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

National Science Review 2024年第6期11卷 22-36页

作者： Stephen f.foley Chunfei Chen Dorrit e.Jacob School of Natural Sciences Macquarie University Research School of.e.rth 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 from 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 influences 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 fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox f.e.zing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further 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 rifts. 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 fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. future 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 uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

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All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes f.e.Jorge A.Canal Neto Departamento de fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational f.e.uencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

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ef.e.ts of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： f.Animah C.Keles W.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the ef.e.tiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the ef.e.t of two dif.e.ent scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably af.e.ted by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an ef.e.t of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber Canopy air curtain Silica

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Modelling the brittle rock failure by the quaternion-based bonded-particle model in DeM

Rock Mechanics Bulletin

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Rock Mechanics Bulletin 2024年第2期3卷 87-95页

作者： Tao Zhao Philip e.f.Collins Department of Civil and environmental engineering Brunel University LondonLondonUB83PHUnited Kingdom

This paper presents an investigation of brittle rock failure by the quaternion-based bonded-particle model in discrete element method(DeM).Unlike traditional approaches that utilize euler angles or rotation matrices,this model employs unit quaternions to represent the spatial rotations of *** method simplif.e. the rep-resentation of 3D rotations,providing a more intuitive framework for modelling complex interactions in granular *** numerical model was validated by the uniaxial compression tests on rock,with good agreement with well-documented experimental data in terms of the rock uniaxial compression strength(UCS)and failure *** loading,the rock sample demonstrated a linear-elastic response at an axial strain of smaller than 0.45%.However,as internal bond breakage accumulated,this linear relationship weakened,and the stress-strain curve began to deviate from its initial linear *** bond breakage and the overall deformation of the rock were primarily controlled by the shear bonding *** UCS was achieved at an axial strain of 0.625%,at which point the internal shear bonding force chains were predominantly aligned *** brittle failure occurred when the internal damage of solids nucleated to form an interconnected failure plane,accompanied by a sharp rise in the internal damage *** area of failure plane increased with the loading strain rate,gradually transforming the failure pattern from the local damage to a complete fragmentation.

关键词： Brittle failure Quaternion DeM bonded model Uniaxial compression test Rate dependent Internal damage

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Transient elastography and diffusion-weighted magnetic resonance imaging for assessment of liver fibrosis in children with chronic hepatitis C

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World Journal of Virology 2024年第3期13卷 89-97页

作者： Mohamed A el-Guindi Alif A Allam Ahmed A abdel-Razek Gihan A Sobhy Menan e Salem Mohamed A abd-Allah Mostafa M Sira Pediatric Hepatology Gastroenterology and NutritionNational Liver InstituteMenoufia UniversityShebin El-Koom 32511MenoufiaEgypt Department of Diagnostic Radiology Mansoura Faculty MedicineMansoura 13551Egypt

BACKGROUND Chronic hepatitis C(CHC)is a health burden with consequent morbidity and *** biopsy is the gold standard for evaluating fibrosis and assessing disease severity and prognostic purposes *** altern-atives for liver biopsy such as transient elastography(Te)and diffusion-weighted magnetic resonance imaging(DW-MRI)are critical *** To evaluate Te and DW-MRI as noninvasive tools for predicting liver fibrosis in children with *** This prospective cross-sectional study initially recruited 100 children with CHC virus ***-four children completed the full set of investigations including liver stiff.e.s measurement(LSM)using Te and measurement of apparent diffusion coefficient(ADC)of the liver and spleen using *** biopsies were evaluated for fibrosis using Ishak scoring *** and liver and spleen ADC were compared in dif.e.ent fibrosis stages and correlation analysis was performed with histopathological findings and other laboratory *** Most patients had moderate fibrosis(73.5%)while 26.5%had mild *** had severe fibrosis or *** majority(68.8%)had mild activity,while only 7.8%had moderate *** scores had a significant direct correlation with LSM(P=0.008)and were negatively correlated with both liver and spleen ADC but with no statistical significance(P=0.086 and P=0.145,respectively).Similarly,histopatho-logical activity correlated significantly with LSM(P=0.002)but not with liver or spleen ADC(P=0.84 and 0.98 respectively).LSM and liver ADC were able to significantly discriminate f3 from lower fibrosis stages(area under the curve=0.700 and 0.747,respectively)with a better performance of liver *** Te and liver ADC were helpful in predicting significant fibrosis in children with chronic hepatitis C virus infection with a better performance of liver ADC.

关键词： Apparent diffusion coefficient Chronic hepatitis C Diffusion-weighted magnetic resonance imaging Liver fibrosis Liver stiff.e.s Transient elastography

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Comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.eggleton Cody J.Salzmann Joseph e.Kaiser Shannon C.f.Smith Department of Aquaculture and fisheries University of Arkansas at Pine Bluff Arkansas Game and fish Commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were of.e. greater(P e post-carp period as ref.e.ted by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages dif.e.ed structurally between pre-carp and post-carp periods. Assemblage dif.e.ences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. Conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species fish assemblage Oxbow lake Large river

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Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： J.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the f.e.d should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

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evaluation of the nutritional value of Artemia nauplii for european seabass(Dicentrarchus labrax L.)larvae

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Aquaculture and fisheries 2024年第1期9卷 78-84页

作者： Alaa A.el-Dahhar Rashwan S.Rashwan samy Y.el-Zaeem Shaimaa A.Shahin Mona M.Mourad Mohammed f.e. Basuini Animal and fish Production Department Faculty of Agriculture-Saba BashaAlexandria UniversityAlexandria21526Egypt National Institute of Oceanography and fisheries(NIOf) Cairo11562Egypt Department of Animal Production Faculty of AgricultureTanta UniversityTanta31527Egypt faculty of Desert Agriculture King Salman International UniversitySouth Sinai46618Egypt

Adapted european seabass(Dicentrarchus labrax L.)larvae at 25 days post-hatching(dph)with a primary weight and length of 23 mg and 9.92 mm,start the weaning up to 46 dph using the weaning micro-diet(54%crude protein from fish meal,powder milk,and poultry egg)concurrently with Artemia enriched with fortification emulsions(0.6 g/L)of DHA selco®as a control group(DHAS)or fish oil+20%Vitamin C(fOVC),or fish oil+20%Vitamin e(fOVe),or fish oil+10%Vit.C+10%Vit.e(fOCe),or fish oil only(fO).At 46 dph,groups of larvae fed enriched Artemia with DHAS and fOVe exhibited the highest final body weight,weight gain,average daily gain,specific growth rate,f.e. intake,protein efficiency ratio,and survival%as well as the lowest f.e. conversion ***,larvae in fOVC displayed the lowest final body weight,total length,weight gain,average daily gain,specific growth rate,f.e. intake,protein efficiency ratio,and survival%as well as the highest f.e. conversion *** histological assessment exhibited no pathological alteration as well as an improvement in the structure with DHAS,fOVe,fOVC,and fOCe co-additives compared to *** peroxidase enzyme(GPx)recorded the highest rates(Pfed Artemia supplemented with DHAS and fOVe followed by fOCe and *** the lowest record for GPx activity was noted in the fO *** conclusion,Using augmented Artemia nauplii with fish oil+vitamin e in single or in companion with vitamin C as cheap antioxidants support *** larval growth,survival,and antioxidant efficacy during the critical weaning period.

关键词： european seabass Gastrointestinal histology Antioxidants Vitamin C Vitamin e DHA

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Prospective cohort study on facial profile changes in infants 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 for Cleft Lip Palate and Craniofacial MalformationsTuebingen University HospitalTuebingenGermany Department of Orthodontics Tuebingen University HospitalTuebingenGermany Department of Oral and Maxillofacial Surgery Tuebingen University HospitalTuebingenGermany

Background Various conservative and surgical approaches exist to treat Robin sequence(RS),but their ef.e.ts on facial profile and mandibular catch-up growth are unclear.A functional treatment concept,used in our centre for 25 years,includes an individualized palatal plate with a velo-pharyngeal extension and intensive f.e.ing *** We performed a prospective study to objectively describe facial profiles in infants with RS treated with the above *** with isolated RS were admitted to our tertiary perinatal and national referral centre for craniofacial malformations between May 2018 and Nov *** with RS received 3D-photographs during clinically indicated *** controls were recruited from Dec 2018 to Sep 2019 and received 3D-photographs every 3 *** digitally measured jaw index(JI),defined as alveolar overjet(O)x maxillary arch(U)/mandibular arch(L),and the soft tissue reference 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 infants with RS and 32 controls,were *** and ANB’decreased over time in both groups[for JI−0.18(95%CI−0.25 to−0.10);for ANB’:−0.40°per month[(95%CI−0.48 to−0.32)]]but remained lower in controls[for JI−2.5(95%CI−3.2 to−1.8);for ANB’-1.7°(95%CI−2.4 to−1.0)].Also,the ANB’model showed a significant ef.e.t of the interaction term diagnosis x *** Based on longitudinal 3D images,we describe changes in objective parameters of facial profile in infants with and without RS during the first year of *** findings indicate catch-up growth in infants treated for RS.

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

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enhancing high-temperature oxidation resistance(at 1000 °C) of nickel superalloy obtained by laser powder bed fusion via reactive electric spark treatment

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Transactions of Nonferrous Metals Society of China 2024年

作者： S.K.MUKANOV M.I.PeTRZHIK A.e.KUDRYASHOV e.A.NAUMOVA f.A.BASKOV P.A.LOGINOV e.A.LeVASHOV National University of Science and Technology MISIS

The high-temperature oxidation resistance of the nickel superalloy grown by the Laser Powder Bed fusion (LPBf) has been significantly increased as a result of in-situ formation of a thermal barrier layer (α-Al2O3+ CaMoO4) during oxidative annealing of surface layers modif.e. by electric spark treatment (eST). The reactive eST of the LPBf-built items based on nickel eP741NP alloy was carried out with low-melting Al-12%Si， Al-6%Ca-0.6%Si and Al-7%Ca-1%Mn electrodes. It was found that at eST done by Al-7%Ca-1%Mn electrode an intermetallic (β-NiAl + γ’-Ni3Al) 15 microns thick layer reinforced by spherical oxide (CaMe)O nanoparticles was formed. formation of that structure increases the wear resistance of LPBf nickel superalloy by 4.5 times. further oxidative annealing at 1000 °C lead to a formation of continuous two-layered coating with an inner layer of α-Al2O3and an outer layer of CaMoO4， which together act as an ef.e.tive barrier preventing the diffusion of oxygen into the volume of the superalloy.

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