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Production and characterization of polymeric nanocomposite foams based on starch and cellulose nanofibers from oil palm mesocarp fiber

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Applied Nanoscience (Switzerland) 2025年第2期15卷 1-11页

作者： Souza, Mariana Costa Gonçalves, Ana Paula Bispo da Silva Oliveira, Emanoel Igor dos Santos, Juscivaldo Passos Lazzari, Lídia Kunz Zattera, Ademir José José, Nadia Mamede Chemical Engineering Graduate Program Polytechnic School Federal University of Bahia Bahia Salvador Brazil Department of Education Federal Institute of Education Science and Technology Feira de Santana Bahia Brazil Postgraduate Program in Process Engineering and Technologies University of Caxias Do Sul Rio Grande Do Sul Caxias Do Sul Brazil

The demand for sustainable and eco-friendly materials has promoted studies over the years to explore different polymeric materials that meet requirements such as biodegradability and sustainability. In this context, biopolymer materials based on cellulose nanoparticles and starch from different botanical sources have been investigated, aiming to achieve satisfactory performance. The present study aims to develop and characterize cassava starch foams based on density, scanning electron microscopy (SEM), and three-point flexure tests, and to evaluate the effect of cellulose nanofibers obtained from palm mesocarp fibers using the ultrafine friction grinding method after different processing times, characterized by X-ray diffractometry (XRD), microscopy, and chemical composition, as a reinforcing filler. The chemical composition and scanning electron microscopy revealed the effectiveness of the cellulose isolation process, with the analysis of the chemical composition revealing a cellulose content of 55.70% in the fibers after pulping and bleaching, in addition to changes in the visual characteristics of the material after the process aimed at isolating the cellulose. After grinding, XRD showed an increase in crystallinity (76.1% at the maximum grinding time), along with typical microscopy images of cellulose nanofibers. The analysis of the obtained nanocomposites provided insights into the role of these nanostructures in the thermo-expanded starch matrix, indicating that the nanofibers promoted changes such as an increase in mechanical properties and crystallinity, which contributed to improving overall mechanical performance. A 67.48% increase in flexural strength was achieved for the formulation with cellulose nanofibers that underwent 150 min of grinding, without causing major variations in density. © King Abdulaziz City for Science and Technology 2025.

关键词： Starch

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Drying behavior and thermodynamic properties of cashew nut almonds in thin layers: A mathematical modeling approach

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Heliyon 2025年第1期11卷 e41417页

作者： Almeida, Rafaela Duarte Martins Duarte, Maria Elita Mata, Mario Eduardo R. M. Cavalcanti Martins Duarte da Costa, Maria Eduarda Pessoa Melo, Mylena Olga Almeida, Renata Duarte Leite Filho, Manoel Tolentino Sousa, Severina de Silva Lucio, Alexandre da de Melo, Eloi Duarte Leite Cavalcante Neto, Jonas Alves Martins, Jorge Jaco Programa de Pós-Graduação em Engenharia e Gestão dos Recursos Naturais Universidade Federal Campina Grande Av. Aprigio Veloso 882 Paraíba Campina Grande 58429-900 Brazil Postgraduate Program in Process Engineering /CCT/ Federal University of Campina Grande/Campus I Av. Aprígio Veloso 882 Paraíba Campina Grande 58429-900 Brazil Unidade Acadêmica Engenharia Alimentos Universidade Federal Campina Grande Av. Aprigio Veloso 882 Paraíba Campina Grande 58429-900 Brazil Unidade Acadêmica Engenharia Química Universidade Federal Campina Grande Av. Aprigio Veloso 882 Paraíba Campina Grande 58429-900 Brazil Instituto Nacional do Semi-árido Av. Francisco Lopes de Almeida 4000 Serrotão Paraíba Campina Grande 58434-700 Brazil

Innovation in the drying process during the roasting of cashew nut almonds has the potential to significantly improve product quality. This study aimed to investigate the drying kinetics of the almond, comparing the experimental data with the mathematical models of Fick, Page, Cavalcanti Mata, and Henderson and Pabis. The research was conducted at the Laboratory of Physical Measurements and Drying of the Academic Unit of Food engineering at the Federal University of Campina Grande. For drying, equipment with high air velocity and precise temperature control was used, operating at 120, 140, 160, and 180 °C, with an air velocity of 3 m s⁻¹. Based on the drying kinetics parameters, the activation energy for each mathematical model was determined, which indicates the energy required to break the bonds that maintain water in the product. The thermodynamic properties of the process were also determined, which are essential to help understand the drying behavior of the fruit, optimize energy efficiency and the quality of the final product. The Fick model, using six terms in the series and considering the cylindrical shape of the almond, along with the other models analyzed, showed a good fit for the experimental data, as evidenced by the R² values obtained. For the Fick model, the R² values varied between 0.9675 and 0.9738, for the Page model, between 0.9809 and 0.9954, for the Cavalcanti Mata model, between 0.9921 and 0.9973 and for the Henderson and Pabis model, between 0.9906 and 0.9976, for the temperatures studied. © 2024

关键词： Diffusion coefficient Drying kinetics Heat transfer Moisture content

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Development of Bacterial Cellulose Membranes Incorporated with Plant Extracts

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Macromolecular Symposia 2022年第1期406卷 2200031-2200031页

作者： Neves, Eduarda Zeni Kumineck Junior, Sandro Rogério Katrucha, Graziéli Paulino Silveira, Victória Fonseca Silveira, Márcia Luciane Lange Pezzin, Ana Paula Testa Schneider, Andréa Lima dos Santos Garcia, Michele Cristina Formolo Apati, Giannini Pasiznick Department of Chemical Engineering University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil Postgraduate Program in Process Engineering University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil Postgraduate Program in Environment and Health University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil

A new generation of functional healing membranes has been researched to avoid infection and improve wound healing, combining wound moisture maintenance properties, exudate removal, antimicrobial activity, and the absence of side effects. Thus, this work aims to synthesize wound dressing membranes of bacterial cellulose (BC) incorporated with different plant extracts with antimicrobial properties. The BC membranes are synthesized by the bacterium Komagataeibacter hansenii and are associated with the extracts through the ex situ incorporation technique. The barbatimão extract presents the most significant total phenolic content and antimicrobial activity of the extracts researched. The determination of tannins and flavonoids confirms the extracts’ incorporation into the samples’ structure. The thermogravimetric analysis of the membranes incorporated with the extracts shows a reduction in the thermal stability relative to BC. The results show a good final extract for developing healing membranes with antimicrobial properties. © 2022 Wiley-VCH GmbH.

关键词： Membranes

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Transient heat transfer in a packed-bed elliptic cylindrical reactor: A finite-volume approach

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Defect and Diffusion Forum 2017年第1期380卷 79-85页

作者： Moura da Silva, R. Barbosa de Lima, A.G. Gomes de Oliveira, L. Vasconcellos Araújo, M. Sousa Santos, R. Federal University of Campina Grande Center of Science and Technology Process Engineering Postgraduate Program Campina Grande Paraíba58429-900 Brazil Federal Institute of Education Science and Technology of Paraíba Princesa Isabel Paraíba58755-000 Brazil Federal University of Campina Grande Center of Science and Technology Mechanical Engineering Department Campina Grande Paraíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Chemical Engineering Department Campina Grande Paraíba58429-900 Brazil

This work aims to develop a transient three-dimensional mathematical model using the elliptic cylindrical coordinate system, to predict heat transfer in a elliptic cylindrical packed fixed bed reactor. The model considers variable thermo physical properties and a parabolic temperature profile at the fluid inlet. The governing equation is solved using the finite volume method. Results of temperature profile along the reactor are presented and discussed at different *** was verified that the maximum heat transfer rate inside the reactor occurs near the extreme region close to minor semi-axis of the ellipse;the higher temperatures at the reactor surface are also in this region, along the entire height of the bed;the steady-state regime is reached at t = 4.5 s of process, presenting after this time interval,small axial temperature gradients and high radial gradients along of the reactor bed;the parabolic temperature profile give to the bed a predominance of radial temperature gradients, and the radial porosity profile favours a higher heat transfer rate at reactor surface. © 2017 Trans Tech Publications, Switzerland

关键词： Heat transfer

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Bacterial Cellulose Films for Biodegradable Packaging with Essential Oils

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Macromolecular Symposia 2024年第6期413卷

作者： Teixeira, Stefani Regina Zibetti Garcia, Michele Cristina Formolo Silva, Denise Abati Kasper Kurek, Ana Paula Schneider, AndréaLima dosSantos Pezzin, Ana Paula Testa Postgraduate Program in Process Engineering University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil Department of Chemical Engineering University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil

Petrochemical polymers provide most packaging materials in the food industry and cause environmental problems due to their non-biodegradability. Developing biodegradable polymers with additives is a strategy, and bacterial cellulose (BC) presents favorable properties for this application. This work aims to evaluate the effect of essential oils (EOs) of clove, cinnamon, basil, and oregano as additives in BC matrix for application in food packaging. BC membranes are synthesized by the bacteria Komagataeibacter hansenii and incorporated into EOs using ethanol as a solvent. The membranes are characterized by fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), antibacterial activity, and soil biodegradation. Furthermore, the samples are also tested for their antifungal potential on the surface of bread slices. FTIR analyses confirm the incorporation of EOs into BC membranes. TGA analysis indicates a slight increase in thermal stability for the incorporated samples. All samples show antibacterial potential, except BC, incorporated with the essential basil oil. The fungal analysis is performed by visually evaluating the appearance of filamentous fungi on the surface of the bread pieces. Soil biodegradation tests demonstrate mass loss for all membranes. © 2024 Wiley-VCH GmbH.

关键词： Cellulose

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Bacterial Cellulose Membranes Incorporated with Lipase for Oil Degradation

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Macromolecular Symposia 2024年第6期413卷

作者： Silveira, Victória Fonseca da Silva, Victória Mendes Junior, Sandro Rogério Kumineck Garcia, Michele Cristina Formolo Pezzin, Ana Paula Testa de Oliveira, Therezinha Maria Novais Schneider, Andrea Lima dos Santos Postgraduate Program in Health and Environment University of Joinville Region – UNIVILLE Santa Catarina Joinville89219-710 Brazil Department of Chemical Engineering University of Joinville Region – UNIVILLE Santa Catarina Joinville89219-710 Brazil Postgraduate Program in Process Engineering University of Joinville Region – UNIVILLE Santa Catarina Joinville89219-710 Brazil

The immobilization of enzymes increases their stability and allows their reuse, and bacterial cellulose (BC) is a material that can be used in this technique. This work aims to produce an enzymatic product to degrade oils and fats using BC as a matrix. Komagataeibacter hansenii bacteria produce BC membranes, and lipase is immobilized on the membranes by ex situ method. Then, the surface of the membranes is modified with zein, a hydrophobic corn protein. The membranes are characterized by TGA, FTIR, scanning electron microscopy (SEM) analysis and oil degradation test. TGA demonstrates higher stability for the membranes with lipase and zein. The FTIR spectrum of pure BC membrane and zein-modified membrane are very similar because of the high zein coating. SEM analysis shows that zein-modified membranes with lipase present smaller amounts of pores. Finally, using soy oil, lipase degrades oil even after immobilization during the degradation test. © 2024 Wiley-VCH GmbH.

关键词： Nafion membranes

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Biosorption of chromium by live and dead cells of Bacillus nitratireducens isolated from textile effluent

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Chemosphere 2024年 359卷 142389页

作者： Imron, Muhammad Fauzul Setiawan, Wahyu Putranto, Trisnadi Widyaleksono Catur Abdullah, Siti Rozaimah Sheikh Kurniawan, Setyo Budi Study Program of Environmental Engineering Department of Biology Faculty of Science and Technology Universitas Airlangga Campus C UNAIR Jalan Mulyorejo Surabaya60115 Indonesia Department of Water Management Faculty of Civil Engineering and Geosciences Delft University of Technology Stevinweg 1 CN Delft2628 Netherlands Study Program of Environmental Science Postgraduate Program Sriwijaya University Palembang30139 Indonesia Department of Chemical and Process Engineering Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia UKM Bangi Selangor 43600 Malaysia

Bacillus nitratireducens was isolated from textile effluent and showed high tolerance to chromium (Cr), reaching up to a 1000 mg/L MIC value. This research was aimed at utilizing biosorbents from live and dead cells of B. nitratireducens to remove Cr from an aqueous solution. A batch biosorption test was performed, and mechanisms analysis was approached by an adsorption-desorption test, SEM-EDS, and FTIR analysis. Cr removal by dead cells in 25, 50, and 100 mg/L of Cr were 58.99 ± 0.7%, 69.8 ± 0.2%, and 82.87 ± 0.11%, respectively, while that by live cells was 73.08 ± 1.9%, 80.27 ± 6.33%, and 86.17 ± 1.93%, respectively. Live cells showed significantly higher Cr removal and adsorption capacities as compared to dead cells. In all concentrations, absorption contributed more than adsorption to the Cr removal by both live and dead cells. Absorption of Cr was subjected to occur due to passive mechanisms in dead cells while involving some active mechanisms in live cells. SEM-EDS confirmed the detection of Cr on the cell surface, while FTIR revealed the shifting of some peaks after the biosorption test, suggesting interactions between Cr and functional groups. Further TEM analysis is suggested to be conducted as a future approach to reveal the inner structure of cells and confirm the involvement of absorption mechanisms. © 2024 Elsevier Ltd

关键词： Heavy metals

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Effect of Lyophilized Peach Incorporation on Yam Cookies Quality: Oxidative Stability, Nutritional Potential and Antioxidant Properties

SSRN

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SSRN 2024年

作者： Carpes, Solange Teresinha Souza da Silva, Letícia Perin, Ellen Cristina Fontoura, Bruno Henrique Pereira, Edimir Andrade de Camargo, Robson Rosa Bianchin, Mirelli de Oliveira, Jonas Cardoso Citadin, Idemir Department of Chemistry Postgraduate Program in Chemical and Biochemical Process Technology Federal Technological University of Paraná campus Pato Branco PO Box 571 PR Pato BrancoCEP 85503-390 Brazil Department of Agronomy Postgraduate Program in Agronomy Federal Technological University of Paraná campus Pato Branco PO Box 571 PR Pato BrancoCEP 85503-390 Brazil Department of Chemistry Postgraduate Program in Chemical State University of Maringá Av. Colombo 5790 - Zona 7 PR Maringá87020-900 Brazil Department of Food Engineering Federal Technological University of Paraná campus Francisco Beltrão Linha Santa Bárbara s/n PR Francisco Beltrão85601-970 Brazil

This study aimed to increase oxidative stability and enhance yam flour cookies' nutritional and antioxidant properties by incorporating lyophilized peach (LP). The cookies were subjected to two storage conditions: one with exposure to light and one in darkness for 60 days at room temperature. Four formulations were tested: a control (F1), F2 and F3 with 10% and 20% LP, respectively, and F4 with a synthetic antioxidant (SA). The cookies were a good source of protein and fiber. The incorporation of LP into yam cookies exhibited a strong antioxidative effect. Besides, the F3 shows oxidative stability comparable to the SA (F4), measured by TBARS values, under both storage conditions. However, light exposure influenced the retention of phenolics with antioxidant activity, with higher levels observed in cookies stored in darkness. The LP effectively inhibited oxidative processes, demonstrating its potential as an alternative to SA for improving the oxidative stability of yam cookies. © 2024, The Authors. All rights reserved.

关键词： Fruits

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FFG-61 PROTOTYPE DIGITAL TECHNICAL LIBRARY

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NAVAL ENGINEERS JOURNAL 1992年第2期104卷 58-68页

作者： VINROOT, CA ORNER, JG USN Capt. Charles A. Vinroot USN (Ret.)retired from the U.S. Navy in September 1991 following over 27 years of active duty as an engineering duty officer. He holds a BSEE from North Carolina State University and a MSEE and professional degree from the U.S. Naval Postgraduate School. During his naval career he served on USSIndependence (CVA-62) and USSLuce (DLC-7/DDC-38). He also served at Supship Quincy Mass. and Hunters Point Naval Shipyard. He was stationed in Washington D.C. with assignments at CNO (OP 98) ASN (S&L) and the Naval Sea Systems Command. Captain Vinroot was technical director of the Battleship Reactivation Program (PMS 378) technical director of the Destroyer Acquisition Program (PMS 389) and deputy program manager of the Amphibious Warfare and Strategic Sealift Program (PMS 377). Most recently he served as program manager for Gas Turbine Surface Combatants (PMS 314) and Surface Combatants (PMS 330). Captain Vinroot is now employed by PRC Inc. and serves as technical director for the Advanced Technology Division in Crystal City Va. Jeffery G. Ornergraduated from Wittenberg University in Springfield Ohio in 1979 with a bachelor of arts degree in political science and earned a master's of science degree in business from The American University in Washington D.C. in 1982. He has ten years of professional experience with the Naval Sea Systems Command in positions with responsibilities for logistic support planning policy and delivery computer-aided acquisition and logistic support and Fleet Modernization Program (FMP) and ship construction issues. He was a key player in establishing the current FMP integrated logistic support (ILS) process and in implementing of the Ships' Configuration and Logistic Support Information System (SCLSIS). His current position as Fleet Logistic Support Branch head for the Surface Combatant Program includes responsibility for logistic support and management of ship configuration and logistic data for all surface combatant ships (except for Aegis ships). In

USS Ingraham (FFG-61) is the prototype ship for NavSea's Advanced Technical Information System (ATIS). ATIS is a digital technical library, which holds on optical disks the ship's 2,000 technical manuals and 73,000 drawing sheets. It contains a detailed ship's configuration index (derived from SCLSIS) to lead the user to the proper drawing or manual, and it replaces the ship's aperture cards and the second (library) copy of the technical manuals. ATIS, and the data standards established and tested through ATIS development, will be the technical library portion of micro-SNAP and SNAP III. It also forms an important part of NavSea's plans to utilize EDMICS data. This paper describes the goals and technical concepts behind the development of ATIS. Problems encountered, solutions developed, and lessons learned are detailed. Special attention was paid to the application of the Computer Aided Acquisition and Logistic Support (CALS) standards, problems caused by conflicts and ambiguities in those standards, the standards. Original program goals are compared with actual operational experiences. Plans for future expansion are outlined, including applications of this technology in the availability planning and execution process. A comparison is developed among the various methods of optical imaging and their costs and benefits.

关键词： Information Retrieval Systems

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Drying Behavior and Thermodynamic Properties of Cashew Nut Almonds in Thin Layers: A Mathematical Modeling Approach

SSRN

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SSRN 2024年

作者： Almeida, Rafaela Duarte Martins Duarte, Maria Elita Duarte da Costa, Maria Eduarda Martins Melo, Mylena Olga Pessoa Almeida, Renata Duarte Filho, Manoel Tolentino Leite Alves Martins, Jorge Jacó de Sousa, Severina Lúcio, Alexandre da Silva de Melo, Elói Duarte Leite Cavalcante Neto, Jonas Duarte Cavalcanti Mata, Mário Eduardo R.M. Programa de Pós-Graduação em Engenharia e Gestão dos Recursos Naturais Universidade Federal Campina Grande Av. Aprigio Veloso 882 Paraíba Campina Grande58429-900 Brazil Postgraduate Program in Process Engineering CCT Federal University of Campina Grande Campus I Av. Aprígio Veloso 882 Paraíba Campina Grande58429-900 Brazil Unidade Acadêmica Engenharia Alimentos Universidade Federal Campina Grande Av. Aprigio Veloso 882 Paraíba Campina Grande58429-900 Brazil Unidade Acadêmica Engenharia Química Universidade Federal Campina Grande Av. Aprigio Veloso 882 Paraíba Campina Grande58429-900 Brazil Instituto Nacional do Semi-árido Av. Francisco Lopes de Almeida 4000 Serrotão Paraíba Campina Grande58434-700 Brazil

关键词： Drying

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