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41.
Neural Computing and Applications - Recently multimodal neuroimaging which combines signals from different brain modalities has started to be considered as a potential to improve the accuracy of...  相似文献   
42.
Monitoring and control of dangerous substances discharged into receiving waters have attracted more attention lately. Since it is not possible to analyze every single substance, a prioritization methodology is needed for the selection of those to be monitored. Existing well-developed models require significant amount of data for reliable outcomes. This paper presents a methodology to prioritize the dangerous substances having adverse effects on freshwaters in Turkey, where data are scarce. Such a methodology will also serve as a solid model for other countries with limited background data. The adopted methodology enabled the elimination of chemicals to generate a candidate list composed of 608 substances among more than 5000 substances. Further screening and prioritization were conducted using different assessment methods (i.e., Total Hazard Value, Total Impact Value, Combined Monitoring-based, and Modelling-based Priority Setting) to obtain a proposed Final Candidate Specific Pollutants List of 150 dangerous substances. The proposed Candidate National Pollutant List of Turkey was established by combining 45 priority pollutants of the European Union with a list of candidate specific pollutants. According to the outcomes of this study, monitoring and controlling of 195 dangerous substances in freshwaters are recommended. Further detailed studies should be conducted in order to observe the actual levels of these dangerous substances in freshwaters followed by a review of the monitoring list accordingly. Moreover, further revisions might be required in the proposed list due to some possible versatile conditions in terms of sampling points (i.e., change in the location of industries).  相似文献   
43.
The sorption conditions including pH of the aqueous solution, sample volume, etc., on Celtek clay of copper(II), cadmium(II), lead(II), chromium(III), nickel(II) and cobalt(II) ions from environmental samples has been studied. The effects of electrolytes as matrix on the preconcentration were also investigated with the recoveries >95%. The 3 sigma detection limits for copper, cadmium, lead, chromium, nickel and cobalt ions were found to be 0.25, 0.32, 0.73, 0.45, 0.50 and 0.41 microg/l, respectively. The relative standard deviation was <10% for the determination of analytes. The procedure was validated by analysis of a NRCC-SLRS 4 Riverine Water, SRM 1573a Tomato leaves and IAEA 336 Lichen standard reference materials. The developed method was successively utilized for the determination of Cu(II), Cd(II), Pb(II), Cr(III), Ni(II) and Co(II) in various samples including natural waters, wheat and human hair by flame atomic absorption spectrometry (FAAS) with satisfactorily results (recoveries>95% and R.S.D.'s<10%).  相似文献   
44.
Gündoğan  Esra  Kaya  Mehmet 《Scientometrics》2022,127(7):3837-3855
Scientometrics - Every year, thousands of papers are published in journals and conferences by researchers in many different fields. These papers are an important guide for other researchers....  相似文献   
45.
Fragility curves are used to represent the probabilities that the structural damages, under various level of seismic excitation, exceed specified damage states by means of earthquake intensity–damage relations. In this study, the fragility curves have been developed for comparative seismic evaluation of several retrofitting measures by incorporation of fluid viscous (VS) dampers applied to a representative high-rise reinforced concrete (R/C) office building located in Istanbul. In the retrofitting strategies considered, similar type of VS dampers was used and designed to provide the structure with three different effective damping ratios of 10%, 15%, and 20%. In the fragility analysis, a set of 240 artificially generated earthquake ground motions compatible with the design spectrum selected to represent the variability in ground motion was employed to study nonlinear dynamic responses of the structures before and after retrofit. Four damage states: slight, moderate, major, and collapse were defined to express the condition of damage. The fragility curves in this study are represented by lognormal distribution functions with two parameters and developed as a function of peak ground acceleration (PGA), spectral acceleration (Sa), spectral displacement (Sd). Comparison of the fragility curves indicated that the VS dampers were very effective in attenuating seismic structural response under various earthquake ground motions. It was also found that a two-fold reduction in the probability of exceeding damage states might be achieved by introducing passive VS damper systems.  相似文献   
46.
The effective atomic numbers of compounds of the first row transition elements were determined experimentally by a scattering method using wavelength dispersive X-ray fluorescence spectrometer. A calibration curve was created by using the intensity ratios of coherent to Compton scattered peaks of pure elements from atomic number 13–48. This relationship was employed to determine the effective atomic numbers of the compounds. The effective atomic numbers were also calculated by using empirical formulas from the literature. Mass attenuation coefficients were calculated using software. The experimentally measured values of the effective atomic numbers with the calculated values by empirical formulas were comparable.  相似文献   
47.
This study analyzes the exposure of the human torso to electromagnetic fields caused by wireless body-mounted or handheld devices. Because of the frequency and distance ranges from 30-5800 MHz and 10 to 200 mm, respectively, both near-field and far-field effects are considered. A generic body model and simulations of anatomical models are used to evaluate the worst case tissue composition with respect to the absorption of electromagnetic energy. Both standing wave effects and enhanced coupling of reactive near-field components can lead to a specific absorption rate (SAR) increase in comparison to homogeneous tissue. In addition, the exposure and temperature increase of different inner organs is assessed. With respect to compliance testing, the observed SAR enhancement may require the introduction of a multiplication factor for the spatial peak SAR measured in the liquid-filled phantom in order to obtain a conservative exposure assessment. The observed tissue heating at the body surface under adiabatic conditions can be significant, whereas the temperature increase in the inner organs turned out to be negligible for the cases investigated.  相似文献   
48.
In this study, to evaluate the in vitro bioaccessibility of eight different pekmez and pestil samples, total phenolics, flavonoids, proanthocyanidins, anthocyanins and antioxidant capacity were determined at different phases of simulated gastrointestinal (GI) digestion. For the analysis of antioxidant activity, four different methods were used including 2,2‐azinobis(3‐ethylbenzothiazoline)‐6‐sulfonic acid, 1,1‐diphenyl‐2‐picrylhydrazil, ferric reducing antioxidant power and cupric ion reducing antioxidant capacity. The results revealed that the dialysed fraction (IN) represented 12–50%, 3–17% and 3–72% of the total phenolics, flavonoids and proanthocyanidins, respectively. Moreover, total antioxidant capacity of IN fraction was 2–57% of the initial values obtained for pekmez and pestil samples. To identify the influence of simulated in vitro GI digestion on total anthocyanins, only black mulberry molasses (pekmez) and plum leather (pestil) were analysed and according to the results no anthocyanins were detected in the IN fraction for both samples. The present study presented a detailed insight of bioaccessibility of polyphenols in various pekmez and pestil samples.  相似文献   
49.
50.
In the design of hearing aids (HA), the real-time speech-enhancement is done. The digital hearing aids should provide high signal-to-noise ratio, gain improvement and should eliminate feedback. In generic hearing aids the performance towards different frequencies varies and non uniform. Existing noise cancellation and speech separation methods drops the voice magnitude under the noise environment. The performance of the HA for frequency response is non uniform. Existing noise suppression methods reduce the required signal strength also. So, the performance of uniform sub band analysis is poor when hearing aid is concern. In this paper, a speech separation method using Non-negative Matrix Factorization (NMF) algorithm is proposed for wavelet decomposition. The Proposed non-uniform filter-bank was validated by parameters like band power, Signal-to-noise ratio (SNR), Mean Square Error (MSE), Signal to Noise and Distortion Ratio (SINAD), Spurious-free dynamic range (SFDR), error and time. The speech recordings before and after separation was evaluated for quality using objective speech quality measures International Telecommunication Union -Telecommunication standard ITU-T P.862.  相似文献   
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