蔗糖对钾长石水热分解过程的相变影响机理

在氧化钙与钾长石的水热分解反应中加入蔗糖,以改善水热产物雪硅钙石的吸附性能。以氧化钾的提取率作为衡量标准,研究蔗糖浓度对钾长石分解速率的影响,阐明蔗糖对钾长石水热分解过程的相变影响机理。结果表明,当蔗糖与氧化钙的摩尔比为0.1:1时,氧化钾的提取率为83.83%,随着蔗糖浓度的增加,钾长石的分解被抑制。反应体系黏度的增加和水热过程中钙络合物的形成是抑制钾长石分解的主要原因。此外,从微观形貌角度解释蔗糖改性雪硅钙石对亚甲基蓝吸附能力的增强机理。

Corundum dissolution in concentrated sodium hydroxide solution

The corundum(α-alumina) core has been considered as a suitable candidate for investment casting of hollow, high pressure turbine engine airfoils due to its excellent properties. However, the efficiency of removing alumina cores in concentrated caustic solution cannot meet the needs of industrial production. In this paper, the effects of temperature and initial solution concentration on dissolution of α-alumina were studied by the classical weight-loss method. The fractal kinetic model was developed in order to describe α-alumina dissolution, assuming that the nonporous particles shrank during reaction process. The results show that the dissolution rate increases with increasing reaction temperature and initial solution concentration. Especially, the initial solution concentration has a significant influence on α-alumina dissolution rate at a higher reaction temperature. The activation energies decrease with increasing initial solution concentration, and the chemical reaction is the rate-controlling step.

Inflammation and Carcinogenesis

We consider that inflammatory substances play an important role in the carcinogenesis process. In the process, cytokines and growth factor secreted by cells can actively recruit immune cells in the carcinogenesis microenvironment, further, promote carcinogenesis progression. The carcinogenesis microenvironment even subverted the immune system, moreover, enhanced the carcinogenesis through immune suppressive mechanisms within the carcinogenesis microenvironment.

半离子C-F键在钾离子电池碳负极中诱导快速离子储存和电子转移

氟(F)杂原子功能化的碳负极可以形成更多的缺陷位点,从而有效提高钾的存储容量.然而,提高电化学性能的机制尚不清楚,尤其是对何种C-F键深入影响钾储存性能仍缺乏基本认识.本文报道了一系列F掺杂的碳,并证明了C-F是半离子键而不是离子键;碳化温度对缺陷程度有显著影响.并且,高比例半离子C-F键诱导的丰富缺陷可以作为活性位点来吸附大量与电容行为相关的钾离子,不仅有利于长循环寿命,而且提升了在高电流密度下的倍率容量.密度泛函理论计算证实半离子C-F键的存在可以提高碳基体对钾离子的吸附能力并同时提高电子电导率,有利于高容量和倍率.此外,通过耦合半离子C-F键和吡啶N键,钾吸附能和电导率被进一步提升,这使得半电池实现了优异的容量(245.2 mA h g^(-1))和倍率,并且组装的全电池具有高能量密度(143.9 W h kg^(-1)).

Recent progress in application of cobalt-based compounds as anode materials for high-performance potassium-ion batteries

Potassium-ion batteries(KIBs)are regarded as one of the most promising replacements for lithium-ion batteries because of their low cost and high performance.Exploring suitable anode materials to stably and effectively store potassium is critical for the development of KIBs.Given their high theoretical specific capacity,cobalt-based compounds have been extensively investigated as an anode material in recent years;however,specific reviews summarizing the research progress in the application of cobaltbased compounds as anode materials for high-performance KIBs are lacking.Consequently,this review systematically summarizes the recent states of cobalt-based anode materials in KIBs starting at the potassium storage mechanism,followed by strategies and applications to improve the electrochemical performance.The current challenges are also discussed,and corresponding prospects are proposed.This work may facilitate the realization of various applications of cobalt-based compound anodes for highperformance rechargeable batteries and is expected to provide some guidance for developing other metal-based compounds for KIBs anodes.