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(Y1-x%Cex%)3Al5O12 (x = 0.2,0.4,0.6,0.8,1.0) transparent ceramics were fabricated by vacuum sintering technology, followed by air annealing at different temperatures. Transmittance of ceramics, valence of cerium, and luminescent properties with varying annealing temperatures are studied in detail. The negative effect of Ce3+ oxidation induced by annealing gets increasingly evident when Ce concentration increases. Collaborating Ce:YAG ceramics with InGaN blue chips, light-emitting diodes (LEDs) with superior performance were constructed. The relationships between Ce concentration, annealing temperature, and luminous flux of LEDs are elucidated, showing that the optimized annealing temperature of Ce:YAG ceramics decreases from 1200 °C to 900 °C as Ce concentration increases from 0.2 at% to 1.0 at%. The luminous fluxes of optimized LEDs increase by ~10 % compared with that of unannealed LEDs.  相似文献   
3.
BackgroundThe last decade has noticed the expansion of green materials, which aims to reduce the human impact on the environment. Green polymers are clearly tendency subdivision of this stream and numerous bio-sourced plastics have been developed. Recent research has further focused on the development of new bio-based materials such as edible/biodegradable films for food products.Scope and approachFish gelatin (FG), a protein with recreatable reserve, biodegradability, and processability, has a remarkable potential in bio-packaging. However, there have been noticeable issues concerning the use of FG as packing material, including its low mechanical strength, poor moisture stability, and poor water barrier properties. This paper aims to review the state-of-the-art in development of FG-based films and highlights how they play a crucial role in modifying the properties of such films. Various types of nanofillers that have been included into FG to fabricate bio-nanocomposite films, such as nanoclays (montmorillonite, sepiolite), polysaccharide nanofillers (nanowhiskers/nanofibers), metal ions (silver, copper) and metal oxides nanoparticles (ZnO, TiO2) are reviewed.Key findings and conclusionsCross-linking is a promising technique to improve the performance and applicability of FG-based biomaterials, particularly respecting their water sensitivity, which hinders many of their potential uses as food contact materials. Bio-nanocomposite technology may help to make high-performance materials with extra bio-functional properties, and it is anticipated to be a dynamic research in the future. In general, more research is required to ameliorate application processes of FG films, especially physical aspects, to be suitable for bio-packaging application.  相似文献   
4.
面向中小型服装企业的个性化定制订单管理体系构建   总被引:1,自引:0,他引:1  
在开展个性化定制业务过程中,中小型服装企业易存在市场应变能力不强、信息化投入不足、数据利用能力较弱等问题,为此,构建了一个基于软件即服务(SaaS)模式的订单云管理体系。在分析该管理体系主要功能需求的基础上,优化提出了可充分借助云计算服务的服装个性化定制业务流程,设计了易于计算机处理的物料管理编码和业务数据信息体系。基于三级分层搭建了该订单管理体系的技术架构,设计了主要业务单元的智能化操作平台和核心计算技术。最后采用Java语言进行订单管理体系的开发,实现了订单信息的全流程、实时化、全方位共享,以期有效提升服装个性化定制业务的信息化管理水平。  相似文献   
5.
海藻是海洋中未开发完全的生物新资源,富含各种有利用价值的活性代谢产物。为了确定海藻中次级代谢产物的丰富度,该实验利用化学筛选方法(薄层层析色谱(TLC)、高效液相色谱(HPLC)、气相色谱-质谱(GC-MS))对江篱、刺麒麟菜、异枝麒麟菜、石花菜及小球藻这五株海藻中的次级代谢产物进行初步筛选。结果表明,通过薄层层析色谱和高效液相色谱分析得出江蓠和石花菜显色明显,代谢产物丰富且易于提取分离。通过气相色谱-质谱分析色谱分析得出,石花菜、小球藻的石油醚相成分复杂,未知化合物较多,特别是石花菜和小球藻可以进行重点研究,为后续海藻活性代谢产物研究与应用上的研发提供有力的实验基础。  相似文献   
6.
Hydrogen evolution through photoelectrochemical (PEC) water splitting by tungsten oxide-based photoanodes, as a stable and environmental-friendly material with moderate band gap, has attracted significant interest in recent years. The performance of WO3 photoanode could be hindered by its poor oxygen evolution reaction kinetics and high charge carrier recombination rate. Additionally, scalable and cost-effective commercial procedure to prepare nanostructured electrodes is still challenging. We present, for the first time, a novel and scalable method to fabricate highly efficient self-supported WO3/W nanostructured photoanodes from commercial W–Cu powder metallurgy (P/M) parts for water splitting. The electrodes were prepared by electrochemical etching of Cu networks followed by hydrothermal growth of WO3 nanoflakes. Interconnected channels of W skeleton provided high active surface area for the growth of WO3 nanoflakes with a thickness of ~40 nm and lateral dimension of ~250 nm. The optimized photoelectrode having 35% interconnected porosity exhibited an impressive current density of 4.36 mA cm−2 comprising a remarkable photocurrent of 1.71 mA cm−2 at 1.23 V vs. RHE under 100 mW cm−2 simulated sunlight. This achievement is amongst the highest reported photocurrents for WO3 photoelectrodes with tungsten substrate reported so far. Impedance and Mott-Schottky analyses evidenced fast charge transfer, low recombination rate, and accelerated O2 detachment provided by optimum 3D porous WO3/W electrode. Due to the nature of the commercial P/M parts and low-temperature hydrothermal processing, the procedure is cost-effective and scalable which can pave a new route for the fabrication of highly porous and efficient water splitting electrodes.  相似文献   
7.
A novel collector 1-(2-hydroxyphenyl)hex-2-en-1-one oxime (HPHO) was synthesized from 2-hydroxy acetophenone and butyraldehyde. Its flotation performance and adsorption mechanism to malachite were investigated by flotation test, zeta potential, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis techniques. Compared with benzohydroxamic acid (BA), 1-(2-hydroxyphenyl)ethan-1-one oxime (HPEO) and sodium isobutyl xanthate (SIBX), HPHO exhibited excellent collecting power to malachite without additional reagents, such as Na2S regulator and methyl isobutyl carbinol (MIBC) frother. Results of zeta potential indicated that HPHO was coated on malachite surfaces through a chemisorption process. FTIR and XPS data gave clear evidence for the formation of Cu–oxime complex on malachite surfaces after HPHO adsorption through the linkage between C=C, –OH, N–OH group and Cu species.  相似文献   
8.
针对大部分服装企业存在生产流水线编制效率较低以及生产周期长的普遍现象,提出一种服装工序编排方案自动生成和单件流生产线仿真运行的方法。首先分析服装生产工序编排方法和影响因素,采用拓扑方法和遗传算法相结合,在MatLab(R2016b)软件中建立自动优化模型,实现工序的自动编排;然后考虑服装生产数量和生产线设备情况,采用仿真技术,在Plant Simulation仿真软件中,根据实际生产对工序编排方案进行流水线仿真运行,得出直观可视的仿真结果,实现流水线平衡再优化。生产实例验证表明,流水线编制效率为90.8%,比原有效率提高12.8%,节省流水线编排方案在投产前的平衡调试时间,生产周期缩短。  相似文献   
9.
为提高工业机器人的柔性化及智能化水平,同时满足数据的实时共享、监控,使控制系统具有可扩展性与可移植性,设计了一种基于x86平台和RSI的工业机器人开放式控制系统。引入RSI后可载入应用程序包,实现PC工控机与KUKA机器人系统的实时性数据交换。运用模块化设计思路,针对硬件系统,制定软件系统平台的各功能模块,配合Windows操作系统的数据处理能力,在保证工业机器人实时性的前提下,实现了功能的扩展性和增减性。该系统在KUKA工业机器人力反馈实验平台上进行了可行性验证,试验表明,此开放式控制系统的实时响应性良好,满足预期控制要求。  相似文献   
10.
The substantial subsidizing of energy prices over the years has led to high energy consumption, inefficiencies, fiscal pressures, and environmental problems in Iran. To address the increasing socio-economic problems associated with the energy subsidies, the government embarked on an aggressive energy price reform through which energy subsidies were removed and cash handouts were given to all households in 2010. In this paper, I analyze the effectiveness of the energy price reform in Iran by estimating energy demand elasticities for households in different income groups. I apply a two-stage consumer optimization model and estimate the system of energy expenditures shares using the household budget survey data for the period 2001–2008. The results show that the overall price elasticities of demand are small, but income elasticities are close to one. The results also indicate heterogeneous responses to energy price and income changes in different income groups. Specifically, the urban households show stronger response to price changes, but rural households, particularly mid-income households, to income changes. These findings suggest that the current policy of price increases would not solely be able to reduce energy consumption and, therefore, it should be geared towards increasing energy efficiency through a series of price and non-price measures.  相似文献   
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