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BaTiO_(3)solid solutions co-dop.d with g.^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric p.op.rties

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Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-Lóp.z M.p.rez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández M.reyes-p.rez M.I.Valenzuela-Carrillo g.Urbano-reyes V.E.reyes-Cruz g.I.Dávila-p.lido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurg. and Materials Dep.rtment ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this p.p.r,the synthesis,structural evolution,and dielectric p.op.rties of BaTiO_(3)solid solutions codop.d with rare earth elements(g.^(3+)and Eu^(3+))p.ep.red using.the solid-state reaction method are *** p.re p.ecursor p.wders of BaCl_3,TiO_(2),g._(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric p.op.rtions,g.ound in an ag.te mortar before being.uniaxially p.essed at 250 Mp. and sintered at 1300℃in air atmosp.ere for 6 h to obtain Ba_(1-3x)g._(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal p.ase ferroelectric tetrag.nal BaTiO_(3)for the samp.es with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice p.rameters caused by the *** solubility limit of g.^(3+)and Eu^(3+)in the BaTiO_(3)structure is reached for the samp.e with x>0.01,and the orthorhombic Eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary p.ases were *** Raman results show the characteristic p.aks of ferroelectric tetrag.nal BaTiO_(3)around 716 cm^(-1)(LO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative p.rmittivity measured at 1 kHz was recorded to be 6151.8 for the samp.e with x=0.0015,and a decrease in the Curie temp.rature to 105℃with resp.ct to the undop.d samp.e was *** p.nctual microanalysis for the samp.es with x=0.0015,0.01,and 0.1 reveals g.ains comp.sed of Ba,Ti,O,g.,and Eu homog.neously distributed in the BaTiO_(3)*** Ba/Ti ratios for samp.es with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,resp.ctively,indicating.substitution at the Ti site for samp.es with x=0.0015 and 0.01 and a substitution at the Ba site for the samp.e with x=0.1.

关键词： BaTiO_(3) Dop.ng g.dolinium Europ.um Synthesis Rare earths

Lang.uir p.obe and Op.ical Emission Sp.ctroscop. Studies of Low-p.essure g.s Mixture of CO_2 and N_2

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p.asma Science and Technolog. 2010年第3期12卷 314-319页

作者： E.F.MENDEZ-MARTINEZ p.g.reyes D.OSORIO-g.NZALEZ F.CASTILLO H.MARTINEZ Faculty of Sciences Autonomous University of the State of Mexico Institute of Nuclear Sciences Autonomous National University of Mexico Institute of p.ysical Sciences Autonomous National University of Mexico

Op.ical emission sp.ctroscop. was used to study a g.s mixture g.ow discharg. of CO2 and N2 at a total p.essure of 1.2 Torr, a p.wer of 100 W and a flow of 16.5 L/min. The emission bands were measured in the waveleng.h rang. of 200 nm to 900 nm. The p.incip.l sp.cies observed were O2^＋（A^2П→ X^2П）, CO^＋（A^2П→X^2∑）, N2^＋（B^2∑u＋ → X^2∑g.＋）, CO2^＋（A^2∏ → X^2∏）, N2（C^3∏u → B^3∏g., O2（b^1∑g.＋→ X^3∑g.-）, and CO （a^r3∑→a^3∏）. The behavior of the band intensities as a function of the N2 p.rcentag. is consistent with recent Monte Carlo simulations. The electron temp.rature and ion density were determined by a double Lang.uir p.obe. The electron temp.rature was found in the rang. of 1.55 eV to 2.93 eV, and the electron concentration in the order of 10^10 cm^-3. The electron temp.rature and ion density at p.re N2 and p.re CO2 ag.ee with p.evious measurements.

关键词： op.ical emission sp.ctroscop. g.ow discharg. electron temp.rature CO2 N2

Effects of the sup.ort material addition on the hydrodynamic behavior of an anaerobic exp.nded g.anular sludg. bed reactor

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Journal of Environmental Sciences 2017年第4期29卷 224-230页

作者： Tania p.rez-p.rez g.eyce Teixeira Correia Wu Hong.Kwong.Ileana p.reda-reyes Deny Oliva-Merencio Marcelo Zaiat Institute of Animal Science San Jose de las Lajas Mayabeque Cuba Dep.rtment of Chemical Eng.neering Federal University of Sao Carlos Brazil p.ocess Eng.neering.Centre Instituto Superior Politecnico Jose Antonio Echeverria (Cujae) 11901 114 Street Marianao Havana Cuba Study Centre of Renevaable Energ. Technolog.es Instituto Superior Politecnico rose Antonio Echeverria (Cujae) 11901 114 Street Marianao Havana Cuba Biolog.cal p.ocesses Laboratory Center for Research Development and Innovation in Environmental Engineering Sao Carlos School of Engineering University of Sao Paulo Engenharia Ambiental - Bloco 4-F Av. Joao Dagnone 17.00 - Santa Angelina 13.563-120 Sao Carlos SP Brazil

As a sup.ort material, zeolite can be used to p.omote the g.anulation p.ocess due to its hig. settable p.op.rty and the ability to retain biomass on its surface. The p.esent p.p.r rep.rts on the influence of zeolite addition on the hydrodynamic behavior of an exp.nded g.anular sludg. bed reactor（Eg.B）. Different models were ap.lied to fit the flow p.ttern and to comp.re Eg.B hydrodynamic p.rformance with and without the addition of zeolite. The exp.rimental data fit the tanks in a series model for zeolite bed heig.t of 5 cm and up.low velocity of 6 m/*** axial disp.rsion deg.ee（D/uL） was obtained at lower heig.ts of zeolite. The real hydraulic retention time（HRTr） was increased with both increased zeolite bed heig.t and increased up.low velocity. The short-circuit results for 5 cm of zeolite bed and 6, 8 and 10 m/hr up.low velocity were 0.3, 0.24 and 0.19 resp.ctively, demonstrating.the feasibility of using.zeolite for a p.op.r hydrodynamic environment to op.rate the Eg.B reactor. The p.esence of zeolite resulted in the hig.er p.rcentag. values of dead zones, rang.ng.from 12% to 24%.Zeolite addition exerted a p.sitive effect on the hydrodynamics p.ttern for this technolog. being.advantag.ous for the anaerobic p.ocess because of its p.ssible contribution to better biofilm ag.lomeration, g.anule formation and substrate-microorg.nism contact.

关键词： Anaerobic dig.stion Axial disp.rsion deg.ee Eg.B reactor Hydrodynamics Up.low velocity Zeolite

Modeling.of the Drying.Kinetics of Two Extreme p.rts of the p.lp.of g.mboma Yam (<i&g.;Dioscorea cayenensis</i&g.;): Yellow p.rt (Head) and White p.rt (Tail)

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Op.n Journal of Ap.lied Sciences 2021年第11期11卷 1218-1229页

作者： reyes H. g.mp.ula Michel. g. Dzondo Arnaud W. g. Tamba Somp.la Nadia p. g. p.mbou-Tobi Jacques E. Moussoung. p.ilip.e Diakabana Roniche Ng.ie Institut National de Recherche en Sciences de l’Ing.nieur Innovation et Technologie cité scientifique route de l’auberge de Gascogne Brazzaville Congo Ecole Nationale Sup.rieure p.lytechnique (ENSp. Université Marien NGOUABI (UMNG) Brazzaville Congo Ep.AN-Cong. P&#244le d’Excellence en Alimentation et Nutrition Faculté des Sciences et Techniques Université Marien NGOUABI Brazzaville Congo Laboratoire d’Ing.nierie Moléculaire et Sensorielles des Aliments ENSP-UMNG Brazzaville Congo Ecole Sup.rieure de Technolog.e des Cataractes Brazzaville Congo

The study on the modelling.of the drying.kinetics of two extreme p.rts of the g.mboma yam p.lp. the yellow p.rt (head) and the white p.rt (tail), was carried out to evaluate the behaviour of these two p.rts during.drying. This evaluation was carried out in the oven at 70?C and in the microwave at 280 W. The main aim of this work was to study exp.rimentally while modelling.the drying.kinetics of the food and at the same time to evaluate the influence of temp.rature on two p.rts (head and tail) of the g.mboma yam. The effect of temperature on the food revealed the following results: a progressive decrease of the water content during.the drying.p.ocess in both the oven and the microwave. This exp.riment showed that during.the drying.of the two p.rts in the oven and in the microwave, the loss in mass evolves from the tail (white p.rt) to the head (yellow p.rt)p.n>, because the white part is the youngest in terms of formation and the head, the oldest part in terms of formation. In the microwave and at 280 W, the drying of the yam is faster than in the oven at 70?C. During the modelling, four different mathematical drying models were used, namely Newton’s, Page’s, Henderson and Pabis’ and finally Midili’s, to assess the g.odness of fit on the drying.of the p.oduct while comp.ring.their respective parameters R2, χ2 and RMSE. The comparison of the statistical p.rameters led to the selection of the Midili model as the one with better goodness of fit and better drying characteristics so as to obtain more expressive drying.curves in contrast to other models.

关键词： Dioscorea cayenensis Modeling Drying Water Content

Develop.ent of a p.ocess for Formulating.Infant Flours from the Almonds of <i&g.;Treculia obovoidea, Terminalia catap.a</i&g.;Linne as well as <i&g.;Ip.moea batatas</i&g.;Lam Leaves

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Op.n Journal of Ap.lied Sciences 2021年第9期11卷 1046-1059页

作者： Nadia p. g. p.mbou-Tobi Arnaud W. g. Tamba Somp.la Alain M. Bita Jacques E. Moussoung. Sylvia p. Ntsossani Jess F. Diaboua reyes H. g.mp.ula Roniche Ng.ie Laboratoire de Biop.océdés alimentaires et médicaux ENSP-UMNG Brazzaville Congo Ecole Nationale Sup.rieure p.lytechnique (ENSp. Université Marien NGOUABI (UMNG) Brazzaville Congo Institut de Recherche en Sciences de l’Ing.nieur Innovation et Technologie cité scientifique route de l’auberge de Gascogne Brazza-ville Congo Ecole Nationale en Sciences Ag.onomique et en Foresterie Brazzaville Congo Ag.nce Nationale de la Valorisation des Résultats de la Recherche cité scientifique route de l’auberge de Gascogne Brazzaville Congo Ep.AN-Cong. P&#244le d’Excellence en Alimentation et Nutrition Faculté des Sciences et Techniques Université Marien NGOUABI Brazzaville Congo

In resp.nse to the malnutrition p.oblem affecting.children in Cong. Brazzaville, we made three cooking.typ. infant flours from Treculia obovoidea, Terminalia catap.a L. almonds and Ip.moea batatas L. leaves. The nutritional quality of the three infant flours we develop.d indicates 11.07% - 12.47% p.otein content, 9.92% - 14.87% fat content, 58.85% - 68.06% carbohydrate content, 1.50% - 2.18% ash and an energ. intake varying.between 399.84 and 439.37 Kcal. Functionally, our p.ep.red flours have a water absorp.ion cap.city between 219.05 and 317.86 mL/g. an oil absorp.ion cap.city of 0.19 mL/g. a water solubility index varying.from 29.66 - 41.03 and a swelling.cap.city of 250% - 320%.

关键词： p.ocess Formulation Infant Flours Terminalia catap.a Linne and Treculia obovoidea Almonds Ip.moea batatas Lam Leaves

Evaluation of p.tential Extracts Antioxydant (Aqueous, Hydro-Ethanolic and Ethanolic) of an Aquatic p.ant from the River Djoue (<i&g.;Ledermanniella schlechteri</i&g.;)

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Op.n Journal of Ap.lied Sciences 2021年第3期11卷 254-263页

作者： Roniche Ng.ie Tsiba g.uollaly Arnaud W. g. Tamba Somp.la J. E. Moussoung. M. g.det Dzondo N. p. g. p.mbou-Tobi p. Diakabana reyes H. g.mp.ula Centre de Recherche et d’Initiation des p.ojets de Technolog.e cité scientifique route de l’auberge de Gascogne Brazzaville Congo Ep.AN-Cong. P&#244 le d’Excellence en Alimentation et Nutrition Faculté des Sciences et Techniques Université Marien NGOUABI Brazzaville Congo Institut national de Recherche en Sciences de la Santé cité scientifique route de l’auberge de Gascogne Brazzaville Congo Unité de Chimie du Vég.tal et de la Vie FST-UMNG Brazzaville Congo Laboratoire de Biop.océdés alimentaires et médicaux ENSP-UMNG Brazzaville Congo Ecole Nationale Sup.rieure p.lytechnique (ENSp. Université Marien NGOUABI (UMNG) Brazzaville Congo Ecole Sup.rieure de Technolog.e des Cataractes Brazzaville Congo

The aim for this p.esent study was to evaluate the antioxidant p.tential of aqueous extracts (AE), hydro-ethanolic extracts (HE) and ethanolic extracts (EE) obtained from an aquatic p.ant (L. schlechteri) using.a simp.e and fast method that is the CCM. This method revealed the p.esence of p.enolics and flavonoids at different levels but with hig.er antioxidant activity in EE comp.red to AE. Among.the two families of antioxidants evaluated, the p.enolic comp.unds were found to be hig.er on the EE (5.85 mg.Ag.MS) followed by the HE (5.06 mg.Ag.MS) and less and less imp.rtant on the AE (3.661 mg.Ag.MS). While the less sig.ificantly elevated flavonoids showed values of 1.146 mg.Ca/MS for EE, 0.406 mg.Ca/MS for HE et 0.181 mg.Ca/MS for AE. However, the anti-free radical activity was also evaluated. Unlike the antioxidant activity, the ant-free radical activity with a g.eater IC50 was observed on AE with a rate of 66.66 mg.mL, then less on the hydro-ethanolic and ethanolic extracts, resp.ctively at levels of 26.15 mg.mL et 19.18 mg.mL.

关键词： Evaluation Antioxidant p.tential Extracts Aquatic p.ant Ledermanniella schlechteri

Using.music to reduce anxiety among.older adults in the emerg.ncy dep.rtment:a randomized p.lot study

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Journal of Integ.ative Medicine 2017年第6期15卷 450-455页

作者： Laura Belland Laura Rivera-reyes Ula Hwang center for family medicine newyork-presbyterian/columbia university medical centerNew YorkNY 10032USA dep.rtment of emerg.ncy medicine icahn school of medicine at mount sinaiNew YorkNY 10029USA g.riatric research education and clinical centerjames j.peters vamcNew YorkNY 10029USA

BACKg.OUND： An emerg.ncy dep.rtment （ED） visit may be distressing.and anxiety-p.ovoking.for older adults （ag. 〉 65 years）. No studies have sp.cifically evaluated the effect of music listening.on anxiety in older adults in the ED. OBJECTIVE： The objective of this p.lot study was to evaluate the effect of music listening.on anxiety levels in older ED p.tients. DESIg., SETTINg. p.RTICIp.NTS AND INTERVENTIONS： This was a randomized p.lot study in the g.riatric ED of an urban academic tertiary medical center. This was a samp.e of Eng.ish-sp.aking.adults （ag. 〉 65 years） who were not deaf （n = 35）. Subjects consented to p.rticip.te and were randomized to receive up.to 60 min of music listening.with routine care, while the control g.oup.received routine care with no music. Subjects in the music treatment g.oup.received headp.ones and an electronic tablet with p.e-downloaded music, and were allowed to choose from 5 selections. MAIN OUTCOME MEASURES： The p.imary outcome was chang. in anxiety levels, measured by the state- trait anxiety inventory （STAI）, at enrollment and 1 h later. RESULTS： A total of 35 p.rticip.nts were enrolled： 74% were female, 40% were white, and 40% were black; of these, 32 subjects comp.eted the study p.otocol. When comp.ring.control （n = 18） ag.inst intervention subjects （n = 17）, there were no sig.ificant differences in enrollment STAI scores （43.00 ± 15.00 vs. 40.30± 12.80, p.= 0.57）. STAI scores 1 hour after enrollment （after the music intervention） were sig.ificantly reduced in the intervention subjects comp.red to the control subjects （with reduction of 10.00± 12.29 vs. 1.88 ± 7.97, p.= 0.03）. CONCLUSION： These p.lot results sug.est that music listening.may be an effective tool for reducing.anxiety among.older adults in the ED.

关键词： music anxiety emerg.ncy dep.rtment randomized controlled trial

The Relative Imp.rtance of Natural Disturbances and Local Site Factors on Woody Veg.tation Reg.neration Diversity across a Larg., Contig.ous Forest Reg.on

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Op.n Journal of Forestry 2013年第3期3卷 88-98页

作者： g.rardo p. reyes Daniel Kneeshaw Louis de g.andp.é Dep.rtment of Biolog.cal Sciences Centre for Forest Research University of Quebec in Montreal Montreal Canada Dep.rtment of Biolog.cal Sciences Centre for Forest Research University of Quebec in Montreal Montreal Canada Faculty of Interdiscip.inary Studies Lakehead University Orillia Canada Dep.rtment of Biolog.cal Sciences Centre for Forest Research University of Quebec in Montreal Montreal Canada Natural Resources Canada Canadian Forest Service Laurentian Forestry Centre Ste-Foy Canada

Stand-level diversity after natural disturbance can p.tentially differ across a larg., contig.ous forest reg.on desp.te being.dominated by the same canop. sp.cies throug.out as differences in disturbance typ.s and local site conditions can reg.late sp.cies distribution. Our main objective was to examine the relative imp.rtance of natural disturbances (sp.uce budworm (Choristoneura fumiferana) outbreak, windthrow, and their interaction) and local site factors (climate, p.ysiog.ap.y, and stand structure and comp.sition variables) on woody veg.tation diversity among.three, p.ysiog.ap.ically distinct locations across a larg., contig.ous forest reg.on. Seventy-six Abies balsamea-Betula sp.. stands affected by natural disturbance were comp.red and analysed using.canonical ordination methods, diversity indices, and ANOVA. Different combinations of factors were imp.rtant for veg.tation re-establishment at each location. Differences in alp.a (α), beta (β), g.mma (γ), Shannon’s H’, and evenness (J) diversity indices were observed among.locations across the study reg.on. Our finding. indicate that while certain p.ocesses are imp.rtant for maintaining.canop. dominance by Abies balsamea and Betula sp.. throug.out the reg.on, different combinations of factors were imp.rtant for creating.variation in woody sp.cies diversity among.locations that resulted in g.eater woody sp.cies diversity at the reg.onal scale.

关键词： Reg.neration Natural Disturbance Environmental Factors Sp.cies Diversity Eastern Boreal Mixedwood Reg.on

Surrog.te Climate Chang. Scenario and p.ojections with a Reg.onal Climate Model: Imp.ct on the Aridity in South America

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American Journal of Climate Chang. 2014年第5期3卷 474-489页

作者： Serg.o H. Franchito Julio p. reyes Fernandez David p.reja Centro de p.evisao de Temp. e Estudos Climáticos CPTEC Instituto Nacional de Pesquisas Espaciais INPE C.P. 515 12201-970 Sao José dos Campos Brazil

The imp.ct of g.obal warming.on the aridity in South America (SA) is investig.ted. For this p.rp.se, the methodolog. for g.nerating.surrog.te climate-chang. scenarios with a RCM is emp.oyed. For the p.esent climate (CTRL) the RCM is initialized with and driven by ECMWF/ERA-Interim reanalysis data. Two aridity indices are used: the Budyko and the UNEp.indices. The results for the CTR are in ag.eement with other model studies which indicate future warming.rainfall increases in southeastern South America, Ecuador and p.ru and decreases in the central and eastern Amazon. In g.neral the model rep.oduces the aridity in the continent comp.red with the observed data for both indices. The distribution of aridity over SA in surrog.te climate-chang. scenario shows an increase of the dryness in the continent. Over Amazonia the aridity increases 23.9% (for the UNEp.index) and 3.1% (for the Budyko index), sug.esting.that p.rtions of the Amazonia forest are rep.aced by dry land area. The semi-arid zone over northeast Brazil exp.nds westward, attaining.the interior of north Brazil. In this reg.on the aridity increases 20% (for the UNEp.index) and 0.6% (for the Budyko index) indicating.that areas of humid reg.me may be occup.ed by areas with dry land reg.me. The RCM was also integ.ated driven by the AOg.M ECHAM5/Mp.-OM for the reference climate (CTRL2) and under A1B SRES scenario. The results for the p.esent-day climate are similar in CTRL2 and CTRL, and are in ag.eement with CRU data. The distribution of the aridity for the p.esent climate seems to be better rep.esented in CTRL using.both Budyko and UNEp.indices. The chang.s in aridity (future climate minus control) are hig.er in the run forced by the A1B SRES scenario. Althoug. the UNEp.and Budyko indices show p.tentialities and limitations to rep.esent the aridity distribution over SA, the chang.s in aridity due to a p.eudo-scenario of g.obal warming.are hig.er using.the UNEp.index.

关键词： Aridity in South America Surrog.te Climate-Chang. Scenario Reg.onal Climate Model