检索结果-南通市图书馆

色谱 2005年第4期23卷 347-352页

作者： BARAKAT Y IBRAHIM V MoSTAFA n E shaker n o Egyptian Petroleum Research Institute Cairo EgyptEgyptian Petroleum Research Institute Cairo EgyptEgyptian Petroleum Research Institute Cairo EgyptEgyptian Petroleum Research Institute Cairo Egypt

Some polarity terms of two groups of nitrogen-containing surfactants （six alkanolamides and nine polyoxyethylenated long chain amines） are measured through gas chromatography. The apparent methanol carbon number (CMeoH) and polarity index （IP） values are determined on the investigated surfactants as stationary phases in packed columns. Similarly, CMeoH and IP values are determined on simulated hydrophobic tail （SHT） models. The obtained results reveal that the introduction of SHT approach permits the distinction between the polarities of different surfactants and their head groups. The measured polarity terms are discussed as related to hydrophile-lipophile balance （HLB） number and the hydrophobic group carbon number （RCn）. Some equations relating the measured polarity values and these variable have been developed.

关键词：气相色谱法含氮表面活性剂疏水尾链模型极性参数模拟测定

Comparison of Perovskite Systems Based on AFeo_(3)(A=Ce,La,Y)in Co_(2) Hydrogenation to Co

在线全文

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2024年第4期30卷 337-358页

作者： Anna n.Matveyeva Shamil o.omarov Laboratory of Materials and Processes for Hydrogen Energy Ioff e Institute194021 St.PetersburgRussia

Co_(2) is the most cost-eff ective and abundant carbon resource,while the reverse water-gas reaction(rWGS)is one of the most eff ective methods of Co_(2) *** work presents a comparative study of rWGS activity for perovskite systems based on AFeo_(3)(where A=Ce,La,Y).These systems were synthesized by solution combustion synthesis(SCS)with diff erent ratios of fuel(glycine)and oxidizer(φ),diff erent amounts of nH 4 no_(3),and the addition of alumina or silica as *** techniques,including X-ray diff raction analysis,thermogravimetric analysis,Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy,energy-dispersive X-ray spectroscopy,n 2-physisorption,H_(2) temper-ature-programmed reduction,temperature-programmed desorption of H_(2) and Co_(2),Raman spectroscopy,and in situ FTIR,were used to relate the physicochemical properties with the catalytic performance of the obtained *** specifi c perovskite-containing system(either bulk or supported)has its own optimalφand nH_(4) no_(3) amount to achieve the highest yield and dispersion of the perovskite *** all synthesized systems,bulk SCS-derived La-Fe-o systems showed the highest resistance to reducing environments and the easiest hydrogen desorption,outperforming La-Fe-o produced by solgel combustion(SGC).Co_(2) conversion into Co at 600°C for bulk ferrite systems,depending on the A-cation type and preparation method,follows the order La(SGC)nces in properties between La-Fe-o obtained by the SCS and SGC methods can be attributed to diff erent ratios of oxygen and lanthanum vacancy contributions,hydroxyl coverage,morphology,and free iron oxide *** situ FTIR data revealed that Co_(2) hydrogenation occurs through formates generated under reaction conditions on the bulk system based on La-Fe-o,obtained by the SCS method.γ-Al_(2)o_(3) improves the dispersion of CeFeo_(3) and LaFeo_(3) phases,the specifi c surface area,and the quant

关键词： Perovskites LaFeo_(3) CeFeo_(3) YFeo_(3) Solution combustion synthesis Co_(2) hydrogenation Reverse water–gas reaction(rWGS)

numerical Simulation of Thermocapillary Convection with Evaporation Induced by Boundary Heating

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第7期20卷 1667-1686页

作者： o.n.Goncharova V.B.Bekezhanova Altai State University Institute of Mathematics and Information TechnologiesBarnaul656049Russia Institute of Computational Modelling SB RAS Department of Differential Equations of MechanicsKrasnoyarsk660036Russia

The dynamics of a bilayer system filling a rectangular cuvette subjected to external heating is *** influence of two types of thermal exposure on the flow pattern and on the dynamic contact angle is *** particular,the cases of local heating from below and distributed thermal load from the lateral walls are *** simulation is carried out within the frame of a two-sided evaporative convection model based on the Boussinesq approximation.A benzine–air system is considered as reference *** variation in time of the contact angle is described for both heating *** lateral heating,near-wall boundary layers emerge together with strong convection,whereas the local thermal load from the lower wall results in the formation of multicellular motion in the entire volume of the fluids and the appearance of transition regimes followed by a steady-state *** results of the present study can aid the design of equipment for thermal coating or drying and the development of methods for the formation of patterns with required structure and morphology.

关键词： Thermocapillary convection two-phase system numerical modeling contact angle

Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria n.Poshina Aleksandra o.Sitnikova natalia n.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the Russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—oSo3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcoH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcoH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%nning electron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

Detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan

在线全文

学校读者我要写书评

暂无评论

Geodesy and Geodynamics 2024年第2期15卷 156-165页

作者： natalya V.Silacheva n.P.Stepanenko o.K.Kurilova A.D.Kudabayeva A.T.Danabayeva Institute of Seismology Ministry of Emergency SituationsAlmaty 050060Kazakhstan

Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the *** regulations are created on the basis of seismic zoning maps of various degrees of detail,developed by our Institute of Seismology using a new methodological approach for *** article is about creating the first normative map of the Detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan *** carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main provisions of Eurocode 8and updated compared with that used in developing maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of *** most thorough and current data accessible for the area under consideration were combined with contemporary analytical *** have been done to not only the databases being used but also the way seismic sources were shown,including active faults *** a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic *** obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s previous ***,because active faults were included and a thoroughly revised catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the *** the west of the territory,acceleration values also increased due to a more accurate consideration of seismotectonic *** maps are the basis for developing new state building regulations of the Republic of Kazakhstan.

关键词： Probabilistic seismic hazard assessment Detailed seismic zoning Peak ground acceleration Microseismical intensity

Machine learning in liver surgery:Benefits and pitfalls

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第12期12卷 2134-2137页

作者： Rafael Calleja Manuel Durán María Dolores Ayllón Ruben Ciria Javier Briceño Hepatobiliary Surgery and Liver Transplantation Unit Hospital Universitario Reina SofíaMaimonides Biomedical Research Institute of CordobaCórdoba 14004Spain

The application of machine learning(ML)algorithms in various fields of hepatology is an issue of ***,we must be cautious with the *** this letter,based on a published ML prediction model for acute kidney injury after liver surgery,we discuss some limitations of ML models and how they may be addressed in the *** the future faces significant challenges,it also holds a great potential.

关键词： Machine learning Liver surgery Artificial intelligence Random forest Prediction model

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt M.Gyrdymov S.Zähter P.Tavana M.M.Günther n.Bukharskii n.Borisenko J.Jacoby X.F.Shen A.Pukhov n.E.Andreev o.n.Rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany national Research nuclear University MEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation Moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

nano Materials Science 2024年第2期6卷 193-200页

作者： M.I.Ikim G.n.Gerasimov V.F.Gromov o.J.Ilegbusi L.I.Trakhtenberg n.n.Semenov Federal Research Center for Chemical Physics of RAS MoscowRussia University of Central Florida OrlandoFLUSA Moscow Institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow State University MoscowRussia

The hydrothermal synthesis of In_(2)o_(3)and Ceo_(2)–In_(2)o_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)o_(3),intermediate products In(oH)_(3)and InooH are formed,which are the precursors of stable cubic(c-In_(2)o_(3))and metastable rhombohedral(rh-In_(2)o_(3))phases,respectively.A transition from c-In_(2)o_(3)to rh-In_(2)o_(3)is observed with the addition of Ceo_(2).The introduction of cerium into rh-In_(2)o_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)o_(3).The data on the sensor activity of the composites correlate with XPS results in which Ceo_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)o_(3).The reverse situation is observed in composites based on c-In_(2)o_(3).Compared to In_(2)o_(3)and Ceo_(2)–In_(2)o_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)o_(3)and Ceo_(2).

关键词： Cerium oxide Indium oxide nanocomposite Hydrothermal method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2024年第9期19卷 2068-2074页

作者： Carolina Aguado Sara Badesso JoséMartínez-Hernández Alejandro Martín-Belmonte Rocío Alfaro-Ruiz Miriam Fernández Ana Esther Moreno-Martínez Mar Cuadrado-Tejedor Ana García-osta Rafael Luján Synaptic Structure Laboratory Instituto de Investigación en Discapacidades Neurológicas(IDINE)Department of Medical SciencesFacultad de MedicinaUniversidad de Castilla-La ManchaCampus BiosanitarioAlbaceteSpain Gene Therapy for neurological Disease Program Center for Applied Medical Research(CIMA)University of NavarraInstituto de Investigación Sanitaria de Navarra(IdiSNA)PamplonaSpain Pharmacology Unit Department of Pathology and Experimental TherapeuticsFaculty of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaBarcelonaSpain neuropharmacology and Pain Group Neuroscience ProgramInstitut d’InvestigacióBiomèdica de BellvitgeIDIBELLL’Hospitalet de LlobregatSpain Department of Pathology Anatomy and PhysiologySchool of MedicineUniversity of NavarraPamplonaSpain UniversitéGrenoble Alpes Grenoble Institut des NeurosciencesGrenobleFrance

Plaques of amyloid-β(Aβ)and neurofibrillary tangles are the main pathological characteristics of Alzheimer’s disease(AD).However,some older adult people with AD pathological hallmarks can retain cognitive *** the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic *** hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels,which may underlie healthy cognitive performance in aged AD *** the Morris Water Maze test,we selected resilient(asymptomatic)and cognitively impaired aged Tg2576 *** the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups,western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant *** further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice,we employed stereological and electron microscopic *** findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic ***,through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice,we uncovered differences in the subcellular localization of glutamate ***,the density of GluA1,GluA2/3,and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic ***,the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic *** subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play cr

关键词： aging Alzheimer´s disease cognitive hippocampus immunoelectron microscopy resilience synapse

From BIM model to 3D construction printing:A framework proposal

在线全文

学校读者我要写书评

暂无评论

Frontiers of Architectural Research 2024年第4期13卷 912-927页

作者： Rodrigo García-Alvarado Pedro Soza Ginnia Moroni Fernando Pedreros Martín Avendaño Pablo Banda Cristian Berríos Depto.Diseño y Teoría de La Arquitectura Universidad Del Bío-BíoConcepciónChile Depto.Arquitectura Universidad de ChileSantiagoChile Facultad de Ingeniería Arquitectura y DiseñoUniversidad San SebastiánConcepciónChile Facultad de Arquitectura Arte y DiseñoUniversidad Diego PortalesSantiagoChile

The growth of 3D construction printing needs appropriate integration into the planning and execution phases of building *** this aim,the Architecture,Engineering,and Construction sector(AEC)has been increasingly adopting building information modeling(BIM)systems to synchronize design and construction *** study proposes a technical workflow to manage 3D construction printing into BIM models,evaluating various procedures according to construction element *** on mature software platforms,the research details the data transfer process using a case study of a single-story *** case delves into design procedures for constructing walls of varied shapes,adjustments in width,joints,openings,textures,fillings,and the insertion of reinforcements and services while also discussing requirements of other building *** steps for managing design information and controlling printing machines are *** study’s outcome presents a comprehensive information flow,encompassing model segmentation,geometric data transfer,adjustments of details,and the generation of printing ***,it is offered a discussion that underlines the importance of a synergistic digital information flow that merges both design and execution phases,promoting construction efficiency and the embrace of innovative *** contribution of the paper focuses on technical design strategies for 3D construction printing,but also on suggesting an integrated process.

关键词： 3D construction printing Additive manufacturing Architectural design BIM