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Journal of earth Science 2012年第6期23卷 900-907页

作者： l Senthilnathan e P Nobi T Thangaradjou l Kannan Centre of Advanced Study in Marine Biology Faculty of Marine SciencesAnnamalai UniversityParangipettai-608502TamilnaduIndia

The present study was carried out to track the path of Vellar estuary over a period of 38 years （1970-2008） and also to detect the impact of tsunami on estuarine complex of the Vellar estuary. Visual interpretation techniques were employed by using muitispectral data of landsat TM （1991） and IrS-P6 lISS III （2004, 2006, and 2008） to delineate shoreline changes in the VeUar estuarine complex. results clearly revealed the changes that occurred along the estuarine path over the period, and severe erosion was noticed in the seaward side of the MGr Thittu and accretion, along the estuarine mouth. It is also visible that there is clear river path shift in the river course. Although the sandbar formation was seen with only little morphologic modification up to 2004, the Indian Ocean tsunami that struck this coast （26 December, 2004） distorted the sandbar of the Vellar estuarine mouth; however, the 2006 satel- lite images confirmed that the sandbar was formed again to its original structure as that of before the tsunami.

关键词： estuary geomorphology IrS-P6 lISS III shoreline tsunami India.

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Acta Metallurgica Sinica(english letters) 2013年第6期26卷 721-727页

作者： A.r.Khalifeh A.Dehghan e.Hajjari Department of Materials Science and engineering School of EngineeringShiraz University Department of Materials Science and engineering Faculty of EngineeringShahid Chamran University

In present work the weldings of an austenitic stainless steel （AISI 304l） and a ferritic carbon steel （St37） were conducted by tungsten inert gas （TIG） welding process using four different austenitic filler metals, namely er308l, er309l, er316l and er310. Microstructure characteristics and mechanical properties of the weldments were studied using optical and scanning electron microscopy, ferrit-ometry, hardness, tensile and impact tests. The ferrite number （_N-~） of the weldments made by different electrodes varies between 0.5 and 9.5. It was found that the increase in amount of delta ferrite in the microstructure of the weld metals, causes the decrease of the impact toughness of the weldments. It seems that using er309l and er316l electrodes can provide a good combination between the mechanical and metallurgical properties of the joint in AISI 304l/St37 dissimilar welding.

关键词： Ferrous alloys Joining Microstructure Mechanical properties electrode

review on high repetition rate and mass production of the cryogenic targets for laser IFe

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High Power laser Science and engineering 2017年第2期5卷 28-51页

作者： I.V.Aleksandrova e.r.Koresheva lebedev Physical Institute Russian Academy of SciencesMoscow119991Russia National research Nuclear University MePhl(Moscow engineering Physics Institute) Moscow115409Russia

In inertial fusion energy(IFe) research, a considerable attention has recently been focused on the issue of large target fabrication for MJ-class laser facilities. The ignition and high-gain target designs require a condensed uniform layer of hydrogen fuel on the inside of a spherical shell. In this report, we discuss the current status and further trends in the area of developing the layering techniques intended to produce ignition, and layering techniques proposed to high repetition rate and mass production of IFe targets.

关键词： free-standing and line-moving targets high-repetition-rate fuel supply inertial fusion energy target mass production

Disturbance cue communication is shaped by emitter diet and receiver background risk in Trinidadian guppies

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Current Zoology 2022年第4期68卷 433-440页

作者： Jack A Goldman Adam l Crane laurence e A Feyten emily Collins Grant e Brown Department of Biology Concordia University7141 Sherbrooke Street WestMontrealQCCanada H4B 1R6

In animal communication systems,individuals that detect a cue(i.e.,“receivers”)are often influenced by characteristics of the cue *** instance,in many species,receivers avoid chemical cues that are released by emitters experiencing *** chemical“disturbance cues”appear to benefit receivers by warning them about nearby danger,such as a predator’s *** the active ingredients in disturbance cues have been largely unexplored,by-products of metabolized protein are thought to play a role for some *** so,the content(quality)and volume(quantity)of the emitter’s diet should affect their disturbance cues,thus altering how receivers perceive the cues and *** Poecilia reticulata are a species known to discriminate among disturbance cues from different types of donors,but dietary variation has yet to be *** this study,we found evidence that diet quality and quantity can affect disturbance cues released by guppy emitters(i.e.,experimental“donors”).receivers discriminated between donor cue treatments,responding more strongly to cues from donors fed a protein-rich bloodworm diet(experiment 1),as well as an overall larger diet(experiment 2).We also found that receivers exposed to higher background risk were more sensitive to disturbance cue variation,with the strongest avoidance responses displayed by high-risk receivers toward disturbance cues from donors fed the high-quality ***,diet,and perhaps protein specifically,affects either the concentration or composition of disturbance cues released by *** variation may be important in information signaling in social species like the guppy.

关键词： alarm cues chemical cues diet quality diet quantity protein

A non-fluorinated mechanochemically robust volumetric superhydrophobic nanocomposite

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Journal of Materials Science & Technology 2021年第7期66卷 213-225页

作者： e.Vazirinasab G.Momen r.Jafari Department of Applied Sciences University of Quebec in Chicoutimi(UQAC)555boul.de I'universiteChicoutimiQuebecG7H 2B1Canada

The widespread use of water-repellent superhydrophobic surfaces is limited by the inherent fragility of their micro-and nanoscale roughness, which is prone to damage and degradation. Here, we report a non-fluorinated volumetric superhydrophobic nanocomposites that demonstrate mechanochemical robustness. The nanocomposites are produced through the addition of microscale diatomaceous earth and nanoscale fumed silica particles to high-temperature vulcanized silicone rubber. The water-repellency of the surface and bulk of nanocomposites having 120 phr of filler was determined based on the water contact angle and contact angle hysteresis. We compared the water-repellency of nanocomposites of differing diatomaceous earth to fumed silica mass ratios. Increasing the amount of diatomaceous earth enhanced the water-repellency of the nanocomposite surface, whereas an increased amount of fumed silica improved the water-repellency of the bulk material. Moreover, increasing the diatomaceous earth/fumed silica mass ratio improved the cross-linking density and hardness values of the *** being subjected to a range of mechanical durability tests, including sandpaper abrasion,knife scratching, tape peeling, water jet impact, and sandblasting, the nanocomposite maintained a water contact angle of 163. and contact angle hysteresis of 2°. When the water-repellency of the prepared nanocomposites eventually deteriorated, we restored their superhydrophobicity by removing the upper surface of the nanocomposite. This extraordinary robustness stems from the embedded low surface energy micro/nanostructures distributed throughout the nanocomposite. We also demonstrated the chemical stability, UV resistance, and self-cleaning abilities of the nanocomposite to illustrate the potential for real-life applications of this material.

关键词： Volumetric superhydrophobic Nanocomposite Diatomaceous earth Hierarchical micro/nanostructure Mechanical robustness Chemical stability Self-cleaning

reiterated homogenization of a laminate with imperfect contact:gain-enhancement of effective properties

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Applied Mathematics and Mechanics(english edition) 2018年第8期39卷 1119-1146页

作者： F.e.AlVAreZ-BOrGeS J.BrAVO-CASTIllerO M.e.CrUZ r.GUINOVArT-DIAZ l.D.PereZ-FerNANDeZ r.rODrIGUeZ-rAMOS F.J.SABINA Facultad de Matematica y Computacion Departamento de MatematicaUniversidad de La HabanaSan Lazaro y LHabana 4La HabanaCP 10400Cuba Departamento de Matematicas y Mecanica Universidad Nacional Autonoma de MexicoInstituto de Investigaciones en Matematicas Aplicadas y en Sistemas01000 CDMXAP 20-126M′exico Departamento de engenharia Mecanica Universidade Federal do Rio de JaneiroPolitecnica/COPPECaixa Postal 68503Rio de JaneiroRJCEP 21941-972Brasil Departamento de Matematica e estatistica Universidade Federal de PelotasCaixa Postal 354PelotasRio Grande do SulCEP 96010-900Brasil

A family of one-dimensional(1D) elliptic boundary-value problems with periodic and rapidly-oscillating piecewise-smooth coefficients is considered. The coefficients depend on the local or fast variables corresponding to two different structural scales. A finite number of imperfect contact conditions are analyzed at each of the scales. The reiterated homogenization method(rHM) is used to construct a formal asymptotic solution. The homogenized problem, the local problems, and the corresponding effective coefficients are obtained. A variational formulation is derived to obtain an estimate to prove the proximity between the solutions of the original problem and the homogenized problem. Numerical computations are used to illustrate both the convergence of the solutions and the gain of the effective properties of a three-scale heterogeneous 1D laminate with respect to their two-scale counterparts. The theoretical and practical ideas exposed here could be used to mathematically model multidimensional problems involving multiscale composite materials with imperfect contact at the interfaces.

关键词： reiterated homogenization method(rHM) imperfect contact variational formulation effective coefficient gain

A New Chinese Anurognathid Pterosaur and the evolution of Pterosaurian Tail lengths

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Acta Geologica Sinica(english edition) 2012年第6期86卷 1317-1325页

作者： lÜ Junchang David W.e.HONe Institute of Geology Chinese Academy of Geological Sciences School of Biology and environmental Sciences University College Dublin

A new anurognathid pterosaur specimen from the Middle Jurassic Tiaojishan Formation of Qinglong, northern Hebie Province is described. The new specimen is referred to Dendrorhynchoides, based on the general morphology of the skeleton, but it represents a new species, named here as Dendrorhynchoides mutoudengensis sp. nov.. It is characterized by the presence of short, robust and straight teeth, and bearing wing metacarpal approximately 40% of the length of humerus. The new specimen provides further osteological information for anurognathid pterosaurs, especially the presence of a relatively elongate tail.

关键词： Pterosauria rhamphothynchoids anurognathid Dendrorhynchoides mutoudengensis,pterodactyloids tail evolution.

Bringing Norwegian mine into world of bits and bytes——possibilities and pitfalls

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中国有色金属学会会刊：英文版 2005年第S1期15卷 262-265页

作者： S. l. ellefmo e. ludvigsen Department of Geology and Mineral resources engineering Norwegian University of Science and Technology NorwayDepartment of Geology and Mineral Resources Engineering Norwegian University of Science and Technology Norway

rana Gruber AS is a mining company situated in northern Norway, just south of the artic circle. The hematite/magnetite ore is low grade, steeply dipping and intensively folded. The company excavates about 1.2 million tonnes of ore annually. The mining method is sublevel stoping. The final products are a hematite concentrate and different magnetite-products. The bits and bytes based methods and systems implemented for production planning and controlling are presented in the paper. Focus is on geological modelling, utilisation of variations in the deposit and associated uncertainty accumulating throughout the value chain. The methods and systems enable the mining department in greater extent than before, to deliver fragmented ore according to the specifications given by the processing plant.

关键词： mining geological variations uncertainty

Microcracking Behaviour of a TiAl-base Alloy with Different Microstructures during Compression

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Journal of Materials Science & Technology 1998年第5期14卷 415-418页

作者： Zhang, WJ Chen, Gl evangelista, e Francesconi, l Univ Sci & Technol Beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Univ Ancona Dept Mech I-60131 Ancona Italy

The microcracking behaviour of TiAl-based alloys with the duplex and fully-lamellar microstructures was studied during compression. It was found that the fracture involves propagation of the existing microcracks and development of more new nuclei, instead of being a nucleation-controlled event. The lamellar interfaces, especially those having an angle of about 0 similar to 30 degrees C to the loading axis, were found to be the favourable nucleation sites. Microcrack nucleation is likely to be initiated by tensile normal stress concentrated on the lamellar interfaces.

关键词： Titanium alloys

emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITe-Nordic eMBl Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2