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Zeolite-templated carbons as effective sorbents to remove methylsiloxanes and derivatives:A computational screening

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Green Energy & Environment 2021年第6期6卷 884-892页

作者： Shiru Lin Kaitlyn A.Jacoby Jinxing Gu Dariana R.vega-Santander Arturo J.Hernaandez-Maldonado Zhongfang Chen Department of Chemistry University of Puerto RicoRío PiedrasSan JuanPR 00931USA Department of Chemistry&Biochemistry Elizabethtown CollegeElizabethtownPA 17022USA Department of Chemical Engineering University of Puerto RicoMayaguez CampusMayaguezPR 00681USA

Though widely used in our daily lives,volatile methylsiloxanes and derivatives are emerging contaminants and becoming a high-priority environment and public health *** effective sorbent materials can remove siloxanes in a cost-effective ***,by means of Grand Canonical Monte Carlo(GCMC)simulations,we evaluated the potentials of the recently proposed 68 stable zeolite-templated carbons(ZTCs)(PNAS 2018,115,E8116-E8124)for the removal of four linear methylsiloxanes and derivatives as well as two cyclic methylsiloxanes by the calculated average loading and average adsorption energy *** ZTCs,namely ISV,FAU1,FAU3,and H8326836,were identified with the top 50%adsorption performance toward all the six targeted contaminants,which outperform activated *** first principles computations revealed that steric hindrance,electrostatic interactions(further enhanced by charge transfer),and CH-p interactions account for the outstanding adsorption performance of these *** work provides a quick procedure to computationally screen promising ZTCs for siloxane removal,and help guide future experimental and theoretical investigations.

关键词： Zeolite-templated carbons Contaminants of emerging concern Methylsiloxanes GCMC simulations Density functional theory calculations

Using density functional calculations to elucidate atomic ordering of Pd-Rh nanoparticles at sizes relevant for catalytic applications

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Chinese Journal of Catalysis 2019年第11期40卷 1749-1757页

作者： Lorena vega Hristiyan A.Aleksandrov Konstantin M.Neyman Departament de Ciència dels Materials i Química Física&Institut de Química Teòrica i Computacional Universitat de Barcelona08028 BarcelonaSpain Faculty of Chemistry and Pharmacy University of Sofia1126 SofiaBulgaria InstitucióCatalana de Recerca i Estudis Avan?ats(ICREA) 08010 BarcelonaSpain

Pd-Rh nanoparticles are known to easily undergo surface restructuring in reactive environment. This study quantifies, with the help of density functional(DFT) calculations and a novel topological approach, atomic ordering and surface segregation effects in Pd-Rh particles with compositions 1:3, 1:1 and 3:1 containing up to 201 atoms(ca. 1.7 nm). The obtained data are used to reliably optimise energetically preferred atomic orderings in inaccessible by DFT Pd-Rh particles containing thousands of atoms and exhibiting sizes exceeding 5 nm, which are typical for catalytic metal particles. It is outlined, how segregation effects on the surface arrangement of Pd-Rh nanoalloy catalysts induced by adsorbates can be evaluated in a simple way within the present modelling setup.

关键词： Density functional calculations Atomic ordering Pd Rh nanoparticles Size relevant

Nitrate Transport, Sensing, and Responses in Plants

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Molecular Plant 2016年第6期9卷 837-856页

作者： Jose A. O'Brien Andrea vega Eleonore Bouguyon Gabriel Krouk Alain Gojon Gloria Coruzzi Rodrigo A. Gutierrez Departamento de Genetica Molecular y Microbiologia FONDAP Center for Genome Regulation Millennium Nucleus Center for Plant Systems and Synthetic Biology Pontificia Universidad Cat61ica de Chile 8331150 Chile Departamento de Fruticultura y Enologia Pontificia Universidad Catolica de Chile Santiago 7820436 Chile Departamento de Ciencias Vegetales Pontificia Universidad Catolica de Chile Santiago 7820436 Chile Department of Biology Center for Genomics and Systems Biology New York University New York NY 10003 USA SLaboratoire de Biochimie et Physiologie Moleculaire des Plantes Institut de Biologie Integrative des Plantes 'Claude Grignon' UMR CNRS INRA SupAgro UM 2 Place Viala 34060 Montpellier Cedex France

Nitrogen （N） is an essential macronutrient that affects plant growth and development. N is an important component of chlorophyll, amino acids, nucleic acids, and secondary metabolites. Nitrate is one of the most abundant N sources in the soil. Because nitrate and other N nutrients are often limiting, plants have developed sophisticated mechanisms to ensure adequate supply of nutrients in a variable environment. Nitrate is absorbed in the root and mobilized to other organs by nitrate transporters. Nitrate sensing activates signaling pathways that impinge upon molecular, metabolic, physiological, and developmental responses locally and at the whole plant level. With the advent of genomics technologies and genetic tools, important advances in our understanding of nitrate and other N nutrient responses have been achieved in the past decade. Furthermore, techniques that take advantage of natural polymor- phisms present in divergent individuals from a single species have been essential in uncovering new components. However, there are still gaps in our understanding of how nitrate signaling affects biolog- ical processes in plants. Moreover, we still lack an integrated view of how all the regulatory factors iden- tified interact or crosstalk to orchestrate the myriad N responses plants typically exhibit. In this review, we provide an updated overview of mechanisms by which nitrate is sensed and transported throughout the plant. We discuss signaling components and how nitrate sensing crosstalks with hormonal pathways for developmental responses locally and globally in the plant. Understanding how nitrate impacts on plant metabolism, physiology, and growth and development in plants is key to improving crops for sustainable agriculture.

关键词： nitrate nitrate transporters hormones N-foraging

Rice Husk Bio-Chars as Adsorbent for Methylene Blue and Ethinylestradiol from Water

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Journal of Renewable Materials 2020年第3期8卷 275-287页

作者： Jonathan Lacuesta Iris Beatriz vega Erramuspe Liji Sobhana Dennis Kronlund Jouko Peltonen Soledad Gutiérrez Pedro Fardim Department of Chemical Engineering University of the RepublicJulio Herrera y Reissig 565Montevideo11300Uruguay Laboratory of Fibre and Cellulose Technology Åbo Akademi UniversityPorthansgatan 3Turku/ÅboFI-20500Finland Laboratory of Physical Chemistry and Center of Excellence for Functional Materials Åbo Akademi UniversityPorthansgatan 3Turku/ÅboFI-20500Finland Department of Chemical Engineering KU LeuvenCelestijnenlaan 200FLeuvenB-3001Belgium

Biobased adsorbents are eco-friendly materials used for water and wastewater treatment and air *** research work explores the potential use of rice husk chars as a low-cost adsorbent for pollutants from water,such as methylene blue and *** husk chars are prepared by combustion of rice husks(RH-Char)or pre-treated rice husks(PT-Char).A third char(M-Char)supplied by a local company which uses rice husks as combustion material is also *** chars are characterized by field emission scanning electron microscopy(FE-SEM)in conjunction with energy dispersive X-ray spectroscopy(EDX),X-ray powder diffraction(XRD),and zeta-potential *** three bio-chars are tested as adsorbent for the removal of two wastewater contaminants:methylene blue(MB)and ethinylestradiol(EE2).According to the results,RH-Char and PT-Char present zeta-potential values near−52 mV,whereas M-Char shows a zeta-potential value of−32 *** RH-Char and PTChar are rich in amorphous SiO_(2) and M-Char has crystalline SiO_(2)(cristobalite).The bio-chars remove MB and EE2 efficiently showing the following results for the adsorption capacity of MB(inμmol g^(−1)):769.2(RH-Char),41.2(PT-Char),and 31.7(M-Char).The adsorption capacity values for EE2(inμmol g^(−1))are:33.1(RH-Char),19.1(PT-Char),and 16.9(M-Char).The information gathered in the present work evidences the potential of rice husks bio-chars for bio-remediation and may in future contribute to the conversion of a side-stream from the rice industry into value-added materials.

关键词： Rice husk bio-char thermal treatment adsorption methylene blue ethinylestradiol

Drought and Spatiotemporal Variability of Forest Fires Across Mexico

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Chinese Geographical Science 2018年第1期28卷 25-37页

作者： Pompa-García MARíN Camarero J.JULIO Rodríguez-Trejo DANTE ARTURO vega-Nieva DANIEL JOSE Facultad de Ciencias Forestales Universidad Juarez del Estado de Durango Durango 34120 MExico Instituto Pirenaico de Ecologia IPE-CSIC 50059 Spain Divisian de Ciencias Forestales Universidad Autonoma Chapingo Chapingo 56230 MExico

Understanding the spatiotemporal links between drought and forest fire occurrence is crucial for improving decision-making in fire management under current and future climatic conditions. We quantified forest fire activity in Mexico using georeferenced fire records for the period of 2005–2015 and examined its spatial and temporal relationships with a multiscalar drought index, the Standardized Precipitation-Evapotranspiration Index(SPEI). A total of 47975 fire counts were recorded in the 11-year long study period, with the peak in fire frequency occurring in 2011. We identified four fire clusters, i.e., regions where there is a high density of fire records in Mexico using the Getis-Ord G spatial statistic. Then, we examined fire frequency data in the clustered regions and assessed how fire activity related to the SPEI for the entire study period and also for the year 2011. Associations between the SPEI and fire frequency varied across Mexico and fire-SPEI relationships also varied across the months of major fire occurrence and related SPEI temporal scales. In particular, in the two fire clusters located in northern Mexico(Chihuahua, northern Baja California), drier conditions over the previous 5 months triggered fire occurrence. In contrast, we did not observe a significant relationship between drought severity and fire frequency in the central Mexico cluster, which exhibited the highest fire frequency. We also found moderate fire-drought associations in the cluster situated in the tropical southern Chiapas where agriculture activities are the main causes of forest fire occurrence. These results are useful for improving our understanding of the spatiotemporal patterns of fire occurrence as related to drought severity in megadiverse countries hosting many forest types as Mexico.

关键词： cluster drought forest fires geostatistics spatial clusters Standardised Precipitation-Evapotranspiration Index (SPEI)

I LOVE THIS GAME，I LOVE SHOES， I LOVE KICKS！

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中国服装（北京） 2007年第4X期 90-91页

作者： vega

陈圣，陈原野，他们的出现让北京八中男篮成为北京匡威杯初中联赛的三强之一。我们采访这对也许是北京初中联赛最好的一对双人搭档，是希望从北京匡威杯初中篮球联赛的参赛学生中，观察球鞋文化和篮球文化在青少年篮球爱好者人群里，是... 详细信息

陈圣，陈原野，他们的出现让北京八中男篮成为北京匡威杯初中联赛的三强之一。我们采访这对也许是北京初中联赛最好的一对双人搭档，是希望从北京匡威杯初中篮球联赛的参赛学生中，观察球鞋文化和篮球文化在青少年篮球爱好者人群里，是如何融合的。现在看来，因为篮球，喜欢篮球鞋，喜欢《鞋帮》是一个成立的推论。

关键词：篮球鞋鞋文化北京初中青少年鞋帮

Antimicrobial properties of sea anemone Anthopleura nigrescens from Pacific coast of Costa Rica

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Asian Pacific Journal of Tropical Biomedicine 2016年第5期6卷 418-421页

作者： Henry Borbn Sandra Vldes Javier Alvarado-Mesn Roy Soto Ilena vega Laboratory of Research and Development in Chemical Technology Department of ChemistryNational University Laboratory of Biochemistry and Biotechnology of Proteins Department of Biological ScienceNational University Laboratory of Natural Products and Biological Essays Department of ChemistryNational University

Objective: To evaluate the antimicrobial and antifungal activities of the aqueous and partitioned extract of sea anemone Anthopleura nigrescens(A. nigrescens).Methods: The sea anemone A. nigrescens was collected, minced, homogenized,lyophilized and then further partitioned with diethyl ether, acetone, ethanol and *** fractions were evaluated for antimicrobial activity against bacterial and fungal ***: Acetone extract was found to produce a pronounced inhibition of 7.0 mm against Proteus vulgaris and diethyl ether extract inhibited Pseudomonas aeruginosa with an inhibition zone of 6.5 mm. In antifungal activity, ethanol extract showed good activity against Botrytis cinerea, Trichoderma harzianum and Rhizopus oryzae compared with other strains. Acetone and ethanol extract of A. nigrescens showed activity against all of pathogens tested. Slight activity was observed in the water extract with inhibition zone of 1.5 ***: The present study revealed that sea anemone A. nigrescens may also contain some biologically active agents which have potential activity against pathogenic microorganisms.

关键词： Biological activity Antibacterial Antifungal Bioactive Sea anemone

Seven-year follow-up of posterior chamber phakic intraocular lens with central port design

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Eye and Vision 2021年第1期8卷 223-231页

作者： Luis Fernández-vega-Cueto Belén Alfonso-Bartolozzi Carlos Lisa David Madrid-Costa JoséF.Alfonso Fernández-vega Ophthalmological Institute Avda.Dres.Fernández-Vega 11433012 OviedoSpain Optometry and Vision Department Faculty of Optics and OptometryUniversity Complutense de MadridMadridSpain

Background:To assess the clinical outcomes of the Visian Implantable Collamer Lens(ICL)with a central port throughout 7 years of ***:Eighty-four eyes of 52 patients were evaluated over a follow-up period of 7 years after V4c ICL ***(UDVA)and corrected(CDVA)distance visual acuities,refraction,intraocular pressure(IOP),endothelial cell density(ECD)and vault were ***:The mean postoperative UDVA(logMAR)was 0.04±0.11,0.13±0.19 and 0.17±0.23 at 1-,5-and 7-years,respectively(P20 mmHg or an increase higher than 5 mmHg)occurred in any case throughout the 7-year of *** loss in ECD from the preoperative baseline at the last follow-up visit was 2.6%.No intraoperative or postoperative complications or adverse events occurred during the follow-up ***:The outcomes of this study show the long-term viability of the V4c ICL implantation as a surgical option for the correction of myopia.

关键词： Implantable Collamer Lens ICL Myopia Long-term

Study of the structural,ferroelectric,dielectric,and pyroelectric properties of the K0.5Na0.5NbO3 system doped with Li+,La3+,and Ti4+

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Journal of Advanced Ceramics 2020年第3期9卷 329-338页

作者： C.MONTERO-TAVERA M.D.DURRUTHY-RODRiGUEZ F.D.CORTES-vega J.M.YANEZ-LIMON Center for Research and Advanced Studies of IPN Campus QueretaroMexico National Evangelical University Paseo de los Periodistas#54Ensanche MirafloresSanto DomingoDistrito NacionalRepiblica Dominicana

Pure *** sNbO3(KNN)and KNN doped with Lit(6%mole),Lat(1.66%,5%,6%mole),and Ti+t(10%mole)were prepared by mixture of oxides using high-energy milling and conventional solid-state *** effects of the dopant on the physical properties of pure KNN have been evaluated based on the structural,ferroelectric,pyroelectric,and dielectric *** XRD measurements show that KNN pure sample contains a mixture of monoclinic and orthorhombic crystalline phases,with a slightly higher concentration of monoclinic *** contrast,all doped samples show a higher concentration of the orthorhombic phase,as well as the presence of a secondary phase(K6Nb10.8O3o),also detected by Raman *** samples with a higher concentration of this secondary phase,also present greater dielectric losses and lower values of remnant *** dielectric measurements allowed us to detect temperatures of structural transitions(orthorhombic-tetragonal,O-T)previous to the ferroelectric paraelectric transition(tetragonal-cubic,T-C),and also in this set of samples,a direct correlation was found between the values of remnant polarization and the corresponding pyroelectric signal response.

关键词： K0.5Na0.5NbO3(KNN) lead-free solid-state reaction structural properties pyroelectric properties dielectric properties Li,La,Ti doping elements