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1.
自然灾害引发的技术灾害(Na-Tech)对工业设施及生产设备带来了风险,加上化工园区聚集着大量危险化学品,这种耦合风险的扩大效应极易造成园区及周围区域的巨大经济损失和人员伤亡,因此化工园区Na-Tech事故逐渐受到广泛关注。本文通过对化工园区多灾种耦合风险影响因素进行辨识,分析耦合风险系统结构及作用机理,建立耦合风险系统结构模型与耦合风险演化模型,提出地震灾害引发的Na-Tech事故中设备泄漏概率模型;以某化工园区为例,应用耦合风险模型及设备泄漏概率模型,利用QRA软件对多灾种耦合下化工园区风险进行定量评价,对比传统工业灾害和地震灾害下个人风险和社会风险,得出地震灾害对化工园区风险影响,为化工园区多灾种耦合风险研究提供理论与方法支撑。 相似文献
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设施园艺可以让农业生产者通过一定的技术手段,提高农业生产效益,改变农作物的生长周期。文章在农业观光园的设计中可以利用这种技术方法来突出园区的农业特色,吸引非农业人口前来旅游观光和消费。 相似文献
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V. Papadopoulos J. Desmet J. Knockaert C. Develder 《International Journal of Hydrogen Energy》2018,43(34):16468-16478
So far, the biggest photovoltaic park in Belgium has been injecting all its energy into the electric distribution grid through a power purchase agreement with an electricity supplier. Due to decreasing and volatile wholesale electricity prices, the industrial partners/owners of the photovoltaic park are considering hydrogen storage in an attempt to increase the value proposition of their renewable energy installation. A major objective of the present work is to show how the utilization factor of the electrolyzer is affected by the design of the power supply system when the latter consists only of renewable energy sources instead of using the electric grid. Different hybrid designs were developed, by combining the existing photovoltaic source with wind power and state-of-the-art energy storage technologies (Vanadium Redox Flow or Lithium NMC). Finally, four scenarios were investigated, all considering a 1 MW PEM electrolyzer: A) 15 MW PV, B) 15 MW PV, 2MW Wind, C) 15 MW PV, 2 MW Wind, Battery, D) 15 MW PV, 15 MW Wind. The utilization factor was found as follows, for each scenario respectively: A) 41,5%, B) 65,5%, C) 66,0–86,0%, D) 82,0%. Furthermore, the analysis was extended to include economic evaluations (i.e. payback period, accumulated profit), specifically concerning scenario B and C. The results of this study lead to a number of conclusions such as: i) The utilization of the electrolyzer is limited when its power supply is intermittent. ii) Compared to PV, wind power makes larger contribution to the increase of the utilization factor, iii) 100% utilization can be achieved only if an energy storage system co-exists. iv) With a utilization factor at 65,5% scenario B can deliver a payback period in less than 8 years, if hydrogen is sold above 5€/kg. An analytic overview of all conclusions is presented in the last section of the paper. 相似文献
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Yingda Wang Qingyang You Ziyao Zhang Jiajun Chen Haijun Zhang 《Microscopy research and technique》2019,82(9):1455-1460
This article proposes to develop a WiFi‐controlled portable atomic force microscope (AFM). The AFM consists of a horizontal probe, controlling circuits, digital to analog (D/A) and analog to digital (A/D) interfaces, a microcomputer (Raspberry Pi, RPi), and a laptop. The proposed AFM uses a pocket‐size power supply to drive the controlling circuits, the D/A and A/D interfaces, as well as the RPi that constructs network hotspots and generates scanning signals. With special design and integration of the whole system, both of the AFM probe and electronic controlling system are portable. At a distance of 50 m from the proposed AFM, experiments in the constant height mode and the constant force mode are conducted to evaluate its performance. The results show that this WiFi‐controlled AFM has a maximum scan range of 3.6 × 3.6 μm2 with nanometer order resolution. Meanwhile, it achieves satisfactory image contrast, stability, and repeatability. Compared with conventional AFMs, the AFM proposed in this paper no longer relies on commercial AC mains supply or high‐voltage DC power supply, and realizes WiFi‐controlled AFM scanning and imaging in 50 m or farther without wire or network cable connection to a laptop or a desktop computer. Given credits to these features, WiFi‐controlled AFMs are expected to own a wider range of application, especially in isolated environments, outdoor researches, or even fieldwork investigations. 相似文献
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石化产业园区在走向循环经济发展的道路上,既迎来了新的发展机遇,但也面临着严峻的挑战,资源环境安全等约束日益趋紧。为了石化产业园区能够和谐稳步发展,分析了石化产业园区的危险性特点,强调了安全环保规划在园区发展中的作用和地位,总结了以往园区发展中存在的诸多问题,并提出了今后园区建设的安全环保规划重点任务,以期为做好石化产业园区的安全环保规划提供理论指导。 相似文献
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In low-temperature processes, there are interactions between heat exchanger network (HEN) and refrig-eration system. The modification on HEN of the chilling train for increasing energy recovery does not always coor-dinate with the minimum shaft work consumption of the corresponding refrigeration system. In this paper, a sys-tematic approach for optimizing low-temperature system is presented through mathematical method and exergy analysis. The possibility of"pockets", which appears as right nose section in the grand composite curve (EGCC) of the process, is first optimized. The EGCC with the pockets cutting down is designed as a separate part. A case study is used to illustrate the application of the approach for a HEN of a chilling train with propylene and ethylene refrig-erant system in an ethylene production process. 相似文献
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从服务对象、采用的标准规范、系统划分、计算指标、负荷分配、设计深度、水体防护等方面,对比了化工园区与城市区域控制性详细规划阶段给排水系统设计差异,分析了化工园区给排水设计的特点。 相似文献
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在总结国内外化工园区先进经验的基础上,提出了现代化工园区安全、环保体系的建设内容。化工园区安全、环保体系的全面建设,可以提升园区防范和应对各类环境、安全事故灾难的能力,降低园区发展所带来的各类安全、环境风险。 相似文献