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411.
Ion Anghel Carmen Limban Alexandru Mihai Grumezescu Alina Georgiana Anghel Coralia Bleotu Mariana Carmen Chifiriuc 《Nanoscale research letters》2012,7(1):513
In this paper, we report the design of a new nanofluid for anti-pathogenic surface coating. For this purpose, new 2-((4-ethylphenoxy)methyl)-N-(substituted-phenylcarbamothioyl)-benzamides were synthesized and used as an adsorption shell for Fe3O4/C12 core/shell nanosized material. The functionalized specimens were tested by in vitro assays for their anti-biofilm properties and biocompatibility. The optimized catheter sections showed an improved resistance to Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853 in vitro biofilm development, as demonstrated by the viable cell counts of biofilm-embedded bacterial cells and by scanning electron microscopy examination of the colonized surfaces. The nanofluid proved to be not cytotoxic and did not influence the eukaryotic cell cycle. These results could be of a great interest for the biomedical field, opening new directions for the design of film-coated surfaces with improved anti-biofilm properties. 相似文献
412.
Alexandru Mihai Bica 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2007,11(11):1099-1105
Using a classic algebraic construction additive and multiplicative structures (as commutative monoids) for fuzzy numbers are
obtained. Moreover, we realize here an isomorphism between these structures. 相似文献
413.
Sinziana Popescu Mihai Bogdan Preda Catalina Iolanda Marinescu Maya Simionescu Alexandrina Burlacu 《International journal of molecular sciences》2021,22(11)
Mesenchymal stromal cells (MSC) are promising candidates for regenerative therapy of the infarcted heart. However, poor cell retention within the transplantation site limits their potential. We hypothesized that MSC benefits could be enhanced through a dual-cell approach using jointly endothelial colony forming cells (ECFC) and MSC. To assess this, we comparatively evaluated the effects of the therapy with MSC and ECFC versus MSC-only in a mouse model of myocardial infarction. Heart function was assessed by echocardiography, and the molecular crosstalk between MSC and ECFC was evaluated in vitro through direct or indirect co-culture systems. We found that dual-cell therapy improved cardiac function in terms of ejection fraction and stroke volume. In vitro experiments showed that ECFC augmented MSC effector properties by increasing Connexin 43 and Integrin alpha-5 and the secretion of healing-associated molecules. Moreover, MSC prompted the organization of ECFC into vascular networks. This indicated a reciprocal modulation in the functionality of MSC and ECFC. In conclusion, the crosstalk between MSC and ECFC augments the therapeutic properties of MSC and enhances the angiogenic properties of ECFC. Our data consolidate the dual-cell therapy as a step forward for the development of effective treatments for patients affected by myocardial infarction. 相似文献
414.
Tanja Vidaković Mihai Christov Kai Sundmacher 《Journal of Applied Electrochemistry》2009,39(2):213-225
A method for a rough estimation of the catalyst surface area in a fuel cell is developed. It is based on the deconvolution
of experimental CO oxidation data by use of a mathematical model. The kinetic parameters of the model are determined by fitting
the experimental curves. The experimental data are collected at different sweep rates (2–100 mV s−1) and at different temperatures (room −60.0 °C). The model can predict the sweep rate dependence of the CO oxidation onset
potential, the peak current, the peak potential and the peak broadness. The model is further used for the prediction of the
baseline in the presence of CO and for calculation of the CO charge consumed up to half peak potential. It is obtained that
the latter value is constant at different sweep rates and that the baseline deviates from linearity already at low sweep rates
(2 mV s−1), but not very significantly (2.0% in comparison to 8.8% at 100 mV s−1, based on calculated CO charge). It is suggested that lower sweep rates should be used for experimental surface area determination. 相似文献
415.
Septimius Mara Mihai Tanasescu Alexandru Ozunu Serban Nicolae Vlad 《Mine Water and the Environment》2007,26(4):256-263
Damage caused by accidents at hydraulic structures, due to natural hazards or human causes (e.g. terrorist sabotage) can be
comparable to those caused by natural disasters. The paper identifies the major advantages of a common methodology for risk
identification and quantification regarding the potential impact of accidents at tailings dams on the environment. Relevant
Romanian and EU legislation and regulations enacted following the “Baia Mare” accident in 2000 are reviewed, along with a
common risk evaluation methodology that can be applied by the mining sector to tailings dams. 相似文献
416.
Spatio-temporal reconstruction of bilateral auditory steady-state responses using MEG beamformers 总被引:1,自引:0,他引:1
Popescu M Popescu EA Chan T Blunt SD Lewine JD 《IEEE transactions on bio-medical engineering》2008,55(3):1092-1102
A rapidly growing number of neuromagnetic studies focus on the analysis of auditory steady-state responses (ASSR) in relation to a diverse array of factors including age, selective attention, and presence of psychopathology. The objectives of these studies require accurate spatio-temporal estimation of the underlying neural generators, a challenging task due to the relatively low signal strength and high correlation between bilateral auditory cortical sources. This paper evaluates the performance of two beamforming schemes that can potentially overcome such difficulties: 1) the linearly constrained minimum variance beamformer with partial sensor coverage (LCMV-PSC), and 2) the multiple constrained minimum-variance beamformer with coherent source region suppression (MCMV-CSRS). Simulation experiments are conducted to assess the impact of source parameters on the reconstruction accuracy. The results indicate that the LCMV-PSC method is prone to localization errors that essentially occur along medio-lateral directions, increase with source depth, and are associated to amplitude and phase distortions of the estimated time courses of activity. Comparatively, the MCMV-CSRS method exhibits precise localization and minimal amplitude and phase distortion for a broad range of relative interferer's positions within the suppression region. The results from the numerical experiments are validated on real magnetoencephalographic (MEG) data collected from a 40-Hz ASSR paradigm. 相似文献
417.
Matteo Ferro Ottavio de Cobelli Mihai Dorin Vartolomei Giuseppe Lucarelli Felice Crocetto Biagio Barone Alessandro Sciarra Francesco Del Giudice Matteo Muto Martina Maggi Giuseppe Carrieri Gian Maria Busetto Ugo Falagario Daniela Terracciano Luigi Cormio Gennaro Musi Octavian Sabin Tataru 《International journal of molecular sciences》2021,22(18)
Radiomics and genomics represent two of the most promising fields of cancer research, designed to improve the risk stratification and disease management of patients with prostate cancer (PCa). Radiomics involves a conversion of imaging derivate quantitative features using manual or automated algorithms, enhancing existing data through mathematical analysis. This could increase the clinical value in PCa management. To extract features from imaging methods such as magnetic resonance imaging (MRI), the empiric nature of the analysis using machine learning and artificial intelligence could help make the best clinical decisions. Genomics information can be explained or decoded by radiomics. The development of methodologies can create more-efficient predictive models and can better characterize the molecular features of PCa. Additionally, the identification of new imaging biomarkers can overcome the known heterogeneity of PCa, by non-invasive radiological assessment of the whole specific organ. In the future, the validation of recent findings, in large, randomized cohorts of PCa patients, can establish the role of radiogenomics. Briefly, we aimed to review the current literature of highly quantitative and qualitative results from well-designed studies for the diagnoses, treatment, and follow-up of prostate cancer, based on radiomics, genomics and radiogenomics research. 相似文献
418.
Iulian Riposan Mihai Chisamera Stelian Stan Chris Ecob David Wilkinson 《Journal of Materials Engineering and Performance》2009,18(1):83-87
A research was done to investigate the effect of strong deoxidizing elements, such as Al, Zr, and Ti, in gray irons in laboratory
experiments. The conclusions drawn were based mainly on thermal analysis, chill (carbides) sensitivity, graphite characteristics,
and SEM analysis. Al and Zr have visible beneficial effects in preconditioning of gray irons, by favoring lower undercooling
during solidification. Ti has an inconclusive role, with limited influence, but promotes undercooled graphite formation. Complex
(Mn,X)S compounds, nucleated on the previously formed small oxide-based sites, were found as the major nucleation sites for
graphite in gray irons, with specific distribution of Al, Ti, and Zr. Al,Zr-FeSi preconditioning of electrically melted and
Sr-FeSi inoculated gray irons avoided type D graphite and carbides in 3 mm sections castings. 相似文献
419.
This work provides a practical application of a coupled experimental-computational system devised for the full characterization of the thermal behavior of complex three-dimensional active submicron electronic devices. A thermoreflectance thermography (TRTG) technique is used to non-invasively measure the 2D surface temperature field of an activated device, with submicron spatial resolution. The measured planar temperature distribution field is then used as input for an ultra-fast inverse computational solution to derive the three-dimensional temperature distribution throughout the device. For the purposes of this investigation, test micro-heater devices were constructed on epitaxial layers of natural (Si) and isotopically pure (Si28) silicon. Then, all devices were activated and measured with the TRTG technique. In order to demonstrate the coupled experimental-computational system, the measured temperature fields of the samples whose thermal properties are known (Si) were used to extract critical physical parameters (the oxide layer thickness and the effective heater length). Then, since the devices with unknown thermal properties (Si28) share the same construction with the Si devices, the extracted parameters were used together with the measured planar temperature fields to derive the thermal conductivity of Si28. The extracted oxide layer thickness and thermal conductivity of Si28 compared very closely to values obtained by other independent direct methods. 相似文献
420.
General adaptive-neighborhood technique for improving synthetic aperture radar interferometric coherence estimation 总被引:2,自引:0,他引:2
Vasile G Trouvé E Ciuc M Buzuloiu V 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(8):1455-1464
A new method for filtering the coherence map issued from synthetic aperture radar (SAR) interferometric data is presented. For each pixel of the interferogram, an adaptive neighborhood is determined by a region-growing technique driven by the information provided by the amplitude images. Then pixels in the derived adaptive neighborhood are complex averaged to yield the filtered value of the coherence, after a phase-compensation step is performed. An extension of the algorithm is proposed for polarimetric interferometric SAR images. The proposed method has been applied to both European Remote Sensing (ERS) satellite SAR images and airborne high-resolution polarimetric interferometric SAR images. Both subjective and objective performance analysis, including coherence edge detection, shows that the proposed method provides better results than the standard phase-compensated fixed multilook filter and the Lee adaptive coherence filter. 相似文献