The assembly of ancient informational polymers from nucleotide precursors is the central challenge of life's origin on our planet. Among the possible solutions, dry polymerization of 3’,5’‐cyclic guanosine monophosphate (3’,5’‐cGMP) has been proposed as a candidate to create oligonucleotides of 15–20 units in length. However, the reported sensitivity of the reaction to the presence of cations raised questions of whether this chemistry could be relevant in a geological context. The experiments in this study show that the presence of cations is not restrictive as long as the reaction is conducted in an acidic environment, in contrast to previous reports that suggested optimal conditions at pH 9.

Previous studies on the polymerization of 3',5' cyclic guanosine monophosphate (cGMP) demonstrated the potential of the compound in the abiotic generation of the first oligonucleotide sequences on the early Earth. These experiments were conducted under idealized laboratory conditions, which logically raises the question whether the same chemistry could take place in the harsh environment present on our planet in its earliest days. In the current study, we focus on the mineralogical context of this chemistry and show that numerous, but not all, common minerals assumed to be present on the early Earth could host the polymerization of H-form 3',5' cGMP. In particular, we have found that quartz varieties are especially suitable for this purpose, similar to andalusite, amphibole or micas. On the contrary, olivine, calcite, and serpentine-group minerals interfere with the studied polymerization chemistry. Our results show that crystallization on mineral surfaces, which is mainly a diffusion controlled process, determines the ability of 3',5' cGMP to polymerize. The observation that numerous amorphous and crystalline SiO 2 forms are compatible with the oligomerization chemistry suggests that the process could commonly occur in a wide range of primordial environments allowing for crystallization of the cyclic monomers from a dropping solution.

An automotive friction brake pad is a complex system consisting of several components with unique and balanced properties related to operation conditions. There are efforts to develop brake pads with longer lifetime and better friction performance and wear properties. Those properties are related to composition of the pads, and therefore, new materials are being evolved. Tuning the friction and wear properties can be achieved with the selection of a functional filler and optimizing its amount in a formulation of friction brake pad. Laboratory-developed and laboratory-prepared nanocomposite material kaolin/TiO2 (KATI) has been introduced to formulation of the commercially available automotive low-steel brake pad. Kaolin was utilized as a matrix for anchoring TiO2 nanoparticles. New unused pads and pads after AK master, a standard dynamometer testing procedure of friction performance, were investigated using light and scanning electron microscopy providing information on the structure and its changes after the friction processes. Moreover, MTK wear test was used to compare wear rate of the newly developed pad with the reference low-steel pad. Improved durability of the brake pad formulation has been observed together with sufficient friction performance. Microscopic analysis shown homogenous distribution of the KATI nanocomposite in the friction layer. From the obtained results, it can be assumed that the new formulation is promising regarding to the life cycle of the pads and reduction of wear rate and thus potential production of wear particulate emissions.

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