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Chinese Journal of Polymer Science 1998年第3期16卷 261-267页

作者： GUILLET james Department of Chemistry University of Toronto Toronto M5S 3H6 Canada

Polymers of 1- and 2-vinylnaphthalene containing more than about 50 mol% sulfonic acid groups dissolve in water to form 'hypercoiled' conformations which have many of the properties of micelles. hydrophobic molecules such as anthracene and perylene are selectively absorbed in these pseudo micellar structures, and their fluorescence emission is sensitized by energy transfer from the surrounding naphthalene chromophores. When irradiated with UV light in the presence of oxygen, the emission of perylene rapidly decreases. It is proposed that this is due to reaction of singlet oxygen with the perylene trapped in the hypercoiled polymer. (Author abstract) 3 Refs.

关键词： Sulfonated vinyl naphthalene polymers Transport of excitation energy Anthracene Perylene Tripping

Usability Assessment of Steering Wheel Control Interfaces in Motorsport

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Automotive Innovation 2020年第1期3卷 42-52页

作者： james W.h.Brown Neville A.Stanton Kirsten M.A.Revell University of Southampton SouthamptonUK

In order to assess the usability of steering wheel control interfaces in motorsport,it is necessary to employ a set of appropriate *** method selection process first involves identifying the relevant motorsport-based usability *** unique factors associated with context of use in motorsport are then *** are employed to synthesize a set of key performance indicators(KPIs)that require specific *** first KPI relates to error rates;these should be minimized,particularly under high cognitive load on the *** second KPI involves task times;these should be minimized not just to reduce distraction,but also to improve competitive *** third KPI states that usability should be optimized to minimize visual *** fourth KPI advocates the minimizing of interface task load to reduce the effect on the primary *** final KPI states that interface functionality should be easy to learn and *** KPIs provide clear goals to guide the identification of the most appropriate methods for each aspect of *** categories are devised and sets of appropriate methods selected based on the *** then combine into a toolset with an associated application process with the overall goal of providing a means by which motorsport interfaces may be both analysed and improved.

关键词： Usability Motorsport Steering wheel Analysis Assessment

Multiple radial phosphorus segregations in GaAsP core-shell nanowires

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Nano Research 2021年第1期14卷 157-164页

作者： h.Aruni Fonseka Yunyan Zhang james A.Gott Richard Beanland huiyun Liu Ana M.Sanchez Department of Physics University of WarwickCoventry CV47ALUK Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK

highly faceted geometries such as nanowires are prone toform self-formed features,especially those that are driven by *** these features is important in preventing their formation,understanding their effects on nanowire properties,or engineering them for *** elemental segregation lines that run along the radii of the hexagonal cross-section have been a common observation in alloy semiconductor ***,in GaAsP nanowires,two additional P rich bands are formed on either side of the primary band,resulting in a total of three segregation bands in the vicinity of three of the alternating *** bands are less intense than the primary band and their formation can be attributed to the inclined nanofacets that form in the vicinity of the *** formation of the secondary bands requires a higher composition of P in the shell,and to be grown under conditions that increase the diffusivity difference between As and ***,it is observed that the primary band can split into two narrow and parallel *** can take place in all six radii,making the cross sections to have up to a maximum of 18 radial segregation *** controlled growth,these features could be exploited to assemble multiple different quantum structures in a new dimension(circumferential direction)within nanowires.

关键词： compound semiconductor alloys radial segregations three-fold symmetry surface chemical potential

Tree Population Dynamics of Three Altitudinal Vegetation Communities on Mount Cameroon(1989-2004)

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Journal of Mountain Science 2011年第4期8卷 495-504页

作者： Philip F.FORBOSEh Terry C.h.SUNDERLAND james A.COMISKEY Michael BALINGA Plan Cameroon P O Box 25236 MessaYaoundéCameroon Centre for International Forestry Research(CIFOR) Inventory and Monitoring Program National Park Service120 Chatham Lane Smithsonian Institution S.Dillon Ripley Center1100 JeffersonDrive SW Washington DC 20560USA Center for International Forestry Research(CIFOR)

Changes in permanent sample plots in the lowland,submontane and montane forests on Mount Cameroon(4,095 m above sea level),an active volcano,are described for 15 years from 1989 to *** the study period,the stocking level of trees with a diameter at breast height(DBh) ≥ 10 cm in the three forests were lower than in pan-tropical stands suggesting a significant impact of volcanic and human-related activities on the vegetation communities on the *** mortality rates in the submontane and montane forests were consistent with those reported for comparable altitudinal ranges in the Blue Mountains of *** annual mortality rate was higher in the lowland forest than other lowland sites *** between recruitment and mortality rates was large suggesting that the three vegetation communities have not reached their *** seven-year difference in half-life of large trees(with a DBh ≥ 50 cm) in the submontane and montane forests suggests an altitudinal effect on turnover of larger trees that in turn contributes to the frequent small stature of high altitude *** was little evidence of an altitudinal effect on species turnover and growth *** finding supports generalizations about the zero effect of growth on the stature of high altitude *** forest dynamics is crucially important in the management of tropical montane environmentsand in this instance particularly so given the recent creation of the Mount Cameroon National Park.

关键词：植被群落高海拔喀麦隆活火山种群动态山地森林树木胸径热带山地

On the electrical conductivity of alginate hydrogels

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Regenerative Biomaterials 2018年第5期5卷 293-301页

作者： Georgia Kaklamani Diana Kazaryan james Bowen Fabrice Iacovella Spiros h.Anastasiadis George Deligeorgis Institute of Electronic Structure&Laser Foundation for Research&Technology HellasP.O.Box 138571110 HeraklionCreteGreece School of Engineering and Innovation The Open UniversityMilton Keynes MK76AAUK Department of Chemistry University of CreteP.O.Box 220871003 HeraklionCreteGreece

hydrogels have been extensively used in the field of biomedical applications,offering customizable natural,synthetic or hybrid materials,particularly relevant in the field of tissue *** the bioelectronics discipline,hydrogels are promising mainly as sensing platforms with or without encapsulated cells,showing great potential in healthcare and ***,to date there is little data in the literature which characterizes the electrical properties of tissue engineering materials which are relevant to *** this work,we present electrical characterization of alginate hydrogels,a natural polysaccharide,using a four-probe method similar to electrical impedance *** acquired conductance data show distinct frequency-dependent features that change as a function of alginate and crosslinker concentration reflecting ion kinetics inside the measured ***,the presence of NIh 3T3 fibroblasts encapsulated in the hydrogels matrix was found to alter the artificial tissue’s electrical *** method used provides valuable insight to the frequency-dependent electrical response of the resulting *** is hoped that the outcome of this research will be of use in the development of cell/electronic interfaces,possibly toward diagnostic biosensors and therapeutic bioelectronics.

关键词： alginate bioelectronics conductivity hydrogel polysaccharide resistance fibroblasts

Control of Rhyzopertha dominica in stored rough rice through a combination of diatomaceous earth and varietal resistance

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Insect Science 2008年第5期15卷 455-460页

作者： Yaowaluk Chanbang Frank h. Arthur Gerald E. Wilde james E. Throne Chiang Mai University Chiang Mai Thailand USDA-ARS Grain Marketing and Production Research Center Manhattan KS USA Department of Entomology Kansas State University Manhattan KS USA

Adults ofRhyzopertha dominica （F.）, the lesser grain borer, were exposed on four varieties of rough rice with Dobie indices of susceptibility of 1.1 to 1.1 （low）, and four varieties with Dobie indices of susceptibility of 3.4 to 3.8 （high）. The varieties with low and high Dobie indices were classified as resistant and susceptible, respectively, to R. dominica. The purpose of the study was to evaluate control of R. dominica through the use of diatomaceous earth （DE） in combination with rice varieties that were either susceptible or resistant to R. dominica. The rice was treated with varying rates of the commercial DE Insecto, up to a maximum of 1 000 mg DE/kg of rice. Adult mortality at each application rate of DE was generally greater on three of four resistant varieties compared to three of four susceptible varieties. Progeny production from the parental generation exposed on the rice was also greater in 3 of the 4 resistant varieties compared to 3 of the 4 susceptible varieties at DE rates of 500 mg/kg or more. Progeny production in rice treated with a maximum rate of 1 000 mg/kg DE ranged from 7-44 adults on the resistant varieties compared to 75-155 adults on the susceptible varieties. At DE rates of 500, 750, and 1 000 mg/kg, the percentage of insect-damaged kernels （IDK） was also greater in 3/4 resistant varieties than in the susceptible varieties. Results show combining the use of DE with varietal resistance of rough rice to R. dominica could be used to limit populations of this insect in stored rice and help prevent economic damage.

关键词： diatomaceous earth DE host plant resistance integrated control rice

Dynamics of self-hybridized exciton–polaritons in 2D halide perovskites

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Light(Science & Applications) 2024年第1期13卷 13-22页

作者： Surendra B.Anantharaman Jason Lynch Christopher E.Stevens Christopher Munley Chentao Li Jin hou hao Zhang Andrew Torma Thomas Darlington Francis Coen Kevin Li Arka Majumdar Pjames Schuck Aditya Mohite hayk harutyunyan Joshua R.hendrickson Deep Jariwala Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA KBR Inc. BeavercreekOH45431USA Air Force Research Laboratory Sensors DirectorateWright-Patterson Air Force BaseOH45433USA Department of Physics University of WashingtonSeattleWA98195USA Department of Physics Emory UniversityAtlantaGA30322USA Department of Chemical and Biomolecular Engineering Rice UniversityHoustonTX77005USA Department of Materials Science and Nanoengineering Rice UniversityHoustonTX77005USA Applied Physics Program Smalley‐Curl InstituteRice UniversityHoustonTX77005USA Department of Mechanical Engineering Columbia UniversityNew YorkNY10027USA Department of Electrical and Computer Engineering University of WashingtonSeattleWA98195USA

Excitons,bound electron–hole pairs,in two-dimensional hybrid organic inorganic perovskites(2D hOIPs)are capable of forming hybrid light-matter states known as exciton-polaritons(E–Ps)when the excitonic medium is confined in an optical *** the case of 2D hOIPs,they can self-hybridize into E–Ps at specific thicknesses of the hOIP crystals that form a resonant optical cavity with the ***,the fundamental properties of these self-hybridized E–Ps in 2D hOIPs,including their role in ultrafast energy and/or charge transfer at interfaces,remain ***,we demonstrate that>0.5µm thick 2D hOIP crystals on Au substrates are capable of supporting multiple-orders of self-hybridized E–P *** E–Ps have high Q factors(>100)and modulate the optical dispersion for the crystal to enhance sub-gap absorption and *** varying excitation energy and ultrafast measurements,we also confirm energy transfer from higher energy E–Ps to lower energy E–***,we also demonstrate that E–Ps are capable of charge transport and transfer at *** findings provide new insights into charge and energy transfer in E–Ps opening new opportunities towards their manipulation for polaritonic devices.

关键词： charge polar excitation

highly efficient GaAs solar cells by limiting light emission angle

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Light(Science & Applications) 2013年第1期2卷 236-241页

作者： Emily D Kosten Jackson h Atwater james Parsons Albert Polman harry A Atwater Thomas J.Watson Laboratories of Applied Physics California Institute of TechnologyPasadenaCA 91125 USA Center for Nanophotonics FOM-Institute AMOLFScience Park 1041098XG AmsterdamThe Netherlands

In a conventional flat plate solar cell under direct sunlight,light is received from the solar disk,but is re-emitted *** isotropic emission corresponds to a significant entropy increase in the solar cell,with a corresponding drop in ***,using a detailed balance model,we show that limiting the emission angle of a high-quality GaAs solar cell is a feasible route to achieving power conversion efficiencies above 38%with a single *** highest efficiencies are predicted for a thin,light trapping cell with an ideal back reflector,though the scheme is robust to a non-ideal back *** with a conventional planar cell geometry illustrates that limiting emission angle in a light trapping geometry not only allows for much thinner cells,but also for significantly higher overall efficiencies with an excellent rear ***,we present ray-tracing and detailed balance analysis of two angular coupler designs,show that significant efficiency improvements are possible with these couplers,and demonstrate initial fabrication of one coupler design.

关键词： detailed balance GaAs solar cell light trapping photovoltaics two photon lithography

Atomically Dispersed Fe-Co Bimetallic Catalysts for the Promoted Electroreduction of Carbon Dioxide

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Nano-Micro Letters 2022年第2期14卷 79-93页

作者： Zhangsen Chen Gaixia Zhang Yuren Wen Ning Chen Weifeng Chen Tom Regier james Dynes Yi Zheng Shuhui Sun Institut National de la Recherche Scientifique-Énergie Matériaux et Télécommunications VarennesQC J3X 1P7Canada School of Materials Science and Engineering University of Science and Technology100083 BeijingPeople’s Republic of China Canadian Light Source University of SaskatchewanSaskatoonSK S7N 2V3Canada Research Institute of Photocatalysis State Key Laboratory of Photocatalysis on Energy and EnvironmentFuzhou UniversityFuzhou 350116People’s Republic of China

The electroreduction reaction of CO_(2)(ECO_(2)RR)requires high-performance catalysts to convert CO_(2)into useful *** metal-based atomically dispersed catalysts are promising for the high selectivity and activity in ECO_(2)*** work presents a series of atomically dispersed Co,Fe bimetallic catalysts by carbonizing the Fe-introduced Co-zeolitic-imidazolate-framework(C-Fe-Co-ZIF)for the syngas generation from ECO_(2)*** synergistic effect of the bimetallic catalyst promotes CO *** to the pure C-Co-ZiF,C-Fe-Co-ZIF facilitates CO production with a CO Faradaic efficiency(FE)boost of 10%,with optimal FE_(CO)of 51.9%,FE_(h_(2))of 42.4%at-0.55 V,and CO current density of 8.0 mA cm^(-2)at-0.7 V versus reversible hydrogen electrode(RhE).The h_(2)/CO ratio is tunable from 0.8 to 4.2 in a wide potential window of-0.35 to-0.8 V versus *** total FE_(CO+h_(2))maintains as high as 93%over 10 *** proper adding amount of Fe could increase the number of active sites and create mild distortions for the nanoscopic environments of Co and Fe,which is essential for the enhancement of the CO production in ECO_(2)*** positive impacts of Cu-Co and Ni-Co bimetallic catalysts demonstrate the versatility and potential application of the bimetallic strategy for ECO_(2)RR.

关键词： CO_(2)reduction Electrocatalysis Syngas production Cobalt Iron Bimetallic catalysts

Diversity of Insect Flower Visitors on Macadamia within a Monoculture Orchard in Murang’a County, Central Kenya

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Advances in Entomology 2023年第4期11卷 239-255页

作者： Nicholas I. Njue james W. Muthomi George N. Chemining’wa John h. Nderitu Josiah Achieng james J. Odanga Department of Plant Science and Crop Protection University of Nairobi Nairobi Kenya Invertebrate Zoology Section National Museums of Kenya Nairobi Kenya

Macadamia is cultivated for its nutritious edible kernel. In Kenya, the crop is predominantly grown by smallholder farmers mainly for export markets. Macadamia trees also enhance agro-forestry conservation, in the East African farmlands, by providing habitat and floral resources to beneficial arthropods such as insect pollinators. Allogamy of macadamia flowers is largely dependent on insects that pollinate and consequently influence the nut set, retention and yield. however, there is limited information on macadamia insect flower visitors in Kenya. This article assessed the diversity of insects that forage flowers of macadamia crop, and further evaluated their temporal distribution, in Murang’a county, central Kenya. Insect flower visitors were sampled weekly using a butterfly net for twelve consecutive months, from January 2021 to December 2021. Sixty-one insect species were recorded foraging macadamia flowers in Murang’a county, central Kenya. There was a statistical difference in the Simpson diversity index among weather seasons, dry, long rain, cold and short rain (p Apis mellifera), a key pollinator species, being the most abundant flower visitor. This study provides strong baseline information, to scientists and farmers, on probable macadamia pollinator species, in central Kenya. .

关键词： Macadamia Flowers Insect Diversity Kenya