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Friction 2024年第5期12卷 1042-1056页

作者： Anastasiya A.YAKOVENKO Irina G.GORYACHEVA Ishlinsky institute for problems in Mechanics RAS Moscow119526Russia

The contact of a rigid body with nominally flat rough surface and an elastic half-space is *** solve the contact problem,the Greenwood-Williamson statistical model and the localization principle are *** developed contact model allows us to investigate the surface approach and the real contact area with taking into account the asperities *** is shown that the mutual influence of asperities changes not only contact characteristics at the macroscale,but also the contact pressure distribution at the *** follows from the results,the inclusion in the contact model of the effect of the mutual influence of asperities is especially significant for studying the real contact area,as well as the contact characteristics at high applied *** results calculated according to the proposed approach are in a good agreement with the experimentally observed effects,i.e.,the real contact area saturation and the additional compliance exhaustion.

关键词： surface roughness elasticity Greenwood-Williamson model localization principle asperity interaction

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

Inherently Sinusoidal Single-phase Voltage Source Inverter Based on Modified Cuk Cell

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Chinese Journal of Electrical Engineering 2024年第1期10卷 114-123页

作者： Misbahul Munir Wisyahyadi Arwindra Rizqiawan Jihad Furqani School of Electrical Engineering and informatics Bandung Institute of TechnologyBandung 40132Indonesia

Renewable energy has become important for electricity generation because of the high air pollution associated with conventional fossil-based energy *** fossil-based power plants are gradually transitioning by incorporating renewable energy sources,such as photovoltaic(PV)*** a PV system,an inverter converts DC power from solar panels to AC power required to serve common electrical loads.A conventional H-bridge inverter topology has several disadvantages,such as the voltage being not sinusoidal,switching the DC voltage and high common-mode *** common-mode voltage can cause a large leaked capacitive current,which can result in undesirable operation in solar power applications.A common solution to this problem is the addition of a large filter to the input or output of an *** inherent sinusoidal voltage source inverter based on a modified Cuk converter as its basic cell,which simultaneously generates a sinusoidal output voltage and a lower common-mode voltage,is *** proposed topology does not require additional input or output *** expressions are derived to confirm the operation of the proposed *** results confirm the mathematical analysis.A laboratory-scale experiment is performed to verify the proposed inverter.

关键词： Voltage source inverter common-mode voltage capacitive current modified Cuk converter and sinusoidal waveform

Convection and Stratification of Temperature and Concentration

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1351-1364页

作者： Alexey Fedyushkin Laboratory of Complex Fluid Mechanics Ishlinsky Institute for Problems in Mechanics RASMoscow119526Russia

This study is devoted to an analysis of natural convection and the emergence of delamination in an incompressible fluid encapsulated in a closed region heated from the ***,medium and intensive modes of stationary laminar thermal and thermo-concentration convection are *** is shown that nonlinear flow features can radically change the flow structure and characteristics of heat and mass ***,the temperature and concentration segregation in the center of the square region display a non-monotonic dependence on the Grashof number(flow intensity).The formation of a nonstationary periodic structure of thermal convection in boundary layers and in the core of a convective flow in the closed region is also *** of the formation of countercurrents inside the region with the direction opposite to the main convective flow are ***,the influence of vertical and horizontal vibrations on oscillatory convection is analyzed in detail.

关键词： Natural convection stratification segregation numerical simulation vibrations

HIFs in hypoxic regulation of the extracellular matrix:focus on little-known player HIF-3

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BIOCELL 2024年第5期48卷 677-692页

作者： ALEKSANDRA GORNOSTAEVA LUDMILA BURAVKOVA MARGARITA LOBANOVA ELENA ANDREEVA institute of Biomedical problems of the Russian Academy of Sciences Khoroshevskoye Shosse 76AMoscow123007Russia

The structural and associated molecules of the extracellular matrix(ECM)complex is an important component of the local milieu of cells,both for maintaining their functions and *** is a dynamic structure that is finely tuned to changes in the *** of these factors is hypoxia,which can arise in tissues due to physiological or pathological *** a result of the hypoxic effect,the properties of the ECM are significantly modified,stiffness increases,the balance between degradation and synthesis of structural proteins shifts,and the deposition of biologically active mediators’***-inducible factors(HIFs)contribute significantly to the modification of the properties of the ECM under *** the three HIF isoforms,HIF-1 is the most studied,with numerous identified target genes encoding proteins that participate in all matrisome *** less is known about HIF-2 and *** the context of the effects of hypoxia on the matrisome,HIF-3 isoform is of particular *** the first two isoforms,transiently expressed during the first hours of hypoxia,HIF-3 is activated after around 24 h of exposure to hypoxia and persists for a longer *** addition,its transcription is more pronounced under hypoxia than are HIFs 1 and ***-3,rather than the first two isoforms,is possibly responsible for the changes that occur in matrisome during prolonged hypoxic *** review attempts to summarize the available data on the involvement of HIF-3 in the matrisome modification under hypoxia.

关键词： Hypoxia Hypoxia-inducible factors Matrisome

Factors Impacting Participatory Post‑Disaster Relocation and Housing Reconstruction:The Case of Tsholotsho District,Zimbabwe

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International Journal of Disaster Risk Science 2024年第1期15卷 58-72页

作者： Nombulelo Kitsepile Ngulube Hirokazu Tatano Subhajyoti Samaddar Department of Social informatics Graduate School of InformaticsKyoto UniversityKyoto 606-8507Japan Disaster Prevention Research institute(DPRI) Kyoto UniversityKyoto 611-0011Japan

Relocation is not typically considered the best planning option for post-disaster reconstruction and rehabilitation,but it may be necessary if the site has suffered severe damage or is at imminent *** is a growing recognition that strong community participation is necessary in the post-disaster relocation decision-making process since relocation can have detrimental effects on a community’s livelihood,cultural system,and way of life,among ***,the realization of this still needs to be *** of yet,few studies have examined a comprehensive account of meaningful community engagement in post-disaster relocation and reconstruction,particularly in developing *** study investigated what factors influenced local communities’ participation in post-disaster relocation and reconstruction works after the 2017Cyclone Dineo flood disaster in the Tsholotsho District of *** research methods such as face-to-face interviews,observations,and focus groups were used to collect qualitative data from a purposive sample of 25 community members and 6 *** empirical investigation showed that despite the fact that the relocation project was conceived as a community-centered project,there was no meaningful community engagement,due to the absence of a participatory framework or planning guidelines for stakeholder engagement,as well as the lack of political willingness among government *** study concluded that the lack of community involvement led to local communities abandoning the reconstruction sites because relocation projects failed to accommodate the cultural beliefs,place attachments,and livelihood concerns of local *** study suggested that it is imperative to enhance the awareness of government officials and other stakeholders about the importance of community participation for the effective implementation of post-disaster relocation *** community participation can also provide avenues fo

关键词： Community rehabilitation Housing reconstruction-Participatory relocation Zimbabwe

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The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： D A Baghdasaryan V A Harutynyan E M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia institute of Applied problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

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Real-time model correction using Kalman filter for Raman-controlled cell culture processes

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Chinese Journal of Chemical Engineering 2024年第6期70卷 251-260页

作者： Xiaoxiao Dong Zhuohong He Xu Yan Dong Gao Jingyu Jiao Yan Sun Haibin Wang Haibin Qu Pharmaceutical informatics institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Hisun Biopharmaceutical Co.Ltd. Hangzhou 311404China

Raman spectroscopy has found extensive use in monitoring and controlling cell culture *** this context,the prediction accuracy of Raman-based models is of paramount ***,models established with data from manually fed-batch cultures often exhibit poor performance in Raman-controlled ***,there is a need for effective methods to rectify these *** objective of this paper is to investigate the efficacy of Kalman filter(KF)algorithm in correcting Raman-based models during cell ***,partial least squares(PLS)models for different components were constructed using data from manually fed-batch cultures,and the predictive performance of these models was ***,various correction methods including the PLS-KF-KF method proposed in this study were employed to refine the PLS ***,a case study involving the auto-control of glucose concentration demonstrated the application of optimal model correction *** results indicated that the original PLS models exhibited differential performance between manually fed-batch cultures and Raman-controlled *** glucose,the root mean square error of prediction(RMSEP)of manually fed-batch culture and Raman-controlled culture was 0.23 and 0.40 g·L^(-1).With the implementation of model correction methods,there was a significant improvement in model performance within Raman-controlled *** RMSEP for glucose from updating-PLS,KF-PLS,and PLS-KF-KF was 0.38,0.36 and 0.17 g·L^(-1),***,the proposed PLS-KF-KF model correction method was found to be more effective and stable,playing a vital role in the automated nutrient feeding of cell cultures.

关键词： Raman spectroscopy Model correction Algorithm Model-predictive control Bioprocess

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Design and optimization of a greener sinomenine hydrochloride preparation process considering variations among different batches of the medicinal herb

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Chinese Journal of Chemical Engineering 2024年第7期71卷 77-90页

作者： Dandan Ren Jiale Xie Tianle Chen Haibin Qu Xingchu Gong Pharmaceutical informatics institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China National Key Laboratory of Chinese Medicine Modernization Zhejiang UniversityHangzhou 310058China Jinhua institute of Zhejiang University Jinhua 321016China

The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the processes are below 65 *** solve these problems,a new process using anisole as the extractant was *** exhibits high selectivity for sinomenine and can be connected to the subsequent water-washing *** alkalization of the medicinal material,heating extraction,water washing,and acidification crystallization were carried *** process was modeled and *** design space was *** recommended operating ranges for the critical process parameters were 3.0–4.0 h for alkalization time,60.0–80.0℃ for extraction temperature,2.0–3.0(volume ratio)for washing solution amount,and 2.0–2.4 mol·L^(-1) for hydrochloric acid *** new process shows good robustness because different batches of medicinal materials did not greatly impact crystal purity or sinomenine transfer *** sinomenine transfer rate was about 20%higher than that of industrial *** greenness score increased to 90 points since the novel process proposed in this research solves the problems of long process flow,high solvent toxicity,and poor atomic economy,better aligning with the concept of green chemistry.

关键词： Sinomenine hydrochloride Process optimization Anisole

Interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova Sergey V.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology institute for Metals Superplasticity problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University institute of Mechanical Science problems of RAS institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations Voids Boundary conditions