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Chinese Physics B 2017年第7期26卷 377-382页

作者： M A Ali M M Uddin M N i Khan F U Z Chowdhury s M Hoque s i Liba Department of Physics Chittagong University of Engineering and Technology (CUET) Materials science Division Atomic Energy Center

A series of Ni0.6-x/2Zn0.4-x/2snxFe2O4(x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.3)(NZsFO) ferrite composities have been synthesized from nano powders using a standard solid state reaction technique. The spinel cubic structure of the investigated samples has been confirmed by x-ray diffraction(XRD). The magnetic properties such as saturation magnetization(Ms),remanent magnetization(Mr), coercive field(Hc), and Bohr magneton(μ) are calculated from the hysteresis loops. The value of Msis found to decrease with increasing sn content in the samples. This change is successfully explained by the variation of A-B interaction strength due to sn substitution in different sites. The compositional stability and quality of the prepared ferrite composites have also been endorsed by the fairly constant initial permeability(μ’) over a wide range of frequency. The decreasing trend of μ’ with increasing sn content has been observed. Curie temperature TChas been found to increase with the increase in sn content. A wide spread frequency utility zone indicates that the NZsFO can be considered as a good candidate for use in broadband pulse transformers and wide band read-write heads for video recording. The composition of x = 0.05 shows unusual results and the possible reason is also mentioned with the established formalism.

关键词： magnetic properties saturation magnetization permeability Curie temperature

An　integral　Method　for　the　Measurement　of　Technological　Progress　and　Data　Envelopment　Analysis

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systems science and systems Engineering 1996年第1期6卷 75-86页

作者： WEi Quanling(institute of Operation Research Mathematics of EconomicsThe People’s Univ.of China,Beijing 100872,China)CHiANG Wen-Chyuan(Department of Quantitative Methods and mis College of Business,The Univ.of Tulsa,Tulsa OK 74104,UsA)

DEA method can be regarded as a non-parametric statistical estimating method which is applied to the determination of the frontier production *** Technological progress can be studied by the change of frontier production *** this paper, using the efficient frontier face obtained from DEA method,the new methoan integral method for estimating the speed of technological progress of enterprise group is *** integral method for estimating the speed of technonlogical progress of enterprise group in the case of an arbitray number of inputs for factor augmenting technological progress is *** assumption of the homogeneity of degree 1 for the production function is relaxed to the general case.A case study from application of Chinese agriculture demonstrates the usefulness of the method.

关键词： Technological Progress Data Envelopment Analysis Mathematical Programming

大厨用奥运村多余食物为里约贫民烹制美食（英文）

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大学英语 2016年第11期 29-30页

作者： Magdalena mis 佘建群

As athletes have warmed up for the Rio Olympics 2016,dozens of chefs are preparing for a different kind of challenge:feeding the Brazilian host city’s hungry with excess food from the Olympic *** Davic Hertz from Barzil and italian Massimo Bottura,aided by more than 40 colleagues from around the world,aim to turn surplus food from the village in Rio de

关键词：高校英语课外阅读阅读材料

Proposed graphene nanospaser

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Light(science & Applications) 2014年第1期3卷 141-146页

作者： Vadym Apalkov Mark i stockman Department of Physics and Astronomy Georgia State UniversityAtlantaGA 30303USA Faculty of Physics Ludwig Maximilian UniversityD-80539 MunichGermany Max Plank institute for Quantum Optics D-85748 GarchingGermany

We propose a novel nanospaser that operates in the mid-infrared region and utilizes a nanopatch of graphene as its plasmonic core and a quantum-well cascade as its gain *** design takes advantage of the low optical losses in graphene resulting from its high electron *** proposed quantum cascade graphene spaser generates optical fields with unprecedentedly high nanolocalization,which is characteristic of graphene *** spaser will be an efficient nanosource of intense and coherent hot-spot fields in the mid-infrared spectral region with potential widespread applications in mid-infrared nanoscopy,nanospectroscopy,nanolithography,and optoelectronic information processing.

关键词： graphene quantum cascade laser quantum well spaser

Organic carbon isotope and molecular fossil records of vegetation evolution in central Loess Plateau since 450 kyr

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science China Earth sciences 2016年第6期59卷 1206-1215页

作者： ZHOU Bin WALi Guzalnur Francien PETERsE Michael i BiRD Key Laboratory of surficial Geochemistry (Ministry of Education) School of Earth Sciences and Engineering Nanjing University Utrecht University Department of Earth Sciences College of science Technology and Engineering and Centre for Tropical Environmental and Sustainability Science James Cook University

significant uncertainties remain regarding the temporal evolution of natural vegetation during the Quaternary, and drivers of past vegetation change, on the Chinese Loess Plateau （CLP）. This study presents analyses of total organic carbon isotopic composition （TOC） and n-alkane ratios （C31/C27） from the Lingtai loess-palaeosol sequence on the central CLP over the last 450 kyr. The results demonstrate that the vegetation in this region comprised a mix of C3 and C4 plants of herb and woody growth-form. C3 plants dominated for most of the last 450 kyr, but this did not lead to extensive forest. C3 woody plants were more abundant in mis9 （s3 period） and mis5 （s 1 period） during warm and humid climate conditions. Herbs increased in the region since 130 kyr, possibly as a result of increased aridity. On the orbital timescales, there was a reduction of C3 herbal plants in mis 11 （$4） than in M1s 12 （L5）, and in Holocene than in the last glacial period. Our isotope and n-alkane proxy records are in agreement with Artemisia pollen changes in the region, which is/was the dominant species in this area and varying due to different heat and water conditions between glacial and interglacial periods. Though the climate in mis1 （sO） was similar to that in mis11 （s4）, a significant increase in woody plants during the Holocene suggests the impact of human activities and ecological effects of changes in fire activity.

关键词： Carbon isotopic composition Leaf wax lipids C3/C4 variations Late Quaternary vegetation change Glacial/interglacial cycles

A computational study on the optical shaping of gas targets via blast wave collisions for magnetic vortex acceleration

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High Power Laser science and Engineering 2022年第5期10卷 35-49页

作者： i.Tazes s.Passalidis E.Kaselouris i.Fitilis M.Bakarezos N.A.Papadogiannis M.Tatarakis V.Dimitriou institute of Plasma Physics and Lasers-iPPL Hellenic Mediterranean University Research CentreRethymnonGreece Department of Electronic Engineering Hellenic Mediterranean UniversityChaniaGreece CNRs Laboratoire de Chimie Physique-Matière et RayonnementSorbonne UniversitéParisFrance Department of Music Technology and Acoustics Hellenic Mediterranean UniversityRethymnonGreece

This research work emphasizes the capability of delivering optically shaped targets through the interaction of nanosecond laser pulses with high-density gas-jet profiles,and explores proton acceleration in the near-critical density regime via magnetic vortex acceleration(MVA).Multiple blast waves(BWs)are generated by laser pulses that compress the gas-jet into near-critical steep gradient slabs of a few micrometres *** alternatives for delivering the laser pulses into the gas target are explored to efficiently control the characteristics of the density *** shock front collisions of the generated BWs are computationally studied by 3D magnetohydrodynamic *** efficiency of the proposed target shaping method for MVA is demonstrated for TW-class lasers by a particle-in-cell simulation.

关键词： blast waves particle acceleration magnetic vortex acceleration MHD simulations PiC simulations

Ten years of spasers and plasmonic nanolasers

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Light(science & Applications) 2020年第1期9卷 1133-1153页

作者： shaimaa i.Azzam Alexander V.Kildishev Ren-Min Ma Cun-Zheng Ning Rupert Oulton Vladimir M.shalaev Mark i.stockman Jia-Lu Xu Xiang Zhang school of Electrical&Computer Engineering and Birck Nanotechnology Center Purdue UniversityWest LafayetteIN 47907USA Purdue Quantum science and Engineering institute Purdue UniversityWest LafayetteIN 47907USA state Key Lab for Mesoscopic Physics and school of Physics Peking UniversityBeijingChina Frontiers science Center for Nano-optoelectronics&Collaborative innovation Center of Quantum Matter BeijingChina Department of Electronic Engineering and international Center for Nano-Optoelectronics Tsinghua University100084 BeijingChina school of Electrical Computerand Energy EngineeringArizona State UniversityTempeAZ 85287USA The Blackett Laboratory Imperial College LondonSouth KensingtonLondon SW72AZUK Center for Nano-Optics(CeNO)and Department of Physics and Astronomy Georgia State UniversityAtlantaGA 30303USA Nanoscale science and Engineering Center University of CaliforniaBerkeleyBerkeleyCA 94720USA Faculties of sciences and Engineering University of Hong KongHong KongChina

Ten years ago,three teams experimentally demonstrated the first spasers,or plasmonic nanolasers,after the spaser concept was first proposed theoretically in *** overview of the significant progress achieved over the last 10 years is presented here,together with the original context of and motivations for this *** a general introduction,we first summarize the fundamental properties of spasers and discuss the major motivations that led to the first demonstrations of spasers and *** is followed by an overview of crucial technological progress,including lasing threshold reduction,dynamic modulation,room-temperature operation,electrical injection,the control and improvement of spasers,the array operation of spasers,and selected applications of single-particle *** prospects are presented in relation to several directions of development,including further miniaturization,the relationship with Bose-Einstein condensation,novel spaser-based interconnects,and other features of spasers and plasmonic lasers that have yet to be realized or challenges that are still to be overcome.

关键词： lasers overcome operation

Nutrition in soccer:A Brief Review of the issues and solutions

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Journal of science in sport and Exercise 2019年第1期1卷 3-12页

作者： D.Caruana Bonnici M.Greig i.Akubat s.A.sparks D.Bentley L.R.Mc Naughton Department of sport and Physical Activity Edge Hill UniversityOrmskirk L394QPUK Faculty of Arts Society and Professional StudiesNewman UniversityBirmingham B323NTUK College of Nursing and Health science Flinders UniversityAdelaideSA 5001Australia

This review examines the issues surrounding soccer nutrition,including the nature of the game,training,and how nutrition can play a significant role in improving player performance and *** soccer match-play,a total distance covered of up to 13 km is characterised by an acyclical and intermittent activity *** aerobic system is highly taxed,with average heart rates of~85%of maximal values,and the finite muscle glycogen stores represent a key aspect of the interface between training,performance and nutritional *** with high CHO content can optimise muscle glycogen,reduce net glycogen depletion,delay the onset of fatigue,and improve soccer *** is more common,however,for players to consume an excessive amount of protein in their daily diet perpetuating the popular belief that additional protein increases strength and enhances *** comprehensive recommendations suggest that soccer players should consume a high CHO diet from nutrient-rich complex CHO food sources that ranges from a minimum of 7 to 10 g/kg BM and up to 12 g/kg BM on match or heavy training ***,players often have a low energy intake,which can lead to nega-tive energy balance,especially at times of schedule *** many cases,soccer players often consume diets that are not very different from those of the general ***,despite a clear understanding of the physiological demands of soccer,and the association between nutritional preparation and performance,the dietary habits of soccer players are often characterised by a lack of education and mis-informed sporting *** review discusses the potential barriers and various nutritional phases that need to be considered for training,pre,on the day of,and post-match to enable players and coaches to be more aware of the need to achieve more optimal macronutrient nutrition.

关键词： Football Carbohydrate Protein Performance Fluids

Preferences for pre-exposure prophylaxis among U.s. military men who have sex with men:results of an adaptive choice based conjoint analysis study

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Military Medical Research 2022年第2期9卷 141-151页

作者： Joséi.Gutierrez Alex Dubov Frederick L.Altice David Vlahov Yale school of Nursing 400 West Campus DriveOrangeCT 06477USA Philip R.Lee institute for Health Policy studies University of CaliforniaSan Francisco3333 California StSan FranciscoCA 94118USA Loma Linda University Griggs Hall 11065Loma LindaCA 92350USA Yale school of Medicine Section of Infectious Diseases135 College StreetSuite 323New HavenCT 06510USA Department of Epidemiology-Microbial Diseases Yale School of Public Health60 College StNew HavenCT 06510USA

Background: Pre-exposure prophylaxis(PrEP) prevents human immunodeficiency virus(HiV) infection, but its use remains low among U.s. military men who have sex with men(MsM), likely due to mis-matching with personal preferences. We conducted a study to characterize preferences to PrEP measures within this ***: HiV-negative military MsM were recruited through a closed, Lesbian, Gay, Bisexual, and Transgendered(LGBT) military social media group. The survey was anonymous, and consisted of five experimentally varied attributes in service delivery: dosing method, provider type, visit location, lab work evaluation location, and dispensing *** importance and part-worth utility scores were generated using hierarchical bayes(HB) estimation, and the randomized first choice model was used to examine participation interest across eight possible PrEP program ***: A total of 429 participants completed the survey. Among the eight scenarios with varying attributes, the most preferred scenario featured a daily tablet, PrEP injection or implant, along with a military provider, smartphone/telehealth visit, and on-base locations for lab evaluation and medication pick-up. The results also emphasized the importance for providers to be familiar with PrEP prescription knowledge, and to provide interactions sensitive to sexual identity and mental ***: A PrEP program consisting of daily tablet is preferred in military healthcare settings is preferred. Longacting implants and injections are also desired.

关键词： Conjoint analysis Pre-exposure prophylaxis Preference Decision science Human immunodeficiency virus Military health infectious disease

Deployment of wireless sensor network in dispersed renewable energy sources for increasing efficiency of power distribution networks

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Journal of Modern Power systems and Clean Energy 2015年第4期3卷 610-618页

作者： Theodoros A.TsiFTsis Paschalis C.sOFOTAsiOs Nick PAPANiKOLAOU Michael i.LOUPis Technological Educational institute(T.E.i.)of Central Greece 35100 LamiaGreece Tampere University of Technology 33101 TampereFinland Democritus University of Thrace Kimmeria67100 XanthiGreece

in this work,a novel performance analysis method for evaluating the robustness of emerging power distribution networks(PDNs),which involve deployable renewable energy sources,is *** is realized with the aid of the outage probability(OP)criterion in the context of cooperative communications,which is widely considered in modern wireless communication *** main usefulness of this method is that it allows the involved components to communicate to each-other by means of a robust and flexible wireless sensor network *** this context,any conventional medium voltage(MV)bus of the PDN is represented as a wireless relay node where data signals gathered from each MV bus can be forwarded reliably to a control station for the subsequent *** received signals at wireless nodes are decoded and then forwarded to ensure minimal errors and maximal robustness at the receiving *** considered OP analysis denotes the probability that the power of a received information signal drops below a pre-defined threshold which satisfies the acceptable Quality of service requirements of a reliable signal *** this end,simple closed-form expressions are proposed for the OP of a regenerative cooperative-based PDN in the presence of various multipath fading effects,which degrade information signals during wireless *** offered results are rather simple and provide meaningful insights for the design and deployment of smart grid systems.

关键词： smart grid Cooperative communications(CCs) Power distribution network(PDN) Outage probability Renewable energy source(REs) Wireless sensor network(WsN)