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A Recursive Probabilistic Inversion of Satellite Gradiometry Data for the Upper Mantle Density Variation

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 7-8页

作者： Alexander MINAKOV dmitriy KOLYUKHIN The Centre for Earth Evolution and Dynamics University of OsloBoks 1072 Blindern0316 OsloNorway A.A.Trofimuk Institute of Petroleum Geology and Geophysics SB RAS NovosibirskRussia

We describe a method to perform a constrained lithospheric-scale inversion of satellite gravity gradient *** a priori constraints include:i)data covariance matrix;ii)prior model covariance matrix including a model for... 详细信息

关键词： lithosphere earth’s structure potential fields inverse problems satellite gradiometry north Atlantic

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

Rheological study of nanoparticle-based cationic surfactant solutions

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Petroleum 2022年第4期8卷 522-528页

作者： Ayomikun Bello Joy Ozoani Adewale Adebayo dmitriy Kuriashov Skolkovo Institute of Science and Technology MoscowRussia Moscow Engineering Physics Institute MoscowRussia Higher School of Economics MoscowRussia Kazan National Research Technological University KazanRussia

Worm-like micelles are of special interest among the many forms of surfactant aggregates because of their usefulness in research and *** are elongated,flexible aggregates formed by amphiphilic molecules spontaneously self-organizing in *** nature of the surfactant determines its unique shape,which may be altered by mixing it with other substances or changing physicochemical variables like as temperature,pH,or *** rheology of viscoelastic fluid systems is currently being modified using *** method,which was just introduced about 10 years ago,has shown to be highly promising,producing significant improvements in rheological properties,particularly at reservoir *** goal of this research is to investigate and assess the rheology of an aqueous cationic surfactant solution based on graphene oxide *** thermodynamics,structure and rheology of nanoparticle-based cationic surfactant solutions were investigated *** to structural and thermodynamic investigations in surfactant-nanoparticle mixtures,micellenanoparticle interactions arise as physical crosslinks between *** existence of these interactions is shown to generate considerable viscosity and viscoelasticity in wormlike micelles,even when the fluid is Newtonian in the absence of *** viscosity,shear modulus and relaxation time all increase as particle concentration *** nanoparticles generates a network of micellar entanglements as a result of *** results demonstrate that adding nanoparticles to surfactant solutions provides for a one-of-a-kind method of altering fluid rheology under a range of circumstances.

关键词： Surfactant Wormlike micelles Nanoparticles Viscosity Modulus Rheology

Heart Rate Extraction from Vowel Speech Signals

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Journal of Computer Science & Technology 2012年第6期27卷 1243-1251页

作者： Abdelwadood Mesleh dmitriy Skopin Sergey Baglikov Anas Quteishat Computer Engineering Department Faculty of Engineering TechnologyAl-Balqa' Applied UniversityAmmanJordan Help MediCom Group KurskRussia

This paper presents a novel non-contact heart rate extraction method from vowel speech signals. The proposed method is based on modeling the relationship between speech production of vowel speech signals and heart activities for humans where it is observed that the moment of heart beat causes a short increment （evolution） of vowel speech formants. The short-time Fourier transform （STFT） is used to detect the formant maximum peaks so as to accurately estimate the heart rate. Compared with traditional contact pulse oximeter, the average accuracy of the proposed non-contact heart rate extraction method exceeds 95%. The proposed non-contact heart rate extraction method is expected to play an important role in modern medical applications.

关键词： electrocardiogram feature extraction heart rate short-tlme Fourier transform vowel speech signal

CO_(2)-Free Calcium Carbide Manufacturing: Demanded Strategy in the Carbon-Neutral Chemical Industry

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Chinese Journal of Chemistry 2023年第24期41卷 3611-3617页

作者： dmitriy E.Samoylenko Konstantin S.Rodygin Valentine P.Ananikov Institute of Chemistry Saint Petersburg State University7/9 Universitetskaya nabSt.Petersburg199034 Russia Zelinsky Institute of Organic Chemistry Russian Academy of SciencesLeninsky pr.47Moscow119991 Russia

Calcium carbide is considered a possible key component in the sustainable carbon cycle,including convenient recycling of carbon wastes to industrial ***,currently employed CaC2 manufacturing process produces significant amounts of CO_(2).One of the main factors of its appearance is the formation of carbon oxide during the *** reaction of lime ore with coal inevitably results in the formation of CO and the loss of one carbon *** is usually burnt,forming CO_(2) to maintain the required high temperature during synthesis – 2200 ℃.In the present study,we discuss that the use of calcium metal instead of lime represents a good opportunity to prevent CO_(2) emission since the reaction of Ca with carbon occurs in an atom-efficient manner and results in only CaC_(2) at a much lower temperature of 1100 ℃.Here,the reaction of Ca with carbon was successfully tested to synthesize CaC_(2).The desired product was isolated in gram-scale amounts in 97.2% yield and 99% *** environmental friendliness of the proposed method originates from the calculations of the *** is provided concerning the cost factor of Ca within the considered process.

关键词： CO_(2)emission CaC_(2) Carbon cycle Sustainable chemistry Green chemistry

Operational method for determining bottom hole pressure in mechanized oil producing wells,based on the application of multivariate regression analysis

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Petroleum Research 2021年第4期6卷 351-360页

作者： Inna N.Ponomareva Vladislav I.Galkin dmitriy A.Martyushev Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPermRussia614990 Department of Oil and Gas Geology Perm National Research Polytechnic UniversityPermRussia614990

One of the major tasks of monitoring production well operations is to determine bottom-hole flowing *** overwhelming majority of wells in the Perm Krai are serviced using borehole pumps,which makes it difficult to take direct bottom-hole flowing pressure *** bottomhole filtration pressure(BHFP)in these wells is very often determined by recalculating the parameters measured at the well mouth(annulus pressure,dynamic fluid level depth).The recalculation is done by procedures based on analytically determining the characteristics of the gas-liquid mixture in the wellbore,which is very inconsistent to perform due to the mixture's complex *** article proposes an essentially different approach to BHFP measurements that relies on the mathematical processing of the findings of more than 4000 parallel mouth and deep investigations of the oil production wells of a large oil-production *** a result,multivariate mathematical models are elaborated that allow reliably determining the BHFP of oil-production wells in operation.

关键词： Production well Bottom-hole flowing pressure BHFP determination Technique Multivariate statistical model Regression analysis Multilevel modeling

Cationic Polymerization of Isobutylene and C4 Mixed Feed Using Complexes of Lewis Acids with Ethers: A Comparative Study

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Chinese Journal of Polymer Science 2019年第9期37卷 891-897页

作者： dmitriy I. Shiman Ivan A. Berezianko Irina V. Vasilenko Sergei V. Kostjuk Research Institute for Physical Chemical Problems of the Belarusian State University 14 Leningrads kaya St. Minsk 220006 Belarus Department of Chemistry Belarusian State University 14 Leningradskaya st. Minsk 220006 Belarus Sechenov First Moscow State Medical University Institute for Regenerative Medicine 8-2 Trubetskaya st. Moscow 119991 Russia

The cationic polymerization of C4 mixed feed and isobutylene co-initiated by AlCl3xOiPr2,iBuAlC12xnOiPr2, and [emim]Cl- FeCl3xnOiPr2 ([emim]Cl: 1 -ethyl-3-methylimidazolium chloride) has been investigated. AlCl3xOiPr2 co-initiated cationic polymerization of C4 mixed feed proceeds at a lower rate than polymerization of isobutylene affording polymers with higher molecular weight. Complexes of iBuAlCh with di isopropyl ether of different compositions are more suitable co-initiators than AlCl3xOiPr2 for the synthesis of highly reactive polyisobutylene (HR PIB) from C4 mixed feed due to their higher activity in the polymerization as well as possibility to prepare polyisobutylenes with lower molecular weight and higher content of exo-olefin end groups. However, iBuA1C12 needs activating via addition of external water (initiator) and/or interaction with salts hydrates in order to increase the reaction rate and the saturated monomer conversion.[Emim]Cl-FeC13/iPr2O is a quite promising catalyst for the preparation of HR PIB with high exo-olefin end group content (> 80%) and relatively low polydispersity (Mw/Mn < 2.8) via cationic polymerization of C4 mixed feed. The sonication of reaction mixture in case of using [emim]Cl-FeCh allowed increasing the reaction rate and decreasing the molecular weight.

关键词： Cationic polymerization Isobutylene C4 mixed feed Highly reactive polyisobutylene

Studying the direction of hydraulic fracture in carbonate reservoirs:Using machine learning to determine reservoir pressure

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Petroleum Research 2023年第2期8卷 226-233页

作者： dmitriy A.Martyushev Inna N.Ponomareva Evgenii V.Filippov Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm614990Russia Department of Oil and Gas Fields Development LLC《LUKOIL-PERM》Perm614068Russia

Hydraulic fracturing(HF)is an effective way to intensify oil production,which is currently widely used in various conditions,including complex carbonate *** the conditions of the field under consideration,the hydraulic fracturing leads to a significant differentiation of technological efficiency indicators,which makes it expedient to study the patterns of crack formation in *** were carried out for all wells,which were considered as the objects of impact,to assess the spatial orientation of the cracks *** developed indirect method was used for this purpose,the reliability of which was confirmed by geophysical *** the analysis,it was found that in all cases,the crack is oriented in the direction of the section of the development system element characterized by the maximum reservoir *** the same time,the reservoir pressure values for all wells were determined at one point in time(at the beginning of HF)using machine learning *** reliability of the machine learning methods used is confirmed by the high convergence with the actual(historical)reservoir pressures obtained during hydrodynamic studies of *** obtained conclusion about the influence of the reservoir pressure on the patterns of fracture formation should be taken into account when planning hydraulic fracturing under the conditions studied.

关键词： Hydraulic fracturing direction Machine learning Actual field data Correlation coefficient Well flow rate Well geophysical studies Carbonate reservoir

Calcium Carbide:From Elemental Carbon to Isotope-Economic Synthesis of^(13)C_(2)-Labeled Heterocycles

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Chinese Journal of Chemistry 2023年第21期41卷 2810-2818页

作者： Maria S.Ledovskaya Vladimir V.Voronin Nikita R.Valov dmitriy E.Samoylenko Saint Petersburg State University Institute of ChemistryUniversitetsky prospect 26Peterhof198504 Russia

^(13)C-Carbon is the most available source of *** is a relatively inexpensive solid material,which can be easily converted to calcium carbide-^(13)C_(2).In current work,Ca^(13)C_(2)was used for in situ generation of^(13)C_(2)-acetylene in 1,3-dipolar cycloaddition and[4+2]cycloaddition *** the first time,1H-1,2,3-triazoles-4,5-^(13)C_(2)and isoxazoles-4,5-^(13)C_(2)were synthesized using calcium carbide-^(13)C_(2).A Diels-Alder type cycloaddition of 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine and Ca^(13)C_(2)was investigated,and the best way for the synthesis of 3,6-di(pyridin-2-yl)pyridazine-4,5-^(13)C_(2)was proposed for the first *** we perform a detailled description of NMR spectra of^(13)C_(2)-labeled triazoles,isoxazoles and 3,6-di(pyridin-2-yl)pyridazine.

关键词： Isotopic labeling Cycloaddition Click chemistry Sustainable Chemistry Calcium carbide