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991.
Laure Biniek Christos L. Chochos Georges Hadziioannou Nicolas Leclerc Patrick Lvêque Thomas Heiser 《Macromolecular rapid communications》2010,31(7):651-656
A series of donor‐acceptor alternated conjugated copolymers, composed of thiophene, bithiophene, thieno[3,2‐b]thiophene, and 2,1,3‐benzothiadiazole units and differing from each other by the nature and the number of 3‐alkylthiophene in the backbone, have been synthesized by Stille cross‐coupling polymerization. The material's optical and electrochemical properties, in solution and in thin films, have been investigated using UV‐Visible absorption and cyclic voltammetry. Bulk heterojunction solar cells using blends of the newly synthesized copolymers, as electron donor, and C60‐PCBM or C70‐PCBM, as electron transporting material, have been elaborated. A maximum power conversion efficiency of 1.8% is achieved with a 1:4 PPBzT2‐C12:C70‐PCBM weight ratio.
992.
Reduction of driving voltage in organic light-emitting diodes with molybdenum trioxide in CuPc/NPB interface 总被引:2,自引:0,他引:2
Ye Zou Zhaoyue Lv Denghui Xu Yuehong Yin Yongsheng Wang 《Journal of luminescence》2010,130(6):959-962
A novel structure of organic light-emitting diode was fabricated by inserting a molybdenum trioxide (MoO3) layer into the interface of hole injection layer copper phthalocyanine (CuPc) and hole transport layer N,N′-diphenyl-N,N′-bis(1-napthyl-phenyl)-1,1′-biphenyl-4,4′-diamine (NPB). It has the configuration of ITO/CuPc(10 nm)/MoO3(3 nm)/NPB(30 nm)/ tris-(8-hydroxyquinoline) aluminum (Alq3)(60 nm)/LiF(0.5 nm)/Al. The current density-voltage-luminance (J-V-L) performances show that this structure is beneficial to the reduction of driving voltage and the enhancement of luminance. The highest luminance increased by more than 40% compared to the device without hole injection layer. And the driving voltage was decreased obviously. The improvement is ascribed to the step barrier theory, which comes from the tunnel theory. The power efficiency was also enhanced with this novel device structure. Finally, “hole-only” devices were fabricated to verify the enhancement of hole injection and transport properties of this structure. 相似文献
993.
994.
A two-dimensional analytical modeling for channel potential and threshold voltage of short channel triple material symmetrical gate Stack(TMGS) DG-MOSFET 下载免费PDF全文
Shweta Tripathi 《中国物理 B》2016,25(10):108503-108503
In the present work, a two-dimensional(2D) analytical framework of triple material symmetrical gate stack(TMGS)DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along with triple material gate having different work functions and symmetrical gate stack structure, showcases substantial betterment in quashing short channel effects to a good extent. The device functioning amends in terms of improved exemption to threshold voltage roll-off, thereby suppressing the short channel effects. The encroachments of respective device arguments on the threshold voltage of the proposed structure are examined in detail. The significant outcomes are compared with the numerical simulation data obtained by using 2D ATLAS~(TM) device simulator to affirm and formalize the proposed device structure. 相似文献
995.
在研究分析弛豫SiGe衬底上的应变Si 沟道nMOSFET纵向电势分布的基础上,建立了应变Si nMOSFET阈值电压模型,并利用该模型对不同的器件结构参数进行仿真,获得了阈值电压与SiGe层掺杂浓度和Ge组分的关系、阈值电压偏移量与SiGe层中Ge组分的关系、阈值电压与应变Si层掺杂浓度和厚度的关系. 分析结果表明:阈值电压随SiGe层中Ge组分的提高而降低,随着SiGe层的掺杂浓度的提高而增大;阈值电压随应变Si层的掺杂浓度的提高而增大,随应变Si层厚度增大而增大. 该模型为应变Si 器件阈值电压设计
关键词:
应变硅
阈值电压
电势分布
反型层 相似文献
996.
Nebojsa M. Djordjevic Fabrice Houdiere Guido Lerch Fiona Fitzpatrick 《Journal of separation science》1999,22(8):443-448
Temperature and voltage programming modes were utilized to optimize selectivity and increase the eluting rate of strongly retained compounds in micellar electrokinetic chromatography. Separations obtained by applying temperature, voltage, and a simultaneous combination of temperature and voltage gradient in micellar electrokinetic capillary chromatography were compared with separations performed under isothermal and constant voltage conditions. A complete separation of all the constituents of the test mixture was only achieved in the temperature programming run and in a combination of temperature and voltage programming modes. Simultaneous variations of column temperature and applied voltage during a separation run, yielded a 30% reduction in the total analysis time when compared to a temperature gradient alone. Temperature programming and voltage programming modes may be the gradient methods of choice because of the considerable technical difficulties involved in performing linear solvent gradient elution in micellar electrokinetic chromatography. 相似文献
997.
针对一种用于快前沿直线脉冲变压器驱动源的多间隙气体开关,设计了针式和孔式两种预电离触发结构,获得了两种预电离结构下开关的自击穿特性和触发特性。实验结果表明:增加预电离针后,开关静态特性没有明显变化,开关自击穿电压平均值变化幅度小于3%;开关触发特性明显改善,开关工作电压150 kV、触发电压60 kV时,触发抖动减小约20%,触发阈值降低5~10 kV。对于针式预电离结构,实验研究了不同触发电压、工作气压、电离间隙距离时紫外光强度的变化规律,结果表明在电离间隙距离1.5~3.0 mm时,开关触发抖动小于2.0 ns,预电离效果明显。 相似文献
998.
A novel structure is proposed for doubling the vertical breakdown voltage of silicon-on-insulator(SOI) devices. In this new structure, the conventional buried oxide(BOX) in an SOI device is split into two sections: the source-section BOX and the drain-section BOX. A highly-doped Si layer, referred to as a non-depletion potential-clamped layer(NPCL), is positioned under and close to the two BOX sections. In the split BOXes and the Si region above the BOXes, the blocking voltage(BV) is divided into two parts by the NPCL. The voltage in the NPCL is clamped to be nearly half of the drain voltage. When the drain voltage approaches a breakdown value, the voltage sustained by the source-section BOX and the Si region under the source are nearly the same as the voltage sustained by the drain-section BOX and the Si region under the drain. The vertical BV is therefore almost doubled. The effectiveness of this new structure was verified for a P-channel SOI lateral double-diffused metal-oxide semiconductor(LDMOS) and can be applied to other high-voltage SOI devices. The simulation results show that the BV in an NPCL P-channel SOI LDMOS is improved by 55% and the specific on-resistance(Ron,sp) is reduced by 69% in comparison to the conventional structure. 相似文献
999.
针对EAST磁体电源等非线性负载产生低次谐波(75~125 Hz)难以治理的问题,提出注入式混合有源滤波的方案。基于EAST低次谐波实验平台,对注入式混合有源电力滤波装置的拓扑结构与滤波原理进行了研究; 同时采用一种降低直流侧中点电位波动的三电平空间电压矢量调制算法,并给出基本矢量作用时间的求取方法; 对该方案及算法进行了仿真与实验验证,仿真与实验结果具有很高的一致性,证明该方案能有效抑制EAST磁体电源运行中产生的低次谐波及其谐振放大。 相似文献
1000.