Medjda Amari¹, Kamel Khimeche^1,*, Abdelkader Hima² , Redouane Chebout³, Abderahmane Mezroua¹

Journal of Renewable Materials, Vol.9, No.3, pp. 463-475, 2021, DOI:10.32604/jrm.2021.013680

Abstract Recently, the exploitation of renewable plant resources in the formulation of adhesives is very promising for their availability at low coast, as well as their richness in biomolecules such as polyphenols. In this way, many research studies tannins extracted from different sources such as mimosa, quebracho, and pine have been the subject of very satisfactory recent studies. In this paper, a new complete characterization of the tannins extracted from the bark of eucalyptus globulus harvested from two regions in Algeria was achieved. The structural characterization enabled us to confirm the richness in condensed tannins, particularly in procyanidin and prodelphinidin units.… More >

Cheng Cheng^1,2,*, Weiwei Sun², Bo Hu³, Guixiang Tao², Chao Peng², Yanjuan Tian⁴, Shujuan Wu^4,5

Journal of Renewable Materials, Vol.8, No.10, pp. 1243-1255, 2020, DOI:10.32604/jrm.2020.012054

Abstract The use of lignin, which is a by-product of the pulp and paper industry, in the development of asphalt binders would contribute to waste reduction, providing environmental, economic, and social benefits. In this study, samples of lignin-modified asphalt binder samples with different content of lignin (3%, 6%, 9%, 12%, and 15%) and unmodified asphalt (control) were tested using Fourier transform infrared spectroscopy (FTIR), dynamic shear rheometer (DSR), and thermogravimetry. The mechanism and effectiveness of lignin in improving the thermal stability of asphalt at high temperatures were analyzed. The FTIR analysis shows that no new characteristic absorption peak is seen in… More >

Dragomir Vassilev^1,*, Nadezhda Petkova², Yulian Tumbarski³, Milena Koleva¹, Panteley Denev²

Journal of Renewable Materials, Vol.8, No.6, pp. 675-686, 2020, DOI:10.32604/jrm.2020.09279

Abstract Undenicylic acid (10:1) is known as an antifungal agent and an active ingredient of many topical medicines [1–6]. The present research investigates the preparation of aliphatic esters of 10-undecylic acid with butanol and i-amyl alcohol by the conventional and ultrasound-assisted syntheses as well as the structural elucidation of the resulting compounds, by FTIR and NMR spectroscopy. The antimicrobial properties of the obtained 10-undecylenic esters were tested against Gram-positive bacteria (Staphylococcus aureus; Enterococcus faecalis; Listeria monocytogenes), Gram-negative bacteria (Escherichia coli; Salmonella sp.) and filamentous fungi (Penicillium sp.; Aspergillus niger; Fusarium moniliforme) using the conventional agar-well diffusion assay. The results demonstrated that… More >

Nadezhda Petkova^1,*, Radka Arabadzhieva¹, Dragomir Vassilev², Gergana Gencheva¹, Yulian Tumbarski³, Tsveteslava Ignatova-Ivanova⁴, Sevginar Ibryamova⁴, Mina Todorova¹, Milena Koleva², Panteley Denev¹

Journal of Renewable Materials, Vol.8, No.4, pp. 365-381, 2020, DOI:10.32604/jrm.2020.09292

Abstract Microwave-assisted irradiation was performed for esterification of chicory inulin with high degree of polymerization with acetic anhydride without a solvent only with a catalyst. The resulting esters were characterized by melting point, hydrophilic-lipophilic balance, thin-layer chromatography, ultraviolet spectroscopy, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Inulin acetate demonstrated a high degree of acetylation (2.5–3.0) and presented a white, water-insoluble substance with bitter taste. The FTIR and NMR spectra confirmed esterification and demonstrated the incorporation of hydrophobic residue to the water soluble inulin backbone. Swelling capacity, water holding, oil-holding capacities, the foamability, foam stability and emulsifying properties… More >

Qin Liu^*, Ruliang Zhang

Energy Engineering, Vol.117, No.2, pp. 89-98, 2020, DOI:10.32604/EE.2020.010373

Abstract With the development of urbanization in China, the problem of garbage disposal has become increasingly serious. Among the existing waste treatment technologies, pyrolysis is an emerging treatment technology, which has obvious advantages in terms of reduction and secondary pollution. It has good development prospects. This article first compares the advantages and disadvantages of various existing waste treatment technologies, and proposes an organization method that combines thermogravimetric analysis, kinetic analysis, tube furnace experiments, and domestic waste pyrolysis and low-calorie heat the decomposed gases burn together. Urban garbage is one of the main pollution sources of modern urban environmental pollution in the… More >

F.J. Santiago-Medina¹, M.C. Basso¹, A. Pizzi^1,2,*, L. Delmotte³

Journal of Renewable Materials, Vol.6, No.4, pp. 413-425, 2018, DOI:10.7569/JRM.2017.634172

Abstract The reaction of a desulphurized kraft lignin with hexamethylene diamine and dimethyl carbonate has allowed the development of isocyanate-free polyurethane resins. The present research work is based on previous studies made with hydrolyzable and condensed tannins, but takes advantage of the higher number of hydroxyl groups present in lignin and their different aliphatic and aromatic character. The obtained materials were analyzed by Fourier transform infrared (FTIR) spectroscopy, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and solid-state cross-polarization/magic angle spinning (CP MAS) 13 C nuclear magnetic resonance (NMR), which have revealed the presence of urethane functions. The interpretation of the… More >

F. J. Santiago-Medina¹, A. Pizzi^{1, 2*}, M. C. Basso¹, L. Delmotte³, S. Abdalla²

Journal of Renewable Materials, Vol.5, No.5, pp. 388-399, 2017, DOI:10.7569/JRM.2017.634142

Abstract The reaction of a desulphurized kraft lignin with hexamethylene diamine as a model of a polyamine has been investigated. For this purpose, guaiacol was also used as a lignin model compound and treated under similar conditions. Solid state CP-MAS 13C NMR, FTIR and MALDI-TOF spectroscopy studies revealed that polycondensation compounds leading to resins were obtained by the reaction of the amines with the phenolic and aliphatic hydroxy groups of lignin. Simultaneously a second reaction leading to the formation of ionic bonds between the same groups occurred. These new reactions have been clearly shown to involve several phenolic and alcohol hydroxyl… More >

M. Thébault^1,2, A. Pizzi1^3*, F.J. Santiago-Medina¹, F.M. Al-Marzouki³, S. Abdalla³

Journal of Renewable Materials, Vol.5, No.1, pp. 21-29, 2017, DOI:10.7569/JRM.2016.634116

Abstract Isocyanate-free polyurethane resins biosourced to a very high percentage level were prepared by the reaction of aminated mimosa tannin extract with commercial mimosa tannin extract prereacted with dimethyl carbonate. The reaction took place with ease at ambient temperature. Indications were that the polyurethanes obtained formed a hard film when cured at a temperature higher than 100 °C. Furthermore, the carbohydrate fraction of the tannin extract also appeared to be carbonated and reacted to generate isocyanate-free polyurethane linkages with the aminated tannins. This indicated that not only the polyphenolic fraction of the tannin extract, but also its other major component, can… More >

Jun Xie¹, Dapeng Sun¹, Jiaxiang Cai², Fuhong Cai^1,*

CMC-Computers, Materials & Continua, Vol.59, No.2, pp. 687-695, 2019, DOI:10.32604/cmc.2019.03658

Abstract The level of chemical oxygen demand (COD) is an important index to evaluate whether sewage meets the discharge requirements, so corresponding tests should be carried out before discharge. Fourier transform infrared spectroscopy (FTIR) and attenuated total reflectance (ATR) can detect COD in sewage effectively, which has advantages over conventional chemical analysis methods. And the selection of characteristic bands was one of the key links in the application of FTIR/ATR spectroscopy. In this work, based on the moving window partial least-squares (MWPLS) regression to select a characteristic wavelength, a method of equivalent wavelength selection was proposed combining with paired t-test equivalent… More >

Jun Xie¹, Chong Wang¹, Jiaxiang Cai², Fuhong Cai^1,*

CMC-Computers, Materials & Continua, Vol.57, No.2, pp. 261-268, 2018, DOI:10.32604/cmc.2018.03669

Abstract The rapid quantification method of human serum glucose was established by using the Fourier transform infrared spectroscopy (FTIR) and attenuated total reflection (ATR). By the subtracted spectra between glucose aqueous solution and de-ionized water, absorption peaks are calculated in fingerprint area. Based on these absorption peaks and multiple linear regression (MLR) model, discrete band selection method of absorption peaks disturbance model (APDM) was developed. 5 absorption peaks 1150 cm^-1, 1103 cm^-1, 1078 cm^-1, 1034 cm^-1, 991 cm^-1 were found in fingerprint area. Used these absorption peaks to establish absorption peaks disturbance model, the optimal wavelength combinations are 1140 cm^-1, 1096… More >