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101.
Recent reports have identified a three-wave optically parametric mechanism for the active enhancement of fluorescence using off-resonant radiation. In this Letter it is shown by numerical simulation that the output of a laser system optically pumped just below threshold, can be strongly enhanced by this mechanism, using an ancillary beam of moderate intensity. The electrodynamics and kinetics of the nonlinear optical mechanism are analyzed, model calculations performed, and the output is illustrated graphically. The response demonstrates a novel method for achieving all-optical transistor action. 相似文献
102.
Herein we present a textile wearable electrochemical transistor by functionalizing a single cotton yarn with semiconducting polymer. The organic electrochemical transistor (OECT), which is low cost and completely integrated e-textile, is decorated by adsorption of the fungal laccase POXA1b, and is used as biosensor for the direct detection of Tyrosine (L-Tyr) without the use of electron mediators. The detection of Tyr in real-case scenario such as human physiological fluids would own a paramount importance in noninvasive analysis of the patient's condition, monitoring and preventing several pathologies. To assess the reaction progression, the redox process is studied by UV–visible absorption with test reference molecule of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS): the results confirmed that the oxidation reaction is driven by the presence of laccase enzyme and direct electron transfer occurred. The modulation of the signal response and the kinetic of the signal is used to detect Tyr molecule in aqueous solution and the role of the enzyme adsorption on the textile is analyzed. A kinetic analysis of the characteristic modulation times of the sensing curves, confirm the sensing properties of the textile device. The textile-based biosensor is demonstrated to monitor human health biomarkers through wearable applications in a non-invasive way, finding potential application in sport, healthcare and working safety. 相似文献
103.
Sung Jin Park Sul Ong Kim Sung Ouk Jung Mi-Hye Yi Yun-Hi Kim Soon-Ki Kwon 《Journal of Electronic Materials》2009,38(9):2000-2005
An organic field-effect transistor was fabricated based on a thin film of 1,4-bis-(2-naphthalen-2-ylvinyl)benzene (BNDV).
The organic semiconductor was deposited via thermal evaporation on a chemically modified silicon dioxide surface. The thermal,
optical, electronic, and surface properties of the BNDV compound were investigated by thermogravimetric analysis, differential
scanning calorimetry, ultraviolet–visible (UV–vis) absorption, photoluminescence spectroscopies, cyclic voltammetry, x-ray
diffraction, and atomic force microscopy. The BNDV had good oxidation stability and exhibited a field-effect performance with
a mobility of 0.062 cm2/V s, a subthreshold slope of 0.4 V, and an on/off ratio of 2.45 × 105. 相似文献
104.
Regular conjugated terpolymers comprising two different acceptors and bithiophene donor in repeating group: Effect of strong and weak acceptors on semiconducting properties 下载免费PDF全文
Duc Nghia Nguyen Trinh Tung Ngo Dae Hee Lee Min Ju Cho Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2016,54(10):1339-1347
Diketopyrrolopyrrole (DPP)‐based terpolymers—P(DPP‐TPyT) and P(DPP‐T3MTT)—bearing bithiophene donating groups and weak accepting units such as pyridine (Py) or methyl thiophene‐3‐carboxylate (3MT), in the polymer backbone, were successfully synthesized. Although the two polymers had similar physical and electrochemical properties, grazing incidence X‐ray diffraction patterns of P(DPP‐TPyT) and P(DPP‐T3MTT) showed mixed and edge‐on orientations, respectively, in thermally annealed films. Accordingly, the P(DPP‐T3MTT) showed twice the hole mobility of P(DPP‐TPyT) in a thin‐film transistor, and a blended film of P(DPP‐T3MTT) and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) showed better power conversion efficiency in a polymer solar cell. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1339‐1347 相似文献
105.
Seokgeun Jin Byung Jun Jung Chung Kun Song Jeonghun Kwak 《Current Applied Physics》2014,14(12):1809-1812
We introduce a room temperature and solution-processible vanadium oxide (VOx) buffer layer beneath Au source/drain electrodes for bottom-contact (BC) organic field-effect transistors (OFETs). The OFETs with the VOx buffer layer exhibited higher mobility and lower threshold voltages than the devices without a buffer layer. The hole mobility with VOx was over 0.11 cm2/V with the BC geometry with a short channel length (10 μm), even without a surface treatment on SiO2. The channel width normalized contact resistance was decreased from 98 kΩ cm to 23 kΩ cm with VOx. The improved mobility and the reduced contact resistance were attributed to the enhanced continuity of pentacene grains, and the increased work function and adhesion of the Au electrodes using the VOx buffer layer. 相似文献
106.
A nonvolatile organic field-effect transistor (OFET) with a polymeric electret as gate insulator and spun cast film of lead phthalocyanine (PbPc) as semiconductor channel is reported. Hysteresis induced by gate–bias stress was exploited to study nonvolatile memory effects. The observation of the hysteresis and memory window is proposed to originate from charge storage in the polymeric electret. The on state retention time for the OFET memory device is more than 5 h and the device can reproduce continuous write–read–erase–read switching cycles. 相似文献
107.
A. Coppa V. Foglietti E. Giovine A. Doria G.P. Gallerano E. Giovenale A. Cetronio C. Lanzieri M. Peroni F. Evangelisti 《Infrared Physics & Technology》2008,51(5):470-472
An active two dimensional near field imaging of a High Electron Mobility Transistor (HEMT) used as THz detector has been performed. The reflective imaging system developed at the ENEA FEL Facility in Frascati has been used to this purpose. This imaging technique has shown to be particularly powerful in resolving various coupling mechanisms of the incident radiation with the device. 相似文献
108.
Characteristics of pentacene organic thin film transistor with top gate and bottom contact 下载免费PDF全文
High performance pentacene organic thin film transistors (OTFT) were
designed and fabricated using SiO2 deposited by electron beam
evaporation as gate dielectric material. Pentacene thin films were
prepared on glass substrate with S--D electrode pattern made from ITO
by means of thermal evaporation through self-organized process. The
threshold voltage VTH was --2.75± 0.1V in 0---50V
range, and that subthreshold slopes were 0.42± 0.05V/dec. The
field-effect mobility (μEF) of OTFT device increased with
the increase of VDS, but the μEF of OTFT device
increased and then decreased with increased VGS when VDS was kept constant. When VDS was --50V, on/off current
ratio was 0.48× 105 and subthreshold slope was 0.44V/dec.
The μEF was 1.10cm2/(V.s), threshold voltage
was --2.71V for the OTFT device. 相似文献
109.
For a surface-channel n-MOSFET and a buried-channel p-MOSFET, the effect of plasma process-induced damage on bias temperature instability (BTI) was investigated. The gate oxide thickness, tox, of the test MOSFETs was 2.0, 3.0, or 4.5 nm. The shifts of threshold voltage Vth and of linear drain current Idlin were measured after applying a BTI stress at a temperature of 125 °C. The measured shifts of Vth and Idlin indicate that BTI on ultra-thin gate CMOS devices appears only in the form of SiO2/Si interface degradation, and that the positive BTI for the n-MOSFET as well as the negative BTI for the p-MOSFET is important for the reliability evaluation of CMOS devices. Because of positive plasma charging to the gate, a protection diode was very efficient at reducing BTI for the p-MOSFET, but it was much less effective for the n-MOSFET. 相似文献
110.
Theodore Chung Jae Limb Jae-Hyun Ryou Wonseok Lee Peng Li Dongwon Yoo Xue-Bing Zhang Shyh-Chiang Shen Russell D. Dupuis David Keogh Peter Asbeck Ben Chukung Milton Feng Dimitri Zakharov Zusanne Lilienthal-Weber 《Journal of Electronic Materials》2006,35(4):695-700
The design and growth of GaN/InGaN heterojunction bipolar transistors (HBTs) by metalorganic chemical vapor deposition (MOCVD)
are studied. Atomic-force microscopy (AFM) images of p+InGaN base layers (∼100 nm) deposited under various growth conditions indicate that the optimal growth temperature is limited
to the range between 810 and 830°C due to a trade-off between surface roughness and indium incorporation. At these temperatures,
the growth pressure must be kept above 300 Torr in order to keep surface pit density under control. An InGaN graded-composition
emitter is adopted in order to reduce the number of V-shaped defects, which appear at the interface between GaN emitter and
InGaN base and render an abrupt emitter-base heterojunction nearly impossible. However, the device performance is severely
limited by the high p-type base contact resistance due to surface etching damage, which resulted from the emitter mesa etch. 相似文献