Liliane Nga¹, Benoit Ndiwe^1,2, Achille Bernard Biwolé¹, Antonio Pizzi^3,*, Jean Jalin Eyinga Biwole¹, Joseph Zobo Mfomo¹

Journal of Renewable Materials, Vol.12, No.3, pp. 553-568, 2024, DOI:10.32604/jrm.2023.046568

Abstract Extracts of plant origin, particularly tannins, are attracting growing interest for the sustainable development of materials in the industrial sector. The discovery of new tannins is therefore necessary. The 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 extracts. Yield by successive water extraction was 35%. MALDI-TOF/MS analysis… More >

PARSOTAM H. PARSANIA^1,*, JIGNESH V. PATEL², JIGNESH P. PATEL³

Journal of Polymer Materials, Vol.40, No.3-4, pp. 271-284, 2023, DOI:10.32381/JPM.2023.40.3-4.9

Abstract Bisphenol-C epoxy crotonate resin was synthesized by reacting 8.09g epoxy resin of bisphenolC, and 2.15g crotonic acid using 25 mL 1,4-dioxane as a solvent, and 1 mL triethylamine as a catalyst at reflux temperature for 1-6 h. Solid epoxy crotonate (ECCR) is highly soluble in common organic solvents. ECCR was characterized by its acid (24.5-1.5 mg KOH/g) and hydroxyl (504.5-678.4 mg KOH/g) values. The structure of ECCR is supported by FTIR and 1 HNMR spectroscopic methods. A DSC endothermic transition at 229o C indicated melting followed by thermal polymerization of ECCR. ECCR is thermally stable up to 320o C and… More >

Bengang Zhang^1,*, Antonio Pizzi^2,*, Mathieu Petrissans¹, Anelie Petrissans¹, Colin Baptiste¹

Journal of Renewable Materials, Vol.11, No.12, pp. 4097-4121, 2023, DOI:10.32604/jrm.2023.029761

Abstract 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 –NH₂ groups. A tannin-aminated tannin (ATT) particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-liking the two by substituting tannin’s hydroxyl groups with the –NH₂ groups on the aminated tannin to form –NH-bridges between the two. The resulting particleboard coating gave encouraging results when pressed at 180°C for 3 min. Conversely, the system in which tannin was reacted/cross-liked with urea (ATU) by a similar amination reaction… More >

Mianmo Meng^1,*, Wenming Ji²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.09159

Abstract Tight reservoirs hold a vast natural gas in Ordos Basin, and efficient development of these resources can offset the energy shortage. Due to the low-porosity and low-permeability, hydraulic fracturing becomes necessary to tap its resources. After fracturing, a large amount of fracturing fluid fills pore space near hydraulic fracture, which will influence the gas production. This study focused on the water occurrence of tight gas reservoirs and its influencing factors. Samples were selected from Upper Paleozoic Taiyuan and Shihezi Formations from Ordos Basin. The main experiments include porosity, permeability, mineral composition, nitrogen adsorption (NA), mercury intrusion porosimetry (MIP), nuclear magnetic… More >

Yue Liang, Wenxuan Dai, Wei Chen^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2639-2659, 2023, DOI:10.32604/fdmp.2023.027622

Abstract Glass powder of various particle sizes (2, 5, 10 and 15 μm) has been assessed as a possible cement substitute for mortars. Different replacement rates of cement (5%, 10%, 15%, and 20%) have been considered for all particle sizes. The accessible porosity, compressive strength, gas permeability and microstructure have been investigated accordingly. The results have shown that adding glass powder up to 20% has a significantly negative effect on the porosity and compressive strength of mortar. The compressive strength initially rises with a 5% replacement and then decreases. Similarly, the gas permeability of the mortar displays a non-monotonic behavior; first, it… More >

Elham Azadeh¹, Antonio Pizzi^1,2,*, Christine Gerardin-Charbonnier^1,*, Philippe Gerardin¹

Journal of Renewable Materials, Vol.11, No.6, pp. 2823-2848, 2023, DOI:10.32604/jrm.2023.027651

Abstract 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 involved. This 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 diamine. The 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 reactions. The carbohydrate skeleton of the hydrolysable tannin is also able… More > Graphic Abstract

Yiguo Chen^1,2,3,*, Congjun Feng^1,2, Yonghong He³, Zhijun Chen³, Xiaowei Fan³, Chao Wang³, Xinmin Ge⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 2451-2463, 2023, DOI:10.32604/cmes.2023.021145

Abstract The low-field nuclear magnetic resonance (NMR) technique has been used to probe the pore size distribution and the fluid composition in geophysical prospecting and related fields. However, the speed and accuracy of the existing numerical inversion methods are still challenging due to the ill-posed nature of the first kind Fredholm integral equation and the contamination of the noises. This paper proposes a novel inversion algorithm to accelerate the convergence and enhance the precision using empirical truncated singular value decompositions (TSVD) and the linearized Bregman iteration. The L1 penalty term is applied to construct the objective function, and then the linearized… More > Graphic Abstract

Wei Chen^1,*, Ao Xu¹, Hejun Zhang¹, Mingquan Sheng¹, Yue Liang¹, Frederic Skoczylas²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1623-1636, 2023, DOI:10.32604/fdmp.2023.025083

Abstract Two different freeze-thaw cycles (FTC) are considered in this study to assess the related impact on gas permeability and micro-pore structure of a mortar. These are the water-freezing/water-thawing (WF-WT) and the air-freezing/air-thawing (AF-AT) cycles. The problem is addressed experimentally through an advanced nuclear magnetic resonance (NMR) technique able to provide meaningful information on the relationships among gas permeability, pore structure, mechanical properties, and the number of cycles. It is shown that the mortar gas permeability increases with the number of FTCs, the increase factor being 20 and 12.83 after 40 cycles for the WF-WT and AF-AT, respectively. The results also… More >

Fulin Wang^*, Xinyang Geng, Zhengping Yuan, Shijiao Yang^*

Journal of Renewable Materials, Vol.11, No.3, pp. 1469-1484, 2023, DOI:10.32604/jrm.2022.024994

Abstract The use of some environmental functional minerals as backfill-modified materials may improve the leaching resistance of cemented uranium tailings backfill created from alkali-activated slag (CUTB), but these materials may participate in the hydration reaction of the cementitious materials, which could have a certain impact on the pore structure of the CUTB, thus affecting its mechanical properties and leaching resistance. In this paper, natural zeolite is selected as the backfill-modified material, and it is added to alkali-activated slag paste (AASP) and CUTB in cementitious material proportions of 4%, 8%, 12%, and 16% to prepare AASP mixtures and CUTB mixtures containing environmental… More >

Houda Saad^1,2,*, Antonio Pizzi^3,4, Bertrand Charrier², Naceur Ayed¹, Karsten Rode⁵, Fatima Charrier - El Bouhtoury²

Journal of Renewable Materials, Vol.3, No.1, pp. 34-43, 2015, DOI:10.7569/JRM.2014.634130

Abstract The possible use of Tunisian pomegranate tannins in wood adhesive formulation was studied for the fi rst time. Colorimetric tests, Fourier transformed infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and matrix-assisted laser desorption/ionization time-of-fl ight (MALDI-TOF) mass spectrometry were used to examine pomegranate tannins. Analysis showed that pomegranate peels are rich in hydrolyzable tannins. The Stiasny number tests showed the low reactivity of pomegranate tannin extract to formaldehyde and thus the diffi culty of using it in wood adhesive formulation. Thermomechanical analysis (TMA) and strength analysis of pomegranate tannin/hexamine-based resin showed weak bonding properties. More >