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Journal of Materials Science & technology 2021年第34期93卷 60-70页

作者： Z.H.Wang B.Niu Q.Wang c.Dong J.c.Jie t.M.Wang t.G.Nieh Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Department of Materials Science and Engineering The University of TennesseeKnoxville37996TennesseeUSA

the development of ultrastrong maraging stainless steels(MSSs)is always in high ***,traditional high-strength MSSs generally exhibit early plastic instability with a low uniform strain since the precipitated nanoparticles are non-coherent with the body-centered-cubic(Bcc)lath martensitic ***,we design a novel ultrahigh strength MSS(Fe-5.30 cr-13.47 Ni-3.10 Al-1.22 Mo-0.50 W-0.23 Nb-0.03 c-0.005 B,wt.%)using a cluster formula approach.A fabulous microstructure consisting of a uniform distribution of high-density coherent B2-Ni Al nanoprecipitates(3-5 nm)in Bcc martensitic matrix was successfully *** alloy has not only an exceedingly high ultimate tensile strength of 2.0 GPa,but also a decent uniform elongation of 4.2%-5.1%,which is almost triple of the value observed in existing *** present an in-depth discussion on the origins of ultrahigh strength and uniform plastic strain in the new alloy to validate our design strategy and further offer a new pathway to exploit highperformance MSSs.

关键词： Maraging stainless steel Ultrahigh strength coherent precipitation Strengthening mechanisms Uniform deformation

Operations Research: the Science of Better

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Operations Research: The Science of Better

temporal changes in nitrogen acquisition of Japanese black pine(Pinus thunbergii) associated with black locust(Robinia pseudoacacia)

中国运筹学会第七届学术交流会

作者： Richard c.larson Massachusetts Institute of technology cambridge Massachusetts 02139 USA President-Elect - INFORMS Institute For Operations Research and the Management Sciences

It is a deep honor for me today to give this talk before the most distinguished operationsresearchers in china. I sincerely thank you for the opportunity. I am particularly indebtedto Prof. Xiangsun ZHANG, Academy of Mathematics and System Sciences, for inviting me topresent this lecture. thank you! Operations Research, co-founded in World War Ⅱin the USA by Philip M. Morse, GeorgeKimball, Bernard Koopman and others, in the U.K. by Frederick Lanchester, Patrick Blackett,Frank Yates and others, was designed as an empirical science using all relevant scientific methodsto solve managerial decision problems.

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Journal of Forestry Research 2014年第3期25卷 585-589页

作者： M.L.Lopez c. c.Mizota Y.Nobori t.Sasaki t.Yamanaka Faculty of Agriculture Yamagata University1-23 Wakabamachi Tsuruoka Yamagata 997-8555 Japan Faculty of Agriculture Iwate University Division of Earth Science Graduate School of Natural Science and Technology Okayama University1-1 Naka 3-chome Tsushima Okayama Japan

the alien woody legume, black locust （Robinia pseudoaca-cia）, has invaded Japanese black pine （Pinus thunbergii） forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests after nematode infestation. Nitrogen fixation by legumes acceler-ates N cycling in forest ecosystems. We studied temporal change in the annual tree-ring resolution N stable isotope composition （δ15N, a per mil deviation of δ15N/14N ratio, relative to atmospheric N2δ15N=0‰） at two natural locations of Japanese black pine forest with black locust that differed in the time since black locust establishment （Shohnai in north-east and Kita-Kyushu in southwest Japan）. Analyzed tree-rings covered the period from 1990/1992 to 2009. N acquisition by Japanese black pine from black locust N input to the soil was evidenced by temporal shifting of N stable isotope composition on the annual pine tree rings. With pro-gressive development of the forest stand,δ15N values of earlier tree-ringsδ15N of -5‰） from black pine associated with black locust shifted to-wards values similar to those of black locustδ15N values nearly to-1‰）, which suggests acquisition of N by N2 fixation （Shohnai site）. In con-trast, in a forest where black locust had settled for two or three genera-tions, in a black pine stand （Kita-Kyushu site）, longer periods of N en-richment in the soil were reflected in the elevated tree-ringδ15N values of newly established black pine trees. Based on tree-ringδ15N data from the Shohnai site, we determined that about 10 years after black locust establishment, soil N had already been enriched by black locust N, this, in turn, contributed to N fertilization of surrounding trees in mixed stands.

关键词： δ15N natural abundance Japanese black pine black locust,nitrogen acquisition tree-ring

Use of Recycled Glass in Architectural Mortars

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武汉理工大学学报 2010年第17期32卷 231-234,245页

作者： POON c S LING t c B Department of civil and Structural Engineering The Hong Kong Polytechnic UniversityHong KongChina

In recent years,recycled glass has been widely used as aggregate replacements in concrete. Owing to the aesthetic potential of the coloured recycled glass,this research aims to fully utilize this advantage for their higher end uses,such as architectural mortar. In this study,architectural white cement mortar was produced with a self consolidating method using recycled glass as the aggregate. An adequate amount of Metakaolin was incorporated into the mortar to mitigate the adverse effect of alkali-silica reaction. the results show that the self-compacting method is suitable to produce architectural mortar containing up to 100% recycled glass. Overall,the performance of all the architectural mortar mixtures in terms of both fresh and hardened properties was good.

关键词： recycled glass self-compacting architectural mortar ASR flexural strength

Long-term trends in Extreme temperatures in Hong Kong and Southern china

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Advances in Atmospheric Sciences 2011年第1期28卷 147-157页

作者： t.c.LEE E.W.L.GINN Hong Kong Observatory

the observed long-term trends in extreme temperatures in Hong Kong were studied based on the meteorological data recorded at the Hong Kong Observatory Headquarters from 1885-2008. Results show that, over the past 124 years, the extreme daily minimum and maximum temperatures, as well as the length of the warm spell in Hong Kong, exhibit statistically significant long-term rising trends, while the length of the cold spell shows a statistically significant decreasing trend. the time-dependent return period analysis also indicated that the return period for daily minimum temperature at 4°c or lower lengthened considerably from 6 years in 1900 to over 150 years in 2000, while the return periods for daily maximum temperature reaching 35°c or above shortened drastically from 32 years in 1900 to 4.5 years in 2000. Past trends in extreme temperatures from selected weather stations in southern china from 1951-2004 were also assessed. Over 70% of the stations studied yielded a statistically significant rising trend in extreme daily minimum temperature, while the trend for extreme maximum temperatures was found to vary, with no significant trend established for the majority of stations.

关键词： extreme temperature long-term trend Hong Kong southern china

comparison of foot strike patterns of barefoot and minimally shod runners in a recreational road race

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Journal of Sport and Health Science 2014年第2期3卷 137-142,153+157页

作者： Peter larson Performance Health Spine and Sport therapy

Background:Previous studies of foot strike patterns of distance runners in road races have typically found that the overwhelming majority of shod runners initially contact the ground on the ***,none of these studies has attempted to quantify foot strike patterns of barefoot or minimally shod *** study classifies foot strike patterns of barefoot and minimally shod runners in a recreational road ***:High-speed video footage was obtained of 169 barefoot and 42 minimally shod distance runners at the 2011 New York city Barefoot *** strike patterns were classified for each runner,and frequencies of forefoot,midfoot,and rearfoot striking were compared between the barefoot and minimally shod ***:A total of 59.2%of barefoot runners were forefoot strikers,20.1%were midfoot strikers,and 20.7%were rearfoot *** minimally shod runners,33.3%were forefoot strikers,19.1%were midfoot strikers,and 47.6%were rearfoot *** strike distributions for barefoot and minimally shod runners were significantly different both from one another and from previously reported foot strike distributions of shod road ***:Foot strike patterns differ between barefoot and minimally shod runners,with forefoot striking being more common,and rearfoot striking less common in the barefoot group.

关键词： Barefoot Biomechanics Foot strike Gait Minimal shoes Running

Self-Healing concrete with crystalline Admixture——A Review

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Journal of Wuhan University of technology(Materials Science) 2019年第5期34卷 1143-1154页

作者： A Ravitheja Dr t chandra Sekhara Reddy Dr c Sashidhar JNtU college of Engineering AnantapurAPIndia civil Engineering GPR Engineering CollegeKurnoolAPIndia civil Engineering JNTU College of EngineeringAnantapurAPIndia

the scope of the present paper is to understand the effects of crystalline admixture on the selfhealing capacity of the cementitious composites. Previous studies were examined and a conclusion was drawn to the effect that different additives to crystalline admixture tend to improve self-healing of concrete for larger cracks. It is recommended that initial treatment with chemical admixture can stimulate and heal further cracks and it has the better repeatability trend in mixing with the concretes and mechanical recovery is possible even under repetitive preloading. Effective self-healing with chemical admixtures even under open-air exposure, leads to study the importance of a service ability design parameter including the maximum allowable crack width by repeatability analysis as a function of the exposure with the concept of sealable crack width.

关键词： crystalline admixture permeability reducer admixture cracking

Study of central Intensity Ratio of Seyfert Galaxies in Nearby Universe

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Research in Astronomy and Astrophysics 2023年第4期23卷 85-93页

作者： K.t.Vinod c.Baheeja S.Aswathy c.D.Ravikumar Department of Physics University of CalicutMalappuram-673635India Department of Physics Providence Women's CollegeCalicut-673009India

We use the recently discovered simple photometric parameter central Intensity Ratio(cIR)determined for a sample of 57 nearby(z<0.02)Seyfert galaxies to explore the central features of galaxies and their possible conne... 详细信息

We use the recently discovered simple photometric parameter central Intensity Ratio(cIR)determined for a sample of 57 nearby(zt galaxies to explore the central features of galaxies and their possible connection with galaxy *** sample of galaxies shows strong anti-correlation between cIR and mass of their central supermassive black holes(SMBHs).the SMBH masses of ellipticals are systematically higher for a given cIR value than those for lenticulars and spirals in the ***,the correlation between cIR and central velocity dispersion is *** appears less influenced by the excess flux produced by the central engine in these galaxies,when compared to spectroscopic parameters like velocity dispersion and OⅣflux,and proves to be a fast and reliable tool for estimating central SMBH mass.

关键词： Galaxy evolution-galaxies active-galaxies photometry-(galaxies:)quasars supermassive black holes-galaxies Seyfert

Phytotoxicity of cadmium on protein, proline and antioxidant enzyme activities in growing Arachis hypogaea L. seedlings

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Journal of Environmental Sciences 2008年第2期20卷 199-206页

作者： N Dinakar P c Nagajyothi S Suresh Y Udaykiran t Damodharam Department of Environmental Sciences Sri Venkateswara UniversityTirupatiAndhra Pradesh-517 502India.

Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. Seeds were exposed to 25, 50, and 100 μmol/L cdcl2 concentrations, for a period of 10, 15, 20 and 25 d. the extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. the higher concentration of cadmium （100 μmol/L） resulted （leaves and roots） total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. cadmium caused significant changes in the activity of antioxidative enzymes. contrastingly cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase （GR） 337.72%, 306.14%, superoxide disumutase （SOD） 688.56%, 381.72%, ascorbate peroxidase （APX） 226.47%, 252.14%, peroxidase （POD） 72.19%, 60.29% and catalase （cAt） 228.96%, 214.74% as compared to control. cadmium stress caused a significant increase in the rate of SOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations.

关键词： toxicological effects cadmium protein proline antioxidant enzymes

Oxidation of propane over substituted Keggin phosphomolybdate salts

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Journal of Natural Gas chemistry 2009年第3期18卷 319-324页

作者： t.Mazari c.Roch.Marchal S.Hocine N.Salhi c.Rabia Laboratoire de chimie du Gaz Naturel Faculté de ChimieUniversité des Sciences et de la Technologie Houari Boumediéne ILV-UMR 8180 cNRS-Université de Versailles-St Quentin-en-Yvelines Batiment Lavoisier45 avenue des Etats-Unis78035 Versailles CedexFrance

Ammonium salts, （NH4）6HPMo11MO40 （M = Ni, co, Fe）, have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9 ℃/min. they were characterized by BEt method, XRD, 31p NMR, UV-Vis and IR techniques. the catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 ℃/min.

关键词： propane oxidation propene acrolein polyoxometalates phosphomolybdate