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International journal of Digital earth 2018年第8期11卷 803-824页

作者： S.R.Phinn e.M.Kovacs c.M.Roelfsema R.F.canto c.j.collier L.j.McKenzie Remote Sensing Research centre School of Earth and Environmental SciencesUniversity of QueenslandSt LuciaAustralia centre for Tropical Water and TeRRAtic ecosystem Research(TropWATeR) James Cook UniversityCairnsAustralia

Seagrass meadows are at increasing risk of thermal stress and recent work has shown that water temperature around seagrass meadows could be used as an indicator for seagrass *** thermal data have not been linked to the thermal properties of seagrass *** work assessed the covariation between 20 in situ average daily temperature logger measurement sites in tropical seagrass meadows and satellite derived daytime SST(sea surface temperature)from the daytime MODIS and Landsat sensors along the Great Barrier Reef coast in *** significant(R2=0.787–0.939)positive covariations were found between in situ seagrass logger temperatures and MODIS SST temperature and Landsat sensor temperatures at all sites along the *** MODIS SST were consistently higher than in situ temperature at the majority of the sites,possibly due to the sensor’s larger pixel size and location offset from field *** thermal data were lower than field-measured SST,due to differences in measurement scales and *** refined significantly and tested over larger areas,this approach could be used to monitor seagrass health over large(106 km2)areas in a similar manner to using satellite SST for predicting thermal stress for corals.

关键词： Seagrass temperature thermal tolerance satellite sea surface temperature Landsat MODIS Great Barrier Reef

Using a systems modeling approach to improve soil management and soil quality

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Frontiers of Agricultural Science and engineering 2020年第3期7卷 289-295页

作者： enli WANG Di He Zhigan ZHAO chris j.smith Ben c.T.MAcDONALD cSIRO Agriculture and Food CanberraACT 2601Australia

Soils provide the structural support, water andnutrients for plants in nature and are considered to be thefoundation of agriculture production. Improving soilquality and soil health has been advocated as the goal ofsoil management toward sustainable agricultural intensifi-cation. There have been renewed efforts to define andquantify soil quality and soil health but establishing aconsensus on the key indicators remains difficult. It isargued that such difficulties are due to the former ways ofthinking in soil management which largely focus on soilproperties alone. A systems approach that treats soils as akey component of agricultural production systems ispromoted. It is argued that soil quality must be quantifiedin terms of crop productivity and impacts on ecosystemsservices that are also strongly driven by climate andmanagement interventions. A systems modeling approachcaptures the interactions among climate, soil, crops andmanagement, and their impacts on system performance,thus helping to quantify the value and quality of ***, three examples are presented to demonstrate this. Inthis systems context, soil management must be an integralpart of systems management practices that also includemanaging the crops and cropping systems under specificclimatic conditions, with cognizance of future climatechange.

关键词： APSIM available water capacity nitrogen management soil functional properties soil health soil-plant modeling

Recent Achievements in Developing Low Temperature and High Strain Rate Superplastic Materials

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journal of Materials Science & Technology 2001年第1期17卷 19-20页

作者： j.c Huang Inst.Materials Science and engineering Sun Yat-Son UniversityKaohsiungTaiwan 804China

This paper is to briefly outline our recent activities in developing low temperature or high strain rate superplastic materials, including aircraft-used and general-purpose Al- and Mg-base alloys or composites. as well as Ti3AI base intermetallic alloys. The processing routes applied included the thermomechanical treatment, equal channel angular pressing and other extrusion or forging methods.

关键词： High Strain Rate thermomechanical treatment intermetallic alloys processing routes high strain rate low temperature

A continental back-arc setting for the Namaqua belt:evidence from the Kakamas Domain

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Geoscience Frontiers 2022年第4期13卷 193-221页

作者： P.H.Macey R.j.Thomas A.F.M.Kisters j.F.A.Diener M.Angombe S.Doggart c.A.Groenewald c.W.Lambert j.A.Miller H.Minnaar H.smith H.F.G.Moen e.Muvangua A.Nguno G.Shifotoka j.Indongo D.Frei c.Spencer P.le Roux R.A.Armstrong c.Tinguely council for Geoscience P.O.Box 572BellvilleSouth Africa Department of Geology University of StellenboschSouth Africa Department of Geological Sciences University of Cape TownSouth Africa Geological Survey of Namibia WindhoekNamibia Department of Geology University of Free StateSouth Africa Department of earth Sciences University of the Western CapeSouth Africa The Institute of Geoscience Research Dept.Applied GeologyCurtin UniversityPerthAustralia Department of Geological Sciences and Geological engineering Queen’s UniversityKingstonCanada Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK RSeS Australian NationalUniversityCanberraACTAustralia

A study of the NW Kakamas Domain in South Africa/Namibia provides a new,unified lithostratigraphy and evolutionary history applicable to the whole Namaqua *** Mesoproterozoic history ranges from~1350 Ma to 960 Ma,but isotopic evidence suggests it was built upon pre-existing Paleoproterozoic continental crust that extended west from the Archaean *** eastern Namaqualand,early rift-related magmatism and sedimentation at~1350 Ma occurred in a confined ocean *** tectonic reversal and subduction at~1290–1240 Ma led to establishment of the Areachap,Konkiep and Kaaien *** the Kakamas Domain,widespread deposition of pelitic sediments occurred at~1220 Ma(Narries Group).These contain detrital zircons derived from proximal crust with ages between~2020 Ma and 1800 Ma(western Palaeoproterozoic domains)and 1350–1240 Ma(eastern early Namaqua domains),suggesting pre-sedimentation *** pelites underwent granulite grade metamorphism at~1210 Ma(peak conditions:4.5–6 kbar and 770–850°c),associated with voluminous,predominantly S-type granitoid orthogneisses between~1210 Ma and 1190 Ma(eendoorn and Ham River Suites)and low-angle ductile(D_(2))deformation which continued until~1110 Ma,interspersed with periods of *** enduring P-T regime is inconsistent with the expected crustal over-thickening associated with the generally-accepted collision-accretion Namaqualand ***,we propose the Namaqua Sector is a‘hot orogen’developed in a wide continental back-arc with subduction west of the present-day *** observed high geotherm resulted from thinned back-arc lithosphere accompanied by an influx of mantle-derived *** D_(2)deformation resulted from"bottom-driven"tectonics and viscous drag within the crust by convective flow in the underlying asthenospheric *** extended tectonothermal regime ceased at~1110 Ma when SW-directed thrusting stacked the Namaqua Domains into their current positions,constrained in

关键词： Kakamas Namaqua Geodynamics Geochronology Hot orogeny Mesoproterozoic

中国人头发纤维在UVA紫外光老化中的光谱学研究

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光谱学与光谱分析 2016年第6期36卷 1783-1788页

作者：唐颖 Gerald j.smith 北京工商大学北京市植物资源研究开发重点实验室北京100048 School of chemical and Physical Sciences Victoria University of Wellington

生活中,日光中的紫外辐射是导致头发光老化/光损伤的重要环境因素。长时间光照可使染发和天然发出现包括颜色褪变在内的退行性变化。以中老年人的自然灰发为样本来源,通过分离和人工漂染处理,获得了包括自然发色、漂白和染黑的六种头发... 详细信息

生活中,日光中的紫外辐射是导致头发光老化/光损伤的重要环境因素。长时间光照可使染发和天然发出现包括颜色褪变在内的退行性变化。以中老年人的自然灰发为样本来源,通过分离和人工漂染处理,获得了包括自然发色、漂白和染黑的六种头发类型,经过UVA（320～400nm）紫外光老化,采用漫反射光谱、三维荧光光谱和衰减全反射傅里叶变换红外光谱对头发纤维的老化特征进行无损分析,结合头发中光产生过氧化氢的定量分析,探讨了不同发色和漂染处理对头发耐光性的影响。结果表明,UVA辐照可通过Ⅱ型电子转移机制诱导头发中的光敏基团产生过氧化氢,导致纤维表面蛋白和色素分子的光氧化降解。自然发色与漂染发在光老化中的颜色变化不同：灰发和白发主要发生光黄化,人工染发和漂白发分别发生光褪色和光漂白。高湿度环境能加速头发的光降解。化学漂染处理会使头发中的光致过氧化氢水平升高,使纤维处于较高的氧化压力从而影响头发的光稳定性;而头发中的黑色素分子,包括天然黑色素和染发剂的人工黑色素,可能具有自由基产生与清除双重性。研究结果为建立中国人头发光损伤的光谱学评价方法和进一步研发针对国人发质的染护发产品提供了重要的实验基准数据。

关键词：头发纤维 UVA辐射漫反射光谱三维荧光光谱 ATR-FTIR 过氧化氢

Ultrastructural Alterations in Testes from Rats Treated with cysteine

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Biomedical and environmental Sciences 1993年第2期6卷 172-178页

作者： A.S.BeRNAccHI e.c.DeFeRReYRA c.R.DecASTRO j.A.cASTRO centro CentroCentroCentro de Investigaciones Toxicologicas(CEITOX)CITEFA/CONICETZufriategui4380(1603)Villa MartelliPcia.de Buenos AiresArgentina

cysteinc administration in relatively large doses has been repetitively employed as preventive agent against chemically induced cell injury or as *** this work we report that administration of a dose standard for those purposes(1.9gr/kg,po in water)causes significant ultrastructurally evident alterations in testcs at *** involves Scrtoli cells and *** found in the former include dilatation of nuclear membrane and of the smooth(SeR)and rough endoplasmic reliculum(ReR)and detachment of ribosomes from *** appeared more sparse and electron lucent than in controls and contained more lipid droplets and *** exhibited alterations in shape and *** in spermatids consisted of the appearance of irregular shape of the nucleus and alterations in their acrosomal *** was no histochemical evidence for either calcium accumulation or lipid peroxidation occurrence in testes of cysteine-trcated *** indicate that the large doses of cysteine employed in prevention of radiation or chemical effects is able to cause injury to Sertoli cells of the *** observed does not reach irreversible stages but may be sufficient to lead to production of abnormal spermatids.

关键词：抗辐射药半胱氨酸处理大鼠睾丸组织生精能力超微结构变化

effect of Pressure on Intermediate Valence States in cerium Kondo compounds

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journal of Rare earths 2004年第1期22卷 7-12页

作者： Oomi G Kagayama T smith j L Lacerda A H Kaji S Ohashi M Department of Physics Kyushu University Ropponmatsu Fukuoka 810-8560 Japan Department of Mechanical engineering and Materials Sciences Kumamoto University Kumamoto 860-8555 Japan Materials Science and Technology Los Alamos National Laboratory Los Alamos NM 87545 USA

electrical resistance, thermal expansion, lattice constants of the intermediate valence materials, α-ce and ceBe 13, were measured at high pressure. It is found that the Grüneisen parameters of Kondo temperature T K are 13 and 42 for α-ce and ceBe 13, respectively, and it decreases with increasing pressure. The magnetoresistance of α-ce shows H2 dependence and its coefficient increases with pressure below 1 GPa, but becomes nearly constant above 1 GPa. The results indicate that the intermediate valence states are enhanced at high pressure indicating the enhancement of hybridization between the 4f electron and conduction band.

关键词： condensel physics intermediate valence materials cerium rare earths

Gas Line Pressure Fluctuation Analysis of a Gas-Liquid Reactor

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journal of Thermal Science 2005年第3期14卷 267-271页

作者： j.j.j. cHeN j.c. ZHAO chemical & Materials engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand ProfessorChemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

关键词： gas liquid reactors bubble distribution signal analysis

effect of particle Froude number on sub-grid effective drag,filtered and residual stresses in fluidized gas-particle flows

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Particuology 2024年第12期95卷 36-48页

作者： christian c.Milioli Fernando e.Milioli Department of Mechanical engineering School of Engineering of São CarlosUniversity of São Paulo13566-590São CarlosSPBrazil

Sub-grid effective drag,filtered and residual stresses in the meso-scale of gas-particle fluidized flows are intrinsically affected by underlying micro-scale conditions as well as non-local effects related to macro-scale *** this work we applied microscopic two-fluid modeling to experiment with particle Froude number in order to evaluate the impact of this micro-scale condition over the concerning meso-scale derived sub-grid *** performed highly resolved simulations in periodic domains for particle Froude numbers from 12.21 to 799.22,for a wide range of macro-scale *** were filtered and classified by ranges of meso-scale markers for the various particle Froude *** particle Froude number was found to considerably affect the structural refinement of the heterogeneous flow fields thereby directly impacting effective drag,filtered and residual *** of those parameters showed systematic behaviors in relation to particle Froude number,thereby providing sound data for new sub-grid modeling propositions.

关键词： Fluidization Gas-particle flows Two-fluid model Sub-grid analysis Multiscale analysis

Stress waves propagation in solids under high-speed liquid impact

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 752-766页

作者： j.e.Field cavendish Laboratory Cambridge UniversityMadingly RoadCambridge CB3 0HEUK

An experiment of impact between 450 m/s water jets and polymethylme- thacrylate (PMMA) materials with complex surface geometry was conducted. The testing surfaces were a corner, step change, surface-breaking notch, inclined surface, etc. Stress waves propagation in the solid such as reflection, interference and diffraction was observed using polarized optics and an Imacon high speed camera (operating at both of 106 and 5×105 framing rates per second, fps). A damage test by the impact of the side jetting of an 850 m/s water jet was also carried out. It was found that stress waves propagation in solids depends not only on the surface geometry but also on the contact situation between liquid and solid. It was shown that the side jetting has sufficient damage potential although its head may consist of finer droplets. The results of this paper are useful to further analyze the dynamic stress state of solids under high-speed liquid impact.

关键词： high-speed liquid/solid impact, stress waves, mechanical property of solid, high-speed photography.