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In the push to achieve net-zero emissions by 2050, nuclear power will play an essential role alongside renewable wind and solar power, and correspondingly global interest and investment in this well-established technology is accelerating. The uranium present in seawater could support nuclear power generation for centuries, but traditional adsorptive separation strategies have proven ineffective for the selective extraction of uranium from this vast resource. Here, we report the synthesis of nanowires of a triazine-linked two-dimensional covalent organic framework via a solvent modulation approach, which can be used to access nanowire external diameters ranging from 50 to 200 nm. The 100 nm nanowires are exceptionally promising for the capture of uranium(VI) via photocatalytic reduction. Under simulated sunlight and without the use of sacrificial agents, the nanowires achieve a uranium uptake of 10.9 g/g from a 100 ppm uranyl(VI) solution, which is the highest reported to date among materials studied for photo and electrocatalytic uranium capture. Significantly, these nanowires exhibit a uranium adsorption capacity of 34.5 mg/g after exposure to seawater under irradiation for 42 days, a record among all materials reported to date for uranium capture.
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Inflammation and oxidative stress (OS) are the major pathogenic characteristics of acute kidney injury (AKI). Studies have shown that Schisandrin (Sch) could regulate inflammatory disease. However, the function and mechanism of Sch in AKI progression are still unknown. Here, we investigated Sch's potential effects and mechanism on mice's renal damage and macrophages induced by lipopolysaccharide (LPS). Sch decreased LPS-induced inflammatory factor production while increasing the activity of related antioxidant enzymes in macrophages and mouse kidney tissues. Hematoxylin and eosin staining revealed that Sch may have the ability to profoundly inhibit inflammatory cell invasion and tissue damage caused by LPS in renal tissue. Furthermore, Western blot and immunohistochemical studies showed that Sch exerted its effects mainly through up-regulation of nuclear factor erythroid 2-related factor 2/heme oxygenase-1 and inhibition of Toll-like receptor 4âmitogen-activated protein kinases/nuclear factor-kappa B pathways. Collectively, this study illustrates that Sch suppresses LPS-stimulated AKI by descending inflammation and OS, illuminating prospective AKI treatment options.
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OBJECTIVES: To explore the interrelationships between oral hygiene habits, oral health status and cognitive function in older adults. DESIGN: A cross-sectional study. SETTING AND PARTICIPANTS: A total of 371 participants (age 76.79 [7.99] years) were enrolled from June 2020 to November 2021 in an aged care facility. METHODS: Cognitive function was screened using the mini-mental state examination (MMSE) with adjusted cut-off points for age and education. Periodontal status (Biofilm-Gingival Interface index based on periodontal probing depth and bleeding on probing), dental status (plaque, calculus, and caries), and tooth loss were assessed through full-mouth examination. Oral hygiene habits were based on self- or informant-reporting. RESULTS: Poor periodontal status was an associated factor for MCI (OR = 2.89, 95% CI = 1.20-6.95), while multiple tooth loss (OR = 4.90, 95% CI = 1.06 ~ 22.59), brushing teeth less than once a day (OR = 2.88, 95% CI = 1.12 ~ 7.45) and delayed dental visits (OR = 2.45, 95% CI = 1.05 ~ 5.68) were associated factors for cognitive impairment. An indirect effect of brushing teeth ≥2 daily on MMSE score through periodontal status was observed only in older adults without cognitive impairment (Bootstrap-corrected B = 0.17, 95%CI = 0.03 ~ 0.36, SE = 0.08, ß = 0.08). CONCLUSIONS AND IMPLICATIONS: Adequate toothbrushing might prevent cognitive decline indirectly by improving periodontal health only in older adults without cognitive impairment. Multiple tooth loss, infrequent toothbrushing, and delayed dental visits were associated factors for cognitive impairment. Nursing professionals and health care policymakers should advocate for the improvement of basic oral hygiene in older adults, and provide regular professional oral hygiene care for older adults with cognitive impairment. PATIENT OR PUBLIC CONTRIBUTION: The information on oral health habits of this study was based on an interview with the participants or their caregivers during the study period.
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Salud Bucal , Pérdida de Diente , Humanos , Anciano , Higiene Bucal , Estudios Transversales , CogniciónRESUMEN
Radiation-induced intestinal injury (RIII) is a common complication after radiation therapy in patients with pelvic, abdominal, or retroperitoneal tumours. Recently, in the model of DSS (Dextran Sulfate Sodium Salt) -induced intestinal inflammatory injury, it has been found in the study that transgenic mice expressing hVDR in IEC (Intestinal Epithelial Cell) manifest highly anti-injury properties in colitis, suggesting that activated VDR in the epithelial cells of intestine may inhibit colitis by protecting the mucosal epithelial barrier. In this study, we investigated the effect of the expression and regulation of VDR on the protection of RIII, and the radiosensitivity in vitro experiments, and explored the initial mechanism of VDR in regulating radiosensitivity of IEC. As a result, we found that the expression of VDR in intestinal tissues and cells in mice can be induced by ionizing radiation. VDR agonists are able to prolong the average survival time of mice after radiation and reduce the radiation-induced intestinal injury. For lack of vitamin D, the radiosensitivity of intestinal epithelial cells in mice increased, which can be reduced by VDR activation. Ensuing VDR activation, the radiation-induced intestinal stem cells damage is decreased, and the regeneration and differentiation of intestinal stem cells is promoted as well. Finally, on the basis of sequencing analysis, we validated and found that VDR may target the HIF/PDK1 pathway to mitigate RIII. We concluded that agonism or upregulation of VDR expression attenuates radiation-induced intestinal damage in mice and promotes the repair of epithelial damage in intestinal stem cells.
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Colitis , Receptores de Calcitriol , Animales , Ratones , Colitis/patología , Sulfato de Dextran/efectos adversos , Células Epiteliales/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patología , Ratones Endogámicos C57BL , Ratones Transgénicos , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Traumatismos Experimentales por RadiaciónRESUMEN
As an emerging surgical technology, tissue removal systems have been widely used in the treatment of endometrial polyps due to its characteristics of less endometrial damage, shorter learning curve and clearer vision of the operative field. There are few cases in the literature reporting serious complications after endometrial polypectomy using tissue removal systems. As known, septic shock is a rare complication following hysteroscopic polypectomy. Now, we present the case of a 23-year-old woman who developed septic shock after polypectomy with tissue removal system. The patient had a history of recurrent vaginitis for more than half a year. Due to endometrial polyps, she was admitted to our hospital and scheduled to undergo hysteroscopic endometrial polypectomy. Three hours after the endometrial polypectomy using the tissue removal system, the patient had shock symptoms such as increased body temperature, decreased blood pressure and increased heart rate. Then, the patient was successfully treated and discharged after anti-infection and anti-shock treatments. The purpose of this case report is to remind clinicians to consider the possibility of serious infection and comprehensively evaluate the risk of infection before choosing hysteroscopic devices for endometrial polyps, especially for patients who choose the mechanical hysteroscopic tissue removal systems. Furthermore, the mechanical hysteroscopic tissue removal systems should be used with caution in patients with previous recurrent vaginitis.
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Pólipos , Choque Séptico , Enfermedades Uterinas , Neoplasias Uterinas , Vaginitis , Femenino , Humanos , Adulto Joven , Endometrio/patología , Pólipos/cirugía , Choque Séptico/complicaciones , Choque Séptico/patología , Enfermedades Uterinas/cirugía , Neoplasias Uterinas/patologíaRESUMEN
OBJECTIVE: The objective of the study was to evaluate the effectiveness of telehealth-based exercise intervention on pain, physical function and quality of life in patients with knee osteoarthritis. DESIGN: A systematic review and meta-analysis of randomised controlled trials (RCTs). METHODS: Six databases (PubMed, Embase, Cochrane Library, CINAHL, PEDro and Web of Science Core Collection) were searched for relevant randomised controlled trials published from database inception to 3 June 2021. Reviewers independently screened the literature, extracted data and used the Cochrane Collaboration Risk of Bias Tool for quality assessment. A meta-analysis and subgroup analyses, stratified by control condition, intervention duration and delivery type, were conducted by Revman 5.4. The study was reported in compliance with PRISMA statement. RESULTS: A total of 9 independent RCTs with 861 participants were included. The meta-analysis showed that the telehealth-based exercise interventions significantly reduced pain in KOA patients (SMD = -0.28, 95% CI [-0.49, -0.08], p < .01) and produced similar effects to controls in terms of physical function and quality of life. Subgroup analysis revealed that telehealth-based exercise interventions were superior to the use of exercise booklet and usual care in terms of pain and physical function and were similar to face-to-face exercise treatment; a long-term (>3 months) intervention and the use of web and smartphone APPs to deliver exercise interventions were associated with better pain relief and physical function. CONCLUSIONS: Telehealth-based exercise intervention is an effective strategy for KOA management during the COVID-19 epidemic, and it is significantly better than usual care in reducing knee pain and improving physical function and was able to achieve the effects of traditional face-to-face exercise treatment. Although the duration and type of delivery associated with the effect of the intervention have been identified, patient preference and acceptability need to be considered in practice.
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COVID-19 , Osteoartritis de la Rodilla , Telemedicina , Humanos , Osteoartritis de la Rodilla/terapia , Calidad de Vida , Terapia por Ejercicio , DolorRESUMEN
BACKGROUND: Conventional wisdom affirmed that diabetes was irreversible, but current research shows that lifestyle interventions may achieve diabetes remission among patients with type 2 diabetes mellitus. Recently, many original studies have examined the effectiveness of lifestyle interventions. However, great heterogeneity in intervention approaches resulted in inconsistent intervention effects. AIMS: The aim of this study was to determine the effectiveness of lifestyle interventions for diabetes remission among patients with type 2 diabetes mellitus. METHODS: PubMed, CINAHL, Embase, Web of Science Core Collection, and Cochrane Library were searched for relevant articles from their inceptions to March 26, 2021. Reference lists and a relevant journal were searched manually as well. Both randomized controlled trials and quasi-experimental studies were included. The quantitative data extracted from the selected studies included diabetes remission rate, weight, and quality of life score. The risk of bias was assessed by the Cochrane and Joanna Briggs Institute's tool. RevMan version 5.3. was used to carry out the meta-analysis. RESULTS: This systematic review included 12 studies involving 3997 patients with type 2 diabetes mellitus. Lifestyle interventions included in the studies were mainly divided into diet-only interventions and diet combined with physical activity interventions. Among them, there were three types of diet: (1) low-energy diet, (2) low carbohydrate diet, and (3) Mediterranean diet. Moderate-intensity aerobic and resistance physical activity, walking, and maintaining habitual physical activity were the three types of physical activity interventions employed in the included studies. The results indicated that lifestyle interventions were effective for achieving diabetes remission, reducing weight, and improving quality of life in patients with type 2 diabetes mellitus. LINKING EVIDENCE TO ACTION: Lifestyle interventions were associated with significant effects on diabetes remission, reducing weight, and improving quality of life. As an important part of lifestyle interventions, diet and physical activity have a significant effect on blood glucose and weight control in patients with type 2 diabetes mellitus. It is therefore suggested that the contents of lifestyle interventions should focus on diet and physical activity.
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Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/terapia , Calidad de Vida , Estilo de Vida , Ejercicio Físico , GlucemiaRESUMEN
Lithium (Li) extraction from brines is a major barrier to the sustainable development of batteries and alloys; however, current separation technology suffers from a trade-off between ion selectivity and permeability. Herein, a crown ether mechanically interlocked 3D porous organic framework (Crown-POF) was prepared as the porous filler of thin-film nanocomposite membranes. Crown-POF with penta-coordinated (four Ocrown atoms and one Ntert-amine atom) adsorption sites enables a special recognition for Li+ ion. Moreover, the four Ntert-amine atoms on each POF branch facilitate the flipping motion of Li+ ion along the skeletal thread, while retaining the specified binding pattern. Accordingly, the crown ether interlocked POF network displays an ultrafast ion transfer rate, over 10â times that of the conventional porous materials. Notably, the nanocomposite membrane gives high speed and selectivity for Li+ ion transport as compared with other porous solid-based mixed-matrix membranes.
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Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by inflammation infiltration of the synovial tissues and the fibroblast-like synoviocytes. Tectoridin is a botanical active ingredient with anti-inflammatory properties. In this study, the anti-arthritic effects of tectoridin and its mechanism of action are examined in TNF-α-induced human fibroblast-like synovial cells (HFLSs cells) and complete Freund's adjuvant (CFA)-stimulated arthritic mice. Arthritis progression was evaluated via bodyweight, hind paw swelling, organ index, and synovial pathology. IL-1ß, IL-6 and other pro-inflammatory factors concentrations, and the expression of MAPK pathway proteins in HFLSs cells and arthritic mice were measured using ELISA and western blotting. Results showed that tectoridin significantly decreased the swelling of the paws and joints as well as the increased immune organ index within CFA-induced arthritic mice. Histopathological analysis showed that tectoridin alleviated the lesions of ankle joints and synovial tissues induced by CFA. Secretion of pro-inflammatory cytokines in TNF-α-induced HFLSs cells and CFA-stimulated arthritic mice were also abated by tectoridin. Similarly, the presence of tectoridin significantly inhibited the abnormal phosphorylation levels of ERK, JNK, and p38 in vivo and in vitro. All those results highlighted that tectoridin exhibits anti-arthritis effects by inhibiting MAPK-mediated inflammatory responses.
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Artritis Experimental , Artritis Reumatoide , Animales , Artritis Experimental/inducido químicamente , Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Citocinas/metabolismo , Edema/inducido químicamente , Edema/tratamiento farmacológico , Edema/patología , Adyuvante de Freund/efectos adversos , Humanos , Isoflavonas , Ratones , Factor de Necrosis Tumoral alfa/efectos adversosRESUMEN
WHAT IS KNOWN AND OBJECTIVE: Aflibercept, a recombinant protein designed to suppress the vascular endothelial growth factor (VEGF) signalling pathway, has been used in patients with metastatic colorectal cancer (mCRC). We conducted the first meta-analysis to systematically review the efficacy and safety of aflibercept in mCRC. METHODS: PubMed Central/Medline, Embase and cochrane library were systematically searched for randomized controlled trials and single-arm clinical trials on aflibercept plus chemotherapy for the treatment of mCRC through 9 September 2021. RESULTS: Ten studies comprising 2049 patients met the inclusion criteria. The pooled estimate rates were 16.0% for 12mPFS, 64.4% for 12mOS, 32.5% for ORR, 83.5% for DCR, while the rates of III/IV AEs rate were 80.2% respectively. The pooled estimate rates were 16.8% for III/IV diarrhoea, 22.3% for III/IV hypertension, 29.5% for III/IV neutropenia, 7.3% for III/IV proteinuria and 8.6% for III/IV oral mucositis. CONCLUSIONS: Analysis of data from randomized controlled trials(RCT) and single-arm clinical trials confirmed the good efficacy of aflibercept plus chemotherapy in mCRC, while the safety of the treatment is concerning.
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Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Fluorouracilo/uso terapéutico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Proteínas Recombinantes de Fusión/efectos adversos , Neoplasias del Recto/tratamiento farmacológico , Factor A de Crecimiento Endotelial VascularRESUMEN
OBJECTIVE: To investigate the effects of morroniside on inflammatory and oxidative stress in lipopolysaccharide (LPS)-induced inflammatory bowel disease (IBD) cell model. METHODS: NCM460 cells were treated with 2-, 5-, or 10-µg/mL LPS for 24 h to develop an IBD cell model. MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) colorimetric assay was performed to uncover the role of morroniside on the viability of LPS-treated NCM460 cells. Flow cytometry and immunoblot assays were performed to confirm the effects of morroniside on the apoptosis of LPS-treated NCM460 cells. Quantitative polymerase chain reaction and enzyme-linked-immunosorbent serologic assays were performed to confirm the effects of morroniside on inflammatory and oxidative stress by measuring the levels of tumor necrosis factor-α, interleukin-1ß, IL-6, superoxide dismutase, malondialdehyde, total antioxidant capacity, and myeloperoxidase. In addition, immunoblot and immunofluorescence assays were performed to detect the effects of morroniside on NLRP3 and NF-κB pathways. RESULTS: Monosine attenuated LPS-induced injury of NCM460 cells. Monosine reduced LPS-induced inflammation in NCM460 cells. In addition, morroniside reduced LPS-induced oxidative stress in NCM460 cells. Mechanically, morroniside suppressed NLRP3 and NF-κB pathways, and alleviated LPS-induced inflammatory and oxidative stress in IBD. CONCLUSION: Morroniside could serve as a promising drug for treating IBD.
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Enfermedades Inflamatorias del Intestino , Lipopolisacáridos , Humanos , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Estrés Oxidativo , Transducción de Señal , Inflamación/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológicoRESUMEN
BACKGROUND: Tectoridin, widely extracted and separated from the rhizome of Iris tectorum Maxim, is extensively reported to have affluent bioactivity, but rarely reported to have anti-inflammatory effects. In this study, we aim to investigate the anti-inflammatory effects and the underlying mechanisms of tectoridin. METHODS: Here, RAW264.7 macrophages were stimulated with Lipopolysaccharide (LPS) for the inflammation model in vitro. Experimental animals received tectoridin and Dexamethasone (DEX) before LPS injection for endotoxic shock mouse model in vivo. The pro-inflammatory mediators and cytokines in the cell supernatant and serum were detected by ELISA kits. The tissue damages were assessed by biochemical indexes and H&E staining. Immunohistochemistry and Western blot were performed for the detection of proteins. RESULTS: Our data showed that tectoridin attenuated the LPS-up-regulated nitric oxide (NO), interleukin-6 (IL-6), and interleukin-18 (IL-18) from macrophages and tumor necrosis factor-α (TNF-α); (IL-6) and (IL-1ß) in the serum levels. Besides, our histopathological study showed that the damages caused by LPS in the lung, liver, and kidney tissues were decreased. Furthermore, our results demonstrated that tectoridin inhibited the activation of TLR4-NF-κB/NLRP3 signaling proved by immunohistochemistry assay and Western blot. CONCLUSION: Taken all together, tectoridin might have the potential ability of anti-inflammatory effects and the possible mechanism may be relevant to its inhibition of TLR4-NF-κB/NLRP3 signaling.
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Lipopolisacáridos , FN-kappa B , Animales , Antiinflamatorios/farmacología , Citocinas/metabolismo , Dexametasona/farmacología , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Interleucina-18 , Interleucina-6 , Isoflavonas , Lipopolisacáridos/toxicidad , Ratones , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Óxido Nítrico/metabolismo , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfaRESUMEN
Metal-organic frameworks (MOFs) have broad application prospects in the development of efficient, sensitive and single select gas sensors. However, in order to construct a chemical resistance gas sensor based on MOFs, the problem of poor conductivity of MOFs must be solved. In this work, we synthesized CoCe-BTC, which based on the organic ligands of trimesic acid (H3BTC) by the water bath method and prepared CoCe-BTC/PEDOT composite film on an interdigital electrode by the spin coating process. Compared with pure MOF material, the conductivity of CoCe-BTC/PEDOT is significantly improved. Under a dry room temperature environment and N2 as the carrier gas, the response of the sensor to NO2 is about 1.2 times that of pure PEDOT and has a shorter response time. It has great repeatability and selectivity and shows a dynamic response with the change of NO2 gas concentration (5-50 ppm).
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OBJECTIVE: We aimed to evaluate door-to-puncture time (DPT) and door-to-recanalization time (DRT) without directing healthcare by neuro-interventionalist support in the emergency department (ED) by workflow optimization and improving patients' outcomes. METHODS: Records of 98 consecutive ischemic stroke patients who had undergone endovascular therapy (EVT) between 2018 to 2021 were retrospectively reviewed in a single-center study. Patients were divided into three groups: pre-intervention (2018-2019), interim-intervention (2020), and post-intervention (January 1st 2021 to August 16th, 2021). We compared door-to-puncture time, door-to-recanalization time (DRT), puncture-to-recanalization time (PRT), last known normal time to-puncture time (LKNPT), and patient outcomes (measured by 3 months modified Rankin Scale) between three groups using descriptive statistics. RESULTS: Our findings indicate that process optimization measures could shorten DPT, DRT, PRT, and LKNPT. Median LKNPT was shortened by 70 min from 325 to 255 min(P < 0.05), and DPT was shortened by 119 min from 237 to 118 min. DRT shortened by 132 min from 338 to 206 min, and PRT shortened by 33 min from 92 to 59 min from the pre-intervention to post-intervention groups (all P < 0.05). Only 21.4% of patients had a favorable outcome in the pre-intervention group as compared to 55.6% in the interventional group (P= 0.026). CONCLUSION: This study demonstrated that multidisciplinary cooperation was associated with shortened DPT, DRT, PRT, and LKNPT despite challenges posed to the healthcare system such as the COVID-19 pandemic. These practice paradigms may be transported to other stroke centers and healthcare providers to improve endovascular time metrics and patient outcomes.
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COVID-19 , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/cirugía , Pandemias , Punciones , Estudios Retrospectivos , Accidente Cerebrovascular/terapia , Trombectomía , Tiempo de Tratamiento , Resultado del Tratamiento , Flujo de TrabajoRESUMEN
Porous aromatic framework materials with high stability, sensitivity, and selectivity have great potential to provide new sensors for optoelectronic/fluorescent probe devices. In this work, a luminescent porous aromatic framework material (LNU-23) was synthesized via the palladium-catalyzed Suzuki cross-coupling reaction of tetrabromopyrene and 1,2-bisphenyldiborate pinacol ester. The resulting PAF solid exhibited strong fluorescence emission with a quantum yield of 18.31%, showing excellent light and heat stability. Because the lowest unoccupied molecular orbital (LUMO) of LNU-23 was higher than that of the nitro compounds, there was an energy transfer from the excited LNU-23 to the analyte, leading to the selective fluorescence quenching with a limit of detection (LOD) ≈ 1.47 × 10-5 M. After integrating the luminescent PAF powder on the paper by a simple dipping method, the indicator papers revealed a fast fluorescence response to gaseous nitrobenzene within 10 s, which shows great potential in outdoor fluorescence detection of nitro compounds.
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Nitrocompuestos , Paladio , Ésteres , Colorantes Fluorescentes , Nitrobencenos , Porosidad , PolvosRESUMEN
The strong radioactivity of iodine compounds derived from nuclear power plant wastes has motivated the development of highly efficient adsorbents. Porous aromatic frameworks (PAFs) have attracted much attention due to their low density and diverse structure. In this work, an azo group containing PAF solid, denoted as LNU-58, was prepared through Suzuki polymerization of tris-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-phenyl)-amine and 3,5-dibromoazobenzene building monomers. Based on the specific polarity properities of the azo groups, the electron-rich aromatic fragments in the hierarchical architecture efficiently capture iodine molecules with an adsorption capacity of 3533.11 mg g-1 (353 wt%) for gaseous iodine and 903.6 mg g-1 (90 wt%) for dissolved iodine. The iodine uptake per specific surface area up to 8.55 wt% m-2 g-1 achieves the highest level among all porous adsorbents. This work illustrates the successful preparation of a new type of porous adsorbent that is expected to be applied in the field of practical iodine adsorption.
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Yodo , Adsorción , Aminas/química , Yoduros , PorosidadRESUMEN
Due to the frequent oil/organic solvent leakage, efficient oil/water separation has attracted extensive concern. However, conventional porous materials possess nonpolar building units, which reveal relatively weak affinity for polar organic molecules. Here, two different polarities of superhydrophobic porous aromatic frameworks (PAFs) were synthesized with respective orthoposition and paraposition C=O groups in the PAF linkers. The conjugated structure formed by a large number of alkynyl and benzene ring structures enabled porous and superhydrophobic quality of PAFs. After the successful preparation of the PAF solids, PAF powders were coated on polyester fabrics by a simple dip-coating method, which endowed the resulting polyester fabrics with superhydrophobicity, porosity, and excellent stability. Based on the unique structure, the oil/water separation efficiency of two superhydrophobic flexible fabrics was more than 90% for various organic solvents. Polar LNU-26 PAF showed better separation performance for the polar oils. This work takes the lead in adopting the polar groups as building units for the preparation of porous networks, which has great guiding significance for the construction of advanced oil/water separation materials.
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High-speed capturing of uranyl (UO22+) ions from seawater elicits unprecedented interest for the sustainable development of the nuclear energy industry. However, the ultralow concentration (â¼3.3 µg L-1) of uranium element leads to the slow ion diffusion inside the adsorbent particle, especially after the transfer paths are occupied by the coexisted interfering ions. Considering the geometric dimension of UO22+ ion (a maximum length of 6.04-6.84 Å), the interlayer spacing of graphene sheets was covalently pillared with phenyl-based units into twice the ionic length (13 Å) to obtain uranyl-specific nanofluidic channels. Applying a negative potential (-1.3 V), such a charge-governed region facilitates a unipolar ionic transport, where cations are greatly accelerated and co-ions are repelled. Notably, the resulting adsorbent gives the highest adsorption velocity among all reported materials. The adsorption capacity measured after 56 days of exposure in natural seawater is evaluated to be â¼16 mg g-1. This novel concept with rapid adsorption, high capacity, and facile operating process shows great promise to implement in real-world uranium extraction.
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An iodine-mediated stereoselective synthesis of seven-membered oxa-bridged rings via in situ generated cycloheptenols was reported. This process was realized through the combination of C-C σ-bond cleavage and C-O bond-forming reactions in a one-pot fashion from simple and easily accessible raw materials. The formation of carbon radicals initiated by I2 was the key to the reaction.
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Highly atom-economical tandem reactions have been developed for the synthesis of pyrano[3,2-b]indoles or cyclopenta[b]indoles tethered with 7-, 8-, or 9-membered rings. These reactions first undergo a carbon-carbon σ-bond cleavage reaction of cyclic ß-ketoesters. Next, in the presence of CuCl2 and Ag2CO3, intramolecular O-H/C-H coupling occurs to give pyrano[3,2-b]indoles. This is the first example for capture of the enoloxyl radical of the intramolecular C-O bond formation reaction, whereas C3 nucleophilic addition afforded cyclopenta[b]indoles using TsOH·H2O.