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  1. UK consultancy focuses on AM and composites

    A new supply chain management consultancy has been launched in the UK focusing on SMEs in the automotive, aerospace and defense sectors.

    According to Develop and Supply In-Sync (DASIS), the company covers aspects of the product manufacturing process from concept to completion for sectors such as CNC machining, composites, additive manufacturing (AM), technical products, engineering services and consumable products.

    ‘Together with our consortium of trusted partners, we offer businesses a unified and bespoke service that ensures on time delivery of first-class products and components,’ said Ian Wilson, CEO of DASIS. ‘Our extensive knowledge of program management, combined with hands on manufacturing experience, has allowed us to fulfil a dream of synchronising supply chain activity.’

    This story uses material from DASIS, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.

  2. PM in orbit seminar
    The EPMA's webinar is about how to produce metal powder at low orbit with low or reduced gravity.
    The EPMA's webinar is about how to produce metal powder at low orbit with low or reduced gravity.

    The EPMA is hosting a webinar covering the possibility of producing metal powder at low orbit with low or reduced gravity.

    ‘With the increased activity of space agencies and even private companies in space, there is a growing number of examples of successful research carried out in microgravity conditions in order to improve industrial processes at ground level,’ the organisation said. ‘In the past, powder metallurgy experiments have been carried out, for instance, on board of the International Space Station.’

    The webinar will feature a presentation from US company Space Commerce Matters (SCM) about conducting technology experiments in low orbit flights.

    The deadline for registration is 25 January 2021. To register, go here and for more information go here.

    This story uses material from the EPMA, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.

  3. Nanodroplets sound like a great way to break up blood clots
    The new technique uses an ultrasound 'drill' to burst nanodroplets in and around hardened blood clots. As the nanodroplets burst into microbubbles, the ultrasound causes the microbubbles to oscillate  disrupting the clot's physical structure. Image: Leela Goel.
    The new technique uses an ultrasound 'drill' to burst nanodroplets in and around hardened blood clots. As the nanodroplets burst into microbubbles, the ultrasound causes the microbubbles to oscillate disrupting the clot's physical structure. Image: Leela Goel.

    Engineering researchers have developed a new technique for eliminating particularly tough blood clots, by using engineered nanodroplets and an ultrasound 'drill' to break up the clots from the inside out. The technique has not yet gone through clinical testing, but in vitro testing has shown promising results.

    Specifically, the new approach is designed to treat retracted blood clots, which form over extended periods of time and are especially dense. These clots are particularly difficult to treat because they are less porous than other clots, making it hard for drugs that dissolve blood clots to penetrate into the clot.

    The new technique has two key components: the nanodroplets and the ultrasound drill. The nanodroplets consist of tiny lipid spheres that are filled with liquid perfluorocarbons (PFCs). Specifically, the nanodroplets are filled with low-boiling-point PFCs, which means that a small amount of ultrasound energy will cause the liquid to convert into gas. As they convert into a gas, the PFCs expand rapidly, vaporizing the nanodroplets and forming microscopic bubbles.

    "We introduce nanodroplets to the site of the clot, and because the nanodroplets are so small, they are able to penetrate and convert to microbubbles within the clots when they are exposed to ultrasound," explains Leela Goel, first author of a paper on this work in Microsystems & Nanoengineering. Goel is a PhD student in the joint biomedical engineering department at North Carolina (NC) State University and the University of North Carolina (UNC) at Chapel Hill.

    After the microbubbles form within the clots, the continued exposure of the clots to ultrasound oscillates the microbubbles. This rapid vibration causes the microbubbles to behave like tiny jackhammers, disrupting the physical structure of the clots and helping to dissolve them. This vibration also creates larger holes in the clot mass that allow blood-borne anti-clotting drugs to penetrate deep into the clot and further break it down.

    The technique is made possible by the ultrasound drill – which is an ultrasound transducer that is small enough to be introduced to the blood vessel via a catheter. The drill can aim ultrasound directly ahead, which makes it extremely precise. It is also able to direct enough ultrasound energy to the targeted location to activate the nanodroplets, without causing damage to surrounding healthy tissue. The drill incorporates a tube that allows users to inject nanodroplets at the site of the clot.

    In in vitro testing, the researchers compared the new technique with various combinations of drug treatment, microbubbles and ultrasound for eliminating blood clots.

    "We found that the use of nanodroplets, ultrasound and drug treatment was the most effective, decreasing the size of the clot by 40%, plus or minus 9%," says Xiaoning Jiang, professor of mechanical and aerospace engineering at NC State and corresponding author of the paper. "Using the nanodroplets and ultrasound alone reduced the mass by 30%, plus or minus 8%. The next best treatment involved drug treatment, microbubbles and ultrasound – and that reduced clot mass by only 17%, plus or minus 9%. All these tests were conducted with the same 30-minute treatment period.

    "These early test results are very promising."

    "The use of ultrasound to disrupt blood clots has been studied for years, including several substantial studies in patients in Europe, with limited success," says co-author Paul Dayton, professor of biomedical engineering at UNC and NC State. "However, the addition of the low-boiling-point nanodroplets, combined with the ultrasound drill, has demonstrated a substantial advance in this technology."

    "Next steps will involve pre-clinical testing in animal models that will help us assess how safe and effective this technique may be for treating deep vein thrombosis," says Zhen Xu, a professor of biomedical engineering at the University of Michigan and co-author of the paper.

    This story is adapted from material from North Carolina State University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.

  4. Antioxidants can protect health of conducting polymers
    Adding antioxidants can push the resolution limit of polymer electron microscopy to reveal structures at smaller scales (blue) than could previously be observed (pink) in this false-color image. Image: Brooke Kuei, Penn State.
    Adding antioxidants can push the resolution limit of polymer electron microscopy to reveal structures at smaller scales (blue) than could previously be observed (pink) in this false-color image. Image: Brooke Kuei, Penn State.

    Reactive molecules such as free radicals can be produced in the body after exposure to certain environments or substances and go on to cause cell damage. Antioxidants can minimize this damage by interacting with the radicals before they affect cells.

    A team of researchers has now applied this concept to the task of preventing imaging damage to the conducting polymers found in soft electronic devices such as organic solar cells, organic transistors, bioelectronic devices and flexible electronics. The researchers, led by Enrique Gomez, professor of chemical engineering and materials science and engineering at Penn State, report their findings in a paper in Nature Communications.

    According to Gomez, visualizing the structures of conducting polymers is crucial to the further development of these materials and their commercialization in soft electronic devices – but the imaging process can cause damage to the polymers that limits what researchers can see and understand.

    "It turns out antioxidants, like those you'd find in berries, aren't just good for you but are also good for polymer microscopy," Gomez said.

    Polymers can only be imaged to a certain point with high-resolution transmission electron microscopy (HRTEM), because the bombardment of electrons used to form images breaks the sample apart. The researchers examined this damage with the goal of identifying its fundamental cause.

    They found that the HRTEM electron beam generates free radicals that degrade the sample's molecular structure. But introducing butylated hydroxytoluene, an antioxidant often used as a food additive, to the polymer sample prevented this damage and removed another restriction on imaging conditions – temperature.

    "Until now, the main strategy for minimizing polymer damage has been imaging at very low temperatures," said paper co-author Brooke Kuei, who recently earned her doctorate in materials science and engineering in the Penn State College of Earth and Mineral Sciences. "Our work demonstrates that the beam damage can be minimized with the addition of antioxidants at room temperature."

    Although the researchers did not quantitatively test the resolution limits that resulted from this method, they were able to image the polymer at a resolution of 3.6 angstroms, an improvement on their previous resolution of 16 angstroms.

    Polymers are made up of molecular chains lying on top of each other. The previous resolution of 16 angstroms was the distance between chains, but imaging at 3.6 angstroms allowed the researchers to visualize patterns of close contacts along the chains. For the electrically conductive polymer examined in this study, this meant the researchers could follow the direction along which electrons travel. According to Gomez, this allows them to better understand the conductive structures in the polymers.

    "The key to this advancement in polymer microscopy was understanding the fundamentals of how the damage occurs in these polymers," Gomez said. "This technological advance will hopefully help lead to the next generation of organic polymers."

    This story is adapted from material from Penn State, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.

  5. Single stage process for converting coal into graphite
    This method provides a new route to convert abundant carbon sources to high-value materials with ecological and economic benefitsTe-Yu Chien

    Researchers at the University of Wyoming have shown how to easily and cheaply convert coal powder into graphite using just copper foil, glass containers and a standard microwave oven. With the demand for coal declining due to climate change, this breakthrough in pulverizing coal powder into nano-graphite – which is used as a lubricant and in a range of products such as lithium-ion batteries and fire extinguishers – could help identify new uses for coal.

    Although previous studies had used microwaves to reduce the moisture content of coal, as well as remove sulfur and other minerals, these approaches tend to depend on chemical pre-treatment of the coal and are problematic due to the complexity and interpretation of the results. However, as reported in the journal Nano-Structures & Nano-Objects [Masi et al. Nano-Struct. Nano-Objects (2020) DOI: 10.1016/j.nanoso.2020.100660], here raw coal powder was converted into nano-graphite in a single stage approach based around four factors: high temperature, a reducing environment, a catalyst and microwave radiation.

    Raw coal was first ground into powder, before it was positioned on copper foil and sealed in a glass vial with a gas mixture of argon and hydrogen, and then put into a conventional household microwave oven. Sparks produced by the microwaves made the high temperatures required to change the coal powder into polycrystalline graphite, a process that was also facilitated by the copper foil and hydrogen gas. On testing microwave durations of up to 45 minutes, it was found that the best duration was 15 minutes.

    With finite graphite reserves and environmental concerns about how it is extracted, this new approach to coal conversion could be refined to offer a higher quality and quantity of nano-graphite materials. As team leader TeYu Chien said, “This method provides a new route to convert abundant carbon sources to high-value materials with ecological and economic benefits”.

    Further research is needed to assess if their approach is viable at a larger scale, and if it is possible to extract or isolate the converted graphite from the non-converted matrix. However, modifying the recipe could lead to new possibilities of treating coal and other materials of interest, and the team have already tried using plastic powder from a conventional plastic water bottle. Various functional and complex materials could also be produced by changing the metal used, or the temperature, or varying the source materials to target different areas, while modifying the environment could provide different reactions such as doping.

    Sparks produced by a microwave oven help change coal powder into graphite
    Sparks produced by a microwave oven help change coal powder into graphite

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