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Identification of Secondary Metabolites in Tunisian Tilia platyphyllos *** MALDI-TOF and GC-MS

Journal of Renewable Materials 2024年第4期12卷 827-842页

作者： Ayda Khadhri Mohamed Mendili Marwa Bannour-Scharinger Eric Masson Antonio Pizzi University of El-Manar II Faculty of SciencesPlantSoilEnvironment Interactions LaboratoryCampus AcademiaTunis2092Tunisia lermab University of Lorraine27 Rue Philippe SeguinEpinal88000France

This study is the first to evaluate the phytochemical content and biological properties of Tunisian *** Scop.A total of 23 compounds of essential oils were identified by gas chromatography-mass spectrometry(GC-MS)analysis of bracts and fruit *** results show that oxygenated monoterpenes were the dominant class of essential *** phenolic composition was investigated by matrix-assisted laser desorption/ionizationtime of flight(MALDI-TOF).The analysis showed that the chemical profiles of the ethanolic extracts of bracts and fruits are substantially *** highest polyphenol content was found in the ethanolic extracts of the fruits(7.65 mg gallic acid equivalents(GAE).g−1 on dry weight(DW).As for the antioxidant capacity,it was recorded in the essential oils of the fruits(IC_(50)=0.91 ***^(−1)).The results obtained showed that the antioxidant activity of the fruit essential oil was higher than that of the ethanol *** fruit essential oil was also found to have the highest reducing power(IC_(50)=0.67 ***^(−1)).In terms of iron-chelating power,fruit essential oil has the highest chelating power(IC_(50)=2.03 ***^(−1)).Compared to the ethanolic extract,the essential oil had the maximum antioxidant *** enzymatic activity of acetylcholinesterase(AChE)inhibition of the essential oil from *** bracts had the most potent inhibitory effect(IC_(50)=0.77 ***^(−1)),followed by the essential oil from the fruits(IC_(50)=0.95 ***^(−1)).The results suggest that *** can be used as a potential source of naturally occurring bioactive compounds and antioxidants.

关键词： T.platyphyllos antioxidant activity acetylcholinesterase inhibition essential oil MALDI-TOF GC-MS

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Color and Gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated Weathering

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Journal of Renewable Materials 2024年第2期12卷 305-323页

作者： Fatemeh Hassani Khorshidi Saeed Kazemi Najafi Farhood Najafi Antonio Pizzi Dick Sandberg Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyP.O.Box 16765-654TehranIran lermab University of LorraineBlvd des AiguillettesNancy54000France Wood Science and Engineering LuleåUniversity of TechnologySkellefteåSweden

The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin *** this purpose,the prepared coatings were applied to pine wood surfaces and weathered ***,color and gloss of the coatings were measured before and after the weathering *** emission scanning electron microscopy(FE-SEM)micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 *** magnetic resonance(13C-NMR)spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based *** calorimetric analysis(DSC)test revealed that the glass-transition temperature(Tg)of lignin nanoparticles modified with diethylenetriamine(DETA)was 112.8℃ and Tg of lignin nano-particles modified with ethylenediamine(EDA)was 102.5℃,which is lower than the Tg of un-modified lignin(114.6℃)and lignin modified with DETA(126.8℃)and lignin modified with EDA(131.3℃).The coatings modified with lignin nano-particles had a greater change in *** lignin nano-particles in the modified coating are trapping hydroxyl radicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodified polyurethane *** weathering test,the nano-lignin-based coating had a rougher surface with a lower contact angle(0.78°)compared to the unmodified polyurethane coating(0.85°).

关键词： Amination propylene carbonate lignin biopolymer polyurethane coating polyol UN SDG 13

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Natural Convection of a Power-Law Nanofluid in a Square Cavity with a Vertical Fin

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2091-2108页

作者： Amira M’hadbi Mohammed El Ganaoui Haïkel Ben Hamed Amenallah Guizani Khalid Chtaibi lermab Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTI Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law nanofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of nanofluids,composed of water and Al_(2)O_(3),TiO_(2),and Cu nanoparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the Rayleigh number(Ra=10^(4)-10^(6)),nanoparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).Streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing Rayleigh number,regardless of the nanoparticle type or nanofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu nanoparticle volume fractions compared to Al₂O₃and TiO₂.Moreover,the average Nusselt numbers for power-law nanofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of Rayleigh number Ra owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning nanofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%nanoparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer nanofluid non-Newtonian fluid natural convection

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Preparation of Environmentally Friendly Urea-Hexanediamine-Glyoxal(HUG)Resin Wood Adhesive

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Journal of Renewable Materials 2024年第2期12卷 235-244页

作者： Qianyu Zhang Shi Chen Long Cao Hong Lei Antonio Pizzi Xuedong Xi Guanben Du Yunnan Key Laboratory of Wood Adhesives and Glue Products College of Material Science and EngineeringSouthwest Forestry UniversityKunming650224China International Joint Research Center for Biomass Materials Southwest Forestry UniversityKunming650224China College of Chemical and Materials Engineering Zhejiang A&F UniversityHangzhou311300China lermab University of LorraineEpinal88000France

Using non-toxic,low-volatile glyoxal to completely replace formaldehyde for preparing urea-glyoxal(UG)resin adhesive is a hot research topic that could be of great interest for the wood ***,urea-glyoxal(UG)resins prepared by just using glyoxal instead of formaldehyde usually yields a lower degree of *** results in a poorer bonding performance and water resistance of UG resins.A good solution is to pre-react urea to preform polyurea molecules presenting already a certain degree of polymerization,and then to condense these with glyoxal to obtain a novel UG ***,in this present work,the urea was reacted with hexamethylene diamine to form a polyurea named HU,and then this was used to react it with different amounts of glyoxal to synthesize hexamethylenediamine-urea-glyoxal(HUG)polycondensation resins,and to use this for bonding *** results show that the glyoxal can well react with HU polyuria via addition and schiff base reaction,and also the HUG resin exhibits excellent bonding strength and water *** shear strength of the plywood bonded with this HUG at 160°C hot press temperature as high as 1.93 MPa,2.16 MPa and 1.61 MPa,respectively,which meets the requirement of the China national standard GB/T 9846-2015(≥0.7 MPa),and can be a good choice as a wood adhesive for industrial application.

关键词： Urea-glyoxal resin hexamethylene diamine wood adhesives water resistance

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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins

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Journal of Renewable Materials 2024年第3期12卷 397-425页

作者： Antonio Pizzi Marie-Pierre Laborie Zeki Candan lermab University of LorraineFaculty of SciencesBlvd des AiguillettesNancy54000France Chair of Forest Biomaterials Institute of Earth and Environmental SciencesUniversity of FreiburgFreiburgGermany Freiburg Materials Research Center Alberst Ludwig University of FreiburgFreiburg79104Germany Department of Forest Products Engineering Faculty of ForestryIstanbul UniversitySariyerIstanbul34473Turkey

Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based *** are a definite class of sustainable materials of the forestry *** have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several *** review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and *** constitutes a basic but essential summary of what is necessary to know of these sustainable *** doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.

关键词： Tannins flavonoids sources extraction methods analysis methods

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Matrix Assisted Laser Desorption Ionization Time of Flight(MALDI-TOF)-Mass Spectrometry and^(13)C-NMR-Identified New Compounds in Paraberlinia bifoliolata(Ekop-Beli)Bark Tannins

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Journal of Renewable Materials 2024年第3期12卷 553-568页

作者： Liliane Nga Benoit Ndiwe Achille Bernard Biwolé Antonio Pizzi Jean Jalin Eyinga Biwole Joseph Zobo Mfomo Laboratory of Forest Resources and Wood Valorization Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 1872DoualaCameroun Laboratory of Mechanics Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 2701DoualaCameroun Laboratory of Studies and Research on Wood Material(lermab) University of LorraineNancyFrance

Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial *** discovery of new tannins is therefore *** aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica *** by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of *** are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic *** identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion *** information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the *** analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.

关键词： Tannin Paraberlinia bifoliolata Central African wood species MALDI-TOF/MS 13C NMR bark extracts thermomechanical behaviour wood-binder

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Structural Elucidation of the Polymeric Condensed Tannins of Acacia nilotica Subspecies by ^(13)C NMR, MALDI-TOF and TMA as Sources of Bioadhesives

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Journal of Renewable Materials 2024年第7期12卷 1291-1310页

作者： Zeinab Osman Antonio Pizzi Bertrand Charrier Institute of Engineering Research and Materials Technology National Center for ResearchP.O.Box 2404KhartoumSudan ENSTIB-lermab University of Lorraine27 rue Philippe SeguinEpinal88000France Department of Materials Science and Engineering Institute of Analytical Sciences and Physico-Chemistry for the Environment and Materials-Xylomat(IPREM-UMR5254)University of Pau and the Adour RegionE2S UPPACNRSMont de Marsan40004France

Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood *** extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atﬁrst to compare their *** tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder *** solutions(47%)were tested by both MALDI ToF,*** thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different *** gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract ***,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,*** 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ***(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence ofﬂavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or *** revealed that the three types of tannins had high MOE at their initial pH(5).

关键词： Acacia nilotica condensed tannins procyanidins prodelphinidins 13C NMR MALDI-ToF

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Hydrolysable Chestnut Tannin Extract Chemical Complexity in Its Reactions for Non-Isocyanate Polyurethanes(NIPU)Foams

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Journal of Renewable Materials 2023年第6期11卷 2823-2848页

作者： Elham Azadeh Antonio Pizzi Christine Gerardin-Charbonnier Philippe Gerardin lermab Faculty of Science and TechnologyUniversity of LorraineVandoeuvre les Nancy54506France lermab University of LorraineEpinal88051France

Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions *** method is based on two main steps:the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene *** hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these *** carbohydrate skeleton of the hydrolysable tannin is also able to participate through its hydroxyl groups to the same two reactions rendering the whole molecular complex able to react to form *** analysis by Matrix-Assisted Laser Desorption Ionization(MALDI-TOF)mass spectrometry and 13C Nuclear Magnetic Resonance(13C NMR)to further investigate the reaction mechanisms involved revealed the unsuspected complexity of chestnut hydrolysable tannin,with different fragments reacting in different manners forming a hardened network of considerable *** the morphology and performance of these types of foams changes slightly with the change in the amount of glutaraldehyde and hexamine hardeners,the best performing foam formulation previously determined was scanned by SEM and analysed chemically for the structures formed.

关键词： Hydrolysable tannin chestnut tannin non-isocyanate bio polyurethanes NIPU MALDI-ToF ^(13)C NMR SEM bio-based materials

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Numerical Modeling and Technico-Economic Analysis of a Hybrid Energy Production System for Self-Consumption: Case of Rural Area in the Comoros

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Journal of Power and Energy Engineering 2024年第5期12卷 24-59页

作者： Fahad Maoulida Mohamed Aboudou Kassim Rabah Djedjig Ahmed Ihlal Mohammed El Ganaoui lermab Laboratory of Studies and Research on Wood Material IUT of Longwy University of Lorraine Cosnes-et-Romain Longwy France LEMA Energy and Applied Mechanics Laboratory Faculty of Sciences and Techniques University of Comoros Moroni Comoros IREMIS Institute University of Mayotte Mayotte France LMER Laboratory of Materials and Renewable Faculty of Sciences University Ibn Zohr BP Agadir Morocco

This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW photovoltaic solar panels, a converter, and storage batteries as the proposed sources. The main objective of this study is to conduct a detailed analysis and optimization of a hybrid diesel and renewable energy system to meet the electricity demand of a remote area village of 800 to 1500 inhabitants located in the north of Ngazidja Island in Comoros. The study uses the Hybrid Optimization Model for Electric Renewable (HOMER) Pro to conduct simulations and optimize the analysis using meteorological data from Comoros. The results show that hybrid combination is more profitable in terms of margin on economic cost with a less expensive investment. With a diesel cost of $1/L, an average wind speed of 5.09 m/s and a solar irradiation value of 6.14 kWh/m2/day, the system works well with a proportion of renewable energy production of 99.44% with an emission quantity of 1311.407 kg/year. 99.2% of the production comes from renewable sources with an estimated energy surplus of 2,125,344 kWh/year with the cost of electricity (COE) estimated at $0.18/kWh, presenting a cost-effective alternative compared to current market rates. These results present better optimization of the used hybrid energy system, satisfying energy demand and reducing the environmental impact.

关键词： Hybrid System Rural Area Electrification Comoros Techno-Economic Analysis PV-Wind-Diesel-Battery Meteorological Data HOMER Energy Pro

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Self-Cross-Linked Tannin-Aminated Tannin Surface Coatings for Particleboard

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Journal of Renewable Materials 2023年第12期11卷 4097-4121页

作者： Bengang Zhang Antonio Pizzi Mathieu Petrissans Anelie Petrissans Colin Baptiste lermab I.U.T.Hubert CurienUniversity of LorraineÉpinal88000France lermab-ENSTIB University of LorraineEpinal88000France

Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-linking the two by substituting tannin’s hydroxyl groups with the–NH_(2)groups on the aminated tannin to form–NH-bridges between the *** resulting particleboard coating gave encouraging results when pressed at 180℃for 3 ***,the system in which tannin was reacted/cross-liked with urea(ATU)by a similar amination reaction did not perform as well as the ATT system,and this even when a higher curing temperature and longer hot press time were *** particular its water repellence was worse probably due to the presence of urea and such a system with lower ***,substituting the tannin–OHs with the urea–NH_(2)groups appeared to also take *** gave better results than ATU as regards water repellence and mechanical resistance as shown by the cross cut *** ATT system was shown to be between 95%and 98%*** difference appeared to be due,by TMA analysis,to the much faster formation of the ATT hardened network leading to a better cross-linked polymer *** chemical species formed for both the ATT and ATU system were studied by MALDI ToF and CP MAS^(13)C NMR.

关键词： Biocoatings particleboard aminated tannin cross-linked tannin-aminated tannin tannin-urea cross links water repellence cross cut test MALDI ToF ^(13)C NMR

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