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991.
PDP选址驱动芯片的HV-COMS器件设计   总被引:2,自引:0,他引:2  
设计出一种能与 0 .6μm的标准低压 CMOS工艺完全兼容的 HV-CMOS (High Voltage CMOS)结构 ,并提出了具体的工艺实现方法——单阱非外延工艺 ,该工艺能降低生产难度和成本。同时采用 TSUPREM-4对该结构进行工艺模拟 ,并用 MEDICI对该结构的电流 -电压和击穿等特性进行模拟。该结构的 HV-CMOS应用于 PDP(Plasma Display Panel)选址驱动芯片 ,能在 80 V、40 m A的工作要求下安全工作  相似文献   
992.
Al-Cu-Fe系初生准晶相凝固过程的电子显微分析   总被引:3,自引:0,他引:3  
采用包括金相(OM),粉末X射线衍射(XRD),扫描电子显微镜(SEM)观察和透射电子显微(TEM)分析等方法,研究了铸态Al592.Cu36.8Fe3.0Si1.0合金(700℃保温2.5h后水淬)的显微组织及相组成。发现铸锭中存在4种相:准晶I相,τ3相(或φ相),θ-Al2Cu相和η-AlCu相,凝固过程可描述为:初生晶是准晶Ⅰ相;在保温过程中发生包晶或共晶反应(L+i→τ3(或φ)或L→τ3(或φ)+i)形成的τ3相(或φ相),呈微畴结构;而剩余液体水淬形成θ-Al2Cu相和η-AlCu 相。  相似文献   
993.
王青 《通信技术》2002,(4):57-58
提出了WDM环形网络的几种保护方案,分析了利用1:1环路配置方式进行WDM光环形网络保护的实现方法,简单介绍APS在环保护中的应用。  相似文献   
994.
该文研究了一种在扩频分组无线网中适合2多媒体传输的MAC协议--CDMA/RTDMA。它在RTDMA的基础上,将基站可分配的资源从时隙扩展为码字-时隙,从而增加了系统的容量,更有效地支持多媒体业务的传输。文章分别通过M/M/n/m排队模型和相位过程来分析话音的丢包率和数据的延迟。通过数值计算和计算机仿真,相对于原有的RTDMA方式,这种新的MAC协议在网络负载较重的情况下,仍能保证多种业务的QoS要求。  相似文献   
995.
Considering the realistic teletraffic analysis in advanced telecommunication networks, the estimation of basic characteristics of arrival processes by empirical data is an important subject of current research. Using independent observations of the interarrival times between events and the mean numbers of events in intervals of fixed length, we propose methods to estimate the intensity of a nonhomogeneous arrival stream, particularly a Poisson process, and the renewal function of a renewal process. We formulate the estimation task as stochastically ill-posed problem and apply procedures for the stabilization of the estimates.  相似文献   
996.
To improve the robustness and reliability of wireless transmissions, two complementary link adaptation techniques are employed: adaptive modulation and coding (AMC) at the physical layer and hybrid automatic retransmission request (HARQ) at the medium access control layer. Because of their effectiveness in combating errors induced by the wireless channel, AMC and HARQ are now integral components of most emerging broadband wireless system standards, for example, LTE and WiMAX. Spectral efficiency (SE) as measured in bit per second per Hertz is one important parameter used to characterize a wireless system for comparison between different systems or between different configurations of the same system. This work provides a holistic approach of cross‐layer optimizations with the intent of maximizing SE by combining AMC and HARQ. It formulates closed‐form equations for calculating the average SE for wireless systems with the Rayleigh fading channel model. A new online algorithm is developed to optimize SE for both Rayleigh and non‐Rayleigh fading channel. Simulations using proven LTE model are performed to compare SE obtained from closed‐form equations and the developed algorithm for different system configurations. With the developed algorithm to determine how many retransmissions required in addition to the initial transmission in advance depending on the current wireless channel condition, the latency can be reduced up to 24 ms when sending the initial transmission and all of its retransmissions sooner than waiting for retransmission requests as is done previously. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
997.
填充函数方法是求解无约束的全局优化问题的重要方法,该方法在于构建具有性质良好、形式简单而且容易求解极小值的填充函数。文章按照填充函数的定义,构建了一个新的单参数填充函数,探究并且证明了该填充函数的填充性质和其他的必要性质。  相似文献   
998.
Recently, a new route to achieve 100% internal quantum efficiency white organic light‐emitting diodes (WOLEDs) is proposed by utilizing noble‐metal‐free thermally activated delayed fluorescence (TADF) emitters due to the radiative contributions of triplet excitons by effective reverse intersystem crossing. However, a systematic understanding of their reliability and internal degradation mechanisms is still deficient. Here, it demonstrates high performance and operational stable purely organic fluorescent WOLEDs consisting of a TADF assistant host via a strategic exciton management by multi‐interlayers. By introducing such interlayers, carrier recombination zone could be controlled to suppress the generally unavoidable quenching of long‐range triplet excitons, successfully achieving remarkable external quantum efficiency of 15.1%, maximum power efficiency of 48.9 lm W−1, and extended LT50 lifetime (time to 50% of initial luminance of 1000 cd m−2) exceeding 2000 h. To this knowledge, this is the first pioneering work for realizing high efficiency, low efficiency roll‐off, and operational stable WOLEDs based on a TADF assistant host. The current findings also indicate that broadening the carrier recombination region in both interlayers and yellow emitting layer as well as restraining exciplex quenching at carrier blocking interface make significant roles on reduced efficiency roll‐off and enhanced operational lifetime.  相似文献   
999.
The photothermoelectric (PTE) effect that originates from the temperature difference within thermoelectric materials induced by light absorption can be used as the mechanism for a light sensor in optoelectronic applications. In this work, a PTE‐based photodetector is reported using a spin thermoelectric structure consisting of CoFeB/Pt metallic bilayers and its signal enhancement achieved by incorporating a plasmonic structure consisting of Au nanorod arrays. The thermoelectric voltage of the bilayers markedly increases by 60 ± 10% when the plasmon resonance condition of the Au nanorods is matched to the wavelength of the incident laser. Full‐wave electromagnetic simulations reveal that the signal enhancement is due to the increase in light absorption and consequential local heating. Moreover, the alignment of the Au nanorods makes the thermoelectric voltages sensitive to the polarization state of the laser, thereby enabling the detection of light polarization. These results demonstrate the feasibility of a hybrid device utilizing plasmonic and spin‐thermoelectric effects as an efficient PTE‐based photodetector.  相似文献   
1000.
A new transparent p‐type oxide semiconductor (POS) is reported, Cu2SnS3‐Ga2O3, having high Hall mobility of 36.22 cm2 V−1s−1, and high work function of 5.17 eV. The existence of Cu2SnS3 and Ga2O3 phases in the film is confirmed by X‐ray photoelectron spectroscopy results and the Cu2SnS3 shows polycrystalline structure according to Raman spectrum and X‐ray diffraction analysis. The transparent Cu2SnS3‐Ga2O3 exhibits the carrier concentration of 5.86 × 1016 cm−3, and electrical resistivity of 1.94 Ω·cm. The transparent POS is applied to green quantum light‐emitting diodes (QLEDs) as a hole injection layer (HIL) because of its high work function. The QLED exhibits the maximum current efficiency of 51.72 cd A−1, power efficiency of 31.97 lm W−1, and external quantum efficiency (EQE) of 14.93%, which are much higher than the QLED using polyethylene dioxythophene:poly(styrenesulfonate) HIL exhibiting current efficiency of 42.66 cd A−1, power efficiency of 20.33 lm W−1, and EQE of 12.36%. The Cu2SnS3‐Ga2O3 developed in this work can be widely used as a transparent and conductive p‐type oxide for thin‐film devices.  相似文献   
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