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The degradation of acephate by OH radicals in the environment.

The presence of chloride ions can facilitate the COD removal efficiency due to the involvement of active chlorine species in the electro-oxidation process, but few attentions have been paid to the negative effect of the electro-generated oxychlorides on electro-oxidation performance. In this study, the effects of oxychlorides were investigated as functions of current density and phenol concentration using DSA anodes in terms of the evaluation of the COD removal performance and the biological toxicity. The results show that oxychlorides formed in the electro-oxidation system could result in the over-evaluation of the COD removal performance. Increasing current density (15-50 mA cm

1,2,3-Trimethylbenzene (1,2,3-TMB) is an important volatile organic compound (VOC) present in petroleum wastewater and the atmosphere. This compound can be degraded by OH radicals via abstraction, addition and substitution mechanisms. Results show that the addition mechanism is dominant and H-abstraction is subdominant, while methyl abstraction and substitution mechanisms are negligible in the gas and aqueous phases. Moreover, H-abstraction products undergo further reactions with O

The NO3 radical reactions are deceivingly simple, but they are extremely difficult to describe by quantum chemistry methods due to symmetry breaking.

Introduction: This study aimed to investigate the ganglion cell complex (GCC) parameters in primary angle closure suspects (PACS) and identify the related factors. Methods: A total of 731 subjects, including 289 subjects with PACS and 442 subjects without PACS, underwent RTVue XR OCT. GCC parameters were compared between the two groups. The linear mixed-effects model was performed to evaluate the relationships between the GCC parameters and related factors. Results: Significant differences were found in gender, age, spherical refractive error, height, waist, anterior chamber depth, lens thickness, axial length, superior GCC thickness, ganglion cell complex focal loss volume, ganglion cell complex global loss volume, and ganglion cell complex root mean square between PACS and normal controls. The linear mixed-effects model showed that age ( p = 0.008) and blood glucose ( p = 0.001) were negatively correlated with average GCC thickness in PACS subjects, and PACS ( p = 0.036) and age ( p < 0.001) were the key influencing factors for average GCC thickness. Conclusion: GCC parameters in PACS subjects are different from those in normal controls. Careful explanation should be considered when evaluating changes of GCC parameters in patients with PACD.

Anodic oxidation based on PbO2 anode has been demonstrated as the feasible approach for the decontamination of organic pollutants; however, the performance of this process is hindered by its ordinary electrochemical activity and relatively low stability. In this study, we fabricated an efficient Ti/TiO2-RNTs/Sb-SnO2/PbO2-ND electrode with electrochemically reduced TiO2 nanotubes as the interlayer and nano-diamond as the dopant. As compared with other electrodes, the constructed Ti/TiO2-RNTs/Sb-SnO2/PbO2-ND exhibited higher oxygen evolution overpotential, larger active area and less charge transfer resistance. Thus, the average current efficiency of 30% could be attained at 120 min with TiO2-NTs/Sb-SnO2/PbO2, which was 1.5 times higher in comparison with the typical Ti/Sb-SnO2/PbO2 electrode. It was found that the removal efficiency of COD could be increased from 49% to 69% after 120 min treatment in the presence of 10 mM Cl−1 in the electrolyte. After 6 h of electrolysis, 74% of TOC was removed and 31% and 22% of initial N was transformed into NH4+ and NO3− ions, respectively. And oxalic acid, glyoxylic acid, malonic acid and acetic acid were identified quantitatively as the intermediate products. Finally, it was estimated that the accelerated service life of Ti/TiO2-RNTs/Sb-SnO2/PbO2-ND electrode was approximately three times of Ti/Sb-SnO2/PbO2 electrode. Generally, this study is of great interest for the engineering community to design an efficient electrode material for the wastewater treatment.

As one of the volatile organic compounds (VOCs) in the environment, 1,2,4,5-tetramethylbenzene (1,2,4,5-TeMB) present in oily wastewater, and it can occur substitution, abstraction, and addition reactions with OH radicals in the atmosphere and wastewater. Electrostatic potential (ESP) and average local ionization energy (ALIE) prediction indicate that H atoms from CH

Deliberate addition of mildly oxidative chlorate (ClO

Known organophosphorus pesticides are used widely in agriculture to improve the production of crops. Based on the literature, the degradation of some organophosphorus pesticides was studied theoretically. However, the mechanisms and variation of toxicity during the degradation of mevinphos and monocrotophos are still unclear in the environment, especially in wastewater. In this study, the reaction mechanisms for the degradation of the two representative organophosphorus pesticides (i.e., mevinphos and monocrotophos) in presence of OH radicals in the atmosphere and water are proposed using quantum chemical methods wB97-XD/6-311 + +G(3df,2pd)//wB97-XD/6-311 + +G(d,p). Result shows that the dominant channel is OH-addition to the C atom in CC bond with energy barriers being 15.6 and 14.7 kJ/mol, in the atmosphere and water, respectively, for mevinphos. As for monocrotophos, H-abstraction from NH group via barriers of 8.2 and 10.6 kJ/mol is more feasible in both the atmosphere and water. Moreover, the subsequent reactions of the major products in the atmosphere with NO and O

Background Laser peripheral iridotomy (LPI) is effective in primary angle-closure suspects (PACS); however, predictors for anterior segment alterations after LPI are limited. We aimed to evaluate the anterior segment biometric parameters before and after LPI in PACS using the recently developed, CASIA 2 device of anterior segment optical coherence tomography (AS-OCT). Methods We performed LPI in 52 PACS. Anterior segment parameters, including anterior chamber depth (ACD), anterior chamber width (ACW), anterior chamber volume (ACV), iris curvature (ICURVE), iridotrabecular contact (ITC), lens vault (LV), lens thickness (LT), radius of the lens, angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), and trabecular iris angle (TIA) at different distances (i.e., 500 μm from the sclera spur), were evaluated before and after LPI using CASIA 2. Results Eyes of PACS after LPI had a greater ACV, AOD, ARA, TISA, and TIA, and a lower ITC and ICURVE (all p p = 0.001, p = 0.010, p = 0.004, and p Conclusions We found that LPI widens the anterior chamber angle in the PACS, especially, in the superior quadrant around the iridotomy hole. Eyes with a thicker lens are more likely to experience angle opening because of the LPI.

International audience; The OH-initiated degradation of 2-amino-2-methyl-1-propanol [CH3C(NH2)(CH3)CH2OH, AMP] was investigated in a large atmospheric simulation chamber, employing time-resolved online high-resolution proton-transfer reaction-time-of-flight mass spectrometry (PTR-ToF-MS) and chemical analysis of aerosol online PTR-ToF-MS (CHARON-PTR-ToF-MS) instrumentation, and by theoretical calculations based on M06-2X/aug-cc-pVTZ quantum chemistry results and master equation modeling of the pivotal reaction steps. The quantum chemistry calculations reproduce the experimental rate coefficient of the AMP + OH reaction, aligning k(T) = 5.2 × 10–12 × exp (505/T) cm3 molecule–1 s–1 to the experimental value kexp,300K = 2.8 × 10–11 cm3 molecule–1 s–1. The theoretical calculations predict that the AMP + OH reaction proceeds via hydrogen abstraction from the −CH3 groups (5–10%), −CH2– group, (>70%) and −NH2 group (5–20%), whereas hydrogen abstraction from the −OH group can be disregarded under atmospheric conditions. A detailed mechanism for atmospheric AMP degradation was obtained as part of the theoretical study. The photo-oxidation experiments show 2-amino-2-methylpropanal [CH3C(NH2)(CH3)CHO] as the major gas-phase product and propan-2-imine [(CH3)2C═NH], 2-iminopropanol [(CH3)(CH2OH)C═NH], acetamide [CH3C(O)NH2], formaldehyde (CH2O), and nitramine 2-methyl-2-(nitroamino)-1-propanol [AMPNO2, CH3C(CH3)(NHNO2)CH2OH] as minor primary products; there is no experimental evidence of nitrosamine formation. The branching in the initial H abstraction by OH radicals was derived in analyses of the temporal gas-phase product profiles to be BCH3/BCH2/BNH2 = 6:70:24. Secondary photo-oxidation products and products resulting from particle and surface processing of the primary gas-phase products were also observed and quantified. All the photo-oxidation experiments were accompanied by extensive particle formation that was initiated by the reaction of AMP with nitric acid and that mainly consisted of this salt. Minor amounts of the gas-phase photo-oxidation products, including AMPNO2, were detected in the particles by CHARON-PTR-ToF-MS and GC×GC-NCD. Volatility measurements of laboratory-generated AMP nitrate nanoparticles gave ΔvapH = 80 ± 16 kJ mol–1 and an estimated vapor pressure of (1.3 ± 0.3) × 10–5 Pa at 298 K. The atmospheric chemistry of AMP is evaluated and a validated chemistry model for implementation in dispersion models is presented.

The singlet and triplet potential energy surfaces for the CH2BrO2 + ClO reaction are studied at the CCSD(T)/cc-pVTZ//B3LYP/6-311++G(d,p) level. CH2BrO2 is revealed to react with ClO through two kinds of mechanisms on the triplet potential energy surface (PES), namely, SN2 displacement and H-abstraction, and the production of P3 (CHBrO2 + HOCl) via H-abstraction is the dominant channel. Addition/elimination and SN2 displacement mechanisms exist on the singlet PES and are more complicated. The RRKM calculations of the mechanism and product distribution in the CH2BrO2 + ClO reaction show that the stabilization of IM1 (CH2BrOOOBr) is dominant at T ≤ 600 K, while the pathway of producing P1 (CHBrO + HO2 + Cl) occupies the entire reaction at T > 600 K. The total rate constants are independent of pressure, while the individual rate constants are sensitive to pressure. The lifetime of CH2BrO2 in the presence of ClO is estimated to be 20.27 h. Moreover, time-dependent density functional theory (TDDFT) calculations suggest that IM1 (CH2BrOOOCl), IM2 (CH2BrOOClO) and IM3 (CH2BrOClO2) will photolyze under the sunlight.

It has already been known that oxidative degradation of organochlorine (e.g. chlorophenols) is accompanied by de novo formation of new polychlorinated compounds, however, whether the similar scenario can happen during decomposition of iodine-containing pollutants is completely unknown. Here degradation of two iodinated X-ray contrast media (ICM), iomeprol and iohexol, by sulfate radical generated through Co(II)-mediated activation of peroxymonosulfate (PMS) was investigated. The influencing parameters, such as the initial concentrations of PMS and Co(II), the initial solution pH and natural water constituents were examined. The pseudo-first-order rate constant of iomeprol in the PMS/Co(II) system is more than twice of iohexol, with values of 7.7 × 10−2 and 3.5 × 10−2 min−1, respectively, indicating that iomeprol seems more susceptible to radicals attack than iohexol. The bimolecular rate constants for reaction of sulfate radical (SO4•−) with ICM were determined to be 1.8 × 1010 M−1 s−1 and 7.9 × 109 M−1 s−1 for iomeprol and iohexol, respectively. The low degrees of mineralization and identification of iodinated intermediates of iomeprol and iohexol indicate that the degradation of iomeprol and iohexol in the Co/PMS system were incomplete. A de novo formation of new polyiodinated compounds would not happen because most of released inorganic iodine were ultimately oxidized to iodate (IO3−), rather than the reactive iodinated agents. Based on the identified byproducts and quantum chemical calculation, eight main transformation pathways are proposed for the degradation of iomeprol and iohexol as follows: (a) deiodination; (b) hydrogen abstraction; (c) amide hydrolysis; (d) amino oxidation; (e) hydroxyl substituent; (f) transformed alkyl aromatic amides to aromatic carbamoyl; (g) dehydration; (h) oxidized primary alcohol groups to carboxyl groups.

The degradation reactions of propylamino and dipropylamino radicals in the presence of NO, NO

4-(2-Methoxyethyl) phenol (MEP) is an significant methoxypheolic compound, which has been shown to play an important role in the formation of secondary organic aerosols(SOA). The present work focuses on the gas-phase oxidation mechanism and kinetics of MEP and OH radical by the density functional theory (DFT). Energetically favourable reaction channels and feasible products were identified. The initial reactions of MEP with OH radical have two different channels: OH addition and H abstraction. Subsequent reaction schemes of main intermediates in the presence of O2 and NOx are investigated using quantum chemical methods at M06-2X/6-311++G(3df,2p)//M06-2X/6-311+G(d,p) level. Ketene, Phenyldiketones and nitrophenol compounds are demonstrated to be possible oxidation products. The total rate constant(1.69×10-11 cm3 molecule-1 s-1) and individual rate constant are calculated using the traditional transition state (TST) theory at 298K and 1atm. The lifetime of MEP is estimated to be 16.4 hours, which provides a comprehensive explanation for atmospheric oxidation pathway of MEP and shows MEP would be removed by OH radical in the atmosphere.

Purpose. To compare the effectiveness and safety of carbon dioxide (CO2) laser-assisted deep sclerectomy surgery (CLASS) and trabeculectomy (Trab) for treatment of primary open-angle glaucoma (POAG). Methods. In this retrospective and comparative study, 77 eyes of 62 patients with POAG were studied and divided into the CLASS and Trab groups. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of medications, surgical success rate, and complications were analyzed. Results. The mean follow-up periods were 27.89 ± 2.94 months and 26.11 ± 2.06 months in the CLASS and Trab groups, respectively. 30 eyes (24 patients) underwent CLASS and 47 eyes (38 patients) underwent Trab. The BCVA in the CLASS and Trab groups was recovered to baseline at postoperative 1 week and 1 month, respectively. At last follow-up visits, a remarkable reduction in the IOP and number of medications was observed in both groups, and no significant difference was found in those between the two groups. The complete success rates were 51.7% and 47.7% in postoperative 24 months in the CLASS and Trab groups, respectively ( P > 0.05 ). There were higher rates of delayed anterior chamber formation (21.3%) and thin-wall filtrating blebs (10.6%) in the Trab group. Meanwhile, the peripheral anterior synechiae were only observed in the CLASS group, and the ratio was 30%. Conclusions. CLASS is an effective and safe treatment modality for POAG, with fewer filtering bleb-related complications and quicker visual recovery in the early postoperative stage than trabeculectomy. The efficacy of lowering intraocular pressure was similar for both procedures.

4-(2-Methoxyethyl) phenol (MEP) is an significant methoxypheolic compound, which has been shown to play an important role in the formation of secondary organic aerosols(SOA). The present work focuses on the gas-phase oxidation mechanism and kinetics of MEP and OH radical by the density functional theory (DFT). Energetically favourable reaction channels and feasible products were identified. The initial reactions of MEP with OH radical have two different channels: OH addition and H abstraction. Subsequent reaction schemes of main intermediates in the presence of O2 and NOx are investigated using quantum chemical methods at M06-2X/6-311++G(3df,2p)//M06-2X/6-311+G(d,p) level. Ketene, Phenyldiketones and nitrophenol compounds are demonstrated to be possible oxidation products. The total rate constant(1.69×10-11 cm3 molecule-1 s-1) and individual rate constant are calculated using the traditional transition state (TST) theory at 298K and 1atm. The lifetime of MEP is estimated to be 16.4 hours, which provides a comprehensive explanation for atmospheric oxidation pathway of MEP and shows MEP would be removed by OH radical in the atmosphere.

Glaucoma is the second leading cause of blindness globally characterized by progressive loss of retinal ganglion cells (RGCs) and irreversible visual deficiency. As the most common type of glaucoma, primary open angle glaucoma (POAG) is currently an unmet medical need with limited therapy by lowering intraocular pressure (IOP). However, some patients continue to progress even though their IOP are controlled. Although early diagnosis and prompt treatment are crucial in preventing irreversible visual impairment, there are currently no biomarkers for screening POAG. Metabolomics has the advantages of illustrating the final downstream products of the genome and establishing the closest link to the phenotype. So far, there is no study investigating the metabolomic profiles in both aqueous humor and plasma of POAG patients. Therefore, to explore diagnostic biomarkers, unveil underlying pathophysiology and potential therapeutic strategies, a widely targeted metabolomic approach was applied using ultrahigh-resolution mass spectrometry with C18 liquid chromatography to characterize the metabolomic profiles in both aqueous humor and plasma of 28 POAG patients and 25 controls in our study. Partial least squares-discriminant analysis (PLS-DA) was performed to determine differentially expressed metabolites (DEMs) between POAG and age-matched controls. The area under the receiver operating characteristic curve (AUC) was calculated to assess the prediction accuracy of the DEMs. The correlation of DEMs with the clinical parameters was determined by Pearson correlation, and the metabolic pathways were analyzed using MetaboAnalyst 4.0. PLS-DA significantly separated POAG from controls with 22 DEMs in the aqueous humor and 11 DEMs in the plasma. Additionally, univariate ROC analysis and correlation analysis with clinical parameters revealed cyclic AMP (AUC = 0.87), 2-methylbenzoic acid (AUC = 0.75), 3′-sialyllactose (AUC = 0.73) in the aqueous humor and N-lac-phe (AUC = 0.76) in the plasma as potential biomarkers for POAG. Moreover, the metabolic profiles pointed towards the alteration in the purine metabolism pathway. In conclusion, the study identified potential and novel biomarkers for POAG by crosslinking the metabolomic profiles in aqueous humor and plasma and correlating with the clinical parameters. These findings have important clinical implications given that no biomarkers are currently available for glaucoma in the clinic, and the study provided new insights in exploring diagnostic biomarkers and potential therapeutic strategies of POAG by targeting metabolic pathways.

Purpose To compare the effectiveness and safety of carbon dioxide (CO2) laser-assisted deep sclerectomy surgery (CLASS) and trabeculectomy (Trab) for treatment of primary open-angle glaucoma (POAG). Methods In this retrospective and comparative study, 77 eyes of 62 patients with POAG were studied and divided into the CLASS and Trab groups. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of medications, surgical success rate, and complications were analyzed. Results The mean follow-up periods were 27.89 ± 2.94 months and 26.11 ± 2.06 months in the CLASS and Trab groups, respectively. 30 eyes (24 patients) underwent CLASS and 47 eyes (38 patients) underwent Trab. The BCVA in the CLASS and Trab groups was recovered to baseline at postoperative 1 week and 1 month, respectively. At last follow-up visits, a remarkable reduction in the IOP and number of medications was observed in both groups, and no significant difference was found in those between the two groups. The complete success rates were 51.7% and 47.7% in postoperative 24 months in the CLASS and Trab groups, respectively (P > 0.05). There were higher rates of delayed anterior chamber formation (21.3%) and thin-wall filtrating blebs (10.6%) in the Trab group. Meanwhile, the peripheral anterior synechiae were only observed in the CLASS group, and the ratio was 30%. Conclusions CLASS is an effective and safe treatment modality for POAG, with fewer filtering bleb-related complications and quicker visual recovery in the early postoperative stage than trabeculectomy. The efficacy of lowering intraocular pressure was similar for both procedures.

Over the last decade, new evidence has become increasingly more compelling that commensal microflora profoundly influences the maturation and function of resident immune cells in host physiology. The concept of gut-retina axis is actively being explored. Studies have revealed a critical role of commensal microbes linked with neuronal stress, immune responses, and neurodegeneration in the retina. Microbial dysbiosis changes the blood-retina barrier permeability and modulates T cell-mediated autoimmunity to contribute to the pathogenesis of retinal diseases, such as glaucoma. Heat shock proteins (HSPs), which are evolutionarily conserved, are thought to function both as neuroprotectant and pathogenic antigens of T cells contributing to cell protection and tissue damage, respectively. Activated microglia recruit and interact with T cells during this process. Glaucoma, characterized by the progressive loss of retinal ganglion cells, is the leading cause of irreversible blindness. With nearly 70 million people suffering glaucoma worldwide, which doubles the number of patients with Alzheimer's disease, it represents the most frequent neurodegenerative disease of the central nervous system (CNS). Thus, understanding the mechanism of neurodegeneration in glaucoma and its association with the function of commensal microflora may help unveil the secrets of many neurodegenerative disorders in the CNS and develop novel therapeutic interventions.

Purpose To investigate the morphologic features of crystalline lens in primary angle closure disease (PACD) by the swept-source anterior segment optical coherence tomography. Methods This cross-sectional observational study included 125 consecutive eyes from 125 patients who underwent anterior segment optical coherence tomography (CASIA 2, Tomey, Nagoya, Japan) examination, including 38 eyes of normal controls, 57 eyes of PAC suspects (PACS), and 30 eyes with PAC or PAC glaucoma (PACG). Crystalline lens parameters were compared among the three groups. Spearman correlation analysis and multiple linear regression models were performed to evaluate the relationships between the lens parameters and related factors. Results Significant differences were found for anterior chamber depth, axial length, iridotrabecular contact index, lens vault, lens thickness (all P < 0.001), the anterior radius curvature of lens (normal vs PACS vs PAC/PACG: 9.35 ± 1.29 mm vs 8.40 ± 0.62 mm vs 8.12 ± 0.54 mm; P < 0.001), lens decentration (normal vs PACS vs PAC/PACG: 0.14 ± 0.07 mm vs 0.19 ± 0.09 mm vs 0.22 ± 0.12 mm; P = 0.004), and tilt (normal vs PACS vs PAC/PACG: 4.9 ± 1.0° vs 5.3 ± 1.2° vs 5.8 ± 1.8°; P = 0.033) among the three groups. The multivariate regression analysis found that both iridotrabecular contact index and the stage of the PACD were negatively correlated with the anterior radius curvature of lens, positively correlated with lens thickness and decentration after adjustment for age, sex, and axial length (all P < 0.05). Conclusions Steep anterior curvature and decentration of the crystalline lens may be another anatomic characteristic of eyes with PACD. These findings support that the crystalline lens morphologic features may have great contribution to the development of PACD.

Using quantum chemistry methods, mechanisms and products of the CHBr2O2 + HO2 reaction in the atmosphere were investigated theoretically. Computational result indicates that the dominant product is CHBr2OOH + O2 formed on the triplet potential energy surface (PES). While CBr2O + OH + HO2 produced on the singlet PES is subdominant to the overall reaction under the typical atmospheric condition below 300 K. Due to higher energy barriers surmounted, other products including CBr2O2 + H2O2, CBr2O + HO3H, CH2O + HO3Br, CHBrO + HO3 + Br, and CHBr2OH + O3 make minor contributions to the overall reaction. In the presence of OH radical, CHBr2OOH generates CHBr2O2 and CBr2O2 + H2O subsequently, which enters into new Br-cycle in the atmosphere. The substitution effect of alkyl group and halogens plays negligible roles to the dominant products in the RO2 + HO2 (X = H, CH3, CH2OH, CH2F, CH2Cl, CH2Br, CH2Cl, and CH2Br) reactions in the atmosphere.

The mechanism and kinetic for the reaction of Pyrrole + O(3P) has been investigated using CCSD(T)//M06-2X method with multichannel RRKM-TST calculation. On the triplet surface, four product channels corresponding to α-C-addition, β-C-addition, N-addition and direct H-abstraction have been characterized for the first time. The rate constants and branching ratios for twelve product channels are calculated. It is predicted that the total rate coefficients vary with temperature, and exhibit strong positive temperature dependence. Moreover, the total rate coefficients are independence pressure. On the singlet surface, the atomic oxygen can easily add to the C C double bond or the N atom of Pyrrole forming intermediate s-IM1or s-IM2; both approaches were found to be barrierless. It is indicated that the singlet reaction exhibits a marked difference from the triplet reaction. This calculation is useful to simulate experimental investigations of the Pyrrole + O reaction in the singlet surface.

Mechanisms and channels of the C2H5O2 + ClO reaction in atmosphere were investigated using quantum chemistry method, i.e., CCSD(T)/6-311++G(2d,2p)//B3LYP/6-311++G(d,p) levels of theory. Our result indicates that the title reaction occurs on both the singlet and triplet potential energy surfaces (PESs). Kinetically, C2H5O3Cl and C2H5O + ClOO on the singlet PES were dominant in atmosphere; while other products including CH3CHO2 + HOCl, CH3CHO + HOClO, and CH3CHO + HClO2 make minor contributions to overall reaction due to high barriers and unstable formations. Moreover, time-dependent density functional theory (TDDFT) calculation on the vertical excitation energy implies that C2H5O3Cl will photolyze under the sunlight.

Dimetridazole (DMZ) and ornidazole (ONZ) have been widely used to treat anaerobic and protozoal infections. The residues of DMZ/ONZ persist in the water environment. The mechanisms and kinetics of hydroxyl-initiated oxidation, the primary DMZ/ONZ degradation method, were evaluated by quantum chemical methods.·OH-induced degradation of DMZ and ONZ shared many mechanistic and kinetic characteristics. The most feasible degradation pathway involved forming OH-imidazole adducts and NO2. The OH-imidazole adducts were subsequently degraded into double·OH imidazole intermediates. The rate coefficients for·OH degradation of DMZ and ONZ were 4.32 × 109 M−1 s−1 and 4.42 × 109 M−1 s−1 at 298 K, respectively. The lifetimes of DMZ and ONZ treated with·OH at concentrations of 10−9–10−18 mol L−1 at 298 K were τDMZ = 0.231–2.31 × 108 s and τONZ = 0.226–2.26 × 108 s, respectively. Toxicity assessment showed that the first degradation products of DMZ and ONZ exhibited enhanced aquatic toxicity, whereas most of the secondary degradation products were not harmful to aquatic organisms. Some of transformation products were still developmental toxicant or mutagenicity positive.

The degradation reactions of propylamino and dipropylamino radicals in the presence of NO, NO2 and O2 were investigated at the CCSD(T)/6–311++G (2d, 2p)//B3LYP/6–311++G (d,p) levels of theory. Result indicates that nitrosamines, nitramines, nitroso-oxy compounds and imines can be formed at atmosphere. Time dependent density functional theory (TDDFT) calculation shows that nitrosamines and nitroso-oxy compounds can photolyze under sunlight, while nitramines cannot undergo photolysis in the daytime. Moreover, the ecotoxicity assessment result implies that the degradation of propyl-substituted amines by OH radicals, NO and NO2 will reduce their toxicity to fish, daphnia and green algae in the aquatic environment.

2,2′,4,4′,5,5′-hexabrominated diphenyl ether (BDE-153) and its OH radical addition products are considered potentially harmful to ecological systems. Therefore, the oxidation reactions mechanisms of BDE-153 initiated by OH radical, the reaction kinetics and the ecotoxicity of BDE-153 assessment in the gas and the aqueous phase were investigated using quantum chemical methods. It is more feasible for the OH radical to add at the nonbromine substituted carbon atoms of the aromatic ring in the BDE-153 molecule to create OH addition intermediates. The secondary reactions involving OH addition intermediates in the presence of O2/NO would generate preferred tribromophenol and OH-addition products. Most of the transformation products are still toxic to aquatic organisms. The total and individual rate constants were evaluated by using the KiSThelP program in a suitable temperature range (198–338 K) and a pressure of 1 atm. At 298 K and 1 atm, the total rate constants in atmosphere and wastewater are 2.90 × 10-13 cm3 molecule-1 s−1 and 9.61 × 106 M−1 s−1, and the half-lives are 39.9 days and 72.1–7.21 × 1010 s, respectively. The implicit and explicit solvent models were used to examine the solvent effect on the total reaction. These results clarify the transformation mechanism, atmospheric fate, and ecotoxicity of BDE-153 in advanced oxidation processes. The calculations provided a basis for designing experimental and industrial applications of BDE-153.

TaLHY is an MYB transcription factor (TF) that is upregulated by salicylic acid induction and shows circadian rhythms. However, the study of the upstream regulatory factors is still unclear. In this study, we cloned the promoter sequence of the TaLHY homologous genes, verified the activity of the promoters, and identified important regions that affect promoter activity. Furthermore, we explored a possible upstream regulator of TaLHY, named TaWRKY10, which played a key role in the expression of TaLHY. We found that the three promoters pTaLHYa, pTaLHYb, and pTaLHYd had transcriptional activity in wheat protoplasts. All three promoters have W-Box, which can bind to WRKY TFs. Using virus-induced gene silencing (VIGS), after silencing TaWRKY10, the resistance of ChuanNong 19 (CN19) to stripe rust pathogen strain CYR32 was lost, and the expression level of the TaLHY homologous gene decreased. At the same time, in wheat protoplasts, the transcriptional activity of TaLHY homologous promoters improved after TaWRKY10 overexpression. This indicates that TaWRKY10 is a key gene for wheat immune response to stripe rust, and this gene may bind to TaLHYa, TaLHYb, and TaLHYd promoters to regulate the expression of TaLHY.