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101.
A High Speed, Low Voltage CMOS Offset Comparator 总被引:3,自引:0,他引:3
A high speed, low voltage offset comparator is presented. No common mode tracking circuit is used and the offset is added without compromising the high input impedance nature of the circuit. The circuit operates at 480 Mbps with 3.0–3.6 V and 1.6–2.0 V supplies and –40 to 125°C temperature range on a typical 0.5 m technology. 相似文献
102.
The leaves of Morinda citrifolia, Linn. afforded a new benzofuran and a bis-nor-isoprenoid, blumenol C, hitherto unreported from this source. The structures of these have been elucidated as 5-benzofuran carboxylic acid-6-formyl methyl ester (1) and 4-(3'(R)-hydroxybutyl)-3,5,5, trimethyl-cyclohex-2-en-1-one (2) respectively through spectroscopic studies. The NMR data (including 1D, 2D techniques) and stereochemistry at C-3' of Compound 2 is also being reported for the first time. 相似文献
103.
The statistical design of the four-MOSFET structure is presented in this paper. The quantitative measure of the effect of mismatch between the four transistors on nonlinearity and offset current is provided through contours. Statistical optimization of the transistor
and
values is demonstrated. The four-MOSFET structure was fabricated through the MOSIS 2 m process using MOS transistor Level-3 model parameters. Experimental results are included in the paper. 相似文献
104.
Chunlei Shi Yue Wu Chi-Hung Lin Mohammed Ismail 《Analog Integrated Circuits and Signal Processing》2001,26(3):221-230
This paper presents a 7-bit 64 MS/s pipeline A/D convertersuitable for wideband CDMA applications. Targeting atachieving low power dissipation at high speed, techniques suchas digital correction and optimal scaling of capacitor valuehave been employed. Switched-Opamp technique is used tofurther reduce power consumption. This ADC is implemented in0.5 m standard CMOS process. It operates from a single 3 V supply, and dissipates only 31 mW at 64 MS/s. 相似文献
105.
Murat Ali Bayir Ismail H. Toroslu Ahmet Cosar 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2007,37(1):147-153
Producing answers to a set of queries with common tasks efficiently is known as the multiple-query optimization (MQO) problem. Each query can have several alternative evaluation plans, each with a different set of tasks. Therefore, the goal of MQO is to choose the right set of plans for queries which minimizes the total execution time by performing common tasks only once. Since MQO is an NP-hard problem, several, mostly heuristics based, solutions have been proposed for solving it. To the best of our knowledge, this correspondence is the first attempt to solve MQO using an evolutionary technique, genetic algorithms 相似文献
106.
Wenfei Hu Dickie R. Cahill R. Gamble H. Ismail Y. Fusco V. Linton D. Grant N. Rea S. 《Microwave and Wireless Components Letters, IEEE》2007,17(9):667-669
A frequency selective surface (FSS) which exploits the dielectric anisotropy of liquid crystals to generate an electronically tunable bandpass filter response at D Band (110-170 GHz) is presented. The device consists of two printed arrays of slot elements which are separated by a 130-mum thick layer of liquid crystals. A 3% shift in the filter passband occurs when the substrate permittivity is increased by applying a control signal of 10 V. Measured results show that the insertion loss increases from -3.7 dB to -10.4 dB at resonance (134 GHz), thus demonstrating the potential to create a FSS which can be switched between a transmitting and a reflecting structure. 相似文献
107.
Abstract FT-IR spectroscopy has been employed in the detection of the carbonyl absorption band centered at 1728 cm?1 and assigned to the open form of D-fructose in deuterium oxide or water. Changes in the intensity of the band at 1728 cm?1 allowed the monitoring of the concentration of the open form of the keto sugar D-fructose at different temperatures and pHs. The concentration of the open form was observed to increase with increasing temperature and was an order of magnitude higher at 80 °C compared to 30 °C. The buildup of the open form was found to be extremely rapid. The new equilibrium can be reversed with decreasing temperature with a slight hysteresis. This work demonstrates the potential of applying FT-IR spectroscopy in studying the effect of environmental factors on the level of the open chain form of sugars. 相似文献
108.
The rapid scaling of integrated circuit requires further shrinkage of lateral device dimension, which correlates with pillar thickness in vertical structure. This paper investigates the effect of pillar thickness variation on vertical double gate MOSFET (VDGM) fabricated using oblique rotating ion implantation (ORI) method. For this purpose, several scenarios of silicon pillar thickness tsi were evaluated for 20–100 nm channel length. The source region was found to merge at pillar thickness below 75 nm, which results in floating body effect and creates isolated region in the middle of pillar. The vertical devices using ORI method show better performance than those with conventional implantation method for all pillar thickness, due to the elimination of corner effect that degrades the gate control. The presence of isolated depletion region in the middle of pillar at floating body increases parasitic effect for higher drain potential. By further reduction of pillar thickness towards fully depleted feature, the increase in gate-to gate charge coupling improves the performance of ORI-based vertical double gate MOSFET, as evident in near-ideal swing value and lower DIBL, compared to the partially depleted and body-tied device. 相似文献
109.
A MODFET with two 30-nm-long gates (separated by 40 nm) has been fabricated using ultrahigh-resolution electron-beam lithography. The proximity of the two gate fingers along with the ability to independently bias them results in the following features: (a) tunability of the threshold voltage, (b) enhancement of the transconductance, especially at low current levels, (c) reduction in short-channel effects, and (d) high-voltage gain and cutoff frequency 相似文献
110.
Hosein Mohamadi Abdul Samad Ismail Shaharuddin Salleh Ali Nodehi 《Wireless Personal Communications》2013,73(3):1309-1330
Recently, directional sensor networks have received a great deal of attention due to their wide range of applications in different fields. A unique characteristic of directional sensors is their limitation in both sensing angle and battery power, which highlights the significance of covering all the targets and, at the same time, extending the network lifetime. It is known as the target coverage problem that has been proved as an NP-complete problem. In this paper, we propose four learning automata-based algorithms to solve this problem. Additionally, several pruning rules are designed to improve the performance of these algorithms. To evaluate the performance of the proposed algorithms, several experiments were carried out. The theoretical maximum was used as a baseline to which the results of all the proposed algorithms are compared. The obtained results showed that the proposed algorithms could solve efficiently the target coverage problem. 相似文献