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structural Tuning of Low Band Gap Intermolecular Push/Pull side-chain Polymers for Organic Photovoltaic Applications

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Chinese Journal of Polymer science 2017年第9期35卷 1073-1085页

作者： Ansuman nayak P.s. Rama sreekanth s.n.osh Kumar sahu Duryodhan sahu Department of Chemistry National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008 Department of Chemistry Gandhi Institute of Engineering and Technology Gunpur Odisha India Department of Mechanical Engineering National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008

A series of novel low band gap donor-acceptor （D-A） type organic co-polymers （BT-F-TPA, BT-CZ-TPA and BT-sI-TPA） consisting of electron-deficient acceptor blocks both in main chains （M1） and at the pendant （M2） were polymerized with different electron rich donor （M3-M5） blocks, i.e., 9,9-dihexyl-9H-fluorene, n-alkyl-2,7-carbazole, and 2,6-dithinosilole, respectively, via suzuki method. These polymers exhibited relatively low band gaps （1.65-1.88 eV） and broad absorption ranges （680-740 nm）. Bulk heterojunction （BHJ） solar cells incorporating these polymers as electron donors, blended with [6,6]-phenyl-C61-butyric acid methyl ester （PC61BM） or [6,6]-phenyl-Cvl-butyric acid methyl ester （PC71BM） as electron-acceptors in different weight ratios were fabricated and tested under 100 mW/cm2 of AM 1.5 with white-light illumination. The photovoltaic device containing donor BT-sI-TPA and acceptor PC71BM in 1：2 weight ratio showed the best power conversion efficiency （PCE） value of 1.88%, with open circuit voltage （Voc） = 0.75 V, short circuit current density （Jsc） = 7.60 mA/cm2, and fill factor （FF） = 33.0%.

关键词： Polymer solar cells Low band gap Conducting polymers Charge transfer Donor-acceptor Bulk heterojunctionsolar cell

Microwave Dried Carrot Pomace as a source of Fiber and Carotenoids

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Food and nutrition sciences 2013年第10期4卷 1037-1046页

作者： Marcela Hernández-Ortega Guy Kiss.n.ou Hugo necoechea-Mondragón María Elena s.n.hez-Pardo Alicia Ortiz-Moreno Coordinación de Cooperación Académica Edificio de la Secretaría Académica Instituto Politécnico Nacional México City México. Departamento de Ingeniería Bioquímica Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México City México

Carrot pomace is a major by-product obtained during the industrial juice extraction process, which is discarded contributing to environmental pollution. This residue is rich in fiber, and contains high amounts of carotenoids and phenolic compounds that could contribute to its application as functional ingredient, improving the quality of foods and helping to reduce the environmental problem. In this study, carrot pomace powders obtained by microwave or hot air drying were incorporated into cookies in order to improve their phytochemical content. Cookies were prepared us.n. a traditional cookie recipe substituting 30% of the wheat flour for either of the carrot pomace powders. Fiber, carotenoids and phenolic compounds were determined;image analysis and acceptability of the cookies were also conducted. The substitution of 30% of wheat flour for carrot pomace powders increased 3.7 fold the total dietary fiber of cookies, from 7.13 g/100gto26.44 g/100g;accounting the 7.4% of fiber daily intake with the consumption of one cookie (7 g). A similar pattern was found in the content of carotenoids and phenolic compounds. Carrot pomace dried with microwaves had the highest amount of these bioactive compounds. β-carotene, epicatechin, gallic and ferulic acids were identified in cookies with microwave carrot pomace powder. The cookies incorporated with carrot pomace powders exhibited improved antioxidant properties because of the increase in the phytochemical content. Acceptable cookies with appealing orange color were obtained. The results indicated that the replacement of wheat flour for carrot pomace powders yielded dietary fiber enriched cookies with improved carotenoid content.

关键词： Carrot Pomace Microwave Drying Fiber Carotenoids Phenolic Compounds Antioxidant Activity Cookie

Effect of Baroclinicity on Vortex Axisymmetrization. Part Ⅰ:Barotropic Basic Vortex

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Advances in Atmospheric sciences 2014年第6期31卷 1256-1266页

作者： Melinda s.PEnG Jiayi PEnG Tim LI Eric HEnDRICKs naval Research Laboratory Monterey California USA IMsG at Environmental Modeling Center NCEP/NOAA College Park Maryland USA Department of Meteorology and IPRC University of Hawaii at Manoa Honolulu Hawaii USA

The barotropic and baroclinic disturbances axisymmetrized by the barotropic basic vortex are examined in an idealized modeling framework consisting of two *** a Wentzel-Kramers-Brillouin approach,the radial propagation of a baroclinic disturbance is shown to be slower than a barotropic disturbance,resulting in a slower linear axisymmetrization for baroclinic *** slower-propagating baroclinic waves also cause more baroclinic asymmetric kinetic energy to be transferred directly to the barotropic symmetric vortex than from barotropic disturbances,resulting in a faster axisymmetrization process in the nonlinear baroclinic wave case than in the nonlinear barotropic wave case.

关键词： vortex axisymmetrization asymmetry baroclinicity

Effect of Baroclinicity on Vortex Axisymmetrization. Part Ⅱ:Baroclinic Basic Vortex

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Advances in Atmospheric sciences 2014年第6期31卷 1267-1278页

作者： Jiayi PEnG Melinda s.PEnG Tim LI Eric HEnDRICKs IMsG at Environmental Modeling Center NCEP/NOAA College Park Maryland USA naval Research Laboratory Monterey California USA Department of Meteorology and IPRC University of Hawaii at Manoa Honolulu Hawaii USA

The effect of baroclinicity on vortex axisymmetrization is examined within a two-layer dynamical *** basic state vortices are constructed with varying degrees of baroclinicity：（i） barotropic,（ii） weak baroclinic,and （iii） strong *** linear and nonlinear evolution of wavenumber-2 baroclinic disturbances are examined in each of the three basic state *** results show that the radial propagating speed of the vortex Rossby wave at the lower level is larger with the stronger baroclinicity,resulting in a faster linear axisymmetrization process in the stronger baroclinic *** is found that the nonlinear axisymmetrization process takes the longest time in the strongest baroclinic vortex among the three different basic vortices due to the weaker kinetic energy transfer from asymmetric to symmetric circulations at the lower level.A major finding in this study is that the same initial asymmetric perturbation can have different effects on symmetric vortices depending on the initial vortex *** numerical weather prediction models,this implies that there exists a s.n.itivity of the subsequent structural and intensity change solely due to the specification of the initial vertical shear of the tropical cyclone vortex.

关键词： vortex axisymmetrization asymmetry baroclinicity

沉积砂的质量和成岩作用对孔隙度和渗透率的影响:来自北海北部布伦特群储集层的例子

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海洋地质译丛 1998年第1期 26-29页

作者： s.n.Ehrenberg 王桥

1引言通常石油公司对砂岩储集层作岩石学研究，以便了解控制岩石物理性质，特别是孔隙度和渗透率的因素。本文综合了这两种研究结果。两次研究原先是独立进行的，但关于采样对策、分析技术和解释却运用了相似方法。对这两套资料的科学... 详细信息

1引言通常石油公司对砂岩储集层作岩石学研究，以便了解控制岩石物理性质，特别是孔隙度和渗透率的因素。本文综合了这两种研究结果。两次研究原先是独立进行的，但关于采样对策、分析技术和解释却运用了相似方法。对这两套资料的科学兴趣在于所观测的定量岩石学测量值和孔隙度一渗透率变化之间的相关趋势。这种关系为估算控制孔隙度和渗透率的不同岩石过程相对重要性提供了基础。所研究灼砂岩单元在岩性和岩石物理性质方面在短的垂直层段内变化很大。这些变化与由“沉积砂质量”决定的孔隙系统特征的变化趋势有关，在这里定义的沉积砂质量为如下两种联合因素对储集层质量（孔隙度、渗透率和饱和特征）的有效影响：（1）原始的砂组份和结构，（2）反映沉积环境控制因素（包括与海底有关的胶结作用和形成土壤的过程）的早期成岩过程。所考察的一套资料来自较浅深度，受到化学成岩作用影响较小，而第二套资料来自较深埋藏的储集层，它具有较深程度的晚期成岩作用。因此两套资料间的对比可提供关于沉积学控制的孔隙一渗透率分布如何受埋藏成岩作用影响的信息。考察储集层质量与岩石的场域内关系对理解区域孔隐度一渗透率一深度变化趋势的平均值和分散值的意义是有好处的（BOCh，1991）。在砂岩成...

关键词：沉积砂质量成岩作用孔隙度储集层油田

Outgass.n. from internal adhesive joints of vacuum devices

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Journal of Measurement science and Instrumentation 2017年第4期8卷 347-353页

作者： Boris s Lunin Valerii A Kreisberg Yurii n Zhitnev Evgenia A Tveritinova Mikhail A Basarab Robert A Zakharyan Department of Chemistry M.V. Lomonosov Moscow State University Moscow 119991 Russia Department of Information systems and Telecommunications Bauman Moscow State Technical University Moscow 105005 Russia Tarussky Branch of A.M. Prokhorov General Physics Institute Tarusa 249100 Russia

Kinetics of the formation of residual atmosphere in vacuum devices with internal adhesive joints and the application of the mass spectral and chromatographic methods to measure the specific outgass.n. rate of volatile compounds from the cured adhesives are considered in this *** outgass.n. comparis.n.data for the various types of adhesives are given and the effectiveness of the outgass.n. of adhesive joints is *** possible options to provide vacuum in the various devices are *** moderate requirements to the residual pressure(about10-2Pa),it is enough to degass the adhesive joints during a few *** is much more difficult to provide vacuum in devices with internal adhesive joints at the level of *** requires the use of the built-in getter and the high temperature *** is expedient to provide deep vacuum(10-5-10-4Pa)in the rare-used or once-used devices by short(a few minutes)activation the built-in getters before operating the vacuum *** allows to remove the main residual gas hydrocarbons component from the vacuum house and provide the necessary level of vacuum for a certain interval of time.

关键词： outgass.n. adhesive vacuum device

Epigenetic basis of Alzheimer disease

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World Journal of Biological Chemistry 2020年第2期11卷 62-75页

作者： Angeles C Tecalco-Cruz JosuéO Ramírez-Jarquín María E Alvarez-s.n.hez Jesus Zepeda-Cervantes Programa en Ciencias Genómicas Universidad Autónoma de la Ciudad de MéxicoMexico 03100Mexico División de neurociencias Instituto de Fisiología CelularUniversidad Nacional Autónoma de MéxicoMexico 04510Mexico Posgrado en Ciencias Genómicas Universidad Autónoma de la CiudadMexico 03100Mexico Biología celular y de desarrollo Instituto de Fisiología CelularUniversidad Nacional Autónoma de MéxicoMexico 04510Mexico

Alzheimer disease(AD)is the primary form of dementia that occurs spontaneously in older ***,the epigenetic profile of the cells forming the central nervous system changes during aging and may contribute to the progression of some neurodegenerative diseases such as *** this review,we pres.n. general insights into relevant epigenetic mechanisms and their relationship with aging and *** data suggest that some epigenetic changes during aging could be utilized as biomarkers and target molecules for the prevention and control of AD.

关键词： Epigenetics Aging neurodegenerative diseases Alzheimer disease

Bright Red Luminescence and structural Properties of Eu<sup>3+</sup>Ion Doped ZnO by solution Combustion Technique

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World Journal of Condensed Matter Physics 2014年第4期4卷 227-234页

作者： sebastián López-Romero María Jesús Quiroz-Jiménez Manuel Hipólito García Alfredo Aguilar-Castillo Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de México Circuito Interior S/N Ciudad Universitaria México México D.F. México

Pure, and Europium ion doped Zinc oxide nanocrystals (ZnO:Eu3+) were s.n.hesized by a solution combustion technique. The X-ray diffraction patterns (XRD) reveals the existence of the Eu2O3 phase. From the results of both, X-ray diffraction and photoluminescence spectra (PL) reveal that Eu3+ ions successfully substitute for Zn2+ ions in the ZnO lattice, moreover, when the amount of doped Europium was varied, this changes are showed in changes in the luminescence intensity. The PL is broad and a set of colors was emitted which originates from ZnO and the intra 4f transitions of Eu3+ ions. The existence of the Zn-O, Eu3+-O and O1s bonding energies were confirmed by X-ray photoelectron spectroscopy (XPs) technique. The samples morphology was registered by a scanning electron microscopy (sEM) technique, and reveals that Europium ions are pres.n. on the surface of the ZnO nanocrystals.

关键词： ZnO Europium Ion solution Combustion Photoluminescence

FREE TRAnsVERsE VIBRATIOns OF A DOUBLE-WALLED CARBOn nAnOTUBE:GRADIEnT AnD InTERnAL InERTIA EFFECTs

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Acta Mechanica solida s.n.ca 2014年第4期27卷 345-352页

作者： K.Y.Xu K.A.Alnefaie n.H.Abu-Hamdeh K.H.Almitani E.C.Aifantis Department of Mechanics Shanghai University Department of Mechanical Engineering King Abdulaziz University Jeddah 21589 Saudi Arabia Lab of Mechanics and Materials Polytechnic School Aristotle University Thessaloniki 54124 Greece

This is a modest contribution on higher-order continuum theory for predicting size effects in small-scale objects. It relates to a preceding article of the journal by the same authors（AMss, 2013, 26： 9-20） which considered the longitudinal dynamical analysis of a gradient elastic fiber but, in addition to an internal length, an internal time parameter is also introduced to model delay/acceleration effects associated with the underlying microstructure. In particular, the free transverse vibration of a double-walled carbon nanotube（DWnT） is studied by employing gradient elasticity with internal inertia. The inner and outer carbon nanotubes are modeled as two individual elastic beams interacting with each other through van der Waals（vdW） forces. General explicit expressions are derived for the natural frequencies and the associated inner-to-outer tube amplitude ratios for the case of simply supported DWnTs. The effects of internal length（or scale）and internal time（or inertia） on the vibration behavior are evaluated. The results indicate that the internal length and time parameters of the adopted strain gradient-internal inertia generalized elasticity model have little influence on the lower order coaxial and noncoaxial vibration modes,but a significant one on the higher order modes.

关键词： carbon nanotubes gradient elasticity internal inertia vibration behavior