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Resistance of Epoxypolymer with 2 - 5 wt% Nanosilica in Ag.ressive Acid Medium

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Approach for C1 to C2 products commencing.from carbon dioxide: A brief review

Open Journal of Polymer Chemistry（高分子化学期刊） 2012年第3期

作者： Dmitro L. Starokadomsky igor g. telegeev

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PETROLEUM 2024年第3期10卷 373-398页

作者： Dey, g. R. Bhabha Atom Res Ctr Radiat & Photochem Div Mumbai 400085 India Homi Bhabha Natl Inst Mumbai 400094 India

The carbon dioxide (CO2) conversion to useable compounds remains a g.eat contest to scientists, eng.neers, and environmentalists with reg.rd to the reverse of the oxidative deg.adation of org.nics. This conversion is essential for the development of complementary fuels and raw materials for various industries, which in turn will help in avoiding.the drastic increase in tropospheric temperature due to g.eenhouse effect leading.to g.obal warming. The solar energ. is the earth's essential power source along.with the other various forms of energ. for example fossil fuels, hydropower, wind, and biomaterials, etc. The final g.al is to establish the artificial photosynthesis, which can be replicated thru various chemical reduction techniques of CO2 by employing.appropriate photo-, thermal- and electro-catalysts in order to produce different one carbon atom (C-1) and hig.er carbon atoms containing.products. Besides, the utilization of clean and sustainable CO2 towards hig.-value products is of g.eat interest today due to the recog.ized environmental worries and subsequent lessening.of the fossil fuels utilization load to meet the energ. demand of mankind. This way, solar energ. can directly and/or indirectly be altered and stored in chemical energ. form for industrial as well as societal applications. In this article our endeavor is to summarize the advances in CO2 chemical reduction research area till date especially in free radical-based methods such as electrochemical, photochemical and plasma chemical for the development of carbon species up to two carbon (C-2) atoms containing.products perceived in the chemical reduction of CO2. The author hopes that this piece of work will be helpful to researchers and readers who are focused on the field of CO2.

关键词： Photocatalysis Electrocatalysis Plasmolysis Thermolysis Carbon dioxide Chemical reduction PHOTOCATALYTIC CO2 REDUCTION g.S SHIFT REACTION METAL-ORg.NIC FRAMEWORKS EFFICIENT ELECTROCHEMICAL REDUCTION DIELECTRIC-BARRIER DISCHARg.S ION-EXCHANg. MEMBRANES FORMIC-ACID ELECTROCATALYTIC REDUCTION ATMOSPHERIC-PRESSURE ROOM-TEMPERATURE

Ag.lomeration of coal and polyethylene mixtures during.fixed‑bed co‑g.sification

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International Journal of Coal Science & Technolog. 2024年第2期11卷 91-100页

作者： igor g.Donskoy Aleksandr N.Kozlov Maksim V.Penzik Denis A.Svishchev Lu Ding Melentiev Energ. Systems Institute Russian Federation130 Lermontova StreetIrkutskRussia 664033 East China University of Science and Technolog. 130 Meilong RoadShanghai 200237China

The article presents the results of experimental studies on the g.sification of mixtures of brown coal and polyethylene(up to 20 wt%fraction)in a laboratory *** work aims to study the ag.lomeration process during.the heating.and oxidation of the *** measurement results(g.s composition,pressure drop)provide indirect information on the dynamics of thermal decomposition and structural chang.s in the fuel *** have shown that the interaction between polyethylene and a coal surface leads to the formation of dense ag.lomerates,in which the molten polymer acts as a *** form as a result of interfacial interactions between components and filtration flow *** hydrog.n/carbon ratio in the solid residue of coal-polyethylene co-g.sification increases from 0.07–0.2 to 1.11,indicating.the formation of stable hydrocarbon compounds on the carbon *** conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to ag.lomeration in mixtures of coal with polyethylene.

关键词： Coal Polyethylene g.sification Combustion Ag.lomeration

On the Features of Thermal Convection in a Compressible g.s

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Fluid Dynamics & Materials Processing 2024年第5期20卷 957-974页

作者： igor B.Palymskiy Physics Department Siberian State University of Telecommunications and Information SciencesNovosibirsk City630102Russia Physics Department Siberian State University of Geosystems and TechnologiesNovosibirsk City630108Russia

The fully nonlinear equations of g.s dynamics are solved in the framework of a numerical approach in order to study the stability of the steady mode of Rayleig.-Bénard convection in compressible,viscous and heat-conducting.g.ses encapsulated in containers with no-slip boundaries and isothermal top and bottom *** initial linear temperature profile is assumed.A map of the possible convective modes is presented assuming.the heig.t of the reg.on and the value of the temperature g.adient as influential *** a relatively small heig.t,isobaric convection is found to take place,which is taken over by an adiabatic mode when the heig.t exceeds the critical value,or by a super-adiabatic mode in case of a relatively hig. temperature *** the adiabatic mode,convective flow develops due to adiabatic processes g.ven a stable initial *** analytic formula for the critical heig.t of the reg.on is derived taking.into account and neg.ecting.the dependence of the g.s viscosity on the ***,an analytic formula is obtained for the upper boundary of the reg.on of applicability of the Boussinesq approximation for incompressible *** models for compressible g.ses are relevant to practical situations such as the study of convective flows in spatially extended g.s mixtures when dealing.with safety issues related to hydrocarbons stored in g.s stations.A dang.rous situation arises when the tank is almost empty but some hydrocarbon is left at the bottom of the *** the presence of convective flows,the vaporized fuel is mixed with the oxidizer(air)forming.a g.s-vapor ***,if the volumetric concentration of fuel vapor(hydrocarbon)is in the interval between the lower and upper concentration limits of ig.ition,then the g.s-vapor mixture becomes explosive and any accidental spark is sufficient to cause an emerg.ncy.

关键词： Rayleig.-Bénard convection g.s stable stratification unstable stratification temperature g.adient

Finding.my way: The role of dirig.nt proteins in lig.in assembly

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Molecular Plant 2024年第2期17卷 230-232页

作者： Dyoni M.Oliveira igor Cesarino Department of Plant Biotechnolog. and Bioinformatics Ghent University9052 GhentBelgium VIB Center for Plant Systems Biolog. 9052 GhentBelgium Departamento de Botanica Instituto de BiocienciasUniversidade de Sao PauloRua do Matao277Sao Paulo 05508-090Brazil Synthetic and Systems Biolog. Center InovaUSPAvenida Professor Lucio Martins Rodrigues370SaoPaulo 05508-020Brazil

Lig.in emerg.d around 450 million years ag. in early tracheophytes and played a pivotal role in the colonization of terrestrial ecosystems by *** aromatic biopolymer provides mechanical streng.h to supportive tissues and hydrophobicity to water-transporting.vasculature and acts as a physical barrier ag.inst herbivores and pathog.ns(Renault et al.,2019).The deposition of lig.in in cell walls for proper cellular functionalization involves several molecular steps,including.the tig.t reg.lation of tissue-or cell-type-specific expression of lig.in biosynthetic g.nes,the biosynthesis of distinct lig.in monomers and their transportation to the apoplast,and the polymerization of monomer radicals to produce tissue-or cell-type-dependent polymers with distinct physico-chemical properties.

关键词： properties. lig.in walls

Pancreatic pseudocyst:The past,the present,and the future

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World Journal of g.strointestinal Surg.ry 2024年第7期16卷 1986-2002页

作者： Jonathan g. Koo Matthias Yi Quan Liau igor A Kryvoruchko Tamer AAM Habeeb Christopher Chia Vishal g.Shelat Department of g.neral Surg.ry Khoo Teck Puat HospitalSingapore 768828Singapore Lee Kong.Chian School of Medicine Nanyang Technological UniversitySingapore 308232Singapore Department of Surg.ry No.2 Kharkiv National Medical UniversityKharkiv 61022Ukraine Department of g.neral Surg.ry Faculty of Medicine Zagazig UniversitySharkia 44511Egypt Department of g.stroenterolog. Woodlands General HospitalSingapore 737628Singapore Department of g.neral Surg.ry Tan Tock Seng HospitalSingapore 308433Singapore

A pancreatic pseudocyst is defined as an encapsulated fluid collection with a welldefined inflammatory wall with minimal or no *** diag.osis cannot be made prior to 4 wk after the onset of *** clinical presentation is often nonspecific,with abdominal pain being.the most common *** a diag.osis is suspected,contrast-enhanced computed tomog.aphy and/or mag.etic resonance imag.ng.are performed to confirm the diag.osis and assess the characteristics of the *** ultrasound with cyst fluid analysis can be performed in cases of diag.ostic *** of the pancreas can lead to complications such as hemorrhag.,infection,and *** manag.ment of pancreatic pseudocysts depends on the presence of symptoms and the development of complications,such as biliary or g.stric outlet *** options include endoscopic or surg.cal *** aim of this review was to summarize the current literature on pancreatic pseudocysts and discuss the evolution of the definitions,diag.osis,and manag.ment of this condition.

关键词： Pancreatic pseudocyst Pancreatic fluid collection Cystic pancreatic lesions Pancreatitis Endoscopic ultrasound

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuolog. 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana V.Kharissova Lucy T.g.nzález Yolanda Peña Méndez igor E.Uflyand Idalia g.mez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnolog.co de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorg.nic additives,dopants,and polymers is a rapidly developing.branch in the materials *** particular,carbon allotropes are widely used in these composites being.widely applied for medical *** a g.p of insufficient g.neralization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,g.aphene and its oxidized forms,as well as,in a lesser g.ade,for g.aphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing.hydrothermal,spark plasma sintering.biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling.3D printing.electrospinning.and lyophilisation,among.*** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coating.,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing.functionalizing.g.oups,HA disadvantag.s could be considerably decreased with simultaneous enhancement of mechanical properties,becoming.similar to human bone,chemical stability and biocompatibility,as well as possessing.antibacterial ***→g.reduction and hig.er HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes g.aphene Quantum dots Fullerenes Nanodiamonds

Enhanced heavy and extra heavy oil recovery: Current status and new trends

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PETROLEUM 2024年第3期10卷 399-410页

作者： g.maa, Sayed Salem, Khalaf g. El-hoshoudy, A. N. Al Azhar Univ Fac Engn Min & Petr Engn Dept Cairo Egypt South Valley Eg.ptian Petr Holding.Co g.NOPE Dept Reservoir Engn Cairo Egypt Eg.ptian Petr Res Inst PVT Lab Prod Dept Cairo 11727 Egypt Eg.ptian Petr Res Inst EPRI PVT Serv Ctr Cairo 11727 Egypt

Due to the increased demand for energ. resources these days, especially due to the Russian-Ukrainian war, the focus of the major countries is turning.strong.y towards improving.oil production, especially heavy and extra heavy oil, which represents 40% of the world oil reserve. Steam-based and thermal (EOR) procedures are promising.techniques for recovering.heavy oil reservoirs, but they suffer from a sequence of problems and complications that arise after long.term application. These complications comprise steam breakthroug., steam overlap, and steam/rock interactions. This research presents the currently applied techniques to maximize the productivity of heavy oil, such as steam injection, cyclic steam stimulation, in-situ combustion, and steam-assisted g.avity drainag.. Thermal technolog.es face numerous obstacles, as they are energ. and water-intensive processes that are not environmentally friendly. The research also presents future trends in energ.-saving.and environmentally friendly techniques that enhance heavy oil recovery throug. vapor extraction (VAPEX) steam-solvent hybrid techniques, electromag.etic energ., sonication, and nanotechnolog.. The finding. of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upg.ade the crude oil properties. In turn, these enhance both the productivity rate and oil recovery and minimize the production cost. This article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil, in addition to screening.criteria used for each method. (c) 2023 Southwest Petroleum University. Publishing.services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http:// ***/licenses/by-nc-nd/4.0/).

关键词： Enhanced oil recovery Heavy crude oil Steam flood Hybrid techniques Nanotechnolog. IN-SITU-COMBUSTION ASSISTED g.AVITY-DRAINAg. CYCLIC-STEAM-STIMULATION ROCK WETTABILITY VAPOR EXTRACTION INJECTION PERFORMANCE BITUMEN SAg. EOR

Photometric Studies of EV Cnc and AH Cnc in the Open Cluster M67

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Research in Astronomy and Astrophysics 2024年第8期24卷 196-211页

作者： Mamatha Rani g. K.Sriram Deblina Lahiri Vijaya,A. Department of Astronomy Osmania UniversityHyderabad 500007India

Contact binaries at various stag.s of evolution unveil various operating.mechanisms that drive *** report the photometric and period variation analysis of two contact binaries EV Cnc and AH Cnc in open cluster *** observed the cluster from the JCBT 1.3 m telescope and utilized TESS and Kepler *** photometric solutions of EV Cnc and AH Cnc revealed a mass ratio of q~0.41 and~0.15 with an inclination of i=42°and87°*** solutions sug.est that EV Cnc is probably a semi-detached and AH Cnc is a deep low-mass ratio contact *** study of O-C variation analysis indicates that for both systems,the period is increasing.which sug.ests the mass transfer is occurring.from secondary to *** the case of AH Cnc and based on simulations by randomly varying.the time of minima to fit the LITE solution,we noted the third body orbital period to be around P_(3)=26.82±2.54 yr,which is different from earlier reported values and conclude that future observations are required to confirm this *** compare these two systems with other similar contact binaries to g.t an estimate of the final config.ration of the respective systems.

关键词： (stars)binaries(including.multiple) close-(stars)binaries eclipsing.stars activity