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mechanism of Infrared Detection and Transduction by Beetle melanophila Acuminata In memory of Jerry Wolken

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Journal of Bionic Engineering 2011年第2期8卷 129-139页

作者： meir Israelowitz Jeong-ah Kwon Syed W. h. Rizvi Christoph Gille herb P. von Schroeder Biomimetics Technologies Inc. 191 Ellis Avenue Toronto Ontario M6S 2X4 Canada hillman Cancer Center Research Pavilion Floor 2 2.35 5117 Centre Avenue Pittsburgh PA 15213 USA Institute of Biochemistry CharitO Universiaitsmedizin Monbijourstr. 2 10117 Berlin Germany University of Toronto 399 Bathurst Street 2E Tolvnto ON M5T2SS Canada

The melanophila acuminata beetle is attracted to forest fires via a pair of infrared sensory organs composed of sensilla. Our histological work showed that each sensillum contains lipid layers surrounding a protein layer and a unique polysaccharide base that is associated with a neuron to each sensillum. Infrared microscopy showed that the protein region maximally absorbs infrared radiation at 3 ~tm wavelength and at 10 ~tm, which corresponds to the known radiation produced by forest fires at 3 ~tm. mathematical calculations showed that the physical properties of the sensilla are such that the expected temperature rise is insufficient for transduction of the infrared signal through mechanical means or as a thermal receptor as previously thought; hence the protein plays the pivotal role in perception of single photons and transmission of the signal within the sensilla.

关键词： sensory organs sensillum insect radiation fire

Large endoscopic mucosal resection for colorectal tumors exceeding 4 cm

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World Journal of Gastroenterology 2010年第5期16卷 588-595页

作者： Philippe ah Soune Charles ménard Ezzedine Salah Ariadne Desjeux Jean-Charles Grimaud marc Barthet Department of Gastroenterology Hpital NordChemin des Bourrely13915 Marseille cedex 20France

AIm:To evaluate the feasibility and the outcome of endoscopic mucosal resection(EmR)for large colorectal tumors exceeding 4 cm(LCRT)undergoing piecemeal resection. mEThODS:From January 2005 to April 2008,146 digestive tumors larger than 2 cm were removed with the EmR technique in our *** these,34 tumors were larger than 4 cm and piecemeal resection was carried out on 26 colorectal *** mean age of the patients was 71 *** mean follow-up duration was 12 mo. RESULTS:LCRTs were located in the rectum,left colon,transverse colon and right colon in 58%,15%, 4%and 23%of cases,*** were sessile tumors larger than 4 cm with a mean size of 4.9 cm (4-10 cm).According to the Paris classification,34%of the tumors were typeⅠs,58%typeⅡa,4%typeⅡb and 4%typeⅡ*** examination showed tubulous adenoma in 31%,tubulo-villous adenoma in 27%,villous adenoma in 42%,high-grade dysplasia in38%,in situ carcinoma in 19%of the cases and mucosal carcinoma(m2)in 8%of the *** two cases(7.7%)of procedural bleeding that occurred were managed endoscopically and one small perforation was treated with *** follow-up,recurrence of the tumor occurred in three patients(12%),three of whom received endoscopic treatment. CONCLUSION:EmR for tumors larger than 4 cm is a safe and effective procedure that could compete with endoscopic submucosal dissection,despite providing incomplete histological assessment.

关键词： Endoscopic mucosal resection Perforation Colorectal carcinoma Large polyps

Avoiding artefacts in microCT imaging of collagen scaffolds:Effect of phosphotungstic acid(PTA)-staining and crosslink density

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Bioactive materials 2022年第2期7卷 210-219页

作者： Kyung-ah Kwon Daniel V.Bax Jennifer h.shepherd Ruth E.Cameron Serena m.Best Cambridge Centre for medical materials Department of Materials Science and MetallurgyUniversity of CambridgeCambridgeUnited Kingdom School of Engineering University of LeicesterLeicesterUnited Kingdom

X-ray micro-computed tomography(μ-CT)can be used to provide both qualitative and quantitative information on the structure of three-dimensional(3D)bioactive *** performed in a dry state,μ-CT accurately reflects the structure of collagen-based scaffolds,but imaging in a wet state offers challenges with *** we have used phosphotungstic acid(PTA)as a contrast agent to visualise fully hydrated collagen scaffolds in a physiologically relevant environment.A systematic investigation was performed to understand the effects of PTA on the results of μ-CT imaging by varying sample processing variables such as crosslinking density,hydration medium and staining *** samples in 0.3% PTA solution overnight completely stained the samples and the treatment provided a successful route forμ-CT analysis of crosslinked ***,significant structural artefacts were observed for samples which were either non-crosslinked or had low levels of crosslinking,which had a heterogeneous interior architecture with collapsed pores at the scaffold *** work highlights the importance of optimising the choice of processing and staining conditions to ensure accurate visualisation for hydrated 3D collagen scaffolds in an aqueous medium.

关键词： microCT crosslinking qualitative

Inverse heat Transfer Problem of Thermal Contact Conductance Estimation in Periodically Contacting Surfaces

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Journal of Thermal Science 2009年第2期18卷 150-159页

作者： m.h.shojaeefard K.Goudarzi m.sh.mazidi Dept. of mechanical Engineering Iran University of Science and Technology

The problems involving periodic contacting surfaces have different practical applications. An inverse heat conductionproblem for estimating the periodic Thermal Contact Conductance (TCC) between one-dimensional, constantproperty contacting solids has been investigated with conjugate gradient method (CGm) of function *** method converges very rapidly and is not so sensitive to the measurement errors. The advantage of thepresent method is that no a priori information is needed on the variation of the unknown quantities, since the solutionautomatically determines the functional form over the specified domain. A simple, straight forward techniqueis utilized to solve the direct, sensitivity and adjoint problems, in order to overcome the difficulties associatedwith numerical methods. Two general classes of results, the results obtained by applying inexact simulatedmeasured data and the results obtained by using data taken from an actual experiment are presented. In addition,extrapolation method is applied to obtain actual results. Generally, the present method effectively improves theexact TCC when exact and inexact simulated measurements input to the analysis. Furthermore, the results obtainedwith CGm and the extrapolation results are in agreement and the little deviations can be negligible.

关键词： thermal contact inverse problem conjugates gradient method

Sorption of certain lanthanides by kieselguhr loaded with Cyanex 572 from sulfate medium

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Journal of Rare Earths 2020年第3期38卷 299-305页

作者： sh.sh.Emam m.S.Gasser N.E.El-hefny W.h.mahmoud h.F.aly hot Laboratories Centre Atomic Energy AuthorityCairo 13759Egypt Department of Chemistry Faculty of ScienceAin Shams UniversityCairoEgypt

Kieselguhr for chromatography was loaded with Cyanex 572 extractant and characterized using X-ray diffraction(XRF),scanning electron microscopy(SEm),Fourier transform infra-red(FT-IR),and thermal *** of some heavy lanthanides together with yttrium by the prepared kieselguhr/Cy-572 sorbent was investigated by batch experiment in terms of initial metal ions concentrations,volume to solid mass ratio(V/m),sulfuric acid concentration as well as *** sorption equilibrium of Cy-572 loaded kieselguhr was satisfactorily explained by the pseudo second-order kinetic model and Langmuir isotherm ***,the values of thermodynamic parameters △G°,△h°,and △S°at25℃of the studied metal ions show that the process is spontaneous and endothermic in nature.2.0 mol/L hNO3 is promising to desorb these metal ions.

关键词： Sorption Cyanex 572 Lanthanides Kieselguhr Sulfate medium Rare earths

Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： N.E.El-hefny m.S.Gasser sh.sh.Emam W.h.mahmoud h.F.aly hot Laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [mA·(hA)] for Y(III) or Dy(III) in both media.1.0 mol/L hCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both hCI and hNOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

Experimental and numerical study on plasma nitriding of AISI P20 mold steel

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International Journal of minerals,metallurgy and materials 2016年第9期23卷 1065-1075页

作者： N.Nayebpashaee h.Vafaeenezhad sh.Kheirandish m.Soltanieh materials Processing Simulation Laboratory(mPS-LAB) School of Materials and Metallurgical EngineeringIran University of Science and Technology(IUST) School of materials and metallurgical Engineering Iran University of Science and Technology(IUST)

In this study, plasma nitriding was used to fabricate a hard protective layer on AISI P20 steel, at three process temperatures（450℃, 500℃, and 550℃） and over a range of time periods（2.5, 5, 7.5, and 10 h）, and at a fixed gas N2：h2 ratio of 75vol%：25vol%. The morphology of samples was studied using optical microscopy and scanning electron microscopy, and the formed phase of each sample was determined by X-ray diffraction. The elemental depth profile was measured by energy dispersive X-ray spectroscopy, wavelength dispersive spectroscopy, and glow dispersive spectroscopy. The hardness profile of the samples was identified, and the microhardness profile from the surface to the sample center was recorded. The results show that ε-nitride is the dominant species after carrying out plasma nitriding in all strategies and that the plasma nitriding process improves the hardness up to more than three times. It is found that as the time and temperature of the process increase, the hardness and hardness depth of the diffusion zone considerably increase. Furthermore, artificial neural networks were used to predict the effects of operational parameters on the mechanical properties of plastic mold steel. The plasma temperature, running time of imposition, and target distance to the sample surface were all used as network inputs; Vickers hardness measurements were given as the output of the model. The model accurately reproduced the experimental outcomes under different operational conditions; therefore, it can be used in the effective simulation of the plasma nitriding process in AISI P20 steel.

关键词： tool steel plasma nitriding sputtering neural networks

Sustainable Furfural Biomass Feedstocks Electrooxidation toward Value-Added Furoic Acid with Energy-Saving h_(2) Fuel Production Using Pt-Decorated Co_(3)O_(4) Nanospheres

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Energy & Environmental materials 2024年第2期7卷 350-358页

作者： Talshyn Begildayeνa Jayaraman Theerthagiri Seung Jun Lee ahreum min Gyeong-ah Kim Siνakumar manickam myong Yong Choi Department of Chemistry(BK21 FOUR) Core-Facility Center for Photochemistry&NanomaterialsResearch Institute of Natural SciencesGyeongsang National UniversityJinju 52828South Korea Petroleum and Chemical Engineering Faculty of EngineeringUniversiti Teknologi BruneiJalan Tungku Link GadongBandar Seri Begawan BE1410Brunei Darussalam

here,furfural oxidation was performed to replace the kinetically sluggish O_(2)evolution reaction(OER).Pt-Co_(3)O_(4)nanospheres were developed via pulsed laser ablation in liquid(PLal)in a single step for the paired electrocatalysis of an h_(2)evolution reaction(hER)and furfural oxidation reaction(FOR).The FOR afforded a high furfural conversion(44.2%)with a major product of 2-furoic acid after a 2-h electrolysis at 1.55 V versus reversible hydrogen electrode in a 1.0-m KOh/50-mm furfural *** Pt-Co_(3)O_(4)electrode exhibited a small overpotential of 290 mV at 10 mA cm^(-2).As an anode and cathode in an electrolyzer system,the Pt-Co_(3)O_(4)electrocatalyst required only a small applied cell voltage of~1.83 V to deliver 10 mA cm^(-2),compared with that of the pure water electrolyzer(OER||hER,~1.99 V).This study simultaneously realized the integrated production of energy-saving h_(2)fuel at the cathode and 2-furoic acid at the anode.

关键词： biomass conversion electrochemical furfural oxidation overall water splitting Pt-Co_(3)O_(4)electrocatalyst pulsed laser ablation in liquid

Sliding Wear Behavior of a Grey Cast Iron Surface Remelted by TIG

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Journal of materials Science & Technology 2009年第5期25卷 622-628页

作者： h.mohamadzadeh h.Saghafian sh.Kheirandish Department of metallurgy and materials Engineering Iran University of Science and TechnologyTehranIran

The sliding wear behavior of a grey cast iron surface remelted by tungsten inert gas （TIG） was studied and compared with the unremelted one in the current work. To evaluate the wear behavior a Pin-on-Disk wear test machine was used. Pins which were prepared from the samples with the remelted layers of different thicknesses of 1.2, 1.8, 2.5 and 3 turn were worn on an AISID3 steel counterface having a hardness of 63hRC under the applied loads of 54, 76 and gg N at a constant sliding velocity of 0.45 m/s. Scanning electron microscopy （SEm） equipped with energy dispersive X-ray analysis （edS） and X-ray diffraction （XRD） techniques were used to characterize worn surface and subsurface and also wear debris obtained from the wear tests under different test conditions. Results showed that surface remelted grey cast iron have better wear properties for all applied normal loads in comparison with unremelted ones. microscopic studies on the worn surfaces and subsurfaces of samples revealed that dominant wear mechanism for surface remelted samples was mild oxidative, while it was severe for unremelted samples. Increasing remelted layer thickness and then forming grosser microstructure lead to a decline of wear properties, whereas lower thickness of remelted layer with finer microstructure due to having higher cooling rate through remelting process can withstand better against wear.

关键词： Grey cast Iron Surface remelted Tungsten inert gas (TIG) Wear