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Oxidation and Coatings for Power Generation： New Super Ultra Critical Steam Turbines

中国腐蚀与防护学报 2009年第4期29卷 318-319页

作者： F. j. perez Grupo de Investigacion de Ingenieria de Superficies y Materiales Nanoestructurados U. C. M. N°910627 Facultad de Ciencias Quimicas Universidad Complutense de Madrid. 28040 Madrid Spain

The steels with chromium contents between 9%and 12%wt are used for power plants with advanced steam oxidation *** present good creep properties as 9%Cr steels and good oxidation resistance,at the temperatures range between 500℃～600℃.In the last years numerous investigation in development of coatings has been realized with the aim the protected them against the oxidation in order to allow operation of steam turbines at 650℃.In this study,Al-Hf protective coatings were deposited by CVD-FBR on ferritic steel HCM-12A followed by a diffusion heat treatment,have shown to be protective at 650℃under steam for at least 3000 hours of laboratory steam exposure under atmospheric *** and composition of coatings were characterized by different techniques, such as scanning electron microscopy(SEM),electron probe microanalysis,and X-ray diffraction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermogravimetric measurements (TG) during the initial stages oxidation of the P92 ferritic steel without and of Al and Al/Si coating by chemical vapour deposition in fluidized bed reactors(CVD-FBR) at 650℃in Ar+20%H_2O for 150 h were *** order to go forward to coatings design the Thermocalc code is used as base for the MSdata. TG-MS experiments were conducted in a closed steam loop in order to obtain information about the oxyhydroxides formation as reaction between coatings and *** those results the role of the different coating element could be established and optimized for the coating *** oxidation mechanism based on the TG-MS results is *** morphology/composition and structure of the oxidized samples were also studied using SEM/EDS and XRD techniques.

关键词：氧化金属腐蚀防护

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Water Striders:The Biomechanics of Water Locomotion and Functional Morphology of the Hydrophobic Surface(Insecta:Hemiptera-Heteroptera)

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j.urnal of Bionic Engineering 2008年第2期5卷 121-126页

作者： P. j. perez Goodwynj.j.n-tong Wang Zhou-j. Wang Ai-hong j. Zhen-dong Dai K. Fuj.saki Institute for Bio-lnspired Structure and Surface Engineering （IBSS） Nanjing University of Aeronautics andAstronautics Nanjing 210019 P. R. China Laboratory oflnsect Ecology Graduate School of.4griculture Kyoto University Kyoto 606-8502 Japan

Water striders are insects living on the water surface, over which they can move very quickly and rarely get wetted. We measured the force of free walking in water striders, using a hair attached to their backs and a 3D strain gauge. The error was calculated by comparing force and data derived from geometry and was estimated as 13%. Females on average were stronger （1.32 mN） than males （0.87 mN）, however, the ratio of force to weight was not significantly different. Compared with other lighter species, Aquarius paludum seems stronger, but the ratio of force to weight is actually lower. A. paludum applies about 0.3 ***^-1 to 0.4 *** 1 with its mid-legs, thus avoiding penetrating the surface tension layer while propelling itself rapidly over the water surface. We also investigated the external morphology with SEM. The body is covered by effectively two layers of macro-and micro-hairs, which renders them hydrophobic. The setae are long （40 μm-60μm） and stiff, being responsible for waterproofing, and the microtrichia are much smaller （〈10μm）, slender, and flexible, holding a bubble over the body when submerged.

关键词： force surface tension aquatic insect morphology microtrichia setae

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Quantitative Assessment of Different Phenolic Compounds in Texas Olive Oils versus Foreign Oils

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j.urnal of Agricultural Science and Technology 2010年第5期4卷 61-67页

作者： N. S. A. Malik j. L. perez United States Department of Agriculture Agricultural Research Service 2413 E. Hwy83 Weslaco TX 78596 USA

The purpose of this study was to evaluate the quality of the first time commercially produced Texas olive oil. Thus, quantitative assessments of different phenolic compounds in Texas olive versus foreign oils were performed using modern analytical techniques. Samples of commercial and laboratory extracted Texas olive oils were compared with sample from 11 foreign oils. Total polyphenols in each oil sample were measured by the Folin-Ciocalteau method. Individual polyphenols were separated by high performance liquid chromatography and identified by comparing retention time and UV spectra with known compounds. Free acidity and the UV absorption were measured by standard AOCS （American Oil Chemists Society） methods. The Texas olive oil contained 27% higher amounts of total phenols than the highest amount of a foreign oil sample. Similarly, Texas olive oil also contained higher amounts ofoleuropein, hydroxytyrosol, and pinoresinol compared to all other oils tested. Thus, olive oil pressed from olives harvested in hot summer days will be very competitive with other oils with regard to polyphenols contents and hence its health benefits. The free acidity in the commercial Texas oil was 0.35%, based on oleic acid, and its coefficient at K268 UV absorption was 〈0.166. These numbers affirm that the Texas olive is ＂Extra Virgin＂.

关键词： Oleuropein olive oil pinoresinol polyphenols tyrosol.

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Malignant cardiac metastasis from breast cancer: Imaging contribution to surgical attitude

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Case Reports in Clinical Medicine 2013年第8期2卷 450-453页

作者： Victor j. Ovej.ro-Gomez L. Martin-Cuesta V. Alij. j. Villalba j. Rodríguez-Cabello j. perez j. M. Baj.-Arenas Department of Cardiology Hospital Sierrallana de Torrelavega Torrelavega Spain Department of Gynaecology Hospital Sierrallana de Torrelavega Torrelavega Spain Department of Medical Oncology Hospital Sierrallana de Torrelavega Torrelavega Spain Department of Radiology Hospital Sierrallana de Torrelavega Torrelavega Spain Department of Surgery Hospital Sierrallana de Torrelavega Torrelavega Spain

Metastasic cardiac disease from the breast is rarely diagnosed in the lifetime. It has a poor prognosis and limited management. Both echocardiography and computerized tomography (CT) should be the first imaging studies in suspicion of this entity. Other diagnostic methods should be based on the possibilities of treatment although a histopathological analysis of the metastasic mass is needed to confirm the diagnosis. Magnetic resonance imaging (MRI) could be useful to complete a morphological and functional evaluation in case of surgical removal.

关键词： Cancer Breast Metastasis Cardiac Imaging

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Cryopreservation of Cat’s Claw (<i>Uncaria tomentosa</i>)

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American j.urnal of Plant Sciences 2015年第18期6卷 2960-2972页

作者： j. perez A. Guillen K. Ramos F. Engelmann A. Abdelnour-Esquivel Escuela de Biología Instituto Tecnológico de Costa Rica Cartago Costa Rica IRD UMR DIADE Montpellier France Centro de Investigación en Biotecnología Instituto Tecnológico de Costa Rica (ITCR) Cartago Costa Rica

Uncaria tomentosa presents tomentum that resembles cat’s claws, hence its common name, is a plant that produces various secondary metabolites that are traditionally used in alternative medicine. The natural distribution of this species has been affected by indiscriminate harvesting from its habitat. In the present research, cryopreservation (liquid nitrogen, LN, -196°C) was evaluated as an option for ex situ conservation of this species. The following techniques were evaluated: vitrification and encapsulation-dehydration of apices, vitrification of cell suspensions, and seed desiccation and vitrification. Preculture conditions and exposure times to LS and PVS2 were evaluated. Apex survival was the highest (82%) with preculture in 0.25 M sucrose followed by incubation for 20 and 30 min in LS and PVS2, respectively, prior to cooling in LN. The encapsulation-dehydration technique was evaluated by using sucrose preculture and different capsule moisture contents. Survival of apices cooled in LN was not significantly different between treatments and varied from 31.8% to 52.9% for capsule moisture contents between 22.7% and 20.3%. For cell suspensions precultured in 0.5 M sucrose, cell multiplication and formation of calli with very good appearance were observed in 61.1% of the cultures following vitrification. For cryopreservation of seeds, germination was 89.5% using the desiccation technique and 67.6% to78.1% using vitrification.

关键词： Uncaria tomentosa Vitrification Encapsulation-Dehydration Conservation of Plant Genetic Resources PVS2 Preculture Regeneration Media

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LP-SVR Model Selection Using an Inexact Globalized Quasi-Newton Strategy

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j.urnal of Intelligent Learning Systems and Applications 2013年第1期5卷 19-28页

作者： Pablo Rivas-Perea j.an Cota-Ruiz j. A. perez Venzor David Garcia Chaparro j.se-Gerardo Rosiles Department of Computer Science Baylor University Waco TX USA Department of Electrical and Computer Engineering Auto- nomous University of Ciudad Juarez Ciudad Juárez Mexico Science Applications International Corporation El Paso TX USA.

In this paper we study the problem of model selection for a linear programming-based support vector machine for regression. We propose generalized method that is based on a quasi-Newton method that uses a globalization strategy and an inexact computation of first order information. We explore the case of two-class, multi-class, and regression problems. Simulation results among standard datasets suggest that the algorithm achieves insignificant variability when measuring residual statistical properties.

关键词： Hyper-Parameter Estimation Support Vector Regression Machine Learning Data Mining

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Chemical Degradation of Indigo Potassium Tetrasulfonate Dye by Advanced Oxidation Processes

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j.urnal of Environmental Protection 2014年第13期5卷 1342-1351页

作者： Veronica Camargo Elba Ortiz Hugo Solis Carlos M. Cortes-Romero Sandra Loera-Serna Carlos j. perez Department of Basic Sciences Universidad Autónoma Metropolitana Azcapotzalco Mexico City Mexico Division of Industrial and Systems Engineering Universidad Politecnica del Valle de México Estado de Mexico Mexico

The experimental degradation of a water soluble dye, potassium indigo tetrasulfonate salt, has been studied using stand-alone ozonation and photocatalytic oxidation process. Progress of the dye oxidation was followed by UV-VIS spectrophotometric measurements at controlled operating conditions. The organic content of reaction samples was measured to verify the process efficiency in dye mineralization. According to current results, almost complete color removal was obtained for ozonation within about 1 h reaction time. The reduction of the organic load was almost 80% from its original while initial sulphur content decreased to 32.5%. Dye conversion of 100% was obtained by means of a photocatalytic process using TiO2 as catalyst at 294 nm irradiated UV light. This complete color removal for the catalytic process was observed within 7 min of reaction time. The calculated initial rate of reaction of photocatalysis treatment was 8 times faster than that of ozonolysis. However, the remaining organic load of photocatalysis was almost 88% from its original while the final sulphur content was 27.3%. This contrasting behavior of the performance of the type of oxidation process stressed importance of physicochemical phenomena and intermediates molecules present during dye degradation. An insightful and mechanistic aspect of the dye oxidation was developed by performing quantumchemical calculations.

关键词： Indigo Potassium Tetrasulfonate Advanced Oxidation Processes Chemical Degradation Theoretical Calculations

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Single Step Microwave Assisted Synthesis and Antimicrobial Activity of Silver, Copper and Silver-Copper Nanoparticles

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j.urnal of Materials Science and Chemical Engineering 2020年第8期8卷 13-29页

作者： Myrna Reyes-Blas Nadj. M. Maldonado-Luna Carla M. Rivera-Quiñones Ana L. Vega-Avila Felix R. Roman-Velázquez Oscar j. Perales-perez Department of Chemistry University of Puerto Rico at Mayagüez Mayaguez USA Department of Mechanical Engineering University of Puerto Rico at Mayagüez Mayaguez USA Department of Chemical Engineering University of Puerto Rico at Mayagüez Mayaguez USA Department of Engineering Science & Materials University of Puerto Rico at Mayagüez Mayaguez USA

Copper and silver nanoparticles were synthesized and characterized in two minutes at 175°C in a one-step synthesis using a modified polyol (ethylene glycol) method and a microwave heating process. We successfully synthesized spherical Silver (Ag) and Copper nanoparticles (CuNP) with a crystallite size of less than 10 nm, as well as irregular silver-copper nanoparticles (AgCuNP) with a crystallite size of less than 15 nm, as confirmed by X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscopy (HRTEM). The successful synthesis of AgCuNP with 1:1 molar ratio and constituted by 51.74% of copper and 48.26% of silver was corroborated using the Energy Dispersive X-ray (EDX) mapping technique. The AgNP and AgCuNP exhibited more stability in suspension, in comparison to CuNP, as observed by continuously monitoring the absorbance with UV-Vis spectroscopy for 12 days. Furthermore, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of AgNP, CuNP, and AgCuNP were determined, against Gram-negative and Gram-positive bacteria, and yeast. The obtained MIC and MBC values indicate that AgCu nanoparticles exhibited bactericidal properties greater than its constituents. On the contrary, antifungal activity of AgCuNP against yeast was not observed.

关键词： Ag Nanoparticles Cu Nanoparticles Microwave Synthesis Modified Polyol Method Antimicrobial Properties AgCu Nanoparticles

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The Deep Thioredoxome in Chlamydomonas reinhardtii： New Insights into Redox Regulation

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Molecular Plant 2017年第8期10卷 1107-1125页

作者： Maria Esther perez-perez Adeline Mauries Alexandre Maes Nicolas j. Tourasse Marion Hamon Stephane D. Lemaire Christophe H. Marchand Institut de Biologie Physico-Chimique UMR8226 CNRS Sorbonne Universit6s UPMC Univ Paris 06 13 rue Pierre et Marie Curie 75005 Paris France Institut de Biologie Physico-Chimique Plateforme de Proteomique FRC550 CNRS 13 rue Pierre et Marie Curie 75005 Paris France Instituto de Bioquimica Vegetal y Fotosintesis Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad de Sevilla Seville Spain ARNA Laboratory INSERM U1212 CNRS UMR5320 Universite Bordeaux 2 Bordeaux France

Thiol-based redox post-translational modifications have emerged as important mechanisms of signaling and regulation in all organisms, and thioredoxin plays a key role by controlling the thiol-disulfide status of target proteins. Recent redox proteomic studies revealed hundreds of proteins regulated by glutathio- nylation and nitrosylation in the unicellular green alga Chlamydomonas reinhardtii, while much less is known about the thioredoxin interactome in this organism. By combining qualitative and quantitative proteomic analyses, we have comprehensively investigated the Chlamydomonas thioredoxome and 1188 targets have been identified. They participate in a wide range of metabolic pathways and cellular pro- cesses. This study broadens not only the redox regulation to new enzymes involved in well-known thiore- doxin-regulated metabolic pathways but also sheds light on cellular processes for which data supporting redox regulation are scarce （aromatic amino acid biosynthesis, nuclear transport, etc）. Moreover, we char- acterized 1052 thioredoxin-dependent regulatory sites and showed that these data constitute a valuable resource for future functional studies in Chlamydomonas. By comparing this thioredoxome with proteomic data for glutathionylation and nitrosylation at the protein and cysteine levels, this work confirms the existence of a complex redox regulation network in Chlamydomonas and provides evidence of a tremendous selectivity of redox post-translational modifications for specific cysteine residues.

关键词： Chlamydomonas reinhardtii disulfide bond isotope-coded affinity tag redox proteomics redox regulation thioredoxin targets

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Overcoming thermo-optical dynamics in broadband nanophotonic sensing

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Microsystems & Nanoengineering 2021年第4期7卷 47-57页

作者： Mingkang Wang Diego j.perez-Morelo Vladimir Aksyuk Microsystems and Nanotechnology Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Institute for Research in Electronics and Applied Physics University of MarylandCollege ParkMD 20742USA

Advances in integrated photonics open up exciting opportunities for batch-fabricated optical sensors using high-quality-factor nanophotonic cavities to achieve ultrahigh sensitivities and *** sensitivity improves with increasing optical power;however,localized absorption and heating within a micrometer-scale mode volume prominently distorts the cavity resonances and strongly couples the sensor response to thermal dynamics,limiting the sensitivity and hindering the measurement of broadband time-dependent ***,we derive a frequency-dependent photonic sensor transfer function that accounts for thermo-optical dynamics and quantitatively describes the measured broadband optomechanical signal from an integrated photonic atomic force microscopy nanomechanical *** this transfer function,the probe can be operated in the high optical power,strongly thermo-optically nonlinear regime,accurately measuring low-and intermediate-frequency components of a dynamic signal while reaching a sensitivity of 0.7fm/Hz^(1/2) at high frequencies,an improvement of=10x relative to the best performance in the linear ***,we discover that a higher transduction gain and sensitivity are achieved with lower quality-factor optical modes for low signal *** limited to optomechanical transducers,the derived transfer function is generally valid for describing the small-signal dynamic responses of a broad range of technologically important photonic sensors subj.ct to the thermo-optical effect.

关键词： dynamics regime hinder

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