Simulation of Extraction from a Capillary-Porous Particle with Bidisperse Structure

A mathematical model of extraction from a capillary-porous particle with bidisperse structure is described. Results of numerical simulations are presented together with the criterial equation for calculating the effective diffusion coefficient, obtained on processing these results. A criterion is established for selecting the optimal oscillation frequency. The criterion is tested on a physical model, with the obtained numerical results qualitatively confirmed.     

Polynomial identities of bicommutative algebras,Lie and Jordan elements

ABSTRACT

An algebra with identities a(bc)?=?b(ac), (ab)c?=?(ac)b is called bicommutative. We construct list of identities satisfied by commutator and anti-commutator products in a free bicommutative algebra. We give criterions for elements of a free bicommutative algebra to be Lie or Jordan.     

Formation of BiFeO<Subscript>3</Subscript> Nanoparticles Using Impinging Jets Microreactor

The influence of the reactants mixing in an impinging jets microreactor of the formation of singlephase nanocrystals of bismuth orthoferrite has been studied. The 30–100 nm amorphous particles are formed under the impinging jets microreactor conditions, which are converted in bismuth orthoferrite with mean crystallite size 17 nm at 420°С.     

An Exact Order of Discrepancy of the Smolyak Grid and Some General Conclusions in the Theory of Numerical Integration

This paper examines the relationship between the degree of uniformity of distribution of grids, including Smolyak grids, with the intention of choosing weights to obtain efficient quadrature formulas.     

硫胺素-三维荧光法测定水中汞离子的研究

汞是一种具有显著积累效应和遗传毒性的重金属元素,对人体健康和生态环境危害极大。我国水环境中汞污染严重,开发快速、高效、经济的汞离子检测方法可以有效推动水环境中汞污染的源头治理。该研究创新性地提出利用硫胺素-三维荧光法来实现水环境中汞离子的检测。研究结果表明,硫胺素与汞离子发生氧化还原反应前后,其荧光峰的位置与数量发生了明显改变,可作为检测水中汞离子的特征性信号。此外,在利用该法检测水中汞离子时,硫胺素的浓度不宜过高,体系应保持碱性环境,反应温度与反应时间可由一级动力学模型来优化,以期降低检测成本,提高检测效率。在指定的检测条件（硫胺素浓度为10 μmol·L-1、pH为9.7、反应时间为120 min、温度为20 ℃）下,汞离子浓度的线性检测范围为4～15 μmol·L-1。硫胺素-三维荧光法与传统的水中汞离子的检测方法相比具有突出优势和良好的实际应用价值,可以有效助力水环境中汞污染的源头监管,极大提升环境执法效率。     

Intensification of heterogeneous catalytic gas-fluid interactions in reactors with a multichannel monolithic catalyst

The review discusses the present-day state of research, industrial experience, and prospects for application of reactors with a multichannel catalyst for gas-fluid catalytic reactions.     

Hydrodynamics and mass exchange in gas-liquid slug flow in microchannels

The present state of hydrodynamics and mass transfer studies in segmented gas-liquid flow in microchannels has been analyzed. It has been shown that such parameters as gas bubble velocity, gas hold-up, relative gas bubble length, pressure drop, mass transfer coefficients from gas bubbles to liquid slugs and to liquid film, as well as mass transfer coefficient from liquid to channel wall can be satisfactorily predicted. Nevertheless, some correlations were obtained under definite conditions and should be summarized. The purpose of further research is to develop reliable methods for calculation of mass transfer coefficients as functions of channel geometry, phase properties, and phase velocities in mini- and microchannels.     

Modern state and perspectives of microtechnique application in chemical industry

A brief review of application of microtechnique, design and technologies of its manufacturing, methods of process intensification, and use for diagnostic purposes is presented. The main physical factors promoting heat- and mass-transfer intensification are described.