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A rotating α-chain in the nucleus 12C

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 14-15页

作者： peter Ring Physics Department Technical University Munich State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University

Because of the strong nuclear force among protons and neutrons,α-particles form a stable configuration not only in free space, but also in very light nuclei. Even in unstable configurations of heavy and super-heavy nuclei,α-decay is often observed. Obviously there is a high probability for the formation of anα-particle in such systems, which tunnels through the Coulomb barrier as a combined particle.

关键词： A rotating chain in the nucleus

Effects of Electric Field on Electronic States in a GaAs/GaAlAs Quantum Dot with Different Confinements

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Chinese Physics Letters 2008年第8期25卷 3021-3024页

作者： A. John peter Vemuri Lakshminarayana Govt. Arts College Melur-625 106 Madurai India Mohamed Sathak Engineering College Kilakarai-623 806 Rarnnad India

Binding energies of shallow hydrogenic impurity in a GaAs/GaAlAs quantum dot with spherical confinement, parabolic confinement and rectangular confinement are calculated as a function of dot radius in the influence of electric field. The binding energy is calculated following a variational procedure within the effective mass approximation along with the spatial depended dielectric function. A finite confining potential well with depth is determined by the discontinuity of the band gap in the quantum dot and the cladding. It is found that the contribution of spatially dependent screening effects are small for a donor impurity and it is concluded that the rectangulax confinement is better than the parabolic and spherical confinements. These results are compared with the existing literature.

关键词： BINDING-ENERGY IMPURITY STATES HYDROGENIC IMPURITIES MAGNETIC-FIELDS DONOR STATES EXCITON GAAS-GA1-XALXAS CRYSTALLITES CLUSTERS GAAS

Decarbonising energy: The developing international activity in hydrogen technologies and fuel cells

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Journal of Energy Chemistry 2020年第12期29卷 405-415页

作者： John Meurig Thomas peter P.Edwards peter J.Dobson Gari P.Owend Department of Materials Science&Metallurgy University of CambridgeCambridge CB30FSUK King Abdulaziz City for Science and Technology(KACST)-Oxford Centre of Excellence in Petrochemicals and Inorganic Chemistry Laboratory University of OxfordOxford OX13QRUK The Queen’s College University of OxfordOxford OX14AWUK Annwvyn Solutions(Independent Consultant) BromleyKent BR13DWUK

Hydrogen technologies and fuel cells offer an alternative and improved solution for a decarbonised energy *** cells are electrochemical converters;transforming hydrogen (or energy sources containing hydrogen) and oxygen directly into *** hydrogen fuel cell,invented in 1839,permits the generation of electrical energy with high efficiency through a non-combustion,electrochemical process and,importantly,without the emission ofits point of ***,despite numerous efforts to exploit the obvious attractions of hydrogen technologies and hydrogen fuel cells,various challenges have been encountered,some of which are reviewed ***,however,given the exigent need to urgently seek low-carbon paths for humankind’s energy future,numerous countries are advancing the deployment of hydrogen technologies and hydrogen fuel cells not only for transport,but also as a means of the storage of excess renewable energy from,for example,wind and solar ***,hydrogen is also being blended into the natural gas supplies used in domestic heating and targeted in the decarbonisation of critical,large-scale industrial processes such as steel *** briefly review specific examples in countries such as Japan,South Korea and the People’s Republic of China,as well as selected examples from Europe and North America in the utilization of hydrogen technologies and hydrogen fuel cells.

关键词： Decarbonisation Hydrogen Energy Hydrogen Economy Fuel cells Environment Sustainability

Differential Kinematic Encoding of Saccades and Smooth-pursuit Eye Movements by Fastigial Neurons

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Neuroscience Bulletin 2022年第8期38卷 927-932页

作者： Zongpeng Sun peter W.Dicke peter Thier School of Psychology Shaanxi Normal UniversityXi’an710062China Department of Cognitive Neurology Hertie Institute for Clinical Brain Research72076TübingenGermany

Dear Editor,Saccades and smooth-pursuit eye movements(SPEMs)are two categories of eye movements with very different kinematics,in particular very different acceleration and velocity ranges,differences that have contributed to the notion of largely segregated underlying neuronal *** instance,it has been suggested that distinct wellsegregated pools of oculomotor vermis(OMV)Purkinje cells(PCs)are specialized for the fine-tuning of the relevant kinematic parameters characterizing each of them.

关键词： pursuit specialized instance

Biomimetic flexible plate actuators are faster and more efficient with a passive attachment

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Acta Mechanica Sinica 2016年第6期32卷 1001-1011页

作者： peter D.Yeh Alexander Alexeev George W.Woodruff School of Mechanical Engineering Georgia Institute of Technology

Using three-dimensional computer simulations, we probe biomimetic free swimming of an internally actuated flexible plate in the regime near the first natural frequency. The plate is driven by an oscillating internal moment approximating the actuation mechanism of a piezoelectric macro fiber composite (MFC) bimorph. We show in our simulations that the addition of a passive attachment increases both swimming velocity and efficiency. Specifically, if the active and passive sections are of similar size, the overall performance is the best. We determine that this optimum is a result of two competing factors. If the passive section is too large, then the actuated portion is unable to generate substantial deflection to create sufficient thrust. On the other hand, a large actuated section leads to a bending pattern that is inefficient at generating thrust especially at higher frequencies.

关键词： Flexible plate Biomimetic Lattice Boltzmann Fluid-structure interaction Robotic fish Piezoelectric actuator

A multivariable output neural network approach for simulation of plug-in hybrid electric vehicle fuel consumption

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Green Energy and Intelligent Transportation 2023年第2期2卷 66-84页

作者： Bukola peter Adedeji Department of Industrial Systems Engineering University of ReginaSKS4S 0A2Canada

This study is laser focused on the simulation of fuel consumption and fuel economy label parameters of plug-in hybrid electric *** fuel economy is a key factor in the design of plug-in hybrid electric vehicles,a fuel economy label can educate customers about the economic advantage of purchasing a particular *** fuel economy label of a PHEV consists of parameters like driving range,electrical energy consumption,fuel economy for city,highway,and combined use,battery recharge time,and fuel consumption *** study used an inverse function model of an artificial neural network to simulate and calculate the parameters of the fuel economy labels of ***,the selected parameters of the fuel economy label of plug-in hybrid electric vehicles were used to develop a single output *** output variable of the single output model was then merged with dummy functions to form input variables for the inverse function *** output variables simulated were engine size in litres;estimated driving range when the battery is fully charged in km,battery recharged time in hours,city fuel consumption(L/100 km),highway fuel consumption(L/100 km),combined fuel consumption(L/100 km),estimated driving range when the tank is full,carbon dioxide(CO_(2))emission in grams/km,electric motor power in kW,number of cylinders,and electrical charges consumed in kWh/100 *** cases of input variables were considered for the inverse function *** accuracy of the model was 29.1 times greater than that of the conventional inverse artificial neural network model.

关键词： Plug-in hybrid electric vehicles Fuel economy Fuel economy label Artificial neural network Simulation

Electronic and optical properties of CdS/CdZnS nanocrystals

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Chinese Physics B 2012年第8期21卷 441-448页

作者： A.John peter Chang Woo Lee epartment of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University1 SeochunGihungYonginGyeonggi 446-701S.Korea Department of Physics Govt.Arts CollegeMelurMadurai-62510India Department of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University1 SeochunGihungYonginGyeonggi 446-701S.Korea

Cd1-xZnxS nanocrystals are prepared by a co-precipitation method with different atomic fractions of Zn. The texture, structural transformation and optical properties with increasing x value in Cd1-xZnxS are studied with scanning electron microscopy, electron diffraction patterning, and absorption spectra respectively. Quantum confinement in a strained CdS/Cd1-xZnxS related nanodot with various Zn content values is investigated theoretically. Binding energies on exciton bound CdS/CdxZn1-xS quantum dot are computed, with consideration of the internal electric field induced by the spontaneous and piezoelectric polarizations, and thereby the interband emission energy is calculated as a function of the dot radius. The optical band gap from the UV absorption spectrum is compared with the interband emission energy computed theoretically. Our results show that the average diameter of composite nanoparticles ranges from 3 nm to 6 nm. The X-ray diffraction pattern shows that all the peaks shift towards the higher diffracting angles with an increase in Zn content. The lattice constant gradually decreases as the Zn content increases. The strong absorption edge shifts towards the lower wavelength region and hence the band gap of the films increases as the Zn content increases. The values of the absorption edge are found to shift towards the shorter wave length region and hence the direct band gap energy varies from 2.5 eV for the CdS film and 3.5 eV for the ZnS film. Our numerical results are in good agreement with the experimental results.

关键词： quantum dots quasicrystals semiconductor

Effective platform for the generation of aerosol droplets and application in evaluating the effectiveness of a MEMS-based nanoparticle trapping device

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Particuology 2009年第6期7卷 471-476页

作者： Ratna Tantra Dipak Gohil peter Cumpson National Physical Laboratory Hampton RoadTeddingtonMiddlesex TW11 0LWUnited Kingdom School of Mechanical and Systems Engineering Newcastle UniversityNewcastle-upon-Tyne NE1 7RUUnited Kingdom

The purpose of this study is two-fold： firstly, the development of a cheap, easy-to-construct and effective nanoparticle generator for testing nanoparticle sensors; secondly, the use of such a generator to test the effectiveness of a sensor device in trapping aerosolised nanoparticles. In this study, we have constructed an effective aerosol generator platform, based on aerosol-assisted chemical vapour deposition technology. Under well-controlled experimental conditions, this platform is capable of depositing aerosolised sodium chloride particles homogeneously on a substrate very effectively. Deposited aerosol droplets were subsequently dried and shown to form nanosized cubic crystals that are free from impurities. This platform was employed to test the effectiveness of a MEMS comb device in the electrostatic trapping of nanoparticles. Upon applying a DC bias （0.5 V） to the MEMS device, results showed an increase in nanoparticle deposition on the surface of the device, due to electrostatic precipitation. The presence of an electric field was shown to affect crystal formation upon drying of the aerosol droplets on the substrate; this caused a blotchy appearance on the SEM image, which was not observed in the absence of electric field.

关键词： Aerosol MEMS sensor Particle generator

Radiative life time of an exciton confined in a strained GaN/Ga_(1-x)Al_xN cylindrical dot:built-in electric field effects

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Chinese Physics B 2011年第7期20卷 367-372页

作者： Chang Woo Lee A.John peter Department of Chemical Engineering and Green Energy Center College of EngineeringKyung Hee University1 SeochunGihungYonginGyeonggi 446-701Republic of Korea Department of Physics Government Arts and Science CollegeMelur-625106India

The binding energy of an exciton in a wurtzite GaN/GaAlN strained cylindrical quantum dot is investigated theoretically. The strong built-in electric field due to the spontaneous and piezoelectric polarizations of a GaN/GaAlN quantum dot is included. Numerical calculations are performed using a variational procedure within the single band effective mass approximation. Valence-band anisotropy is included in our theoretical model by using different hole masses in different spatial directions. The exciton oscillator strength and the exciton lifetime for radiative recombination each as a function of dot radius have been computed. The result elucidates that the strong built-in electric field influences the oscillator strength and the recombination life time of the exciton. It is observed that the ground state exciton binding energy and the interband emission energy increase when the cylindrical quantum dot height or radius is decreased, and that the exciton binding energy, the oscillator strength and the radiative lifetime each as a function of structural parameters （height and radius） sensitively depend on the strong built-in electric field. The obtained results are useful for the design of some opto-photoelectronic devices.

关键词： quantum dot donor bound excitons oscillator strength