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1.
J Nanosci Nanotechnol ; 20(2): 769-778, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383072

RESUMO

A super absorbent was synthesized from calcium-aluminum waste residue of aluminum industrial using a facile hydrothermal method. The XRD results revealed that the main phase of hydrothermal product at 120 °C is CaSO4 ·2H2O, with a small amount of Al(OH)3. The as-prepared products were used to investigate the adsorptive applications in Congo red (CR) removal, and the results showed that the products treated at 120 °C had the best adsorption properties. The maximum adsorption capacity reaches about 1860.11 mg/g with a removal rate of 99.75%. Furthermore, the used adsorbent could be regenerated for at least four cycles through a calcination procedure, indicating its potential as an excellent adsorbent for the removal of CR dye from wastewater. The adsorption behavior was analyzed by Langmuir, Freundlich and Sips isotherms, and the adsorption proved to be a multilayer adsorption. This facile method presented here may provide promise synthesis of high-effective and low-cost adsorbents from industrial solid waste and achieve the goal of "using waste to treat waste" in the future.

2.
J Chem Inf Model ; 59(5): 2009-2025, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30920827

RESUMO

In the present work, we develop a coarse-grained (CG) model for polyimide (PI) at 800 K and 1 atm by applying iterative Boltzmann inversion (IBI) and the density correction method to derive the bonded and nonbonded interaction potentials. Although the CG force field is built at a single thermodynamic state point without any temperature correction, the CG model possesses a rather favorable temperature transferability in a wide temperature range of 300-800 K at P = 1 atm and a good pressure transferability to some extent in a certain pressure range from 0.1 to 30 MPa. In addition to the local conformation and local packing distribution functions, the thermodynamic properties such as the glass transition temperature and the coefficient of linear thermal expansion are predicted correctly by the CG model, and the isothermal compressibility coefficients calculated from both atomic and CG models are on the same order of magnitude. Additionally, the stress-strain behavior under compression or tension of the CG model shows a qualitative agreement with the atomistic results, and the corresponding values of the elastic modulus of the CG model at different temperatures roughly match with those of the atomistic model.

3.
J Phys Chem Lett ; 10(4): 707-714, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30694680

RESUMO

Development of the next-generation, high-energy-density, low-cost batteries will likely be fueled by sodium (Na) metal batteries because of their high capacity and the abundance of Na. However, their practical application is significantly plagued by the hyper-reactivity of Na metal, unstable solid electrolyte interphase (SEI), and dendritic Na growth, leading to continuous electrolyte decomposition, low Coulombic efficiency, large impedance, and safety concerns. Herein, we add a small amount of SnCl2 additive in a common carbonate electrolyte so that the spontaneous reaction between SnCl2 and Na metal enables in situ formation of a Na-Sn alloy layer and a compact NaCl-rich SEI. Benefitting from this design, rapid interfacial ion transfer is realized and direct exposure of Na metal to the electrolyte is prohibited, which jointly achieve a nondendritic deposition morphology and a markedly reduced voltage hysteresis in a Na/Na symmetric cell for over 500 h. The Na/SnCl2-added electrolyte/Na3V2(PO4)3 full cell exhibits high capacity retention over cycling and excellent rate capability (101 mAh/g at 10 C). This work can provide an easily scalable and cost-effective approach for developing high-performance Na-metal batteries.

4.
Adv Mater ; 31(10): e1807243, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30663171

RESUMO

All-solid-state batteries (ASSBs) with ceramic-based solid-state electrolytes (SSEs) enable high safety that is inaccessible with conventional lithium-ion batteries. Lithium metal, the ultimate anode with the highest specific capacity, also becomes available with nonflammable SSEs in ASSBs, which offers promising energy density. The rapid development of ASSBs, however, is significantly hampered by the large interfacial resistance as a matched lithium/ceramic interface that is not easy to pursue. Here, a lithium-graphite (Li-C) composite anode is fabricated, which shows a dramatic modification in wettability with garnet SSE. An intimate Li-C/garnet interface is obtained by casting Li-C composite onto garnet-type SSE, delivering an interfacial resistance as low as 11 Ω cm2 . As a comparison, pure Li/garnet interface gives a large resistance of 381 Ω cm2 . Such improvement can be ascribed to the experiment-measured increased viscosity of Li-C composite and simulation-verified limited interfacial reaction. The Li-C/garnet/Li-C symmetric cell exhibits stable plating/striping performance with small voltage hysteresis and endures a critical current density up to 1.0 mA cm-2 . The full cell paired with LiFePO4 shows stable cycle performance, comparable to the cell with liquid electrolyte. The present work demonstrates a promising strategy to develop ceramic-compatible lithium metal-based anodes and hence low-impedance ASSBs.

5.
Curr Med Sci ; 38(6): 997-1004, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30536061

RESUMO

The aim of the present study was to explore the effects of annexin A1 (ANXA1) mimetic peptide AC2-26 on sepsis-induced cardiomyocyte apoptosis in vivo and in vitro and the underlying mechanisms. In the in vivo study, a rat septic model was established by the cecal ligation and puncture (CLP). The rats were divided into control group, sepsis group and AC2-26 group. The rats in the AC2-26 group were intraperitoneally injected with AC2-26 (1 mg/kg) 2 h before CLP, and those in the control group and sepsis group were injected with the same volume of normal saline. The myocardial tissue was examined by hematoxylin and eosin (HE) staining and transmission electron microscopy (TEM). Furthermore, myocardial apoptosis was measured by terminal dUTP nick end-labeling (TUNEL) assay. In the in vitro study, H9C2 cells were cultured and divided into three groups: control group, in which cells were only given the basic culture medium; LPS group, in which cells were treated with 10 µg/mL LPS; AC2-26 group, in which cells were treated with 0.5 µmol/L AC2-26 2 h before 10 µg/mL LPS was given. The apoptosis of H9C2 cells was detected by flow cytometry. The levels of lipoxin A4 receptor (LXA4), phosphoinositide-3-kinase (PI3K) and protein kinase B (PKB or AKT) protein were measured by Western blotting, the activity of NF-κB and the level of TNF-α by ELISA and the activities of caspase-3/8 by using the caspase activity kits. The in vivo study showed that the myocardial pathological damage and myocardial ultrastructural damage were significantly alleviated and the myocardial apoptosis significantly decreased in the AC2-26 group as compared with the sepsis group (P<0.05 for all). The in vivo study revealed that the apoptosis of H9C2 cells was profoundly ameliorated in the AC2-26 group relative to the sepsis group (P<0.05). The protein expression levels of LXA4 were significantly up-regulated, and those of PI3K and AKT prominently down-regulated in the AC2-26 group when compared with those in the LPS group (P<0.05 for all). The activity of NF-κB was greatly inhibited and the level of TNF-α markedly decreased in the AC2-26 group as compared with those in the LPS group (P<0.05 for all). AC2-26 treatment also significantly suppressed the activities of caspase-3/8 in H9C2 cells. In conclusion, these findings suggest that AC2-26 may alleviate the sepsis-induced cardiomyocyte apoptosis in vivo and in vivo through the LXA4/PI3K/AKT signaling pathway.


Assuntos
Anexina A1/metabolismo , Apoptose/fisiologia , Miócitos Cardíacos/metabolismo , Peptídeos/metabolismo , Sepse/metabolismo , Transdução de Sinais/fisiologia , Animais , Regulação para Baixo/fisiologia , Lipoxinas/metabolismo , Masculino , Miocárdio/metabolismo , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/fisiologia
6.
Biochem Biophys Res Commun ; 504(1): 1-5, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-29958884

RESUMO

Lung cancer is a common malignant tumor, the cancer stem cells (CSCs) were regarded responsible for the development of cancer tissue. The effects of amiloride on lung cancer stem cells and the possible mechanism were not much investigated. In this study, human NCI-H1975 lung CSCs were selected by flow cytometry, and the effects of amiloride at different concentrations (0, 12.5, 25, 50, and 100 µmol/L) were evaluated on proliferation, migration, invasion and apoptosis of CSCs using cell counting kit-8 and Transwell migration assays as well as flow cytometry. Wstern blot analysis was performed to investigate the effect of amiloride on the level of proteins in uPA system, NF-kB pathway, and PI3K-AKT-mTOR pathway in CSCs. As a result, we found that amiloride inhibited proliferation, migration and invasion of lung CSCs, and promoted apoptosis. Further, we found that amiloride decreased levels of target proteins in the uPA system, as well as the NF-kB and PI3K-AKT-mTOR pathways. These results indicated that amiloride could inhibit proliferation, migration and invasion of lung CSCs, and promotes apoptosis, these effects may be related to decreased levels of proteins in the uPA system, the NF-kB pathway, and the PI3K-AKT-mTOR pathway.

7.
J Chromatogr A ; 1487: 83-88, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28117124

RESUMO

A new stationary phase for high performance liquid chromatography (HPLC) applications based on silica gel microspheres decorated with covalent triazine-based frameworks (CTF-SiO2) composite has been reported here. In this new hybrid material, sheet-like covalent triazine-based frameworks (CTF) were grown onto the supporting silica spheres, in order to achieve improved chromatographic separation and selectivity. The new material was characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis. The chromatographic performance and retention mechanism of the new stationary phase were investigated in reversed-phase mode and compared against standard C18 and cyano-modified silica (CN-SiO2) columns. A variety of different probe molecules were analyzed, including mono-substituted benzenes, polycyclic aromatic hydrocarbons, phenols, anilines and bases. The synergism of triazine and aromatic moieties provided several different retention mechanisms, thus improving the selectivity in the CTF-SiO2 composite. The good column packing properties of the uniform silica microspheres combined with the separation ability of the CTF frameworks make the new CTF-SiO2 material a potentially useful stationary phase for the analysis of complex samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Sílica Gel/química , Triazinas/química , Benzeno/química , Fenóis/química , Hidrocarbonetos Policíclicos Aromáticos/química , Reprodutibilidade dos Testes
8.
J Huazhong Univ Sci Technolog Med Sci ; 36(4): 576-583, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27465336

RESUMO

The aim of this study was to investigate the possible beneficial role of telmisartan in cerebral edema after traumatic brain injury (TBI) and the potential mechanisms related to the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) pyrin domain-containing 3 (NLRP3) inflammasome activation. TBI model was established by cold-induced brain injury. Male C57BL/6 mice were randomly assigned into 3, 6, 12, 24, 48 and 72 h survival groups to investigate cerebral edema development with time and received 0, 5, 10, 20 and 40 mg/kg telmisartan by oral gavage, 1 h prior to TBI to determine the efficient anti-edemic dose. The therapeutic window was identified by post-treating 30 min, 1 h, 2 h and 4 h after TBI. Blood-brain barrier (BBB) integrity, the neurological function and histological injury were assessed, at the same time, the mRNA and protein expression levels of NLRP3 inflammasome, IL-1ß and IL-18 concentrations in peri-contused brain tissue were measured 24 h post TBI. The results showed that the traumatic cerebral edema occurred from 6 h, reached the peak at 24 h and recovered to the baseline 72 h after TBI. A single oral dose of 5, 10 and 20 mg/kg telmisartan could reduce cerebral edema. Post-treatment up to 2 h effectively limited the edema development. Furthermore, prophylactic administration of telmisartan markedly inhibited BBB impairment, NLRP3, apoptotic speck-containing protein (ASC) and Caspase-1 activation, as well as IL-1ß and IL-18 maturation, subsequently improved the neurological outcomes. In conclusion, telmisartan can reduce traumatic cerebral edema by inhibiting the NLRP3 inflammasome-regulated IL-1ß and IL-18 accumulation.


Assuntos
Edema Encefálico/tratamento farmacológico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Interleucina-18/biossíntese , Interleucina-1beta/biossíntese , Proteína 3 que Contém Domínio de Pirina da Família NLR/biossíntese , Animais , Benzimidazóis/administração & dosagem , Benzoatos/administração & dosagem , Barreira Hematoencefálica/efeitos dos fármacos , Edema Encefálico/genética , Edema Encefálico/patologia , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/patologia , Caspase 1/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamassomos/efeitos adversos , Inflamassomos/genética , Masculino , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Transdução de Sinais/efeitos dos fármacos , Telmisartan
9.
Adv Mater ; 28(30): 6365-71, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27168478

RESUMO

Free-standing, high-capacity Li2 S electrodes with capacity loadings in the range from 1.5 to 3.8 mA h cm(-2) are produced by using infiltration of active materials into porous carbonized biomass sheets. The proposed electrode design can be effectively utilized for the low-cost fabrication of flexible lithium batteries with high specific energy.

10.
Angew Chem Int Ed Engl ; 55(5): 1872-5, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26680274

RESUMO

Reported herein is the first visible-light-induced formation of alkoxyl radicals from N-alkoxyphthalimides, and the Hantzsch ester as the reductant is crucial for the reaction. The selective hydrogen atom abstraction by the alkoxyl radical enables C(sp(3))-H allylation and alkenylation reactions under mild reaction conditions at room temperature. Broad substrate variations, including a structurally complexed steroid, undergo the C(sp(3))-H functionalization reaction effectively with high regio- and chemoselectivity.

11.
Sci Rep ; 5: 16012, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26531072

RESUMO

VO2/TiO2 nanosponges with easily tailored nanoarchitectures and composition were synthesized by electrostatic spray deposition as binder-free electrodes for supercapacitors. Benefiting from the unique interconnected pore network of the VO2/TiO2 electrodes and the synergistic effect of high-capacity VO2 and stable TiO2, the as-formed binder-free VO2/TiO2 electrode exhibits a high capacity of 86.2 mF cm(-2) (~548 F g(-1)) and satisfactory cyclability with 84.3% retention after 1000 cycles. This work offers an effective and facile strategy for fabricating additive-free composites as high-performance electrodes for supercapacitors.

12.
Adv Sci (Weinh) ; 2(12): 1500195, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27812221

RESUMO

S-doped carbon is investigated as a high-performance anode material for sodium-ion batteries. Due to the introduction of a high-content of S atoms, the as-obtained S-doped carbon shows an enlarged interlayer distance. As an anode, a high specific capacity of up to 303 mAh g-1 is achieved, even after 700 cycles at 0.5 A g-1.

13.
Chem Commun (Camb) ; 51(25): 5275-8, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25278239

RESUMO

We report a visible-light-induced reductive decarboxylative C(sp(3))-C(sp) bond coupling reaction to construct aryl, alkyl and silyl substituted alkynes at room temperature in organic solvents or neutral aqueous solutions. This chemoselective alkynylation was compatible with various functional groups and biomolecules, and did not affect the protein enzyme activity.


Assuntos
Alquinos/química , Anidrases Carbônicas/metabolismo , Luz , Alquilação/efeitos da radiação , Alquinos/metabolismo , Descarboxilação/efeitos da radiação , Humanos , Estrutura Molecular , Oxirredução/efeitos da radiação
14.
J Sep Sci ; 37(22): 3268-75, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25160994

RESUMO

Two new kinds of alanine-substituted calix[4]arene stationary phases of 5,11,17,23-p-tert-butyl-25,27-bis(l-alanine-methylester-N-carbonyl-methoxy)-26,28-dihyroxycalix[4]arene-bonded silica gel stationary phase (BABS4) and 5, 11, 17, 23-p-tert-butyl-25,26,27,28-tetra(l-alanine-methylester-N-carbonyl-methoxy)-calix[4]arene-bonded silica gel stationary phase (TABS4) were prepared and characterized in the present study. They were compared with each other and investigated in terms of their chromatographic performance by using polycyclic aromatic hydrocarbons, disubstituted benzene isomers, and mono-substituted benzenes as solute probes. The results indicated that both BABS4 and TABS4 exhibited multiple interactions with analytes. In addition, the commonly used Tanaka characterization protocol for the evaluation of commercially available stationary phases was applied to evaluate the properties of these two new functionalized calixarene stationary phases. The Tanaka test results were compared with Zorbax Eclipse XDB C18 and Kromasil phenyl columns, respectively. BABS4 has stronger hydrogen-bonding capacity and ion-exchange capacity than TABS4, and features weaker hydrophobicity and hydrophobic selectivity. Both of them behave similarly in stereoselectivity. Both BABS4 and TABS4 are weaker than C18 and phenyl stationary phases in hydrophobicity and hydrophobic selectivity.

15.
Adv Mater ; 26(38): 6622-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25124234

RESUMO

Novel porous ZnO/ZnFe2O4/C octahedra with hollow interiors are fabricated by a facile self-sacrificing template method involving the refluxing synthesis of hollow, metal-organic framework octahedra in solution and subsequent thermal annealing in N2 . When evaluated as an anode material for lithium-ion batteries, these porous hollow ZnO/ZnFe2O4/C octahedra exhibit significantly enhanced electrochemical performances with high rate capability, high capacity, and excellent cycling stability.

16.
ACS Appl Mater Interfaces ; 5(20): 10145-50, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24066738

RESUMO

A new hybrid nanostructure composed of mildly reduced graphene oxide (mRGO) nanosheets and homogeneous loading of amorphous FeOOH with ultrafine particles (∼2 nm) is successfully synthesized via a facile infrared irradiation approach. Surprisingly, the as-prepared FeOOH/mRGO hybrid exhibits high reversible capacity, long-term stability, and excellent rate performance, when used as an anode material for lithium-ion batteries. A high reversible capacity of 767 mA h g(-1), with a coulombic efficiency of ∼100%, can be achieved at a high current density of 1000 mA g(-1) even after 600 discharge/charge cycles. The superior electrochemical performances are attributed to the synergistic effects of the small particle size, amorphous structure, and conductive mRGO.


Assuntos
Fontes de Energia Elétrica , Compostos Férricos/química , Grafite/química , Lítio/química , Técnicas Eletroquímicas , Eletrodos , Raios Infravermelhos , Íons/química , Nanoestruturas/química , Óxidos/química
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