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Study on the Effect of Surface modification on the mechanical and Thermal Behaviour of Flax,Sisal and Glass Fiber

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Journal of Renewable materials 2019年第2期7卷 153-169页

作者： c.m.meenakshi A.Krishnamoorthy Department of mechanical Engineering Sathyabama Institute of Science and TechnologyChennaiTamil NaduIndia

Natural fiber-reinforced hybrid composites can be a better replacement for plastic composites since these plastic composites pose a serious threat to the *** aim of this study is to analyze the effect of surface modification of the natural fibers on the mechanical,thermal,hygrothermal,and water absorption behaviors of flax,sisal,and glass fiber-reinforced epoxy hybrid *** mechanical properties of alkaline treated sisal and flax fibers were found to increase ***,flexural and impact strength of glass/flax-fiber-reinforced hybrid samples improved by 58%,36%,and 51%,respectively,after surface alkaline *** addition,the hygrothermal analysis and water absorption capacity are studied and also the Interfacial bonding properties were analyzed using Scanning Electron microscopic *** thermal analysis using thermogravimetric analyzer reveals that the decomposition temperature for hybrid fiber reinforced composites are between 306 and 312℃.In conclusion,surface treatment improves the performance of natural fiber in hybrid fiber-reinforced composites,particularly flax fiber.

关键词： Hybrid composite surface treatments mechanical testing thermal analysis hygrothermal testing water absorption SEm analysiss

A Pathway to Explore the Hidden Specialty in the Design of Fifteen Level Inverter in Grid connected PV System

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computer modeling in Engineering & Sciences 2018年第6期115卷 359-386页

作者： c.Gopinath m.Rajvikram Department of Electrical and Electronics Engineering Sri Venkateswara College of Engineering(Autonomous)SriperumbudurTamilnaduIndia

This research paper proposes a single phase fifteen level inverter for a grid connected PV *** proposed inverter is also called cascaded asymmetric multilevel *** adopting appropriate hybrid modulation technique improved output voltage is obtained with minimum number of power electronic *** reducing the number of gate triggering circuits of the switches,the size and power consumption of the driving circuits can be *** total harmonic distortion of the output of the inverter is improved by this *** proposed inverter developed by cascading a full bridge inverter with modified H bridge multilevel *** validity of the proposed system is verified through mATLAB simulations.

关键词： Hybrid modulation multilevel inverter photo voltaic system grid connected inverter

consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz c.c.m.van de Wiel L.A.P.Lotz m.J.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency Plant products

Pancreatic ductal system obstruction and acute recurrent pancreatitis

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World Journal of Gastroenterology 2008年第7期14卷 1027-1033页

作者： m Delhaye c matos m Arvanitakis J Devière Department of Gastroenterology and Hepatopancreatology Erasme University HospitalBrusselsBelgium

Acute recurrent pancreatitis is a clinical entity largely associated with pancreatic ductal obstruction. This latter includes congenital variants, of which pancreas divisum is the most frequent but also controversial, chronic pancreatitis, tumors of the pancreaticobiliary junction and sphincter of Oddi dysfunction. This review summarizes current knowledge about diagnostic work-up and therapy of these conditions.

关键词： Pancreatitis congenital variants Sphincter of Oddi dysfunction Pancreatic tumors magnetic resonance cholangiopancreatography Endoscopic retrograde cholangiopancreatography

UV reflectance but no evidence for colour mimicry in a putative brood-deceptive orchid corybas cheesemanii

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current Zoology 2014年第1期60卷 104-113页

作者： m. m. KELLY A. c. GASKETT School of Biological Sciences The University of Auckland Private Bag 92019 Auckland 1142 New Zealand

Rewardless orchids attract pollinators by food, sexual, and brood-site mimicry, but other forms of sensory deception may also operate. Helmet orchids （corybas, Nematoceras and related genera） are often assumed to be brood-site deceivers that mimic the colours and scents of mushrooms to fool female fungus gnats （mycetophilidae） into attempting oviposition and polli- nating flowers. We sampled spectral reflectances and volatile odours of an endemic terrestrial New Zealand orchid corybas cheesemanii, and co-occurring wild mushrooms. The orchid is scentless to humans and SPmE Gc-mS analyses did not detect any odours, but more sensitive methods may be required. The orchids reflected strongly across all visible wavelengths （300-700nm） with peaks in the UV （-320nm）, yellow-green （500-600 nm） and red regions （650-700 nm）, whereas mushrooms and surrounding leaf litter reflected predominantly red and no UV. Rather than mimicking mushrooms, these orchids may attract pollinators by exploiting insects＇ strong sensory bias for UV. modelling spectral reflectances into a categorical fly vision model and a generic tetrachromat vision model provided very different results, but neither suggest any mimicry of mushrooms. However, these models require further assessment and data on fly spectral sensitivity to red wavelengths is lacking - a problem given the predominance of red, fly-pollinated flowers worldwide

关键词： Diptera colour space Fly pollination Orchidaceae Spectral reflectance Visual modelling

metallographic Analyses of Laser Gladded Wc-Ni and Wc-co Hard-facing metals

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材料热处理学报 2004年第05B期25卷 996-999页

作者： HK chikwanda m chiremba c Van Rooyen Department of chemical &metallurgical Engineering Tshwane University of Technology Pretoria South Africa.Department of Chemical &Metallurgical Engineering Tshwane University of Technology Pretoria South Africa.National Laser Centre CSIR Pretoria South Africa

Laser cladding is performed to improve the surface properties of metallic machine components. Extensive work is being conducted to investigate the relationships among the cladding parameters, clad powder characteristics and the quality of the clad layer. This work presents some of the metallographic analyses results of Wc -Ni and Wc-co clad layers. The clad layers are characterised with non-uniform carbide particles, mostly Wc imbedded in a more ductile matrix. The transition from the clad layer to the substrate metal had a distinct dilution zone. The ratio of this zone to the clad height was in the range of 10 -12% and this still needs to be refined.

关键词：激光包覆衬底合金包覆高度包覆深度 Wc-Ni Wc-co

Site Selective Excitation and Energy Transfer in LiKGdF_5 crystal co-doped with Er^(3+) and Tb (3+)

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Journal of Rare Earths 2004年第1期22卷 22-26页

作者：尹民 Khaidukov N m Krupa J c Structure Research Laboratory Kurnakov Institute of General and Inorganic chemistry Institut de Physique Nucléaire

crystals of LiKGdF 5∶Er 3+, Tb 3+ grown by the hydrothermal synthesis technique with concentrations of 2% and 0.4% were analysed. By using site selective excitation measured at low temperature, luminescence and excitation spectra from Er 3+ and Tb 3+ ions embedded in LiKGdF 5 were clearly separated. The lifetimes of the emitting levels 4S 3/2 of Er 3+ and 5D 4 of Tb 3+ were also determined. Following the site selective spectroscopy study, the dominant energy transfer process from Tb 3+ to Er 3+ in the crystal was then investigated via transient experiments.

关键词： optics condensed matter physics energy transfer luminescence LiKGdF 5∶Er3+, Tb3+ rare earths

Visualising data distributions with kernel density estimation and reduced chi-squared statistic

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Geoscience Frontiers 2017年第6期8卷 1247-1252页

作者： c.J.Spencer c.Yakymchuk m.Ghaznavi Earth Dynamics Research Group The Institute of Geoscience ResearchDepartment of Applied GeologyCurtin UniversityPerthAustralia Department of Earth and Environmental Sciences University of WaterlooWaterlooCanada David R.cheriton School of computer Science University of WaterlooWaterlooCanada

The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of numerical models that are used to visualize and interpret *** commonly used tools are the kernel density estimation and reduced chi-squared statistic used in combination with a weighted *** to the wide applicability of these tools,we present a Java-based computer application called KDX to facilitate the visualization of data and the utilization of these numerical tools.

关键词： Data visualisation Kernel density estimation Reduced chi-squared statistic mean square weighted deviation Geostatistics

A Grid middleware for Distributed Java computing with mPI Binding and Process migration Supports

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Journal of computer Science & Technology 2003年第4期18卷 505-514页

作者：陈琳王卓立 Francis c.m.Lau Department of computer Science and Information Systems The University of Hong Kong P.R. China

"Grid" computing has emerged as an important new research field. With years of efforts, grid researchers have successfully developed grid technologies including security solutions,resource management protocols, information query protocols, and data management services. However, as the ultimate goal of grid computing is to design an infrastructure which supports dynamic,cross-organizational resource sharing, there is a need of solutions for efficient and transparent task re-scheduling in the *** this research, a new grid middleware is proposed, called G-JavamPI. This middleware adds the parallel computing capability of Java to the grid with the support of a Grid-enabled message passing interface (mPI) for inter-process communication between Java processes executed at different grid points. A special feature of the proposed G-JavamPI is the support of Java process migration with post-migration message redirection. With these supports, it is possible to migrate executing Java process from site to site for continuous computation, if some site is scheduled to be turned down for system reconfiguration. moreover, the proposed G-JavamPI middleware is very portable since it requires no modification of underlying OS, Java virtual machine, and mPI package. Preliminary performance tests have been conducted. The proposed mechanisms have shown good migration efficiency in a simulated grid environment.

关键词： grid middleware mPI Java process migration