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Green Chemical Engineering 2022年第3期3卷 280-287页

作者： Felipe de la Cruz-Martinez Jose A.Castro-Osma Agustin lara-Sanchez Universidad de Castilla-la Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de Ciencias y Tecnologias QuimicasCiudad Real13071Spain Instituto de Investigaciones quimicas(IIQ) Departamento de Quimica Inorganica and Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Consejo Superior de Investigaciones Cientificas(CSIC)and University of SevillaSevilla41092Spain Universidad de Castilla-la Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de FarmaciaAlbacete02071Spain

Novel mono-and bimetallic scorpionate aluminum compounds have been designed and characterized by spec-troscopic *** organometallics complexes,in combination with tetrabutylammonium bromide as cocatalyst,displayed good catalytic activity for the cycloaddition of styrene oxide and CO_(2) under ambient *** the compounds tested,monometallic complex 3 featuring diethylamino groups showed the highest catalytic *** catalytic system catalyzed the formation of cyclic carbonate products from their corresponding epoxides at room temperature and 1 bar of CO_(2) pressure in the absence of a solvent in good yields and excellent selectivities.

关键词： CO_(2) Epoxides Cyclic carbonates Aluminum complexes

Sol–gel la2O3–ZrO2 mixed oxide catalysts for biodiesel production

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Journal of Energy Chemistry 2018年第2期27卷 565-572页

作者： Daniela Salinas Catherine Sepúlveda Néstor Escalona J.L.GFierro Gina Pecchi departamento de Fisicoquimica. facultad de ciencias quimicas Universidad de Concepcion Post Office 160-C Concepcion Chile departamento de Quimica Facultad de Ciencias Universidad del Biobio Post Office 5-C Concepcion Chile departamento Ingenieria Quimica y Bioprocesos Escuela de lngenieria Pontificia Universidad Catolica de Chile Avda. Vicuria Mackenna 4870 Maeul Santiago 7820436 Chile centro de Investigacion en Nanotecnolagia y Materiales Avanzados (CIEN-UC) Pontificia Universidad Catolica de Chile Post Office 306 Santiago Chile departamento de Quimica Fisica Facultad de Quimica Pontificia Universidad Catolica de Chile Post Offce 306 Santiago Chile Instituto de Catalisis y Petroleoquimica CSIC 28049 Madrid. Espana

Different la2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared la2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the la2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel *** biodiesel conversion（56% at 4 h） was obtained with the 3% la2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of la2O3. The decrease in the catalytic activity for 5% la2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% la2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.

关键词： la2O3 -ZrO2 Sol-gel Biodiesel Canola oil Transesterification

Effects of chlorpyrifos on enzymatic systems of Cydia pomonella （Lepidoptera： Tortricidae） adults

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Insect Science 2017年第3期24卷 455-466页

作者： laura Beatriz Parra Morales Raul Adolfo Alzogaray Liliana Cichon Silvina Garrido Jimena Soleno Cristina Monica Montagna laboratorio de Investigaciones Bioquimicas Quimicas y de Medio Ambiente Facultad de Ingenieria Universidad Nacional del ComahueBuenos Aires 1400 (Q83001BX) Neuquen facultad de ciencias del Ambiente y la Salud Universidad Nacional del Comahue Buenos Aires 1400 Neuquen centro de Investigaciones de Plagas e Insecticidas (CIPEIN-UNIdeFICONICET) Villa Martelli Buenos Aires Instituto de Investigacion e Ingenieria Ambiental (3iA-UNSAM) San Martin Provincia de Buenos Aires Instituto Nacional de Tecnologia Agropecuaria Estacion Experimental Alto Valle General Roca Argentina

The control program of codling moth （Cydia pomonella L.） in the Rio Negro and Neuqu6n Valley is intended to neonate larvae. However, adults may be subjected to sublethal pesticide concentrations generating stress which might enhance both mutation rates and activity of the detoxification system. This study assessed the exposure effects of chlorpyrifos on target enzyme and, both detoxifying and antioxidant systems of surviving adults from both a laboratory susceptible strain （LSS） and a field population （FP）. The results showed that the FP was as susceptible to chlorpyrifos as the LSS and, both exhibited a similar chlorpyrifos-inhibitory concentration 50 （IC50） of acetylcholinesterase （ACHE）. The FP displayed higher carboxylesterase （CarE） and 7-ethoxycoumarine O-deethylase （ECOD） activities than LSS. Both LSS and FP showed an increase on CarE activity after the exposure to low-chlorpyrifos concentrations, followed by enzyme inhibition at higher concentrations. There were no significant differences neither in the activities of glutathione S-transferases （GST）, catalase （CAT） and superoxide dismutase （SOD） nor in the reduced glutathione （GSH） content between LSS and FP. Moreover, these enzymes were unaffected by chlorpyrifos. In conclusion, control adults from the FP exhibited higher CarE and ECOD activities than control adults from the LSS. AChE and CarE activities were the most affected by chlorpyrifos. Control strategies used for C. pomonella, such as rotations of insecticides with different modes of action, will probably delay the evolution of insecticide resistance in FPs from the study area.

关键词： acetylcholinesterase antioxidant system chlorpyrifos codling moth detoxification enzymes

Extraterrestrial microspherules from Bajada del Diablo,Chubut,Argentina

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Geoscience Frontiers 2017年第1期8卷 137-149页

作者： M.J.Orgeira L.N.Castro G.A.Goldmann C.B.Prezzi E.Sileo D.R.Vega C.Franzosi R.D.Acevedo O.Martinez J.Rabassa J.F.Ponce O.R.Tofalo departamento de ciencias Geologicas-lGEBA Facultaci de Ciencias Exactas y NaturalesOniversidad de Buenos AiresCiudad UniversitariaPabelldn 11C1428EHABuenos AiresArgentina Consejo Nacional de lnvestigaciones Cientificas y Tecnicas de Argentina CONICEE Argentina departamento de lngenierfa Agrfcola y Uso de la Tierra Facultad de AgronomiaUniversidad de Buenos AiresAv.San Martin 4453CI417DSEBuenos AiresArgentina INQUIMAE Departamento de Qufmica Inorganica.Analitica y Quimica Fisica.Facultad de Ciencias Exactas y Naturales.Universidad de Buenos AiresPabellon IICiudad Universitaria.C1428EHABuenos Aires.Argentina Gerencia de lnvestigacion y Aplicaciones Comision Nacional de Energfa AtomicaUniversidad Nacional General San MartinBuenos AiresArgentina centro Austral de lnvestigaciones Cientificas CADIC-ConicetUshuaiaArgentina Universidad Nacional de la Patagonia"San Juan Bosco"Sede Esquel ChubutArgentina Universidad Nacional de la Patagonia"San Juan Bosco"Sede Ushuaia UshuaiaArgentina

The Quaternary infilling of a circular structure located in Bajada del Diablo,Chubut Province,Argentina has been proposed as a crater strewn field in previous *** we report the finding of about 65 microspherules collected in a trench excavated in the center of the *** majority of handpicked specimens are single,but some of them exhibit compound *** single specimens are spherical with a mean size of 137 nm,whereas the more complex samples show peduncles and drop *** crystal growth is recognized in the internal structure of some broken *** chemical composition from the surface and center of microspherules was determined by energy dispersive spectrometry employing *** EMPA and XRD analysis indicate that the microspherules are mainly composed of Fe and O with magnetite,Fe0with subordinate *** consideration of possible anthropogenic and volcanic origins,these spherulites are ascribed to an extraterrestrial *** accumulation rate of 47 microspherules per m2/yr is estimated for the studied *** value is two orders of magnitude higher than the reference flux for cosmic dust estimated for the last 1 Ma in the Transantarctic *** microspherules might have been generated as a byproduct of asteroid entry in the atmosphere.

关键词： Extraterrestrial microspherules Chemistry Bajada del Diablo Chubut Patagonia-Argentina

Chemical Evaluation of Groundwater from Supply Wells in the State of Coahuila,Mexico

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Journal of Water Resource and Protection 2014年第1期6卷 49-54页

作者： Hugo Saldarriaga-Norena Iliana de la Garza-Rodriguez Stefan Waliszewski Edith Colunga-Urbina Omar Amador-Munoz Mayela Moreno-Davila Rodrigo Morales-Cueto centro de Investigaciones quimicas Universidad Autonoma del Estado de MorelosCuernavacaMéxico facultad de ciencias quimicas Universidad Autónoma de CoahuilaSaltilloMexico Instituto de Medicina Forense Universidad VeracruzanaVeracruzMexico centro de ciencias de la Atmosfera Universidad Nacional Autonoma de MexicoCiudad de MexicoMexico

The present study is conducted with the purpose of determining the chemical characteristics of groundwater that supplies 16 wells in the state of Coahuila, which are used for different human activities. Sampling was conducted in January 2011. For 56% of the fifteen wells tested, analysis did not detect the presence of aluminum;however, wells 2, 3, 6, 8 and 13 had concentrations above the permissible limit established by the Mexican standard NOM-127-SSA1-1994. For cadmium, only the well 3 was above the Norm. Meanwhile, iron was above the permissible limit in eight wells (2, 4, 5, 6, 9, 12, 13 and 15). Lead exceeded the limit in wells 6, 7, 9, 10, 11 and 12. In general, for the rest of the parameters listed in the Norm, values were below allowable limits. By using Piper diagrams, it was observed that in general, the waters tested showed characteristic calcium bicarbonate. By establishing a matrix of correlations between chemical parameters, it was observed that the highest significant correlations occurred among carbonate hardness, calcium, lead and total alkalinity, with r2 values greater than 0.82. Also, high correlations were found between some metal species, suggesting a common origin. The allowed Principal Component Analysis and Cluster Analysis establish the associations between all analyzed physicochemical parameters, and they also determine the wells with similar characteristics.

关键词： Groundwater Coahuila Physicochemical Parameters Piper’s Diagram PCA

Optimization of Analytical Conditions to determine Steroids and Pharmaceuticals Drugs in Water Samples Using Solid Phase-Extraction and HPLC

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American Journal of Analytical Chemistry 2011年第8期2卷 863-870页

作者： Ramiro Vallejo-Rodriguez Alberto Lopez-Lopez Hugo Saldarriaga-Norena Mario Murillo-Tovar Leonel Hernandez-Mena centro de Investigacion y Asistencia en Tecnologia y Diseno del Estado de Jalisco(CIATEJ) Normalistas 800Colinas de la NormalGuadalajaraMexico facultad de ciencias quimicas Universidad Autonoma de CoahuilaRepublica Ote.SaltilloMexico

Two reliable methods were optimized to determine two steroids (17?-Estradiol and 17?-Ethinylestradiol) and two pharmaceutical drugs (ibuprofen and naproxen) using Solid-Phase Extraction (SPE) for sample preparation and High Performance Liquid Chromatography (HPLC) for analysis. SPE (C18) conditions were evaluated varying elution solvent volume, pH conditions and sample mass in the cartridge and reduction techniques of the extract. The efficiency of the analytical methods was evaluated by spiking ultrapure water samples with compounds at three and four levels of concentration for steroids and pharmaceutical drugs, re- spectively. The recoveries were independent (P > 0.05) of added mass of target analytes with a repeatability lower than 6.5% for steroids and 12.1% for pharmaceutical compounds. The recovery factor (coefficient of variation, CV) was higher than 83% for steroids (CV 93% for pharmaceuticals (CV degradation test using ozone, finding that the estimated limit of detection is sufficient to determine the residual mass (μg?L–1) of 17β-Estradiol after the experiment.

关键词： Steroids Pharmaceuticals Drugs Solid-Phase Extraction HPLC-DAD

Adsorption of NO on Activated Carbon： Equilibrium and Energetic Interactions

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材料科学与工程（中英文版） 2010年第4期4卷 41-46页

作者： Rosario Hernandez-Huesca Gelacio Aguilar-Armenta Gerardo Dominguez centro de lnvestigacion de la facultad de ciencias quimicas Benemerita Universidad Autonoma de Puebla Blvd. 14 sur y Av. San Claudio Ciudad Universitaria Puebla C.P. 72570 Pue. Mexico

We studied the capacity of activated carbon (C1) to adsorb NO at different temperatures using a glass, high-vacuum volumetric system to obtain information on the energy characteristics of the adsorption process. Adsorption equilibrium data were analysed by the Freundlich isotherm equation using regression analysis. We employed the Clausius–Clapeyron relationship to calculate the isosteric heats of NO adsorption using the equilibrium data of the isotherms measured at 273 and 293 K. The amount of NO adsorbed during reversible adsorption was higher than that adsorbed during total adsorption, probably due to semiquinones formation during total adsorption, which increased both the adsorption capacity of NO and adsorbate–adsorbent interactions during reversible adsorption.

关键词：活性炭吸附平衡数据相互作用能量特征可逆吸附高真空系统吸附过程回归分析