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排序方式: 共有4144条查询结果,搜索用时 46 毫秒
981.
Mayra Díaz‐Ramírez Georgina Calderón‐Domínguez J. Jorge Chanona‐Pérez Arturo Janovitz‐Klapp Rubén López‐Santiago Reynold R. Farrera‐Rebollo Ma de la Paz Salgado‐Cruz 《International Journal of Food Science & Technology》2013,48(8):1649-1660
Sponge cake is an ideal product to be soaked with liquids, due to its porous structure; baking process causes differences in crumb features through the cake; therefore, it is important to know how these variations can affect its sorption capacity. The aim of this work was to study the relation between crumb cake structure at different levels (bottom, centre and top) and sorption characteristics when adding milk syrup. The Peleg model was the best to fit sorption data (R2 > 0.9), showing that the rate constant (k1) diminished as the cell density (r = 0.920) and gelatinisation percentage (r = 0.890) decreased, while moisture (r = ?0.999) and aw (r = ?0.994) increased; cell density only correlated with gelatinisation percentage (r = 0.997); micrographs showed that the sorption rate increased as more gelatinised starch and coagulated protein were found. To optimise the sorption process, the gelatinisation degree and crumb structure (cell density and types of pores) should be considered. 相似文献
982.
Felipe L. Penaranda‐Foix Jose M. Catala‐Civera Antoni J. Canós Beatriz Garcia‐Banos 《国际射频与微波计算机辅助工程杂志》2015,25(6):530-535
This article proposes the use of argument principle method (APM) to find all complex resonant frequencies in a three layer cylindrical cavity. APM guarantees that no root is lost and frequencies can be associated with the resonant mode. The roots can be used to find permittivity of a material inside a cavity. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:530–535, 2015. 相似文献
983.
Ram Ranjan Abhijeet Patel Suresh V. Garimella Jayathi Y. Murthy 《International Journal of Heat and Mass Transfer》2012,55(4):586-596
The thermal and hydrodynamic performance of passive two-phase cooling devices such as heat pipes and vapor chambers is limited by the capabilities of the capillary wick structures employed. The desired characteristics of wick microstructures are high permeability, high wicking capability and large extended meniscus area that sustains thin-film evaporation. Choices of scale and porosity of wick structures lead to trade-offs between the desired characteristics. In the present work, models are developed to predict the capillary pressure, permeability and thin-film evaporation rates of various micropillared geometries. Novel wicking geometries such as conical and pyramidal pillars on a surface are proposed which provide high permeability, good thermal contact with the substrate and large thin-film evaporation rates. A comparison between three different micropillared geometries – cylindrical, conical and pyramidal – is presented and compared to the performance of conventional sintered particle wicks. The employment of micropillared wick structure leads to a 10-fold enhancement in the maximum heat transport capability of the device. The present work also demonstrates a basis for reverse-engineering wick microstructures that can provide superior performance in phase-change cooling devices. 相似文献
984.
Seven physicochemical parameters (water content, ash, water activity, free, lactone and total acidity, pH and electrical conductivity) were analyzed in 19 nectar honeys of different floral origin and from several regions of Argentina. In addition, the pattern of electrical conductivity and pH upon honey dilution were also studied with increasing honey concentration, the pH values decreased exponentially. The dependence of specific electrical conductivity (κ) on honey concentration was characterized by a maximum at a κ value (κmax) corresponding to a dry solids of honey concentration of 30–35% (w/w). For a given geographical region, ash and acidity values were useful for discriminating honeys of different floral origins. The most adequate parameters for discriminating honeys of different geographical origin were those which described the patterns of pH and electrical conductivity with changes of honey concentration. 相似文献
985.
986.
J Nacher C Ramírez JJ Palop A Molowny JA Luis de la Iglesia C López-García 《Canadian Metallurgical Quarterly》1999,14(1):89-101
By challenging the efficiency of some of our most useful antimicrobial weapons, bacterial antibiotic resistance is becoming an increasingly worrying clinical problem. A good antibiotic is expected to exhibit a high affinity for its target and to reach it rapidly, while escaping chemical modification by inactivating enzymes and elimination by efflux mechanisms. A study of the behaviour of a beta-lactamase-overproducing mutant of Enterobacter cloacae in the presence of several penicillins and cephalosporins showed that the minimum inhibitory concentration (MIC) values for several compounds were practically independent of the sensitivity of the target penicillin binding protein (PBP), even for poor beta-lactamase substrates. This apparent paradox was explained by analysing the equation that relates the antibiotic concentration in the periplasm to that in the external medium. Indeed, under conditions that are encountered frequently in clinical isolates, the factor characterizing the PBP sensitivity became negligible. The conclusions can be extended to all antibiotics that are sensitive to enzymatic inactivation and efflux mechanisms and must overcome permeability barriers. It would be a grave mistake to neglect these considerations in the design of future antibacterial chemotherapeutic agents. 相似文献
987.
Eva Jimnez-Mora Beatriz Gallego Sergio Díaz-Gago Marina Lasa Pablo Baquero Antonio Chiloeches 《International journal of molecular sciences》2021,22(11)
The dysregulation of autophagy is important in the development of many cancers, including thyroid cancer, where V600EBRAF is a main oncogene. Here, we analyse the effect of V600EBRAF inhibition on autophagy, the mechanisms involved in this regulation and the role of autophagy in cell survival of thyroid cancer cells. We reveal that the inhibition of V600EBRAF activity with its specific inhibitor PLX4720 or the depletion of its expression by siRNA induces autophagy in thyroid tumour cells. We show that V600EBRAF downregulation increases LKB1-AMPK signalling and decreases mTOR activity through a MEK/ERK-dependent mechanism. Moreover, we demonstrate that PLX4720 activates ULK1 and increases autophagy through the activation of the AMPK-ULK1 pathway, but not by the inhibition of mTOR. In addition, we find that autophagy blockade decreases cell viability and sensitize thyroid cancer cells to V600EBRAF inhibition by PLX4720 treatment. Finally, we generate a thyroid xenograft model to demonstrate that autophagy inhibition synergistically enhances the anti-proliferative and pro-apoptotic effects of V600EBRAF inhibition in vivo. Collectively, we uncover a new role of AMPK in mediating the induction of cytoprotective autophagy by V600EBRAF inhibition. In addition, these data establish a rationale for designing an integrated therapy targeting V600EBRAF and the LKB1-AMPK-ULK1-autophagy axis for the treatment of V600EBRAF-positive thyroid tumours. 相似文献
988.
Significant correlation is established between the observed electrical properties (room temperature value of dark conductivity and its activation energy) of the plasma deposited highly crystallized undoped hydrogenated microcrystalline silicon (μc-Si:H) films with their microstrucural properties (various aspects like fractional composition of constituent grains, morphology, and crystalline orientation). The conductivity shows three distinct trends with increasing film thickness irrespective of the different deposition parameters or conditions, and these three zones are applicable to all the samples, indicating that all the samples fundamentally belong to three different microstructural classes (with distinct microstructural attributes like thickness and features of grains and conglomerates) corroborative with these three zones of electrical behavior. 相似文献
989.
Building Many-Core Processor-to-DRAM Networks with Monolithic CMOS Silicon Photonics 总被引:1,自引:0,他引:1
Batten Christopher Joshi Ajay Orcutt Jason Khilo Anatol Moss Benjamin Holzwarth Charles W. Popovic Milo A. Li Hanqing Smith Henry I. Hoyt Judy L. Kartner Franz X. Ram Rajeev J. Stojanovic Vladimir Asanovic Krste 《Micro, IEEE》2009,29(4):8-21
Silicon photonics is a promising technology for addressing memory bandwidth limitations in future many-core processors. This article first introduces a new monolithic silicon-photonic technology, which uses a standard bulk CMOS process to reduce costs and improve energy efficiency, and then explores the logical and physical implications of leveraging this technology in processor-to-memory networks. 相似文献
990.
B.V. Manoj Kumar J. Ram Kumar Bikramjit Basu 《International Journal of Refractory Metals and Hard Materials》2007,25(5-6):392-399
TiCN–Ni-based cermets are attractive cutting tools because of the combination of high hardness and wear resistance with improved toughness and thermal shock resistance. The present work reports the effect of WC addition (0–15 wt.%) on the machining performance of TiCN–20 wt.% Ni cermets against boiler steel. The cutting force was measured on-line using dynamometer, with respect to varying cutting speed and feed rate, in dry and orthogonal cutting conditions. The principal aim of the present investigation is to evaluate the dominant mechanisms, responsible for material removal on the rake face of cermets, using SEM–EDS. The cutting performance of TiCN–Ni cermet is observed to improve with the addition of WC content upto 10 wt.%. While, the adhesion of tribochemical layer is dominant with limited WC content, the presence of abrasive grooves and pull-outs are observed for TiCN–20Ni cermets containing higher amount of WC (>10 wt.%). 相似文献