Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 62
Filter
1.
Front Pediatr ; 12: 1345458, 2024.
Article in English | MEDLINE | ID: mdl-38859981

ABSTRACT

Objective: The purpose of this study is to evaluate the efficacy of Vitamin A (VitA) as an adjuvant therapy for pediatric Mycoplasma Pneumoniae Pneumonia (MPP) through meta-analysis, and to investigate its impact on inflammation levels (IL-6, IL-10), in order to explore the role of VitA in pediatric MPP. Methods: Using a systematic literature search method, relevant research literature is searched, and RCT studies that meet the requirements are selected based on preset inclusion and exclusion criteria. Then, a quality evaluation was conducted on the included literature, and meta-analysis was used to calculate the combined effect values of mortality rate, hospital stay, lung rale disappearance time, cough duration, fever duration, IL-6 and IL-10 levels, and heterogeneity analysis was conducted. The levels of IL-6 and IL-10 represent the inflammatory levels in pediatric MPP patients, and exploring their changes has significant implications for the anti-inflammatory effect of treatment. Results: A total of 10 RCT studies were included, with a total sample size of 1,485, including 750 cases in the control group and 735 cases in the observation group. The meta-analysis results of this study showed that there was a significant difference in the total clinical efficacy of using VitA adjuvant therapy compared to the control group without VitA [OR = 3.07, 95%CI = (2.81, 4.27)], P < 0.05. However, there was no significant difference in the adverse reaction rate between the use of VitA as an adjuvant therapy and the control without VitA [OR = 1.17, 95%CI = (0.61, 2.27)], P > 0.05. At the same time, the hospitalization time [MSD = -0.86, 95% CI = (-1.61, -0.21)], lung rale disappearance time [MSD = -0.78, 95%CI = (-1.19,-0.51)], cough duration [MSD = -1.07, 95%CI = (-1.41, -0.71)], and fever duration [MSD = -0.47, 95%CI = (-0.72, -0.23)] using VitA as an adjuvant treatment were obviously lower. In addition, the meta-analysis outcomes also showed that the use of VitA adjuvant therapy can significantly reduce IL-6 [MSD = -1.07, 95%CI = (-1.81, -0.27)] and IL-10 [MSD = -0.13, 95%CI = (-0.31, 0.12)] levels. This indicates that the application of VitA in pediatric MPP also has the effect of reducing inflammatory response. Conclusion: Based on the meta-analysis results, VitA adjuvant therapy can significantly improve the clinical symptoms of pediatric MPP patients, shorten hospitalization time, promote the disappearance of lung rales, and alleviate cough and fever symptoms. In addition, VitA adjuvant therapy can effectively reduce inflammation levels, indicating its potential role in inhibiting inflammatory responses. In clinical practice, VitA adjuvant therapy for pediatric MPP can be promoted as a potential treatment option.

2.
Environ Sci Pollut Res Int ; 31(4): 5158-5172, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38110683

ABSTRACT

In recent years, PbO2 electrodes have received widespread attention due to their high oxygen evolution reaction (OER) activity. However, due to the brittle nature of the plating layer, it is easy to cause the active layer to fall off. Pb2+ will leach out with the electrochemical process causing secondary pollution. The starting point of this study is established to improve the stability and adhesion of the electrode coating. Electrochemical oxidation technology has the characteristics of high treatment efficiency, wide range of applications, and non-polluting environment. In this study, conventional PbO2 electrodes were modified by using co-deposition of ZrO2 nanoparticles. In addition, α-PbO2 was added to increase the stability of the electrodes. At a high current density of 1 A/cm2, the accelerated life of the pure PbO2 electrode is 648 h, the accelerated life of the PbO2-ZrO2 electrode is 1.37 times that of the pure PbO2, and the electrode with an added α-PbO2 layer is 1.69 times that of the pure PbO2 electrode. The amount of dissolved Pb2+ was only 29% of that of pure PbO2. The electrochemical performance of the electrode is evaluated by studying the degradation effect of ceftriaxone sodium (CXM). The addition of ZrO2 nanoparticles alters the particle size and deposition content of PbO2, leading to a unique crystal structure distinct from pure PbO2. Compared to conventional PbO2 electrodes, the PbO2-ZrO2 can remove chemical oxygen demand (COD) and pollutants more efficiently, removing for 59% increased by 38.47%. Therefore, PbO2-ZrO2 is of great value in the field of electrochemical degradation of industrial pollutants.


Subject(s)
Nanoparticles , Water Pollutants, Chemical , Oxides/chemistry , Ceftriaxone , Lead , Water Pollutants, Chemical/analysis , Oxidation-Reduction , Electrodes , Titanium/chemistry
3.
Environ Sci Pollut Res Int ; 30(41): 94386-94400, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37531058

ABSTRACT

The goal is for governments and executives to make environmental protection and the preservation of natural resources a priority. The current research examines how green human resource management practices have altered environmental performance in China's manufacturing sector. The survey used a trustworthy and valid questionnaire adapted from the literature to obtain the data. Random sampling method has been applied to collect data from manufacturers in China's Guangdong Province. Workers in China's industrial sector are the focus of this study, and each individual is treated as a separate unit of analysis. Three hundred of the 500 questionnaires were returned with sufficient data for statistical analysis. The predicted serial mediation model was analyzed using structural equation modeling (SEM) and the PROCESS model 4. The findings revealed that green HRM practices have a major impact on environmental performance and pro-environmental actions partially mediate the relationship between GHRM and environmental performance. In addition, higher education helped moderate the effect of green HRM on environmental outcomes. In terms of environmental performance, green recruitment, green selection, and green performance, green rewards via higher education has the greatest impact (p 0.01 significance level). Through an extension of the ability-motivation-opportunity theory, this study offers useful tips for policymakers, new and current organizations, and, in particular, manufacturing enterprises, on how to implement an incentive plan to promote environmentally friendly activities and product development, which in turn will increase customer loyalty.


Subject(s)
Commerce , Government , Humans , China , Industry , Workforce
5.
Front Psychol ; 13: 1026712, 2022.
Article in English | MEDLINE | ID: mdl-36533056

ABSTRACT

COVID-19, as a crucial public health crisis, has affected our lives in nearly every aspect. Besides its major health threats, COVID-19 brings severe secondary impacts, one of which is the rise of social stigma. Although numerous studies have examined the antecedents and outcomes of COVID-19-related stigma, we still lack a systematic understanding of who is being stigmatized during the COVID-19 pandemic, what exacerbates COVID-19-related stigma, and what impacts COVID-19-related stigma has on victims. Therefore, this review aims to provide a systematic overview of COVID-19-related stigma. With 93 papers conducted with 126,371 individuals in more than 150 countries and territories spanning five continents, we identify three targets that have received the most research: Chinese/Asian people, (suspected) patients and survivors, and healthcare workers. Furthermore, we find that for each stigma target, characteristics of the stigmatized, stigmatizer, and context contribute to COVID-19-related stigma and that this stigma negatively influences victims' health and non-health outcomes. We call for future research to provide a more integrative, balanced, and rigorous picture of COVID-19-related stigma via conducting research on neglected topics (e.g., contextual factors that contribute to stigma toward HCWs) and stigma interventions and using a longitudinal design. In practice, we urge governments and institutions (e.g., ministries of public health, hospitals) to pay close attention to stigma issues and to promote safe and inclusive societies.

6.
NPJ Parkinsons Dis ; 8(1): 127, 2022 Oct 06.
Article in English | MEDLINE | ID: mdl-36202834

ABSTRACT

Uncontrolled microglial activation is pivotal to the pathogenesis of Parkinson's disease (PD), which can secrete Cathepsin L (CTSL) to affect the survival of neurons in the PD patients; however, the precise mechanism has yet to be determined. We demonstrated for the first time that CTSL was mostly released by exosomes derived from α-Syn-activated microglia, resulting in neuronal damage and death. The elevation of CTSL activity was blocked by GW4869, suggesting a critical role for exosomes in mediating CTSL release. Furthermore, the P2X7R/PI3K/AKT signalling pathway was identified as the underlying molecular mechanism since specific antagonists of this signalling pathway, P2X7R knockdown and exosome release inhibitors significantly reduced the injury to cultured mouse cortical neurons. Our study suggests that increased extracellular release of CTSL from α-Syn-activated microglia through exosomes amplifies and aggravates of the neurotoxic effect of microglia, implying that CTSL may be involved in a fresh mechanism of PD pathogenesis, and serve as a potential biomarker and a target for PD drug development.

7.
J Environ Sci (China) ; 119: 33-43, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35934463

ABSTRACT

The stronger coordination ability of mercury ions with organic ligands than the metal ions in metal organic framework (MOFs) provides an accessible way to separate mercury ions from solution using specific MOFs. In this study, a Co-based MOF (ZIF-67, Co(mIM)2) was synthesized. It did not introduce specific functional groups, such as -SH and -NH2, into its structure through complicated steps. It separate Hg2+ from wastewater with a new strategy, which utilized the stronger coordination ability of Hg2+ with the nitrogen atom on the imidazole ring of the organic ligand than the Co2+ ions. Hg2+ replaced Co2+ nodes from ZIF-67 and formed a more stable precipitate with mIM. The experimental results showed that this new strategy was efficient. ZIF-67 exhibited Hg2+ adsorption capacity of 1740 mg/g, much higher than the known MOFs sorbents. mIMs is the reaction center and ZIF-67 can improve its utilization. The sample color faded from purple to white due to the loss of cobalt ion. It is a great feature of ZIF-67 that allows users to judge whether the sorbent is deactivated intuitively. ZIF-67 can be sustainable recycled by adding organic ligands to the solution after treatment due to its simple synthesis method at room temperature. It's a high-efficient and sustainable sorbent for Hg2+ separation from wastewater.


Subject(s)
Mercury , Metal-Organic Frameworks , Water Pollutants, Chemical , Ions , Mercury/chemistry , Metal-Organic Frameworks/chemistry , Wastewater , Water Pollutants, Chemical/analysis
8.
Article in English | MEDLINE | ID: mdl-35978997

ABSTRACT

Objective. To assess the predictive worth of HPV E6/E7 mRNA detection in the outcome of the cervical low-grade squamous intraepithelial lesion (LSIL). From September 2017 to early September 2019, patients screened for high-risk HPV positive or abnormal cervical liquid-based cytology were retrospectively analyzed and diagnosed with LSIL by cervical biopsy were recruited. The independent influencing factors of the regression of LSIL lesions after follow-up were analyzed, and the outcome of LSIL was calculated. The results of the initial colposcopy in this study were CIN I, CIN II/P16-negative, CIN II/P16-positive, and CIN III. At the time of re-examination, LSIL patients had three outcomes: regression, persistence, and progression. In the two follow-ups, 330 patients were finally included, including 276 CIN I patients (group A) and 54 CIN II/P16-negative patients (group B). The positive rates of HPV E6/E7 mRNA in each group were 66.67% and 70.37% for A and B, respectively. The total positive rate of E6/E7 mRNA was 67.27%, and there was no significant difference between the two groups (P > 0.05). After 1 year follow-up, whether HPV E6/E7 mRNA regressed or was negative was associated with the outcome of LSIL-related lesions (P < 0.05). The regression or negative rate of HPV E6/E7 mRNA was 1.57 times higher than the progression rate of HPV E6/E7 mRNA-positive diagnosis of LSIL lesions. Univariate logistic regression analysis showed that age at first sexual intercourse, HPV E6/E7 mRNA results, and lesion type were statistically significant (P < 0.05). Whether HPV E6/E7 mRNA was negative (OR = 2.420, P=0.001) and age at first sexual intercourse ≥20 years (OR = 0.420, P=0.002) were independent influencing factors associated with LSIL regression. Multivariate logistic analysis showed that age of first sexual intercourse ≥20 years (OR = 0.420, P=0.002) and HPV E6/E7 mRNA-negative (OR = 2.420, P=0.001) were independent factors associated with LSIL. HPV E6/E7 mRNA detection can be used for predicting the outcome of LSIL and has a good application value.

9.
Environ Sci Pollut Res Int ; 29(59): 89156-89167, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35849232

ABSTRACT

Electrochemical advanced oxidation processes (EAOPs) is considered to be an efficacious method to degrade antibiotics. However, the performance of the anode has become the main limiting factor of this technology. In this study, due to the electron-deficient characteristics and the improvement of OER performance of Mo, we chose to use thermal decomposition to incorporate Mo into IrO2 to prepare anodes with industrial applicability. Under the optimal ratio of Ir to Mo is 7:3, (Ir0.7Mo0.3)Ox electrode's particular pore structure can expose more active sites and create a channel for the transportation of electrons, thereby promoting the formation of free radicals and degrading pollutants more efficiently. (Ir0.7Mo0.3)Ox electrode also has a higher mass activity (6.332 A g-1, three times that of the IrO2 electrode) and a larger electrochemical active area (ECSA, 375.43 cm2, seven times that of the IrO2 electrode). In addition, the optimal conditions of (Ir0.7Mo0.3)Ox electrode for degrading sulfadiazine(SDZ) were explored, which achieved a higher removal than traditional electrodes (90% removal within 4 h) when the Ti plate was the substrate. Through the intermediate products of SDZ degradation and related literatures, two possible degradation pathways of SDZ were speculated. This research provides a new type of anode catalyst for the degradation of sulfonamide antibiotics, which is possible for industrial application.


Subject(s)
Sulfadiazine , Water Pollutants, Chemical , Water Pollutants, Chemical/analysis , Electrodes , Catalysis , Oxidation-Reduction , Anti-Bacterial Agents , Titanium
10.
ACS Appl Mater Interfaces ; 14(25): 28706-28715, 2022 Jun 29.
Article in English | MEDLINE | ID: mdl-35695736

ABSTRACT

Evaluating the structural and electronic-state characteristics of long-range disordered amorphous iridium (Ir)-based oxides is still unsatisfying. Compared with the benchmark IrO2, the higher oxygen evolution reaction (OER) performance brought by IrOxOHy was normally considered to be associated with the pristine IrIII-containing species. However, such a conclusion conflicts with the opinion that high-valence metals can create excellent OER activity. To resolve such contradictions, we synthesized a pure amorphous Lu1.25IrOxOHy (Lu = lutetium) catalyst in this work. In combination with the comprehensive electrochemical evaluation in alkaline and acidic media, ex situ Ir L3-edge and O K-edge X-ray absorption spectroscopy and theoretical calculations revealed that the ultrahigh OER performance of reconstructed IrOx/Lu1.25IrOxOHy in acidic media was identified to be driven by the more d-hole-containing electronic state of IrV created by cationic vacancies. The pristine properties of IrIII-containing Lu1.25IrOxOHy conversely inhibit the OER activity in alkaline media. Additionally, the high edge-shared [IrOx]-[IrOx] motif proportion structure in amorphous Lu1.25IrOxOHy achieves a stable OER process, which exhibits a high S-number stability index similar to IrO2. We demonstrate that the key factor of the edge-shared [IrOx]-[IrOx] motif with cationic vacancies in IrVOxOHy could rationally reveal the source for most of the high-performance Ir-based materials.

11.
Environ Sci Pollut Res Int ; 29(46): 69450-69461, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35576034

ABSTRACT

Activated carbon was one of the main adsorptions utilized in elemental mercury (Hg0) removal from coal combustion flue gas. However, the high cost and low physical adsorption efficiency of activated carbon injection (ACI) limited its application. In this study, an ultra-high efficiency (nearly 100%) catalyst sorbent-Sex/Activated carbon (Sex/AC) was synthesized and applied to remove Hg0 in the simulated flue gas, which exhibited 120 times outstanding adsorption performance versus the conventional activated carbon. The Sex/AC reached 17.98 mg/g Hg0 adsorption capacity at 160 °C under the pure nitrogen atmosphere. Moreover, it maintained an excellent mercury adsorption tolerance, reaching the efficiency of Hg0 removal above 85% at the NO and SO2 conditions in a bench-scale fixed-bed reactor. Characterized by the multiple methods, including BET, XRD, XPS, kinetic and thermodynamic analysis, and the DFT calculation, we demonstrated that the ultrahigh mercury removal performance originated from the activated Se species in Sex/AC. Chemical adsorption plays a dominant role in Hg0 removal: Selenium anchored on the surface of AC would capture Hg0 in the flue gas to form an extremely stable substance-HgSe, avoiding subsequent Hg0 released. Additionally, the oxygen-containing functional groups in AC and the higher BET areas promote the conversion of Hg0 to HgO. This work provided a novel and highly efficient carbon-based sorbent -Sex/AC to capture the mercury in coal combustion flue gas. Graphical abstract Selenium-modified porous activated carbon and the interface functional group promotes the synergistic effect of physical adsorption and chemical adsorption to promote the adsorption capacity of Hg0.


Subject(s)
Air Pollutants , Mercury , Selenium , Adsorption , Air Pollutants/analysis , Charcoal/analysis , Coal/analysis , Mercury/analysis , Nitrogen/analysis , Oxygen/chemistry , Selenium/analysis
12.
Cell Biosci ; 12(1): 40, 2022 Apr 04.
Article in English | MEDLINE | ID: mdl-35379347

ABSTRACT

BACKGROUND: Human adipose-derived stem cells (hADSCs) have been demonstrated to be a promising autologous stem cell source for treating various neuronal diseases. Our study indicated that hADSCs could be induced into neuron-like cells in a stepwise manner that are characterized by the positive expression of MAP2, SYNAPSIN 1/2, NF-200, and vGLUT and electrophysiological activity. We first primed hADSCs into neuron-like cells (hADSC-NCs) and then intracerebrally transplanted them into MCAO reperfusion mice to further explore their in vivo survival, migration, integration, fate commitment and involvement in neural circuit rebuilding. RESULTS: The hADSC-NCs survived well and transformed into MAP2-positive, Iba1- or GFAP-negative cells in vivo while maintaining some proliferative ability, indicated by positive Ki67 staining after 4 weeks. hADSC-NCs could migrate to multiple brain regions, including the cortex, hippocampus, striatum, and hypothalamus, and further differentiate into mature neurons, as confirmed by action potential elicitation and postsynaptic currents. With the aid of a cell suicide system, hADSC-NCs were proven to have functionally integrated into the hippocampal memory circuit, where they contributed to spatial learning and memory rescue, as indicated by LTP improvement and subsequent GCV-induced relapse. In addition to infarction size shrinkage and movement improvement, MCAO-reperfused mice showed bidirectional immune modulation, including inhibition of the local proinflammatory factors IL-1α, IL-1ß, IL-2, MIP-1ß and promotion proinflammatory IP-10, MCP-1, and enhancement of the anti-inflammatory factors IL-15. CONCLUSION: Overall, hADSC-NCs used as an intermediate autologous cell source for treating stroke can rebuild hippocampus neuronal circuits through cell replacement.

13.
J Environ Sci (China) ; 113: 141-151, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34963524

ABSTRACT

LnMnO3+σ (Ln = La, Pr, Nd, Sm, Eu, Gd or Dy) perovskites synthesized by sol-gel method were employed for gaseous elemental mercury (Hg0) removal from coal-fired flue gas. Characterization results revealed the structure of the perovskites presented a phase transition process from rhombohedral system to O- and O'-orthorhombic structure with the change of A-site rare earth elements. The perovskites showed satisfactory Hg0 removal capacity in a narrow temperature range of 100-150°C. NdMnO3+σ with an O-O' orthorhombic structure presented the best Hg0 removal performance, which markedly depends on four factors: crystal structure, oxygen vacancy density, Mn4+/Mn3+ ratio and surface element segregation. The Hg0 removal mechanism was illustrated based on the mercury temperature programmed desorption experiment and X-ray photoelectron spectroscopy characterization. Both chemisorption and catalytic oxidation played a role in the Hg0 removal process. Chemisorption dominated the Hg0 removal, due to the slow catalytic oxidation rate at low temperature. This work preliminarily established the relation between the structure of rare earth manganese perovskite and Hg0 removal performance.


Subject(s)
Air Pollutants , Mercury , Calcium Compounds , Coal , Oxides , Temperature , Titanium
14.
Am J Transl Res ; 13(10): 11653-11661, 2021.
Article in English | MEDLINE | ID: mdl-34786091

ABSTRACT

OBJECTIVE: To explore the effectiveness of cardiac remote monitoring system (CRMS) based on artificial intelligence-enabled ECG algorithm mode for evaluating asymptomatic myocardial ischemia (AMI) in patients with coronary artery disease (CAD). METHODS: Two hundred CAD patients confirmed by coronary angiography (CA) in our hospital were included as the study subjects, 120 of whom developed myocardial ischemia (MI). All patients received 12-lead telephone remote ECG monitoring and evaluation. After monitoring, artificial intelligence-enabled ECG algorithm was performed to observe the detection rate of MI. RESULTS: Compared with artificial intelligence-enabled ECG algorithm combined with remote ECG monitoring system, the detection rate of remote ECG monitoring system in 120 MI patients was lower (96.67% vs. 86.67%, P<0.01). Among the 120 MI patients, there were 26 patients (21.67%) with symptomatic myocardial ischemia (SMI) and 94 patients (78.33%) with AMI. There was no difference between the two detection methods in the diagnosis of SMI (P>0.05), while there was a difference in the diagnosis of AMI (P<0.01). The degree and duration of ST segment decline and the threshold variability of MI were higher in SMI patients than those in AMI patients (P<0.001). It showed that the lowest frequency of MI was from 0:00 to 06:00, and the highest from 06:01 to 12:00, with significant difference compared with other time periods (P<0.05). CONCLUSION: The CRMS based on artificial intelligence-enabled ECG algorithm mode can significantly improve the detection rate of AMI. Moreover, small changes of ST segment in AMI patients and circadian rhythm of disease onset were presented.

15.
Article in Chinese | MEDLINE | ID: mdl-34628813

ABSTRACT

〓 Objective: To analyze the clinical characteristics of patients with benign paroxysmal positional vertigo, summarize experience for diagnosis and treatment activities and to explore the risk factors related to the onset of BPPV and provide reference for early intervention to reduce the risk factor exposure of BPPV. Methods:One hundred and twelve patients with BPPV were included in the study, and clinical data including age, gender, onset symptoms and duration, past medical history and family history were analyzed. A One-way ANOVA was performed on 16 variables using age, gender, diabetes, hyperuric acid, hyperlipidemia, osteoporosis, hypertension, coronary heart disease, stroke, Meniere's disease, suppurative otitis media, vestibular neuronitis, sudden deafness, head injury, ear nose/maxillofacial surgery and autoimmune thyroiditis. The statistically significant parameters of the one-way ANOVA were included in the multivariate regression analysis to explore the independent risk factors for BPPV. Results:Seventy-six cases(67.86%) of BPPV patients were primary BPPV, 36 cases(32.14%) were secondary BPPV(P<0.01). The gender composition(male, female), ears involvement(unilateral, bilateral) and semicircular canal involvement(posterior semicircular canal, horizontal semicircular canal, anterior semicircular canal, mixed type) were different between the two groups(P<0.05). During the follow-up period, 34(30.36%) patients relapsed, of which 19(25.00%) were the primary patients and 15(41.67%) were the secondary patients(P<0.01). Diabetes(P=0.004), osteoporosis(P=0.017), hypertension(P=0.013), stroke(P=0.005) and suppurative otitis media(P=0.031) were related to the onset of BPPV. Conclusion:BPPV patients are mainly primary, while the secondary patients are more likely to relapse after being cured. Diabetes, osteoporosis, hypertension, stroke and suppurative otitis media are independent risk factors for the onset of BPPV.


Subject(s)
Benign Paroxysmal Positional Vertigo , Meniere Disease , Female , Humans , Male , Neoplasm Recurrence, Local , Risk Factors , Semicircular Canals
16.
Environ Sci Pollut Res Int ; 28(46): 65487-65498, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34319516

ABSTRACT

Co3O4 is a promising Hg0 removal catalyst for industrial application. Operating temperature and low sulfur resistance are two of the main problems that hinder its industrial application in Hg0 removal. Herein, a metal-organic framework (Co-BDC) was introduced as a sacrificial template to obtain the catalyst nano-sized Co3O4@C by calcination. Part of the organic ligands is carbonized during the calcination. Carbon wrapped Co3O4 and reduced metal agglomeration. The optimal Hg0 removal temperature of the existing cobalt oxide catalysts was always around 150 °C, but H2-TPR showed that the oxygen atoms on the Co3O4@C were more active than those on Co3O4, causing the Hg0 removal temperature window of Co3O4@C to shift to lower temperatures. The Hg0 removal efficiency of Co3O4@C could reach almost 100% even at 25 °C. In the meanwhile, Co3O4@C also showed a strong SO2 resistance at ambient temperature. Experimental results and characterization proved that SO2 did not compete with Hg0 on the surface of Co3O4 at low temperatures. On the contrary, it participated in the oxidation of Hg0. This is a great improvement for Co3O4 catalyst in Hg0 removal. It reduces the restrictions on the application of Co3O4 in Hg0 removal. Co3O4@C shows considerable potential as an Hg0 removal catalyst.


Subject(s)
Mercury , Catalysis , Cobalt , Oxidation-Reduction , Oxides , Temperature
17.
ACS Appl Mater Interfaces ; 13(25): 29654-29663, 2021 Jun 30.
Article in English | MEDLINE | ID: mdl-34148341

ABSTRACT

The surface reconstruction of iridium-based derivatives (AxIryOz) was extensively demonstrated to have an excellent oxygen evolution reaction (OER) performance in an acidic medium. It is urgent to use various spectroscopy and computational methods to explore the electronic state changes in the surface reconstruction process. Herein, the underestimated Lu2Ir2O7 was synthesized and investigated. Four typical forms of electrochemistry impedance spectra involved in the reconstruction process revealed three dominating forms of reconstructed pyrochlore in the OER stage, including the inner intact pyrochlore, mid metastable [IrO6]-[IrO6] framework, and the outer collapse amorphous layer. The enhancing electron transport efficiency of the corner-shared [IrO6]-[IrO6] framework was revealed as a critical role in acidic systems. The density of state (DOS) for the constructed [IrO6]-[IrO6] framework corroborated the enhancement of Ir-O hybridization and the downshift of the d-band center. Additionally, we contrast the pristine and reconstruction properties of the Pr2Ir2O7, Eu2Ir2O7, and Lu2Ir2O7 in alkaline and acidic media. The DOS and the XANES results reveal the scale relationship between the O 2p band center and the intrinsic activity for bulk pyrochlore in alkaline media. The highest O 2p center and the highest Ir-O hybridization of Lu2Ir2O7 exhibited the best OER performance among the Ir-based pyrochlore, up to a ninefold improvement in Ir-mass activity compared to IrO2. Our findings emphasize the electrochemical behavior of the reconstruction process for activated water-splitting performance.

18.
Chem Asian J ; 16(5): 530-537, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33450118

ABSTRACT

H2 -SCR is served as the promising technology for the controlling of NOx emission, and the Pd-based derivative catalyst exhibited high NOx reduction performance. Effectively regulating the electronic configuration of the active component is favorable to the rational optimization of noble Pd. In this work, a series of Pr1-x Cex Mn1-y Pdy O3 @Ni were successfully synthesized and exhibited superior NO conversion efficiency at low temperatures. 92.7 % conversion efficiency was achieved at 200 °C over Pr0.9 Ce0.1 Mn0.9 Pd0.1 O3 @Ni in the presence of 4 % O2 with a GHSV of 32000 h-1 . Meanwhile, the outstanding performance was obtained in the resistance to SO2 (200 ppm) and H2 O (8 %). Deduced from the results of XRD, Raman, XPS, and H2 -TPR, the modification of d orbit states in palladium was confirmed originating from the incorporation in the B site of Pr0.9 Ce0.1 Mn0.9 Pd0.1 O3 . The existence of higher valence (Pd3+ and Pd4+ ) than the bivalence in Pr0.9 Ce0.1 Mn0.9 Pd0.1 O3 catalyst was evidenced by XPS analysis. Our research provides a new sight into the H2 -SCR through the higher utilization of Pd.

19.
ChemSusChem ; 14(5): 1388-1395, 2021 Mar 05.
Article in English | MEDLINE | ID: mdl-33404193

ABSTRACT

Identifying high-performance non-precious metal-based catalysts at the cathode is a major challenge for future practical applications. Herein, a soft-template route through a self-assembly arrangement of sulfur sources was successfully developed, facilitating the anion exchange. In addition, compared with pristine cobalt disulfide synthesized without templates, the cobalt disulfide prepared using the new method presented a lattice shrinking phenomenon due to the hindrance of cobalt hydroxide crystal cell. Based on X-ray absorption spectroscopy (XAS) and density functional theory (DFT) calculation, increased occupancy of eg orbitals was verified for the cobalt disulfide after shrinkage, which was the main factor for enhancing the intrinsic activity of the catalyst. Besides the microscopic morphologic structure, elementary composition, and the valence state of the elements, the possible growth process of the cobalt disulfide was also discussed in detail. As catalyst for the oxygen reduction reaction, CoS2 showed a similar half-wave potential (0.81 vs. 0.84 V for Pt/C) and higher diffusion-limiting current density (reaching 5.33 vs. 5.19 mA cm-2 for Pt/C) than a commercial Pt/C catalyst. Hence, our results provide a rational design direction for this type of catalysts.

20.
ChemSusChem ; 13(24): 6613-6620, 2020 Dec 17.
Article in English | MEDLINE | ID: mdl-33098252

ABSTRACT

Binary transition metal oxides as a promising oxygen reduction reaction (ORR) catalyst have received significant attention. However, their exact reaction mechanisms are often too complex to be discussed. Herein, novel Co-Mn composites with a well-defined nanostructure were developed for understanding the role of each component. The growth pattern of cobalt oxide and the effects of the coordination environment of Co sites during growth on the overall activity were investigated. Based on experimental and density functional theory studies, it was found that the decaying coordination number directly affected the expression of crystal planes of cobalt oxide, which further had a great influence upon limiting current density of Co-Mn catalysts. The cuboid-Co/Mn catalyst exhibited outstanding limiting current density and showed good stability, related to more highly active (110) planes exposed in Co3 O4 . These provided many references for the preparation of related nonprecious catalysts in various domains.

SELECTION OF CITATIONS
SEARCH DETAIL
...