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121.
122.
Byunggeor Moon 《Papers in Regional Science》2019,98(6):2343-2354
This paper explores the stringency of floor area ratio (FAR), one of the land use regulations in New York, and analyses it by boroughs of New York. Stringency is presented when the regulated height is significantly lower than the free market height and the theoretical approach shows that the elasticity of the land value with respect to FAR is used to estimate the stringency. In particular, we overcome issues in previous studies by constructing a data set using publically available data through new methods. The results show that the FAR stringency in Manhattan is the highest in New York City and the stringency is lower as the distance from the centre of the city increases. 相似文献
123.
Freddy DeAngelis Murali Gopal Muraleedharan Jaeyun Moon Hamid Reza Seyf Austin J. Minnich Alan J. H. McGaughey 《Nanoscale and Microscale Thermophysical Engineering》2019,23(2):81-116
ABSTRACTWe review the status of research on thermal/phonon transport in disordered materials. The term disordered materials is used here to encompass both structural and compositional disorder. It includes structural deviations ranging from an ideal crystal with disordered arrangements of defects all the way to fully amorphous materials, as well as crystals with impurities up through multi-component random alloys. Both types of disorder affect phonons by breaking the symmetry of an idealized crystal and changing their character/mode shapes. These effects have important implications with regard to phonon–phonon interactions, phonon transport and phonon interactions with other quantum particles, which are being actively investigated. Herein, we synthesize the current theoretical understanding, identify the aspects of the problem that require more work, and pose open questions. Abbreviations: BTE: Boltzmann transport equation; DFT: Density functional theory; EPP: Eigenvector periodicity parameter; FAFDTR: Fiber-aligned frequency domain thermoreflectance; GK: Green–Kubo; GKMA: Green–Kubo modal analysis; HCACF: Heat current autocorrelation function; IXS: Inelastic X-ray scattering; LD: Lattice dynamics; LJ: Lennard–Jones; MD: Molecular dynamics; MFP: Mean free path; NEMD: Non-equilibrium molecular dynamics; NMD: Normal-mode dynamics; PDL: Propagon, diffuson, locon; PGM: Phonon gas model; PR: Participation ratio; SCLD: Supercell lattice dynamics; SED: Spectral energy density; TDTR: Time-domain thermoreflectance; VCA: Virtual crystal approximation; 相似文献
124.
125.
Combined Application of Antibrowning,Heat Treatment and Modified‐Atmosphere Packaging to Extend the Shelf Life of Fresh‐Cut Lotus Root 下载免费PDF全文
Jihye Son Jeong‐Eun Hyun Jo‐Won Lee Sun‐Young Lee BoKyung Moon 《Journal of food science》2015,80(6):C1178-C1187
This work aimed to determine the effects of different concentrations of antibrowning treatments (that is, distilled water [DW], 1% ascorbic acid [AA], 0.5% chamomile [CM], and 1% AA + 0.5% CM) and heat‐treatment (55 °C for 45 s) combined with packaging under 4 different modified‐atmosphere gas compositions (that is, air, vacuum, 100% CO2, 50% CO2/50% N2) on the quality and microbiological characteristics of fresh‐cut lotus root. The quality characteristics (that is, color, weight loss, texture, pH, polyphenoloxidase activity, and total phenolic content) of the AA + CM‐dipped sample in 100% CO2 packaging were maintained significantly better than those of the other samples (P < 0.05). The microbiological counts observed in the DW‐dipped sample during storage were higher than those of the AA, CM, and AA + CM samples, and heat‐treatment retarded the microbiological deterioration of fresh‐cut lotus root. Therefore, the results revealed that dipping in an antibrowning treatment (AA + CM), and 100% CO2 MAP with heat treatment effectively extend the shelf life of fresh‐cut lotus root to 21 d at 5 °C. 相似文献
126.
Park KH Lee SQ Kim EK Moon SE Cho YH Gokarna A Jin LH Kim S Cho W Lee YI 《Ultramicroscopy》2008,108(10):1319-1324
We have developed a low cost and a highly compact bio-chip detection technology by modifying a commercially available optical pick-up head for CD/DVD. The highly parallel and miniaturized hybridization assays are addressed by the fluorescence emitted by the DNA-chip using the optical pick-up head. The gap between the objective lens and the bio-chip is regulated by the focus servo during the detection of the fluorescence signal. High-resolution and high-speed scanning is effectively realized by this simple scanning system instead of utilizing high-precision mechanism. Regardless of achievement of effective detection mechanism, the technique of fluorescence detection can prove to be disadvantageous because of the low stability of the dyes with low S/N ratio and an expensive setup such as a PMT detector is always required for fluorescence detection. We propose, for the first time, a novel scanning scheme based on metal nanoparticles in combination with a bio-chip substrate having a phase change recording layer. We found that the phase change process is highly affected by the existence of the densely condensed metal nanoparticles on the phase change layer during the writing process of the pick-up head. 相似文献
127.
We studied a new lift-off process of thin Au film on silicon surfaces in nanometer-scale, combining anodic oxidation patterning with AFM, deposition of Au thin film on the patterned substrate and chemical etching processes of the Si oxide underneath the Au film. For Au films of thickness of 2-5 nm, the Au films on the Si oxide patterns were left unbroken and bent down to stick to Si surface after the removal of the oxide by the chemical etching. For an Au film of 1 nm in thickness, it was possible to lift-off the Au film on oxide patterns of the lines and dots in nanometer-scale using Si oxide as a sacrificial mask. 相似文献
128.
Development of the active balancing device for high-speed spindle system using influence coefficients 总被引:10,自引:0,他引:10
Jong-Duk Moon Bong-Suk Kim Soo-Hun Lee 《International Journal of Machine Tools and Manufacture》2006,46(9):978-987
A high-speed spindle can be very sensitive to rotating mass unbalance which has harmful effect on many types of rotating machinery. Therefore, the balancing procedure is certainly needed to reduce vibration in all high-speed rotating systems. In this study, an active balancing program using influence coefficient method and an active balancing device of an electro-magnetic type with both simple and reliable structures were applied to the developed high-speed spindle system. A gain scheduling control using influence coefficients of the reference model was proved to be effective in balancing the spindle system although its characteristics were changed. The stability of reference influence coefficients was verified by experiments with frequency response functions. The active balancing experiment of the manufactured spindle system using an active balancing program and device was also performed efficiently during the operation. As a result, controlled unbalance responses after balancing work were below the vibration limit at all rotating speed ranges including critical speeds. 相似文献
129.
A 5 wt% CoOx/TiO2 catalyst has been used to study the effect of calcination temperature on the activity of this catalyst for CO oxidation at 100 °C under a net oxidizing condition in a continuous flow type fixed-bed reactor system, and the catalyst samples have been characterized using TPD, XPS and XRD measurements. The catalyst after calcination at 450 °C gave highest activity for this low-temperature CO oxidation, and XPS measurements yielded that a 780.2-eV Co 2p3/2 main peak appeared with this catalyst sample and this binding energy was similar to that measured with pure Co3O4. After calcination at 570 °C, the catalyst, which had possessed practically no activity in the oxidation reaction, gave a Co 2p3/2 main structure peak at 781.3 eV which was very similar to those obtained for synthesized ConTiOn+2 compounds (CoTiO3 and Co2TiO4), and this catalyst sample had relatively negligible CO chemisorption as observed by TPD spectra. XRD peaks indicating only the formation of Co3O4 particles on titania surface were developed in the catalyst samples after calcination at temperatures ≥350 °C. Based on these characterization results, five types of Co species could be modeled to exist with the catalyst calcined at different temperatures. Among these surface Co species, the Type A clean Co3O4 particles were predominant on a sample of the catalyst after calcination at 450 °C and highly active for CO oxidation at 100 °C, and the calcination at 570 °C gave the Type B Co3O4 particles with complete ConTiOn+2 overlayers inactive for this oxidation reaction. 相似文献
130.
Electrochemical cell current requirements for toxic organic waste destruction in Ce(IV)-mediated electrochemical oxidation process 总被引:1,自引:0,他引:1
Vasily V. Kokovkin Sang Joon Chung Subramanian Balaji Manickam Matheswaran Il-Shik Moon 《Korean Journal of Chemical Engineering》2007,24(5):749-756
The electrochemical cell for cerium oxidation and reactor for organic destruction are the most important operation units for
the successful working mediated electrochemical oxidation (MEO) process. In this study, electrochemical cells with DSA electrodes
of two types, single stack and double stack connected in series, were used. The performances towards the electrochemical generation
of Ce(IV) in nitric acid media at 80 °C were studied. The current-voltage curves and cerium electrolysis kinetics showed the
dependence on number of cell stacks needed to be connected in series for the destruction of a given quantity of organic pollutant.
The presence of an optimum region for Ce(III) oxidation with a contribution of oxygen evolution, especially at low Ce(III)
concentration (high conversion ratios), was found. The cells were applied for the Ce(IV) regeneration during the organic destruction.
The cell and reactor processes were fitted in a simple model proposed and used to calculate the current needed in terms of
Ce(III) oxidation rate and the number of cell stacks required for maintaining Ce(IV)/Ce(III) ratio at the same level during
the organic destruction. This consideration was based on the kinetic model previously developed by us for the organic destruction
in the MEO process. 相似文献