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21.
Yasuyuki Tada 《Electrical Engineering in Japan》2014,187(1):16-23
This paper proposes a new estimation method to determine arbitrary circuit parameters for the harmonic analysis of a distribution network. Harmonic analysis is important in maintaining electric power quality. An interesting phenomenon, a temporary cut‐down of the harmonic voltage level at dawn, even if demand is slightly increasing at this time, is often observed in actual power systems. This paper proposes to utilize observations of this phenomenon to estimate circuit parameters. In addition, it is claimed that a detailed equivalent circuit is preferable to a conventional simplified equivalent circuit for explaining the phenomenon. This paper also discusses the usefulness of the Harmonic Characteristics Curve, which is proposed in this paper as a new concept, at the secondary winding of the distribution transformer, and the correlation of PQ, the monitored values of the active and reactive power at the secondary winding of distribution transformer. This correlation should determine the equivalent fundamental frequency admittance of the shunt capacitors installed for distribution lines. © 2014 Wiley Periodicals, Inc. Electr Eng Jpn, 187(1): 16–23, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22451 相似文献
22.
R. Gardinal G.D. Calomeni F. Zanferari T.H.A. Vendramini C.S. Takiya H.G. Bertagnon C.F. Batista A.M.M.P. Della Libera F.P. Renno 《Journal of dairy science》2018,101(1):661-674
The objective of this study was to evaluate different durations of whole raw soybean (WS) supplementation (diet rich in n-6 fatty acid) during the prepartum period on cellular immune function of dairy cows in the transition period and early lactation. Thirty-one Holstein cows were used in a completely randomized design and assigned to 4 experimental groups (G) [G90, G60, G30, and G0 (control)] supplemented with a diet containing 12% of WS from 90, 60, 30 and 0 d relative to the calving date, respectively. Cows were dried off 60 d before the expected calving date. After parturition, all cows were fed a diet containing 12% of WS until 84 DIM. Blood samples were collected before the morning feeding (d ?56 ± 2, ?28 ± 2, ?14 ± 2, ?7 ± 2, at the day of partum, 7 ± 2, 14 ± 2, 28 ± 2, and 56 ± 2 relative to parturition). Cell phenotyping and phagocytosis assays were carried out using monoclonal antibodies and flow cytometry technique. Duration of WS supplementation linearly increased the percentage of blood CD3+ cells, as well as increased the percentage of blood CD8+ cells in the postpartum period, notably in G30, whereas the lowest values were observed in G0. Further, the duration of WS supplementation linearly increased the reactive oxygen species median fluorescence intensity of CH138+ cells after phagocytizing Staphylococcus aureus in the postpartum period. Longer periods of WS supplementation linearly increased phagocytosis median fluorescence intensity of CH138+ cells in the prepartum period of cows. Duration of WS supplementation linearly increased the percentage of blood CD14+ cells producing reactive oxygen species when stimulated either by Staph. aureus or Escherichia coli in the postpartum period. In conclusion, longer periods of WS supplementation during late lactation and the dry period (beginning on d 90 of the expected calving date) alter the leukocyte population and improve neutrophil immune response in the postpartum period with no detrimental effects on cow performance. 相似文献
23.
Susumu Fujii Masato Yoshiya Akuto Yumura Yohei Miyauchi Masahiro Tada Hideyuki Yasuda 《Journal of Electronic Materials》2014,43(6):1905-1915
The phonon thermal conductivity of misfit-layered Ca3Co4O9 has been calculated by perturbed molecular dynamics using a classical force field. Detailed numerical analyses reveal that, in spite of its smaller cross-sectional area, the CoO2 layer transports more heat than the thicker rock salt (RS) layer, although its local thermal conduction is more suppressed than in another layered cobaltite, Na x CoO2. The origins of these differences have been elucidated through careful examination of the atomic arrangements in each layer. Since thermal conduction in the RS layer can be reduced without deteriorating electronic properties for which the CoO2 layer is responsible, it is suggested that the RS layer should be modified to further suppress the overall in-plane thermal conductivity. Computational experiments with increasing number of Ca–O planes in the RS layer showed the opposite trend to what can be predicted based on the misfit between two dissimilar layers. Further analyses to reveal the origin of these unexpected results provide yet another strategy to further decrease the thermal conductivity, namely to control the dynamic interference between atoms across the interface between two layers. 相似文献
24.
25.
Metformin Reduces Lipogenesis Markers in Obese Mice Fed a Low-Carbohydrate and High-Fat Diet 下载免费PDF全文
Karla Nayara de Oliveira Santana Deborah Farias Lelis Keila Lopes Mendes Jamille Fernandes Lula Alanna Fernandes Paraíso João Marcus Oliveira Andrade John David Feltenberger Junio Cota Diego Vicente da Costa Alfredo Mauricio Batista de Paula André Luiz Sena Guimarães Sérgio Henrique Sousa Santos 《Lipids》2016,51(12):1375-1384
Lipogenesis is the process by which fatty acids are synthesized. In metabolic syndrome, an insulin resistant state along with high plasma levels of free fatty acids (FFA) and hyperglycemia may contribute to the lipogenic process. The aim of the present study was to investigate the effects of oral administration of metformin on the expression of lipogenic genes and glycemic profile in mice fed with low‐carbohydrate high‐fat diet by evaluating their metabolic profile. SWISS male mice were divided into 4 groups (N = 7) that were fed with standard (ST), standard plus metformin (ST + MET), low‐carbohydrate high‐fat diet (LCHFD) and low‐carbohydrate high‐fat diet plus metformin (LCHFD + MET) (100 mg kg?1 diet) diets respectively. Food intake, body weight and blood parameters, such as glucose tolerance, insulin sensitivity, glucose, HDL‐c, total cholesterol, triglycerides, ASL and ALT levels were assessed. Histological analyses were performed on hematoxylin and eosin‐stained epididymal adipose tissue histological specimens. The expression levels of peroxisome proliferator‐activated receptor (PPARγ), sterol regulatory element‐binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl‐CoA carboxylase (ACC), were assessed by RT‐PCR. This study showed that metformin decreased adipocyte area, body weight and food consumption in obese animals when compared to the standard group. Furthermore, the expression of lipogenic markers in adipose tissue were diminished in obese animals treated with metformin. This data showed that oral administration of metformin improved glucose and lipid metabolic parameters in white adipose tissue by reducing the expression of lipogenesis markers, suggesting an important clinical application of MET in treating obesity‐related diseases in metabolic syndrome. 相似文献
26.
Atsushi Yoshida Sho Ohata Tatsuhiro Mori Ryuji Tada Pavla Dagsson-Waldhauserová 《Aerosol science and technology》2016,50(3):1-4
Copyright © 2016 American Association for Aerosol Research 相似文献
27.
Eclesielter Batista Moreira Jair Arrieta Baldovino Juliana Lundgren Rose Ronaldo Luis dos Santos Izzo 《岩石力学与岩土工程学报(英文版)》2019,11(2)
One of the conventional ways to improve the mechanical behavior of soils is to mix them with cementing agents such as cement, lime and fly ash. Recently, introduction to alternative materials or sub-products that can be adopted to improve the soil strength is of paramount importance. Therefore, the present study aims to investigate the effects of porosity (η), dry unit weight (γd) of molding, cement content (C) and porosity/volumetric cement content ratio (η/Civ) or void/cement ratio on the unconfined compressive strength (qu or UCS) of silty soil–roof tile waste (RT) mixtures. Soil samples are molded into four different dry unit weights (i.e. 13 kN/m3, 13.67 kN/m3, 14.33 kN/m3 and 15 kN/m3) using 3%, 6% and 9% cement and 5%, 15% and 30% RT. The results show that with the addition of cement, the strength of the RT–soil mixtures increases in a linear manner. On the other hand, the addition of RT decreases qu of the samples at a constant percentage of cement, and the decrease in porosity can increase qu. A dosage equation is derived from the experimental data using the porosity/volumetric cement content ratio (η/Civ) where the control variables are the moisture content, crushed tile content, cement content and porosity. 相似文献
28.
This article illustrates two types of organofunctionalized heterogeneous catalysts for variety of organic carbon–carbon bond-forming reactions, summarizing our previous reports and also presenting new data. Organic amines with an alkoxysilane moiety were immobilized on inorganic silica-alumina surfaces (SA-NR2) by simple silane-coupling reactions between the silica-alumina surface (SA) and the alkoxysilane. This SA-NR2 acted as acid–base bifunctional heterogeneous catalysts for carbon–carbon bond-forming reactions, such as cyano-ethoxycarbonylation, Michael reaction of nitriles, and nitro-aldol reaction. These reactions did not occur with either SA or homogeneous amine compounds. In addition, the mixture of SA and homogeneous amine showed low catalytic activity due to undesirable acid–base neutralization reaction. Achiral organic silane-coupling reagents with a variety of functional groups were also immobilized on a SiO2 surface that had been immobilized with chiral bis(oxazoline) (BOX), to which Cu ions were coordinated to make chiral Cu–BOX complexes on the SiO2 surface. The SiO2-supported Cu–BOX complex catalyst functionalized with achiral 3-methacryloxypropyltrimethoxysilane dramatically increased enantioselectivity in the asymmetric Diels–Alder reaction of cyclopentadiene and 3-acryloyl-2-oxazolidinone. The organofunctionalized catalysts showed much better performances for the C–C bond-forming reactions compared to the corresponding homogeneous systems. The heterogeneous catalysts thus obtained were characterized by solid-state 13C and 29Si MAS NMR, FT-IR, UV/vis, XAFS, ESR, XRF, and elemental analysis. 相似文献
29.
Ana A. Rodrigues Nilza A. Batista Vanessa P. Bavaresco Vitor Baranauskas Helder J. Ceragioli Alfredo C. Peterlevitz Arnaldo R. Santos William D. Belangero 《Carbon》2012,50(2):450-459
Polyvinyl alcohol (PVAl) hydrogel, alone and reinforced with two types of carbon nanoparticles, was studied in cultured cells to assess its potential use in treating osteochondral defects. The carbon nanoparticles were produced by hot-filament chemical vapour deposition. The carbon material was characterised with a Renishaw Invia Raman microscope system and the morphological particles were characterised with field emission scanning electron microscopy and high-resolution transmission electron microscopy. Cytotoxicity was evaluated by measuring the Vero fibroblast-type cells’ metabolic activity and studying their morphology. The osteogenic differentiation of mesenchymal stem cells obtained from rat bone marrow was evaluated by alkaline phosphatase (ALP) and alizarin red S (ARS) staining. Cell viability and morphology were assessed with thiazolyl blue tetrazolium bromide and scanning electron microscopy, respectively. The materials did not interfere with the viability, metabolic activity, morphology and spreading of either of the cell types analysed. Nodules of mineralised organic matrix were identified with ARS and ALP, confirming osteogenic differentiation. These results indicated higher concentration of ALP and mineralised matrix for PVAl with carbon nanoparticles. The results of this study indicate the potential use of carbon nanoparticles with PVAl hydrogels as orthopaedic biomaterials to treat osteochondral defects, but further in vivo investigations are still necessary. 相似文献
30.