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1.
Aging (Albany NY) ; 132021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33612480

RESUMO

The interplay between microbiota and host metabolism plays an important role in health. Here, we examined the relationship between age, gut microbiome and host serum metabolites in male C57BL/6J mice. Fecal microbiome analysis of 3, 6, 18, and 28 months (M) old mice showed that the Firmicutes/Bacteroidetes ratio was highest in the 6M group; the decrease of Firmicutes in the older age groups suggests a reduced capacity of gut microflora to harvest energy from food. We found age-dependent increase in Proteobacteria, which may lead to altered mucus structure more susceptible to bacteria penetration and ultimately increased intestinal inflammation. Metabolomic profiling of polar serum metabolites at fed state in 3, 12, 18 and 28M mice revealed age-associated changes in metabolic cascades involved in tryptophan, purine, amino acids, and nicotinamide metabolism. Correlation analyses showed that nicotinamide decreased with age, while allantoin and guanosine, metabolites in purine metabolism, increased with age. Notably, tryptophan and its microbially derived compounds indole and indole-3-lactic acid significantly decreased with age, while kynurenine increased with age. Together, these results suggest a significant interplay between bacterial and host metabolism, and gut dysbiosis and altered microbial metabolism contribute to aging.

2.
Clin Transplant ; : e14238, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33527545

RESUMO

OBJECTIVE: The objective of this study was to assess how pre-transplant dialysis duration affects transplant outcomes after simultaneous pancreas-kidney transplant (SPK) in patients with type 1 diabetes mellitus (T1DM). METHODS: Data of 6887 T1DM patients who underwent SPK transplantation between 2008 and 2018 were obtained from the Scientific Registry of Transplant Recipients database. According to pre-transplant dialysis duration, the patients were divided into the preemptive SPK, 0-2 years, 2-5 years, and >5 years dialysis groups. Kaplan-Meier survival analysis was performed to compare patient and graft survival among the groups. Univariate and multivariate Cox regression analyses were used to identify predictors of transplant outcomes. RESULTS: The mean follow-up period was 56.7 ± 34.7 months. Compared with no dialysis or preemptive SPK, dialysis for 0-2 years was not significantly associated with patient or kidney graft survival, while long-term dialysis of 2-5 years and >5 years was significantly associated with increased risk of death and kidney graft failure. However, the duration of dialysis was not associated with pancreas graft survival. CONCLUSION: Long-term dialysis duration before SPK transplant is an independent predictor of patient death and kidney graft failure in T1DM patients.

3.
Ann Palliat Med ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33548993

RESUMO

BACKGROUND: To determine the efficacy and safety of anti-angiogenic drugs combined with erlotinib in the treatment of advanced non-small cell lung cancer (NSCLC), we performed a meta-analysis of 10 randomized controlled trials (RCTs). METHODS: An electronic literature search of PubMed, Cochrane Library, Embase, and other databases was performed. Literature was retrieved on December 2, 2019. We collected and compared RCTs on antiangiogenic drugs combined with erlotinib (A + E) for NSCLC, and analyzed outcomes including overall survival (OS), objective response rate (ORR), progression-free survival (PFS), and incidence of severe adverse events (grade ≥3 AEs). RESULTS: Compared with the control group, combined treatment did not increase the ORR (RR 1.03, 95% CI: 0.95-1.11, P=0.52) or prolong OS (HR 1.03, 95% CI: 0.91-1.17, P=0.24); however, a significant improvement was seen in PFS (HR 0.63, 95% CI: 0.57-0.70, P<0.001). The subgroup analysis showed that patients with epidermal growth factor receptor (EGFR) mutations and patients with adenocarcinoma could benefit from combination therapy, as could those from Asian populations. Although combination therapy was found to carry an increased incidence of grade 3 or higher adverse events including diarrhea and proteinuria, these remained within controllable levels. CONCLUSIONS: Anti-angiogenic drugs used in combination with erlotinib can significantly prolong PFS in patients with advanced NSCLC.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33550809

RESUMO

Finding highly efficient and reusable catalysts for advanced oxidation processes is a crucial endeavor to resolve the severe water pollution problems. Although numerous nanocatalysts have been developed in the past few decades, their recyclability along with sustainably high catalytic efficiency still remain challenging. Here, we propose a new strategy for designing efficient and reusable catalysts, that is, introducing Cu as a reductant into a metallic glass-based catalyst and constructing three-dimensional hierarchical porous architectures via a laser 3D printing technique. The as-printed 3D porous MG/Cu catalysts exhibit exceptional catalytic efficiency in degrading RhB with a normalized rate constant approximately 620 times higher than commercial nano zero-valent iron, outperforming most reported Fenton-type catalysts so far. Strikingly, the catalysts exhibit an excellent reusability and can be used more than 100 times (the highest record so far) without apparent efficiency decay. It is revealed that Cu-doping could improve the surface reducibility and promote the electronic transfer, rendering the 3D-printed MG/Cu catalysts with a sustainably active Fe(II)-rich surface and, therefore, unprecedented reusability. This work offers a broadly applicable design route for the development of advanced catalysts with an outstanding combination of activity and reusability for wastewater treatments.

5.
Small ; : e2006599, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33522150

RESUMO

Invoking the occurrence of pyroptosis is an emerging strategy for the treatment of cancer. However, the practical applications of pyroptosis for cancer therapy are currently hindered due to the lack of tumor-specific and efficient pyroptotic agents in vivo. Herein, a virus-spike tumor-activatable pyroptotic agent (VTPA) for cancer-specific therapy is reported. The VTPA is composed of an organosilica coated iron oxide nanoparticle core and spiky manganese dioxide protrusions, which can readily accumulate in tumor after systemic administration, facilitate the tumor intracellular lysosomal rupture, and be degraded by tumor over-expressed intracellular glutathione (GSH) to release Mn ions and iron oxide nanoparticles (IONPs) for the synergetic activation of nucleotide binding oligomerization domain-like receptors protein 3 (NLRP3) inflammasomes. Consequently, the activation of NLRP3 inflammasomes and the release of lactate dehydrogenase of tumor cells are observed after the treatment of VTPA, resulting in a specific pyroptotic cell death. To our best knowledge, the structure-dependent and tumor intracellular GSH activatable pyroptotic agents represent the first demonstration of cancer-specific pyroptosis in vivo, providing a novel paradigm for the development of next-generation cancer-specific pyroptotic nanomedicine.

6.
Sci Adv ; 7(2)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33523996

RESUMO

Circadian clocks create a 24-hour temporal structure, which allows organisms to occupy a niche formed by time rather than space. They are pervasive throughout nature, yet they remain unexpectedly unexplored and uncharacterized in nonphotosynthetic bacteria. Here, we identify in Bacillus subtilis circadian rhythms sharing the canonical properties of circadian clocks: free-running period, entrainment, and temperature compensation. We show that gene expression in B. subtilis can be synchronized in 24-hour light or temperature cycles and exhibit phase-specific characteristics of entrainment. Upon release to constant dark and temperature conditions, bacterial biofilm populations have temperature-compensated free-running oscillations with a period close to 24 hours. Our work opens the field of circadian clocks in the free-living, nonphotosynthetic prokaryotes, bringing considerable potential for impact upon biomedicine, ecology, and industrial processes.

7.
Technol Cancer Res Treat ; 20: 1533033821990064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33596783

RESUMO

BACKGROUND: Bone metastasis is a leading cause of the high mortality rate of prostate cancer (PCa), but curative strategies remain lacking. Recent studies suggest long non-coding RNAs (lncRNAs) may be potential targets to develop drugs. However, PCa bone metastasis-specifically-related lncRNAs were rarely reported. This study aimed to identify crucial lncRNAs and reveal their function mechanisms. METHODS: GSE32269 and GSE26964 microarray datasets, downloaded from the Gene Expression Omnibus database, were used to analyze differentially expressed genes (DEGs)/lncRNAs (DELs) and miRNAs (DEMs), respectively. Weighted gene co-expression network analysis was performed to screen PCa bone metastasis-associated modules. The co-expression and competing endogenous RNAs (ceRNAs) networks were constructed to identify hub lncRNAs. Univariate Cox regression analysis was conducted to determine their prognostic values. The correlation of lncRNAs with immune infiltrating cells was analyzed by using Tumor IMmune Estimation Resource. Therapeutic drugs were predicted by querying the Connectivity Map (CMap) and the Comparative Toxicogenomics Database (CTD). RESULTS: A total of 18 DELs, 2,614 DEGs and 86 DEMs were screened between bone metastatic and primary PCa samples. Four modules enriched by DEGs were shown to be bone metastasis-associated. LncRNA HCG18 and MCM3AP-AS1 were identified to be important because they existed in both of the co-expression and ceRNA networks (forming the relationship pairs: HCG18/MCM3AP-AS1-KNTC1, MCM3AP-AS1-hsa-miR-508-3p-DTL and HCG18/MCM3AP-AS1-hsa-miR-127-3p-CDKN3). All the genes in these interaction pairs were significantly associated with overall survival of PCa patients. Also, HCG18, MCM3AP-AS1 and their target mRNAs were positively correlated with various tumor-infiltrated immune cells, especially increased M2 macrophages. Valproic acid and trichostatin A may be effective to treat PCa bone metastasis by targeting HCG18 and MCM3AP-AS1. CONCLUSION: HCG18 and MCM3AP-AS1 that regulate M2 macrophage infiltration may be important targets to treat PCa bone metastasis and improve prognosis.

8.
Sci Adv ; 7(5)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33571116

RESUMO

Antibiotic resistance is now a major threat to human health, and one approach to combating this threat is to develop resistance-resistant antibiotics. Synthetic antimicrobial polymers are generally resistance resistant, having good activity with low resistance rates but usually with low therapeutic indices. Here, we report our solution to this problem by introducing dual-selective mechanisms of action to a short amidine-rich polymer, which can simultaneously disrupt bacterial membranes and bind to bacterial DNA. The oligoamidine shows unobservable resistance generation but high therapeutic indices against many bacterial types, such as ESKAPE strains and clinical isolates resistant to multiple drugs, including colistin. The oligomer exhibited excellent effectiveness in various model systems, killing extracellular or intracellular bacteria in the presence of mammalian cells, removing all bacteria from Caenorhabditis elegans, and rescuing mice with severe infections. This "dual mechanisms of action" approach may be a general strategy for future development of antimicrobial polymers.

9.
J Craniofac Surg ; 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33587526

RESUMO

OBJECTIVE: To explore the preliminary application of three-dimensional (3D) printing technique in preoperative localization of meningiomas in primary hospitals. PATIENTS AND METHODS: The enrolled subjects were 13 patients in the Department of Neurosurgery, Affiliated Hospital of Binzhou Medical College, Shandong Province between December 2018 and June 2020, including CT or MRI data from eight cases of brain meningiomas and five cases of cerebrospinal meningiomas. The Mimics 17.0 software package was applied to reconstruct the 3D images and print out the 3D guide. The authors placed the 3D printed guide on the surgical area for preoperative tumor location. RESULTS: The 3D printed guides for all patients were successfully designed and printed out. Simpson grade I resection was performed on all tumors. No significant hematoma, brain edema, or neurological symptoms were observed in the postoperative patients, and the surgical results were good. CONCLUSIONS: The authors can use 3D printing technology for precise preoperative localization of meningiomas. Grassroots hospitals can also use this technique because of its economic, accurate, and personalized characteristics.

10.
Inorg Chem ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33591755

RESUMO

Oxygen evolution reaction (OER) is a principal process in electrochemical energy conversion. Unfortunately, the sluggish reaction kinetics of OER hinders large-scale applications of those electrochemical energy conversion technologies. In this article, nickel-based metal-organic framework nanosheets attached on carbon nanotube films were successfully synthesized. The self-supporting electrode exhibits a fascinating activity with an overpotential of 221 mV at a current density of 10 mA cm-2 and long-term stability with 24 h without noticeable changes of current density. In situ Fourier transform infrared testing reveals the formation of the key active intermediates (HO*, O*, and HOO*) during the OER process. A series of material characterization demonstrated that coordinatively unsaturated metal sites on the Ni-BDC are the real active sites in OER.

11.
Oral Radiol ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560504

RESUMO

INTRODUCTION: Few studies have compared the relationship of MSV in the different craniofacial patterns. Hence, the purpose of this research was to evaluate maxillary sinus volume in different craniofacial patterns using cone-beam computed tomography. MATERIALS AND METHODS: This cross-sectional study included 100 pre-orthodontic patients mean aged 26.40 ± 6.77 (age ranged 21-64) years divided into different anteroposterior and vertical skeletal groups. From the cone beam computed tomography images using MIMICS 14.1 software, three-dimensional image of the maxillary sinus was constructed, and its volume was calculated. RESULTS: The mean maxillary sinus volume was 20,279.50 ± 7800.33 mm3. Among the anteroposterior skeletal groups, the mean maxillary sinus volume in skeletal Class II group is significantly larger than class III group (P < 0.05). Among the vertical skeletal groups, High-angle groups tend to have the largest maxillary sinus volume, though there were no significant differences among the groups (P > 0.05). Similarly, males have significantly larger maxillary sinus volume than females (P < 0.05). There was a positive correlation between ANB and maxillary sinus volume (P < 0.01). CONCLUSION: Maxillary sinus volume is significantly larger in skeletal class II than in skeletal class III group and in males than in females (P < 0.05). These inferences have several implications in orthodontics, endodontics and oral surgery.

12.
Biomed Pharmacother ; 135: 111183, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401222

RESUMO

BACKGROUND: Our previous studies found that Pure total flavnoids from citrus (PTFC) can effectively improve non-alcoholic steatohepatitis (NASH) in mice. Here, we discuss on the mechanism of PTFC in treating NASH with focus on the regulation of the gut microbiota and bile acid metabolism. METHODS: C57BL/6 J mice were randomly divided into three groups: normal diet group (Normal), high-fat diet group (HFD) and high-fat + PTFC treatment group (PTFC). Mice in the Normal group were fed chow diet, while the other groups were fed high fat diet (HFD) for 16 weeks. In the 5th week, the mice in the PTFC group were treated with 50 mg/kg/day PTFC for an additional twelve weeks. After sacrifice, histopathology of the liver was assessed, and the gut microbial composition was analyzed by 16S rDNA gene sequencing. Bile Acid profiles in serum were determined by ultraperformance liquid chromatography (UPLC-MS/MS). RESULTS: PTFC intervention significantly attenuated HFD-induced NASH symptoms compared with the HFD group in mice. 16S rDNA sequencing showed that PTFC treatment increased the phylogenetic diversity of the HFD-induced microbiota dysbiosis. PTFC intervention significantly increased the relative abundances of Bacteroidaceae and Christensenellaceae. Furthermore, PTFC reduced the content of toxic bile acids, such as TDCA, DCA, TCA, CA and increased the ratio of secondary to primary bile acids. FXR and TGR5 deficiency were significantly alleviated. CONCLUSION: PTFC can improve NASH via the the gut microbiota and bile acid metabolism.

13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 37(2): 119-124, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33504417

RESUMO

Objective To explore whether oncolytic adenovirus expressing CCL19 can inhibit the growth of gastric cancer cells and activate anti-tumor immune response. Methods Mouse CCL19 gene was inserted into the E3 region of oncolytic adenovirus Ad5 to obtain engineered oncolytic adenovirus Ad5-CCL19. The expression of CCL19 in Ad5-CCL19-infected mouse MFC cells was detected by Western blotting. The effects of Ad5-CCL19 on the proliferation of MFC cells, MGC803 cells and BGC823 cells were tested by MTT assay. The anti-tumor activity of Ad5-CCL19 in vivo was examined by MFC cell subcutaneous transplantation tumor model. Immunofluorescence histochemical staining was used to detect CD4 and CD8 expression in tumor tissue. The secretion levels of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in tumor infiltrating T cells were detected by flow cytometry. Results Ad5-CCL19 could effectively infect MFC cells to secrete CCL19. Also, Ad5-CCL19 could induce significant dose-dependent cytotoxicity against target cells in vitro. The experiment in vivo showed that Ad5-CCL19 had stronger inhibitory effects on MFC cell tumor than Ad5 in the mice, and it could effectively enhance the infiltration of CD4+ T cells and CD8+ T cells and increase the secretion of IFN-γ and TNF-α in tumor tissues. Conclusion Ad5-CCL19 can significantly infect MFC gastric cancer cells to inhibit their growth and improve the anti-tumor immune activity of the tumor site.


Assuntos
Terapia Viral Oncolítica , Neoplasias Gástricas , Adenoviridae/genética , Animais , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Quimiocina CCL19 , Imunidade , Camundongos , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia
14.
Sheng Wu Gong Cheng Xue Bao ; 37(1): 1-14, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33501785

RESUMO

Microbial fuel cell (MFC) is a bioelectrochemical device, that enables simultaneous wastewater treatment and energy generation. However, a few issues such as low output power, high ohmic internal resistance, and long start-up time greatly limit MFCs' applications. MFC anode is the carrier of microbial attachment, and plays a key role in the generation and transmission of electrons. High-quality bioelectrodes have developed into an effective way to improve MFC performance. Conjugated polymers have advantages of low cost, high conductivity, chemical stability and good biocompatibility. The use of conjugated polymers to modify bioelectrodes can achieve a large specific surface area and shorten the charge transfer path, thereby achieving efficient biological electrochemical performance. In addition, bacteria can be coated with nano-scale conjugated polymer and effectively transfer the electrons generated by cells to electrodes. This article reviews the recently reported applications of conjugated polymers in microbial fuel cells, focusing on the MFC anode materials modified by conjugated polymers. This review also systematically analyzes the advantages and limitations of conjugated polymers, and how these composite hybrid bioelectrodes solve practical issues such as low energy output, high inner resistance, and long starting time.


Assuntos
Fontes de Energia Bioelétrica , Purificação da Água , Bactérias , Eletricidade , Eletrodos , Polímeros
15.
Nanoscale ; 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33508048

RESUMO

Nickel (Ni)-rich layered oxides such as LiNi0.6Co0.2Mn0.2O2 (NCM622) represent one of the most promising candidates for next-generation high-energy lithium-ion batteries (LIBs). However, the pristine Ni-rich cathode materials usually suffer from poor structural stability during cycling. In this work, we demonstrate a simple but effective approach to improve the cycling stability of the NCM622 cathode by dry coating of ultrastable Li3V2(PO4)3-carbon (LVP-C) nanoparticles, which leads to a robust composite cathode (NCM622/LVP-C) without sacrificing the specific energy density compared with pristine NCM622. The optimal NCM622/LVP-C composite presents a high specific capacity of 162 mA h g-1 at 0.5 C and excellent cycling performance with 85.0% capacity retention after 200 cycles at 2 C, higher than that of the pristine NCM622 (67.6%). Systematic characterization confirms that the LVP-C protective layer can effectively reduce the side reactions, restrict the cation mixing of NCM622 and improve its structural stability. Moreover, the NCM622/LVP-C||graphite full cells also show a commercial-level capacity of 3.2 mA h cm-2 and much improved cycling stability compared with NCM622/LVP-C||graphite full cells, indicating the great promise for low-cost, high-capacity and long-life LIBs.

16.
Phys Rev Lett ; 126(2): 026802, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512194

RESUMO

We report on the observation of a T_{c}∼0.9 K superconductivity at the interface between LaAlO_{3} film and the 5d transition metal oxide KTaO_{3}(110) single crystal. The interface shows a large anisotropy of the upper critical field, and its superconducting transition is consistent with a Berezinskii-Kosterlitz-Thouless transition. Both facts suggest that the superconductivity is two-dimensional (2D) in nature. The carrier density measured at 5 K is ∼7×10^{13} cm^{-2}. The superconducting layer thickness and coherence length are estimated to be ∼8 and ∼30 nm, respectively. Our result provides a new platform for the study of 2D superconductivity at oxide interfaces.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33420833

RESUMO

PURPOSE: Esophagojejunostomy is a challenging step in laparoscopic gastrectomy. Although the overlap method is a safe and feasible approach for esophagojejunostomy, it has several technical limitations. We developed novel modifications for the overlap method to overcome these disadvantages. METHODS: Forty-eight consecutive gastric cancer patients underwent totally laparoscopic total gastrectomy or laparoscopic proximal gastrectomy with double-tract reconstruction at our institution from January 2019 to April 2020 using the overlap method with the following modifications. The esophagus was initially rotated by 90° counterclockwise, followed by transection of two-thirds of the esophageal diameter. The unstapled esophagus was then transected with a harmonic ultrasonic scalpel to enable esophagostomy at the posterior side of the esophagus. A side-to-side esophagojejunostomy was then formed at the posterior side of the esophagus using an endoscopic linear stapler through the right lower trocar. The common entry hole was closed via hand sewing method using V-Loc suture. This procedure was termed "esophagus two-step-cut overlap method." RESULTS: Only one patient suffered from esophagojejunal anastomotic leakage but subsequently recovered after conservative treatment. Patients did not experience anastomotic bleeding or stricture. CONCLUSION: Our modified overlap method provides satisfactory surgical outcomes and overcomes several technical limitations, such as entering the false lumen of the esophagus, unnecessary pollution caused by nasogastric tube, and unintended left crus stapling during anastomosis.

18.
J Hazard Mater ; 408: 124913, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33412441

RESUMO

Global warming severely hinders both rice (Oryza sativa L.) quality and yield by increasing arsenic (As) bioavailability in paddy soils. However, details regarding As biotransformation and migration in the rice-soil system at elevated temperatures remain unclear. This study investigated the effects of increasing temperature on As behavior and translocation in rice grown in As-contaminated paddy soil at two temperature treatments (33 °C warmer temperature and 28 °C as control). The results showed that increasing temperature from 28 °C to 33 °C significantly favored total As, arsenite (As(III)) and arsenate (As(Ⅴ)) release into the soil pore-water. This increase in As bioavailability resulted in significantly higher As(III) accumulation in the whole grains at warmer treatment relative to the control. Moreover, the results suggest that increasing temperature to 33 °C promoted As(III) migration from the roots to the whole grains. Furthermore, the As(V)-reducing Xanthomonadales order and Alcaligenaceae family, and As(V) reductase-encoding arsC gene were enriched in the rhizosphere soils incubated at 33 °C. This suggests that the increase in As bioavailability in that treatment was due to enhanced As(V) reductive dissolution into the soil pore-water. Overall, this study provides new insights on how warmer future temperatures will exacerbate As accumulation in rice grains.

19.
Chem Commun (Camb) ; 57(15): 1895-1898, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33491703

RESUMO

Herein, we report a general strategy based on host-guest interactions to fabricate atomically dispersed biomimetic catalysts, which were evaluated by diboration of phenylacetylene. The structure and function of these mimics are quite similar to those of enzymes, namely, the atomically dispersed metal serves as an active site, the external macromolecular structure plays a role as an enzyme catalytic pocket to stabilize the reaction intermediates and the interactions between the intermediates and functional groups near to the active site can reduce the reaction activation energy.

20.
J Hazard Mater ; 409: 124925, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33421876

RESUMO

Iron-rich red mud is a potent radioactive drainage treatment material. However, the calcite in red mud attenuates its U adsorption capacity by restricting U adsorption onto adsorbent; it captures U as a dissociative complex in aqueous systems. This study produced macroporous iron and carbon combined calcined red mud (ICRM) and carbon calcined red mud (CRM) through calcination in the range of 500-800 °C. XRD results revealed that both series generated advantageous magnetite and calcite were fully decomposed. SEM and batch experiments highlighted ICRM calcined at 600 °C has more stable and favorable performance. The components of post-adsorption ICRM remained active, as demonstrated by FT-IR results. Additionally, ICRM@600 displayed superior U adsorption capacity (59.45 mg/g) than did all red mud adsorbents from our previous research. Zeta-potential results revealed ICRM has positive potential charges in acidic conditions, indicating it adsorbs U(VI) ions via electrostatic attraction. The main adsorption mechanisms of ICRM are surface electrostatic attraction, physical adsorption by porous structure, and chemical adsorption by active Al and Fe components. In application, ICRM@600 obtained a 82.20% U adsorption ratio in uranium mine pit drainage. Overall, this study offers theoretical guidances to radioactive drainage management and red mud reuse.

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