RESUMEN

Rapid urbanization brought lots of serious environmental contamination, including the accumulation of heavy metals, acid rain, and the emission of tire wear particles (TWPs), with detrimental effects for terrestrial ecosystems. Nevertheless, how naturally aged TWPs affect the mobilization of heavy metals in soils under acid rain is still unclear. Here, we investigate the adsorption and transport mechanisms of Pb(II) co-existing with acid rainwater in soil-TWP mixtures via batch experiments, column experiments and modeling. Results showed that photoaged TWP significantly prolonged the Pb(II) adsorption equilibrium time (1 to 16 h) and enhanced the Pb(II) adsorption capacity of soils. Soil column profiles confirmed that TWP effectively boosted the initial accumulation of lead in the topsoil and thus impeded the downward transport of lead. The retardation factor (R) estimated by the linear two-site sorption model (TSM) fitting the Pb(II) breakthrough curves gradually increased from 1.098 to 16.38 in soils with TWP (0-10 %). Comparative results of linear or nonlinear TSM suggested nonlinear sorption replacing linear sorption as the main Pb(II) sorption mechanism under 1 % and 10 % TWP. This research provides significant insights into the implications of TWP on the Pb(II) retention behaviors and highlights the severer potential remobilization risks of Pb(II) in urban soils under different acid rain environments.

RESUMEN

Background: Due to the widespread use of computed tomography (CT) screening and advances in diagnostic techniques, an increasing number of patients with multiple pulmonary nodules are being detected and pathologically diagnosed as synchronous multiple primary lung cancers (sMPLC). It has become a new challenge to treat multiple pulmonary nodules and obtain a favorable prognosis while minimizing the perioperative risk for patients. The purpose of this study was to summarize the preliminary experience with a hybrid surgery combining pulmonary resection and ablation for the treatment of sMPLC and to discuss the feasibility of this novel procedure with a literature review. Methods: This is a retrospective non-randomized controlled study. From January 1, 2022 to July 1, 2023, four patients underwent hybrid surgery combining thoracoscopic pulmonary resection and percutaneous pulmonary ablation for multiple pulmonary nodules. Patients were followed up at 3, 6 and 12 months postoperatively and the last follow-up was on November 30, 2023. Clinical characteristics, perioperative outcomes, pulmonary function recovery and oncologic prognosis were recorded. Meanwhile we did a literature review of studies on hybridized pulmonary surgery for the treatment of multiple pulmonary nodules. Results: All the four patients were female, aged 52 to 70 years, and had no severe cardiopulmonary dysfunction on preoperative examination. Hybrid surgery of simultaneous pulmonary resection and ablation were performed in these patients to treat 2 to 4 pulmonary nodules, assisted by intraoperative real-time guide of C-arm X-ray machine. The operation time was from 155 to 240 minutes, and intraoperative blood loss was from 50 to 200 mL. Postoperative hospital stay was 2 to 7 days, thoracic drainage duration was 2 to 6 days, and pleural drainage volume was 300-1,770 mL. One patient presented with a bronchopleural fistula due to pulmonary ablation; the fistula was identified and sutured during thoracoscopic surgery and the patient recovered well. No postoperative 90-day complications occurred. After 3 months postoperatively, performance status scores for these patients recovered to 80 to 100. No tumor recurrence or metastasis was detected during the follow-up period. Conclusions: Hybrid procedures combining minimally invasive pulmonary resection with ablation are particularly suitable for the simultaneous treatment of sMPLC. Patients had less loss of pulmonary function, fewer perioperative complications, and favorable oncologic prognosis. Hybrid surgery is expected to be a better treatment option for patients with sMPLC.

RESUMEN

Microplastics (MPs) pollution is widely investigated owing to its potential threats to river ecosystems. However, it remains unclear whether hydraulic disturbance deepens or mitigates the effects of MPs-contaminated sediments on the river environment. Herein, we studied the impact of sediment aggregates, organic matter, and enzyme activity, with emphasis on microbial community structure and function in sediments exposed to MPs (1 %, 5 %, and 10 % w/w) in conjunction with hydraulic disturbance. The experimental results showed that the influence of MPs on the sediment under hydraulic disturbance is more significant than that of static culture, especially for various environmental factors (MWD, MBC, and sucrase activity etc.). The proportions of the >0.05 mm-fraction aggregates increased from 74-76 % to 82-88 % in the sediment throughout the entire disturbance process. It has been found that the disturbance generally promotes the interaction between MPs and sediments. FAPROTAX analysis demonstrated that the disturbance reduced the difference in effects on microbial functional genes between the control group and the MPs-added groups by up to 10 times, suggesting that the effects of disturbance on MPs-contaminated sediments are relatively complex. This work provides new insights into the effects of hydraulic disturbance on physicochemical properties and microbial communities of MPs-contaminated sediment.

Asunto(s)

RESUMEN

Introducing carbon quantum dots (CQDs) into photocatalysts is believed to boost the charge transfer rate and reduce charge complexation. Doping heteroatoms such as N, S, or P enable CQDs to have an uplifting electron transfer capability. However, the application of oxygen-doped CQDs to improve the performance of photocatalysts has rarely been reported. Herein, a type of carbon-oxygen quantum dots (COQDs) was in situ embedded into MIL-53(Fe) to aid peroxydisulfate (PDS)-activated degradation of oxytetracycline (OTC) under visible light irradiation. The successful embedding of COQDs was confirmed by XRD, FT-IR, XPS, SEM, and TEM techniques. Photoelectrochemical testing confirmed its better performance. The prepared COQDs1/MIL-53(Fe) showed 88.2% decomposition efficiency of OTC in 60 min, which was 1.45 times higher than that of pure MIL-53(Fe). In addition, the performance of the material was tested at different pH, OTC concentrations, catalyst dosing, and PDS dosing. It was also subjected to cyclic testing to check stability. Moreover, free radical trapping experiments and electron paramagnetic resonance were conducted to explore the possible OTC deterioration mechanism. Our work provides a new idea for the development of MOFs for water treatment and remediation.

Asunto(s)

RESUMEN

BACKGROUND: Patients of interstitial lung disease (ILD) combined with pulmonary lesions are increasingly common in clinical practice. Patients with ILD are at significantly higher risk for complications after pulmonary resection (including lobectomy and sublobar resection), especially acute exacerbations of ILD (AE-ILD). The purpose of this study is to summarize the short-term and long-term outcomes after pulmonary resection in ILD patients and to analyze the clinical factors affecting surgical safety. METHODS: From January 2004 to January 2022, a total of 78 patients who were diagnosed with ILD and underwent pulmonary resection at our center were enrolled in this study. Clinical data, pathological findings, surgical procedures, and intraoperative safety of these patients were collected retrospectively. Postoperative 90-day complications and mortality, long-term surgical outcomes from postoperative 90 days to 24 months, and changes in ILD condition were investigated. Logistic regression analysis was used to identify the risk factors associated with postoperative complications. RESULTS: The median age of patients was 66.5 (range 33-86) years, 82.1% (64/78) of patients were male, and 78.2% (61/78) of patients had comorbidities. Idiopathic ILD and secondary ILD accounted for 86% and 14%, thoracotomy and video-assisted thoracoscopic surgery accounted for 12.8% and 87.2%, and lobectomy and sublobar resection accounted for 37.2% and 62.8%, respectively. Postoperative 90-day complications occurred in 25.6% (20/78) of patients, with pulmonary complications and AE-ILD occurring in 15.4% and 9.0% of patients, respectively. The postoperative 90-day mortality rate was 5.1% (4/78), and the cause of death was AE-ILD. Exacerbation of ILD or other complications occurred in 12.8% (10/78) of patients from postoperative 90 days to 24 months. Univariate logistic regression analysis showed that comorbidity, extent of resection, systemic lymph node dissection, operation time, intraoperative blood loss, and pathology of pulmonary lesion were associated with postoperative 90-day complications. In multivariate logistic regression analysis, age-adjusted Charlson Comorbidity Index and intraoperative blood loss were identified as independent risk factors of postoperative 90-day complications. CONCLUSIONS: Patients with ILD have a significantly higher risk of postoperative 90-day complications and mortality after pulmonary resection, especially pulmonary complications and AE-ILD. After postoperative 90 days, the risk of deterioration of pulmonary status remains high, including exacerbation of ILD and complications associated with long-term use of glucocorticoids and immunosuppressant. Age, comorbidity and intraoperative blood loss are high risk factors for postoperative 90-day complications.

Asunto(s)

RESUMEN

BACKGROUND: Thymoma and myasthenia gravis (MG) interact with each other. This study aimed to evaluate the effects of thymoma on neurological outcome of MG patients after thymectomy using the propensity score matching (PSM) method. METHODS: Consecutive patients with MG who underwent thymectomy at Beijing Hospital between January 2012 and August 2021 were retrospectively enrolled. Clinical and follow-up data were collected. Statistical analysis was performed using SPSS 23.0 software. PSM was performed to eliminate selection bias. RESULTS: A total of 456 patients were included in this study. Thymoma was present in 138 (30.3%) patients. The median follow-up time was 72 (range, 12-135) months. At the last follow-up, a lower proportion of thymomatous MG patients achieved complete stable remission (CSR) compared with non-thymomatous MG patients (P = 0.011), and the effective rate [CSR + pharmatologic remission (PR) + minimal manifestations (MM)] of thymomatous MG patients was also lower (P = 0.037). Considering time to CSR, Kaplan-Meier analysis showed thymomatous MG patients had lower cumulative CSR rate than non-thymomatous MG patients (log-rank, P = 0.019). After PSM, 105 pairs of patients were matched successfully. For the matched patients, thymomatous MG patients had a lower CSR rate and a lower effective rate (P = 0.002, 0.039, respectively), and K-M analysis still showed thymomatous MG patients had lower cumulative CSR rate (log-rank, P = 0.048). Multivariate Cox analysis demonstrated that thymoma (HR: 0.592, 95% CI 0.389-0.900, P = 0.014), older age at the time of surgery (HR: 0.971, 95% CI 0.953-0.990, P = 0.003), and preoperative course of MG > 12 months (HR: 0.474, 95% CI 0.317-0.708, P = 0.000) were negative predictive factors for CSR. CONCLUSIONS: Thymoma had a negative effect on the neurological outcome of MG after thymectomy. MG patients with old age and a preoperative course of longer than one year had a lower probability of achieving CSR.

Asunto(s)

RESUMEN

In this study, a novel catalyst based on MIL-53(Fe) was synthesized and modified through sublimed sulfur (S-MIL-53(Fe)) to induce a synergistic effect of surface adsorption and persulfate activation. The S-doped modification not only increased the surface area but also accelerated the electron transfer process of the iron cycle. The performance of the newly synthesized S-MIL-53(Fe) adsorptive catalyst was evaluated by chemical adsorption and peroxydisulfate (PDS) activated removal of an emerging pollutants, oxytetracycline (OTC). The S-MIL-53(Fe) adsorptive catalyst was able to adsorb 61.7% of OTC after 120 min, and the removal efficiency reached 84.8% within 5 min after PDS dosing. The boosting effect of sulfur on the system was confirmed by characterization analysis and experimental testing. Even after 7 cycles, the removal efficiency of S-MIL-53(Fe) (69.0%) for OTC remained superior to that of pure MIL-53(Fe) (25.1%). Additionally, the adsorption kinetics and adsorption isotherm model of the material were investigated. The possible OTC degrading process was proposed based on radical quenching and electron paramagnetic resonance (EPR). This study provides a feasible way to fabricate an S-doped MIL-53(Fe) adsorptive catalyst for the remediation of antibiotics-containing wastewater.

Asunto(s)

RESUMEN

BACKGROUND: To evaluate postoperative clinical outcomes and analyze influencing factors for patients with thymic epithelial tumors over 3 years after operation. METHODS: Patients with thymic epithelial tumors (TETs) who underwent surgical treatment in the Department of Thoracic Surgery at Beijing Hospital from January 2011 to May 2019 were retrospectively enrolled in the study. Basic patient information, clinical, pathological, and perioperative data were collected. Patients were followed up by telephone interviews and outpatient records. Statistical analyses were performed using SPSS version 26.0. RESULTS: A total of 242 patients (129 men, 113 women) with TETs were included in this study, of which 150 patients (62.0%) were combined with myasthenia gravis (MG) and 92 patients (38.0%) were not. 216 patients were successfully followed up and their complete information was available. The median follow-up period was 70.5 months (range, 2-137 months). The 3-year overall survival (OS) rate of the whole group was 93.9%, and the 5-year OS rate was 91.1%. The 3-year relapse-free survival (RFS) rate of the whole group was 92.2%, and the 5-year relapse-free survival rate was 89.8%. Multivariable COX regression analysis indicated that recurrence of thymoma was an independent risk factor for OS. Younger age, Masaoka-Koga stage III + IV, and TNM stage III + IV were independent risk factors for RFS. Multivariable COX regression analysis indicated that Masaoka-Koga staging III + IV, WHO type B + C were independent risk factors for postoperative improvement of MG. For patients with MG, the postoperative complete stable remission (CSR) rate was 30.5%. And the result of multivariable COX regression analysis showed that thymoma patients with MG with Osserman staging IIA + IIB + III + IV were not prone to achieving CSR. Compared with patients without MG, MG was more likely to develop in patients with WHO classification type B, and patients with myasthenia gravis were younger, with longer operative duration, and more likely to develop perioperative complications. CONCLUSIONS: The 5-year overall survival rate of patients with TETs was 91.1% in this study. Younger age and advanced stage were independent risk factors for RFS of patients with TETs, and recurrence of thymoma were independent risk factors for OS. In patients with MG, WHO classification type B and advanced stage were independent predictors of poor outcomes of MG treatment after thymectomy.

Asunto(s)

RESUMEN

To address the existing economic and environmental issues associated with swine wastewater (SW) treatment, a process combining up-flow anaerobic sludge blanket (UASB) and anaerobic membrane bioreactor (AnMBR) was developed and continuously operated for 137 d. Bioreactor conversion and microbial community dynamics in reactors were analyzed. The UASB-AnMBR process yielded excellent pollutants removal efficiencies of 96% and 63% for chemical oxygen demand (COD) and total phosphorous (TP), respectively. More than 60% of Firmicutes (Terrisporobacter, Turicibacter, and Clostridium sensu stricto 1), which were dominated by Methanosaeta and Methanobacterium with relative abundances of 58.6% and 36.8% in the UASB and 22.5% and 40.3% in the AnMBR, respectively, converted complex compounds into organic acids for methanogenesis. This research presented an analysis of pollutants removal and microbial dynamics of UASB-AnMBR, which significantly affected the large-scale application of UASB-AnMBR process.

Asunto(s)

RESUMEN

OBJECTIVE: To study the influencing factors of myasthenic crisis in non-thymoma myasthenia gravis (MG) patients during perioperative period. METHODS: We retrospectively analyzed a total of 387 non-thymoma MG patients who underwent extended thymoma resection in the Department of Thoracic Surgery of Beijing Hospital from February 2011 to December 2021, recorded ASA score, Osserman classification, preoperative course, pyridostigmine dosage, operation method, operation time, and intraoperative blood loss, then analyzed the factors associated with postoperative myasthenic crisis by univariate and multivariate logistic regression. RESULTS: Osserman classification IIB + III + IV (P < 0.001), history of myasthenic crisis (P = 0.013), pyridostigmine dosage greater than 240 (P < 0.001), ASA score 2 and 3 (P = 0.001) are independent risk factors for myasthenic crisis. CONCLUSION: Patients with poor Osserman classification, history of myasthenic crisis before surgery, larger preoperative dosage of pyridostigmine, and higher ASA scores should be highly alert to the occurrence of postoperative myasthenic crisis.

Asunto(s)

RESUMEN

BACKGROUND: To evaluate the surgical safety in myasthenia gravis (MG) patients aged 65 and over. METHODS: A total of 564 patients with MG who underwent surgery in the Department of Thoracic Surgery of Beijing Hospital from November 2011 to March 2022 were included in the study and divided into two groups taking the age of 65 as the boundary. Perioperative data of patients were recorded and statistically analyzed. RESULTS: Compared with young patients, FEV1, FEV1% and MVV in lung function of elderly MG patients were worse (p < 0.001, p < 0.001, p = 0.002). Postoperative drainage time was longer (p < 0.001), combined with more drainage volume (p = 0.002). The American Society of Anesthesiologists (ASA) score of elderly MG patients was higher (p < 0.001). Complications were more likely to occur (p = 0.008) after surgery and Clavien-Dindo classification (CDC) of postoperative complications was also higher (p = 0.003). Meanwhile, postoperative myasthenic crisis (POMC) was more likely to occur (p = 0.038). Logistic regression showed that lower DLCO% (p = 0.049) was an independent risk factor for postoperative complications. CONCLUSIONS: Surgical indications should be considered in each elderly MG patient on an individual basis. Moreover, most elderly MG patients safely survive the perioperative period and benefit from surgery through individualized consideration.

Asunto(s)

RESUMEN

OBJECTIVE: To study the influencing factors of myasthenic crisis in patients with myasthenia gravis during perioperative period. METHODS: A total of 564 myasthenia gravis (MG) patients who underwent standard expanded resection of thymoma/thymoma in the Department of Thoracic Surgery of Beijing Hospital from January 2011 to March 2022 were retrospectively included in the study. Clinical indicators such as gender, age, thymoma, American Society of Anesthesiologists (ASA) score, operation time, intraoperative blood loss, and some others were recorded. RESULTS: Osserman-stages IIB + III + IV (odds ratio [OR] 16.091, 95% confidence interval [CI] 5.170-50.076, p value < 0.001), the dosage of pyridostigmine bromide more than 240 mg (OR 6.462, 95% CI 3.110-13.427, p value < 0.001), ASA score 2 and 3 (OR 3.203, 95% CI 1.461-7.020, p value = 0.004), low diffusion lung capacity for carbon monoxide (DLCO%) (OR 0.981, 95% CI 0.963-1.000 p value = 0.049), and blood loss greater than 1000 ml (OR 16.590, 95% CI 1.911-144.011, p value = 0.011) were independent risk factors for myasthenic crisis. CONCLUSIONS: Patients with poor Osserman stages, higher preoperative dosage of pyridostigmine bromide, higher ASA score, poor pulmonary function (low DLCO%), and more intraoperative bleeding should be highly vigilant for the occurrence of postoperative myasthenic crisis.

Asunto(s)

RESUMEN

Fabrication of heterojunction photocatalysts is a promising strategy for enhancing photocatalytic activity. However, the study about traditional type-I heterojunction still remains to be developed. Herein, a PDIsa/BiOBr traditional type-I heterojunction was constructed by electrostatic self-assembly method, which owned improved light absorption capacity and photogenerated charge separation efficiency. The interfacial electric field and the polarization electric field of PDIsa impelled the separation of excitons. The degradation rate of ciprofloxacin (CIP) was improved by 3.2 times over the optimal PDIsa/BiOBr composite than pure BiOBr. In addition, the TOC removal efficiency reached 67.34% within 120 min. Trapping experiments and electron spin resonance (ESR) tests showed that superoxide radical (•O2-) was the most active species, and singlet oxygen (1O2) and hole (h+) played a secondary role. The work may furnish a new reference for designing BiOBr-based type-I heterojunction.

Asunto(s)

RESUMEN

BACKGROUND: Myasthenia gravis (MG) patients are reported to have a high risk of other autoimmune diseases (ADs), and thymectomy may increase the risk further. A cohort of MG patients in which thymectomy was performed were investigated to analyze the prevalence, types and features of the new onset ADs. METHODS: Consecutive patients with MG who underwent thymectomy at Beijing Hospital between January 2012 and August 2021 were retrospectively enrolled. Patients with a postoperative follow-up period shorter than a year or incomplete clinical records were excluded. Clinical and follow-up data were collected. Statistical analyses were performed using SPSS version 22.0. RESULTS: A total of 445 patients were included in this study. The median follow-up period was 72 months (range, 12-135 months). A total of 63 (14.2%) MG patients had concurrent ADs. The incidence rate was higher than the background prevalence of population (5%), and also higher than that of a former Chinese MG cohort (11.6%). A total of 47 patients (10.6%) were diagnosed with ADs before thymectomy, and 19 (4.3%) developed a new AD after thymectomy. The most common types of new onset ADs after thymectomy were Hashimoto's thyroiditis and rheumatoid arthritis (RA), which were different from those before thymectomy (hyperthyroidism and Hashimoto's thyroiditis). The incidence rate of new onset RA (1.35%) was higher than the frequency of RA before thymectomy (0.45%), and also higher than the incidence rate in a Chinese MG cohort (0.5%). There was a higher proportion of female patients (p = 0.026) with postoperative ADs. A younger age at operation may increase the risk of nonthymoma MG patients (p = 0.040) developing ADs. The postoperative treatment effect of MG was similar between patients with and without new onset ADs (p > 0.05). CONCLUSIONS: We observed a higher incidence rate of autoimmune diseases, especially rheumatoid arthritis, in MG patients after thymectomy. The most common types of ADs after thymectomy were different from those before thymectomy. New onset ADs tended to occur in female and young nonthymoma MG patients. The postoperative effect of MG was not related with the new occurrence of ADs.

Asunto(s)

RESUMEN

Background: Thymic neuroendocrine neoplasms (Th-NENs) are extremely rare. Th-NENs are divided into four pathological subtypes: typical carcinoid (TC), atypical carcinoid (AC), large cell neuroendocrine carcinoma (LCNEC), and small cell carcinoma (SCC). The latter three subtypes are highly aggressive with poor prognosis. There are limited reports on the optimal surgical strategies for Th-NENs. This study aims to report a case series of Th-NENs after surgical treatment and review the literatures. Methods: We report a case series of five patients diagnosed with Th-NENs and summarize their clinical characteristics. Literatures related to surgical treatment of Th-NENs were reviewed. Results: There were three males and two females, and mean age was 53.6 years. No myasthenia gravis or neuroendocrine symptoms were found. Three patients were diagnosed with AC and the other two were diagnosed with LCNEC. Two patients were stage II-b, one patient was stage III-a, and two patients were stage IV-b. One patient received preoperative chemotherapy, one patient received preoperative chemoradiotherapy, and three patients underwent surgery directly. Two patients underwent extended thymectomy via video-assisted thoracoscopic surgery (VATS), two patients underwent extended thymectomy via median sternotomy, and one patient underwent resection of anterior mediastinal tumor, sternal metastases, superior vena cava and partial right atrium via median sternotomy and cardiopulmonary bypass. R0 resection was achieved in 80% (4/5) of patients. There was no postoperative 90-day complication and death. One patient had no recurrence. One patient had lymph node metastases and was still alive after somatostatin analogue therapy. One patient had no recurrence of Th-NENs but died of other tumors. Two patients had distant metastases. Median overall survival (mOS) was 49 (range, 4-134) months. A total of 22 original studies related to surgical treatment of Th-NENs were retrieved. Conclusions: Th-NENs is a very rare and extremely aggressive malignancy. Early diagnosis and surgical resection are the most important methods to improve prognosis. Radical resection and lymph node dissection are recommended for accurate staging and better prognosis. Currently, there are few clinical data on Th-NENs and several important surgical issues remain unresolved. In the future, multi-center, large-sample database and clinical studies are urgently needed to explore better treatment modality.

RESUMEN

OBJECTIVE: The purpose of this study was to introduce a new feasible and effective intraoperative localization technique for small peripheral pulmonary nodules in hybrid operating room. METHODS: Between June 2020 and June 2021, the intraoperative localization was performed in 27 patients for 35 small pulmonary nodules at our institution. The procedure was undergone under thoracoscopic observation. After making the VATS ports, a titanium clip was clipped at the visceral pleura as near the pulmonary nodule as possible to be a marker for the nodule. VATS resection was performed next. RESULTS: A total of 27 patients were included in this study, including 6 males and 21 females. The median age was 58 years (range 34-78 years). All surgeries were performed by two-port VATS. A total of 35 pulmonary nodules underwent intraoperative localization. The mean diameter of nodules was 10.6 ± 3.7 mm. The distance of nodules to visceral pleura was 8.3 ± 8.7 mm. The mean localization time was 23.3 ± 3.3 min. The median time of C-arm scanning was 3 (range 2-4) times. The median times for clipping were 2 (range 1-3) times. All the nodules were localized successfully and resected precisely. No VATS were converted to thoracotomy. There were no complications related to localization procedures. CONCLUSIONS: This new intraoperative localization technique was feasible, safe and effective. And also the intraoperative procedure could avoid extra suffering for patients.

Asunto(s)

RESUMEN

A novel magnetic nanocomposite MIL-101(Fe)/γ-Fe2O3 was synthesized by hydrothermal method. The physical structure and chemical property of the as-obtained magnetic nanocomposite was characterized. The ability of MIL-101(Fe)/γ-Fe2O3 to promote photo-assisted peroxydisulfate (PDS) activation was investigated by using oxytetracycline (OTC) as the target pollutant. The results showed that the composite with a FeCl3•6H2O: γ-Fe2O3 mass ratio of 10:1 exhibited the highest degradation efficiency (up to 91.2%). Influencing factors such as pH, catalyst dosage, PDS concentration and OTC concentration on the catalytic performance of MIL-101(Fe)/γ-Fe2O3 were also investigated to determine the optimum conditions. More importantly, the MIL-101(Fe)/γ-Fe2O3 can be magnetically recovered and reused for 4 cycles. Based on radical quenching and electron spin resonance (ESR), the possible degradation mechanism of OTC in photo-assisted PDS activation (PPA) system was proposed. This research provided novel insights for the design and preparation of a new type of magnetic Fe-MOFs for environmental remediation.

Asunto(s)

RESUMEN

The widespread distribution of persistent organic pollutants (POPs) in natural waters has aroused global concern due to their potential threat to the aquatic environment. Photocatalysis represents a promising mean to remediate polluted waters with the simple assistance of solar energy. Herein, we fabricated a Co-Cl bond reinforced CoAl-LDH/Bi12O17Cl2 heterogeneous photocatalyst to investigate the feasibility of photocatalysis to treat POPs-polluted water under environmental conditions. The optimum CoAl-LDH/Bi12O17Cl2 (5-LB) composite photocatalyst exhibited excellent photocatalytic performance, which could degrade 92.47 % of ciprofloxacin (CIP) and 95 % of bisphenol A (BPA) with 2h of actual solar light irradiation in Changsha, China (N 28.12 °, E 112.59 °). In view of the synergistic influence of water constituents, various water matrices greatly affected the degradation rate of CIP (BPA), with the degradation efficiency of 82.17% (84.37%) in tap water, 69.67% (71.63%) in wastewater effluent, and 44.07% (67.7%) in wastewater inflow. The results of electron spin resonance, and chemical trapping experiment, HPLC-MS and density functional theory calculation reflected that the degradation of CIP was mainly attributed to h+ and 1O2 attacking the active atoms of CIP molecule with high Fukui index. Furthermore, the non-toxicity of both 5-LB photocatalyst and treated CIP solution was proved by E.coli and B.subtilis cultivation, which further demonstrated the feasibility of the 5-LB to treat POPs in real water under irradiation of solar light.

Asunto(s)

RESUMEN

Microplastics (MPs) have recently attracted much attention due to their widespread distribution in the aquatic environment. Microplastics can act as a vector of heavy metals in the aquatic environment, causing a potential threat to aquatic organisms and human health. This review mainly summarized the occurrence of microplastics in the aquatic environment and their interaction with heavy metals. Then, we considered the adsorption mechanisms of MPs and heavy metals, and further critically discussed the effects of microplastics properties and environmental factors (e.g., pH, DOM, and salinity) on the adsorption of heavy metals. Finally, the potential risks of combined exposure of MPs and heavy metals to aquatic biota were briefly evaluated. This work aims to provide a theoretical summary of the interaction between MPs and heavy metals, and is expected to serve as a reference for the accurate assessment of their potential risks in future studies.

Asunto(s)

RESUMEN

Organic semiconductors have been recognized as a new generation of photocatalysts for pollutants degradation and energy production. Herein, organic heterojunction (TpMa/CN) consisting of carbon nitride and ß-ketoenamine-based covalent organic framework is fabricated via a controllable self-assembly approach. The as-prepared TpMa/CN heterojunctions show enlarged visible-light absorption. The optimum TpMa/CN-5 photocatalyst achieves the highest photocatalytic activity towards tetracycline degradation, and its photocatalytic degradation rate is improved by 2.3 and 4.3 times than TpMa and CN, respectively. As a multifunctional photocatalyst, TpMa/CN-5 sample also shows remarkable photocatalytic activity for hydrogen peroxide production (880.494 µM h-1), which is 49 times higher than that of CN. Experimental and theoretical investigations indicate that a built-in electric field is formed at the interface of composite, which enables an accelerated charge transfer and separation. This work develops an effective strategy to design difunctional photocatalyst and deciphers the electronic properties and mechanisms of g-C3N4-based organic photocatalysts, which spurs further interests for organic heterojunction photocatalysts in the future.

Asunto(s)