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In this study, Fenton-like chain reaction is constructed by coupling nanoscale tungsten powders (nW0) and peroxydisulfate (PDS). The nanoscale tungsten powders/peroxydisulfate (nW0/PDS) system exhibits a high oxidation efficiency toward diverse pollutants and expands the effective pH range up to 9.8. Results reveal •OH and sulfate radical (SO 4 •−) were confirmed to be responsible for 4,4′-ethylidenebisphenol (EBP) degradation, especially •OH. The corrosion process of nW0 results in the in-situ production of H 2 O 2 and the transient-state tungsten species (W (x, x < VI)), initiating the reaction of H 2 O 2 and tungsten species to generate •OH. PDS can accelerate nW0 corrosion to enhance the Fenton-like reaction, and can be activated by tungsten species (nW0 and W (x, x < VI)) to produce •OH and SO 4 •−. Integrated the analysis results of LC-QTOF-MS/MS, EBP degradation pathways were proposed. This study reveals the high oxidation efficiency over a wide pH range in the nW0/PDS system and provides new insight into the tungsten species induced Fenton-like reaction. [Display omitted] • The nW0/PDS system exhibits high oxidation efficiency over a wide pH range. • The stepwise oxidation between nW0 and dissoved oxygen in-situ produces H 2 O 2. • •OH and SO 4 •− are generated by the tungsten species induced Fenton-like reaction. • PDS accelerates the corrosion of nW0 and the Fenton-like reaction. • Degradation process of EBP was proposed based on LC-QTOF-MS/MS results. [ABSTRACT FROM AUTHOR]

Industrial and disinfection wastewater typically contains high levels of organic pollutants and residue hydrogen peroxide, which have caused environmental concerns. In this work, dual‐asymmetric MnO2@polymer microreactors are synthesized via pollutant polymerization for self‐driven and controlled H2O2 decomposition. A hollow and asymmetric MnO2 nanotube is derived from MnO2 nanorods by selective acid etching and then coated by a polymeric layer from an aqueous phenolic pollutant via catalytic peroxymonosulfate (PMS)‐induced polymerization. The evolution of particle‐like polymers is controlled by solution pH, molar ratios of PMS/phenol, and reaction duration. The polymer‐covered MnO2 tubing‐structured micromotors presented a controlled motion velocity, due to the reverse torque driven by the O2 bubbles from H2O2 decomposition in the inner tunnels. In addition, the partially coated polymeric layer can regulate the exposure and population of Mn active sites to control the H2O2 decomposition rate, thus avoiding violent motions and massive heat caused by vigorous H2O2 decomposition. The microreactors can maintain the function of mobility in an ultra‐low H2O2 environment (<0.31 wt.%). This work provides a new strategy for the transformation of micropollutants to functional polymer‐based microreactors for safe and controlled hydrogen peroxide decomposition for environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe(III)/Fe(II) cycle enhanced by light, electricity, reductants, oxidants and contaminants were clarified. • Roles and mechanisms of chelate agents and carbon materials in electron donation were summarized. • Electrons donated by reductants showed the best pollutant degradation and pH adaptability. • Enhanced Fe(III)/Fe(II) cycle by reductants shows the similar degradation rate in homogeneous and heterogeneous systems. Low Fe(II) generation is the key limitation for Fenton process, the solution is to provide electrons to accelerate Fe(III) reduction. Many technologies were currently developed to enhance Fenton reactions, yet some mechanisms of the enhanced processes were reported to be inconsistent and the most promising approach remains to be identified. This work systematically reviewed the current strategies to promote Fe(III)/Fe(II) cycle based on electron donors, which were classified into five categories according to electrons being provided by photo, electricity, reductants, oxidants and target contaminants, labelled as e-PF, e-EF, e-Re, e-Ox and e-TC, respectively. Principles of each enhanced Fenton process were clarified. Chelate agents were widely used in the e-Re, e-PF, e-Ox, e-EF, e-TC Fenton processes. Roles of chelate agents like carboxylates, natural antioxidants in all the enhanced Fenton processes were reviewed. Chelate agents with reducing property like tannic acid, tea polyphenols and catechin were found to increase the most degradation rate of target pollutants. Carbon-based materials are another widely used catalysts in Fenton process. The same carbon-based catalysts can play different roles via distinct mechanisms during electron donation in the e-Re, e-Ox, e-TC, and e-PF processes, which were all clearly elucidated in this work. The stability of the catalysts and the pH adaptability of each approach followed the trend of e-PF > e-Re > e-Ox > e-TC. In addition, Fenton process enhanced by the e-Re exhibited the best performance on pollutant degradation. Through comprehensive consideration of pollutant degradation, catalyst stability and pH adaptability, e-Re might be the most promising enhanced Fenton process. Development of reductants that can supply electrons to heterogeneous iron would be necessary for future practical application. [ABSTRACT FROM AUTHOR]

Review: composition, preparation, optimization and application in water splitting, solar cells, degradation of pollutants, and CO2 conversion; 79 refs. [ABSTRACT FROM AUTHOR]

• A highly efficient ECO system was constructed with low current for pollutant degradation. • Singlet oxygen (1O 2) is the predominant active substance in the ECO system. • Decontamination and sterilization can be simultaneously realized in the ECO system. • Satisfactory COD and TOC removal can be achieved for real hospital wastewater treatment. Herein, this work investigated an electrocatalytic ozonation (ECO) strategy using stainless steel-graphite plates as cathode–anode for the degradation of the pharmaceutical pollutant dexamethasone (DXMS) and the treatment of real hospital wastewater. The reaction kinetic constant of the ECO degradation of DXMS (0.387 min−1) was 4 times higher than that of single ozone (0.087 min−1). The established efficient ECO system successfully degraded pharmaceutical contaminants and had excellent bactericidal effects against pathogenic microorganisms (Escherichia coli). The results of scavenging experiments, chemical probe experiments, and electron paramagnetic resonance (EPR) analysis indicated that the newly generated 1O 2 in the ECO system achieved the synergistic effect of the combined EC-ozonation process. More to the point, the ECO system has a high removal rate of chemical oxygen demand (COD) and total organic carbon (TOC) for real hospital wastewater treatment. After 60 min treatment of the ECO system, the COD removal of hospital wastewater ranged from 70 % to 88.91 %, and the TOC removal ranged from 52.05 % to 71.81 %. The ECO system developed in this work has the capacity for simultaneous degradation of pharmaceutical contaminants and sterilization of pathogenic microorganism for hospital wastewater treatment. [ABSTRACT FROM AUTHOR]

Sulfidated zero-valent iron (SZVI) has been widely used in controlling organic pollutants. However, the significant decrease in catalytic activity of SZVI-based Fenton-like systems under neutral and alkaline conditions remains a large problem. Herein, it was found that surface structure regulation of SZVI with H 2 O 2 (HT-SZVI) greatly enhanced its reactivity and efficiently activated H 2 O 2 to oxidize various organics in a wide pH range. The HT-SZVI/H 2 O 2 system exhibited a pH self-regulation capability that stabilized the eventual solution pH at ∼3.5 at the initial pH of 3.0–9.0. The excellent oxidation performance was primarily attributed to surface-bound •OH produced from H 2 O 2 activation by surface Fe(II) sites on HT-SZVI. Additionally, dissolved Fe(II) converted from surface Fe(II) induced proton generation to self-regulate pH. Newly formed high proton-conductive FeS and Fe 3 O 4 shells accelerated the transfer of accumulated protons in solution to iron core to produce Fe(II), enabling efficient proton consumption-regeneration cycle and enhancing •OH production. [Display omitted] • H 2 O 2 pre-corrosion of SZVI greatly modify its structure and surface properties. • Fe(II) (aq) induced the proton production and self-constructed acidic environment. • Fe(II) (s) contributed to H 2 O 2 activation to continuously produce surface-bound •OH. • Newly formed high proton-conductive FeS and Fe 3 O 4 shells boosted the proton cycle. • A durable pH self-regulation effect was maintained in the oxidation process. [ABSTRACT FROM AUTHOR]

A novel "ferrate/percarbonate (Fe(VI)/SPC) co-oxidation process" was used to treat ciprofloxacin (CIP) and various micropollutants (MPs), which owned better performance than mixture of Fe(VI), Na 2 CO 3 and H 2 O 2. The mechanism investigation found that the low-concentration H 2 O 2 (1–2 µM) released by SPC can promote the high-valent iron intermediates (Fe(IV)/Fe(V)) of Fe(VI) to the MP oxidation, and Fe(VI) products can also activate SPC to produce hydroxyl radical (·OH). The interactive activation of Fe(VI) and SPC was realized, which retained the high selectivity of Fe(VI) to electron-rich pollutants, and also made up the oxidation of electron-deficient pollutants through •OH, improving the degradation effect of various MPs by 20–30%, and the rate constant was increased by 1 to 3 times. Moreover, non-purgeable organic carbon (NPOC) determination confirmed that •OH participation reduced the NPOC value of CIP from 5.43 mg/L to 4.37 mg/L. The transformation pathway of CIP showed that Fe(VI)/SPC resulted in more hydroxylation intermediates of CIP than Fe(VI) alone. Acute toxicity assays found that the photoinhibition rate of CIP treated with Fe(VI) alone was 14.5%, while the sample treated with Fe(VI)/SPC showed no significant photoinhibition effect, which proved that the new process had good detoxification properties for CIP. [Display omitted] • The interaction between SPC and Fe(VI) formed both·OH and Fe(IV)/Fe(V). • Low-concentration H 2 O 2 released by SPC improved the electron utilization of Fe(VI). • The·OH enables CIP to generate hydroxylation products possessing reduced toxicity. • SPC/Fe(VI) process is suitable for oxidation of electron rich and electron deficient pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CuS-assited Fe(III)/PAA process was developed to enhance PAA activation effectively for BPA degradation. • OH, O 2 ∙ - , CH 3 C(O)O•, CH 3 C(O)OO• and Fe(IV) were identified as reactive species. • Cu(I), S 2 2- , and S2− were determined to be catalytic sites of CuS responsible for the promotion of PAA activation. • The CuS/Fe(III)/PAA process exhibited excellent degradation performances toward various contaminants. • Water matrices performed limited effects on BPA degradationthe by the CuS/Fe(III)/PAA process. Peracetic acid (PAA), as a promising synthetic organic acid disinfectant, is widely used in advanced oxidation processes to produce radicals for micropollutant abatement. While PAA activation driven by common Fenton-like processes suffers from the slow iron cyclic conversion and production of ferric sludge. This study introduces a metal sulfide, i.e., CuS, to assist the Fe(III)-induced PAA activation via multiple pathways, including the direct PAA activation and Fe(II)/Fe(III) cyclic conversion acceleration, termed as the CuS/Fe(III)/PAA process, to produce •OH, O 2 •−, Fe(IV), CH 3 C(O)O•, and CH 3 C(O)OO•, capable of degrading bisphenol A (BPA), one of representative endocrine disruptors in wastewater, thus overcoming the limitation of conventional Fenton-like processes. Cu(I), S 2 2−, and S2− are determined to be catalytic sites of CuS responsible for the promotion of PAA activation. The CuS/Fe(III)/PAA process exhibits excellent degradation performances under acid conditions and performed high reactivities toward the degradation of various contaminants. The introduction of metal sulfide into the Fe(III)/PAA process improves the PAA activation and micropollutant degradation and reduces accumulation of iron sludge. Of particular significance is that water matrices performed limited effects on the BPA degradation, suggesting the potential of CuS/Fe(III)/PAA process to degrade micropollutants in real water treatment. [ABSTRACT FROM AUTHOR]

Among all homogeneous catalysts, cobalt ions show the highest catalytic performance for the activation of peroxymonosulfate (PMS). Herein, we report a Co2+/PMS/H 3 BO 3 system that can effectively generate reactive oxygen species (ROS) with ultra–low Co2+ dosage (5 μg/L). Co2+/PMS/H 3 BO 3 system showed ultrafast reactivity and wide applicability for various pollutants. Sulfamethoxazole (SMX, 2 mg/L) could be completely removed within 5 min, and the corresponding k obs reached up to 1.1239 min−1. The introduction of H 3 BO 3 significantly promoted the generation of ROS. The turnover frequency (TOF) calculated through dividing k obs by the cobalt ions concentration is as high as 224.78 min−1, which is much higher than most of the current research. Through a series of theoretical and experimental analyses, the complex of H 2 BO 3 −–MS (HSO 5 B(OH) 3 –) was inferred to be the key substance that led to the excellent performance of the system. This work provides new insights into the Co2+/PMS system in the presence of borate buffer. [Display omitted] • Trace cobalt(II) (5 μg/L) can efficiently activate PMS in the presence of boric acid. • The corresponding k obs value reached up to 1.1239 min−1 in Co2+/PMS/H 3 BO 3 system. • H 2 BO 3 −-PMS was the key substance that caused the excellent performance of the system. • Co2+/PMS/H 3 BO 3 system showed wide applicability for various pollutants. • This study provides novel insights into the Co2+/PMS system in borate buffer. [ABSTRACT FROM AUTHOR]

Ultrafiltration membranes are usually used to remove organic pollutants. However, the organic contaminants trapped in the membrane pores and on the membrane surface would limit the reuse of membranes. In this study, polyacrylic acid grafted polyethersulfone membrane was prepared; CdS was then generated in-situ on the membrane surface by subsequently immersing the membrane in Cd2+ and S2− solutions to fabricate photocatalytic composite membranes. Scanning electron microscopy and X-ray photonic energy spectroscopy revealed that the generated CdS were uniformly deposited on the surface of the membrane. The obtained membrane could effectively chemisorb rhodamine B (RhB) dye in dark, and show good photocatalytic degradation performance for RhB under visible irradiation. Meanwhile, the received membranes exhibited enhanced photocatalytic degradation performance compared with the membrane prepared by blending doping method, and displayed better removal performance (77.8 %) in the pH = 7 and low concentration (10 mg/L) RhB solution. Moreover, the degradation and removal ratio could still be stable at over 70 % after 3 cycles. In addition to degrading RhB, the composite membrane also exhibited good photocatalytic degradation for antibiotic organic pollutants. Then, free radical capture experiments showed that the photocatalytic degradation of the membrane was mainly derived from the superoxide anion free radicals. Besides, the prepared membrane also exhibited excellent RhB rejection and fast photocatalytic self-cleaning performances under visible light. Thereby, the photocatalytic composite membrane effectively solved the problem of the easy fouling of ultrafiltration membrane, and showed high potential applications in wastewater remediation. [Display omitted] • The photocatalytic composite membranes were prepared by surface modification and in-situ generation of CdS. • The uniform deposition of CdS on the surface of the membrane effectively solved its agglomeration and embedding. • The membrane displays effective photocatalytic self-cleaning performances for the removal of organic pollutants. • The photocatalytic composite membrane showed great application potential in wastewater remediation. [ABSTRACT FROM AUTHOR]

• •OH and O 2 •− were not the active oxidants in Fe(VI) and Fe(VI)−H 2 O 2 systems. • Density functional theory calculations revealed the two-electron transfer relationship between Fe(VI) and H 2 O 2. • The mechanism of in-situ and ex-situ H 2 O 2 activation of Fe(VI) was systematically revealed. • The characters of peroxide activation of Fe(VI) were proposed. • The Fe(VI)−H 2 O 2 system is a promising technology for degradation of organic contaminants. Recently, several studies have been conscious of the promotion effect of hydrogen peroxide (H 2 O 2), a self-decay product of ferrate (Fe(VI)), on Fe(VI) to oxidize contaminations, but the pivotal activation mechanism has not been thoroughly evaluated. This work aims to compare and reveal the promoting mechanism of H 2 O 2 in Fe(VI) and Fe(VI)−H 2 O 2 processes, and to illustrate the practical use potential of Fe(VI)−H 2 O 2 system. Many lines of evidence verified the involvement of •OH and O 2 •− in pollutant degradation were excluded in Fe(VI) and Fe(VI)−H 2 O 2 systems, meaning that high dosage of H 2 O 2 cannot trigger an activation pathway different from in-situ H 2 O 2. The better oxidation performance of the Fe(VI)−H 2 O 2 system than Fe(VI) alone was ascribed to the catalytic role of in-situ and ex-situ H 2 O 2 , which can directly and/ or indirectly facilitate the formation of Fe(IV) and Fe(V). Considering the structural similarity of peroxymonosulfate (PMS) and peroxydisulfate (PDS) with H 2 O 2 as well as their universality in water pollutant remediation, the oxidation properties and reactive oxidants of Fe(VI)−PMS and Fe(VI)−PDS processes were also examined. Besides, the Fe(VI)−H 2 O 2 system suffered from less restriction by inorganic ions and natural organic matter, and exhibited satisfactory pollutant removal effects in real water. Overall, this work provides a further and comprehensive cognition about the role of H 2 O 2 in Fe(VI) and Fe(VI)−H 2 O 2 systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Iron-based PAA activation process is a promising advanced oxidation process for water decontamination which depends on Fe(II) as the main reactive site for PAA activation, resulting in various reactive oxidative species (ROSs) generation. For practical application, the impact of water matrix chloride ion (Cl−) on ROSs production and contaminants removal should be carefully considered. In this study, it's found that the introduction of Cl− (0.1–10 mM) could significantly enhance the reaction rate of the rapid stage (k obs1) up to 2.15 times at the initial pH of 4.25 in the Fe(II)/PAA system. Further studies demonstrated that the improved removal capacity of NAP resulted from Cl− induced R-O• generation as indicated by the exposure dose of R-O• increasing from 7.74 × 10−11 M•s to 1.44 × 10−10 M•s, rather than chlorine-containing radicals' generation. DFT calculation results suggested that the formed Fe(II)-Cl− complexes could easily activate PAA to generate more ROSs for NAP removal. Moreover, Fe(II)/PAA treatment can alleviate the biological toxicity of pollutants via both the Escherichia coli test and toxicity assessment. The obtained new knowledge manifested that Cl− can boost ROSs generation and conversion in iron-based PAA systems, providing guidance for the efficient decontamination of chlorine-containing sewage with PAA-based AOPs. [Display omitted] • The presence of Cl− promotes NAP removal in the Fe(II)/PAA system at pH 3.0–9.0. • Cl− accelerates PAA depletion due to the formation of complex ([FeCl(H 2 O) 5 ]+ or [FeCl(OH)(H 2 O) 4 ]). • Cl− induced R-O• generation to become the dominant ROS in Fe(II)/PAA system. • Fe(II)/PAA/Cl− treatment can reduce the biological toxicity of wastewater. [ABSTRACT FROM AUTHOR]

Rationally regulating reaction mechanisms in Fenton-like reactions by tuning the properties of catalysts is of great significance, but still challenging. Herein, we synthesized various active center size-dependent catalysts to realize the switching of reaction mechanisms and pollutant degradation routes in peroxymonosulfate (PMS) activation systems. The results illustrated that the reaction mechanism transformed from radical oxidation (51.64%) to nonradical oxidation (89.92%) with the decrease of active center size from nanoparticle (Co NP -NC) to single atom (Co SA -NC). The evolution of reactive species switched the degradation intermediates and pathway of sulfisoxazole (SIZ). The generation of singlet oxygen (1O 2) in Co SA -NC/PMS tends to selectively attack electron-rich site of SIZ, while reaction between radicals and SIZ prefers non-selective oxidation in Co NP -NC/PMS system. Besides, the toxicity tests indicated that the conversion from non-selective to selective oxidation resulted in lower toxicity of effluent after reaction, which can further reduce environmental risks of effluent. [Display omitted] • Controlled synthesis of cobalt active center sites from nanoparticles to single atoms. • The reaction mechanism transformed from radical oxidation to nonradical oxidation. • The degradation routes of SIZ can be switched in active center size-dependent catalysis. • The toxicity of intermediates can be controlled in active center size-dependent catalysis. [ABSTRACT FROM AUTHOR]

Various MnO x phases and crystals were investigated in peroxymonosulfate (PMS) activation for oxidation of aqueous phenolic pollutants. MnO x with controlled crystal structure (α, β, γ, and amorphous-MnO 2) and redox states (Mn 2 O 3 , and MnO) can induce different oxidative pathways toward organic polymerization against degradation in acidic conditions. Surface MnⅡ (s) and MnⅢ (s) of MnO x tend to bond with PMS to generate confined Mn(Ⅱ, Ⅲ) (s) − (HO)OSO 3 − complexes to initiate a nonradical electron-transfer pathway (ETP). Meanwhile, high-valence MnⅣ (s) in MnO x will directly attack micropollutants and spontaneously be reduced to low-valence states (MnⅡ (s) and MnⅢ (s)) to initiate ETP. Mn 2 O 3 can activate PMS to generate other radical species for mineralization. ETP will selectively initiate one-electron abstraction of phenol molecules into monomer phenoxy radicals and polyphenols on catalyst surface. Thus, manganese crystal structures will govern the surface redox species to induce multiple oxidation pathways toward different polymer products for water decontamination and carbon recycle. [Display omitted] • MnO x catalysts induce organic polymerization/degradation by peroxymonosulfate (PMS). • Crystallinity and valence states of MnO x determine the reaction mechanism and routes. • Low valent Mn species tend to cause electron-transfer pathways (ETPs). • ETPs were responsible for the polymerization while radicals for degradation. [ABSTRACT FROM AUTHOR]

In this study, the catalytic ability and mechanisms involved in activating peroxymonosulfate (PMS) with Mn 3 O 4 and the degradation pathways of bisphenol-AF (BPAF) removal was investigated. SO 4 −• and · OH which were explored by and scavenging tests were the major reactive radicals in the Mn 3 O 4 /PMS system. A simple simulation algorithm was also used to calculate the relative concentrations of SO 4 −• ([SO 4 −•]) and · OH ([ · OH]) which were 8.39 × 10 −15 M and 6.96 × 10 −13 M, respectively. The mechanism for the electron transfer between the Mn (II) and Mn (III) species was discussed. Three degradation pathways of BPAF were determined by the GC/MS and LC/MS technology, including chemical mechanism of oxidation, hydroxylation, electron transfer, polymerization, and ring-cleavage. In addition, the results suggested that the Mn 3 O 4 /PMS system had an efficient total organic carbon (TOC) removal rate and excellent environmental adaptability, the removal rate of TOC being as high as 73.2% in the control condition. Furthermore, the reuse experiments and the comparison on the structural and componential changes of Mn 3 O 4 powder before and after reaction demonstrated that the Mn 3 O 4 catalyst possessed excellent stability and reusability. Finally, a maximum BPAF degradation of approximately 90.0% was achieved on the optimal conditions for 500 mg/L Mn 3 O 4 dosage, 4 mM PMS concentration, 7.0 ± 0.2 initial pH, and 5 mg/L BPAF concentration respectively. And the effect of the coexisting anions and natural environmental water quality were also considered. This study demonstrated the Mn 3 O 4 /PMS system can be considered as a green approach for the removal of environmental reluctant pollutants. Image 1 • A systematic study of using Mn 3 O 4 to activate PMS for BPAF removal was investigated. • The excellent mineralization of the system was confirmed. • The high stability and reusability of the Mn 3 O 4 were distinguished. • Both •OH and SO4−• were responsible for BPAF degradation. • Three degradation pathways of BPAF were proposed. [ABSTRACT FROM AUTHOR]

• The performance of ZVI/peroxymonosulfate could be enhanced with the Cu2+. • Radicals and non-radical species both contributed to the degradation. • The generation of singlet oxygen was investigated in the bimetallic AOPs systems. • Nine main byproducts and degradation pathways were identified. • Accurate toxicity of the byproducts was calculated. Advanced oxidation processes (AOPs) based on the bimetallic system has been demonstrated as a promising way to enhance the degradation of pollutants in the water. In this study, the degradation of Rhodamine B (RhB) in a zero-valent iron (ZVI)/ peroxymonosulfate system with Cu2+ was thoroughly investigated. RhB could be efficiently removed (99.3 %) in the optimal ZVI/PMS/Cu2+ system, while only 58.2 % of RhB could be degraded in the ZVI/PMS system. The influence of reaction parameters on the degradation of RhB was further investigated. Quenching experiments and electron paramagnetic resonance (EPR) tests revealed that various reactive oxygen species could be generated in the ternary system, of which, 1O 2 and O 2 − were identified for the first time. The effect of various anions, NOM and different water matrix were also considered at different concentrations. A variety of byproducts and degradation pathways were identified using HPLC/MS/MS. Finally, the Quantitative Structure Activity Relationship (QSAR) method of Toxicity Estimation Software Tool (TEST) was applied to estimate the toxicity of the byproducts and the results indicated that the overall toxicity of the target was relatively reduced. This study demonstrated the potential for the removal of environmental reluctant pollutants in water via the combined radical and non-radical pathways. [ABSTRACT FROM AUTHOR]