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Manipulation of multiemissive luminophores is meaningful for exploring luminescent materials. Herein, we report a soft double salt assembly strategy that could result in well-organized nanostructures and different luminescence based on multiple weak intermolecular interactions thanks to the existence of electrostatic attraction between the anionic and cationic platinum(II) complexes. The cationic complexes B1 and B2 can coassemble with anionic complex A, respectively, and the emission switches from monomeric and excimeric emission to the triplet metal-metal-to-ligand charge transfer (3MMLCT) along with morphology changes from 0-dimensional (0-D) nanospheres to 3-dimensional (3-D) nanostructures. It is demonstrated that an isodesmic growth mechanism is adopted during the spontaneous self-assembly process, and the relative negative ΔG values make the anionic and cationic complex molecules prefer to form aggregates based on π-π stacking, Pt···Pt interactions, and electrostatic interactions. The coassembly strategy between anionic and cationic complexes endows them with multicolor luminescent and apparent color as optical materials for advanced information encryption.
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Protonic ceramic fuel cells (PCFCs) hold potential for sustainable energy conversion, yet their widespread application is hindered by the sluggish kinetics and inferior stability of cathode materials. Here, a facile and efficient reverse atom capture technique is developed to manipulate the surface chemistry of PrBa0.5Sr0.5Co1.5Fe0.5O5+ δ (PBSCF) cathode for PCFCs. This method successfully captures segregated Ba and Sr cations on the PBSCF surface using W species, creating a (Ba/Sr)(Co/Fe/W)O3- δ (BSCFW)@PBSCF heterostructure. Benefiting from enhanced kinetics of proton-involved oxygen reduction reaction and strengthened chemical stability, the single cell using the optimized 2W-PBSCF cathode demonstrates an exceptional peak power density of 1.32 W cm-2 at 650 °C and maintains durable performance for 240 h. Theoretical calculations unveil that the BSCFW perovskite delivers lower oxygen vacancy formation energy, hydration energy, and proton transfer energy compared to the PBSCF perovskite. This protocol offers new insights into advanced atom capture techniques for sustainable energy infrastructures.
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Synthesis of chiral molecules for understanding and revealing the expression, transfer, and amplification of chirality is beneficial to explore effective chiral medicines and high-performance chiroptical materials. Herein, we report a series of square-planar phosphorescent platinum(II) complexes adopting a dominantly closed conformation that exhibit efficient chiroptical transfer and enhancement due to the nonclassical intramolecular C-H···O or C-H···F hydrogen bonds between bipyridyl chelating and alkynyl auxiliary ligands as well as the intermolecular π-π stacking and metal-metal interactions. The spectroscopic and theoretical calculation results demonstrate that the chirality and optic properties are regulated from the molecular level to hierarchical assemblies. Notably, a 154 times larger gabs value of the circular dichroism signals is obtained. This study provides a feasible design principle to achieve large chiropticity and control the expression and transfer of the chirality.
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Piezocatalytic H2O2 production has attracted significant attention as a green alternative to traditional anthraquinone methods with heavy environmental pollution and high energy consumption. However, since the efficiency of piezocatalyst in producing H2O2 is poor, searching for a suitable method to improve the yield of H2O2 is of great interest. Herein, a series of graphitic carbon nitride (g-C3N4) with different morphologies (hollow nanotube, nanosheet and hollow nanosphere) are applied to enhance the piezocatalytic performance in yielding H2O2. The hollow nanotube g-C3N4 exhibited an outstanding H2O2 generation rate of 262 umol·g-1·h-1 without any co-catalyst, which is 1.5 and 6.2 times higher than nanosheets and hollow nanospheres, respectively. Piezoelectric response force microscopy, piezoelectrochemical tests, and Finite Element Simulation results revealed that the excellent piezocatalytic property of hollow nanotube g-C3N4 is mainly attributed to its larger piezoelectric coefficient, higher intrinsic carrier density, and stronger external stress absorption conversion. Furthermore, mechanism analysis indicated that piezocatalytic H2O2 production follows a two-step single-electro pathway, and the discovery of 1O2 furnishes a new insight into explore this mechanism. This study offers a new strategy for the eco-friendly manufacturing of H2O2 and a valuable guide for future research on morphological modulation in piezocatalysis.
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Arsenic pollution of water is one of the severest environmental challenges for human health, and adsorption is the most often used technique in investigations of selective As removal. However, the development of low-cost and easily recoverable adsorbent for aqueous arsenic adsorption remains a challenge. In this work, the α-FeOOH-decorated monolith bamboo composites (α-FeOOH/MB) were fabricated via directly decorating α-FeOOH nanoneedles on the waste bamboo framework without precarbonization. As expected, the as-prepared α-FeOOH/MB exhibits considerably increased adsorption capacity for aqueous arsenic over pure α-FeOOH nanoneedles, with increases of 1.88 and 1.52 times for As(V) and As(III), respectively. Meanwhile, the α-FeOOH/MB composites exhibit positive reusability (recovering 89.73 % and 80.17 % adsorption capacity for As(V) and As(III) after 5 cycles) and are easy to separate after water treatment. Furthermore, the α-FeOOH/MB composites exhibit high arsenic adsorption selectivity even in the presence of competing anions. Overall, the as-obtained α-FeOOH/MB composites, reuse of waste bamboo, are a kind of favorable candidate for arsenic decontamination in practical application owing to the high adsorption capacity, low-cost and facile separation features.
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BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver malignancy. AIM: To predict early recurrence (ER) and overall survival (OS) in patients with HCC after radical resection using deep learning-based radiomics (DLR). METHODS: A total of 414 consecutive patients with HCC who underwent surgical resection with available preoperative grayscale and contrast-enhanced ultrasound images were enrolled. The clinical, DLR, and clinical + DLR models were then designed to predict ER and OS. RESULTS: The DLR model for predicting ER showed satisfactory clinical benefits [area under the curve (AUC)] = 0.819 and 0.568 in the training and testing cohorts, respectively), similar to the clinical model (AUC = 0.580 and 0.520 in the training and testing cohorts, respectively; P > 0.05). The C-index of the clinical + DLR model in the prediction of OS in the training and testing cohorts was 0.800 and 0.759, respectively. The clinical + DLR model and the DLR model outperformed the clinical model in the training and testing cohorts (P < 0.001 for all). We divided patients into four categories by dichotomizing predicted ER and OS. For patients in class 1 (high ER rate and low risk of OS), retreatment (microwave ablation) after recurrence was associated with improved survival (hazard ratio = 7.895, P = 0.005). CONCLUSION: Compared to the clinical model, the clinical + DLR model significantly improves the accuracy of predicting OS in HCC patients after radical resection.
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Poly(heptazine imide) (abbreviated as PHI), a heptazine-based crystalline carbon nitride photocatalyst, has attracted widespread attention in the photocatalytic H2 evolution benefiting from its high crystallinity. Nevertheless, the optical absorption range of the directly synthesized PHI is generally narrow, which severely hinders the utilization of visible light. Much research aimed to extend the optical absorption range of PHI; however, either the optimization degree was insufficient or the synthesis process was cumbersome. Herein, red PHI (RPHI) for improving the photocatalytic H2 evolution was facilely synthesized by the one step method. The optimal RPHI sample possesses an obvious new absorption band of the n â π* electron transition and exhibits a significantly enhanced photocatalytic H2 evolution rate of 169 µmol h-1 (λ > 510 nm) and 46 µmol h-1 (λ > 600 nm), which is about 5 times (λ > 510 nm) and 7.7 times (λ > 600 nm) that of pristine PHI and surpasses most reported RPHIs. This work may promote the development of the PHI photocatalyst for near-infrared photocatalytic H2 production.
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The petrochemical industry is one of the major emission sources of volatile organic compounds (VOCs). However, the current studies have mostly focused on the identification of the chemical characteristics of non-methane hydrocarbon (NMHC) VOCs species from the petroleum refining sub-sector. Research on the characteristics of VOCs components in oxygenated VOCs (OVOCs) species and other important sub-sectors is still lacking. Therefore, eight enterprises at a petrochemical industrial park in the Pearl River Delta region were carefully selected to represent three major subsectors, namely petroleum refining, synthetic materials, and organic chemicals, for the petrochemical industry. The VOCs (including 22 OVOCs species) from stack emissions and fugitive emissions, as well as nearby sensitive sites, were sampled, and the source reactivity (SR), the thresholds of malodor, and the carcinogenic and non-carcinogenic risks were assessed. The main results were as follows:â the VOCs concentrations of the stack emissions from the petrochemical industrial park were between 0.2-46.3 mg·m-3. The VOCs species were greatly affected by the type of after-treatment technology. A major VOC species emitted from the combustion-based after treatments was formaldehyde, whereas the species emitted from the non-combustion-based equipment were acetone, 1,3-butadiene, acrylic, and isobutane. â¡ The fugitive VOCs emissions from the petroleum storage tank area were dominated by alkanes, whereas the other fugitive emission sites and the sensitive sites were dominated by OVOCs such as acetone, formaldehyde, and ethyl acetate. ⢠The SRs were mainly contributed by OVOCs, aromatics, and olefins, with average proportions of 43.1%, 24.2%, and 21.1%, respectively, with the major species being formaldehyde, acetaldehyde, m/p-xylene, ethylene, and toluene. ⣠The malodor appeared both in fugitive emission areas and the sensitive sites. The main odor components were OVOCs such as n-butyraldehyde, propionaldehyde, hexanal, and valeraldehyde. ⤠The non-carcinogenic risks occurred in the fugitive emission areas and the sensitive sites of resin, alcohol, and aldehyde production, which were mainly caused by OVOCs such as free acetaldehyde, acrolein, and propionaldehyde. No carcinogenic risk was found in any of the sampled sites. This research can provide scientific support for the formulation of priority VOCs species-based precise control strategies in petrochemical industrial parks.
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Poluentes Atmosféricos , Petróleo , Compostos Orgânicos Voláteis , Acetaldeído , Acetona , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Formaldeído , Compostos Orgânicos Voláteis/análiseRESUMO
Wastewater-based epidemiology (WBE) has emerged as an effective environmental surveillance tool in monitoring fecal-oral pathogen infections within a community. Congruently, SARS-CoV-2, the etiologic agent of COVID-19, has been demonstrated to infect the gastrointestinal tissues, and be shed in feces. In the present study, SARS-CoV-2 RNA was concentrated from wastewater, sludge, surface water, ground water, sediment, and soil samples of municipal and hospital wastewater systems and related environments in Wuhan during the COVID-19 middle and low risk periods, and the viral RNA copies quantified using reverse transcription quantitative polymerase chain reaction (RT-qPCR). From the findings of this study, during the middle risk period, one influent sample and three secondary effluents collected from waste water treatment plant 2, as well as two samples from Jinyintan Hospital wastewater system influent were SARS-CoV-2 RNA positive. One sludge sample collected from Guanggu Branch of Tongji Hospital, which was obtained during the low risk period, was also positive for SARS-CoV-2 RNA. These study findings demonstrate the significance of WBE in continuous surveillance of SARS-CoV-2 at the community level, even when the COVID-19 prevalence is low. Overall, this study can be used as an important reference for contingency management of wastewater treatment plants and COVID-19 prevention and control departments of Wuhan.
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COVID-19 , Águas Residuárias , Monitoramento Ambiental , Humanos , RNA Viral , SARS-CoV-2RESUMO
OBJECTIVES: To evaluate the effect of the position of microcoil proximal end on the incidence of microcoil dislocation during CT-guided microcoil localization of pulmonary nodules (PNs). METHODS: This retrospective study included all patients with PNs who received CT-guided microcoil localization before video-assisted thoracoscopic urgery (VATS) resection from June 2016 to December 2019 in our institution. The microcoil distal end was less than 1 cm away from the nodule, and the microcoil proximal end was in the pleural cavity (the pleural cavity group) or chest wall (the chest wall group). The length of microcoil outside the pleura was measured and divided into less than 0.5 cm (group A), 0.5 to 2 cm (group B) and more than 2 cm (group C). Microcoil dislocation was defined as complete retraction into the lung (type I) or complete withdrawal from the lung (type II). The rate of microcoil dislocation between different groups was compared. RESULTS: A total of 519 consecutive patients with 571 PNs were included in this study. According to the position of microcoils proximal end on post-marking CT, there were 95 microcoils in the pleural cavity group and 476 in the chest wall group. The number of microcoils in group A, B, and C were 67, 448 and 56, respectively. VATS showed dislocation of 42 microcoils, of which 30 were type II and 12 were type I. There was no statistical difference in the rate of microcoil dislocation between the pleural cavity group and the chest wall group (6.3% vs 7.6%, x2 = 0.18, p = 0.433). The difference in the rate of microcoil dislocation among group A, B, and C was statistically significant (11.9%, 5.8%, and 14.3% for group A, B, and C, respectively, x2 = 7.60, p = 0.008). In group A, 75% (6/8) of dislocations were type I, while all eight dislocations were type II in group C. CONCLUSIONS: During CT-guided microcoil localization of PNs, placing the microcoil proximal end in the pleura cavity or chest wall had no significant effect on the incidence of microcoil dislocation. The length of microcoil outside the pleura should be 0.5 to 2 cm to reduce the rate of microcoil dislocation. ADVANCES IN KNOWLEDGE:: CT-guided microcoil localization can effectively guide VATS to resect invisible and impalpable PNs. Microcoil dislocation is the main cause of localization failure. The length of microcoil outside the pleura is significantly correlated with the rate and type of microcoil dislocation. Placing the microcoil proximal end in the pleura cavity or chest wall has no significant effect on the rate of microcoil dislocation.
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Marcadores Fiduciais , Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Radiografia Intervencionista/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Feminino , Marcadores Fiduciais/efeitos adversos , Marcadores Fiduciais/estatística & dados numéricos , Migração de Corpo Estranho/diagnóstico por imagem , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Masculino , Nódulos Pulmonares Múltiplos/cirurgia , Cavidade Pleural/diagnóstico por imagem , Estudos Retrospectivos , Nódulo Pulmonar Solitário/cirurgia , Cirurgia Torácica Vídeoassistida , Parede Torácica/diagnóstico por imagemRESUMO
A selective cyclization of unsaturated barbiturates and amidines promoted by N-bromosuccinimide has been successfully developed to afford a vast variety of 5,4'-imidazolinyl spirobarbiturates in moderate to good yields. The present protocol features broad substrate scope, facile work-up procedure and mild reaction conditions, providing a novel strategy for the highly selective and efficient construction of structurally diverse spiroimidazolines.
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Droughtmaster is a tropical breed of beef cattle that can survive in hot climates and easily adapt to torrid environments. These traits are important in livestock breeding. In this study, we genotyped five single-nucleotide polymorphisms (SNPs) of the AHSA2 gene from 190 cattle belonging to three different breeds (Droughtmaster, Angus and Simmental) by using snapshot technology. This work aimed to identify the valuable molecular marker of heat resistance in cattle. Results showed that Droughtmaster exhibited higher expected heterozygosity and polymorphic information content compared with the two other breeds. The AHSA2-1 locus deviated from the Hardy-Weinberg equilibrium in the Droughtmaster breed (P < 0.05). Two SNPs in Droughtmaster diverged significantly from Angus and Simmental. The SNPs were identified as AHSA2-3 and AHSA2-4, which were closely linked to the three breeds based on pair-wise FST. AHSA2-4 involved a missense mutation. In summary, the GG genotypes in AHSA2-3 and AHSA2-4 may be candidate genotypes associated with heat resistance traits and may serve as valuable genetic markers for breeding of heat-tolerant beef cattle in the future.
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Marcadores Genéticos , Técnicas de Genotipagem/métodos , Chaperonas Moleculares/genética , Polimorfismo de Nucleotídeo Único , Seleção Genética , Animais , Cruzamento , Bovinos , Genótipo , Fenótipo , Característica Quantitativa HerdávelRESUMO
Nano-structuring of polymeric carbon nitride (PCN) is an important strategy to improve its photocatalytic performance, while facile and green methods are scarce yet. Herein, we proposed a novel steam-assisted method to prepare holey PCN nanosheets in one step. Only a green gas template, i.e. steam, decomposed from the recyclable steam source Mg(OH)2 is needed for PCN nano-structuring. Moreover, in situ element doping of nano-structured PCN can be synchronously realized via this method. The holey PCN nanosheets and doped counterparts have boosted visible-light photocatalytic H2 evolution activities 12-35 times that of bulk PCN, benefitting from enlarged specific surface area, suppressed photogenerated electron-hole recombination and prolonged charge carrier lifetime. Steam-assisting may be a useful strategy for the facile and green synthesis of other nanosized PCN materials.
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Tungstate enrichment in aquatic systems may cause negative environmental and health effects. This study addresses tungstate removal from aqueous solution by nanocrystalline iowaite, an iron-bearing layered double hydroxide, which has not been used for treatment of tungstate-rich waters so far. Tungstate sorption experiments were conducted with various contact times, temperatures, initial tungstate concentrations (0.001-2â¯mM), and solution pH values (2-13), the results indicating that iowaite sorbed aqueous tungstate effectively and quickly, and the sorption maximum can be up to 71.9â¯mg/g. Moreover, the tungsten sorption capacity keeps nearly constant at a wide pH range from 3 to 11. Duo to its pH buffering effect, the alkaline conditions were generated by the addition of iowaite, which are favorable for the removal of aqueous tungstate because the polymerization of tungstate can be prohibited at alkaline pH values. Zeta potential, XRD and XPS analyses were employed to clarify the sorption mechanisms, and it was concluded that tungstate was sorbed via its exchange with the chloride originally intercalated into iowaite interlayers as well as its stronger inner-sphere complexation with the Fe atoms located in iowaite layers. Nanocrystalline iowaite is suitable for treating both tungstate-bearing natural waters with moderately high tungstate concentrations and industrial wastewaters extremely rich in tungstate.
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Modelos Químicos , Compostos de Tungstênio/química , Poluentes Químicos da Água/química , Adsorção , Cloretos/química , Concentração de Íons de Hidrogênio , Hidróxidos/química , Ferro , Compostos de Tungstênio/análise , Água/química , Poluentes Químicos da Água/análiseRESUMO
The incidence of gestational diabetes mellitus (GDM) has increased dramatically amongst multiethnic population. However, how gestational diabetes mellitus damages the developing embryo is still unknown. In this study, we used yolk sac membrane (YSM) model to investigate angiogenesis in the developing chick embryo. We determined that in the presence of high glucose, it retarded the growth and extension of the embryonic vascular plexus and it also reduced the density of the vasculature in yolk sac membrane model. Using the same strategy, we used the chorioallantoic membrane (CAM) as a model to investigate the influence of high glucose on the vasculature. We established that high glucose inhibited development of the blood vessel plexus and the blood vessels formed had a narrower diameter than control vessels. Concurrent with the abnormal angiogenesis, we also examined how it impacted cardiogenesis. We determined the myocardium in the right ventricle and left atrium were significantly thicker than the control and also there was a reduction in glycogen content in cardiomyocytes. The high glucose also induced excess reactive oxygen species (ROS) production in the cardiomyocytes. We postulated that it was the excess reactive oxygen species that damaged the cardiomyocytes resulting in cardiac hyperplasia.
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Membrana Corioalantoide , Desenvolvimento Embrionário/efeitos dos fármacos , Glucose/farmacologia , Miócitos Cardíacos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saco Vitelino , Animais , Embrião de Galinha , Membrana Corioalantoide/metabolismo , Membrana Corioalantoide/patologia , Glucose/metabolismo , Hiperplasia/induzido quimicamente , Hiperplasia/embriologia , Hiperplasia/patologia , Miócitos Cardíacos/patologia , Saco Vitelino/metabolismo , Saco Vitelino/patologiaRESUMO
This study sought to establish the effectiveness of water washing pre-treatment on the quality of municipal solid waste incineration (MSWI) fly ash (FA) for reuse and solidification or stabilization (S/S). Initial analysis of the FA sample shows that it did not meet the USEPA-1311 toxicity characteristic leaching procedure (TCLP) regulatory limits of 2011. As a result, a two-stage water washing process was carried out an attempt to improve the quality of the MSWI FA. After the washing pre-treatment, the heavy metals in the FA sample met the regulatory limits, thereby making it non-toxic for reuse or safe disposal. The leachate from the washing process also passed regulatory standards of China (GB 8978 - 1996) and the 2011 USEPA-1311. The washing process successfully removed more than 98% of each heavy metal under study. The process was excellent at removing cadmium (99.99%) and very good at removing the rest of the heavy metals. The 28-day compressive strength increased as the quantity of FA decreased. Also, all the heavy metals in the samples prepared with the pre-treated FA met the USEPA-1311 TCLP regulatory limit for reuse and safe disposal. The heavy metals leachability and compressive strength tests showed that the effect of cement-based S/S was largely influenced by its quantity in the samples. The highest compressive strength was attained by using 55% of the FA as replacement for cement. However, FA replacements of up 70% also yielded good results that met the 1989 USEPA standard of 0.34 MPa (50 psi).
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Incineração , Metais Pesados/análise , Eliminação de Resíduos , Carbono , China , Cinza de Carvão , Material Particulado , Resíduos SólidosRESUMO
Pre-treatment process carried out on raw municipal solid waste incineration (MSWI) fly ash (FA) sample that did not comply initially with the USEPA method 1311 toxicity characteristic leaching procedure (TCLP) regulatory limits of 2011 reduced its chloride and heavy metal content appreciably, thereby making it compliant with the aforementioned regulatory requirement. More than 98% of each heavy metal was successfully removed. The process was excellent in removing cadmium (Cd) (99.99%) and very good at removing the rest. About 99.96% of Cu was eliminated, 99.96% of cobalt (Co), 99.95% of Zn, 98.61% of Cr, and 98.12% of nickel (Ni). Also, the leachate resulting from these pre-treatment steps met the China (GB 16889-2008) and USEPA method 1311 regulatory standards for safe discharge. The density and compressive strength of all the samples prepared increased as the FA content decreased. The compressive strength of all the samples passed the 1989 USEPA-recommended value of 0.34 MPa (50 psi), thereby making them suitable for industrial application. The sample that attained the highest compressive strength (2.08 MPa) after 28 days of curing incorporated 55% fly ash (FACS55), while the one with the least compressive strength (0.65 MPa) after the same period was made from only fly ash (FACS100). Moreover, the concentration of heavy metals in all the samples generally decreased with the FA content. Chromium was not detected in all the samples, thereby making this an excellent method for its immobilization. From the leachability test results, all the samples prepared met the USEPA method 1311 TCLP regulatory limits.
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Cinza de Carvão/análise , Incineração/métodos , Metais Pesados/análise , China , Força Compressiva , Materiais de Construção , Resíduos SólidosRESUMO
Fly ash (FA), a product of municipal solid waste incineration (MSWI), has been classified as a kind of hazardous waste due to its high content of heavy metals. FA may be reused in the construction industry or disposed of at landfill sites, and thus poses threats to both the environment and human health. This study sought to establish a scientific basis for accurate selection of suitable pH storage conditions for the FA. We evaluated the potential of MSWI FA sample from the Xinghuo waste incineration power plant, Wuhan, to solidify/stabilize the heavy metal (Cu, Pb, Zn, Cr, Cd, As and Mn) contents, when leached under different pH conditions. The concentration of a heavy metal in the leachate was assumed to inversely reflect the extent of its solidification/stabilization (S/S). The study findings showed that the raw FA contained higher levels of the heavy metals, which were above the acceptable limits. Extremely acidic conditions favoured heavy metal leaching compared to extremely alkaline conditions. The extent of S/S of heavy metals was generally very low under highly acidic conditions (pH ≤ 4), but increased with increasing pH. All the metals solidified/stabilized in pH media of 5-11, except Zn which was detected in the entire pH range. We conclude that changing landfill conditions which can affect the pH environment, will increase heavy metal leaching when the pH ≤ 4. As a result, waste which was initially classified as non-hazardous may later pose harmful risks to both humans and the environment alike. We propose pH of 5-11 as the optimum pH range for the treatment, reuse, and disposal of the ash sample.
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Cinza de Carvão , Incineração , Eliminação de Resíduos , Carbono , Concentração de Íons de Hidrogênio , Metais Pesados , Material Particulado , Resíduos SólidosRESUMO
Nanocrystalline iowaite, a Mg/Fe-based layered double hydroxide (LDH) intercalated with chloride, was synthesized to evaluate its performance for arsenic removal from water and to investigate the contributing dearsenication mechanisms. It is characterized by fast arsenic sorption rates and has a much higher arsenic uptake capacity than other LDHs that are commonly used for water dearsenication. The surface adsorption of the solution arsenic onto the iowaite samples and the anion exchange of the arsenic in solution with chloride, which is originally in the iowaite interlayers, are the primary mechanisms for the uptake of arsenic by iowaite. In addition to the Coulombic attraction between arsenate/arsenite and positively charged layers of iowaite, the inner-sphere complexation of arsenic with Fe (instead of Mg) in the iowaite layers is responsible for the formation of more stable and stronger arsenic bonds, as indicated by both XPS and EXAFS analyses. Specifically, bidentate-binuclear and monodentate-mononuclear As-Fe complexes were detected in the arsenate removal experiments, whereas bidentate-mononuclear, bidentate-binuclear, and monodentate-mononuclear As-Fe complexes were present for the arsenite-treated iowaite samples. This study shows that nanocrystalline iowaite is a promising, low-cost material for arsenic removal from natural arsenic-rich waters or contaminated high-arsenic waters.