The crucial role of transient tri-coordinated oxygen in the flow of silicate melts.

The transport properties of high-temperature silicate melts control magma flow and are crucial for a wide variety of industrial processes involving minerals. However, anomalous melt properties have been observed that cannot be explained by the traditional polymerization degree theory, which was derived based on quenched melts. Ab initio molecular dynamics (AIMD) simulations were conducted to investigate the flow mechanism of CaO-Al2O3-SiO2 melts under high temperature atmospheric conditions. By analyzing the dynamic structure of melted silicates and employing molecular orbital theory, we gained a fundamental understanding of the flow mechanism from a chemistry perspective. Transient tri-coordinated oxygen (TO) bonded with one Si and two Al atoms (SiOAl2) was found to be a pivotal intermediate in melt flow and atomic diffusion processes. Frequent chemical transition between TO in SiOAl2 and bridging oxygen (BO) dominated the fluidity of melted silicates. The presence of such transitions is facilitated by the unstable nature of [SiAlO2] 4-membered rings, which are susceptible to instability due to the intense repulsion between the O 2p lone pairs and the excessively bent O-Al-O angle. Additionally, the density of SiOAl2 type TO motif could serve as an indicator to determine the relationship between structure and fluidity. Our results challenge the traditional polymerization degree theory and suggest the need to reassess high-temperature liquid properties that govern processes in the Earth and industry by monitoring transient motifs.

Design and fabrication of a polydimethylsiloxane device for evaluating the effect of pillar geometry and configuration in the flow separation using deterministic lateral displacement.

The advancement of microfluidics and the manufacturing of microdevices has led to a strategic change in the biomedical industry. The flow through narrow channels and the pillars are placed strategically, leading to the phenomenon of particle separation through deterministic lateral displacement (DLD). In such a phenomenon, the shape, size, location and orientation of the obstacles play an important role. For the first time, particle separation is achieved with DLD modules having high row shift angles of 25°, 30° and 35°, reducing the number of pillars. The significance of circular and triangular micropillars executing deterministic lateral displacement, oriented at different angles, has been investigated, and it is found that the triangular pillars oriented at 75° resulted in better separation compared to the other configurations. In this report, the fabrication, location, orientation of the micropillars and the selection of appropriate process parameters are detailed. The structures are fabricated on silicon wafers using the standard photolithography process followed by the deep reactive ion etching process. These dies are further used to fabricate the polydimethylsiloxane-based microfluidic chips. These fabricated devices are characterised by their size, structure and quality using 3D microscopy and scanning electron microscopy. Further, blood plasma separation is carried out using the devices fabricated in this work, and the particles at the inlet and outlets are evaluated using microscopy and a novel image processing technique, replacing the use of a hemocytometer. The path traced by the particles at different flow conditions is numerically evaluated and validated with experiments. The novel device is capable of separating blood cells from plasma with a recovery factor varying from 44% to 100%. PDMS-PDMS bonding experiments using oxygen and argon plasma have been carried out to evaluate the maximum bond strength and flow velocity in the devices. It is observed that the oxygen plasma results in a bond strength of 0.404 N mm-1, thus a high throughput of 135.34 µL s-1 is achieved using the fabricated device.

Knowledge, attitude, and practice toward self-control of dental plaque among patients with periodontal diseases: a cross-sectional study.

BACKGROUND: The development of periodontal disease is closely linked to individual oral healthcare behaviors. This study aimed to investigate the knowledge, attitude, and practice (KAP) toward the self-control of dental plaque among patients with periodontal diseases. METHODS: This cross-sectional study was conducted at Jinan Stomatological Hospital between July 2022 and September 2022 through a self-administrated questionnaire for patients with periodontal diseases. RESULTS: A total of 563 participants were included. Among them, 147 (26.11%) had gingivitis and 416 (73.89%) had periodontitis. Participants' knowledge, attitude, and practice scores were 8.71 ± 2.81 (range 0-12), 39.82 ± 3.69 (range 10-50), 33.13 ± 5.91 (range 11-55), respectively. The multivariate logistic regression analysis showed that the knowledge [odds ratio (OR) = 1.212, 95% confidence interval (CI): 1.097-1.339, P < 0.001], attitude (OR = 1.132, 95% CI: 1.070-1.198, P < 0.001), occupation, especially in the commercial and service industry (OR = 0.488, 95% CI: 0.221-1.080, P = 0.007), and income of 10,000-20,000 yuan (OR = 0.476, 95% CI: 0.258-0.877, P = 0.017) were independently associated with good practice. CONCLUSIONS: Chinese patients with periodontal diseases demonstrated satisfactory knowledge and attitudes regarding oral hygiene, but the practical aspects need more promotion and training, especially in daily brushing frequency, usage of oral irrigator and interdental brush. Individualized approach should consider patients' knowledge, attitudes, occupation and income level.

Lyotropic Liquid Crystal (LLC)-Templated Nanofiltration Membranes by Precisely Administering LLC/Substrate Interfacial Structure.

Mesoporous materials based on lyotropic liquid crystal templates with precisely defined and flexible nanostructures offer an alluring solution to the age-old challenge of water scarcity. In contrast, polyamide (PA)-based thin-film composite (TFC) membranes have long been hailed as the state of the art in desalination. They grapple with a common trade-off between permeability and selectivity. However, the tides are turning as these novel materials, with pore sizes ranging from 0.2 to 5 nm, take center stage as highly coveted active layers in TFC membranes. With the ability to regulate water transport and influence the formation of the active layer, the middle porous substrate of TFC membranes becomes an essential player in unlocking their true potential. This review delves deep into the recent advancements in fabricating active layers using lyotropic liquid crystal templates on porous substrates. It meticulously analyzes the retention of the liquid crystal phase structure, explores the membrane fabrication processes, and evaluates the water filtration performance. Additionally, it presents an exhaustive comparison between the effects of substrates on both polyamide and lyotropic liquid crystal template top layer-based TFC membranes, covering crucial aspects such as surface pore structures, hydrophilicity, and heterogeneity. To push the boundaries even further, the review explores a diverse array of promising strategies for surface modification and interlayer introduction, all aimed at achieving an ideal substrate surface design. Moreover, it delves into the realm of cutting-edge techniques for detecting and unraveling the intricate interfacial structures between the lyotropic liquid crystal and the substrate. This review is a passport to unravel the enigmatic world of lyotropic liquid crystal-templated TFC membranes and their transformative role in global water challenges.

Boosting Plant Photosynthesis with Carbon Dots: A Critical Review of Performance and Prospects.

Artificially augmented photosynthesis in nano-bionic plants requires tunable nano-antenna structures with physiochemical and optoelectronic properties, as well as unique light conversion capabilities. The use of nanomaterials to promote light capture across photosystems, primarily by carbon dots, has shown promising results in enhancing photosynthesis through tunable uptake, translocation, and biocompatibility. Carbon dots possess the ability to perform both down and up-light conversions, making them effective light promoters for harnessing solar energy beyond visible light wavelengths.This review presents and discusses the recent progress in fabrication, chemistry, and morphology, as well as other properties such as photoluminescence and energy conversion efficiency of nano-antennas based on carbon dots. The performance of artificially boosted photosynthesis is discussed and then correlated with the conversion properties of carbon dots and how they are applied to plant models. The challenges related to the nanomaterial delivery and the performance evaluation practices in modified photosystems, consideration of the reliability of this approach, and the potential avenues for performance improvements through other types of nano-antennas based on alternative nanomaterials are also critically evaluated. It is anticipated that this review will stimulate more high-quality research in plant nano-bionics and provide avenues to enhance photosynthesis for future agricultural applications.

Dry-spun carbon nanotube ultrafiltration membranes tailored by anti-viral metal oxide coatings for human coronavirus 229E capture in water.

Although waterborne virus removal may be achieved using separation membrane technologies, such technologies remain largely inefficient at generating virus-free effluents due to the lack of anti-viral reactivity of conventional membrane materials required to deactivating viruses. Here, a stepwise approach towards simultaneous filtration and disinfection of Human Coronavirus 229E (HCoV-229E) in water effluents, is proposed by engineering dry-spun ultrafiltration carbon nanotube (CNT) membranes, coated with anti-viral SnO2 thin films via atomic layer deposition. The thickness and pore size of the engineered CNT membranes were fine-tuned by varying spinnable CNT sheets and their relative orientations on carbon nanofibre (CNF) porous supports to reach thicknesses less than 1 µm and pore size around 28 nm. The nanoscale SnO2 coatings were found to further reduce the pore size down to ∼21 nm and provide more functional groups on the membrane surface to capture the viruses via size exclusion and electrostatic attractions. The synthesized CNT and SnO2 coated CNT membranes were shown to attain a viral removal efficiency above 6.7 log10 against HCoV-229E virus with fast water permeance up to ∼4 × 103 and 3.5 × 103 L.m-2.h-1.bar-1, respectively. Such high performance was achieved by increasing the dry-spun CNT sheets up to 60 layers, orienting successive 30 CNT layers at 45°, and coating 40 nm SnO2 on the synthesized membranes. The current study provides an efficient scalable fabrication scheme to engineer flexible ultrafiltration CNT-based membranes for cost-effective filtration and inactivation of waterborne viruses to outperform the state-of-the-art ultrafiltration membranes.

The physical encapsulation and chemical fixation of Zn during thermal treatment process of municipal solid waste incineration (MSWI) fly ash.

Thermal treatment is a promising treatment technology of municipal solid waste incineration (MSWI) fly ash because of its detoxication and volume reduction. However, the relationship between immobilization of heavy metals and mineral transformation during thermal treatment remains unclear. In this study, the immobilization mechanism of Zn during thermal treatment process of MSWI fly ash was investigated by experiment and calculation. The results show that addition of SiO2 facilitates transition of dominant minerals from melilite to anorthite during sintering, increases liquid content during melting and improves liquid polymerization degree during vitrification. ZnCl2 tends to be physically encapsulated by liquid phase, and ZnO is mainly chemically fixed into minerals at high temperature. Increase in both liquid content and liquid polymerization degree favors the physical encapsulation of ZnCl2. The decreasing order of chemical fixation ability of minerals to ZnO is spinel > melilite > liquid > anorthite. To better immobilize Zn during sintering and vitrification process chemical composition of MSWI fly ash should be located in melilite and anorthite primary phases of pseudo-ternary phase diagram, respectively. The results are helpful to understand immobilization mechanism of heavy metals and avoid volatilization of heavy metals during thermal treatment process of MSWI fly ash.

Enhanced pollutant photodegradation over nanoporous titanium-vanadium oxides with improved interfacial interactions.

This study addressed the separation problem of colloidal catalytic powder from its solution and pore blockage of traditional metallic oxides by fabricating nanoporous composites of titanium (Ti)-vanadium (V) oxide via magnetron sputtering, electrochemical anodization, and annealing processes. The effect of V-deposited loading on the composite semiconductors was investigated by varying V sputtering power (20-250 W) to correlate their physicochemical properties to the photodegradation performance of methylene blue. The obtained semiconductors revealed circular and elliptical pores (14-23 nm) and formed different metallic and metallic oxide crystalline phases. Within the nanoporous composite layer, V ions substituted Ti4+, leading to Ti3+ formation accompanied by decreased band gap values and higher visible-light absorption. Thus, the band gap of TiO2 was 3.15 eV, while that of Ti-V oxide with the maximum V content (at 250 W) was 2.47 eV. The interfacial separators between clusters in the mentioned composite created traps disrupting the charge carrier movements between crystallites, thereby decreasing the photoactivity. In contrast, the composite prepared with the minimum V content showed approximately 90% degradation efficiency under solar-simulated irradiation resulting from the homogeneous V dispersion and the lower recombination possibility, owing to its p-n heterojunction constituent. The nanoporous photocatalyst layers with their novel synthesis approach and outstanding performance can be applied in other environmental remediation applications.

Nanobionics-Driven Synthesis of Molybdenum Oxide Nanosheets with Tunable Plasmonic Resonances in Visible Light Regions.

Nanobionics-driven synthesis offers a process of designing and synthesizing functional materials on a nanoscale based on the structures and functions of biological systems. An approach such as this is environmentally friendly and sustainable, providing a viable option for synthesizing functional nanomaterials for catalysis and nanoelectronic components. In this work, we present a facile and green nanobionics approach to synthesize plasmonic HxMoO3 by interacting chloroplasts extracted from spinach with two-dimensional (2D) MoO3 nanoflakes. The generated plasmon resonances can be modulated in the visible wavelength ranges, and the efficiency to form the plasmonic materials is enhanced by 90% within 45 min of light excitation compared to reactions without chloroplast involvement. Such a characteristic is ascribed to the interfacial carrier dynamics between the two entities in the reactions, in which highly doped metal oxides with quasi-metallic properties can be formed to generate optical absorptions in the visible light region. The green synthesized plasmonic materials show high photocatalytic activities without the coupling of semiconductors, providing a promising nanoelectronics unit, based on the nanobionics-driven synthesized plasmonic materials.

Inhibition of Autophagy Promotes the Elimination of Liver Cancer Stem Cells by CD133 Aptamer-Targeted Delivery of Doxorubicin.

Doxorubicin is the most frequently used chemotherapeutic agent for the treatment of hepatocellular carcinoma. However, one major obstacle to the effective management of liver cancer is the drug resistance derived from the cancer stem cells. Herein, we employed a CD133 aptamer for targeted delivery of doxorubicin into liver cancer stem cells to overcome chemoresistance. Furthermore, we explored the efficacy of autophagy inhibition to sensitize liver cancer stem cells to the treatment of CD133 aptamer-doxorubicin conjugates based on the previous observation that doxorubicin contributes to the survival of liver cancer stem cells by activating autophagy. The kinetics and thermodynamics of aptamer-doxorubicin binding, autophagy induction, cell apoptosis, and self-renewal of liver cancer stem cells were studied using isothermal titration calorimetry, Western blot analysis, annexin V assay, and tumorsphere formation assay. The aptamer-cell binding andintracellular accumulation of doxorubicin were quantified via flow cytometry. CD133 aptamer-guided delivery of doxorubicin resulted in a higher doxorubicin concentration in the liver cancer stem cells. The combinatorial treatment strategy of CD133 aptamer-doxorubicin conjugates and an autophagy inhibitor led to an over 10-fold higher elimination of liver cancer stem cells than that of free doxorubicin in vitro. Future exploration of cancer stem cell-targeted delivery of doxorubicin in conjunction with autophagy inhibition in vivo may well lead to improved outcomes in the treatment of hepatocellular carcinoma.

Oxidized Chitosan-Tobramycin (OCS-TOB) Submicro-Fibers for Biomedical Applications.

Chitosan (CS) is a biodegradable, biocompatible, and non-toxic natural amino-poly-saccharide with antibacterial ability, owing to its positively charged amino groups. However, the low charge density leads to poor antibacterial efficiency which cannot meet the biomedical application requirements. In this study, Tobramycin (TOB) was grafted onto the backbone of oxidized chitosan (OCS) to synthesize oxidized chitosan-tobramycin (OCS-TOB). FTIR, 1H NMR and elemental analysis results demonstrated that OCS-TOB was successfully synthesized. OCS-TOB/PEO composite fibrous materials were produced by a self-made centrifugal spinning machine. In vitro experiments showed that cells proliferated on the submicro-fibrous OCS-TOB/PEO of appropriate concentration, and the antibacterial ability of OCS-TOB was much improved, compared with pristine CS. The results demonstrated that OCS-TOB/PEO nanofibrous materials could potentially be used for biomedical applications.

Atomically-thin Schottky-like photo-electrocatalytic cross-flow membrane reactors for ultrafast remediation of persistent organic pollutants.

The remediation of persistent organic pollutants in surface and ground water represents a major environmental challenge worldwide. Conventional physico-chemical techniques do not efficiently remove such persistent organic pollutants and new remediation techniques are therefore required. Photo-electro catalytic membranes represent an emerging solution that can combine photocatalytic and electrocatalytic degradation of contaminants along with molecular sieving. Herein, macro-porous photo-electro catalytic membranes were prepared using conductive and porous stainless steel metal membranes decorated with nano coatings of semiconductor photocatalytic metal oxides (TiO2 and ZnO) via atomic layer deposition, producing highly conformal and stable coatings. The metal - semiconductor junction between the stainless steel membranes and photocatalysts provides Schottky - like characteristics to the coated membranes. The PEC membranes showed induced hydrophilicity from the nano-coatings and enhanced electro-chemical properties due to the Schottky junction. A high electron transfer rate was also induced in the coated membranes as the photocurrent efficiency increased by 4 times. The photo-electrocatalytic efficiency of the TiO2 and ZnO coated membranes were demonstrated in batch and cross flow filtration reactors for the degradation of persistent organic pollutant solution, offering increased degradation kinetic factors by 2.9 and 2.3 compared to photocatalysis and electrocatalysis, respectively. The recombination of photo-induced electron and hole pairs is mitigated during the photo-electrocatalytic process, resulting in an enhanced catalytic performance. The strategy offers outstanding perspectives to design stimuli-responsive membrane materials able to sieve and degrade simultaneously toxic contaminants towards greater process integration and self-cleaning operations.

Temperature-Responsive Aldehyde Hydrogels with Injectable, Self-Healing, and Tunable Mechanical Properties.

Injectable and self-healing hydrogels with exemplary biocompatibility and tunable mechanical properties are urgently needed due to their significant advantages for tissue engineering applications. Here, we report a new temperature-responsive aldehyde hydrogel with dual physical-cross-linked networks and injectable and self-healing properties prepared from an ABA-type triblock copolymer, poly{[FPMA(4-formylphenyl methacrylate)-co-DEGMA[di(ethylene glycol) methyl ether methacrylate]-b-MPC(2-methacryloyloxyethyl phosphorylcholine)-b-(FPMA-co-DEGMA)}. The thermoresponsive poly(DEGMA) segments drive the dehydration and hydrophobic interaction, enabling polymer chain winding as the first cross-linking network, when the temperature is raised above the critical gelation temperature. Meanwhile, the benzaldehyde groups offer physical interactions, including hydrogen bonding and hydrophobic and π-π stacking interactions as the second cross-linking network. When increasing the benzaldehyde content in the triblock copolymers from 0 to 8.2 mol %, the critical gelation temperature of the resulted hydrogels dropped from 35.5 to 19.9 °C and the mechanical modulus increased from 21 to 1411 Pa. Owing to the physical-cross-linked networks, the hydrogel demonstrated excellent injectability and self-healing properties. The cell viabilities tested from MTT assays toward both normal lung fibroblast cells (MRC-5) and cancerous cervical (HeLa) cells were found to be 100 and 101%, respectively, for varying polymer concentrations up to 1 mg/mL. The 3D cell encapsulation of the hydrogels was evaluated by a cytotoxicity Live/Dead assay, showing 92% cell viability. With these attractive physiochemical and biological properties, this temperature-responsive aldehyde hydrogel can be a promising candidate as a cell scaffold for tissue engineering.

Isolating motile sperm cell sorting using biocompatible electrospun membranes.

Motility is an indicator of sperm cell viability due to higher probability in swimming through the female reproductive tract and undergo fertilization with the egg cell. Centrifugation method is a technique to process high volume semen and isolate motile sperm cells but decreases the biochemical integrity of spermatozoa due to the contact with reactive oxygen species (ROS) from dead cells released during centrifugation. This study uses solution electrospun poly(ε-caprolactone) membranes as an alternative in isolating motile spermatozoa by utilizing a rationally designed 3D printed module set up, providing the same benefits as commercially available techniques with minimal processing time, and bypassing the centrifugation step to provide higher quality sperm cells. The membranes, with nominal pore size distributions ranging from 5 to 6 µm are highly porous structures suitable for establishing baseline data for sperm cell sorting by motility. The proposed method allows for isolation of motile sperm cells with 74% purity, while decreasing the processing time by 98% when compared to centrifugation techniques. This novel approach provides a facile method for isolating motile spermatozoa directly from frozen semen samples without any pretreatments and is easily scalable for small and medium scale farms as well as larger industries.

Edible films and coatings for shelf life extension of mango: a review.

Edible films and coatings are eco-friendly promising materials for preserving the quality and extending the shelf life of fresh and minimally-processed fruits. They can form protective layers around fruits, regulate their respiration rates, and protect them from loss of water, tissue softening, browning, and microbial contamination. Edible films and coatings have many advantages over other post-harvest treatments. They can add commercial value to fruits by enhancing their appearance, and act as carriers of functional ingredients, such as antioxidants, antimicrobial agents and nutraceuticals. Mango, a highly perishable tropical fruit, has a short post-harvest life, which limits transport to distant markets. Application of edible films and coatings on mango fruits is an effective method to preserve their quality and safety. This paper provides an overview of desirable properties for films and coatings, and recent development in different edible coatings for both fresh and minimally-processed mango. The most popular edible coating materials, such as chitosan, waxes, starch, gums, and cellulose used for mango are reviewed. The commercialization of coating formulations and equipment used for application of coatings are discussed. The environmental impacts, safety aspects, and the challenges encountered are outlined. The opportunities to use other coating materials, such as aloe-vera gel, microbial polysaccharides, and photosynthetic microorganisms are also examined.

Controlling phase and rheological behaviours of hexagonal lyotropic liquid crystalline templates for nanostructural administration and retention.

Introducing polymerizable monomers into a binary hexagonal lyotropic liquid crystalline (LLC) template is a straightforward way for retaining the nanostructure but will decrease attractive intra- and inter- aggregate interactions. It is therefore crucial to understand the interfacial interactions at nanoscale after introducing the monomers but prior to polymerization. Herein, active species, poly (ethylene glycol) diacrylate (PEGDA) and 2-hydroxyethyl methacrylate (HEMA), were introduced into hexagonal LLC of dodecyl trimethylammonium bromide and water to explore the structural variables, dimensional stability, and dynamic property. At a proper volume ratio of PEGDA/HEMA (1/4), the system presents excellent homogeneity with a higher dimensional stability and lower dynamic property from rheological assessments, thereby achieving robust, free-standing, and transparent membranes after photo-polymerization. The unique property of the system also lies in the much lower order-disorder transition temperature (45 °C) that facilitates the reorientation of mesochannels. They are in contrast inaccessible for the ternary system only with PEGDA, though the nanostructure for both systems could be retained. An insight into subtle variations in these parameters allows us to prepare a polymerizable template possessing higher dimensional stability and suitable flexibility via molecular design, thereby enabling simultaneous structural alignment and retention for the development of functional nanomaterials.

Zwitterionic Block Copolymer Prodrug Micelles for pH Responsive Drug Delivery and Hypoxia-Specific Chemotherapy.

Tirapazamine (TPZ) and its derivatives (TPZD) have shown their great potential for efficiently killing hypoxic cancer cells. However, unsatisfactory clinical outcomes resulting from the low bioavailability of the low-molecular TPZ and TPZD limited their further applications. Precise delivery and release of these prodrugs via functional nanocarriers can significantly improve the therapeutic effects due to the targeted drug delivery and enhanced permeability and retention (EPR) effect. Herein, zwitterionic block copolymer (BCP) micelles with aldehyde functional groups are prepared from the self-assembly of poly(2-methacryloyloxyethyl phosphorylcholine-b-poly(di(ethylene glycol) methyl ether methacrylate-co-4-formylphenyl methacrylate) [PMPC-b-P(DEGMA-co-FPMA)]. TPZD is then grafted onto PMPC-b-P(DEGMA-co-FPMA) to obtain a polymer-drug conjugate, PMPC-b-P(DEGMA-co-FPMA-g-TPZD) (BCP-TPZ), through the formation of a pH-responsive imine bond, exhibiting a pH-dependent drug release profile owing to the cleavage of the imine bond under acidic conditions. Outstandingly, BCP-TPZ shows around 13.7-fold higher cytotoxicity to hypoxic cancer cells in comparison to normoxic cancer cells evaluated through an in vitro cytotoxicity assay. The pH-responsiveness and hypoxia-specific cytotoxicity confer BCP-TPZ micelles a great potential to achieve precise delivery of TPZD and thus enhance the therapeutic effect toward tumor-hypoxia.

Synthesis of porous iron hydroxy phosphate from phosphate residue and its application as a Fenton-like catalyst for dye degradation.

Phosphate residue is a kind of hazardous solid waste and if not properly disposed of, could cause serious environmental contaminations. The abundant iron salt available in phosphate residue can be used to prepare photo-Fenton catalytic reagent for wastewater treatment. In this study, the phosphate residue was effectively purified by a hydrothermal recrystallization method, reaching an iron phosphate purity of 94.2%. The particles of iron phosphate were further processed with ball milling with their average size reduced from 19.4 to 1.6 µm. By hydrothermal crystallization of iron phosphate and thermal decomposition of oxalate precursor, porous iron hydroxy phosphate was prepared. The modified porous iron hydroxy phosphate (m-PIHP) of higher surface area with iron oxalate on its surface can degrade 98.87% of Rhodamine B in 15 min. Cyclic experiment showed that the catalyst still had a good catalytic activity after six cycles (>40%). The X-ray photoelectron spectroscopy results showed that the iron oxalate complex on the catalyst surface decomposed to produce ferrous ions and accelerated the rate of •OH production. The current work demonstrated that the m-PIHP synthesized from phosphate residue and modified with iron oxalate can be used as an effective dye wastewater treatment agent.

Towards a High-Flux Separation Layer from Hexagonal Lyotropic Liquid Crystals for Thin-Film Composite Membranes.

Hexagonal lyotropic liquid crystals (HLLC) with uniform pore size in the range of 1~5 nm are highly sought after as promising active separation layers of thin-film composite (TFC) membranes, which have been confirmed to be efficient for water purification. The potential interaction between an amphiphile-based HLLC layer and the substrate surface, however, has not been fully explored. In this research, hydrophilic and hydrophobic microporous polyvinylidene fluoride (PVDF) substrates were chosen, respectively, to prepare TFC membranes with the active layers templated from HLLC, consisting of dodecyl trimethylammonium bromide, water, and a mixture of poly (ethylene glycol) diacrylate and 2-hydroxyethyl methacrylate. The pore size of the active layer was found to decrease by about 1.6 Å compared to that of the free-standing HLLC after polymerization, but no significant difference was observable by using either hydrophilic or hydrophobic substrates (26.9 Å vs. 27.1 Å). The water flux of the TFC membrane with the hydrophobic substrate, however, was higher than that with the hydrophilic one. A further investigation confirmed that the increase in water flux originated from a much higher porosity was due to the synergistic effect of the hydrophilic HLLC nanoporous material and the hydrophobic substrate.

Chironomidae (Midge) Sensitivities to Ammonia Using Multiple Endpoints in China and Australia for the Development of Water Quality Criteria for Freshwater River Systems in China.

Deriving water quality criteria (WQC) for aquatic risk assessment requires sufficient toxicity data, which can determine the accuracy of WQC. Given that toxicity data vary between test species and endpoints, there is a great need to compare such data to generate the most suitable data set for WQC derivation. In the present study, a series of 11 ammonia exposure bioassays were conducted on Chironomidae species in either China or Australia, with test species and test endpoints varied (2 Chironomus sp., enzymatic up to lethal endpoints, and no-observed-effect concentration up to median lethal concentration [LC50] as endpoint metrics). There were no statistically significant differences between toxicity results generated from China compared to Australia using Chironomus sp., indicating that published data on native species generated in different countries could be appropriate for inclusion in the development of local Chinese WQC. In addition, the Chironomidae larvae laboratory-based toxicity value (LC50 = 384.6 mg/L) was lower than that of the in situ field-based toxicity value (LC50 ≥ 451.2 mg/L) where sensitive life stages are used, and, specifically for C. riparius, endpoints linked to biochemical and gene expression effects could be as sensitive as or more sensitive than chronic endpoints, both of which were more sensitive than acute endpoints. These findings help in the development of WQC by demonstrating the suitability of inclusion of toxicity data from a range of sources, as well as adding to the overall pool of knowledge regarding sensitivity to ammonia which can be used in aquatic risk assessment. Environ Toxicol Chem  2021;40:2899-2911. © 2021 SETAC.