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Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana V.Kharissova Lucy T.gonzález Yolanda Peña Méndez Igor e.Uflyand Idalia gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials chemistry.In particular,carbon allotropes are widely used in these composites being widely applied for medical purposes.Observing a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and nanocarbons.These composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,etc.These composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among others.Combination of various synthesis techniques can be also carried out for composite preparation.Natural or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from biomass.Resulting biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic polymers.In these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial effect.gO→g reduction and higher HA decoration were observed in several experiments.The morphology of p

关键词： Hydroxyapatite Carbon nanotubes graphene Quantum dots Fullerenes Nanodiamonds

PtRu nanoparticles supported on noble carbons for ethanol electrooxidation

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Journal of energy Chemistry 2022年第3期31卷 168-180,I0006页

作者： Alberto Rodríguez-gómez enrico Lepre Luz Sánchez-Silva Nieves López-Salas Ana Raquel de la Osa Faculty of Chemical Sciences and Technologies University of Castilla-La ManchaEnrique Costa Novella Building.Avda.Camilo Jose Cela1213071 Ciudad RealSpain Colloid Chemistry department Max Planck Institute of Colloids and InterfacesAm Mühlenberg 114476 PotsdamGermany

In this work,three cytosine derived nitrogen doped carbonaceous materials(noble carbons,NCs)with different atomic C/N ratios and porous networks have been synthesized and used as supports for Pt Ru electrocatalysts in the ethanol oxidation reaction(eOR)for clean hydrogen production.Both,the metal phase and the carbon support play critical roles in the electrocatalysts final performance.Lower NPs size distribution was obtained over supports with low atomic C/N ratios(i.e.,4 and 6)and defined porosity(i.e.,1701 m^(2)g^(-1)for Pt Ru/CNZ and 1834 m^(2)g^(-1)for Pt Ru/CLZ,respectively).In contrast,a lower C/N ratio and poor porous network(i.e.,65 m^(2)g^(-1),Pt Ru/CLK)led to the largest particle size and fostered an increase of the alloying degree between Pt and Ru NPs(i.e.,3%for C/N~6 and 28%for C/N~3).electrochemical active surface area was found to increase with decreasing NPs size and the alloy extent,due to a higher availability of Pt active sites.Accelerated degradation tests showed that Pt Ru/NCs outperform similar to Pt Ru NPs on commercial carbon pointing at the stabilizing effect of NCs.Pt Ru/CNZ exhibited the best electrochemical performance(i.e.,69.1 m A mgPt-1),outperforming Pt Ru/CLZ and Pt Ru/CLK by3-and 9-fold,respectively,due to a suitable compromise between particle sizes,degree of alloy,textural properties and elemental composition.Best anodes were scaled-up to a proton exchange membrane cell and Pt Ru/CNZ was proved to provide the best electrocatalytic activity(262 m A cm^(-2)and low energy requirements),matching the values obtained by the state of the art of eOR electrocatalysts.

关键词： Noble carbon Cytosine H2 production ethanol electrooxidation PtRu anode PeM cell

evaluating the influence of air pollution on solar radiation observations over the coastal region of Alicante(Southeastern Spain)

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Journal of environmental Sciences 2023年第4期126卷 633-643页

作者： Igor gómez Sergio Molina Juan Joségaliana-Merino department of Applied Physics Faculty of SciencesUniversity of AlicanteSection 99E-03080 AlicanteSpain Multidisciplinary Institute for environmental Studies(MIeS)“Ramón Margalef” University of AlicanteSection 99E-03690 AlicanteSpain department of Physics Systems Engineering and Signal TheoryUniversity of AlicanteSection 99E-03080 AlicanteSpain University Institute of Physics Applied to Sciences and Technologies University of AlicanteSection 99E-03080 AlicanteSpain

The present study evaluates ground-based downward surface shortwave radiation (Rs) over the coastal region of Alicante (Southeastern Spain).Hourly measurements collected over the eleven-year period 2010-2020 are used.Two weather stations located over the region capital,Alicante,have been selected as representative of urban and suburban typologies.Two additional weather stations far from the city have been selected representing rural typologies.Rs is significantly reduced over the urban station during the morning hours within the winter season compared to the observations recorded over the suburban and rural stations,with a global mean difference of-81 and-120 W/m^(2)at 10 LT,respectively.However,no significant differences are obtained during the midday sun,with a global mean difference of-20 W/m^(2)between the urban and rural stations.With the aim of explaining these differences,the current paper investigates the relationship between Rsand different air pollutants:NOx,SO_(2),and fine particulate matter (PM_(2.5)and PM_(10)) as well as the wind field measured at the urban and suburban stations.The results found in this work point towards a close relationship between Rsand NOxconcentrations annual cycles,which are also influenced by the prevailing wind circulations observed over the study area.A global mean NOxconcentration of 107μg/m^(3)is observed over the urban station at 10 LT during the winter season.In contrast,these high concentrations are significantly reduced over the suburban station,with global mean value of 40μg/m^(3)at 10 LT,for this period of the year.

关键词： Solar radiation Air pollution Weather-concentration relationship Coastal cities Atmospheric conditions Wind field

Caerulin-induced pancreatitis in rats: Histological and genetic expression changes from acute phase to recuperation

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World Journal of gastroenterology 2006年第25期12卷 3999-4003页

作者： Javier Magaa-gómez guillermo López-Cervantes Ana María Calderón de la Barca departamento de Nutrición Centro de Investigación en Alimentación y desarrollo A.C. HermosilloSonoraMéxicoDepartamento de Patología Hospital Infantil del Estado de SonoraHermosilloSonoraMéxicoDepartamento de Nutrición Centro de Investigación en Alimentación y DesarrolloA.C.HermosilloSonoraMéxico

瞄准：为了学习组织学、联系胰腺炎的蛋白质 mRNA 累积，在老鼠从导致 caerulin 的胰腺炎的尖锐阶段胰改变到恢复。方法：尖锐胰腺炎被 caerulein 在男 Wistar 老鼠导致并且列在后面在上面为 90 d 由组织学并且胰的 mRNA 分析。胰在 0 ... 详细信息

瞄准：为了学习组织学、联系胰腺炎的蛋白质 mRNA 累积，在老鼠从导致 caerulin 的胰腺炎的尖锐阶段胰改变到恢复。方法：尖锐胰腺炎被 caerulein 在男 Wistar 老鼠导致并且列在后面在上面为 90 d 由组织学并且胰的 mRNA 分析。胰在 0 点被把， 9， 24 h 并且 3， 5， 15， 30， 60， 90 d 正式就职以后。浮肿(e) ， polymorphonuclear neutrophil (PMN ) 渗入，细胞质的空泡形成(V) ，酶原小粒弄空(ZD ) 和腺泡组织的破坏(广告) 是评估的用显微镜。联系胰腺炎的蛋白质(奶头) 和 L13A mRNAs 的累积被即时 PCR 确定。结果：主要组织学的变化出现在为 PMN 渗入和细胞质的 V 正式就职以后的 9 h 在为 e 和 ZD 的 24 h 和 3 d 分别地。所有参数在 5 d 以后被恢复，除了推迟了超过 30 d 的 ZD。主要广告在 15 d 以后被观察，值在 30 d 以后回到了正常。同样到组织学的变化， PAP mRNA 的累积在 24 h 与最高的累积在 9 h 被增加，差别消失在 5 d 以后。结论：从尖锐阶段发生到胰的胰腺炎，新生和重新区别的恢复并且奶头表示是只胰腺炎的尖锐回答。

关键词：雨蛙肽胰腺炎组织遗传疾病

Mechanical properties of the A356 aluminum alloy modified with la/Ce

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Journal of Rare earths 2013年第8期31卷 811-816页

作者： e. Aguirre-de la Torre R. Pérez-Bustamante J. Camarillo-Cisneros C.D. gómez-esparza H.M. Medrano-Prieto R. Martínez-Sánchez Advanced Materials Research Center (CIMAV) National Laboratory of Nanotechnology

The research of rare earths for the synthesis of materials with improved mechanical performance is of great interest when they are considered for potential applications in the automotive industry. In this regard, the effect on the mechanical properties and microstmcture of the automotive A356 aluminum alloy reinforced with 0.2 （wt.%） AI-6Ce-3la （ACL） was investigated. The ACL was added to the melted A356 alloy in the as-received condition and processed by mechanical milling. In the second route, the effect of the ACL processed by mechanical milling and powder metallurgy techniques was investigated, and compared with the results ob- tained from the A356 alloy strengthened with ACL in the as-received condition. Microstmctural properties were evaluated by means of X-ray diffraction in order to observe the solubility of Ce/la in the A1 matrix. In addition, electron microscopy was employed in or- der to investigate the effect of milling time on the size and morphology of la/Ce phase under milling process. Mechanical properties of the A356 alloy modified with ACL were measured by hardness and tensile test. For comparison unmodified specimens of the A356 were characterized according to the previous procedure. The microstructural and mechanical characterization was carried out in specimens alter solution and artificial aging. Observations in scanning electron microscopy indicated a homogeneous dispersion of la/Ce phases by using both routes; however, mechanical results, in the modified A356 alloy with the ACL in the as-received condi- tion, showed an improvement in the mechanical performance of the A356 alloy over that reinforced with the ACL mechanically milled.

关键词： A356 rare earths mechanical milling mechanical properties

Mapping forest vegetation patterns in an Atlantic-Mediterranean transitional area by integration of ordination and geostatistical techniques

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Journal of Plant ecology 2018年第1期11卷 114-122页

作者： Adriana e.Olthoff Cristina gómez Josu g.Alday Carolina Martínez-Ruiz ecology Area Agroforestry Sciences DepartmentE.T.S.II.AA.University of ValladolidAvda.Madrid 5034071 PalenciaSpain department of geography and environment School of GeoscienceUniversity of AberdeenAberdeen AB243UEUK department of Forest Systems and Resources CIFOR-INIACtra.de La Coruña km 7.528040 MadridSpain department of Crop and Forest Sciences-AgROTeCNIO Center University of Lleida25198 LleidaSpain Sustainable Forest Management Research Institute University of Valladolid-INIAE.T.S.II.AA.Avda.Madrid 5034071 PalenciaSpain

Aims Forest vegetation variability may be explained by the complex inter-play among several spatial structuring factors,including climate and topography.We modelled the spatial variability of forest vegetation assemblages and significant environmental variables along a com-plex environmental gradient or coenocline to produce a detailed cartographic database portraying the distribution of forests along it.Methods We combined an analysis of ordination coenoclines with kriging over 772 field data plots from the third Spanish National Forest Inventory in an Atlantic-Mediterranean transitional area(northern Spain).Important Findings The best fitted empirical semivariogram revealed a strong spatial structure of forest species composition along the complex envi-ronmental gradient considered(the climatic-topographic gradient from north to south).The steady and gradual increase of semivari-ance with a marked lag distance indicates a gradual turnover of forest assemblages according to the climatic-topographic vari-ations(regional or local).Two changes in the slope of the semi-variogram suggest the existence of two different scales of spatial variation.The interpolation map by Kriging of forest vegetation assemblages along the main coenocline shows a clear spatial dis-tribution pattern of trees and shrubs in accordance with the spa-tial variation of significant environmental variables.We concluded that the multivariate geostatistical approach is a suitable technique for spatial analysis of forest systems employing data from national forest inventories based on a regular network of field plots.The development of an assortment of maps describing changes in veg-etation assemblages and variation in environmental variables is expected to be a suitable tool for an integrated forest management and planning.

关键词： coenocline Kriging National Forest Inventory ordination variogram

Omics analyses in citrus reveal a possible role of RNA translation pathways and Unfolded Protein Response regulators in the tolerance to combined drought, high irradiance, and heat stress

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Horticulture Research 2023年第7期10卷 165-175页

作者： Damián Balfagón Sara IZandalinas Tadeu dos Reis de Oliveira Claudete Santa-Catarina Aurelio gómez-Cadenas departamento de Biología Bioquímica y Ciencias NaturalesAv.Sos Baynat s/n.Universitat Jaume I46520 Castellóde la PlanaSpain laboratório de Biologia Celular e Tecidual(LBCT) Centro de Biociências E Biotecnologia(CBB)Universidade Estadual Do Norte Fluminense Darcy Ribeiro(UENF)Av.Alberto Lamego 2000Campos Dos GoytacazesRJ28013-602Brazil

environmental changes derived from global warming and human activities increase the intensity and frequency of stressful conditions for plants.Multiple abiotic factors acting simultaneously enhance stress pressure and drastically reduce plant growth,yield,and survival.Stress combination causes a specific stress situation that induces a particular plant response different to the sum of responses to the individual stresses.Here,by comparing transcriptomic and proteomic profiles to different abiotic stress combinations in two citrus genotypes,Carrizo citrange(Citrus sinensis×Poncirus trifoliata)and Cleopatra mandarin(Citrus reshni),with contrasting tolerance to different abiotic stresses,we revealed key responses to the triple combination of heat stress,high irradiance and drought.The specific transcriptomic response to this stress combination in Carrizo was directed to regulate RNA metabolic pathways and translation processes,potentially conferring an advantage with respect to Cleopatra.In addition,we found endoplasmic reticulum stress response as common to all individual and combined stress conditions in both genotypes and identified the accumulation of specific groups of heat shock proteins(HSPs),such as small HSPs and HSP70s,and regulators of the unfolded protein response,BiP2 and PDIL2-2,as possible factors involved in citrus tolerance to triple stress combination.Taken together,our findings provide new insights into the acclimation process of citrus plants to multiple stress combination,necessary for increasing crop tolerance to the changing climatic conditions.

关键词： citrus Citrus stress

Plant micro-reserves in Valencia(e. Spain):A model to preserve threatened flora in China?

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Plant Diversity 2017年第6期39卷 383-389页

作者： Simón Fos emilio laguna Juan Jimenez Miguel Angel gómez-Serrano VAeRSA-generalitat Valenciana Avda. Corts Valencianes Servicio de Vida Silvestre Generalitat Valenciana C./ Castan Tobenas Centro para la experimentación e Investigación Forestal (CIeF) Generalitat Valenciana Avda. Comarques del País Valencia

The Valencian Community(eastern Spain) was the pioneer territory establishing plant micro-reserves(PMRs). Its model to protect small sites for endemic and endangered plants has been exported to several countries around the globe. This paper highlights 1) the role of PMRs to complement the protection provided by large protected areas, 2) how the establishment of PMRs fosters the increase of floristic knowledge, and 3)the fact that continuous monitoring of PMRs also yields new records of endangered species found within the same PMRs. The flexibility of the PMR approach-it can be adapted to other national and regional legislationsallows its transfer to other rich-biodiversity regions and countries such as China.

关键词： Plant micro-reserves in situ conservation Threatened species endemic plants Protected areas

Airborne bacteria associated with particulate matter from a highly urbanised metropolis:A potential risk to the population’s health

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Frontiers of environmental Science & engineering 2022年第9期16卷 99-114页

作者： María del Carmen Calderón-ezquerro elizabeth Selene gómez-Acata Carolina Brunner-Mendoza Instituto de Ciencias de la Atmósfera y Cambio Climático Universidad Nacional Autónoma de MéxicoCiudad de México 04510Mexico Facultad de Medicina Universidad Nacional Autónoma de MéxicoCiudad de México 04510Mexico

Bacteria in the air present patterns in space and time produced by different sources and environmental factors.Few studies have focused on the link between airborne pathogenic bacteria in densely populated cities,and the risk to the population’s health.Bacteria associated with particulate matter(PM)were monitored from the air of Mexico City(Mexico).We employed a metagenomic approach to characterise bacteria using the 16S rRNA gene.Airborne bacteria sampling was carried out in the north,centre,and south of Mexico City,with different urbanisation rates,during 2017.Bacteria added to the particles were sampled using high-volume PM_(10) samplers.To ascertain significant differences in bacterial diversity between zones and seasons,the Kruskal-Wallis,Wilcoxon tests were done on alpha diversity parameters.Sixty-three air samples were collected,and DNA was sequenced using next-generation sequencing.The results indicated that the bacterial phyla in the north and south of the city were Firmicutes,Cyanobacteria,Proteobacteria,and Actinobacteria,while in the central zone there were more Actinobacteria.There were no differences in the alpha diversity indices between the sampled areas.According to the OTUs,the richness of bacteria was higher in the central zone.Alpha diversity was higher in the rainy season than in the dry season;the Shannon index and the OTUs observed were higher in the central zone in the dry season.Pathogenic bacteria such as Kocuria,Paracoccus,and Micrococcus predominated in both seasonal times,while Staphylococcus,Corynebacterium,and Nocardioides were found during the rainy season,with a presence in the central zone.

关键词： Airborne bacteria Urbanisation PM10 Mexico City Microbiome