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1.
Angew Chem Int Ed Engl ; 55(30): 8551-5, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27246874

RESUMO

All-solid-state sodium batteries, using solid electrolyte and abundant sodium resources, show great promise for safe, low-cost, and large-scale energy storage applications. The exploration of novel solid electrolytes is critical for the room temperature operation of all-solid-state Na batteries. An ideal solid electrolyte must have high ionic conductivity, hold outstanding chemical and electrochemical stability, and employ low-cost synthetic methods. Achieving the combination of these properties is a grand challenge for the synthesis of sulfide-based solid electrolytes. Design of the solid electrolyte Na3 SbS4 is described, realizing excellent air stability and an economic synthesis based on hard and soft acid and base (HSAB) theory. This new solid electrolyte also exhibits a remarkably high ionic conductivity of 1 mS cm(-1) at 25 °C and ideal compatibility with a metallic sodium anode.

2.
J Am Chem Soc ; 137(4): 1384-7, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25602621

RESUMO

In an example of stability from instability, a Li(7)P(2)S(8)I solid-state Li-ion conductor derived from ß-Li(3)PS(4) and LiI demonstrates electrochemical stability up to 10 V vs Li/Li(+). The oxidation instability of I is subverted via its incorporation into the coordinated structure. The inclusion of I also creates stability with the metallic Li anode while simultaneously enhancing the interfacial kinetics and ionic conductivity. Low-temperature membrane processability enables facile fabrication of dense membranes, making this conductor suitable for industrial adoption.

3.
Rapid Commun Mass Spectrom ; 29(15): 1437-47, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26147484

RESUMO

RATIONALE: Azilsartan medoxomil potassium (AZM) is a new antihypertensive drug introduced in the year 2011. The presence of degradation products not only affects the quality, but also the safety aspects of the drug. Thus, it is essential to develop an efficient analytical method which could be useful to selectively separate and identify the degradation products of azilsartan medoxomil potassium. METHODS: AZM was subjected to forced degradation under hydrolytic (acid, base and neutral), oxidative, photolytic and thermal stress conditions. Separation of the drug and degradation products was achieved by a liquid chromatography (LC) method using an Acquity UPLC(®) C18 CSH column with mobile phase consisting of 0.02% trifluoroacetic acid and acetonitrile using a gradient method. Identification and characterization of the degradation products was carried out using LC/electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOFMS). RESULTS: A total of five degradation products (DP 1 to DP 5) were formed under various stress conditions and their structures were proposed with the help of tandem mass spectrometry (MS/MS) experiments and accurate mass data. A common degradation product (DP 4) was observed under all the degradation conditions. DP 1, DP 2 and DP 5 were observed under acid hydrolytic conditions whereas DP 3 was observed under alkaline conditions. CONCLUSIONS: AZM was found to degrade under hydrolytic, oxidative and photolytic stress conditions. The structures of all the degradation products were proposed. The degradation pathway for the formation of degradation products was also hypothesized. A selective method was developed to quantify the drug in the presence of degradation products which is useful to monitor the quality of AZM.


Assuntos
Benzimidazóis/análise , Benzimidazóis/química , Cromatografia Líquida/métodos , Oxidiazóis/análise , Oxidiazóis/química , Espectrometria de Massas em Tandem/métodos , Hidrólise , Estresse Oxidativo
4.
J Am Chem Soc ; 136(19): 6874-7, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24730570

RESUMO

In a typical battery, the inert electrolyte functions solely as the ionic conductor without contribution to the cell capacity. Here we demonstrate that the most energy-dense Li-CF(x) battery delivers a capacity exceeding the theoretical maximum of CF(x) with a solid electrolyte of Li3PS4 (LPS) that has dual functions: as the inert electrolyte at the anode and the active component at the cathode. Such a bifunctional electrolyte reconciles both inert and active characteristics through a synergistic discharge mechanism of CF(x) and LPS. The synergy at the cathode is through LiF, the discharge product of CF(x), which activates the electrochemical discharge of LPS at a close electrochemical potential of CF(x). Therefore, the solid-state Li-CF(x) batteries output 126.6% energy beyond their theoretic limits without compromising the stability of the cell voltage. The additional energy comes from the electrochemical discharge of LPS, the inert electrolyte. This bifunctional electrolyte revolutionizes the concept of conventional batteries and opens a new avenue for the design of batteries with unprecedented energy density.

5.
Indian J Pharmacol ; 43(6): 710-3, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22144780

RESUMO

OBJECTIVE: To investigate the anticonvulsant and muscle relxant activity of ethanolic extract of stems of Dendrophthoe falcata in mice. MATERIALS AND METHODS: The ethanolic extract of stems of D. falcata (100, 300 and 500 mg/kg, p.o.) was studied for its anticonvulsant effect on maximal electroshock-induced seizures and muscle relaxant activity at the same dose level using rota rod and traction test in mice. RESULTS: Preliminary phytochemical analysis revealed presence of proteins, carbohydrates, glycosides, steroids, triterpenes, flavonoids, tannins and phenolic compounds. D. falcata ethanolic extract (DFEE) (100, 300 and 500 mg/kg, p.o.) significantly (P<0.001) inhibited seizures induced by MES, reduced the duration of Hind limb tonic extensor phase (HLTE) and a decline in motor coordination. CONCLUSION: The ethanolic extract possesses anticonvulsant activity and muscle relaxant activity.

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