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1.
RSC Adv ; 12(25): 15740, 2022 May 23.
Article in English | MEDLINE | ID: mdl-35685701

ABSTRACT

[This corrects the article DOI: 10.1039/D2RA01300B.].

3.
J Org Chem ; 84(22): 14679-14687, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31631666

ABSTRACT

In addition to the 1,9- and 1,7-C60 adducts, the 1,23-C60 adducts are an important type of C60 derivatives, where the property of the fullerene compounds is significantly affected by the addition pattern. However, much less is known on the adducts due to the less availability of the compounds. Herein, the hydroxide-promoted reactions of C60 with 2-alkylmalonates are reported, which produce the 1,23-C60 adducts with improved efficiency. The reactions were studied with the in situ vis-NIR spectral measurement in order to probe into the reaction mechanism. The obtained 1,23-C60 adducts exhibited good thermal stability and better solubility with respect to the 1,7-isomers.

4.
Nanomaterials (Basel) ; 9(8)2019 Aug 02.
Article in English | MEDLINE | ID: mdl-31382424

ABSTRACT

A hierarchical composite based on the modified reduced graphene oxide with platinum-nickel decorated polyaniline nano-spheres (rGO/PANI@PtNi) was facilely prepared via microwave-assisted self-reduction for an application in nonenzymatic hydrogen peroxide (H2O2) detection. Compared to the pristine rGO, the composite exhibited a much tougher surface due to the stacking of conductive PANI nano-spheres on rGO sheets, leading to good dispersion of PtNi nanoparticles and a large active area. Furthermore, the multi-valance Ni2+/3+ in the PtNi particles effectively promoted the catalytic property of Pt sites and facilitated a superior electrochemical performance of PtNi alloy than that of neat Pt. Owing to the synergistic effect of the improved electrical conductivity and the promoted electrocatalytical property, the modified glassy carbon electrode (GCE) with rGO/PANI@PtNi nanocomposite displayed an outstanding electrochemical sensitivity towards H2O2 with a fast response time (<2 s), a wide linear range (0.1-126.4 mM), a low detection limit (0.5 µM), as well as a long-life stability for one week without obvious degradation. This novel strategy opens a novel and promising approach to design high performance sensors for H2O2 detection.

5.
Polymers (Basel) ; 11(4)2019 Apr 12.
Article in English | MEDLINE | ID: mdl-31013826

ABSTRACT

We fabricated one fibrous-membrane type of flexible and lightweight supported catalyst via loading platinum-nickel nanoparticles (PtNi NPs) directly on the polydopamine-coated polymethylmethacrylate electrospun-fibers (PMMA@PDA). The polymer support with the PDA layer provided numerous active sites, leading to well-monodispersed and sized PtNi NPs on the nanofibers. Through the rational design of PtNi NPs, the resultant catalyst system exhibited 90% conversion for decomposing HCHO (10 ppm) at room temperature with only a low dosage (0.02 g), retaining the high activity for 100 hours. This superior catalytic performance stems from the formate oxidation, which was the key intermediate during HCHO decomposition, and was promoted by the existence of a sufficient Pt-OH-Ni interface in the PtNi NPs with an appropriate Pt/Ni ratio of 1:5. Such tailored Pt-based nanoparticles ideally work together with the polymer nanofibers as a support for catalytic reaction. Compared with classical catalysts, our system can handle a comparable efficiency with much lower air resistance and remarkably lower dosage. Furthermore, the membrane-like morphology provides easy handling and minimizes the leaching of catalyst nanoparticles.

6.
J Org Chem ; 83(22): 13716-13725, 2018 Nov 16.
Article in English | MEDLINE | ID: mdl-30352153

ABSTRACT

Three C70 tetraadducts, 2,10-(MeO)2-5,9-Bn2C70 (6), 1,56-Bn2-2,57-(MeO)2C70 (7, 2 o'clock isomer), and 1,41-Bn2-2,58-(MeO)2C70 (8, 12 o'clock isomer), were obtained from the reaction of C70 with MeO- and BnBr (benzyl bromide). The structures of 6-8 were resolved via single-crystal X-ray diffraction and spectroscopic characterizations. Computational calculations on the electrophilic Fukui functions fk+, the stability of reaction intermediates, and activation barriers for the key processes of the reaction were performed to rationalize the regioselectivity of the reaction. A conversion of the 5 and 12 o'clock intermediates to the 2 o'clock intermediate was proposed to account for the regioselectivity related to the 2-fold additions at the two distinctive polar regions of C70. Electrochemical study showed a similar electron deficiency for the 2 and 12 o'clock isomers, while the 2,5,9,10-tetraadduct was more electron deficient with respect to the 2 and 12 o'clock isomers.

7.
J Org Chem ; 81(15): 6838-42, 2016 08 05.
Article in English | MEDLINE | ID: mdl-27387300

ABSTRACT

Methoxylation of the singly bonded 1,4-1',4'-BnC60-C60Bn dimer afforded 1,4-OMe(Bn)C60, a 1,4-C60 adduct with sterically less demanding addends, as the major adduct. The situation was different from that of direct functionalization of C60, where 1,2-OMe(Bn)C60 was obtained as the major product. The reaction was studied with in situ vis-NIR spectroscopy and computational calculations to obtain a better understanding of this unusual regioselectivity. The stability difference between 1,2- and 1,4-OMe(Bn)C60 was studied.

8.
Nephron ; 132(3): 207-14, 2016.
Article in English | MEDLINE | ID: mdl-26890857

ABSTRACT

BACKGROUND/AIM: It has been shown that hypertension (HT) and prehypertension (Pre-HT) are associated with increased cardiovascular risk. However, the significance of secondary HT/Pre-HT in children with IgA nephropathy (IgAN) is uncertain. This study aimed to examine the clinical and histopathological features of pediatric patients with HT/Pre-HT. METHODS: Data on children with IgAN from a single Chinese nephrology center were retrospectively reviewed. Morphological changes were evaluated using the Oxford classification, parameters including crescents, glomerular activity index, glomerular chronicity index (GCI), arterial lesions and Lee's grading. The clinical and pathological features were compared according to the occurrence of HT/Pre-HT. RESULTS: One hundred and eight previously untreated children with IgAN were included. HT/Pre-HT was present in 19.44% of children. Children with HT/Pre-HT were older (14.67 ± 2.37 vs. 12.07 ± 2.94 years, p < 0.01) and had higher uric acid (380.62 vs. 301.68 µmol/l, p < 0.01) and lower estimated glomerular filtration rate (eGFR; 89.95 vs. 111.84 ml/min/1.73 m2, p < 0.01). These children also had a higher proportion of segmental glomerulosclerosis or adhesion, GCI, tubular atrophy/interstitial fibrosis and arteriole wall thickening (all p < 0.05). Blood pressure (BP) values were significantly correlated with eGFR, uric acid, segmental glomerulosclerosis or adhesion, tubular atrophy/interstitial fibrosis and arteriole wall thickening (all p < 0.05). In particular, serum uric acid levels had a stronger association with systolic BP (r = 0.434, p < 0.01). CONCLUSION: Our results show that elevated serum uric acid level might be a marker of HT/Pre-HT. In renal histology, chronic lesions were more severe and prevalent in patients with HT/Pre-HT than in those without HT/Pre-HT.


Subject(s)
Glomerulonephritis, IGA/pathology , Hypertension, Renal/pathology , Kidney/pathology , Prehypertension/pathology , Adolescent , Age Factors , Blood Pressure , Child , Child, Preschool , Female , Glomerular Filtration Rate , Glomerulonephritis, IGA/complications , Glomerulosclerosis, Focal Segmental/complications , Glomerulosclerosis, Focal Segmental/pathology , Humans , Hypertension, Renal/etiology , Kidney Glomerulus/pathology , Male , Prehypertension/etiology , Retrospective Studies , Uric Acid/blood
9.
J Org Chem ; 80(3): 1557-63, 2015 Feb 06.
Article in English | MEDLINE | ID: mdl-25546630

ABSTRACT

The stability of the anionic species of the ortho and para regioisomers of (MeO)BnC(2n) (Me = methyl, Bn = benzyl, n = 30 or 35) has been examined. The results show that the ortho adducts (electronically favored regioisomers) are stable upon receiving one or two electrons, while the para ones (sterically favored adducts) decompose by removing the methoxy group under similar conditions. Computational calculations indicate that the stability of the anionic species is significantly affected by the electronic structure, where the [5,6]-double bond is responsible for the instability of the reduced species of the para adducts. Further study with 1,15-(MeO)2-2,4-Bn2C60, an adduct with both the ortho and para positioned methoxy, shows that the reduced species is stable, indicating that the 1,2,4,15-configuration is an electronically preferential structure even though it has a [5,6]-double bond.

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