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1.
Opt Express ; 27(19): 27385-27395, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674600

RESUMO

In a single magneto-optical (MO) waveguide, the dispersion of guided bulk wave is reciprocal in the Voigt configuration. Here we show that the parity-time (P T) phase in two coupled MO waveguides can be nonreciprocal if the waveguides are properly biased. The nonreciprocal P T phase is closely related to the asymmetric field profile induced by the MO effect that modifies the coupling strength between adjacent waveguides. We show that it is feasible to switch between broken and conserved P T phases by simply reversing the magnetic bias or the propagating direction of wave. Theoretical analysis and numerical calculation prove our theory. This investigation highlights a flexible method in manipulating the field dynamics of waveguide arrays by using the novel properties of P T phase especially the exceptional points.

2.
Curr Med Chem ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701843

RESUMO

Diabetic nephropathy (DN) is one of the most common and important microvascular complications of diabetes mellitus (DM). The main clinical features of DN are proteinuria and a progressive decline in renal function , which are associated with structural and functional changes in the kidney. The pathogenesis of DN is multifactorial, including genetic, metabolic and haemodynamic factors, which can trigger a sequence of events. Controlling metabolic risks such as hyperglycaemia, hypertension and dyslipidaemia is not enough to slow the progression of DN. Recent studies have emphasized immunoinflammation as a critical pathogenic factor in the progression of DN. Therefore, targeting inflammation is considered a potential and novel treatment strategy for DN. In this review, we will briefly introduce the inflammatory process of DN and discuss the anti-inflammatory effects of antidiabetic drugs when treating DN.

3.
Carbohydr Polym ; 226: 115295, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31582086

RESUMO

Tumor-associated macrophages (TAMs) with an M2-like phenotype have been linked to the proliferation, invasion and metastasis of tumor cells. Resetting tumor-associated macrophages represents an attractive target for an effective cancer immunotherapy. WCCP-N-b, a novel linear 3-O-methylated galactan, isolated from Cantharellus cibarius, can convert tumor-promoting M2-like macrophages to tumor-inhibiting M1-like phenotype. On a cellular mechanistic level, WCCP-N-b inhibited M2-like macrophages polarization through suppression of STAT6 activation. Furthermore, WCCP-N-b increased the phosphorylation of mitogen-activated protein kinases (MAPKs) and degradation of IκB-α through targeting Toll-like receptor 2 (TLR2). The activation of MAPKs and degradation of IκB-α were responsible for converting M2-like macrophages to M1-like macrophages. Importantly, cell culture supernatants of WCCP-N-b-treated M2-like macrophages could inhibit the cell viability of B16F1 and B16F10. Our findings provide a potential natural and harmless polysaccharide for macrophage-based tumor immunotherapy.

4.
Small ; : e1903880, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588682

RESUMO

Endophthalmitis, derived from the infections of pathogens, is a common complication during the use of ophthalmology-related biomaterials and after ophthalmic surgery. Herein, aiming at efficient photodynamic therapy (PDT) of bacterial infections and biofilm eradication of endophthalmitis, a pH-responsive zeolitic imidazolate framework-8-polyacrylic acid (ZIF-8-PAA) material is constructed for bacterial infection-targeted delivery of ammonium methylbenzene blue (MB), a broad-spectrum photosensitizer antibacterial agent. Polyacrylic acid (PAA) is incorporated into the system to achieve higher pH responsiveness and better drug loading capacity. MB-loaded ZIF-8-PAA nanoparticles are modified with AgNO3 /dopamine for in situ reduction of AgNO3 to silver nanoparticles (AgNPs), followed by a secondary modification with vancomycin/NH2 -polyethylene glycol (Van/NH2 -PEG), leading to the formation of a composite nanomaterial, ZIF-8-PAA-MB@AgNPs@Van-PEG. Dynamic light scattering, transmission electron microscopy, and UV-vis spectral analysis are used to explore the nanoparticles synthesis, drug loading and release, and related material properties. In terms of biological performance, in vitro antibacterial studies against three kinds of bacteria, i.e., Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus, suggest an obvious superiority of PDT/AgNPs to any single strategy. Both in vitro retinal pigment epithelium cellular biocompatibility experiments and in vivo mice endophthalmitis models verify the biocompatibility and antibacterial function of the composite nanomaterials.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31606200

RESUMO

OBJECTIVE: To investigate the effects of thyroid-stimulating hormone (TSH) on the expression of endothelial nitric oxide synthase (eNOS) in human microvascular endothelial cells (HMEC-1) and explore the potential mechanism. MATERIALS AND METHODS: Expression of thyroid-stimulating hormone receptor (TSHR) in HMEC-1 cells was determined by immunofluorescence, reverse transcription-polymerase chain reaction (RT-PCR), and Western blotting. Cell proliferation and the production of nitric oxide (NO) and superoxide anion (SA) were measured after TSH treatment. eNOS expression and AKT phosphorylation were detected by Western blotting. RESULTS: TSHR was expressed in HMEC-1 cells. TSH promoted HMEC-1 cell proliferation and SA production, but inhibited NO generation by dose-dependent blocking of mRNA and protein expression of eNOS. Mechanism studies demonstrated that TSH promoted AKT phosphorylation (P<0.05), and that LY294002 inhibited the reduction of eNOS expression by TSH. Moreover, TSH activated the AKT signaling pathway through binding to TSHR on HMEC-1 cells. CONCLUSIONS: TSH inhibits NO production via the TSHR/AKT signaling pathway.

6.
Lancet ; 394(10205): 1226, 2019 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-31591979
7.
J Diabetes ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31602779

RESUMO

BACKGROUND: We aim to design a scoring model for differential diagnosis between diabetic nephropathy (DN) and non-diabetic renal disease (NDRD) in type 2 diabetic patients through a combination of clinical variables. METHODS: 170 patients with type 2 diabetes who underwent kidney biopsies were included and divided into three groups according to pathological findings: DN group (n=46), MIX group (DN+NDRD, n=54), NDRD group (n=70). Clinical characteristics and laboratory data were collected and compared among groups. Variables with significant statistical difference between DN and NDRD patients were analyzed by logistic regression to predict the presence of NDRD, then a scoring model was established based on regression coefficient and further validated in an independent cohort of 67 patients prospectively. RESULTS: On biopsy, 72.9% of patients had NDRD and the most common pathological type was membranous nephropathy. The established scoring model for predicting NDRD included five predictors: age, systolic blood pressure, hemoglobin, duration of diabetes, absence of diabetic retinopathy. The model demonstrated good discrimination and calibration (area under curve [AUC] 0.863, 95%CI 0.800-0.925; H-L P=0.062). Furthermore, high prediction accuracy (AUC=0.900; 95% CI, 0.815-0.985) in the validation cohort proved the stability of the model. CONCLUSIONS: We present a simple, robust scoring model for predicting the presence of NDRD with high accuracy (0.85) for the first time. This decision support tool provides a noninvasive method for differential diagnosis of DN and NDRD, which may help clinicians assess the risk-benefit ratio of kidney biopsy for type 2 diabetic patients with renal impairment.

8.
Macromol Rapid Commun ; : e1900435, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31596528

RESUMO

Sequence-controlled polymerization is the forefront of polymer chemistry. Herein, the feasibility of sequence regulation by using organocatalyzed ring-opening polymerization (ROP) is demonstrated. In particular, ring expansion strategy is employed to synthesize pre-organized monomers 1 and 2. ROP is conducted by using 1,5,7-triazabicyclo[4.4.0]dec-5-ene and benzyl alcohol as the catalyst and initiator, respectively. Poly(ester amide)s (PEAs) P1-P3 comprising glycolic acid, lactic acid, and 7-aminoheptanoic acid units are obtained in high molecular weights and good yields. NMR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry results verify the microstructural integrity of P1 and P2. Differential scanning calorimetry results show that PEA without methyl branches is crystalline. Moreover, thermal stability, surface wettability, and degradation profiles of P1-P3 are also investigated.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31608243

RESUMO

Mycoplasma pneumoniae (M. pneumoniae) is responsible for pneumonia, and is a causative agent of other respiratory tract infections (e.g., bronchiolitis and tracheobronchitis). Herein, we established and applied a multiple cross displacement amplification (MCDA) coupled with a nanoparticle-based lateral flow biosensor (LFB) assay (MCDA-LFB) for rapid, simple, and reliable detection of target pathogen. A set of 10 primers was designed based on M. pneumoniae-specific P1 gene, and optimal reaction conditions were found to be 30 min at 65°C. The detection results were visually reported using a biosensor within 2 min. The M. pneumoniae-MCDA-LFB method specifically detected only M. pneumoniae templates, and no cross-reactivity was generated from non-M. pneumoniae isolates. The analytical sensitivity for this assay was 50 fg of genomic templates in the pure cultures, as obtained from colorimetric indicator and real-time turbidimeter analysis. The assay was applied to 197 oropharyngeal swab samples collected from children highly suspected of M. pneumoniae infection, and compared to culture-based method and real-time PCR assay. The detection rates of M. pneumoniae using a culture-based method, real-time PCR assay, and MCDA-LFB assay were 8.1%, 33.0%, and 52.3%, respectively, which indicated that the MCDA-LFB assay was superior to the culture-based method and real-time PCR method for detection of target agent. Using this protocol, 25 min for rapid template extraction followed by MCDA reaction (30 min) combined with LFB detection (2 min) resulted in a total assay time of ~60 min. In conclusion, the MCDA-LFB assay established in this report was a simple, rapid, sensitive, and reliable assay to detect M. pneumoniae strains, and can be used as a potential diagnostic tool for M. pneumoniae in basic and clinical laboratories.

10.
J Hematol Oncol ; 12(1): 103, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623653

RESUMO

BACKGROUND: Circular RNAs (circRNAs) represent a type of endogenous noncoding RNAs that are generated by back-splicing events and favor repetitive sequences. Recent studies have reported that cancer-associated chromosomal translocations could juxtapose distant complementary repetitive intronic sequences, resulting in the aberrant formation of circRNAs. However, among the reported fusion genes, only a small number of circRNAs were found to originate from fusion regions during gene translocation. We question if circRNAs could also originate from fusion partners during gene translocation. METHODS: Firstly, we designed divergent primers for qRT-PCR to identify a circRNA circAF4 in AF4 gene and investigated the expression pattern in different types of leukemia samples. Secondly, we designed two small interfering RNAs specially targeting the back-spliced junction point of circAF4 for functional studies. CCK8 cell proliferation and cell cycle assay were performed, and a NOD-SCID mouse model was used to investigate the contribution of circAF4 in leukemogenesis. Finally, luciferase reporter assay, AGO2 RNA immunoprecipitation (RIP), and RNA Fluorescent in Situ Hybridization (FISH) were performed to confirm the relationship of miR-128-3p, circAF4, and MLL-AF4 expression. RESULTS: We discovered a circRNA, named circAF4, originating from the AF4 gene, a partner of the MLL fusion gene in MLL-AF4 leukemia. We showed that circAF4 plays an oncogenic role in MLL-AF4 leukemia and promotes leukemogenesis in vitro and in vivo. More importantly, knockdown of circAF4 increases the leukemic cell apoptosis rate in MLL-AF4 leukemia cells, while no effect was observed in leukemia cells that do not carry the MLL-AF4 translocation. Mechanically, circAF4 can act as a miR-128-3p sponge, thereby releasing its inhibition on MLL-AF4 expression. We finally analyzed most of the MLL fusion genes loci and found that a number of circRNAs could originate from these partners, suggesting the potential roles of fusion gene partner-originating circRNAs (named as FP-circRNAs) in leukemia with chromosomal translocations. CONCLUSION: Our findings demonstrate that the abnormal elevated expression of circAF4 regulates the cell growth via the circAF4/miR-128-3p/MLL-AF4 axis, which could contribute to leukemogenesis, suggesting that circAF4 may be a novel therapeutic target of MLL-AF4 leukemia.

11.
Environ Sci Technol ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31607119

RESUMO

Particulate matter with aerodynamic diameters ≤1 µm (PM1) has a greater impact on the human health but has been less studied due to fewer ground observations. This study attempts to improve the retrieval accuracy and spatial resolution of satellite-based PM1 estimates using the new ground-based monitoring network in China. Therefore, a space-time extremely randomized trees (STET) model is first developed to estimate PM1 concentrations at a 1 km spatial resolution from 2014 to 2018 across mainland China. The STET model can derive daily PM1 concentrations with an average across-validation coefficient of determination of 0.77, a low root-mean-square error of 14.6 µg/m3, and a mean absolute error of 8.9 µg/m3. PM1 concentrations are generally low in most areas of China, except for the North China Plain and Sichuan Basin where intense human activities and poor natural conditions are prevalent, especially in winter. Moreover, PM1 pollution has greatly decreased over the past 5 years, benefiting from emission control in China. The STET model, incorporating the spatiotemporal information, shows superior performance in PM1 estimates relative to previous studies. This high-resolution and high-quality PM1 data set in China (i.e., ChinaHighPM1) can be greatly useful for air pollution studies in medium- or small-scale areas.

12.
Pediatrics ; 144(5)2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31653675

RESUMO

OBJECTIVES: Xpert Mycobacterium tuberculosis and rifampicin (MTB/RIF) Ultra assay has increasingly been used in adult tuberculosis diagnosis, but data relating to its diagnostic accuracy in children are lacking. Because a qualified sputum specimen is difficult to obtain in children, this study evaluated the diagnostic value of Ultra in childhood tuberculosis using bronchoalveolar lavage fluid. METHODS: The accuracy of Ultra was calculated by using bacteriologic results and clinical evidence as reference standards. Concordance between Ultra and Xpert MTB/RIF assays was assessed by using к coefficients. RESULTS: In total, 93 children with pulmonary tuberculosis and 128 children with respiratory tract infections were enrolled. The sensitivity of Ultra, in all pulmonary tuberculosis cases and in bacteriologically confirmed tuberculosis cases, was 70% and 91%, respectively. Ultra could detect Mycobacterium tuberculosis in 58% of cases with negative culture or acid-fast-staining results. The specificity of Ultra was 98%. There was no significant difference in sensitivity between samples with a volume ≤1 and >1 mL (66% vs 73%; P = .50; odds ratio [OR] = 0.71). Among 164 children for which Ultra and Xpert were simultaneously performed, the sensitivity was 80% and 67%, respectively, indicating good agreement (к = 0.84). An additional 6 children were identified as Ultra-positive but Xpert-negative. The positive rate decreased from 93% to 63% after 1 month (P = .01; OR = 0.12) and to 71% after 2 months (P = .03; OR = 0.18) of antituberculosis treatment. CONCLUSIONS: Ultra using bronchoalveolar lavage fluid has good sensitivity compared with bacteriologic tests and adds clinical value by assisting the rapid and accurate diagnosis of pulmonary tuberculosis in children.

13.
Sci Rep ; 9(1): 13315, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527664

RESUMO

A major challenge in regenerative medicine is the repair of injured neurons. Regeneration of laser-cut C. elegans neurons requires early action of core apoptosis activator CED-4/Apaf1 and CED-3/caspase. While testing models for CED-4 as a candidate calcium-sensitive activator of repair, we unexpectedly discovered that amino acid substitutions affecting alpha-helix-6 within the CED-4 caspase recruitment domain (CARD) confer a CED-4 gain-of-function (gf) activity that increases axonal regrowth without disrupting CED-4 apoptosis activity. The in vivo caspase reporter CA-GFP reveals a rapid localized increase in caspase activity upon axotomy, which is absent in ced-4 and ced-3 loss-of-function mutants but present in the ced-4(gf) mutant. The ced-3 loss-of-function mutation can significantly suppress the axonal regrowth of the ced-4(gf) mutant, indicating that CED-4(gf) regeneration depends on CED-3 caspase. Thus, we identified a subdomain within the CED-4 CARD that regulates the dynamic and controlled caspase activity required for efficient regeneration.

14.
J Biomol Struct Dyn ; : 1-12, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31549586

RESUMO

New Delhi metallo-ß-lactamase (NDM-1) is the most recent addition to the class of metallo-ß-lactamases (MBLs). This enzyme leads to antibiotic resistance in clinical treatments owing to its exertion of hydrolysis activity in almost all clinically available ß-lactam antibiotics. Consequently, inhibitors targeting NDM-1 have attracted considerable research attention. However, progress has been slow regarding the study of the quantitative structure-activity relationship (QSAR) of NDM-1 inhibitors. In this study, a three-dimensional QSAR (3 D-QSAR) for NDM-1 inhibitors was established using Topomer CoMFA. The multiple correlation coefficients of the fitting model, leave-one-out cross validation, and external validation were found to be 0.761, 0.976, and 0.972, respectively. Topomer Search was used to design 16 new molecules that inhibit NDM-1 using R-group search from ZINC databases, 10 of which had comparatively high activities against NDM-1. The results indicate that Topomer CoMFA and Topomer Search can be used to design new NDM-1 inhibitors and guide the design of new NDM-1 drugs with good predictive capability. Furthermore, from molecular modeling and binding free-energy calculation, it was found that the newly designed molecules can bind to the catalytic region of NDM-1. Additionally, the newly designed inhibitors formed strong interactions with Ile35, Met67, Phe70, Trp93, His122, His189, Cys208, and His250 around the Zn2+-centered active region of NDM-1. These findings will facilitate the development of more effective NDM-1 inhibitors for use as potential antibacterial agents. Communicated by Ramaswamy H. Sarma.

15.
Sci Total Environ ; 692: 879-891, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539993

RESUMO

The next-generation geostationary meteorological Himawari-8 satellite carrying the Advanced Himawari Imager (AHI) allows frequent observations of the atmosphere, the surface, and oceans every 10 min. With its retrieval algorithms recently updated, Himawari-8/AHI Version 2 Level 2 aerosol products are now available. However, these retrievals have not yet undergone a quality assessment. This study aims to comprehensively validate the official aerosol optical properties derived from Himawari-8/AHI over land and ocean. Aerosol Robotic Network and Sun-Sky Radiometer Observation Network ground-based measurements at 98 stations in the Himawari-domain region are used to validate aerosol optical depth (AOD, or τ) retrievals at 500 nm and Ångström exponent (AE) retrievals at 440-675 nm from the year 2016. The AOD retrievals agree well with surface observations (i.e., from linear regression, slope = 0.876, intercept = 0.076, and correlation coefficient = 0.756) with a mean absolute error and a root-mean-square error of 0.168 and 0.293, respectively. On site and regional scales, large uncertainties are seen, especially in Australia (significant overestimation) and South Asia (significant underestimation). The AOD retrievals can correctly capture daily variations and show the best (worst) performance in summer (spring). The AE performance is poorer on all scales, showing overall underestimations, especially in Australia, Southeast Asia, and China. The data quality of AOD retrievals improves as the vegetation coverage and the AE increases. This suggests that the official aerosol retrieval algorithm still faces great challenges over bright surfaces and under coarse-particle-dominated conditions. In general, approximately 61% and 64% of the AOD matchups meet the newly defined expected errors of [0.330 × τ + 0.024; -0.132 × τ - 0.125] and [0.519 × τ + 0.005; -0.007 × τ - 0.194] determined by ground measurements and aerosol retrievals, respectively. The highly variable accuracy of aerosol retrievals raises a concern about the reliability of the current product under different environmental conditions and underlying surfaces. It also sheds light on what future improvements need implementing to the aerosol retrieval algorithm.

16.
Adv Mater ; : e1902044, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483546

RESUMO

High-performance uncooled photodetectors operating in the long-wavelength infrared and terahertz regimes are highly demanded in the military and civilian fields. Photothermoelectric (PTE) detectors, which combine photothermal and thermoelectric conversion processes, can realize ultra-broadband photodetection without the requirement of a cooling unit and external bias. In the last few decades, the responsivity and speed of PTE-based photodetectors have made impressive progress with the discovery of novel thermoelectric materials and the development of nanophotonics. In particular, by introducing hot-carrier transport into low-dimensional material-based PTE detectors, the response time has been successfully pushed down to the picosecond level. Furthermore, with the assistance of surface plasmon, antenna, and phonon absorption, the responsivity of PTE detectors can be significantly enhanced. Beyond the photodetection, PTE effect can also be utilized to probe exotic physical phenomena in spintronics and valleytronics. Herein, recent advances in PTE detectors are summarized, and some potential strategies to further improve the performance are proposed.

17.
ACS Appl Mater Interfaces ; 11(41): 38061-38067, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31535551

RESUMO

MXenes, an emerging class of two-dimensional (2D) transition-metal carbide materials, have received increasing attention for their interesting physiochemical properties. For not only MXenes but also other 2D materials, delamination is a requisite step for the exploitation of their unique properties. In this work, a facile method for exfoliating Ti3C2Tx MXene to nanosheets of small size with the aid of poly(vinylpyrrolidone) (PVP) is designed, which has never been reported to our knowledge. Since both hydrophobic methylene groups and hydrophilic amide groups are provided with PVP, this method is applicable in a wide range of solvents, such as ethanol, water, and chloroform. Considering the charge detrapping and trapping behavior of 2D transition-metal materials in PVP dielectric, a memory device with the configuration of reduced graphene oxide (rGO)/Ti3C2Tx-PVP/Au is directly fabricated with these well-dispersed Ti3C2Tx-PVP composites by the solution process technique. Interestingly, the resultant device exhibits a typical bistable electrical switching, ultralow switching voltage (∼0.9 V), and a nonvolatile rewritable memory effect with the function of flash. This work might pave the way of using MXenes for future data storage, which is an indispensable field nowadays.

18.
Eur J Med Chem ; 183: 111694, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31561044

RESUMO

Isocitrate dehydrogenase 1 (IDH1), which catalyzes the conversion of isocitrate to α-ketoglutarate, is one of key enzymes in the tricarboxylic acid cycle (TCA). Hotspot mutation at Arg132 in IDH1 that alters the function of IDH1 by further converting the α-ketoglutarate(α-KG) to 2-hydroxyglutarate (2-HG) have been identified in a variety of cancers. Because the IDH1 mutations occur in a significant portion of gliomas and glioblastomas, it is important that IDH1 inhibitors have to be brain penetrant to treat IDH1-mutant brain tumors. Here we report the efforts to design and synthesize a novel serial of mutant IDH1 inhibitors with improved activity and the blood-brain barrier (BBB) penetration. We show that compound 5 exhibits good brain exposure and potent 2-HG inhibition in a HT1080-derived mouse xenograft model, which makes it a potential preclinical candidate to treat IDH1-mutant brain tumors.

19.
J Colloid Interface Sci ; 555: 315-322, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31394318

RESUMO

Catalysis benefits from biomimetic materials with sophisticated structures because a variety of functions can be integrated into one structure, satisfying the demands of a diverse range of applications. Magnetic catalysts have been widely used in various applications, but the magnetic components are most commonly used for recycling. In this study, we report the fabrication of magnetic nanocatalysts composed of a support of magnetic nanobars and Ag nanoparticles confined between two silica layers. Notably, the catalysts are constructed as nanoscale stirring bars that are able to generate disturbances at this scale. More importantly, the catalysts can be applied in both macro- and micro-systems, effectively addressing the conventional mixing method. The catalysts can then be conveniently separated from the system after use. The performances of magnetic nanoscale catalysts are well maintained through recycling.

20.
Inorg Chem ; 58(16): 11085-11090, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31385697

RESUMO

Because of their nontoxicity, economic applicability, and excellent performance on adsorptive desulfurization, the fabrication of Cu(I) sites onto porous supports has drawn much attention. However, high temperatures (usually ≥700 °C) are required for the formation of Cu(I) sites from Cu(II) species through the traditional autoreduction method, which is unworkable for thermolabile metal-organic frameworks (MOFs). Here, we report a strategy named vapor-induced reduction (VIR) to convert Cu(II) species to Cu(I) in MIL-101(Cr), in which ethanol is used as an environmentally benign reductant. The entire formation of Cu(I) from Cu(II) with more than 96% selectivity is allowed, at a relatively low temperature of 200 °C, and well-maintains the structure of the MOF. Moreover, the generated Cu(I) sites exhibit good performances in adsorption desulfurization with regard to both activity and reusability.

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