Synthesis of 4-Alkynyl-substituted 3,4-Dihydropyrimidin-2(1H)-ones

4-Alkynyl-3,4-dihydropyrimidin-2-(1H)-ones were synthesized by a one-pot reaction of propynals, ethyl acetoacetate, and urea. The yields of acetylenic dihydropyrimidinones depend significantly upon the propynal structure and catalyst type. A comparative study of the catalysts revealed an important advantage of polyphosphate ester in tetrahydrofuran in comparison with hydrochloric acid in methanol or trimethylchlorosilane in dimethylformamide, allowing the preparation of target compounds in good or moderate yields.     

Convergence in law to operator fractional Brownian motion of Riemann-Liouville type

In this paper, we extend the well-studied fractional Brownian motion of Riemann-Liouville type to the multivariate case, and the corresponding processes are called operator fractional Brownian motions of Riemann-Liouville type. We also provide two results on approximation to operator fractional Brownian motions of Riemann-Liouville type. The first approximation is based on a Poisson process, and the second one is based on a sequence of I.I.D. random variables.     

Perfect controlled joint remote state preparation independent of entanglement degree of the quantum channel

We construct a quantum circuit to produce a task-oriented partially entangled state and use it as the quantum channel for controlled joint remote state preparation. Unlike most previous works, where the parameters of the quantum channel are given to the receiver who can accomplish the task only probabilistically by consuming auxiliary resource, operation and measurement, here we give them to the supervisor. Thanks to the knowledge of the task-oriented quantum channel parameters, the supervisor can carry out proper complete projective measurement, which, combined with the feed-forward technique adapted by the preparers, not only much economizes (simplifies) the receiver's resource (operation) but also yields unit total success probability. Notably, such apparent perfection does not depend on the entanglement degree of the shared quantum channel. Our protocol is within the reach of current quantum technologies.     

Design study and heat transfer analysis of a neutron converter target for medical radioisotope production

A worldwide challenge in the near future will be to find a way of producing radioisotopes in sufficient quantity without relying on research reactors. The motivation for this innovative work on targets lies in the accelerator-based production of radioisotopes using a neutron converter target as in the transmutation by adiabatic resonance crossing concept. Thermal analysis of a multi-channel helium cooled device is performed with the computational fluid dynamics code CFX. Different boundary conditions are taken into account in the simulation process and many important parameters such as maximum allowable solid target temperature as well as uniform inlet velocity and outlet pressure changes in the channels are investigated. The results confirm that the cooling configuration works well; hence such a solid target could be operated safely and may be considered for a prototype target.     

Accelerating Effect of Bio-Reduced Graphene Oxide on Decolorization of Acid Red 18 by Shewanella algae

In this study, the effects of bio-reduced graphene oxide (BRGO) on the bio-reduction of Acid Red 18 (AR 18) by Shewanella algae were first investigated, and a possible mechanism of BRGO-mediated AR 18 bio-decolorization was proposed. The prepared BRGO was characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffractometer (XRD), infrared spectroscopy (IR), Raman spectra, and transmission electron microscope (TEM), respectively. Moreover, electrochemical experiment demonstrated that BRGO is of good electrical conductivity. AR 18 bio-decolorization could be enhanced in dose-dependent manner of BRGO. The maximum increase in AR 18 removal efficiency was observed at a dose of 0.075 g L^?1 BRGO. Under the same conditions, BRGO could also improve the decolorization rates of Acid Red 88, Acid Red 27, and Acid Red 73. During decolorization, the formation of BRGO and cells composite was observed, which is beneficial for transferring electrons from cells to BRGO. In addition, BRGO could accelerate the bio-decolorization of AR 18 under saline conditions (2–7 %). These findings indicate that BRGO can accelerate the electrons transfer from cells to azo dyes.     

Unexpected formation of dinaphthoaza-17-crown-5 ether containing γ-aminopiperidine subunit

1. Download : Download high-res image (90KB)
2. Download : Download full-size image