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71.
论文建立了一个含有非线性能量汇(NES)装置并输运脉动内流的简支输液管道理论模型,研究了NES装置对管道的非线性动力学特性与振动控制的影响.利用Galerkin和龙格库塔法,得到了在含NES和不含NES装置时管道动力学响应的数值结果.研究表明,NES装置能有效地抑制管道振动.通过对比可知,NES对管道系统的稳定性和非线性振动控制有着明显的影响.此外,论文还详细讨论了NES装置相关参数对系统的动力学影响.结果表明,增大NES的弹簧刚度k、阻尼σ和质量比e有利于管道减振,且最佳安装位置在管道中点.此外,增大阻尼σ能缩小失稳激励频率区域,而其他参数的变化对失稳激励频率区域影响较小. 相似文献
72.
Srinivas Chandrasekaran Masaki Tambo Yuta Yamazaki Tatsuro Muramatsu Yusuke Kanda Takuji Hirose Koichi Kodama 《Molecules (Basel, Switzerland)》2023,28(1)
Enantioseparation of 3-hydroxycarboxylic acids via diastereomeric salt formation was demonstrated using 2-amino-1,2-diphenylethanol (ADPE) and cinchonidine as the resolving agents. Racemic 3-hydroxy-4-phenylbutanoic acid (rac-1), 3-hydroxy-4-(4-chlorophenyl)butanoic acid (rac-2), and 3-hydroxy-5-phenylpentanoic acid (rac-3) were efficiently resolved using these resolving agents. Moreover, the successive crystallization of the less-soluble diastereomeric salt of 1 and cinchonidine using EtOH yielded pure (R)-1 · cinchonidine salt in a high yield. The crystal structures of less-soluble diastereomeric salts were elucidated and it was revealed that hydrogen bonding and CH/π interactions play an important role in reinforcing the structure of the less-soluble diastereomeric salts. 相似文献
73.
74.
Sadataka Furui 《Few-Body Systems》2012,52(1-2):171-187
I analyze the lattice simulation data of the Domain Wall Fermion in quaternion basis. As pointed out by Atiyah and Ward, the minimum action solution for SU(2) Yang–Mills fields in Euclidean 4-space correspond, via Penrose twistor transform, to algebraic bundles on the complex projective 3-space. Assuming dominance of correlation between the fermions on the domain walls via exchange of instantons, I extract parameters necessary for defining gauge fields of Atiyah–Ward ansatz. The QCD effective coupling in the infrared and the relation between the number of flavors and the infrared fixed point is investigated. Consequence of this lepton flavor assignment to phenomenology of baryons is also discussed. 相似文献
75.
Sakai K Imakubo T Ichikawa M Taniguchi Y 《Dalton transactions (Cambridge, England : 2003)》2006,(7):881-883
A highly luminescent zinc(II) complex has been prepared using 3-hydroxypicolinamide; it has a six-coordinated octahedral structure with hydroxides as axial ligands in solution. 相似文献
76.
Optical Review - Point ahead angle (PAA) prediction is important in space laser communication, but the existing methods have low accuracy and complicated calculation processes. In this paper, a new... 相似文献
77.
In an aqueous medium, sodium polyvinyl sulfonate)(PVS-Na) initiated radical polymerization of methyl methacrylate (MMA) in the presence of ferric chloride. The presence of water and Fe(III) ion was essential. The polymerization was concluded to take place in the aqueous phase. The effects of the amount of water, MMA, Fe(III) ion, and temperature on the polymerization were studied. The mechanism of the initiation is discussed. 相似文献
78.
Tatsuro Endo Hikaru TakizawaYasunori Imai Yasuko Yanagida Takeshi Hatsuzawa 《Applied Surface Science》2011,257(7):2560-2566
The specific optical characteristics which can be observed from noble metal nanostructured materials such as nanoparticles and nanoislands have wide variety of applications such as biosensors, solar cells, and optical circuit. Because, these noble metal nanostructures induce the increment of light absorption efficiency by the enhancing effect of electrical field from localized surface plasmon resonance (LSPR) excitation. However, the enhancing effects of electrical field from LSPR using simple structured noble metal nanostructures for several applications are not satisfactory. To realize the more effective light absorption efficiency by the enhancing effect of electrical field, quite different noble metal nanostructures have been desired for applying to several applications using LSPR. In this study, to obtain the more effective enhancing effect of electrical field, conditions for LSPR excitation using a gold-capped nanoparticle layer substrate are computationally analyzed using finite-difference time-domain (FDTD) method. From the previous research, LSPR excitation using such gold-capped nanoparticle layer substrates has a great potential for application to high-sensitive label-free monitoring of biomolecular interactions. For understanding of detailed LSPR excitation mechanism, LSPR excitation conditions were investigated by analyzing the electrical field distribution using simulation software and comparing the results obtained with experimental results. As a result of computational analysis, LSPR excitation was found to depend on the particle alignment, interparticle distance, and excitation wavelength. Furthermore, the LSPR optical characteristics obtained from the simulation analysis were consistent with experimentally approximated LSPR optical characteristics. Using this gold-capped nanoparticle layer substrate, LSPR can be excited easily more than conventional noble metal nanoparticle-based LSPR excitation without noble metal nanoparticle synthesis. Hence, this structure is detectable a small change of refractive index such as biomolecular interactions for biosensing applications. 相似文献
79.
Polylactide (PLA)-grafted dextran (Dex-graft-PLA) of various contents of sugar units was synthesized by anionic polymerization of L-lactide (L-LA) using the alkoxide of partially trimethylsilylated dextran (TMSDex) and subsequently removing the trimethylsilyl (TMS) groups. The copolymer showed different solubility from L-LA homopolymer with increasing the content of sugar units. We prepared bovine serum albumin (BSA)-loaded microspheres (MS)s according to a water-in-oil-in-water emulsion-solvent evaporation/extraction method using methylene chloride/DMSO as an organic cosolvent. MSs prepared from Dex-graft-PLA [MS(Dex-graft-PLA)s] exhibited higher loading efficiency of BSA than MSs prepared from PLLA [MS(PLLA)s]. The in vitro release rate of BSA from MS(Dex-graft-PLA) was faster than that from MS(PLLA). BSA released from MS(Dex-graft-PLA) maintained the secondary structure of native BSA to a great extent, compared with BSA released from MS(PLLA). 相似文献
80.
Styrene(St) was polymerized in benzene solution in the presence of l, 3:2, 4:5, 6-trimethylene-D-sorbitol(TCA) by means of photo-irradiation of system at 30°C. It was found that the polymerization was depressed by the addition of TCA and then proceeded through a radical mechanism. The chain-transfer constant of the styryl radical to TCA was estimated to be 0.16. Accordingly, the photopolymerization of St in the presence of TCA is studied kinetically with regard to chain transfer and termination. 相似文献