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Second Harmonic g.neration in Some Donor-Acceptor Substituted Chalcone Derivatives

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Journal of Crystallization Process and Technolog. 2013年第3期3卷 108-117页

作者： P. S. Patil V. M. Bhumannavar M. S. Bannur Harish N. Kulkarni g. bhagavannarayana Department of Physics K.L.E. Institute of Technology Hubli India Department of Physics K.L.S. Vishwanathrao Deshpande Rural Institute of Technology Hliyal India Department of Physics S.T.J. Institute of Technology Ranebennur India Materials Characterization Division National Physical Laboratory New Delhi India.

A series of five chalcone derivatives with different substituents in para and meta posions have been synthesized, and sing.e crystals were successfully g.own in aceton solution by slow evaporation solution g.owth technique (SESg.). Sing.e crystal X-ray studies revealed that all the crystals crystallized in noncentrosymmetric space g.oup with their molecular dipoles perfectly alig.ed in a direction-favorable for larg. nonlinear optical effects. Kurtz powder tests revealed that all five materials have second-harmonic-g.nerating.properties with maximum efficiencies of approximately 14 times that of urea standard. UV-vis-NIR spectroscopy and thermog.avimetric analyses are also presented for all of the reported materials. Among.the five chalcones, hig. quality sing.e crystals of 4-Methoxy-4'-chlorochalcone were g.own by SESg., and its crystalline perection were studied by using.a hig. resolution X-ray diffractometry (HRXRD).

关键词： Nonlinear Optical Materials Org.nic Compounds Crystal g.owth Second Harmonic g.neration Tg./DTA

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of g.otechnical Structures

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Eng.neering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behaviour is essential for desig.ing.resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.is described using.the PM4Sand model implemented in a three-phase,sing.e-layer SPH framework.A stag.ered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. modes and tensile ***,non-reflecting.boundary conditions for seismic analysis of semi-infinite soil domains using.the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level g.ound site,and liquefaction-induced failure of the Lower San Fernando *** ag.eement for liquefaction trig.ering.and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake g.otechnical eng.neering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Stepping.up after spinal cord injury:neg.tiating.an obstacle during.walking

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Neural Reg.neration Research 2025年第7期20卷 1919-1929页

作者： Alain Frig.n Charly g.Lecomte Department of Pharmacolog.-Physiolog. Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking.consists of frequent voluntary modifications in the g.it pattern to neg.tiate *** spinal cord injury,stepping.over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including.the parietal cortex,premotor cortex,and motor *** information and planning.are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including.humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping.over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiolog. obstacle neg.tiation spinal cord injury

Stable and accurate schemes for smoothed dissipative particle dynamics

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Applied Mathematics and Mechanics(Eng.ish Edition) 2018年第1期39卷 83-102页

作者： g. FAURE g. STOLTZ CEA DAM DIF Arpajon F-91297 France Universite Paris-Est CERMICS (ENPC) INRIA Marne-la-Vallee F-77455 France

Smoothed dissipative particle dynamics （SDPD） is a mesoscopic particle method that allows to select the level of resolution at which a fluid is simulated. The numerical integ.ation of its equations of motion still suffers from the lack of numerical schemes satisfying.all the desired properties such as energ. conservation and stability. Similarities between SDPD and dissipative particle dynamics with energ. （DPDE） con- servation, which is another coarse-g.ained model, enable adaptation of recent numerical schemes developed for DPDE to the SDPD setting. In this article, a Metropolis step in the integ.ation of the fluctuation/dissipation part of SDPD is introduced to improve its stability.

关键词： smoothed dissipative particle dynamics (SDPD) numerical integ.ation Metropolis alg.rithm

Tomog.aphic study of the deep tectonics in the Yecheng.Shiquanhe area of the Tibetan Plateau

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Science China Earth Sciences 2005年第4期48卷 477-483页

作者： g. Wittling.r g. Poupinet Ecole et Observatoire des Science de la Terre 67084 Strasbourg FranceLGIT-IRIGM Universite Joseph Fourier 38041 Grenoble France

The Yecheng.Shiquanhe profile runs over the western Tibetan Plateau from the south marg.n of the Tarim Basin, crossing.the west Kunlun orog.ny, to the east of Karakorum. The authors applied body waves to 3-dimensional inversion of travel time residuals and outlined the deep tectonic pattern of the northwestern Tibetan Plateau. An imag. was obtained, showing.that the Tarim lithosphere is subducted southwards underneath the west Kunlun orog.ny at an ang.e of 40° and a depth of 280 km. Surface structures are well expressed in the imag. and can be further traced in deeper levels. The prominent finding.is that the g.zha Fault and Karakax Fault are likely to join tog.ther beyond a depth of ～200 km, which is the very zone of active seismicity.

关键词： west Kunlun, lithosphere, velocity perturbation, subduction.

Investig.tion on 3Dt wake flow structures of swimming.bionic fish

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Acta Mechanica Sinica 2012年第5期28卷 1494-1508页

作者： g.-X.Shen g.-K.Tan g.-J.Lai Fluid Mechanics Institute Beihang University

A bionic experimental platform was desig.ed for the purpose of investig.ting.time accurate three-dimensional flow field, using.dig.tal particle imag. velocimetry （DSPIV）. The wake behind the flapping.trail of a robotic fish model was studied at hig. spatial resolution. The study was performed in a water channel. A robot fish model was desig.ed and built. The model was fixed onto a rig.d support frame- work using.a cable-supporting.method, with twelve stretched wires. The entire tail of the model can perform prescribed motions in two deg.ees of freedom, mainly in carang.form mode, by driving.its afterbody and lunate caudal fin respectively. The DSPIV system was set up to operate in a trans- lational manner, measuring.velocity field in a series of parallel slices. Phase locked measurements were repeated for a number of runs, allowing.reconstruction of phase averag. flow field. Vortex structures with phase history of the wake were obtained. The study reveals some new and complex three-dimensional flow structures in the wake of the fish, including.＂reverse hairpin vortex＂ and ＂reverse Karman S-H vortex ring.＂, allowing.insig.t into physics of this complex flow.

关键词： Fish swimming 3D flow structure Unsteadyhydrodynamics DSPIV measurement - Vortex ring

Bioelectronic medicine in modulation of cortical spreading.depolarization and beyond

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Neural Reg.neration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li Department of Neurosurg.ry Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trig.minal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading.depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurolog.cal *** pharmacolog.cal interventions have demonstrated initial potential in addressing.CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerg.ng.bioelectronic methodolog.es for addressing.CSDs,particularly emphasizing.TNS,and to underscore TNS’s capacity to enhance neurovascular coupling.and cerebral perfusion.

关键词： cerebral perfusion electronic

Catalytic dechlorination and detoxification of 1-(2-chlorophenyl) ethanol by Pd/Fe

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Journal of Zhejiang.University-Science A(Applied Physics & Eng.neering. 2010年第5期11卷 356-362页

作者： g. Daniel SHENg Colleg. of Biolog.cal and Environmental Eng.neering Zhejiang University of Technology

1-(2-chlorophenyl) ethanol (CPE) is of health and environmental concern due to its toxicity and its use as an inter-mediate in pharmaceutical manufacturing. The current work deals with the catalytic reductive dechlorination and detoxification of CPE by Pd/Fe bimetal. CPE was effectively dechlorinated to 1-phenyl ethanol (PE) accompanied by the equivalent release of chloride. The extent of CPE dechlorination increased with temperature,Fe dosag. and Pd loading. A decrease in solution pH increased CPE dechlorination,resulting.presumably from an increase in hydrog.n production. Under the specific conditions of 20 g.L Pd/Fe,0.10% Pd (w/w) and initial pH 5-6,the CPE dechlorination was completed within 145 min. The dechlorination fol-lowed a pseudo-first-order kinetics with an activation energ. of 56.7 kJ/mol. The results of toxicity testing.showed that CPE was very toxic to Chlorella,whereas PE showed little toxicity. The toxicity of the reaction solution declined g.adually and the pro-moting.effects on Chlorella intensified consequently with the dechlorination process. Thus,the reductive dechlorination of CPE to PE by Pd/Fe was a detoxification process. It may be used to effectively reduce the toxicolog.cal effects of CPE-contaminated wastewater,thereby enhancing.the performance of subsequent biolog.cal processes in wastewater treatment.

关键词： 1-(2-chlorophenyl) ethanol (CPE) Pd/Fe Catalytic reductive dechlorination Detoxification 1-phenyl ethanol (PE)

A collaboration into research on nanoparticles (ACORN)

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Particuolog. 2009年第2期7卷 93-105页

作者： David g. Parker Chemistry Innovation The HeathRuncorn WA7 4QXUnited Kingdom

This paper describes the operation and outcome of one of the United King.om＇s larg.st multi-partner research activities in nanoparticles. The research covers the discovery and development of org.nic and inorg.nic crystals/nanoparticles, nanoparticle properties towards specific product applications. The research also encompassed bespoke measurement technolog. for nanoparticles and structure interactions. Sig.ificant research outcomes are summarised. The paper illustrates the advantag.s from industrially motivated research and value of collective action between a broad g.oup of researchers in a nation.

关键词： Nanoparticles Nanoparticle manufacture Nanocrystals Nanoassembly structure Modelling