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H在a-SiN_x:H光电导衰减中的作用

真空科学与技术 1997年第1期17卷 7-11页

作者：张仕国 d.e.brodie 浙江大学硅材料国家重点实验室杭州310027 滑铁卢大学物理系

在真空蒸发硅的同时，分别用N离子和NH3离子轰击生长表面，获得具有不同H和N含量的a－SiNx和a－SiNx：H薄膜。对于这些薄膜，只要它们具有光电导特性，就可以观察到光电导衰减现象。实验分析表明，H在光电导衰减中不起直接作用，而是通... 详细信息

在真空蒸发硅的同时，分别用N离子和NH3离子轰击生长表面，获得具有不同H和N含量的a－SiNx和a－SiNx：H薄膜。对于这些薄膜，只要它们具有光电导特性，就可以观察到光电导衰减现象。实验分析表明，H在光电导衰减中不起直接作用，而是通过增大a－SiNx：H的光学能隙，使陷阱更为有效；以及减少Si≡Si－复合中心，从而有可能提高非平衡自由或流子密度和增强电荷被陷的速率，而间接地增强光电导衰减。

关键词：非晶氮化硅光电导衰减真空蒸发薄膜

Performance analysis of deep borehole heat exchangers for decarbonization of heating systems

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deep Underground Science and engineering 2024年第3期3卷 349-357页

作者： Andreas e.d.Lund department of electrical engineering and Automation Aalto UniversityEspooFinland

Meeting the climate change mitigation targets will require a substantial shift from fossil to clean fuels in the heating *** pumps with deep borehole exchangers are a promising solution to reduce *** the thermal behavior of deep borehole exchangers(dBHes)ranging from 1 to 2 km was analyzed for various heat flow profiles.A strong correlation between thermal energy extraction and power output from dBHes was found,also influenced by the heating profile *** operating time over the year typically resulted in higher energy production,while shorter one yielded higher average thermal power output,highlighting the importance of the choice of heating strategy and system design for optimal performance of *** breaks in operation for regenerating the borehole,for example,with waste heat,proved to be favorable for the performance yielding an overall heat output close to the same as with continuous extraction of *** results demonstrate the usefulness of deep boreholes for dense urban areas with less available *** the heat production from a single dBHe in Finnish conditions ranges from half up to even a few GWh a year,the technology is best suitable for larger heat loads.

关键词： clean energy deep borehole exchangers energy transition geothermal heat ground-coupled heat pump

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Converting TRex-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang d.M.Gillies e.Spanswick e.F.donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TRex-RGB data *** methodology established in this study will also be applicable to the upcoming SMILe ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TRex RGB green-line aurora auroral transport model

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： d A Baghdasaryan V A Harutynyan e M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.James J.e.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.V.Jolos e.A.Kolganova d.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

The 2024 Compendium of Physical Activities and its expansion

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Journal of Sport and Health Science 2024年第1期13卷 1-2,F0003页

作者： Stephen d.Herrmann erik A.Willis Barbara e.Ainsworth Kansas Center for Metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA School of exercise and Health Shanghai University of SportShanghai 200438China

First developed 30 years ago,the Compendium of Physical Activities(Compendium)was created to provide a standardized way of measuring and classifying specific physical activities(PAs),allowing researchers and health professionals to assess the energy expenditure and health benefits associated with different PA.1Since its inception,the Compendium has been widely utilized and recognized as a fundamental PA and health resource.

关键词： has utilized classify

2024 Wheelchair Compendium of Physical Activities:An update of activity codes and energy expenditure values

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Journal of Sport and Health Science 2024年第1期13卷 18-23页

作者： Scott A.Conger Stephen d.Herrmann erik A.Willis Tom e.Nightingale Joseph R.Sherman Barbara e.Ainsworth department of Kinesiology Boise State UniversityBoiseID 83725USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA School of Sport Exercise and Rehabilitation SciencesUniversity of BirminghamBirmingham AL B152TTUK Centre for Trauma Sciences Research University of BirminghamEdgbastonBirmingham AL B152TTUK College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of exercise and Health Shanghai University of SportShanghai 200438China

Purpose:This paper presents an update of the 2011 Wheelchair Compendium of Physical Activities designed for wheelchair users and is referred to as the 2024 Wheelchair *** Wheelchair Compendium aims to curate existing knowledge of the energy expenditure for wheelchair physical activities(PAs).Methods:A systematic review of the published energy expenditure of PA for wheelchair users was completed between 2011 and May *** added these data to the 2011 Wheelchair Compendium data that was compiled previously in a systematic review through ***:A total of 47 studies were included,and 124 different wheelchair PA reported energy expenditure values ranging from 0.8 metabolic equivalents for wheelchair users(filing papers,light effort)to 11.8 metabolic equivalents for wheelchair users(Nordic sit skiing).Conclusion:In introducing the updated 2024 Wheelchair Compendium,we hope to bridge the resource gap and challenge the prevailing narratives that inadvertently exclude wheelchair users from physical fitness and health PAs.

关键词： disability exercise MeT Mobility

Malargüe Site Remediation:A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年第10期58卷 2088-2094页

作者： BARARI e díAZ J G GIOMIA KeMPF R A National Atomic energy Commission Av.Del Libertador 8250Ciudad Autónoma de Buenos AiresC1429BNPArgentina

Comisión Nacional de energía Atómica (CNeA) has the responsibility for restoring uranium mining facilities once the operations have ***,within its environmental Program and in compliance with its legal responsibilities,decides to implement a restoration project for all sites related to the mining and processing of uranium *** Malargüe Site is located within the Province of Mendoza in the city of Malargü*** is the first site to successfully complete its *** activities consist of relocation of tailings to an engineering *** tailings management(encapsulation) and rehabilitation of the area was finished in June *** remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for *** objective of the encapsulation of the mineral tails is to isolate them from the environment,also proceeding with the decontamination and rehabilitation of the area (landscaping,post-closure monitoring and 20 years monitoring period).encapsulation consisted of the construction of a containment cell for the mine tailings,to isolate them and prevent pollutants from entering the environment through the transfer *** clean the impacted areas,the soil was removed,it was incorporated into the encapsulation,and the filling was carried out with natural soils from the *** prevents radon transfer to the environment,as ^(222)Ra is an alpha emitter with a half-life of four days,which produces its own radioactive *** progeny are solids,and when a ^(222)Ra nucleus emits an alpha particle into the air,the resulting ^(218)Po nucleus,momentarily electrically charged,adheres to any dust *** prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon *** tasks mentioned make it possible to decrease radon emanation,reduce radiological risks to the public and pre

关键词： remediation radionuclide transfer tailings encapsulation solution sustainable