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Journal of Forestry Research 2016年第2期27卷 427-431页

作者： Seyedeh Masoumeh Hafezi Aliakbar Enayati Kazem Doost Hosseini Asghar Tarmian Sayed Ahmad Mirshokraii Department of wood and Paper Sciecne & technology Faculty of Natural Resources University of Tehran Chemistry Department Payame Nour University

We evaluated the potential use of amino silane coupling agent （SiNH） to improve physical and mechanical properties of UF-bonded wheat straw （Triticurn aestivum L.） poplar wood particleboard. We examined the effects of varied content of silane coupling agent content and ratios of straw to poplar wood particles on particleboard prop- erties. The ratios of straw to poplar wood particles were 100：0, 85：15, 70：30 and 55：45. Silane coupling agent content was tested at three levels, 0, 5 and 10 %. The experimental panels were tested for their mechanical strength, including modulus of elasticity （MOE）, modulus of rupture （MOR）, intemal bonding （IB） and physical properties according to procedures specified in DIN 68763 （Chipboard for special purposes in building construction： concepts, requirements, testing, 1982-03, 1982）. All board properties were improved by the addition of silane cou- pling agent. The use of poplar wood particles had a positive effect on the mechanical properties of wheat straw parti- cleboard but had a negative effect on physical properties （thickness swelling and water absorption）.

关键词： Wheat straw particleboard Poplar wood UFresin Silane coupling age

Response of colour and hygroscopic properties of Scots pine wood to thermal treatment

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Journal of Forestry Research 2013年第3期24卷 571-575页

作者： Vasiliki Kamperidou Ioannis Barboutis Vasileios Vasileiou Aristotle University of Thessaloniki Faculty of Forestry and Natural Environment Laboratory of Wood Products and Furniture Technology54124 Thessaloniki Greece

The effect of heat treatment on the surface colour and hygro- scopic properties of pine wood were investigated in this study. Boards of Scots pine wood （Pinus sylvestris L.） were subjected to thermal treatment at 200℃, for 4, 6, and 8 h. The change of equilibrium moisture content and density values of the specimens in order to facilitate the understand- ing of the treated material behavior. The colour parameters L＊ a＊ and b＊, used to depict the total colour change （dE） of wood surface, were shown to change proportionally to the treatment intensity. Moreover, swelling in the tangential and radial directions and absorption of the specimens ap- peared to be enhanced in great extent by the thermal treatment process. The mean value of swelling percentage in the tangential direction de- creased 10.26%, 17.22%, and 19.60% for specimens treated for 4, 6, and 8 h, respectively, referring to the final measurement after 72 h of immer- sion. In radial direction, mean value of swelling percentage decreased 19.56%, 32.75%, and 34.65% for treated for 4, 6 and 8 h, respectively, after 72 h immersion, which attests the decrease in swelling and im- provement in the hygroscopic behavior of Scots pine wood.

关键词： Colour Hygroscopic properties Modification Thermaltreatment Scots pine

Physical and Mechanical Properties of Eco-Friendly Composites Made from wood Dust and Recycled Polystyrene

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Journal of Renewable Materials 2022年第1期10卷 75-88页

作者： Dafni Foti Eleni E.Voulgaridou Sotirios Karastergiou Hamid R.Taghiyari Antonios N.Papadopoulos Department of Forestry and Natural Environment International Hellenic UniversityDramaGreece Department of Forestry Wood Sciences and DesignUniversity of ThessalyKarditsaGreece wood Science and technology Department Faculty of Materials Engineering&New TechnologiesShahid Rajaee Teacher Training UniversityTehranIran

The development of alternative wood composites based on the use of waste or recycled materials can be beneficial due to over exploitation of natural *** this frame,an option for the successful utilization of waste polystyrene which avoids environmental problems that formaldehyde adhesives cause and also reduces waste dis-posal,is its potential application as a binder for the production of value-added environmentally friendly and low cost wood *** types of panel were successfully made,consisting of wood dust and two recycled poly-styrene contents,namely,15%and 30%.Both physical properties,water absorption and thickness swelling,and mechanical properties,modulus of rupture,shear strength parallel in the plane of the board and glue line shear strength,were significantly improved as the recycled polystyrene content increased from 15%to 30%.Water absorption and thickness swelling after 24 h immersion in water were improved by 165%and 750%as the recycled polystyrene content increased from 15%to 30%.The magnitude of the improvement in mechanical properties however,was less pronounced than of the physical properties since modulus of rupture,shear strength parallel in the plane of the board and glue line shear strength were increased by 43.6%,50%and 61.5%,*** low viscosity of the recycled polystyrene caused more mobility inside the panel matrix and therefore,an improved penetration took place into adequate depth of the compressed dust *** is concluded that boards can be successfully produced using these waste raw materials,wood dust and recycled polystyrene in organic solvent as a binder,and therefore it can reduce waste disposal and provide cleaner production for the development of wood-based boards.

关键词： Cold pressing composites recycled polystyrene wood dust

Synthesis of ion imprinted polymers for selective recognition and separation of rare earth metals

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Journal of Rare Earths 2017年第2期35卷 177-186页

作者： Mashitah M.Yusoff Nik Rohani Nik Mostapa Md Shaheen Sarkar Tapan Kumar Biswas Md Lutfor Rahman Sazmal Effendi Arshad Mohd Sani Sarjadi Ajaykumar D.Kulkarni faculty of Industrial sciences and technology University Malaysia Pahang faculty of Science and Natural Resources Universiti Malaysia Sabah Department of Applied sciences MIT Academy of Engineering

Lanthanide-ion imprinted polymers（L-IIPs） were synthesized by stoichiometric amounts of rare earth ions and the cavities in the polymers were created for the corresponding lanthanide ions. The maximum sorption capacities were estimated to be 125.3, 126.5, 127.6, 128.2 and 129.1 mg/g for Pr, Nd, Sm, Eu and Gd, respectively at p H 6. In the selectivity study, the L-IIPs exhibited good selectivity to the specific rare earth ions in the presence of coexisting cations. The imprinting results were found to be excellent with some rare earth ions over other competitor rare earth ions with the same charges and close ionic radius.

关键词： ion-imprinted polymers rare earths separation adsorption lanthanide-ions

Analytical Modeling of a Multi-queue Nodes Network Router

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International Journal of Automation and computing 2011年第4期8卷 459-464页

作者： Hussein Al-Bahadili Jafar Ababneh Fadi Thabtah faculty of Information technology Petra University Amman Jordan faculty of Information technology and sciences World Islamic Sciences and Education University Amman Jordan faculty of Information technology Philadelphia University Amman Jordan

This paper presents the derivation of an analytical model for a multi-queue nodes network router, which is referred to as the multi-queue nodes （mQN） model. In this model, expressions are derived to calculate two performance metrics, namely, the queue node and system utilization factors. In order to demonstrate the flexibility and effectiveness of the mQN model in analyzing the performance of an mQN network router, two scenarios are performed. These scenarios investigated the variation of queue nodes and system utilization factors against queue nodes dropping probability for various system sizes and packets arrival routing probabilities. The performed scenarios demonstrated that the mQN analytical model is more flexible and effective when compared with experimental tests and computer simulations in assessing the performance of an mQN network router.

关键词： Congested networks network routers active queue managements multi-queue nodes (mQN) systems analytical model- ing utilization factor.

Proper Teleparallel Homothetic Vector Fields in General Cylindrically Symmetric Space-Times in Teleparallel Theory of Gravitation Using Diagonal Tetrads

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Communications in Theoretical Physics 2017年第11期67卷 611-616页

作者： Ghulam Shabbir Masoom Ali Shahani M.Amer Qureshi F.M.Mahomed faculty of Engineering sciences GIK Institute of Engineering Sciences and Technology School of Mathematics University of the Witwatersrand

In this paper we consider the most general form of non-static cylindrically symmetric space-times in order to study proper teleparallel homothetic vector fields using the direct integration technique and diagonal tetrads. This study also covers static cylindrically symmetric, Bianchi type I, non-static and static plane symmetric space-times as well. Here, we will only discuss the cases which do not fall in the category of static cylindrically symmetric, Bianchi type I, non-static and static plane symmetric space-times. From the above study we show that very special classes of the above space-times yield 6, 7 and 8 teleparallel homothetic vector fields with non-zero torsion.

关键词： proper teleparallcl homothetic vector field Weitzenbck geometry Torsion

Effects of newly devised plasma lice comb on human hair

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Plasma Science and technology 2019年第12期21卷 78-84页

作者： Lars TEN BOSCH Andreas HUBER Philipp SAUERBIER Robert KOHLER Georg AVRAMIDIS Wolfgang VIOL University of Applied sciences and Arts HAWK Faculty NVon-Ossietzky-Strasse 99/10037085 GottingenGermany Neaspec GmbH Eglfinger Weg 285540 Munich-HaarGermany wood Biology and wood Products Faculty of Forest Sciences and Forest EcologyUniversity of GoettingenBüsgenweg 437077 GottingenGermany

A plasma device was developed showing high potential for a pesticide-free treatment of pediculosis. As a first safety assessment of the device was presented earlier, this present paper focuses on the damage introduced to human hair during a plasma treatment for pediculosis control. Therefore, human hairs were treated repeatedly to assess the possible occurring damage developing with increasing treatment durations. To analyse the inflicted changes on human hair examinations using x-ray photoelectron spectroscopy(XPS/ESCA), scanning nearfield optical microscopy(SNOM) and scanning electron microscopy were conducted, to compare the modifications of surface chemistry and mechanical alterations. The investigations revealed a mild impact on the surface chemistry(XPS/SNOM), while more distinct morphological changes on the hair surface could be observed. The authors conclude that an effect of the plasma comb device on the hair during a real-life treatment is negligible, due to the very short contact times during a standard combing procedure for pediculosis control.

关键词： atmospheric pressure plasma dielectric barrier discharge pediculosis SEM SNOM ESCA XPS hair smoothing plasma based pest management

Effects of Selected Printing Parameters on the Fire Properties of 3D-Printed Neat Polylactic Acid(PLA)and wood/PLA Composites

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Journal of Renewable Materials 2021年第11期9卷 1883-1895页

作者： Nataša Knez Mirko Kariž Friderik Knez Nadir Ayrilmis Manja Kitek Kuzman Fire Laboratory and Fire Engineering Slovenian National Building and Civil Engineering InstituteLjubljanaSI-1000Slovenia Department of wood Science and technology Biotechnical FacultyUniversity of LjubljanaLjubljanaSI-1000Slovenia Department of wood Mechanics and technology Forestry FacultyIstanbul University-CerrahpasaIstanbul34473Turkey

The effects of selected printing parameters on the fire properties of additively produced composites from neat polylactic acid(PLA)and wood/PLA filaments were *** reaction to fire of the 3D-printed specimens was tested according to the ISO 5660-1 cone calorimeter test *** results showed that the properties of the specimens when exposed to fire were significantly affected by the incorporation of wood flour into the PLA *** was also interesting that PLA specimens had much better reactions to fire than the wood/PLA *** to ignition was found to be much longer in the 3D-printed PLA *** the maximal heat release rate was a little higher in the PLA than the wood/PLA specimens,the duration of HRR was longer for the wood/PLA *** initial mass of the specimens was smaller in the wood/PLA composites,but during the radiant heat exposure the mass typically decreased slower than in the PLA specimens.

关键词： Reaction to fire wood polylactic acid(PLA) filament 3D printer biocomposite

Classification of Spectra of Emission Line Stars Using Machine Learning Techniques

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International Journal of Automation and computing 2014年第3期11卷 265-273页

作者： Pavla Bromová Petr koda Jaroslav Vázn faculty of Information technology Brno University of Technology Astronomical Institute of the Academy of sciences of the Czech Republic

Advances in the technology of astronomical spectra acquisition have resulted in an enormous amount of data available in world-wide telescope archives. It is no longer feasible to analyze them using classical approaches, so a new astronomical discipline,astroinformatics, has emerged. We describe the initial experiments in the investigation of spectral line profiles of emission line stars using machine learning with attempt to automatically identify Be and B[e] stars spectra in large archives and classify their types in an automatic manner. Due to the size of spectra collections, the dimension reduction techniques based on wavelet transformation are studied as well. The result clearly justifies that machine learning is able to distinguish different shapes of line profiles even after drastic dimension reduction.

关键词： Be star stellar spectrum feature extraction dimension reduction discrete wavelet transform classification support vector machines(SVM) clustering.

Boosting hydrogen and chemicals production through ethanol electro-reforming on Pt-transition metal anodes

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Journal of Energy Chemistry 2022年第7期31卷 394-406,I0011页

作者： Alberto Rodríguez-Gómez Fernando Dorado Paula Sánchez Ana Raquel de la Osa Chemical Engineering Department Faculty of Chemical Sciences and TechnologyUniversity of Castilla-La Mancha

The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particular, the influence of the secondary metal on the electrochemical performance as well as on the product distribution was studied. For that purpose, Pt X/C electrocatalysts(where X corresponds to Cu, Co, Ni and Ru) were synthesized by the modified polyol method and tested in both half-cell and proton exchange membrane(PEM) cell configurations. Characterization results showed that incorporation of Ni and Co into the Pt matrix enhances the morphological properties of the material, providing smaller crystallite sizes, higher active surface areas and hence, better dispersion when comparing to Ru and Cu-based electrocatalysts. Ethanol oxidation reaction(EOR) was evaluated by cyclic, linear voltammetry and chronopotentiometry assays. Pt Co/C and Pt Ni/C exhibited the highest electrocatalytic activity at high polarization levels, which translate into an improvement of more than 30%(up to 1050 m A cm^(-2)) in the hydrogen production and chemical yields. On the other hand, Pt Ru/C results more advantageous for a lower potential interval(<0.85 V) promoting the acetic acid production despite sacrificing ethanol conversion. Pt Cu/C presented the lowest results in both electrochemical performance and product distribution. Such differences in the electrochemical performance can be rationalized in terms of the synergistic effect between both metals(particle size distribution, grade of dispersion and hydrophilic behavior), which demonstrate that the incorporation of a different secondary metal plays an essential role in the EOR development.

关键词： Ethanol electrochemical reforming Bimetallic anodic electrocatalysts PEM cell High current performance Hydrogen Chemicals production