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Focus seminars In addition to the summer schools and the annual retreats, more focused meetings bring together young members and PIs of the CRC-TR from closely interacting subprojects and, where appropriate, external guests. These smaller scale seminars are organized on a regular basis. The participating groups present their projects to each other and discuss further opportunity of collaboration. The focused meeting provide the attendees with an opportunity for advanced training and exchange and for expanding their scientific network. Every student in the IRTG is be expected to participate in the organization of at least one such event during the time of the thesis. The CRC-TR office and the PIs of the participating sub-projects also provide support for the organization of these activities.

Complementary training To complement the solid scientific preparation of the members of the CRC-TR, and to prepare the young members for a job in the industry or academia, transferable skills courses and career development initiatives are organized within the framework of the IRTG in cooperation with the other graduate schools in Mainz (MAINZ, MPGC, the center for computational science) and Ingenium in Darmstadt in order to provide an integrated complementary training offer. The topics mainly covered within the transferable skill umbrella range from ‘project management’ to ‘intercultural communication’, from ‘scientific writing’ to ‘oral presentation skills’, from ‘scientific data management’ to ‘good scientific practice’. Further career development initiatives include discussions with guests from the industry (i.e., chemical companies, publishing companies, patent lawyers etc.) as well as excursions to external companies of interest. The students of the IRTG choose the topics of their transferable skill courses themselves, according to their interests, and […]

Research stay abroad This activity is meant to provide further advanced training and to foster the internationalization of the education of the PhD students of the CRC-TR, as well as opening opportunities for the corresponding CRC-TR subproject to establish new links and collaborations abroad. Students of the IRTG are strongly encouraged to spend up to 6 months in a renowned lab abroad, where they will have the possibility to acquire more independence, learn new skills, create/strengthen collaborations and expand their personal scientific network. The research stay abroad is fully funded by the IRTG. The choice of the external lab is made individually by the students together with their advisor.

Student initiatives The IRTG encourages doctoral students to pursue own ideas, take own initiatives, and to prepare and submit corresponding short proposals. This aims to foster student’s independence and scientific vision of their field of research, and also help them to gain first experiences with preparing proposals in order to obtain support for their research. Two specific sets of student initiatives described below are supported explicitly. Applications for research assistants The IRTG encourages the doctoral students to apply for undergraduate student research assistants. This will help them to develop their supervision skills. Applications to fund an undergraduate student research assistant in connection with a project are considered by the IRTG once per year. Groups of students and postdoctoral researchers need to prepare such projects on topics of shared interest. Each project will be presented to the assembly of students and discussed, e.g. after one of the students’ seminars. In addition […]

Short term doctoral fellowships To allow for flexibility in the recruitment process, a pool of 31 months of short-term doctoral fellowships per year for national and international PhD students has been established. Each fellowship provides funding for a doctoral student for up to 1 year maximum. The doctoral fellowships will serve two purposes: First, they will allow PIs to accept applications of excellent candidates even if a position is not available immediately. Second, they will be used to promote international exchange. Graduate students from abroad can get a fellowship to visit the CRC-TR for a period of up to one year.

Project C1: Using molecular fields to bridge between particle and continuum representations of macromolecular systems In this project, we explore the potential of so-called “molecular field” theories to bridge between particle-based and continuum representations of macromolecular materials. Regarding static equilibrium properties, they canbe linked to particle models via the well-established self-consistent field theory, a sophisticated density functional theory for polymers, and extensions thereof. Our goal is to design systematic mapping procedures for dynamic properties, i.e., devising dynamic density functionals (DDFs) of comparable quality. The work in the second funding period was motivated by a finding at the end of the first funding period, where we had identified severe shortcomings of the previously available DDF models. The central quantities in these DDF models are nonlocal mobility functions describing the response of the monomer current to a spatially varying field. We have devised a bottom-up method to construct these mobility functions from […]

Project C3: Spinodal decomposition of polymer-solvent systems We consider the phase separation of dynamically asymmetric mixtures, in particular polymer solutions, after a sudden quench. Crucial aspects are (i) hydrodynamic momentum transport and (ii) the lack of time-scale separation between molecular relaxation and coarsening. This gives rise to complex dynamical processes such as the transient formation of network-like structures of the slow-component-rich phase, its volume shrinking, and lack of dynamic self-similarity, which are frequently summarized under the term viscoelastic phase separation. The relevant length and time scales of the physical phenomena are too large for microscopic (all atom) simulations. Alternative mesoscopic models based on a bead-spring description of polymer chains coupled to a hydrodynamic background, i.e., the Navier-Stokes equations for the solvent, allow to capture the basic physical principles but they are still computationally demanding. Therefore, macroscopic (two-fluid) models have been proposed in the literature which involve only averaged field quantities […]

Project C4 (Completed): Coarse-graining frequency-dependent phenomena and memory in colloidal systems Electrostatic interactions can strongly influence the behavior of macromolecular systems. A particular challenge for their prediction is the accurate, albeit computationally tractable, handling of the influence of water dipoles on the potentials. To address this challenge, we develop an efficient and accurate numerical framework for nonlocal electrostatics of large molecular systems. An improved understanding of the influence of water structure on electrostatics has far-reaching applications: the results of the project can, in principle, be used wherever implicit water models are desired, but where a simple structureless continuum is insufficiently accurate. This project has ended in June 2018.

Project C5: Adaptive hybrid multiscale simulations of soft matter fluids We develop and analyse efficient, hybrid multiscale methods that bridge the continuum-particle gap by combining a discontinuous Galerkin method for the macroscopic model with molecular dynamics. In the second funding period we have focused on the description of non-Newtonian fluids, particularly polymer melts, in sim- ple and complex geometries as well as on theoretical convergence analysis of numerical schemes taking multiscale effects into account. Building on these results we will study the flow behaviour of polymer mixtures and develop methods to separate polymers with similar molecular masses based on differences in rheological properties (WP1). Applying a probabilistic concept of solutions, we will extend our convergence analysis to these non-Newtonian systems (WP3) and investigate effects of uncertainty with machine learning techniques (WP4). In the final funding period, we would also like to expand the scope of our project to a novel, […]

Project C6 (Completed): Linking hydrodynamics and microscopic models of wet active matter with anisotropic particles The goal of this project is to develop a systematic, quantitative coarse-graining approach for a class of inherently non-equilibrium systems, namely suspensions of self-propelled particles. We link particle based models with effective hydrodynamic models within a multiscale framework based on sequential coupling and parameter passing. To this end, we combine microscopic Stokesian dynamics simulations with a mesoscopic kinetic model coupled to the macroscopic Stokes equation, and, in a second step, derive an effective hydrodynamic description in terms of particle density, polarization and nematic order parameter profiles. The multiscale scheme is applied to systems of self-propelled rod-like magnetic colloids suspended in a fluid. This is motivated by recent experiments on magnetotactic bacteria, which have shown that the interplay of internal drive (self-propulsion, mutual interactions) and external drive (magnetic field, oxygen gradient) in these systems leads to […]