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91.
Nuri Ünal 《Foundations of Physics》1998,28(5):755-762
Barut's classical model of the spinning particle having external dynamical variables x and p and internal dynamical variables
and z is taken into account. The path integrations over holomorphic spinors
and z are discussed. This quantization gives the kernel of the relativistic particles with higher spin as well as the Dirac electron. The Green's function of the spin-n/2 particle is obtained. 相似文献
92.
Rachel R. Ogorzalek Loo Richard Hayes Yanan Yang Frank Hung Prasanna Ramachandran Nuri Kim Robert Gunsalus Joseph A. Loo 《International journal of mass spectrometry》2005,240(3):317
Intact protein masses can be measured directly from immobilized pH gradient (IPG) isoelectric focusing (IEF) gels loaded with mammalian and prokaryotic samples, as demonstrated here with murine macrophage and Methanosarcina acetivorans cell lysates. Mass accuracy and resolution is improved by employing instruments which decouple the desorption event from mass measurement; e.g., quadrupole time-of-flight instruments. MALDI in-source dissociation (ISD) is discussed as a means to pursue top-down sequencing for protein identification. Methods have been developed to enzymatically digest all proteins in an IEF gel simultaneously, leaving the polyacrylamide gel attached to its polyester support. By retaining all gel pieces and their placement relative to one another, sample handling and tracking are minimized, and comparison to 2-D gel images is facilitated. MALDI-MS and MS/MS can then be performed directly from dried, matrix-treated IPG strips following whole-gel trypsin digestion, bottom-up methodology. Side-to-side proteomics, highlighting the link between virtual and classical 2-D gel electrophoresis, is introduced to describe a method whereby intact masses are measured from one side (the IEF gel), while proteins are identified based on analyses performed from the other side (the SDS-PAGE gel). 相似文献
93.
A new fluorescent chemosensor (Bodipy-S) derived from Bodipy and Salophen was developed. After the characterization of all compounds, the behavior of the chemosensor Bodipy-S toward p, d and f block-metal ions was investigated by UV-vis and fluorescence spectroscopy. This chemosensor can selectively detect to Cu (II) in methanol-aqueous solution based on chelation enhanced fluorescence (CHEF) and it almost exhibit to a fluorescence quenching effect with 20-fold. The binding constant of the fluorophore was interpreted by using of the Stern-Volmer method and the complex stoichiometry was defined by using Job’s plot. Moreover, the effect of pH was performed by the fluorescence intensities of Bodipy-S in presence of Cu(II) ions. The chemosensor can be successfully used to the detection of Cu(II) in most areas. 相似文献
94.
Meliha Burcu Gürdere Ali Cemal Emeç Osman Nuri Aslan Yakup Budak Mustafa Ceylan 《合成通讯》2016,46(6):536-545
The triethylamin-mediated addition of 2-aminoethanethiol hydrochloride to chalcone analogs was investigated. This addition, bearing a 2-thienyl group at the 3-position, gave the only addition adduct at room temperature in 3 h, whereas the chalcones bearing the 2-furyl group at the 1-position gave an addition-cyclization product (1, 4-thiazepine) in the same conditions. The effect of the groups to the reaction was investigated by changing the 1- and 3-position groups. The chalcones bearing the 2-thienyl group at the 1-position and the others afforded the mixture of products in different ratio at rt for 0.5–24 h. Moreover, the addition–cyclization products (1,4-thiazepine) were obtained under reflux conditions in 36 h. The structures of the synthesized compounds were elucidated by 1H NMR, 13C NMR, infrared, and elemental analysis. 相似文献
95.
Ultrafast dynamics and anionic active states of the flavin cofactor in cryptochrome and photolyase 总被引:1,自引:0,他引:1
Kao YT Tan C Song SH Oztürk N Li J Wang L Sancar A Zhong D 《Journal of the American Chemical Society》2008,130(24):7695-7701
We report here our systematic studies of the dynamics of four redox states of the flavin cofactor in both photolyases and insect type 1 cryptochromes. With femtosecond resolution, we observed ultrafast photoreduction of oxidized state flavin adenine dinucleotide (FAD) in subpicosecond and of neutral radical semiquinone (FADH(*)) in tens of picoseconds through intraprotein electron transfer mainly with a neighboring conserved tryptophan triad. Such ultrafast dynamics make these forms of flavin unlikely to be the functional states of the photolyase/cryptochrome family. In contrast, we find that upon excitation the anionic semiquinone (FAD(*-)) and hydroquinone (FADH(-)) have longer lifetimes that are compatible with high-efficiency intermolecular electron transfer reactions. In photolyases, the excited active state (FADH(-)*) has a long (nanosecond) lifetime optimal for DNA-repair function. In insect type 1 cryptochromes known to be blue-light photoreceptors the excited active form (FAD(*-)*) has complex deactivation dynamics on the time scale from a few to hundreds of picoseconds, which is believed to occur through conical intersection(s) with a flexible bending motion to modulate the functional channel. These unique properties of anionic flavins suggest a universal mechanism of electron transfer for the initial functional steps of the photolyase/cryptochrome blue-light photoreceptor family. 相似文献
96.
Acikbas Yaser Aksoy Mehmet Aksoy Merve Karaagac Damla Bastug Elif Kursunlu Ahmed Nuri Erdogan Matem Capan Rifat Ozmen Mustafa Ersoz Mustafa 《Journal of inclusion phenomena and macrocyclic chemistry》2021,100(1-2):39-54
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Pillar[n]arene is one of the most favorited supramolecular materials that possess a special chiral structure. The major property of... 相似文献
97.
Müller [3], in the Euclidean plane , introduced the one parameter planar motions and obtained the relation between absolute, relative, sliding velocities (and
accelerations). Also, Müller [11] provided the relation between the velocities (in the sense of Complex) under the one parameter
motions in the Complex plane .
Ergin [7] considering the Lorentzian plane , instead of the Euclidean plane , and introduced the one-parameter planar motion in the Lorentzian plane and also gave the relations between both the velocities
and accelerations.
In analogy with the Complex numbers, a system of hyperbolic numbers can be introduced: . Complex numbers are related to the Euclidean geometry, the hyperbolic system of numbers are related to the pseudo-Euclidean
plane geometry (space-time geometry), [5,15].
In this paper, in analogy with Complex motions as given by Müller [11], one parameter motions in the hyperbolic plane are
defined. Also the relations between absolute, relative, sliding velocities (and accelerations) and pole curves are discussed.
相似文献
98.
表述人体下肢生物动力模型的数值技术、数值结果并将其与文献进行比较.模型显示:当人体下肢小腿受冲击外载荷作用时,在膝关节处所产生的4个主要韧带张力以及膝关节处的咬合接触力,在大腿固定不动(或运动受到约束)的情况下,要远大于大腿未受约束的情形.这与医学常识是吻合的. 相似文献
99.
一个解剖基人体下肢的生物动力模型--第一部分: 模型描述 总被引:5,自引:1,他引:4
建立一个完整的解剖基人体下肢二维(矢状面内)生物动力模型,该模型仿真了人体下肢的生物动力运动,并可用来计算人体下肢在冲击外载荷或肌肉活性力的作用下,下肢的重要承力部位-膝关节处的结构力(包括:膝关节的咬合接触力、膝关节处四个主要韧带张力等)和人体下肢的肌肉群力;同时本模型也可用来计算人体下肢在运动期间,膝关节处的咬合位移以及膝关节和髋关节的屈伸位移等。另外,模型还为研究人工关节、人工韧带和人工肌肉 相似文献
100.
A numerical study is performed to analyze steady laminar forced convection in a channel in which discrete heat sources covered
with porous material are placed on the bottom wall. Hydrodynamic and heat transfer results are reported. The flow in the porous
medium is modeled using the Darcy–Brinkman–Forchheimer model. A computer program based on control volume method with appropriate
averaging for diffusion coefficient is developed to solve the coupling between solid, fluid, and porous region. The effects
of parameters such as Reynolds number, Prandtl number, inertia coefficient, and thermal conductivity ratio are considered.
The results reveal that the porous cover with high thermal conductivity enhances the heat transfer from the solid blocks significantly
and decreases the maximum temperature on the heated solid blocks. The mean Nusselt number increases with increase of Reynolds
number and Prandtl number, and decrease of inertia coefficient. The pressure drop along the channel increases rapidly with
the increase of Reynolds number. 相似文献