subsequent cellulose hydrolysis of steam‐pretreated spruce in high solids concentration
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Lisbet Harboe 《Architectural Design》2015,85(2):82-87
Founded by Andreas Grøntvedt Gjertsen and Yashar Hanstad, TYIN tegnestue Architects grew out of an initiative to provide sleeping accommodation for an orphanage in Thailand when the principals were only third-year architecture students. Norwegian architect Lisbet Harboe explains how the student-architects built up a practice while in schools by refocusing their studies and those of their peers on learning through their own experiences of construction. 相似文献
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Sebastian Eiter 《Landscape Research》2013,38(3):339-359
This article uses an activity-based understanding of landscape to explore values related to perceived land cover diversity. Perceptions within two user groups, members of landowner families and hiking tourists in a mountain area in western Norway, were related to a simultaneous land cover survey, and compared to experts' evaluations of land cover and to the aims of landscape protection in the area. Users perceived the area as being significantly more diverse and valuable than experts did, which stresses the importance of taking user perception into account in landscape protection and management. Some central landscape values were dependent upon land use outside the boundaries of the protected area. This illustrates that measures within structurally defined land units are not necessarily sufficient for maintenance of landscape values experienced by users. Land use in both respects, as an upholder of values and as a way of experiencing or perceiving them, should receive an increased role in the determination of management units. 相似文献