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Synthesis, Resolution and Absolute Configuration of 2,3-Dihydro-2-Tert-Butyl-3-N-Benzylquinazolin-4-One: A Possible Chiral Auxiliary for Synthesis of β-Amino Cyclohexancarboxylic Acid

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International Journal of Organic Chemistry 2014年第1期4卷 48-54页

作者： Fanny A. Cabrera-Rivera jaime Escalante Centro de Investigaciones Químicas Universidad Autónoma del Estado de Morelos Cuernavaca Mexico

3-Benzyl-2-(tert-butyl)-2,3-dihydroquinazolin-4(1H)-one rac-11 was resolved via the preparation of diastereomers with N-phthalyl-L-alanine chloride and its absolute configuration was determined by X-ray crystallographic analysis. This heterocycle has potential as a substrate chiral in asymmetric induction due to the steric effects of its tert-butyl group.

关键词： Chiral Auxiliary 2-Tert-Butyl-Quinazolin-4-One

Carbonaceous residues from biomass gasification as catalysts for biodiesel production

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Journal of Natural Gas Chemistry 2012年第3期21卷 246-250页

作者： Rafael Luque Antonio Pineda Juan C. Colmenares Juan M. Campelo Antonio A. Romero Juan Carlos Serrano-Ruiz Luisa F. Cabeza jaime Cot-Gores Departamento de Quimica Organica Universidad de Cardoba Campus de Rabanales Edif icio Marie Curie E-14014 Cardoba Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain

Tars and alkali ashes from biomass gasification processes currently constitute one of the major problems in biomass valorisation, generating clogging of filters and issues related with the purity of syngas production. To date, these waste residues find no useful applications and they are generally disposed upon generation in the gasification process. A detailed analysis of these residues pointed out the presence of high quantities of Ca （〉30 wt%）. TG experiments indicated that a treatment under air at moderate temperatures （400-800 ~C） decomposed the majority of carbon species, while XRD indicated the presence of a crystalline CaO phase. CaO enriched valorized materials turned out to be good heterogeneous catalysts for biodiesel production from vegetable oils, providing moderate to good activities （50%-70% after 12 h） to fatty acid methyl esters in the transesterification of sunflower oil with methanol.

关键词： biomass gasification residues biodiesel catalyst calcium oxide

ApoB-100, ApoE and CYP7A1 gene polymorphisms in Mexican patients with cholesterol gallstone disease

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World Journal of Gastroenterology 2010年第37期16卷 4685-4690页

作者： Sánchez-Cuén jaime Aguilar-Medina Maribel Arámbula-Meraz Eliakym Romero-Navarro José Granados Julio Sicairos-Medina Laura Ramos-Payán Rosalío División de Gastroenterología Hospital Regional ISSSTE Facultad de Ciencias Químico Biológicas Doctorado en Biotecnología y Maestría en Ciencias Biomédicas Universidad Autónoma de Sinaloa División de Inmunogenética Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán

AIM: To determine the possible association of the ApoB100 (Xba Ⅰ ), ApoE (Hha Ⅰ ) and CYP7A1 (Bsa Ⅰ ) gene polymorphisms, with the development of cholesterol gallstone disease (GD) in a Mexican population. METHODS: The polymorphisms were analyzed by polymerase chain reaction followed by restriction fragment length polymorphism, in two groups matched by ethnicity, age and sex: patients with GD (n = 101) and stone-free control subjects (n = 101). RESULTS: Allelic frequencies in patients and controls were: 34.16% vs 41.58% (P = 0.124) for X+of ApoB-100; 4.46% vs 5.94% (P = 0.501) for E2, 85.64% vs 78.22% (P = 0.052) for E3, 9.90% vs 15.84% (P = 0.075) for E4 of ApoE; and 25.74% vs 27.72% (P = 0.653) for C of CYP7A1. Differences in genotypic frequencies between the studied groups were not significant (P < 0.05). CONCLUSION: These results demonstrated that no association exists between the studied polymorphisms and cholelithiasis in this high prevalent population.

关键词： Apolipoprotein CYP7A1 Gallstones Mexicans Polymorphisms

Near-UV light assisted green reduction of graphene oxide films through l-ascorbic acid

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International Journal of Smart and Nano Materials 2021年第1期12卷 20-35页

作者： jaime Regis Sebastian Vargas Andrea Irigoyen Elsa Bramasco-Rivera Jose L.Bañuelos Luis C.Delfin Anabel Renteria Ulises Martinez Tommy RockwardYirong Lin Department of Mechanical Engineering The University of Texas at El PasoEl PasoTX USA W.M.Keck Center for 3D Innovation the University of Texas at El PasoEl PasoTX USA Department of Physics The University of Texas at El PasoEl PasoTX USA Materials Physics and Applications Los Alamos National LaboratoryLos AlamosNM USA Department of Mechanical Engineering The University of Texas At El Paso 500 W.University Ave.El Paso TX 79968United States

Recent studies have highlighted the effects of various stimuli on the chemical reduction of graphene oxide(GO)through green reductant L-ascorbic acid(L-AA);however,the combination of near ultraviolet(NUV)light to increase the reduction rate has yet to be thoroughly *** this study,drop-casted GO films were subjected to chemical reduction through L-AA with various levels of exposure under 405 nm NUV *** structure and uniformity of GO stackings that form the film were characterized through scanning electron microscopy(SEM)and wide-angle x-ray scattering(WAXS).Additionally,WAXS was used to track the removal of oxygen-containing functional groups along with Fourier-transform infrared(FT-IR)spectroscopy and x-ray photoelectron spectroscopy(XPS)as a function of L-AA and NUV light exposure *** results demonstrated that the interaction between L-AA and NUV exposure has a significant effect on the reduction of ***,the results that yielded the highest reduction(C-C bond concentration of 60.7%)were the longest L-AA and NUV light exposure times(48 hours and 3 hours,respectively).This report provides a study on the effects of NUV on the green reduction of GO films through L-AA with potential application in solar energy and chemical sensing applications.

关键词： Graphene Oxide Films Green Reduction Near Ultraviolet Light L-Ascorbic Acid Wide-Angle X-Ray Scattering

印度高止山脉西部山拉曼蛙的繁殖行为和炫耀鸣唱(英文)

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动物学报 2007年第3期53卷 575-578页

作者： Savitha N.KRISHNA jaime BOSCH Poornaprajna Institute of Scientific Research No.4 Sadashivanagar Bangalore India Museo Nacional de Ciencias Naturales CSICJosGutirrez Abascal 2 28006 MadridSpain

无尾两栖类炫耀鸣声的作用在于吸引雌性与占领领域。在印度高止山脉西部的森林中,作者在三个连续的繁殖季节(2003年5月-2005年10月)研究了在树洞中进行隐秘繁殖的山拉曼蛙(Ramanella montana)的繁殖行为和炫耀鸣唱。山拉曼蛙连续几年使... 详细信息

无尾两栖类炫耀鸣声的作用在于吸引雌性与占领领域。在印度高止山脉西部的森林中,作者在三个连续的繁殖季节(2003年5月-2005年10月)研究了在树洞中进行隐秘繁殖的山拉曼蛙(Ramanella montana)的繁殖行为和炫耀鸣唱。山拉曼蛙连续几年使用同样的树洞进行繁殖。在繁殖季节,雄蛙首先到达繁殖地点并进行炫耀鸣唱,其典型的鸣唱持续时间比较短,平均优势频率接近2160Hz。

关键词：山拉曼蛙繁殖行为声音高止山脉西部

Ethical Principles Underlying the Assessment of Indirect Losses Due to Earthquakes

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Open Journal of Civil Engineering 2021年第2期11卷 179-199页

作者： jaime García-Pérez Eric García-López Instituo de Ingeniería Ingeniería EstructuralEdif 2 Universidad Nacional Autónoma de México Ciudad Universitaria Coyoacán CDMX México National Institute of Criminal Sciences Magisterio Nacional 113 Tlalpan CDMX México

The reliability optimization process in earthquake engineering requires that the expected present value of the total cost is minimized, including the initial cost as well as the damage costs caused by earthquakes, which include indirect costs. One of these costs is concerned with how much society is willing to invest for preserving human life. Ethical principles, on which to base the assessment of this cost, are presented and discussed in this work. Individual and social values are analyzed. Finally, an optimal seismic design coefficient with the results obtained is calculated for a site with low seismicity.

关键词： Reliabilities Utility Indirect Losses Decision-Making Seismic Coefficients

Fractal Cracks Propagation in Aluminum

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Modeling and Numerical Simulation of Material Science 2013年第3期3卷 23-32页

作者： Francisco Casanova del Angel jaime Retama Velasco IINGEN Universidad Nacional Autónoma de México Mexico City Mexico SEPI ESIA Instituto Politécnico Nacional Mexico City Mexico

The theory of the fractal structure characterizing propagation of a crack through identification of its generator is presented. It’s generating fractal, the peculiarities of its construction and the way to measure its segments are defined, and a theorem on the inverse scale property of such and other of the axial symmetry property of the fractal generator are presented and demonstrated. The theory is applied on 6061-T6 aluminum samples, using SENB probes. Direction of crack propagation and its fractal dimension are calculated numerically. Results obtained from modeling the direction of crack propagation through mechanics of elastic linear fracture and the one proposed here, called geometrical fractal fracture, are compared, thus developing the mirror case.

关键词： Geometrical Fractal Fracture Crack Propagation Aluminum Stress Intensity Factor Fractal Dimension

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Foreword

Foreword

第三届风险分析与危机反应国际学术研讨会

作者： jaime Ortiz Steve Sears

＜正＞This volume collects the papers presented at the 3rd International Conference on Risk Analysis and Crisis Response （RACR-2011） held at Texas A＆M International University in Laredo, Texas on May 22–25, 2011. ...

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机器人学家要给人类添加第三只手臂

科技纵览 2023年第3期 22-27,46,2页

作者： Dario Farina Etienne Burdet Carsten Mehring jaime Ibanez Chris Philpot(图) 不详

如果多了一条肢体,你能做什么? 想象一位外科医生正在进行一台精细手术,这需要她的专业技能以及稳定的手:她的两只手用于操作手术器械,而附在她身上的第三只机械手则扮演着支持角色.或者想象一位建筑工人,非常感激他额外的机械手支撑住... 详细信息

如果多了一条肢体,你能做什么? 想象一位外科医生正在进行一台精细手术,这需要她的专业技能以及稳定的手:她的两只手用于操作手术器械,而附在她身上的第三只机械手则扮演着支持角色.或者想象一位建筑工人,非常感激他额外的机械手支撑住了沉重的梁,方便他用自己的两只手把梁固定好.

关键词：机械手机器人建筑工人手术器械外科医生专业技能手臂角色