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1.
旨在确定全钒液流电池(VRB)储能系统(ESS)的最佳配置,以应对主动配电网(ADN)中风力发电的集成。相应地,提出了一种考虑储能的动态效率和寿命的电池储能系统优化配置方法。与以前的研究不同,所提出的储能优化配置方法中考虑了VRB的动态效率和寿命。此外,该方法综合考虑了风电消纳、减少负荷中断、减少温室气体排放、网损、VRB ESS的投资成本等综合收益,以经济指标用于评估VRB ESS的渗透率,设计的VRB ESS可以使得ADN的经济性达到最佳。最后,通过改进的IEEE 33节点系统对提出的电池储能系统优化配置方法进行了验证。测试结果证明了所提方法的正确性并分析了主动配电网的潮流运行特性。  相似文献   
2.
Leucokinins (LKs) constitute a family of neuropeptides identified in numerous insects and many other invertebrates. LKs act on G-protein-coupled receptors that display only distant relations to other known receptors. In adult Drosophila, 26 neurons/neurosecretory cells of three main types express LK. The four brain interneurons are of two types, and these are implicated in several important functions in the fly’s behavior and physiology, including feeding, sleep–metabolism interactions, state-dependent memory formation, as well as modulation of gustatory sensitivity and nociception. The 22 neurosecretory cells (abdominal LK neurons, ABLKs) of the abdominal neuromeres co-express LK and a diuretic hormone (DH44), and together, these regulate water and ion homeostasis and associated stress as well as food intake. In Drosophila larvae, LK neurons modulate locomotion, escape responses and aspects of ecdysis behavior. A set of lateral neurosecretory cells, ALKs (anterior LK neurons), in the brain express LK in larvae, but inconsistently so in adults. These ALKs co-express three other neuropeptides and regulate water and ion homeostasis, feeding, and drinking, but the specific role of LK is not yet known. This review summarizes Drosophila data on embryonic lineages of LK neurons, functional roles of individual LK neuron types, interactions with other peptidergic systems, and orchestrating functions of LK.  相似文献   
3.
Lithium-ion batteries are currently the alternative of choice to overcome the increasing demand of energy. However, besides the scarcity of lithium and limited geolocation, it is believed that such batteries have already reached their maximum maturity. Sodium batteries emerge as an alternative to produce the new, so called, post-lithium batteries. In this study, we explore (i) the effect of sodium content and sintering temperature in solid electrolytes based in NASICON-type compounds and (ii) the use of two methodologies to obtain porous NASICON samples: application of natural substances and organic materials as pore-formers and freeze casting. The main purpose is the attainment of hybrid quasi-solid state electrolytes, with enhanced room temperature conductivity, based on porous ceramic electrolyte layers infiltrated with ionic liquids. Using this approach, porous samples with different microstructure and porous morphology and distribution were achieved, providing an enhancement in conductivity (ranging from 0.45 to 0.96 mS cm−1 at 30 °C) of one order of magnitude for infiltrated samples respect to pore-free samples. According to these results the porous NASICON might be considered as a functional macroporous inorganic separator that can act as a Na+ reservoir.  相似文献   
4.
为了解决醇胺法燃烧后捕集二氧化碳再生能耗过高的问题,研究了一种向胺溶液中添加金属离子以降低其CO2解吸能耗的方法,称之为金属离子络合物热缓冲自热利用技术。以广泛商业化应用的单乙醇胺(MEA)溶液为研究载体,并在MEA溶液中分别添加金属离子铜或镍, 通过建立含有金属离子的MEA捕集CO2体系的化学反应模型,解释金属离子热缓冲剂效应的内在机理。机理显示在MEA-金属离子-CO2-H2O体系中,金属-MEA络合物作为一种有效的反应热缓冲剂,将有机胺吸收CO2过程中释放的反应热(放热反应)存储于金属络合物的解离键能中(吸热反应),在CO2高温解吸中通过其络合放热反应将储存的能量释放出来用于CO2解吸,形成自热再生低能耗CO2捕集技术,从而降低了MEA再生的能耗。本文进行了综合的实验测定来评价金属离子对MEA溶液捕集CO2过程的性能提升影响,包括CO2反应热、解吸速率、吸收-解吸循环负载、汽液平衡溶解度等。实验结果表明铜离子或镍离子作为添加剂,能增加MEA的CO2平衡循环负载14%~20%或7%~10%,同时能够降低MEA的CO2反应热值6.6%~24%或6.0%~20%。  相似文献   
5.
The damage induced in 3C-SiC epilayers on a silicon wafer by 2.3-MeV Si ion irradiation for fluences of 1014, 1015, and 1016 cm−2, was studied by conventional and high-resolution transmission electron microscopy (TEM/HRTEM). The evolution of extended defects and lattice disorder is followed in both the 3C-SiC film and Si substrate as a function of ion fluence, with reference to previous FTIR spectroscopy data. The likelihood of athermal unfaulting of native stacking faults by point defect migration to the native stacking faults is discussed in relation to damage recovery. Threshold energy densities and irradiation doses for dislocation loop formation and amorphous phase transformation are deduced from the damage depth profile by nuclear collisions. The role of electronic excitations on the damage recovery at high fluence is also addressed for both SiC and Si.  相似文献   
6.
ABSTRACT

The state-of-the-art article presents concepts of nanobelt nanofiller, inimitable properties of derived polymeric nanocomposite, applications, and outlook on challenges to gain next generation high-performance materials. Nanobelt is a one-dimensional nanostructured nanomaterial. Owing to minuscule size and high surface area, nanobelt possesses unique structural, optical, electronic, mechanical, and thermal characteristics. Nanobelt exists in various forms such as carbon nanobelt, polymer nanobelt, and inorganic. These nanobelts have been used to develop polymer/nanobelt nanocomposites. Homogeneous dispersion of nanobelt in polymer matrices is desirable to enhance the characteristics of polymer/nanobelt nanocomposite. Consequently, innovations in design, fabrication, and properties of various polymer/nanobelt nanocomposite are summarized. Applications of polymer/nanobelt nanocomposite are reviewed for Li-ion battery, supercapacitor, sensor, membrane, and biomedical arenas.  相似文献   
7.
张璐璐  谭伯川  李文坡 《化工学报》2021,72(10):5402-5411
采用简单的一步电沉积方法制备了Cu2+掺杂的MnO2材料。通过XRD、SEM、TEM等方法对材料进行了表征,结果表明其具有蓬松多孔的纳米结构,作为电池正极材料时有利于Zn2+的存储,具有较高的电池容量。与未掺杂样品相比Cu2+掺杂的MnO2材料有更好的电化学性能,在电流密度为200 mA/g时,比容量达到235 mAh/g,增加了47.8%,阻抗也由997.3 Ω降到了564.3 Ω。  相似文献   
8.
采用复合溶胶–凝胶法结合后续热处理,制备了具有包埋结构的氧化亚硅/碳(SiOx/C)复合负极材料。扫描电子显微镜分析结果表明:氧化亚硅纳米颗粒嵌入在无定形碳中。电化学性能测试表明:SiOx/C复合材料具有较高的比容量、优异的循环稳定性和倍率性能。材料在0.1 A/g的电流密度下100次循环后的可逆比容量为710 m A·h/g,容量几乎无衰减;在1.6 A/g的电流密度下,可逆比容量为380 m A·h/g。优异的电化学性能是由于材料的包埋结构能有效地缓冲SiOx充放电过程中的体积膨胀,保证材料的结构完整性和电化学循环稳定性。  相似文献   
9.
The low cost and highly efficient construction of electrocatalysts has attracted significant attention owing to the use of clean and sustainable energy technologies. In this work, cobalt nanoparticle decorated N-doped carbons (Co@NC) are synthesized by the pyrolysis of a cobalt covalent organic framework under an inert atmosphere. The Co@NC demonstrates improved electrocatalytic capabilities compared to N-doped carbon without the addition of Co nanoparticles, indicating the important role of cobalt. The well-dispersed active sites (Co–Nx) and the synergistic effect between the carbon matrix and Co nanoparticles greatly enhance the electrocatalytic activity for the oxygen reduction reaction. In addition, the Co content has a significant effect on the catalytic activity. The resulting Co@NC-0.86 exhibits a superb electrocatalytic activity for the oxygen reduction reaction in an alkaline electrolyte in terms of the onset potential (0.90 V), half-wave potential (0.80 V) and the limiting current density (4.84 mA·cm–2), and a high selectivity, as well as a strong methanol tolerance and superior durability, these results are comparable to those of the Pt/C catalyst. Furthermore, the superior bifunctional activity of Co@NC-0.86 was also confirmed in a home-built Zn-air battery, signifying the possibility for application in electrode materials and in current energy conversion and storage devices.  相似文献   
10.
目的 在保证膜层耐蚀性能的前提下,降低镁锂合金等离子电解氧化过程中的能量消耗.方法 分别使用常规NaOH-Na2SiO3电解体系与自研的NaOH-Na2SiO3-Na2B4O7-Na3C6H5O7·2H2O(柠檬酸钠)低能耗电解体系,对LA91型镁锂合金进行等离子电解氧化,并探究其放电过程.采用扫描电子显微镜(SEM)、能谱仪(EDS)、掠入射X射线衍射仪(GIXRD),表征等离子电解氧化膜层的表面形貌、元素组成、物相组成.通过电化学极化曲线、盐雾试验,测试膜层的耐蚀性.结果 使用低能耗体系对镁锂合金进行等离子电解氧化处理,可将膜层的单位体积能耗降低至12.87 kJ/(dm2·μm),节约能耗约50.34%.在两个体系中制备的膜层表面均产生等离子电解氧化的特征性孔洞.低能耗体系膜层孔洞数量较少,但孔洞直径差异较大,孔隙率为14.21%;常规体系膜层孔洞大小均匀,但数量较多,孔隙率为13.93%.两个膜层表面的主要元素均为O、Mg、Na和Si.在低能耗体系中制备的膜层,主要物相为方镁石型MgO,而在常规体系中制备的膜层,物相组成较为复杂.盐雾试验和电化学极化曲线结果显示,在两种体系中进行等离子电解氧化,均能提升镁锂合金的耐蚀性.低能耗等离子氧化处理后,镁锂合金的腐蚀电流密度降低约3个数量级,腐蚀速率降低约2个数量级,自腐蚀电位正移0.261 V,有效地提升了镁锂合金的耐蚀性,并且耐蚀性的提升程度要优于常规体系.结论 使用低能耗体系电解液进行等离子电解氧化,能够形成孔洞特征不同于常规体系的等离子电解氧化膜层.与常规体系下制备的膜层相比,其厚度、孔隙率并无较大差异,但能够在节约较多能耗的情况下制备出耐蚀性能更好的等离子电解氧化膜层.  相似文献   
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