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Microplastics are commonly recognized as environmental and biotic contaminants. The prevalent presence of microplastics in aquatic settings raises concerns about plastic pollution. Therefore, it is critical to develop methods that can eliminate these microplastics with low cost and high effectiveness. This review concisely provides an overview of various methods and technologies for removing microplastics from wastewater and marine environments. Dynamic membranes and membrane bioreactors are effective in removing microplastics from wastewater. Chemical methods such as coagulation and sedimentation, electrocoagulation, and sol-gel reactions can also be used for microplastic removal. Biological methods such as the use of microorganisms and fungi are also effective for microplastic degradation. Advanced filtration technologies like a combination of membrane bioreactor and activated sludge method show high microplastic removal efficiency.

Water Purification is often an important methodological tool in low radioactivity experiments. A variety of techniques have been exploited in the frame of the Borexino experiment to the goal of using water as a high purity shielding and as a reagent for cleaning and purification processes. This paper describes the water purification strategies and the purification results obtained in Borexino.

Water purification is an important technique in high-mass low radioactivity experiments in modern physics. Water is frequently used both as a shielding and as the sensitive part of a particle detector in underground arrangements, especially in the frame of Astroparticle Physics studies. In this paper, I will describe the main purification techniques and discuss some of its performances.

Porous materials are promising candidates for the removal of organic pollutants from different water bodies. Among porous materials, cryogels are more attractive candidates due to their macro-porosity and rapid adsorption. This work evaluated the fabrication and adsorption capability of macro-porous Gum Arabic-based Cryogel. The fabricated Gum Arabic cryogel was modified and protonated to the protonated modified Gum Arabic Cryogel to compare its adsorption capacities for three different dyes. The successful fabrication of cryogel was confirmed by Fourier Transform Infrared spectroscopy, Differential Scanning Calorimetry, Thermal gravimetric analysis and Scanning Electron Microscopy. The protonated modified Gum Arabic Cryogel showed enhanced adsorption capability towards subjected dyes by following second-order rate kinetics. These cryogels can be employed as an efficient adsorbent to remove toxic contaminants from wastewater effluents.

Graphene oxide (GO) is an amphiphilic, water dispersible, chemical derivative of graphene. Widely used as a pathway to obtain graphene, it also has a number of interesting applications by itself due to its ability to form covalently and non-covalently bonded organic–inorganic hybrids and polymer composites. Thus, GO-based composites are used in numerous applications in membrane and coating technologies. It is important that due to the presence of functional acidic groups, GO possesses tunable physicochemical properties like a negatively charged polyelectrolyte and can be used as stimuli responsive membranes, membranes that can interact with environment and switch their properties on demand. Thus, ionic/molecular separation, water purification, selective sensing, and stimuli responsive properties have already been demonstrated in the laboratory. Good mechanical strength and conductivity (in its partially reduced form) make it attractive for the construction of the membranes for energy devices and sensors. However, concentration and distribution of the functional groups on GO molecules is difficult to control. It makes GO materials difficult to standardize, produce, and apply in industry. To this end, it is important to highlight recent achievement in the synthesis of GO as well as in design of GO-based energy devices, corrosion inhibiting coatings, and biomedical devices with improved working performances to evoke interest on mass production of GO with improved formulation.

Landmark Discovery of "Engine" that Drives Cell Movement.

Asia's First Palliative Care Research Center in Singapore.

Growing Green Technologies with Organic Photovoltaics.

Siemens Opens First Corporate Technology in South-east Asia at the PUB's Waterhub.

Singapore's First Reservoir in the City Embodies Water and Energy Renewal Directives.

New methods for water treatment are required as a result from an increasing awareness in the reduction of the pollution impact in the environment. In the perspective of the photo-oxidation of organic pollutants present in water, the principal incentive for the preparation of heterogeneous photocatalysts is their easy recovery from the reaction mixture, which allows their reuse in successive runs, minimizing the loss of their original photocatalytic properties. Different types of supports can be used in the immobilization of photoactive species, such as porphyrins (Pors) and phthalocyanines (Pcs). This mini-review will consider the different methodologies for the immobilization of Pors and Pcs and their photocatalytic performance in the photodegradation of organic pollutants in water, addressing also their recycling ability in successive water treatments.

Two-dimensional hexagonal boron nitride is a fascinating nanomaterial with a broad range of potential applications. However, further development of this nanomaterial is hampered because of its poor functionality and low processability. One of the efficient strategies for improving the processability of two-dimensional hexagonal boron nitride is the covalent functionalization of this nanomaterial. In this study, we report on a straightforward approach for functionalization of two-dimensional hexagonal boron nitride by lithium cyclopentadienyl and its application for water treatment. Cyclopentadienyl-functionalized boron nitride was characterized by different spectroscopy and microscopy methods as well as thermal and BET analysis. The synthesized nanomaterial was able to efficiently remove methylene blue from water in a short time. Adsorption capacity of this nanomaterial was as high as 476.3mg/g, which was superior to the nonfunctionalized boron nitride. Our results showed that cyclopentadienyl-functionalized boron nitride is a promising candidate for the removal of cationic pollutants from water.

Amorphous magnetic particles demonstrate excellent comprehensive properties and outstanding characteristics for numerous applications. In this report, magnetic crystalline Fe₃O₄ and amorphous Fe-B nanoparticles were successfully synthesized and introduced to prepare water-based magnetic fluids. The Fe₃O₄ and Fe-B particles are homogeneous nanoparticles with an average particle size of $12\sim 15$nm. The shape of Fe-B amorphous nanoparticles is regular. The saturation magnetizations of Fe-B and Fe₃O₄ particles are 74 emu/g and 69 emu/g. The use of crystalline Fe₃O₄ magnetic fluid and amorphous Fe-B magnetic fluid in advanced treatment of high concentration organic wastewater was presented. The removal rate of chemical oxygen demand by using the amorphous Fe-B magnetic fluid reached 96%, about 16% higher than that by using the Fe₃O₄ magnetic fluid. Moreover, compared with Fe₃O₄ magnetic fluid, the treatment results demonstrate that the decolorizing effect by using the amorphous Fe-B magnetic fluid was 20% higher. It has been found that the nano-size Fe-B particles in magnetic fluid with amorphous structure led to high efficiency of wastewater treatment due to the catalytic activity.

Humic acid (HA)-coated Fe₃O₄ (Fe₃O₄/HA) superparamagnetic nanoparticles were synthesized by a chemical co-precipitation method with cheap and environmental friendly iron salts and HA. The as-synthesized samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). The Fe₃O₄/HA nanoparticles showed faster adsorption rate and higher removal capacity of cationic organic dye Methylene blue (MB) in neutral water. Moreover, the MB desorption could be easily completed. And the reused performance of Fe₃O₄/HA nanoparticles was also excellent.

A novel, environmental-friendly approach for the reduction of graphene oxide (GO) by means of incorporating visible-light sensitive TiO₂ and steady state visible-light irradiation was undertaken. Some potential applications of the resultant TiO₂-graphene composites as water treatment technique, such as electrosorption and dissolved organic matter removal, have been demonstrated as well.

The adsorption of three kinds of azo dyes from aqueous solution on HKUST-1/graphene oxide (GO) composite was studied in view of the removal efficiency, adsorption isotherm, and regenerate of the sorbent. HKUST-1/GO was found to be with higher dyes removal efficiency than HKUST-1. All the adsorption isotherms of azo dyes on HKUST-1/GO composite followed Freundlich isotherm. The adsorbed azo dyes on HKUST-1/GO could be eluted by acetone, so HKUST-1/GO can also be used for enrichment of azo dyes as adsorbent.

Membrane technologies are essential for water treatment, bioprocessing and chemical manufacturing. Stimuli-responsive membranes respond to changes in feed conditions (e.g., temperature, pH) or external stimuli (e.g., magnetic field, light) with a change in performance parameters (permeability, selectivity). This enables new functionalities such as tunable performance, self-cleaning and smart-valve behavior. Polymer self-assembly is a crucial tool for manufacturing such membranes using scalable methods, enabling easier commercialization. This review surveys approaches to impart stimuli responsive behavior to membrane filters using polymer self-assembly.

We investigate household perceptions of water quality and associated averting behaviors using household survey data from León, Nicaragua. Seemingly unrelated instrumental variable probit models are estimated to take the potential endogeneity of water quality perceptions and the relationship between different averting behaviors into account. Survey results indicate that a large majority of households use tap water for drinking purposes. Less than 26% of sampled households implement in-home water treatments and about 33% of households consume bottled water. Results indicate that observed averting behaviors (i.e., consumption of bottled water and in-home water treatments), or lack thereof, are primarily driven by the perceived quality of tap water. Findings also indicate that perceptions of water quality are associated with service performance and assessment of water quality relative to peers. Policy implications are discussed.

After years of attempting to address rising turbidity in its water supplies with engineering solutions, Vitória, the capital of the Brazilian state of Espírito Santo, is turning to watershed conservation. Degradation in the watershed of the Santa Maria da Vitória River, from which Vitória obtains almost 40% of its water supplies, has resulted in a significant increase in water treatment costs; investments in improved filtration have only managed to slow. To reduce erosion in the watershed, a program of Payments for Environmental Services (PES) is being implemented, initially in a micro-watershed that has been identified as contributing disproportionately to sediment loads. This paper estimates the impact of watershed degradation on Vitória’s water treatment costs and undertakes a cost–benefit analysis of the benefits of watershed conservation. These interventions will benefit both downstream water users, in the form of lower water treatment costs, and upstream landholders, in the form of higher income from farming activities and payments for conservation.

Water quality remains a significant issue and a source of serious health concern in the developing world. This paper investigates the water averting behavior at the household level by using a primary survey data from Siddharthangar, Nepal. While past studies have generally attributed averting behaviors to risk perception, we place a particular emphasis on the divergence between the household’s perception of their drinking water quality and the actual water quality level in driving the averting behavior. The findings indicate that the perception of the water quality affects a household’s decision to employ water treatment measures. Households that considered their water to be safe were less likely to treat their water. Furthermore, in addition to perception, the result also suggests the deviation between actual and perceived water quality level could also be a crucial element in the decision to employ water treatment measures. Households with divergence between risk perception and the objective water quality levels were less likely to treat their water and this result held across different specifications. In contrast, households with minimal deviation were more likely to employ treatment measures. Findings also suggest the source of drinking water, education level, income and the taste of the drinking water also drives the averting behavior.

Forests are widely believed to provide a water purification service that reduces the cost of treating drinking water, but few empirical economic studies have investigated this service in developing countries, where deforestation rates and thus threats to the service tend to be higher than in developed countries. Even fewer studies have investigated the distribution of the benefits of this service, or any other regulating ecosystem service for that matter, in either developing or developed countries. Using quarterly panel data for 158 water utilities in Thailand during 2004–2014, we find robust evidence that forests significantly reduced the material cost of water treatment, but we find no evidence that the cost reductions were progressive in the sense of being larger in provinces with higher poverty rates. The economic justification for source water protection in Thailand appears to hinge purely on considerations of efficiency — does source water protection provide net benefits? — not on the distribution of those benefits between poorer and richer locations. Research in other countries is needed to determine if the absence of pro-poor distributional impacts of forest water purification is unique to Thailand or the norm and if interventions that enhance forest water purification significantly reduce poverty in locations served by treated drinking water systems.

Graphene oxide (GO) is an amphiphilic, water dispersible, chemical derivative of graphene. Widely used as a pathway to obtain graphene, it also has a number of interesting applications by itself due to its ability to form covalently and non-covalently bonded organic–inorganic hybrids and polymer composites. Thus, GO-based composites are used in numerous applications in membrane and coating technologies. It is important that due to the presence of functional acidic groups, GO possesses tunable physicochemical properties like a negatively charged polyelectrolyte and can be used as stimuli responsive membranes, membranes that can interact with environment and switch their properties on demand. Thus, ionic/ molecular separation, water purification, selective sensing, and stimuli responsive properties have already been demonstrated in the laboratory. Good mechanical strength and conductivity (in its partially reduced form) make it attractive for the construction of the membranes for energy devices and sensors. However, concentration and distribution of the functional groups on GO molecules is difficult to control. It makes GO materials difficult to standardize, produce, and apply in industry. To this end, it is important to highlight recent achievement in the synthesis of GO as well as in design of GO-based energy devices, corrosion inhibiting coatings, and biomedical devices with improved working performances to evoke interest on mass production of GO with improved formulation.

Microplastics are commonly recognized as environmental and biotic contaminants. The prevalent presence of microplastics in aquatic settings raises concerns about plastic pollution. Therefore, it is critical to develop methods that can eliminate these microplastics with low cost and high effectiveness. This review concisely provides an overview of various methods and technologies for removing microplastics from wastewater and marine environments. Dynamic membranes and membrane bioreactors are effective in removing microplastics from wastewater. Chemical methods such as coagulation and sedimentation, electrocoagulation, and sol-gel reactions can also be used for microplastic removal. Biological methods such as the use of microorganisms and fungi are also effective for microplastic degradation. Advanced filtration technologies like a combination of membrane bioreactor and activated sludge method show high microplastic removal efficiency.

Now mechanical water treatment technology is getting wide use gradually. This new technology is changing the work way of conventional water plants in practice. In the process of water treatment, the filter process is a very important step. In this paper, the strength and deformation of upper filter system which includes upper filter frames and upper filter plates were analyzed with ANSYS and useful results are got. Finally, according to the analysis results, the paper combined theory with practice, pointed out the disadvantage of design and provided the optimized advice about the upper filter system design.