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Terahertz high-sensitivity SIS mixer based on Nb–AlN–NbN hybrid superconducting tunnel junctions

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Chinese Physics B 2024年第5期33卷 681-686页

作者：刘博梁刘冬姚明金骏达王争李婧史生才 Artem Chekushkin Michael Fominsky lyudmila Filippenko Valery Koshelets Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China Kotel'nikov Institute of Radio Engineering and Electronics Russian Academy of SciencesMoscow 125009Russia

The terahertz band,a unique segment of the electromagnetic spectrum,is crucial for observing the cold,dark universe and plays a pivotal role in cutting-edge scientific research,including the study of cosmic environments that support life and imaging black ***-sensitivity superconductor–insulator–superconductor(SIS)mixers are essential detectors for terahertz astronomical telescopes and interferometric *** to the commonly used classical Nb/AlO_(x)/Nb superconducting tunnel junction,the Nb/AlN/NbN hybrid superconducting tunnel junction has a higher energy gap voltage and can achieve a higher critical current *** makes it particularly promising for the development of ultra-wideband,high-sensitivity coherent detectors or mixers in various scientific research *** this paper,we present a superconducting SIS mixer based on Nb/AlN/NbN parallel-connected twin junctions(PCTJ),which has a bandwidth extending up to490 GHz–720 *** best achieved double-sideband(DSB)noise temperature(sensitivity)is below three times the quantum noise level.

关键词： SIS mixer terahertz gap voltage critical current density hybrid superconducting tunnel junction

Data-Driven Design of Single-Atom Electrocatalysts with Intrinsic Descriptors for Carbon Dioxide Reduction Reaction

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Transactions of Tianjin University 2024年第5期30卷 459-469页

作者： Xiaoyun Lin Shiyu Zhen Xiaohui Wang lyudmila V.Moskaleva Peng Zhang Zhi-Jian Zhao Jinlong Gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China School of Economics and Management Tianjin University of Technology and EducationTianjin 300222China Department of Chemistry University of the Free StateP.O.Box 339Bloemfontein 9301South Africa Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China National Industry-Education Platform of Energy Storage Tianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207FujianChina

The strategic manipulation of the interaction between a central metal atom and its coordinating environment in single-atom catalysts(SACs)is crucial for catalyzing the CO_(2)reduction reaction(CO_(2)RR).However,it remains a major *** density-functional theory calculations serve as a powerful tool for catalyst screening,their time-consuming nature poses *** paper presents a machine learning(ML)model based on easily accessible intrinsic descriptors to enable rapid,cost-effective,and high-throughput screening of efficient SACs in complex *** ML model comprehensively captures the influences of interactions between 3 and 5d metal centers and 8 C,N-based coordination environments on CO_(2)RR activity and *** reveal the electronic origin of the different activity trends observed in early and late transition metals during coordination with N *** extreme gradient boosting regression model shows optimal performance in predicting binding energy and limiting potential for both HCOOH and CO *** confirm that the product of the electronegativity and the valence electron number of metals,the radius of metals,and the average electronegativity of neighboring coordination atoms are the critical intrinsic factors determining CO_(2)RR *** developed ML models successfully predict several high-performance SACs beyond the existing database,demonstrating their potential applicability to other *** work provides insights into the low-cost and rational design of high-performance SACs.

关键词： Density functional theory Machine learning CO_(2)reduction reaction Electrocatalysts High-throughput screening

Physico−mathematical model of the voltage−current characteristics of light-emitting diodes with quantum wells based on the Sah−Noyce−Shockley recombination mechanism

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Journal of Semiconductors 2024年第8期45卷 25-33页

作者： Fedor I.Manyakhin Dmitry O.Varlamov Vladimir P.Krylov lyudmila O.Morketsova Arkady A.Skvortsov Vladimir K.Nikolaev Dinamics Strength of Machines and Resisance of MaterialsMoscow Polytechnic UniversityRussia Biomedical and Electronic Means and Technologies Vladimir State UniversityRussia Computer-Aided Design and Engineering National University of Science and Technology"MISiS"Russia

Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their *** technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.

关键词： light-emitting diodes with quantum wells voltage−current relation nonideality factor recombination mechanism Sah−Noyce−Shockley model

Impact of doping profiles on the formation of laser-active centers in bismuth-doped GeO_(2)–SiO_(2)glass fibers

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Photonics Research 2024年第2期12卷 260-270页

作者： SERGEY ALYSHEV ALEXANDER VAKHRUSHEV ALEKSANDR KHEGAI ELENA FIRSTOVA KONSTANTIN RIUMKIN MIKHAIL MELKUMOV lyudmila ISKHAKOVA ANDREY UMNIKOV SERGEI FIRSTOV Prokhorov General Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences 603951 Nizhny NovgorodRussia

Multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication *** development of optical amplifiers operating in the O-,E-,S-,and U-telecom bands is an extremely important challenge for the successful implementation of this ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass *** this work,the impact of the doping profiles of both Ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(MCVD)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or Ge atoms is ***,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

A rare case of cardiac and ophthalmic manifestations of meningococcal septicemia

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World Journal of Emergency Medicine 2024年第4期15卷 328-330页

作者： Svetlana Rachina Anastasia Shchendrygina Heshan Radeesha de Silva Svetlana Tarasenko Nadezhda Mukhina Irina Komarova Ludmila Fedina Elena Burmistrova Elvira Martens Sergey Sidorenko Vladimir Gostev Dmitry Polev Alina Saitova lyudmila Kraeva Nikita Goncharov Irina Zvetkova Department of Hospital Therapy I M Sechenov First Moscow State Medical UniversityMoscow 119048Russia Outpatient Clinic#64 Moscow 119048Russia Department of Cardiology City Clinical Hospital n.a.S.S.YudinMoscow 119048Russia Department of Medical Microbiology and Molecular Epidemiology Pediatric Research and Clinical Center for InfectiousDiseasesSaint Petersburg 197022Russia Department of Medical Microbiology North-Western State Medical University Named After I.I.MechnikovSaintPetersburg 191015Russia Department of Epidemiology Saint-Petersburg Pasteur InstituteSaint Petersburg 197101Russia

Acute pericarditis is usually a self-limiting disorder that commonly occurs due to viral etiology or unexplained *** pericarditis(MP)is a remarkably uncommon clinical entity that manifests as a complication during the acute or convalescent phase of meningococcal ***,its occurrence within the context of meningococcal septicemia has also been *** report a rare case of a previously healthy male patient who developed both acute pericarditis and uveitis as a presentation of meningococcal septicemia,with no characteristic skin rashes or meningeal signs.

关键词： acute Acute rare

Genetic factors of reproductive disorders in female

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Reproductive and Developmental Medicine 2024年第3期8卷 186-195页

作者： Inna I.Mordovina Alina K.Chebanu Maksim Y.Donnikov Tatiana A.Sinyukova lyudmila V.Kovalenko Larisa D.Belotserkovtseva Department of Obstetrics Gynecologyand PerinatologyMedical Institute of Surgut State UniversitySurgutRussian Federation Scientific and Educational Center Medical Institute of Surgut State UniversitySurgutRussian Federation Department of Pathophysiology and General Pathology Director of the Medical InstituteSurgut State UniversitySurgutRussian Federation Surgut Regional Clinical Center for Maternity and Childhood Protection SurgutRussian Federation

Successful reproduction in mammals requires gamete development,fertilization,and early embryonic *** in any of these processes can lead to infertility,recurrent miscarriages,and congenital *** clinical recognition of the genetic causes of female reproductive insufficiency using increasingly advanced genetic technologies poses a serious challenge for reproductive medicine in the 21st ***,the current literature on genetic factors involved in reproductive losses was summarized.A literature search was conducted using Web of Science,MEDLINE,and PubMed databases for articles written in English on the genetic causes of women’s reproductive health *** implementation of whole-exome and wholegenome sequencing is expected to identify numerous genetic factors responsible for oocyte *** will aid in increasing the likelihood of successful female reproductive function,improve the outcomes of assisted reproductive technologies,optimize treatment,and facilitate genetic diagnosis of patients.

关键词： Genetics Infertility Reproductive disorders Premature ovarian insufficiency

Selective sorptive removal of Methyl Red from individual and binary component solutions by mesoporous organosilicas of MCM-41 type

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Journal of Environmental Sciences 2021年第1期33卷 59-71页

作者： Nadiia V.Roik lyudmila A.Belyakova Marina O.Dziazko Chuiko Institute of Surface Chemistry of NAS of Ukraine 17 General Naumov Str.Kyiv 03164Ukraine

Organosilicas with chemically immobilized 3-aminopropyl and Methyl Red-containing surface groups were prepared by sol-gel condensation of tetraethyl orthosilicate and(3-aminopropyl)triethoxysilane in the presence of dye as part of the mixed micelles or dyecontaining silane as silica *** hexagonally arranged mesoporous structure of synthesized materials was confirmed by low-temperature nitrogen adsorption-desorption,xray diffraction,and TEM *** composition of MCM-41-type organosilicas was established by FT-IR spectroscopy and chemical analysis of surface *** of Methyl Red by organosilicas was studied from diluted phosphate buffer solutions in dependence of medium p H,duration of contact,and equilibrium concentration of *** was found that effective removal of Methyl Red takes place at p H values within a range of *** curves of Methyl Red sorption on organosilicas were analyzed by the Lagergren,Ho-McKey,and Weber-Morris kinetic *** was found that the pseudo-second-order model fits the kinetics of Methyl Red sorption on all synthesized materials and the intraparticle diffusion is not the only one mechanism controlling the rate of Methyl Red sorptive *** parameters of equilibrium sorption of Methyl Red on organosilicas of MCM-41 type were calculated using Langmuir,Freundlich,Redlich-Peterson,and Brunauer-Emmett-Teller *** of acid dyes with geometry similar or substantially different from Methyl Red on mesoporous silicas was studied from single and binary component mixtures in aqueous solutions with p H 4.8 and *** was found that selective sorption process is highly dependent on the structural characteristics and protolytic state of silica surface as well as acid dye.

关键词： MCM-41 Sol-gel synthesis Methyl Red Chemical modification Selective sorption

Lead Induces Different Responses of Two Subpopulations of Phagocytes in the Holothurian Eupentacta fraudatrix

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Journal of Ocean University of China 2018年第6期17卷 1391-1403页

作者： DOLMATOVA lyudmila S. DOLMATOV Igor Yu. Laboratory of Biochemistry V.I.Il'ichev Pacific Oceanological Institute Far Eastern Branch Russian Academy of Sciences Laboratory of Comparative Cytology National Scientific Center of Marine Biology Far Eastern Branch Russian Academy of Sciences Department of Cell Biology and Genetics Far Eastern Federal University

In view of increasing lead pollution(Pb^(2+)) of coastal waters, the compensatory abilities of holothurians need to be assessed. The goal of the work is to clarify the functional and phenotypical differences between two types of phagocytes(P1 and P2) in Eupentacta fraudatrix exposed to Pb(NO_3)_2. It has been shown that 2 mg L^(-1) lead exposure for 48 h increases the number of P2 phagocytes as compared to P1 cells, does not significantly affect cell viability in both P1 and P2 phagocyte fractions, and significantly enhances chromatin condensation in P2 but not in P1 phagocytes. A lead concentration of 4 mg L^(-1) increases the number of P1 phagocytes compared to that of P2 type, and does not change cell viability and chromatin condensation in P1 phagocytes. In the P2 type, it decreases cell viability and does not influence the level of apoptosis. The protection against lead-induced apoptosis is apparently mediated by the activities of antioxidant enzymes, especially glutathione S-transferase. The differences in labeling cell surface receptors of P1 and P2 phagocytes by plant lectins also indicate the specific phenotypic properties of these cells. The results clarify the potential and GSH-dependent mechanisms of immune adaptation in holothurians that have been shortly exposed to lead at concentrations close to the maximum environmentally relevant level in coastal waters. Additionally, P1 and P2 phagocytes are first shown to have different functions and phenotypes during the response to lead, which indicates the complexity of the phagocytic system in holothurians and contributes to understanding the immunity evolution.

关键词： amoebocytes antioxidant capacity apoptosis cell adaptation lead plant lectin con A DBA PNA SBA

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跳变马尔可夫系统的最大混合相关熵状态估计

电子学报 2021年第11期49卷 2225-2233页

作者：沈忱 MIHAYLOVA lyudmila 浙江工商大学信息与电子工程学院(萨塞克斯人工智能学院) 浙江杭州310018 谢菲尔德大学自动控制与系统工程系谢菲尔德S102TN

依托于多模型框架的跳变马尔可夫系统状态估计的性能通常受限于多模型间的信息融合程度.本文以交互式多模型方法为框架,针对跳变马尔可夫系统提出了一种基于最大混合相关熵的状态估计方法.为了能有效处理模型高阶信息,在混合和融合步骤... 详细信息

依托于多模型框架的跳变马尔可夫系统状态估计的性能通常受限于多模型间的信息融合程度.本文以交互式多模型方法为框架,针对跳变马尔可夫系统提出了一种基于最大混合相关熵的状态估计方法.为了能有效处理模型高阶信息,在混合和融合步骤引入最大混合相关熵测度替代常规的二阶统计矩准则,设计了关于系统状态的代价函数,通过最优化该函数得到状态估计的迭代解.仿真实验详尽展示了所提方法的主要特征,并表明其在高斯和非高斯噪声环境下都具有较好的估计效果.

关键词：混合相关熵状态估计模型不确定