Estimation of the delay times of signals on the basis of their shape analysis

Time delays between signals emitted by an unknown source are estimated on the basis of the shape analysis of their fragments detected by spatially separated sensors operated under unknown and different conditions [1]. The estimates minimize the maximal error in the time delay of the detected signals with a guaranteed reliability of the estimate [2, 3]. The signal shape is determined as an invariant of the class of transformations modeling the variety of the signal detection conditions.     

Investigation of the Parameters of Muon-Catalyzed Fusion in Double D/T Mixture at High Temperature and Density

Experiments on the study of the muon catalyzed fusion (μCF) process in a double D/T mixture of hydrogen isotopes in the temperature range 300–800 K at densities 0.3–0.5 LHD are performed at the JINR phasotron. The values of the effective μCF parameters (cycling rate λ _c , neutron yield Y _n , muon losses w) are obtained. Tentative dtμ-molecule formation rates on D₂ and DT molecules (λ _dtμ−d and λ _dtμ−t ) are obtained for different mixture temperatures and densities. The results obtained show that λ _dtμ−t increases with temperature, but its value is smaller than theoretical predictions. This revised version was published online in August 2006 with corrections to the Cover Date.     

Separation of mixtures in connected channels

The stationary modes of thermal convection of a binary mixture in connected channels of finite height were studied experimentally and theoretically. The effects of positive and negative thermal diffusion on the convection were examined. The ranges of parameters corresponding to the modes of soft and rigid initiation of convection were determined. Vertical distributions of the temperature and concentration fields were found for various values of the thermal diffusion parameter. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 1, pp. 68–77, January–February, 2009.     

Structure and electric properties of InTe1-x Sex,In1-x GaxTe, and In1-x Tlx Te solid solutions

The local environment of Ga, Tl, and Se atoms in InTe-based solid solutions have been studied by the method of EXAFS spectroscopy. It is shown that these atoms can be regarded as substitutional impurities occupying the In(1), In (2), and Te positions in the InTe structure. Electric measurements showed that the In_1-x Ga_xTe and InTe_1-x Se_x solid solutions are semiconductors at x > 0.24 and x > 0.15, respectively.     

一类推广的Virasoro-like李代数

构造了一类无限维李代数,它是Virasoro-like李代数的推广.研究了这类李代数的两类自同构,这两类自同构均关于映射的合成构成自同构群,一类同构于对称群S3,另一类同构于Klein交换群.得到了这类李代数一些特殊的自同态、中心.证明了这类李代数不是半单李代数.     

Computer design of electrostatic systems of charge particle optics: Systems with spherical electrodes and a fine-structure grid

Problems in computer-aided design of 3D optical systems for charged particle optics are analyzed. The results of simulation of electron-optical systems of optoelectronic transducers with two cathode packs (spherical cathode-plane fine-structure grid as the accelerating electrode and plane cathode-spherical fine-structure grid) are considered. We note a low technological efficiency of such structures and unsatisfactory quality (as it regards some parameters) of the image being recorded due to spherical electrodes and a fine-structure grid in the cathode pack. Numerical analysis of the effect of adjustment of the design on the quality of the image being recorded is carried out.     

氢化物气相外延生长氮化镓单晶衬底的研究进展

氮化镓(GaN)晶体是制备蓝绿光激光器、射频微波器件以及电力电子等器件的理想衬底材料,在激光显示、5G通讯及智能电网等领域具有广阔的应用前景。目前市场上的氮化镓单晶衬底大部分都是通过氢化物气相外延(Hydride Vapor Phase Epitaxy, HVPE)方法生长制备的,在市场需求的推动下,近年来HVPE生长技术获得了快速的发展。本论文综述了近年来HVPE方法生长GaN单晶衬底的主要进展,主要内容包含HVPE生长GaN材料的基本原理、GaN单晶中的掺杂与光电性能调控、GaN单晶中的缺陷及其演变规律和GaN单晶衬底在器件中的应用。最后对HVPE生长方法的发展趋势进行了展望。     

Atomic-Level Regulation of Cobalt Single-Atom Nanozymes: Engineering High-Efficiency Catalase Mimics

Nanozymes aim to mimic the highly evolved active centers of natural enzymes. Despite progress in nanozyme engineering, their catalytic performance is much less favorable compared with natural enzymes. This study shows that precise control over the atomic configuration of the active centers of Co single-atom nanozymes (SAzymes) enables the rational regulation of their catalase-like performance guided by theorical calculations. The constructed Co-N₃PS SAzyme exhibits an excellent catalase-like activity and kinetics, exceeding the representative controls of Co-based SAzymes with different atomic configurations. Moreover, we developed an ordered structure-oriented coordination design strategy for rationally engineering SAzymes and established a correlation between the structure and enzyme-like performance. This work demonstrates that precise control over the active centers of SAzymes is an efficient strategy to mimic the highly evolved active sites of natural enzymes.