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1.
Surgery ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38997865

RESUMEN

BACKGROUND: The objective of the present study was to evaluate the effect of dexmedetomidine administration during video-assisted thoracoscopic surgery for lung cancer on perioperative inflammatory response and chronic post-surgical pain. METHODS: A cohort of 152 patients with lung cancer scheduled for elective video-assisted thoracoscopic surgery participated in this randomized controlled trial. Patients were randomly divided into 2 groups and administered an equivalent volume of dexmedetomidine (n = 63) or normal saline (n = 63). Dexmedetomidine was administered at a dose of 0.6 µg/kg 10 minutes before anesthesia induction and maintained at 0.5 µg/kg/h until 0.5 hours before surgery completed. Anesthesia and postoperative pain management protocols were standardized for both groups. The analysis included vital signs, numerical rating scales of pain, blood inflammatory and oxidative stress biomarkers, pain type and location, patient-controlled intravenous analgesia usage, consumption of general anesthetics and pain rescue medications, as well as complications. RESULTS: The administration of dexmedetomidine resulted in decreased levels of inflammatory cytokines (interleukin-1 beta, interleukin-6, alongside tumor necrosis factor-alpha) and oxidative stress biomarkers (reactive oxygen species alongside malondialdehyde) but elevated levels of interleukin-10 and superoxide dismutase. In addition, the dexmedetomidine group showed lower postoperative numerical rating scale scores, reduced consumption of anesthetics, faster chest-tube removal, fewer patient-controlled intravenous analgesia presses, and shorter postoperative hospital stays. CONCLUSION: The administration of dexmedetomidine effectively attenuated surgical inflammation, oxidative stress, and postoperative pain, thereby promoting patient recovery after lung cancer surgery without increasing the risk of adverse effects or complications.

2.
J Phys Chem Lett ; 15(19): 5150-5158, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38712816

RESUMEN

Intrinsic boundaries formed by grain stacks of randomly oriented perovskite crystallites seriously restrict charge transport in the resultant photovoltaic devices, whereas direct passivation of these defects remains unexplored, and it is desirable to modulate perovskite growth with uniform orientation. Herein, we report a simple but effective method to regulate perovskite crystallization by employing a volatile and polymerizable monomer of hydroxyethyl methacrylate (HEMA), which can simultaneously interact with both FA+ and Pb2+ via hydrogen and coordination bonding, respectively, to seed perovskite crystallization with accelerated nucleation and retarded crystal growth. Upon thermal annealing, the gradual volatilization and partial self-condensation of the HEMA drive the perovskite growth perpendicularly to the substrate, leading to largely suppressed defect states, improved crystallinity, and a reduced Young's modulus of the perovskite film. As a result, champion efficiencies exceeding 24 and 22% with improved operational and mechanical stability of the optimized perovskite solar cells based on rigid and flexible substrates were finally achieved.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38684422

RESUMEN

PURPOSE: The study aims to assess the effects of dexmedetomidine (Dex) pretreatment on patients during cardiac valve replacement under cardiopulmonary bypass. METHODS: For patients in the Dex group (n = 52), 0.5 µg/kg Dex was given before anesthesia induction, followed by 0.5 µg/kg/h pumping injection before aortic occlusion. For patients in the control group (n = 52), 0.125 ml/kg normal saline was given instead of Dex. RESULTS: The patients in the Dex group had longer time to first dose of rescue propofol than the control group (P = 0.003). The Dex group required less total dosage of propofol than the control group (P = 0.0001). The levels of cardiac troponin I (cTnI), creatine kinase isoenzyme MB (CK-MB), malondialdehyde (MDA), and tumor necrosis factor-α (TNF-α) were lower in the Dex group than the control group at T4, 8 h after the operation (T5), and 24 h after the operation (T6) (P <0.01). The Dex group required less time for mechanical ventilation than the control group (P = 0.003). CONCLUSION: The study suggests that 0.50 µg/kg Dex pretreatment could reduce propofol use and the duration of mechanical ventilation, and confer myocardial protection without increased adverse events during cardiac valve replacement.


Asunto(s)
Biomarcadores , Puente Cardiopulmonar , Dexmedetomidina , Implantación de Prótesis de Válvulas Cardíacas , Propofol , Respiración Artificial , Troponina I , Dexmedetomidina/administración & dosificación , Dexmedetomidina/efectos adversos , Humanos , Puente Cardiopulmonar/efectos adversos , Masculino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Femenino , Factores de Tiempo , Persona de Mediana Edad , Resultado del Tratamiento , Propofol/efectos adversos , Propofol/administración & dosificación , Biomarcadores/sangre , Troponina I/sangre , Forma MB de la Creatina-Quinasa/sangre , Agonistas de Receptores Adrenérgicos alfa 2/efectos adversos , Agonistas de Receptores Adrenérgicos alfa 2/administración & dosificación , Factor de Necrosis Tumoral alfa/sangre , Malondialdehído/sangre , Anciano , Adulto , Anestésicos Intravenosos/efectos adversos , Anestésicos Intravenosos/administración & dosificación , Daño por Reperfusión Miocárdica/prevención & control , Daño por Reperfusión Miocárdica/etiología
4.
J Cardiothorac Surg ; 19(1): 20, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263060

RESUMEN

BACKGROUND: Emergent airway occurrences pose a significant threat to patient life. Extracorporeal membrane oxygenation (ECMO) has been proven to be an effective method for managing emergent airways. METHODS: A retrospective analysis was conducted on all patients receiving ECMO as an adjunct for emergent airway management from January 2018 to December 2022 at the People's Hospital of Zhongshan City. We collected the basic information of the patients, their blood gas data before and after ECMO, the related parameters of ECMO, and the outcome and then analyzed and summarized these data. RESULTS: Six patients, with an average age of 51.0(28-66) years, received veno-venous (VV)- ECMO as an adjunct due to emergent airway issues. The average ECMO support duration was 30.5(11-48) hours. All six patients were successfully weaned off ECMO support, with five (83.3%) being successfully discharged after a hospital stay of 15.5(7-55) days. All six patients underwent VV-ECMO through femoral-internal jugular vein cannulation. Among these, five patients, whose airway obstruction was due to hemorrhage, underwent a non-anticoagulant ECMO strategy with no recorded thrombotic events. CONCLUSIONS: The rapid establishment of ECMO support is aided by the establishment of a standardized ECMO initiation protocol and the formation of a multidisciplinary rapid-response ECMO team, which is particularly crucial for emergent airway management. When airway obstruction results from hemorrhagic factors, the early adoption of a non-anticoagulant ECMO strategy can be considered when implementing VV-ECMO.


Asunto(s)
Obstrucción de las Vías Aéreas , Oxigenación por Membrana Extracorpórea , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Manejo de la Vía Aérea , Venas Braquiocefálicas
6.
Front Cardiovasc Med ; 10: 1200553, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37363099

RESUMEN

Introduction: Massive pulmonary embolism (PE) is a life-threatening complication of major surgery with a mortality rate of up to 50%. Extracorporeal membrane oxygenation (ECMO) is primarily used for respiratory and circulatory support. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is used to stabilize patients with acute massive PE. Acute brain injury, vascular disease, and immunosuppression are contraindications to ECMO, as stated in the 2021 Extracorporeal Life Support Organization guidelines. Case summary: We report a case of a patient with craniocerebral trauma whose postoperative course was complicated by massive PE and subsequent cardiac arrest that required urgent VA-ECMO, followed by anticoagulation with heparin. The patient showed hemodynamic improvement and was discharged 68 days after hospitalization. Discussion: ECMO has gradually been accepted for patients with craniocerebral injuries. The safety and effectiveness of ECMO in patients with craniocerebral injury, along with the optimal duration of ECMO and anticoagulation strategies, require further study.

7.
Int J Biochem Cell Biol ; 155: 106359, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36586532

RESUMEN

Although Bcl-xL has been shown to retrotranslocate Bax from mitochondria to cytosol, other studies have found that Bcl-xL also stabilizes the mitochondrial localization of Bax. It is still unclear what causes the difference in Bcl-xL-regulated Bax localization. Bad, a BH3-only protein with a high affinity for Bcl-xL, may play an important role in Bcl-xL-regulated Bax shuttling. Here, we found that Bcl-xL enhanced both translocalization and retrotranslocation of mitochondrial Bax, as evidenced by quantitative co-localization, western blots and fluorescence loss in photobleaching (FLIP) analyses. Notably, Bad knockdown prevented Bcl-xL-mediated Bax retrotranslocation, indicating Bad was essential for this process. Quantitative fluorescence resonance energy transfer (FRET) imaging in living cells and co-immunoprecipitation analyses showed that the interaction of Bcl-xL with Bad was stronger than that with Bax. The Bad mimetic ABT-737 dissociated Bax from Bcl-xL on isolated mitochondria, suggesting that mitochondrial Bax was directly liberated to cytosol due to Bad binding to Bcl-xL. In addition, MK-2206, an Akt inhibitor, decreased Bad phosphorylation while increasing cytosolic Bax proportion. Our data firmly demonstrate a notion that Bad binds to mitochondrial Bcl-xL to release Bax, resulting in retrotranslocation of Bax to cytosol, and that the amount of Bad involved is regulated by Akt signaling.


Asunto(s)
Apoptosis , Proteínas Proto-Oncogénicas c-akt , Proteína X Asociada a bcl-2/metabolismo , Proteína bcl-X/metabolismo , Citosol/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
9.
Environ Res ; 219: 115142, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36566968

RESUMEN

Humic substances (HS) can facilitate electron transfer during biogeochemical processes due to their redox properties, but the structure-redox activity relationships are still difficult to describe and poorly understood. Herein, the linear (Partial Least Squares regressions; PLS) and nonlinear (artificial neural network; ANN) models were applied to monitor the structure dependence of HS redox activities in terms of electron accepting (EAC), electron donating (EDC) and overall electron transfer capacities (ETC) using its physicochemical features as input variables. The PLS model exhibited a moderate ability with R2 values of 0.60, 0.53 and 0.65 to evaluate EAC, EDC and ETC, respectively. The variable influence in the projection (VIP) scores of the PLS identified that the phenols, quinones and aromatic systems were particularly important for describing the redox activities of HS. Compared with the PLS model, the back-propagation ANN model achieved higher performance with R2 values of 0.81, 0.65 and 0.78 for monitoring the EAC, EDC and ETC, respectively. Sensitivity analysis of the ANN separately identified that the EAC highly depended on quinones, aromatics and protein-like fluorophores, while the EDC depended on phenols, aromatics and humic-like fluorophores (or stable free radicals). Additionally, carboxylic groups were the best indicator for evaluating both the EAC and EDC. Good model performances were obtained from the selected features via the PLS and sensitivity analysis, further confirming the accuracy of describing the structure-redox activity relationships with these analyses. This study provides a potential approach for identifying the structure-activity relationships of HS and an efficient machine-learning model for predicting HS redox activities.


Asunto(s)
Electrones , Sustancias Húmicas , Sustancias Húmicas/análisis , Oxidación-Reducción
12.
Heart Surg Forum ; 25(3): E449-E451, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35787762

RESUMEN

BACKGROUND: Using tourniquets in the lower extremities can increase the incidence of deep vein thrombosis (DVT). Acute large-area pulmonary embolism (APE) occurs in severe cases, and it is fatal to most patients. Acute large-area pulmonary embolism causes haemodynamic instability, right heart failure, and circulatory failure. CASE PRESENTATION: A 47-year-old female patient was subjected to spinal anaesthesia for a comminuted fracture of the tibia and fibula of the left lower limb. After the tourniquet was released during the operation, she had sudden hypotension and lost consciousness. Thus, ECMO was used to support patient circulation. With ECMO-assisted CT examination, she was diagnosed to have a pulmonary embolism. On the next day, she was subjected to a bilateral pulmonary embolism and embolectomy. Lastly, she was transferred to the general ward and discharged smoothly. CONCLUSIONS: Patients undergoing fracture surgery should be wary of APE caused by the loss of DVT after the release of tourniquets. ECMO, as a rapid and effective temporary life support intervention, provides effective cardiopulmonary support and new treatment plans. It also saves time for further treatment of patients with high-risk APE.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Embolia Pulmonar , Enfermedad Aguda , Oxigenación por Membrana Extracorpórea/efectos adversos , Femenino , Humanos , Extremidad Inferior , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiología , Embolia Pulmonar/terapia , Torniquetes/efectos adversos
13.
RSC Adv ; 12(21): 13045-13051, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35520145

RESUMEN

Bacterial infection poses severe threats to public health, and early rapid detection of the pathogen is critical for controlling bacterial infectious diseases. Current methods are commonly labor intensive, time consuming or dependent on lab-based equipment. In this study, we proposed a novel and practical method for bacterial detection based on smartphones using the surface plasmon resonance (SPR) phenomena of gold nanoparticles (AuNPs). The proposed smartphone-based SPR sensing method is achieved by utilizing color development that arises from the change in interparticle distance of AuNPs induced by bacterial lysate. The pictures of bacteria/AuNPs color development were captured, and their color signals were acquired through a commercial smartphone. The proposed method has a detection range between 2.44 × 105 and 1.25 × 108 cfu mL-1 and a detection limit of 8.81 × 104 cfu mL-1. Furthermore, this method has acceptable recoveries (between 85.7% and 95.4%) when measuring spiked real waters. Combining smartphone-based signal reading with AuNP-dependent color development also offers the following advantages: easy-to-use, real-time detection, free of complex equipment and low cost. In view of these features, this sensing platform would have widespread applications in the fields of medical, food, and environmental sciences.

14.
RSC Adv ; 12(3): 1675-1681, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-35425161

RESUMEN

Rapid measurement of waterborne bacterial viability is crucial for ensuring the safety of public health. Herein, we proposed a colorimetric assay for rapid measurement of waterborne bacterial viability based on a difunctional gold nanoprobe (dGNP). This versatile dGNP is composed of bacteria recognizing parts and signal indicating parts, and can generate color signals while recognizing bacterial suspensions of different viabilities. This dGNP-based colorimetric assay has a fast response and can be accomplished within 10 min. Moreover, the proposed colorimetric method is able to measure bacterial viability between 0% and 100%. The method can also measure the viability of other bacteria including Staphylococcus aureus, Shewanella oneidensis, and Escherichia coli O157H7. Furthermore, the proposed method has acceptable recovery (95.5-104.5%) in measuring bacteria-spiked real samples. This study offers a simple and effective method for the rapid measurement of bacterial viability and therefore should have application potential in medical diagnosis, food safety, and environmental monitoring.

15.
Medicine (Baltimore) ; 100(30): e26798, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34397736

RESUMEN

INTRODUCTION: Patients with coronavirus disease (COVID-19) may develop acute respiratory distress syndrome (ARDS). There have been few reports of postpartum woman with ARDS secondary to COVID-19 who required respiratory support using veno-venous extracorporeal membrane oxygenation (ECMO). We present the case of a 31-year-old woman who was admitted to hospital at 35 weeks gestation with ARDS secondary to COVID-19 and required ECMO during the postpartum period. PATIENT CONCERNS: The patient had obvious dyspnea, accompanied by chills and fever. Her dyspnea worsened and her arterial oxygen saturation decreased rapidly. DIAGNOSIS: ARDS secondary to COVID-19. INTERVENTIONS: Emergency bedside cesarean section. Medications included immunotherapy (thymosin α 1), antivirals (lopinavir/ritonavir and ribavirin), antibiotics (imipenem-cilastatin sodium and vancomycin), and methylprednisolone. Ventilatory support was provided using invasive mechanical ventilation. This was replaced by venous-venous ECMO 5 days postpartum. ECMO management focused on blood volume control, coagulation function adjustment, and airway management. OUTCOMES: The patient was successfully weaned for ECMO and the ventilator and made a good recovery. CONCLUSION: Special care, including blood volume control, coagulation function adjustment, and airway management, should be provided to postpartum patients with ARDS secondary to COVID-19 who require ECMO support.


Asunto(s)
COVID-19/complicaciones , Oxigenación por Membrana Extracorpórea , Periodo Posparto , Complicaciones Infecciosas del Embarazo/virología , Adulto , COVID-19/terapia , Cesárea , Oxigenación por Membrana Extracorpórea/métodos , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/terapia
16.
World J Clin Cases ; 9(8): 1953-1967, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33748247

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2, is a worldwide pandemic. Some COVID-19 patients develop severe acute respiratory distress syndrome and progress to respiratory failure. In such cases, extracorporeal membrane oxygenation (ECMO) treatment is a necessary life-saving procedure. CASE SUMMARY: Two special COVID-19 cases-one full-term pregnant woman and one elderly (72-year-old) man-were treated by veno-venous (VV)-ECMO in the Second People's Hospital of Zhongshan, Zhongshan City, Guangdong Province, China. Both patients had developed refractory hypoxemia shortly after hospital admission, despite conventional support, and were therefore managed by VV-ECMO. Although both experienced multiple ECMO-related complications on top of the COVID-19 disease, their conditions improved gradually. Both patients were weaned successfully from the ECMO therapy. At the time of writing of this report, the woman has recovered completely and been discharged from hospital to home; the man remains on mechanical ventilation, due to respiratory muscle weakness and suspected lung fibrosis. As ECMO itself is associated with various complications, it is very important to understand and treat these complications to achieve optimal outcome. CONCLUSION: VV-ECMO can provide sufficient gas exchange for COVID-19 patients with acute respiratory distress syndrome. However, it is crucial to understand and treat ECMO-related complications.

17.
Heart Surg Forum ; 24(1): E019-E021, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33635242

RESUMEN

Pneumonia caused by coronavirus disease 2019 (COVID-19) is a highly contagious disease. Unfortunately, research on extracorporeal membrane oxygenation (ECMO) assisted treatments for patients with COVID-19 infection is limited. In this case study, a patient who was in late pregnancy (35+2 weeks of pregnancy) and suffering from severe COVID-19 was extremely irritable during ECMO-assisted treatment after she underwent a cesarean section. Her Richmond Agitation Sedation Scale (RASS) score reached +3. Nevertheless, the patient successfully was treated with a continuous single/combined application of propofol, midazolam, dexmedetomidine, hibernation mixture, and other drugs for several days (maintaining RASS -2 to -4) and provided with anti-infection, mechanical ventilation, nutritional support, fluid balance under hemodynamic monitoring, liver support, and other organ function support treatments. ECMO-assisted sedation strategy for patients was introduced and discussed in this case to provide a certain reference for the clinical diagnosis and treatment of such patients.


Asunto(s)
COVID-19/terapia , Cesárea , Dexmedetomidina/administración & dosificación , Oxigenación por Membrana Extracorpórea , Hipnóticos y Sedantes/administración & dosificación , Midazolam/administración & dosificación , Propofol/administración & dosificación , Terapia Combinada , Femenino , Fluidoterapia , Humanos , Monitoreo Fisiológico , Apoyo Nutricional , Embarazo , Respiración Artificial , SARS-CoV-2
18.
Heart Surg Forum ; 23(3): E305-E309, 2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32524974

RESUMEN

BACKGROUND: Lower limb ischemia in patients with extracorporeal membrane oxygenation (ECMO) via femoral artery catheterization negatively affects patient mortality and survivors' quality of life [Gulkarov 2020]. In this study, ECMO was established via femoral artery catheterization. This study aimed to identify the risk factors of lower limb ischemia to provide sufficient evidence for its prevention. METHODS: All patients with venoarterial (VA) ECMO via femoral artery catheterization in Zhongshan People's Hospital from January 2008 to November 2019 retrospectively were analyzed. Patients' general information and ECMO-related information were obtained, and the main outcome variables were survival and discharge and intubation-related adverse events (limb ischemia and incision bleeding). Logistic regression analysis was used to determine the independent risk factors of limb ischemia in patients with VA ECMO. RESULTS: A total of 179 (98 [54.7%] men and 81 [45.3%] women) eligible patients were included in this study. Moreover, a total of 90 patients (48.9%) had low cardiac output, 41 (22.3%) had acute myocardial infarction, and 33 (17.9%) had fulminant myocarditis. Eighty-six (48.04%) patients survived to hospital discharge, 36 (20.11%) had limb ischemia, and 42 (23.46%) had incision bleeding. Furthermore, the ECMO-assisted time was 114.23 ± 67.88 hours. There was no significant difference in age, sex, and Sequential Organ Failure Assessment score between the limb ischemia group and the non-limb ischemia group. Multivariate logistic regression analysis showed that peripheral artery disease (odds ratio, 27.12; 95% confidence interval, 5.614-130.96) was an independent risk factor of limb ischemia in patients with ECMO. CONCLUSION: Limb ischemia is a common complication in patients with VA ECMO, and peripheral artery disease is an independent risk factor of limb ischemia in patients with VA ECMO via femoral artery catheterization.


Asunto(s)
Cateterismo Periférico/efectos adversos , Oxigenación por Membrana Extracorpórea/efectos adversos , Arteria Femoral , Isquemia/etiología , Extremidad Inferior/irrigación sanguínea , Femenino , Vena Femoral , Estudios de Seguimiento , Humanos , Isquemia/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
19.
Environ Pollut ; 254(Pt A): 113040, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31421579

RESUMEN

Triphenyl phosphate (TPHP) is one of the major organophosphate esters (OPEs) with increasing consumption. Considering its largely distribution and high toxicity in aquatic environment, it is important to explore an efficient treatment for TPHP. This study aimed to investigate the accelerated degradation of TPHP in a three-electrode single chamber bioelectrochemical system (BES). Significant increase of degradation efficiency of TPHP in the BES was observed compared with open circuit and abiotic controls. The one-order degradation rates of TPHP (1.5 mg L-1) were increased with elevating sodium acetate concentrations and showed the highest value (0.054 ±â€¯0.010 h-1) in 1.0 g L-1 of sodium acetate. This result indicated bacterial metabolism of TPHP was enhanced by the application of micro-electrical field and addition acetate as co-substrates. TPHP could be degraded into diphenyl phosphate (DPHP), hydroxyl triphenyl phosphate (OH-TPHP) and three byproducts. DPHP was the most accumulated degradation product in BES, which accounted more than 35.5% of the initial TPHP. The composition of bacterial community in BES electrode was affected by the acclimation by TPHP, with the most dominant bacteria of Azospirillum, Petrimonas, Pseudomonas and Geobacter at the genera level. Moreover, it was found that the acute toxic effect of TPHP to Vibrio fischeri was largely removed after the treatment, which revealed that BES is a promising technology to remove TPHP threaten in aquatic environment.


Asunto(s)
Retardadores de Llama , Modelos Químicos , Organofosfatos/química , Radical Hidroxilo , Cinética , Organofosfatos/metabolismo , Fosfatos
20.
Sci Total Environ ; 696: 133895, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31465929

RESUMEN

Dissolved organic carbons in biochar (BDOM), obtained from thermal treatment (i.e., pyrolysis) of biomass, is of great importance due to their excellent redox properties and capacity to remove contaminants from the aqueous and soil environment. However, little is known about the intimate relationship between redox activity of BDOM and pyrolysis temperatures of the biomass. In this study, BDOMs were extracted from wheat straw biochar at different temperatures (from 300 °C to 700 °C). The physicochemical analyses indicated that the quinone and aromatic moieties in BDOM increased with the increase in pyrolysis temperature up to 500 °C, and then decreased as the temperature continued to rise. The results of electrochemical analysis revealed that the electron transfer capability (ETC) reached a maximum for the BDOM-500 with an electron donor capability (EDC) of 0.14 mmole- (g C)-1 and electron accepting capability (EAC) of 0.31 mmole- (g C)-1, which were both significantly higher than that of other as-prepared BDOMs. The EAC and EDC of BDOM samples both followed the order BDOM-500 > BDOM-400 > BDOM-600 > BDOM-300 > BDOM-700, demonstrating that the quinone and aromatic groups highly contributed to the redox activity of the BDOM. For Cr(VI) removal, the highest removal efficiency (~77%) was achieved in the presence of BDOM-500 and lactate as an electron donor, which was consistent with the profiles of ETC. These findings present a guidance for the optimization of BDOM that efficiently mediates pollutants removal for environmental remediation.


Asunto(s)
Carbón Orgánico/química , Restauración y Remediación Ambiental/métodos , Modelos Químicos , Pirólisis , Electrones , Triticum
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