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61.
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Utilisation of spontaneous emulsification to fabricate lutein‐loaded nanoemulsion‐based delivery systems: factors influencing particle size and colour 下载免费PDF全文
Jeonghee Surh Eric Andrew Decker David Julian McClements 《International Journal of Food Science & Technology》2017,52(6):1408-1416
Factors influencing the formation and properties of lutein‐loaded nanoemulsions fabricated using spontaneous emulsification (SE) were investigated. Nanoemulsion formation depended on oil type: small droplets (diameter ≈ 200 nm) with a narrow monomodal particle size distribution (polydispersity index ≈ 0.23) could be formed using medium‐chain triglycerides (MCT), but not long‐chain triglycerides. Nanoemulsion formation also depended on surfactant type and concentration, with Tween 80 being the most effective surfactant. Optimisation of lutein‐loaded nanoemulsions formed by SE led to systems with a final composition of 10 wt% oil phase (0.12 wt% lutein + 9.88 wt% MCT), 10 wt% Tween 80, and 80 wt% aqueous phase. The nanoemulsions were stable to droplet aggregation when stored at ambient temperature for up to 1 month; however, some colour fading occurred due to lutein degradation. This study indicated the potential of nanoemulsion‐based delivery system fabricated using a low‐energy method for encapsulation and protection of lutein. 相似文献
63.
Hannan Tahir Carles Bona-Casas Andrew James Narracott Javaid Iqbal Julian Gunn Patricia Lawford Alfons G. Hoekstra 《Journal of the Royal Society Interface》2014,11(94)
Re-establishing a functional endothelium following endovascular treatment is an important factor in arresting neointimal proliferation. In this study, both histology (in vivo) and computational simulations (in silico) are used to evaluate neointimal growth patterns within coronary arteries along the axial direction of the stent. Comparison of the growth configurations in vivo and in silico was undertaken to identify candidate mechanisms for endothelial repair. Stent, lumen and neointimal areas were measured from histological sections obtained from eight right coronary stented porcine arteries. Two re-endothelialization scenarios (endothelial cell (EC) random seeding and EC growth from proximal and distal ends) were implemented in silico to evaluate their influence on the morphology of the simulated lesions. Subject to the assumptions made in the current simulations, comparison between in vivo and in silico results suggests that endothelial growth does not occur from the proximal and distal ends alone, but is more consistent with the assumption of a random seeding process. This may occur either from the patches of endothelium which survive following stent implantation or from attachment of circulating endothelial progenitor cells. 相似文献
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Surfactant Concentration,Antioxidants, and Chelators Influencing Oxidative Stability of Water‐in‐Walnut Oil Emulsions 下载免费PDF全文
Jianhua Yi Wenbin Dong Zhenbao Zhu Ning Liu Yong Ding David Julian McClements Eric Andrew Decker 《Journal of the American Oil Chemists' Society》2015,92(8):1093-1102
Effects of surfactant concentration, antioxidants with different polarities, and chelator type on the oxidative stability of water‐in‐stripped walnut oil (W/O) emulsions stabilized by polyglycerol polyricinoleate (PGPR) were evaluated. The formation of primary oxidation products (lipid hydroperoxides) and secondary oxidation products (hexanal) decreased with increasing PGPR concentrations (0.3–1.0 wt% of emulsions). Excess surfactant might solubilize lipid hydroperoxides out of the oil–water interface, resulting in the decreased lipid oxidation rates in W/O emulsions. At concentrations of 10–1000 μM, the polar Trolox demonstrated concentration‐dependent antioxidant activity according to both hydroperoxide and hexanal formation. The antioxidant efficiency of the non‐polar α‐tocopherol was slightly reduced at the higher range of 500–1000 μM based on hydroperoxide formation. Both ethylenediaminetetraacetic acid (EDTA) and deferoxamine (DFO) at concentrations of 5–100 μM reduced the rates of lipid oxidation at varying degrees, indicating that endogenous transition metals may promote lipid oxidation in W/O emulsions. EDTA was a stronger inhibitor of lipid oxidation than DFO. These results suggest that the oxidative stability of W/O emulsions could be improved by the appropriate choice of surfactant concentration, antioxidants, and chelators. 相似文献
66.
Julian Bolleter 《Landscape Research》2013,38(5):621-642
Landscape Urbanism has been, to date, a theory emerging primarily from the Western world. This paper counters the Western focus by exploring the potential of Landscape Urbanism theory in Dubai. In a previous article published by the author, landscape architecture in Dubai has been identified as diverging from the tenets of the various charters of the International Federation of Landscape Architects (IFLA), having apparently scant regard for pressing ecological, social and cultural design issues. Landscape Urbanism in this paper is discussed with respect to its ability to bolster the practice of landscape architecture in Dubai in relation to these issues. The paper argues that a number of key facets of Landscape Urbanism appear difficult to reconcile with the ecological, social and cultural conditions of Dubai. Further to this, it tends to lack the tools by which landscape urbanists in Dubai could link theory with practice. 相似文献
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Julian Kosacki Dimitri Feys Fatih Dogan 《International Journal of Applied Ceramic Technology》2022,19(4):2029-2035
Due to its rheological properties, positive lead-acid battery paste can be difficult to spread on lead current collectors accurately and efficiently under industry machinery and setting. Sodium polymethacrylate dispersant was studied as an effective positive paste additive that could lower the yield stress of the paste without affecting paste density and battery performance. Under a four-blade vane rheometer setup, stress growth and oscillatory amplitude strain sweep experiments evaluated the rheological properties of positive paste with the addition of varying amounts of sodium polymethacrylate. Further, the electrochemical effects of sodium polymethacrylate were also evaluated in 2V batteries by testing positive active material utilization and cycle life. 相似文献
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Christoph Schmerbauch Jesus Gonzalez‐Julian Robert Röder Carsten Ronning Olivier Guillon 《Journal of the American Ceramic Society》2014,97(6):1728-1735
We report the sintering behavior of nanocrystalline zinc oxide under external AC electric field between 0 and 160 V/cm. In situ acquisition of density by means of laser dilatometry, evaluation of specimen temperature, real‐time measurement of electric field and current help analyze this peculiar behavior. Field strength and blocking electrodes significantly affect densification and microstructure, which was evaluated in the vicinity of the flash event and for the fully sintered material. High current densities flow through the sample at high electric fields, entailing a sudden increment of the temperature estimated to several hundreds of K and an exaggerated grain growth. In contrast, low current density flows through the sample at lower electric fields, which guarantees normal grain growth and highest final density. Macroscopic photoluminescence measurements give insights into the development of the defect structure. Electric fields are expected to enhance defect mobility, explaining the high densification rates observed during the sintering process. 相似文献