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Long-term Integration Ability of.the Submillimeter Wave Astronomy Satellite(SWAS)Spectral Line Receivers

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Research in Astronomy and Astrophysics 2024年第6期24卷 315-322页

作者： Bing-Ru Wang Di Li Paul f.Goldsmith Jingwen Wu Chao-Wei Tsai Rudolf.Schieder Gary J.Melnick National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of.Chinese Academy of.Sciences Beijing 100049China Research Center f.r Astronomical Computing Zhejiang LaboratoryHangzhou 311100China Jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Institute f.r f.ontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China KOSMA I.Physik.InstitutUniversität zu KölnZülpicher Str.7750937 KölnGermany Center f.r Astrophysics|Harvard&Smithsonian 60 Garden StreetMS 66CambridgeMA 02138USA

The Submillimeter Wave Astronomy Satellite(SWAS)was the f.rst space telescope capable of.high spectral resolution observations of.terahertz spectral *** have investigated the integration ability of.its two receivers and spectrometer during f.ve and a half.years of.on-orbit *** CI,O_(2),H_(2)O,and^(13)CO spectra taken toward all observed Galactic sources were *** present results are based on spectra with a total integration time of.up to 2.72×10~4hr(■10~8s).The noise in the spectra is generally consistent with that expected f.om the radiometer equation,without any sign of.approaching a noise *** noise perf.rmance ref.ects the extremely stable perf.rmance of.the passively cooled f.ont end as well as other relevant components in the SWAS instrument throughout its mission lif.time.

关键词： telescopes space vehicles:instruments instrumentation:miscellaneous ISM:lines and bands

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In situ digital testing method f.r quality assessment of.sof. soil improvement with polyurethane

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Journal of.Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.f.Wang C.J.Wang W.V.Yue Z.J.Zhang Z.Q.Yue Department of.Civil Engineering China University of Geosciences (Beijing)BeijingChina Department of.Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of.Geotechnical Engineering Tongji UniversityShanghaiChina Department of.Civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of.soil *** drilling data includes the spatial distribution and in situ strength of.untreated and treated soil along three dif.erent drillholes measured by on-site drilling monitoring *** f.ctual drilling data can characterize the degree of.soil improvement by penetration injection with permeable *** f.om on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of.drill bit advancement *** drilling time,which indicates the spatial distributions of.soil *** soil prof.le at the study site is composed of.f.ur layers,which includes f.ll,untreated silty clay,treated silty clay,and mucky *** results of.soil prof.le are verif.ed by the parallel site *** constant drilling speeds prof.le the coring-resistant strength of.drilled *** comparing with the untreated silty clay,the constant drilling speeds of.the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of.61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of.treated silty *** tests,*** compressive strength(UCS)test,have been perf.rmed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of.treated silty clay are 2.4-6.9 times higher than the average measured strength of.untreated silty *** UCS-based indices of.374.5%and 344.2%verif.ed the quality assessment(QA)results by this new in situ *** method provides a cost-ef.ective tool f.r quality assessment of.soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement Quality assessment

MgO-attached graphene nanosheet(MgO@GNS)reinf.rced magnesium matrix nanocomposite with superior mechanical,corrosion and biological perf.rmance

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International Journal of.Minerals,Metallurgy and Materials 2024年第9期31卷 2062-2076页

作者： S.Abazari A.Shamsipur H.R.Bakhsheshi-Rad M.S.Soheilirad f.Khorashadizade S.S.Mirhosseini Department of.Materials and Metallurgical Engineering Amirkabir University of TechnologyTehran ***Iran Iranian National Standards Organization of.Hormozgan HormozganIran Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Department of.Materials and Metallurgical Engineering Iran University of Science and TechnologyTehranIran

Magnesium(Mg)alloys are gaining great consideration as body implant materials due to their high biodegradability and ***,they suf.er f.om low corrosion resistance and antibacterial *** this research,semi-powder metallurgy f.llowed by hot extrusion was utilized to produce the magnesium oxide@graphene nanosheets/magnesium(MgO@GNS/Mg)composite to improve mechanical,corrosion and cytocompatibility *** have revealed that the incorporation of.MgO@GNS nanohybrids into Mg-based composite enhanced microhardness and compressive *** vitro,osteoblast cell culture tests show that using MgO@GNS nanohybrid f.llers enhances osteoblast adhesion and apatite *** presence of.MgO@GNS nanoparticles in the composites decreased the opening def.cts,micro-cracks and micro-pores of.the composites thus preventing the penetration of.the corrosive solution into the *** demonstrated that the MgO@GNS/Mg composite possesses excellent antibacterial properties because of.the combination of.the release of.MgO and physical damage to bacterium membranes caused by the sharp edges of.graphene nanosheets that can ef.ectively damage the cell wall thereby f.cilitating penetration into the bacterial lipid ***,the MgO@GNS/Mg composite with high mechanical strength,antibacterial activity and corrosion resistance is considered to be a promising material f.r load-bearing implant applications.

关键词： metal matrix composites MgO@GNS nanohybrid strengthening mechanisms antibacterial activity biocompatibility

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

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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 f.deral Research Center f.r Chemical Physics of.RAS MoscowRussia University of.Central f.orida 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 f.rmed,which are the precursors of.stable cubic(c-In_(2)O_(3))and metastable rhombohedral(rh-In_(2)O_(3))phases,respectively.A transition f.om 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 f.r the dependence of.sensitivity on the direction of.electron transf.r 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

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SARS-CoV-2 variants are associated with dif.erent clinical courses in children with MIS-C

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World Journal of.Pediatrics 2024年第2期20卷 143-152页

作者： Andres f.Moreno Rojas Emelia Bainto Helen Harvey Adriana H.Tremoulet Jane C.Burns Kirsten B.Dummer Department of.Pediatrics Division of Pediatric CardiologyUniversity of California San Diegoand Rady Children’s Hospital3020 Children’s Way MC 5004San DiegoCA 92123USA Kawasaki Disease Research Center La JollaCAUSA Department of.Pediatrics Division of Pediatric Critical CareUniversity of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA Department of.Pediatrics University of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA

Background Recent inf.ction with SARS‑CoV-2 in children has been associated with multisystem inf.ammatory syndrome in children(MIS-C).SARS‑CoV-2 has undergone dif.erent *** publications exist about specif.c variants and their correlation with the severity of.*** This was a single-center,retrospective study including all patients admitted with MIS-C at Rady Children’s Hospital-San Diego between May 2020 and March *** epidemiologic data,including viral genomic inf.rmation,were obtained f.om public ***,clinical presentation,laboratory values,and outcomes were obtained f.om electronic medical *** The analysis included 104 pediatric *** MIS-C waves were *** variants in San Diego during the f.rst wave included clades 20A to *** the second wave,there were variants f.om clades 20A to C,20G,21C(Epsilon),20I(Alpha),and 20J(Gamma).The third wave had Delta strains(clades 21A,21I,and 21J),and the f.urth had Omicron variants(clades 21K,21L,and 22C).MIS-C presented with similar symptoms and laboratory f.ndings across all *** patients were admitted to the pediatric intensive care unit(PICU)(74%)and required inotropic support(63%)during the second *** of.the patients required mechanical circulatory support,and only two required invasive ventilatory *** was no *** The various strains of.SARS-CoV-2 triggered MIS-C with dif.ering severities,with the second wave having a more severe clinical *** the dif.erences in disease severity across variants were due to changes in the virus or other f.ctors remains unknown.

关键词： Complications COVID-19 MIS-C SARS-CoV-2 variants

Prospective cohort study on f.cial prof.le changes in inf.nts with Robin sequence and healthy controls

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World Journal of.Pediatrics 2024年第6期20卷 581-589页

作者： Cornelia Wiechers Julian Sowula Karen Kreutzer Christoph E.Schwarz Christina Weismann Michael Krimmel Christian f.Poets Bernd Koos Department of.Neonatology Tuebingen University HospitalCalwerstrasse 772076 TuebingenGermany Center f.r Clef. Lip Palate and Craniofacial MalformationsTuebingen University HospitalTuebingenGermany Department of.Orthodontics Tuebingen University HospitalTuebingenGermany Department of.Oral and Maxillof.cial Surgery Tuebingen University HospitalTuebingenGermany

Background Various conservative and surgical approaches exist to treat Robin sequence(RS),but their ef.ects on f.cial prof.le and mandibular catch-up growth are unclear.A f.nctional treatment concept,used in our centre f.r 25 years,includes an individualized palatal plate with a velo-pharyngeal extension and intensive f.eding *** We perf.rmed a prospective study to objectively describe f.cial prof.les in inf.nts with RS treated with the above *** with isolated RS were admitted to our tertiary perinatal and national ref.rral centre f.r craniof.cial malf.rmations between May 2018 and Nov *** with RS received 3D-photographs during clinically indicated *** controls were recruited f.om Dec 2018 to Sep 2019 and received 3D-photographs every 3 *** digitally measured jaw index(JI),def.ned as alveolar overjet(O)x maxillary arch(U)/mandibular arch(L),and the sof. tissue ref.rence points A’-point,Nasion’,B’-point angle(ANB’),describing the relative position of.maxilla to mandible,were *** mixed models were used to examine time trajectories in JI and ANB’.Results A total of.2073D images,obtained in 19 inf.nts with RS and 32 controls,were *** and ANB’decreased over time in both groups[f.r JI−0.18(95%CI−0.25 to−0.10);f.r ANB’:−0.40°per month[(95%CI−0.48 to−0.32)]]but remained lower in controls[f.r JI−2.5(95%CI−3.2 to−1.8);f.r ANB’-1.7°(95%CI−2.4 to−1.0)].Also,the ANB’model showed a signif.cant ef.ect of.the interaction term diagnosis x *** Based on longitudinal 3D images,we describe changes in objective parameters of.f.cial prof.le in inf.nts with and without RS during the f.rst year of.*** f.ndings indicate catch-up growth in inf.nts treated f.r RS.

关键词： Inf.nt Mandibular catch-up growth Pre-epiglottic Baton Plate Robin sequence Three-dimensional photography

Design of.a Novel Exoskeleton with Passive Magnetic Spring Self.locking and Spine Lateral Balancing

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Journal of.Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon f.Rodríguez-León Betsy D.M.Chaparro-Rico Daniele Caf.lla f.ancesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico Department of.Mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly f.culty of.Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive Degrees of.f.eedom(Dof..Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomf.rt and spinal torsional ef.ects also helping in limb weight *** paper reports specif.c models and simulations to demonstrate the f.asibility and ef.ectiveness of.the proposed *** experimental characterization is perf.rmed to validate the perf.rmance of.the mechanism in terms of.f.rces and physical strain during a specif.c application consisting of.ceiling-surf.ce drilling *** obtained results preliminarily validate the engineering f.asibility and ef.ectiveness of.the proposed exoskeleton in the intended operation task thereby requiring the user to exert signif.cantly less f.rce than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Bulking Up the Bay-Position Substituents Enables Enhanced Selectivity of.C_(s)‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina f.f.rac Alan J.Lough Timothy P.Bender Department of.Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of.Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of.Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of.Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of.subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of.f.nctional ***,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Nc_(p))s,are desirable f.r this purpose yet synthetically challenging due to random mixtures of.C_(s-),C_(3v-),and,in some cases,C_(1)-symmetric compounds that f.rm during traditional statistical mixed ***,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity f.r the targeted C_(s)-symmetric hybrid and complete suppression of.sterically crowded macrocyclic *** process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of.bay-position phenylated Ph_(2)-(R_(p))_(8)Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or f.in their peripheral isoindole *** selectivity ranged between 59 and 72%with remarkable yields,signif.cantly higher than that of.conventional mixed *** f.ndings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle ***,the incorporation of.unf.sed phenyl groups and halogen atoms into the hybrid f.amework resulted in f.ne-tuned optical,structural,electronic,and electrochemical *** straightf.rward approach achieved improved selectivity and controlled narrowing of.the product distribution,af.ording the ef.icient synthesis of.structurally sophisticated Bsub(Pc_(2)-Nc_(1))*** then expands the library of.3-dimensionalπ-extended macrocycles f.r use in a range of.applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

The ef.ects of.local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第06期 22-36页

作者： Stephen f.f.ley Chunf.i Chen Dorrit E.Jacob School of.Natural Sciences Macquarie University Research School of.Earth Sciences Australian National University State Key Laboratory of.Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of.carbon released by gradual degassing f.om the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong inf.uences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen f.gacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of.rock types coexist. Carbonate-rich melts f.om either subduction or melting of.the uppermost asthenosphere trap carbon by redox f.eezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may f.rm f.rther diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of.the TBL and lower lithosphere down so that they melt by a mixture of.heating and oxidation, or by lateral advection of.solids beneath rif.s. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of.craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are f.ne-tuning our understanding of.processes and turning up unexpected results that are not seen in studies of.single rocks. f.ture research should concentrate on elucidating local variations and integrating these with the interpretation of.geophysical signals. Global concepts such as average sediment compositions and a unif.rm mantle oxidation state are not appropriate f.r small-scale processes; an increa

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