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991.
功率场效应管在线性功率放大器中的应用 总被引:1,自引:0,他引:1
论述了功率场效应管的线性应用。实验结果表明,应用功率场效应管的功率放大器比一般晶体管放大器电路更简单,特性更好。 相似文献
992.
将LED照明和可见光通信技术结合,构建出基于室内实时以太网视频传输的可见光通信系统.系统发送端利用高速场效应管直接驱动控制光源,并结合以太网数据特征,采用UDP传输协议,对信号进行4B:5B和非归零反相编码(NRZI)相结合的编码.接收端采用基于FPGA的数字锁相环技术对光探测信号的时钟和数据进行恢复和提取.系统实现了室内1m距离的实时以太网视频可见光通信传输,促进了可见光通信技术的实用化. 相似文献
993.
994.
随着器件尺寸的缩小,寄生电阻对器件性能的影响不可忽视,为准确预测器件的寄生电阻并了解器件参数对寄生电阻的影响,需要有准确的寄生电阻模型。该文分析了短沟道寄生电阻模型,研究了短沟道寄生电阻模型在栅压较小时与模拟结果存在较大误差的原因,并对模型进行了改进。最后分析了器件参数对寄生电阻的影响,提出未来减小寄生电阻需要和可能采取的措施。 相似文献
995.
利用负反馈技术设计了一款基于CMOS亚阈值MOS器件的低压高性能CMOS基准源电路。基于SMIC 0.18μm标准CMOS工艺,Cadence Spectre仿真结果表明:所设计的基准电路能在0.8V电压下稳定工作,输出380.4mV的基准电压;在1kHz频率范围内,电源噪声抑制比为-56.5dB;在5℃到140℃范围内,温度系数6.25ppm/℃。 相似文献
996.
Kamran AbidAuthor VitaeAli Z. KhokharAuthor Vitae Faiz RahmanAuthor Vitae 《Sensors and actuators. A, Physical》2011,172(2):434-439
We describe a metal-oxide silicon (MOS) phototransistor that relies on a novel lateral doping scheme that creates a p-i-n junction configuration for light detection. This is essentially a hybrid device with the horizontal structure of a p-i-n diode and the vertical structure of a MOS field-effect transistor. The lateral p-i-n diode detects light whereas the gate can be used to change the current flowing through the device; making it appear as a MOSFET. This feature makes it easy to integrate it with other conventional MOSFETs on a CMOS process flow. The device shows high optical responsivities that persist to wavelengths in the near-ultraviolet region. The fabrication of the device as well as its electrical and optical characteristics is described. 相似文献
997.
T. LalinskýAuthor VitaeG. VankoAuthor Vitae M. ValloAuthor Vitae M. Dr?íkAuthor VitaeJ. BrunckoAuthor Vitae J. JakovenkoAuthor VitaeV. KutišAuthor Vitae I. RýgerAuthor VitaeŠ. Haš?íkAuthor Vitae M. HusákAuthor Vitae 《Sensors and actuators. A, Physical》2011,172(2):386-391
We report on a piezoelectric response investigation of AlGaN/GaN circular high electron mobility transistor (C-HEMT) based ring gate capacitor as a new stress sensor device to be potentially applied for dynamic high-pressure sensing. A ring gate capacitor of C-HEMT with an additional ZnO gate interfacial layer was used to measure the changes in the piezoelectric charge induced directly by the variation of piezoelectric polarization of both gate piezoelectric layers (AlGaN, ZnO) for harmonic loading at different excitation frequences. Our experimental results show that about 10 nm thick piezoelectric ZnO layer grown on ring gate/AlGaN interface of C-HEMT can yield almost a 60% increase in the piezoelectric detection sensitivity of the device due to its higher piezoelectric coefficient. A three-dimensional CoventorWare simulation is carried out to confirm the increase in the measured piezoelectric response of ZnO based ring gate capacitor of C-HEMT. 相似文献
998.
R. PearceAuthor Vitae T. IakimovM. AnderssonAuthor Vitae L. HultmanAuthor VitaeA. Lloyd SpetzAuthor Vitae R. YakimovaAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):451-455
Epitaxially grown single layer and multi layer graphene on SiC devices were fabricated and compared for response towards NO2. Due to electron donation from SiC, single layer graphene is n-type with a very low carrier concentration. The choice of substrate is demonstrated to enable tailoring of the electronic properties of graphene, with a SiC substrate realising simple resistive devices tuned for extremely sensitive NO2 detection. The gas exposed uppermost layer of the multi layer device is screened from the SiC by the intermediate layers leading to a p-type nature with a higher concentration of charge carriers and therefore, a lower gas response. The single layer graphene device is thought to undergo an n-p transition upon exposure to increasing concentrations of NO2 indicated by a change in response direction. This transition is likely to be due to the transfer of electrons to NO2 making holes the majority carriers. 相似文献
999.
Byung Hwan ChuAuthor VitaeC.F. LoAuthor Vitae Justin NicolosiAuthor VitaeC.Y. ChangAuthor Vitae Victor ChenAuthor VitaeW. StrupinskiAuthor Vitae S.J. PeartonAuthor VitaeF. RenAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(2):500-503
The characteristics of hydrogen detection using epitaxial graphene covered with platinum are reported. The multi-layered graphene was grown by chemical vapor deposition (CVD) on a Si-polar 4H-SiC substrate. Surface morphology was characterized by scanning electron and atomic force microscopy. Current-voltage measurements and real-time monitoring of the current flow through the graphene/platinum device were used to confirm the response to hydrogen gas. The background temperature was varied from room temperature to 175 °C in order to measure the activation energy of hydrogen detection. 相似文献
1000.