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1.
Environ Res ; 214(Pt 4): 114149, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36007570

RESUMO

Biodiesel is renewable, biodegradable, biocompatible (non-toxic) and environmentally friendly, which emits less pollution than traditional fossil-based diesel, making it the most promising and ideal option. However, biodiesel is facing many current issues, mostly related to the utilisation of homogeneous catalytic technology, and this circumstance obstructs its potential development and advancement. Therefore, new pathways for biodiesel production need to be explored, and the aforementioned issues need to be addressed. Recently, a study was conducted on the impregnated magnetic biochar derived from a waste palm kernel shell (PKS) catalyst that can replace conventional catalysts due to its reusability property. Nevertheless, the environmental impacts of impregnated magnetic biochar derived from waste PKS catalyst for biodiesel production are yet to be studied. This study focuses on the evaluation of the life cycle assessment (LCA) of palm-based cooking oil for biodiesel production catalysed by impregnated magnetic biochar derived from waste PKS. Simapro was used in this study to evaluate the impact assessment methodologies. Case 1 (6.64 × 102 Pt) has contributed less to environmental impacts than Case 2 (1.83 × 103 Pt). This indicates purchasing refined palm oil for biodiesel production may reduce environmental impacts by 64% compared to producing biodiesel from raw fruit bunches. In the midpoint assessment, the transesterification process was identified as the hotspot and marine aquatic ecotoxicity as the highest impact category with a value of 1.00 × 106 kg 1,4-DB eq for 1 tonne of biodiesel produced. The endpoint results showed that Case 1 revealed the greatest impact on the transesterification process, with cumulative damage of 461 Pt. Scenario without processing the raw palm fruit bunches to obtained palm oil was better than Case 2. Further research should be conducted on life cycle cost and sensitivity analysis to evaluate the economic feasibility and promote sustainable biodiesel production.


Assuntos
Biocombustíveis , Óleos de Plantas , Animais , Catálise , Carvão Vegetal , Estágios do Ciclo de Vida , Fenômenos Magnéticos , Óleo de Palmeira
2.
Sci Rep ; 12(1): 6742, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35468936

RESUMO

The less phytopathogen susceptibility in Himalayan Brassica rapa L. has made it an exceptional crop eluding synthetic pesticide inputs, thereby guarantying economically well-founded and ecologically sustainable agriculture. The relevance of niche microflora of this crop has not been deliberated in this context, as endosymbiosiome is more stable than their rhizosphere counterparts on account of their restricted acquaintance with altering environment; therefore, the present investigation was carried out to study the endophytic microfloral dynamics across the B. rapa germplasm in context to their ability to produce chitinase and to characterize the screened microflora for functional and biochemical comportments in relevance to plant growth stimulation. A total of 200 colonies of bacterial endophytes were isolated from the roots of B. rapa across the J&K UT, comprising 66 locations. After morphological, ARDRA, and sequence analysis, eighty-one isolates were selected for the study, among the isolated microflora Pseudomonas sp. Bacillus sp. dominated. Likewise, class γ-proteobacteria dominated, followed by Firmicutes. The diversity studies have exposed changing fallouts on all the critical diversity indices, and while screening the isolated microflora for chitinase production, twenty-two strains pertaining to different genera produced chitinase. After carbon source supplementation to the chitinase production media, the average chitinase activity was significantly highest in glycerol supplementation. These 22 strains were further studied, and upon screening them for their fungistatic behavior against six fungal species, wide diversity was observed in this context. The antibiotic sensitivity pattern of the isolated strains against chloramphenicol, rifampicin, amikacin, erythromycin, and polymyxin-B showed that the strains were primarily sensitive to chloramphenicol and erythromycin. Among all the strains, only eleven produced indole acetic acid, ten were able to solubilize tricalcium phosphate and eight produced siderophores. The hydrocyanic acid and ammonia production was observed in seven strains each. Thus, the present investigation revealed that these strains could be used as potential plant growth promoters in sustainable agriculture systems besides putative biocontrol agents.


Assuntos
Brassica rapa , Quitinases , Bactérias , Cloranfenicol , Eritromicina , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S
3.
Sci Rep ; 11(1): 843, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33437011

RESUMO

Modified multi-walled carbon nanotubes (f-MWCNTs) and hydroxyapatite nanorods (n-HA) were reinforced into polypropylene (PP) with the support of a melt compounding approach. Varying composition of f-MWCNTs (0.1-0.3 wt.%) and nHA (15-20 wt.%) were reinforced into PP, to obtain biocomposites of different compositions. The morphology, thermal and mechanical characteristics of PP/n-HA/f-MWCNTs were observed. Tensile studies reflected that the addition of f-MWCNTs is advantageous in improving the tensile strength of PP/n-HA nanocomposites but decreases its Young's modulus significantly. Based on the thermal study, the f-MWCNTs and n-HA were known to be adequate to enhance PP's thermal and dimensional stability. Furthermore, MTT studies proved that PP/n-HA/f-MWCNTs are biocompatible. Consequently, f-MWCNTs and n-HA reinforced into PP may be a promising nanocomposite in orthopedics industry applications such as the human subchondral bone i.e. patella and cartilage and fabricating certain light-loaded implants.

4.
Sci Rep ; 10(1): 21960, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319818

RESUMO

The main goal of the present work was to develop a value-added product of biodegradable material for sustainable packaging. The use of agriculture waste-derived carboxymethyl cellulose (CMC) mainly is to reduce the cost involved in the development of the film, at present commercially available CMS is costly. The main focus of the research is to translate the agricultural waste-derived CMC to useful biodegradable polymer suitable for packaging material. During this process CMC was extracted from the agricultural waste mainly sugar cane bagasse and the blends were prepared using CMC (waste derived), gelatin, agar and varied concentrations of glycerol; 1.5% (sample A), 2% (sample B), and 2.5% (sample C) was added. Thus, the film derived from the sample C (gelatin + CMC + agar) with 2.0% glycerol as a plasticizer exhibited excellent properties than other samples A and B. The physiochemical properties of each developed biodegradable plastics (sample A, B, C) were characterized using Fourier Transform Infra-Red (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA). The swelling test, solubility in different solvents, oil permeability coefficient, water permeability (WP), mechanical strength of the produced material was claimed to be a good material for packaging and meanwhile its biodegradability (soil burial method) indicated their environmental compatibility nature and commercial properties. The reflected work is a novel approach, and which is vital in the conversion of organic waste to value-added product development. There is also another way to utilize commercial CMC in preparation of polymeric blends for the packaging material, which can save considerable time involved in the recovery of CMC from sugarcane bagasse.

5.
Sci Rep ; 10(1): 20106, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33208815

RESUMO

Strain sensors in the form of buckypaper (BP) infiltrated with various polymers are considered a viable option for strain sensor applications such as structural health monitoring and human motion detection. Graphene has outstanding properties in terms of strength, heat and current conduction, optics, and many more. However, graphene in the form of BP has not been considered earlier for strain sensing applications. In this work, graphene-based BP infiltrated with polyvinyl alcohol (PVA) was synthesized by vacuum filtration technique and polymer intercalation. First, Graphene oxide (GO) was prepared via treatment with sulphuric acid and nitric acid. Whereas, to obtain high-quality BP, GO was sonicated in ethanol for 20 min with sonication intensity of 60%. FTIR studies confirmed the oxygenated groups on the surface of GO while the dispersion characteristics were validated using zeta potential analysis. The nanocomposite was synthesized by varying BP and PVA concentrations. Mechanical and electrical properties were measured using a computerized tensile testing machine, two probe method, and hall effect, respectively. The electrical conducting properties of the nanocomposites decreased with increasing PVA content; likewise, electron mobility also decreased while electrical resistance increased. The optimization study reports the highest mechanical properties such as tensile strength, Young's Modulus, and elongation at break of 200.55 MPa, 6.59 GPa, and 6.79%, respectively. Finally, electrochemical testing in a strain range of ε ~ 4% also testifies superior strain sensing properties of 60 wt% graphene BP/PVA with a demonstration of repeatability, accuracy, and preciseness for five loading and unloading cycles with a gauge factor of 1.33. Thus, results prove the usefulness of the nanocomposite for commercial and industrial applications.

6.
Waste Manag ; 118: 626-636, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33011540

RESUMO

Due to its environment-friendly and replenishable characteristics, biodiesel has the potential to substitute fossil fuels as an alternative source of energy. Although biodiesel has many benefits to offer, manufacturing biodiesel on an industrial scale is uneconomical as a high cost of feedstock is required. A novel sulfonated and magnetic catalyst synthesised from a palm kernel shell (PMB-SO3H) was first introduced in this study for methyl ester or biodiesel production to reduce capital costs. The wasted palm kernel shell (PKS) biochar impregnated with ferrite Fe3O4 was synthesised with concentrated sulphuric acid through the sulfonation process. The SEM, EDX, FTIR, VSM and TGA characterization of the catalysts were presented. Then, the optimisation of biodiesel synthesis was catalysed by PMB-SO3H via the Response Surface Methodology (RSM). It was found that the maximum biodiesel yield of 90.2% was achieved under these optimum operating conditions: 65 °C, 102 min, methanol to oil ratio of 13:1 and the catalyst loading of 3.66 wt%. Overall, PMB-SO3H demonstrated acceptable catalysing capability on its first cycle, which subsequently showed a reduction of the reusability performance after 4 cycles. An important practical implication is that PMB-SO3H can be established as a promising heterogeneous catalyst by incorporating an iron layer which can substantially improve the catalyst separation performance in biodiesel production.


Assuntos
Biocombustíveis , Óleos de Plantas , Carvão Vegetal , Esterificação , Fenômenos Magnéticos
7.
Sci Rep ; 10(1): 15326, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948806

RESUMO

This study deals with an experimental investigation to assess the characteristics of a modified common rail direct injection (CRDI) engine utilizing diesel, Mahua biodiesel, and their blends with synthesized zinc oxide (ZnO) nano additives. The physicochemical properties of diesel, diesel + 30 ppm ZnO nanoparticles (D10030), 20% Mahua biodiesel (MOME20), and Mahua biodiesel (20%) + 30 ppm ZnO nanoparticles (MOME2030) were measured in accordance to the American Society for Testing and Materials standards. The effects of modification of fuel injectors (FI) holes (7-hole FI) and toroidal reentrant combustion chamber (TRCC) piston bowl design on the performance of CRDI using different fuel blends were assessed. For injection timings (IT) and injection opening pressure (IOP) average increase in brake thermal efficiency for fuel blend D10030 and MOME2030 was 9.65% and 16.4%, and 8.83% and 5.06%, respectively. Also, for IT and IOP, the average reductions in brake specific fuel consumption, smoke, carbon monoxide, hydrocarbon and nitrogen oxide emissions for D10030 and MOME2030 were 10.9% and 7.7%, 18.2% and 8.6%, 12.6% and 11.5%, 8.74% and 13.1%, and 5.75% and 7.79%, respectively and 15.5% and 5.06%, 20.33% and 6.20%, 11.12% and 24.8%, 18.32% and 6.29%, and 1.79% and 6.89%, respectively for 7-hole fuel injector and TRCC. The cylinder pressure and heat release rate for D10030 and MOME2030 were enhanced by 6.8% and 17.1%, and 7.35% and 12.28%. The 7-hole fuel injector with the nano fuel blends at an injection timing and pressure of 10° btdc and 900 bar demonstrated the overall improvement of the engine characteristics due to the better air quality for fuel mixing. Similarly, the TRCC cylinder bowl geometry illustrated advanced ignition due to an improved swirl and turbulence. Also, the engine test results demonstrated that 30 ppm of ZnO nanoparticles in Mahua biodiesel (MOME2030) and diesel (D10030) with diethyl ether resulted overall enhancement of CRDI engine characteristics.

8.
Environ Res ; 183: 109158, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32044575

RESUMO

Jicama peroxidase (JP) immobilized functionalized Buckypaper/Polyvinyl alcohol (BP/PVA) membrane was synthesized and evaluated as a promising nanobiocomposite membrane for methylene blue (MB) dye removal from aqueous solution. The effects of independent process variables, including pH, agitation speed, initial concentration of hydrogen peroxide (H2O2), and contact time on dye removal efficiency were investigated systematically. Both Response Surface Methodology (RSM) and Artificial Neural Network coupled with Particle Swarm Optimization (ANN-PSO) approaches were used for predicting the optimum process parameters to achieve maximum MB dye removal efficiency. The best optimal topology for PSO embedded ANN architecture was found to be 4-6-1. This optimized network provided higher R2 values for randomized training, testing and validation data sets, which are 0.944, 0.931 and 0.946 respectively, thus confirming the efficacy of the ANN-PSO model. Compared to RSM, results confirmed that the hybrid ANN-PSO shows superior modeling capability for prediction of MB dye removal. The maximum MB dye removal efficiency of 99.5% was achieved at pH-5.77, 179 rpm, ratio of H2O2/MB dye of 73.2:1, within 229 min. Thus, this work demonstrated that JP-immobilized BP/PVA membrane is a promising and feasible alternative for treating industrial effluent.


Assuntos
Azul de Metileno , Redes Neurais de Computação , Pachyrhizus , Poluentes Químicos da Água , Adsorção , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Cinética , Peroxidase , Peroxidases , Álcool de Polivinil
9.
Environ Pollut ; 259: 113940, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31931415

RESUMO

Jicama peroxidase (JP) was covalently immobilized onto functionalized multi-walled carbon nanotube (MWCNT) Buckypaper/Polyvinyl alcohol (BP/PVA) membrane and employed for degradation of methylene blue dye. The parameters of the isotherm and kinetic models are estimating using ant colony optimization (ACO), which do not meddle the non-linearity form of the respective models. The proposed inverse modelling through ACO optimization was implemented, and the parameters were evaluated to minimize the non-linear error functions. The adsorption of MB dye onto JP-immobilized BP/PVA membrane follows Freundlich isotherm model (R2 = 0.99) and the pseudo 1st order or 2nd kinetic model (R2 = 0.980 & 0.968 respectively). The model predictions from the parameters estimated by ACO resulted values close the experimental values, thus inferring that this approach captured the inherent characteristics of MB adsorption. Moreover, the thermodynamic studies indicated that the adsorption was favourable, spontaneous, and exothermic in nature. The comprehensive structural analyses have confirmed the successful binding of peroxidase onto BP/PVA membrane, as well as the effective MB dye removal using immobilized JP membrane. Compared to BP/PVA membrane, the reusability test revealed that JP-immobilized BP/PVA membrane has better dye removal performances as it can retain 64% of its dye removal efficiency even after eight consecutive cycles. Therefore, the experimental results along with modelling results demonstrated that JP-immobilized BP/PVA membrane is expected to bring notable impacts for the development of effective green and sustainable wastewater treatment technologies.


Assuntos
Algoritmos , Azul de Metileno , Modelos Químicos , Álcool de Polivinil , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Peroxidase , Peroxidases , Termodinâmica
10.
Sci Rep ; 9(1): 5445, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30931991

RESUMO

Polymer composites are fabricated by incorporating fillers into a polymer matrix. The intent for addition of fillers is to improve the physical, mechanical, chemical and rheological properties of the composite. This study reports on a unique polymer composite using hydrochar, synthesised by microwave-assisted hydrothermal carbonization of rice husk, as filler in polylactide matrix. The polylactide/hydrochar composites were fabricated by incorporating hydrochar in polylactide at 5%, 10%, 15% and 20 wt% by melt processing in a Haake rheomix at 170 °C. Both the neat polylactide and polylactide/hydrochar composite were characterized for mechanical, structural, thermal and rheological properties. The tensile modulus of polylactide/hydrochar composites was improved from 2.63 GPa (neat polylactide) to 3.16 GPa, 3.33 GPa, 3.54 GPa, and 4.24 GPa after blending with hydrochar at 5%, 10%, 15%, and 20%, respectively. Further, the incorporation of hydrochar had little effect on storage modulus (G') and loss modulus (G″). The findings of this study reported that addition of hydrochar improves some characteristics of polylactide composites suggesting the potential of hydrochar as filler for polymer/hydrochar composites.


Assuntos
Oryza/química , Poliésteres/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Micro-Ondas , Reologia , Análise Espectral/métodos , Temperatura , Termogravimetria
11.
Sci Rep ; 9(1): 2215, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30778111

RESUMO

Surface modified Multi-walled carbon nanotubes (MWCNTs) Buckypaper/Polyvinyl Alcohol (BP/PVA) composite membrane was synthesized and utilized as support material for immobilization of Jicama peroxidase (JP). JP was successfully immobilized on the BP/PVA membrane via covalent bonding by using glutaraldehyde. The immobilization efficiency was optimized using response surface methodology (RSM) with the face-centered central composite design (FCCCD) model. The optimum enzyme immobilization efficiency was achieved at pH 6, with initial enzyme loading of 0.13 U/mL and immobilization time of 130 min. The results of BP/PVA membrane showed excellent performance in immobilization of JP with high enzyme loading of 217 mg/g and immobilization efficiency of 81.74%. The immobilized system exhibited significantly improved operational stability under various parameters, such as pH, temperature, thermal and storage stabilities when compared with free enzyme. The effective binding of peroxidase on the surface of the BP/PVA membrane was evaluated and confirmed by Field emission scanning electron microscopy (FESEM) coupled with Energy Dispersive X-Ray Spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). This work reports the characterization results and performances of the surface modified BP/PVA membrane for peroxidase immobilization. The superior properties of JP-immobilized BP/PVA membrane make it promising new-generation nanomaterials for industrial applications.


Assuntos
Enzimas Imobilizadas , Membranas Artificiais , Nanocompostos , Nanotubos de Carbono , Peroxidase/química , Álcool de Polivinil , Ativação Enzimática , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Nanocompostos/química , Nanocompostos/ultraestrutura , Nanotubos de Carbono/química , Álcool de Polivinil/química , Reprodutibilidade dos Testes , Análise Espectral , Temperatura , Termodinâmica
12.
Sci Rep ; 8(1): 17295, 2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30470825

RESUMO

Buckypaper (BP)/polymer composites are viewed as a viable option to improve the strain transfer across the buckypaper strain sensor by means of providing better interfacial bonding between the polymer and carbon nanotubes (CNTs). Multiwall carbon nanotubes (MWCNTs) BP/polyvinyl alcohol (PVA) composites were fabricated by a sequence of vacuum filtration and polymer intercalation technique. The optimized conditions for achieving a uniform and stable dispersion of MWCNTs were found to be using ethanol as a dispersion medium, 54 µm ultrasonic amplitude and 40 min sonication time. FTIR analysis and SEM spectra further confirmed the introduction of oxygenated groups (-COOH) on the surface of MWCNTs BP and the complete infiltration of PVA into the porous MWCNTs network. At MWCNTs content of 65 wt. %, the tensile strength, Young's modulus and elongation-at-break of PVA-infiltrated MWCNTs BP achieved a maximum value of 156.28 MPa, 4.02 GPa and 5.85%, improved by 189%, 443% and 166% respectively, as compared to the MWCNTs BP. Electrical characterization performed using both two-point probe method and Hall effect measurement showed that BP/PVA composites exhibited reduced electrical conductivity. From the electromechanical characterization, the BP/PVA composites showed improved sensitivity with a gauge factor of about 1.89-2.92. The cyclic uniaxial tensile test validated the high reproducibility and hysteresis-free operation of 65-BP/PVA composite under 3 loading-unloading cycles. Characterization results confirmed that the flexible BP/PVA composite (65 wt. %) with improved mechanical and electromechanical properties is suitable for strain sensing applications in structural health monitoring and wearable technology, as an alternative choice to the fragile nature of conventional metallic strain sensors.

13.
J Nanosci Nanotechnol ; 15(12): 9571-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26682380

RESUMO

Carbon nanotubes (CNFs) were produced by gas phase single stage microwave assisted chemical vapour deposition (MA-CVD) using ferrocene as a catalyst and acetylene (C2H2) and hydrogen (H2) as precursor gases. The effect of the process parameters such as microwave power, radiation time, and gas ratio of C2H2/H2 was investigated. The CNFs were characterized using scanning and transmission electron microscopy (TEM), and by thermogravimetric analysis (TGA). Results reveal that the optimized conditions for CNF production were 1000 W reaction power, 35 min radiation time, and 0.8 gas ratio of C2H2/H2. TEM analyses revealed that the uniformly dispersed CNFs diameters ranging from 115-131 nm. The TGA analysis showed that the purity of CNF produced was 93%.

14.
Bioresour Technol ; 178: 65-69, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25278112

RESUMO

In this study, pyrolysis technique was utilized for converting palm oil sludge to value added materials: bio-oil (liquid fuel) and bio-char (soil amendment). The bio-oil yield obtained was 27.4±1.7 wt.% having a heating value of 22.2±3.7 MJ/kg and a negligible ash content of 0.23±0.01 wt.%. The pH of bio-oil was in alkaline region. The bio-char yielded 49.9±0.3 wt.%, which was further investigated for sorption efficiency by adsorbing metal (Cd(2+) ions) from water. The removal efficiency of Cd(2+) was 89.4±2%, which was almost similar to the removal efficiency of a commercial activated carbon. The adsorption isotherm was well described by Langmuir model. Therefore, pyrolysis is proved as an efficient tool for palm oil sludge management, where the waste was converted into valuable products.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Carvão Vegetal/química , Óleos de Plantas/química , Esgotos/química , Adsorção , Biomassa , Cádmio/química , Carbono/química , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Íons , Metais/química , Óleo de Palmeira , Temperatura , Termogravimetria , Água/química
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