Effect of non‐extensivity parameter q on the damping rate of dust ion acoustic waves in non‐extensive dusty plasma

Kinetic theory has been applied to study the damping characteristics of dust ion acoustic waves (DIAWs) in a dusty plasma comprising q‐non‐extensive distributed electrons and ions, while the dust particles are considered extensive following the Maxwellian velocity distribution function. It is found that the results of the three‐dimensional velocity distribution function are more accurate compared to the results of the one‐dimensional velocity distribution function. The numerical solution of the dispersion relation is carried out to study the effect of the non‐extensivity parameter q on the dispersion, the damping rate, and the range of the values of the normalized wavenumber ( k λ_D) for which the DIAWs are weakly damped. It is found that the change in the value of the electron non‐extensivity parameter q_e has a minor effect on the dispersion, the damping rate, and the range of the values of the normalized wavenumber ( k λ_D) for which the DIAWs are weakly damped, while on the other hand, ion non‐extensivity parameter q_i has a strong effect on these arguments. The effect of other parameters, such as the ratio of electron to ion number density and ratio of electron to ion temperature, on the damping characteristics of DIAWs is also highlighted.     

同相气泡耦合特性实验研究

设计实验, 利用电火花打火生成气泡来研究两个气泡之间以及两个气泡与自由面的相互作用, 在实验过程中, 精确控制打火电路, 使两个电火花气泡的生成时间间隔控制在67\mus以内, 实现了气泡的同相生成. 大量实验后发现, 两气泡相互作用过程中可能会出现融合、蘑菇状气泡、对射流、射流方向逆转、反向射流等现象, 自由面附近不同安置方式的两同相气泡会出现不同的脉动形式. 通过系列实验提出了气泡之间的无量纲距离、无量纲周期差等参数来描述气泡耦合特性, 为气泡群的相互作用提供实验依据.}      

7Li quasi-free scattering off the α-cluster in 9Be nucleus

Spectra of coincident charged particles from the reactions induced by a 52 MeV ⁷Li beam incident on a beryllium target were measured. Strong contributions of the ⁷Li quasi-free scattering off the α-cluster in ⁹Be nucleus were observed. This observation supports the conclusions from the study of complete fusion of weakly bound light nuclei at low energies that the “fragility” of the nuclei makes their fusion less probable. Received: 1 June 1998     

Transfer, sequential decay, and quasi-free reactions induced by 18-MeV 6He beam on 6Li, 7Li, and 12C

The ⁶He + ^6,7Li and ⁶He + ¹²C scattering and reactions have been studied using an 18-MeV ⁶He beam. Experimental results for the elastic scattering on all three targets are in fair agreement with optical model predictions, using the potentials found in the analysis of the ⁶Li scattering on the same targets and at close beam energies. Several two-body exit channels show clear signatures of a direct reaction mechanism allowing extraction of spectroscopic information. The measured angular distribution for the ⁶He + ⁶Li → α + ⁸Li reaction indicated close similarity between the α + 2n configuration in ⁶He and the α + d configuration in ⁶Li. The obtained results for α-particle pickup from both ⁶Li and ⁷Li give large values of α spectroscopic factors for some ¹⁰Be states, indicating their well-developed α + ⁶He cluster structure. The exotic two-proton pickup reaction (⁶He, ⁸Be) was studied, as well as two-neutron and triton transfer reactions. Quasi-free scattering of ⁶He on deuteron and α particle in ⁶Li was also observed. The sequential decay reactions ⁶He + ⁶Li → ⁶He + α + d, ⁶He + ⁶Li → 2α + t + n, ⁶He + ⁷Li → ⁶He + α + t, and ⁶He + ¹²C → ¹⁰Be + 2α were clearly seen, and α clustering of some states in ^6,7Li, ^8–10Be, and ¹⁴C was thus studied. Several new spectroscopic results obtained for some ¹⁰Be states support the existence of a molecule-like rotational band in ¹⁰Be with a very large moment of inertia. The text was submitted by the authors in English.     

Enantiomeric pairs of copper(II) polypyridyl-alanine complex salts: anticancer studies

The anticancer properties of two previously characterized pairs of optically pure chiral complex salts [Cu(phen)(ala)(H₂O)]X·xH₂O (phen?=?1.10-phenanthroline; X?=?NO₃^?; ala: l-alanine (l-ala) 1 and d-alanine (d-ala) 2; and (X?=?Cl^?; ala: l-ala, 3 and d-ala, 4; x?=?number of lattice water molecules) are reported herein, together with the crystal structure of the d-enantiomer 4. Unlike cisplatin which is ineffective against MCF-7 cancer cells with the absence of caspase-3 protein expression, these two pairs of complex salts were effective against this cell line and they were able to induce an increase in intracellular ROS, loss in mitochondrial membrane potential, cell cycle arrest mainly at SubG1 phase , caspase-9 activation, and caspase-3/caspase-7-independent apoptosis. Screening of 1 on the NCI-60 panel of human cancer cell lines showed that it was effective against most of the cell lines. MTT-NCI modified assay screening was also done on other cancer cell lines, viz. A549, CNE1, and HepG2, and two normal cell lines, viz. MCF-10A and CHANG. The effects of chirality of these Cu(II) compounds, especially the greater selectivity of d-enantiomers over the l-counterparts, on their anticancer properties are also reported herein.     

Comprehensive study towards the desulfonylation/desulfinylation of cis-3-functionalized 3-phenylsulfonyl/sulfinyl-β-lactams to access novel cis-3-monosubstituted-β-lactams

An inclusive study towards the stereospecific synthesis of novel cis-3-monosubstituted-β-lactams from cis-3-functionalized 3-phenylsulfonyl/sulfinyl-β-lactams is described. 3-Sulfinyl-β-lactams 5/5? successfully furnished stereospecific cis-3-monosubstituted-β-lactams 6, however 3-sulfonyl-β-lactams 2 failed to give the desulfurized product 6?. The final stereochemical and structural conformations of novel β-lactams were established by single crystal X-ray crystallographic study (5c). The cis configuration of the β-lactams 5/5? and 6 was assigned in relevance to E and C4-H and C3-H and C4-H respectively.     

Note on “Inverse minimum cost flow problems under the weighted Hamming distance”

Jiang et al. proposed an algorithm to solve the inverse minimum cost flow problems under the bottleneck-type weighted Hamming distance [Y. Jiang, L. Liu, B. Wuc, E. Yao, Inverse minimum cost flow problems under the weighted Hamming distance, European Journal of Operational Research 207 (2010) 50–54]. In this note, it is shown that their proposed algorithm does not solve correctly the inverse problem in the general case due to some incorrect results in that article. Then, a new algorithm is proposed to solve the inverse problem in strongly polynomial time. The algorithm uses the linear search technique and solves a shortest path problem in each iteration.     

Efficient polymers in conjunction with membranes to remove As(V) generated in situ by electrocatalytic oxidation

Electrochemistry and ultrafiltration membrane methods (electro‐oxidation and liquid phase polymer based retention technique LPR, respectively) were coupled to remove As(III) inorganic species from aqueous solutions. Our main objective was to achieve an efficient extraction of arsenic species by associating a polymer‐assisted liquid phase retention procedure, based on the As(V) adsorption properties of cationic water‐soluble polymers, with the electrocatalytic oxidation process of As(III) into its more easily removable analog As(V). The exhaustive oxidation of As(III)–As(V) was readily performed in high yield at iridium oxide film modified carbon felt electrodes in the presence of different water‐soluble poly(quaternary ammonium) salts acting also as supporting electrolyte. The progress of the macro‐scale oxidation of As(III)–As(V) was followed using iridium oxide film modified glassy carbon electrodes. Finally, a study on arsenic retention by LPR‐technique performed on fully oxidized solutions of arsenic, showing that complete (100%) retention of the arsenic could be achieved using a 20:1 polyammonium:As(III) mole ratio. Copyright © 2009 John Wiley & Sons, Ltd.     

Bis(thiophen-2-yl-methylene) Benzene-1, 4-Diamine as Fluorescent Probe for the Detection of Fe3+ in Aqueous Samples

Journal of Fluorescence - A Schiff base bis(thiophen-2-yl-methylene)benzene-1, 4-diamine (L) was synthesized and used for selective and sensitive detection of Fe3+. L exhibited enhanced...     

An Overview of Variational Autoencoders for Source Separation,Finance, and Bio-Signal Applications

Autoencoders are a self-supervised learning system where, during training, the output is an approximation of the input. Typically, autoencoders have three parts: Encoder (which produces a compressed latent space representation of the input data), the Latent Space (which retains the knowledge in the input data with reduced dimensionality but preserves maximum information) and the Decoder (which reconstructs the input data from the compressed latent space). Autoencoders have found wide applications in dimensionality reduction, object detection, image classification, and image denoising applications. Variational Autoencoders (VAEs) can be regarded as enhanced Autoencoders where a Bayesian approach is used to learn the probability distribution of the input data. VAEs have found wide applications in generating data for speech, images, and text. In this paper, we present a general comprehensive overview of variational autoencoders. We discuss problems with the VAEs and present several variants of the VAEs that attempt to provide solutions to the problems. We present applications of variational autoencoders for finance (a new and emerging field of application), speech/audio source separation, and biosignal applications. Experimental results are presented for an example of speech source separation to illustrate the powerful application of variants of VAE: VAE, β-VAE, and ITL-AE. We conclude the paper with a summary, and we identify possible areas of research in improving performance of VAEs in particular and deep generative models in general, of which VAEs and generative adversarial networks (GANs) are examples.