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排序方式: 共有296条查询结果,搜索用时 31 毫秒
101.
102.
103.
Studies on bubble dynamics 总被引:10,自引:0,他引:10
A. Shima 《Shock Waves》1997,7(1):33-42
In order to clarify the behavior of bubbles which is closely related to cavitation phenomena, the research of the dynamics
of bubbles has been intensively conducted and established the research field of bubble dynamics. In this review paper it is
intended to describe briefly studies on bubble dynamics including the history in conjunction with the shock wave dynamics.
Received 17 June 1996 / Accepted 15 August 1996 相似文献
104.
In low-Reynolds-number turbulent flows, the influence of the molecular viscosity is important. The turbulence models which
are applied to those flows should include the low-Reynolds-number effect. In this study, turbulent flow with the molecular
viscosity effect is analyzed theoretically with the aid of a two-scale direct-interaction approximation (TSDIA) and the energy
spectrum and a new low-Reynolds-number-type eddy-viscosity representation are derived. An priori test for the model expression on the basis of the result of direct numerical simulation (DNS) for turbulent Couette flows
is performed.
Received 5 July 2002 and accepted 8 January 2003 Published online 25 March 2003
Communicated by T.B. Gatski 相似文献
105.
Two new prenylated C?-C? compounds, cycloillicinone (1) and 4-allyl-2-methoxy-6-(2-methylbut-3-en-2-yl)phenol (2), were isolated from the twigs of Illicium anisatum, and their structures were determined by 2D-NMR methods. Cycloillicinone (1) is a unique prenylated C?-C? that is appended with an additional geranyl unit. Compound 2 was found to show moderate neurite-outgrowth promoting activity in primary cultured rat cortical neurons at a concentration of 10 μM. 相似文献
106.
Esmael Rostami Abbas Shockravi Hanif Fattahi Davood Heydarian Shima Shahbanzadeh Minaee Shaghayegh Naghdi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):2066-2077
Dinaphthosulfone aza macrocycles were synthesized from the reaction of diamines and dinaphthosulfone diester (1,1′-sulfoxobis-(2-naphthoxy(2-methyl acetate))) in methanol in the presence of catalytic amounts of para toluenesulfonic acid (p-TsOH). Dinaphthosulfone diester (1,1′-sulfoxobis-(2-naphthoxy(2-methyl acetate))) was synthesized from the corresponding dinaphthosulfide diester and hydrogen peroxide in formic acid at room temperature. Dinaphthosulfide diester was prepared from initial dinaphtholsulfide diol (1,1′-thio bis(2-hydroxy naphthalene)) and methylchloroacetate. 1H NMR spectroscopy showed the unusual splittings for these dinaphthosulfone aza macrocycles, and this finding could be proposed as the role of tetrahedral structure of sulfone functional group, hydrogen bonding in the cavity and size of macrocycle. 相似文献
107.
Dr. Takanori Shima Prof. Dr. Zhaomin Hou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(10):3458-3466
A new family of Y4/M2 and Y5/M heterobimetallic rare‐earth‐metal/d‐block‐transition‐metal? polyhydride complexes has been synthesized. The reactions of the tetranuclear yttrium? octahydride complex [{Cp′′Y(μ‐H)2}4(thf)4] (Cp′′=C5Me4H, 1‐C5Me4H ) with one equivalent of Group‐6‐metal? pentahydride complexes [Cp*M(PMe3)H5] (M=Mo, W; Cp*=C5Me5) afforded pentanuclear heterobimetallic Y4/M? polyhydride complexes [{(Cp′′Y)4(μ‐H)7}(μ‐H)4MCp*(PMe3)] (M=Mo ( 2 a ), W ( 2 b )). UV irradiation of compounds 2 a , b in THF gave PMe3‐free complexes [{(Cp′′Y)4(μ‐H)6(thf)2}(μ‐H)5MCp*] (M=Mo ( 3 a ), W ( 3 b )). Compounds 3 a , b reacted with one equivalent of [Cp*M(PMe3)H5] to afford hexanuclear Y4/M2 complexes [{Cp*M(μ‐H)5}{(Cp′′Y)4(μ‐H)5}{(μ‐H)4MCp*(PMe3)}] (M=Mo ( 4 a ), W ( 4 b )). UV irradiation of compounds 4 a , b provided the PMe3‐free complexes [(Cp′′Y)4(μ‐H)4{(μ‐H)5MCp*}2] (M=Mo ( 5 a ), W ( 5 b )). C5Me4Et‐ligated analogue [(Cp′′Y)4(μ‐H)4{(μ‐H)5Mo(C5Me4Et)}2] ( 5 a′ ) was obtained from the reaction of 1‐C5Me4H with [(C5Me4Et)Mo(PMe3)H5]. On the other hand, the reaction of pentanuclear yttrium? decahydride complex [{(C5Me4R)Y(μ‐H)2}5(thf)2] ( 1‐C5Me5 : R=Me; 1‐C5Me4Et : R=Et) with [Cp*M(PMe3)H5] gave the hexanuclear heterobimetallic Y5/M? polyhydride complexes [({(C5Me4R)Y}5(μ‐H)8)(μ‐H)5MCp*] ( 6 a : M=Mo, R=Me; 6 a′ : M=Mo, R=Et; 6 b : M=W, R=Me). Compound 5 a released two molecules of H2 under vacuum to give [(Cp′′Y)4(μ‐H)2{(μ‐H)4MoCp*}2] ( 7 ). In contrast, compound 6 a lost one molecule of H2 under vacuum to yield [{(Cp*Y)5(μ‐H)7}(μ‐H)4MoCp*] ( 8 ). Both compounds 7 and 8 readily reacted with H2 to regenerate compounds 5 a and 6 a , respectively. The structures of compounds 4 a , 5 a′ , 6 a′ , 7 , and 8 were determined by single‐crystal X‐ray diffraction. 相似文献
108.
In the development of nanoparticle-based vaccine adjuvants, the interaction between nanoparticles (NPs) and the cells is a key factor. To control them, we focused on the relationship between the hydrophobicity of the side chains and the cell membrane. In this study, amphiphilic poly(γ-glutamic acid) (γ-PGA), using various types of hydrophobic side chains, was synthesized and used to prepare NPs for evaluating the membrane disruptive activity. When leucine ethyl ester (Leu), methionine ethyl ester (Met), or tryptophan ethyl ester (Trp) was grafted, each polymer formed monodispersed NPs at physiological conditions. Significantly, NPs composed of Leu and Trp showed a membrane disruptive activity at the endosomal environment (pH 5–6.5), while NPs composed of Met did not show. This might be due to the weak hydrophobicity of Met compared to that of Leu and Trp, which demonstrated that the interaction between NPs and cells could be controlled by designing the polymer compositions. 相似文献
109.
Separation of epimeric 24-isopropenylcholesterols () was effectively achieved by reversed-phase HPLC. The C-24 stereochemistry of these epimers was determined on the basis of chemical and spectroscopic evidence. 相似文献
110.
Z2 (target atomic number) oscillation of equilibrium charge states has been observed for 30–110 MeV Si and 70 and 110 MeV Cl ions after the passage through 22 different Z2 foils. This oscillation may be related to the Z2 oscillation of electron capture cross sections into the projectile K vacancy. 相似文献