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991.
992.
Sangwoo Han Neeraj Lal Chang-Ho Lee Matinpour B. Laskar J. 《Solid-State Circuits, IEEE Journal of》2001,36(9):1360-1364
We present a C-band monolithic microwave integrated circuit (MMIC) transmitter module development for multichannel RF/optical subcarrier multiplexed (OSCM) communication applications. The C-band MMIC transmitter module consists of one fully monolithic four-channel OSCM transmitter IC and four coupled-line filters. This MMIC is designed and implemented in a commercial GaAs MESFET process and coupled line bandpass filters are fabricated on the module board. We present the design and performance of the first fully monolithic IC transmitter module for OSCM packet switched applications 相似文献
993.
Xiao-Zhao Zhu Yuan-Yuan Han Yuan Liu Kai-Qun Ruan Mei-Feng Xu Zhao-Kui Wang Jian-Sheng Jie Liang-Sheng Liao 《Organic Electronics》2013,14(12):3348-3354
There are many challenges for a direct application of graphene as the electrodes in organic electronics due to its hydrophobic surfaces, low work function (WF) and poor conductance. The authors demonstrate a modified single-layer graphene (SLG) as the anode in organic light-emitting diodes (OLEDs). The SLG, doped with the solution-processed titanium suboxide (TiOx) and poly(3,4-ethylenedio-xythiophene)/poly(styrene sulfonic acid) (PEDOT:PSS), exhibits excellent optoelectronic characteristics with reduced sheet resistance (Rsq), increased work function, as well as over 92% transmittance in the visible region. It is notable that the Rsq of graphene decreased by ∼86% from 628 Ω/sq to 86 Ω/sq and the WF of graphene increased about 0.82 eV from 4.30 eV to 5.12 eV after a modification by using the TiOx–PEDOT:PSS double interlayers. In addition, the existence of additional TiOx and PEDOT:PSS layers offers a good coverage to the PMMA residuals on SLG, which are often introduced during graphene transfer processes. As a result, the electrical shorting due to the PMMA residues in the device can be effectively suppressed. By using the modified SLG as a bottom anode in OLEDs, the device exhibited comparable current efficiency and power efficiency to those of the ITO based reference OLEDs. The approach demonstrated in this work could potentially provide a viable way to fabricate highly efficient and flexible OLEDs based on graphene anode. 相似文献
994.
D. L. Hibbard R. W. Chuang Y. S. Zhao C. L. Jensen H. P. Lee Z. J. Dong R. Shih M. Bremser 《Journal of Electronic Materials》2000,29(3):291-296
In this paper, we describe the change in barrier heights (ϕB) and ideality factors (n) of Ni/Au contacts to p-GaN determined from current-voltage measurements as a result of (a) rapid
thermal annealing between 400–700°C under flowing nitrogen, and (b) testing at temperatures of 20–300°C. The lowest barrier
height and ideality factor values were obtained from samples annealed at 500–600°C. These results provide supporting evidence
that thermal processing helps to remove contaminants at the contact-GaN interface, thus decreasing effective barrier height
and consequently, contact resistance. 相似文献
995.
本文主要介绍一种便于在微机上运行的耦合腔行波管综合计算程序 ,尽可能详细地给出了有关的计算公式 ,并对所采用的图形坐标显示系统和简易数据库系统进行了简要介绍。 相似文献
996.
Wei-Der Chang Rey-Chue Hwang Jer-Guang Hsieh 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2002,32(4):517-522
This paper presents a control strategy that incorporates an auto-tuning neuron into the sliding mode control (SMC) in order to eliminate the high control activity and chattering due to the SMC. The main difference between the auto-tuning neuron and the general one is that a modified hyperbolic tangent function with adjustable parameters is employed. In this proposed control structure, an auto-tuning neuron is then used as the neural controller without any connection weights.. The control law will be switched from the sliding control to the neural control, when the state trajectory of system enters in some boundary layer. In this way, the chattering phenomenon will not occur. The results of numerical simulations are provided to show the control performance of our proposed method. 相似文献
997.
Non‐Volatile Polymer Electroluminescence Programmable with Ferroelectric Field‐Induced Charge Injection Gate 下载免费PDF全文
Ju Han Lee Beomjin Jeong Sung Hwan Cho Eui Hyuk Kim Cheolmin Park 《Advanced functional materials》2016,26(30):5391-5399
Electroluminescence (EL) of organic and polymeric fluorescent materials programmable in the luminance is extremely useful as a non‐volatile EL memory with the great potential in the variety of emerging information storage applications for imaging and motion sensors. In this work, a novel non‐volatile EL memory in which arbitrarily chosen EL states are programmed and erased repetitively with long EL retention is demonstrated. The memory is based on utilizing the built‐in electric field arising from the remnant polarization of a ferroelectric polymer which in turn controls the carrier injection of an EL device. A device with vertically stacked components of a transparent bottom electrode/a ferroelectric polymer/a hole injection layer/a light emitting layer/a top electrode successfully emits light upon alternating current (AC) operation. Interestingly, the device exhibits two distinctive non‐volatile EL intensities at constant reading AC voltage, depending upon the programmed direct current (DC) voltage on the ferroelectric layer. DC programmed and AC read EL memories are also realized with different EL colors of red, green and blue. Furthermore, more than four distinguishable EL states are precisely addressed upon the programmed voltage input each of which shows excellent EL retention and multiple cycle endurance of more than 105 s and 102 cycles, respectively. 相似文献
998.
999.
Jaesik Yoon Hyejung Choi Dongsoo Lee Ju-Bong Park Joonmyoung Lee Dong-Jun Seong Yongkyu Ju Man Chang Seungjae Jung Hyunsang Hwang 《Electron Device Letters, IEEE》2009,30(5):457-459
We have investigated a Cu-doped MoOx/GdOx bilayer film for nonvolatile memory applications. By adopting an ultrathin GdOx layer, we obtained excellent device characteristics such as resistance ratio of three orders of magnitude, uniform distribution of set and reset voltages, switching endurance up to 104 cycles, and ten years of data retention at 85degC. By adopting bilayer films of Cu-doped MoOx/GdOx, a local filament was formed by a two-step process. Improved memory characteristics can be explained by the formation of nanoscale local filament in the ultrathin GdOx layer. 相似文献
1000.