List of questions

  • 4505

    4378: We are looking for process that produce small fine particles of collagen, form threads, and lower the molecular weight of the collagen without degrading the material into gelatin? Is there a any polymer or coating that has similar characteristics and functions as collagen?

    4381: How does the manufacturing process effect level of residual monomers that remain in polymeric materials and are the levels vary depending upon type of polymer?

    4378: • What processes can be used to produce a fine collagen powder that can be sprayed without clogging the sprayer nozzle? Is there a way of controlling the particle size of the collagen?
    • By crosslinking collagen can produce a stronger material, is there a process that can turn that collagen sheet into a strong thread?
    • Is there a process whereby the molecular weight of collagen can be controlled?
    Our collagen is animal derived product. We’re currently use collagen as a coating on polyester graft. The function of the collagen is self-healing and promoting ingrowth. Due the restriction of new regulation in medical devices, derived animal product has to replace with manmade materials.

    4381: The residual monomers remain in the materials and these monomers are released in the extracts during the extractable & leachable analysis of the polymeric materials or the final finished device.
    • How do the manufacturing processes (such as heating/cooling rate and temperature, crystallinity of the materials) affect the level of residual monomers that remain in the polymeric materials?
    • Does the residual monomer levels significantly vary with the type of polymer (i.e., polypropylene vs nylon)?

  • 4508

    4384: We are looking for an effective non-drug antimicrobial coating or ingredients to coat the exterior of our PTFE grafts.

    4387: What are the latest advances in modifying biomaterial surfaces for blood compatibility?

    4384: The current antimicrobial technologies available for grafts are:
    • Non-releasing (passive) coatings such as cationic polymer-dextran, chitosan, polyethylenimine, cationic polyurethane and acrylates.
    • Releasing based (active) coatings, including metal complexes and antibiotics, such as chlorohexidine/Ag salt, triclosan/AgNO3 or surface coatings doped with vancomycin or amoxicillin.
    • Peptide mimetic, such as steroid based or Apolipoprotein E, small peptide.
    • Or combination of a, b and c to coat the devices.
    We would like to discuss any potential collaboration in this area including research projects or start-up technology.

    4387: • For surface coating of vascular grafts, including those for abdominal aortic aneurysms?
    • For restenosis prevention in coronary stents with or without added drug?
    • In other coronary, peripheral-vascular or neurovascular applications?

Hitachi Powergrids Research
  • 4354

    Ramanspectroscopy for evaluation of cellulose depolymerization degree

    The electrical insulation of power transformers, which are a key component in every power transmission grid, is made of cellulose. The degree of depolarization of the cellulose fibers is an important quality criterium. The are recent publication about Raman spectroscopy of cellulose fibers. We would like to understand if Raman spectroscopy has the potential to measure/monitor the progress of depolarization as well as what kind of equipment/set-up would be needed.

Hitachi-ABB Power Grids
  • 4338

    Are novel/accurate there mechanical models to describe the stress relaxation/creep of cellulose based materials with respect to temperature and moisture

    Cellulose-based are used as insulation materials for high voltage components. long term mechanical forces are applied over time at different temperatures and moisture content. It would be interesting to be able to foresee, by using dedicated models, the deformation over time of the cellulose based components.

MG Sustainable Engineering AB
  • 4350

    What is an adequate method for encapsulation of silicon cells in C-PVT collectors?

    Solar PV panels never reach temperatures above 100C.
    Concentrating PVT (photovoltaic-thermal) solar collectors can reach temperatures of 150C or higher. This way, EVA is not an option for C-PVT.
    PVT collectors in order to be competitive should use standard cells due to cost.
    What is an adequate method for encapsulation of silicon cells in C-PVT collectors?
    Note: The encapsulation needs to be cheap (including assembly cost), ensure electrical resistivity, allow heat transfer, resist UV and high durability.

  • 4413

    How to understand the crack mechanism at high temperatures on cast Inconel (713C)?

    Cracks has been formed on cast Inconel (713C) at high temperature with present of exhaust environment mainly containing O2, CO2, H2O, Nox and urea. TEM-analysis show that cracks are associated with a Ti-Nb-Mo-S-P containing phase. There is nitrogen in cracks, but nitrogen has not diffused into the Inconel 713C material. In addition to nitrogen, carbon also coexists in the crack. There is no metal atom associated with the carbon or nitrogen in the cracks. The nitrogen rich region in the crack does not show any crystallinity. It seems that the nitrogen enrichment is ingress of urea due to capillary effect in the cracks. We intend to understand the crack mechanism and more specifically we wonder: The environment at crack-tips and the start-region are different concerning the oxygen partial, gas or liquid form (urea could not be evaporated totally), nitrogen partial and etc. Will oxidation mechanism/kinetic also be different? Could we make a deeper analysis on the oxide layers?