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171.
172.
Ito VM Batistella CB Maciel MR Maciel Filho R 《Applied biochemistry and biotechnology》2007,137(1-12):885-896
Soybean oil deodorized distillate is a product derived from the refining process and it is rich in high value-added products. The recovery of these unsaponifiable fractions is of great commercial interest, because of the fact that in many cases, the "valuable products" have vitamin activities such as tocopherols (vitamin E), as well as anticarcinogenic properties such as sterols. Molecular distillation has large potential to be used in order to concentrate tocopherols, as it uses very low temperatures owing to the high vacuum and short operating time for separation, and also, it does not use solvents. Then, it can be used to separate and to purify thermosensitive material such as vitamins.In this work, the molecular distillation process was applied for tocopherol concentration, and the response surface methodology was used to optimize free fatty acids (FFA) elimination and tocopherol concentration in the residue and in the distillate streams, both of which are the products of the molecular distiller. The independent variables studied were feed flow rate (F) and evaporator temperature (T) because they are the very important process variables according to previous experience. The experimental range was 4-12 mL/min for F and 130-200 degrees C for T. It can be noted that feed flow rate and evaporator temperature are important operating variables in the FFA elimination. For decreasing the loss of FFA, in the residue stream, the operating range should be changed, increasing the evaporator temperature and decreasing the feed flow rate; D/F ratio increases, increasing evaporator temperature and decreasing feed flow rate. High concentration of tocopherols was obtained in the residue stream at low values of feed flow rate and high evaporator temperature. These results were obtained through experimental results based on experimental design. 相似文献
173.
174.
Yuanhe Huang Mayumi Okada Kenichi Fukui Kazuyoshi Tanaka Hiroo Aoki Tokio Yamabe 《International journal of quantum chemistry》1997,63(2):361-366
Mixing of triply degenerated lowest unoccupied molecular orbitals (LUMO; t1u) and the next LUMO (NLUMO; t1g) of a neutral C60 molecule was estimated when it becomes dianionic (C602−) and trianionic (C603−) species. The electronic structure of the basic C60 was obtained by a semiempirical (INDO type) Hartree-Fock scheme and the mixing of the t1u and t1g MOs by the conventional configuration interaction (CI) method assuming Ih structural symmetry of a C60 for the sake of simplicity. The most favorable electronic states of C602− and C603− are predicted to be triplet and doublet, respectively. Furthermore, in C602−, the energy difference of this triplet state and the first excited singlet state is very close, which agrees well with the experimental observation. © 1997 John Wiley & Sons, Inc. 相似文献
175.
Gabriela de Morais Gouvêa Lima Aline Chiodi Borges Thalita Mayumi Castaldelli Nishime Gabriela de Fatima Santana-Melo Konstantin Georgiev Kostov Marcia Pinto Alves Mayer Cristiane Yumi Koga-Ito 《Molecules (Basel, Switzerland)》2021,26(18)
Due to the limitations of traditional periodontal therapies, and reported cold atmospheric plasma anti-inflammatory/antimicrobial activities, plasma could be an adjuvant therapy to periodontitis. Porphyromonas gingivalis was grown in blood agar. Standardized suspensions were plated on blood agar and plasma-treated for planktonic growth. For biofilm, dual-species Streptococcus gordonii + P. gingivalis biofilm grew for 48 h and then was plasma-treated. XTT assay and CFU counting were performed. Cytotoxicity was accessed immediately or after 24 h. Plasma was applied for 1, 3, 5 or 7 min. In vivo: Thirty C57BI/6 mice were subject to experimental periodontitis for 11 days. Immediately after ligature removal, animals were plasma-treated for 5 min once—Group P1 (n = 10); twice (Day 11 and 13)—Group P2 (n = 10); or not treated—Group S (n = 10). Mice were euthanized on day 15. Histological and microtomography analyses were performed. Significance level was 5%. Halo diameter increased proportionally to time of exposure contrary to CFU/mL counting. Mean/SD of fibroblasts viability did not vary among the groups. Plasma was able to inhibit P. gingivalis in planktonic culture and biofilm in a cell-safe manner. Moreover, plasma treatment in vivo, for 5 min, tends to improve periodontal tissue recovery, proportionally to the number of plasma applications. 相似文献
176.
K. Yokoi Maki Yakushiji Mayumi Hatanaka Koji Kubono Tsutomu Koide 《Analytical and bioanalytical chemistry》1999,365(4):364-367
A high output low-pressure mercury lamp, 400 W L-Hg, was successfully used for the photolytic decomposition of dissolved oganic compounds as the pretreatment for the determination of trace metal ion in aqueous solution by stripping voltammetry. Various amino acids, showing interferences on voltammetric determination of metal ions, can be removed quite easily by intensive UV irradiation at room temperature. Effect of pH, concentration of electrolyte and dissolved oxygen on the efficiency of photolysis are also described. This method uses no additional chemicals such as acids or oxidants and can be carried out in closed clean conditions. 相似文献
177.
178.
Mayumi Chida Satoru Takahashi Ryunosuke Konishi Dr. Takeshi Matsumoto Dr. Akinobu Nakada Dr. Masanori Wakizaka Dr. Wataru Kosaka Prof. Hitoshi Miyasaka Prof. Ho-Chol Chang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16354-16366
The combination of a cobalt-dioxolene core that exhibits valence tautomerism (VT) with pyridine-3,5-dicarboxylic acid functionalized with chains bearing two, four, or six oxyethylene units led to new complexes ConEGEspy (n = 2, 4, and 6). These complexes commonly form violet crystals of the low-spin (ls)-[CoIII(nEGEspy)2(3,6-DTBSQ)(3,6-DTBCat)] (ls-[CoIII], 3,6-DTBSQ = 3,6-di-tert-butyl semiquinonato, 3,6-DTBCat = 3,6-di-tert-butyl catecholato). Interestingly, violet crystals of Co2EGEspy in the ls-[CoIII] transitioned into a green liquid, accompanied by an almost complete VT shift (94 %) to the high-spin (hs)-[CoII(nEGEspy)2(3,6-DTBSQ)2] (hs-[CoII]) upon melting. In contrast, violet crystals of Co4EGEspy and Co6EGEspy in the ls-[CoIII] exhibited partial VT (33 %) and only a 9.3 % VT shift after melting, respectively. These data demonstrate the tunability of the synchronicity of the molecular VT and macroscopic solid-liquid transitions by optimizing the tethered chains, thus establishing a new strategy for coupling bistable molecules with the macroscopic world. 相似文献
179.
Mayumi Hojo Imchit Termwuttipong 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(4):2166-2176
In this paper, we prove a strong convergence theorem of Halpern’s type for 2-generalized hybrid mappings in a Hilbert space. We also deal with strong convergence theorems by hybrid methods for these nonlinear mappings in a Hilbert space. 相似文献
180.
Shigeaki Ueno Shoji Sasao Hsiuming Liu Mayumi Hayashi Toru Shigematsu Yasuko Kaneko 《高压研究》2013,33(3):509-524
ABSTRACTThe effects of high hydrostatic pressure (HHP) on the physicochemical properties of high-β-glucan barley flour were investigated in the present study. Dough samples were made from two types of barley flour with low and high β-glucan content, respectively, and treated with HHP (200–600?MPa) for 10?min. Although the elevation of pasting properties for the samples treated at 600?MPa was reduced to the same extent as that in wheat flour at normal atmospheric pressure, β-glucan content was maintained regardless of the pressure applied. The significant increase in starch damage of the dough samples at 550 and 600?MPa was confirmed by the results of microscopic observation, which revealed that elliptical starch granules were cracked and damaged in samples with low β-glucan at 600?MPa, and in samples with high β-glucan content at 400?MPa or more. X-ray diffraction patterns of the samples treated at 600?MPa indicated the formation of amylose-lipid complexes that were considered to inhibit the elevation of viscosity. 相似文献