A comprehensive review and perspective research in technology integration for the treatment of gaseous volatile organic compounds.

Volatile organic compounds (VOCs) are harmful pollutants emitted from industrial processes. They pose a risk to human health and ecosystems, even at low concentrations. Controlling VOCs is crucial for good air quality. This review aims to provide a comprehensive understanding of the various methods used for controlling VOC abatement. The advancement of mono-functional treatment techniques, including recovery such as absorption, adsorption, condensation, and membrane separation, and destruction-based methods such as natural degradation methods, advanced oxidation processes, and reduction methods were discussed. Among these methods, advanced oxidation processes are considered the most effective for removing toxic VOCs, despite some drawbacks such as costly chemicals, rigorous reaction conditions, and the formation of secondary chemicals. Standalone technologies are generally not sufficient and do not perform satisfactorily for the removal of hazardous air pollutants due to the generation of innocuous end products. However, every integration technique complements superiority and overcomes the challenges of standalone technologies. For instance, by using catalytic oxidation, catalytic ozonation, non-thermal plasma, and photocatalysis pretreatments, the amount of bioaerosols released from the bioreactor can be significantly reduced, leading to effective conversion rates for non-polar compounds, and opening new perspectives towards promising techniques with countless benefits. Interestingly, the three-stage processes have shown efficient decomposition performance for polar VOCs, excellent recoverability for nonpolar VOCs, and promising potential applications in atmospheric purification. Furthermore, the review also reports on the evolution of mathematical and artificial neural network modeling for VOC removal performance. The article critically analyzes the synergistic effects and advantages of integration. The authors hope that this article will be helpful in deciding on the appropriate strategy for controlling interested VOCs.

Phase Behavior of the Mixtures of 2- and 3-Components for Poly(styrene-co-octafluoropentyl methacrylate) by Dispersion Polymerization under CO2.

The dispersed-phase polymerization of poly(styrene-co-2,2,3,4,4,4-octafluoropentyl methacrylate), also known as p(styrene-co-OFPMA), took place in supercritical carbon dioxide (sc-CO2). The chemical and physical properties of p(styrene-co-OFPMA) were studied by varying the styrene-to-OFPMA ratios (40:1, 30:1, and 20:1) and 2,2'-azobis(isobutyronitrile) (AIBN) initiator amounts (wt %: 1.0, 2.0, 3.0). The cloud-point data were obtained for various systems, including the binary mixtures of p(styrene-co-OFPMA) (30:1 ratio, AIBN wt %: 1.0, 2.0, 3.0) with supercritical solvents such as sc-CO2, sc-CH3OCH3, sc-C3H6, sc-C4H8, and sc-CHClF2. Phase behavior (i.e., mixtures) was studied at temperatures of 324-455 K and pressure below 201 MPa. In the binary system of p(styrene-co-OFPMA) + sc-CH3OCH3, a lower critical solution temperature (LCST)-type curve was observed, characterized by a positive slope. Conversely, the binary systems of p(styrene-co-OFPMA) + (sc-C3H6, sc-C4H8, sc-CHClF2) exhibited an upper critical solution temperature (UCST) behavior with a decreasing slope. The phase equilibrium curves were obtained for p(styrene-co-OFPMA) [30:1; 1.0% (Mw = 42,400), 2.0% (Mw = 33,800), and 4.0% (Mw = 24,100); AIBN: 1.0 wt %] + sc-C3H6, sc-C4H8, and sc-CHClF2 mixtures. These curves exhibited an increasing slope for p(styrene-co-OFPMA) + sc-CH3OCH3 and a negative slope for p(styrene-co-OFPMA) + (sc-C3H6, sc-C4H8, sc-CHClF2) systems, indicating distinct phase behavior. Tetramethyl orthosilicate (TMOS) addition (0.0-68.9 wt %) to P(styrene-co-OFPMA) (30:1; AIBN wt %: 1.0) + solvents altered the phase equilibrium, switching from UCST to LCST, as evidenced by changes in the pressure-temperature slope.

Nanoemulsion as an Effective Inhibitor of Biofilm-forming Bacterial Associated Drug Resistance: An Insight into COVID Based Nosocomial Infections.

Antibiotic overuse has resulted in the microevolution of drug-tolerant bacteria. Understandably it has become one of the most significant obstacles of the current century for scientists and researchers to overcome. Bacteria have a tendency to form biofilm as a survival mechanism. Biofilm producing microorganism become far more resistant to antimicrobial agents and their tolerance to drugs also increases. Prevention of biofilm development and curbing the virulency factors of these multi drug resistant or tolerant bacterial pathogens is a newly recognised tactic for overcoming the challenges associated with such bacterial infections and has become a niche to be addressed. In order to inhibit virulence and biofilm from planktonic bacteria such as, Pseudomonas aeruginosa, Acinetobacter baumannii, and others, stable nanoemulsions (NEs) of essential oils (EOs) and their bioactive compounds prove to be an interesting solution. These NEs demonstrated significantly greater anti-biofilm and anti-virulence activity than commercial antibiotics. The EO reduces disease-causing gene expression, which is required for pathogenicity, biofilm formation and attachment to the surfaces. Essential NE and NE-loaded hydrogel surface coatings demonstrates superior antibiofilm activity which can be employed in healthcare-related equipments like glass, plastic, and metal chairs, hospital beds, ventilators, catheters, and tools used in intensive care units. Thus, anti-virulence and anti-biofilm forming strategies based on NEs-loaded hydrogel may be used as coatings to combat biofilm-mediated infection on solid surfaces.

Stretchable, Implantable, Nanostructured Flow-Diverter System for Quantification of Intra-aneurysmal Hemodynamics.

Random weakening of an intracranial blood vessel results in abnormal blood flow into an aneurysmal sac. Recent advancements show that an implantable flow diverter, integrated with a medical stent, enables a highly effective treatment of cerebral aneurysms by guiding blood flow into the normal vessel path. None of such treatment systems, however, offers post-treatment monitoring to assess the progress of sac occlusion. Therefore, physicians rely heavily on either angiography or magnetic resonance imaging. Both methods require a dedicated facility with sophisticated equipment settings and time-consuming, cumbersome procedures. In this paper, we introduce an implantable, stretchable, nanostructured flow-sensor system for quantification of intra-aneurysmal hemodynamics. The open-mesh membrane device is capable of effective implantation in complex neurovascular vessels with extreme stretchability (500% radial stretching) and bendability (180° with 0.75 mm radius of curvature) for monitoring of the treatment progress. A collection of quantitative mechanics, fluid dynamics, and experimental studies establish the fundamental aspects of design criteria for a highly compliant, implantable device. Hemocompatibility study using fresh ovine blood captures the device feasibility for long-term insertion in a blood vessel, showing less platelet deposition compared to that in existing implantable materials. In vitro demonstrations of three types of flow sensors show quantification of intra-aneurysmal blood flow in a pig aorta and the capability of observation of aneurysm treatment with a great sensitivity (detection limit as small as 0.032 m/s). Overall, this work describes a mechanically soft flow-diverter system that offers an effective treatment of aneurysms with an active monitoring of intra-aneurysmal hemodynamics.

Wireless, intraoral hybrid electronics for real-time quantification of sodium intake toward hypertension management.

Recent wearable devices offer portable monitoring of biopotentials, heart rate, or physical activity, allowing for active management of human health and wellness. Such systems can be inserted in the oral cavity for measuring food intake in regard to controlling eating behavior, directly related to diseases such as hypertension, diabetes, and obesity. However, existing devices using plastic circuit boards and rigid sensors are not ideal for oral insertion. A user-comfortable system for the oral cavity requires an ultrathin, low-profile, and soft electronic platform along with miniaturized sensors. Here, we introduce a stretchable hybrid electronic system that has an exceptionally small form factor, enabling a long-range wireless monitoring of sodium intake. Computational study of flexible mechanics and soft materials provides fundamental aspects of key design factors for a tissue-friendly configuration, incorporating a stretchable circuit and sensor. Analytical calculation and experimental study enables reliable wireless circuitry that accommodates dynamic mechanical stress. Systematic in vitro modeling characterizes the functionality of a sodium sensor in the electronics. In vivo demonstration with human subjects captures the device feasibility for real-time quantification of sodium intake, which can be used to manage hypertension.

Mechanical and water barrier properties of starch/PVA composite films by adding nano-sized poly(methyl methacrylate-co-acrylamide) particles.

The aim of this work is to prepare starch/PVA composite films added nano-sized poly(methyl methacrylate-co-acrylamide) (PMMA-co-AAm) particles and to investigate the mechanical properties, water barrier properties, and soil burial degradation for the films. Composite films were prepared by using corn starch, polyvinyl alcohol (PVA), nano-sized PMMA-co-AAm particles, and additives, i.e., glycerol (GL), xylitol (XL), and citric acid (CA). Nano-sized PMMA-co-AAm particles were synthesized by emulsion polymerization. The results of the evaluation of properties for prepared films indicated that compared with films without PMMA-co-AAm particles, the mechanical properties and water resistance were improved up to 70-400% by the addition of nano-sized PMMA-co-AAm. In addition, the results of the soil burial biodegradation revealed that films added PMMA-co-AAm particles were degraded by about 45-65% after 165 days.

Physical properties and characterization of biodegradable films using nano-sized TiO2/poly(acrylamide-co-methyl methacrylate) composite.

In this study, biodegradable films were prepared by using corn starch, PVA, nano-sized poly(acrylamide-co-methyl methacrylate) (PAAm-co-MMA), nano-sized TiO2(P-25)/PAAm-co-MMA composite, and additives which are harmless to the human body, that is, glycerol (GL) and citric acid (CA). Nano-sized PAAm-co-MMA was synthesized by the method of emulsion polymerization. Also, nano-sized TiO2/PAAm-co-MMA composites were synthesized by wet milling for 48 h. The morphology and crystallinty of nano-sized PAAm-co-MMA and TiO2/PAAm-co-MMA composite was observed by the SEM and XRD. The physical properties such as tensile strength (TS), elongation at break (%E), degree of swelling (DS), and solubility (S) of biodegradable films were investigated. The photocatalytic degradability of starch/PVA/nano-sized TiO2/PAAm-co-MMA composite blended films was evaluated using methylene blue as photodegradation target.