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Chitosan is a good adsorbent but has poor effectiveness against some dyes. Therefore, in this study, we synthesized composite materials of prepared crab shell chitosan with ZnO and PVA to improve adsorption efficiency. The ZnO/CTS and ZnO/PVA/CTS composites were synthesized by dissolving the components into a solution with the help of ultrasound and hydrothermally neutralizing it for 3 h. The obtained composites and crab shell chitosan were characterized by methods such as GPC, FTIR, XRD, and SEM. Adsorption experiments were conducted in batch form and only sampled once under each condition. The results showed the molecular weight of crab shell chitosan is around 105 g/mol and quite homogenous in size, and the embedded nanorod-like ZnO in the composite is around 200 nm in sizes. The adsorption of the dyes Indigo Carmine (IC), Alizarin Yellow (AY), and Thymol Blue (TB) onto the composites was highest compared to the single adsorbent and ranked in descending order: ZnO/CTS+AY > ZnO/PVA/CTS+IC > ZnO/CTS+IC > ZnO/PVA/CTS+AY > ZnO/CTS+TB > ZnO/PVA/CTS+TB, which corresponds to qmax of 285.7 mg/g, 227.3 mg/g, 208.3 mg/g, 188.7 mg/g, 60.6 mg/g, and 50.3 mg/g, respectively. In addition, the adsorption kinetics of all cases followed the pseudo-second-order adsorption model, it implies that the rate of adsorption is proportional to the square of the number of unoccupied sites. [ABSTRACT FROM AUTHOR]

An assessment of varying density, species composition and dynamics of phytoplankton in a combined rice-shrimp culture was carried out in My Xuyen district, Soc Trang province in the Vietnamese Mekong delta. Water was sampled six times at six separate locations within the culture system, on days 1, 20, 34, 57, 68, and day 81 of the rice-shrimp crop cycle. The results showed the abundance of 95 phytoplankton species belonging to five phyla including Cyanophyta, Chlorophyta, Bacillariophyta, Euglenophyta, and Pyrrophyta. The values of Shannon–Wiener index indicated high phytoplankton diversity, while the water quality ranged from medium to good. A Cluster Analysis showed that the phytoplankton density variation can be divided into three distinct periods. The initial phase of crop growth was dominated by Pandorina morum, Pediastrum simplex, Eudorina elegans, Oscillatoria limosa, and Anabaena circinalis. The midstage, reproductive phase of crop growth was dominated by Scenedesnus acuminatus, Pediastrum duplex, Closterinm setaceum, Scenedesnus quadricauda, and Actinastnum hantzschii. Whereas Scenedesnus acuminatus, Scenedesnus quadricauda, Closterinm closterioides, Staurastrum arcuatum, Euglena nhrenbergii, and Phacus lnsmorensis were dominant at the end of crop cycle. The findings provide useful information on phytoplankton assemblages in a typical rice-shrimp culture, which has recently gained popularity as an adaptive livelihood system.

The rapid progress in the fields of biomedical and biological photonic sciences has given rise to a substantial demand for biological photonic structures capable of interacting with living systems. These structures are expected to facilitate precise manipulation of incident light at small scales, enabling the detection of sensitive biological signals and the achievement of highly accurate cell structural imaging. The concept of designing biological photonic devices using innate biomaterials, particularly natural entities such as cells, viruses, and organs, has gained prominence. These innovative devices offer the capability of multimodal light manipulation at specific sites, enhancing biological compatibility while minimizing disruptions to the delicate biological microenvironment. This article delves into recent advancements within the realm of biological photonic devices, with a dedicated focus on their applications in bio-imaging and -diagnosis. The central theme revolves around devices derived from biological entities possessing the requisite optical properties, biocompatibility, biofunctionality, and the ability to induce biological effects. These devices encompass a diverse range of optical functionalities, including light generation, transportation, and modulation, all of which play pivotal roles in bio-detection and imaging, thereby contributing notably to the advancement of these fields. The potential future directions and opportunities for the enhancement of biological photonic devices were outlined. [ABSTRACT FROM AUTHOR]

Besides photocatalysts, novel catalytic wet-air oxidation (CWAO) catalysts capable of operating under mild conditions are a potential candidate to fabricate antifouling filtration membranes. This study optimized the CWAO catalyst consisting of three metal oxide components (ZnO, CuO, and Fe3O4) and used it to fabricate composite membranes with PES (polyethersulfone). The catalyst was characterized by methods such as FTIR, BET, XRD, UV-Vis DRS, XPS, ESR. The activity of the catalyst and the composite membranes was tested by the Acid Yellow 42 (AY42) degradation experiments in both cases with and without hydrogen peroxide at room conditions with air aeration. The pure water fluxes of composite membranes were also investigated based on a vacuum filtration system. The major degradation pathways of AY42 by the catalyst were proposed from the DFT (Density Functional Theory) and NBO (Natural Bond Orbital) calculations. The results showed that the optimal catalyst has molar ratios of Zn, Cu, and Fe metal ions of 0.05, 0.588, and 0.362, respectively, with AY42 decomposition efficiency of 88% in 3 h. The main factors affecting the catalytic efficiency of the CWAO catalyst determined from the trapping experiment were e– and O2. The results from different materials characterization methods have demonstrated the successful synthesis of the catalyst with a high surface area (103.5 m2/g) and small pore diameters (∼10 nm). The AY42 degradation of composite membranes was stable over five repeated cycles with over 70% efficiency. The pure water fluxes of composite membranes have also been significantly improved and are proportional to catalyst contents. [ABSTRACT FROM AUTHOR]

Because of the small size effect leading to the high bandgap of TiO2 P25, the photocatalytic membrane using this photocatalyst has low antifouling efficiency. This study prepared CuO@TiO2 composite photocatalyst with a lower bandgap than TiO2 P25 and used it as antifouling coatings on the PES membrane with PAA intermediate adhesive layer. PAA was grafted onto the surface of the PES membranes through free radicals generated by the cold plasma treatment of the PES membrane. The composite photocatalysts were characterized by FTIR, SEM–EDS, TEM-EDS, XRD, BET, UV–Vis DRS, XPS, and ESR methods demonstrating high surface area (51.0 m2/g), decreased bandgap, and the formation of active free radicals under UV light irradiation. Under photocatalysis and hydrogen peroxide activation, the degradation of AB260 (acid blue 260) catalyzed by 10%CuO@TiO2 reached about 92% after 60 min. Besides, the photocatalytic and antifouling activities of CuO@TiO2/PAA/PES membranes are high and stable over five continuous cycles. The water flux of the modified membrane was not significantly influenced and only decreased about 10% compared to the pristine membrane. In addition, the flux recovery ratios (FRR) of fouled membranes treated by photocatalysis were almost 100%. [ABSTRACT FROM AUTHOR]

The combination of conventional organic membranes and photocatalysts has led to an extensively studied field that is so-called photocatalyst modified membranes with antifouling, self-cleaning properties under UV or visible light irradiation. However, most of the research is limited to laboratory scale and artificial experimental conditions because this field still faces obstacles to practical applications. The main problems are the stability of these photocatalytic membranes or the binding between the photocatalysts and the membranes, and the low antifouling performance under visible light irradiation. Therefore, photocatalyst designs, membrane modification and fabrication methods are the key factors determining the success or failure of these photocatalytic membranes in water and wastewater filtration and separation processes. In this review, various types of photocatalyst incorporation into polymeric membranes were discussed, including the long-term stability, the organic pollutants' degradation efficiency, and the antifouling, self-cleaning performance of photocatalytic membranes. In addition, the mechanisms of membrane fouling and antifouling, membrane classifications, and fabrication methods were also discussed. [ABSTRACT FROM AUTHOR]

Presently, most of the population has been facing a string of severe air pollution problems that include the intensive emission of nitric oxide (NO), which requires a practical approach to sustain our living conditions. Herein, Ag nanoparticles (Ag NPs)-decorated ZnSn(OH)6 microcubes (Ag:cZHS) photocatalysts are synthesized and used for photocatalytic NO removal under solar light activation. The properties of the newly obtained photocatalysts are comprehensively characterized by a series of typical methods. The NO removal performance over the c:ZHS photocatalysts was increased markedly upon being combined with Ag NPs because of the surface plasmon resonance effect. The contribution of electron (e−), hole (h+), hydroxyl radical (•OH), and oxygen radicals (•O2) was investigated through trapping tests and electron spin resonance analysis. Also, the by-products and apparent quantum efficiency of the photocatalysts were thoroughly studied. [ABSTRACT FROM AUTHOR]

Mineralization of scaffolds is essential for alveolar ridge preservation and bone tissue engineering, enhancing the mechanical strength and bioactivity of scaffolds, and promoting better integration with natural bone tissue. While the in situ mineralization method using concentrated SBF solutions is promising, there is limited comprehensive research on its effects. In this study, it is demonstrate that soaking gelatin/alginate scaffolds (GAS) in fivefold concentrated SBF significantly reduces the mineralization time to 3-7 days but also leads to considerable degradation and loss of the scaffold's original microstructure. The ratio of gelatin to alginate is optimized to improve the properties of GAS. The optimized GAS sample, when soaked in concentrated SBF to form GAS/HAp, exhibited hydroxyapatite (HAp) crystal formation starting from day 3, with mature hexagonal crystals forming by day 7. However, this process also caused significant decomposition and deformation of the scaffold's pore structure. Additionally, the biocompatibility of GAS and GAS/HAp is evaluated through in vitro, in ovo, haemolysis, and anti-ROS assays. The findings highlight the impact of SBF 5× on the mineralization of GAS, laying the groundwork for further research in alveolar ridge preservation and bone tissue engineering., (© 2024 Wiley‐VCH GmbH.)

Combination therapy based on precise phototherapies combined with immune modulation provides successful antitumor effects. In this study, a combination therapy is designed based on phototactic, photosynthetic, and phototherapeutic Chlamydomonas Reinhardtii (CHL)-glycol chitosan (GCS)-polypyrrole (PPy) nanoparticle (NP)-enhanced immunity combined with the tumor microenvironment turnover of cytotoxic T cells and M1/M2 macrophages, which is based on photothermal GCS-PPy NPs decorated onto the phototactic and photosynthetic CHL. Phototherapy based on CHL-GCS-PPy NPs alleviates hypoxia and modulates the tumor immune microenvironment, which induces tumor cell death. In particular, the precise antitumor immune response and potent immune memory induced by combining self-navigated phototherapies significantly alleviate the progression of bladder cancer in C57BL/6 mice and effectively inhibit bladder tumor growth. Furthermore, they also potentially prevent tumor recurrence, which provides a promising therapeutic strategy for clinical tumor therapy., (© 2024 Wiley‐VCH GmbH.)