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Transverse magnetoresistance peculiarities of thermoelectric Lu-doped Bi_2Te_3 compound due to strong electrical disorder

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Journal of Rare Earths 2019年第3期37卷 292-298页

作者： Oleg Ivanov maxim yaprintsev Elena Danshina Belgorod State University Belgorod State Technological University named after V.G.Shukhov

The n-type thermoelectric Bi_(1.9)Lu_(0.1)Te_3 was prepared by microwave-solvothermal method and spark plasma sintering. The magnetic field and temperature dependences of transverse magneto resistance measured within temperature 2-200 K interval allow finding the peculiarities characteristic for strongly disordered and inhomogeneous semiconductors. The first peculiarity is due to appearance of linear-inmagnetic field contribution to the total magneto resistance reflected in a crossover from quadratic magnetoresistance at low magnetic fields to linear magneto resistance at high magnetic fields. The linear magnetoresistance can result from the Hall resistance picked up from macroscopically distorted current paths due to local variations in stoichiometry of the compound studied. The second peculiarity is that both linear magnetoresistance magnitude and crossover field are functions of carrier mobility which is in agreement with the Parish and Littlewood model developed for disordered and inhomogeneous semiconductors. An increase in the mobility due to a decrease in temperature is accompanied by an increase in the magnetoresistance magnitude and a decrease in the crossover field. Finally, the third peculiarity is related to the remarkable deviation of the total magnetoresistance measured at various temperatures from the Kohler's rule. Presence of strong inhomogeneity and disorder in the Bi_(1.9)Lu_(0.1)Te_3 structure concluded from the magnetoresistance peculiarities can be responsible for the remarkable reduction in the total thermal conductivity of this compound.

关键词： Bismuth telluride Linear positive magnetoresistance Semiconductors Thermoelectric material Carrier mobility Kohler’s rule

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Microstructure and thermoelectric properties of Bi1.9Lu0.1Te3 compound

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Rare Metals 2018年第8期37卷 642-649页

作者： maxim yaprintsev Roman Lyubushkin Oxana Soklakova Oleg Ivanov Joint Research Centre Belgorod State University BelgorodRussian Federation 308015 Voronezh State Technical University VoronezhRussian Federation 394026

Effect of fabrication conditions on microstructure and thermoelectric properties of the Bi1.9Lu0.lTe3 compound was studied. Starting nanopowder with mean nanoparticle size of -37 nm was synthesized by a microwave-solvothermal method. In order to prepare samples with various micro-grained structures, the synthesized nanopowder was compacted by two methods. The first method is cold isostatic pressing with further high- temperature annealing, while the second method is spark plasma sintering at various temperatures of process （653 and 683 K）. It is found that mean grain size is equal to -290,-730 and -1160 nm for cold isostatically pressed and spark plasma sintered at 653 and 683 K samples, respectively. The micro-grained sample with maximum mean grain size shows the best thermoelectric properties. This sample is structurally inhomogeneous and has the lowest thermal conductivity and the specific electrical resistivity. maximum dimensionless figure of merit for this sample is equal to -0.9 for temperature range of 450-500 K.

关键词： Bi1.9Lu0.1Te3 compound Spark plasmasintering Cold isostatic pressing Grain structure Thermoelectric properties

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About Some Aspects of Use of Optical Sensors for Monitoring the Aquatic Environment

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Journal of Environmental & Earth Sciences 2024年第1期6卷 1-10页

作者： Ferdenant Mkrtchyan Vladimiir Soldatov maxim Mkrtchyan Kotelnikov Institute of Radioengineering&Electronics RAS Fryazino BranchVvedensky Sq.1FryazinoMoscow141190Russia

Multi-channel polarization optical technology is increasingly used for prompt monitoring of water systems.Optical devices during the assessment of water quality determine the intensity of light through the studied aquatic environment.Spectrophotometric devices measure the spectrum of weakening of light through the aquatic environment.Spectroellipsometric devices receive spectra in vertical and horizontal polarizations.The presented article develops an adaptive optical hardware and image system for monitoring water bodies.The system is combined.It consists of 2 parts:1)automated spectrophotometer-refractometer,and 2)adaptive spectroellipsometer.The system is equipped with a corresponding algorithmic and software,including algorithms for identifying spectral curves,databases and knowledge of spectral curves algorithms for solving reverse problems.The presented system is original since it differs from modern foreign systems by a new method of spectrophotometric and spectroellipsometric measurements,an original elemental base of polarization optics and a comprehensive mathematical approach to assessing the quality of a water body.There are no rotating polarization elements in the system.Therefore,this makes it possible to increase the signal-to-noise ratio and,as a result,improve measurement stability and simplify multichannel spectrophotometers and spectroellipsometers.The proposed system can be used in various water systems where it is necessary to assess water quality or identify the presence of a certain set of chemical elements.

关键词： Monitoring Aquatic environment Polarization optics Water object Pollutants Spectral images Classification Identification

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Innate IgM antibodies to mannose in patients with gastric cancer

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Cancer Biology & Medicine 2024年第3期21卷 193-197页

作者： maxim Petrovich Nikulin Nadezhda Vladimirovna Shilova Alexander Dmitrievich Lipatnikov Ivan Sokratovich Stilidi Alexandra Vladimirovna Semyanikhina Nikolai Vladimirovich Bovin Nikolai Nikolaevich Tupitsyn Federal State Budgetary Institution"National Medical Research Center for Oncology Named After N.N.Blokhin"of the Ministry of Health of Russia MoscowRussia State Research Center"Institute of Bioorganic Chemistry Named After Academicians M.M.Shemyakin and Yu.A.Ovchinnikov"of the Russian Academy of Sciences MoscowRussia National Medical Research Center for Obstetrics Gynecology and Perinatology Named After Academician VI.Kulakov of the Ministry of Health of Russian FederationMoscowRussia

Gastric cancer(GC) remains one of the most common lethal diseases. Every year, about 1 million people fall ill and almost 800 thousand people die worldwide~1. Surgical treatment has reached its limit. The current advances in immunology and detection of epidermal growth factor molecules(EGFR) in gastric cancer cells allowed to improve the treatment results;however, the metastatic form of this disease is still incurable.

关键词： Gastric cancer gastric

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Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： maxim V.Grigoriev Anna V.Ruseikina maxim S.Molokeev Vladimir A.Chernyshev Aleksandr S.Aleksandrovsky Alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.Velikanov Alexander A.Garmonov Alexey V.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this work.The structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural type.Thus,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural type.The distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based derivative.Furthermore,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and EuCeCuS3.Ab initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also performed.The types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was assessed.The experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated spectrum.The experimental direct band gap of EuCeCuSe3was measured to be 1.36 eV that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+cation.The dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the Vickers hardness for EuCeCuSe3was calculated to be 5.2 GPa.Finally,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

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Nonlinear Rydberg exciton-polaritons in Cu2O microcavities

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Light(Science & Applications) 2024年第4期13卷 619-627页

作者： maxim Makhonin Anthonin Delphan Kok Wee Song Paul Walker Tommi Isoniemi Peter Claronino Konstantinos Orfanakis Sai Kiran Rajendran Hamid Ohadi Julian Heckötter Marc Assmann Manfred Bayer Alexander Tartakovskii Maurice Skolnick Oleksandr Kyriienko Dmitry Krizhanovskii Department of Physics and Astronomy University of SheffieldSheffield S37RHUK. Department of Physics and Astronomy University of ExeterStocker RoadExeter EX44PYUK. SUPA School of Physics and AstronomyUniversity of St AndrewsSt Andrews KY169SSUK. Fakultät Physik TU DortmundAugust-Schmidt-Straße 444227 DortmundGermany

Rydberg excitons(analogues of Rydberg atoms in condensed matter systems)are highly excited bound electron-hole states with large Bohr radii.The interaction between them as well as exciton coupling to light may lead to strong optical nonlinearity,with applications in sensing and quantum information processing.Here,we achieve strong effective photon–photon interactions(Kerr-like optical nonlinearity)via the Rydberg blockade phenomenon and the hybridisation of excitons and photons forming polaritons in a Cu2O-filled microresonator.Under pulsed resonant excitation polariton resonance frequencies are renormalised due to the reduction of the photon-exciton coupling with increasing exciton density.Theoretical analysis shows that the Rydberg blockade plays a major role in the experimentally observed scaling of the polariton nonlinearity coefficient as∝n4.4±1.8 for principal quantum numbers up to n=7.Such high principal quantum numbers studied in a polariton system for the first time are essential for realisation of high Rydberg optical nonlinearities,which paves the way towards quantum optical applications and fundamental studies of strongly correlated photonic(polaritonic)states in a solid state system.

关键词： density. Rydberg polar

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Major liver resections,perioperative issues and posthepatectomy liver failure:A comprehensive update for the anesthesiologist

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World Journal of Critical Care Medicine 2024年第2期13卷 49-71页

作者： Andrea De Gasperi Laura Petrò Ombretta Amici Ilenia Scaffidi Pietro Molinari Caterina Barbaglio Eva Cibelli Beatrice Penzo Elena Roselli Andrea Brunetti maxim Neganov Alessandro Giacomoni Paolo Aseni Elena Guffanti Former Head Anesthesia and Critical Care Service 2Grande Ospedale Metropolitano Niguarda ASST GOM NiguardaMilan 20163Italy AR1 Ospedale Papa Giovanni 23Bergamo 24100Italy Anesthesia and Critical Care Service 2 Grande Ospedale Metropolitano Niguarda AR2ASST GOM NiguardaMilan 20163Italy Anestesia e Terapia Intensiva Generale Istituto Clinico HumanitasRozzano 20089Italy Chirurgia Oncologica Miniinvasiva Grande Ospedale Metropolitano Niguarda ASST GOM NiguardaMilan 20163Italy Dipartimento di Medicina d’Urgenza ed Emergenza Grande Ospedale Metropolitano Niguarda ASST GOM NiguardaMilano 20163MIItaly

Significant advances in surgical techniques and relevant medium-and long-term outcomes over the past two decades have led to a substantial expansion in the indications for major liver resections.To support these outstanding results and to reduce perioperative complications,anesthesiologists must address and master key perioperative issues(preoperative assessment,proactive intraoperative anesthesia strategies,and implementation of the Enhanced Recovery After Surgery approach).Intensive care unit monitoring immediately following liver surgery remains a subject of active and often unresolved debate.Among postoperative complications,posthepatectomy liver failure(PHLF)occurs in different grades of severity(A-C)and frequency(9%-30%),and it is the main cause of 90-d postoperative mortality.PHLF,recently redefined with pragmatic clinical criteria and perioperative scores,can be predicted,prevented,or anticipated.This review highlights:(1)The systemic consequences of surgical manipulations anesthesiologistsmust respond to or prevent,to positively impact PHLF(a proactive approach);and(2)the maximal intensivetreatment of PHLF,including artificial options,mainly based,so far,on Acute Liver Failure treatment(s),to buytime waiting for the recovery of the native liver or,when appropriate and in very selected cases,toward livertransplant.Such a clinical context requires a strong commitment to surgeons,anesthesiologists,and intensivists towork together,for a fruitful collaboration in a mandatory clinical continuum.

关键词： Liver resection Chronic liver disease Preoperative assessment Vascular clamping Intraoperative hemodynamic monitoring Postoperative intensive care unit Posthepatectomy liver failure Artificial liver support

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北京前门

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城市环境设计 2024年第1期147卷 28-33页

作者：浅野浩克潘居豪王耀亮岳超 maxim Hu 天安时间当代艺术中心 CreatAR Images

本项目与北京的地标建筑天安门广场和长安街有5分钟的步行距离。我们对前门东区进行了改造。这里曾经是明清庭院住宅集中的地区。然而，随着大城市人口的爆炸性增长，这些房子开始被彼此陌生的人居住。因此，历史上的四合院变成了贫民...

本项目与北京的地标建筑天安门广场和长安街有5分钟的步行距离。我们对前门东区进行了改造。这里曾经是明清庭院住宅集中的地区。然而，随着大城市人口的爆炸性增长，这些房子开始被彼此陌生的人居住。因此，历史上的四合院变成了贫民窟，甚至被称为“大杂院”，意指其脏乱。我们的目标是通过将整个地方改造成一个包含办公室、住宅、商店、酒店和餐馆等混合功能的城镇景观，使其成为一个开放的社区，从而焕发活力。

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An advanced theoretical approach to study super-multiperiod superlattices:theory vs experiments

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Journal of Semiconductors 2024年第2期45卷 57-66页

作者： Alexander Sergeevich Dashkov Semyon Andreevich Khakhulin Dmitrii Alekseevich Shapran Gennadii Fedorovich Glinskii Nikita Andreevich Kostromin Alexander Leonidovich Vasiliev Sergey Nikolayevich Yakunin Oleg Sergeevich Komkov Evgeniy Viktorovich Pirogov maxim Sergeevich Sobolev Leonid Ivanovich Goray Alexei Dmitrievich Bouravleuv Saint-Petersburg Electrotechnical University"LETI" Saint Petersburg197022Russian Federation Alferov Saint-Petersburg National Research Academic University of the Russian Academy of Sciences Saint Petersburg194021RussiaFne deration Saint Petersburg Polytechnic University of Peter the Great Saint Petersburg195251Russian Federation Shubnikov Institute of Crystallography of Federal Scientific Research Centre“Crystallography and Photonics” Russian Academy of SciencesMoscow119333Russian Federation National Research Center‘Kurchatov Institute’ Moscow123182Russian Federation University associated with IA EAEC Saint Petersburg194044Russian Federation Institute for Analytical Instrumentation Saint Petersburg198095Russian Federation Ioffe Institute Saint Petersburg194021Russian Federation

A new theoretical method to study super-multiperiod superlattices has been developed.The method combines the precision of the 8-band kp-method with the flexibility of the shooting method and the Monte Carlo approach.This method was applied to examine the finest quality samples of super-multiperiod Al_(0.3)Ga_(0.7)As/GaAs superlattices grown by molecular beam epitaxy.The express photoreflectance spectroscopy method was utilized to validate the proposed theoretical method.For the first time,the accurate theoretical analysis of the energy band diagram of super-multiperiod superlattices with experimental verification has been conducted.The proposed approach highly accurately determines transition peak positions and enables the calculation of the energy band diagram,transition energies,relaxation rates,and gain estimation.It has achieved a remarkably low 5%error compared to the commonly used method,which typically results in a 25%error,and allowed to recover the superlattice parameters.The retrieved intrinsic parameters of the samples aligned with XRD data and growth parameters.The proposed method also accurately predicted the escape of the second energy level for quantum well thicknesses less than 5 nm,as was observed in photoreflectance experiments.The new designs of THz light-emitting devices operating at room temperature were suggested by the developed method.

关键词： super-multiperiod superlattice photoreflectance spectroscopy Kane model kp-method energy band diagram light amplifiers

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基于改进Faster-RCNN算法的软包装印刷缺陷检测研究

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北京印刷学院学报 2024年第3期32卷 28-31,44页

作者：马克西姆郭蓉北京印刷学院智能制造实验室北京102600

本文提出了一种改进的Faster-RCNN算法进行缺陷检测,针对软包装漏印的特点,将原来的VGG16网络替换成运算量更小、网络深度更深的残差网络(ResNet-50),可以提取丰富的特征。为了使卷积神经网络自适应注意,在ResNet-50的残差网络中添加了C... 详细信息

本文提出了一种改进的Faster-RCNN算法进行缺陷检测,针对软包装漏印的特点,将原来的VGG16网络替换成运算量更小、网络深度更深的残差网络(ResNet-50),可以提取丰富的特征。为了使卷积神经网络自适应注意,在ResNet-50的残差网络中添加了CBAM自注意力机制模块。对于数据集,对采集的图像通过旋转、平移、亮度调整、加入噪声、Cutout等操作进行数据增强,避免数据样本不均衡,提升模型的鲁棒性。结果显示,改进后的Faster-RCNN模型与未改进的Faster-RCNN模型相比准确率提高了12%,mAP达到92.95%。证明改进后模型的有效性,节省大量人工成本,提高企业生产效率。

关键词： Faster-RCNN 漏印目标检测

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