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101.
Lithium–sulfur (Li–S) batteries are promising next-generation rechargeable batteries due to thier high energy density, low cost, and environmental friendliness. However, the extremely low electrical conductivity of sulfur and the dissolution of polysulfides limit their actual electrochemical performances, especially in the case of high sulfur mass loading. Here, a new strategy based on intrinsic point defects of materials is proposed to simultaneously enhance the electrical conductivity of active material and regulate the migration of polysulfides. Taking advantage of ultrathin and lightweight Bi2Te2.7Se0.3 (BTS) interlayers with high-density antisite defects on the separator surface, the Li–S battery with BTS interlayer shows a capacity of 756 mAh g−1 at 2C and a low capacity decay rate of 0.1% over 300 cycles. The BTS interlayer can not only enhance the active material utilization but also improve capacity retention. The defect engineering strategy accompanied with facile method is promising for the development of advanced Li–S batteries for practical application.  相似文献   
102.
As demands for electrochemical energy storage continue to rise, alternative electrochemistries to conventional Li-ion batteries become more appealing. Here, an intercalation-conversion hybrid cathode that combines intercalation-type VS2 with conversion-type sulfur chemistry to construct high performance solid-state lithium-sulfur batteries is reported. The layered VS2 nanomaterial features Li-ion transport channels, metallic conductivity, and active capacity contribution, all of which provide an ideal platform for the solid state S/Li2S redox couple to unlock its high gravimetric capacity. The S/VS2/Li3PS4 hybrid cathode composite is prepared by a facile, low-cost, and low-energy mechanical blending process. The S/VS2/Li3PS4|Li3PS4|Li/In (or Li) all-solid-state cell exhibits sulfur utilization of ≈85%, with a Coulombic efficiency of close to 100%. High areal capacity up to 7.8 mA h cm−2 with an active material loading (S/VS2) as high as 15.5 mg cm−2 is achieved.  相似文献   
103.
The practicality of aqueous zinc ion batteries (AZIBs) for large-scale energy storage is hindered by challenges associated with zinc anodes. In this study, a low-cost and multi-function electrolyte additive, cetyltrimethyl ammonium bromide (CTAB), is presented to address these issues. CTAB adsorbs onto the zinc anode surface, regulating Zn2+ deposition orientation and inhibiting dendrite formation. It also modifies the solvation structure of Zn2+ to reduce water reactivity and minimize side reactions. Additionally, CTAB optimizes key physicochemical parameters of the electrolyte, enhancing the stability of the electrode/electrolyte interface and promoting reversibility in AZIBs. Theoretical simulations combined with operando synchrotron radiation-based in situ Fourier transform infrared spectra and in situ electrochemical impedance spectra further confirm the modified Zn2+ coordination environment and the adsorption effect of CTAB cations at the anode/electrolyte interface. As a result, the assembled Zn-MnO2 battery demonstrates a remarkable specific capacity of 126.56 mAh g−1 at a high current density of 4 A g−1 after 1000 cycles. This work highlights the potential of CTAB as a promising solution for improving the performance and practicality of AZIBs for large-scale energy storage applications.  相似文献   
104.
Lithium (Li) metal is regarded as the most attractive anode material for high‐energy Li batteries, but it faces unavoidable challenges—uncontrollable dendritic growth of Li and severe volume changes during Li plating and stripping. Herein, a porous carbon framework (PCF) derived from a metal–organic framework (MOF) is proposed as a dual‐phase Li storage material that enables efficient and reversible Li storage via lithiation and metallization processes. Li is electrochemically stored in the PCF upon charging to 0 V versus Li/Li+ (lithiation), making the PCF surface more lithiophilic, and then the formation of metallic Li phase can be induced spontaneously in the internal nanopores during further charging below 0 V versus Li/Li+ (metallization). Based on thermodynamic calculations and experimental studies, it is shown that atomically dispersed zinc plays an important role in facilitating Li plating and that the reversibility of Li storage is significantly improved by controlled nanostructural engineering of 3D porous nanoarchitectures to promote the uniform formation of Li. Moreover, the MOF‐derived PCF does not suffer from macroscopic volume changes during cycling. This work demonstrates that the nanostructural engineering of porous carbon structures combined with lithiophilic element coordination would be an effective approach for realizing high‐capacity, reversible Li‐metal anodes.  相似文献   
105.
Practical applications of high gravimetric and volumetric capacity anodes for next‐generation lithium‐ion batteries have attracted unprecedented attentions, but still faced challenges by their severe volume changes, rendering low Coulombic efficiency and fast capacity fading. Nano and void‐engineering strategies had been extensively applied to overcome the large volume fluctuations causing the continuous irreversible reactions upon cycling, but they showed intrinsic limit in fabrication of practical electrode condition. Achieving high electrode density is particularly paramount factor in terms of the commercial feasibility, which is mainly dominated by the true density and tapping density of active material. Herein, based on finite element method calculation, micron‐sized double passivation layered Si/C design is introduced with restrictive lithiation state, which can withstand the induced stress from Li insertion upon repeated cycling. Such design takes advantage in structural integrity during long‐term cycling even at high gravimetric capacity (1400 mAh g?1). In 1 Ah pouch‐type full‐cell evaluation with high mass loading and electrode density (≈3.75 mAh cm?2 and ≈1.65 g cm?3), it demonstrates superior cycle stability without rapid capacity drop during 800 cycles.  相似文献   
106.
王蕊 《电子器件》2021,44(1):225-230
为了实现对动力锂电池内阻的高精度检测,通过对锂电池内部结构和工作原理进行分析,建立了等效电路模型,并采用交流注入法设计了电池内阻在线智能检测装置。将微小的交变激励电流信号施加在电池两端,同时利用在FPGA平台上设计的正交锁相放大电路测量电池两端产生的响应电压信号,并通过引入圆周模式的CORDIC算法实现矢量运算,大幅提升了数据处理速度,最后根据欧姆定律计算出电池内阻的阻抗幅值和相位角。实验结果表明:设计的内阻智能检测装置能够方便测量出电池在各频段的阻抗谱,且具有较高的测量精度和稳定度,平均误差仅为0.231%,最大偏差也仅为0.452%,可为新能源汽车动力电池的健康诊断提供可靠的技术保障。  相似文献   
107.
High performance flexible batteries are essential ingredients for flexible devices. However, general isolated flexible batteries face critical challenges in developing multifunctional embodied energy systems, owing to the lack of integrative design. Herein, inspired by scales in creatures, overlapping flexible lithium-ion batteries (FLIBs) consisting of energy storage scales and connections using LiNi0.5Co0.2Mn0.3O2 (NCM523) and graphite electrodes are presented. The scale-dermis structure ensures a high energy density of 374.4 Wh L−1 as well as a high capacity retention of 93.2% after 200 charge/discharge cycles and 40 000 bending times. A variable stiffness property is revealed that can be controlled by battery configurations and deformation modes. Furthermore, the overlapping FLIBs can be housed directly into the architecture of several flexible devices, such as robots and grippers, allowing to create multifunctionalities that go far beyond energy storage and include load-bearing and variable flexibility. This study broadens the versatility of FLIBs toward energy storage structure engineering of flexible devices.  相似文献   
108.
Regarding the complex properties of various cations, the design of aqueous batteries that can simultaneously store multi-ions with high capacity and satisfactory rate performance is a great challenge. Here an amorphization strategy to boost cation-ion storage capacities of anode materials is reported. In monovalent (H+, Li+, K+), divalent (Mg2+, Ca2+, Zn2+) and even trivalent (Al3+) aqueous electrolytes, the capacity of the resulting amorphous MoOx is more than quadruple than that of crystalline MoOx and exceeds those of other reported multiple-ion storage materials. Both experimental and theoretical calculations reveal the generation of ample active sites and isotropic ions in the amorphous phase, which accelerates cation migration within the electrode bulk. Amorphous MoOx can be coupled with multi-ion storage cathodes to realize electrochemical energy storage devices with different carriers, promising high energy and power densities. The power density exceeded 15000 W kg−1, demonstrating the great potential of amorphous MoOx in advanced aqueous batteries.  相似文献   
109.
The practical application of spinel-type lithium titanate Li4Ti5O12 (LTO) lithium-ion batteries is hindered by its poor conductivity and relatively low capacity. To address these issues, an LTO/reduced graphene oxide (rGO)/SnO2 is synthesized via an in situ electrostatic self-assembly and hydrothermal reduction process. Density function theory (DFT) simulations are conducted to understand the geometrical structures of these composites and the energy storage mechanisms. The DFT results confirm that the introduction of rGO and SnO2 to LTO increases the overall conductivity, improves the structure stability, and increases Li-ion diffusion speed.  相似文献   
110.
In the development of all-solid-state lithium batteries (ASSLB), progress is made with solid-state electrolytes; however, challenges regarding compatibility and stability still exist with solid electrodes. These issues result in a low battery capacity and short cycle life, which limit the commercial application of ASSLBs. This review summarizes the recent research progress on solid-state electrodes in ASSLBs including the solid–solid interface phenomena such as the interface between electrode materials and electrolytes. The mechanical stability problems in solid electrodes, including fracture, brittleness, and deformation of electrode materials, are also discussed, and corresponding methods to measure the solid electrode stress are provided. In addition, strategies for mitigating stress-related issues are examined. Finally, the fabrication process of solid electrodes is introduced and their future developments, including the exploration of new electrode materials and the design of more intelligent electrode structures, are proposed.  相似文献   
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