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1. Formation and ripening of SrTiO3 nanocrystals on SiO2

   https://doi.org/10.1063/5.0273570  

   Chinna_Kannu, L_K; Marandu, M_H; Liu, R.; Hernandez, J_M; Evans, P_G (July 2025, APL Materials)

   The crystallization of complex oxide thin films on amorphous substrates presents a significant challenge because of the lack of long-range order in these substrates and the subsequent difficulty in controlling crystal growth. Nanocrystals with similar crystal structure have the potential to serve as nucleation sites for crystallization and can facilitate this integration. Isolated nanocrystals of strontium titanate (SrTiO3) can be produced on amorphous SiO2 surfaces through crystallization and ripening of initially amorphous layers of SrTiO3. The resulting SrTiO3 nanocrystals exhibit characteristic lateral radii ranging from tens to hundreds of nm and a consistent average height of 1–2 nm across this range. The area density and mean radii of the nanocrystals can be selected by adjusting the deposition and heating parameters, including the amount of deposited SrTiO3 and the heating duration. The heating-time dependence of the area density and mean radii of the nanocrystals is consistent with predictions based on Ostwald ripening kinetics. The selection of these parameters facilitates the use of SrTiO3 nanocrystals as nucleation sites to crystallize the subsequently deposited layer. 

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2. On formation and breakup of jets during droplet impact on oscillating substrates

   https://doi.org/10.1007/s00348-024-03911-z  

   Potnis, Aditya; Saha, Abhishek (December 2024, Experiments in Fluids)

   Abstract Droplet impact on substrates is the cornerstone of several processes relevant to many industrial applications. Imposing substrate oscillation modifies the impact dynamics and can, therefore, be used to control the ensuing heat, mass, and energy transfer between the substrate and the impacting droplet. Previous research has shown that substrate oscillation strongly influences the spreading behavior of the droplet. In this study, we extend this understanding to examine how substrate oscillations can further modulate the retraction dynamics of the droplet, consequently affecting its long-term behavior, with a particular focus on induced jetting and subsequent breakup. We systematically examine the breakup of jets formed by the recoiling droplet through experimental investigations across a range of oscillation frequencies and amplitudes. Our findings reveal two distinct jet breakup modes: early and late, each governed by different time scales. Subsequently, we present a mechanistic description of the jetting process. Furthermore, we derive a simple scaling analysis based on energy balance to identify the critical condition required for jet breakup. Finally, we compare the experimental data with the scaling analyses to show its efficacy. 

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3. Stain Formation on Deforming Inelastic Cloth

   https://doi.org/10.1109/TVCG.2017.2789203  

   Wang, Xiaojun; Liu, Shiguang; Tong, Yiying (December 2018, IEEE Transactions on Visualization and Computer Graphics)
4. Effect of metal chlorides on glucose mutarotation and possible implications on humin formation

   https://doi.org/10.1039/C8RE00233A  

   Ramesh, Pranav; Kritikos, Athanasios; Tsilomelekis, George (February 2019, Reaction Chemistry & Engineering)

   An in situ Raman spectroscopic kinetic study of the glucose mutarotation reaction is presented herein. The effect of metal chlorides on the ease of the ring opening process is discussed. It is shown that SnCl 4 facilitates the mutarotation process towards the β-anomer extremely fast, while CrCl 3 appears to promote the formation of the α-anomer of glucose. The infrared spectra of humins prepared in different Lewis acids underscore the possibility of multiple reaction pathways. 

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5. Neuronal Growth and Formation of Neuron Networks on Directional Surfaces

   https://doi.org/10.3390/biomimetics6020041  

   Yurchenko, Ilya; Farwell, Matthew; Brady, Donovan D.; Staii, Cristian (June 2021, Biomimetics)

   The formation of neuron networks is a process of fundamental importance for understanding the development of the nervous system and for creating biomimetic devices for tissue engineering and neural repair. The basic process that controls the network formation is the growth of an axon from the cell body and its extension towards target neurons. Axonal growth is directed by environmental stimuli that include intercellular interactions, biochemical cues, and the mechanical and geometrical properties of the growth substrate. Despite significant recent progress, the steering of the growing axon remains poorly understood. In this paper, we develop a model of axonal motility, which incorporates substrate-geometry sensing. We combine experimental data with theoretical analysis to measure the parameters that describe axonal growth on micropatterned surfaces: diffusion (cell motility) coefficients, speed and angular distributions, and cell-substrate interactions. Experiments performed on neurons treated with inhibitors for microtubules (Taxol) and actin filaments (Y-27632) indicate that cytoskeletal dynamics play a critical role in the steering mechanism. Our results demonstrate that axons follow geometrical patterns through a contact-guidance mechanism, in which geometrical patterns impart high traction forces to the growth cone. These results have important implications for bioengineering novel substrates to guide neuronal growth and promote nerve repair. 

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