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1.
Proc Inst Mech Eng H ; : 9544119231188860, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37655850

RESUMO

Incontinence is a common health issue that affects hundreds of millions of people across the world. The solution is often to manage the condition with different kinds of single-use continence technologies, such as incontinence pads and other absorbent hygiene products (AHPs). Throughout their life cycle, these fossil-based products form a remarkable yet inadequately addressed ecological burden in society, contributing to global warming and other environmental degradation. The products are a necessity for their users' wellbeing. When looking for sustainability transitions in this field, focus on individual consumer-choice is thus inadequate - and unfair to the users. The industry is already seeking to decrease its carbon footprint. Yet, to tackle the environmental impact of single-use continence products, also societies and health systems at large must start taking continence seriously. Arguing that continence-aware societies are more sustainable societies, we devise in this article a society-wide working definition for holistically sustainable continence care. Involving dimensions of social, ecological and economic sustainability, the concept draws attention to the wide range of technologies, infrastructures and care practices that emerge around populations' continence needs. Holistically sustainable continence care is thus not only about AHPs. However, in this article, we examine holistically sustainable continence care through the case of AHPs. We review what is known about the environmental impact AHPs, discuss the impact of care practices on aggregate material usage, the future of biobased and degradable incontinence pads, as well as questions of waste management and circular economy. The case of AHPs shows how holistically sustainable continence care is a wider question than technological product development. In the end of the article, we envision an ecosystem where technologies, infrastructures and practices of holistically sustainable continence care can flourish, beyond the focus on singular technologies.

2.
Phys Chem Chem Phys ; 25(34): 22870-22888, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37587837

RESUMO

In this paper, a benzyltriethylammonium/urea DES was investigated as a new green and eco-friendly medium for the progress of organic chemical reactions, particularly the dissolution and the functionalization of cellulose. In this regard, the viscosity-average molecular weight of cellulose (M̄w) during the dissolution/regeneration process was investigated, showing no significant degradation of the polymer chains. Moreover, X-ray diffraction patterns indicated that the cellulose dissolution process in the BTEAB/urea DES decreased the crystallinity index from 87% to 75%, and there was no effect on type I cellulose polymorphism. However, a drastic impact of the cosolvents (water and DMSO) on the melting point of the DES was observed. Besides, to understand the evolution of cellulose-DES interactions, the formation mechanism of the system was studied in terms of H-bond density and radial distribution function (RDF) using molecular dynamics modeling. Furthermore, density functional theory (DFT) was used to evaluate the topological characteristics of the polymeric system such as potential energy density (PED), laplacian electron density (LED), energy density, and kinetic energy density (KED) at bond critical points (BCPs) between the cellulose and the DES. The quantum theory of atoms in molecules (AIM), Bader's quantum theory (BQT), and reduced density gradient (RDG) scatter plots have been exploited to estimate and locate non-covalent interactions (NCIs). The results revealed that the dissolution process is attributed to the physical interactions, mainly the strong H-bond interactions.

3.
Polymers (Basel) ; 15(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679322

RESUMO

Textile single-use products are dominantly used for hygiene and personal care, many of which are non-biodegradable and are frequently discarded into sewerage systems, thus causing blockages. Thus, there is a need to move towards water-soluble textiles. This research study focuses on transforming or repurposing biomass material and synthetic reusable waste plastic materials to improve waste. Chitosan (CS) nanofibers could be used in single-use nonwoven fabric or biodegradable tissues, as the water-soluble properties of chitosan nanofibers make them the perfect material for single-use applications. Furthermore, CS was blended with polyethylene terephthalate (PET) polymer and PET-based waste plastic (CS-WPET) to slow the CS nanofibers' water degradability and strengthen the durability of the nanofiber which could be used as air filters. The CS-TFA and CS-TFA/DCM nanofiber diameters were 95.58 ± 39.28 nm or 907.94 ± 290.18 nm, respectively, as measured from the HRSEM images. The CS-PET and CS-WPET hybrid nanofibers had fiber diameters of 246.13 ± 96.36 or 58.99 ± 20.40 nm, respectively. The thermal durability of the nanofibers was tested by TGA, which showed that CS-TFA/DCM nanofibers had sufficient thermal stability up to 150 °C, making them suitable for filter or fabric use at moderate temperatures. The blended nanofibers (CS-PET and CS-WPET) were thermally stable up to 160 °C. In the aqueous medium stability test, CS-PET and CS-WPET hybrid nanofibers had a slower degradation rate and were easily dissolved, while the CS nanofibers were rapidly and completely dissolved in an aqueous medium. Blending waste PET with CS allows it to be recycled into a useful single-use, non-woven textile, with greater water solubility than unmodified PET nanofibers but more durability than CS nanofibers on their own.

4.
Euro Surveill ; 27(11)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35301980

RESUMO

BackgroundThe shortage of FFP2 and FFP3 respirators posed a serious threat to the operation of the healthcare system at the onset of the COVID-19 pandemic.AimOur aim was to develop and validate a large-scale facility that uses hydrogen peroxide vapour for the decontamination of used respirators.MethodsA multidisciplinary and multisectoral ad hoc group of experts representing various organisations was assembled to implement the collection and transport of used FFP2 and FFP3 respirators from hospitals covering 86% of the Finnish population. A large-scale decontamination facility using hydrogen peroxide vapour was designed and constructed. Microbiological tests were used to confirm efficacy of hydrogen peroxide vapour decontamination together with a test to assess the effect of decontamination on the filtering efficacy and fit of respirators. Bacterial and fungal growth in stored respirators was determined by standard methods.ResultsLarge-scale hydrogen peroxide vapour decontamination of a range of FFP2 and FFP3 respirator models effectively reduced the recovery of biological indicators: Geobacillus stearothermophilus and Bacillus atrophaeus spores, as well as model virus bacteriophage MS2. The filtering efficacy and facial fit after hydrogen peroxide vapour decontamination were not affected by the process. Microbial growth in the hydrogen peroxide vapour-treated respirators indicated appropriate microbial cleanliness.ConclusionsLarge-scale hydrogen peroxide vapour decontamination was validated. After effective decontamination, no significant changes in the key properties of the respirators were detected. European Union regulations should incorporate a facilitated pathway to allow reuse of appropriately decontaminated respirators in a severe pandemic when unused respirators are not available.


Assuntos
COVID-19 , Peróxido de Hidrogênio , Descontaminação/métodos , Finlândia , Humanos , Peróxido de Hidrogênio/farmacologia , Pandemias , Ventiladores Mecânicos
5.
Nurs Rep ; 11(3): 615-628, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34968337

RESUMO

A universal mask use was instituted in healthcare during COVID-19 pandemic in 2020. The extensive growth in the consumption of surgical masks and respirators brought new challenges. Healthcare workers had to get accustomed to wearing the facemasks continuously, raising concerns on the patient, occupational, and environmental safety. The aim of this study is to describe frontline healthcare workers and other authorities' views and experiences on continuous use of surgical masks and respirators (facemasks) and their attitudes towards environmental and sustainability issues. A cross-sectional web-based survey was conducted in Finland during the COVID-19 pandemic in autumn 2020. The respondents(N = 120) were recruited via social media, and the data were collected using a purpose-designed questionnaire. Descriptive statistics and inductive content analysis were used to analyze the quantitative data and qualitative data, respectively. The healthcare workers perceived their own and patient safety, and comfortability of facemasks as important, but according to their experiences, these properties were not evident with the current facemasks. They considered protection properties more important than environmental values. However, biodegradability and biobased material were seen as desired properties in facemasks. Based on the results, the current facemasks do not meet users' expectations well enough. Especially the design, breathability, and sustainability issues should be taken more into account.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33578670

RESUMO

Persistent pharmaceutical pollutants (PPPs) have been identified as potential endocrine disruptors that mimic growth hormones when consumed at nanogram per litre to microgram per litre concentrations. Their occurrence in potable water remains a great threat to human health. Different conventional technologies developed for their removal from wastewater have failed to achieve complete mineralisation. Advanced oxidation technologies such as dielectric barrier discharges (DBDs) based on free radical mechanisms have been identified to completely decompose PPPs. Due to the existence of pharmaceuticals as mixtures in wastewater and the recalcitrance of their degradation intermediate by-products, no single advanced oxidation technology has been able to eliminate pharmaceutical xenobiotics. This review paper provides an update on the sources, occurrence, and types of pharmaceuticals in wastewater by emphasising different DBD configurations previously and currently utilised for pharmaceuticals degradation under different experimental conditions. The performance of the DBD geometries was evaluated considering various factors including treatment time, initial concentration, half-life time, degradation efficiency and the energy yield (G50) required to degrade half of the pollutant concentration. The review showed that the efficacy of the DBD systems on the removal of pharmaceutical compounds depends not only on these parameters but also on the nature/type of the pollutant.


Assuntos
Disruptores Endócrinos , Preparações Farmacêuticas , Poluentes Químicos da Água , Purificação da Água , Disruptores Endócrinos/análise , Humanos , Águas Residuárias , Água , Poluentes Químicos da Água/análise
7.
Front Chem ; 8: 655, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062631

RESUMO

Poly(vinyl alcohol) (PVA) hydrogels produced using the freeze-thaw method have attracted attention for a long time since their first preparation in 1975. Due to the importance of polymer intrinsic features and the advantages associated with them, they are very suitable for biomedical applications such as tissue engineering and drug delivery systems. On the other hand, there is an increasing interest in the use of biobased additives such as cellulose nanocrystals, CNC. This study focused on composite hydrogels which were produced by using different concentrations of PVA (5 and 10%) and CNC (1 and 10 wt.%), also, pure PVA hydrogels were used as references. The main goal was to determine the impact of both components on mechanical, thermal, and water absorption properties of composite hydrogels as well as on morphology and initial water content. It was found that PVA had a dominating effect on all hydrogels. The effect of the CNC addition was both concentration-dependent and case-dependent. As a general trend, addition of CNC decreased the water content of the prepared hydrogels, decreased the crystallinity of the PVA, and increased the hydrogels compression modulus and strength to some extent. The performance of composite hydrogels in a cyclic compression test was studied; the hydrogel with low PVA (5) and high CNC (10) content showed totally reversible behavior after 10 cycles.

8.
J Fluoresc ; 29(4): 933-943, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31300981

RESUMO

Two new chemosensors for lead (II) were synthesized based on 5-((anthracen-9-ylmethylene) amino)quinolin-10-ol (ANQ). ANQ was modified in the para position of the imine group via a methoxy link either with methylmethacrylate (ANQ-MMA) or styrene (ANQ-ST). Complexation of those molecules with Pb2+ was studied at room temperature using UV-Visible absorption and fluorescence spectroscopies. Thanks to the UV-visible absorption spectroscopy, it appeared that ANQ-MMA formed 1:1 and 1:2 complexes with lead (II) and ANQ-ST only 1:1 complex. For both molecules, the fluorescence excitation-emission matrices (EEM) signal intensity increased from 0 to 100 µmol.L-1 of lead (II) followed by a saturation for higher concentrations. The decomposition of the obtained EEMs gave a set of empiric fluorescent components that have been directly linked to the distribution of lead complexes obtained with the UV-visible absorption spectroscopy study. This correlation allowed to evidence metal/ligand complex stoichiometry and emerge as a new method to identify empiric components. Moreover, the two ligands showed a promising selectivity for Pb2+, turning them interesting probes for this hazardous metal.

9.
J Colloid Interface Sci ; 448: 473-81, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25771289

RESUMO

Three novel Ni(II)-Ion-Imprinted Polymer (IIP) were synthesized by precipitation polymerization of ethylene glycol dimethacrylate (crosslinker) with a complex of nickel(II) and vinylbenzyl iminodiacetic acid (VbIDA). The three IIPs were prepared with various mixtures of porogen solvents: methanol, methanol/2-methoxyethanol and methanol/acetonitrile (IIP1, IIP2 and IIP3, respectively). Non-Imprinted Polymers (NIP1, NIP2 and NIP3) were prepared as control polymers in similar conditions but with pure VbIDA instead of VbIDA-Ni. These polymers were characterized by FTIR, BET, SEM and tested for their efficiency and selectivity in Ni(II) retention. The most efficient (IIP1, around 12 mg g(-1) of nickel) was then positively checked for Ni(II) retention in presence of some competing species over a wide range of concentration. Finally Ni(II) retention by IIP1 was successfully demonstrated in natural samples. The modelling of the different experiments (Langmuir, Freundlich but also PROSECE and WHAM VII, frequently used in environmental studies) allowed demonstrating the presence of completely different binding sites when considering the ion-imprinted polymer and the non-imprinted one, and therefore led to a better understanding of what the imprinting effect is.

10.
Talanta ; 134: 538-545, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25618705

RESUMO

In order to highlight the importance of the complex stoichiometry during ion imprinted polymer (IIP) synthesis, we investigated the effect of the complex structure on IIPs selectivity by adjusting the complex stoichiometry before polymerization. 2-(aminomethyl)pyridine monomer (amp) was chosen as a functionalized ligand for nickel(II) ions and a polymerizable vinylbenzyl derivative (Vbamp) was prepared. Complex formation was studied by varying the nickel/Vbamp ratio and recording absorption spectra of the complexes at the polymerization conditions. Using a least-squares minimization scheme, the complex species distribution was successfully established. From these results, it was possible to choose the metal/ligand stoichiometry in the complex (1:1; 1:2 or 1:3) by adjusting the initial metal/ligand ratio. IIPs were then prepared by inverse suspension copolymerization of Vbamp with ethyleneglycol dimethacrylate (EDMA). Highly porous particles with good nickel binding capacity and good Ni/Zn selectivity even at acidic conditions were obtained. Equilibrium uptake of Ni(II) at pH 7 ranged from 0.12 to 0.2 mmol g(-1) and relative selective coefficient was as high as 260 for the IIP prepared using the Ni(Vbamp)2 complex.

11.
J Hazard Mater ; 180(1-3): 234-40, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20435412

RESUMO

The selectivity of nanoporous manganese oxides for some alkali and transition metals over calcium and magnesium was studied. Two tunnel-structured oxides (OMS-1 and OMS-2) were synthesized by means of a hydrothermal route. Competitive uptake of metals and acid was studied using batch kinetic measurements at different metal ion concentrations. The experimental data were correlated with a dynamic model. The results show that the studied OMS materials selectively adsorb Cu, Ni and Cd in the presence of Ca and Mg. It was also found that the exchange rates were reasonably high due to the small particle dimensions. Both materials are stable in the studied conditions and their maximum Cu uptake capacity was 0.9-1.3 mmol/g. The results indicate that both materials have potential for environmental applications involving the uptake of harmful metal ions.


Assuntos
Cálcio/química , Conservação dos Recursos Naturais , Magnésio/química , Metais/química , Nanotecnologia , Adsorção , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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