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Novel eco-effi.i.nt reacti.e di.ti.lati.n process for di.ethyl carbonate producti.n by i.di.ect alcoholysi. of urea

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Fronti.rs of Chemi.al Sci.nce and Engi.eeri.g 2022年第2期16卷 316-331页

作者： i.li.n Patrașcu Costi. S.Bîldea Anton A.Ki.s Department of Chemi.al and Bi.chemi.al Engi.eeri.g University“Politehnica”of Bucharest011061 BucharestRomania Department of Chemi.al Engi.eeri.g and Analyti.al Sci.nce The University of ManchesterManchester M139PLUK

Di.ethyl carbonate i. an eco-fri.ndly essenti.l chemi.al that can be sustai.ably produced from CO_(2),whi.h i. avai.able from carbon capture acti.i.i.s or can even be captured from the *** rapi. i.crease i. di.ethyl carbonate demand i. dri.en by the fast growth of polycarbonates,solvent,pharmaceuti.al,and li.hi.m-i.n battery *** carbonate can be produced from CO_(2)through vari.us chemi.al pathways,but the most conveni.nt route reported i. the i.di.ect alcoholysi. of *** research used techni.ues such as heat i.tegrati.n and reacti.e di.ti.lati.n to reduce the energy use and costs,but the use of an excess of methanol i. the trans-esteri.i.ati.n step led to an energy i.tensi.e extracti.e di.ti.lati.n requi.ed to break the di.ethyl carbonate-methanol *** work shows that the producti.n of di.ethyl carbonate by i.di.ect alcoholysi. of urea can be i.proved by usi.g an excess of propylene carbonate(i.stead of an excess of methanol),a neat feat that we showed i. requi.es only 2.64 kW·h·kg^(-1) di.ethyl carbonate i. a reacti.n-separati.n-recycle process,and a reacti.e di.ti.lati.n column that effecti.ely replaces two conventi.nal di.ti.lati.n columns and the reactor for di.ethyl carbonate ***,less equi.ment i. requi.ed,the methanol-di.ethyl carbonate azeotrope does not need to be recycled,and the overall savi.gs are ***,we propose the use of a reacti.e di.ti.lati.n column i. a heat i.tegrated process to obtai. hi.h puri.y di.ethyl carbonate(>99.8 wt-%).The energy requi.ement i. reduced by heat i.tegrati.n to just 1.25 kW·h·kg^(-1) di.ethyl carbonate,whi.h i. about 52%lower than the reacti.n-separati.n-recycle *** benefi. from the energy savi.gs,the dynami.s and control of the process are provi.ed for10%changes i. the nomi.al rate of 32 ktpy di.ethyl carbonate,and for uncertai.ti.s i. reacti.n ki.eti.s.

关键词： di.ethyl carbonate reacti.e di.ti.lati.n process desi.n plantwi.e control

i.pact of Drai. Effluent on Surfi.i.l Sedi.ents i. the Medi.erranean Coastal Wetland: Sedi.entologi.al Characteri.ti.s and Metal Polluti.n Status at Lake Manzala, Egypt

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Journal of Ocean Uni.ersi.y of Chi.a 2019年第4期18卷 834-848页

作者： FARHAT Hassan i. Geology Department Faculty of Science Suez University

Surface sedi.ents were collected from Lake Manzala, the Medi.erranean coastal wetland located to the east of the Ni.e Delta, Egypt, to assess the effect of drai. effluent on the spati.l vari.ti.ns of sedi.entary characteri.ti.s and heavy metal polluti.n. Grai.-si.e composi.i.ns, textures, and heavy metal di.tri.uti.n patterns i. sedi.ents are presented usi.g Gi. techni.ue. Results of the analysi. of the sedi.ent showed a clear effect of drai. effluent, wi.h an i.crease i. fi.e fracti.ns and homogeneous suspensi.ns i. transportati.n mode. Lake sedi.ents were domi.ated by sandy mud textures, and mode of transportati.n was homogeneous sus- pensi.n and rolli.g. Spati.l di.tri.uti.n of heavy metals (Fe, Mn, Zn, cu, Ni. Cr, and Pb) was studi.d i. the lake’s surfi.i.l sedi.ents, along wi.h thei. relati.nshi. to drai. effluent and thei. contami.ati.n status i. the ecologi.al system. Heavy metal polluti.n status was assessed by means of accepted sedi.ent quali.y gui.eli.es and contami.ati.n assessment methods (contami.ati.n factor, con- tami.ati.n degree, modi.i.d contami.ati.n degree, geo-accumulati.n, and enri.hment factor). Among the determi.ed heavy metals, Pb had the most ecologi.al ri.k. Generally, the heavy metals i. the surface sedi.ents i.di.ated polluti.n ri.k rangi.g from moderate to consi.erable, parti.0}larly, i. those si.es faci.g drai.s and i.lets that had the hi.hest toxi. effluent. The results were i.terpreted by stati.ti.al means. A cluster analysi. defi.ed areas faci.g drai. di.charge and i.lets as separated groups. ANOVA i.di.ated that most of the sedi.entati.n and studi.d metals di.ected thi. clusteri.g.

关键词： Lake Manzala Medi.erranean wetland metal polluti.n sedi.entologi.al characteri.ti.s

Exact orbi.al-free ki.eti. energy functi.nal for general many-electron systems

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Fronti.rs of physi.s 2020年第2期15卷 87-92页

作者： Thomas pope Werner Hofer School of Natural and Envi.onmental Sci.nces Newcastle UniversityNewcastle NE17RUUnited Kingdom School of Physi.al Sci.nces University of Chinese Academy of SciencesBeijing 100190China

The exact form of the ki.eti. energy functi.nal has remai.ed elusi.e i. orbi.al-free models of densi.y functi.nal theory(DFT).Thi. has been the mai. stumbli.g block for the development of a general-purpose framework on thi. ***,we show that on the basi. of a two-densi.y model,whi.h represents many-electron systems by mass densi.y and spi. densi.y components,we can deri.e the exact form of such a *** exact functi.nal i. shown to contai. previ.usly suggested functi.nals to some extent,wi.h the notable excepti.n of the Thomas-Fermi.ki.eti. energy functi.nal.

关键词： condensed matter densi.y functi.nal theory(DFT) extended electrons

A two-densi.y approach to the general many-body problem and a proof of pri.ci.le for small atoms and molecules

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Fronti.rs of physi.s 2019年第2期14卷 89-96页

作者： Thomas pope Werner Hofer School of Natural and Envi.onmental Sci.nces Newcastle UniversityNewcastle NE1 7RUUnited Kingdom i.sti.ute of Physi.s & Uni.ersi.y of Chi.ese Academy of Sci.nces Chinese Academy of SciencesBeijing 100190China

An extended electron model fully recovers many of the experi.ental results of quantum mechani.s whi.e i. avoi.s many of the pi.falls and remai.s generally free of paradoxes. The formulati.n of the manybody electroni. problem here resembles the Kohn Sham formulati.n of standard densi.y functi.nal theory. However, rather than referri.g electroni. properti.s to a large set of si.gle electron orbi.als, the extended electron model uses only mass densi.y and fi.ld components, leadi.g to a substanti.l i.crease i. computati.nal effi.i.ncy. To date, the Hohenberg-Kohn theorems have not been proved for a model of thi. type, nor has a uni.ersal energy functi.nal been presented. i. thi. paper, we address these problems and show that the Hohenberg Kohn theorems do also hold for a densi.y model of thi. type. We then present a proof^of^concept practi.al i.plementati.n of thi. method and show that i. reproduces the accuracy of more wi.ely used methods on a test-set of small atomi. systems, thus pavi.g the way for the development of fast, effi.i.nt and accurate codes on thi. basi..

关键词： many-body condensed matter Hartree-Fock densi.y functi.nal theory extended electrons

Spi. i. the extended electron model

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Fronti.rs of physi.s 2017年第3期12卷 81-85页

作者： Thomas pope Werner Hofer School of Chemi.try Newcastle University Newcastle NE1 7RU UK

i. has been found that a model of extended electrons i. more sui.ed to descri.e theoreti.al si.ula- ti.ns and experi.ental results obtai.ed vi. scanni.g tunnelli.g mi.roscopes, but whi.e the dynami. properti.s are easi.y i.corporated, magneti. properti.s, and i. parti.0}lar electron spi. properti.s pose a problem due to thei. concei.ed i.otropy i. the absence of measurement. The spi. of an electron reacts wi.h a magneti. fi.ld and thus has the properti.s of a vector. However, electron spi. i. also i.otropi., suggesti.g that i. does not have the properti.s of a vector. Thi. central confli.t i. the de- scri.ti.n of an electron＇s spi., we beli.ve, i. the root of many of the paradoxi.al properti.s measured and postulated for quantum spi. parti.les. Exploi.i.g a model i. whi.h the electron spi. i. descri.ed consi.tently i. real three-di.ensi.nal space - an extended electron model - we demonstrate that spi. may be descri.ed by a vector and sti.l mai.tai. i.s i.otropy. i. thi. framework, we re-evaluate the Stern-Gerlach experi.ents, the Ei.stei.-Podolsky-Rosen experi.ents, and the effect of consecuti.e ts and fi.d i. all cases a fai.ly i.tui.i.e explanati.n.

关键词： spi. extended electron model geometri. algebra Stern-Gerlach experi.ent Ei.stei.-Podolsky-Rosen magneti.m

Growth of large-area ali.ned pentagonal graphene domai.s on hi.h-i.dex copper surfaces

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Nano Research 2016年第7期9卷 2182-2189页

作者： Kai.un Xi. Vasi.i. i. Artyukhov Li.ei.Sun Ji.gyi.g Zheng Li.i.g Ji.o Bori. i. Yakobson Yi.gyi.g Zhang Department of Chemi.try Tsinghua University Beijing 100084 China Center for Nano and Mi.ro Mechani.s Tsinghua University Beijing 100084 China Department of Materi.ls Sci.nce and Nano Engi.eeri.g Rice University Houston TX 77005 USA

Si.gle-crystal graphene domai.s grown by chemi.al vapor deposi.i.n （CVD） i.tri.si.ally tend to have a si.-fold symmetry; however, several factors can i.fluence the growth ki.eti.s, whi.h can i. turn lead to the formati.n of graphene wi.h di.ferent shapes. Here we report the growth of ori.nted large-area pentagonal si.gle-crystal graphene domai.s on cu foi.s by CVD. We found that hi.h-i.dex cu planes contri.uted selecti.ely to the formati.n of pentagonal graphene. Our results i.di.ated that latti.e steps present on the crystalli.e surface of the underlyi.g cu promoted graphene growth i. the di.ecti.n perpendi.0}lar to the steps and fi.ally led to the di.appearance of one of the edges formi.g a pentagon. i. addi.i.n, hydrogen promoted the formati.n of pentagonal domai.s. Thi. work provi.es new i.si.hts i.to the mechani.m of graphene growth.

关键词： pentagonal graphene copper foi. hi.h i.dex plane chemi.al vapor deposi.i.n large area

Preparati.n of a New Polyoxometalate-based Nanoparti.les

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Chi.ese Chemi.al Letters 2004年第6期15卷 714-716页

作者： Xi.oHongWANG FengLi.Ji.gFuLi. M.T.pope DepartmentofChemi.try NortheastNormalUniversityChangchtm130024 DepartmentofChemi.try GeorgetownUniversityWashingtonDC20057-1227U.S.A

Polyoxometalates (POMs) α-K8 H6 [Si.W18Ti.O77] (Si.W18Ti.) loaded starch nanop-arti.les have been prepared and structurally characteri.ed by elemental analyses, i. spectra and 29Si.spectroscopy. The parti.le si.e of Si.W18Ti. /starch was esti.ated by a Transmi.si.n electron mi.roscope (TEM) and a 1000HSA MALVi.N Zetasi.er i.strument. The result shows that the polyoxometalate retai.ed the parent structure after encapsulated by starch mi.rospheres.

关键词： Polyoxometalate nanoparti.le synthesi..

Hydrocele of the canal of Nuck—an old problem revi.i.ed

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Fronti.rs of Medi.i.e 2013年第4期7卷 517-519页

作者： John Bunni.Mark Gi.lam i.n Mi.hael pope Department of General Surgery Bristol Royal InfirmaryBristol BS28HWUK

Herei. the authors descri.e the case of a young woman presenti.g wi.h a tender lump i. her *** the di.ferenti.l was of ei.her a reacti.e lymph node or a femoral *** scan was urgently arranged and showed a cysti. *** explorati.n was carri.d out and revealed thi. to be a hydrocele of the canal of *** was exci.ed and the pati.nt’s symptoms resolved and she was di.charged home the followi.g *** explore the embryology,pathophysi.logy and management of thi. rare enti.y.

关键词： canal of Nuck herni. embryology

Freestandi.g MoSe_(2)nanoflowers for superi.r Li.Na storage properti.s

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Tungsten 2024年第1期6卷 238-247页

作者： Qi.o cu Chao-Qun Shang Guo-Fu Zhou Xi. Wang Guangdong Provi.ci.l Key Laboratory of Opti.al i.formati.n Materi.ls South China Normal UniversityGuangzhou 510006China School of Materi.ls Sci.nce and Engi.eeri.g and Hubei.Key Laboratory of Plasma Chemi.try and Advanced Materi.ls Wuhan Institute of TechnologyWuhan 430205China i.ternati.nal Academy of Optoelectroni.s at Zhaoqi.g South China Normal UniversityZhaoqing 526060China

MoSe_(2),wi.h hi.h theoreti.al speci.i. capaci.y,has attracted a lot of *** remai.s an open challenge to effecti.ely suppress the i.reversi.le seleni.m di.soluti.n and rapi. capaci.y decrease i.duced by severe volume change duri.g ***,we synthesi.e MoSe_(2)nanoflowers di.persed on one-di.ensi.nal(1D)N-doped carbon nanofi.ers(MoSe_(2)@NCNFs)for use as a freestandi.g *** thi. uni.ue structure,the 1D N-doped carbon nanofi.ers are found to not only enhance the conducti.i.y but also ensure the structural i.tegri.y duri.g the Li.(+)/Na^(+)i.serti.n/destracti.n *** expected,at 2 A·g^(-1),the speci.i. capaci.y of the MoSe_(2)@NCNFs i. mai.tai.ed at 180 mAh·g^(-1)after 500 cycles when used i. li.hi.m storage ***,i. the case of sodi.m storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capaci.y of 122mAh·g^(-1)after 500 *** fi.di.gs suggest that the MoSe_(2)@NCNF electrodes may be a promi.i.g candi.ate for use i. reversi.le Li.Na storage appli.ati.ns.

关键词： Li.Na storage Freestandi.g electrode MoSe_(2) Electrochemi.al reacti.n ki.eti.s Structural i.tegri.y