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51.
The aim of this study was to describe the dependence of hardness of processed cheeses on the proportion of disodium hydrogenphosphate (DSP), tetrasodium diphosphate (TSPP) and/or sodium salts of polyphosphate (POLY) in ternary mixtures of emulsifying salts. The samples were observed during a 30‐day storage period (at 6 °C). On the second day of storage, hardness of the samples with the individual DSP, TSPP or POLY were in the range of 1.65–1.83 N, 2.42–2.81 N and 5.98–6.53 N, respectively. Within zero or a very low proportion of POLY in the mixture, hardness of the processed cheeses increased rapidly (up to 14 N) at a specific ratio of DSP to TSPP in range of 1:1–3:4. Hardness of the samples containing the above‐mentioned specific ratio was decreasing with the rising content of POLY (up to 60%) in the ternary mixtures. Within the prevailing content of POLY in the ternary mixtures (more than 60%), the phenomenon of a specific ratio of DSP to TSPP was no longer observed. With the increasing storage period (up to 30 days), hardness of the processed cheeses was slightly rising (in range of 2–4 N).  相似文献   
52.
Crystalline Bi5NbO10 nanoparticles have been achieved through a modified sol–gel process using a mixture of ethylenediamine and ethanolamine as a solvent. The Bi5NbO10 nanoparticles were characterized by X-ray diffraction (XRD), differential scanning calorimetry/thermogravimetry (DSC/TG), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and Raman spectroscopy. The results showed that well-dispersed 5–60 nm Bi5NbO10 nanoparticles were prepared through heat-treating the precursor at 650 °C and the high density pellets were obtained at temperatures lower than those commonly employed. The frequency and temperature dependence of the dielectric constant and the electrical conductivity of the Bi5NbO10 solid solutions were investigated in the 0.1 Hz to 1 MHz frequency range. Two distinct relaxation mechanisms were observed in the plots of dielectric loss and the imaginary part of impedance (Z″) versus frequency in the temperature range of 200–350 °C. The dielectric constant and the loss in the low frequency regime were electrode dependent. The ionic conductivity of Bi5NbO10 solid solutions at 700 °C is 2.86 Ω?1 m?1 which is in same order of magnitude for Y2O3-stabilized ZrO2 ceramics at same temperature. These results suggest that Bi5NbO10 is a promising material for an oxygen ion conductor.  相似文献   
53.
Magnetic Resonance Materials in Physics, Biology and Medicine - T2 maps are more vendor independent than other MRI protocols. Multi-echo spin-echo signal decays to a non-zero offset due to...  相似文献   
54.
Atherosclerosis is a progressive disease characterized by the accumulation of lipids and fibrous elements in arteries. It is characterized by dysfunction of endothelium and vasculitis, and accumulation of lipid, cholesterol, and cell elements inside blood vessel wall. In this study, a continuum-based approach for plaque formation and development in 3-D is presented. The blood flow is simulated by the 3-D Navier-Stokes equations, together with the continuity equation while low-density lipoprotein (LDL) transport in lumen of the vessel is coupled with Kedem-Katchalsky equations. The inflammatory process was solved using three additional reaction-diffusion partial differential equations. Transport of labeled LDL was fitted with our experiment on the rabbit animal model. Matching with histological data for LDL localization was achieved. Also, 3-D model of the straight artery with initial mild constriction of 30% plaque for formation and development is presented.  相似文献   
55.
The paper presents a working electrical scheme modeling the memristor. The scheme allows experimenting with the model under various testing signals. The user can use it to verify the theoretical presumptions about the memristor properties. Examples of several typical measurements are shown. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
56.
A new circuit topology of first-order voltage-mode all-pass filter providing high-input and low-output impedances is described. The filter consists of only one grounded capacitor and one active element, namely VD-DIBA (Voltage Differencing-Differential Input Buffered Amplifier), with the possibility of electronically tuning the natural frequency. The filter is assembled from commercial integrated circuits, and the frequency responses measured are compared with the theoretical characteristics.  相似文献   
57.
Positron annihilation spectroscopy was employed for the microstructure characterization of rapidly solidified Al-3 wt.% Cr-3 wt.% Fe-0.8 wt.% Ce alloy prepared by melt spinning. Results of the positron annihilation study are analyzed within the diffusion trapping model and compared with results of X-ray diffraction, transmission electron microscopy and microhardness measurements. A good consistency among all experimental techniques was obtained. The rapidly solidified alloy exhibits ultra fine grained structure, consisting of cells separated by dislocation walls. Annealed samples showed no significant changes in structure up to 400 °C which proves good thermal stability of ultra fine grained structure. Exposure of the sample to temperature of 500 °C caused significant changes in the material.  相似文献   
58.
Low-voltage (LV) low-power (LP) integrated circuit design is becoming a leading trend in VLSI technology, particularly in special portable applications. In this paper, the principle of a bulk-driven MOS transistor is employed in the design of a novel LV LP current differencing transconductance amplifier (CDTA). Designs in the 0.25 μm CMOS technology have been verified via PSpice simulation. The supply voltages are only ±0.6 V.  相似文献   
59.
The aviation organization is creating awareness for the overall reduction of NOx emissions by up to 80% in the near future. This motivates to conduct research on the current state of art, catalytic stabilized combustion chamber using hydrogen. This was achieved by performing an experimental parametric investigation of Platinum catalysts in two phases. Firstly, the design of three diverse configurations of mixers and was investigated experimentally and numerically. The chosen mixer was implemented in the parametric study of five different Pt catalysts varying in geometric and material properties. This was executed at unpressurized and NOx emission solely due to the catalytic reaction was examined for varying thermal power and air/fuel ratios. Furthermore, temperatures were recorded. Additionally, CFD simulation was accomplished and compared with the measurement data. The overall least NOx achieved was 7.5  ppm at 5 kW for the metal catalyst. The result of this work proposed suitable catalyst for the development of a combined combustor configuration (including catalyst and combustion chamber) which will be intended for small aircraft engine applications.  相似文献   
60.
Microstructure and magnetic properties of nanoparticles can be tailored by optimising the synthesis procedure and changing chemical composition. In this study, a two-step procedure, i.e., coprecipitation in the presence of PEG 300 followed by microwave assisted (MW) hydrothermal synthesis, was introduced to obtain CoxFe3-xO4 (x?=?0, 0.1 and 0.2) nanoparticles. It was found that with the increase of Co content, particle/crystallite size increased, with significant change of coercivity (Hc). The mixed samples of CoxFe3-xO4 (x?=?0.1 and 0.2) were magnetically harder in comparison with Fe3O4. Тhe Hc of Fe3O4 was 91?Oe, while for Co0.10Fe2.90O4 and Co0.20Fe2.80O4, Hc was 256?Oe and 1070?Oe, respectively. Saturation magnetisation (Ms) of mixed samples also increased up to 6% compared to Fe3O4. A special effort was devoted to study the effects of introducing different surfactants (PEG 300, PEG 4000 or SDS) during the synthesis procedure in order to improve morphological and microstructural properties of CoFe2O4 nanoparticles. The influence of surfactants on physical/chemical properties of nanoparticles is discussed.  相似文献   
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