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991.
Peng Wang Caixia Li Shihua Dong Xiaoli Ge Peng Zhang Xianguang Miao Zhiwei Zhang Chengxiang Wang Longwei Yin 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(30)
The large‐scale commercial application of lithium–oxygen batteries (LOBs) is overwhelmed by the sluggish kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) associated with insoluble and insulated Li2O2. Herein, an elaborate design on a highly catalytic LOBs cathode constructed by N‐doped carbon nanotubes (CNT) with in situ encapsulated Co2P and Ru nanoparticles is reported. The homogeneously dispersed Co2P and Ru catalysts can effectively modulate the formation and decomposition behavior of Li2O2 during discharge/charge processes, ameliorating the electronically insulating property of Li2O2 and constructing a homogenous low‐impedance Li2O2/catalyst interface. Compared with Co/CNT and Ru/CNT electrodes, the Co2P/Ru/CNT electrode delivers much higher oxygen reduction triggering onset potential and higher ORR and OER peak current and integral areas, showing greatly improved ORR/OER kinetics due to the synergistic effects of Co2P and Ru. Li–O2 cells based on the Ru/Co2P/CNT electrode demonstrate improved ORR/OER overpotential of 0.75 V, excellent rate capability of 12 800 mAh g?1 at 1 A g?1, and superior cycle stability for more than 185 cycles under a restricted capacity of 1000 mAh g?1 at 100 mA g?1. This work paves an exciting avenue for the design and construction of bifunctional catalytic cathodes by coupling metal phosphides with other active components in LOBs. 相似文献
992.
Qiao Huang Travis P. Pollard Xiaolei Ren Doyoub Kim Alexandre Magasinski Oleg Borodin Gleb Yushin 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(6)
The rapid development of ultrahigh‐capacity alloying or conversion‐type anodes in rechargeable lithium (Li)‐ion batteries calls for matching cathodes for next‐generation energy storage devices. The high volumetric and gravimetric capacities, low cost, and abundance of iron (Fe) make conversion‐type iron fluoride (FeF2 and FeF3)‐based cathodes extremely promising candidates for high specific energy cells. Here, the substantial boost in the capacity of FeF2 achieved with the addition of NiF2 is reported. A systematic study of a series of FeF2–NiF2 solid solution cathodes with precisely controlled morphology and composition reveals that the presence of Ni may undesirably accelerate capacity fading. Using a powerful combination of state‐of‐the‐art analytical techniques in combination with the density functional theory calculations, fundamental mechanisms responsible for such a behavior are uncovered. The unique insights reported in this study highlight the importance of careful selection of metals and electrolytes for optimizing electrochemical properties of metal fluoride cathodes. 相似文献
993.
Xiangjun Pu Huiming Wang Dong Zhao Hanxi Yang Xinping Ai Shunan Cao Zhongxue Chen Yuliang Cao 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(32)
The increasing demands for renewable energy to substitute traditional fossil fuels and related large‐scale energy storage systems (EES) drive developments in battery technology and applications today. The lithium‐ion battery (LIB), the trendsetter of rechargeable batteries, has dominated the market for portable electronics and electric vehicles and is seeking a participant opportunity in the grid‐scale battery market. However, there has been a growing concern regarding the cost and resource availability of lithium. The sodium‐ion battery (SIB) is regarded as an ideal battery choice for grid‐scale EES owing to its similar electrochemistry to the LIB and the crust abundance of Na resources. Because of the participation in frequency regulation, high pulse‐power capability is essential for the implanted SIBs in EES. Herein, a comprehensive overview of the recent advances in the exploration of high‐power cathode and anode materials for SIB is presented, and deep understanding of the inherent host structure, sodium storage mechanism, Na+ diffusion kinetics, together with promising strategies to promote the rate performance is provided. This work may shed light on the classification and screening of alternative high rate electrode materials and provide guidance for the design and application of high power SIBs in the future. 相似文献
994.
Yang Liu Xiangcun Li Weiming Shen Yan Dai Wei Kou Wenji Zheng Xiaobin Jiang Gaohong He 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(32)
With the rapid growth of material innovations, multishelled hollow nanostructures are of tremendous interest due to their unique structural features and attractive physicochemical properties. Continued effort has been made in the geometric manipulation, composition complexity, and construction diversity of this material, expanding its applications. Energy storage technology has benefited from the large surface area, short transport path, and excellent buffering ability of the nanostructures. In this work, the general synthesis of multishelled hollow structures, especially with architecture versatility, is summarized. A wealth of attractive properties is also discussed for a wide area of potential applications based on energy storage systems, including Li‐ion/Na‐ion batteries, supercapacitors, and Li–S batteries. Finally, the emerging challenges and outlook for multishelled hollow structures are mentioned. 相似文献
995.
Gi Dae Park Jeong Hoo Hong Jae Hun Choi Jong‐Heun Lee Yang Soo Kim Yun Chan Kang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(24)
Multicomponent materials with various double cations have been studied as anode materials of lithium‐ion batteries (LIBs). Heterostructures formed by coupling different‐bandgap nanocrystals enhance the surface reaction kinetics and facilitate charge transport because of the internal electric field at the heterointerface. Accordingly, metal selenites can be considered efficient anode materials of LIBs because they transform into metal selenide and oxide nanocrystals in the first cycle. However, few studies have reported synthesis of uniquely structured metal selenite microspheres. Herein, synthesis of high‐porosity CoSeO3 microspheres is reported. Through one‐pot oxidation at 400 °C, CoSex–C microspheres formed by spray pyrolysis transform into CoSeO3 microspheres showing unordinary cycling and rate performances. The conversion mechanism of CoSeO3 microspheres for lithium‐ion storage is systematically studied by cyclic voltammetry, in situ X‐ray diffraction and electrochemical impedance spectroscopy, and transmission electron microscopy. The reversible reaction mechanism of the CoSeO3 phase from the second cycle onward is evaluated as CoO + xSeO2 + (1 ? x)Se + 4(x + 1)Li++ 4( x + 1)e? ? Co + (2x + 1)Li2O + Li2Se. The CoSeO3 microspheres show a high reversible capacity of 709 mA h g?1 for the 1400th cycle at a current density of 3 A g?1 and a high reversible capacity of 526 mA h g?1 even at an extremely high current density of 30 A g?1. 相似文献
996.
Jian Xie Xue‐Feng Cheng Xun Cao Jing‐Hui He Wei Guo Dong‐Sheng Li Zhichuan J. Xu Yizhong Huang Jian‐Mei Lu Qichun Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(49)
Conjugated coordination polymers have become an emerging category of redox‐active materials. Although recent studies heavily focus on the tailoring of metal centers in the complexes to achieve stable electrochemical performance, the effect on different substitutions of the bridging bonds has rarely been studied. An innovative tailoring strategy is presented toward the enhancement of the capacity storage and the stability of metal–organic conjugated coordination polymers. Two nanostructured d‐π conjugated compounds, Ni[C6H2(NH)4]n (Ni‐NH) and Ni[C6H2(NH)2S2]n (Ni‐S), are evaluated and demonstrated to exhibit hybrid electrochemical processes. In particular, Ni‐S delivers a high reversible capacity of 1164 mAh g?1, an ultralong stability up to 1500 cycles, and a fully recharge ability in 67 s. This tailoring strategy provides a guideline to design future effective conjugated coordination‐polymer‐based electrodes. 相似文献
997.
Chuanliang Wei Huifang Fei Yuan Tian Yongling An Guifang Zeng Jinkui Feng Yitai Qian 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(46)
Exploring flexible lithium‐ion batteries is required with the ever‐increasing demand for wearable and portable electronic devices. Selecting a flexible conductive substrate accompanying with closely coupled active materials is the key point. Here, a lightweight, flexible, and freestanding MXene/liquid metal paper is fabricated by confining 3 °C GaInSnZn liquid metal in the matrix of MXene paper without any binder or conductive additive. When used as anode for lithium‐ion cells, it can deliver a high discharge capacity of 638.79 mAh g?1 at 20 mA g?1. It also exhibits satisfactory rate capacities, with discharge capacities of 507.42, 483.33, 480.22, 452.30, and 404.47 mAh g?1 at 50, 100, 200, 500, and 1000 mA g?1, respectively. The cycling performance is obviously improved by slightly reducing the charge–discharge voltage range. The composite paper also has better electrochemical performance than liquid metal coated Cu foil. This study proposes a novel flexible anode by a clever combination of MXene paper and low‐melting point liquid metal, paving the way for next‐generation lithium‐ion batteries. 相似文献
998.
Yaru Liang Wei‐Hong Lai Zongcheng Miao Shu‐Lei Chou 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(5)
Clean energy has become an important topic in recent decades because of the serious global issues related to the development of energy, such as environmental contamination, and the intermittence of the traditional energy sources. Creating new battery‐related energy storage facilities is an urgent subject for human beings to address and for solutions for the future. Compared with lithium‐based batteries, sodium–ion batteries have become the new focal point in the competition for clean energy solutions and have more potential for commercialization due to the huge natural abundance of sodium. Nevertheless, sodium–ion batteries still exhibit some challenges, like inferior electrochemical performance caused by the bigger ionic size of Na+ ions, the detrimental volume expansion, and the low conductivity of the active materials. To solve these issues, nanocomposites have recently been applied as a new class of electrodes to enhance the electrochemical performance in sodium batteries based on advantages that include the size effect, high stability, and excellent conductivity. In this Review, the recent development of nanocomposite materials applied in sodium–ion batteries is summarized, and the existing challenges and the potential solutions are presented. 相似文献
999.
Carbon Necklace Incorporated Electroactive Reservoir Constructing Flexible Papers for Advanced Lithium–Ion Batteries
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Min Du Kun Rui Yuanqin Chang Yu Zhang Zhongyuan Ma Wenping Sun Qingyu Yan Jixin Zhu Wei Huang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(2)
Metal–organic frameworks (MOFs) and their derivatives with well‐defined structures and compositions show great potential for wide applications such as sensors, catalysis, energy storage, and conversion, etc. However, poor electric conductivity and large volume expansion are main obstacles for their utilization in energy storage, e.g., lithium–ion batteries and supercapacitors. Herein, a facile strategy is proposed for embedding the MOFs, e.g., ZIF‐67 and MIL‐88 into polyacrylonitrile fibers, which is further used as a template to build a 3D interconnected conductive carbon necklace paper. Owing to the unique structure features of good electric conductivity, interconnected frameworks, electroactive reservoir, and dual dopants, the obtained flexible electrodes with no additives exhibit high specific capacities, good rate capability, and prolonged cycling stability. The hollow dodecahedral ZIF‐67 derived carbon necklace paper delivers a high specific capacity of 1200 mAh g?1 and superior stability of more than 400 cycles without capacity decay. Moreover, the spindle‐like MIL‐88 derived carbon necklace paper shows a high reversible capacity of 980 mAh g?1. Their unique 3D interconnected structure and outstanding electrochemical performance pave the way for extending the MOF‐based interweaving materials toward potential applications in portable and wearable electronic devices. 相似文献
1000.
Se Youn Cho Minjee Kang Jaewon Choi Min Eui Lee Hyeon Ji Yoon Hae Jin Kim Cecilia Leal Sungho Lee Hyoung‐Joon Jin Young Soo Yun 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(17)
Na‐ion cointercalation in the graphite host structure in a glyme‐based electrolyte represents a new possibility for using carbon‐based materials (CMs) as anodes for Na‐ion storage. However, local microstructures and nanoscale morphological features in CMs affect their electrochemical performances; they require intensive studies to achieve high levels of Na‐ion storage performances. Here, pyrolytic carbon nanosheets (PCNs) composed of multitudinous graphitic nanocrystals are prepared from renewable bioresources by heating. In particular, PCN‐2800 prepared by heating at 2800 °C has a distinctive sp2 carbon bonding nature, crystalline domain size of ≈44.2 Å, and high electrical conductivity of ≈320 S cm?1, presenting significantly high rate capability at 600 C (60 A g?1) and stable cycling behaviors over 40 000 cycles as an anode for Na‐ion storage. The results of this study show the unusual graphitization behaviors of a char‐type carbon precursor and exceptionally high rate and cycling performances of the resulting graphitic material, PCN‐2800, even surpassing those of supercapacitors. 相似文献