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Pb2+ is a heavy metal ion pollutant that poses a serious threat to human health and ecosystems. The conventional methods for detecting Pb2+ have several limitations. In this study, we introduce a novel fluorescent probe that enables the detection of Pb2+ in the near-infrared region, free from interference from other common ions. A unique characteristic of this probe is its ability to rapidly and accurately identify Pb2+ through ratiometric measurements accompanied by a large Stokes shift of 201 nm. The limit of detection achieved by probe was remarkably low, surpassing the standards set by the World Health Organization, and outperforming previously reported probes. To the best of our knowledge, this is the first organic small-molecule fluorescent probe with both near-infrared emission and ratiometric properties for the detection of Pb2+. We present a triple-mode sensing platform constructed using a probe that allows for the sensitive and selective recognition of Pb2+ in common food items. Furthermore, we successfully conducted high-quality fluorescence imaging of Pb2+ in various samples from common edible plants, HeLa cells, Caenorhabditis elegans , and mice. Importantly, the probe-Pb2+ complex exhibited tumour-targeting capabilities. Overall, this study presents a novel approach for the development of fluorescent probes for Pb2+ detection. [Display omitted] • This study develops a novel probe for ratiometric and NIR detection of Pb2+ for the first time. • A fluorescence/colorimetric/smartphone sensing platform for Pb2+ detection was fabricated. • The triple-mode sensing platform was successfully applied to the analysis of Pb2+ in various foods. • The probe was successfully applied to bioimaging and has tumour-targeting capabilities. [ABSTRACT FROM AUTHOR]

In practice, efficient, rapid and simple removal of Hg(II) from water using nano adsorbents remains an extreme challenge at present. In this work, a novel Hg(II) adsorbent based on functionalized graphdiyne oxide (GDYO-3M) membrane was designed for the purpose of effective and prompt removal of Hg(II) from environmental water for the first time. Through filtration, the proposed GDYO-3M membrane (4 cm diameter size) fulfilled an exceeding 97% removal efficiency in > 10 L water containing 0.1 mg/L Hg(II) within 1 h. Due to the presence of -SH groups, the GDYO-3M membrane demonstrates an excellent selectivity for Hg(II) vs. 14 co-existing metal ions. In the meantime, the GDYO-3M membrane represents a favorable reproducibility (above 95% Hg(II) removal) after 9 successive adsorption-desorption cycles. For the mechanism, it is believed that the active sites in the adsorption process mainly include -SH groups, oxygen-containing functional groups, and alkyne bonds. Further, the GDYO-3M membrane can be utilized as an enrichment approach for sensitive analysis of Hg(II) in water based on energy dispersion X-ray fluorescence spectrometry (ED-XRF), whose detection limit (LOD) reaches 0.2 μg/L within 15 min. This work not only provides a green and efficient method for removing Hg(II), but also renders an approach for rapid, sensitive and portable Hg(II) detection in water. [Display omitted] • A novel Hg(II) absorbent was developed based on functionalized graphdiyne oxide for the first time. • GDYO‐3M membrane exhibits exceptional selectivity and reproducibility for Hg(II) removal from water. • GDYO‐3M membrane facilitates the fast detection of Hg(II) by portable ED-XRF with an excellent sensitivity. [ABSTRACT FROM AUTHOR]

The adsorption behavior and interaction mechanisms of extracellular polymeric substances (EPS) of Pseudomonas aeruginosa OMCS-1 towards chromium (Cr), lead (Pb), and cadmium (Cd) were investigated. EPS-covered (EPS-C) cells exhibited significantly higher (p < 0.0001; two-way ANOVA) removal of Cr (85.58 ± 0.39%), Pb (81.98 ± 1.02%), and Cd (73.88 ± 1%) than EPS-removed (EPS-R) cells. Interactions between EPS-heavy metals were spontaneous (ΔG<0). EPS-Cr(VI) and EPS-Pb(II) binding were exothermic (ΔH<0), while EPS-Cd(II) binding was endothermic (ΔH>0) process. EPS bonded to Pb(II) via inner-sphere complexation by displacement of surrounding water molecules, while EPS-Cr(VI) and EPS-Cd(II) binding occurred through outer-sphere complexation via electrostatic interactions. Increased zeta potential of Cr (29.75%), Pb (41.46%), and Cd (46.83%) treated EPS and unchanged crystallinity (CI XRD =0.13), inferred EPS-metal binding via both electrostatic interactions and complexation mechanism. EPS-metal interaction was predominantly promoted through hydroxyl, amide, carboxyl, and phosphate groups. Metal adsorption deviated EPS protein secondary structures. Strong static quenching mechanism between tryptophan protein-like substances in EPS and heavy metals was evidenced. EPS sequestered heavy metals via complexation with C-O, C-OH, C O/O-C-O, and NH/NH 2 groups and ion exchange with –COOH group. This study unveils the fate of Cr, Pb, and Cd on EPS surface and provides insight into the interactions among EPS and metal ions for metal sequestration. [Display omitted] • The presence of EPS on bacterial surface facilitates the adsorption of metal ions. • EPS-metal binding was spontaneous, exothermic for Cr and Pb, and endothermic for Cd. • Electrostatic interaction and complexation mechanism of EPS and metal binding. • Heavy metal adsorption deviated the secondary structures of EPS proteins. • Static quenching mechanism between tryptophan containing proteins and heavy metals. [ABSTRACT FROM AUTHOR]

Film covers have been widely applied worldwide. However, the effects of long-term plastic film mulching use on heavy metal (HM) activity in soil remain unclear. This study focused on farmland in the upstream part of the Pearl River in China and collected 103 soil samples after 2, 5, and 15 years of plastic film mulching. The main environmental factors controlling microplastics (MPs), plasticizer phthalic acid esters (PAEs), HM pollution characteristics, and HM activity were analyzed. The results showed that Polyethylene (PE) and di(2-ethylhexyl) dicyclohexyl phthalate (DCHP) were the main MPs and PAEs, respectively. The abundance of MPs and the concentrations of free HM ions (Cd, Cu, and Ni) in the soil solution increased with increasing plastic film mulching duration. The Partial Least Squares Path Model (PLS-PM) indicated that after plastic film mulching, soil chemical properties (pH/amorphous Fe) and biological properties (Dissolved organic carbon/ Easily oxidizable carbon/Microbial biomass carbon) were the main controlling factors for free and complexed HM ions (Cd, Pb, Cu, and Ni). These results suggest that, after plastic film mulching, MPs indirectly regulate HM activity by altering soil properties. This study provides a new perspective for the management of MPs and HM activities in agricultural ecosystems. [Display omitted] • MPs abundance and HM activity in soil increased with mulch duration. • PE is one of the main types of MPs in the soils of the upstream Pearl River. • pH/Fe-Tamm/DON greatly impacts free HM ions after mulching. • DOC/EOC/MBC are very sensitive to complexed HM ions after mulching. [ABSTRACT FROM AUTHOR]

Microalgal biomasses have been established as promising biosorbents for biosorption to remove heavy metal ions (HMIs) from wastewaters and contaminated natural waterbodies. Understanding the mechanism is important for the development of cost-effective processes for large scale applications. In this paper, a simple mathematical model was proposed for the predication of biosorption capacity of HMI by microalgal cells based on single cell mass, cell size, and HMI radius. One fundamental assumption based on which this model was developed, i.e., the biosorption of HMI by microalgal cells is predominantly monolayer bio-adsorption, was established based on kinetic, isothermal, FTIR, and Pb(II) distribution data generated in this study and in literature. The model was validated using a combination of experimental and literature data as well, demonstrating its capability to provide reasonable estimations although with discrepancies. The biosorption capacities of HMIs (mmol/g) by Chlorella vulgaris were experimentally determined to be in the following order: Pb(II)(0.360)> Zn(II)(0.325)> Cu(II)(0.254)> Ni(II)(0.249)> Cd(II)(0.235)> Co(II)(0.182). We systematically investigated the deviations of the predicted biosorption capacities in term of the effects of a few important parameters that were unaccounted for in the model, including the nanostructures on cell surface, HMI electronegativity, and biosorption buffer pH. Results suggest that the nanostructures on cell wall, likely the hairlike fibers, might be the primary locations where the binding sites for HMI were housed. Furthermore, isothermal data, which is suported by the predictions of this model, indicate the each effective binding site on C. vulgaris cell surface could bind to more than one Co(II) in biosorption while each of the other five HMIs tested in this study required more than one binding sites. [Display omitted] • Multifaceted evidence shows monolayer bio-adsorption predominant in HMI biosorption. • Model developed based on cell size, ionic radius, and monolayer bio-adsorption. • Model deviations highlight importance on cell surface housing binding sites. • HMI properties, e.g., electronegativity, have tremendous effects of biosorption. [ABSTRACT FROM AUTHOR]

Membrane technologies are effective for treating leachate, but they generate leachate concentrates (LCs), which contain elevated humic acids (HAs) and metals. LCs are very challenging and expensive to treat; but in-situ coagulation-electrochemical oxidation (CO-EO) treatment is promising. We previously hypothesized and proved that substituting the widely used graphite cathode with an Al cathode will generate Al(OH) 3 floccules that would enhance HAs removal in CO-EO systems. However, the fundamental mechanisms are unclear. Here, we examined this hypothesis using laboratory experiments (using an Al cathode and a Ti/Ti 4 O 7 anode CO-EO system) and performed molecular dynamics (MD) simulation to investigate the underlying mechanisms. Up to 84.2% HAs was removed by the Al-cathode system, which is ∼10% higher than a graphite cathode-based system. Based on MD simulation we found that enhanced HAs removal occurred via two steps: (1) degradation by oxidants produced at the anode, and (2) subsequent coagulation with the Al(OH) 3 generated from the Al cathode. This finding challenges the current belief that whole HAs and Al(OH) 3 directly flocculate. Meanwhile, metal removal efficiency by the graphite cathode system was only 0.8–13.9%, which increased up to 13-folds at most when in the Al cathode system. This work provides new molecular-level insights into an efficient electrochemical treatment of LC. [Display omitted] • Molecular scale understanding of coagulation-electrochemical oxidation was achieved. • Humic acids were degraded by oxidation before coagulation with Al(OH) 3 floccules. • Al cathode increased metal removal by a maximum of 13-fold compared to graphite. • Metals' removal was aided by coagulation with humic acid fragments and Al(OH) 3. [ABSTRACT FROM AUTHOR]

Biochar adsorbents synthesized from food and agricultural wastes are commonly applied to eliminate heavy metal (HM) ions from wastewater. However, biochar's diverse characteristics and varied experimental conditions make the accurate estimation of their adsorption capacity (q e) challenging. Herein, various machine-learning (ML) and three deep learning (DL) models were built using 1518 data points to predict the q e of HM on various biochars. The recursive feature elimination technique with 28 inputs suggested that 14 inputs were significant for model building. FT-transformer with the highest test R2 (0.98) and lowest root mean square error (RMSE) (0.296) and mean absolute error (MAE) (0.145) outperformed various ML and DL models. The SHAP feature importance analysis of the FT-transformer model predicted that the adsorption conditions (72.12%) were more important than the pyrolysis conditions (25.73%), elemental composition (1.39%), and biochar's physical properties (0.73%). The two-feature SHAP analysis proposed the optimized process conditions including adsorbent loading of 0.25 g, initial concentration of 12 mg/L, and solution pH of 9 using phosphoric-acid pre-treated biochar synthesized from banana-peel with a higher O/C ratio. The t-SNE technique was applied to transform the 14-input matrix of the FT-Transformer into two-dimensional data. Finally, we outlined the study's environmental implications. [Display omitted] • 28 inputs containing 1518 data points covering 7 HMs onto 16 biochars. • Adsorption capacity was predicted by three ML models of deep learning architectures. • The FT-Transformer model showed the best prediction with acceptable computation. • The adsorption experimental condition with 79% was the most vital input class. • Dimension reduction was performed using t-SNE. [ABSTRACT FROM AUTHOR]

Understanding the facet-dependent adsorption behavior and mechanism of heavy metal ions (HMs) on two-dimensional (2D) Janus nanoclays has important implications for the environment and ecosystem but still remains elusive. Herein, ultrathin Janus serpentene (2D serpentine) nanosheets were fabricated via a facile, nontoxic, and residue-free exfoliation strategy. Fabricated serpentene nanosheets exhibited promising Cd(II) and Pb(II) adsorption capacities due to their high surface areas and abundant active sites, approximately four times higher than those of bulk serpentine powders. Interestingly, Cd(II) and Pb(II) adsorption on serpentene nanosheets exhibited a facet-dependent feature, with the adsorption amount on the Mg–OH plane considerably higher than that on the Si–O plane. This facet-dependent adsorption behavior was mainly attributed to the difference in the interaction mechanisms of HMs with the Mg–OH (monodentate inner-sphere complexation) and Si–O (outer-sphere complexation) planes, which was further confirmed via density functional theory calculations. The Cd(II) adsorption on serpentene nanosheets was limited by strong kinetic restrictions (e.g., stronger electrostatic repulsion and higher dehydration energy barrier than that for Pb(II) adsorption). This study provides insights into the facet-dependent adsorption mechanisms of HMs on Janus serpentene nanosheets, which can be extended to other nanoclays used in wastewater treatment and many environmental processes. [Display omitted] • Ultrathin Janus serpentene nanosheets were fabricated via liquid-phase exfoliation. • The facet-dependent adsorption of HMs on serpentene nanosheets was deciphered by QCM-D and DFT. • Adsorption of HMs on Mg–OH plane was significantly higher than that on Si–O plane. • Monodentate complexation of Cd/Pb(II) on Mg–OH plane was the main adsorption mode. • Adsorption of Cd(II) on Mg–OH plane was kinetically restricted compared to Pb(II). [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have become a promising candidate for the remediation of heavy metal pollution. However, researches on COF adsorbents still have challenges on maintaining good optical properties and adsorption performance under harsh conditions. Herein, a fully π-conjugated COF with dual binding sites (Bpy- sp 2 c -COF) is reported for rapid fluorescence recognition and enhanced adsorption towards divalent heavy metal ions. The vinylene-linkage lattice shows strong luminescence and excellent stability in both strong acidity and basicity. Bpy- sp 2 c -COF demonstrates not only nanomolar-scale detection of divalent heavy metal ions, but also good adsorption capacity (Hg2+ 718.48, Ni2+ 278.64, Cu2+ 260.11, and Co2+ 126.23 mg/g). Experimental and theoretical studies reveal the intramolecular charge transfer as the fluorescence quenching mechanism. Further simulation results demonstrate the cyano and bipyridine groups on the lattice can act as dual binding sites for divalent heavy metal ions. Experimental results confirmed the adsorption capacity of Bpy- sp 2 c -COF superior to that of COFs with either cyano groups (Hg2+ 415.34, Ni2+ 165.60, Cu2+ 160.55, and Co2+ 73.14 mg/g), or bipyridine groups (Hg2+ 369.25, Ni2+ 133.41, Cu2+ 133.32, and Co2+ 69.23 mg/g). Besides, robust regeneration of the adsorbent could be achieved over 10 cycles. The fully π-conjugated COF with dual binding sites provides a new approach for designing next-generation sensors and adsorbents with excellent performances. [Display omitted] • A fully π-conjugated COF with excellent stability and strong emission is reported. • Efficient detection and robust adsorption of divalent heavy metal ions are achieved. • The co-action of bipyridine and cyano groups achieves superior adsorption capacity. • Such lattice opens a new approach for designing advanced adsorbents and sensors. [ABSTRACT FROM AUTHOR]

• Frequency increment caused significant decrement in effective permittivity. • Effective conductivity-porosity equation considering particle conductivity developed. • 3D Cole-Cole plot shows Cole-Cole circle expansion at higher water content. • Resonance strength of polymer or metal modified clays increases with water content. • Polymer or metal ions has little influence on resonance time and stretching exponent. Owing to its high surface area and high surface charge density, clay, either contaminated with heavy metal ions or modified with organic additives as barrier materials, is difficult to assess and monitor. Complex dielectric permittivity (κ*) showed promising potential in tackling the above issues. In this study, the complex dielectric permittivity (κ*) of clays modified with a surfactant, four polymers, and four metal ions was measured at frequencies from 0.2–20 GHz. With the addition of polymer and metal ions, increasing frequency caused a slight decrement in real permittivity but a significant decrement in effective permittivity. A modified linearity polynomial equation, which considered the particle conductivity, was developed to fit the relationship between effective conductivity (σeff) and porosity ranging from 0.7 to 1.0. A three-dimensional Cole-Cole plot (κ ′- κeff″ - w) shows Cole-Cole circle expansion at higher water content. The resonance strength of modified clays was observed to increase with water content, which suggests that the number of water molecules in the diffuse layer of polymer or metal ions saturated clay increased. However, sorbed polymer and metal ions have an insignificant influence on the resonance time τ s and stretching exponent 1-α. κ* can provide nondestructive characterization of metal or polymer modified clays. [ABSTRACT FROM AUTHOR]

• An aeration pretreatment enlarged root aerenchyma and improved apical oxygen secretion of Triarrhena sacchariflora seedlings. • The aeration pretreatment enhanced the tolerance and absorption of T. sacchariflora seedlings to cadmium and copper. • The aeration pretreatment shows a great potential in efficient phytoremediation of heavy metal-polluted wetlands. Two solution cultures with different oxygen pretreatments were used to investigate (ⅰ) the variation in the radial oxygen loss in the roots and root morphology of Triarrhena sacchariflora seedlings and (ii) their tolerance to Cu2+ and Cd2+, as well as both the metal uptake and accumulation by pretreated seedlings. Developed aerenchyma in the roots was induced by the hypoxia pretreatment (HP) and aeration pretreatment (AP), for which root porosity, respectively, increased by 45.76%–53.39% and 84.07%–88.66%. AP altered the natural radial oxygen loss coupled to an enhanced secretion of oxygen in the root tips. AP was found to effectively improve the seedlings' tolerance to Cu2+ and Cd2+, facilitating their growth, thereby increasing their root diameter, dry weight, and number of root tips, as well as promoting shoot growth. AP was capable of promoting the uptake and bioaccumulation in seedlings of Cu2+ and Cd2+; it also induced more Cu2+ and Cd2+ immobilized in roots so that less of either metal was transported from roots to shoots, which may well be a key mechanism for strengthening seedlings' tolerance to metal ions. Our experimental results suggest that AP offers great potential for the remediation of heavy metal-contaminated wetlands. [ABSTRACT FROM AUTHOR]

• The flower globular magnesium hydroxide (FGMH) was synthesized for the first time. • The method using trisodium citrate as crystal modifier is mild and easy to operate. • The prepared materials exhibited good dispersion and high specific surface area. • FGMH particles with rough surface solve the problem of difficult filtration. • The max-adsorption capacity of the materials uptake Ni(II) ions was 287.11 mg/g. To remove toxic Ni(II) ions from wastewater, a novel flower globular magnesium hydroxide (FGMH) was prepared by a gentle method using trisodium citrate as a crystal modifier. This material exhibited a high specific surface area. The synthesized products and adsorption mechanism for Ni(II) ions were examined by diverse characterization technologies and methods. FGMH was employed to remove Ni(II) ions by the adsorption method. The effects of various parameters, viz., the amount of adsorbent, contact time, temperature and pH, on the removal rate by the adsorbent were investigated in detail. The kinetic data fitted well with a pseudo-second-order model and experimental equilibrium adsorption data conformed to a Langmuir isotherm under optimized conditions. The optimal process parameters included 30 mg of FGMH, a 50 min contact time, pH values between 6.07 and 7.71 for the Ni(II) solution, and adsorption at room temperature for 50 mL of 80 mg/L Ni(II) solution. The percentage of removal efficiency was found to be above 92.64%, and the maximum adsorption capacity of MH was 287.11 mg/g under optimum adsorption conditions. The analyses indicated that the Ni(II) ions were chemisorbed on the FGMH surface. [ABSTRACT FROM AUTHOR]

The detection of heavy metal ions Co2+ is of great significance to the environment and human health. Herein, a simple, highly selective and sensitive photoelectrochemical detection strategy for Co2+ was developed based on the enhanced activity by nanoprecipitated CoPi on the Au nanoparticle decorated BiVO 4 electrode. The new photoelectrochemical sensor has a low detection limit of 0.03 μΜ and wide detection range of 0.1–10, and 10–6000 μΜ, with a high selectivity over other metal ions. The Co2+ concentration in tap water and commercial drinking water has also been successfully determined with the proposed method. Scanning electrochemical microscopy technique was employed to characterize the photocatalytic performance and heterogenous electron transfer rate of electrodes in situ, further revealing the photoelectrochemical sensing mechanism. Besides determining Co2+ concentration, this approach of enhanced catalytic activity by nanoprecipitation can be further extended to develop a variety of electrochemical, photoelectrochemical and optical sensing platforms for many other hazardous ions and biological molecules. [Display omitted] • A new, simple, and sensitive PEC method for direct Co2+ detection is developed. • The formed CoPi at BiVO 4 -Au surface enhanced PEC water oxidation efficiency. • SECM was employed to further reveal the PEC sensing mechanism. [ABSTRACT FROM AUTHOR]

The pollution of heavy metal ions in water seriously affects the ecosystem and human health. Here, an efficient synergetic photocatalytic-photothermal system is designed by combining a mildly oxidized Ti 3 C 2 (mo-Ti 3 C 2) with a super hydrophilic bamboo fiber (BF) membrane. The mo-Ti 3 C 2 heterojunction promotes the transfer and separation of photoinduced charges and thus enhances the photocatalytic reduction of heavy metal ions (Co2+, Pb2+, Zn2+, Mn2+ and Cu2+). The photoreduced metal nanoparticles with high conductivity and LSPR effect further accelerate the transfer and separation of photoinduced charges, and improve photothermal and evaporative performance. The mo-Ti 3 C 2 -2.4 @BF membrane in Co(NO 3) 2 solution can achieve an excellent evaporation rate of 4.6 kg·m−2·h−1 and a high solar-vapor efficiency of up to 97.5% under the light intensity of 2.44 kW·m−2, which are 27.8% and 19.6% higher than those in H 2 O, respectively, demonstrating the reuse of photoreduced Co nanoparticles. No heavy metal ions are detected in any of the condensed water, and the Co2+ removal rate in the concentrated Co(NO 3) 2 solution is up to 80.4%. The synergetic photocatalytic-photothermal approach on the mo-Ti 3 C 2 @BF membrane provides a new scope for the continuous removal and reuse of heavy metal ions, as well as for obtaining clean water. [Display omitted] • Synergistic photocatalytic-photothermal system was designed for metal ions removal. • Ti 3 C 2 concentrates heavy metal ions by high efficiency water evaporation. • The heterojunction promotes the transfer and separation of photoinduced charges. • Photoreduced nanoparticles promote photothermal effect and charge separation. • The membrane achieves a solar-vapor efficiency up to 97.5% in Co2+ solution. [ABSTRACT FROM AUTHOR]

The growing co-contamination of multiple metal ions seriously influences human health due to their synergistic and additive toxicological effects, whereas the rapid discrimination of multiple heavy metal ions in complex aquatic systems remains a major challenge. Herein, a high- throughput fluorescence sensor array was fabricated based on three gold nanoclusters (GSH-Au NCs, OVA-Au NCs, and BSA-Au NCs) for the direct identification and quantification of seven heavy metal ions (Pb2+, Fe3+, Cu2+, Co2+, Ag+, Hg2+ and As3+) from environmental waters without sample pretreatment other than filtration. At the detection system, three gold nanoclusters with various ligands possessed distinct binding capacities against metal ions and induced aggregation-induced fluorescence enhancement and quenching, resulting in a unique pattern of fluorescence variations. Meanwhile, integrated the collected fluorescence fingerprints with linear discriminant analysis (LDA) and hierarchical cluster analysis (HCA), a discrete database was obtained for the accurate recognition and sensitive detection of metal ions. Under the optimized conditions, the limit of detection (LOD) of the proposed fluorescence sensor array for metal ions detection at nM concentration level along with a satisfactory accuracy. Importantly, our study indicated that the fluorescence sensor array could be widely used as a general platform in environmental monitoring against multiple targets at low concentrations. [Display omitted] • A fluorescence array sensor based on three gold nanoclusters was developed. • The array sensor could realize the identification of seven heavy metal ions. • A discrete database was constructed by integrating collected fluorescence fingerprints. • The proposed array achieved acceptable feasibility in real water samples detection. [ABSTRACT FROM AUTHOR]

The accurate identification and sensitive quantification of heavy metal ions are of great significance, considering that pose a serious threat to environment and human health. Most array-based sensing platforms, to date, utilize nanozymes as sensing elements, but few studies have explored the application of the peroxidase-like activity of clusterzymes in identification of multiple analytes. Herein, for the first time, we developed a clusterzyme sensor array utilizing gold nanoclusters (AuNCs) as sensing elements for five heavy metal ions identification including Hg2+, Pb2+, Cu2+, Cd2+ and Co2+. The heavy metal ions can differentially regulate the peroxidase-like activity of AuNCs, and that can be converted into colorimetric signals with 3,3′,5,5′-tetramethylbenzidine (TMB) as the chromogenic substrate. Subsequently, the generated composite responses can be interpreted by combining pattern recognition algorithms. The developed clusterzyme sensor array can identify five heavy metal ions at concentrations as low as 0.5 μM and their multi-component mixtures. Especially, we demonstrated the successful identification of multiple heavy metal ions in tap water and traditional Chinese medicine, with an accuracy of 100% in blind test. This study provided a simple and effective method for identification and quantification of heavy metal ions, rendering a promising technique for environmental monitoring and drug safety assurance. [Display omitted] • Clusterzyme-based sensor array for multiple heavy metal ions identification. • Heavy metal ions differentially modulate enzyme-mimicking property of clusterzymes. • Accurate identification of heavy metal ions in water and Chinese medicine. [ABSTRACT FROM AUTHOR]

This study reports an efficacious solid-state optical sensor through the synergistic coalescences of an original chromoionophoric probe and a structurally engineered porous polymer monolith for the selective and sensitive colorimetric spotting of ultra-trace toxic mercury ions. The unique properties of the bimodal macro-/meso-pore structured polymer, i.e., poly(AAm-co-EGDMA) monolith, offer voluminous and uniform anchoring of probe molecules, i.e., (Z)-N-phenyl-2-(quinoline-4-yl-methylene)hydrazine-1-carbothioamide (PQMHC). The structure/surface features of the sensory system, i.e., surface area, pore dimensions, monolith framework, elemental mapping, and phase composition, were examined by p-XRD, XPS, FT-IR, HR-TEM-SAED, FE-SEM-EDAX, and BET/BJH analysis. The sensor's ion-capturing ability was established through naked eye color transition and UV-Vis-DRS response. The sensor exhibits a strong binding affinity for Hg2+, with a linear signal response in the concentration range of 0–200 μg/L (r2 >0.999), with a detection limit of 0.33 μg/L. The analytical parameters were optimized to facilitate pH-dependent visual sensing of ultra-trace Hg2+ in ≤ 30 s. The sensor exhibits high chemical/physical stability characteristics, with reliable data reproducibility (RSD ≤1.94 %), while testing with natural/synthetic water and cigarette samples. The proposed work offers a cost-effective and reusable naked-eye sensory system for the selective sensing of ultra-trace Hg2+, with potential prospects of commercialization considering their simplicity, viability, and reliability. [Display omitted] • A renewable polymer monolithic template-based opto-chromogenic sensor for Hg2+ ions. • PQMHC-infused polymer template act as a sensitive colorimetric ion-sensing platform. • Probe-anchored porous polymer monolith facilitates naked-eye detection of Hg2+ ions. • Solid-state colorimetric sensor is low-cost, benign, compact, reusable and reliable. • Sensor is suitable for real-time monitoring of natural and industrial water samples. [ABSTRACT FROM AUTHOR]

Highlights • Recent challenges in MBR and electrochemical processes are discussed. • New configurations of MBR and electrochemical reactors are examined. • Removal of organics, heavy metal ions, micropollutants, and dyes are analyzed. • Low-voltage electrically-enhanced MBRs address the drawbacks of standalone units. • Future prospects are discussed. Abstract Research and development activities on standalone systems of membrane bioreactors and electrochemical reactors for wastewater treatment have been intensified recently. However, several challenges are still being faced during the operation of these reactors. The current challenges associated with the operation of standalone MBR and electrochemical reactors include: membrane fouling in MBR, set-backs from operational errors and conditions, energy consumption in electrochemical systems, high cost requirement, and the need for simplified models. The advantage of this review is to present the most critical challenges and opportunities. These challenges have necessitated the design of MBR derivatives such as anaerobic MBR (AnMBR), osmotic MBR (OMBR), biofilm MBR (BF-MBR), membrane aerated biofilm reactor (MABR), and magnetically-enhanced systems. Likewise, electrochemical reactors with different configurations such as parallel, cylindrical, rotating impeller-electrode, packed bed, and moving particle configurations have emerged. One of the most effective approaches towards reducing energy consumption and membrane fouling rate is the integration of MBR with low-voltage electrochemical processes in an electrically-enhanced membrane bioreactor (eMBR). Meanwhile, research on eMBR modeling and sludge reuse is limited. Future trends should focus on novel/fresh concepts such as electrically-enhanced AnMBRs, electrically-enhanced OMBRs, and coupled systems with microbial fuel cells to further improve energy efficiency and effluent quality. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Sub-lethal levels of heavy metals increase mutation rates and enrich de novo mutants. • The mutants exhibited resistance to multiple antibiotics and hereditary resistance. • Mutations in gens are responsible for specific and multiple antibiotic resistances. • The genetic changes were distinct for mutants induced by different heavy metals. Abstract The emergence of antibiotic resistance is a growing problem worldwide. Numerous studies have demonstrated that heavy metals facilitate the spread of bacterial drug-resistance in the environment. However, the actions and mechanisms of metals at relatively low sub-lethal levels (far below the minimal inhibitory concentration [MIC]) on antibiotic resistance remain unclear. In this study, we investigated the effect of sub-lethal levels of heavy metals [Ag(I), Zn(II), and Cu(II)] on antibiotic resistance and explored the underlying mechanisms. The results demonstrated that sub-lethal levels of metal ions increased the mutation rates and enriched de novo mutants that exhibited significant resistance to multiple antibiotics. The resistant mutants exhibited hereditary resistance after 5-day of sub-culture. Whole-genome analysis revealed distinct mutations in genes involved in multiple drug and drug-specific resistance, as well as genes that are not associated with antibiotic resistance to data. The number and identities of genetic changes were distinct for mutants induced by different metals. This study provides evidence and mechanistic insights into the induction of antibiotic resistance by sub-lethal concentrations of heavy metals, which may enhance the emergence of antibiotic resistance in various environments. More consideration and regulations should be given to this potential health risk for long-standing and harmful heavy metals. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Impacts of alkali-earth metal and heavy metal ions on nitrogen removal were compared. • Availability of Mg(II) significantly enhanced the nitrogen removal efficiency. • Zn(II) and Ni(II) suppressed the nitrogen removal activity of A. arilaitensis. • Ni(II) ion is more inhibitory than Zn(II) under nitrogen removal process. Abstract This study investigated the impacts of alkaline-earth metals [Ca(II), Mg(II)] and heavy metals [Zn(II), Ni(II)] on the nitrogen removal capacity of Arthrobacter arilaitensis Y-10. StrainY-10 was able to tolerate 20 mg/L Ca(II) and its ammonium removal efficiency was 100%. 0.5 mg/L Ca(II) effectively promoted total nitrogen removal from wastewater containing nitrite. Mg(II) supplementation substantially enhanced the bacterial growth and nitrogen reduction. As Mg(II) concentrations increased from 0 to 2 mg/L, the ammonium, nitrate and nitrite removal efficiencies increased by 40.62%, 69.91% and 64.68%, respectively. Although the nitrogen removal ability of strain Y-10 was sharply hindered by Zn(II) and Ni(II), it occurred continuously even when the Zn(II) concentration reached 30 mg/L. However, the ammonium and total nitrogen removal almost stopped at 8 mg/L Ni(II), and the denitrification capacity was lost when the Ni(II) concentration exceeded 1 mg/L. The results demonstrate that Ca(II) and especially Mg(II) could significantly enhance the nitrogen removal capacity of Arthrobacter arilaitensis relative to Zn(II) and Ni(II). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • LXR-BT was synthesized by intercalation of LXR into the layers of bentonite. • Hybridization endows it versatility in adsorbing organic and inorganic pollutants. • It showed a high adsorption capacity of 438.75 mg/g for DCH in water. • Over 99% Hg(II) ions could be removed from a solution of 10 mg/L by LXR-BT. • The abundance of raw material makes LXR-BT an eco-friendly and low-cost adsorbent. Abstract Natural-occurring polymer intercalated inorganic clay composites have received increasing interests in water cleanup for the features of eco-friendliness, cost-effectiveness, and availability. Herein, a new lignin xanthate resin (LXR) intercalated bentonite clay composite (LXR-BT) for the adsorption of representative organic doxycycline hydrochloride (DCH) antibiotic and inorganic Hg(II) in water was created through a feasible process. Structural characterizations by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Thermo gravimetric analysis (TG), and scanning electron microscopy (SEM) confirmed LXR was successfully intercalated between the layers of bentonite clay. The adsorption performance of DCH/Hg(II) by LXR-BT was studied in detail with varied dosage, solution pH, contact time, and initial DCH/Hg(II) concentration. The results indicated that the adsorption capacities of DCH/Hg(II) on LXR-BT were much higher than that on bentonite, and the adsorption kinetics and isotherms followed the pseudo-second-order model and Langmuir model, respectively. X-ray photoelectron spectroscopy (XPS) analysis confirmed the adsorption mechanisms of DCH (or Hg(II)) was mainly due to π-π interaction and hydrogen bonding interaction of DCH (or the complexation of Hg(II)) with the functional groups in the LXR-BT. This study suggested the possibility of LXR-BT as a new cost-effective adsorbent for both organic and inorganic pollutants removal in water. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The UiO-66-NH 2 MOF crystal were synthesized by microwave heating method. • The MOFs were incorporated into the PAN/chitosan nanofibers. • The 10 wt.% MOF was optimum content in nanofibers for metal ions adsorption. • The maximum adsorption capacity of nanofiber was 441.2 mgg−1 for Pb(II) ions sorption. • The flux and Pb(II) ions rejection by MOF loaded-nanofibers were 452 Lm-2 h−1 and 94%. Abstract In the present study, the UiO-66-NH 2 MOF synthesized by microwave heating method was incorporated into the PAN/chitosan nanofibers for the removal of Pb(II), Cd(II) and Cr(VI) ions through the adsorption and membrane filtration processes. The synthesized MOFs and nanofibers were characterized using XRD, BET, FTIR, SEM, and DSC analysis. The effect of UiO-66-NH 2 MOF content (0–15 wt.%), pH (2–7), contact time(5–90 min), metal ions initial concentration (20–1000 mg/L) and temperature (25–45 °C) was studied on the metal ions adsorption using PAN/chitosan/UiO-66-NH 2 nanofibrous adsorbent. The kinetic, isotherm and thermodynamic parameters were evaluated to understand the metal ions adsorption mechanism using nanofibers. The Pseudo-second-order kinetic and Redlich-Peterson isotherm model were well described the experimental sorption data. In the heavy metal ions membrane filtration process, the different parameters such as MOF concentration (2–15 wt.%), membrane thickness (10–70 μm), metal ions concentration (5–50 mg/L), temperature (25–45 °C) and filtration time (1–24 h) were investigated on the performance of PVDF/ PAN/chitosan/UiO-66-NH 2 nanofibrous membrane toward metal ions removal. The high water flux and high metal ions removal within 18 h filtration time showed the high potential of PVDF/ PAN/chitosan/UiO-66-NH 2 membrane for the removal of metal ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

Highlights • A novel thin-film nanocomposite membrane with a NF-like selective layer was prepared for forward osmosis. • The prepared TFN membrane shows an enhanced water permeability without sacrificing the selectivity. • The prepared TFN membrane shows high heavy metal ions rejection in the FO mode. Abstract A novel thin film nanocomposite (TFN) forward osmosis (FO) membrane with a positively charged and nano-functional selective layer has been developed for effective heavy metal ions removal. The selective layer is constructed by penetrating the polydopamine modified zeolitic imidazolate framework (ZIF-8@PDA) in the poly(ethyleneimine)/1,3,5-benzenetricarboxylic acid chloride (PEI/TMC) crosslinked matrix. Compared with the pristine thin film composite (TFC) membrane, the thin film nanocomposite membrane (0.05 wt % nanofillers loading) exhibits a higher water flux (20.8 vs12.8 LMH) without losing of selectivity in terms of J s /J w ratio (0.25 vs 0.20 g L−1) in FO mode. This improvement of the permeability is mainly attributed to the optimized selective layer with good wettability and loose structure. Besides, the modified PDA layer facilitates the affinity between the nanofillers and selective layer, which results in an ideal selectivity. In addition, this modified membrane shows a high heavy metal ion (Cu2+, and Ni2+ and Pb2+) rejection (>96%) in FO mode. Our finding offers a simple and efficient method to enhance the FO performance of membrane by designing the selective layer for treating heavy metal wastewater. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The cationic porous organic polymer was prepared via a catalyst-free reaction. • The material was used as a novel ion exchanger to remove dyes and Pd(II) ions. • The polymer adsorbed anionic pollutants in a high-capacity, fast, and selective way. • The adsorption amount to Pd(II) metal ions is a record-high value. • The breakthrough test showed the potential as an ion exchanger for water treatment. Abstract The emerging ionic porous organic materials have achieved various applications in different fields, however, there is limited study on using them to capture ionic pollutants from water. Here we demonstrate a facile method to prepare a cationic porous organic polymer via catalyst-free Schiff base reaction. The imidazolium-based polymer (ImPOP-1) was constructed through copolymerizing cationic molecules with low-cost benzidine. The as-prepared ImPOP-1 exhibits high capacity (e.g. , 476.2 mg g–1 for Pd (II) and 578.5 mg g–1 for AO7−), excellent selectivity (e.g. , more than 99% removal efficiency for Pd (II) in the presence of 100 times excess of SO 4 2–), and fast kinetics (e.g. , 98.6% removal efficiency within 5 min for Pd (II) ions) to the anionic pollutants including organic dyes and heavy metal ions. The excellent performance on scavenging anionic pollutants from water suggests that ImPOP-1 holds promising potential as an ion exchange material for water remediation. [ABSTRACT FROM AUTHOR]

Highlights • A two-compartment electrodialytic cell was compared to a three-compartment cell. • Multivariate analysis was used to evaluate key characteristics of metal removal. • Acidification of the material suspension is faster in the two-compartment cell. • An important current carrier is Ca2+ in all materials. • Cell choice depends on material characteristics for optimal heavy metal removal. Abstract Electrodialytic remediation can be applied to remove heavy metals from contaminated particulate materials in suspension. The applied electric current is the cleaning agent and the heavy metals are removed by electromigration. In this study, a two-compartment cell was compared to a three-compartment cell, for several contaminated materials such as soils, sediments, mine tailings and ashes and totally 20 experiments were conducted. The pH decrease was faster in the two-compartment cell, but the metal removal was higher in the three-compartment cell since anionic metal species are removed from the material suspension in this cell set-up. For materials with relatively high chloride content, fly ash and harbour sediments, up to 38% of the metals were found in the filtrate in the two-compartment cell. Up to 9% of the current was used to transport heavy metal ions in the experiments and the current was mainly carried by H+ and Ca2+. Even with the lower pH in the two-compartment cell experiments, there was little difference in the percentage of the current carried by the metal ions between the two set-ups. Multivariate analysis showed that the choice of cell set-up depends on the metals targeted by remediation and the material characteristics. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Monodispersed chitosan microspheres were prepared by facile microfluidics technique. • Multi-stage interactions between heavy metal ions and adsorbents were revealed. • High selective adsorption in the present of other competitive ions was demonstrated. • Selectivity mechanism was well illustrated by ionic scale effect and DFT analysis. • The re-adsorption efficiency is still higher than 74% after 5 regeneration cycles. Abstract Many industrial wastewater streams contain heavy metals, posing serious and irreversible damage to humans and living organisms, even at low concentrations due to their high toxicity and persistence in the environment. In this study, high-performance monodispersed chitosan (CS) microspheres were prepared using a simple microfluidic method and evaluated for metal removal from contaminated water. Batch experiments were carried out to evaluate the adsorption characteristics for the removal of copper ions, one representative heavy metal, from aqueous solutions. The inherent advantages of microfluidics enabled a precise control of particle size (CV = 2.3%), while exhibiting outstanding selectivity towards target ions (adsorption capacity 75.52 mg g−1) and fair regeneration (re-adsorption efficiency 74% after 5 cycles). An integrated adsorption mechanism analytic system was developed based on different adsorption kinetics and isotherms models, providing an excellent adsorption prediction model with pseudo-second order kinetics (R2 = 0.999), while the isotherm was fitted best to the Langmuir model (R2 = 0.998). The multi-step adsorption process was revealed via quantitative measurements and schematically described. Selective adsorption performance of CS microspheres in the present of other competitive metal ions with different valence states has been demonstrated and studied by both experimental and density functional theory (DFT) analysis. [ABSTRACT FROM AUTHOR]

Highlights • The characteristics of the most common chelating agents are provided. • Fe(III)-complexes are reduced to Fe(II)-complexes by O 2 − not H 2 O 2. • Stability constants determines the reaction rate of Fe(III)-complexes with H 2 O 2. • The application of chelating agents in the Fenton-related reactions are reviewed. • The generation of OH, O 2 −, and ferryl species are discussed. Abstract To overcome the drawback of low pH requirement of the classical Fenton reaction, researchers have applied chelating agents to form complexes with Fe and enable Fenton reaction at high pHs, which is reviewed in this article. The chelating agents reviewed include humic substances, polycarboxylates, aminopolycarboxylic acids, and polyoxometalates. Ligands affect the reactivity of Fe-complexes by changing their redox potentials, promoting their reaction with H 2 O 2 , and competing with target contaminants for the oxidative species. Fe(III)-complexes are reduced to Fe(II)-complexes by O 2 − not H 2 O 2 , as indicated by their redox potentials. The stability constants of Fe-complexes increase with increasing p K a values of the corresponding ligands and also with increasing charge density of the metal ions. A higher stability constant of Fe(III)-complex indicates higher reaction rate of corresponding Fe(II)-complex with H 2 O 2 and lower reduction rate of Fe(III)-complex to Fe(II)-complex. OH, O 2 −, and ferryl species were reported to be the reactive species on the contaminant removal in the chelate-modified Fenton process. The generation of these species depends on the chelating agents and reaction conditions. The process is very efficient in degrading contaminants, indicating a potential treatment approach for the pollution remediation at natural pH. [ABSTRACT FROM AUTHOR]

Highlights • Ferro-alloy elements could be concentrated in the spinel through controlled cooling. • The Cr-concentrates can be obtained using molten stainless steel slag and dust mixture. • With a higher dust ratio, the Cr and Mn contents in the spinel decrease. • Larger amounts of dust would be advantageous for primary spinel phase formation. • The contents of Fe and Cr are constant in the amorphous regardless of temperature. Abstract The selective concentration of valuable metal cations in Fe t O-Cr 2 O 3 -NiO-MnO-containing stainless steel dust has been studied. The hazardous metal cations Fe, Cr, Ni and Mn could be locally concentrated during the solidification of a molten stainless steel slag and dust mixture from high temperatures by controlling the primary crystalline spinel phase. The nucleation and growth of the primary spinel phase could be controlled by varying the slag to dust mixing ratio and the cooling temperature. Significant redistribution between the primary spinel and amorphous phases could be observed, where the contents of Cr and Mn in the crystalline phase could be increased up to 40% and 10%, respectively, from their initial contents of 5% and 4% in the melt. Using the specified controlled cooling conditions, a primary spinel phase concentrated with Fe-Cr-Ni-Mn could be formed, which could be clearly distinguished and eventually separated from the amorphous matrix. The mixed stainless steel slag and dust samples were quenched at various cooling temperatures and with varying amounts of dust to identify and optimize the crystalline phases formed using SEM-EDS (scanning electron microscopy-energy dispersive spectroscopy) and XRD (X-ray diffraction) analyses. [ABSTRACT FROM AUTHOR]

Biomineralization is an interesting naturally occurring process of forming minerals by microorganisms, which offers an efficient way to sequester heavy metal ions within relatively stable solid phases. In this study, Bacillus cereus Cd01 was selected to investigate effects of self-mediated pH on biosorption and biomineralization of Cd 2+ in whole 72h cultivation period. Results revealed that strain Cd01-mediated pH decrease of the cultivation medium from 7.0 to 6.1 inhibited biosorption of Cd 2+ on Cd01 cells at the initial cultivation period, while an increased pH from 6.1 to 7.4 facilitated biosorption of Cd 2+ on Cd01 cells at the middle and late cultivation period. The reasons were mainly that self-mediated pH altered cell surface hydrophobicity and cell membrane fluidity of strain Cd01. Moreover, biosorption and bioaccumulation of Cd 2+ on Cd01 cells in the period of increased pH promoted biomineralization of Cd 2+ observed by the transmission and scanning electron microscopes. The analyses of energy dispersive spectroscopy, X-ray photoelectron spectroscopy and select area electron diffraction demonstrated that Cd 2+ loaded on Cd01 cells was biomineralized into polycrystalline and/ or amorphous cadmium sulfide and cadmium phosphate. These results suggest that strain Cd01 may play a potential role in biomineralization remediation of heavy metal contaminated soils. [ABSTRACT FROM AUTHOR]

Most of current absorbents are difficult to hold favorable stability and functionality simultaneously when used in condition of high acidity and strong radiation existing in nuclear industry. Herein, a new graphene-synergized 2D covalent organic framework (GS-COF) was obtained via an in-situ loading of a covalent organic framework (TDCOF) on graphene sheets based on a mutual promotion strategy proposed in this work. The corresponding oximation products, o -GS-COF, and also o -TDCOF as a reference object, were respectively prepared subsequently. The results of experiments confirmed that o -GS-COF possesses better acid and irradiation stability than that of o -TDCOF. Adsorption experiments showed that the adsorption capacity of o -GS-COF for uranium is 144.2 mg g −1 , higher than that of GO (92.5 mg g −1 ) and o -TDCOF (105.0 mg g −1 ), and the maximum adsorption capacity reaches 220.1 mg g −1 . In the multi-ions system, o -GS-COF also displayed good selective adsorption property for uranium with SF U/M 35–100 for 5 coexisting divalent metal ions and 14–18 for 5 coexisting trivalent lanthanide ions. The proposed strategy successfully achieved the synergistic improvement of both stability and functionality for the desired adsorbing materials and is of considerable practical utility in the field of design and preparation of reliable high-performance absorbents. [ABSTRACT FROM AUTHOR]

To cope with the increasing environmental issues of red mud, an integrated technological route for its comprehensive utilization was developed through the extraction of valuable components and the synthesis of magnetic 4A-zeolite. To accelerate the crystallization process of the synthesized 4A-zeolite, sodium chloride (NaCl) was innovatively employed under hydrothermal treatment. The effects of various parameters, including mass ratio of red mud/NaOH, alkali fusion temperature, alkali fusion time and molar ratio of NaCl/Al 2 O 3 , were systematically investigated. The results showed that approximately 81.0% Al, 76.1% Si and 95.8% Fe were utilized from red mud using alkali fusion and acid leaching methods. The optimal conditions of the alkali fusion process were determined as: mass ratio of red mud/NaOH = 1/2, alkali fusion temperature of 800 °C, and time of 90 min. Furthermore, when the molar ratio of NaCl/Al 2 O 3 was kept at 1.5, the crystallization time reduced from 240 min to 150 min, and particle size distributions narrowed from 20–100 μm to 1–10 μm. The practical applications in removal of mixed heavy metal ions (Zn 2+ , Cu 2+ , Cd 2+ , Ni 2+ , and Pb 2+ ) from wastewater indicated that the as-synthesized magnetic 4A-zeolite is a promising candidate for heavy metals adsorption. [ABSTRACT FROM AUTHOR]

A facile composite was fabricated via direct assembly of nitrogen and sulfur co-decorated carbon dots with abundant oxygen–containing functional groups on the surface of the positively charged layered double hydroxide (N,S-CDs-LDH). The novel N,S-CDs-LDH demonstrates highly selective bindings (M-S) and an extremely efficient removal capacity for soft metal ions such as Ag + and Hg 2+ ions. N,S-CDs-LDH displayed a selectivity order of Ag + > Hg 2+ >> Cu 2+ >>> Pb 2+ > Zn 2+ > Cd 2+ for their adsorption. The enormous capacities for Hg 2+ (625.0 mg g −1 ) and Ag + (714.3 mg g −1 ) and very high distribution coefficients ( K d ) of 9.9 × 10 6 mL g −1 (C 0  = 20 mg L −1 ) and 2.0 × 10 7 mL g −1 (C 0  = 20 mg L −1 ) for Hg 2+ and Ag + , respectively, place the N,S-CDs-LDH at the top of LDH based materials known for such removal. The adsorption kinetic curves for Hg 2+ and Ag + fitted well with the pseudo-second order model. For Hg 2+ and Ag + , an exceptionally rapid capture with removal ∼100% within 80 min was observed (C ions  = 30 mg L −1 and V/m ratio of 1000). The adsorption isotherms were well described using Langmuir isotherm. The N,S-CDs-LDH was successfully applied to highly efficient removal of Hg 2+ and Ag + from aqueous solutions. [ABSTRACT FROM AUTHOR]

In this paper, we prepared composites by confining S, O co-doped C 3 N 4 short nanotubes (SOT) into the slit holes of expanded graphite (EG). The prepared SOT/EG composites had hierarchical pores. Macroporous and mesoporous were conducive to the permeation of heavy metal ions (HMIs) solution, while microporous were favorable for HMIs capture. In addition, EG had excellent adsorption and conductive properties. By leveraging their synergistic effect, SOT/EG composites could be used for electrochemical detection and removal of HMIs simultaneously. The excellent HMIs electrochemical detection and removal performances were due to the unique 3D microstructure and the increase of active sites such as S and O. When SOT/EG composites were prepared into modified electrodes, the limit of detections (LODs) of Pb2+ and Hg2+ were 0.038 and 0.051 μg L−1 for simultaneous detection and 0.045 and 0.057 μg L−1 for individual detection. When SOT/EG composites were used as adsorbents, the equilibrium adsorption capacity of Pb2+ and Hg2+ solution of 10 mg L−1 could reach 228.0 and 313.1 mg g−1, and the adsorption efficiency was above 90%. Due to the low raw materials cost and simple preparation method, SOT/EG composite is a very promising bifunctional material for HMIs electrochemical detection and removal. [Display omitted] • S, O co-doped GCN short nanotubes confined in the slit holes of expanded graphite. • Doping S and O atoms enhance the coordination and chelation with HMIs. • Hierarchical porous structure boosts the diffusion and permeation of HMIs solution. • SOT/EG composites were low-cost and promising sensing materials and adsorbents. [ABSTRACT FROM AUTHOR]

The effective simultaneous treatment of hazardous waste sludge and complex oil/water emulsions in one way is urgently desired but still a challenging issue. Herein, this work for the first time presents a green and efficient strategy to fabricate an electroplating sludge (ES) derived multifunctional self-supporting membrane for the one-step removal of emulsified oils, soluble metal ions, and anions in complex oily wastewater. Due to low cost of ES and sustainability of the solvent selected in fabrication process, the large-scale application of the membrane is easily to promote. The assembled hierarchical nanostructure endowed robust underwater superoleophobicity of the membrane even under various corrosive aqueous environments, as well as excellent ultra-low oil adhesion and anti-oil-fouling performance, without chemical modification. Significantly, the multifunctional membrane possessed desirable simultaneous separation efficiency for five typical oil-in-water emulsions (>99.4%, high oil/water selective wettability), including crude oil-in-water emulsion with high viscosity (>99.6%), Cu2+ (>96.1%, surface complexation and ionic exchange), and Cl- (>92.7%, electrostatic attraction). Therefore, this green, low-cost, and multifunctional membrane not only allows the large-scale resource utilization of hazardous waste sludge, but also effectively solves the problems of complex oily wastewater purification. [Display omitted] • Hazardous waste ES was recycled to fabricate self-supporting membrane. • ES acts as both substrates and nickel source for in situ construction of nanostructure. • Low-cost ES and green solvent promote large-scale application. • The membrane can separate three-components pollutants contained oily wastewater. [ABSTRACT FROM AUTHOR]

Metal ions and pesticides are extensively used in many industries and agriculture. However, they cause significant environmental pollution and various adverse health effects. Therefore, the development of sensitive and selective techniques to detect them is necessary for human health and the ecosystem. In this paper, we report a novel red-emitting fluorescence probe with a large Stokes shift (∼220 nm) based on rhodamine and isophorone units. The probe shows a ratiometric fluorescence response toward Hg2+ ions; however, Cu2+ ions quench the red fluorescence signal. The decomposition of the probe-Cu2+ complex allows detection of Thiram followed by recovery of the red fluorescence signal of the probe. In addition, the probe shows a good linear response to Hg2+, Cu2+, and Thiram, with detection limits of 122.0 nM, 29.0 nM, and 72.0 nM, respectively. The practical applicability of the probe has been successfully tested in real samples. Moreover, smartphone detection and light-responsive capsule fabrication have been established, for easy and quick detection. The probe possesses very low cytotoxicity and allows visualization of Hg2+ and Cu2+ ions in HeLa cells. Therefore, the present probe is expected to be an effective tool assisting in easy, quick, and reliable detection of Thiram, Hg2+, and Cu2+ ions. [Display omitted] • A red emitting fluorescent sensor (R6I) with large Stokes shift and low cytotoxicity is developed. • R6I shows fluorescence response towards Hg2+, Cu2+ and Thiram • The limits of detection are down to 122 nM for Hg2+, 29 nM for Cu2+, and 72.0 nM for Thiram • The practical performance of R6I is successively performed in the real samples • The probe is effectively applied to bioimaging Hg2+ and Cu2+ in HeLa cells [ABSTRACT FROM AUTHOR]

Heavy metal pollution is causing a great threat to ecological environment and public health, which needs an efficient strategy for monitoring. A portable microfluidic electrochemical sensing system was developed for the determination of heavy metal ions. Herein, the detection of Pb2+ was chosen as a model, and a microfluidic electrochemical sensing chip relying on a smartphone-based electrochemical workstation was proposed for rapid detection Pb2+ with the assistance of thermocapillary convection result from the formed temperature gradient. The 3D Ag-rGO- f -Ni(OH) 2 /NF composites, prepared by one-step hydrothermal method without any Ni precursor salt, were used to further amplify electrochemical signals under the synergistic effect of thermocapillary convection. The thermocapillary convection could accelerate the preconcentration process and shorten the detection time (save 300 s of preconcentration time). The fabricated system exhibited the exceptional competence for monitoring of Pb2+ range from 0.01 μg/L to 2100 μg/L with a low detection limit (LOD) of 0.00464 μg/L. Furthermore, this portable system has been successfully demonstrated for detecting Pb2+ (0.01 μg/L to 2100 μg/L) in river water (LOD = 0.00498 μg/L), fish (LOD = 0.00566 μg/L) and human serum samples (LOD = 0.00836 μg/L), and the results were consistent with inductively coupled plasma-mass spectrometry (ICP-MS). The proposed novel sensing platform provides a cost-effectiveness, rapidly responding and ease-to-use pathway for analysis of heavy metal ions in real samples and shows great potential in point-of-care testing. [Display omitted] • A portable microfluidic sensor was developed for rapid detection of hazardous Pb2+. • Reducing assay time profited from thermocapillary convection promoting ions transfer. • The 3D Ag-rGO- f -Ni(OH) 2 /NF composites were prepared by one-step hydrothermal method. • The 3D Ag-rGO- f -Ni(OH) 2 /NF were used to amplify electrochemical detection signals. • This novel sensing platform provides an effective strategy for real sample detection. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) with unique physical and chemical properties are composed of metal ions/clusters and organic ligands, including high porosity, large specific surface area, tunable structure and functionality, which have been widely used in chemical sensing, environmental remediation, and other fields. Organic ligands have a significant impact on the performance of MOFs. Selecting appropriate types, quantities and properties of ligands can well improve the overall performance of MOFs, which is one of the critical issues in the synthesis of MOFs. This article provides a comprehensive review of ligand design strategies for functional MOFs from the number of different types of organic ligands. Single-, dual- and multi-ligand design strategies are systematically presented. The latest advances of these functional MOFs in environmental applications, including pollutant sensing, pollutant separation, and pollutant degradation are further expounded. Furthermore, an outlook section of providing some insights on the future research problems and prospects of functional MOFs is highlighted with the purpose of conquering current restrictions by exploring more innovative approaches. [Display omitted] • Three ligand design strategies for functional MOFs are systematically presented. • The recent advances of functional MOFs in environmental applications are presented. • The mechanisms of functional MOFs in environmental applications are discussed. • Problems and challenges of functional MOFs by ligand design in future research are proposed. [ABSTRACT FROM AUTHOR]

Currently, antibiotics and heavy metal contaminants have posed a great threat for ecological security and human health. Herein, the lanthanide functionalized ZIF (named ZIF-90-PABA-Eu) is constructed by coordinating with Eu3+ via p-aminobenzoic acid intermediate. Due to the excellent fluorescence properties, the novel fluorescent probe can selectively monitor flumequine based on "turn on" mode. Furthermore, the obtained new material (named ZIF-90-PABA-Eu-Flu) can be used as "turn off" sensor for selective detection of both radioactive and nonradioactive heavy metal ions (UO 2 2+, Ni2+ and Cu2+) which are the main component of nuclear industrial wastewater. ZIF-90-PABA-Eu-Flu shows ultra-short fluorescence response time (3 s) and ultra-low limit of detection (9.0 × 10−3, 1.3 × 10−2 and 6.1 × 10−4 ppm) for three metal ions, which may be attributed to its good affinity with UO 2 2+, Ni2+ and Cu2+. Moreover, principal component analysis (PCA) is applied to distinguish the three metal ions. Additionally, the possible sensing mechanism is investigated by the UV–vis spectra, luminescence lifetimes and theoretical calculation analysis. Based on these results, ZIF-90-PABA-Eu possesses promising potential in practical application and provides insight for the design of novel probes to continuously monitor flumequine, radioactive and nonradioactive heavy metal ions. [Display omitted] • The lanthanide functionalized ZIF (named ZIF-90-PABA-Eu) by post-modification. • The novel fluorescent probe selectively monitor flumequine based on "turn on" mode. • Simultaneously monitor radioactive metal ions (UO 2 2+) and nonradioactive metal ions (Ni2+ and Cu2+). • Ultra-short fluorescence response time and ultra-low limit of detection for three metal ions. • Principal component analysis (PCA) applied to distinguish various quinolones and three metal ions. [ABSTRACT FROM AUTHOR]

Here, the hybrid material of polyaniline/layered double hydroxide@carbonnanotubes (PANI/LDH@CNT) is considered a multifunctional material. Instrumental methods, including FTIR, XRD, TEM, SEM, and TGA/DTA were utilized to characterize PANI/LDH@CNT. The polymerization method created PANI/LDH@CNT as an adsorbent to remove toxic iodine in hexane solution with a capture capacity of 303.20 mg g−1 during 9 h. It is 900 mg g−1 in the vapor phase within 24 h. After three cycles, the PANI/LDH@CNT could be regenerated while maintaining 91.90 % iodine adsorption efficiency. Due to the presence of free amine (-N) groups, OH−, CO 2 H, and π-π conjugated structures in the PANI/LDH@CNT, it is also explored for efficient iodine uptake. It was demonstrated that the pseudo-first-order (PFO) and Langmuir model had the optimum correlation with the kinetic and isotherm data, respectively. Moreover, the use of PANI/LDH@CNT is not only limited to iodine capture; it can also be utilized as a sensitive sensor that displays a fluorescence "turn-off" response for Mn7+ and Cr6+ ions and a fluorescence "turn-on" response in the case of Al3+ ions. The fluorescence intensity of the PANI/LDH@CNT was turned off in the presence of Mn7+ and Cr6+ because of the fluorescence inner filter effect (IFE) mechanism. In contrast, the fluorescence intensity was turned on in the case of Al3+, relying on the chelation-enhanced fluorescence (CHEF) effect mechanism. Under optimal conditions, the limit of detection (LOD) of 51, 59, and 81 nM for Mn7+, Cr6+, and Al3+, respectively. According to the literature, this is probably the first example based on PANI/LDH@CNT as a multifunctional hybrid material employed as an adsorbent for capturing radioactive iodine and as a chemosensor for detecting heavy metal ions in aqueous solutions. [Display omitted] • Ex-situ oxidative polymerization was used to synthesize PANI/LDH@CNT. • The adsorption capacity for I 2(aq) was 303.20 mg g−1 and 900 mg g−1 in I 2(vap). • PANI/LDH@CNT showed a high sensitivity for heavy metal ions detection at ppb levels. [ABSTRACT FROM AUTHOR]

Triazole contaminants in water and soil environments can form complexes with metal ions, and therefore affect the bioavailability and toxicity of some heavy metals. In present study, significant increase of copper (Cu) uptake by earthworm ( Eisenia fetida ) was observed when combined pollution of benzotriazole (BTR) presented in soil. For instance, Cu accumulation in earthworms increased 55% approximately when BTR presented at the BTR/Cu molar ratio of 1:2.5. While the single Cu exposure (at 32 mg kg −1 in soil) resulted in increased malondialdehyde (MDA) content in earthworms from 0.319 to 0.668 nmol mg protein −1 , joint exposure to BTR at BTR/Cu molar ratio of 1:10 significantly decreased the MDA content to 0.405 nmol mg protein −1 . This indicates a potential detoxification effect of BTR to Cu induced oxidative damage in earthworms. Varied Cu subcellular distribution can be observed in earthworms of the single and combined exposure treatments. With the combined exposure of BTR, the proportion of Cu associated with granular fraction, the toxically inert fraction in earthworms, increased from 25% to 39%. This phenomenon can be used to explain the protective effects of BTR against oxidative damage. [ABSTRACT FROM AUTHOR]

Silica-chitosan hybrid beads were synthesized via three different methods to investigate the selective recovery of REE from AMD. The influence of amino/non-amino silanes, high molecular weight/high viscous chitosan and N-/O- based ligands were studied and their effects on REE removal efficiencies were analyzed. The adsorption efficiencies of three various groups of modified beads were inspected with respect to feed pH, in a single and a multi-component system, and their affinities towards the light and heavy rare earth elements (LREE/ HREEs) were interpreted to understand the intra-series REE separation behavior. The focus of the study was mainly directed towards utilizing these fabricated beads for the recovery of valuable REEs from the real AMD obtained at three different sampling depths which was found rich in iron, sulfur and aluminum. Moreover, the selectivity of the beads towards REEs improved with silanized and ligand immobilized gels and their impacts on REE recovery in the presence of competing ions were successfully presented in this paper. Also, the synthesized beads showed rapid REE adsorption and recovery within a process time of 5 min. Group II adsorbents, synthesized by forming silica-chitosan hybrid beads followed by PAN/acac modifications, showed superiority over the other groups of adsorbents. [ABSTRACT FROM AUTHOR]

It is of great practical importance but rarely reported to design a multifunctional scavenger for water purification. In this study, we describe a sophisticated preparation of an inorganic/organic composite sample for the simultaneous removal of anionic dyes and metal ions, as well as disinfection. The sample has a stable structure formed by the covalent connection between a magnetic silica (MS) core and a polyethylenimine derived quaternary ammonium compound (QAC) corona. We characterized the sample in details by SEM, TEM, EDX, FT-IR, XRD, TGA, VSM, and zeta potential. Our QAC-MS sample exhibited superior performance and reusability in the disinfection and adsorption experiments towards acid fuchsin and Cu 2+ . With the virtue of easy separation from solution, our sample should be an ideal candidate for water purification application. [ABSTRACT FROM AUTHOR]

Herein, for the first time, the typical porous Covalent Organic Frameworks (COFs) CTpBD with superior chemical stability and large surface area were applied as sorbents for solid phase extraction of trace ions via flow injection followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. The well-prepared and fully-characterized CTpBD COFs were filled in solid phase extraction cartridge as novel and robust adsorbents for element analysis. Separation and enrichment of Cr (III), Mn (II), Co (II), Ni (II), Cd (II), V (V), Cu (II), As (III), Se (IV), and Mo (VI) was then carried out, and the contents were measured by ICP-MS. Owing to the large surface area and instinctive porous structure of CTpBD, preconcentration of the target trace elements via COF-filled on-line SPE column has achieved low detection limits of 2.1-21.6 ng L −1 along with a wide linearity range at 0.05–25 μg L −1 for all target ions. The relative standard deviations (RSD) of 1.2%-4.3% obtained via 11 parallel determinations at the sample concentration of 100 ng L −1 revealed excellent repeatability of the developed methods Our proposed methods have been successfully utilized for trace element analysis in environmental and food samples. [ABSTRACT FROM AUTHOR]

Present investigation deals with the treatment of deactivated Co-Mn bromide catalyst for the recovery of Co and Mn as Co metal powder and chemical manganese dioxide by an integrated process comprising of a selective metal ion transfer from an aqueous solution containing a mixture of metal ions with a saponified solution of di-2ethyl-hexyl phosphoric acid, followed by selective scrubbing and metal stripping. The pure metal solutions so obtained were subjected to precipitation and hydrothermal treatment to obtain a desired material. The deactivated catalyst was leached by H 2 SO 4 in presence of H 2 O 2 followed by removing Fe, Si etc. The purified leach liquor of composition: 6.9 g/L Co, 9.4 g/L Mn was used for detail study to optimize the best conditions for the separation of Co from Mn. Experimental observations show that the extraction of both increased with increasing equilibrium pH and the concentration of the organic, with a separation factor of about 10, at equilibrium pH of 3. A quantitative extraction of Mn was possible with 20% D2EHPA in three stage counter-current extraction. After Co scrubbing, Mn was stripped with dilute H 2 SO 4 and high pure spherical shaped CMD was produced. Co in the raffinate was recovered as powder by hydrothermal H 2 - reduction. [ABSTRACT FROM AUTHOR]

Propensity towards anti-organic fouling, anti-biofouling property and low rejection of multivalent cation (monovalent counter ion) restricts the application of the state-of-art poly(piperazineamide) [poly(PIP)] thin film composite (TFC) nanofiltration (NF) membrane for the treatment of water containing toxic heavy metal ions, organic fouling agents and microbes. Herein, we report the preparation of thin film nanocomposite (TFNC) NF membranes with improved heavy metal ions rejection efficacy, anti-biofouling property, and anti-organic fouling properties compared to that of poly(PIP) TFC NF membrane. The TFNC NF membranes were prepared by the interfacial polymerization (IP) between PIP and trimesoyl chloride followed by post-treatment with polyethyleneimine (PEI) or PEI-polyethylene glycol conjugate and then immobilization of Ag NP. The IP was conducted on a polyethersulfone/poly(methyl methacrylate)-co-poly(vinyl pyrollidone)/silver nanoparticle (Ag NP) blend ultrafiltration membrane support. The TFNC membranes exhibited >99% rejection of Pb 2+ , 91–97% rejection of Cd 2+ , 90–96% rejection of Co 2+ and 95–99% rejection of Cu 2+ with permeate flux ∼40 Lm −2 h −1 at applied pressure 0.5 MPa. The improved heavy metal ions rejection efficacy of the modified NF membranes is attributed to the development of positive surface charge as well as lowering of surface pore size compared to that of unmodified poly(PIP) TFC NF membrane. [ABSTRACT FROM AUTHOR]

A phosphorylethanolamine-functionalized graphene foam (PNGF) has been proposed as an active filtration material for the capture and removal of heavy metal ions in water. Benefiting from its abundant hydrophilic portion of oxygen, nitrogen and phosphorus groups, the PNGF is super-hydrophilic. The selected heavy metal ions, Pb(II) and Cd(II), could be rapidly and efficiently absorbed within 10 min using the PNGF through a filtration model, which is obviously less time compared with the several hours or even longer time when employing the traditional shaking or stirring model. In addition, the used PNGF filters can be easily reused after a simple, low-cost detachment using HCl to remove the heavy metals, providing a new approach for water purification. [ABSTRACT FROM AUTHOR]

We have developed a simple one-step method to synthesize novel supramolecular polysaccharide composite from cellulose (CEL) and dibenzo-18-crown 6 using ceric ammonium nitrate as initiator. The [CEL + DB18C6] composites obtained retain properties of their components, namely superior mechanical strength (from CEL), excellent adsorption capability for heavy metal ions from DB18C6. More importantly, the [CEL + DB18C6] composites exhibit truly supramolecular properties. By itself CEL and DB18C6 can adsorb heavy metals. However, adsorption capability of the composite was substantially and synergistically enhanced by adding DB18C6 to CEL. That is, the removal percentage value for Cd 2+ , Zn 2+ , Ni 2+ , Pb 2+ and Cu 2+ by [CEL + DB18C6] composites are much higher than removal percentage values of individual CEL and DB18C6 composites. It seems that DB18C6 synergistically interact with CEL to form more stable complexes with heavy metals, and as a consequence, the [CEL + DB18C6] composite can adsorb relatively larger amount heavy metals. The adsorption parameters, such as pH, adsorbent dose, contact time, initial metal ion concentration and temperature were optimized. Desorption studies revealed that the regeneration of modified cellulose saturated with these metallic ions depends on the type and concentration of the regenerating solution (NH 4 Cl, HNO 3 , NaCl and CaCl 2 ). [ABSTRACT FROM AUTHOR]

A highly selective and sensitive determination of Hg 2+ in water samples with bioimaging applications in living cells using a fluorogenic pyrene-amino mercapto thiadiazole (PYAMT) probe is described. The probe PYAMT exhibited three absorption peaks at 333, 348 and 394 nm and emission maxima at 378, 388 and 397 nm (λ ex = 348 nm). It showed significant fluorescent quenching (96%) with I/I 0 = 0.051 upon the addition of 2.5 μM Hg 2+ ion in CH 3 CN(ACN):H 2 O (1:1, v/v; pH 7.2), whereas its fluorescence remained unaltered in the presence of other metal ions. The quenching phenomenon is attributed to the heavy atom effect of Hg 2+ ion followed by electron transfer. The fluorescence intensity decreased linearly against a wide range from 100 nM to 2.5 μM Hg 2+ (R 2 = 0.9937) with a limit of detection as low as 0.35 nM (S/N = 3). The binding stoichiometry ratio of PYAMT-Hg 2+ is proved to be 1:1 by fluorescence and DFT measurements. The sensor possesses high association constant with Hg 2+ ion in the order of 9.08 × 10 5 M −1 and it is also capable of reversibly detecting cysteine with OFF-ON mechanism. Finally, the proposed method is successfully applied to selectively detect Hg 2+ ion in real water samples and bioimaging studies in live cells. [ABSTRACT FROM AUTHOR]

In this paper, we report the development of an environmental friendly process to decontaminate uranium-containing ores and nuclear wastes by using non-fluorinated ionic liquids (ILs). The main advantages of this extraction process are the absence of any organic diluent and extra extraction agents added to the organic phase. Moreover, the process is cost-effective and maybe applied as a sustainable hydrometallurgical method to recover uranium. The distribution ratio ( D U ) and the extraction efficiency (%E) of uranium(VI) (UO 2 2+ ) were found to be dependent on the acidity of the aqueous phase, the extraction time, the alkyl chain length in the ILs, the concentration of the aqueous feed and molar quantity of ILs. The D U value is higher than 600 and the %E is equal to 98.6% when [HNO 3 ] = 7 M. The extraction reactions follows a neutral partition or ionic exchange mechanism depending on nitric acid concentration. The nature of bonding in the extracted complexes was investigated by spectroscopic techniques. The potential use of Mor 1-8 -OP for the separation of UO 2 2+ from a mixture containing transition metal ions M n+ was also examined. The UO 2 2+ ions were separated and extracted efficiently. These ILs are promising candidates for the recovery and separation of uranium. [ABSTRACT FROM AUTHOR]

A novel Ni(II) ion-imprinted polymer (IIP) was synthesized by bulk polymerization for fast removal of Ni(II) ions from aqueous solution. Effects of preparation conditions on adsorption performance were investigated. Diphenylcarbazide (DPC) and N,N-azobisisobutyronitrile (AIBN) were used as ligand and initiator, respectively. Various monomers, solvents, cross-linking agents and molar ratios of template, monomer and cross-linking agent for polymerization were studied to obtain the largest adsorption capacity. The prepared Ni(II)-IIPs were characterized using Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDX) and thermogravimetric analysis (TGA). The elution process has no influence on the three-dimension network structure observed on the surfaces of Ni(II)-IIPs. Ni(II) ions could be eluted from IIPs successfully with HCl solution. Effects of operating time, pH and initial concentration of Ni(II) in aqueous solution on adsorption performance were investigated too. The adsorption equilibrium was reached within 30 min. The maximum adsorption capacity of Ni(II)-IIPs was 86.3 mg g −1 at pH 7.0 with initial Ni(II) concentration of 500 mg L −1 . The adsorption by Ni(II)-IIPs followed a pseudo-second-order kinetic and Freundlich isotherm models. The selectivity coefficients for all Ni(II)/interfering ions are larger than one because of the imprinting effect. The Ni(II)-IIPs also showed high reusability and stability. [ABSTRACT FROM AUTHOR]