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Seminar chair is Professor Andrejs Cēbers. Seminar organizing committee includes Dārta Antāne, Ivars Driķis and Guntars Kitenbergs., This abstract book is made for the seminar "Magnetic Soft Matter", held on February 11, 2021. It is organized by the MMML lab (Lab of Magnetic Soft Materials) of the University of Latvia as a part of the 79th International Scientific Conference of the University of Latvia. It includes topical contributions from researchers working on various magnetic soft matter problems., We acknowledge the funding from the Latvian Council of Science Fundamental and Applied Research Project ”Biologically inspired models of active matter driven by electromagnetic field” (lzp-2020/1-0149).

Advisors: Prof. Andrejs Cēbers (University of Latvia) & Prof. Régine Perzynski (University of Pierre and Marie Curie), in English: Magnetic field induced instabilities of magnetic fluids in microfluidic environment are investigated experimentally using electrically stabilized water-based magnetic nanocolloids. Magnetic micro-convection, observed at a miscible interface in a Hele-Shaw cell in homogeneous field, is studied quantitatively and is compared with theoretical predictions and numerical simulations. An application towards mixing enhancement in microfluidics is considered. The micro-convection study reveals a large effective nanoparticle diffusion coefficient, which mostly arises from a flow induced by the density difference between the miscible fluids. Experiments with magnetic drops, formed by phase separation, show that in a precessing field at magic angle, the drops undergo two shape instabilities as in a rotating field except the initial shape deformation. - - - ANOTĀCIJA LATVIEŠU VALODĀ: Eksperimentāli pētītas magnētiskā lauka izraisītas magnētisko šķidrumu nestabilitātes mikrofluidikā, lietojot elektriski stabilizētus magnētiskus nanokoloīdus uz ūdens bāzes. Magnētiskā mikro-konvekcija, ko novēro homogēnā laukā uz sajaukties spējīgas robežas Hele-Šou šūnā, tiek pētīta kvantitatīvi un tiek salīdzināta ar teorētiskajām sakarībām un skaitliskajiem aprēķiniem. Ir apskatīts pielietojums maisīšanas uzlabošanai mikrofluidikā. Mikro-konvekcijas pētījums atklāj lielu nanodaļiņu efektīvo difūzijas koeficientu, kas galvenokārt rodas no šķidrumu blīvumu atšķirību radītās plūsmas. Eksperimenti ar magnētiskiem pilieniem, kas rodas fāžu atdalīšanās procesā, rāda, ka pilieniem precesējošā laukā pie maģiskā leņķa, gluži kā rotējoša lauka gadījumā, novērojamas divas formas nestabilitātes, izņemot sākotnējo formas deformāciju., European Social Fund project Nr.2013/0028/1DP/1.1.1.2.0/13/APIA/VIAA/054 Scholarship for co-tutelle studies from the French Embassy in Riga, Latvia