Nanjing Tech University

About: Nanjing Tech University is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Membrane. The organization has 21827 authors who have published 21794 publications receiving 364050 citations. The organization is also known as: Nangongda & Nánjīng Gōngyè Dàxúe.

Accelerated carbonation – A potential approach to sequester CO2 in cement paste containing slag and reactive MgO

Abstract: The cement industry and concrete producers are under pressure to reduce the carbon footprint and energy demands of cement-based construction materials. This study investigates the CO2 uptake of paste mixtures designed with general use (GU) Portland cement, ground granulated blast furnace slag (GGBFS) and reactive MgO as cement replacement due to exposure to an accelerated carbonation curing regime with 99.9% concentration of CO2. The CO2 uptake, carbonation mechanism, microstructure and microhardness of cement pastes are examined. Key outcomes revealed that: (i) samples exposed to accelerated carbonation curing exhibit a denser microstructure and higher microhardness in comparison to non-carbonated samples, (ii) irrespective of the presence of reactive MgO, CO2 uptake increases with age from 7 to 56 d, (iii) by 56 d, pastes containing 10% and 20% reactive MgO uptake similar amounts of CO2 in comparison to mixtures without reactive MgO, and (iv) pastes containing 40% reactive MgO uptake the least amount of CO2 however, exhibit the greatest microhardness and the lowest porosity.

High-Performance Foam-Shaped Strain Sensor Based on Carbon Nanotubes and Ti3C2Tx MXene for the Monitoring of Human Activities.

Abstract: The flexible strain sensor is of significant importance in wearable electronics, since it can help monitor the physical signals from the human body. Among various strain sensors, the foam-shaped ones have received widespread attention owing to their light weight and gas permeability. However, the working range of these sensors is still not large enough, and the sensitivity needs to be further improved. In this work, we develop a high-performance foam-shaped strain sensor composed of Ti3C2Tx MXene, multiwalled carbon nanotubes (MWCNTs), and thermoplastic polyurethane (TPU). MXene sheets are adsorbed on the surface of a composite foam of MWCNTs and TPU (referred to as TPU/MWCNTs foam), which is prefabricated by using a salt-templating method. The obtained TPU/MWCNTs@MXene foam works effectively as a lightweight, easily processable, and sensitive strain sensor. The TPU/MWCNTs@MXene device can deliver a wide working strain range of ∼100% and an outstanding sensitivity as high as 363 simultaneously, superior to the state-of-the-art foam-shaped strain sensors. Moreover, the composite foam shows an excellent gas permeability and suitable elastic modulus close to those of skin, indicating its being highly comfortable as a wearable sensor. Owing to these advantages, the sensor works effectively in detecting both subtle and large human movements, such as joint motion, finger motion, and vocal cord vibration. In addition, the sensor can be used for gesture recognition, demonstrating its perspective in human-machine interaction. Because of the high sensitivity, wide working range, gas permeability, and suitable modulus, our foam-shaped composite strain sensor may have great potential in the field of flexible and wearable electronics in the near future.