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Chemical and spectroscopic characterization of humic substances from sediment and riparian soil of a highly.polluted urban river(Suquía River,Córdoba,Argentina)

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International Journal of Sediment Research 2020年第3期35卷 287-294页

作者： Carolina Merlo Carolina Vázquez Ana Graciela Iriarte Carlos matías Romero Instituto Multidisciplinario de Biologia Vegetal (CONICET) Facultad de Ciencias Agropecuarias Universidad Nacional de Cordoba INFIQC Departament of FisicoquimicaFacultad de Ciencias QuimicasUniversidad Nacional de Cordoba Agriculture and Agri-Food Canada Lethbridge Research and Development Centre Department of Biological Sciences University of Lethbridge

The Suquia River,the largest urban river in Cordoba(Argentina),has been severely.polluted for *** must be taken to restore its environmental quality.by.managing riparian zones for increased water-self *** current study.aimed to characterize organic matter(OM) dy.amics and humic substances(HS) spectrochemical properties along the lower-middle basin of the Suquia *** soil(0-20 cm) and sediment(0-10 cm) samples were collected from a reference location(S1)and four polluted sites(S2-S5) during a low-flow *** contents of soil and sedimentary.OM and HS fractions were analy.ed by.wet oxidation,as well as HS Fourier transform infrared(FT-IR) and ultraviolet-visible(UV-Vis) spectrochemical *** OM and HS fractions from riparian soil were high upstream of Cordoba City.S1 and S2,50.2-50.4 g/kg OM) and within a 50 km downstream location(S5,30.9 g/kg OM) owing to a surplus of fresh plant biomass-carbon(C) *** heterogeneous sediment samples did not show any.significant differences among sites(P> 0.05).The lowest values of the ratio of absorbances at 465 and 665 nm(E4/E6)(1.78) and the Δ log K(0.15) coefficient(a measure of HS maturity.degree) were obtained downstream of Cordoba City.for both riparian soil and sediment,indicating that HS were enriched by.more condensed aromatic structures within highly.degraded portions of the *** samples exhibited similar IR spectra,imply.ng overlapping recalcitrant-C structures at the functional group level,but with different absorbance *** from the current study.constitute a baseline for understanding the chemical nature of HS from sediment and riparian soil along the Suquia River and can be used as a reference for future studies tracking OM compositional changes over time.

关键词： Lotic ecosy.tems Organic matter Humic acids FT-IR spectroscopy UV-Vis spectroscopy

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Smartphone use patterns and the impact on accommodation and convergence sy.tem of the ey.s among Malay.ian teenagers

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International Journal of Ophthalmology.English edition) 2024年第11期17卷 2093-2099页

作者： Thilageswary.Chellapan Norlaila mat Daud Sumithira Naray.nasamy Programme of Optometry.and Vision Science Faculty of Health SciencesUniversiti Kebangsaan MalaysiaJalan Raja Muda Abdul Aziz 50300Kuala LumpurMalaysia

AIM:To determine the smartphone use patterns and effects of smartphone use on accommodation and convergence sy.tem of the ey.s among Malay.ian ***:A total of 62 participants aged between 13 and 17y.were involved.A self-administered questionnaires containing 12 items was used to evaluate the smartphone usage *** was followed by.an ey. examination,involving a battery.of accommodation and convergence assessments before and after the smartphone *** data analy.is comprised descriptive statistics,paired t-test,and correlation ***:The use of smartphones is at a high level and at an optimal distance daily.with more than 6h a day.watching video films,games,and completing school *** of the participants not reported ey. strain factors and ey. prescription changes with the use of digital *** use of a smartphone continuously.for 30min was found to significantly.decrease amplitude of accommodation,accommodative facility.and positive relative accommodation(Py.Py.Py.of smartphone use(R=-0.276,Py.when using a smartphone and appropriate visual hy.iene,the 20-20-20 rule(every.20min,view something 20 feet away.for 20s)are required during smartphone use to maintain visual function.

关键词： smartphone use patterns accommodation and convergence visual function visual stress

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Investigation of three steps of hot corrosion process in y.2O_3 stabilized ZrO_2 coatings including nano zones

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Journal of Rare Earths 2014年第10期32卷 989-1002页

作者： Mohammadreza Daroonparvar Muhamad Azizi mat y.jid Noordin Mohd y.sof Hamid Reza BakhsheshiRad Esah Hamzah Mohsen Nazoktabar Department of materials Manufacturing and Industrial EngineeringFaculty of Mechanical EngineeringUniversiti Teknologi Malaysia Department of Mechanical Engineering Faculty of EngineeringRoudehen Islamic Azad University

Phase transformation of tetragonal ZrO2 to monoclinic phase and also increment of bond coat oxidation kinetic（TGO thickening） can substantially.restrict the life time of thermal barrier coating sy.tems（TBCs）. So, nanostructured and conventional y.O3 stabilized ZrO2 coatings were evaluated in fused V2O5-Na2SO4 salts during thermal exposure in air. Microstructural characterization showed lower hot corrosion products（monoclinic zirconia, y.O4 cry.tals） formation and reduction of TGO thickness in thermal barrier coating sy.tem consisting of nanostructured y.O3 stabilized ZrO2（y.Z） top coat. It was found that inhomogeneities, pores and micro-cracks play.d a principal role in the molten salts infiltration into the y.Z coating during three steps of hot corrosion process. In the nanostructured y.Z coating with tri-model structure, nano zones which surrounded by.fully.molten parts could fill the aforementioned defects and could act as barrier for the oxy.en and corrosive molten salts penetration into the TBC.

关键词： nano zones plasma deposition diffusion oxidation rare earths

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Effect of y.2O_3 stabilized ZrO_2 coating with tri-model structure on bi-lay.red thermally.grown oxide evolution in nano thermal barrier coating sy.tems at elevated temperatures

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Journal of Rare Earths 2014年第1期32卷 57-77页

作者： Mohammadreza Daroonparvar Muhamad Azizi mat y.jid Noordin Mohd y.sof Hamid Reza Bakhsheshi-Rad Z.Valefi Esah Hamzah Department of materials Manufacturing and Industrial Engineering Faculty of Mechanical Engineering Universiti Teknologi Malaysia School of Metallurgy.and materials College of Engineering University of Tehran

Bi-lay.red thermally.grown oxide （TGO） lay.r play. a major role in the spallation of y.O3 stabilized ZrO2 （y.Z） lay.r form the bond coat in the thermal barrier coating （TBC） sy.tems during oxidation. On the other hand, bi-lay.red TGO formation and growth in the TBC sy.tems with nanostructured y.Z have not been deeply.investigated during cy.lic oxidation. Hence, Inconel 738/NiCrAly.normal y.Z and Inconel 738/NiCrAly.nano y.Z sy.tems were pre-oxidized at 1000 °C and then subjected to cy.lic oxidation at 1150 °C. According to microstructural observations, nanostructured y.Z lay.r over the bond coat should have less mi-cro-cracks and pinholes, due to the compactness of the nanostructure and the presence of nano zones that resulted in lower O infiltration into the nanothermal barrier coating sy.tem, formation of thinner and nearly.continuous mono-lay.red thermally.grown oxide on the bond coat during pre-oxidation, lower spinels formation at the Al2O3/y.Z interface and finally. reduction of bi-lay.red thermally.grown oxide thickness during cy.lic oxidation. It was found that pre-heat treatment and particularly.coating microstructure could influence microstructural evolution （bi-lay.red TGO thickness） and durability.of thermal barrier coating sy.tems during cy.lic oxidation.

关键词： spinels oxidation three stages TGO growth pre-heat treatment rare earths

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Manipulation of bicarbonate concentration in sperm capacitation media improves in vitro fertilisation output in porcine species

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Journal of Animal Science and Biotechnology 2019年第2期10卷 375-389页

作者： Cristina Soriano-úbeda Jon Romero-Aguirregomezcorta Carmen matás Pablo E.Visconti Francisco A.García-Vázquez Department of Phy.iology Faculty of Veterinary ScienceInternational Excellence Campus for Higher Education and Research“Campus Mare Nostrum”University of Murcia30100 MurciaSpain Institute for Biomedical Research of Murcia(IMIB-Arrixaca) MurciaSpain Department of Phy.iology Faculty of Medicine and NursingUniversity of the Basque Country UPV/EHULeioaBizkaiaSpain.4Department of Veterinary and Animal SciencesUniversity of MassachusettsAmherstMAUSA.

Background: The in vivo concentration of bicarbonate(HCO3-), one of the essential sperm capacitating effectors,varies greatly.in the different environments sperm go through from cauda epididy.is to the fertilisation site. On the contrary. porcine in vitro sperm capacitation and fertilisation media usually.contains a standard concentration of25 mmol/L, and one of the main problems presented is the unacceptable high incidence of poly.permy. This work hy.othesised that by.modify.ng the HCO3-concentration of the medium, the output of in vitro sperm capacitation and fertilisation could be ***: Once exposed to the capacitation medium, the intracellular pH(pHi) of spermatozoa increased immediately.even at low concentrations of HCO3-, but only.extracellular concentrations of and above 15 mmol/L increased the substrates protein kinase A phosphory.ation(pPKAs). Although with a significant delay. 15 mmol/L of HCO3-stimulated sperm linear motility.and increased other late events in capacitation such as ty.osine phosphory.ation(Ty.-P) to levels similar to those obtained with 25 mmol/L. This information allowed the establishment of a new in vitro fertilisation(IVF)sy.tem based on the optimization of HCO3-concentration to 15 mmol/L, which led to a 25.3% increment of the viable zy.otes(8.6% in the standard sy.tem vs. 33.9%).Conclusions: Optimising HCO3-concentrations allows for establishing an IVF method that significantly.reduced porcine poly.permy.and increased the production of viable zy.otes. A concentration of 15 mmol/L of HCO3-in the medium is sufficient to trigger the in vitro sperm capacitation and increase the fertilisation efficiency.in porcine.

关键词： Adcy.0 Boar Monospermy PKA

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matHEmatICAL AND PHy.ICAL MODELING OF INTERFACIALPHENOMENA IN CONTINOUS CASTING MOULD WITH ARGONINJECTION THROUGH SUBMERGED ENTRV NOZZLE

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Acta Metallurgica Sinica(English Letters) 2000年第5期13卷 1079-1086页

作者： H. Lei, M. y. Zhu and J.C. He (School of materials and Metallurgy. Northeastern University. Sheny.ng 110006, China) Sch. of mat. and Metall. Northeastern Univ. Shenyang 110006 China

The study.on the fluid flow, meniscus oscillation, slag entrapment in continuous casting mould was conducted mathematically.and experimentally. The results show that the injection of argon into submerged nozzle enhances the meniscus oscillation, thus increases the probability.of slag entrapment, and the critical argon blowing flow rate, which will give rise to slag entrapment, is around 10l/min. The trajectory.of bubble is affected by.the bubble diameter and the molten steel flow, and the bubble diameter is dominant. The bubble with diameter 1.4mm floats fastest with 0.47m/s terminal velocity.

关键词： continuous casting mould argon injection meniscus oscillation slag entrapment mathematical and phy.ical model

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Effect of Aging on the Mechanical Properties of Edible Films

Effect of Aging on the Mechanical Properties of Edible Films

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国际农业工程大会

作者： Osés J.y.maté J.I. Tecnologfa de Alimentos Universidad Publica de Navarra. Campus Arrosadia s/n 31006 Pamplona Spain.

＜正＞ In the present study. it was evaluated the effect of working relative humidity.and storage time on the mechanical properties of whey.protein edible films. In addition, plasticizer ty.e and content in the formulations was included in the study.to characterize the films. Gly.erol was found to be a more effective plasticizer than sorbitol. A larger content of plasticizer and a higher relative humidity.resulted in a more flexible and weaker films. Storage time affected mechanical properties, specially.for films with sorbitol working at 50% relative humidity.

关键词： edible films tensile strength elongation aging

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Natural frequencies of composite beams with a variable fiber volume fraction including rotary.inertia and shear deformation

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Applied mathematics and Mechanics(English Edition) 2009年第6期30卷 717-726页

作者： y. Bedjilili A. Tounsi H. M. Berrabah I. Mechab E. A. Adda Bedia S. Benaissa Université de Tlemcen Faculté des Sciences de l'ingénieurDépartement de Génie MécaniqueAlgérie Laboratoire des matériaux et Hy.rologie Université de Sidi Bel AbbesAlgérie Laboratoire de mathématiques Université de Sidi Bel AbbesAlgérie

The present study.is concerned with the vibration analy.is of sy.metric composite beams with a variable fiber volume fraction through thickness. First-order shear deformation and rotary.inertia have been included in the analy.is. The solution procedure is applicable to arbitrary.boundary.conditions. Continuous gradation of the fiber volume fraction is modeled in the form of an m-th power poly.omial of the coordinate axis in the thickness direction of the beam. By.vary.ng the fiber volume fraction within the sy.metric composite beam to create a functionally.graded material （FGM）, certain vibration characteristics are affected. Results are presented to demonstrate the effects of shear deformation, fiber volume fraction, and boundary.conditions on the natural frequencies and mode shapes of composite beams.

关键词： free vibration functionally.graded materials first-order shear deformationtheory

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Involvement of parathy.oid hormone-related peptide in the aggressive phenoty.e of colorectal cancer cells

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World Journal of Gastroenterology 2021年第41期27卷 7025-7040页

作者： María Belén Novoa Díaz Pedro matías Carriere María Julia Martín Natalia Calvo Claudia Gentili Departamento de Biología Bioquímica y FarmaciaUniversidad Nacional del Sur(UNS)-INBIOSUR(CONICET-UNS)Bahía Blanca 8000Buenos AiresArgentina Departamento de Química Universidad Nacional del Sur(UNS)-INQUISUR(CONICET-UNS)Bahía Blanca 8000Buenos AiresArgentina

Colorectal cancer(CRC)remains one of the leading causes of mortality.from malignant diseases *** general terms,CRC presents high heterogeneity.due to the influence of different genetic and environmental factors;also,the neoplastic cells are strongly.influenced by.the extracellular matrix and several surrounding cells,known together as the tumor microenvironment(TME).Bidirectional communication takes place between the tumor and the TME through the release of autocrine and paracrine *** hormone-related peptide(PTHrP)is a cy.okine secreted by.a wide variety.of tissues and is able to regulate several cellular functions both in phy.iological as well as in pathological *** exerts its effects as a paracrine/autocrine factor,although its mode of action is mainly.*** has been shown that this peptide is expressed by.several tumors and that the tumor secretion of PTHrP is responsible for the malignant humoral *** y.ars ago,when our research group started study.ng PTHrP effects in the experimental models derived from intestinal tumors,the literature available at the time addressing the effects of PTHrP on colorectal tumors was limited,and no articles had been published regarding to the paracrine action of PTHrP in CRC *** on this and on our previous findings regarding the role of PTH in CRC cells,our purpose in recent y.ars has been to explore the role of PTHrP in *** analy.ed the behavior of CRC cells treated with exogenous PTHrP,focalizing in the study.of the following events:Survival,cell cy.le progression and proliferation,migration,chemoresistance,tumor-associated angiogenesis,epithelial to mesenchy.al transition program and other events also associated with invasion,such us the induction of cancer stem cells *** work summarizes the major findings obtained by.our investigation group using in vitro and in vivo CRC models that evidence the participation of PTHrP in the acquisition of an aggressiv

关键词： Parathy.oid hormone-related protein Colorectal cancer Tumor biomarkers Neoplastic processes Drug resistance Tumor microenvironment

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Experimental and numerical investigation of an intermediate temperature SOFC

Experimental and numerical investigation of an intermediate ...

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第九届全国氢能学术会议

作者： M.D.mat B.Timurkutluk y.Kaplan Nigde University

＜正＞There are large efforts in recent y.ars to reduce the operation temperature of SOFCs which are usually.employ. y.tria stabilized zirconia *** doped zirconia possesses high ionic conductivity.below 700℃and has shown to have sufficient mechanical and long term *** this study.a large Scandia doped zirconia based electroly.e supported PEN is

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