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51.
Despite the high success rate of dental implant surgery, the failures are still being reported and investigation have been undergone to improve attachment of osteoblast on the surface of implant material. With increasing interest in non-thermal atmospheric pressure plasma jet (NTAPPJ), the effects of it on the cellular mechanisms have been previously reported. Hence in this experiment, effects of NTAPPJ on osteoblast for improved attachment and possible application in dental implant surgery were investigated.Mouse osteoblast cells of MC3T3-E1 were first directly treated with NTAPPJ with air for various durations. Also to investigate the effects by culture media, culture media were separately treated with NTAPPJ for the same durations. Cell attachments were then assessed following 4 and 24 h of cell culture using Water Soluble Tetrazolium salt (WST) assay and confirmed by automated cell counter and examining under confocal laser microscope.The results showed that there was significantly improved osteoblast attachment with relatively short duration of NTAPPJ treatment. Also results indicated that NTAPPJ possibly improved osteoblast attachment through interactions with proteins in culture media that in turn interacted with cells.Hence the application of NTAPPJ on osteoblast improves cellular attachment and would be useful tool for dental implant surgery. 相似文献
52.
Stratification is one of the main causes for vaporization of cryogens and increase of tank pressure during cryogenic storage. This leads subsequent problems such as cavitation in cryo-pumps, reduced length of storage time. Hence, it is vital to prevent stratification to improve the cost efficiency of storage systems. If stratified layers exist inside the tank, they have to be removed by suitable methods without venting the vapor. Sonication is one such method capable of keeping fluid layers mixed. In the present work, a mechanistic model for ultrasonic destratification is proposed and validated with destratification experiments done in water. Then, the same model is used to predict the destratification characteristics of cryogenic liquids such as liquid nitrogen (LN2), liquid hydrogen (LH2) and liquid ammonia (LNH3). The destratification parameters are analysed for different frequencies of ultrasound and storage pressures by considering continuous and pulsed modes of ultrasonic operation. From the results, it is determined that use of high frequency ultrasound (low-power/continuous; high-power/pulsing) or low frequency ultrasound (continuous operation with moderate power) can both be effective in removing stratification. 相似文献
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Judd-Ofelt parameters obtained from the absorption spectra of Eu3+ ions doped in PbO-PbF2 glasses are intermediate between the values for fluoride and phosphate glass matrices. Eu3+ ions are coordinated to both oxide and fluoride ions. The calculated transition probabilities (As-1) for the laser transition5Do→7F2 are 171 and 170 for 30PbO-70PbF2 and 70PbO-30PbF2 glasses respectively and are significantly lower compared to phosphate glasses. The calculated (βR cal) and experimental (βRexpt) branching ratios for this transition show good agreement. The emission spectra display high energy transitions in the
440–570 nm region, a characteristic of parent matrices with low energy phonons such as the tellurite, germanate and fluoride
glasses. The electron-phonon coupling strengths deduced from the excitation spectra of Eu3+ are 10.2 x 10−3 and 9.5 x l0−3 for 30PbO-70PbF2 and 70PbO-30PbF2 glasses respectively. The relative emission intensities of the low energy transitions to high energy transitions and the
ratios of the most intense transitions5D0→7F2/5D0→7F7 significantly vary for the two glasses providing evidence for clustering of Eu3+ ions with increase in its concentration and increasing PbO content. 相似文献
55.
Change in adhesion force between a borosilicate glass microsphere and 40 Al2O3/TaN/Ru/MoSi pairs on a silicon wafer used as a multilayer extreme ultraviolet lithography mask stack were characterized by force-distance spectroscopy after cleaning Al2O3 layers using a laser induced plasma (LIP) shock wave. The adhesion force of the Al2O3 surface decreased at a higher laser energy and a lower gap distance above a threshold gap distance without changes in surface roughness. Frictional electrostatic repulsion, triboelectricity, was identified as the cause of lower adhesion forces on Al2O3 surface due to the high velocity and pressure of the LIP shock waves. The adhesion force decreased by increasing the number of exposures of LIP shock waves to the substrate. 相似文献
56.
The dually conjugate Hopf algebrasFun p,q (R) andU p,q (R) associated with the two-parametric (p,q)-Alexander-Conway solution (R) of the Yang-Baxter equation are studied. Using the Hopf duality construction, the full Hopf structure of the quasitriangular enveloping algebraU p,q (R) is extracted. The universal ?-matrix forsFun p,q (R) is derived. While expressing an arbitrary group element of the quantum group characterized by the noncommuting parameters in a representation independent way, the ?-matrix generalizes the familiar exponential relation between a Lie group and its Lie algebra. The universal ?-matrix and the FRT matrix generators,L (±), forU p,q (R) are derived from the ?-matrix. 相似文献
57.
Joseph A.J. Harame D.L. Jagannathan B. Coolbaugh D. Ahlgren D. Magerlein J. Lanzerotti L. Feilchenfeld N. St Onge S. Dunn J. Nowak E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(9):1539-1558
We present the status and direction of silicon semiconductor technologies targeted for applications such as wireless, networking, instrumentation, and storage markets. Various technological aspects for multiple branches of RF foundry technologies that are based on the standard foundry compatible CMOS node are discussed - SiGe BiCMOS HP ("high performance") tailored to high-frequency applications, SiGe BiCMOS WL ("cost performance") tailored to wireless/storage applications, and RF-CMOS optimized for low-cost consumer applications. Future opportunities and challenges for advancement in RF technologies are described in light of CMOS and SiGe heterojunction bipolar transistor scaling. In addition, we discuss the maturity of SiGe BiCMOS by looking at the levels of integration and manufacturability. 相似文献
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59.
Jagannathan B. Meghelli M. Rylyakov A.V. Groves R.A. Chinthakindi A.K. Schnabel C.M. Ahlgren D.A. Freeman G.G. Stein K.J. Subbanna S. 《Electron Device Letters, IEEE》2002,23(9):541-543
This letter reports on the room temperature operation of a conventional SiGe bipolar ECL ring oscillator with a minimum stage delay of 4.2 ps for ~250 mV single ended voltage swing. To our knowledge, this is the lowest reported delay for a gate fabricated using transistor devices. The circuit uses 0.12 × 2 μm2 emitter size SiGe n-p-n transistors with a room temperature fT of 207 GHz and fMAX (unilateral gain extrapolation) of 285 GHz. The ring oscillator was studied as a function of various device and circuit parameters and it was found that minimum delay is more dependent on the parasitic resistance and capacitance in the n-p-n device than on pure transit time across the device 相似文献
60.
S Jagannathan ET Küsel P Ratilal NC Makris 《The Journal of the Acoustical Society of America》2012,132(2):680-693
Bistatic, long-range measurements of acoustic scattered returns from vertically extended, air-filled tubular targets were made during three distinct field experiments in fluctuating continental shelf waveguides. It is shown that Sonar Equation estimates of mean target-scattered intensity lead to large errors, differing by an order of magnitude from both the measurements and waveguide scattering theory. The use of the Ingenito scattering model is also shown to lead to significant errors in estimating mean target-scattered intensity in the field experiments because they were conducted in range-dependent ocean environments with large variations in sound speed structure over the depth of the targets, scenarios that violate basic assumptions of the Ingenito model. Green's theorem based full-field modeling that describes scattering from vertically extended tubular targets in range-dependent ocean waveguides by taking into account nonuniform sound speed structure over the target's depth extent is shown to accurately describe the statistics of the targets' scattered field in all three field experiments. Returns from the man-made targets are also shown to have a very different spectral dependence from the natural target-like clutter of the dominant fish schools observed, suggesting that judicious multi-frequency sensing may often provide a useful means of distinguishing fish from man-made targets. 相似文献