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Effects of a poly(hydroxyalkanoate)elastomer and kraft pulp fibres on biocomposite properties and three-dimensional(3D)printability of filaments for fused deposition modelling

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Journal of Bioresources and Bioproducts 2022年第3期7卷 161-172页

作者： Sandra rodríguez-Fabià Gary Chinga-Carrasco rISE PFI Høgskoleringen 6bTrondheim 7491Norway

Three-dimensional(3D)printing is a useful technique that allows the creation of objects with complex structures by deposition of successive layers of *** materials are often from fossil ***,efforts are being made to produce environmentally friendly materials for 3D *** addition of lignocellulosic fibres to a polymer matrix is one of the alternatives to replace,for instance,glass fibres in composites as reinforcing *** fields of biocom-posites and 3D printing open innovative application areas for pulp fibres from the pulp and paper *** this work,biocomposites of poly(lactic acid)(PlA),poly(hydroxyalkanoate)(PHA)and kraft pulp fibres were prepared in order to find a suitable formulation for filaments for 3D *** effect of two different types of kraft fibres(bleached(B)and unbleached(U))and of PHA on the mechanical and thermal properties of the biocomposites was *** addition of 30%kraft fibres to PlA resulted in an increase of the tensile modulus from 3074 to∼4800 *** the case of biocomposites containing PHA(50%PlA/20%PHA/30%kraft)the increase in modulus was more moderate(PlA+PHA+U:3838 MPa,and PlA+PHA+B:3312 MPa).The tensile strength of PlA(66 MPa)increased to 77 MPa in PlA+kraft biocomposites,while a reduc-tion in strength was observed for PlA+PHA+U(43 MPa)and PlA+PHA+B(32 MPa).Filaments prepared with PlA,PHA and bleached and unbleached pulp fibres showed similar printability of complex geometries,demonstrating that unbleached pulp fibres could also be utilized in the preparation of biocomposites with good mechanical performance and 3D printing properties.

关键词： biocomposites 3D printing Poly(lactic acid) Kraft pulp

Effect of relative humidity on the metabolite profiles,antioxidant activity and sensory acceptance of black garlic processing

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Food Bioscience 2022年第4期48卷 559-567页

作者： P.J.Gonzalez-ramírez l.I.Pascual-Mathey r.V.García-rodríguez ,M.Jimenez C.I.Beristain A.Sanchez-Medina l.A.Pascual-Pineda Instituto de Química Aplicada Universidad VeracruzanaAv.Dr.Luis Castelazo Ayala s/nCol.Industrial-AnimasC.P.91190XalapaVeracruzMexico Facultad de Química Farmaceutica Biologica Universidad VeracruzanaXalapaVeracruzMexico Centro de Investigacion y Desarrollo en Alimentos(CIDEA) Universidad VeracruzanaXalapaVeracruz91190Mexico

Fresh garlic(FG)was processed at five different relative humidities(rH)at 55◦C for 40 *** moisture content,aw,browning intensity and DPPH scavenging capacity were determined during processing under controlled *** processing,sensory acceptance and metabolite differences were analyzed using ***,a chemometric analysis was performed using both the 1H-NMr chemical profiles and the sensory evaluation of the 40-day black garlic(BG)*** increase in the antioxidant capacity at higher browning rate was *** variability for twenty-five compounds showed main changes in amino and organic acids,sugars,organosulfur compounds,ethanol,methanol GABA,choline and *** acceptance values on the sensory evaluation were for BG processed at 58 and 71%rH,indicating that intermediates rH results in a better sensory *** OPlS-DA chemometric analysis showed that sugars,formic acid,5-HMF,amino acids,ethanol,and choline were the main contributors.

关键词： Black garlic processing Antioxidant activity Chemical profile Sensory evaluation Chemometrics OPlS

X-ray diffraction analysis by rietveld refinement of FeAl alloys doped with terbium and its correlation with magnetostriction

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Journal of rare Earths 2023年第8期41卷 1217-1224,I0004页

作者： J.S.Uribe-Chavira G.Herrera-Pérez C.r.Santillán-rodríguez r.J.Sáenz-Hernández J.A.Matutes-Aquino M.C.Grijalva-Castillo Materials Physics Department Centro de Investigación en Materiales AvanzadosS.C.Miguel de Cervantes 120Chihuahua31136ChihMexico CONACYT–Centro de Investigación en Materiales Avanzados S.C.Miguel de Cervantes 120Chihuahua31136ChihMexico

Fe_(81)Al_(19) polycrystalline alloys doped with Tb(0-0.25 at%) were obtained by arc *** introduction of Tb favors the formation of columnar grains in the micro structure of the alloys,which develops a texture in the [100]crystal *** examination shows that the alloys are composed in great proportion by the disordered body-centered cubic(bcc),A2 phase and by a small proportion of the ordered bcc,B2 *** a consequence of doping with Tb,the lattice parameter increases,so the calculated apparent crystallite size increases,indicating a decrease in dislocation density and therefore in *** change in the magnetostriction with the magnetic field,dλ_(T)/dH,is directly related to strain anisotropy that can favor the iron easy magnetization axis on the [100] *** increase in total magnetostriction is found in the doped alloys with a maximum of 90 × 10^(-6) at 300 K for the alloy containing 0.027 at% *** enhancement is a threefold value of the undoped alloy,which is attributed to the smaller maximum strain value and the preferential orientation formation by the columnar grains.

关键词： FeAl alloy Magnetostriction rietveld refinement Microstrains Preferred orientation rare earths

liquid-liquid interfacial tension of equilibrated mixtures of ionic liquids and hydrocarbons

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Science China Chemistry 2012年第8期55卷 1519-1524页

作者： rodríguez Héctor ArCE Alberto SOTO Ana Department of Chemical Engineering University of Santiago de Compostela E-15782 Santiago de Compostela Spain

Ionic liquids are possible alternative solvents for the separation of aromatic and aliphatic hydrocarbons by liquid-liquid extrac- tion. Interfacial tension is an important property to consider in the design of liquid-liquid extraction processes. In this work, the liquid-liquid interfacial tension and the mutual solubility at 25 ℃ have been measured for a series of biphasic, equilibrated mixtures of an ionic liquid and a hydrocarbon. In particular, the ionic liquids 1-alkyl-3-methylimidazolium bis（trifluorome- thanesulfonyl）imide （with the alkyl substituent being ethyl, hexyl or decyl）, 1-ethyl-3-methylimidazolium ethylsulfate, and 1-ethyl-3-methylimidazolium methanesulfonate have been selected, as well as the hydrocarbons benzene, hexane, ethylben- zene, and octane. The selected sets of ionic liquids and hydrocarbons allow the analysis of the influence of a series of effects on the interfacial tension. For example, the interfacial tension decreases with an increase in the length of the alkyl substituent chain of the cation or with an increase of the degree of charge delocalisation in the anion of the ionic liquid. Also, the interfa- cial tension with the aromatic hydrocarbons is markedly lower than that with the aliphatic hydrocarbons. A smaller effect is caused by variation of the size of the hydrocarbon. Some of the observed trends can be explained from the mutual solubility of the hydrocarbon and the ionic liquid.

关键词： ionic liquid aromatic hydrocarbon aliphatic hydrocarbon interfacial tension liquid-liquid equilibrium

Weak crossed biproducts and weak projections

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Science China Mathematics 2012年第7期55卷 1321-1352页

作者： FErNNDEZ VIlABOA Jose Manuel GONZlEZ rodríguez ramon rodríguez rAPOSO Ana Belen Departamento de lxebra Universidad de Santiago de Compostela Departamento de Matemtica Aplicada II Universidade de Vigo Departamento de Matemticas Universidade da Coruna

In this paper, we present the general theory and universal properties of weak crossed biproducts. We prove that every weak projection of weak bialgebras induces one of these weak crossed structures. Finally, we comput... 详细信息

关键词： braided monoidal category preunit crossed product weak Hopf algebra weak projection weakcrossed biproduct

The Drying of Pyridine Hydrobromide

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Chinese Journal of Chemical Engineering 1998年第2期6卷 76-80页

作者： renéD.Peralta rodríguez raúl G.lópez Campos Jaime Wisniak Jacinto G.rodríguez Gómez Silvia Torres rincón M.Esther Treviño Martínez Centro de Investigacion en Quimica Aplicada Blvd.Ing.Enrique Reyna Hermosillo No.140C.P.25100SaltilloCoahuilaMexico Department of Chemical Engineering Ben-Gurion University of the NegevBeer-ShevaIsrael

1 INTrODUCTIONThe drying of fine chemicals and pharmaceuticals is dominated by a number of special factorscompared to the drying of bulk *** include:very high value of product;lowthroughputs(typically,100 kg·hsup>-1sup>);materials that frequently possess toxic properties andare often sticky,pasty and difficult to handle when wet;the moisture to be evaporated ofteninvolves solvents;and multipurpose processing plants.

关键词： drying pyridine hydrobromide

Pisco grape pomace:Iron/copper speciation and antioxidant properties,towards their comprehensive utilization

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Food Bioscience 2022年第3期47卷 1213-1221页

作者： Fátima rodríguez-ramos raúl Cañas-Sarazúa Vilbett Briones-labarca Departamento de Ingeniería en Alimentos Universidad de La SerenaAv.Raúl Bitrán Nachary 1305Box 5991720010La SerenaChile

The pisco and wine industry produces hundreds of tons of grape pomace each year in Chile,generating environmental problems,and demanding urgent strategies for its *** aim of this work was to study the pisco grape pomace based on a physicochemical characterization,an iron/copper speciation analysis,and the optimization for polyphenols recovery,establishing the polyphenolic profile,antioxidant properties,and the Fe^(2+)/Cu^(2+) chelating activity,to promote their revalorization as an ingredient with potential application in the food *** chemical characterization showed mainly high values for crude protein(15.36%dw)and potassium(9240.66 mg/kg).The Fe/Cu speciation depicted that iron and copper soluble forms in pisco pomace flour represented 70.57%and 52.18%,respectively,regarding total *** optimized extract showed mainly pyrogallol,catechin and epicatechin,with concentrations of 1078.43±60.14μg/g,883.20±7.57μg/g and,751.76±23.04μg/g,respectively,with a relevant antioxidant capacity by Oxygen radical Absorbance Capacity(OrAC)of 1402.15μmol TE/g dw GPE and,a better chelating ability to complex Fe^(2+) than Cu^(2+).The pisco pomace was for the first time chemically characterize,showing it as a potential source of minerals and antioxidant biocompounds,making it a good candidate for nutritional applications,as a rich source of organic matter or even could be potentially utilized to produce value-added commodities,toward a circular economy.

关键词： Pisco grape pomace Polyphenols Chemical speciation analysis Antioxidant capacity Metal chelating ability

Deadly oasis:recurrent annihilation of Cretaceous desert bryophyte colonies;the role of solar,climate and lithospheric forcing

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Geoscience Frontiers 2021年第1期12卷 1-12页

作者： Juan Pedro rodríguez-lópeza Eduardo Barrón Daniel Peyrot Gary B.Hughes Department of Geology.Faculty of Science.United Arab Emirates University.50009.Al Ain Abu DhabiUnited Arab Emirates Instituto Geológico y Minero de Espana(IGME) Ríos Rosas 23E-28003MadridSpain School of Earth and Environment University of Western Australia.6101CrawleyWestern AustraliaAustralia Centre for Energy Geosciences University of Western Australia.6101CrawleyWestern AustraliaAustralia Physics Department University of CaliforniaSanta BarbaraCA93106USA

Many oases(wet interdunes)are sedimentary systems characterized by high-frequency water-level oscillations,marked changes in salinity and intense biological activity at their *** are considered to be one of the most challenging environments on Earth for ecosystem *** dynamic,depositional settings are usually unfavourable for fossilization and subsequent preservation of vegetal *** paper describes bryophyte(liverwort)assemblages occurring in three successive horizons interpreted to represent(i)recurrent early successional phases of biological soil crust colonization of wet interdune margins or(ii)exceptional preservation of floating or riparian liverworts in oasis pond waters associated with a progressive fall of the interdune water *** record of in situ colonization surfaces characterized by delicate(***-free)three-dimensional structures represents an exceptional type of preservation herein associated with a rapid variation in phreatic interdune water level and the subsequent establishment of anoxic and reducing *** occurrence of exceptionally preserved liverwort colonies coincides with the sedimentary record of,at least,three seismite levels in the *** gathered from the site suggests that the water table of the oasis was controlled by a combination of(i)a positive creation of accommodation space due to subsidence associated with movement on syn-sedimentary extensional faults,and(ii)the rise and fall of the oasis water table controlled by the oscillations of the groundwater system due to orbital changes which appear to drive the variability of the climate *** groundwater levels flooded the oasis soil crusts and lead to the exceptional recurrent preservation of liverwort colonies at the oasis ***,considering the hypothesis of floating or riparian liverworts in the oasis pond waters,the fall in the level of the oasis water table placed the floating liverworts in contact with the

关键词： Oasis Cretaceous liverworts Colonies Extensional tectonics Solar cyclicity

Toxicity of Mexican native plant extracts against larvae of Aedes aegypti(Diptera: Culicidae)

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Asian Pacific Journal of Tropical Biomedicine 2015年第4期5卷 287-291页

作者： rosario ruiz-Guerrero Mario Alberto rodríguez-Pérez Mariano Norzagaray-Campos CIITEC-IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco Centro de Biotecnología Genómica-IPN Blvd. Del Maestro S/N Colonia Narciso Mendoza CIIDIr-IPN-Sinaloa Bulevar Juan de Dios Bátiz Paredes No 250 Colonia San Joachin. Guasave

Objective: To evaluate five indigenous Mexican plants [Hippocratea excelsa, Hippocratea celastroides, Argemone mexicana(A. mexicana), Tagetes lucida, and Pseudosmodingium perniciosum(P. perniciosum)] toxicity against the fourth instar larvae of the dengue primary vector, Aedes aegypti(A. aegypti).Methods: Each plant part was treated successively with hexane, ethyl acetate, acetone, and methanol to extract potential active components of the plants against the dengue ***: There was a range of toxicity at 24 or 48 h post-exposure for the different plant parts and organic solvent used(lC50 values ranged between 20 and 890 μg/ml). Extracts from seeds of A. mexicana(hexane washing with methanol and acetone) and stem-bark of P. perniciosum(hexane) showed highest toxicity to Ae. aegypti larvae at 48 h post-exposure(lC50 values were80, 50, and 20 μg/ml, respectively), thus making them potential candidates as *** are on-going to characterize the bioactive components of the extracts, through chromatography, for their use as biological tools for the control of the primary dengue ***: A. mexicana and P. perniciosum are good candidates to combat the dengue vector, Ae. aegypti, as they were highly toxic to the larvae.

关键词： Aedes aegypti Dengue larvicidal activity Plant organic extracts