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The Synthesis of a Novel Lignan

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Chinese Chemical Letters 2000年第11期11卷 971-974页

作者： Qi X.X. Chang j.b. Guo R.Y. Chen R.F. Chem. Dept. of Zhengzhou Univeristy Zhengzhou 450052 China Henan Institute of Chemistry Henan Academy Sciences Zhengzhou 450002 China

A short convenient synthesis of a novel lignan, 2-(3′,4′,5′-trimethyoxyphenyl)-1,3-dimethyl-6,7,8-trimethoxy- naphthalene has been accomplished by the condensation of key intermediates, 3,4,5-trimethoxybenzyl methy... 详细信息

关键词： UV Kbr IR The Synthesis of a Novel Lignan EtOH

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang Z.Yang S.Y.Yang Z.H.Dai Y.j.Liu j.H.Liao G.Y.Zhong Z.j.Xie Y.P.Fang S.S.Zhang Key Laboratory for biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

A Novel Fast Intra Prediction Algorithm applied in H.264/AVC

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A Novel Fast Intra Prediction Algorithm applied in H.264/AVC

Storylines of family medicine Ⅸ:people and places—diverse populations and locations of care

2006 8th International Conference on Signal Processing

作者： Song,j.b. Li,b. Li,W. jiang,L. Digital Media Laboratory School of Computer Science and EngineeringBeihang University

ISBN: (纸本)0780397371;9780780397378

＜正＞Intra prediction applied in H.264/AVC improves compression efficiency of I frame *** the full search algorithm is of high computational expense,which conflicts with some real time application and embedded systems with limited calculation *** order to promote prediction speed,a fast intra prediction algorithm is proposed in this paper which selects appropriate prediction block size based on complexity of the I frame,uses an annular sliding window to select prediction mode dynamically and defines a simple block match *** results show that it is so practical and valid that the match speed has been doubled while the quality of reconstruction I-frame is decreased only slightly.

关键词： video coding intra prediction block size annular slide window bMR

来源： cnki会议评论

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Family Medicine and Community Health 2024年第S3期12卷 79-88页

作者： William b Ventres Leslie A Stone Emad R Abou-Arab julio Meza David S buck jerome W Crowder jennifer Y C Edgoose Alexander brown Ellen j Plumb Amber K Norris jay j Allen Lauren E Giammar john E Wood Scott M Dickson G Austin brown Family and Preventive Medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA Family Medicine University of Michigan Medical SchoolAnn ArborMichiganUSA Family Medicine University of California Los AngelesDavid Geffen School of MedicineLos AngelesCaliforniaUSA Community Medicine University of HoustonTilman J Fertitta Family College of MedicineHoustonTexasUSA Social and behavioral Sciences University of HoustonTilman J Fertitta Family College of MedicineHoustonTexasUSA Family Medicine and Community Health University of Wisconsin-Madison School of Medicine and Public HealthMadisonWisconsinUSA NH Dartmouth Family Medicine Residency ConcordNew HampshireUSA San Francisco VA Medical Center San FranciscoCaliforniaUSA Duluth Family Medicine Residency Program University of Minnesota Medical School Duluth CampusDuluthMinnesotaUSA UAMS Northeast Regional Campus Family Medicine Residency Program JonesboroArkansasUSA Cascades East Family Medicine Residency Program Oregon Health&Science University School of MedicineKlamath FallsOregonUSA

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅸ:people and places—diverse populations and locations of care’,authors address the following themes:‘LGbTQIA+health in family medicine’,‘A family medicine approach to substance use disorders’,‘Shameless medicine for people experiencing homelessness’,“Difficult”encounters—finding the person behind the patient’,‘Attending to patients with medically unexplained symptoms’,‘Making house calls and home visits’,‘Family physicians in the procedure room’,‘Robust rural family medicine’and‘Full-spectrum family medicine’.May readers appreciate the breadth of family medicine in these essays.

关键词： illustration family dimensions

Seasonal Abundance and Diversity of birds of Prey and Owls in Al Wathba Wetland Reserve in Abu Dhabi, UAE

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Open journal of Ecology 2024年第3期14卷 228-244页

作者： Shakeel Ahmed Salim jáved Shahid b. Khan Eissa Al Hammadi Abdullah Al Hammadi Nouf Sameer Alqadi Environment Agency-Abu Dhabi Abu Dhabi United Arab Emirates

Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from january 1995 to December 2022. both diurnal and occasionally nocturnal surveys were undertaken to record the migratory raptors and owls in the Wetland Reserve. During the study, a total of 1282 regular monitoring visits were undertaken and 27 species of diurnal raptors and owls representing five families and three orders were detected. These represent 57% of the total species of birds of prey recorded in the UAE. Overall, 63% of all the species that we observed were Accipitriformes followed by 26% Falconiformes and 11% Strigiformes. We found that changes in mean daily temperature have a positive effect on raptor species diversity and abundance in the Wetland Reserve. The species encounter rate was higher in low temperature as compared to high temperature and overall regression equation was statistically significant F (4, 1126) = 8.49), p = 0.00). However, the numbers of raptors did not vary significantly across the years (p = 0.51). Western Marsh-harrier (Circus aeruginosus) and Greater Spotted Eagle (Clanga clanga) were recorded to be the most abundant species in the wetland reserve followed by Common Kestrel (Falco tinnunculus). However, the encounter rate of globally threatened Greater Spotted Eagle was detected to have significantly decreased since 2016. Moreover, 63% of the species detected were uncommon and rarely recorded such as 1) Saker Falcon 2) Lanner Falcon 3) Long-eared Owl & Merlin, which were the rare records from the wetland reserve. Furthermore, 27 years of regular monitoring in the wetland have yielded diverse diurnal raptors and owl fauna (H) = 0.83, (E) = 1.43 (Shannon Diversity Index). The results demonstrate that long-term monitoring surveys in arid environments are essential to determine the trends in the raptor populations and to document rare and globally

关键词： Wetland Reserve Raptors Abundance Diversity Abu Dhabi Inland Wetland AWWR Greater Spotted Eagle

Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki biswas Nicola j.Wagner Ofentse M.Moroeng DSI-NRF CIMERA/PPM Research Group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous b-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+Mn)and(Fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： Macerals Coal facies Geochemical-indices Hydrothermal Madzaringwe formation Soutpansberg Coalfield

Attitude control of multi-spacecraft systems on SO(3)with stochastic links failure

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Chinese journal of Aeronautics 2024年第3期37卷 320-331页

作者： KANG Zeyu SHEN Qiang WU Shufan Chris j.DAMAREN MU Zhongcheng School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Institute for Aerospace Studies University of TorontoTorontoOntario M3H 5T6Canada

In this paper,for Multi-Spacecraft System(MSS)with a directed communication topology link and a static virtual leader,a controller is proposed to realize attitude consensus and attitude stabilization with stochastic links failure and actuator ***,an MSS attitude error model suitable for a directed topology link and with a static virtual leader based on SO(3)is derived,which considers that the attitude error on SO(3)cannot be defined based on algebraic ***,we design a controller to realize the MSS on SO(3)with attitude consensus and attitude stabilization under stochastic links failure and actuator ***,the simulation results of a multi-spacecraft system with stochastic links failure and a static virtual leader spacecraft are demonstrated to illustrate the efficiency of the attitude controller.

关键词： Multi-spacecraft systems Attitude consensus Attitude stabilization Stochastic links failure Super-martingale convergence

Dissection of a rapidly evolving wheat resistance gene cluster by long-read genome sequencing accelerated the cloning of Pm69

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Plant Communications 2024年第1期5卷 69-83页

作者： Yinghui Li Zhen-Zhen Wei Hanan Sela Liubov Govta Valentyna Klymiuk Raj.b.Roychowdhury Harmeet Singh Chawla jennifer Ens Krystalee Wiebe Valeria bocharova Roi ben-David Prerna b.Pawar Yuqi Zhang Samidha jaiwar Istvan Molnar jaroslav Dolezel Gitta Coaker Curtis j.Pozniak Tzion Fahima Institute of Evolution University of HaifaMt.CarmelHaifa 3498838Israel The Department of Evolutionary and Environmental biology University of HaifaMt.CarmelHaifa 3498838Israel The Institute of Plant Protection Sichuan Academy of Agricultural SciencesChengdu 610066China Crop Development Centre and Department of Plant Sciences University of Saskatchewan51 Campus DriveSaskatoonSK S7N 5A8Canada Department of Vegetables and Field Crops Institute of Plant SciencesAgricultural Research Organization(ARO)–Volcani CenterRishon Lezion 7505101Israel Department of Crop Genomics and bioinformatics China Agricultural UniversityBeijing 100094China Institute of Experimental botany of the Czech Academy of Sciences Centre of the Region Hana´for Biotechnological and Agricultural ResearchSlechtitelu 3177900 OlomoucCzech Republic Plant Pathology Department University of CaliforniaDavisDavisCA 95616USA Present address:Department of Plant Science University of ManitobaWinnipegMB R3T 2N2Canada Present address:Agricultural Institute Centre for Agricultural ResearchELKHMartonvasar 2462Hungary

Gene cloning in repeat-rich polyploid genomes remains ***,we describe a strategy for overcoming major bottlenecks in cloning of the powdery mildew resistance gene(R-gene)Pm69 derived from tetraploid wild emmer wheat.A conventional positional cloning approach was not effective owing to suppressed *** sorting was compromised by insufficient purity.A Pm69 physical map,constructed by assembling Oxford Nanopore Technology(ONT)long-read genome sequences,revealed a rapidly evolving nucleotide-binding leucine-rich repeat(NLR)R-gene cluster with structural variations.A single candidate NLR was identified by anchoring RNA sequencing reads from susceptible mutants to ONT contigs and was validated by virus-induced gene ***69 is likely a newly evolved NLR and was discovered in only one location across the wild emmer wheat distribution range in ***69 was successfully introgressed into cultivated wheat,and a diagnostic molecular marker was used to accelerate its deployment and pyramiding with other R-genes.

关键词： cluster resistance Israel

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人类排放情景的设计与全球变暖预估

气候变化研究进展 2024年第2期20卷 261-264页

作者：赵宗慈罗勇黄建斌清华大学地球系统科学系北京100084 中国气象局国家气候中心北京100081 中国科学院大学资源环境学院北京100049

1气候变化的原因全球气候变化除地球系统内部变率外,自然强迫和人为强迫是重要的外部驱动力。其中自然强迫包括太阳活动和火山活动。人为强迫即人类活动,包括大量化石燃料燃烧排放温室气体、土地利用,以及气溶胶与污染排放等,其强度取... 详细信息

1气候变化的原因全球气候变化除地球系统内部变率外,自然强迫和人为强迫是重要的外部驱动力。其中自然强迫包括太阳活动和火山活动。人为强迫即人类活动,包括大量化石燃料燃烧排放温室气体、土地利用,以及气溶胶与污染排放等,其强度取决于人口发展与变化、社会经济发展、技术变化及其内部的协调性等。本文重点给出人类强迫的影响。IPCC第六次评估报告明确表明,近百年特别是近几十年来观测到的全球变暖归因为人类活动的影响。

关键词：太阳活动火山活动排放情景全球变暖社会经济发展全球气候变化人类强迫变率