The primary purpose of this investigation is to observe the effect of the pitching motion on the vortical flow structure and bursting of leading-edge vortices over a delta wing under the sideslip angle, β using a dye visualization technique. In the current work, a delta wing with a sweep angle of Λ = 70° was oscillated in upstroke and downstroke direction to be able to discover the influence of pitching motion on the flow characteristics of the delta wing. The values of mean angles of attack were selected as αm = 25° and αm = 35°, and the sideslip angle was altered from β = 0 to 16°. The delta wing oscillated with the various periods of Te = 5 s, 20 s, and 60 s, respectively. Amplitude of motion was adjusted as αo = ± 5°. It is found that the pitching motion of the delta wing under the sideslip angle β varies the location of the vortex bursting and vortical flow structure substantially.
Abstract Block copolymerization of a hydroxy-terminated oligotriacetylcellulose (1) with a hydroxy-terminated oligodihexanoylchitin (2) was carried out using 4,4′-methylenedi(phenyl isocyanate) as a coupling reagent. The product copolymer has a structure 4 consisting of alternating oligotriacetyl-cellulose and oligodihexanoylchitin units. The complete deprotection of 4 was achieved to give a cellulose-chitin block copolymer 5. 相似文献
Aldose reductase (AR, ALR2), the first enzyme of the polyol pathway, is implicated in the pathophysiology of diabetic complications. Aldose reductase inhibitors (ARIs) thus present a promising therapeutic approach to treat a wide array of diabetic complications. Moreover, a therapeutic potential of ARIs in the treatment of chronic inflammation-related pathologies and several genetic metabolic disorders has been recently indicated. Substituted indoles are an interesting group of compounds with a plethora of biological activities. This article reviews a series of indole-based bifunctional aldose reductase inhibitors/antioxidants (ARIs/AOs) developed during recent years. Experimental results obtained in in vitro, ex vivo, and in vivo models of diabetic complications are presented. Structure–activity relationships with respect to carboxymethyl pharmacophore regioisomerization and core scaffold modification are discussed along with the criteria of ‘drug-likeness”. Novel promising structures of putative multifunctional ARIs/AOs are designed. 相似文献
Sugar dihydroozaxole monomers with two free hydroxyl groups undergo acid-catalyzed polymerization to hyperbranched aminopolysaccharides [Eq. (a)]. Their molecular weights were determined by the light-scattering method to be between 2.3×105 and 7.6×105. The degree of branching determined by 1H NMR spectroscopy after reaction with [iPr2Si(Cl)]2O is close to the ideal value. Ts=MeC6H4SO2, CSA=10-camphorsulfonic acid. 相似文献
Weak bases such as 2-aminopyridine, 4-aminopyridine,o-phenylenediamine,p-phenylenediamine and aniline were intercalated into aluminium dihydrogentriphosphate (ADHP) using ultrasonic wave irradiation. The interlayer spacing of ADHP increased from 8.1 Å to 12.4–20.0 Å. From the values of the layer expansions and host/guest ratios, bilayer or monolayer structures were considered. Chemical oxidation of the aniline resulted in the formation of polyaniline in the ADHP layers.Author for correspondence. 相似文献
The inner surfaces of inorganic layered compounds such as aluminium dihydrogen-triphosphate (ADHP) and layered double hydroxide (LDH) were modified by azo compounds. Upon intercalation of 4-phenylazoaniline and 4,4-azodianiline into ADHP, the interlayer spacing increased from 6.4 to 21.5 Å and 20.6 Å, respectively. The intensity of IR peaks due to P-–OH of ADHP and amino groups of guests decreased by the thermal treatment of the intercalates. The interlayer spacings also decreased to 16.9 Å and 16.7 Å, respectively, indicating a dehydration reaction between P–-OH and amino groups. The LDH inner surface was modified by the reaction with trans-p-phenylazobenzoylchloride (PAB-Cl). Upon surface modification, the interlayer spacing increased from 7.6 Å to about 27 Å. The absorption of this surface-modified LDH near 410 nm increased upon irradiation with UV light and decreased upon irradation with visible light, indicating the occurrence of trans–cis isomerization of PAB-Cl between the layers. 相似文献
In this study, the authors report the use of an aliphatic amine and an aromatic aminoalcohol as synergists with various Type
II initiators by using Photo-DSC (Photo-differential scanning calorimetry) technique. The photopolymerization of triacrylate
and diacrylate was performed under nitrogen atmosphere in the presence of an amine or aminoalcohol with type II initiators,
which allowed us to compare the efficiency of the initiating radicals. The oxygen scavenging role of the amine was left out. 相似文献