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101.
Tekin Karadağ Dustin McPhate Pablo S. Ocal Tolulope Oke Sarah Witherspoon 《Journal of Pure and Applied Algebra》2021,225(6):106597
We present techniques for computing Gerstenhaber brackets on Hochschild cohomology of general twisted tensor product algebras. These techniques involve twisted tensor product resolutions and are based on recent results on Gerstenhaber brackets expressed on arbitrary bimodule resolutions. 相似文献
102.
Yonca Alkan Goksu Volkan Kumbaraci Yusuf Yagci 《Journal of polymer science. Part A, Polymer chemistry》2019,57(3):274-280
A modular approach for the synthesis of graft copolymers by the combination of reversible addition–fragmentation chain‐transfer (RAFT) polymerization and photoinduced acylation processes is described. In the two‐step approach, first the copolymers of benzodioxinone containing monomer, namely, 4‐oxo‐2,2‐diphenyl‐4H‐benzo[d][1,3]dioxin‐7‐yl methacrylate (BDMA) and methyl methacrylate (MMA) in different feed ratios were prepared by RAFT polymerization. In the subsequent step, dichloromethane solutions of these copolymers (PMMA‐co‐PBDMA) were irradiated at λ = 300 nm in the presence of independently prepared hydroxyl functional polymers such as poly(ethylene glycol) (MeO‐PEG‐OH) and poly(?‐caprolactone) (PCL‐OH). Side‐chain esterification reaction between photochemically generated ketene groups and hydroxyl functionalities resulted in the formation graft copolymers. The intermediates and final graft copolymers were characterized by 1H NMR, UV, IR, fluorescence, and GPC measurements. The success of the process was also confirmed by a model reaction using pyrene methanol. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 274–280 相似文献
103.
研究了具有三次非线性项的多阶梯梁的振动,讨论了该系统3:1内共振情况,运用多重尺度法,即一种摄动技术,得到该问题的一般近似解,并得到两种模型的振幅和相位调制方程,这些方程组用来确定稳态解及其稳定性,假设外加的强迫频率接近于较低的频率,在研究的数值部分,讨论固有频率中的3:1情况,对两端固支和一端固支另一端简支,观测到的频率位于第一和第二固有频率之间;对两端简支,观测到的频率位于第二和第三固有频率之间,最后,利用数值算法求解3:1内共振,第一模型为两端固支和一端固支另一端简支梁的外激励模型;第二模型为两端简支梁的外激励模型,然后,当外激励第一模型时,研究第一、二模型的振幅,当外激励第二模型时,研究第二、三模型的振幅,对振动的内共振模型,画出强迫响应、阻尼响应和频率响应曲线,同时进行这些曲线的稳定性分析. 相似文献
104.
A system of Pt nanoparticles and poly(ortho‐phenylenediamine) film electrochemically deposited onto a glassy carbon electrode (GCE/PoPD/Pt) was fabricated. Scanning electron microscopy, Fourier‐transform infrared spectroscopy, and atomic force microscopy techniques were used to identify the surface characteristics of the composite electrode. The conductive polymers and Pt nanoparticles together resulted in a synergistic effect, and the new formed surface was highly active against polyphenolic structures. Rosmarinic acid (RA) and protocatechuic acid (PCA) are phenolic compounds found in plants, and they are used in many applications, particularly as pharmaceuticals. The GCE/PoPD/Pt was used for the simultaneous determination of RA and PCA in a pH 2.0 H2SO4 solution for the first time. The RA and PCA concentrations were determined using differential pulse voltammetry (DPV) and chronoamperometry. By the amperometry measurement, for RA and PCA, a linear relation was observed in the concentration ranges of 1–55 μmol L?1 and 1–60 μmol L?1, with detection limits of 0.5 μmol L?1 and 0.6 μmol L?1, respectively. In the simultaneous determination with DPV, the detection limits for both RA and PCA were calculated as 0.7 μmol L?1. The GCE/PoPD/Pt was successfully used for the simultaneous determination of RA and PCA in a real sample, and its accuracy was verified by high‐performance liquid chromatography studies. 相似文献
105.
Applied Biochemistry and Biotechnology - Depending on its purity, feldspar has a wide application in industry. Fungi play an important role in the feldspar purification. A bacterial leaching study... 相似文献
106.
A brief review of the assignment of elementary fermions and bosons to irreducible multiplets in grand unified \(E_{6}\) models is followed by a discussion of different, hierarchical symmetry breaking chains from \(E_{6}\) down to \(SU(3)_{C} \times U(1)_{EM}\). We concentrate here on a model with an intermediate Pati-Salam symmetry for which \((B-L)\) is conserved. In particular, the mass/mixing matrix of electrically neutral fermions (i.e.neutrinos) that would be derived from Yukawa couplings is constructed. The pattern of neutrino masses and some bounds on mixing parameters are discussed. 相似文献
107.
We obtain the static spherically symmetric solutions of a class of gravitational models whose additions to the General Relativity
(GR) action forbid Ricci-flat, in particular, Schwarzschild geometries. These theories are selected to maintain the (first)
derivative order of the Einstein equations in Schwarzschild gauge. Generically, the solutions exhibit both horizons and a
singularity at the origin, except for one model that forbids spherical symmetry altogether. Extensions to arbitrary dimension
with a cosmological constant, Maxwell source and Gauss-Bonnet terms are also considered. 相似文献
108.
Cihan Topcu Fatih Coldur Bulent Caglar K. Volkan Ozdokur Osman Cubuk 《Electroanalysis》2022,34(3):474-484
A novel solid-state electrochemical sensor based on a newly synthesized cross-linked copper(II) doped-copolymer and carbon nanotube material was developed for the direct determination of monohydrogen phosphate ions (HPO42−). The synthesized copolymers were characterized by FTIR, XPS, TG/DTG-DTA and SEM techniques. The sensor had a Nernstian slope:-30.7±0.4 mV/decade, linear concentrations range: 1.0×10−6 - 1.0×10−1 M, detection limit: 6.5×10−7 M, response time: 4 s and life time: 17 weeks. The sensor displayed constant potentials in the pH range 7.0-9.5. The sensor was successfully used as an indicator electrode in potentiometric titration and the direct determination of HPO4 2− in water samples. 相似文献
109.
Duygu Ergunes Volkan Kumbaraci Bekir Karliga Naciye Talinli 《Journal of heterocyclic chemistry》2007,44(6):1493-1495
110.
Journal of Applied Spectroscopy - The solvent effects on C=O stretching vibrational frequency, ν(C=O), of ketoprofen (KETO) were studied experimentally using attenuated total reflection... 相似文献