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151.
Eleonora Truzzi Mohamed Aymen Chaouch Gaia Rossi Lorenzo Tagliazucchi Davide Bertelli Stefania Benvenuti 《Molecules (Basel, Switzerland)》2022,27(5)
The main focus of the current research was the characterization of the by-products from the steam distillation of Lavandula angustifolia Mill. (LA) and Lavandula x intermedia Emeric ex Loisel (LI) aerial parts, as they are important sources of bioactive compounds suitable for several applications in the food, cosmetic, and pharmaceutical industries. The oil-exhausted biomasses were extracted and the total polyphenol and flavonoid contents were, respectively, 19.22 ± 4.16 and 1.56 ± 0.21 mg/g for LA extract and 17.06 ± 3.31 and 1.41 ± 0.10 mg/g for LI extract. The qualitative analysis by liquid chromatography-electrospray tandem mass spectrometry (HPLC-ESI-MS) revealed that both the extracts were rich in phenolic acids and glycosylated flavonoids. The extracts exhibited radical scavenging, chelating, reducing activities, and inhibitory capacities on acetylcholinesterase and tyrosinase. The IC50 values against acetylcholinesterase and tyrosinase were, respectively, 5.35 ± 0.47 and 5.26 ± 0.02 mg/mL for LA, and 6.67 ± 0.12 and 6.56 ± 0.16 mg/mL for LI extracts. In conclusion, the oil-exhausted biomasses demonstrated to represent important sources of bioactive compounds, suitable for several applications in the food, cosmetic, and pharmaceutical industries. 相似文献
152.
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154.
This paper presents a new depth image recovery method for RGB-D sensors giving a complete, sharp, and accurate object shape from a noisy boundary depth map. The proposed method uses the image guided Total Generalized Variation (TGV) with the depth confidence. A new directional hole filling method of view synthesis is also investigated to produce natural texture in hole regions whereas reducing blurring effect and preventing distortion. Thus, a high-quality image view can be achieved. Experimental results show that the proposed method yields higher quality recovered depth maps and synthesized image views than other previous methods. 相似文献
155.
运用密度泛函理论方法研究了烷基碳链长度对氯化三烷基铵络合氯化汞的影响,计算结果表明,氯化三烷基铵与氯化汞的络合作用随着氯化三烷基铵中烷基碳链的增长而增强.通过对络合物的键长、Mayer键级和Mulliken电荷分析可知,电子富集在氯化三烷基铵的Cl原子上,并和Hg原子之间形成静电吸引作用.当烷基长度小于3时,烷基的电子效应影响较为明显,增强了原子之间的电子转移,使得络合物更稳定;当氯化三烷基铵烷基碳链长度大于3后,烷基链长对络合物中的电子转移不再有影响,络合物的稳定性受到烷基的几何效应影响更为明显. 相似文献
156.
往复式压缩机作为工业生产的重要设备有着无可替代的价值。是生产生活必不可少的重要器械。作为最常见的一种压缩机,其故障的危害性不容忽视。本文正是从此出发,分析讨论往复式压缩机重要部件与循环系统的故障对压缩机的影响。 相似文献
157.
根据高炉冲渣水的余热特点,提出了一个采用分离式热管换热器的余热回收的方案。文中对余热回收方案中换热设备的结构特点进行了描述。 相似文献
158.
David L. Henann 《Journal of the mechanics and physics of solids》2010,58(11):1947-1962
Recent experiments in the literature show that micro/nano-scale features imprinted in a Pt-based metallic glass, Pt57.5Ni5.3Cu14.7P22.5, using thermoplastic forming at a temperature above its glass transition temperature, may be erased by subsequent annealing at a slightly higher temperature in the supercooled liquid region (Kumar and Schroers, 2008). The mechanism of shape-recovery is believed to be surface tension-driven viscous flow of the metallic glass. We have developed an elastic-viscoplastic constitutive theory for metallic glasses in the supercooled liquid temperature range at low strain rates, and we have used existing experimental data in the literature for Pt57.5Ni5.3Cu14.7P22.5 (Harmon et al., 2007) to estimate the material parameters appearing in our constitutive equations. We have implemented our constitutive model for the bulk response of the glass in a finite element program, and we have also developed a numerical scheme for calculating surface curvatures and incorporating surface tension effects in finite element simulations. By carrying out full three-dimensional finite-element simulations of the shape-recovery experiments of Kumar and Schroers (2008), and using the independently determined material parameters for the bulk glass, we estimate the surface tension of Pt57.5Ni5.3Cu14.7P22.5 at the temperature at which the shape-recovery experiments were conducted. Finally, with the material parameters for the underlying elastic-viscoplastic bulk response as well as a value for the surface tension of the Pt-based metallic glass fixed, we validate our simulation capability by comparing predictions from our numerical simulations of shape-recovery experiments of Berkovich nanoindents, against corresponding recent experimental results of Packard et al. (2009) who reported shape-recovery data of nanoindents on the same Pt-based metallic glass. 相似文献
159.
Point‐to‐Plane Nonhomogeneous Electric‐Field‐Induced Simultaneous Formation of Giant Unilamellar Vesicles (GUVs) and Lipid Tubes
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Chuntao Zhu Ying Zhang Yinan Wang Qingchuan Li Dr. Wei Mu Prof. Dr. Xiaojun Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):2906-2909
It is well‐known that homogeneous electric fields can be used to generate giant unilamellar vesicles (GUVs). Herein we report an interesting phenomenon of formation of GUVs and lipid tubes simultaneously using a nonhomogeneous electric field generated by point‐to‐plane electrodes. The underlying mechanism was analyzed using finite element analysis. The two forces play main roles, that is, the pulling force (F) to drag GUVs into lipid tubes induced by fluid flow, and the critical force (Fc) to prevent GUVs from deforming into lipid tubes induced by electric fields. In the center area underneath the needle electrode, the GUVs were found because F is less than Fc in that region, whereas in the edge area the lipid tubes were obtained because F is larger than Fc. The diffusion coefficient of lipid in the tubes was found to be 4.45 μm2 s?1 using a fluorescence recovery after photobleaching (FRAP) technique. The method demonstrated here is superior to conventional GUV or lipid tube fabrication methods, and has great potential in cell mimic or hollow material fabrication using GUVs and tubes as templates. 相似文献
160.
Hua-xing Chen Xiao-yan Wu Yi-gang Liu Jian-hua Bai Feng Zhao 《Journal of Dispersion Science and Technology》2016,37(4):486-495
A novel hydrophobically modified polyacrylamide p(AM/NaA/OP-10-AC/BOAM) was successfully synthesized via an aqueous micellar copolymerization method from acrylamide (AM), sodium acrylate (NaA), octylphenol polyoxyethylene acrylate (OP-10-AC), and small amounts of N-benzyl-N-octylacrylamide (BOAM), with the aim of investigating the copolymer's rheological behaviors under various conditions such as polymer concentration, shearing, temperature, and salinity. The copolymer was characterized by infrared spectroscopy, scanning electron microscopy, and atomic force microscope. Scanning electron micrographs show large aggregates in solution formed by the association from the hydrophobic groups of the copolymer. Compared with partially hydrolyzed polyacryamide (HPAM), the copolymer shows a much higher thickening capability and a much greater ability to resist shearing, heat, and salts. This good property of the copolymer is attributed to its three-dimensional dimensional network structure. According to the core flooding test, it can be obtained that oil recovery is enhanced about 4.3% by the copolymer flooding contrasted to the HPAM flooding in mid-low permeability cores under conditions of 1500 mg/L of polymers and 45°C. All the results prove that the copolymer has the capability of increasing oil recovery by improving waterflood sweep efficiency in high-salinity reservoirs. 相似文献