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Variations of Dissolved Iron in the Amur River During an Extreme Flood Event in 2013

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Chinese Geographical Science 2016年第5期26卷 679-686页

作者： YAN Baixing GUAN Jiunian vladimir SHESTERKIN ZHU Hui Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences School of Environment Northeast Normal University Institute of Water and Ecology Problems Far Eastern Branch Russian Academy of Sciences

As a key factor limiting primary productivity in marine ecosystem, dissolved iron(DFe) export from fluvial systems has increased recently. There is particular concern about discharges of DFe during extreme flooding, when they are thought to increase considerably. An extreme flood event that caused inundation of extensive areas of Far Eastern Russia and Northeastern China occurred in the basin of the Amur River during summer and autumn 2013. During this event, water samples were collected in the middle reaches of the Amur River and the lower reaches at Khabarovsk City and analyzed for DFe concentrations and other aquatic parameters. The results show that the average DFe concentrations in the middle reaches of the Amur River(right bank) and at Khabarovsk were 1.11 mg/L and 0.32 mg/L, respectively, during the extreme flood in 2013. The total discharge of DFe during the flood event was 6.25 × 104 t. The high discharge of DFe during the flood reflects the elevated discharge of the river, hydrologically connected riparian wetlands, vast quantities of terrestrial runoff, and flood discharges from the Zeya and Bureya reservoirs. These results show that long-term monitoring is needed to identify and assess the impacts of DFe transport on the downstream reaches, estuarine area, and coastal ecosystems of the Amur River.

关键词： dissolved iron dissolved organic matter extreme flooding event land use the Amur River wetland

Experimental study on the performance of a rotational supercavitating evaporator for desalination

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Science China(Technological Sciences) 2014年第11期57卷 2115-2130页

作者： LIKHACHEV Dmitriy S LI FengChen KULAGIN vladimir A School of Energy Science and Engineering Harbin Institute of Technology Department of Heat Technology and Fluid Dynamics Siberian Federal University

Efforts have been made on experimental research of a supercavitation device for desalination, which is named rotational supercavitating evaporator （RSCE）. The RSCE is characterised by the simple construction and responsive capacity control, and only requires rough filtration of the source water for scaling- and fouling-free operations. The present study has been conducted for the water flow at temperature of around 22-30℃ and atmospheric pressure as the first step for investigation of the performance characteristics of RSCE. The multiply factor extremal experiments conducted with the Box-Wilson＇s method have revealed the salinity of the condensate, the temperature of steam inside the supercavity, and dependence of the shape of supercavity on the rate of steam extraction and rotation speed of impeller. The shape of impeller and the expected supercavitating effects it generates have been confirmed by experimental results at the rotation speed of 5430 rpm （round per minute）. The design of the steam extraction openings has been approved during the evacuation of steam. The experimental dependencies have been obtained in form of statistically valid regression equations, which can be used for engineering design of RSCE.

关键词： desalination cavitation technology thermal method steam extraction regression analysis

Neural network learns physical rules for copolymer translocation through amphiphilic barriers

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npj Computational Materials 2020年第1期6卷 1039-1046页

作者： Marco Werner Yachong Guo vladimir A.Baulin Institute Theory of Polymers Leibniz-Institut für Polymerforschung Dresden e.V.Hohe Straße 601069 DresdenGermany Departament d’Enginyeria Química Universitat Rovira i Virgili26 Av.dels Paisos Catalans43007 TarragonaSpain Kuang Yaming Honors School Nanjing University22 Hankou Road210093 NanjingChina

Recent developments in computer processing power lead to new paradigms of how problems in many-body physics and especially polymer physics can be *** processors can be exploited to generate millions of molecular configurations in complex environments at a second,and concomitant free-energy landscapes can be *** that are complete in terms of polymer sequences and architecture form a powerful training basis for cross-checking and verifying machine learning-based *** employ an exhaustive enumeration of polymer sequence space to benchmark the prediction made by a neural *** our example,we consider the translocation time of a copolymer through a lipid membrane as a function of its sequence of hydrophilic and hydrophobic ***,we demonstrate that massively parallel Rosenbluth sampling for all possible sequences of a polymer allows for meaningful dynamic interpretation in terms of the mean first escape times through the ***,we train a multi-layer neural network on logarithmic translocation times and show by the reduction of the training set to a narrow window of translocation times that the neural network develops an internal representation of the physical rules for sequencecontrolled diffusion *** on the narrow training set,the network result approximates the order of magnitude of translocation times in a window that is several orders of magnitude wider than the training *** investigate how prediction accuracy depends on the distance of unexplored sequences from the training window.

关键词： neural network narrow

Changes in filtration and capacitance properties of highly porous reservoir in underground gas storage:CT-based and geomechanical modeling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2982-2995页

作者： Valerii Khimulia vladimir Karev Yury Kovalenko Svyatoslav Barkov Ishlinsky Institute for Problems in Mechanics RAS Moscow119526Russia

The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage *** geomechanical part of the research included studying the dependence of rock permeability on the stress-strain state in the vicinity of the wells,and physical modeling of the implementation of the method of increasing the permeability of the wellbore zone-the method of directional unloading of the *** digital part of the research included computed tomography(CT)-based computer analysis of the internal structure,pore space characteristics,and filtration properties before and after the *** to the results of physical modeling of deformation and filtration processes,it is found that the permeability of rocks before fracture depends on the stress-strain state insignificantly,and this influence is ***,when downhole pressure reaches 7-8 MPa,macrocracks in the rock begin to grow,accompanied by irreversible permeability ***,geodesic tortuosity and permeability values were obtained based on digital studies and numerical modeling.A weak degree of transversal anisotropy of the filtration properties of rocks was *** on the analysis of pore size distribution,pressure field and flow velocities,high homogeneity and connectivity of the rock pore space is *** absence of pronounced changes in pore space characteristics and pore permeability after non-uniform triaxial loading rocks was *** the basis of geometrical analysis of pore space,the reasons for weak permeability anisotropy were *** filtration-capacitance properties obtained from the digital analysis showed very good agreement with the results of field and laboratory *** physical modeling has confirmed the efficiency of application of the directional unloading method for the reservoir under *** necessary parameters of its application were calcu

关键词： Permeability anisotropy Reservoir porosity Rocks computed tomography(CT) Digital core analysis Filtration flow numerical modeling

Overcoming thermo-optical dynamics in broadband nanophotonic sensing

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Microsystems & Nanoengineering 2021年第4期7卷 47-57页

作者： Mingkang Wang Diego J.Perez-Morelo vladimir Aksyuk Microsystems and Nanotechnology Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Institute for Research in Electronics and Applied Physics University of MarylandCollege ParkMD 20742USA

Advances in integrated photonics open up exciting opportunities for batch-fabricated optical sensors using high-quality-factor nanophotonic cavities to achieve ultrahigh sensitivities and *** sensitivity improves with increasing optical power;however,localized absorption and heating within a micrometer-scale mode volume prominently distorts the cavity resonances and strongly couples the sensor response to thermal dynamics,limiting the sensitivity and hindering the measurement of broadband time-dependent ***,we derive a frequency-dependent photonic sensor transfer function that accounts for thermo-optical dynamics and quantitatively describes the measured broadband optomechanical signal from an integrated photonic atomic force microscopy nanomechanical *** this transfer function,the probe can be operated in the high optical power,strongly thermo-optically nonlinear regime,accurately measuring low-and intermediate-frequency components of a dynamic signal while reaching a sensitivity of 0.7fm/Hz^(1/2) at high frequencies,an improvement of=10x relative to the best performance in the linear ***,we discover that a higher transduction gain and sensitivity are achieved with lower quality-factor optical modes for low signal *** limited to optomechanical transducers,the derived transfer function is generally valid for describing the small-signal dynamic responses of a broad range of technologically important photonic sensors subject to the thermo-optical effect.

关键词： dynamics regime hinder

Citation and bibliographic coupling between authors in the field of social network analysis

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Journal of Data and Information Science 2024年第4期9卷 110-154页

作者： Daria Maltseva vladimir Batagelj National Research University Higher School of Economics 101000 MoscowRussia Institute of Mathematics Physics and Mechanics1000 LjubljanaSlovenia University of Primorska Andrej MarušičInstitute6000 KoperSlovenia

Purpose:We analyzed the structure of a community of authors working in the field of social network analysis(SNA)based on citation indicators:direct citation and bibliographic coupling *** observed patterns at the micro,meso,and macro levels of ***/methodology/approach:We used bibliometric network analysis,including the“temporal quantities”approach proposed to study temporal *** a two-mode network linking publications with authors and a one-mode network of citations between the works,we constructed and analyzed the networks of citation and bibliographic coupling among *** used an iterated saturation data collection ***:At the macro-level,we observed the global structural features of citations between authors,showing that 80%of authors have not more than 15 citations from other *** the meso-level,we extracted the groups of authors citing each other and similar to each other according to their citation *** have seen a division of authors in SNA into groups of social scientists and physicists,as well as into other groups of authors from different *** found some examples of brokerage between different groups that maintained the common identity of the *** the micro-level,we extracted authors with extremely high values of received citations,who can be considered as the most prominent authors in the *** examined the temporal properties of the most popular *** limitations:The main challenge in this approach is the resolution of the author’s name(synonyms and homonyms).We faced the author disambiguation,or“multiple personalities”(Harzing,2015)*** remain consistent and comparable with our previously published articles,we used the same SNA data collected up to *** analysis and conclusions on the activity,productivity,and visibility of the authors are relative only to the field of *** implications:The proposed approach can be utilized for similar objectives and

关键词： Development of scientific fields Social network analysis Bibliographic network Temporal network Citation Bibliographic coupling

Microfracture Characterization in Sandstone Reservoirs:A Case Study from the Upper Triassic of Syria's Euphrates Graben

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Journal of Earth Science 2022年第4期33卷 901-915页

作者： Ibrahem Yousef vladimir Morozov Vladislav Sudakov Ilyas Idrisov Institute of Geology and Petroleum Technologies Kazan Federal UniversityKazan 420111Russia

The Euphrates Graben is located in eastern *** Upper Triassic Mulussa F Formation sandstones serve as the primary reservoir intervals in the majority of the graben *** study’s findings were based on core studies:petrographic examination of thin sections,scanning electron microscope(SEM),imaging of backscatter scanning electron microscope(BSE),X-ray microprobe examinations,and carbon-oxygen stable isotope analysis of microfracture-filling *** of the most common types of microfracture found in the investigated sandstones are intragranular or intracrystalline microfractures,grain boundary or grain-edge microfractures,and transgranular(crossing grains)*** microfractures that are open and free of secondary mineralization improve sandstone storage and ***,microfractures that are cemented and filled with secondary mineralization reduce storage and *** siderite and pyrite cements were identified within the microfractures and the nearby sandstone *** anhedral or euhedral siderites are thought to form during shallow burial diagenesis,whereas poikilotopic siderites are thought to form during deep burial *** pyrite is believed to be a diagenetic cement,which is attributed to the reduction of iron oxides present in the sediments in the presence of *** reflect tectonic,overpressure,and diagenetic *** of tectonic origin are associated with folding and thrust activities over the Euphrates Graben area,and they were formed at the beginning of the Upper Triassic with siderite and pyrite cement equilibration temperatures of approximately 100–105℃,and they continued forming from the middle to the end of the Upper Triassic with cement equilibration temperatures of approximately 90–100℃in conjunction with the first phase of the Euphrates *** related to diagenetic and overpressure processes are tension microfractures and wer

关键词： microfracture sandstone Upper Triassic Mulussa F Euphrates Graben Syria

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Discipline Impact Factor: Some of Its History, Some of the Author's Experience of Its Application, the Continuing Reasons for Its Use and… Next Beyond

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Journal of Data and Information Science 2020年第3期5卷 197-209页

作者： vladimir S.Lazarev Belarusian National Technical University 16 Yakub Kolas StMinsk220013Republic of Belarus

Purpose: This work aims to consider the role and some of the 42-year history of the discipline impact factor(DIF) in evaluation of serial publications. Also, the original "symmetric" indicator called the "discipline susceptibility factor" is to be presented. Design/methodology/approach: In accordance with the purpose of the work, the methods are analytical interpretation of the scientific literature related to this problem as well as speculative explanations. The information base of the research is bibliometric publications dealing with impact, impact factor, discipline impact factor, and discipline susceptibility ***: Examples of the DIF application and modification of the indicator are given. It is shown why research and university libraries need to use the DIF to evaluate serials in conditions of scarce funding for subscription to serial publications, even if open access is available. The role of the DIF for evaluating journals by authors of scientific papers when choosing a good and right journal for submitting a paper is also briefly discussed. An original indicator "symmetrical" to the DIF(the "discipline susceptibility factor") and its differences from the DIF in terms of content and purpose of evaluation are also briefly *** limitations: The selection of publications for the information base of the research did not include those in which the DIF was only mentioned, used partially or not for its original purpose. Restrictions on the length of the article to be submitted in this special issue of the JDIS also caused exclusion even a number of completely relevant publications. Consideration of the DIF is not placed in the context of describing other derivatives from the Garfield impact factor. Practical implications: An underrated bibliometric indicator, viz. the discipline impact factor is being promoted for the practical application. An original indicator "symmetrical" to DIF has been proposed in order of searching serial publicatio

关键词： Discipline impact factor Discipline susceptibility factor Citation analysis Journals evaluation Serials evaluation Information service

Cementation Characteristics and Their Effect on Quality of the Upper Triassic, the Lower Cretaceous, and the Upper Cretaceous Sandstone Reservoirs, Euphrates Graben, Syria

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Journal of Earth Science 2021年第6期32卷 1545-1562页

作者： Ibrahem Yousef vladimir Morozov Vladislav Sudakov Ilyas Idrisov Institute of Geology and Petroleum Technologies Kazan Federal UniversityKazanRussia

This article presents the results of cementation characteristics and their effect on sandstone reservoir quality of the Upper Triassic Mulussa F, the Lower Cretaceous Lower Rutbah, and the Upper Cretaceous Post Judea Sandstone formations in selected fields in the Euphrates Graben area, Syria. This study emphasises the role of cementation in the evaluation of the diagenetic history of the sediments, developing effective porosity, as well as evaluation of reservoirs stimulation procedures and potential for formation damage of the sandstone reservoirs. Quartz cement is present as well developed tabular or pyramidal syntaxial overgrowths. Kaolinite cement is present as vermicular aggregates which are most abundant within sandstones of the Mulussa F Formation. Carbonate cements include siderite and dolomite. Four lithofacies were identified within the studied formations;lithofacies-1 and 2 correspond to fluvial depositional environments, lithofacies-3 and 4 correspond to fluvial to estuarine channel environments. The Post Judea Sandstone and the Lower Rutbah reservoir units are typically lithofacies-3 sequences in which quartz overgrowths are the dominant cement. Because the total cement is more extensive in the Post Judea Sandstone Formation than in the Lower Rutbah Formation, resulting in high porosity(up to 26%) and permeability(6 000 mD), the reservoir quality is predicted to be best in the Post Judea Sandstone Formation. The reservoir units in the Mulussa F Formation contain the highest cement volumes comprised of early siderite and kaolinite, which, with the development of compaction-resisting quartz overgrowths and resultant compactional pore volume loss, has resulted in typically lower porosity being preserved than in the Lower Rutbah and Post Judea Sandstone formations.

关键词： cementation diagenesis reservoirs quality Euphrates Graben Syria