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Macrocellular vitreous carbon with the improved mechanical strength

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Frontiers of Materials Science 2015年第4期9卷 413-417页

作者： Oleg SMORYGO Alexander MARUKOVICH vitali mikutski Andika PRAMONO Powder Metallurgy Institute National Academy of Sciences of Belarus 41 Platonov str. Minsk 220005 Belarus Research Centre for Metallurgy and Materials Indonesian Institute of Sciences (LIPI) Kawasan Puspitek 470 Serpong 15314 Banten Indonesia

Vitreous carbons with regular macrocellular structure, open intercon- nected porosity, high specific strength and hydraulic permeability were synthesized by infiltration of the epoxy resin into the sacrificial template made from the carbamide granules. Polyvinylpyrrolidone （PVP） solution in ethanol was used as the template binder. When the resin setting and the template extraction had been performed, the resultant porous material was pyrolysed in the nitrogen flow. Depending on PVP concentration in the template binder, final vitreous carbons had the following properties： bulk density at 0.17-0.22g/cm3; porosity at 85.7%-89.0%; window size at 447-735pm; Darcian permeability coefficient at （0.64-9.5）×10-9m2; non-Darcian permeability coefficient at （0.53-3.36）×10-4 m. High specific strength of above 8×10^3 Pa/（kg.m-3） was attained.

关键词： vitreous carbon cellular material porous material

Tailoring properties of reticulated vitreous carbon foams with tunable density

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Frontiers of Materials Science 2016年第2期10卷 157-167页

作者： Oleg SMORYGO Alexander MARUKOVICH vitali mikutski Vassilis STATHOPOULOS Siarhei HRYHORYEU Vladislav SADYKOV Powder Metallurgy Institute National Academy of Sciences of Belarus 41 Platonov Str. Minsk 220005 Belarus Technological Educational Institute of Sterea Ellada Psahna Evias 34400 Greece Belarusian National Technical University 65 Nezavisimosty Ave. Minsk 220013 Belarus Boreskov Institute of Catalysis Sibrian Branch of Russian Academy of Sciences 5 Lavrentiev Ave. 630090 Novosibirsk Russia Novosibirsk State University 2 Pirogova Str. 630009 Novosibirsk Russia

Reticulated vitreous carbon （RVC） foams were manufactured by multiple replications of a polyurethane foam template structure using ethanolic solutions of phenolic resin. The aims were to create an algorithm of fine tuning the precursor foam density and ensure an open-cell reticulated porous structure in a wide density range. The precursor foams were pyrolyzed in inert atmospheres at 700℃, 1100℃and 2000℃, and RVC foams with fully open cells and tunable bulk densities within 0.09-0.42 g/cm3 were synthesized. The foams were characterized in terms of porous structure, carbon lattice parameters, mechanical properties, thermal conductivity, electric conductivity, and corrosive resistance. The reported manufacturing approach is suitable for designing the foam microstructure, including the strut design with a graded microstructure.

关键词： foam vitreous carbon reticulated cellular structure pyrolysis

提高悬浮浸渍开孔泡沫Inconel 625高温合金的烧结动力学和成分均匀性

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Transactions of Nonferrous Metals Society of China 2021年第8期31卷 2388-2401页

作者： Oleg SMORYGO vitali mikutski Anastasia VAZHNOVA Viachaslau HANCHAROU Serguei TIKHOV Vinod Kumar JANAGAM Amol Anant GOKHALE O.V Roman Powder Metallurgy Institute 41Platonov str.Minsk 220005Belarus Boreskov Institute of Catalysis Siberian BranchRussian Academy of Sciences5pr.LavrentievaNovosibirsk 630090Russia Defence Metallurgical Research Laboratory KanchanbaghHyderabad 500058India Indian Institute of Technology Bombay PowaiMumbai 400076India

采用悬浮液浸渍法制备开孔泡沫Inconel 625高温合金,先用混合粉末悬浮液复制纯镍泡沫带,然后进行热处理。本研究的目的是寻找一种合适的方法,在不使用低熔点添加剂的情况下,确保泡沫高温合金带的完全致密化,并在适中的烧结温度下获得均... 详细信息

采用悬浮液浸渍法制备开孔泡沫Inconel 625高温合金,先用混合粉末悬浮液复制纯镍泡沫带,然后进行热处理。本研究的目的是寻找一种合适的方法,在不使用低熔点添加剂的情况下,确保泡沫高温合金带的完全致密化,并在适中的烧结温度下获得均匀的化学成分。通过扫描电子显微镜和能谱仪对上述方法制备的泡沫带的显微组织和成分变化进行表征,并对其准静态压缩性能进行评估。结果表明,用Cr、Mo和Ni元素粉末作为高温合金粉末悬浮液的添加剂,在适中的烧结温度下,可获得化学成分均匀、密度高、符合Inconel 625标准的高温合金粉末悬浮液。这是因为低熔点共晶的形成,以及存在元素粉末时大的成分梯度所产生的非平衡热力学条件加速了扩散动力学。

关键词：高温泡沫合金悬浮液复制烧结扩散显微组织

Early selective enteral feeding in treatment of acute pancreatitis: A case report

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World Journal of Clinical Cases 2024年第3期12卷 637-642页

作者： Aleksei A Kashintsev Sergey V Anisimov Anastasya Nadeeva vitali Proutski Sergey V Anisimov Anastasya NadeevaVitali ProutskiPANDICA LTDLondon WC1N 3ESUnited Kingdom

BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute ***,the method of adminis-tration of enteral nutrition remains *** present the experience of treating a patient with moderate-severe acute pancreatitis,at high risk of progressing to a severe or fatal condition,using a novel method of selective feeding with duodenal *** SUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute *** a conventional treatment,the patient’s condition deteriorated by day 2 of *** an endoscopic approach,a novel catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of *** the isolated area created,a negative pressure was applied,followed by introduction of early selective enteral *** patient’s condition subsequently improved in a rapid manner,and no complications often associated with moderate-to-severe acute pancreatitis *** Within 48 h of starting treatment with the novel method,it can prevent the development of multiple organ failure and,when combined with minimally invasive drainage methods,help prevent infection.

关键词： Acute pancreatitis Enteral feeding Infectious complications Systemic inflammatory response syndrome MODS

Chemical Stability and Thermal Equation of State of SiN: Implications for Nitrogen Storage in the Deep Earth

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Journal of Earth Science 2024年

作者： Jingyi Zhang Shengxuan Huang Shan Qin Stella Chariton vitali B.Prakapenka Bin Chen Geodynamics Research Center Ehime University Center for Advanced Radiation Sources University of Chicago Hawai?i Institute of Geophysics and Planetology University of Hawai?i at Mānoa Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University

Most nitrogen is predicted to reside in the Earth’s interior and could be in the form of nitrides. In this study， the chemical reaction of Si3N4with SiO2was explored up to 50 GPa and 2600 K using laser-heated diamond anvil cells combined with synchrotron radiation X-ray diffraction. The experimental results demonstrate that Si3N4does not react with SiO2and cubic γ-Si3N4remains stable at extreme pressure and temperature. First-principles calculations were performed to investigate the chemical stability of Si3N4with the SiO2-MgO assemblage， showing that Si3N4can coexist with Mg2SiO4and MgSiO3polymorphs. Based on our thermal equation of state of cubic γ-Si3N4， we suggest that cubic γ-Si3N4is denser than the upper mantle but less dense than the lower mantle. The formation of Si3N4in the early Earth may contribute to the nitrogen preservation in the deep mantle soon after crystallization of the mantle and Si3N4is likely a precursor of nitrogen hosts in the modern deep Earth.

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Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO vitali THALÍA DOMÍNGUEZ BUCIO HAO LIU JOSÉMANUEL LUQUE GONZÁLEZ FRANCISCO JURADO-ROMERO ALEJANDRO ORTEGA-MOÑUX GLENN CHURCHILL JAMES C.GATES JAMES HILLIER NIKOLAOS KALFAGIANNIS DANIELE MELATI JENS H.SCHMID ILARIA CRISTIANI PAVEL CHEBEN J.GONZALO WANGÜEMERT-PÉREZ ÑIGO MOLINA-FERNÁNDEZ FREDERIC GARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(FWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal FWM-based system.

关键词： scattering pump modal

Gut-brain axis:does intestinal inflammation affect hippocampal neurogenesis and medulloblastoma development?

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Neural Regeneration Research 2023年第11期18卷 2381-2382页

作者： Arianna Casciati Mariateresa Mancuso Roberta vitali Simonetta Pazzaglia Biomedical Technologies Laboratory Agenzia Nazionale per le Nuove Tecnologiel’Energia e lo Sviluppo Economico Sostenibile(ENEA)RomeItaly

Gut-brain axis:does intestinal inflammation affect hippocampal neurogenesis and medulloblastoma development?Inflammatory bowel diseases (IBD) are a group of disorders that cause chronic inflammation in the intestines,associated with altered intestinal permeability,which in turn causes an immune response to enteric antigens in a gen etically susceptible *** incidence is high in industrialized countries and continuously rises in emerging economies.

关键词： inflammation diseases continuously

Construction strategies for a NATM tunnel in Sao Paulo, Brazil, in residual soil

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Underground Space 2022年第1期7卷 1-18页

作者： Osvaldo P.M.vitali Tarcisio B.Celestino Antonio Bobet Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907USA Sao Carlos School of Engineering University of Sao PauloSao CarlosSP 13566Brazil

Due to the fast growth of urban areas worldwide,the demand for tunnels in developed areas is *** design and construc-tion of those tunnels are complex because of their shallow depths and their interaction with existing aboveground and buried structures,which results in rather limited allowable ground deformations induced by the tunnel excavation and *** tropical regions,residual porous soils near the surface are *** soils are highly deformable;thus,tunneling may induce large ground deformations that may damage nearby *** new Austrian tunneling method(NATM)and the sprayed concrete lining(SCL)technique are being widely employed in several big cities in tropical regions,but little research has been conducted to assess the induced ground deformations in residual soils,common in tropical *** paper provides insight into this issue.A well-documented metro tunnel in Sa˜o Paulo,Brazil,in a residual red porous clay,was analyzed using 3D finite element method(FEM).The behavior of the residual red porous clay was approximated by an advanced constitutive soil model calibrated with triaxial tests on intact samples extracted at the *** of the tunnel deformations during construction matched the field *** calibrated model was then used to explore the tunnel per-formance under different construction *** influence of partial face excavation,unsupported span length,support stiffness and pipe roof umbrella were *** numerical results showed that partial face excavation was effective to reduce ground deformations ahead of the face of the tunnel and to improve face stability;however,the settlements behind the face increased because of the delay in closing the primary *** installation of a stiffer liner closer to the face reduced the ground deformations *** pipe roof umbrella was the most effective technique to reduce the ground deformations around the tunnel;however,the numerical results

关键词： Tunnel NATM Residual soil FEM 3D face effects Ground deformation Face stability

Poleward increase in feeding efficiency of leafminer Stigmella lapponica(Lepidoptera:Nepticulidae)in a latitudinal gradient crossing a boreal forest zone

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Insect Science 2023年第3期30卷 857-866页

作者： Mikhail V.Kozlov vitali Zverev Tobias M.Sandner Erik J.van Nieukerken Elena L.Zvereva Department of Biology University of TurkuTurkuFinland Department of Biology Philipps-Universitat MarburgMarburgGermany Naturalis Biodiversity Center Leidenthe Netherlands

Damage to plant communities imposed by insect herbivores generally decreases from low to high *** decrease is routinely attributed to declines in herbivore abundance and/or diversity,whereas latitudinal changes in per capita food consumption remain virtually ***,we tested the hypothesis that the lifetime food consumption by a herbivore individual decreases from low to high latitudes due to a temperature-driven decrease in metabolic *** 2016 to 2019,we explored latitudinal changes in multiple characteristics of linear(gallery)mines made by larvae of the pygmy moth,Stigmella lapponica,in leaves of downy birch,Betula *** mined leaves were larger than intact leaves at the southern end of our latitudinal gradient(at 60°N)but smaller than intact leaves at its northern end(at 69°N),suggesting that female oviposition preference changes with *** latitudinal changes were observed in larval size,mine length or area,and in per capita food consumption,but the larval feeding efficiency(quantified as the ratio between larval size and mine size)increased with ***,*** larvae consumed less foliar biomass at higher latitudes than at lower latitudes to reach the same *** on space-for-time substitution,we suggest that climate warming will increase metabolic expenses of insect herbivores with uncertain consequences for plant-herbivore interactions.

关键词： Betula pubescens climate change food quality insect herbivory metabolic expenses oviposition preference