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131.
Application of β-Sitosterol + γ-Oryzanol-Structured Organogel as Migration Barrier in Filled Chocolate Products
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![点击此处可从《Journal of the American Oil Chemists](/ch/ext_images/free.gif)
Alexandra Wendt Karin Abraham Christin Wernecke Julia Pfeiffer Eckhard Flöter 《Journal of the American Oil Chemists' Society》2017,94(9):1131-1140
Oil migration in filled pralines is a phenomenon that is highly correlated with the occurrence of chocolate bloom. In this study the potential to suppress or prevent oil migration by incorporation of sterol/sterolster-structured organogels was evaluated. Different quantities, 2.5 or 14% (w/w), of gel with structurant levels of either 10 or 25% (w/w) were studied in a layered model system. The gel was either a part of the nougat or of the chocolate phase, or as a separate layer. Samples were monitored regularly for a period of 24 weeks at storage temperatures of 10, 18 and 28 °C. The amount of migrated oil was determined via DSC analysis of a surface sample. The results indicate that, despite the additional oil brought into the system via the oleogel, the level of oil found in the chocolate layer is reduced through the presence of the gel. In particular, the three-layer system and gelled chocolate appear to be promising routes to either suppress oil migration or improve nutritional profiles by incorporation of liquid oils. 相似文献
132.
Ku-band antenna array feed distribution network with ferroelectric phase shifters on silicon 总被引:2,自引:0,他引:2
This paper presents the design, fabrication, and experimental results of a 1 : 4 monolithic power distribution network for Ku-band array antenna applications. The network integrated on a high-resistivity silicon (HRS) substrate surface stabilized by polysilicon consists of three Wilkinson power dividers, four dc blocking filters, and four coplanar waveguide (CPW)-to-microstrip (MS) transitions. Each output ports are fed with a barium-strontium-titanate phase shifter. It is found that the introduction of the polysilicon layer between the oxide and HRS reduces RF losses significantly, which will enable the monolithic integration of high-power controller modules onto silicon because of the existence of the oxide layer, preventing any degradation of RF performances. The individual components show insertion losses ranging from 0.4 to 2.6 dB at 15 GHz, and the interconnecting CPW lines result in a loss of 0.064 dB/mm. This network was successfully integrated with MS patch antennas monolithically, showing good performance of 32-dB return loss at 14.85 GHz, and 10/spl deg/ beam-steering capability. 相似文献
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134.
This study examines the relationships between care felt and engagement in innovative behaviors at work. We posit that when an individual perceives that coworkers care for him or her (i.e., care felt), this cultivates psychological conditions such as safety, meaningfulness, and availability, which result in a higher level of motivation and by implication engagement in innovative behaviors at work. A sample of 218 employees took part in the assessment of the relationship between the psychological conditions linked to care felt (measured at Time 1) and motivation and engagement in innovative behaviors (measured at Time 2). The results of structural equation modeling (SEM) indicate that care felt is positively linked to psychological conditions. The latter is positively related directly and indirectly (through motivation) to engagement in innovative behaviors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
135.
J.P. Abraham E.M. Sparrow J.C.K. Tong D.W. Bettenhausen 《International Journal of Thermal Sciences》2010,49(2):256-263
A transition model for internal flows which enables the prediction of the change of flow regime from turbulent through intermittent to laminar has been implemented by numerical simulation. This model had previously been demonstrated to be effective for the prediction of the breakdown of an initially laminar internal flow and its subsequent transitions to either intermittent or turbulent states. The model was employed here to study a flow which is decelerated by passing through a conical diffuser. The flow enters the diffuser with a fully developed turbulent velocity profile and exhibits transitions either in the diffuser or in a pipe situated downstream of the diffuser exit. The presence or absence of flow separation affected the onset of laminarization. Proof that laminarization actually occurred is provided by the values of the fully developed friction factors in the pipe downstream of the exit of the diffuser. These friction factors spanned the range from pure laminar flow through intermittent flow to fully turbulent flow. Comparisons were made with established benchmarks for each of these three flow regimes. 相似文献
136.
We have developed waveguides for the mid-IR spectrum using silver halide crystals. Diffused planar waveguides constructed from silver chlorobromide (AgClBr) with different diffusion thicknesses were designed and characterized. The waveguides were based on our changing the refractive index of the guiding layer by a diffusion of Br- ions into crystalline AgCl substrates. The waveguides were analyzed and investigated with a 10.6-microm CO2 laser, and the optically measured thicknesses of the waveguides were found to vary between 65 and 600 microm. The propagation losses were in the range of 4-16 dB/cm, and the maximal entrance angle was 62 degrees. The output beam distribution was measured and was in good correlation with a numerical analysis simulation based on a ray-tracing model, by use of the eikonal equation. 相似文献
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138.
José A. Llenín Terhi K. Pellinen Dulcy M. Abraham 《Canadian Metallurgical Quarterly》2006,20(3):229-236
Research in accelerated pavement testing (APT) facilities has traditionally focused on the pavement performance such as rutting and fatigue cracking, but documentation on construction management and information of the actual pavement construction quality is limited. There are typically four critical factors that need to be considered to achieve the best possible outcome in construction: cost, schedule, construction process, and quality control, and management. With the objective of developing guidelines for planning and executing construction of a small-scale APT facility, this paper presents a case study documenting and evaluating the construction process and construction management efforts of two sensor-instrumented hot mix asphalt pavement test sections built in a small-scale APT facility. The focus of the experiment was to study bottom-up fatigue cracking of the flexible pavement structure. The presented information and lessons learned serve as a template and guide for agencies pursuing this type of research and pavement construction. 相似文献
139.
K. Cooper S.P. Abraham R.S. Unnithan L. Chung S. Courtney 《Journal of Visual Languages and Computing》2006,17(6):551
The Rational Unified Process is a comprehensive process model that is tailorable, provides templates for the software engineering products, and integrates the use of the Unified Modeling Language (UML); it is rapidly becoming a de facto standard for developing software. The process supports the definition of requirements at multiple levels. Currently, the early requirements, or goals, are captured in a textual document called the Vision Document, as the UML does not include a goal modeling diagram. The goals are subsequently refined into software requirements, captured in UML Use Case Diagrams. Given the well documented advantages of visual modeling techniques in requirements engineering, including the efficient communication and understanding of complex information among numerous diverse stakeholders, the need for an enhanced version of the Vision Document template which supports the visual modeling of goals is identified. Here, an Enhanced Vision Document is proposed which integrates two existing visual goal models: AND/OR Graph for functional goals and Softgoal Interdependency Graph for non-functional goals. A specific approach to establishing traceability relationships from the goals to the Use Cases is presented. Tool support has been developed for the Enhanced Vision Document template; the approach is illustrated using an example system called the Quality Assurance Review Assistant Tool. 相似文献
140.
Caveolae are small microdomains of the plasma membrane that are thought to play important roles in signal transduction processes. In this work, we have investigated the association of Rho proteins with caveolae-enriched membrane domains isolated from cultured endothelial cells. Fractionation of ECV304 cells by sucrose gradient density centrifugation in the absence of detergent resulted in the co-sedimentation of a significant proportion of RhoA and Cdc42 with known caveolae marker proteins, including caveolin, but not with other non-caveolae membrane proteins such as the angiotensin-converting enzyme. Immunoprecipitation experiments carried on crude endothelial cell lysates as well as with solubilized caveolae-enriched membrane domains showed the coimmunoprecipitation of caveolin with RhoA but not with Cdc42. Incubation of endothelial cell lysates with a glutathione-S-transferase (GST)-RhoA fusion protein resulted in the specific precipitation of caveolin, while addition of GST-caveolin-1 to the lysates promoted the precipitation of RhoA. Moreover, incubation of bacterially expressed RhoA with GST-caveolin-1 resulted in the precipitation of RhoA, indicating that RhoA directly interacts with caveolin-1. This interaction was found to be nucleotide-independent and was not affected by prior modification of RhoA with the C3 exoenzyme from C. botulinium or with the cytotoxic necrotinizing factor from E. coli. Taken together, these results suggest the association of RhoA with endothelial caveolae-enriched membrane domains, likely through physical interaction with caveolin-1. These findings may provide new insights into the functions played by Rho proteins and caveolae in signal transduction events. 相似文献