Hydrodynamic Characterization of the Formation of Alpha-Tocopherol Nanoemulsions in a Microfluidizer

Author(s):  
Amor Monroy-Villagrana ◽  
Liliana Alamilla-Beltrán ◽  
Humberto Hernández-Sánchez ◽  
Gustavo F. Gutiérrez-López
Keyword(s):  
2016 ◽  
Vol 33 (2) ◽  
pp. 119-126 ◽  
Author(s):  
Ivana Arsić

Summary The aim of the study was to obtain St. John’s wort herb extract (drug:extract ratio 1:5), in a traditional way, using different solvents (sunflower, olive and palm oils) with or without antioxidants (0,02% alpha-tocopherol and 0,01% butylhydroxyanisol). Their characterization was done (organoleptic features, relative density, refractive index, acid number) immediately after the preparation, and during the period of 12 months (the samples were stored at room temperature, 22±2°C). The type of oil used for the extraction of St. John’s wort herb has a significant influence on organoleptic and physicochemical characteristics of extracts. Oil extracts had approximately the same values for refractive index and relative density as solvents used for extraction. The acid numbers of extracts were slightly higher compared to the used oils. Using the antioxidants for preparing the St. John’s wort oil liquid herb extracts did not change the acid number of extracts made using sunflower and palm oils, while oil extracts made using olive oil and tocopherol or BHA had lower acid number values. During the period of 12 months, only extracts which were made using three different vegetable oils, with the use of antioxidants, showed satisfactory physicochemical, chemical and microbiological stability (with no significant changes in organoleptic properties, relative density, refractive index, acid number value and microbiological safety), which points to the necessity of using antioxidants in the preparation of St. John’s wort oil herb extracts, using the traditional method.


2020 ◽  
Vol 24 (3 Part A) ◽  
pp. 1777-1784
Author(s):  
Yu Meng ◽  
Tao Yang ◽  
Zanpei Zhang ◽  
Tongqiang Chen ◽  
Wenyang Xu ◽  
...  

Walnut (Juglans regia) is an important economic tree specie, and has unique aroma in its leaf. In order to investigate the bioactive and bioenergy characteristic of compounds in ethanol and benzene extracts from fresh walnut leaf by gas chromatography/mass spectrometry (GC-MS). The results indicated that ethanol and benzene extracst fresh walnut leaf contain abundant alcohols, aromatic hydrocarbons, quinones, phenols, aldehydes, acids, ketones, alkanes, esterscompounds, especially including dl-.alpha.-Tocopherol, juglone, squalene andlupeol, which are important bioactive components. The functional analytic result suggested that compounds from fresh walnut leaf extracts can be developed into raw materials for industries of biofuel, biomedicine, cosmetic, spices and food additive. The ethanol extract of fresh walnut leaf is more rich in biomedicine and food additives components, such as ketones, alkanes, aldehydes, amines, and acides compounds. The benzene extract of fresh walnut leaf is more rich in biofuels, spices, and cosmetic components, such as phenols, aromatic hydrocarbons, olefines and quinones compounds.


Author(s):  
B. L. Soloff ◽  
T. A. Rado

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.


Author(s):  
A.R. Pelton ◽  
A.F. Marshall ◽  
Y.S. Lee

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.


Author(s):  
B. H. Kear ◽  
J. M. Oblak

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


Author(s):  
Simon Thomas

Trends in the technology development of very large scale integrated circuits (VLSI) have been in the direction of higher density of components with smaller dimensions. The scaling down of device dimensions has been not only laterally but also in depth. Such efforts in miniaturization bring with them new developments in materials and processing. Successful implementation of these efforts is, to a large extent, dependent on the proper understanding of the material properties, process technologies and reliability issues, through adequate analytical studies. The analytical instrumentation technology has, fortunately, kept pace with the basic requirements of devices with lateral dimensions in the micron/ submicron range and depths of the order of nonometers. Often, newer analytical techniques have emerged or the more conventional techniques have been adapted to meet the more stringent requirements. As such, a variety of analytical techniques are available today to aid an analyst in the efforts of VLSI process evaluation. Generally such analytical efforts are divided into the characterization of materials, evaluation of processing steps and the analysis of failures.


Author(s):  
R. J. Lauf

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: (a) characterization of as-deposited SiC coatings; (b) thermodynamics and kinetics of chemical reactions between SiC and fission products; (c) irradiation behavior of SiC in the absence of fission products; and (d) combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast neutron fluences typical of HTGR fuel at end-of-life.


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