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Chinese Physics B 2014年第7期23卷 417-428页

作者： H R Baghshahi M k.Tavassoly A Behjat Atomic and Molecular Group Faculty of PhysicsYazd University The Laboratory of Quantum Information Processing Yazd University Department of Physics Faculty of ScienceVali-e-Asr University of Rafsanjan Photonics Research Group Engineering Research CenterYazd University

The interaction between a two-level atom and a single-mode field in the k.photon Jaynes-Cummings model （JCM） in the presence of the Stark.shift and a k.rr medium is studied. All terms in the Hamiltonian, such as the single-mode field, its interaction with the atom, the contribution of the Stark.shift and the k.rr medium effects are considered to be f-deformed. In particular, the effect of the initial state of the radiation field on the dynamical evolution of some physical properties such as atomic inversion and entropy squeezing are investigated by considering different initial field states （coherent, squeezed and thermal states）.

关键词： Jaynes-Cummings model entropy squeezing atomic inversion intensity-dependent coupling

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德里达眼中的艺术

Design optimisation for distance between additional and tap winding in high-voltage transformers

作者： (美)k. 马尔科姆·理查兹(k. Malcolm Richards)

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High Voltage 2020年第6期5卷 716-723页

作者： k.mran Dawood Ahmet k.rem k.seoğlu Güven k.mürgöz Department of Electrical Engineering Istanbul Technical UniversityIstanbulTurkey Best Transformers BalıkesirTurkey

The transformer is one of the main components in the power network.and transformer windings are one of the most expensive elements in the power transformer. Optimisation of winding distances is one of the most important parameters during the manufacturing of transformer. The distance between the windings in the two winding transformers is well k.own to transformer designers and manufacturers. However, insulation of the high voltage transformer with additional winding and tap winding is still a major problem for transformer designers. In this study, the additional winding to tap winding distance optimisation is made for a high voltage power transformer. Optimisation of the transformer's windings just not minimises the cost of the transformer but also increases the lifetime of the transformer. With additional winding and tap winding in high-voltage transformers, insulation distance is a major concern for minimising the cost and size of the high voltage transformer. In this study, an approach is made to balance the cost, size, and safety of high voltage transformers. The optimised distance and position between tap winding and additional winding are determined by using the finite element analysis. The finite element method results were also verified by mak.ng a prototype transformer.

关键词： winding insulation high

Contribution of precursor compounds to the release of per-and polyfluoroalk.l substances(PFASs) from waste water treatment plants(WWTPs)

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Journal of Environmental Sciences 2017年第11期29卷 80-90页

作者： Ulrik. Erik.son Peter Haglund Anna k.rrman Man-Technology-Environment (MTM) Research Centre School of Science and Technology ?rebro University Department of Chemistry Umea University

Per-and polyfluoroalk.l substances（PFASs） are ubiquitous in sludge and water from waste water treatment plants, as a result of their incorporation in everyday products and industrial processes. In this study, we measured several classes of persistent PFASs,precursors, transformation intermediates, and newly identified PFASs in influent and effluent sewage water and sludge from three municipal waste water treatment plants in Sweden, sampled in 2015. For sludge, samples from 2012 and 2014 were analyzed as *** of precursors in sludge exceeded those of perfluoroalk.l acids and sulfonic acids（PFCAs and PFSAs）, in 2015 the sum of polyfluoroalk.l phosphoric acid esters（PAPs） were 15–20 ng/g dry weight, the sum of fluorotelomer sulfonic acids（FTSAs） was 0.8–1.3 ng/g,and the sum of perfluorooctane sulfonamides and ethanols ranged from non-detected to 3.2 ng/g. Persistent PFSAs and PFCAs were detected at 1.9–3.9 ng/g and 2.4–7.3 ng/g dry weight, respectively. The influence of precursor compounds was further demonstrated by an observed substantial increase for a majority of the persistent PFCAs and PFSAs in water after waste water treatment. Perfluorohexanoic acid（PFHxA）, perfluorooctanoic acid（PFOA）, perfluorohexane sulfonic acid（PFHxS）, and perfluorooctane sulfonic acid（PFOS）had a net mass increase in all WWTPs, with mean values of 83%, 28%, 37% and 58%,respectively. The load of precursors and intermediates in influent water and sludge combined with net mass increase support the hypothesis that degradation of precursor compounds is a significant contributor to PFAS contamination in the environment.

关键词： diPAPs FTSAs Waste water Daily discharge PFCA precursor

Rayleigh-type wave propagation through liquid layer over corrugated substrate

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Applied Mathematics and Mechanics(English Edition) 2017年第6期38卷 851-866页

作者： A.k.SINGH A.DAS A.RAY Department of Applied Mathematics Indian Institute of Technology(ISM)

The propagation of the Rayleigh-type wave in a fluid layer overlying a corrugated substrate is studied. The corrugated substrate is considered as a fluid satu- rated poroelastic substrate and a quadratically heterogeneous isotropic elastic substrate in Case I and Case II, respectively. Closed form expressions of dispersion relation for Case I and Case II ave obtained. The influence of corrugation, porosity, and hetero- geneity on the phase velocity of Rayleigh-type wave, for both cases, is highlighted and demonstrated through numerical computation and graphical discussion. Neglecting cor- rugation at the common interface, expressions of phase velocity of the Rayleigh-type wave for both cases ave derived in a closed form as a special case of the problem. Comparison between the presence and the absence of both heterogeneity and poroelasticity in the substrate of the composite structure is a k.y in the present study.

关键词： Rayleigh-type wave porosity heterogeneity corrugation

Decision tree and deep learning based probabilistic model for character recognition

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Journal of Central South University 2017年第12期24卷 2862-2876页

作者： A.k.Sampath Dr.N.Gomathi Rizvi College of Engineering MumbaiMaharashtra 400050India Veltech Dr.R.R&Dr.S.R.Technical University Avadi Chennai-600 062India

One of the most important methods that finds usefulness in various applications, such as searching historical manuscripts, forensic search, bank.check.reading, mail sorting, book.and handwritten notes transcription, is handwritten character recognition. The common issues in the character recognition are often due to different writing styles, orientation angle, size variation(regarding length and height), etc. This study presents a classification model using a hybrid classifier for the character recognition by combining holoentropy enabled decision tree(HDT) and deep neural network.DNN). In feature extraction, the local gradient features that include histogram oriented gabor feature and grid level feature, and grey level co-occurrence matrix(GLCM) features are extracted. Then, the extracted features are concatenated to encode shape, color, texture, local and statistical information, for the recognition of characters in the image by applying the extracted features to the hybrid classifier. In the experimental analysis, recognition accuracy of 96% is achieved. Thus, it can be suggested that the proposed model intends to provide more accurate character recognition rate compared to that of character recognition techniques used in the literature.

关键词： grey level co-occurrence matrix feature histogram oriented gabor gradient feature hybrid classifier holoentropy enabled decision tree classifier

锥角堆积模型应用——f电子组元素新类型金属有机化合物的推测与合成

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化学学报 1984年第11期42卷 1214-1217页

作者：李醒夫 Fischer,R.D Bagnall,k. W. 中国科学院高能物理所应用部 Institute Department of Chemistry University of Manchester England 北京 für Anorganische und Angewandte Chemie Universit(?)t Hamburg

过渡金属有机化合物一般遵守18或16电子规律.但对于d电子组的前几个元素(Ti,Zr,Hf)和f电子组元素却并不如此.Mark.提出过:铀(IV)、钍(IV)的某些有机化合物分别遵循20或22电子规律.但这种观点无法解释许多实际存在的化合物.我们在最近提... 详细信息

过渡金属有机化合物一般遵守18或16电子规律.但对于d电子组的前几个元素(Ti,Zr,Hf)和f电子组元素却并不如此.Mark.提出过:铀(IV)、钍(IV)的某些有机化合物分别遵循20或22电子规律.但这种观点无法解释许多实际存在的化合物.我们在最近提出:当配位场作用很弱时,空间堆积作用是不容忽视的.在中心离子周围配位体的堆积达到一定程度时,尽管从表观上看,中心离子的外层电子与配位电子数之和还没有达到“下一级惰性气体结构”,但配位体之间的相互推斥作用阻止了更多的配体进入配位层.从几何角度来进行研究时,这种由空间堆积效应与成键效应达成的平衡应当表现为:化合物结构中配位体的立体角系数(Solid Angle Factor,Q/4π)之总和(SAS)分布在一个“稳定区间”之内.而后者的位置与金属的氧化态有关.我们先后对近300个已知的f电子组元素的配合物与金属有机化合物的结构进行了计算.结果表明中心离子周围的空间占据呈现“饱和”现象.饱和堆积程

关键词：金属有机化合物有机金属化合物中心离子堆积模型配阴离子配位层配位数配离子锥角电子轻子

Strain-induced formation of a gradient nanostructured surface layer on an ultrahigh strength bearing steel

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Journal of Materials Science & Technology 2018年第9期34卷 1676-1684页

作者： k.Zhang Z.B.Wang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

In the present work. an ultrahigh strength bearing steel（AISI 52100） was subjected to surface mechanical rolling treatment（SMRT） at room temperature. Microstructural observations showed that martensitic laths, twins and cementite particles in the initial microstructure underwent distinct plastic strains and were gradually refined into nanostructures. Consequently, a gradient nanostructured（GNS） surface layer with a mean grain size of -24 nm at the top surface was obtained on the bearing steel, resulting in an increment of -20% in the surface hardness. Analyses based on microstructural evolution, phase constitution and in-depth hardness distribution revealed a mechanically induced formation mechanism of the GNS surface layer. The multiple surface severe plastic deformation under fine lubrication and cooling during SMRT contributed to the formation of a thick.hardened surface layer on the bearing steel.

关键词： Gradient nanostructured Ultrahigh strength bearing steel Plastic deformation Martensite Surface mechanical rolling treatment

Geophysical signatures of Precambrian shields and suture zones: Preface for thematic section

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Geoscience Frontiers 2014年第1期5卷 1-2页

作者： k.Naganjaneyulu Engineering and Airborne Geophysics Division Council of Scientifc and Industrial Research e National Geophysical Research Institute (CSIR-NGRI)

The Precambrian shields and associated suture zones of the globe preserve important records of continental growth and destruction, the formation and closure of ocean basins, and the early evolution of the Earth in terms of tectonics, resources, and environment. They also offer critical clues on the nature and style of plate tectonics, mantle dynamics and crust-mantle interaction. In this thematic section of Geoscience Frontiers, a set of four contri- butions are assembled that provide a window to the mechanisms and processes in Precambrian shields and associated suture zones from a geological and geophysical perspective.

关键词： In Preface for thematic section Geophysical signatures of Precambrian shields and suture zones

Science and the practice of cardiovascular medicine in the geriatric population

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Journal of Geriatric Cardiology 2011年第2期8卷 67-71页

作者： Nanette k.Wenger Emory University School of Medicine Emory Heart and Vascular Center Atlanta GA 30303 USA

1 Why is the demograpy important? In the half century 2000-2050,there will be a virtual tsunami of aging in the United *** anticipated increase in the population older than age 65 is 140%,and for the population older than age 85,389%.More than half of the current *** can anticipate living to age 80,with a contemporary life expectancy at age 75 of 11 years,and at age 85 of 6 years.

关键词： cardiovascular medicine the aged clinical trials