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Defence Technology（防务技术） 2022年第7期18卷 1148-1155页

作者： Anatoly G.Korepin Natalia M.Glushakova David B.Lempert Anatoly I.Kazakov Gennady v.Shilov denis v.korchagin vadim M.volokhov Elena S.Amosova Sergey M.Aldoshin Institute of Problems of Chemical Physics Ac.Semenov Avenue 1Chernogolovka142432Russian Federation

The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in 2020.NBTAT compound crystallizes in the monoclinic system,space group P2(1)/n,density at room temperature 1.939 g/cm^(3).The energies of crystal packing and pairwise intermolecular interactions in NBTAT and its unnitrated analogue BTAT were calculated,and their comparative analysis was carried out.The enthalpy of formation of NBTAT molecules was calculated by quantum-chemical methods using Gaussian 09,and the enthalpy of formation of NBTAT in the solid phase(618 kJ/mol)was estimated.The energy capabilities of NBTAT as an oxidizer of solid composite propellants are estimated.It is shown that in metal-free compositions NBTAT is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HMX,BTAT at all stages of rocket systems,and is comparable to the superdense CL-20 yielding to the latter at the lower stages and slightly winning at the upper stages.

关键词： Nitrogen heterocycles Quantum chemistry Enthalpy of formation 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine Crystal structure Energetic ability

Laser-optimized Pt-Y alloy nanoparticles embedded in Pt-Y oxide matrix for high stability and ORR electrocatalytic activity

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Journal of Energy Chemistry 2024年第5期92卷 508-520页

作者： Riccardo Brandiele Andrea Guadagnini Mattia Parnigotto Federico Pini vito Coviello denis Badocco Paolo Pastore Gian Andrea Rizzi Andrea vittadini Daniel Forrer vincenzo Amendola Christian Durante Department of Chemical Sciences University of PaduaVia Marzolo 135131 PadovaItaly Istituto di Chimica della Materia Condensata e di Tecnologie per l’Energia ICMATE-CNR via Marzolo 1 I-35131 PadovaItaly

The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday technology.While nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating conditions.In this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ORR.Pt_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in liquid.The novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(ve with E_(1/2)=0.943 v vs.RHE,specific activity=1095μA cm^(-2) and mass activity>1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.

关键词： Electrocatalysis GDE ORR Pt_(2)Y Pt_(3)Y LAL LFL Oxide support Pto Nanoalloys

Root structure syndromes of four families of monocots in the Middle Urals

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Plant Diversity 2023年第6期45卷 722-731页

作者： Anna A.Betekhtina Daria E.Tukova denis v.veselkin Ural Federal University Named After the First President of Russia B.N.Yeltsin 19 Mira StreetEkaterinburg 620002Russia Ural Branch of the Russian Academy of Sciences Institute of Plant and Animal Ecology8 Marta StreetEkaterinburg 620144Russia

The present article tests the following general assumption:plant taxa with different specializations towards mycorrhizal interactions should have different root syndromes.Roots of 61 species common in boreal zone were studied:16 species of Poaceae,24 species of Cyperaceae,14 species of Orchidaceae,and 7 species of Iridaceae.Using a fixed material of 5 individuals of each species,the following was determined:number of orders of branching roots;transverse dimensions of root,stele and cortex;number of primary xylem vessels and exodermis layers;length of root hairs;abundance of mycorrhiza.Species of each family had well-defined syndromes.Roots of Orchidaceae and Iridaceae were thick with a large stele and developed exodermis.Orchidaceae had no branching roots and had long root hairs.In Iridaceae,roots were branched,and root hairs were short.Roots of Poaceae and Cyperaceae were thin with a relatively thin stele.Root hairs were short in Poaceae and long in Cyperaceae.Our finding that root syndromes of four families of monocots differed is a new and unexpected discovery.The high specificity of root syndromes in Cyperaceae,Iridaceae,Poaceae,and Orchidaceae indicates that species of these families use different strategies to obtain water and soil nutrients.

关键词： Monocots Poaceae Cyperaceae Orchidaceae Iridaceae Syndromes of roots structure

Development of a methodology for assessing the adequacy of electric power systems

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Global Energy Interconnection 2022年第5期5卷 543-550页

作者： Dmitry S.Krupenev denis A.Boyarkin Dmitrii v.Iakubovskii Melentiev Energy Systems Institute of Siberian Branch of the Russian Academy of Sciences Lermontov str.130Irkutsk664033Russia

This study presents the results of a research into the developing a methodology for assessing the adequacy of advanced electric power systems characterized by the integration of various innovative technologies,which complicates their analysis.The methodology development is aimed at solving two main problems:(1)increase the adequacy of modeling the processes that occur in the electric power system and (2)enhance the computational efficiency of the adequacy assessment methodology.This study proposes a new mathematical model to minimize the power shortage and enhance the adequacy of modeling the processes.The model considers quadratic power transmission losses and network coefficients.The computational efficiency of the adequacy assessment methodology is enhanced using efficient random-number generators to form the calculated states of electric power systems and machine learning methods to assess power shortages and other reliability characteristics in the calculated states.

关键词： Electric power systems Adequacy Power shortage minimization Pseudo-and quasi-random number generation Machine learning methods.

Pitfalls and promises of bile duct alternatives:There is plenty of room in the regenerative surgery

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World Journal of Gastroenterology 2023年第30期29卷 4701-4705页

作者： Ilya D Klabukov denis S Baranovskii Peter v Shegay Andrey D Kaprin Department of Regenerative Medicine National Medical Research Radiological Center of the Ministry of Health of the Russian FederationObninsk 249036Russia Center for Innovative Radiological and Regenerative Technologies National Medical Research Radiological Center of the Ministry of Health of the Russian FederationObninsk 249036Russia

Current abdominal surgery has several approaches for biliary reconstruction.However,the creation of functional and clinically applicable bile duct substitutes still represents an unmet need.In the paper by Miyazawa and colleagues,approaches to the creation of bile duct alternatives were summarized,and the reasons for the lack of development in this area were explained.The history of bile duct surgery since the nineteenth century was also traced,leading to the conclusion that the use of bioabsorbable materials holds promise for the creation of bile duct substitutes in the future.We suggest three ideas that may stimulate progress in the field of bile duct substitute creation.First,a systematic analysis of the causative factors leading to failure or success in the creation of bile duct substitutes may help to develop more effective approaches.Second,the regeneration of a bile duct is delicately balanced between epithelialization and subsequent submucosal maturation within limited time frames,which may be more apparent when using quantitative models to estimate outcomes.Third,the utilization of the organism’s endogenous regeneration abilities may enhance the creation of bile duct substitutes.We are convinced that an interdisciplinary approach,including quantitative methods,machine learning,and deep retrospective analysis of the causes that led to success and failure in studies on the creation of bile duct substitutes,holds great value.Additionally,more attention should be directed towards the balance of epithelialization and submucosal maturation rates,as well as induced angiogenesis.These ideas deserve further investigation to pave the way for bile duct restoration with physiologically relevant outcomes.

关键词： Bile duct alternative Bile duct substitute Regenerative medicine Regene rative surgery Theoretical surgery Quantitative human physiology

Revealing the nature of optical activity in carbon dots produced from different chiral precursor molecules

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Light(Science & Applications) 2022年第5期11卷 855-867页

作者： Ananya Das Evgeny v.Kundelev Anna A.vedernikova Sergei A.Cherevkov denis v.Danilov Aleksandra v.Koroleva Evgeniy v.Zhizhin Anton N.Tsypkin Aleksandr P.Litvin Alexander v.Baranov Anatoly v.Fedorov Elena v.Ushakova Andrey L.Rogach Center of Information Optical Technologies ITMO UniversitySaint Petersburg 197101Russia Research Park Saint Petersburg State UniversitySaint Petersburg 199034Russia Laboratory of Femtosecond Optics and Femtotechnology ITMO UniversitySaint Petersburg 197101Russia Laboratory of Quantum Processes and Measurements ITMO UniversitySaint Petersburg 197101Russia Department of Materials Science and Engineering and Centre for Functional Photonics(CFP)City University of Hong KongKowloonHong Kong SAR 999077China Shenzhen Research Institute City University of Hong KongShenzhen 518057China

Carbon dots(CDs)are light-emitting nanoparticles that show great promise for applications in biology and medicine due to the ease of fabrication,biocompatibility,and attractive optical properties.Optical chirality,on the other hand,is an intrinsic feature inherent in many objects in nature,and it can play an important role in the formation of artificial complexes based on CDs that are implemented for enantiomer recognition,site-specific bonding,etc.We employed a one-step hydrothermal synthesis to produce chiral CDs from the commonly used precursors citric acid and ethylenediamine together with a set of different chiral precursors,namely,L-isomers of cysteine,glutathione,phenylglycine,and tryptophan.The resulting CDs consisted of O,N-doped(and also S-doped,in some cases)carbonized cores with surfaces rich in amide and hydroxyl groups;they exhibited high photoluminescence quantum yields reaching 57%,chiral optical signals in the Uv and visible spectral regions,and two-photon absorption.Chiral signals of CDs were rather complex and originated from a combination of the chiral precursors attached to the CD surface,hybridization of lower-energy levels of chiral chromophores formed within CDs,and intrinsic chirality of the CD cores.Using DFT analysis,we showed how incorporation of the chiral precursors at the optical centers induced a strong response in their circular dichroism spectra.The optical characteristics of these CDs,which can easily be dispersed in solvents of different polarities,remained stable during pH changes in the environment and after Uv exposure for more than 400 min,which opens a wide range of bio-applications.

关键词： properties chiral carbon

Structure,magnetic and adsorption properties of novel FePt/h-BN heteromaterials

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Nano Research 2023年第1期16卷 1473-1481页

作者： Anton S.Konopatsky vladislava v.Kalinina Alena S.Savchenko denis.v.Leybo Ekaterina v.Sukhanova viktor S.Baidyshev Zakhar I.Popov Andrey v.Bondarev Josef Polčák Dmitry v.Shtansky National University of Science and Technology(MISIS) Leninskiy prospect 4Moscow119049Russia Emanuel Institute of Biochemical Physics RAS Kosygina 4Moscow119334Russia Katanov Khakas State University 90 Lenin pr.655017 AbakanRussia Plekhanov Russian University of Economics 36 Stremyanny per.Moscow 117997Russia Department of Control Engineering Faculty of Electrical EngineeringCzech Technical University in PragueTechnicka 2Prague 16627Czech Republic CEITEC-Central European Institute of Technology Brno University of TechnologyPurkyňova 123Brno 61200 BrnoCzech Republic

Nanomaterials with high specific surface area and high absorption capacity are attracting increased interest aimed at imparting the desired magnetic properties.This work is devoted to the study of the effect of heat treatment in a hydrogen atmosphere on the microstructure,adsorption and magnetic properties of heterogeneous FePt/h-BN nanomaterials.Obtained via the polyol process,FePt nanoparticles(NPs)had a sizever the surface of hexagonal boron nitride(h-BN)nanosheets.The temperature-activated fcc→fct phase transformation in ultrafine FePt NPs has been well documented.FePt NPs act as active centers dissociating H2 molecules and transfer adsorbed hydrogen atoms to the h-BN.Density functional theory(DFT)calculations also indicate that the h-BN substrate can absorb hydrogen adsorbed on the FePt NPs.This hydrogen circulation in the FePt/h-BN system promoted the fcc→fct phase transformation and allowed to control the magnetic properties.FePt/h-BN nanomaterials also exhibited a high adsorption capacity with respect to various organic dyes.

关键词： FePt/h-BN nanomaterials polyol synthesis phase transformations magnetic properties adsorption

Diagnostic value ultrasound signs of stones less than or equal to 10 mm and clinicoradiological variants of ureteric colic

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Asian Journal of Urology 2023年第1期10卷 39-49页

作者： denis v.Krakhotkin volodymyr A.Chernylovskyi Kemal Sarica Arman Tsaturyan Evangelos Liatsikos Jurijus Makevicius Nikolay Yu Iglovikov Dmitry N.Pikhovkin Central District Hospital Outpatient ClinicSadovaya Lane 23KamenolomniRostov RegionRussia Private Urological Practice DniproUkraine Department of Urology Biruni University HospitalInstanbulTurkey Department of Urology University Hospital of PatrasPatrasGreece Department of Urology Medical University of ViennaViennaAustria Institute for Urology and Reproductive Health Sechenov UniversityMoscowRussia Institute of Clinical Medicine Faculty of MedicineVilnius UniversityVilniusLithuania Department and Clinic of Urology S.M.Kirov Military Medical Academy of the Ministry of Defense of the Russian FederationSt.PetersburgRussia Central District Hospital Department of SurgeryLenina Avenue 28AksayRostov RegionRussia

Objective:To determine the diagnostic value of ultrasound signs of urinary stones less than or equal to 10 mm and to determine clinico-radiological variants of ureteric colic.Methods:A total of 455 ultrasound investigations were performed in patients referring to emergency department with urolithiasis and symptoms suspected of ureteric colic between January 2021 and May 2021.In addition to microscopic evaluation of urine sediment to detect different crystals and non-contrast spiral computed tomography to detect stones,B-mode and color Doppler sonography was performed to assess the presence of acoustic shadow(AS)and twinkle artifacts(TA)as possible signs of stone(s)in ureter.Results:While the sensitivity and specificity of AS and TA were higher than 90%in patients with stones greater than 5 mm;positive prognostic values of these parameters were found to be extremely low for stones with sizes of 1-3 mm with specificity and sensitivity values not exceeding 53%.The sensitivity and specificity of AS and TA in the upper and lower ureters were higher for stones greater than or equal to 5 than for compared to those less than 5 mm.At the same time,the diagnostic values of TA and AS for middle ureter stones were very limited.The most prevalent clinico-radiological variants of ureteric colic were types I,III,and v being observed in 39%,28% and 21% cases,respectively.Conclusion:Our results demonstrate that TA and AS parameters seem to have a very low sensitivity and specificity in the diagnosis of urinary stones less than 5 mm.The diagnostic value of TA and AS increase significantly in stones greater than or equal to 5 mm.Therefore,clinicians need to be very careful for overestimating the diagnostic values of TA and AS for stones less than 5 mm and non-contrast spiral computed tomography must be the method of choice for patients presenting to emergency department with ureteric colic.

关键词： Ureteric colic Urolithiasis Ultrasound Twinkle artifact Non-contrast computed tomography

Hybrid Deep Learning Enabled Air Pollution Monitoring in ITS Environment

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Computers, Materials & Continua 2022年第7期72卷 1157-1172页

作者： Ashit Kumar Dutta Jenyfal Sampson Sultan Ahmad T.Avudaiappan Kanagaraj Narayanasamy Irina v.Pustokhina denis A.Pustokhin Department of Computer Science and Information Systems College of Applied SciencesAlMaarefa UniversityAd DiriyahRiyadh13713Kingdom of Saudi Arabia Department of Electronics and Communication Engineering Kalasalingam Academy of Research and EducationKrishnankoil626128India Department of Computer Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of Computer Science and Engineering K.Ramakrishnan College of TechnologyTiruchirappalli621112India Department of Computer Applications J.J College of Arts and Science(Autonomous)Affiliated to Bharathidasan UniversityPudukkottai622422India Department of Entrepreneurship and Logistics Plekhanov Russian University of Economics117997MoscowRussia Department of Logistics State University of Management109542MoscowRussia

Intelligent Transportation Systems(ITS)have become a vital part in improving human lives and modern economy.It aims at enhancing road safety and environmental quality.There is a tremendous increase observed in the number of vehicles in recent years,owing to increasing population.Each vehicle has its own individual emission rate;however,the issue arises when the emission rate crosses a standard value.Owing to the technological advances made in Artificial Intelligence(AI)techniques,it is easy to leverage it to develop prediction approaches so as to monitor and control air pollution.The current research paper presents Oppositional Shark Shell Optimization with Hybrid Deep Learning Model for Air Pollution Monitoring(OSSOHDLAPM)in ITS environment.The proposed OSSO-HDLAPM technique includes a set of sensors embedded in vehicles to measure the level of pollutants.In addition,hybridized Convolution Neural Network with Long Short-Term Memory(HCNN-LSTM)model is used to predict pollutant level based on the data attained earlier by the sensors.In HCNN-LSTM model,the hyperparameters are selected and optimized using OSSO algorithm.In order to validate the performance of the proposed OSSO-HDLAPM technique,a series of experiments was conducted and the obtained results showcase the superior performance of OSSO-HDLAPM technique under different evaluation parameters.

关键词： Deep learning air pollution environment monitoring internet of things intelligent transportation systems oppositional learning LSTM model

IoT-Cloud Empowered Aerial Scene Classification for Unmanned Aerial vehicles

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Computers, Materials & Continua 2022年第3期70卷 5161-5177页

作者： K.R.Uthayan G.Lakshmi vara Prasad v.Mohan C.Bharatiraja Irina v.Pustokhina denis A.Pustokhin vicente García Díaz Department of Information Technology Sri Sivasubramaniya Nadar College of EngineeringChennai603110India Department of Information Technology QIS College of Engineering&TechnologyOngole523001India Department of Electronics and Communications Engineering Saranathan College of EngineeringTrichy620012India Department of Electrical and Electronics Engineering SRMInstitute of Science and TechnologyChennai603203India Department of Entrepreneurship and Logistics Plekhanov Russian University of EconomicsMoscow117997Russia Department of Logistics State University of ManagementMoscow109542Russia Department of Computer Science University of OviedoOviedo33003Spain

Recent trends in communication technologies and unmanned aerial vehicles(UAvs)find its application in several areas such as healthcare,surveillance,transportation,etc.Besides,the integration of Internet of things(IoT)with cloud computing environment offers several benefits for the UAv communication.At the same time,aerial scene classification is one of the major research areas in UAv-enabledMEC systems.In UAv aerial imagery,efficient image representation is crucial for the purpose of scene classification.The existing scene classification techniques generate mid-level image features with limited representation capabilities that often end up in producing average results.Therefore,the current research work introduces a new DL-enabled aerial scene classificationmodel forUAv-enabledMECsystems.The presented model enables theUAvs to capture aerial imageswhich are then transmitted to MEC for further processing.Next,CapsuleNetwork(CapsNet)-based feature extraction technique is applied to derive a set of useful feature vectors from the aerial image.It is important to have an appropriate hyperparameter tuning strategy,since manual parameter tuning of DL model tend to produce several configuration errors.In order to achieve this and to determine the hyperparameters of CapsNetmodel,Shuffled Shepherd Optimization(SSO)algorithm is implemented.Finally,Backpropagation Neural Network(BPNN)classification model is applied to determine the appropriate class labels of aerial images.The performance of SSO-CapsNet model was validated against two openly-accessible datasets namely,UC Merced(UCM)Land Use dataset andWHU-RS dataset.The proposed SSO-CapsNet model outperformed the existing state-of-the-art methods and achieved maximum accuracy of 0.983,precision of 0.985,recall of 0.982,and F-score of 0.983.

关键词： Artificial intelligence mobile edge computing unmanned aerial vehicles deep learning optimization