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1.
Int J Biol Macromol ; 273(Pt 1): 132993, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38862049

RESUMO

Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.


Assuntos
Quitosana , Condutividade Elétrica , Fontes de Energia Elétrica , Eletrólitos , Lítio , Polietilenoglicóis , Quitosana/química , Quitosana/análogos & derivados , Polietilenoglicóis/química , Lítio/química , Eletrólitos/química , Íons/química
2.
Environ Sci Pollut Res Int ; 30(40): 93227-93241, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37507562

RESUMO

This paper discusses the dynamic long- and short-term effects of bitcoin price (BTP), crude oil price (COP), and uncertainty of economic policy (EPU) on China's green bond (CGB) market, separately. Depending on the quantile autoregressive distributed lag method, the empirical results are shown that BTP and EPU exert substantial positive and negative effects on the CGB market in the long term for most circumstances, while their effects reflect not prominent in the short term. The main contributions can be summarized as follows. Given that China is the largest bitcoin mining state and a major green bond issuer, this study first explores the linkages between them. Furthermore, both long- and short-term effects are investigated from BTP, COP, and EPU to CGB, and long-term effects are dominated in the interrelationships among variables, indicating that the CGB market is mainly driven by permanent shocks. In addition, the mentioned long-term effects are deeply discussed from time- and quantile-varying aspects. This approach considers diverse situations in the bond market and various incidents that occur at various durations of time. The results underscore the significance of market participants gaining a deeper comprehension of how BTP, COP, and EPU impact green bond within varying market conditions. Implementing specific policies, such as establishing a cohesive and efficient bond market and making careful adjustments to economic policies, can be advantageous in maintaining stability within the CGB market.


Assuntos
Petróleo , Humanos , Incerteza , China , Políticas , Desenvolvimento Econômico
3.
Pest Manag Sci ; 78(3): 982-990, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34761501

RESUMO

BACKGROUND: Plant diseases caused by viruses and fungi have caused great losses to crop quality and yield. The discovery of novel and efficient antiviral and antiphytopathogenic-fungus agents is urgently needed. It is the most important pesticide innovation strategy to find active compounds from natural products. Here, glyantrypine-family alkaloids were taken as the parent structures and a series of their derivatives were designed through molecular splicing, ring expansion, and ring contraction strategies, and synthesized. The anti-tobacco mosaic virus (TMV) activities and antifungal activities of these alkaloids were systematically investigated for the first time. RESULT: The antiviral activities of compounds 7bb, 7bc, 11c, 18b, 18d, 28d, and 28e are equivalent to or better than that of ribavirin (inhibitory rates 39%, 37%, and 40% at 500 µg mL-1 for inactivation, curative, and protection activity in vivo, respectively). Compounds 18d and 28d with good antiviral activities were selected for antiviral mode of action studies, which indicated that these alkaloids could achieve good antiviral effects by inhibiting TMV particle extension during assembly. These compounds also exhibited broad-spectrum fungicidal activities. CONCLUSION: Glyantrypine-family alkaloids and their derivatives were synthesized and evaluated for anti-TMV and fungicidal activities for the first time. Compounds 18d and 28d with excellent antiviral activities and compound 7bc with remarkable fungicidal activity emerged as novel lead compounds. This study lays a foundation for the application of glyantrypine alkaloids in plant protection.


Assuntos
Alcaloides , Fungicidas Industriais , Vírus do Mosaico do Tabaco , Alcaloides/farmacologia , Antivirais/farmacologia , Desenho de Fármacos , Fungos , Fungicidas Industriais/farmacologia , Quinazolinas , Relação Estrutura-Atividade , Triptofano/análogos & derivados
4.
Nucl Med Commun ; 32(3): 227-32, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21191313

RESUMO

PURPOSE: To evaluate the effect of using tailored individual doses of radioiodine (¹³¹I) and fine tuning using low-dose antithyroid drug (ATD) in the treatment of Graves' disease, and an attempt to establish a therapeutic strategy that can keep both high rate of euthyroidism and low incidence of hypothyroidism. METHODS: The dose of radioiodine was calculated using the calculated dose formula, and low-dose ATD was used as a way of fine tuning during follow-up. The intended dose of radioiodine was modified according to the patient's age at radioiodine therapy, thyroid size, and duration of hyperthyroidism before radioiodine therapy in the study group; it was set as 2.96 MBq/g of thyroid in the control group. Twenty patients with Graves' disease were nonrandomly assigned to the control group and 98 patients with Graves' disease to the study group. The outcomes, which included euthyroidism, hypothyroidism, and persistent hyperthyroidism, were determined according to the patients' states at the end of follow-up. RESULTS: In the study group, 74 patients (75.5%) achieved the euthyroid state, six patients (6.1%) became hypothyroid, and 18 patients (18.4%) remained hyperthyroid. The rate of euthyroidism was statistically different between the study group and the control group (75.5 vs. 50%, P=0.03). Of 98 patients with Graves' disease in the study group, 19 patients were additionally treated with ATD during follow-up, and 12 patients achieved euthyroidism. In different age groups or duration of hyperthyroidism groups, the rate of euthyroidism was not statistically different among subgroups of goiter grade 1, grade 2, and grade 3 (P>0.05). Similarly, in different age groups or duration of hyperthyroidism groups, the incidence of hypothyroidism was not statistically different among subgroups of goiter grade 1, grade 2, and grade 3 (P>0.05). However, binary logistic regression analysis showed that thyroid size was associated with overtreatment and undertreatment in our study. CONCLUSION: Individual doses of radioiodine, adjusted according to the patient's age, thyroid size, and duration of hyperthyroidism, combined with low-dose ATD for some patients, 1 month or more after radioiodine therapy, was an effective method for treating Graves' disease. Our data showed that using tailored individual doses of radioiodine and fine tuning using low-dose ATD may well be a way to keep both high rate of euthyroidism and low incidence of hypothyroidism. The dose of radioiodine should be decreased a little for small goiter and increased a little for large goiter on the basis of our treatment protocol in future study.


Assuntos
Antitireóideos/uso terapêutico , Doença de Graves/tratamento farmacológico , Doença de Graves/radioterapia , Radioisótopos do Iodo/uso terapêutico , Medicina de Precisão/métodos , Doses de Radiação , Adulto , Idoso , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Análise de Regressão , Resultado do Tratamento , Adulto Jovem
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