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91.
    
Lycopene is usually extracted from the by-product of the tomato industry using organic solvents (OS) in combination with a physical technique. An emerging physical technique is high-pressure processing (HPP). This study aims to find a method by applying a green solvent (edible vegetable oils) in an HPP-assisted solid–liquid extraction. Three dosages of tomato by-product (10%, 20%, and 40%, w/v) were tested using OS, sunflower oil (RSO), and extra-virgin olive oil (EVOO). Lycopene recovery increased with the ratio of by-product to oil, particularly when using EVOO. In another stage of the study, consumers evaluated EVOO that contained two doses of tomato by-product (10% and 20%, w/v). Consumers preferred the EVOO from 10% tomato by-product ratio over that with 20%. Additionally, 83.8% of consumers stated that enriched oil could be deemed beneficial for health. The proposed method considers the fundamental principles of the circular economy and practical industrial scenario to recover lycopene from tomato by-product.  相似文献   
92.
    
The purpose of the work is to study by experimental analysis and finite element methods the mechanical response of a packaging, consisting of a corrugated cardboard container, used for the transport of fruit and vegetables. During the container design, three different configurations were selected which differ both in the choice of liner and in the type of wave. In particular, the type E, F and N microwaves were chosen. They are characterized by a lower amplitude than the high and medium waves commonly used in corrugated cardboard packaging, making it possible to reduce material consumption and, consequently, costs. In the initial phase of the study, experimental tests were performed to evaluate the mechanical strength of the liners. In addition, edge compression tests (ECTs) were performed to determine the stacking resistance of the structure. The break-in resistance of the structures was analysed using a test conducted according to an internal standard, called strength packaging test (SPT). Subsequently, a parametric study was set up with the finite element method for the simulation of the mechanical behaviour of the three structures, using the homogenization technique. The comparison between the maximum total deformations, measured experimentally and calculated numerically, has highlighted the need to introduce corrective coefficients to improve the homogenization of the wave structure. In this way, it was possible to improve the matching of the results obtained on the structures simulated by the homogenization technique and those obtained on the corresponding real structures.  相似文献   
93.
94.
    
We show that under suitable hypotheses on the nonporous material law and a geometric regularity condition on the pore space, Moulinec-Suquet's basic solution scheme converges linearly. We also discuss for which derived solvers a (super)linear convergence behavior may be obtained, and for which such results do not hold, in general. The key technical argument relies on a specific subspace on which the homogenization problem is nondegenerate, and which is preserved by iterations of the basic scheme. Our line of argument is based in the nondiscretized setting, and we draw conclusions on the convergence behavior for discretized solution schemes in FFT-based computational homogenization. Also, we see how the geometry of the pores' interface enters the convergence estimates. We provide computational experiments underlining our claims.  相似文献   
95.
    
ABSTRACT

The high-pressure sliding (HPS) process was applied for grain refinement of a pipe form of an Al-3wt%Mg-0.2wt%Sc alloy by developing two types of straining techniques (called in this study anvil sliding and mandrel sliding). To achieve a homogeneous microstructure throughout the cross-section of the pipe, the sample is rotated around the longitudinal axis every after sliding operation by introducing multi-pass technique, named multi-pass HPS (MP-HPS) as developed earlier for rods. The MP-HPS-processed sample shows ultrafine-grained structures with an average grain size of ~260 and ~300?nm after the HPS processing using anvil sliding and mandrel sliding. The samples also exhibit superplasticity with total elongations well more than 400%, respectively. A finite-element method is used to simulate the evolution of strain in the HPS processing and demonstrates that the simulation well represents the experimental results.  相似文献   
96.
    
Single-, two-, and three-stage homogenization treatments of heat-resistant alloy 2618 were conducted in this study. Results reveal a low melting point Al2CuMg phase and high melting point Al2Cu phase in the as-cast aluminum alloy 2618. After single-stage homogenization at 495 °C for 10 h, the Al2CuMg phase dissolves completely, but the Al2Cu phase cannot be completely dissolved even once the homogenization time is prolonged to 18 h. After the alloy 2618 are homogenized using two stages: 495 °C for 10 h and 520 °C for 8 h, a portion of the Al2Cu phase remains in the alloy. The Al2Cu phase remains undissolved even after prolonged time. After the two-stage homogenization treatment at 495 °C for 10 h and 540 °C for 5 h, the high melting point Al2Cu phase completely dissolves but overburn occurs. After the alloy 2618 are homogenized using three stages at 495 °C for 10 h, 520 °C for 5 h, and 540 °C for 3 h, the Al2Cu phase completely dissolves and no overburn is detected. The three-stage homogenization treatment is an effective method for dissolving the high melting point Al2Cu phase in the alloy 2618 and increasing their overburn temperature and solid solution temperature.  相似文献   
97.
    
Many active materials used in shape-morphing respond to an external stimulus by stretching or contracting along a director field. The programming of such actuators remains complex because of the single degree of freedom (the orientation) in local actuation. Here, texturing this field in zigzag patterns is shown to provide an extended family of biaxial active stretches out of an otherwise single uniaxial active deformation, opening a larger parameter space. By further modulating the zigzag patterns at the larger scale of the structure, its deployed shape can be controlled. This notion of texturing over hierarchical length scales follows geometrical principles, and is robust against changes in size and materials. The robustness of the approach is demonstrated by considering three different responsive materials: inextensible flat fabrics, channel-bearing elastomer (respectively, contracting and expanding perpendicularly to the director field when actuated pneumatically), and 3D-printed thermoplastic (composed of extruded filaments that contract when heated). It is shown that large-scale shape-morphing structures can be generated and that their geometry can be controlled with high accuracy.  相似文献   
98.
介绍了高压水射流除锈机的控制流程 ,提出了一种利用软起动器来实现高压水泵的软起动控制方案 ,分析了软起动器应用的必要性 ,阐述了软起动器的选型及其外围控制 ,并简要介绍了软起动器的开通调试  相似文献   
99.
This paper describes a benchmark model proposed for the clarification of the characteristic of various methods for modeling the laminated iron core. In order to obtain a reference solution of the benchmark model, a large‐scale nonlinear magnetostatic field analysis with a mesh fine enough to represent the microscopic structure of the laminated iron core is carried out by using the hybrid finite element–boundary element (FE‐BE) method combined with the fast multipole method (FMM) based on diagonal forms for translation operators. The computational costs and accuracy of two kinds of homogenization methods are discussed, comparing them with the reference solution. As a consequence, it is verified that the homogenization methods can analyze magnetic fields in laminated iron core within acceptable computational costs. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(1): 26–35, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20809  相似文献   
100.
杨峻  贾楠  曹钜  张劼 《青海电力》2011,(Z2):33-35
高压电能计量装置综合误差主要是通过投运前或定期对电能计量装置各部分在现场或实验室依据规程检测得到的数据进行统计,而对投运后高压电能计量装置在实际运行负荷下的综合误差却难以获得,针对这一难题,文章提出一种在线实时统计高压计量装置综合误差的新方法。  相似文献   
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