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191.
激光二极管抽运的Nd:YVO4GaAs被动调Q激光器研究   总被引:6,自引:0,他引:6  
李平  王继扬等 《光学学报》2002,22(3):98-302
报道了激光二极管抽运Nd:YVO4半导体材料GaAs被动调Q激光器运转。测量了不同透过率输出镜条件下,输出调Q脉冲的宽度,能量及冲重复率。在抽运功率为4W时,得到了脉宽为30ns、能量为8μJ、重复率为60KHZ的稳定的调Q脉冲。还就GaAs调Q机理进行了理论研究并对实验中的一些现象进行了分析讨论。  相似文献   
192.
含氮磷酸锂薄膜在空气中的稳定性   总被引:1,自引:0,他引:1  
利用射频(RF)磁控溅射方法制备了含氮磷酸锂(LiPON)薄膜. 采用SEM、XRD、XPS等技术以及交流阻抗法和电位线性扫描法, 研究了空气湿度对LiPON薄膜形貌、组成和性能的影响. 结果表明, LiPON薄膜在湿度为40%的空气环境中放置24 h后, 将发生明显的水解反应, 使LiPON薄膜表面形貌变得疏松、局部突起; PH3和NH3的产生, 使薄膜中磷元素和氮元素含量减少, 而Li2CO3的生成, 则使薄膜中碳元素和氧元素含量有明显的增加. LiPON电解质薄膜形貌和组成的变化, 造成了薄膜电化学性能的严重恶化.  相似文献   
193.
采用Fe~(3+)离子交联的方法制备氧化石墨烯水凝胶,经化学还原制备出一种新型的三维多孔石墨烯薄膜材料命名为rGO-Fe;通过电化学聚合法在rGO-Fe基底上进一步制备了一种三维多孔石墨烯/含钛共轭聚合物复合薄膜材料,命名为r GO-Fe/P(EDOT:P3C)-1-Ti。作为一种新型复合薄膜材料,rGO-Fe/P(EDOT:P3C)-1-Ti较rGO-Fe具有更好的抗拉伸性能,平均厚度为3μm的rGO-Fe/P(EDOT:P3C)-1-Ti薄膜,可承受载荷拉力0.97 N,优于相同厚度的rGO-Fe薄膜(0.76 N)。将rGO-Fe/P(EDOT:P3C)-1-Ti薄膜作为自支撑电极制备了柔性全固态超级电容器,表现出优良的电容性能,且在弯折状态下仍能正常工作。当电流密度为0.1 A?g~(-1)时,该柔性全固态超级电容器的质量比容量为71.13?F?g~(-1),面积比容量为101 mF?cm~(-2),当电流密度为0.6 A?g~(-1)时,其质量比容量为18.14 F?g~(-1),面积比容量为25.8 mF?cm~(-2)。  相似文献   
194.
A compact PbS quantum-dot thin film was prepared using the combination of TiO2 nanorod arrays and 1, 2-ethanedithiol following the spin-coating assisted successive ionic layer absorption and reaction procedure. Solar cells with the novel structure of FTO/compact PbS quantum-dot thin film sensitized TiO2 nanorod arrays/spiro-OMeTAD/Au were assembled. Subsequently, the influence of the length of TiO2 nanorod arrays on the photovoltaic performance of all-solid-state compact PbS quantum-dot thin film sensitized solar cells was evaluated. The corresponding solar cells having TiO2 nanorod array lengths of 290, 540, and 1040 nm achieved photoelectric conversion efficiencies (PCE) of 2.02%, 4.81%, and 1.95%, respectively. These results reveal that in order to achieve high PCE values with the all-solid-state quantum dot sensitized solar cells, it is very important to balance the hole diffusion length with the loading amount of quantum-dots.  相似文献   
195.
王东浩  晏鹤凤  龚正良 《电化学》2021,27(4):388-395
使用硫化物固体电解质的全固态锂硫电池由于多硫化物不溶于硫化物固体电解质及硫化物电解质不可燃的特性,得以完全避免穿梭效应并显著提高了电池的安全性能而被认为是极具潜力的下一代储能电池。如何建立并平衡复合正极中离子/电子导电网络且维持复合正极中较高活性物质含量对于全固态锂硫电池至关重要。本文以单质硫为活性物质研究了复合导电添加剂对全固态锂硫电池性能的影响,发现以乙炔黑(AB)为导电碳材料明显优于Super P和Ketjen Black;优化复合正极的组成,发现硫:乙炔黑:固体电解质的质量比为40:20:40时,全固态锂硫电池在室温和60℃下均具有良好的电化学性能。  相似文献   
196.
采用MOSFET半导体固态开关作为主放电开关取代气体开关、高压二极管替代充电电阻的技术方法,设计了一种基于功率MOSFET固态开关的纳秒级全固态脉冲源。设计的脉冲源主开关级数共5级,每级主开关分别由5只功率MOSFET半导体固态开关器件串联组成,开关通断控制采用脉冲隔离变压器同步驱动方式。在重复频率1 Hz~1 kHz、充电电压4 kV、负载阻抗为1 k条件下,可实现输出幅度大于20 kV、前沿小于10 ns且脉宽大于100 ns的高压快脉冲。通过实验结果验证了所采用的设计原理及方法的可行性,并给出了单次和重复频率(1 kHz)触发信号作用下全固态脉冲源输出的实验结果。  相似文献   
197.
介绍了利用沉积在增透镜上的石墨烯薄膜作为可饱和吸收体、808 nm激光二极管端面泵浦Nd∶YVO4晶体的1 064 nm连续锁模激光输出特性。采用W型折叠谐振腔结构,在808 nm泵浦功率为8.0 W时,有稳定的连续锁模脉冲输出,平均输出功率达到185 mW;当抽运功率增加到16.0 W时,获得了中心波长1 063.4 nm、脉冲宽度为518 fs、重复频率为66.7 MHz、最大平均输出功率为323 mW的百飞秒量级超短脉冲激光输出。实验结果表明:石墨烯具有优良的可饱和吸收性,在1 064 nm波段能够实现高功率、百飞秒量级连续锁模脉冲激光输出。  相似文献   
198.
LiCo0.8M0.2O2 (M=Ni,Zr) films were fabricated by radio frequency sputtering deposition combined with conventional annealing methods. The structures of the films were characterized with X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM) techniques. It was shown that the 700 ±C-annealed LiCo0.8M0.2O2 has an @-NaFeO2-like layered structure. All-solid-state thin-film batteries (TFBs) were fabricated with these films as the cathode and their electrochemical performances were evaluated. It was found that doping of electrochemically active Ni and inactive Zr has different effects on the structural and electrochemical properties of the LiCoO2 cathode films. Ni doping increases the discharge capacity of the film while Zr doping improves its cycling stability.  相似文献   
199.
Owing to the serious energy crisis and environmental problems caused by fossil energy consumption, development of high-energy-density batteries is becoming increasingly significant to satisfy the rapidly growing social demands. Lithium-ion batteries have received widespread attention because of their high energy densities and environmental friendliness. At present, they are widely used in portable electronic devices and electric vehicles. However, security aspects need to be addressed urgently. Substantial advances in liquid electrolyte-based lithium-ion batteries have become a performance bottleneck in the recent years. Traditional lithium-ion batteries use organic liquids as electrolytes, but the flammability and corrosion of these electrolytes considerably limit their development. Continuous growth of lithium dendrites can pierce the separator, leading to electrolyte leakage and combustion, which is a serious safety hazard. Replacement of organic electrolytes with solid-state electrolytes is one of the promising solutions for the development of next-generation energy storage devices, because they have high energy densities and are safe. Solid electrolytes can remarkably alleviate the safety hazards involved in the use of traditional liquid-based lithium-ion batteries. In addition, the composite of solid-state electrolytes and lithium metal is expected to result in a higher energy density. However, due to the lack of fluidity of the solid electrolytes, problems such as limited solid-solid contact area and increased impedance at the interface when solid-state electrolytes are in contact with electrodes must be solved. The localized and buried interface is a major drawback that restricts the electrochemical performance and practical applications of the solid-state batteries. Fabrication of a stable interface between the electrodes and solid-state electrolyte is the main challenge in the development of solid-state lithium metal batteries. All these aspects are critical to the electrochemical performance and safety of the solid-state batteries. Current research mainly focuses on addressing the problems related to the solid-solid interface in solid-state batteries and improving the electrochemical performance of such batteries. In this review, we comprehensively summarize the challenges in the fabrication of solid-state batteries, including poor chemical and electrochemical compatibilities and mechanical instability. Research progress on the improvement strategies for interface problems and the advanced characterization methods for the interface problems are discussed in detail. Meanwhile, we also propose a prospect for the future development of solid-state batteries to guide the rational designing of next-generation high-energy solid-state batteries. There are many critical problems in solid-state batteries that must be fully understood. With further research, all-solid-state batteries are expected to replace the traditional liquid-based lithium-ion batteries and become an important system for a safe and reliable energy storage.  相似文献   
200.
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