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Transforming dissolved organic matter (DOM) is a crucial approach to alleviating the formation of disinfection byproducts (DBPs) in water treatment. Although catalytic ozonation effectively transforms DOM, increases in DBP formation potential are often observed due to the accumulation of aldehydes, ketones, and nitro compound intermediates during DOM transformation. In this study, we propose a novel strategy for the sequential oxidation of DOM, effectively reducing the levels of accumulation of these intermediates. This is achieved through the development of a catalyst with a tailored surface and nanoconfined active sites for catalytic ozonation. The catalyst features a unique confinement structure, wherein Mn-N4 moieties are uniformly anchored on the catalyst surface and within nanopores (5-20 Å). This design enables the degradation of the large molecular weight fraction of DOM on the catalyst surface, while the transformed smaller molecular weight fraction enters the nanopores and undergoes rapid degradation due to the confinement effect. The generation of *Oad as the dominant reactive species is essential for effectively reducing these ozone refractory intermediates. This resulted in over 70% removal of carbonaceous and nitrogenous DBP precursors as well as brominated DBP precursors. This study highlights the importance of the nanoscale sequential reactor design and provides new insights into eliminating DBP precursors by the catalytic ozonation process.
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Desinfección , Ozono , Purificación del Agua , Ozono/química , Catálisis , Purificación del Agua/métodos , Contaminantes Químicos del Agua/químicaRESUMEN
Diabetic encephalopathy (DE) is a severe complication of the central nervous system associated with diabetes. This research aims to investigate the regulatory role of mammalian target of rapamycin (mTOR) on nuclear factor kappa-B (NF-κB) in mice with DE, and the neuroprotective effect and therapeutic mechanisms of luteolin, a natural flavonoid compound with anti-inflammatory, antioxidant, and neuroprotective properties. The results indicated that treatment with luteolin improved the degree of cognitive impairment in mice with DE. It also decreased the levels of p-mTOR, p-NF-κB and histone deacetylase 2 (HDAC2) and increased the expression of brain-derived neurotrophic factor (BDNF) and synaptic-related proteins. Furthermore, protein-protein interaction (PPI) and the Gene Ontology (GO) analysis revealed that luteolin was involved in the regulatory network of HDAC2 expression through the mTOR/NF-κB signaling cascade. Our bioinformatics and molecular docking results indicated that luteolin may also directly target HDAC2, as an HDAC2 inhibitors, to alleviate DE, complementing mTOR/NF-κB signaling inhibition. Analysis of luteolin's target genes and their interactions suggested effect on HDAC2 and cognition. In conclusion, HDAC2 and tau hyperphosphorylation are regulated by the mTOR/NF-κB signaling cascade in DE, and luteolin is found to reverse these effects, demonstrating its protective role in DE.
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The photoexcited dissolved organic matter (DOM) could produce reactive intermediates, affecting chemical oxidant transformation in UV based advanced oxidation processes (AOPs). This study confirmed the critical role of triplet state DOM (3DOM*), generated from DOM photoexcitation, in the transformation of monochloramine (NH2Cl), a commonly used chemical oxidant and disinfectant in water treatment. NH2Cl (42.25 µM, as Cl2) was decayed by 17.4-73.4 % within 60 min, primarily due to 3DOM* , in DOM (2-30 mgC L-1) solutions irradiated by 365 nm, where NH2Cl has no absorption. The second-order quenching rate constants of triplet state model photosensitizers by NH2Cl were determined to be 0.95(± 0.04)-4.49(± 0.04)× 108 M-1 s-1 by using laser flash photolysis. As a reductant, 3DOM* reacted with NH2Cl through one-transfer mechanism, leading to amino radical (NH2â¢) generation, which then transferred to ammonia (NH4+, pKa 9.25) through H-abstraction by the phenolic moieties in DOM. Additionally, the intermediate product of 3DOM* oxidized by NH2Cl or those triplet state quinones can hydrolyze to form phenolic moieties, elevating NH4+ yield to higher than 99% upon 365 nm irradiation. These findings suggest that the widespread DOM can be applied to convert NH2Cl via 3DOM* with minimal toxic risks.
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Excited triplet states of wastewater effluent organic matter (3EfOM*) are known as important photo-oxidants in the degradation of extracellular antibiotic resistance genes (eArGs) in sunlit waters. In this work, we further found that 3EfOM* showed highly selective reactivity toward 2'-deoxyguanosine (dG) sites within eArGs in irradiated EfOM solutions at pH 7.0, while it showed no photosensitizing capacity toward 2'-deoxyadenosine, 2'-deoxythymidine, and 2'-deoxycytidine (the basic structures of eArGs). The 3EfOM* contributed to the photooxidation of dG primarily via one-electron transfer mechanism, with second-order reaction rate constants of (1.58-1.74) × 108 M-1 s-1, forming the oxidation intermediates of dG (dG(-H)â¢). The formed dG(-H)⢠could play a significant role in hole hopping and damage throughout eArGs. Using the four deoxynucleosides as probes, the upper limit for the reduction potential of 3EfOM* is estimated to be between 1.47 and 1.94 VNHE. Compared to EfOM, the role of the triplet state of terrestrially natural organic matter (3NOM*) in dG photooxidation was minor (â¼15%) mainly due to the rapid reverse reactions of dG(-H)⢠by the antioxidant moieties of NOM. This study advances our understanding of the difference in the photosensitizing capacity and electron donating capacity between NOM and EfOM and the photodegradation mechanism of eArGs induced by 3EfOM*.
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Aguas Residuales , Contaminantes Químicos del Agua , Fotólisis , Antibacterianos , Oxidantes , Farmacorresistencia MicrobianaRESUMEN
Advanced oxidation processes (AOPs) often employ strong oxidizing inorganic radicals (e.g., hydroxyl and sulfate radicals) to oxidize contaminants in water treatment. However, the water matrix could scavenge the strong oxidizing radicals, significantly deteriorating the treatment efficiency. Here, we report a periodate/catechol process in which reactive quinone species (RQS) including the o-semiquinone radical (o-SQâ¢-) and o-benzoquinone (o-Q) were dominant to effectively degrade anilines within 60 s. The second-order reaction rate constants of o-SQâ¢- and o-Q with aniline were determined to be 1.0 × 108 and 4.0 × 103 M-1 s-1, respectively, at pH 7.0, which accounted for 21% and 79% of the degradation of aniline with a periodate-to-catechol molar ratio of 1:1. The major byproducts were generated via addition or polymerization. The RQS-based process exhibited excellent anti-interference performance in the degradation of aniline-containing contaminants in real water samples in the presence of diverse inorganic ions and organics. Subsequently, we extended the RQS-based process by employing tea extract and dissolved organic matter as catechol replacements as well as metal ions [e.g., Fe(III) or Cu(II)] as periodate replacements, which also exhibited good performance in aniline degradation. This study provides a novel strategy to develop RQS-based AOPs for the highly selective degradation of aniline-containing emerging contaminants.
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Compuestos Férricos , Ácido Peryódico , Contaminantes Químicos del Agua , Peróxido de Hidrógeno , Oxidación-Reducción , Benzoquinonas , Compuestos de Anilina , Catecoles , Contaminantes Químicos del Agua/análisisRESUMEN
Triplet state dissolved organic matter (3DOM*) plays a significant role in inducing oxidant decay and radical generation in light-based advanced oxidation processes. However, the effects of pH still need investigation. This work quantitatively analyzed the pH-dependent free available chlorine (FAC) decay and radical formation (i.e., HO⢠and Clâ¢) induced by 3DOM* or triplet state photosensitizer (3PS*). Upon UV irradiation at 254 nm, the decay rate of FAC by 3DOM* or 3PS* was the highest at neutral pH, while those by dark reaction of DOM and the direct photolysis of FAC were the highest at acidic conditions. This is attributed to the variation of FAC species, 3DOM* or 3PS* formation, and the reaction rate constants of FAC with 3DOM* or 3PS* at pH 5.0-10.0. 3DOM* and 3PS* formed increasingly with pH varying from 5.0 to 10.0, while their reactivity with FAC decreased due to the speciation from HOCl to OCl-. Radical formation (i.e., HO⢠and Clâ¢) from FAC reaction with 3DOM* or 3PS* occurred at all the testing pH range (5.0-10.0). This work highlighted the pH-dependent role of 3DOM* in oxidant decay and radical formation in treating DOM containing waters through oxidant photolysis. ENVIRONMENTAL IMPLICATIONS: Triplet state dissolved organic matter (3DOM*) plays a significant role in inducing oxidant decay and radical generation in light-based AOPs. This study revealed the effects of pH in 3DOM* induced free available chlorine (FAC) decay and radical formation (i.e., HO⢠and Clâ¢). With DOM at 3 mgC L-1, FAC decayed fastest under neutral conditions and radical formation (i.e., HO⢠and Clâ¢) was enhanced at 5.0-10.0 due to 3DOM* reaction with FAC. These results highlighted the pH-dependent role of 3DOM* in oxidant transformation and radical formation in treating DOM containing waters by AOPs based on oxidant photolysis.
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The low intrinsic thermal conduction and high dielectric properties of epoxy resins have significantly limited their applications in electrical and electronic devices with high integration, high frequency, high power, and miniaturization. Herein, a liquid crystalline epoxy (LCE) monomer with a biphenyl mesogenic unit was first synthesized through an efficient one-step reaction. Subsequently, bisphenol AF (BPAF) containing low-polarizable -CF3 groups and 4,4'-diaminodiphenylmethane (DDM) were applied to cure the LCE and commercial diglycidyl ether of bisphenol A-type epoxy (E-51), respectively, to afford four kinds of epoxy resins with various intrinsic thermal conductivity and dielectricity values. Owing to the dual effect of microscopically stacking of mesogens and the contribution of fluorine to the formation of liquid crystallinity, ordered microstructures of the nematic liquid crystal phase were formed within the cross-linking network of LCE as confirmed by polarized optical microscopy and X-ray diffraction. Consequently, phonon scattering was suppressed, and the intrinsic thermal conductivity was improved considerably to 0.38 W/(m·K), nearly twice as high as that of E-51 cured with DDM (0.20 W/(m·K)). Additionally, the ordered microstructure and ultralow polar -CF3 groups within LCE cured with BPAF enabled the epoxy resin to exhibit a remarkably lower and stable dielectric constant (ε) and dielectric loss tangent (tanâ¯Î´) over both low and high frequencies compared to E-51 cured with DDM. The ε decreased from 3.40 to 2.72 while the tanâ¯Î´ decreased from 0.044 to 0.038 at 10 GHz. This work presents a scalable and facile strategy for breaking the bottleneck of making epoxy resins simultaneously with high inherent thermal conduction and low dielectric performance.
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Photolysis of free chlorine is an increasingly recognized approach for effectively inactivating microorganisms and eliminating trace organic contaminants. However, the impact of dissolved organic matter (DOM), which is ubiquitous in engineered water systems, on free chlorine photolysis is not yet well understood. In this study, triplet state DOM (3DOM*) was found to cause the decay of free chlorine for the first time. By using laser flash photolysis, the scavenging rate constants of triplet state model photosensitizers by free chlorine at pH 7.0 were determined to be in the range of (0.26-3.33) × 109 M-1 s-1. 3DOM*, acting as a reductant, reacted with free chlorine at an estimated reaction rate constant of 1.22(±0.22) × 109 M-1 s-1 at pH 7.0. This study revealed an overlooked pathway of free chlorine decay during UV irradiation in the presence of DOM. Besides the DOM's light screening ability and scavenging of radicals or free chlorine, 3DOM* played an important role in the decay of free chlorine. This reaction pathway accounted for a significant proportion of the decay of free chlorine, ranging from 23 to 45%, even when DOM concentrations were below 3 mgC L-1 and a free chlorine dose of 70 µM was present during UV irradiation at 254 nm. The generation of HO⢠and Cl⢠from the oxidation of 3DOM* by free chlorine was confirmed by electron paramagnetic resonance and quantified by chemical probes. By inputting the newly observed pathway in the kinetics model, the decay of free chlorine in UV254-irradiated DOM solution can be well predicted.
Asunto(s)
Cloro , Contaminantes Químicos del Agua , Materia Orgánica Disuelta , Rayos Ultravioleta , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis , FotólisisRESUMEN
As a revolutionary biological science and technology, synthetic biology has already spread its influence from natural sciences to humanities and social sciences by introducing biosafety, biosecurity, and ethical issues to society. The current study aims to elaborate the intellectual bases and research front of the synthetic biology field in the sphere of philosophy, ethics, and social sciences, with knowledge mapping and bibliometric methods. The literature records from the Social Sciences Citation Index and Arts & Humanities Citation Index in the Web of Science Core Collection from 1982 to 2021 were collected and analyzed to illustrate the intellectual structure of philosophical, ethical, and social research of synthetic biology. This study profiled the hotspots of research focus on its governance, philosophical and ethical concerns, and relevant technologies. This study offers clues and enlightenment for the stakeholders and researchers to follow the progress of this emerging discipline and technology and to understand the cutting-edge ideas and future form of this field, which takes on greater significance in the post-COVID-19 era.
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Wastewater effluent is a major source of extracellular antibiotic resistance genes (eArGs) in the aquatic environment, a threat to human health and biosecurity. However, little is known about the extent to which organic matter in the wastewater effluent (EfOM) might contribute to photosensitized oxidation of eArGs. Triplet states of EfOM were found to dominate the degradation of eArGs (accounting for up to 85%). Photo-oxidation proceeded mainly via proton-coupled electron transfer reactions. They broke plasmid strands and damaged bases. O2â¢- was also involved, and it coupled with the reactions' intermediate radicals of eArGs. The second-order reaction rates of blaTEM-1 and tet-A segments (209-216 bps) with the triplet state of 4-carboxybenzophenone were calculated to be (2.61-2.75) × 108 M-1 s-1. Besides as photosensitizers, the antioxidant moieties in EfOM also acted as quenchers to revert intermediate radicals back to their original forms, reducing the rate of photodegradation. However, the terrestrial origin natural organic matter was unable to photosensitize because it formed less triplets, especially high-energy triplets, so its inhibitory effects predominated. This study advances our understanding of the role of EfOM in the photo-oxidation of eArGs and the difference between EfOM and terrestrial-origin natural organic matter.
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Aguas Residuales , Contaminantes Químicos del Agua , Humanos , Antibacterianos/farmacología , Oxidación-Reducción , Fotoquímica , Farmacorresistencia Microbiana/genéticaRESUMEN
To activate persulfate to generate reactive species such as sulfate radical (SO4â¢-) for micropollutants abatement, external energy or chemicals are often needed. In this study, a novel SO4â¢- formation pathway was reported during the oxidation of neonicotinoids by peroxydisulfate (S2O82-, PDS) without any other chemical additions. Thiamethoxam (TMX) was used as a representative neonicotinoid and SO4â¢- was the dominant specie contributing to its degradation during PDS oxidation at neutral pH. TMX anion radical (TMXâ¢-) was found to activate PDS to generate SO4â¢- with the second-order reaction rate constant determined to be (1.44 ± 0.47)× 106 M-1s-1 at pH 7.0 by using laser flash photolysis. TMXâ¢- was generated from the TMX reactions with superoxide radical (O2â¢-), which was formed from the hydrolysis of PDS. This indirect PDS activation pathway via anion radicals was also applicable to other neonicotinoids. The formation rates of SO4â¢- were found to negatively linearly correlated with Egap (LUMO-HOMO). The DFT calculations indicated the energy barrier of anion radicals to activate PDS was greatly reduced compared to the parent neonicotinoids. The pathway of anion radicals' activation of PDS to form SO4â¢- improved the understanding of PDS oxidation chemistry and provided some guidance to enhance oxidation efficiency in field applications.
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In bio-medical mobile workstations, e.g., the prevention of epidemic viruses/bacteria, outdoor field medical treatment and bio-chemical pollution monitoring, the conventional bench-top microscopic imaging equipment is limited. The comprehensive multi-mode (bright/dark field imaging, fluorescence excitation imaging, polarized light imaging, and differential interference microscopy imaging, etc.) biomedical microscopy imaging systems are generally large in size and expensive. They also require professional operation, which means high labor-cost, money-cost and time-cost. These characteristics prevent them from being applied in bio-medical mobile workstations. The bio-medical mobile workstations need microscopy systems which are inexpensive and able to handle fast, timely and large-scale deployment. The development of lightweight, low-cost and portable microscopic imaging devices can meet these demands. Presently, for the increasing needs of point-of-care-test and tele-diagnosis, high-performance computational portable microscopes are widely developed. Bluetooth modules, WLAN modules and 3G/4G/5G modules generally feature very small sizes and low prices. And industrial imaging lens, microscopy objective lens, and CMOS/CCD photoelectric image sensors are also available in small sizes and at low prices. Here we review and discuss these typical computational, portable and low-cost microscopes by refined specifications and schematics, from the aspect of optics, electronic, algorithms principle and typical bio-medical applications.
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Lentes , Microscopía , Microscopía/métodos , Sistemas de Atención de Punto , Algoritmos , Microscopía de InterferenciaRESUMEN
The triplet states of dissolved organic matter (3DOM*) have been well known to oxidize various organic contaminants, but evidence of their reducing properties are largely scarce. In this work, chlorine dioxide (ClO2) as a single-electron oxidant was used as a probe to evaluate the reduction property of 3DOM*. The reduction of ClO2 to chlorite was observed in the solutions of model photosensitizers (i.e., 4-carboxybenzophenone, benzophenone, acetophenone, 3-methoxyacetophenone, naphthalene, and xanthone) during UV irradiation with the presence of ClO2, though they are resistant to ClO2 oxidation in the dark. The reducing property of the triplet states of photosensitizers was verified and their second-order reaction rate constants with ClO2 were determined to be in the range of 1.45(± 0.03)× 109 - 2.18(± 0.06) × 109 M-1 s-1 at pH 7.0. The quenching tests excluded the role of other reactive species (e.g., HOâ¢, O(3P), Clâ¢, ClO⢠and HOCl/OCl-, O2â¢- and eaq-) in ClO2 reduction to chlorite when using model photosensitizers and DOM isolates. Chlorite formation was 48.1-90.4% and 4812.8-7721.8% higher during UV irradiation with the presence of ClO2 and DOM than those without UV irradiation or without DOM present, respectively. The enhancement was attributed to the enhanced electron donating capacity (chlorite precursors) of DOM upon UV irradiation and also to 3DOM* acting as an electron donor reducing ClO2 to chlorite. This study highlighted the important role of 3DOM* as a reductant.
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Compuestos de Cloro , Purificación del Agua , Xantonas , Fármacos Fotosensibilizantes , Sustancias Reductoras , Compuestos de Cloro/química , Óxidos/química , Oxidación-Reducción , Oxidantes , Benzofenonas , Naftalenos , Acetofenonas , Cloro/químicaRESUMEN
A novel fluorescent probe TSOC (thiazole salicylaldehyde oxazole chlorinated) was synthesized based on benzothiazole conjugated olefinic bonds with salicylicaldehyde unit as fluorophore and a phenyl oxazole unit as bonding unit. The probe could reversibly detect of Cu2+and S2-over other common ions with longer emission and large stokes shift in an aqueous solution at pH 7.3 (DMSO-Hepes, v/v, 5:1, 10 mM). The bonding mechanism was supported through the titration experiment of fluorescence and absorption spectroscopy,1H-NMR titration, HR-MS and DFT calculations. Moreover, the probe further exhibited good cell permeability and were successfully used to visualize Cu2+and S2-in living cells.
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Colorantes Fluorescentes , Oxazoles , Teoría Funcional de la Densidad , Colorantes Fluorescentes/química , Iones , Espectrometría de FluorescenciaRESUMEN
This study systematically revealed the feasibility of the sequential ClO2-UV/chlorine process for micropollutant removal and disinfection byproduct (DBP) control. The results demonstrated that the sequential ClO2-UV/chlorine process was effective for the removal of 12 micropollutants. ClO2 pre-treatment reduced the formation of disinfect byproducts (DBPs) in the UV/chlorine process. Compared to the UV/chlorine process, ClO2 pre-treatment (1.0 mg L-1) decreased the formation of the 6 DBPs by 25.1-72.2%; and decreased the formation potential of the 6 DBPs by 13.9-51.8%. Moreover, ClO2 pre-treatment reduced the concentration of total organic chlorine by 19.8%. ClO2 pre-treatment affected the UV/chlorine process in different ways. Firstly, ClO2 pre-treatment generated chlorite, which dominantly served as a scavenger of chlorine radical (Cl) and hydroxyl radical (HO). Secondly, ClO2 pre-treatment decreased the reactivity of natural organic matter (NOM) towards radicals. Finally, ClO2 pre-treatment altered the properties of NOM, in terms of reducing the electron-donating capacity and aromaticity of NOM (SUVA254), and slightly reducing the average molecular weight of NOM. Overall, ClO2 pre-treatment effectively controlled the formation of DBPs in the UV/chlorine process. This study confirmed the sequential ClO2-UV/chlorine process was an alternative strategy to balancing the micropollutant removal and DBP control.
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Contaminantes Químicos del Agua , Purificación del Agua , Cloro , Desinfección , Halogenación , Radical Hidroxilo , Contaminantes Químicos del Agua/análisisRESUMEN
Photolysis of ClO2 by UVC radiation occurs in several drinking water treatment scenarios (e.g., pre-oxidation by ClO2 with post-UVC disinfection or a multi-barrier disinfection system comprising ClO2 and UVC disinfection in sequence). However, whether micropollutants are degraded and undesired byproducts are formed during the co-exposure of ClO2 and UVC radiation remain unclear. This study demonstrated that four micropollutants (trimethoprim, iopromide, caffeine, and ciprofloxacin) were degraded by 14.4-100.0% during the co-exposure of ClO2 and UVC radiation in the synthetic drinking water under the environmentally relevant conditions (UV dose of 207 mJ cm-2, ClO2 dose of 1.35 mg L-1, and pH of 7.0). Trimethoprim and iopromide were predominantly degraded by ClO2 oxidation and direct UVC photolysis, respectively. Caffeine and ciprofloxacin were predominantly degraded by the radicals (HO⢠and Clâ¢) and the in-situ formed free chlorine from ClO2 photolysis, respectively. The yields of total organic chlorine (12.5 µg L-1 from 1.0 mg C L-1 of NOM) and chlorate (0.14 mg L-1 From 1.35 mg L-1 of ClO2) during the co-exposure were low. However, the yield of chlorite was high (0.76 mg L-1 from 1.35 mg L-1 of ClO2), which requires attention and control.
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Compuestos de Cloro , Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Cloro , Desinfección , Oxidación-Reducción , Óxidos , Contaminantes Químicos del Agua/análisisRESUMEN
Polychoro-1,3-butadienes (CBDs) were widely found in aqueous environment and resistant to conventional water treatment. In this study, the abatement of CBDs during UV/chlorine treatment was investigated. In comparison to UV irradiation alone, free chlorine addition brought benefits for the reduction of tetra-CBDs (TCBDs), but to lesser extent for penta-CBDs (PCBDs), and virtually no benefit for hexa-CBD (HCBD). At a UV dose of 128 mJ cm-2 and a chlorine dose of 10 mg L-1, about 71.7-97.8% CBDs were degraded by UV/chlorine treatment within 10 min. UV irradiation contributed 32.8%-97.6%, HO⢠contributed 2.6%-14.4%, and reactive chlorine species (RCS) contributed less than 0.5%-42.3% to CBDs degradation. The percentages of RCS contribution generally followed the order of TCBDs (except (Z,Z)-1,2,3,4-TCBD) > PCBDs > HCBD. The chlorine oxide radical (ClOâ¢) was the dominant RCS contributing to the degradation of CBDs. The second-order reaction rate constants of ClO⢠with CBDs ( [Formula: see text] ) were at â¼ 107 M-1s-1 except (Z,Z)-1,2,3,4-TCBD and HCBD (<106 M-1s-1). [Formula: see text] generally decreased with increasing numbers of chlorine atoms and was also affected by the positions of chlorine atoms in CBDs. A distinct reaction pathway of ClOâ¢, with (Z)-1,1,2,3,4-PCBD as a representative CBD, was proposed. Photoisomers of CBDs from Z or E configuration were observed at lower concentrations in UV/chlorine treatment than under UV irradiation alone due to the radical-involved oxidation, but more organic acids including oxalic acid were observed. In a natural water sample, UV/chlorine treatment also exhibited a good performance in abatement of TCBDs and PCBDs, but not in abatement of HCBD.
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Contaminantes Químicos del Agua/análisis , Purificación del Agua , Butadienos , Cloro , Cinética , Oxidación-Reducción , Rayos UltravioletaRESUMEN
Hexachloro-1,3-butadiene (HCBD) is a persistent organic pollutant listed in Annex A and C of the Stockholm Convention. This review summarized the sources, occurrence, toxicity, and transformation of HCBD in the environment. HCBD had no natural sources, and anthropogenic sources made it frequently detected in environmental medium, generally at µg L- 1 and µg kg- 1 in water and soil (or organism) samples, respectively. HCBD posed reproductive, genetic, and potentially carcinogenic toxicity to organisms, threatening human health and the ecosystem. Upon biodegradation, photodegradation and physicochemical degradation processes, HCBD can be degraded to a different extent. Nevertheless, further studies should be focused on the potential emission sources and the impact of HCBD on human health and the environment. Additionally, exploring removal technologies based on advanced oxidation and reduction are recommended.
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Butadienos , Contaminantes Químicos del Agua , Purificación del Agua/métodos , Animales , Biodegradación Ambiental , Biotransformación , Butadienos/análisis , Butadienos/metabolismo , Butadienos/toxicidad , Ecosistema , Agua Dulce/química , Humanos , Oxidación-Reducción , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidadRESUMEN
Scientific research cooperation has become a mainstream trend of social development. It can promote resource sharing, help group members complement each other's advantages, and improve scientific research efficiency. With the deepening of scientific research cooperation, there have also been problems such as the uneven strength of partners, gender discrimination, and group exclusionary behavior. People often explore the causes of these problems in terms of the process of scientific research cooperation, but doing so fails to solve the substantive problems effectively. We thus seek to trace the psychology of people participating in scientific research cooperation from the perspective of evolutionary psychology so as to analyze the root causes of scientific research cooperation problems. This paper first discusses the importance of scientific research cooperation, then enumerates common problems in scientific research cooperation, analyzes them from the perspective of evolutionary psychology, and proposes solutions to these problems from the perspective of regulating people's psychology. This article illustrates how the many perspectives and theories of evolutionary psychology can solve problems in other disciplines and fields, and indeed that all human social activities can be explained by evolutionary psychology, which opens up a broader field of research for evolutionary psychology.
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In this paper, a new method, which is based on reconstructing the original intensity distribution of a laser with images captured by a charge-coupled device (CCD) in two orthogonal directions, is proposed for suppressing the influence of CCD vertical blooming on the measurement of the laser beam quality factor (M2). A simplified theoretical model for the distribution of CCD blooming is also proposed. With the proposed method and model, the influence of CCD vertical blooming on the measurement of M2 is simulated. The experimental results demonstrate that the new method can be an effective means to measure the M2 of a near-infrared laser with a silicon CCD camera. The proposed method can be applied to a beam quality analyzer in order to suppress the influence of blooming on the measurement of M2.