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1.
《Physics letters. A》2020,384(1):126039
Different from the conventional Rydberg antiblockade (RAB) regime that either requires weak Rydberg-Rydberg interaction (RRI), or compensates the RRI-induced energy shift by introducing off-resonant interactions, we show that RAB regime can be achieved by resonantly driving the transitions between ground state and Rydberg state under strong RRI. The Rabi frequencies are of small amplitude and time-dependent harmonic oscillation, which plays a critical role for the presented RAB. The proposed unconventional RAB regime is used to construct high-fidelity controlled-Z (CZ) gate and controlled-not (CNOT) gate in one step. Each atom requires single external driving. And the atomic addressability is not required for the presented unconventional RAB, which would simplify experimental complexity and reduce resource consumption.  相似文献   
2.
Solid-stated smart polymers responsive to external stimuli have attracted much attention for potential application in the field of photoelectron devices, logic gates, sensor, data storage and security. However, it is a bigger challenge for polymers than that for small molecules in solid state to acquire stimuli-responsive properties, because polymers with high molecular weight are not as easy to change the packing structure as small molecules under external stimulation. Here, a D-A type alternating copolymer PTMF-o containing 3,4-bisthienylmaleimide(A unit) and fluorene(D unit) is designed and synthesized. Upon irradiation of sunlight, PTMF-o film exhibits a photo-response with the color altering from purple to colorless. It is attributed to the structure of copolymer transformed from ring-opening form(PTMF-o) to ring-closure form(PTMF-c), resulting from the oxidative photocyclization of 3,4-bisthienylmaleimide unit. Consequently, the ability of charge transfer(CT) from fluorene to 3,4-bisthienylmaleimide unit in PTMF-o can be easily weakened by light stimuli. PTMF-o film displays a WORM-type resistive storage performance for the strong CT. Interestingly, after exposure, the electrical memory behavior in situ transfers into FLASH type, due to weak CT in PTMF-c. PTMF-o film can also be employed as smart material to construct NAND and NOR logic gates by using light as input condition. The work provides a simple way to modify the electronic properties of polymers and realize stimuli-response in solid states.  相似文献   
3.
In this work, an analytical model of gate-engineered junctionless surrounding gate MOSFET (JLSRG) has been proposed to uncover its potential benefit to suppress short-channel effects (SCEs). Analytical modelling of centre potential for gate-engineered JLSRG devices has been developed using parabolic approximation method. From the developed centre potential, the parameters like threshold voltage, surface potential, Electric Field, Drain-induced Barrier Lowering (DIBL) and subthershold swing are determined. A nice agreement between the results obtained from the model and TCAD simulation demonstrates the validity and correctness of the model. A comparative study of the efficacy to suppress SCEs for Dual-Material (DM) and Single-Material (SM) junctionless surrounding gate MOSFET of the same dimensions has also been carried out. Result indicates that TM-JLSRG devices offer a noticeable enhancement in the efficacy to suppress SCEs by as compared to SM-JLSRG and DM-JLSRG device structures. The effect of different length ratios of three channel regions related to three different gate materials of TM-JLSRG structure on the SCEs have also been discussed. As a result, we demonstrate that TM-JLSRG device can be considered as a competitive contender to the deep-submicron mainstream MOSFETs for low-power VLSI applications.  相似文献   
4.
吕懿  张鹤鸣  胡辉勇  杨晋勇  殷树娟  周春宇 《物理学报》2015,64(6):67305-067305
电容特性模型是单轴应变硅金属氧化物半导体场效应晶体管(Si MOSFET)和电路进行瞬态分析、交流小信号分析、噪声分析等的重要基础. 本文首先建立了单轴应变Si NMOSFET 的16 个微分电容模型, 并将微分电容的仿真结果与实验结果进行了比较, 验证了所建模型的正确性. 同时对其中的关键性栅电容Cgg 与应力强度、偏置电压、沟道长度、栅极掺杂浓度等的关系进行了分析研究. 结果表明, 与体硅器件相比, 应变的引入使得单轴应变Si NMOSFET器件的栅电容增大, 随偏置电压、沟道长度、栅极掺杂浓度的变化趋势保持不变.  相似文献   
5.
随着铜互连以及low-k电介质在超大规模集成电路中地广泛使用,low-k电介质的机械完整性及其对互连可靠性变得更加重要。影响介电膜的机械完整性和互连可靠性的因素包括介电膜的工艺制程,芯片与封装材料的相互影响,以及环境温度和湿度的影响。本文研究集中于了解环境温度和湿度对塑封硅器件中介电薄膜的可靠性影响。采用快速温度和湿度实验条件,对塑封硅器件中介电薄膜受水分和温度损伤的敏感性进行了分析。运用商业有限元(FEA)分析软件,对水分在塑封材料和硅器件中的扩散过程进行了建模及仔细分析。并对硅器件周边密封圈的防水分扩散效力进行了研究。通过这一系列实验与分析,对塑封硅器件中介电薄膜的温湿效应有了完整地了解,并提出和建立了相关的物理模型和经验公式。运用这物理模型和经验公式可对在各种使用环境温度和湿度条件下,塑封硅器件中介电薄膜的可靠性进行评估及分析。  相似文献   
6.
The injection moulding of thermoplastics involves, during mould filling, flow of a hot molten polymer into a mould network, the walls of which are so cold that the polymer freezes on them. During the constant pressure drop part of the filling stage, but not during the preceding constant flow-rate part, freezing-off, that is premature blockage of the mould network by frozen polymer, is possible. A semi-quantitative analysis of such freezing-off at a gate is presented here. The length-scales and time-scales of all the relevant physical processes occurring during freezing-off are identified and a criterion is obtained which enables the occurrence of freezing-off to be predicted, at least crudely. a j constant - b jk constant - Br Brinkman number - Br 0 initial Brinkman number - Gz Graetz number - Gz 0 initial Graetz number - h c half-height of flat cavity - h g half-height of flat gate - h g * half-height of polymer melt region in flat gate - L c length of cavity - L f filled length - L g length of gate - m viscosity shear-rate exponent - P pressure drop - Q volumetric flow-rate - r radial coordinate in round gate and cavity - R c radius of round cavity - R g radius of round gate - R g * radius of polymer melt region in round gate - Sf Stefan number - t time - t f freeze-off time - T temperature - T i inlet polymer melt temperature - T m melting temperature of polymer - T w gate wall temperature - u r radial velocity in round gate - u x axial velocity in flat gate - u y transverse velocity in flat gate - u z axial velocity in round gate - w c width of flat channel - w g width of flat gate - x axial coordinate in flat gate and cavity - y transverse coordinate in flat gate and cavity - z axial coordinate in round gate and cavity - thermal conductivity of molten polymer - thermal conductivity of frozen polymer - heat capacity of molten polymer - heat capacity of frozen polymer - h ratio of half-height of flat gate to that of flat cavity - R ratio of radius of round gate to that of round cavity - w ratio of width of flat gate to that of flat cavity - dimensionless axial coordinate in round gate and cavity - dimensionless transverse coordinate in flat gate and cavity - * dimensionless half-height of polymer melt region in flat gate - dimensionless temperature - i dimensionless inlet temperature - j j-th term in power series expansion of dimensionless temperature - thermal diffusivity ratio - dimensionless filled length - latent heat of fusion of polymer - µ viscosity - µ 0 unit shear-rate viscosity - v j j-th eigenvalue - j-th zero of zeroth-order Bessel function of first kind - dimensionless axial coordinate in flat gate and cavity - c dimensionless pressure drop in cavity - g dimensionless pressure drop in gate - density of molten polymer - density of frozen polymer - dimensionless radial coordinate in round gate and cavity - * dimensionless radius of polymer melt region in round gate - dimensionless time - f dimensionless freeze-off time - 0 dimensionless time at start of final phase of freezing-off - rescaled dimensionless time - rescaled dimensionless freeze-off time - rescaled dimensionless time at start of final phase of freezing-off - dimensionless similarity variable - dummy variable - scaled dimensionless axial coordinate in gate  相似文献   
7.
通过对线间电容耦合模型的研究, 提出了一种基于互连线电容耦合的SR锁存电路设计方案. 该方案首先分析互连线间电容耦合关系, 利用MOS管栅极电容模拟互连线电容; 然后利用电容耦合结构与线计算特性, 设计或非逻辑门电路, 在此基础上实现基于互连线电容耦合的SR锁存电路; 最后在TSMC 65nm Spectre环境下仿真验证. 结果表明 所设计的电路逻辑功能正 确, 且具有低硬件开销特性.  相似文献   
8.
A low-operating voltage and high performance polymeric field effect transistors using octadecylphosphonic acid-treated high-k AlOx and HfO2 hybrid dielectrics were demonstrated. High-k metal oxide hybrid dielectrics were prepared by oxygen plasma treatment of deposited Al film for AlOx and by spin coating of solution-processable HfO2 sol-gel solution for HfO2 in combination with phosphoric acid-based self-assembled monolayer (SAM), resulting in high capacitance (10 nF/cm2 for SiO2, 600 nF/cm2 for AlOx and 580 nF/cm2 for HfO2). With phosphoric acid-based SAM on high-k metal oxide and thermal annealing of thieno[3,2-b]thiophene-based conducting polymer, the device performance was significantly enhanced. The highest mobility of the transistors using ODPA-treated AlOx as a gate dielectric is 2.3 × 10?2 cm2 V?1 s?1 in the saturation region with the source-drain of ?2 V. In ODPA-treated HfO2 hybrid dielectric, the saturated mobility is 1.1 × 10?2 cm2 V?1 s?1 and the threshold voltage was measured to be ?0.31 V, which is at least one order lower than SiO2 hybrid dielectric (?3 V).  相似文献   
9.
The highly porous and stable metal–organic framework (MOF) UiO‐66 was altered using post‐synthetic modifications (PSMs). Prefunctionalization allowed the introduction of carbon double bonds into the framework through a four‐step synthesis from 2‐bromo‐1,4‐benzenedicarboxylic acid; the organic linker 2‐allyl‐1,4‐benzenedicarboxylic acid was obtained. The corresponding functionalized MOF (UiO‐66‐allyl) served as a platform for further PSMs. From UiO‐66‐allyl, epoxy, dibromide, thioether, diamine, and amino alcohol functionalities were synthesized. The abilities of these compounds to adsorb CO2 and N2 were compared, which revealed the structure–selectivity correlations. All synthesized MOFs showed profound thermal stability together with an increased ability for selective CO2 uptake and molecular gate functionalities at low temperatures.  相似文献   
10.
高介电常数陶瓷储能脉冲形成线需要用到多开关触发的层叠Blumlein线结构。从形成线波过程理论出发,分析了多开关导通时间分散性对层叠Blumlein线及其输出波形的影响。主要包括两方面影响:其一是造成输出方波脉冲的前沿和后沿均出现阶梯形畸变;其二是使得各延迟导通的平行平板Blumlein线承受过电压,容易引起陶瓷储能介质的电击穿。在不单独考虑开关电感的理想情况下,利用PSpice电路程序模拟了开关导通时间分散性对四级层叠Blumlein线的影响,模拟结果与波过程理论分析一致。为减弱这些影响,提出了可行的解决方案。  相似文献   
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