The stabilization ability of NaA zeolite derived from fly ash for lead and cadmium in soil: Mechanisms and evaluation of effectiveness.

Developing technologies aimed at ecologically restoring is of great significance in addressing the problem of heavy metal pollution. In this study, NaA zeolites (FAZ) originated from fly ash with outstanding performance were prepared by alkali fusion hydrothermal method and used for the solidification and stabilization of heavy metals in soil. After systematic evaluation, it was found that FAZ may lower the leaching concentration of lead (Pb) in soil to <1 mg/kg and increase the stabilization rate of Pb to 80 % in the single Pb-contaminated soil, lower the leaching concentration of cadmium (Cd) in soil to <3 mg/kg and increase the stabilization rate of Cd to 60 % in the single Cd-contaminated soil, and lower the leaching concentration of Pb to 0.15 mg/kg and the leaching concentration of Cd to 0.74 mg/kg in PbCd complex polluted soil. Additionally, Pb stabilization rates reach 60 % and Cd stabilization rates reach 30 %, respectively. Ion exchange is primarily responsible for the adsorption and solidification of Pb and Cd in soil by FAZ. Generally, FAZ has a wide range of applications in the rehabilitation of contaminated soil and significantly lowers the level of heavy metal pollution in soil.

A machine learning-based diagnosis modeling of IgG4 Hashimoto's thyroiditis.

PURPOSE: This study aims to develop a non-invasive diagnosis model using machine learning (ML) for identifying high-risk IgG4 Hashimoto's thyroiditis (HT) patients. METHODS: A retrospective cohort of 93 HT patients and a prospective cohort of 179 HT patients were collected. According to the immunohistochemical and pathological results, the patients were divided into IgG4 HT group and non-IgG4 HT group. Serum TgAb IgG4 and TPOAb IgG4 were detected by ELISAs. A logistic regression model, support vector machine (SVM) and random forest (RF) were used to establish a clinical diagnosis model for IgG4 HT. RESULTS: Among these 272 patients, 40 (14.7%) were diagnosed with IgG4 HT. Patients with IgG4 HT were younger than those with non-IgG4 HT (P < 0.05). Serum levels of TgAb IgG4 and TPOAb IgG4 in IgG4 HT group were significantly higher than those in non-IgG4 HT group (P < 0.05). There were no significant differences in gender, disease duration, goiter, preoperative thyroid function status, preoperative TgAb or TPOAb levels, and thyroid ultrasound characteristics between the two groups (all P > 0.05). The accuracy, sensitivity, and specificity were 57%, 78%, and 79% for logistic regression model of IgG4 HT, 80 ± 7%, 84.7% ± 2.6%, and 75.4% ± 9.6% for the RF model and 78 ± 5%, 89.8% ± 5.7%, and 64.7% ± 5.7% for the SVM model. The RF model works better than SVM. The area under the ROC curve of RF ranged 0.87 to 0.92. CONCLUSION: A clinical diagnosis model for IgG4 HT established by RF model might help the early recognition of the high-risk patients of IgG4 HT.

Therapeutic effects of ginsenosides on osteoporosis for novel drug applications.

Osteoporosis (OP) is a metabolic bone disease with a high incidence rate worldwide. Its main features are decreased bone mass, increased bone fragility and deterioration of bone microstructure. It is caused by an imbalance between bone formation and bone resorption. Ginsenoside is a safe and effective traditional Chinese medicine (TCM) usually extracted from ginseng plants, having various therapeutic effects, of which the effect against osteoporosis has been extensively studied. We searched a total of 44 relevant articles with using keywords including osteoporosis, ginsenosides, bone mesenchymal cells, osteoblasts, osteoclasts and bone remodeling, all of which investigated the cellular mechanisms of different types of ginsenosides affecting the activity of bone remodeling by mesenchymal stem cells, osteoblasts and osteoclasts to counteract osteoporosis. This review describes the different types of ginsenosides used to treat osteoporosis from different perspectives, providing a solid theoretical basis for future clinical applications.

Chemical inertness conversion of carbon fraction in coal gangue via N-doping for efficient benzo(a)pyrene degradation.

Efficient degradation of organic pollutants in complex media via advanced oxidation processes (AOPs) is still critical and challenging. Herein, nitrogen (N)-doped coal gangue (CG) catalysts (N-CG) with economic competitiveness and environmental friendliness were successfully synthesized to activate peroxymonosulfate (PMS), exhibiting ultrafast degradation performance toward benzo(a)pyrene (BaP) with 100.00 % and 93.21 % in contaminated solution and soil under optimized condition, respectively. In addition, 0.4 N-CG possessed excellent reusability toward BaP degradation with over 80.00 % after five cycles. However, BaP removal efficiency was significantly affected by some co-existing anions (HCO3- and SO42-) and humic acid (HA) in solution and soil, as well as inhibited under alkaline conditions, especially pH ≥ 9. According to the characterizations, N-doping could promote the generation of pyridinic N and graphitic N in N-CG via high-temperature calcination, which was conducive to produce hydroxyl radical (•OH), sulfate radical (SO4•-), superoxide radical (•O2-) and single oxygen (1O2). In 0.4 N-CG/PMS system, 1O2 and •O2- were proved to be the predominant reactive oxygen species (ROSs) in BaP degradation, as well as •OH and SO4•- made certain contributions. To sum up, this work provided a promising strategy for synthesis of CG-based catalysts by chemical inertness conversion of carbon fracture via N-doping for PMS activation and opened a novel perspective for environmental remediation of hydrophobic and hydrophilic contaminants pollution.

Osteofibrous dysplasia: a narrative review.

Osteofibrous dysplasia (OFD) is a rare, benign, self-limited bone disorder with a relatively low incidence, accounting for approximately 0.2% of all primary bone tumors. It was frequently found intra-cortical of the mid-shaft of the tibia. OFD can also occur in other skeletal regions, including the fibula, ulna, radius, femur, humerus, ischium, rib, tarsus, metatarsals, vertebral, and capitate. OFD can present with asymptomatic, mass, pain, swelling, deformity, and even pathological fracture. OFD might be misdiagnosed as adamantinoma (AD) and because they are three subtypes origin from the same family of bone tumors and have similar imaging features. Moreover, pathology could provide evidence for an accurate diagnosis of OFD, but misdiagnosis may occur due to small sampling materials. To date, few studies have comprehensively introduced the epidemiology, clinical manifestations, pathogenesis, radiological features, pathology, and treatment for OFD. We herein discuss clinical signs, diagnosis methods, and treatment options of OFD to improve the understanding of OFD, which is helpful for accurate diagnosis and appropriate treatment.

Efficient benzo(a)pyrene degradation by coal gangue-based catalytic material for peroxymonosulfate activation.

A low cost and green peroxymonosulfate (PMS) activation catalyst (CG-Ca-N) was successfully prepared with coal gangue (CG), calcium chloride, and melamine as activator. Under the optimal conditions, the CG-Ca-N can remove 100 % for benzo(a)pyrene (Bap) in an aqueous solution after 20 min and 72.06 % in soil slurry medium within 60 min, which also display excellent reuse ability toward Bap after three times. The removal of Bap is significantly decreased when the initial pH value was greater than 9 and obviously inhibited in the presence of HCO3- or SO42-. The characterization results indicated that the addition of calcium chloride could stabilize and increase the content of pyridinic N during thermal annealing, resulting in the production of •OH, SO4•- and 1O2. Based on electron paramagnetic resonance (EPR) and active radical scavenging experiments, 1O2 could be identified to be the dominant role in Bap degradation. Overall, this work opened a new perspective for the low cost and green PMS catalysts and offered great promise in the practical remediation of organic pollution of groundwater and soil.

Visualization of the relationship between macrophage and wound healing from the perspective of bibliometric analysis.

Macrophages play a crucial role in aiding all phases of the wound-healing process and has garnered increasing attention recently. Although a substantial body of related studies has been published, there remains a lack of comprehensive bibliometric analysis. In this study, we collected 4296 papers from the Web of Science Core Collection database. Three tools including CiteSpace, VOSviewer and one online analytical platform were employed to conduct bibliometric analysis and data visualization. Our results revealed that the annual number of publications related to macrophage and wound healing has increased exponentially with the year. The United States and China stand as the primary driving forces within this field, collectively constituting 58.2% of the total publication output. The application of biomaterials was one of the most concerned research areas in this field. According to references analysis, the current research focus has shifted to diabetic wound healing and regulating macrophage polarization. Based on the keywords analysis, we identified the following research frontiers in the future: exosomes and other extracellular vesicles; bio-derived materials and drug delivery methods such as nanoparticles, scaffolds and hydrogels; immunomodulation and macrophage polarization in the M2-state; chronic wounds, particularly those associated with diabetes; antimicrobial peptides; and antioxidant. Additionally, TNF, IL-6, IL-10, TGF-ß1 and VEGF ranked as the five genes that have garnered the most research attention in the intersection of macrophage and wound healing. All in all, our findings offered researchers a holistic view of the ongoing progress in the field of macrophages and wound healing, serving as a valuable reference for scholars and policymakers in this domain.

Synergistic Promotion System of Montmorillonite with Cu2+ and Benzalkonium Chloride for Efficient and Broad-Spectrum Antibacterial Activity.

By intercalating montmorillonite (MMT) with Cu2+ and benzalkonium chloride (BAC), the present work constructed a synergistic promotion system (Cu2+/BAC/MMT). MMT not only enhances the thermal stability of Cu2+ and BAC but also facilitates the controlled release of Cu2+ and BAC. Concurrently, the introduction of BAC improves the material's organic compatibility. In vitro assays show that the "MIC+" of Cu2+/BAC/MMT against Staphylococcus aureus is merely 7.32 mg/L and 55.56 mg/L against Escherichia coli. At concentrations of 10 and 25 mg/L, Cu2+/BAC/MMT inactivates 100% of S. aureus and E. coli within 2 h, respectively. Furthermore, it is confirmed that the prepared Cu2+/BAC/MMT exhibits a long-term antibacterial ability through antibacterial experiments and release tests. Also, the biosafety of this material was also substantiated by in vitro cytotoxicity tests. These comprehensive findings indisputably portend that Cu2+/BAC/MMT holds promise to supplant antibiotics as an efficacious treatment modality for bacterial infections.

Corrigendum: Global research trends of ferroptosis: a rapidly evolving field with enormous potential.

[This corrects the article DOI: 10.3389/fcell.2021.646311.].

Burden of falls attributable to low bone mineral density among people aged 60 years and over in China from 1990 to 2019.

Objective: Falls in older people have become a major public health, economic and societal problem. Osteoporosis predisposes older adults to high risk of falls, which were the most common outcome attributable to low bone mineral density (LBMD). In this study, we analyze the long-term trends in falls burden attributable to LBMD among people aged 60 years and over from 1990 to 2019, using data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019 (GBD 2019). Methods: Data from GBD 2019 were used to assess the long-term trends in mortality and disability-adjusted life-year (DALY) rates by Joinpoint regression. The age-period-cohort (APC) model was used to evaluate the effects of age, period and cohort on mortality rate of falls attributable to LBMD. Results: The mortality and DALYs rates of falls attributable to LBMD among people aged 60 years and over increased from 1990 to 2019, with average annual percentage changes (AAPCs) of 1.74% (95% CI: -1.47 to 2.01%) and 0.99% (95% CI: 0.80-1.19%), respectively. APC analysis revealed that the mortality rate due to LBMD significantly increased among the older people over the age of 75 years. The risk of falls mortality due to LBMD during the period of 1990-2019 initially declined but later elevated. An overall increasing risk for falls death attributable to LBMD was presented across birth cohorts, but in cohorts born after 1930, the upward trend has slowed down. The overall net drift per year attributable to LBMD was above 0. The corresponding results showed that the negative impact of period and cohort effects among males was more pronounced than those among females. Conclusions: Falls attributable to LBMD remain an ongoing health burden in the older people in China, and the mortality has been on the rise from 1990 to 2019, especially among the older people aged 80+ years group. The prevention and treatment of LBMD should be emphasized, especially among males and oldest-old people. Furthermore, there is an urgent need to strengthen the implementation of system-wide, integrated and effective public health policies and other health interventions in China.

Posterior paramedian approach combined with a novel inverted V-shaped surgical access for intraspinal schwannomas: a retrospective case series study.

OBJECTIVE: To explore the efficacy and safety of the posterior paramedian approach combined with a novel inverted V-shaped surgical access for the treatment of intraspinal schwannomas. METHODS: This study retrospectively reviewed consecutive patients who underwent surgical resection of the intraspinal schwannomas via the inverted V-shaped approach at our center between January 2016 and May 2021. Changes between the preoperative and postoperative visual analog scale (VAS) scores and neurological function Japan Orthopaedic Association (JOA) scores were assessed. Secondary outcomes such as success rate of tumor resection, operation time, blood loss, spinal stability, and disruption degree of intervertebral joints. Postoperative complications were also investigated. RESULTS: Of these 36 consecutive patients, there were 6 cases in the cervical spine, 2 cases at the cervical-thoracic junction, 11 cases in the thoracic spine, 4 cases at the thoracic-lumbar junction and 13 cases in the lumbar spine. The average operation time was 99 min, and the average blood loss was 95.4 mL. The tumor removal rate was 100%. Postoperative CT re-examination showed that the spinous processes were intact in all cases, the facet joint surfaces were intact in 32 cases. At the time of last follow-up, the median JOA score was 25 (9-27), which was significantly improved compared to the preoperative median JOA score of 15 (10-22) (P < 0.01). The overall excellent and good rate were 88.9 %. The median VAS score at post-surgery was 0 (0-2), which was significantly improved compared to the preoperative median VAS score of 4 (2-8) (P < 0.01). As for complications, there were no cases of cerebrospinal fluid leakage or spinal instability. Three patients who had a postoperative fever finally recovered after lumbar cistern drainage. CONCLUSION: The inverted V-shaped surgical access via the posterior paramedian approach is an effective and safe method for the treatment of intraspinal schwannomas.

Complete perforated bladder from intrauterine devices: A case series report from a nationwide monitoring system.

AIM: Complete perforation of the bladder caused by an intrauterine device (IUD) is rare. This study examined the characteristics of patients associated with IUD-related bladder perforation and evaluated the relationship between mislocated IUDs and their potential complications. METHODS: From October 2005 to December 2021, 13 reports regarding complete perforations to the bladder by IUDs were retrieved from the National Contraceptives Adverse Reaction Monitoring System of China. The clinical features of these cases were analyzed. RESULTS: The median patient age was 30 (range, 27-46) years. There were four cases (4/13, 30.8%) with IUDs placed during lactation, one case (1/13, 7.7%) with an IUD placed after medical abortion, and eight cases (8/13, 61.5%) placed after menstruation. Seven cases (7/13, 53.9%) were first-time IUD users. The median duration of IUD placement was 47 (range, 1-145) months. Unexpected pregnancy was reported in five cases (5/13, 38.5%). Six cases (6/13, 46.2%) reported bladder stones with varying degrees of abdominal pain or urinary tract infection. Removal methods included laparotomy (four cases), cystoscopy (four cases), laparoscopy (two cases), laparoscopy combined with cystoscopy (two cases), and laparotomy after cystoscopy (one case). All IUDs were successfully removed. CONCLUSIONS: Complete perforation to the bladder by IUDs is a rare adverse event. Regular follow-up is required after the placement of IUDs. The possibility of uterine perforation should be investigated if IUD users encounter persistent lower abdominal pain or urinary tract infection.

Comprehensive analysis of the cuproptosis-related gene DLD across cancers: A potential prognostic and immunotherapeutic target.

DLD is a key gene involved in "cuproptosis," but its roles in tumor progression and immunity remain unclear. Exploring the potential mechanisms and biological roles of DLD may provide new insights for therapeutic strategies for tumors. In the present study, we analyzed the role of DLD in a variety of tumors by using several bioinformatic tools. The results showed that compared with normal tissues, tumor tissues representing multiple cancers showed significant differential expression of DLD. High DLD expression was associated with a good prognosis in BRCA, KICH, and LUAD. Conversely, high expression levels of DLD were detrimental to patient prognosis in many other tumors, such as COAD, KIRC, and KIRP. In addition, the associations of DLD with infiltrating immune cells, genetic alterations and methylation levels across cancers were assessed. Aberrant expression of DLD was positively correlated with most infiltrating immune cells, especially neutrophils. The DLD methylation level was significantly decreased in COAD, LIHC, and LUSC but significantly increased in BRCA. DLD had the highest mutation rate (6.04%) in ESCA. In LUSC, patients with genetic alterations in DLD showed a poorer prognosis. At the single-cell level, the roles of DLD in regulating cancer-associated biological functions, such as metastasis, inflammation, and differentiation, were explored. Afterward, we further investigated whether several disease-associated genes could be correlated with DLD. GO enrichment analysis indicated that DLD-related genes were mainly associated with mitochondria-related cellular components, aerobic respiration and the tricarboxylic acid cycle. Finally, the correlations between DLD expression and immunomodulatory genes, immune checkpoints, and sensitivity to some antitumor drugs were investigated. It is worth noting that DLD expression was positively correlated with immune checkpoint genes and immunomodulatory genes in most cancers. In conclusion, this study comprehensively analyzed the differential expression, prognostic value and immune cell infiltration-related function of DLD across cancers. Our results suggest that DLD has great potential to serve as a candidate marker for pancancer prognosis and immunotherapy and may provide a new direction for cancer treatment development.

Global research characteristics and trends of infection after spinal implant surgery: a bibliometric analysis.

Background: With the growing awareness of postoperative infection, increasing focus has been placed on infection after spinal implant surgery (IASIS). This study aimed to explore the development and trends of research regarding IASIS using bibliometric analysis. Methods: Scientific articles on IASIS research published between February 1, 2000, and December 31, 2020 were retrieved from the Web of Science database. Results: A total of 820 publications were included in the bibliometric analysis, with studies originating from 46 countries and 6 languages. Researchers from the United States published the highest number of articles and collaborated closely with researchers in Canada, Germany, and Japan. The author with the most publications was Alexander R. Vaccaro. The journal with the most articles and citations was Spine. Most of the research was performed on risk factors and the incidence of IASIS. Co-occurrence analysis revealed that the most recent research trend was likely related to the management of IASIS and the international consensus meeting. Three clusters of research were identified through a thematic map: diagnosis and treatment of IASIS, scoliosis-related infection, and risk factors and prevention of IASIS. Conclusions: Research on IASIS increasingly grew between 2000 and 2020. Spinal surgeons and institutes from the United States had the highest number of publications and academic impact in this field. Diagnosis-related problems and multidisciplinary work on IASIS require further attention in the future. Current trends in IASIS are likely associated with IASIS management and the international consensus meeting.

Morphology regulation of zero-valent iron nanosheets supported on microsilica for promoting peroxymonosulfate activation.

Combing the assisted dispersion strategy of support with the wet chemical reduction method, a novel nano-zero valent iron/microsilica (nZVI/M) composite was successfully fabricated, where the 2D nZVI nanosheets were uniformly anchored and covered on the surface of microsilica. The introduction of microsilica notably relieved the agglomeration effect of nZVI nanosheets, which induced the improvement of specific surface area (45.68 m2/g) and pore volume (0.172 cm3/g), and thereby exposing more active sites for bisphenol A (BPA) removal. The optimized nZVI/M-0.6 displayed the superior catalytic performance in the presence of peroxymonosulfate (PMS) with the degradation rate of BPA reached above 97% within 3 min and a higher constant rate of 0.659 min-1, which was approximately 3.9 times as high as that of nZVI/PMS system. The homogeneously dispersion of nZVI nanosheets on microsilica benefited for the assembly of the pollutants and boosting the kinetics of the catalytic degradation process. As a highly efficient PMS activator, it could well maintain the catalytic activity in different real water samples. The quenching experiments verified that SO4•- played the dominate role for BPA removal. This work offered novel insights for designing and preparing iron-based persulfate activator for wastewater treatment.

Defect Engineering Modulated Iron Single Atoms with Assist of Layered Clay for Enhanced Advanced Oxidation Processes.

Single-atom catalysts (SACs) feature maximum atomic utilization efficiency; however, the loading amount, dispersibility, synthesis cost, and regulation of the electronic structure are factors that need to be considered in water treatment. In this study, kaolinite, a natural layered clay mineral, is applied as the support for g-C3 N4 and single Fe atoms (FeSA-NGK). The FeSA-NGK composite exhibits an impressive degradation performance toward the target pollutant (>98% degradation rate in 10 min), and catalytic stability across consecutive runs (90% reactivity maintained after three runs in a fluidized-bed catalytic unit) under peroxymonosulfate (PMS)/visible light (Vis) synergetic system. The introduction of kaolinite promotes the loading amount of single Fe atoms (2.57 wt.%), which is a 14.2% increase compared to using a bare catalyst without kaolinite, and improved the concentration of N vacancies, thereby optimizing the regulation of the electronic structure of the single Fe atoms. It is discovered that the single Fe atoms successfully occupied five coordinated N atoms and combined with a neighboring N vacancy. Consequently, this regulated the local electronic structure of single Fe atoms, which drives the electrons of N atoms to accumulate on the Fe centers. This study opens an avenue for the design of clay-based SACs for water purification.

A cuproptosis-related genes signature associated with prognosis and immune cell infiltration in osteosarcoma.

Osteosarcoma (OS) is one of the most prevalent primary bone tumors at all ages of human development. The objective of our study was to develop a model of Cuproptosis-Related Genes (CRGs) for predicting prognosis in OS patients. All datasets of OS patients were obtained from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database and Gene Expression Omnibus (GEO) database. We obtained the gene set (81 CRGs) related to cuproptosis by accessing the database and previous literature. All the CRGs were analyzed by univariate COX regression, least absolute shrinkage and selection operator (LASSO) COX regression analysis to screen for CRGs associated with prognosis in OS patients. Then these CRGs were used to construct a prognostic signature, which was further verified by independent cohort (GSE21257) and clinical correlation analysis. Afterward, to identify underlying mechanisms, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used for the high-risk group by using the GSEA method. The association between the prognostic signature and 28 types of immune infiltrating cells in the tumor microenvironment was assessed. Ultimately, Lipoic Acid Synthetase (LIAS) (HR=0.632, P=0.004), Lipoyltransferase 1 (LIPT1) (HR=0.524, P=0.011), BCL2 Like 1 (BCL2L1/BCL-XL) (HR=0.593, P=0.022), and Pyruvate Dehydrogenase Kinase 1 (PDK1) (HR=0.662, P=0.025) were identified. Subsequently, they were used to calculate the risk score and build a prognostic model. In the training cohort, risk score (HR=1.878, P=0.003) could be considered as an independent prognostic factor, and OS patients with high-risk scores showed lower survival rates. Biological pathways related to substance metabolism and transport were enriched. There were significant differences in immune infiltrating cells in the tumor microenvironment. All in all, The CRGs signature is related to the tumor immune microenvironment and could be used as a credible predictor of the prognostic status in OS patients.

Factors Associated With HIV Testing Among MSM in Guilin, China: Results From a Cross-Sectional Study.

Objectives: The objective of this study is to explore factors affecting the HIV testing behaviors among men who have sex with men (MSM) in China. Methods: A cross-sectional study was conducted in Guilin, China from April to June of 2021. Questionnaire data of 300 MSM were analyzed, and binary logistic regression models were used to examine the socio-demographic and sexual behavior characteristics associated with three HIV testing behaviors (self-testing, institutional testing, and regular testing). Results: The results showed that half of the respondents had the habit of regular HIV testing. Only 30.0% of MSM chose to do HIV testing after high-risk sexual behavior, and self-perceived luck was the main reason for not having HIV testing. Moreover, the influencing factors of three HIV testing behaviors after high-risk sexual behavior differ. Interestingly, income was not related to any of the three HIV testing behaviors among those MSM who participated. Conclusion: This research indicates insufficient health education on HIV testing behaviors among MSM in China. Health promotion practices targeting the MSM population to improve HIV-related knowledge, thus contributing to the HIV epidemic, are required.

Natural Diatomite Supported Zirconium-Doped TiO2 with Tailoring Band Structure for Enhanced Visible-Light Photocatalytic Properties.

The development of economically applicable, highly efficient and low cost photocatalytic materials has always been a challenge. In this work, we report a zirconium doped TiO2/diatomite (ZrTD) composite with enhanced visible light-induced photocatalytic activity. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, UV-VIS diffused reflectance spectroscopy, high-performance liquid chromatography-mass spectrometry, photoluminescence and X-ray photoelectron spectroscopy, respectively. The optimal doping ratio of zirconium into TiO2 was obtained at 3% (3%ZrTD composite), and the degradation rate constant of which tetracycline (TC) is up to around 8.65 times higher that of zirconium doped TiO2. In addition, zirconium doping introduces the impurity levels of Zr 3d and oxygen vacancies into the lattice of TiO2, resulting in broadening the light absorption range, reducing the band gap, and improving the separation efficiency of photogenerated electron-hole pairs, thus endowing with visible light photocatalytic properties. Moreover, both the photogenerated holes (h+) and superoxide (•O2-) radicals are responsible for the degradation process of TC, and a possible degradation pathway and the corresponding intermediate products of TC by ZrTD composite are also proposed in detail.

Efficient peroxymonosulfate activation of immobilized Fe-N-C catalyst on ceramsite for the continuous flow removal of phenol.

Nowadays, developing environmentally friendly catalysts with both low cost and high efficiency was still a challenge in actual organic wastewater purification. Herein, the Fe-N-C catalyst was successfully immobilized on solid waste derived ceramsite for efficient degradation of phenol under continuous flow conditions by activating peroxymonosulfate (PMS). After the introduction of ceramsite, the microstructure of Fe-N-C catalyst was changed from granular structure to worm-like structure, promoting the dispersion of the nanoscale catalyst and providing more reactive sites. Therefore, the phenol removal rate and mineralization rate of the obtained 0.5FNNC within 30 min were up to 96.79% and 71.79%, respectively. In addition, the degradation rate of the optimal composite (0.5FNNC)/PMS system was about 4.06 times higher than that of bare Fe-N-C/PMS system. Intriguingly, the Fe ion leaching from 0.5FNNC during the degradation reaction was significantly lower than bare Fe-N-C owing to the strong catalyst-support chemical bonding. Based on electron paramagnetic resonance, quenching experiments, X-ray photoelectron spectroscopy analysis and electrochemical analysis, it was indicated that the non-radical processes (1O2 and high valent iron-oxo species) should be responsible for the phenol degradation. Meanwhile, the possible phenol degradation pathways were proposed, and the intermediates were evaluated for ecotoxicity by ECOSAR. Finally, a preliminary economic analysis of this process was carried out. Overall, this work would provide a new strategy for the construction of ceramsite based multi-pore composite catalysts and the large-scale application of persulfate oxidation technology in organic wastewater treatment.