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451.
Wireless Personal Communications - In general, topology design is the most important framework in network communication. In this research, a star topology is adapted as an application. Normally,... 相似文献
452.
Prabhakaran Selvaraj Anurag Roy Habib Ullah Parukuttyamma Sujatha Devi Asif Ali Tahir Tapas Kumar Mallick Senthilarasu Sundaram 《国际能源研究杂志》2019,43(1):523-534
In the present work, 10 to 14 nm titania nanoparticles with high‐packing density are synthesized by the soft‐template method using a range of cationic surfactants including cetyl trimethylammonium bromide (CTAB), Sodium dodecyl sulfate (SDS), and dodecyl trimethylammonium bromide (DTAB). The synthesized nanoparticles are used as a photoanode material in dye solar cells. Density functional theory (DFT) simulations reproduce our experimental results of charge transfer and strong interaction between the TiO2 and N719. N719‐TiO2 complex establishes strong electrostatic bonding through H of the dye with the O of TiO2 surface. Solar cell efficiency of 6.08% with 12.63 mA/cm2, 793 mV, and 48.5% for short circuit current density, open circuit voltage, and fill factor, respectively, are obtained under 1 sun illumination for the dye‐sensitized solar cell (DSSC) using a film of mesoporous TiO2 synthesized from the SDS surfactant. On the other hand, the 21 nm commercial TiO2 powder (P25) device results in 4.60% efficiency under similar conditions. Electrochemical impedance spectroscopic studies show that the SDS device has lesser charge transport resistance than the other devices because of its higher surface area, packing density, and dye loading capacity. Our results show that employing high packing density‐based TiO2 nanoparticles represents a commercially viable approach for highly beneficial photoanode development for future DSSC applications. 相似文献
453.
Chandran Kalyana Sundaram Perumalsamy Marichamy 《Wireless Personal Communications》2018,102(4):3041-3053
Wireless Personal Communications - As the surging demands of secure power supply and reliable power system, the power load approximation and forecasting are becoming more significant and more... 相似文献
454.
Ali Sadeghian Laksshman Sundaram Daisy Zhe Wang William F. Hamilton Karl Branting Craig Pfeifer 《Artificial Intelligence and Law》2018,26(2):127-144
A large number of cross-references to various bodies of text are used in legal texts, each serving a different purpose. It is often necessary for authorities and companies to look into certain types of these citations. Yet, there is a lack of automatic tools to aid in this process. Recently, citation graphs have been used to improve the intelligibility of complex rule frameworks. We propose an algorithm that builds the citation graph from a document and automatically labels each edge according to its purpose. Our method uses the citing text only and thus works only on citations who’s purpose can be uniquely identified by their surrounding text. This framework is then applied to the US code. This paper includes defining and evaluating a standard gold set of labels that cover a vast majority of citation types which appear in the “US Code” but are still short enough for practical use. We also proposed a novel linear-chain conditional random field model that extracts the features required for labeling the citations from the surrounding text. We then analyzed the effectiveness of different clustering methods such as K-means and support vector machine to automatically label each citation with the corresponding label. Besides this, we talk about the practical difficulties of this task and give a comparison of human accuracy compared to our end-to-end algorithm. 相似文献
455.
T. Lundström P. O. Holtz Q. X. Zhao J. P. Bergman B. Monemar M. Sundaram J. L. Merz A. C. Gossard 《Journal of Electronic Materials》1993,22(11):1353-1359
The radiative recombination processes involving two dimensional (2D) carriers from the notch potential formed at the interface
of modulation doped GaAs/AlGaAs heterostructures have been studied by means of photoluminescence (PL) and photoluminescence
excitation spectroscopy in the presence of an external electric field applied perpendicular to the layers via a gate electrode.
Two PL bands related to the 2D electron gas are interpreted as the radiative recombination between 2D electrons and holes
from the valence band (HB1) and from residual acceptors (HB2), respectively. The band bending in the active layer, which determines
the energy positions of these H-bands, can be controlled by applying an external electric field. However, also the separation
between the Fermi edge, EF, and the second 2D electron subband is deliberately varied by applying an electric field. At a sufficiently small separation,
an efficient scattering path near k=0 is available for electrons at the Fermi energy. This can be observed in the PL spectra
as a striking enhancement of the many-body excitonic transition, usually referred to as the Fermi edge singularity (FES).
The enhancement of the FES is usually explained in terms of an efficient scattering for electrons at the Fermi edge via the
nearly resonant adjacent subband. The efficiency of this process is dependent on the separation between the Fermi edge, EF, and the next subband, which can be controlled via the applied field in our experiments. 相似文献
456.
ABSTRACT: Menhaden oil-in-water emulsions (20%, v/v) were stabilized by 2 wt% whey protein isolate (WPI) with 0.2 wt% xanthan gum (XG) in the presence of 10 mM CaCl2 and 200 μM EDTA at pH 7. Droplet size, lipid oxidation, and rheological properties of the emulsions were investigated as a function of heating temperature and time. During heating, droplet size reached a maximum at 70 °C and then decreased at 90 °C, which can be attributed to both heating effect on increased hydrophobic attractions and the influence of CaCl2 on decreased electrostatic repulsions. Combination of effects of EDTA and heat treatment contributed to oxidative stability of the heated emulsions. The rheological data indicate that the WPI/XG-stabilized emulsions undergo a state transition from being viscous like to an elastic like upon substantial thermal treatment. Heating below 70 °C or for less than 10 min at 70 °C favors droplet aggregation while heating at 90 °C or for 15 min or longer at 70 °C facilitates WPI adsorption and rearrangement. WPI adsorption leads to the formation of protein network around the droplet surface, which promotes oxidative stability of menhaden oil. Heating also aggravates thermodynamic incompatibility between XG and WPI, which contributes to droplet aggregation and the accumulation of more WPI around the droplet surfaces as well. 相似文献
457.
Vijayan C Soundararajan N Chandramohan R Dhanasekaran V Sundaram K Neyvasagam K Mahalingam T 《Journal of microscopy》2011,243(3):267-272
Semiconducting silver selenide telluride (Ag2SeTe) thin films were prepared with different thicknesses onto glass substrates at room temperature using thermal evaporation technique. The structural properties were determined as a function of thickness by X‐ray diffraction exhibiting no preferential orientation along any plane; however, the films are found to have peaks corresponding to mixed phase. The morphology of these films was studied using scanning electron microscope and atomic force microscopy respectively, and is reported. The morphological properties are found to be very sensitive to the thin film thickness. The composition of the films is also estimated using energy dispersive analysis using X‐rays and are also reported. 相似文献
458.
Oleg S. Alexeev Sundaram Krishnamoorthy Cody Jensen Michael S. Ziebarth George Yaluris Terry G. Roberie Michael D. Amiridis 《Catalysis Today》2007,127(1-4):189-198
The adsorption of CO and its reaction with NO in the 400–600 °C temperature range on Cen+/Na+/γ-Al2O3 and Pdn+/Cen+/Na+/γ-Al2O3 type materials used commercially as FCC additives were monitored by FTIR spectroscopy. Exposure of both types of samples to CO leads to the formation of carboxylates and carbonates. The concentration of these species was higher in samples containing Pd, indicating that palladium catalyzes their formation. The Pdn+ cations initially present in these samples undergo partial reduction to form metallic Pd in the presence of CO even at room temperature. More complete reduction of Pd, along with some aggregation, was observed after exposure to CO at elevated temperatures. Exposure of both types of samples to NO/CO mixtures in the 400–600 °C temperature range leads to the formation of surface isocyanate species. Both Na+ and Cen+ promote the formation of such NCO species. However, surface isocyanate species were formed with substantially higher rates in the presence of palladium. The formation of the isocyanate species strongly correlates with changes observed in the νOH region, indicating that hydroxyls actively participate in the surface chemistry involved and are capable of protonating the NCO species. The isocyanates are also reactive towards O2 and NO yielding CO2 and N2. These results suggest that isocyanates are possibly involved as intermediates in the CO–NO reaction over the materials examined. 相似文献
459.
The effects of moisture content, xanthan gum (XG) addition and glucose syrup (GS):sucrose ratio on elastic (G′) and viscous (G″) moduli during in situ gelation and on large deformation rheological properties of cured gels were investigated. An increase in both moduli of the samples with XG addition indicates network structure being strengthened. All gel samples exhibited distinct fracture. An increase in GS:sucrose ratio led to a decrease in fracture stress and an increase in fracture strain, implying more flexible polymer network. Decreasing moisture content may lead to phase separation between sugar-rich and polymer-rich phases to form stronger connection within the network structure. Textural characteristics of samples analyzed using a texture map, indicated that increasing GS:sucrose ratio rendered the sample texture more rubbery when the samples contained XG. We also related factors affecting the gelling mechanisms in terms of Tg measured by different techniques including DMA and modulated DSC. 相似文献
460.
Equation of motion of an incompressible metal plate, accelerated by a plane detonation wave, has been solved for a general value of adiabatic exponent ß of detonation products to investigate its effect on terminal velocity of the plate. It has been found that the plate velocity increases with decreasing value of ß. The magnitude of this effect has been found sufficient to determine adiabatic exponent of detonation products from the measurement of flyer plate velocities at different C/M ratios. Velocities of metal plates, hurled by contact explosion of high density explosives, have also been measured with oscillographic technique by using an experimental setup which is insensitive to air shocks. The plate velocities measured by such an experimental setup have been found in good agreement with theoretical ones. 相似文献