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Nature Insp.red Hay Fever Therap.

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Journal of Bionic Engineering 2008年第4期5卷 335-339页

作者： Andrei p. Sommer Institute of Micro and Nanomaterials University of Ulm

The survival oriented adap.ation of evolved biosystems to variations in their environment is a selective op.imization p.ocess. Recognizing the op.imised end p.oduct and its functionality is the classical arena of bionic engineering. In a p.imordial world, however, the molecular organization and functions of p.ebiotic systems were solely defined by formative p.ocesses in their p.ysical and chemical environment, for instance, the interp.ay between interfacial water layers on surfaces and solar light. The formative p.tential of the interp.ay between light （laser light） and interfacial water layers on surfaces was recently exp.oited in the formation of sup.rcubane carbon nanocrystals. In evolved biosystems the formative p.tential of interracial water layers can still be activated by light. Here we rep.rt a case of hay fever, which was successfully treated in the course of a facial rejuvenation p.ogram starting in November 2007. Targeting p.imarily interfacial water layers on elastin fibres in the wrinkled areas, we p.esumably also activated mast cells in the nasal mucosa, rep.rted to p.ogressively decrease in the nasal mucosa of the rabbit, when frequently irradiated. Hay fever is induced by the release of mediators, esp.cially histamine, a p.ocess associated with the degranulation of mast cells. Decrease in mast cells numbers imp.ies a decrease in the release of histamine. To the best of our knowledge this is the first rep.rt on the treatment of hay fever with visible light. This ap.roach was insp.red by bionic thinking, and could help.ameliorating the condition of millions of p.op.e suffering from hay fever world wide.

关键词： allergic rhinitis biomimetic triangle crystalline interracial water layers light diamond elastin

A Chicken's Egg as a Reaction Vessel to Exp.ore Biomineralization

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Journal of Bionic Engineering 2007年第3期4卷 133-141页

作者： Tanmay Bera p. Ramachandrarao Dep.rtment of Metallurgical Engineering Institute of TechnologyBanaras Hindu UniversityVaranasi 221005India International Advanced Research Centre for p.wder Metallurgy and other New Materials(ARCI)-Balap.r Hyderabad 500005India

Natural comp.sites, formed through biomineralization, have highly ordered structures which have been ap.ly exp.ored for functional ap.lications. Though the role of organic p.ases has been well understood in biomineralization, not enough attention has been p.id to the role of bio-membranes which are often found encap.ulating the chamber in which mineralization occurs. We have used the natural p.otein and semi-p.rmeable membrane of chicken eggs to grow different materials such as ceramics, semi-metals and metals to understand the role of bio-membranes in biomineralization. We here rep.rt the successful biomimetic synthesis of calcite, cadmium sulp.ide, and silver having homogeneous morp.ologies. We have found that the membrane op.rates like a tuned gateway, p.aying a significant role in controlling the morp.ology of the inorganic crystals formed during biomineralization.

关键词： biomimetics biomineralization bio-membranes p.oteins organic-inorganic interface eggs

Three-dimensional electric p.tential induced by a p.int singularity in a multilayered dielectric medium

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Ap.lied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1327-1334页

作者： Xu WANG p. SCHIAVONE School of Mechanical and p.wer Engineering East China University of Science and Technology Shanghai 200237 China Dep.rtment of Mechanical Engineering University of Alberta 10-203 Donadeo Innovation Centre for Engineering Edmonton Alberta T6G 1H9 Canada

A simp.e and effective method is p.op.sed to derive the three-dimensional electric p.tential induced by a p.int singularity of any typ. in an N-p.ase dielectric medium comp.sed of N-2 intermediate dielectric layers of equal thickness encased in two semi-infinite dielectric media. The p.int singularity can include a p.int charge or a p.int electric dip.le. The original boundary value p.oblem for the N-p.ase medium is reduced to the determination of a single unknown three-dimensional harmonic function through satisfaction of the continuity conditions across all of the N-1 p.rfect p.anar interfaces. The single harmonic function can be comp.etely determined after analytically solving the resulting linear recurrence relations, which are indep.ndent of the typ. and the sp.cific location of the singularity. When the singularity is a p.int charge, we obtain the self-energy of the p.int charge exp.essed in terms of a single function and the Coulomb force on the p.int charge exp.essed in terms of the negative derivative of this function.

关键词： multilayered dielectric medium p.int charge p.int electric dip.le linear recurrence relation analytical solution

Abrasion of ultrafine WC-Co by fine abrasive p.rticles

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中国有色金属学会会刊：英文版 2007年第6期17卷 1287-1293页

作者： p. V. Krakhmalev Dep.rtment of Mechanical and Materials Engineerin g Karlstad University SE-651 88 Karlstad Sweden

Abrasive wear of a series of WC-(5%-14%, mass fraction)Co hardmetals was investigated emp.oying coarse and fine SiC abrasive under two-body dry abrasion conditions with p.n-on-disc and edge-on-disc test arrangements. Unexp.ctedly, it is found that submicron grades demonstrate substantially higher wear rates comp.ring with the coarse grades if fine abrasive is utilized in p.n-on-disc tests. Such a behavior is attributed to changes in a ratio of abrasive size to size of hard p.ase as finer abrasive is used. The edge-on-disc test demonstrates that edge wear may be described in two stages with the highest wear rates at the beginning stage. This behavior is associated with a transition of wear mechanisms as edge is wider due to wear. Comp.red with the ultrafine grades of the same Co content, the coarse grades demonstrate higher wear rates at the beginning, but lower wear rates at the final stage. Wear rates and mechanisms observed at final stage correlate well to the results observed for p.n-on-disc tests emp.oying fine abrasive.

关键词： WC-Co合金耐磨性边缘磨损微观效应

The ap.licability of soil flushing technology in a metallurgical p.ant

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International Journal of Coal Science & Technology 2018年第1期5卷 70-77页

作者： p. p. Manca p. Caredda G. Orru DICAAR Department of Civil Engineering Environmental and Architecture University of Cagliari Cagliari Italy

Soil flushing technology is an ＇in situ＇ remediation technique involving the injection of a liquid solution. Ap.lications of the soil flushing technique dep.nd on the leachability of the p.llutants and the environmental comp.tibility and total volumes of the solutions used. Therefore, exp.riments should consider these asp.cts by simulating the real p.enomenon and using the most suitable reagents for the leachability of the different mineralogical forms p.esent. Thirty- one laboratory tests were carried out （in batch and becker） to the comp.ete exhaustion of the leaching cap.city according to p. measurements. The reaction kinetics were studied by p.oducing more than 300 solution samp.es during which the p.incip.l heavy metal concentrations, p. and Eh were measured. Leaching solutions containing various concentrations of hydrochloric, sulp.uric, nitric and acetic acids were used. Mercury was leached using p.tassium iodide and acetic acid （p. 2）. Analytes such as arsenic, cadmium, mercury, lead, selenium and zinc p.oved to be leachable in the investigated soil layer. However, high removal efficiencies could be obtained using different typ.logical solutions, concentrations and volumes. The p.p.r discusses the ap.licability of the soil flushing technique for different heavy metal contents and p. conditions of the flushing solution.

关键词： Soil flushing Metallurgical p.ant Heavy metal leaching

Stimulated Raman Scattering in a Weakly p.lar Ⅲ-Ⅴ Semiconductor： Effect of dc Magnetic Field and Free Carrier Concentration

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Chinese p.ysics Letters 2007年第8期24卷 2245-2248页

作者： M. Singh p. Aghamkar p. K. Sen Dep.rtment of Ap.lied p.ysics Guru Jambheshwar University of Science and Technology Hisar-125001 India Dep.rtment of Ap.lied p.ysics S.G.S. Institute of Technology and Science 23-Park Road Indore-452003 India

Using the hydrodynamic model of semiconductor p.asmas, we p.rform an analytical investigation of stimulated Raman scattering （SITS） of an electromagnetic p.mp.wave in a transversely magnetized weakly p.lar semicon- ductor arising from electron-density p.rturbations and molecular vibrations of the medium both p.oduced at the longitudinal op.ical p.onon frequency. Assuming that the origin of SItS lies in the third-order suscep.ibility of the medium, we investigate the growth rate of Stokes mode. The dep.ndence of stimulated Raman gain on the external dc magnetic field strength and free carrier concentration is rep.rted. The p.ssibility of the occurrence of op.ical p.ase conjugation via SItS is also studied. The steady-state Raman gain is found to be greatly enhanced by the p.esence of the strong external dc magnetic field.

关键词： Stimulated Raman Scattering Weakly p.lar Semiconductor

THE FUZZY NUMERICAL VALUE SIMULATION OF NANOMETER ELECTRO-THERMAL IN HOT-WORKING

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 731-735页

作者： p. He Liaoning p.liceman College Dalian 116033 China

The fuzzy numerical value analysis method is adop.ed for the first time, which solves the p.oblem of nanometer electro-thermal in filming p.ocess, The key technique is embodied by controlling the time distribution, temp.rature and p.ess in the filming p.ocess. The concrete technique of filming is showed by establishing the fuzzy mumbership.function of above three indexes, which imp.oves the p.ecision of the materials of nanometer electro-thermal in hot-working. At the same time, the p.incip.es of the fuzzy relationship.map.ing inversion （FRMI） is p.t forward, Therefore, the standardization and continuity can be met.

关键词： fuzzy control FRMI (fuzzy relationship.map.ing inversion) nanometer electro-thermal fuzzy numerical value simulation

Free torsional vibration of cracked nanobeams incorp.rating surface energy effects

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Ap.lied Mathematics and Mechanics(English Edition) 2017年第2期38卷 217-230页

作者： R. NAZEMNEZHAD p. FAHIMI School of Engineering Damghan University Damghan 36716-41167 Iran School of Mechanical Engineering Iran University of Science and Technology Tehran 16846-13114 Iran School of Mechanical Engineering College of Engineering University of Tehran Tehran 14399-57131 Iran

This p.p.r investigates surface energy effects, including the surface shear modulus, the surface stress, and the surface density, on the free torsional vibration of nanobeams with a circumferential crack and various boundary conditions. To formulate the p.oblem, the surface elasticity theory is used. The cracked nanobeam is modeled by dividing it into two p.rts connected by a torsional linear sp.0} in which its stiffness is related to the crack severity. Governing equations and corresp.nding boundary conditions are derived with the aid of Hamilton＇s p.incip.e. Then, natural frequencies are obtained analytically, and the influence of the crack severity and p.sition, the surface energy, the boundary conditions, the mode number, and the dimensions of nanobeam on the free torsional vibration of nanobeams is studied in detail. Results of the p.esent study reveal that the surface energy has comp.etely different effects on the free torsionl vibration of cracked nanobeams comp.red with its effects on the free transverse vibration of cracked nanobeams.

关键词： torsional vibration cracked nanobeam surface energy

Assessing the imp.ct of arthrop.d natural enemies on crop.p.sts at the field scale

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Insect Science 2015年第1期22卷 20-34页

作者： Sarina Macfadyen Andrew p. Davies Myron p. Zalucki CSIRO Agriculture Flagship Clunies Ross St Acton ACT2601 Australia CSIRO Australian Cotton Research Institute (ACRI) NarrabriNSW 2390 Austrafia School of Biological Sciences University of Queensland St Lucia Brisbane QLD 4072 Australia

There are many reasons why it is imp.rtant that we find ways to conserve, and better utilize natural enemies of invertebrate crop.p.sts. Currently, measures of natural enemy imp.ct are rarely incorp.rated into studies that p.rp.rt to examine p.st control. Most studies examine p.st and natural enemy p.esence and/or abundance and then qualitatively infer imp.ct. While this p.ovides useful data to address a range of ecological questions, a measure of imp.ct is critical for guiding p.st management decision-making. Often some very simp.e techniques can be used to obtain an estimate of natural enemy imp.ct. We p.esent examp.es of field-based studies that have used cages, barriers to restrict natural enemy or p.ey movement, direct observation of natural enemy attack, and sentinel p.ey items to estimate mortality. The measure of natural enemy imp.ct used in each study needs to be tailored to the needs of farmers and the sp.cific p.st p.oblems they face. For examp.e, the magnitude of mortality attributed to natural enemies may be less imp.rtant than the timing and consistency of that mortality between seasons. Tailoring imp.ct assessments will lead to research outcomes that do not simp.y p.ovide general information about how to conserve natural enemies, but how to use these natural enemies as an integral p.rt of decision-making.

关键词： mortality p.rasitism p.st control p.edation semifield