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排序方式: 共有204条查询结果,搜索用时 24 毫秒
101.
Giampiero Sanguigni 《世界建筑导报》2009,24(4):16-21
盐酸情人 关注细节、书法、肉体谜恋、自毁--如果把盖天柯(Francesco Gatti)的"in Factory"与彼得格林纳威(Peter Greenaway)的<枕边禁书>还有中国作家棉棉的<九个目标的欲望>放在一起比较的话,以上词汇便会跃入脑海. 相似文献
102.
A hybrid numerical technique based on the finite-element method (FEM) is exploited to define a numerical diffraction coefficient for irregular wedge configurations as, for instance, a perfectly conducting wedge with an inhomogeneously filled cavity-backed aperture in one of its faces, or a wedge with a rounded edge. The hybrid technique combines the FEM with the uniform geometrical theory of diffraction (UTD), and is used to develop a numerical diffraction coefficient to account for contributions to the scattered field due to localized inhomogeneities in an otherwise canonical perfectly conducting wedge 相似文献
103.
Effect of blanching in water and sugar solutions on texture and microstructure of sliced carrots 总被引:1,自引:0,他引:1
Thermal processing of vegetables has pronounced effects on the cell structure, often negatively affecting the final textural properties of the product. In order to study the effect of thermal processing and the protective effect of sugars on the tissue, sliced carrots were subjected to blanching treatments under different time and temperature combinations both in water and in 4% sugar solutions made of trehalose or maltose. The influence of these process conditions on mass transfer, texture, and microstructure (Cryo-scanning electron microscopy) was thus investigated. The total mass loss of all the samples blanched in water was associated to their cook value (C(100)(18)) except for the overprocessed one (90 °C, 10 min) that showed a total mass change significantly lower due to water uptake. The use of trehalose and maltose in the blanching solution reduced the solute loss while increasing the water loss. Microstructural analysis of the differently blanched carrots showed detachments between adjacent cell walls as well as plasmolysis phenomena as the time and temperature of the thermal treatment were increased. A protective effect of both sugars on cell structures was observed mostly in the sample treated at 90 °C. At macroscopic level, textural changes upon blanching were observed by a penetration test. As blanching time was increased, samples processed at 75 °C showed a hardness increase, while those processed at 90 °C showed a hardness decrease. However, both trehalose and maltose did not exert significant effects on the textural properties of blanched carrots when compared with those blanched in water. Practical Application: The results of this study could offer interesting perspectives in the optimization of the heat treatments in order to preserve the quality of semi-finished processed vegetables. Furthermore, the microstructural analysis is nowadays an important investigation tool that could contribute to a deeper understanding of both the effects of processing and ingredients on the vegetable microstructure and its relationship with the changes occurring on the quality properties at macroscopic level. 相似文献
104.
In this paper, a couple of path gain models for on-body communication systems are analyzed and compared. The study is focused on the characterization of the propagation channel between two wearable devices placed on a human body, and operating at 2.4 and 5.8 GHz. Wearable wireless low-cost commercial modules and low-profile annular ring slot antennas were used, and measurements were performed for different radio links on a human body. Measurement results have been compared with CST Microwave Studio simulations by resorting to simplified body models like flat, cylindrical, spherical, and ellipsoidal canonical geometries. Characteristic parameters appearing in the propagation models have been calculated for the analyzed on-body channels and summarized in a concluding table. 相似文献
105.
Scientometrics - Basic research creates new knowledge that fuels technological advances. However, budgetary concerns and escalating R&D prices are challenging organizations to show returns... 相似文献
106.
Austin D. Stanfield Dario Manara Davide Robba Gregory E. Hilmas William G. Fahrenholtz 《Journal of the American Ceramic Society》2021,104(6):2780-2787
The melting temperatures of two different ZrB2 ceramics were studied using laser induced melting. ZrB2 having a low Hf content, produced by reaction hot pressing, had a melting temperature of 3546 K and a commercial grade ZrB2 had a melting temperature of 3553 K. Uncertainty of the temperature measurements was 1% of the absolute temperature, or ~35 K for both materials based upon 2-sigma and a 95% confidence interval. While these values were consistent with the previously reported ZrB2 melting temperature of 3518 K, this study was able to measure Tm with less uncertainty than previous studies (±45 K). Furthermore, this study assessed the effect of Hf content on melting temperature, finding that melting temperature did not change significantly for hafnium contents of 1.75 to 0.01 at%. This study also measured a normal spectral emissivity of 0.34 for ZrB2 at 3000 K. The emissivity decreased to 0.28 at the melting temperature, then, stabilized at 0.30 in a liquid phase. 相似文献
107.
Wastewater treatment leads to an increase in sewage sludge production. Sewage sludge consists, in general, of non-toxic organic matter and therefore can be utilized as a biomass resource for energy production. Energy recovery from sewage sludge via thermochemical valorization processes seems of great potential. Processes’ products can be used as bio-fuels, while minimization of the environmental impacts can be also achieved. In particular, wet sewage sludge pyrolysis-partial gasification at high temperatures and especially gasification give a new perspective for hydrogen-rich fuel gas production. Co-processing of sewage sludge with biomass improves the fuel's characteristics and enhances the processes efficiency. In addition, blends of sewage sludge with biomass contribute in diluting the inorganic and toxic compounds. Towards that direction, algae production using wastewater resources and then to be used for biofuels production seems a sustainable solution that is the reason why exploitation of such a material through thermochemical processes is under intensive discussion. 相似文献
108.
109.
Andrea Piva Carla Di MattiaLilia Neri Gloria DimitriMarco Chiarini Giampiero Sacchetti 《Food chemistry》2008
Cooked must is a product that could be used in food formulations, directly or after fermentation, to obtain many traditional foods. Must cooking was conducted in boilers of different materials (copper and stainless steel) for different times in order to obtain differently concentrated products. 相似文献
110.
The antioxidant activity of the hydrophilic and lipophilic fraction of poultry meat was determined in terms of ‘radical scavenging activity’ (RSA) using a modified ABTS radical cation decolorization method.The method uses the extraction of hydrophilic and lipophilic fractions in water and methanol–chloroform, respectively. The determination of the RSA of the lipophilic fraction was conducted using a chloroform extract and maintaining a constant chloroform:ethanol ratio in the solution of analysis. The method was tested on nine samples of poultry breasts and thigh meats and permitted to quantify the RSA in terms of μmol Trolox equivalent antioxidant capacity (TEAC) with a mean relative standard deviation of less than 5%.The contribution of the hydrophilic fraction to the total RSA was much higher than that of the lipid soluble fraction. Breast showed a higher RSA than thigh meat due to its lower total lipids content. The total RSA value (TEAC = 2.4 μmol g−1) suggests that poultry meat could significantly contribute to the antioxidant activity of the diet. 相似文献