Oil spill remediation plays a vital role in mitigating the environmental impacts caused by oil spills. The chemical method is one of the widely recognized approaches in chemical surfactants. However, the most commonly used chemical surfactants are toxic and non-biodegradable. Herein, two biocompatible and biodegradable surfactants were synthesized from orange peel using the ionic liquid 1-butyl-3-methylimidazolium chloride (BMIMCl) and organic solvent dimethylacetamide (CH3CN(CH3)2) as reaction media. The acronyms SOPIL and SOPOS refer to the surfactants prepared with BMIMCl and dimethylacetamide, respectively. The surface tension, dispersant effectiveness, optical microscopy, and emulsion stability test were conducted to examine the comparative performance of the synthesized surfactants. The Baffled flask test (BFT) was carried out to determine the dispersion effectiveness. The toxicity test was performed against zebrafish (Danio rerio), whereas the closed bottle test (CBT) evaluated biodegradability. The results revealed that the critical micelle concentration (CMC) value of SOPIL was lower (8.57 mg/L) than that of SOPOS (9.42 mg/L). The dispersion effectiveness values for SOPIL and SOPOS were 69.78% and 40.30%, respectively. The acute toxicity test demonstrated that SOPIL was 'practically non-toxic' with a median lethal concentration of more than 1000 mg/L after 96 h. The biodegradation rate was recorded as higher than 60% for both surfactants within 28 days, demonstrating their readily biodegradable nature. Considering these attributes, biocompatible and biodegradable surfactants derived from orange peel emerge as a promising and sustainable alternative for oil spill remediation.
Glycerol pretreatment is a promising method for the environmentally-friendly transformation of lignocellulosic materials into sustainable cellulose-rich raw materials (i.e., biopolymer) to fabricate biocomposites. Here, a comparison of aqueous acidified glycerol (AAG) pretreatment of wheat straw (WS) with alkaline, hot water, and dilute acid pretreatments on the thermal and mechanical characteristics of their fabricated composite board is presented. A comparison of total energy expenditure during WS pretreatment with AAG and other solutions was estimated and a comparative influence of AAG processing on lignocellulosic constituents and thermal stability of WS fiber was studied. Results imply that AAG pretreatment was superior in generating cellulose-rich fiber (CRF) as compared to other pretreatments and enhanced the cellulose contents by 90% compared to raw WS fiber. Flexural strength of acidic (40.50 MPa) and hot water treated WS composite (38.71 MPa) was higher compared to the value of 33.57 MPa for untreated composite, but AAG-treated composites exhibited lower values of flexural strength (22.22 MPa) compared to untreated composite samples. Conversely, AAG pretreatment consumed about 56% lesser energy for each kg of WS processed as compared to other pretreatments. These findings recognize that glycerol pretreatment could be a clean and new pretreatment strategy to convert agricultural waste into high-quality CRF as a sustainable raw material source for engineered biocomposite panels.
The synthesis of new surfactants helps to mitigate the environmental and financial effects of oil spills by providing efficient cleanup options. Herein, this study provides the development of a binary mixture of Span 80 and Choline myristate [Cho][Mys], a surface-active ionic liquid (SAIL) as green dispersant for oil spill remediation. The synergistic interaction at a 60:40 (w/w) ratio significantly lowered the critical micelle concentration (cmc) to 0.029 mM. Dispersion efficiency tests with Arab crude oil showed optimal performance at a 60:40 ratio of Span 80 and [Cho][Mys] (1:25 dispersant to oil ratio, v/v), achieving 81.16 % dispersion effectiveness in the baffled flask test. The binary mixture demonstrated superior emulsion stability (6 h) and the lowest interfacial tension (1.12 mN/m). Acute toxicity experiments revealed the dispersant's practical non-toxicity with an LC50 value of 600 mg/L. Overall, this environmentally benign surfactant combination shows promise as a safe and effective oil spill dispersant.
Background Little is known regarding whether arterial stiffness and atherosclerotic burden are each independently associated with brain structural changes. Simultaneous assessments of both arterial stiffness and atherosclerotic burden in associations with brain could provide insights into the mechanisms of brain structural changes. Methods and Results Using data from the SESSA (Shiga Epidemiological Study of Subclinical Atherosclerosis), we analyzed data among 686 Japanese men (mean [SD] age, 67.9 [8.4] years; range, 46-83 years) free from history of stroke and myocardial infarction. Brachial-ankle pulse wave velocity and coronary artery calcification on computed tomography scans were measured between March 2010 and August 2014. Brain volumes (total brain volume, gray matter, Alzheimer disease signature and prefrontal) and brain vascular damage (white matter hyperintensities) were quantified using brain magnetic resonance imaging from January 2012 through February 2015. In multivariable adjustment models including mean arterial pressure, when brachial-ankle pulse wave velocity and coronary artery calcification were entered into the same models, the β (95% CI) for Alzheimer disease signature volume for each 1-SD increase in brachial-ankle pulse wave velocity was -0.33 (-0.64 to -0.02), and the unstandardized β (95% CI) for white matter hyperintensities for each 1-unit increase in coronary artery calcification was 0.68 (0.05-1.32). Brachial-ankle pulse wave velocity and coronary artery calcification were not statistically significantly associated with total brain and gray matter volumes. Conclusions Among Japanese men, higher arterial stiffness was associated with lower Alzheimer disease signature volumes, whereas higher atherosclerotic burden was associated with brain vascular damage. Arterial stiffness and atherosclerotic burden may be independently associated with brain structural changes via different pathways.
PHAs (polyhydroxyalkanoates) have emerged as biodegradable plastics more strongly in the 20th century. A wide range of bacterial species along with fungi, plants, oilseed crops and carbon sources have been used extensively to synthesize PHA on large scales. Alteration of PHA monomers in their structures and composition has led to the development of biodegradable and biocompatible polymers with highly specific mechanical properties. This leads to the incorporation of PHA in numerous biomedical applications within the previous decade. PHAs have been fabricated in various forms to perform tissue engineering to repair liver, bone, cartilage, heart tissues, cardiovascular tissues, bone marrow, and to act as drug delivery system and nerve conduits. A large number of animal trials have been carried out to assess the biomedical properties of PHA monomers, which also confirms the high compatibility of PHA family for this field. This review summarizes the synthesis of PHA from different sources, and biosynthetic pathways and biomedical applications of biosynthesized polyhydroxyalkanoates.
In this article, a unique metamaterial (MTM) structure is presented that exhibits four resonances of transmission coefficient (S21) that fall into S, X, and Ku bands. The MTM design is initiated on a Rogers (RT5880) substrate with an electrical dimension of 0.088 λ × 0.088 λ (λ is calculated at 3.424 GHz). The resonating patch contains four quartiles connected by a central metallic strip. The placement of each quartile is such that the whole resonator is mirror symmetric about the vertical axis. Two H-shaped modifiers connect two quartiles of each vertical half of the resonator. These H-shaped modifiers form the resonance cavity in its vicinity, and thus help significantly to orient the overall resonances of the proposed MTM at 3.424 GHz, 10 GHz, 14.816 GHz, and 16.848 GHz. The resonance phenomena are examined through equivalent circuit modeling and verified in Advanced Design Software (ADS). Metamaterial properties of the proposed MTM are extracted and it exhibits negative permittivity, permeability, and refractive index. The prototype of the MTM is fabricated and measurement is taken. The measured S21 shows a close similarity with the simulated result. Moreover, effective medium ratio (EMR) is calculated for the proposed MTM and a high EMR of 10.95 is obtained that expresses its compactness. This compact MTM with negative permittivity, permittivity, and refractive index can be important component for improving the performance of the miniaturized devices for multi-band wireless communication systems.