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961.
Chu L. H. Chang E. Y. Chang L. Wu Y. H. Chen S. H. Hsu H. T. Lee T. L. Lien Y. C. Chang C. Y. 《Electron Device Letters, IEEE》2007,28(2):82-85
An enhancement-mode InGaP/AlGaAs/InGaAs pseudomorphic high-electron mobility transistor using platinum (Pt) as the Schottky contact metal was investigated for the first time. Following the Pt/Ti/Pt/Au gate metal deposition, the devices were thermally annealed at 325 degC for gate sinking. After the annealing, the device showed a positive threshold voltage (Vth) shift from 0.17 to 0.41 V and a very low drain leakage current from 1.56 to 0.16 muA/mm. These improvements are attributed to the Schottky barrier height increase and the decrease of the gate-to-channel distance as Pt sinks into the InGaP Schottky layer during gate-sinking process. The shift in the Vth was very uniform across a 4-in wafer and was reproducible from wafer to wafer. The device also showed excellent RF power performance after the gate-sinking process 相似文献
962.
Two-stage stepped-impedance resonator (SIR) filters are designed to have a wide upper stopband. Two transmission zeros are also created near the passband to form a quasi-elliptic response. For a 20-dB rejection level, with properly designed SIR geometry and tapped-line structure, the leading three spurious resonances of the SIR are suppressed by transmission zeros and respective unmatched singly loaded Q (Qsi) values. Measured results illustrate that stopbands up to 8.4 and 5.3 times the design frequency can be achieved for rejection levels of 20 and 30dB, respectively 相似文献
963.
Wu Y. C. Chang E. Y. Lin Y. C. Hsu H. T. Chen S. H. Wu W. C. Chu L. H. Chang C. Y. 《Microwave and Wireless Components Letters, IEEE》2007,17(2):133-135
Copper metallized AlGaAs/InGaAs pseudomorphic high-electron-mobility transistor (PHEMT) single-pole-double-throw (SPDT) switches utilizing platinum (Pt, 70nm) as the diffusion barrier is reported for the first time. In comparison with the Au metallized switches, the Cu metallized SPDT switches exhibited comparable performance with insertion loss of less than 0.5dB, isolation larger than 35dB and the input power for one dB compression (input P1dB ) of 27dBm at 2.5GHz. These switches were annealed at 250deg for 20h for thermal stability test and showed no degradation of the dc characteristics after the annealing. Also, after 144h of high temperature storage life (HTSL) environment test, these switches still remained excellent and reliable radio frequency (RF) characteristics. It is successfully demonstrated for the first time that the copper metallization using Pt as the diffusion barrier could be applied to the GaAs monolithic microwave integrated circuits switch fabrication with good RF performance and reliability 相似文献
964.
A 15-60 GHz asymmetric broadside coupled balun fabricated in the standard TSMC 0.18 mum CMOS process is demonstrated. Using the broadside tight coupling technique, the balun is achieved with wide bandwidth and low insertion loss and utilises the inherent three-dimensional multilayer structure in CMOS technology. The balun achieves bandwidth of over 120%, the minimum insertion loss is better than 1.1 dB, amplitude difference is less than 1 dB and phase difference is less than 5deg (15-60 GHz). The occupied chip area is only 0.06 mm2. 相似文献
965.
Hong-Yu Lin Hsu S.S.H. Chih-Yuan Chan Jun-De Jin Yu-Syuan Lin 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2007,54(9):750-754
A fully integrated frequency divider with an operation frequency up to 20 GHz is designed in 0.18-mum CMOS technology. The frequency divider includes two stages to divide the input signal by a factor of 4. A wide locking range from 18.8 to 23.2 GHz was obtained with a low phase noise of -134.8 dBc/Hz (1-MHz offset) at an output frequency of 4.7 GHz. The first stage is designed by an analog methodology with the varactors to extend the locking range, while the second stage is designed by a digital approach with the RF devices for a high operation frequency. With the advantages of both designs, this frequency divider is operated at the frequency range suitable for LMDS applications. 相似文献
966.
A new type of CPW-fed dual-annular-slot antenna operated in the 5.8 GHz band is introduced. Both the inductive and the capacitive configurations are presented. The design considerations of the antennas are discussed. Measurement shows that the antennas have a wide bandwidth of 16% with a peak gain of 5.4 dBi for the inductive configuration and 7.8% with a peak gain of 4 dBi for the capacitive configuration. 相似文献
967.
Bard K. Dewey B. Hsu M.-T. Mitchell T. Moody K. Rao V. Rose R. Soreff J. Washburn S. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2007,95(3):530-554
IBM's high-performance microprocessor designs leverage internally developed electronic design automation tools to create high-frequency, power efficient, and robust microprocessors. This paper describes some of the tools employed in the custom circuit design methodology in IBM. The tools described include a transistor-level block-based static timer, a static noise analysis methodology, and a transistor width tuner that optimizes performance and area. We also describe the application of electrical rule checking used to enforce consistent design practices. Finally, we discuss a macro extraction tool that determines parasitic resistance and capacitance of interconnect from a layout 相似文献
968.
Chain-Shu Hsu Hwai-Len Chen 《Journal of polymer science. Part A, Polymer chemistry》1999,37(21):3929-3935
The photoinitiated polymerization of 2-chloro-1,4-phenylene bis[4-[6-(acryloyloxy)hexyloxy]benzoate] (1M) was studied. The monomer 1M exhibited a broad nematic phase between 24.9 and 113.7 °C on a DSC cooling scan. It was oriented in its nematic phase at a substrate coated with polyimide and unidirectionally rubbed with a nylon cloth. During polymerization, the ordering of the liquid–crystal molecules was fixed, yielding a uniaxially crosslinked network. The clear liquid–crystal networks (LCNs) exhibited a birefringence between 0.14 and 0.19, depending on the polymerization temperature. Finally, a nonmesogenic diluent, tetra(ethylene glycol)diacrylate, was mixed with 1M, subsequently decreasing the birefringence of the obtained LCNs. The LCNs containing nonmesogenic diluent exhibited not only a smaller birefringence but also a weaker birefringence dispersion in the visible region. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3929–3935, 1999 相似文献
969.
Chui-Wei Wong Ling-Ning Ko Hung-Jin Huang Chii-Shen Yang Shan-hui Hsu 《Molecules (Basel, Switzerland)》2021,26(23)
Highly expressible bacteriorhodopsin (HEBR) is a light-triggered protein (optogenetic protein) that has seven transmembrane regions with retinal bound as their chromophore to sense light. HEBR has controllable photochemical properties and regulates activity on proton pumping. In this study, we generated HEBR protein and incubated with lung cancer cell lines (A549 and H1299) to evaluate if there was a growth-inhibitory effect with or without light illumination. The data revealed that the HEBR protein suppressed cell proliferation and induced the G0/G1 cell cycle arrest without light illumination. Moreover, the migration abilities of A549 and H1299 cells were reduced by ~17% and ~31% after incubation with HEBR (40 μg/mL) for 4 h. The Snail-1 gene expression level of the A549 cells was significantly downregulated by ~50% after the treatment of HEBR. In addition, HEBR significantly inhibited the gene expression of Sox-2 and Oct-4 in H1299 cells. These results suggested that the HEBR protein may inhibit cell proliferation and cell cycle progression of lung cancer cells, reduce their migration activity, and suppress some stemness-related genes. These findings also suggested the potential of HEBR protein to regulate the growth and migration of tumor cells, which may offer the possibility for an anticancer drug. 相似文献
970.
Kuo-Shun Liao Meng-Jung Tsai Li-Jen Hsu Chih-Min Wang Jing-Yun Wu 《Molecules (Basel, Switzerland)》2021,26(23)
Hydro(solvo)thermal reactions of Cd(NO3)2, N-(pyridin-3-ylmethyl)-4-(pyridin-4-yl)-1,8-naphthalimide (NI-mbpy-34), and 5-bromobenzene-1,3-dicarboxylic acid (Br-1,3-H2bdc) afforded a luminescent coordination polymer, {[Cd(Br-1,3-bdc)(NI-mbpy-34)(H2O)]∙2H2O}n (1). Single-crystal X-ray diffraction analysis showed that 1 features a two-dimensional (2-D) gridlike sql layer with the point symbol of (44·62), where the Cd(II) center adopts a {CdO5N2} pentagonal bipyramidal geometry. Thermogravimetric (TG) analysis confirmed the thermal stability of 1 up to about 340 °C, whereas XRPD patterns proved the maintenance of crystallinity and framework integrity of 1 in CH2Cl2, H2O, CH3OH, and toluene. Photoluminescence studies indicated that 1 displayed intense blue fluorescence emissions in both solid-state and H2O suspension-phase. Owing to the good fluorescent properties, 1 could serve as an excellent turn-off fluorescence sensor for selective and sensitive Cr(VI) detection in water, with LOD = 15.15 μM for CrO42− and 14.91 μM for Cr2O72−, through energy competition absorption mechanism. In addition, 1 could also sensitively detect Cr3+, Fe3+, and Al3+ ions in aqueous medium via fluorescence-enhancement responses, with LOD = 2.81 μM for Cr3+, 3.82 μM for Fe3+, and 3.37 μM for Al3+, mainly through an absorbance-caused enhancement (ACE) mechanism. 相似文献