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1.
Chem Sci ; 15(28): 10858-10866, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39027287

ABSTRACT

Reducing carbon dioxide (CO2) to high value-added chemicals using renewable electricity is a promising approach to reducing CO2 levels in the air and mitigating the greenhouse effect, which depends on high-efficiency electrocatalysts. Copper-based catalysts can be used for electroreduction of CO2 to produce C2+ products with high added value, but suffer from poor stability and low selectivity. Herein, we propose a strategy to enhance the field effect by varying the cubic corner density on the surface of Cu2O microspheres for improving the electrocatalytic performance of CO2 reduction to C2+ products. Finite element method (FEM) simulation results show that the high density of cubic corners helps to enhance the local electric field, which increases the K+ concentration on the catalyst surface. The results of CO2 electroreduction tests show that the FEC2+ of the Cu2O catalyst with high-density cubic corners is 71% at a partial current density of 497 mA cm-2. Density functional theory (DFT) calculations reveal that Cu2O (111) and Cu2O (110) can effectively reduce the energy barrier of C-C coupling and improve the FEC2+ at high K+ concentrations relative to Cu2O (100). This study provides a new perspective for the design and development of efficient CO2RR catalysts.

2.
Int Immunopharmacol ; 127: 111348, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38086268

ABSTRACT

Chronic postsurgical pain (CPSP) is increasingly recognized as a public health issue. Recent studies indicated the innate immune pathway of cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)-stimulator of interferon genes (STING) was involved in pain regulation. However, the detailed mechanisms remain unclear. Previous studies found A1 reactive astrocytes in the spinal cord contributed to CPSP. This study aimed to investigate the roles and mechanisms of the cGAS-STING pathway in regulating the generation of A1 reactive astrocytes during CPSP. First, CPSP model was established using skin/muscle incision and retraction (SMIR) in rats. We found that cGAS-STING pathway was activated accompanied with an increase in mitochondrial DNA in the cytosol in the spinal cord following SMIR. Second, a STING inhibitor C-176 was intrathecally administrated. We found that C-176 decreased the expression of type I interferons and A1 reactive astrocytes in the spinal cord, and alleviated mechanical allodynia in SMIR rats. Third, cyclosporin A as a mitochondrial permeability transition pore blocker was intrathecally administrated. We found that cyclosporin A decreased the leakage of mitochondrial DNA and inhibited the activation of cGAS-STING pathway. Compared with C-176, cyclosporin A exhibits similar analgesic effects. The expression of type I interferons and A1 reactive astrocytes in the spinal cord were also down-regulated after intervention with cyclosporin A. Moreover, simultaneous administration of cyclosporin A and C-176 did not show synergistic effects in SMIR rats. Therefore, our study demonstrated that the cGAS-STING pathway activated by the leakage of mitochondrial DNA contributed to chronic postsurgical pain by inducing type I interferons and A1 reactive astrocytes in the spinal cord.


Subject(s)
Interferon Type I , Rats , Animals , Interferon Type I/metabolism , DNA, Mitochondrial/metabolism , Astrocytes/metabolism , Cyclosporine , Spinal Cord/metabolism , Nucleotidyltransferases/genetics , Nucleotidyltransferases/metabolism , Pain, Postoperative
3.
Small ; 19(41): e2303172, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37312395

ABSTRACT

Formic acid is receiving intensive attention as being one of the most progressive chemical fuels for the electrochemical reduction of carbon dioxide. However, the majority of catalysts suffer from low current density and Faraday efficiency. To this end, an efficient catalyst of In/Bi-750 with InOx nanodots load is prepared on a two-dimensional nanoflake Bi2 O2 CO3 substrate, which increases the adsorption of * CO2 due to the synergistic interaction between the bimetals and the exposure of sufficient active sites. In the H-type electrolytic cell, the formate Faraday efficiency (FE) reaches 97.17% at -1.0 V (vs reversible hydrogen electrode (RHE)) with no significant decay over 48 h. A formate Faraday efficiency of 90.83% is also obtained in the flow cell at a higher current density of 200 mA cm-2 . Both in-situ Fourier transform infrared spectroscopy (FT-IR) and theoretical calculations show that the BiIn bimetallic site can deliver superior binding energy to the * OCHO intermediate, thereby fundamentally accelerating the conversion of CO2 to HCOOH. Furthermore, assembled Zn-CO2 cell exhibits a maximum power of 6.97 mW cm-1 and a stability of 60 h.

4.
J Colloid Interface Sci ; 649: 703-712, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37385035

ABSTRACT

Spinel ZnMn2O4 with a three-dimensional channel structure is one of the important cathode materials for aqueous zinc ions batteries (AZIBs). However, like other manganese-based materials, spinel ZnMn2O4 also has problems such as poor conductivity, slow reaction kinetics and structural instability under long cycles. Herein, ZnMn2O4 mesoporous hollow microspheres with metal ion doping were prepared by a simple spray pyrolysis method and applied to the cathode of aqueous zinc ion battery. Cation doping not only introduces defects, changes the electronic structure of the material, improves its conductivity, structural stability, and reaction kinetics, but also weakens the dissolution of Mn2+. The optimized 0.1 % Fe-doped ZnMn2O4 (0.1% Fe-ZnMn2O4) has a capacity of 186.8 mAh g-1 after 250 charge-discharge cycles at 0.5 A g-1 and the discharge specific capacity reaches 121.5 mAh g-1 after 1200 long cycles at 1.0 A g-1. The theoretical calculation results show that doping causes the change of electronic state structure, accelerates the electron transfer rate, and improves the electrochemical performance and stability of the material.

5.
J Pain Res ; 16: 1533-1546, 2023.
Article in English | MEDLINE | ID: mdl-37193359

ABSTRACT

Background and Purpose: Peripheral nerve block is often used to relieve postoperative pain. But the effect of nerve block on inflammatory response is not fully understood. Spinal cord is the primary center of pain processing. This study is to investigate the effect of single sciatic nerve block on the inflammatory response of the spinal cord in rats with plantar incision and the combined effect with flurbiprofen. Methods: The plantar incision was used to establish a postoperative pain model. Single sciatic nerve block, intravenous flurbiprofen or the combination of both were used for intervention. The sensory and motor functions after nerve block and incision were evaluated. The changes of IL-1ß, IL-6, TNF-α, microglia and astrocytes in the spinal cord were examined by qPCR and immunofluorescence respectively. Results: Sciatic nerve block with 0.5% ropivacaine in rats induced sensory block for 2h and motor block for 1.5h. In the rats with plantar incision, the single sciatic nerve block did not alleviate postoperative pain or inhibit the activation of spinal microglia and astrocytes, but the levels of IL-1ß and IL-6 in spinal cord were decreased when the nerve block wore off. The combined effect of a single sciatic nerve block and intravenous flurbiprofen not only decreased the levels of IL-1ß, IL-6, and TNF-α, but also relieved the pain and alleviated the activation of microglia and astrocytes. Conclusion: The single sciatic nerve block cannot improve postoperative pain or inhibit the activation of spinal cord glial cells, but can reduce the expression of spinal inflammatory factors. Nerve block combined with flurbiprofen can inhibit spinal cord inflammation and improve postoperative pain. This study provides a reference for rational clinical application of nerve block.

6.
Inorg Chem ; 62(17): 6856-6863, 2023 May 01.
Article in English | MEDLINE | ID: mdl-37078576

ABSTRACT

The hydrogen evolution reaction (HER) involves two-step elementary reactions, providing an opportunity to establish dual-site synergistic catalysts. This work demonstrates carbon-supported Pt single atoms and clusters (Pt1+Cs-NPC) as an efficient catalyst for acidic HER, which exhibits an ultralow Tafel slope of 12.5 mV/dec and an overpotential of 24 mV at 10 mA/cm2 with an ultralow platinum content of 3.8 wt %. The Pt mass activity and turnover frequency (TOF) are 10.2 times and 5.4 times that of commercial Pt/C, respectively. The density functional theory (DFT) study shows that the Pt cluster regulates the electronic state structure of the adjacent Pt single atom, so that the ΔGH* at the Pt1 site approaches 0. Moreover, the DFT study confirms that Pt clusters and neighboring Pt single atoms can synergistically catalyze the Tafel step and reduce the energy barrier in forming the H-H bond. At the same time, the platinum cluster reduces the energy barrier of the nearby platinum single-atom site to the Heyrovsky step and accelerates the reaction with hydrated hydrogen ions. Studies have shown that platinum clusters and platinum single-atom composite loading structures exhibit excellent activity for the Volmer-Tafel or Volmer-Heyrovsky reaction paths of HER reactions. This work provides a clear understanding of the synergistic effect of Pt1+Cs-NPC, which provides guidance for developing efficient HER catalysts.

7.
Inorg Chem ; 61(30): 12003-12011, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35838600

ABSTRACT

Bismuth-based catalysts exhibit excellent activity and selectivity for the electroreduction of carbon dioxide (CO2). However, single-component bismuth-based catalysts are not satisfactory for the electrochemical reduction of CO2 to formic acid, mainly due to their high hydrogen production, low electrical conductivity, and small catalytic current density. Herein, we used a coordination strategy to recombine Bi and In at the molecular level to form Bi/In bimetallic metal-organic frameworks (MOFs), which were then calcined to obtain MOF-derived Bi/In bimetallic oxide nanoparticles embedded in carbon networks. Thanks to the synergistic effect of bimetallic components, high specific surface area, suitable pore size distribution, and high electrical conductivity of the carbon network, the material exhibits excellent activity and selectivity for electroreduction of CO2 to formate. In H-type electrolyzers, the formate Faradaic efficiency reaches 91% at -0.9 V (vs RHE) and does not decrease significantly within 48 h. In situ Fourier transform infrared spectroscopy confirms the reaction intermediates and reveals that CO2 electroreduction is dominant by the *OCHO pathway.

8.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 10): m341-2, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25484671

ABSTRACT

Two 4,4'-[1,3-phenyl-enebis(-oxy)]dibenzoate anions bridge two 1,10-phenanthroline-chelated Zn(II) cations about a center of inversion to generate the dinuclear title compound, [Zn2(C20H12O6)2(C12H8N2)2]·2H2O. The geometry about the Zn(II) atom is a distorted octa-hedron. In the crystal, the mol-ecules are connected by classical O-H⋯O hydrogen bonds, weak C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming a three dimensional network. π-π stacking is also observed between aromatic rings of adjacent mol-ecules, centroid-centroid distances are 3.753 (2), 3.5429 (16) and 3.5695 (17) Å.

9.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): m361-2, 2014 Nov 01.
Article in English | MEDLINE | ID: mdl-25484775

ABSTRACT

In the title salt, [Zn(C6H15NO3)2](C8H4O4), the Zn(II) cation, located on a centre of inversion, is coordinated by four O atoms and two N atoms from two tridentate 2-[bis-(2-hy-droxy-eth-yl)amino]-ethanol (BHEA) ligands, giving rise to a slightly distorted octa-hedral geometry. The terephthalate dianion, located about a centre of inversion, is not coordinated to Zn(II) but is connected through O-H⋯O contacts with [Zn(BHEA)2](2+) cations, leading to a three-dimensional crystal structure.

10.
Exp Ther Med ; 7(5): 1337-1341, 2014 May.
Article in English | MEDLINE | ID: mdl-24940435

ABSTRACT

The aim of the present study was to investigate the ultrastructure and content of collagen in uterosacral ligaments and paraurethral tissues in patients with pelvic organ prolapse (POP) and stress urinary incontinence (SUI), analyzing the association between POP and collagen dysfunction. The study comprised three groups: Control, POP and POP with SUI (n=30 per group). Histological characteristics of collagen fiber were observed and the diameters were measured using light and electron microscopy to determine the Type I and Type III collagen content of the main ligament in the urethral specimens. In the POP and POP with SUI groups, observations included diffuse atrophy of smooth muscles, active fibroblast metabolism, swollen mitochondria and visible Golgi apparatus. The collagen fibril diameters in the cardinal ligaments, uterosacral ligaments and paraurethral tissues were significantly greater in the POP and POP with SUI groups compared with those in the control group (P<0.01). In addition, the expression levels of Type I and Type III collagen were significantly lower in the POP and POP with SUI groups when compared with the control group (P<0.01). In the POP with SUI group, pelvic tissues were frail, resulting in smooth muscle bundles comminuting and arranging in a disorganized pattern. Fibroblast and myoblast metabolisms were active and new microvascular cells were weak. However, the collagen fibril diameter increased. Thus, collagen and ultrastructural changes in the pelvic floor may be associated with the development of POP and SUI.

11.
Article in English | MEDLINE | ID: mdl-24046563

ABSTRACT

The asymmetric unit of the title compound, [Mn3(C12H6O12)(H2O)6] n , comprises one Mn(II) ion, one third of a cyclo-hexane-1,2,3,4,5,6-hexa-carboxyl-ate anion and two aqua ligands. The anion is completed by application of a -3 axis. The Mn(II) ion is six-coordinated by six O atoms from two aqua ligands and three different cyclo-hexa-carboxyl-ate anions in an octa-hedral geometry. The six carboxyl-ate groups adopt a bridging bidentate mode to ligate the Mn(II) ions. Thus, each cyclo-hexane-1,2,3,4,5,6-hexa-carboxyl-ate anion adopts a µ9-connected mode, ligating nine different Mn(II) ions and forming a three-dimensional framework. In the framework, there are strong O-H⋯O hydrogen-bonding inter-actions, which further stabilize the crystal structure.

12.
Article in English | MEDLINE | ID: mdl-22259546

ABSTRACT

In the title compound, C(24)H(17)N(2)O(4) (+)·NO(3) (-)·0.25H(2)O, the central pyridine ring of the 2',6'-bis-(4-carb-oxy-phen-yl)-4,4'-bipyridin-1-ium cation is almost coplanar with one benzene ring [dihedral angle = 1.03 (5)°], while it makes dihedral angles of 9.59 (5)° with the other benzene ring and 13.66 (6)° with the pyridinium ring. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds link the cations and nitrate anions into a sheet in the (302) plane. The crystal structure also exhibits π-π inter-actions between the central pyridine ring and the benzene rings of neighboring mol-ecules [centroid-centroid distance = 3.6756 (13) Å].

13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 4): m397, 2011 Apr 01.
Article in English | MEDLINE | ID: mdl-21753933

ABSTRACT

In the title compound, {[Zn(C(8)H(5)N(2)O(2)S)(2)]·3H(2)O}(n), the Zn(II) atom, lying on a twofold rotation axis, is four-coordinated by two S atoms and two O atoms from four 2-sulfido-1H-benzimidazol-3-ium-5-carboxyl-ate (H(2)mbidc) ligands in a distorted tetra-hedral geometry. Two H(2)mbidc ligands bridge two Zn(II) atoms, generating a double-chain along [[Formula: see text]01]. Adjacent chains are linked by N-H⋯O and O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular network. One of the two water molecules also lies on a twofold rotation axis.

14.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): m1576, 2010 Nov 17.
Article in English | MEDLINE | ID: mdl-21589262

ABSTRACT

In the title coordination polymer, [Cu(3)(C(5)H(7)N(2)O(7)P(2))(2)(H(2)O)(2)](n), one Cu(II) atom is five-coordinated by five O atoms from three 1-hy-droxy-2-(imidazol-3-ium-1-yl)ethane-1,1-diyldiphospho-nate (L) ligands in a distorted square-pyramidal geometry. The other Cu(II) atom, lying on an inversion center, is six-coordinated in a distorted octa-hedral geometry by four O atoms from two L ligands and two O atoms from two water mol-ecules. The five-coordinated Cu(II) atoms are linked by phospho-nate O atoms of the L ligands, forming a polymeric chain. These chains are further linked by the six-coordinated Cu atoms into a layer parallel to (01). N-H⋯O and O-H⋯O hydrogen bonds connect the layers into a three-dimensional supra-molecular structure.

15.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3147, 2010 Nov 13.
Article in English | MEDLINE | ID: mdl-21589446

ABSTRACT

In the title compound, C(12)H(11)NO(2), the phenolic ring is inclined at an angle of 32.70 (1)° with respect to the pyridine ring. In the crystal, inter-molecular O-H⋯N hydrogen bonds link the mol-ecules into C(11) chains along [001].

16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): m47, 2010 Dec 08.
Article in English | MEDLINE | ID: mdl-21522567

ABSTRACT

In the title compound, {[Ag(C(6)H(4)NO(2))(C(6)H(12)N(4))(H(2)O)]·2H(2)O}(n), the Ag(I) atom shows a distorted triangular pyramidal geometry,, formed by two N atoms from two hexa-methyl-ene-tetra-amine (hmt) ligands and one N atom from a pyridine-4-carboxyl-ate (4-pdc) ligand and one water mol-ecule. The hmt ligands bridge the Ag atoms, forming a chain along [001]. The carboxyl-ate group of the 4-pdc ligand is uncoordinated. O-H⋯O hydrogen bonds between the water mol-ecules and carboxyl-ate groups stabilize the structure.

17.
Acta Crystallogr C ; 65(Pt 9): m340-2, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19726847

ABSTRACT

In the title coordination compound, [Zn(C(12)H(6)O(4))(C(14)H(14)N(4))](n), the two Zn(II) centers exhibit different coordination environments. One Zn(II) center is four-coordinated in a distorted tetrahedral environment surrounded by two carboxylate O atoms from two different naphthalene-1,4-dicarboxylate (1,4-ndc) anions and two N atoms from two distinct 1,4-bis(imidazol-1-ylmethyl)benzene (1,4-bix) ligands. The coordination of the second Zn(II) center comprises two N atoms from two different 1,4-bix ligands and three carboxylate O atoms from two different 1,4-ndc ligands in a highly distorted square-pyramidal environment. The 1,4-bix ligand and the 1,4-ndc anion link adjacent Zn(II) centers into a two-dimensional four-connected (4,4) network. The two (4,4) networks are interpenetrated in a parallel mode.


Subject(s)
Organometallic Compounds/chemistry , Zinc/chemistry , Crystallography, X-Ray , Ligands , Models, Molecular
18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m876, 2009 Jul 04.
Article in English | MEDLINE | ID: mdl-21583341

ABSTRACT

In the title compound, [Cd(C(16)H(10)O(4))(C(14)H(8)N(4))(H(2)O)]·0.5C(3)H(7)NO, the Cd(II) atom is six-coordinated by two N atoms from one pyrazino[2,3-f][1,10]phenanthroline ligand, three carboxyl-ate O atoms from two different 4,4'-ethyl-enedibenzoate ligands, and one water mol-ecule in a distorted octa-hedral environment. The two 4,4'-ethyl-enedibenzoate dianions are located on inversion centres bridging two neighboring Cd(II) centres. O-H⋯O hydrogen-bonding inter-actions further stabilize the crystal structure. The DMF molecule is equally disordered about a center of inversion.

19.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m944, 2009 Jul 18.
Article in English | MEDLINE | ID: mdl-21583394

ABSTRACT

In the title compound, {[Zn(C(12)H(8)O(4))(C(12)H(8)N(2))(H(2)O)]·0.5H(2)O}(n), each Zn(II) atom is six-coordinated by two N atoms from one 1,10-phenanthroline (phen), three carboxyl-ate O atoms from two different L ligands [H(2)L = 3,3'-(p-phenyl-ene)diacrylic acid] and one water mol-ecule in a distorted octa-hedral environment. The two L dianions are situated across inversion centres and bridge neighbouring Zn(II) centres, yielding a chain propagating parallel to [100]. O-H⋯O hydrogen bonds between the coordinated water molecule, the solvent water molecule (half-occupied) and the carboxylate O atoms further stabilize the structure.

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