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Allometric relationships between primary size measures and sapwood area for six common tree species in snow-dependent ecosystems in the Southwest United States

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Journal of Forestry Research 2020年第6期31卷 2171-2180页

作者： Bhaskar Mitra Shirley A.Papuga mr.ss alexander.tyson lee swetnam Nate Abramson School of Natural Resources and Environment University of ArizonaTucsonAZ 85721USA Department of Geology Wayne State UniversityDetroitMI 48202USA Laboratory of Tree-Ring Research University of ArizonaTucsonAZ 85721USA BIO5 Institute University of ArizonaTucsonAZ 85721USA Department of Hydrology and Water Resources University of ArizonaTucsonAZ 85721USA

High-elevation,snow-dependent,semiarid ecosystems across southwestern United States are expected to be vulnerable to climate change,including drought and fi re,with implications for various aspects of the water *** that end,much less is known about the dynamics of transpiration,an important component of the water cycle across this *** the individual-tree scale,transpiration is estimated by scaling mean sap fl ux density by the hydroactive sapwood area(SA).SA also remains a key factor in eff ectively scaling individual tree water-use to stand *** across large spatial scales is normally established by relating SA of a few trees to primary size measures,e.g.,diameter at breast height(DBH),tree height(H),or canopy diameter(CD).Considering the importance of SA in scaling transpiration,the primary objective of this study was therefore to establish six species-specifi c(aspen,maple,white fi r,ponderosa pine,Douglas fi r,Englemann spruce)allometric relationships between SA and three primary size measures(DBH,CD,or H)across two high-elevation,snow-dependent,semiarid ecosystems in New Mexico and *** on multiple statistical criteria(coeffi cient of determination,index of agreement,Nash–Sutcliff e effi-ciency)and ease of measurement in the forest,we identifi ed DBH as the primary independent variable for estimating SA across all *** on group regression analysis,we found allometric relationships to be signifi cantly(pss diff erent ***,our allometric relationships provide a valuable database for estimating transpiration at diff erent spatial scales from sap fl ow data in some of our most vulnerable ecosystems.

关键词： Allometry Diameter at breast height Mountain ecosystem Sapwood area Southwestern USA

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Nitrate reductase activity in high-mountain plants:a test across species,growth form and habitat type

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Journal of Plant Ecology 2019年第3期12卷 519-530页

作者： Adam Rajsz Bronisław Wojtuń Lucyna mróz Ludwik Żołnierz alexander J.Kempers Department of Ecology Biogeochemistry and Environmental ProtectionWrocław Universityul.Kanonia 6/850-328 WrocławPoland Department of Botany and Plant Ecology University of Environmental and Life Sciences.Pl.Grunwaldzki 24a50-363 WrocławPoland Radboud University Nijmegen Institute for Water and Wetland ResearchDepartment of Environmental ScienceHeyendaalseweg 1356525 AJ NijmegenThe Netherlands

Aims For many terrestrial plants,nitrate is the most important form of available soil nitrogen for ***,many plant species,which grow on acidic,ammonium-dominated soils,exhibit a con-stantly low level of nitrate reductase activity(NRA).Little is known about NRA in high-mountain vascular plants in similar *** tested the hypothesis that high-mountain vascular plants in acidic and ammonium-dominated habitats have low levels of *** Twenty-six plant species of the families Asteraceae,Ericaceae,Poaceae,Polygonaceae,Salicaceae,Pinaceae,Ranunculaceae,Woodsiaceae,Cyperaceae,Juncaceae,Rosaceae and Urticaceae representing different growth forms were investigated in seven native and anthropogenic habitats of subalpine and alpine belts of the Karkonosze(Hercynian middle-mountains,Central Europe),with respect to leaf NRA and mineral nitrogen forms in *** was measured by an in vivo assay for the first time directly in the field using portable water *** Findings An NRA study of vascular plants from high mountains is presented for the first time,and most of the studied subalpine and alpine species were subjected to field measurements for the first time *** among species,families,growth forms and habitats for NRA were *** differences reflected mainly the taxonomical position and in part ecological *** analysis confirmed that variance component showed that enzyme activities were mostly explained by plant species and ***,the subalpine and alpine species from their native habitats are characterized by very low and low ability for nitrate *** also compared NRA with Ellenberg’s N val-ues for the studied *** a regression equation,N values of some species were calculated for the first time and corrected for the others.

关键词： nitrate reductase subalpine and alpine habitats Ellenberg's N values the Karkonosze Hercynian middle-mountains

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UAS-Based Plant Phenotyping for Research and Breeding Applications

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Plant Phenomics 2021年第1期3卷 242-262页

作者： Wei Guo Matthew E.Carroll Arti Singh tyson L.swetnam Nirav Merchant Soumik Sarkar Asheesh K.Singh Baskar Ganapathysubramanian Graduate School of Agricultural and Life Sciences The University of TokyoJapan Department of Agronomy Iowa State UniversityAmesIowaUSA BIO5 Institute University of ArizonaTucsonUSA Data Science Institute University of ArizonaTucsonUSA Department of Mechanical Engineering Iowa State UniversityAmesIowaUSA

Unmanned aircraft system(UAS)is a particularly powerful tool for plant phenotyping,due to reasonable cost of procurement and deployment,ease and flexibility for control and operation,ability to reconfigure sensor payloads to diversify sensing,and the ability to seamlessly fit into a larger connected phenotyping *** advantages have expanded the use of UAS-based plant phenotyping approach in research and breeding *** paper reviews the state of the art in the deployment,collection,curation,storage,and analysis of data from UAS-based phenotyping *** discuss pressing technical challenges,identify future trends in UAS-based phenotyping that the plant research community should be aware of,and pinpoint key plant science and agronomic questions that can be resolved with the next generation of UAS-based imaging modalities and associated data analysis *** review provides a broad account of the state of the art in UAS-based phenotyping to reduce the barrier to entry to plant science practitioners interested in deploying this imaging modality for phenotyping in plant breeding and research areas.

关键词： breeding Plant payload

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Synthesis and Single-crystal X-ray Studies of (E)-ethyl 2-fluoro-2-(3-oxoisobenzofuran-1(3H)-ylidene) Acetate

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Chinese Journal of Structural Chemistry 2013年第8期32卷 1139-1142页

作者： Muhammad Adeel Peter Langer alexander Villinger Department of Chemistry Gomal University Dera Ismail KhanKPK Pakistan Institute of Chemistry University of Rostock

The title compound （E）-ethyl 2-fluoro-2-（3-oxoisobenzofuran-1（3H）-ylidene） aceta- te was synthesized as an unexpected product by the reaction ofphthalyl dichloride with bis-silylenol ether, which is not in accordance with our previous studies. The title compound was characterized by single-crystal X-ray diffraction, 1H Nmr, 13C Nmr, 19F Nmr, GCMS, HRMS and IR. The crystal （C12HgFO4, mr = 236.19） belongs to the monoclinic system, space group P21/c, a = 19.1609（8）, b = 7.9831（3）, c = 13.7715（6） A, V= 2106.13（15） A3, Z= 8, Dx = 1.490 Mg m-3, MoKa radiation, 2 = 0.71073 A,μ = 0.12 mm-1, F（000） = 976, the final R = 0.025 and wR = 0.1300 for 4505 observed reflections with I〉 2σ（I）.

关键词： organo fluorine compounds crystal structure 1,3-bis-silylenol ether,phthalyl dichloride condensation reaction

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Characterisation of pore fluid salinity dependent evaporative dewatering of kaolin using dielectric spectroscopy

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 112-125页

作者： Partha Narayan Mishra Thierry Bore alexander Scheuermann Ling Li Geotechnical Engineering Centre School of Civil EngineeringThe University of QueenslandSt Lucia4072Australia School of Engineering Westiake UniversityHangzhouChina

Realising the importance of pore fluid salinity on the dewatering behaviour of fine-grained porous systems,the present study systematically investigated such impacts on temporal moisture dynamics of kaolin subjected to evaporative dewatering.A detailed discussion is provided pertaining to the background processes dictating evaporative dewatering response and corresponding alterations in the dielectric behaviour of *** dependent dielectric spectra of soil,which can be considered as the fingerprint of the transient changes in the condition of water phase within the pore system of the soil and associated densification,are monitored in real time during dewatering using an open-ended coaxial probe with a vector network *** spatial sensitivity of the coaxial probe has been quantified through layered media *** the results of volume change behaviour of the material along with its moisture loss response,the study characterised the hydro-mechanical response of the material from the windows of frequency dependent dielectric spectroscopy.

关键词： Kaolin Evaporative dewatering Pore fluid salinity Electromagnetic(EM)methods Vector network analyser Dielectric permittivity Sensitivity analysis

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Salinity effects on soil shrinkage characteristic curves of fine-grained geomaterials

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 181-191页

作者： Partha Narayan Mishra alexander Scheuermann Thierry Bore Ling Li School of Civil Engineering University of Queensland

Fine-grained clayey soils are prone to substantial volume changes during desiccation in response to the dynamics of their moisture regime,and are of critical importance in several geotechnical and geoenvironmental engineering applications. As such, the complex interactions between the fraction of soil solids and the ionic pore fluid play a critical role in governing such volume changes, and have been the focus in studies dealing with marine geotechnology, mine-tailing ponds, engineered barrier systems, *** this in mind, the present investigation evaluates the volume changes and accompanying densification from a saturated slurry state to a constant volume state of a reference fine-grained geomaterial,kaolin, subjected to evaporative dewatering. For this purpose, several parametric studies involving determination of soil shrinkage characteristic curves(ssCCs) of kaolin under the influence of varied salt constituents and concentrations of pore fluid are performed. Furthermore, a critical assessment of ssCCs depicting progressive shrinkage and volume change behaviour of geomaterials is provided, followed by the analysis of experimentally obtained ssCCs of the kaolin to explore the impacts of pore fluid ***, the ssCCs are parameterised with a predictive model and the fitting parameters are used to quantitatively demonstrate the salinity-dependent volume change response of a representative finegrained porous system.

关键词： Kaolin Pore fluid salinity Soil shrinkage curves Pore space dynamics Geotechnical engineering

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CALCULATION OF ELASTIC DAMPING CHARACTERISTICS OF ROTOR SUPPORT MADE OF METAL RUBBER MATERIAL UNDER VARIABLE LOADS

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 33-37页

作者： JIANG Hongyuan YAN Hui AO Hongrui alexander M Ulanov School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Department of Aircraft and Engine Structure Design Samara State Aerospace University Samara 443086 Russia

A metal rubber（mr） dry friction damper was designed based on the load supported by the rotor. An experimental apparatus for obtaining hysteresis loops of support under the precession load was designed. The elastic-damping characteristics of the ring-shaped mr damper used as a rotor support under variable loads were presented by studying the hysteresis loops of the damper. The vibration rigidity and the energy dissipation coefficient were calculated from the hysteresis loops, based on the description of the deformation process of the mr element with simple structure in a dimensionless coordinating system. The calculation results showed that the energy dissipation coefficient in the inner of mr element and on the boundary between the damper and the frame of the rotor support were approximately equal. The comparison of the hysteresis loops for a precession load and a one-axial load indicated a large difference when the coefficient of the energy dissipation and the stiffness of the mr damper were concerned.

关键词： Rotor support Precession load Stiffness Energy dissipation coefficient Metal rubber

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Syntheses, Crystal Structures and Magnetic Properties of Cobalt(Ⅱ) and Manganese(Ⅱ) Coordination Polymers Constructed from 5-(Pyridin-4-yl)Isophthalate Ligands

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Chinese Journal of Structural Chemistry 2014年第4期33卷 626-634页

作者：高竹青李红晋 M.Kirillov alexander 顾金忠 School of Chemical and Biological Engineering Taiyuan University of Science and Technology Centro de Química Estrutural Complexo I Instituto Superior TécnicoThe University of Lisbon Av. Rovisco Pais1049-001 Lisbon Portugal College of Chemistry and Chemical Engineering Lanzhou University

Two coordination polymers, namely {[Co（L）（H2O）]·H2O}n （1） and [Mn（L）（phen）]n （2, H2L = 5-（pyridin-4-yl）isophthalic acid, phen = 1,10-phenanthroline）, have been hydrothermally synthesized and characterized by elemental analysis, IR, TG, magnetic properties, and single-crystal X-ray diffraction. 1 belongs to the triclinic system, space group Pī with α = 7.2188（7）, b = 10.0835（8）, c = 10.2069（7）？, α = 113.713（7）, β = 99.490（7）, γ = 104.516（8）o, V = 628.24（9）？3, C13H11NCoO6, mr = 336.16, Z = 2, Dc = 1.777 Mg/m3, μ（MoKα） = 1.395 mm–1, F（000） = 342, S = 1.041, the final R = 0.0381 and wR = 0.0819 for 3744 observed reflections （I 〉 2σ（I）） and R = 0.0448 and wR = 0.0874 for all data. 2 belongs to the monoclinic system, space group P2/c with α = 12.9185（3）, b = 10.4343（2）, c = 31.7650（6）？, β = 101.282（2）o, V = 4199.08（13）？3, C50H30N6Mn2O8, mr = 952.68, Z = 4, Dc = 1.507 Mg/m3, μ（MoKα） = 5.447 mm–1, F（000） = 1944, S = 1.128, the final R = 0.1003 and wR = 0.1052 for 8247 observed reflections （I 〉 2σ（I）） and R = 0.2595 and wR = 0.2625 for all data. Single-crystal X-ray diffraction studies show that compound 1 features a 2D sheet structure based on a dicobalt（II） subunit, which is further extended into a 3D metal-organic supramolecular framework by O–H… hydrogen bond. Compound 2 also possesses a 2D sheet, which is held together into a 3D supramolecular architecture via C–H… hydrogen bond and π-π stacking interactions. Magnetic studies for compound 2 show antiferromagnetic coupling between the adjacent metal centers, with J = –11.8 cm–1 and g = 2.12 for 2.

关键词： coordination polymer crystal structrue magnetic properties

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烧友信条:醉翁之意不在酒——只爱接收,不为看。

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卫星电视与宽带多媒体 2012年第1期 33-35页

作者： mr.alexander.Wiese 罗世刚邢天

拉尔夫·塞安科（Ralf Sunke）是一化“高烧”23年的老烧友，自1988年开始迷上天线，

关键词：接收酒天线

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Stroke-like onset of brain stem degeneration presents with unique mrI sign and heterozygous NMNAT2 variant:a case report

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Translational Neurodegeneration 2016年第1期5卷 181-185页

作者： alexander Schulz Franziska Wagner Martin Ungelenk Ingo Kurth Christoph Redecker Hans Berger Department of Neurology Jena University HospitalFriedrich Schiller University JenaJena 07747Germany Department of Genetics and Program in Cellular Neuroscience Neurodegeneration and RepairYale University School of MedicineNew HavenCT 06510USA Institute of Human Genetics Jena University HospitalFriedrich-Schiller-University JenaJena 07743Germany Institute of Human Genetics Uniklinik RWTH AachenAachen 52074Germany

Background:Acute-onset neurodegenerative diseases in older patients are rare clinical cases,especially when the degeneration only affects specific regions of the nervous *** neurological disorders have been described in which the degeneration of brain parenchyma originates from and/or primarily affects the brain *** diagnosis in these patients,however,is often complicated due to a poor understanding of these diseases and their underlying *** presentation:In this manuscript we report on a 73-year-old female who had experienced a sudden onset of complex neurological symptoms that progressively worsened over a period of 2 *** evaluation had suggested a mrI-negative stroke as underlying *** combination of patient’s medical history,clinical examination and exceptional pattern of brain stem degeneration presenting as“kissing swan sign”in mr imaging was strongly suggestive of acute onset of alexander’s *** leukoencephalopathy is caused by GFAP(glial fibrilary acidic protein)gene mutations and may present with brain stem atrophy and stroke-like onset of symptoms in elderly ***,a pathognomonic GFAP gene mutation could not be identified by Sanger ***:After an extended differential diagnosis and exclusion of other diseases,a definite diagnosis of the patient’s condition presently remains ***,whole-exome sequencing performed from patient’s blood revealed 12 potentially disease-causative heterozygous variants,amongst which several have been associated with neurological disorders in vitro and in vivo–in particular the axon degeneration-related NMNAT2 gene.

关键词： Brain stem atrophy Dementia alexander’s disease Whole-exome sequencing Kissing swan sign NMNAT2 Axon degeneration

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