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1.
Diabetes Metab Syndr Obes ; 15: 2803-2811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36128059

RESUMO

Purpose: To explore the relationship between hemoglobin levels and osteoporosis and the risk factors for osteoporosis in patients with type 2 diabetes mellitus (T2DM). Patients and methods: A cross-sectional study was conducted in 495 T2DM adults. Medical data were collected from electronic medical records. Results: T2DM patients with osteoporosis had significant lower hemoglobin levels (P < 0.001). Spearman correlation analysis and logistic regression analysis showed that age, female, body mass index (BMI), smoking, drinking and hemoglobin levels were significantly associated with osteoporosis in T2DM patients (all P < 0.05). After adjustment for BMI, diabetic duration, estimated glomerular filtration rate (eGFR), smoking and drinking, a significant association between hemoglobin levels and osteoporosis was observed in T2DM males aged 50 years and older (odds ratio [OR] = 0.978, 95% confidence interval [CI]: 0.958-0.998, P = 0.030). Compared to Q3 groups with normal hemoglobin levels, Q1 groups with anemia had an odd of osteoporosis increased 2.9-fold in T2DM men after adjustment for age, BMI, diabetic duration, eGFR, smoking and drinking (P = 0.032). Conclusion: Hemoglobin levels were associated with the presence of osteoporosis in T2DM men, especially in those aged 50 years and older.

2.
ACS Appl Mater Interfaces ; 9(17): 14749-14757, 2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28406287

RESUMO

Considering the significant influence of oxygen-containing groups on the surface of carbon involved electrodes, a carbon nanotube (CNT)-based MnO2 composite catalyst was synthesized following a facile method while using polymerized ionic liquids (PIL) as sacrifice agent. Herein, the PIL (polymerized hydrophobic 1-vinyl-3-ethylimidazolium bis ((trifluoromethyl)sulfonyl)imide) wrapped CNTs were prepared. The composite was applied to support MnO2 by the treatment of KMnO4 solution, taking advantage of the reaction between PIL and KMnO4, which excludes or suppresses the oxidation of CNTs, and the as-synthesized material with fewer oxygen-containing groups acted as a cathode catalyst for Li-O2 batteries, directly avoiding the application of binders. The catalyst shows enhanced activity compared to that of the samples without PIL, as verified by the lower overpotential during discharging and charging (0.97 V at the current density of 100 mA g-1). Meanwhile, the performance parameters such as Coulombic efficiency and rate capability were also improved for the Li-O2 battery utilizing this catalyst. Further, the formation of confined Li2O2 particles could be responsible for the reduction of charge potential of Li-O2 batteries due to the synergy effect of the intrinsic catalytic activity of MnO2 and fewer oxygen functional groups on the catalyst surface.

3.
J Phys Chem B ; 117(9): 2764-72, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23398446

RESUMO

Because of its sensitivity to chemical and electrostatic characteristics, nitrile group as an infrared (IR) probe to monitor the local structure, folding kinetics, and electrostatic environment of protein, or solvation of molecular solvents, has attracted increasing attention. Herein, by choosing benzonitrile and imidazolium ionic liquids (ILs) as the IR probe and model ILs, respectively, we report that the nitrile stretching vibration (νCN) could be utilized as a simple and substantial IR probe to monitor the local environment of ILs such as hydrogen bonding (H-bonding) as well as intrinsic electric field. In 1-alkyl-3-methylimidazolium-based non-hydroxyl ILs, the νCN is in a "free" state, and is less affected by the alkyl chain, while it significantly decreases with the effective anion charge. In 1-(2-hydroxyethyl)-3-methylimidazolium-based hydroxyl ILs, however, a distinct anion-dependent νCN forming H-bonding with the hydroxyl is also observed besides the "free" νCN band. The "free" component of νCN can be further employed to determine the intrinsic electric field in both non-hydroxyl (directly) and hydroxyl (indirectly by subtracting H-bonding contribution) ILs by using vibrational Stark effect. Moreover, the result suggests that benzonitrile is preferentially located in the charge domain in ILs and it could be a more suitable probe to report the ionic network rather than the nonpolar domain in ILs.

4.
Chemistry ; 18(38): 11904-8, 2012 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-22907797

RESUMO

The electric fields of ionic liquids are only slightly higher than those of common molecular solvents, and are strongly structure-dependent; they noticeably decrease with anion size because of increased separation of ions, and slightly decrease as the alkyl chain elongates due to increasing spatial heterogeneity. These were the key results of vibrational Stark effect spectroscopy and molecular dynamics simulations.

5.
Analyst ; 136(7): 1302-4, 2011 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-21305085

RESUMO

Six ionic liquid (IL)-modified dyes were synthesized and characterized. Compared to the methyl red and methyl orange, these IL-modified [MR](-)- or [MO](-)-based dyes exhibit lower melting points and enhanced solubility, and can be used as sensitive indicators towards free proton in both aqueous and non-aqueous solutions. This work also supplies a new concept of developing novel modified materials with the ILs.

8.
J Phys Chem B ; 114(11): 3912-20, 2010 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-20199047

RESUMO

The polarity of a series of ionic liquids (ILs) based on hydroxyethyl-imidazolium moiety with various anions ([PF(6)], [NTf(2)], [ClO(4)], [DCA], [NO(3)], [AC], and [Cl]) and their corresponding nonhydroxyl ILs was investigated by solvatochromic dyes and fluorescence probe molecules. Most of the nonhydroxyl ILs exhibit anion-independent polarity with similar E(T)(30) in the narrow range of 50.7-52.6 kcal/mol, except [EMIm][AC] (49.7 kcal/mol). However, the polarity of the hydroxyl ILs covers a rather wide range (E(T)(30) = 51.2-61.7 kcal/mol) and is strongly anion-dependent. According to their E(T)(30) or E(T)(33) values, the hydroxyl ILs can be further classified into the following three groups: (Iota) acetate-based hydroxyl ILs [HOEMIm][AC] exhibit polarity scale (E(T)(30) = 51.2 kcal/mol) similar to short chain alcohol and fall in the range of the nonhydroxyl ILs; (II) Hydroxyl ILs containing anions [NO(3)], [DCA], and [Cl] exhibit comparable polarity (E(T)(30) = 55.5-56.9 kcal/mol), moderately higher than those of their nonhydroxyl ILs; (III) Hydroxyl ILs containing anions [PF(6)], [NTf(2)], and [ClO(4)] possess unusual "hyperpolarity" (E(T)(30) = 60.3-61.7 kcal/mol) close to protic ILs and water. Kamlet-Taft parameters and density functional theory calculations indicated that the greatly expanded range of polarity of hydroxyl ILs is correlated to an intramolecular synergistic solvent effect of the ionic hydrogen-bonded HBD/HBA complexes generated by intrasolvent HBD/HBA association between the anions and the hydroxyl group on cations, wherein hydroxyl group exhibits a significant differentiating effect on the strength of H-bonding and thus the polarity. Spiropyran-merocyanine equilibrium acted as a model polarity-sensitive reaction indeed shows obviously polarity-dependent solvatochromism, photochromism, and thermal reversion in hydroxyl ILs.

9.
Chemistry ; 15(3): 765-78, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19040247

RESUMO

A new series of ionic liquids composed of three cyclic sulfonium cations and four anions has been synthesized and characterized. Their physicochemical properties, including their spectroscopic characteristics, ion cluster behavior, surface properties, phase transitions, thermal stability, density, viscosity, refractive index, tribological properties, ion conductivity, and electrochemical window have been comprehensively studied. Eight of these salts are liquids at room temperature, at which some salts based on [NO(3)](-) and [NTf(2)](-) ions exhibit organic plastic crystal behaviors, and all the saccharin-based salts display relatively high refractive indices (1.442-1.594). In addition, some ionic liquids with the [NTf(2)](-) ion exhibit peculiar spectroscopic characteristics in FTIR and UV/Vis regions, whilst those salts based on the [DCA](-) ion show lower viscosities (34.2-62.6 mPa s at 20 degrees C) and much higher conductivities (7.6-17.6 mS cm(-1) at 20 degrees C) than most traditional 1,3-dialkylimidazolium salts.


Assuntos
Cátions/química , Líquidos Iônicos/química , Compostos de Sulfônio/química , Condutividade Elétrica , Eletroquímica , Líquidos Iônicos/síntese química , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Sulfônio/síntese química , Temperatura de Transição , Viscosidade
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