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Bulk and surface damages in complementary bipolar junction transistors produced by high dose irradiation

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Chinese Physics B 2018年第1期27卷 430-437页

作者： j Assaf Atomic Energy Commission Damascus Syria

Two complementary types NPN and PNP of bipolar junction transistors （BjTs） were exposed to higll dose of neutrons and gamma rays. The change in the base and collector currents, minority carriers lifetime, and current gain factor/3 with respect to the dose were analyzed. The contributions of the base current according to the defect types were also reported. It was declared that the radiation effect of neutrons was almost similar between the two transistor types, this effect at high dose may decrease the value of/3 to less than one. The Messenger-Spratt equation was used to describe the experimental results in this case. However, the experimental data demonstrated that the effect of gamma rays was generally higher on NPN than PNP transistors. This is mainly attributed to the difference in the behavior of the trapped positive charges in the SiO2 layers. Meanwhile, this difference tends to be small for high gamma dose.

关键词： bipolar junction transistors radiation effects surface damage bulk damage

Subpulse Drifting of PSR j1110–5637

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Research in Astronomy and Astrophysics 2022年第6期22卷 109-117页

作者： S.j.Dang L.H.Shang L.Lin Q.j.Zhi R.S.Zhao C.B.Wu Z.Y.You A.j.Dong j.T.Bai X.Xu D.D.Zhang H.Yang Q.W.Lin School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China School of Physics Science and Technology Xinjiang UniversityUrumqi 830011China

We report a detailed study of polarization characteristics and subpulse drifting in PSR j1110-5637 with the observations of the Parkes 64 m radio telescope at 1369 *** observations revealed that the trailing component of the pulse profile has obvious subpulse drifting,while the leading component has no subpulse *** the two-dimensional fluctuation spectrum(2DFS),we detected three distinct emission modes in the trailing component(modes A,B and C).The emission in mode A is chaotic and indistinguishable,while modes B and C have obvious subpulse *** vertical modulation periods P3of modes B and C are around the mean values of 12 P and 8 P,*** subpulse drifting of PSR j1110-5637 will expand the pulsar sample with multiple subpulse drifting rates,and this will help future systematic studies on the physical origin of the subpulse drifting phenomenon.

关键词： (stars:)pulsars general-(stars:)pulsars individual(PSR j1110-5637)-Stars

General aspects on structural integrity

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Chinese journal of Aeronautics 2019年第1期32卷 114-132页

作者： j.j.XIONG R.A.SHENOI School of Transportation Science and Engineering Beihang University Faculty of Engineering and Environment University of Southampton

This paper seeks to mark the fruitful collaborative research between scholars in the University of Southampton and Beihang University for last 25 years on structural integrity. Their efforts addressed some important issues in structural integrity such as fatigue and fracture behavior,fatigue load spectra, fatigue and fracture lifetimes, reliability-based service period, adhesively bonded composite patch repairs, Plain Woven Fabric(PWF) composites and composite *** advances in engineering approaches, experimental methods, numerical algorithms and understanding of failure mechanisms relating to structural integrity are highlighted. Probable limits(or drawbacks) are also discussed. This review provides an insight into the general aspects on structural integrity and constitutes a basis for pointers to the further works on structural integrity.

关键词： Composites Fatigue Fracture Reliability Repair Structural integrity

Double sided roll-to-roll manufacture of flexible display panels

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Instrumentation 2015年第1期2卷 57-64页

作者： C.williamson H.-L.Liang Stuart Speakman D.Chu Centre for Advanced Photonics and Electronics Engineering DepartmentUniversity of Cambridge Institute of Engineering and Technology(FIET)

A double sided roll-to-roll(R2R) system has been developed by the authors to automate the continuous manufacturing of flexible display *** we report an overview of the system operation and the fabrication *** system framework features a timer initiated slot-die coating followed by wet lamination to form a thin,active layer in between flexible conductive substrates.A rotary screen-printing unit is installed for adhesive deposition providing an edge seal for the *** system enables production of 15-cm^2 laminated panels.

关键词： Roll-to-roll displays manufacturing liquid crystal printing flexible

Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research International 2022年第5期29卷 819-835页

作者： j.L.Guo T.j.Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were *** results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more *** softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface *** vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing *** is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is *** behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

Tomato Plants Overexpressing a Celery Mannitol Dehydrogenase (MTD) Have Decreased Susceptibility to <i>Botrytis cinerea</i>

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American journal of Plant Sciences 2015年第8期6卷 1116-1125页

作者： Takshay K. Patel Sergei F. Krasnyanski George C. Allen Frank j. Louws Dilip R. Panthee john D. williamson Department of Horticultural Science North Carolina State University Raleigh NC USA Department of Plant Pathology North Carolina State University Raleigh NC USA

The oxidative burst is a critical early event in plant-pathogen interactions that leads to a localized, programmed cell death (PCD) called the hypersensitive response (HR). The HR and associated PCD retard infection by biotrophic pathogens, but can, in fact, enhance infection by necrotrophic pathogens like Botrytis cinerea. In addition to signaling the induction of the HR, reactive oxygen species (ROS) produced during the oxidative burst are?antimicrobial. We hypothesize that pathogens such as B. cinerea survive the antimicrobial effects of ROS, at least partially by secreting the antioxidant mannitol during infection. This is supported by the previous observation that overexpression of the catabolic enzyme mannitol dehydrogenase (MTD) can decrease a plants susceptibility to mannitol-secreting pathogens like B. cinerea. To extend the above hypothesis, and test the general utility of this approach in an important horticultural crop, we overexpressed celery MTD in tomato (Solanum lycopersicum cv. “Moneymaker”). In these studies, we observed a significant increase (up to 90%) in resistance to B. cinerea in transgenic tomatoes expressing high amounts of MTD.

关键词： Hypersensitive Response Pathogenesis Response Plant-Pathogen Interaction Programmed Cell Death Reactive Oxygen Species

A study on distributive and modular lattice ordered fuzzy soft group and its duality

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Applied Mathematics(A journal of Chinese Universities) 2016年第4期31卷 491-502页

作者： j Arockia Reeta j Vimala Department of Mathematics Alagappa University

Soft set theory has a rich potential application in several fields. A soft group is a parameterized family of subgroups and a fuzzy soft group is a parameterized family of fuzzy subgroups. The concept of fuzzy soft group is the generalization of soft group. Abdulkadir Aygunoglu and Halis Aygun introduced the notion of fuzzy soft groups in 2009[1]. In this paper, the concept of lattice ordered fuzzy soft groups and its duality has been introduced. Then distributive and modular lattice ordered fuzzy soft groups are analysed. The objective of this paper is to study the lattice theory over the collection of fuzzy soft group in a parametric manner. Some pertinent properties have been analysed and hence established duality principle.

关键词： Fuzzy soft set fuzzy soft group lattice ordered fuzzy soft groups distributive lattice orderedfuzzy soft groups modular lattice ordered fuzzy soft groups.

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Accuracy details in realistic CFD modeling of an industrial centrifugal pump in direct and reverse modes

作者： j.·威廉逊(j. williamson) F.·波尔(F. Pohl)

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journal of Thermal Science 2010年第6期19卷 491-499页

作者： j.C. Páscoa F. j. Silva j.S. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores S.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. Conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using Spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling Spalart-Allmaras PAT