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21.
介绍了如何在兼容ARM V4指令集的32位RISC处理器(FA526)所构建的SoC平台上(即FIE8100),运用智原科技所提价的FA526-Linux开发包通过armboot装载Linux操作系统。使开发人员可以在基于FIE8100 SoC的仿真平台-MediaCreative!在进行二次开发和验证的设计方法。 相似文献
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23.
FTU的重合闸控制策略 总被引:1,自引:0,他引:1
针对多分段、多连接和多供电途径的网格架空配电网的自动化系统,提出了一套馈线终端单元(FTU)重合闸控制策略。该策略与变电站10kV出线断路器的重合闸控制相互配合,能较好地实现当发生暂时性故障后的迅速恢复供电。文中还给出了实例分析。 相似文献
24.
FA and tocopherol composition of Vietnamese oilseeds 总被引:1,自引:0,他引:1
Bertrand?MatthausEmail author Klaus?Vosmann Long?Quoc?Pham Kurt?Aitzetmüller 《Journal of the American Oil Chemists' Society》2003,80(10):1013-1020
Seeds of 40 oilseed species from 23 different plant families (Brassicaceae, Cucurbitaceae, Fabaceae, Sapindaceae, Malvaceae,
Gnetaceae, Clusiaceae, Bruseraceae, Ranunculaceae, Convolvulaceae, Amaranthaceae, Tiliaceae, Basellaceae, Solanaceae, Umbelliferae,
Labiatae, Compositae, Theaceae, Euphorbiaceae, Caesalpiniaceae, Sapotaceae, Anacardiaceae, and Connaraceae) grown in Vietnam
were analyzed for oilseed oil content, FA, and vitamin E. The seed oil content varied between 0.2 g/100 g for Mangifera indica and 75.7 g/100 g for Calophyllum inophyllum, whereas only nine seeds contained more than 40% oil. The tocopherol content ranged from 26 (Sapindus mukorossi) to 9361 mg/kg (Litchi chinensis). In nine seed oils unusual FA such as conjugated, cyclopropenoic, or epoxy FA were found. 相似文献
25.
Hiromi?YoshidaEmail author Kyoko?Matsuda Yuki?Hirakawa Yoshiyuki?Mizushina 《Journal of the American Oil Chemists' Society》2003,80(7):665-674
To clarify the effects of microwave roasting on the distribution of tocopherols and FA of phospholipids within soybeans, whole
soybeans (Glycine max) were treated by microwave and further evaluted as compared to a raw sample. Tocopherol homologs, measured using HPLC, and
phospholipid profiles, quantified with GC, were determined in the seed coat, the embryonic axis, and selections of cotyledons
separated from three cultivars. The tocopherols were predominantly detected in the axis, followed by the cotyledons, and then
very little in the coat. As much as 25% of the individual tocopherols originally present in the coat were lost at 12 min of
roasting, whereas <25% was lost in the cotyledons and the axis after 20 min of roasting. The greatest rate of phospholipid
loss (P<0.05) was observed in PE, followed by PC and PI, and their changing patterns were more pronounced in the coat than in the
cotyledons or the axis. Thus, tocopherol content and phospholipid profiles change with microwave roasting according to tissue. 相似文献
26.
Scientific analysis of energy consumption and its influencing factors is of great importance for energy strategy and policy planning. The energy consumption in China 1953–2006 is estimated by applying the energy ecological footprint (EEF) method, and the fluctuation periods of annual China's per capita EEF (EEFcpc) growth rate are analyzed with the empirical mode decomposition (EMD) method in this paper. EEF intensity is analyzed to depict energy efficiency in China. The main timescales of the 37 factors that affect the annual growth rate of EEFcpc are also discussed based on EMD and factor analysis methods. Results show three obvious undulation cycles of the annual growth rate of EEFcpc, i.e., 4.6, 14.4 and 34.2 years over the last 53 years. The analysis findings from the common synthesized factors of IMF1, IMF2 and IMF3 timescales of the 37 factors suggest that China's energy policy-makers should attach more importance to stabilizing economic growth, optimizing industrial structure, regulating domestic petroleum exploitation and improving transportation efficiency. 相似文献
27.
28.
Exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish 总被引:1,自引:0,他引:1
Robert J. Letcher Jan Ove Bustnes Christian Sonne Mathilakath M. Vijayan 《The Science of the total environment》2010,408(15):2995-10202
Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely based on correlations between biomarker endpoints (e.g., biochemical processes related to the immune and endocrine system, pathological changes in tissues and reproduction and development) and tissue residue levels of OHCs (e.g., PCBs, DDTs, CHLs, PBDEs and in a few cases perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonates (PFSAs)). Some exceptions include semi-field studies on comparative contaminant effects of control and exposed cohorts of captive Greenland sled dogs, and performance studies mimicking environmentally relevant PCB concentrations in Arctic charr. Recent tissue concentrations in several arctic marine mammal species and populations exceed a general threshold level of concern of 1 part-per-million (ppm), but a clear evidence of a POP/OHC-related stress in these populations remains to be confirmed. There remains minimal evidence that OHCs are having widespread effects on the health of Arctic organisms, with the possible exception of East Greenland and Svalbard polar bears and Svalbard glaucous gulls. However, the true (if any real) effects of POPs in Arctic wildlife have to be put into the context of other environmental, ecological and physiological stressors (both anthropogenic and natural) that render an overall complex picture. For instance, seasonal changes in food intake and corresponding cycles of fattening and emaciation seen in Arctic animals can modify contaminant tissue distribution and toxicokinetics (contaminant deposition, metabolism and depuration). Also, other factors, including impact of climate change (seasonal ice and temperature changes, and connection to food web changes, nutrition, etc. in exposed biota), disease, species invasion and the connection to disease resistance will impact toxicant exposure. Overall, further research and better understanding of POP/OHC impact on animal performance in Arctic biota are recommended. Regardless, it could be argued that Arctic wildlife and fish at the highest potential risk of POP/OHC exposure and mediated effects are East Greenland, Svalbard and (West and South) Hudson Bay polar bears, Alaskan and Northern Norway killer whales, several species of gulls and other seabirds from the Svalbard area, Northern Norway, East Greenland, the Kara Sea and/or the Canadian central high Arctic, East Greenland ringed seal and a few populations of Arctic charr and Greenland shark. 相似文献
29.
为了更有效的控制干法聚合工艺下聚合物的游离酸度,对聚合物游离酸度在实际生产工艺中的变化进行研究,了解淤浆中SO2的吸收,亚硫酸氢盐氧化成硫酸氢盐,是游离酸度变化的主要原因。控制几个关键部位的pH和提高头道运行洗涤效果,最终达到有效控制游离酸度的目的。 相似文献
30.
探讨FA322B型并条机的常见故障分析及故障排除方法。介绍了FA322B型并条机的性能特点。分析了并条机17种常见故障的表现形式、产生原因以及具体的排除方法。就该并条机日常维护和保养提出了详细的建议。认为:所列举的常见故障产生原因分析和排除方法是实践经验的总结,对维护使用好该型并条机,充分发挥其优良的性能有较好的指导作用。 相似文献