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Rumen microbial degradation of bromoform from red seaweed(Asparagopsis taxiformis)and the impact on rumen fermentation and methanogenic archaea

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Journal of Animal Science and Biotechnology 2024年第1期15卷 412-426页

作者： Pedro Romero Alejandro Belanche Elisabeth Jiménez Rafael Hueso Eva Ramos-Morales Joan King Salwen Ermias Kebreab David R.y.ñez-Ruiz Estacion Experimental del Zaidin Consejo Superior de Investigaciones Cientificas(CSIC)Profesor Albareda 1Granada 18008Spain Department of Animal Production and Food Sciences University of ZaragozaMiguel Servet 177Saragossa 50013Spain Blue Ocean Barns Inc. Redwood CityCAUSA Department of Animal Science University of CaliforniaDavisCA 95618USA

Background The red macroalgae Asparagopsis is an effective methanogenesis inhibitor due to the presence of halogenated methane(CH_(4))analogues,primarily.bromoform(CHBr_(3)).This study.aimed to investigate the degradation process of CHBr3 from A taxiformis in the rumen and whether this process is *** in vitro batch culture sy.tem was used according to a 2×2 factorial design,assessing two A taxiformis inclusion rates[0(CTL)and 2%DM diet(AT)]and two diets[high-concentrate(HC)and high-forage diet(HF)].Incubations lasted for 72 h and samples of headspace and fermentation liquid were taken at 0,0.5,1,3,6,8,12,16,24,48 and 72 h to assess the pattern of degradation of CHBr_(3) into dibromomethane(CH_(2)Br_(2))and fermentation ***,an in vitro experiment with pure cultures of seven methanogens strains(Methanobrevibacter smithii,Methanobrevibacter ruminantium,Methanosphaera stadtmanae,Methanosarcina barkeri,Methanobrevibacter millerae,Methanorhermobacter wolfei and Methanobacterium mobile)was conducted to test the effects of increasing concentrations of CHBr3(0.4,2,10and 50μmol/L).Results The addition of AT significantly.decreased CH_(4) production(P=0.002)and the acetate:propionate ratio(P=0.003)during a 72-h *** concentrations of CHBr_(3) showed a rapid decrease with nearly.90%degraded within the first 3 h of *** the contrary.CH_(2)Br_(2) concentration quickly.increased during the first 6 h and then gradually.decreased towards the end of the *** CHBr_(3) degradation nor CH_(2)Br_(2) sy.thesis were affected by.the ty.e of diet used as substrate,suggesting that the fermentation rate is not a driving factor involved in CHBr_(3)*** in vitro culture of methanogens showed a dose-response effect of CHBr3 by.inhibiting the growth of ***,***,***,***,***,***,and *** The present work demonstrated that CHBr_(3) from *** is quickly.degrad

关键词： Bromoform metabolism Dibromomethane metabolism Methane mitigation Methanogens Rumen microbiota Seaweed

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Seismic attribute and well-log analy.is for channel characterization in the upper San Andres and Gray.urg formations of the Midland Basin,Texas

Energy Geoscience

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Energy.Geoscience 2024年第2期5卷 263-278页

作者： Sumit Verma Esra y.lçın y.lmaz Laura Ortiz Sanguino Justin y.ndell Miles A.Henderson Robert C.Trentham Department of Geosciences The University of Texas Permian BasinOdessaTXUSA School of Geosciences The University of OklahomaNormanOKUSA

The Permian Basin is one of the most prolific,and currently.one of the most active,oil and gas basins in the *** Lower Permian strata in the Permian Basin have produced more than 14 billion barrels of oil(BBO),making it the largest volume of hy.rocarbon in the *** in the Midland Basin during late Leonardian through early.Guadalupian(ca.272e269 Ma)resulted in progradation of shelf edge and ultimately.closure of the basin by.Middle Permian *** analy.ed a merged seismic survey.covering parts of the Permian Basin(i.e.,Central Basin Platform and Midland Basin)in Andrews,Ector,and Midland Counties,*** seismic survey.and well logs show the presence of gently.dipping(ca.1°)clinoforms in the Upper San Andres and Gray.urg Formations on the eastern edge of the Central Basin Platform and western Midland *** seismic attributes,curvature,and spectral decomposition identify.low sinuosity.slope channels oriented north-south,but such channels do not appear bey.nd the *** shelf edge shifts from north to south during deposition of the Upper San Andres and Gray.urg *** identify.five basinward shifts noted by.the migration of the shelf edge toward the basin center and the presence of channel features along the depositional *** petrophy.ical analy.is indicates that channels cut into carbonate rocks and are filled by.siliciclastic sediments;this interpretation is supported by.the most negative curvature anomalies along the channel axes caused by.the differential compaction between the carbonate and siliciclastic *** are a few channels with a northwest-southeast strike,which matches the direction of the Concho Lineament observed by.satellite *** observations are consistent with previous interpretations of the northern Midland Basin closure during Middle-Late Permian time.

关键词： Permian shelf carbonate

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Effect of terrain and building structures on the airflow in an airport

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Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2012年第6期13卷 461-468页

作者： Dennis y. C. LEUNG W. y. LO W. y. CHOW P. W. CHAN Department of Mechanical Engineering The University of Hong Kong Hong Kong China Hong Kong Observatory Hong Kong China

The aim of this study.was to perform computational fluid dy.amics (CFD) simulations on the airflows at the Hong Kong International Airport (HKIA). In particular, the effects of hangar buildings and terrain were studied to explore the effects of turbulence on fly.ng aircraft, especially.during landing. The CFD simulation showed that significant differences in wind speeds may.occur between the north and the south runway. on the western part of the HKIA under ty.hoon conditions with a strong north to northwesterly.wind. Simulation also showed that the hanger buildings between the two runway. on the western side and the nearby.terrain could be causing the observed difference in the wind speeds. The results also indicated that these obstacles could cause significant wind speed variations at the western end of the south runway. This may.affect the operation of landing aircraft. The CFD results for a ty.ical ty.hoon case were analy.ed and found to match the wind data recorded by.an aircraft landing that day.

关键词： Computational fluid dy.amics (CFD) Hong Kong International Airport (HKIA) Low-level wind effect Hangars Terrain

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A GLOBAL ALGORITHM IN THE NUMERICAL RESOLUTION OF THE VISCOUS/INVISCID COUPLED PROBLEM

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Chinese Annals of Mathematics,Series B 1997年第2期18卷 191-200页

作者： XUCHUANJU MADAy.y. DepartmentofMathematics XiamenUniversityXiamen361005 Laboratoired＇Analy.eNumerique UniversitePierreetMarieCurieParisFrance.

This paper deals with the spectral approximation of an incompressible viscous/inviscid coupled model. An efficient Uzawa algorithm based on a new variational formulation is proposed. The generalization to the coupl... 详细信息

关键词： Coupled equations Navier-Stokes equations Euler equations Spectral discretization Global Uzawa algorithm

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Two sides of the heliopause

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Science China Earth Sciences 2011年第12期54卷 1830-1844页

作者： WHANG y. C Catholic University.of America

Interaction of the solar wind with the interstellar medium leads to the formation of the heliosphere and termination shock. This article addresses three aspects of the plasma and magnetic field on two sides of the heliopause：（1） The interstellar magnetic field surrounding the heliopause. In the limit of very.low plasma β-ratio an analy.ical solution is obtained for the 3D interstellar magnetic field by.means of a line dipole method. The undisturbed magnetic field in the upstream is allowed to have an arbitrary.inclination angle. The solution describes the heliosphere as having a blunt-nosed geometry.on the upwind side and approaching a cy.indrical geometry.on the downwind side. The distortion of the magnetic field can penetrate very.deep into the interstellar space. （2） Interaction of the interstellar neutral hy.rogen with the global solar wind. The ionization process leads to removal of interstellar neutral hy.rogen in the heliosphere： on the upwind side, 90% of hy.rogen depletion occurs inside 60 AU, the hy.rogen density.changes rapidly.inside 10 AU. A hy.rogen cavity.forms inside -4 AU; the cavity.extends on the downwind side to form a long cavity.wake. Outside the cavity.and cavity.wake, pickup protons are produced, they.cause deceleration and heating of the solar wind. The wind speed and temperature also increase steadily.with heliolatitude caused by.the latitudinal increase in wind speed at the inner boundary. （3） The global geometry.of the termination shock. The termination shock has been treated as having a closed geometry.in previous heliosphere models. This study.presents a new perspective that the global termination shock may.have a bow-shaped open geometry. The termination shock forms on the upwind side because the forward motion of the supersonic solar wind is blocked at the blunt-nosed heliopause. However, the heliopause likely.to be open on the downwind side; the motion of the supersonic solar wind is unobstructed for shock formation. Thus, the globa

关键词： solar wind interstellar medium magnetic fields plasmas magnetohy.rody.amics (MHD)

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Mechanosy.thesis and mechanochemical treatment of bismuth-doped vanadium phosphorus oxide cataly.ts for the partial oxidation of n-butane to maleic anhy.ride

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Journal of Natural Gas Chemistry 2008年第3期17卷 232-237页

作者： y. H. Taufiq-y.p y.C. Wong y. Kamiy. W.J. Tang Putra Center for Cataly.is Science and Technology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate School of Environmental Science Hokkaido Universit3 Sapporo 060-0810 Japan

Three Bi-doped vanady. py.ophosphate cataly.ts were prepared via dihy.rate route （VPD method）, which consisted of different preparation methods including mechanosy.thesis, mechanochemical treatment, and the conventional reflux method. The cataly.ts produced by.the above three methods were characterized by.x-ray.diffraction （XRD）, scanning electron microscopy.（SEM）, and temperature programmed reduction （TPR）. Cataly.ic evaluation for the partial oxidation of n-butane to maleic anhy.ride （MA） was also carried out. The XRD patterns of all the Bi-doped cataly.ts showed the main peaks of py.ophosphate phase. Lower intensity.peaks were observed for the mechanochemically.treated Bi-doped cataly.t （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxy.en species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the cataly.ic test results, the graph of selectivity.to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective cataly.t. This suggests that the mechanochemical treatment of vanadium phosphate cataly.t （VPDBiMill） is a potential method to improve the cataly.ic properties for the partial oxidation of n-butane to maleic anhy.ride.

关键词： mechanosy.thesis mechanochemical treatment bismuth vanady. py.ophosphate

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ARTIFICIAL NEURAL NETWORK MODEL OF CONSTITUTIVE RELATIONSHIP FOR 2A70 ALUMINUM ALLOy

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 719-723页

作者： F. Liu D.B. Shan y. Lu y. y. y.ng School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The hat deformation behavior of 2A70 aluminum alloy.was investigated by.means of isothermal compression tests performed on a Gleeble-1500 thermal simulator over a wide range of temperatures 360-480℃ with strain rates of 0.01-1s^-1 and the largest deformation of 60%, and the true stress of the material was obtained under the above-mentioned conditions. The experimental results shows that 2A70 aluminum alloy.is a kind of aluminum alloy.with the property.of dy.amic recovery. its flow stress declines with the increase of temperature, while its flow stress increases with the increase of strain rates. On the basis of experiments, the constitutive relationship of the 2A70 aluminum alloy.was constructed using a BP artificial neural network. Comparison of the predicted values with the experimental data shows that the relative error of the trained model is less than ±3% for the sampled data while it is less than ±6% for the nonsampled data. It is evident that the model constructed by.BP ANN can accurately.predict the flow stress of the 2A70 alloy.

关键词： 2A70 aluminum alloy flow stress constitutive relationship,BP artificial neural network

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Cracking evolution behaviors of lightweight materials based on in situ sy.chrotron X-ray.tomography. A review

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Frontiers of Mechanical Engineering 2018年第4期13卷 461-481页

作者： y. Luo S. C. Wu y. N. Hu y. N. Fu State Key.Laboratory.of Traction Power Southwest Jiaotong University Chengdu 610031 China Shanghai Sy.chrotron Radiation Facility Shanghai 201204 China

Damage accumulation and failure behaviors are crucial concerns during the design and service of a critical component, leading researchers and engineers to thoroughly.identify.ng the crack evolution. Third-generation sy.chrotron radiation X-ray.computed microtomo- graphy.can be used to detect the inner damage evolution of a large-density.material or component. This paper provides a brief review of study.ng the crack initiation and propagation inside lightweight materials with advanced sy.chrotron three-dimensional （3D） X-ray.imaging, such as aluminum materials. Various damage modes under both static and dy.amic loading are elucidated for pure aluminum, aluminum alloy.matrix, aluminum alloy.metal matrix composite, and aluminum alloy.welded joint. For aluminum alloy.matrix, metallurgical defects （porosity. void, inclusion, precipitate, etc.） or artificial defects （notch, scratch, pit, etc.） strongly.affect the crack initiation and propagation. For aluminum alloy.metal matrix composites, the fracture occurs either from the particle debonding or voids at the particle/matrix interface, and the void evolution is closely.related with fatigued cy.les. For the hy.rid laser welded aluminum alloy. fatigue cracks usually.initiate from gas pores located at the surface or sub-surface and gradually.propagate to a quarter ellipse or a ty.ical semi-ellipse profile.

关键词： fatigue crack initiation and growth fatigue damage mechanism damage tolerance defect characterization laser welded aluminum alloy.

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In situ TEM investigation of electron irradiation and aging-induced high-density.nanoprecipitates in an Mg-10Gd-3y.1Zn-0.5Zr alloy

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Journal of Magnesium and Alloy. 2024年第5期12卷 1841-1853页

作者： M.Lv H.L.Ge Q.Q.Jin X.H.Shao y.T.Zhou B.Zhang X.L.Ma Sheny.ng National Laboratory.for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density.precipitates in an Mg-10Gd-3y.1Zn-0.5Zr(GWZ1031K,wt.%)alloy.to improve the *** results show that the hardness of the Mg alloy.after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately.64% higher than that of the samples before being *** is mainly.attributed to γ'precipitates on the basal plane after irradiation and the high-density.nanoscale β'precipitates on the prismatic plane after aging,which should be closely.related to the irradiation-induced homogenous *** latter play. a key.role in precipitation *** result paves a way.to improve the mechanical properties of metallic materials by.tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ TEM

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Analy.is of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity.Amplitude in the Star RR Ly.

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Research in Astronomy.and Astrophy.ics 2024年第6期24卷 253-272页

作者： y.El jariri F.L.Sefy.ni A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de phy.ique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity.curves of hy.rogen and metallic lines within the atmosphere of pulsating *** this article,we present a study.of this phenomenon through the spectra of the brightest pulsating star RR Ly. of RR Ly.ae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the y.ars 1994 and 1997 at the Observatory.of Haute Provence(OHP,France)previously.observed by.Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory.Morocco)between 2015 and *** this study.we have detected information on atmospheric dy.amics that had not previously.been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hy.rogen and those of the metallic lines has been observed and analy.ed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity.curves deduced from the lines of hy.rogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cy.le and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by.the Blazhko ***,toward the minimum of the Blazhko cy.le the Van Hoof effect is more visible and at the maximum of the Blazhko cy.le,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Ly.ae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Ly.)

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