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Effect of SiO_(2)on loss of catalysis of inherent metallic species in CO_(2)gasification of coke from lignite

Carbon Resources Conversion 2019年第1期2卷 13-22页

作者： Cheolyong Choi u.p.m.ashik Shinji Kudo Kazuya uebo Koyo Norinaga Jun-ichiro Hayashi Interdisciplinary Graduate School of Engineering Sciences Kyushu University6-1Kasuga KoenKasuga 816-8580Japan Institute for materials Chemistry and Engineering Kyushu University6-1Kasuga KoenKasuga 816-8580Japan process Research Laboratories Nippon Steel&Sumitomo Metal Corporation20-1ShintomiFuttsu 293-8511Japan Department of materials Science and Engineering School of EngineeringNagoya UniversityNagoyaAichi 464-8601Japan Transdisciplinary Research and Education Center of Green Technology Kyushu University6-1Kasuga KoenKasuga 816-8580Japan

Inherent metallic species retained by coal char or coke,such as Na and Ca,behave as catalysts in gasification.The char/coke normally contains inherent SiO_(2),which can react with the inherent catalysts to form silicates,resulting in catalyst deactivation over the range of pyrolysis,carbonization and gasification,and thereby reducing the char/coke reactivity.The present authors simulated the inherent catalyst deactivation experimentally by blending a Victorian lignite with SiO_(2),briquetting the SiO_(2)/lignite blend,carbonizing the briquette,and then gasifying the coke with CO_(2).The kinetic analysis of the gasification employed a comprehensive model,which assumed progress in parallel of non-catalytic and catalytic gasification.The model quantitatively described the measured kinetics of the coke gasification with different SiO_(2)contents over a range of coke conversion up to 99.9%.The kinetic analysis revealed that the SiO_(2)deactivated substantial and entire portions of the most active catalyst and its precursor,respectively,before the gasification(i.e.,during the carbonization).The catalyst deactivation also occurred during the gasification,but mainly following a self-deactivation mechanism that involved no silicates formation.

关键词： Coke Lignite Reactivity CO_(2)gasification Inherent metallic species Catalyst Deactivation SiO_(2)

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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese physics B 2024年第2期33卷 108-114页

作者： u.S.mahabaleshwar G.p.Vanitha L.m.pérez Emad H.Aly I.pop Department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked sheet.With the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is illustrated.The resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity transformations.The transformed differential equations are solved analytically.Impacts of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted graphically.The skin friction and Nusselt number were also evaluated.In addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching one.Further,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O nanofluid.Furthermore,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & molecular Immunology 2024年第2期21卷 103-118页

作者： S.Cankat m.u.Demael L.Swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent history.In this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus family.We will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2,mERS-CoV and the four seasonal coronaviruses(HCoV-OC43,NL63,HKu1 and 229E)in humans and the potential for future zoonotic coronaviruses.We will highlight how first-generation SARS-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine design.We will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer cross-protection.Finally,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection universal

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Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

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marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.p.Nagahawatta N.m.Liyanage Thilina u.Jayawardena H.H.A.C.K.Jayawardhana Seong‑Hun Jeong Hyung‑Jun Kwon You‑Jin Jeon Department of marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ferocity.SARS-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World Health Organization.Therefore,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently required.Numerous naturally occurring bioactive substances have been studied in the clinical setting for diverse disorders.The intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic compounds.marine natural products(mNps)have received increased attention in the development of novel drugs owing to their high diversity and availability.Therefore,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and structure.Furthermore,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing mNps and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 marine natural products Drug targets Inhibitors

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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and planetary physics 2024年第1期8卷 70-88页

作者： m.Grandin H.K.Connor S.Hoilijoki m.Battarbee Y.pfau-Kempf u.Ganse K.papadakis m.palmroth Department of physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight Center GreenbeltMD20771USA Space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The Solar wind magnetosphere Ionosphere Link Explorer(SmILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by SmILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SmILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can resu

关键词： magnetosphere magnetosheath numerical simulation SmILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Champika Bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.m.p.Singhakumara Xiangcheng mi I.A.u.N.Gunatilleke C.V.S.Gunatilleke mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(mDF),the dominant rain forest type in tropical wet equatorial Asia.In our study,we sought to document such trends over forty years across three sites representing lowland to lower montane elevations.methods:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth forest.We measured trees for diameter at breast height that we identified to species and tagged.We took wood samples to calculate species wood-specific gravity.We re-measured plots in 1998 and again in 2018.Results:We show standing AGB for all sites combined to be 517.52 mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the same.Relatively few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year sampled.One species,mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation site.Conclusions:Our results are directly relevant to estimating AGB and standing carbon sequestered in mDF.Our study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in mDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

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Fuzzy and IRLNC-based routing approach to improve data storage and system reliability in IoT

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Intelligent and Converged Networks 2024年第1期5卷 68-80页

作者： u.Indumathi A.R.Arunachalam the Department of Computer Science and Engineering Dr.M.G.R.Educational and Research InstituteChennai 600095India

Internet of Things(IoT)based sensor network is largely utilized in various field for transmitting huge amount of data due to their ease and cheaper installation.While performing this entire process,there is a high possibility for data corruption in the mid of transmission.On the other hand,the network performance is also affected due to various attacks.To address these issues,an efficient algorithm that jointly offers improved data storage and reliable routing is proposed.Initially,after the deployment of sensor nodes,the election of the storage node is achieved based on a fuzzy expert system.Improved Random Linear Network Coding(IRLNC)is used to create an encoded packet.This encoded packet from the source and neighboring nodes is transmitted to the storage node.Finally,to transmit the encoded packet from the storage node to the destination shortest path is found using the Destination Sequenced Distance Vector(DSDV)algorithm.Experimental analysis of the proposed work is carried out by evaluating some of the statistical metrics.Average residual energy,packet delivery ratio,compression ratio and storage time achieved for the proposed work are 8.8%,0.92%,0.82%,and 69 s.Based on this analysis,it is revealed that better data storage system and system reliability is attained using this proposed work.

关键词： Internet of Things(IoT) data storage management fuzzy system improved random linear network coding energy utilization system reliability

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predictive factors for percutaneous nephrolithotomy bleeding risks

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Asian Journal of urology 2024年第1期11卷 105-109页

作者： u phun Loo Chun Hou Yong Guan Chou Teh urology Department Sarawak General HospitalKuchingMalaysia

Objective:This study aimed to identify predictive factors for percutaneous nephrolithotomy(pCNL)bleeding risks.With better risk stratification,bleeding in high-risk patient can be anticipated and facilitates early identification.methods:A prospective observational study of pCNL performed at our institution was done.All adults with radio-opaque renal stones planned for pCNL were included except those with coagulopathy,planned for additional procedures.Factors including gender,co-morbidities,body mass index,stone burden,puncture site,tract dilatation size,operative position,surgeon's seniority,and operative duration were studied using stepwise multivariate regression analysis to identify the predictive factors associated with higher estimated hemoglobin(Hb)deficiency.Results:Overall,4.86%patients(n=7)received packed cells transfusion.The mean estimated Hb deficiency was 1.3(range 0-6.5)g/dL and the median was 1.0 g/dL.Stepwise multivariate regression analysis revealed that absence of hypertension(p=0.024),puncture site(p=0.027),and operative duration(p=0.023)were significantly associated with higher estimated Hb deficiency.However,the effect sizes are rather small with partial eta-squared of 0.037,0.066,and 0.038,respectively.Observed power obtained was 0.621,0.722,and 0.625,respectively.Other factors studied did not correlate with Hb difference.Conclusion:Hypertension,puncture site,and operative duration have significant impact on estimated Hb deficiency during pCNL.However,the effect size is rather small despite adequate study power obtained.Nonetheless,operative position(supine or prone),puncture number,or tract dilatation size did not correlate with Hb difference.The mainstay of reducing bleeding in pCNL is still meticulous operative technique.Our study findings also suggest that pCNL can be safely done by urology trainees under supervision in suitably selected patient,without increasing risk of bleeding.

关键词： percutaneous nephrolithotomy predictive factor Risk factor Bleeding Blood loss

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Lump and travelling wave solutions of a(3+1)-dimensional nonlinear evolution equation

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Journal of Ocean Engineering and Science 2024年第2期9卷 164-172页

作者： Kalim u.Tariq Raja Nadir Tufail Department of mathematics Mirpur University of Science and TechnologyMirpurAJK 10250Pakistan

In this paper,the(3+1)-dimensional nonlinear evolution equation is studied analytically.The bilinear form of given model is achieved by using the Hirota bilinear method.As a result,the lump waves and col-lisions between lumps and periodic waves,the collision among lump wave and single,double-kink soliton solutions as well as the collision between lump,periodic,and single,double-kink soliton solutions for the given model are constructed.Furthermore,some new traveling wave solutions are developed by applying the exp(−φ(ξ))expansion method.The 3D,2D and contours plots are drawn to demonstrate the nature of the nonlinear model for setting appropriate set of parameters.As a result,a collection of bright,dark,periodic,rational function and elliptic function solutions are established.The applied strategies appear to be more powerful and efficient approaches to construct some new traveling wave structures for various contemporary models of recent era.

关键词： The Hirota bilinear method Lump wave solution Travelling wave solution Exp(−φ(ξ))expansion technique

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Development of immature ovarian teratoma after mature teratoma in a girl with familial ovarian teratoma:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1442-1447页

作者： u Chul Ju Woo Dae Kang Seok mo Kim Department of Obstetrics and Gynecology Chonnam National University Medical SchoolGwangju 61469South Korea

BACKGROuND Immature ovarian teratoma is a rare and aggressive neoplasm that affects young women.This report is the first to describe the development of immature teratoma after ovarian cystectomy for mature teratoma of the ovary in an adolescent female with a family history of ovarian teratoma.CASE SummARY A 16-year-old girl who had undergone bilateral ovarian cystectomy for mature teratomas 3 years ago showed bilateral adnexal tumors during her regular ultrasonography follow-up every 6 months.She received laparoscopic bilateral ovarian cystectomy,and final histopathology showed grade-1 immature teratoma of the left ovary and mature teratoma of the right ovary.Laparoscopic left salpingo-oophorectomy and staging procedures were performed again.Her mother,maternal aunt,and maternal grandmother had also received surgeries for mature ovarian teratomas.CONCLuSION It is important to have guidance on management of patient and family members with familial ovarian teratomas.

关键词： Familial ovarian teratomas Adolescent female Immature ovarian teratoma management Case report

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