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Reaction of Polymer-supported Selenovinyl Bromide with Grignard Reagents: A Facile Route to the Synthesis of (e)-1, 2-Disubstituted Olefins

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Chinese Chemical Letters 2005年第8期16卷 1001-1003页

作者： e TANG Xiang Jin LIN Lu Ling WU Department of Chemistry Zhejiang University （Xixi Campus） Hangzhou 310028

Polymer-supported selenovinyl bromide, easily prepared from polymer-supported selenenyl bromide with acetylene, reacts with different Grignard reagents using a step-by-step strategy to obtain （e）-1, 2-disubstituted ... 详细信息

关键词： Polymer-supported selenovinyl bromide Grignard reagents disubstituted ethenes.

Nighttime sap flow of Acacia mangium and its implications for nighttime transpiration and stem water storage

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Journal of Plant ecology 2012年第3期5卷 294-304页

作者： Hua Wang Ping Zhao dirk Hölscher Quan Wang Ping Lu Xi A.Cai Xiao P.Zeng South China Institute of Botany Chinese Academy of SciencesGuangzhou 510650China Institute of Forestry and Pomology Beijing Academy of Agriculture and Forestry SciencesBeijing 100093China Research Center for eco-environmental Sciences Chinese Academy of SciencesBeijing 100085China Department of Tropical Silviculture and Forest ecology University of Göttingen37077 GöttingenGermany Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan energy Resources of Australia Ltd GPO Box 2394DarwinNorthern Territory0801Australia

Aims Nighttime sap flow of trees may indicate transpiration and/or recharge of stem water storage at *** paper deals with the water use of Acacia mangium at night in the hilly lands of subtropical South *** primary goal was to reveal and understand the nature of nighttime sap flow and its functional *** Granier’s thermal dissipation method was used to determine the nighttime sap flux of *** exchange system was used to estimate nighttime leaf transpiration and stomatal conductance of studied *** Findings Nighttimesap flowwas substantial and showed seasonal variation similar to the patterns of daytime sap flowin *** nighttime sap flow was higher in the less precipitation year of 2004(1122.4 mm)than in the more precipitation year of 2005(1342.5 mm)since more daytime transpiration and low soil water availability in the relatively dry 2004 can be the cause of more nighttime sap *** vapor pressure deficit and air temperature were significantly correlated with nighttime sap flow,they could only explain a small fraction of the variance in nighttime sap *** total accumulated water loss(e_(L))by transpiration of canopy leaves was only;2.6–8.5%of the total nighttime sap flow(e_(t))during the nights of July 17–18 and 18–19,***,it is likely that the nighttime sap flow was mainly used for refillingwater in the *** stem diameter at breast height,basal area and sapwood area explained much more variance of nighttime water recharge than environmental factors and other tree form features,such as tree height,stem length below the branch,and canopy *** contribution of nighttime water recharge to the total transpiration ranged from 14.7 to 30.3%depending on different DBH class and was considerably higher in the dry season compared to the wet season.

关键词： heat dissipation method nighttime sap flow nighttime leaf transpiration stem water recharge

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吴耀祖教授与我

力学与实践 2025年第6期46卷 1129-1131页

作者：黄锷自然资源部第一海洋研究所山东青岛 266061

在吴耀祖教授的朋友中，我应该算是后来的。虽然早就听说过他的名字，但直到1995年底，我才在从当时的工作单位——美国NASA戈达德太空飞行中心赴加州理工学院访问时，第一次见到了吴教授。当时在他主持的学术报告会中报告我在波动融合... 详细信息

在吴耀祖教授的朋友中，我应该算是后来的。虽然早就听说过他的名字，但直到1995年底，我才在从当时的工作单位——美国NASA戈达德太空飞行中心赴加州理工学院访问时，第一次见到了吴教授。当时在他主持的学术报告会中报告我在波动融合方面的发现，即:短波变长并非是通过增大波长来实现的，而是由于短波通过局部和离散(非连续)将两个波动融合为一个，并推广到n个波动融合为(n-1)个波。报告结束后，吴教授把我带到他的办公室，除鼓励外还给了我两个建议：首先，建议我将在研究中使用的经验模态分解方法和希尔伯特变换申请专利；其次，访问加州理工学院一段时间，深入研究这些方法。

关键词：加州理工学院经验模态分解方法希尔伯特变换太空飞行戈达德学术报告会吴教授申请专利

包被尿素与蒸汽压片玉米组合对活体外瘤胃氨氮释放和发酵参数的影响

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中国农业大学学报 2007年第3期12卷 41-45页

作者：辛杭书任丽萍孙长勉 e.A.dirk 刘庆平孟庆翔动物营养学国家重点实验室美国兰科矿物质公司弗吉尼亚23842 国际原料公司佛罗里达33569

选用包被尿素、普通尿素（负对照）和大豆分离蛋白（正对照）作为氮源，普通玉米（对照）和蒸汽压片玉米作为碳源，采用2×3因子试验设计，利用活体外人工瘤胃产气法，研究包被尿素与蒸汽压片玉米组合对活体外瘤胃氮氮释放速度和发酵参... 详细信息

选用包被尿素、普通尿素（负对照）和大豆分离蛋白（正对照）作为氮源，普通玉米（对照）和蒸汽压片玉米作为碳源，采用2×3因子试验设计，利用活体外人工瘤胃产气法，研究包被尿素与蒸汽压片玉米组合对活体外瘤胃氮氮释放速度和发酵参数的影响。结果表明：在瘤胃发酵1～8h期间，无论基于哪种碳源，包被尿素处理的NH3-N值比普通尿素处理降低11．1％～17．1％（P〈0．001），也低于大豆分离蛋白处理；蒸汽压片玉米处理的氮氮释放速度比对照组降低3．3％～13．7％（P〈0．001）；并在发酵前4h中，有显著互作效应（P〈0．05）。蒸汽压片玉米处理的产气速度显著高于对照（0．1104h^-1，0．1226h^-1，P〈0．001），大豆分离蛋白的24h干物质消化率为73．13％，显著高于其他处理（P〈0．05）。普通玉米（对照）组的总挥发酸产量（101．33mmol／L，96．69mmol／L）和丁酸摩尔分数（13．58％，12．69％）显著高于蒸汽压片玉米处理组（P〈0．05），而处理组的丙酸摩尔分数（22．11％．21．68％）显著高于对照组（P〈0．05）。不同氮源与碳源的总挥发酸产量存在显著的互作效应（P〈0．05）。试验结果表明：包被尿素与蒸汽压片玉米组合可以显著减缓瘤胃氮氮释放速度，而对72h产气量及其他发酵参数没有明显影响。

关键词：包被尿素蒸汽压片玉米活体外瘤胃发酵氮氮释放发酵参数

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闪电侠奔驰SLS AMG e-Cell

汽车驾驶员 2010年第9期26卷 130-133页

作者：刘磊 dirk Weyenmeier（摄影）

科幻电影机器人瓦力中，靠电力驱动行动缓慢的机器人WALL—e给我们留下了深刻印象。而下面要介绍的这辆奔驰SLSAMG被称为“e-Cell”，同样是依靠电池的电力驱动，但其0—100公里加速仅用4秒。

关键词：奔驰 SLS 闪电电力驱动科幻电影机器人公里

Regulation of the water status in three co-occurring phreatophytes at the southern fringe of the Taklamakan Desert

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Journal of Plant ecology 2008年第4期1卷 227-235页

作者： Frank M.Thomas Andrea Foetzki dirk Gries Helge Bruelheide Xiangyi Li Fanjiang Zeng Ximing Zhang Department of Plant ecology Albrecht von Haller Institute for Plant SciencesGeorg-August-Universitat GottingenUntere Karspule 237073 GottingenGermany Present address:Department of Geobotany University of TrierBehringstraße 2154296 TrierGermany eidgenossisches Institut fur Agrarokologie und Landwirtschaft Forschungsanstalt AgroscopeReckenholzstrasse 1918046 ZurichSwitzerland Institute of Geobotany and Botanical Garden Martin Luther University Halle-WittenbergAm Kirchtor 106108 Halle(Saale)Germany Xinjiang Institute of ecology and Geography Chinese Academy of Sciences40 South Beijing Road830011 UrumqiChina

Aims We investigated the regulation of the water status in three predominant perennial C3 phreatophytes(Alhagi sparsifolia,Populus euphratica,Tamarix ramosissima)at typical sites of their occurrence at the southern fringe of the hyperarid Taklamakan Desert(north-west China).Methods In the foreland of the river oasis of Qira(Cele),we determined meteorological variables,plant biomass production,plant water potentials(WL)and the water flux through the *** calculated the hydraulic conductance on the flow path from the soil to the leaves(kSL)and tested the effects of kSL,WL and the leaf-to-air difference in the partial pressure of water vapour(Dw)on stomatal regulation using regression *** Findings Despite high values of plant water potential at the point of turgor loss,all plants sustained WL at levels that were high enough to maintain transpiration throughout the growing *** ***,stomatal resistance(rs;related to leaf area or leaf mass)was most closely correlated with kSL;whereas in ***,~70%of the variation in rs was explained by *** ***,leaf area-related rs was significantly correlated with WL and *** regulation mechanisms are in accordance with the growth patterns and the occurrence of the species in relation to their distance to the ground water.

关键词： aboveground growth extreme aridity stomatal conductance transpirational demand vapour pressure deficit

Longwave infrared multispectral image sensor system using aluminum-germanium plasmonic filter arrays Noor e

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Nano Research 2023年第7期16卷 10018-10025页

作者： Karishma Shaik Bryce Widdicombe Dechuan Sun Sam e John Dongryeol Ryu Ampalavanapillai Nirmalathas Ranjith R Unnithan Department of electrical and electronic engineering University of MelbourneParkvilleVIC 3010Australia Department of Biomedical engineering University of MelbourneParkvilleVIC 3010Australia Department of Infrastructure engineering University of MelbourneParkvilleVIC 3010Australia

A multispectral camera records image data in various wavelengths across the electromagnetic spectrum to acquire additional information that a conventional camera fails to *** the advent of high-resolution image sensors and color filter technologies,multispectral imagers in the visible wavelengths have become popular with increasing commercial viability in the last ***,multispectral imaging in longwave infrared(LWIR,8-14μm)is still an emerging area due to the limited availability of optical materials,filter technologies,and high-resolution *** from LWIR multispectral cameras can capture emission spectra of objects to extract additional information that a human eye fails to capture and thus have important applications in precision agriculture,forestry,medicine,and object *** this work,we experimentally demonstrate an LWIR multispectral image sensor with three wavelength bands using optical elements made of an aluminum(Al)-based plasmonic filter array sandwiched in germanium(Ge).To realize the multispectral sensor,the filter arrays are then integrated into a three-dimensional(3D)printed wheel stacked on a low-resolution monochrome thermal *** prototype device is calibrated using a blackbody and its thermal output has been enhanced with computer vision *** applying a state-of-theart deep learning method,we have also reconstructed multispectral images to a better spatial ***,our work demonstrates a versatile spectral thermography technique for detecting target signatures in the LWIR range and other advanced spectral analyses.

关键词： infrared plasmonics germanium(Ge) aluminum(Al) thermal optics longwave infrared(LWIR)multispectral system

25-hydroxycholecalciferol reverses heat induced alterations in bone quality in finisher broilers associated with effects on intestinal integrity and inflammation

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Journal of Animal Science and Biotechnology 2022年第2期13卷 499-519页

作者： Huaiyong Zhang Maryam Majdeddin Djoere Gaublomme Bernard Taminiau Matthieu Boone dirk elewaut George Daube Iván Josipovic Keying Zhang Joris Michiels Laboratory for Animal Nutrition and Animal Product Quality Department of Animal Sciences and Aquatic EcologyGhent University9000 GhentBelgium Key laboratory of Animal Disease-resistant Nutrition Ministry of EducationInstitute of Animal NutritionSichuan Agricultural UniversityYa’an 611130SichuanChina Unit Molecular Immunology and Inflammation VIB Center for Inflammation ResearchGhent University and Department of RheumatologyGhent University Hospital9000 GhentBelgium Department of Food Sciences-Microbiology University of Liège4000 LiègeBelgium Ghent University Centre for X-ray Tomography(UGCT) Ghent University9000 GhentBelgium Department of Physics and Astronomy Radiation Physics Research GroupGhent University9000 GhentBelgium

Background:Alterations in ambient temperature have been associated with multiple detrimental effects on broilers such as intestinal barrier disruption and dysbiosis resulting in systemic *** and 25-hydroxycholecalciferol(25-OH-D_(3))have shown to play a negative and positive role,respectively,in the regulation of bone *** the potential of 25-OH-D_(3)in alleviating heat induced bone alterations and its mechanisms was ***:Heat stress(HS)directly induced a decrease in tibia material properties and bone mass,as demonstrated by lower mineral content,and HS caused a notable increase in intestinal *** with dietary 25-OH-D_(3)reversed the HS-induced bone loss and barrier *** suffering from HS exhibited dysbiosis and increased expression of inflammatory cytokines in the ileum and bone marrow,as well as increased osteoclast number and *** changes were prevented by dietary 25-OH-D_(3)***,dietary 25-OH-D_(3)addition decreased abundance of B-and T-cells in blood,and the expression of inflammatory cytokines,especially TNF-α,in both the ileum and bone marrow,but did not alter the diversity and population or composition of major bacterial *** regard to bone remodeling,dietary 25-OH-D_(3)supplementation was linked to a decrease in serum C-terminal cross-linked telopeptide of type I collagen reflecting bone resorption and a concomitant decrement in osteoclast-specific marker genes expression(*** K),whereas it did not apparently change serum bone formation markers during ***:These data underscore the damage of HS to intestinal integrity and bone health,as well as that dietary 25-OH-D_(3)supplementation was identified as a potential therapy for preventing these adverse effects.

关键词： Bone remodeling HS Inflammation Intestinal barrier Tibial mass

Thermal conductivity of systems with a gap in the phonon spectrum

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Chinese Physics B 2018年第7期27卷 424-430页

作者： e Salamatov Udmurt Federal Research Center Ural Branch of the Russian Academy of Sciences

An original theoretical model for describing the low-temperature thermal conductivity in systems with a region of forbidden values （a gap） in the phonon spectrum is proposed. The model is based on new experimental results on the temperature dependence of the phonon diffusion coefficient in nanoceramics and dielectric glasses which showed a similar anomalous behavior of the diffusion coefficient in these systems that may be described under the assumption of a gap in the phonon spectrum. In this paper, the role of the gap in low-temperature behavior of the thermal conductivity, ~＇（T）, is analyzed. The plateau in the temperature dependence of the thermal conductivity is shown to correlate with the position and the width of the gap. The temperature dependence of thermal conductivity of such systems when changing the scat- tering parameters related to various mechanisms is studied. It is found that the umklapp process （U-processes） involving low-frequency short-wavelength phonons below the gap forms the behavior of the temperature dependence of thermal con- ductivity in the plateau region. A comparison of the calculated and experimental results shows considerable possibilities of the model in describing the low-temperature thermal conductivity in glass-like systems.

关键词： phononic band gap phonon diffusion coefficient thermal conductivity glassy crystals