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Fenton-conditioning is commonly used to improve dewatering ability for municipal biological sludge, however, its application in industries is scarce. In this study, biochar (FT-BC) was successfully synthesized from a Fenton-conditioned landfill leachate biological sludge under oxygen-limited. As compared to the corresponding blank and poly ferric-pretreated biochars (BC and PF-BC), moderate Fenton conditioning of the sludge could enable good removal performance for Cr (â ¥) by FT-BC. It was found that the oxygen central free radicals (OCFRs) on the biochar surface was intensively promoted due to Fenton electrophilic addition of ·OH onto the oxygen-containing functional groups in biomass. The amounts of OCFRs correlated positively well with the removal efficiency, indicating these persistent free radicals (PFRs)would mainly responsible for the reductive immobilization of Cr(VI)on the FT-BC surface. This study is expected to provide a new method for reclamation of industrial biological sludges with poor agglomeration by introducing simple Fenton pre-conditioning.
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Carvão Vegetal , Esgotos , Carvão Vegetal/química , Esgotos/química , Radicais Livres/química , Cromo/química , Poluentes Químicos da Água/química , Ferro/química , Oxigênio/química , Peróxido de Hidrogênio/químicaRESUMO
LSD1 has become an appealing target for the development of new pharmacologic agents to treat cardiovascular diseases, including heart failure. Herein, we reported the design, synthesis, and structure-activity relationship of a series of TCP-based derivatives targeting LSD1. Docking studies were employed to successfully elucidate the SAR. Particularly, compound 7d, characterized by low toxicity, demonstrated a high affinity for LSD1 at molecular and cellular levels. It also displayed favorable pharmacokinetic properties for oral dosing (e.g., F = 77.61%), effectively alleviating Ang II-induced NRCFs activation in vitro and reducing pathological myocardial remodeling in TAC-induced cardiac remodeling and heart failure in vivo. Additionally, mechanism studies revealed that suppression of myocardial dysfunction by compound 7d is related to LSD1 inhibition-induced TGFß signaling pathway repressing. In summary, the current report presents compound 7d as a potent LSD1 inhibitor with the potential for further development as a therapeutic agent for pressure overload-related heart failure.
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Desenho de Fármacos , Insuficiência Cardíaca , Histona Desmetilases , Simulação de Acoplamento Molecular , Histona Desmetilases/antagonistas & inibidores , Histona Desmetilases/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Animais , Relação Estrutura-Atividade , Humanos , Administração Oral , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/uso terapêutico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/administração & dosagem , Masculino , Camundongos , Ratos , Camundongos Endogâmicos C57BLRESUMO
Electrochemical advanced oxidation processes (EAOPs) based on natural air diffusion electrode (NADE) promise efficient and affordable advanced oxidation water purification, but the sustainable operation of such reaction systems remains challenging due to severe cathode electrowetting. Herein, a novel floating cathode (FC) composed of a stable hydrophobic three-phase interface was established by designing a flexible catalytic layer of FC. This innovative electrode configuration could effectively prolong the service life of the cathode by mitigating the interference of H2 bubbles from the hydrogen evolution reaction (HER), and the H2O2 production rate reached 37.59 mg h-1·cm-2 and realize a long-term stable operation for 10 h. Additionally, an FC/carbon felt (CF) dual-cathode electro-Fenton system was constructed for in situ sulfamethoxazole (SMX) degradation. Efficient H2O2 production on FC and Fe(III) reduction on CF were synchronously achieved, attaining excellent degradation efficiency for both SMX (ca. 100%) with 2.5 mg L-1 of Fe(â ¡) injection. For real wastewater, the COD removal of the FC/CF dual-cathode electro-Fenton system was stabilized at exceeding 75%. The practical application potential of the FC/CF dual-cathode electro-Fenton system was also demonstrated for the treatment of actual landfill leachate in continuous flow mode. This work provides a valuable path for constructing a sustainable dual-cathode electro-Fenton system for actual wastewater treatment.
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Eletrodos , Peróxido de Hidrogênio , Ferro , Oxirredução , Águas Residuárias , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/química , Águas Residuárias/química , Ferro/química , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos , Descontaminação/métodos , Técnicas Eletroquímicas/métodosRESUMO
Visible-light-promoted thiolation of benzyl chlorides with thiosulfonates is disclosed via an electron donor-acceptor complex strategy. In addition to efficiently delivering a series of arylbenzylsulfide compounds, versatile thioglycosides were also successfully constructed by applying the metal- and photocatalyst-free protocol. Preliminary mechanistic studies suggest that a radical-radical coupling process was involved in this transformation.
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Chirality constitutes an inherent attribute of nature. The catalytic asymmetric synthesis of molecules with central, axial, and helical chirality is a topic of intense interest and is becoming a mature field of research. However, due to the difficulty in synthesis and the lack of a prototype, less attention has been given to planar chirality arising from the destruction of symmetry on a single planar ring. Herein, we report the catalytic asymmetric synthesis of planar-chiral dianthranilides, a unique class of tub-shaped eight-membered cyclic dilactams. This protocol is enabled by cinchona alkaloid-catalyzed (dynamic) kinetic resolution. Under mild conditions, various C2- or C1-symmetric planar-chiral dianthranilides have been readily prepared in high yields with excellent enantioselectivity. These dianthranilides can serve as an addition to the family of planar-chiral molecules. Its synthetic value has been demonstrated by kinetic resolution of racemic amines via acyl transfer, enantiodivergent synthesis of the natural product eupolyphagin, and preliminary antitumor activity studies.
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BACKGROUND: This study aimed to investigate the differences in the microbiota composition of serum exosomes from patients with acute and chronic cholecystitis. METHOD: Exosomes were isolated from the serum of cholecystitis patients through centrifugation and identified and characterized using transmission electron microscopy and nano-flow cytometry. Microbiota analysis was performed using 16S rRNA sequencing. RESULTS: Compared to patients with chronic cholecystitis, those with acute cholecystitis exhibited lower richness and diversity. Beta diversity analysis revealed significant differences in the microbiota composition between patients with acute and chronic cholecystitis. The relative abundance of Proteobacteria was significantly higher in exosomes from patients with acute cholecystitis, whereas Actinobacteria, Bacteroidetes, and Firmicutes were significantly more abundant in exosomes from patients with chronic cholecystitis. Furthermore, functional predictions of microbial communities using Tax4Fun analysis revealed significant differences in metabolic pathways such as amino acid metabolism, carbohydrate metabolism, and membrane transport between the two patient groups. CONCLUSIONS: This study confirmed the differences in the microbiota composition within serum exosomes of patients with acute and chronic cholecystitis. Serum exosomes could serve as diagnostic indicators for distinguishing acute and chronic cholecystitis.
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Colecistite Aguda , Colecistite , Exossomos , Microbioma Gastrointestinal , Microbiota , Humanos , RNA Ribossômico 16S/genética , Microbioma Gastrointestinal/genética , Fezes/microbiologia , Microbiota/genéticaRESUMO
Polymerization-driven removal of pollutants in advanced oxidation processes (AOPs) offers a sustainable way for the simultaneous achievement of contamination abatement and resource recovery, supporting a low-carbon water purification approach. However, regulating such a process remains a great challenge due to the insufficient microscopic understanding of electronic structure-dependent reaction mechanisms. Herein, this work probes the origin of catalytic pollutant polymerization using a series of transition metal (Cu, Ni, Co, and Fe) single-atom catalysts and identifies the d-band center of active site as the key driver for polymerization transfer of pollutants. The high-valent metal-oxo species, produced via peroxymonosulfate activation, are found to trigger the pollutant removal via polymerization transfer. Phenoxyl radicals, identified by the innovative spin-trapping and quenching approaches, act as the key intermediate in the polymerization reactions. More importantly, the oxidation capacity of high-valent metal-oxo species can be facilely tuned by regulating their binding strength for peroxymonosulfate through d-band center modulation. A 100% polymerization transfer ratio is achieved by lowering the d-band center. This work presents a paradigm to dynamically modulate the electronic structure of high-valent metal-oxo species and optimize pollutant removal from wastewater via polymerization.
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Introduction: Because the mechanisms by which moral elevation triggers an individual's pro-social behavior remain unclear, this study examined the mediating role of self-control resources in the relationship between moral elevation and pro-social behavior. Methods: Experiment 1 examined the effects of moral elevation on self-control resources using two task paradigms, the Stroop task and the Go/NoGo task, with 80 college students as study participants. Experiment 2 was conducted with an additional 140 college students, using both experimental and questionnaire methods to examine the mediating role of self-control resources in the effects of moral elevation on pro-social behavior. Results: (1) The results of Experiment 1 showed that the self-control ability of the moral elevation induction group was significantly better than that of the non-induction group. The accuracy rate of self-control tasks in the induction group (0.94 ± 0.01) was significantly higher than that in the non-induction group (0.89 ± 0.01, F(1,79)=19.10, p <0.001, η2=0.50). The mean reaction time of the self-control tasks in the induction group (393.63 ± 3.5) was significantly lower than that in the non-induction group (415.38 ±7.30, F(1,79)=5.87, p =0.026, η2=0.24). (2) The results of Experiment 2 showed a significant positive correlation between moral elevation and self-control resources (r=0.46, p<0.001), a significant positive correlation between moral elevation and pro-social behavior (r=0.33, p<0.001), and a significant positive correlation between self-control resources and pro-social behavior (r=0.31, p<0.001). Not only did moral elevation significantly and positively predict pro-social behavior (ß= 0.23, p=0.011), but it also significantly and positively predicted self-control resources (ß= 0.46, p<0.001). Self-control resources significantly and positively predicted pro-social behavior (ß= 0.20, p=0.025). The bootstrap test for the mediating effect of self-control resources showed that the upper and lower limits of the 95% confidence interval did not include 0 (indirect effect 0.09, 95% CI [0.023, 0.242], p<0.001), and the mediating effect accounted for 28.13%. Conclusion: This study revealed the mediating role of self-control resources in the relationship between moral elevation and pro-social behavior, which has important theoretical and practical implications for cultivating pro-social behavior and moral education among college students.
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Background/objectives: Recently, four meta-analyses have explored the association between inflammatory bowel disease (IBD) and the risk of stroke. These studies have demonstrated that people with IBD may be at an increased risk of stroke. However, some limitations such as high heterogeneity and the lack of uniformity in the types of research, especially the reuse of some sample sizes, cannot be neglected. These factors reduce the credibility of their research conclusions. Therefore, we conducted a meta-analysis to explore this possible association. Methods: PubMed, Embase, and Web of Science were searched from inception to 30 June 2023. A random effects model with the generic inverse variance method was used in this meta-analysis. The Review Manager software was used to obtain all relative risks (RRs) and their 95% confidence intervals (CIs). Publication bias was tested, and sensitivity and subgroup analyses were conducted to explore possible heterogeneities. Results: This meta-analysis included 12 cohort studies (involving 4,495,055 individuals). Meta-analysis of these data has shown that IBD was associated with an increased risk of stroke (RR = 1.19, 95%CI:1.14-1.24, p < 0.00001). Our results were stable and robust in subgroup and sensitivity analyses. Conclusions: Our results suggest that IBD is associated with an increased risk of stroke. To reduce the incidence of stroke, patients with IBD are encouraged to undergo stroke risk assessments, especially for young female patients; assessing the risk of ischemic stroke is of particular importance. Prospective studies considering stroke subtypes, IBD severity and treatments, regions, and other confounding factors are needed to further explore the nature of each association. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022373656.
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Due to the limitations of the existing measurements of experiential avoidance, we would like to check the validity of the improved version of Acceptance and Action Questionnaire-II (AAQ-II), i.e., Acceptance and Action Questionnaire-3 (AAQ-3), in Chinese content. The present study was aim to examine the construct and validity of the Chinese version of AAQ-3 in college students and provide an initial validation of this instrument to promote future cross-cultural examination of the psychological flexibility. Totally 1,572 college students were invited to complete the Chinese AAQ-3 and the related questionnaires at the same time. After one month, 380 participates were assessed with same questionnaires to examine the test-retest reliability. The results indicated a similar one-factor solution in the Chinese AAQ-3 to the original version by exploratory factor analysis, parallel analysis and confirmatory factor analysis. Internal consistency and test-retest reliability were good. According to the testing of the measurement invariance, the one-factor model was acceptable across gender (Man = 875, Girl = 697). Additionally, Chinese AAQ-3 was significantly negatively correlated with positive mental health (life satisfaction, mindful attention awareness), significantly positively correlated with negative emotions (depression, anxiety, stress), and significantly positively correlated with AAQ-II and Brief Experiential Avoidance Questionnaire (BEAQ). Besides, Chinese AAQ-3 was the strongest predictor of depression, anxiety, stress and life satisfaction compared to the AAQ-II and BEAQ. However, according to the exploratory structural equation model, the Chinese AAQ-3 demonstrated excellent discriminate validity from negative emotions. Overall, the AAQ-3 modified the limitations of the existing measurements of experiential avoidance (i.e., AAQ-II and BEAQ) as it showed better convergent validity with positive mental health indicators, better discriminant validity with negative emotions, and higher incremental validity. Therefore, the Chinese AAQ-3 is a valid measurement tool for assessing the level of experiential avoidance or psychological flexibility in Chinese college students.
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Transtornos de Ansiedade , Ansiedade , Masculino , Feminino , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
Background: Postoperative complications are common after major surgical procedures, leading to increased morbidity and mortality. Regional cerebral oxygen saturation (rScO2) reflects cerebral and global perfusion, and thus it can be used to guide hemodynamic management. We aim to explore the effect of rScO2-guided blood pressure management strategy on postoperative major complications in older adults who undergo major noncardiac surgery. Methods: This randomized controlled clinical trial includes a total of 400 elderly patients receiving major noncardiac surgery and general anesthesia. Patients will be randomized (1:1) to one of two blood pressure management groups: a standard care group (targeting mean arterial pressure >65 mmHg or within 20% of baseline value), and a rScO2-guided group (absolute value of rScO2 >60% or decrease in rScO2 <10% of baseline). The primary outcome is the composite outcome of major complications (including infectious, respiratory, neurologic, cardiovascular, renal, thromboembolic gastrointestinal, and surgical complications) and deaths within the first 7 days after surgery. Secondary outcomes include the individual components of the primary outcome by day 7 after surgery and 30-day mortality. Data will be analyzed in the modified intention-to-treat population. Discussion: This study will provide evidence for improving postoperative outcomes using the rScO2-guided blood pressure management among older adults who undergo major noncardiac surgery. Trial Registration: Chinese Clinical Trial Registry (Identifier: ChiCTR2200060816).
This is a protocol for a prospective, randomized, controlled clinical trial to evaluate the use of intraoperative individualized regional cerebral oxygen saturation (rScO2) optimization for blood pressure management in older adults undergoing major noncardiac surgery. The primary focus of this trial is the composite outcome of major complications (including infectious, respiratory, neurologic, cardiovascular, renal, thromboembolic gastrointestinal, and surgical complications) and deaths within the first 7 days after surgery. The secondary outcomes are the individual components of the primary outcome by day 7 after surgery and 30-day mortality. The findings of this trial will provide clinical evidence for the rScO2-guided blood pressure management to improve postoperative outcomes in older patients who are scheduled for major noncardiac surgery.
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Hoarding is a common problem behavior worldwide and is detrimental to the physical and mental health of individuals and groups. Currently, effective interventions for hoarding are cognitive-behavioral therapies, but their post-intervention efficacy is questionable, and the available research does not examine the mediating variables of the effects of interventions on clinical outcomes. Moreover, current research on hoarding has focused on Western countries. Therefore, there is a need to investigate the efficacy of other forms of cognitive behavioral therapy on hoarding as well as other psychological outcomes related to hoarding and mediating variables that contribute to its effectiveness in different cultural contexts. One hundred thirty-nine college students with higher hoarding behaviors were randomly divided into three groups: 45 in the Acceptance and Commitment Therapy (ACT) group, 47 in the Rational Emotive Behavior Therapy (REBT) group, and 47 in the control group. They completed the Saving Inventory-Revised (SI-R), Obsessive-Compulsive Symptom Scale (OCSS), Difficulties in Emotion Regulation Scale (DERS), Experiences in Close Relationships Inventory-Attachment Anxiety Subscale (ECR), Depression Anxiety Stress Scales (DASS-21), Acceptance and Action Questionnaire II (AAQ-II), and Cognitive Fusion Questionnaire (CFQ) before and immediately after the intervention. The results showed that ACT and REBT improved individuals' psychological flexibility, cognitive fusion, acquisition-difficulty discarding, clutter, negative affect (anxiety, depression, stress), attachment anxiety, obsessive-compulsive disorder, and difficulty in emotion regulation compared to the control group. In addition, ACT was more effective than REBT in improving psychological flexibility and reducing hoarding, cognitive fusion, depression, stress, and obsessive-compulsive disorder; there were no significant differences between the two in anxiety and emotion regulation difficulties. Furthermore, psychological flexibility is a mediator of the effect of ACT and REBT on some behavioral and psychological outcomes (hoarding, negative affect, attachment anxiety). Limitations were discussed.
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Terapia de Aceitação e Compromisso , Transtorno de Acumulação , Transtorno Obsessivo-Compulsivo , Humanos , Ansiedade/terapia , Ansiedade/psicologia , Transtorno Obsessivo-Compulsivo/terapia , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtorno de Acumulação/psicologia , Transtorno de Acumulação/terapiaRESUMO
Objective: To examine the validity and reliability of the Chinese version of the Self-as-Context Scale (SACS) in college students. Method: We used convenience sampling to recruit 708 Chinese college students. All participants completed the SACS and 343 of them were asked to complete the validation questionnaires (Satisfaction with Life Scale, Peace of Mind Scale, Acceptance and Action Questionnaire-II, Mindful Attention Awareness Scale, Cognitive Fusion Questionnaire-Fusion, and Depression Anxiety Stress Scale-21) at the same time. We conducted items analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), measurement invariance test, correlation analysis, regression analysis, and internal consistency reliability analysis. After 3 weeks, 217 participants filled out the SACS again to assess the test-retest reliability. Results: The exploratory factor analysis showed that the SACS consisted of two factors (Centering and Transcending), with a total of 9 items. The confirmatory factor analysis demonstrated that the two-factor structure fit well (χ 2 = 55.40, df = 22, CFI = 0.977, TLI = 0.963, RMSEA = 0.065, SRMR = 0.032). According to the results of the measurement invariance tests, configural invariance, metric invariance, scalar invariance, and strict invariance of the 2-factor model, the C-SACS scores were comparable across genders. Additionally, the C-SACS total score and its subscale scores were significantly positively correlated with positive indicators of mental health (life satisfaction, affective well-being), significantly negatively correlated with negative emotions (depression, anxiety, stress), significantly negatively correlated with experiential avoidance and cognitive fusion (except for the Transcending factor), and significantly positively correlated with mindful attention and awareness. Regression analysis results revealed that the C-SACS surpasses the incremental effectiveness of AAQ-II and CFQ-F in predicting different psychological health indicators. The Cronbach's α coefficients of the C-SACS and two subscales were 0.88 [0.71, 0.90], 0.80 [0.87, 0.90] and 0.85 [0.83, 0.88] and McDonald's ω = 0.88 [0.87, 0.90], ω = 0.80 [0.78, 0.83], ω = 0.85[0.83, 0.88]. The test-retest reliability (ICC) was 0.73 and 0.72, respectively. Conclusion: The results of our study suggest that the Chinese version of SACS has good reliability and validity in Chinese college students.
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Body dissatisfaction is a global phenomenon. Despite the significant cultural difference, most research on negative body image was conducted in Western countries. How do cognitive fusion and psychological flexibility relate to negative body image in the Chinese population? In the present study, this question was investigated through the intervention technique, Acceptance and Commitment Therapy (ACT). Here, 86 young Chinese university students with high negative physical self were invited, in which 42 students received 10 sessions of group-based ACT intervention in a clinical setting while the remained acted as the control group with no intervention. Pretests showed no statistical differences in negative body image between these two groups, while both cognitive fusion and psychological flexibility predicted negative body image. Post-pre tests showed no change in the control group, while enhanced cognitive defusion and psychological flexibility in the ACT group. Individual differences in psychological flexibility and cognitive defusion enhancement predicted improved body image. A strong association of implicit body image with Fatness and Shortness changes suggested that although with individual differences, those components could be internalized during the intervention in the College students.
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Terapia de Aceitação e Compromisso , Insatisfação Corporal , Humanos , População do Leste Asiático , Estudantes/psicologia , CogniçãoRESUMO
BACKGROUND: Postherpetic neuralgia (PHN) is a common complication after herpes zoster infection. While conventional dorsal column temporary spinal cord stimulation (tSCS) has been shown as an effective treatment option for this pain condition, recent data suggests ipsilateral temporary spinal nerve root stimulation (tSNRS) as a safe alternative for treating PHN. However, there is no direct clinical comparison between the newer tSNRS and the traditional tSCS. OBJECTIVES: The current retrospective study aimed to describe the technical factors and the therapeutic efficacy of tSNR for patients with unilateral PHN and to compare these parameters with those treated with tSCS. STUDY DESIGN: Retrospective cohort study. SETTING: Single-center study in a large academic hospital. METHODS: One hundred sixty patients with unilateral PHN who underwent 7-14 days of tSCS (n = 109) or tSNRS (n = 51) treatment were included. Technical factors between the 2 groups, such as procedure time, radiation dosage, number of electrodes used, number of stimulation parameter adjustments, and average cost, were compared. Treatment efficacy, measured by analgesic coverage, pain visual analog scale (VAS), total analgesic agent consumption, Pittsburgh sleep quality index (PSQI), and physical and mental quality of life, were also compared between the 2 groups at baseline, post-procedure, and 3 months after stimulation treatment. RESULTS: Patients who underwent tSNRS reported significant improvement in pain level, sleep quality, and overall quality of life immediately postprocedure and during the follow-up period. This therapeutic effect was comparable to the tSCS group. Moreover, tSNRS achieved this therapeutic effect with a fewer number of implanted electrodes and stimulation adjustments than tSCS. The precision and consistency of the tSNRS technique were associated with a significant overall lower cost, a shorter procedure time, and less intraoperative radiation exposure in the tSNRS group than in those who received tSCS. LIMITATIONS: The current retrospective cohort study was limited by its relatively short follow-up period. Also, the selection of stimulation techniques was not randomized. CONCLUSIONS: While tSNRS provides similar therapeutic efficacy compared to tSCS for patients with unilateral PHN; it offers several technical advantages. These advantages include shorter procedure time, less radiation exposure, fewer implanted electrodes, more effective stimulation, and lower overall cost.
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Neuralgia Pós-Herpética , Estimulação da Medula Espinal , Analgésicos , Humanos , Neuralgia Pós-Herpética/etiologia , Neuralgia Pós-Herpética/terapia , Qualidade de Vida , Estudos Retrospectivos , Estimulação da Medula Espinal/métodos , Raízes Nervosas Espinhais , Resultado do TratamentoRESUMO
Effective removal of nitrogen from coking wastewaters is a great challenge, since conventional biological technologies commonly suffer from concentrated bio-toxic components such as phenolic compounds and thiocyanide (SCN-). This study has successfully developed a novel ternary process for efficiently removing nitrogen from a practical coking wastewater, by rationally combined biological pretreatment, Fenton sub-pretreatment and final partial nitrification-denitrification (PN) process. It was noted that the oxic biological pretreatment (OP) could degrade above 80 % of COD and SCN- in the wastewater, by adopting the pristine coking wastewater sludge. Fenton sub-pretreatment would further degrade the residual toxic organics and protect the metabolic activity of nitrobacteria and denitrobacteria, realizing the efficient removal of NH4+-N and TN that occurred in the final PN process with self-cultivated sludge. This work can provide an interesting strategy by rationally combining biological-physicochemical processes for nitrogen removal in toxic industrial wastewaters.
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Cocaína , Coque , Reatores Biológicos , Coque/análise , Desnitrificação , Nitrificação , Nitrogênio , Oxirredução , Esgotos , Águas Residuárias/químicaRESUMO
Heterogeneous peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) have shown a great potential for pollutant degradation, but their feasibility for large-scale water treatment application has not been demonstrated. Herein, we develop a facile coprecipitation method for the scalable production (â¼10 kg) of the Cu-Fe-Mn spinel oxide (CuFeMnO). Such a catalyst has rich oxygen vacancies and symmetry-breaking sites, which endorse it with a superior PMS-catalytic capacity. We find that the working reactive species and their contributions are highly dependent on the properties of target organic pollutants. For the organics with electron-donating group (e.g., -OH), high-valent metal species are mainly responsible for the pollutant degradation, whereas for the organics with electron-withdrawing group (e.g., -COOH and -NO2), hydroxyl radical (â¢OH) as the secondary oxidant also plays an important role. We demonstrate that the CuFeMnO-PMS system is able to achieve efficient and stable removal of the pollutants in the secondary effluent from a municipal wastewater plant at both bench and pilot scales. Moreover, we explore the application prospect of this PMS-based AOP process for large-scale wastewater treatment. This work describes an opportunity to scalably prepare robust spinel oxide catalysts for water purification and is beneficial to the practical applications of the heterogeneous PMS-AOPs.
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Óxido de Alumínio , Óxido de Magnésio , Peróxidos , Poluentes da Água , Purificação da Água , Óxido de Alumínio/química , Catálise , Óxido de Magnésio/química , Peróxidos/química , Poluentes da Água/química , Purificação da Água/métodosRESUMO
The nucleophilic superoxide radical (O2â¢-)-based dehalogenation reaction shows great potential to degrade the toxic halogenated organic compounds (HOCs). But such an O2â¢--mediated reductive reaction often suffers from the competition of the secondary oxidative species (e.g., â¢OH), leading to inferior electron efficiency and possible disinfection byproduct formation. Here, an O2â¢--dominant ultrafast dehalogenation system is developed via molecular O2 activation by the oxygen vacancy (OV)-rich CuO nanoparticles (nCuO). The nCuO delivers a remarkable dechlorination rate constant of 3.92 × 10-2 L min-1 m-2 for 2,4-dichlorophenol, much higher than that of the conventional zerovalent (bi)metals. The absorbed O2 on the nCuO surface is exclusively responsible for O2â¢- generation, and its reactivity increases with the elevated OV content because of the enhanced orbital hybridization between the O p- and Cu d-orbitals. More importantly, the ubiquitous carbonate species firmly bound to the surface OVs block the formation of the secondary oxidative species via H2O2 activation, assuring the dominant role of the in situ generated O2â¢- for the selective HOC dehalogenation. The carbonate-deactivated OVs of the nCuO can be feasibly recovered via air annealing for sustainable dehalogenation. This work provides a new opportunity for selective O2â¢- generation via interfacial defect engineering for dehalogenation and other environmental applications.