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Responses of different Physiological Indices for Maize(Zea mays) to Soil Water Availability

Pedosphere 2011年第5期21卷 639-649页

作者： WU Yuan-Zhi HUANG Ming-Bin d. N. WARRINGTON State Key Laboratory of Soil Erosion and dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 (China) Shandong Provincial Key Laboratory of Soil Conservation and Environmental Protection School of Chemistry and Resources Environment Linyi University Linyi 276005 (China) Graduate University of Chinese Academy of Sciences Beijing 100049 (China) Northwest A&F University Yangling 712100 (China)

Knowledge of plant responses to soil water availability is essential for the development of effcient irrigation ***,notably different results have been obtained in the past on the responses of various physiological indices for different plants to soil water *** this study,the responses of various plant processes to soil water availability were compared with data from pot and field plot experiments conducted on maize(Zea mays L.).Consistent results were obtained between pot and field plot experiments for the responses of various relative plant indices to changes in the fraction of available soil water(FASW).A threshold value,where the relative plant indices began to decrease with soil drying,and a lower water limit,where the decline of relative plant indices changed to a very slow rate,were *** demand not only influenced the transpiration rate over a daily scale but also determined the difference in transpirational response to soil water availability among the transient,daily and seasonal time *** the seasonal scale,cumulative transpiration decreased linearly with soil drying,but the decrease of transpiration from FASW = 1 in response to water deficits did not affect dry weight until FASW = *** the other hand,the decrease in dry weight was comparable with plant height and leaf ***,the plant responses to soil water availability were notably different among various plant indices of maize and were influenced by the weather conditions.

关键词： dry weight evaporative demand fraction of available soil water plant growth transpiration

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Structural health monitoring of bridges in the State of Connecticut

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Earthquake Engineering and Engineering Vibration 2008年第4期7卷 427-437页

作者： Chengyin Liu Joshua Olund Alan Cardini Paul d＇Attilio Eric Feldblum John deWolf SP-SELLS Inc. Briarcliff Manor NY 10510 USA department of Civil and Environmental Engineering University of Connecticut 261 Glenbrook Rd Unit 2037 Storrs CT06269 USA dMJM Harris Boston MA 02110 USA Connecticut department of Transportation 280 West Street Rocky Hill CT 06067 USA

A joint effort between the Connecticut department of Transportation and the University of Connecticut has been underway for more than 20 years to utilize various structural monitoring approaches to assess different bridges in Connecticut. This has been done to determine the performance of existing bridges, refine techniques needed to evaluate different bridge components, and develop approaches that can be used to provide a continuous status of a bridge＇s structural integrity. This paper briefly introduces the background of these studies, with emphasis on recent research and the development of structural health monitoring concepts. This paper presents the results from three different bridge types： a post-tensioned curved concrete box girder bridge, a curved steel box-girder bridge, and a steel multi-girder bridge. The structural health monitoring approaches to be discussed have been successfully tested using field data collected during multi-year monitoring periods, and are based on vibrations, rotations and strains. The goal has been to develop cost-effective strategies to provide critical information needed to manage the State of Connecticut＇s bridge infrastructure.

关键词： structural integrity structural health monitoring field data vibrations

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铁基粉末冶金材料烧结程度的判定

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粉末冶金技术 2010年第2期28卷 150-154页

作者： thomas F. Murphy 韩凤麟(译) Scientist Laboratory Services Hoeganaes Corporation 1001 Taylors Lane CinnaminsonNJ 08077 USA 不详

烧结过程可改进压制-烧结的铁基材料的物理-力学性能。烧结时因扩散产生颗粒结合与合金化;随着烧结时间增长,强化材料性能。烧结的作用通过显微组织特征(诸如颗粒边界与孔隙边缘)的变化可以看出。烧结的一些改进表现为颗粒边界消失,孔... 详细信息

烧结过程可改进压制-烧结的铁基材料的物理-力学性能。烧结时因扩散产生颗粒结合与合金化;随着烧结时间增长,强化材料性能。烧结的作用通过显微组织特征(诸如颗粒边界与孔隙边缘)的变化可以看出。烧结的一些改进表现为颗粒边界消失,孔隙边缘变得较平滑和颗粒间尖角特征数量减少。一般将这些特征与特性的外观和它们发生的频率一起当做是烧结程度。用众所周知的体视技术(Stereological practies)与适当制备的金相试样,可以判定烧结程度。关于判定与区分烧结程度不同的材料,将讨论3种试验方法。另外,将用烧结时间不同的铁-铜-碳预混合粉材料的图像来说明这些显微组织的变化。

关键词：铁基粉末冶金材料烧结烧结程度判定

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ROBUSTNESS OF AN UPWINd FINITE dIFFERENCE SCHEME FOR SEMILINEAR CONVECTION-dIFFUSION PROBLEMS WITH BOUNdARY TURNING POINTS

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Journal of Computational Mathematics 2003年第4期21卷 401-410页

作者： Torsten Linfi (Institut fur Numerische Mathematik, Technische Universitdt dresden, d-01062 dresden, Germany) Institut fiir Nwnerisclie Mathematik Technische Universitdt Dresden 德国 D-01062 Dresden

We consider a singularly perturbed semilinear convection-diffusion problem with a boundary layer of attractive turning-point type. It is shown that its solution can be decomposed into a regular solution component and a layer component. This decomposition is used to analyse the convergence of an upwinded finite difference scheme on Shishkin meshes.

关键词： Convection-diffusion Singular perturbation Solution decomposition Shishkin mesh.

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Kinetics of fluorescence properties of Eu^(3+) ion in strontium-aluminiumbismuth-borate glasses

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Journal of Rare Earths 2014年第12期32卷 1140-1147页

作者： M.dhamodhara Naidu d.Rajesh A.Balakrishna Y.C.Ratnakaram department of Physics Sri Venkateswara University

Eu3＋ doped strontium-aluminium-bismuth-borate glasses with the chemical composition（50–x）B2O3＋20Bi2O3＋7Al F3＋ 8Sr O＋15Sr F2＋x Eu2O3（where x=0.1 mol.%, 0.5 mol.%, 1.0 mol.% and 1.5 mol.%） were prepared by the conventional melt quenching *** properties of the prepared glasses were analysed through X-ray diffraction（XRd）, scanning electron microscopy（SEM）, energy dispersive spectroscopy（EdS） and Raman spectral *** stability of glass was analysed by differential thermal analysis（dTA） *** characteristics were studied using excitation, emission spectra and decay curves of Eu3＋ doped strontium-aluminium-bismuth-borate *** Judd-Ofelt（J-O） intensity parameters, Ωλ（λ=2, 4 and 6） were obtained using emission spectra and was used to identify the nature of Eu3＋ ions with their surrounding *** J-O parameters the transition probabilities（A）, stimulated emission cross-sections σE p, branching ratios（βR） and radiative lifetimes（τmeas and τcal） were evaluated for the 5d0→7F J（J=0, 1, 2, 3 and 4） transition of Eu3＋ ions in the present *** decay profiles were found to be non exponential for all the concentrations and the measured lifetimes（τmeas） were obtained from the decay *** higher values of A, σE p, βR and quantum efficiency（η） for 5d0→7F2 emission transition at 617 nm confirmed the present glass was as active medium for red laser emission applications.

关键词： absorption photoluminescence Judd-Ofelt analysis decay curves rare earths

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The Effects of Coil Current distribution in a Cylindrical Electron Cyclotron Resonance Reactor

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Chinese Physics Letters 1994年第12期11卷 747-750页

作者： WU Hanming d.B.Graves LI Ming WANG Qin Institute of Mechanics Academia SinicaBeijing 100080 department of Chemical Engineering University of California BerkeleyCA 94720USA China Central Radio and TV University Beijing 100032

Using a 2-d hybrid model,the authors have found that external currents play an important role in the plasma parameters in the *** plasma density,temperature and electrostatic potential would be significantly influence... 详细信息

关键词： Electron currents electrostatic

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Cyclic patterns of incidence rate for skin malignant melanoma:association with heliogeophysical activity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第6期9卷 489-495页

作者： Borislav d.dIMITROV Mariana I.RACHKOVA Penka A.ATANASSOVA BORdANI Alzano Lombardo(BG)24022ItalyDepartment of Social Medicine and Health ManagementMedical UniversityPlovdiv 4000Bulgaria ASSON-93 Research Co. Mount ProspectILL 60056USA department of Neurology Medical UniversityPlovdiv 4000Bulgaria

Background： Our previous studies revealed cyclicity in the incidence rate of skin malignant melanoma （SMM; ICd9, dx： 172） in the Czech Republic （period T=7.50～7.63 years）, UK （T= 11.00 years） and Bulgaria （T= 12.20 years）. Incidences com- pared with the sunspot index Rz （lag-period dT=＋2, ＋4, ＋6, ＋ 10 or ＋ 12 years） have indicated that maximal rates are most likely to appear on descending slopes of the ;ll-year solar cycle, i.e., out of phase. We summarized and explored more deeply these cyclic variations and discussed their possible associations with heliogeophysical activity （HGA） components exhibiting similar cyclicity. Methods： Annual incidences of SMM from 5 countries （Czech Republic, UK, Bulgaria, USA and Canada） over various time spans during the years 1964-1992 were analyzed and their correlations with cyclic Rz （sunspot number） and aa （planetary geomagnetic activity） indices were summarized. Periodogram regression analysis with trigonometric approximation and phase-correlation analysis were applied. Results： Previous findings on SMM for the Czech Republic, UK and Bulgaria have been validated, and cyclic patterns have been revealed for USA （T=8.63 years, P〈0.05） and Canada （Ontario, T=9.91 years, P〈0.10）. Also, various ＇hypercycles＇ were established （T=45.5, 42.0, 48.25, 34.5 and 26.5 years, respectively） describing long-term cyclic incidence patterns. The association of SMM for USA and Canada with Rz （dT=＋6 and ＋7 years, respectively） and aa （dT=-10 and ＋9 years, respectively） was described. Possible interactions of cyclic non-photic influences （UV irradiation, Schumann resonance signal, low-frequency geomagnetic fluctuations） with brain waves absorbance, neuronal calcium dynamics, neuro-endocrine axis modulation, melatonin/serotonin disbalance and skin neuro-immunity impairment as likely causal pathways in melanoma appearance, were also discussed. Conclusion： The above findings on cyclicity and temporal association of SMM with cyclic environmental factors

关键词： Melanoma incidence Cyclicity Heliogeophysical activity (HGA) Forecasting Skin neurobiology

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An efficient one-pot three-component synthesis and antimicrobial evaluation of tetra substituted thiophene derivatives

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Chinese Chemical Letters 2014年第7期25卷 1099-1103页

作者： Pravinkumar N.Sable Swastika Ganguly Pravin d.Chaudhari department of Pharmaceutical Sciences Birla Institute of TechnologyMesra Ranchi 835215 India department of Pharmaceutical Chemistry Progressive Education Society’s Modern College of Pharmacy Nigdi Pune 411044 India

A convenient one-pot three-component method for the preparation of tetra-substituted thiophene derivatives has been developed. Reaction ofacetyl acetone 1, phenyl isothiocynate 2 and 2-chloromethyI derivatives 3a-3c in the presence of potassium carbonate afforded the target compounds, namely ethyl 2-（4-acetyl-3-methyl-5-（phenylamino）thiophen-2-yl）-2-oxoacetate derivatives 4a-4e, ethyl 3-（4- acetyl-3-methyl-5-（phenylamino）thiophen-2-yl）-3-oxopropanoate derivatives 4f-4i, di（（4-acetyl-3- methyl-5-phenylamino）thiophen-2-yl）ketone derivatives 4j-4n in reasonable overall yields. The synthesized compounds were screened for antirnicrobial activity. The detailed synthesis, spectroscopic data and antimicrobial activities of synthesized compounds were reported.

关键词： Thiophene Multicomponent reaction One pot reaction Antimicrobial agents

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Thermal Characteristics in the Cutting of Inconel 718 Superalloy Using CW Nd:YAG Laser

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Journal of Materials Science & Technology 2010年第4期26卷 362-366页

作者： d.G. Ahn K.W. Byun M.C. Kang department of Mechanical Engineering Chosun University 375 Seosuk-dong Dong-gu Gwang-ju 501-759 Korea Hybrid Materials Solution National Core Research (NCRC) Pusan National University San 30 Changjeon-dong Keumjeong-gu Busan 609-735 Korea

The objective of the this study is to investigate the effects of cutting parameters on thermal characteristics, including practical cutting regions, the formation of the kerfwidth and the heat transfer phenomenon, in the cutting of Inconel 718 super-alloy sheets using a CW Nd：YAG laser. From the results of the experiments, the influence of process parameters on both the practical cutting region and the kerfwidth has been examined. In addition, it has been shown that the kerfwidth of the specimen lies in the range of 0.53-0.61 mm. In order to examine characteristics of the heat transfer during the laser cutting process, a three-dimensional quasi-steady heat transfer analysis has been performed using the commercial code SYSWELd V9.0. From the results of the analysis, the influence of cutting parameters on the temperature distribution in the vicinity of the cut section has been quantitatively evaluated. Based on these results, optimal cutting conditions have been estimated.

关键词： CW Nd:YAG laser Inconel 718 Kerfwidth Quasi-steady heat transfer analysis

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Nitrogen and Carbon Isotope data of Olenekian to Anisian deposits from Kamenushka/South Primorye, Far-Eastern Russia and Their Palaeoenvironmental Significance

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Journal of Earth Science 2018年第4期29卷 837-853页

作者： Yuri d Zakharov Micha Horacek Alexander M Popov Liana G Bondarenko Far Eastern Geological Institute of Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia BLT Wieselburg Research Center HBLFA Francisco-Josephinum Wieselburg 3250 Austria Institute of Lithospheric Research Vienna University Vienna 1090 Austria

The Kamenushka Formation, exposed in the northern part of South Primorye （Kamennshka-1 and Kamenushka-2 sections）, is one of the few localities in the world with richly fossiliferous Lower-Upper Olenekian sedimentary successions. Lower to Middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete ^15Non- and ^13Corg- records for the Lower Triassic of this region. Nine N- isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the Mesohedenstroemia bosphorensis Zone （upper part）, Shimanskyites shimanskyi and Neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the Middle Spathian part of the Nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and Majiashan sections.

关键词： Triassic N- and C-isotopes palaeoclimatology bio- and chemostratigraphy Pri- morye Russia.

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