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排序方式: 共有189条查询结果,搜索用时 15 毫秒
1.
Ovalbumin (OV), bovine serum albumin (BSA) and lysozyme (Lys) were added to egg yolk low density lipoprotein (LDL) and the heat-induced gel formation of LDL-protein mixture was studied. The gel formation of LDL-protein mixture was different between the acidic and alkaline pH region; fine stable gels were formed in the alkaline pH region, but weak paste-like gels were formed in the acidic pH region. The effect of added BSA or OV on the gel strength of LDL was much larger than that of Lys. Scanning electron micrographic observation showed that the microstructures of both LDL-BSA and LDL-OV gels were more uniform than that of LDL-Lys gel.  相似文献   
2.
The mechanism of colour change during the pigment dispersion process and during powder application to the skin surface was studied by examining the colour extension properties of Yellow. Red , and Black iron oxides in white powder bases. A new measure for the evaluation of the degree of colour extension was devised. This measure corresponded well with human visual sensation, and was found to be useful for comparing the rates of colour extension of pigments. The rate of colour extension of pigments was found to vary in the order: Yellow acicular Red granular Red Black. This result explains colour darkening and the change towards reddish tones during the pigment dispersion process, because Yellow extends fully in the early stage of the process but Red , especially in granular form, and Black continue to extend even in the later stage. Acicular Red iron oxide is more favourably employed than the granular form to attain sufficient colour extension of foundations with lower energy expenditure, and to decrease the discrepancy between the cake colour and the colour of applied powder.
Le développement des oxydes de fer et effet sur les nuances des fonds de teint compacts  相似文献   
3.
Thermal decomposition of mullite into corundum was investigated using a high-temperature X-ray single-crystal camera equipped with a gas-flame furnace and by scanning electron microscopy and electron probe microanalysis (EPMA). When heated to ∼1750°C, mullite decomposed to corundum by the liberation of the SiO2 component with topotaxial relations of:
  • (1) 

    (310)mull∥(001)cor; [001]mull∥[110]cor

  • (2) 

    (130)mull∥(001)cor; [001]mull∥[110]cor

  • (3) 

    (110)mull∥(001)cor; [001]mull∥[110]cor


Thus, it was considered that, when mullite decomposed into corundum, their oxygen close-packed planes were almost preserved. The SEM photographs showed that the crystals of the developed corundum are prismatic and ∼5 μm wide. The EPMA showed that the phase boundary between mullite and developed corundum is discontinuous.  相似文献   
4.
This paper presents an advanced resonant ultrasound spectroscopy (RUS) method to determine the elastic constants Cij of thin films. Polycrystalline thin films often exhibit elastic anisotropy between the film growth direction and the in‐plane direction, and they macroscopically show five independent elastic constants. Because all of the Cij of a deposited thin film affect the mechanical resonance frequencies of the film/substrate layer specimen, measuring resonance frequencies enables one to determine the Cij of the film with known density, dimensions and the Cij of the substrate. Resonance frequencies have to be measured accurately because of low sensitivity of the Cij of films to them. We achieved this by a piezoelectric tripod. Mode identification has to be made unambiguously. We made this measuring displacement–amplitude distributions on the resonated specimen surface by laser Doppler interferometry. We applied our technique to copper thin film and diamond thin film. They show elastic anisotropy and the Cij smaller than bulk values of Cij. Micromechanics calculations indicate the presence of incohesive bonded regions.  相似文献   
5.
Fractional‐slot windings are widely used in rotating machines in order to improve the output voltage waveform, increase the design flexibility, and gain many other advantages. However, fractional‐slot windings are known to produce different harmonic components such as an even order and/or fractional number of space flux harmonics compared to integral‐slot windings. These harmonics may increase stray losses and cause stator core vibration. This paper describes an analysis of space flux harmonics and proposes new winding methods such as “novel interspersed windings” to reduce these harmonic components. The proposed winding methods were verified by numerical analysis and model tests.  相似文献   
6.
Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular, owing to their short cruising distance and long charging time. Wireless power transfer from the infrastructure to running EVs is expected to be the solution to these problems. Electric vehicle and electrified roadway (EVER) has been proposed as a wireless power transfer system for EVs while in motion. Via‐wheel power transfer (V‐WPT) is expected to be a wireless power transfer scheme for EVER. We designed and prototyped a 1:32 scale model of a V‐WPT system that consists of an RF inverter, an electrified roadway, a rectifier, and an EV with a dc motor. The output power of the prototype RF inverter was 5.9 W and the dc–RF conversion efficiency was 36.6%. The LC matching circuits for the V‐WPT were designed with two‐port conjugate matching because S11 of the V‐WPT was intrinsically –0.06 dB. After matching, the S11 value was reduced to –21.5 dB. The power transmission efficiency of the V‐WPT system was 75%. The RF–dc conversion efficiency of the rectifier was 62%. The total efficiency of the EVER system was 24.2%.  相似文献   
7.
Computed tomography (CT) was performed on Gouda‐type cheese during ripening to evaluate gas hole formation and structural quality. The cheese was exposed to different ripening conditions, including variations in ripening temperature and concentration of butyric acid bacteria. Computed tomography images were obtained every 2 weeks for 16 weeks to assess the volume, shape and location of gas holes. The results demonstrate that CT makes the nondestructive monitoring of cheese gas hole formation and evaluation of the structural features of cheese possible throughout the ripening period.  相似文献   
8.
针对日本国鬼怒河流域小流量河流,通过对河床上附着生物膜的组成、底栖生物、细菌活性分析和AGP试验,研究了污水厂二级处理排放水对小流量河流生态的影响.研究表明,当污水厂二级处理排放水占河流流量比例较大时(研究河流所占比例为35%),同样会引发河流富营养化和影响河流水体的生态.因此,从保护水环境及其生态考虑,有必要对污水进行深度处理.  相似文献   
9.
A thermo gravimetric study of the oxidation behavior of chemically vapor-deposited amorphous and crystalline Si3N4 (CVD Si3N4) was made in dry oxygen (0.1 MPa) at 1550° to 1650°C. The specimens were prepared under various deposition conditions using a mixture of SiCl4, NH3, and H2 gases. The crystalline CVD Si3N4 indicated a parabolic oxidation kinetics over the whole temperature range, whereas the amorphous CVD Si3N4 changed from a parabolic to a linear law with increased temperature. The oxidation mechanism is discussed in terms of the activation energy for the oxidation and the microstructure of the formed oxide films.  相似文献   
10.
A new high repetition rate Nd:YAG Thomson scattering system is developed for the Heliotron J helical device.A main purpose of installing the new system is the temporal evolution measurement of a plasma profile for improved confinement physics such as the edge transport barrier (H-mode) or the internal transport barrier of the helical plasma.The system has 25 spatial points with ~10mm resolution.Two high repetition Nd:YAG lasers (>550mJ@ 50Hz) realize the measurement of the time evolution of the plasma profile with ~10ms time intervals.Scattered light is collected by a large concave mirror (D=800 mm,f/2.25) with a solid angle of ~100 mstr and transferred to interference filter polychromators by optical fiber bundles in a staircase form.The signal is amplified by newly designed fast preamplifiers with DC and AC output,which reduces the low frequency background noise.The signals are digitized with a multi-event QDC,fast gated integrators.The data acquisition is performed by a VME-based system operated by the CINOS.  相似文献   
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