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Journal of Renewable Materials 2023年第11期11卷 3933-3943页

作者： Arnoldo E.Alfaro-Corres Daniel Gonzalez-Mendoza Esau Ruiz-Sanchez Carlos Ail-Catzin benjamin valdez-salas Federico Gutierrez-Miceli Arturo Reyes-Ramirez Jacques Fils Pierre Division of Postgraduate Studies and Research Tecnologico Nacional de MéxicoCampus ConkalConkalYucatán97345Mexico Institute of Agricultural Sciences Universidad Autonoma de Baja CaliforniaEjido Nuevo LeonMexicaliBaja California21705Mexico Instituto de Ingeniería Universidad Autónoma de Baja CaliforniaMexicaliBaja California21100Mexico Division of Postgraduate Studies and Research Tecnologico Nacional de MexicoCampus Tuxtla GutierrezTuxtla GutierrezChiapas29050Mexico

This work was carried out to evaluate the insecticidal effect of mono,bi and trimetallic nanoparticles(NPs)from leaf extract of habanero pepper(Capsicum chinense Jacq.)on the red flour beetle(Tribolium castaneum herbst.)and cotton mealybug(Phenacoccus solenopsis Tinsley).The results showed that Cu NPs,Cu/Mn NPs and Zn/Cu NPs had high insecticidal effect against T.castaneum(63%-80% mortality after 96 h).The Cu NPs and Zn/Cu NPs showed also insecticidal effect against P.solenopsis,but to a lesser extent(20%–28% after 96 h).With regards to the physicochemical characterization,Cu NPs had a zeta potential of 21.1 mV,whereas Cu/Mn NPs and Zn/Cu NPs exhibited zeta potentials of 200 mV.The polydispersity index(PDI)values for Cu NPs,Cu/Mn NPs,and Zn/Cu NPs were 10.1,29.16,and 14.34,respectively.The TF-IR spectra of the NPs varied from 600 to 4000 cm−1.The EDX weight percentages showed the presence of Cu(0.29%–2.4%),Mn(1.4%),and Zn(2.6%)in Cu/Mn NPs and Zn/Cu NPs,respectively.

关键词： Phytonanoparticles botanical insecticide pest control agronanotechnology

Green Synthesis of Silver Nanoparticles from Abronia villosa as an Alternative to Control of Pathogenic Microorganisms

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Journal of Renewable Materials 2020年第1期8卷 69-78页

作者： Ali Abdelmoteleb benjamin valdez-salas Ernesto Beltran-Partida Daniel Gonzalez-Mendoza Botany Department Faculty of AgricultureMenoufia UniversityShebin El-Kom32511Egypt Instituto de Ingeniería de la Universidad Autónoma de Baja California MexicaliBaja California21100México Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC) Ejido Nuevo LeónBaja California21705México

The aim of this study was to evaluate the antibacterial and antifungal activities of eco-friendly synthesized silver nanoparticles.The silver nanoparticles were synthesized by biological method using aqueous extract of Abronia villosa.Synthesis of silver nanoparticles was confirmed by color change and characterized using UV-visible spectroscopy,scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDX),dynamic light scattering(DLS),and zeta potential analysis.The SEM analysis revealed the presence of spherical silver nanoparticles of the size range 21 to 33 nm.Synthesized silver nanoparticles were used to evaluate their antibacterial effects at different concentrations(25,50,75 and 100μg/ml)on gram negative and gram positive bacteria.The biggest halo zone was observed at 75 and 100μg/ml concentrations of silver nanoparticles against both gram positive and gram negative bacteria.Antifungal activity of biosynthesized silver nanoparticles was evaluated against seven different phytopathogenic fungi.AgNPs showed high inhibition of radial growth toward all tested fungi.The highest inhibition of fungal growth by AgNPs was recorded against Macrophomina phaseolina(86.06±0.92%).Biosynthesized AgNPs using plant extract are a promising to use safety for various biomedical and agricultural applications.

关键词： Antibacterial activity antifungal activity green synthesis

Green Synthesis of Silver Nanoparticles Using Annona diversifolia Leaf Extract and Their Antimicrobial Application

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Journal of Renewable Materials 2020年第9期8卷 1129-1137页

作者： Rogelio Solorzano-Toala Daniel Gonzalez-Mendoza benjamin valdez-salas Vianey Mendez-Trujillo Federico Gutierrez-Miceli Ernesto Beltran-Partida Olivia Tzintzun-Camacho Tecnológico Nacional de México-Campus Tuxtla Gutiérrez Tuxtla Gutiérrez03940México Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California Mexicali21705México Instituto de Ingeniería de la Universidad Autónoma de Baja California Mexicali21100México Facultad de Medicina de la Universidad Autónoma de Baja California Mexicali21100México

The aim of this study was the synthesis of silver nanoparticle using Annona diversifolia Safford.The silver nanoparticles obtained were analyzed by spectroscopic methods and dynamic light scattering methods.The inhibition of AgNPs was evaluated against Bacillus cereus,Klebsiella pneumoniae and Enterobacter aerogenes.The results showed that AgNPs have high values at 3 keV and particle size between 45 to 58 nm with a homogenous morphology.The AgNPs showed growth inhibition against Klebsiella pneumoniae and Enterobacter aerogenes.Therefore studies are needed to confirm the potential antimicrobial of different AgNP from A.diversifolia in Gram negative and Gram positive bacteria.

关键词： Green chemistry AgNPs plants antimicrobial biotechnology

Anticorrosion behavior of conversion coatings obtained from unbuffered cerium salts solutions on AA6061-T6

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Journal of Rare Earths 2011年第10期29卷 961-968页

作者： KIYOTA Sayuri valdez benjamin STOYTCHEVA Margarita ZLATEV Roumen BASTIDAS Jose Maria Engineering Institute of UABC B.Juárez Blvd.and Normal St.21280 MexicaliB.C.Mexico CENIM-National Centre for Metallurgical Research CSIC8Gregorio del Amo Ave.28040 MadridSpain

The anticorrosive properties of cerium based conversion coatings deposited on AA6061-T6 alloy by immersion in tmbuffercd cerium chloride and cerium nitrate solutions in the presence of hydrogen peroxide were investigated and characterized by potentiodynamic po- larization （PDP） and electrochemical impedance spectroscopy （EIS） in 0.5 mol/L NaCl aqueous solution. The microstructure and chemical composition of the protective films were examined by scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDS）. It was found that the best corrosion protection was afforded by the samples treated during 600 s in cerium chloride solution at pH values ~5.5-4, showing higher amounts of cerium and polarization resistance values greater than 10 f~ m2. Moreover, an ennoblement of the corro- sion potential and decreasing of the cathodic and anodic currents were obtained compared with the cerium nitrate solutions application. This behavior was attributed to the influence of the deposition parameters such as type of the salt anion, i.e., chelating effect and chaotropic characteristics, pH fluctuations in the conversion solution and deposition time.

关键词： cerium based conversion coatings EIS PDP anticorrosion properties rare earths

Insecticidal Effect of Green Bimetallic Nanoparticles from Crotalaria longirostrata on Cotton Mealybug,Phenacoccus solenopsis

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Journal of Renewable Materials 2022年第10期10卷 2543-2552页

作者： Vianey Mendez-Trujillo Benjamín valdez-salas Mario Curiel-Alvarez Ernesto Beltran-Partida Arnoldo Alfaro-Corres EsaúRuiz-Sanchez Gerardo Bautista-Trujillo Olivia Tzintzun Camacho Onecimo Grimaldo-Juarez Carlos Ceceña-Duran Carlos Ail-Catzin Daniel González-Mendoza Facultad de Medicina de la Universidad Autónoma de Baja California Dr.Humberto Torres Sanginés S/NCentro CívicoMexicaliBaja CaliforniaMéxico Instituto de Ingeniería de la Universidad Autónoma de Baja California Calle de la Normal S/N y Boulevard Benito JuárezMexicaliBaja CaliforniaMéxico Instituto Tecnológico de Conkal División de Estudios de Posgrado e InvestigaciónAntigua Carretera Mérida-MotulConkalYucatánMéxico Facultad de Medicina Veterinaria y Zootecnia de la Universidad Autónoma de Chiapas ChiapasMéxico Universidad Autónoma de Baja California Instituto de Ciencias AgrícolasBaja CaliforniaMéxico

The present study was conducted to evaluate the impact of bimetallic nanoparticles(NPs)of copper(Cu)and zinc(Zn)from Crotalaria longirostrata on the insect mortality and cell viability of Phenacoccus solenopsis.The biosynthesis of bimetallic nanoparticles(Cu/Zn-NPs)from C.longirostrata was confirmed by the presence of a single peak around 378 nm.The hydrodynamic diameter of the Cu/Zn nanoparticles varied from 59 to 119 nm and their zeta potential was found to be−30.90 mV.The EDX analysis showed a strong signal for Cu and Zn(8 and 8.6 keV,respectively).The Cu/Zn-NPs showed an effective insecticide activity against P.solenopsis with 63%of insect mortality after 96 h treatment.However,further studies about nanotoxicity of Cu/Zn-NPs from C.longirostra are needed to reveal the exact mechanism of nanoparticles toxicity in insects.

关键词： Phytonanoparticles chipilin biocontrol agronanotechnology

Synthesis and Characterization of Green Potassium Nanoparticles from Sideroxylon Capiri and Evaluation of Their Potential Antimicrobial

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Journal of Renewable Materials 2021年第10期9卷 1699-1706页

作者： Judith Constantino-Alcazar Miguel Abud-Archila Benjamín valdez-salas Federico Gutierrez-Miceli Carlos Ceceña-Duran Blanca López-Valenzuela Daniel Gonzalez-Mendoza Tecnológico Nacional de México Instituto Tecnológico de Tuxtla GutiérrezTuxtlaGutiérrezC.P.03940México Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC) Ejido Nuevo LeónC.P.21705México Instituto de Ingeniería de la Universidad Autónoma de Baja California Mexicali21100México

In the present study,the green synthesis of potassium nanoparticles(K-NPs)was assessed using aqueous extract of Sideroxylon capiri.The potassium nanoparticles were analyzed by UV-visible spectroscopic techniques,X-ray spectrometers of energy dispersive(SEM-EDS)and dynamic light scattering.The results showed high values at 3.5 keV confirming the formation of potassium nanoparticles and the SEM analysis showed an agglomerated particles size between 360 to 200 nm with a spherical morphology.The K-NPs showed an effective antibacterial activity against the test organisms mainly with Bacillus cereus,Enterobacter aerogenes,Fusarium solani and Botrytis cinerea.However further studies about nanotoxicity of K-NPs are needed to confirm their potential in the control of the pathogen microorganisms under field conditions.

关键词： Antimicrobial effect green synthesis Sideroxylon capiri biocontrol

Green Synthesis of Bimetallic Nanoparticles From Prosopis juliflora(Sw)DC.,and Its Effect Against Cotton Mealybug,Phenacoccus solenopsis(Hemiptera:Pseudococcidae)

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 269-275页

作者： V.Mendez-Trujillo B.valdez-salas M.Carrillo-Beltran M.A.Curiel-Alvarez O.Tzintzun-Camacho C.Ceceña-Duran D.Gonzalez-Mendoza Facultad de Medicina de la Universidad Autónoma de Baja California Dr.Humberto Torres Sanginés S/NCentro Cívico21000MexicaliBaja CaliforniaMéxico Instituto de Ingeniería de la Universidad Autónoma de Baja California Calle de la Normal S/N y Boulevard Benito Juárez21100MexicaliBaja CaliforniaMéxico Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC).Carretera a Delta S/N C.P.21705 Ejido Nuevo LeónBaja CaliforniaMéxico

Phenacoccus solenopsis has been recognized as an aggressively invasive species on cotton plants in different countries.This study was conducted to investigate the effect of green synthesized Cu/Zn-nanoparticles using aqueous leaf extract of Prosopis juliflora(mezquite)against P.solenopsis.The scanning electron microscope(SEM)showed bimetallic nanoparticles of Cu/Zn-NPs with spherical shape with varying size of 74.33 nm to 59.46 nm.More than 30%mortality of P.solenopsis was observed with Cu/Zn-nanoparticles(100 ppm)at 96 hours after treatment.Negligible mortality of P.solenopsis was recorded with Cu/Zn solution(100 ppm)and aqueous P.juliflora extracts.The results of the viability test for Cu/Zn-nanoparticles of P.juliflora showed a significant reduction of the cell viability by 50%in insect exposed to Cu/Zn-nanoparticles-P.juliflora.Therefore studies about nanotoxicity of Cu/Zn-NPs of P.juliflora are needed to reveal the mechanism of toxicity this phytonanoparticles in P.solenopsis.

关键词： Photosynthesis biocontrol cotton mealybug nanoinsecticide

Behavioral parameters of six populations of/Wecavs phyllosomus longipennis(Heteroptera:Reduviidae)from areas with high and low prevalences of Trypanosoma cruzi human infection

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Insect Science 2021年第3期28卷 850-860页

作者： Jose Alejandro Martinez-lbarra benjamin Nogueda-Torres Oziel Dante Montanez-valdez J.Guadalupe Michel-Parra Miguel Angel Ambriz-Santos Laboratories de Entomologia Medica Centro Universitario del SurUniversidad de GuadalajaraCiudad GuzmanJaliscoMexico Cuerpo Academico de Cuencas Humedales y SustentabilidadDepartamento de Ciencias de la NaturalezaCentro Universitario del SurUniversidad de GuadalajaraCiudad GuzmanJaliscoMexico Becario de COFAA Escuela Nacional de Ciencias BioldgicasInstituto Politecnico NacionalCiudad de MexicoMexico

Three behaviors of epidemiological importance,namely feeding latency,feeding duration and defecation latency,for six populations of Meccus phyllosomus longipennis(Usinger)from areas of central,western and north-central Mexico with high(HP)and low(LP)prevalence of Trypanosoma cruzi(Chagas)human infection were evaluated in this study.The median feeding latency(the time taken to begin feeding)was highly variable between instars.Within-instar comparisons showed that at least 65%of the LP populations(N3 to adult)started to feed significantly(P<0.05)later than the HP population,with N1 showing no difference,and N2 from LP populations feeding sooner than those from HP populations.The six populations had similar median feeding durations within instars.A higher(P<0.05)percentage of the instars from HP populations defecated faster than the respective instars from the three LP populations.Approximately 25%of the young nymphs(N1 to N3)and females in the HP populations defecated<2 min postfeeding,compared with 4%-6%of the young nymphs and 1.3%-3%of females in the LP populations.Moreover,17.7%-38.8%of the older nymphs(N4 to N5)in the HP populations and 6.8%-13.4%in the LP populations defecated during or immediately after feeding.Our results indicate that the HP populations have a greater potential than the LP populations to transmit T.cruzi infections,which may underlie the differences in the prevalence of T.cruzi infection in some areas where M p.longipennis is currently distributed.

关键词： Chagas disease Meccus phyllosomus longipennis populations Mexico Tri-atominae Trypanosoma cruzi vectorial capacity

不同气候变化情景下亚洲北山羊（Capra sibirica）的响应（英文）

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Journal of Resources and Ecology 2020年第1期11卷 27-37页

作者： Eric Ariel L.salas Raul valdez Stefan MICHEL Kenneth G.BOYKIN 美国中央州立大学科学与工程学院美国俄亥俄州45384 新墨西哥州立大学鱼类、野生生物与保护生态系美国新墨西哥州88003 世界自然保护联盟物种生存委员会德国卡纳伍夫D-06578

目前很少见到关于气候变化影响亚洲北山羊物种栖息地的研究。通过调查气候变化对塔吉克斯坦东部亚洲北山羊(Capra sibirica)分布的影响,并采用生态位建模比较了亚洲北山羊的适宜栖息地的当前与未来分布情况。预计到2070年,现有适宜栖息... 详细信息

目前很少见到关于气候变化影响亚洲北山羊物种栖息地的研究。通过调查气候变化对塔吉克斯坦东部亚洲北山羊(Capra sibirica)分布的影响,并采用生态位建模比较了亚洲北山羊的适宜栖息地的当前与未来分布情况。预计到2070年,现有适宜栖息地的18%(2689 km^2)将变得不适宜亚洲北山羊的生存,损失的区域主要位于研究区域的东南部和西北部地区。新的适宜栖息地可能会扩展到当前亚洲北山羊范围之外:到2070年将扩展30%(4595 km^2)的范围,这些区域与亚洲北山羊现有的分布有很强的相关性。东南部的损失与该地区当前大多数的亚洲北山羊栖息地重叠,主要出现在比研究区域海拔低得多的区域(3500–4000 m)。当同时考虑损失和收益时,亚洲北山羊可能会净扩展到新的适宜栖息地。到2070年,亚洲北山羊的平均栖息地增加量约为30%(1379 km^2),表明适宜栖息地已向北部低温栖息地转移。研究结果有助于规划气候变化情景下塔吉克斯坦东部山区对生物多样性保护的潜在影响。应该特别注意东南地区的高地山羊种群,那里的栖息地可能由于气候对山区生态系统的影响而变得不适合该物种继续生存。

关键词：集成预测模型全球气候变化帕米尔山脉物种分布模拟山地有蹄类动物

Influence of Stainless Steel Weld Microstructure on Its Seawater Corrosion Performance

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材料科学与工程（中英文版） 2011年第1期5卷 65-70页

作者： Santilláin Néstor valdez benjamin Schorr Miguel Carrillo Mónica Martinez Alejandro Colton Samuel Universidad Autonoma de Baja California Instituto de Ingenieria Mexicali B.C. 21280 Mexico Universidad Autonoma de Baja California Facultad de Ciencias Ensenada B.C. 22800 Mexico Arizona Western College Main Campus Yuma AZ 85365 USA

Austenitic stainless steels (SS) (e. g., UNS S30403) are used for the fabrication of equipment and structures operating in marine environments. Frequently, their parts are joined by welding applying conventional techniques such as flux core arc welding (FCAW) and gas tungsten arc welding (GTAW). The aim of this investigation was to determine the influence of the microstructure of non-welded and welded S30403, including the heat-affected zone (HAZ), on their corrosion performance, when exposed to seawater in the laboratory. The experimental techniques involve electrochemical potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), electrochemical potentiokinetic reactivation (EPR) and surface characterization with a scanning electron microscope (SEM). Data obtained from the Bode and Nyquist diagrams correspond to a high resistance to charge transfer in the FCAW-weldzone and GTAW-HAZ zone. On the other hand, an unstable behaviour was reflected in the FCAW-HAZ zone and GTAW-weld zone at low frequency but an important corrosion process occurs at the FCAW-HAZ in a wide frequency range. These analyses were compared with the polarization results previously reported. The results of the EPR tests correspond to a small tendency to sensitization. The metallographic analysis depicts a high density of carbides precipitation on the FCAW-HAZ zone, while a significant decrease is observed in the GTAW-HAZ zone. In both cases the electron dispersive energy X-ray (EDX) analyses detects concentration of C, Cr and Fe. A complete setting of electrochemical results and its interpretation is presented.

关键词：不锈钢焊接海水腐蚀耐蚀性能药芯焊丝电弧焊焊接热影响区电化学阻抗谱扫描电子显微镜钨极氩弧焊