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The interest in porous anodic aluminum oxide (AAO) has been rapidly growing due to its numerous applications in separation, catalysis, energy generation and storage, electronics, and sensors. From the scientific point of view, AAO is a topical interest in soft matter fields. Spatial confinement of soft matter in nanoporous media influences its structure, thermodynamics, and mobility. Embedding polymers and liquid crystals into nanopores of AAO results in a 2D nanoconfinement of these materials. This confinement affects their properties, compared to the bulk, such as phase transition temperatures and enthalpies, molecular mobility, and architecture of the crystallization. On the other hand, discotic liquid crystals (DLCs) are a promising class of soft matter for electronic applications. This is due to their ability to organize and stack themselves into columns in a hexagonal columnar mesophase, a mesophase in between the plastic crystalline and isotropic phase, driven by the overlap of the π orbitals of their aromatic core. This leads to a high charge-carrier mobility along the column axis. Further, these columns could then be considered as “molecular nanowires”. In this study, 2,3,6,7,10,11 hexakis[hexyloxy] triphenylene (HAT6), a triphenylene based DLC, was confined into nanoporous AAO membranes. The structure, dynamics and the phase behavior of the confined HAT6 were investigated by broadband dielectric spectroscopy (BDS) and differential scanning calorimetry (DSC). HAT6 was embedded into nanoporous AAO membranes by melt infiltration in the isotropic phase under argon atmosphere. The membranes have parallel aligned cylindrical nanopores, with pore diameter of 10, 20, 25, 40, 80, 120 and 180 nm. The filling degree for each sample was checked by thermogravimetric analysis (TGA) in order to ensure complete filling. Bulk HAT6 forms a hexagonal columnar phase; in between the isotropic phase above 371 K and the plastic crystalline phase below 340 K. Unlike the bulk, the confined HAT6 split the plastic crystalline-to-hexagonal columnar phase transition in two, which might be interpret as two different phase structures; close to the wall and at the pore center. Moreover, the isotropic-to-columnar transition of the confined HAT6 shifted, with decreasing pore diameter, to lower temperatures. Furthermore, pore surfaces of a series of membranes were chemically modified, resulting in a more hydrophobic pore surface than the unmodified ones. HAT6 was embedded into the modified membranes by the same aforementioned preparation. The influence of the changed host-guest-interaction, on the structure, dynamics, and the phase behavior of HAT6 confined in the modified membranes, was also investigated by BDS and DSC.
The manufacturing of NbC with Ni binder with addition of titanium carbide by using a colloidal process for blending the different powders without a milling step were investigated. The the sintering process and formation of the resulting microstructures, the phase relations and the hardness of the produced cermet materials are characterized.
Nanotechnology has been identified as a Key Enabling Technology for the European Union (Horizon 2020) and already has a wide field of applications. However, hazardous properties of nanomaterials such as their flammability and explosivity, have to be determined to ensure their sustainable development. This poster gives an overview of the current status in nanodust explosion research, standardization and european collaboration as well as highlighting current and future perspectives.
A central challenge to ensure the sustainable production and use of nanotechnologies is to understand the risks for environment, health and safety associated with this technology and resulting materials and products, and to identify and implement practical strategies to minimize these risks. Knowledge about nanotechnology-enabled processes and products and related environment, health and safety issues is growing rapidly, achieved through numerous European or national R&D programs over the last decade, but effective use of this knowledge for risk management by market actors is lagging behind.
The EC4SafeNano initiative (www.EC4SafeNano.eu) is an ongoing effort to build a European Centre for Risk Management and Safe Innovation in Nanomaterials and Nanotechnologies. EC4SafeNano aims to bridge the gap between scientific knowledge on hazard and risk, and ‘fit-for-purpose’ risk management tools and strategies supported by measurement and control methods. The consortium comprises 15 partners (INERIS (coordinator), EU-VRi, TNO, BAM, FIOH, VITO, SP, DEMOKRITOS, TECNALIA, Health and Safety Executive, NRCWE, Paris Lodron University Salzburg, Université Libre de Bruxelles, University of Birmingham and ENEA) from 11 European Member States with significant expertise on risk assessment and management, who already provide knowledge and technical services to public and private organizations, to industry and to public authorities and regulatory bodies.
The overall objective of the EC4SafeNano project is to develop a distributed Centre of European Organisations offering services for Risk Management and Safe Innovation for Nanomaterials & Nanotechnologies. The Centre will be structured as a hub-based network of organizations managed by a core group of public-oriented bodies providing risk management and safe innovation support to all stakeholders. It will be operated with the support of Associated Partners so as to expand its capabilities, resources and services. It will interact with existing platforms and centres of excellence in nanosafety and foster the organization or development of national hubs mirroring the European hub. The Centre will seek financial support from stakeholders and service users to sustain the services in the longer term.
The operational objectives of the project involve understanding and mapping the needs of the various stakeholders (private and public). It will identify the resources and capabilities and develop a range of harmonized services required to meet these needs. The construction of the centre will include putting in place and implementing processes to deliver and update services, to test and benchmark services, to evaluate the governance of the Centre, and developing a business plan to ensure self-sufficiency of the Centre beyond the project lifetime.
A cornerstone of the project is to build a community for risk management and safe innovation for nanotechnology. Interested persons or organisations are invited to join this initiative as registered stakeholders or Associated Partners, to engage in focus networks and to help shape the future Centre. The poster will present the EC4SafeNano initiative and will detail the role of registered stakeholders and Associated Partners.
The Federal Institute for Materials Research and Testing (BAM) and the Institute for Machine Tools and Factory Management (IWF) of the Technical University Berlin analyzed the suitability of various NbC types in comparison to tungsten carbide (WC) for use as a tool in cutting processes. The focus was placed on the optimization of the functional profile of NbC-based cutting materials with reproducible industrial production.
Polyurethanes (PU) are formed by polyaddition reaction between diols and diisocyantes. They can be formed utilizing three building blocks, namely a polyol or long-chain diol, a chain extender or short-chain diol, and a diisocyanate. The derived multi-phase block copolymer has thermoplastic properties and is called thermoplastic PU (TPU). This modular approach allows for a variety of alternations yielding a broad range of structural properties and applications. TPUs are based on three main classes of polyols, i.e. polyethers, polyesters, and polycaprolactones. With these different polyols and the ability of changing the ratio of building blocks a variety of material properties can be obtained thus TPUs find numerous applications in e.g. lightweight construction1, insulation, flame retardants, lacquer and glue, as well as medicine.
Linear, isocyanate terminated, polyurethane prepolymers prepared from non-equivalent amounts of diisocyanate such as methylene diphenyl diisocyanate (MDI) attached to a polyol are widely used as precursors of the correspondent polymers. Chain-extending reactions with low molecular weight compounds bearing different amounts of active hydrogens enable both linear and crosslinked polyurethane to be formed.
Due to TPUs being used in a broad range of applications facing a variety of stress (e.g. mechanical, hydrolytic, thermal, radiative/UV, as well as its combinations) the complexity of possible degradation mechanism is high. A functional group derived from degradation of the bulk matrix can be detected utilizing a suited fluorogenic sensor molecule. There are several fluorogenic dyes known for the application as sensor for amine groups e.g. fluorescamine, pyrylium dyes, deriving a fluorescent signal upon reaction.
Nanoparticles (NPs) have potential applications in medical diagnostics, imaging, drug delivery and other kinds of therapy. Furthermore, studies concerning nanoparticle uptake by cells are important for risk assessment. Size, shape and surface modification of the NPs determine the uptake rate and pathway into the cells, and therefore impact specific cell components and processes. Understanding the different uptake mechanisms and involved processes require sub-cellular resolution to determine, for example, whether the nanoparticles are reaching the nucleus. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is an established quantitative multi-elemental analysis and mapping technique. However, sub-cellular imaging has traditionally been challenging to achieve due to a lack of sensitivity at small laser spots. But now novel laser ablation systems with improved sensitivity and washout time allow imaging at high lateral resolution with spot sizes down to 1 µm.
Here LA-ICP-MS was applied for the imaging of individual fibroblast cells to study the uptake and intracellular processing of metal-containing NPs. To indicate cell morphology the local distribution of naturally occurring elements in cells like P and Zn was measured, too. Our results show that LA-ICP-MS can be used to localise nanoparticle aggregates within cellular compartments. The studied NPs accumulate in the perinuclear region in the course of intracellular processing, but do not enter the cell nucleus. The uptake efficiency depends strongly on the physico-chemical properties of the nanostructures as well as on the incubation conditions like concentration and incubation time. The potential of LA-ICP-MS for analysis at single cell level will be demonstrated.
Several restoration projects of stained-glass windows have been performed in Poland since 2010.Chemical analysis of glass samples was performed with SEM/EDX on a FEI ESEM-XL 30, (EDX-EDAX) and with Micro-XRF (M4 Tornado, Bruker).The chemical composition of medieval glass samples and of glass samples of the 19th Century have been determined.
Scanning Electron Microscopy (SEM) or Transmission Electron Microscopy (TEM) ? This is a question, nowadays discussed in EM labs of research and industry involved in the characterization and metrology of nanoparticles. The Scanning principle is adapted to TEM, the Transmission mode is adapted to Ultra High Resolution SEM. Can modern SEM replace TEM, reach atomic resolution even without Cs corrector or nm lateral resolution for energydispersive X-ray spectroscopy (EDX)?
Due to the development of a New Cold Field Emission (NCFE) electron source Hitachi SEMs SU9000 and SU8200 can deliver routinely sub-nm image resolution and EDX mappings at very high count rates and a lateral EDX resolution of a few nm. A TiO2 sample provided by BAM was analysed at 30kV using low kV STEM – simultaneously with the Through-the-lens (TTL) SE detector, the Bright Field transmitted and Dark Field transmitted signals. By this method a pixel precise information of the particles surface using SE, its chemical nature using DF-STEM and its crystalline structure using Bright Field signal is given in one 40sec scan. The advantage of this observation mode compared to Ultra Low Voltage imaging is outlined.