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Study of asphaltene reaggregation in toluene/heptane mixture by dynamic and static light scattering

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Petroleum Research 2024年第1期9卷 48-54页

作者： vladimir n.Kuryakov Oil and Gas Research Institute of RAS(OGRI RAS) Gubkina Str.3119333MoscowRussian Federation

This paper presents the study of the effect of multiple ultrasonic impacts on submicron asphaltene aggregates in a toluene/heptane solution,conducted with dynamic light scattering *** objects of the study were four samples of asphaltenes obtained from four different *** all samples,the change in the average size of the asphaltene submicron aggregates with time was measured after the addition of a precipitant(heptane)to a solution of asphaltenes in toluene at an amount above the threshold *** aggregates formed in solution after the addition of the precipitant and were subjected to ultrasonic treatment,which led to the destruction of the asphaltene *** of destroyed asphaltenes was *** kinetics of this aggregation were similar to the kinetics of aggregation of asphaltenes after the addition of a *** iterations of asphaltene aggregate destruction in the sample led to a significant change in the kinetics of aggregation:the growth of aggregates slowed and stabilized at a size of approximately 200 nm and 30 nm for the different studied samples.

关键词： Asphaltenes Aggregation Sonication Dynamic light scattering Re-aggregation Colloidal stability Resins

Inversion of walkaway VSP data in the presence of lateral velocity heterogeneity

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Energy Geoscience

Energy Geoscience 2024年第2期5卷 304-313页

作者： vladimir Grechka Ilya Tsvankin Pedro Contreras CWP Department of GeophysicsColorado School of MinesGoldenCO80401USA PDVSA-InTEVEP Apartado 76343Caracas1070AVenezuela Borehole Seismic LLC USA Department of Physics ULAVenezuela

Multi-azimuth walkaway vertical seismic profiling is an established technique for the estimation of in situ slowness surfaces and inferring anisotropy ***,this technique requires the assumption of lateral homogeneity,which makes the horizontal slowness components at depths of downhole receivers equal to those measured at the *** violations of this assumption,such as lateral heterogeneity or nonzero dip of intermediate interfaces,lead to distortions in reconstructed slowness surfaces and,consequently,to errors in estimated anisotropic *** this work,we relax the assumption of lateral homogeneity and discuss how to correct vertical seismic profile data for weak lateral *** describe a procedure of downward continuation of recorded traveltimes that accounts for the presence of both vertical inhomogeneity and weak lateral heterogeneity,which produces correct slowness surfaces at depths of downhole receivers,noticing that sufficiently dense receiver coverage along a borehole is required to separate influences of vertical and lateral heterogeneity on measured traveltimes and obtain accurate estimates of the slowness *** the slowness surfaces are found and a desired type of anisotropic model to be inverted is selected,the corresponding anisotropic parameters,providing the best fit to the estimated slownesses,can be *** invert the slowness surfaces of P-waves for parameters of the simplest anisotropic model describing dipping fractures(transversely isotropic medium with a tilted symmetry axis).Five parameters of this model,namely,the P-wave velocity V0 in the direction of the symmetry axis,Thomsen's anisotropic coefficients e and d,the tilt n,and the azimuth b of the symmetry axis,can be estimated in a stable manner when maximum source offset is greater than half of receiver depth.

关键词： Walkaway vertical seismic profile Lateral velocity heterogeneity Anisotropic parameter estimation Vertical inhomogeneity

Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases

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World Journal of Gastroenterology 2024年第11期30卷 1524-1532页

作者： Yi-Fan Chang Jia-Jing Li Tao Liu Chong-Qing Wei Li-Wei Ma vladimir n nikolenko Wei-Long Chang Department of Gastrointestinal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Pathology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Clinical Laboratory The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Human Anatomy and Histology I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991Russia

Autophagy is a cellular catabolic process characterized by the formation of double-membrane *** electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and degradation.A large number of studies have shown that autophagy is closely related to the digestion,secretion,and regeneration of gastrointestinal(GI)***,the role of autophagy in GI diseases remains *** article focuses on the morphological and biochemical characteristics of autophagy in GI diseases,in order to provide new ideas for their diagnosis and treatment.

关键词： Autophagy Morphological study Biochemical characteristics Subcellular structure Transmission electron microscopy Gastrointestinal diseases

Superior piezoelectric performance with high operating temperature in bismuth ferrite-based ternary ceramics

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Journal of Materials Science & Technology 2024年第2期169卷 172-181页

作者： Yunyao Huang Leiyang Zhang Ruiyi Jing Yang Yang vladimir Shur Xiaoyong Wei Li Jin Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China School of natural Sciences and Mathematics Ural Federal UniversityEkaterinburg620000Russia

Due to the thermal depolarization effect,adequate piezoelectric performance with high operating temperature is regarded to be challenging to accomplish concurrently in piezoceramics for applications in specific piezoelectric *** this work,we synthesized(0.8−x)BiFeO_(3)-x PbTi_(3)-0.2Ba(Zr_(0.25)Ti_(0.75))O_(3)(abbreviated as BFO-x PT-BZT)ternary solid solutions with 0.15≤x≤0.30 by conventional solid-state reaction *** MPB composition with a coexisting state of rhombohedral-tetragonal phases exhibits enhanced electromechanical properties,including Curie temperature of 380℃,large-signal equivalent piezoelectric coefficient d^(∗)_(33)of 395 pm V^(-1),small-signal piezoelectric coefficient d_(33)of 302 pC n^(-1),and electromechanical coupling factor k_(p)of 50.2%,which is comparable to commercial PZT-5A ceramics,indicating potential in high-temperature ***,in-situ X-ray diffraction(XRD)and piezoelectric force microscopic(PFM)techniques demonstrate that multiphase coexistence and complex nanodomains promote piezoelectric response via *** x=0.24 composition exhibits the highest in-situ d_(33)of 577 pC n^(-1)and good temperature stability in 30−280℃,indicating that BZT-modified BFO-PT ceramics are promising candidates for high-temperature piezoelectric devices.

关键词： High-temperature piezoelectrics Morphotropic phase boundary In-situ technique Domain structure BFO

Outcomes of long-acting injectable antipsychotics use in pregnancy:A literature review

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World Journal of Psychiatry 2024年第4期14卷 582-599页

作者： Ana V Pejčić Srdjan M Stefanović Milošn Milosavljević vladimir S Janjić Marko M Folić nevena D Folić Jovana Z Milosavljević Department of Pharmacology and Toxicology Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Department of Pharmacy Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Department of Clinical Pharmacology University Clinical Center KragujevacKragujevac 34000Serbia Department of Psychiatry Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Clinic for Psychiatry University Clinical Center KragujevacKragujevac 34000Serbia Center for Pharmaceutical and Pharmacological Research Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Department of Pediatrics Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Pediatric Clinic University Clinical Center KragujevacKragujevac 34000Serbia Department of Anatomy Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia

BACKGROUnD Women with a history of serious psychotic disorders are at increased risk of disease relapse during ***-acting injectable(LAI)antipsychotics have been widely used to improve adherence and prevent relapse in patients with various severe psychotic disorders,but there is a lack of high-quality data from previous research on the safety of LAI antipsychotics during *** To summarize relevant data on maternal,pregnancy,neonatal,and developmental outcomes from published cases of LAI antipsychotic use in *** A literature search was performed through november 11,2023,using three online databases:PubMed/MEDLInE,Scopus,and Web of *** reports or case series that reported information about the outcomes of pregnancy in women who used LAI antipsychotics at any point in pregnancy,with available full texts,were *** statistics,narrative summation,and tabulation of the extracted data were *** A total of 19 publications satisfied the inclusion criteria:3 case series,15 case reports,and 1 conference *** reported the outcomes of LAI antipsychotic use in 74 women and 77 *** use of secondgeneration LAI antipsychotics was reported in the majority(n=47;61.0%)of ***-generation LAI antipsychotics were administered during 30 pregnancies(39.0%).Most of the women(approximately 64%)had either satisfactory control of symptoms or no information about relapse,while approximately 12%of them had developed gestational diabetes mellitus.A minority of cases reported adverse outcomes such as stillbirth,spontaneous abortion,preterm birth,low birth weight,congenital anomalies,and neurological manifestations in ***,there were no reports of negative long-term developmental *** Currently available data seem reassuring,but further well-designed studies are required to properly evaluate the risks and benefits of LAI antipsychotic use during pregnancy.

关键词： Antipsychotic agents Long-acting injectable Pregnancy Outcome Review

Arctic Sea Ice Variations in the First Half of the 20th Century:A new Reconstruction Based on Hydrometeorological Data

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Advances in Atmospheric Sciences 2024年第8期41卷 1483-1495,1686-1693页

作者： vladimir A.SEMEnOV Tatiana A.ALDOnInA Fei LI noel Sebastian KEEnLYSIDE Lin WAnG A.M.Obukhov Institute of Atmospheric Physics RAS Moscow 119017Russia Institute of Geography RAS Moscow 119017Russia Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway nansen Environmental and Remote Sensing Center Bergen 5007Norway Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The shrinking Arctic sea-ice area(SIA) in recent decades is a striking manifestation of the ongoing climate *** of the Arctic sea ice have been continuously observed by satellites since 1979, relatively well monitored since the 1950s, but are highly uncertain in the earlier period due to a lack of observations. Several reconstructions of the historical gridded sea-ice concentration(SIC) data were recently presented based on synthesized regional sea-ice observations or by applying a hybrid model–empirical approach. Here, we present an SIC reconstruction for the period1901–2019 based on established co-variability between SIC and surface air temperature, sea surface temperature, and sea level pressure patterns. The reconstructed sea-ice data for March and September are compared to the frequently used Had ISST1.1 and SIBT1850 datasets. Our reconstruction shows a large decrease in SIA from the 1920 to 1940 concurrent with the Early 20th Century Warming event in the Arctic. Such a negative SIA anomaly is absent in Had ISST1.1 data. The amplitude of the SIA anomaly reaches about 0.8 mln km^(2) in March and 1.5 mln km^(2) in September. The anomaly is about three times stronger than that in the SIBT1850 dataset. The larger decrease in SIA in September is largely due to the stronger SIC reduction in the western sector of the Arctic Ocean in the 70°–80°n latitudinal zone. Our reconstruction provides gridded monthly data that can be used as boundary conditions for atmospheric reanalyses and model experiments to study the Arctic climate for the first half of the 20th century.

关键词： Arctic sea ice Arctic climate early 20th century warming climate variability

Effect of the anionic composition of sulfolane based electrolytes on the performances of lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第8期95卷 231-240,I0005页

作者： Elena V.Karaseva Elena V.Kuzmina Bo-Quan Li Qiang Zhang vladimir S.Kolosnitsyn Ufa Institute of Chemistry of the Ufa Federal Research Centre of the Russian Academy of Science 71Prospect OktyabryaUfa 450054BashkortostanRussia Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

In lithium-sulfur batteries,cell design,specifically electrolyte design,has a key impact on the battery *** effect of lithium salt anion donor number(Dn)(Dn[PF_(6)]^(-)=2.5,Dn[n(SO_(2)CF_(3))_(2)]^(-)=5.4,Dn[ClO_(4)]^(-)=8.4,Dn[SO_(3)CF_(3)]^(-)=16.9,and Dn[nO_(3)]^(-)=21.1)on the patterns of lithium-sulfur batteries and lithium metal electrode performances with sulfola ne-based electrolytes is *** increase in Dn of lithium salt anions leads to an increase in the depth and rate of electrochemical reduction of sulfur and long-chain lithium polysulfides and to a decrease in those for medium-and short-chain lithium *** of lithium salt anions has weak effect on the discharge capacity of lithium-sulfur batteries and the Coulomb efficiency during cycling,with the exception of LiSO_(3)CF_(3)and LinO_(3).An increase in Dn of lithium salt anions leads to an increase in the cycling duration of lithium metal anodes and to a decrease in the presence of lithium *** sulfolane solutions of LinO_(3)and LiSO_(3)CF_(3),lithium polysulfides do not affect the cycling duration of lithium metal anodes.

关键词： Donor number Lithium salt Sulfolane Lithium polysulfide Electrolyte Lithium-sulfur battery Lithium metal electrode

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

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 *** 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 ***,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 *** 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 ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** 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+*** 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 ***,the title compound is paramagnetic above 4 K.

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