Role of Aluminum and Lithium in Mitigating Alkali-Silica Reaction—A Review

Effective mitigation of alkali-silica reaction (ASR) is critical for producing durable concrete. The use of alumina-rich supplementary cementitious materials (SCMs) and chemical admixtures such as lithium salts to prevent expansion caused by ASR was first reported 70 years ago, shortly after the discovery of ASR in 1940s. Despite numerous investigations, the understanding of the mechanisms of Al and Li for mitigating ASR remain partially inexplicit in the case of Al, and hardly understood in the case of Li. This paper reviews the available information on the effect of Al and Li on ASR expansion, the influencing factors, possible mechanisms and limitations. The role of Al in mitigating ASR is likely related to the reduction of dissolution rate of reactive silica. Moreover, the presence of Al may alter the structure of crystalline ASR products to zeolite or its precursor, but such effect seems to be not that significant at ambient conditions due to the slow kinetics of zeolite formation. Several mechanisms for the lithium salts in mitigating ASR have been proposed, but most of them are not conclusive primarily due to the lack of knowledge about the formed reaction products. Combination of Al-rich SCMs and lithium salts may be used as an economic solution for ASR mitigation, although systematic studies are necessary prior to the applications.

Impacts of Lithium Salts on the Thermal and Mechanical Characteristics in the Lithiated PEO/LAGP Composite Electrolytes

Lithium batteries utilizing solid-state electrolytes have the potential to alleviate their safety hazard, reduce packaging volume, and enable flexible design. Polymer/ceramic composite electrolytes (CPE) are more attractive because the combination is capable of remedying and/or transcending individual constituent’ properties. Recently, we fabricated a series of free-standing composite electrolyte membranes consisting of Li1.4Al0.4Ge1.6(PO4)3 (LAGP), polyethylene oxide (PEO), and lithium salts. In this study, we characterized thermal and mechanical properties of the CPEs with two representative lithium salts, i.e., lithium boron fluoride (LiBF4) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). We found that the type of lithium salt can prevail the LAGP ceramic loadings on altering the key properties. It is observed that LiTFSI, compared with LiBF4, causes more significant reduction in terms of the crystallinity of PEO, melting transition, and mechanical strengths. The differences in these aspects can be ascribed to the interactions between the polymer matrix and anions in lithium salt.

Estimation of the effect of lithium salts on cytokine production by blood cells in in vitro experiments

Aim. To study the effects of lithium salts on production of cytokines by immunocompetent cells in the whole-blood culture of patients with alcohol dependence and affective disorders.Materials and methods. The study materials were blood samples from 25 patients with alcohol dependence (AD) and 12 patients with bipolar disorder (BD). Blood diluted 1:1 with complete RPMI-1640 medium (Gibco, UK) was added to the wells of the culture plate, then new lithium salts (succinate, fumarate, pyruvate, ascorbate) and a reference salt – lithium carbonate at a final concentration of 1.2 mmol / l per lithium ion – were added. In parallel, control samples without lithium salts were tested; the samples were incubated for a day. The concentration of cytokines (interferon (IFN) γ, interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-17A, tumor necrosis factor (TNF) α) was determined in the culture supernatants on the MAGPIX multiplex analyzer (Luminex, USA) (Center for Collective Use “Medical Genomics”, Tomsk NRMC) using the Human Cytokine / Chemokine Magnetic Bead Panel (Merck, Germany).Results. All lithium salts had a unidirectional effect on the production of cytokines by immunocompetent cells (ICC), except for lithium ascorbate and IL-8. The concentrations of cytokines in the supernatants of loaded and control samples (spontaneous production) were comparable, which indicates an absence of stimulating or suppressing effects of salts on the functional activity of ICC under the experimental conditions. The effect of lithium ascorbate as an IL-8 inducer was detected: the production of IL-8 induced by lithium ascorbate was 2.3–2.5 times higher than its spontaneous production.Conclusion. The obtained results, as well as the previously revealed antioxidant and cytoprotective properties of new lithium salts, confirmed that they are promising for development of pharmacological agents with combined action.

Examining the Deliquescence of Lithium Salts and Those of Other Alkali Metals Through a Range of Humidity

It is well known that lithium chloride is able to extract moisture from the ambient air. Our research in this area has examined a variety of lithium salts for their ability to do so, as well as their counterparts containing sodium and potassium. Additionally, we have made and utilized chambers that allow us to examine deliquescence of these salts in conditions of various humidity. We will present the results, and how these experiments can be adapted to the teaching of laboratory courses.