Nankai University

About: Nankai University is a education organization based out in Tianjin, China. It is known for research contribution in the topics: Catalysis & Adsorption. The organization has 42964 authors who have published 51866 publications receiving 1127896 citations. The organization is also known as: Nánkāi Dàxué.

PNIPAM microgels for biomedical applications: from dispersed particles to 3D assemblies

Abstract: Poly(N-isopropylacrylamide) (PNIPAM) microgel is perhaps the most well-known intelligent soft nanomaterial. Combining the strengths of hydrogel and nanoparticles, with unique stimuli-responsivity, PNIPAM microgels have found numerous biomedical applications, such as drug delivery, biosensing, and so on. Usually they were used as dispersed particles, however, they can also be used as building blocks to fabricate 2D films and 3D aggregates. These nanostructured assemblies exhibit new properties which the dispersed particles do not have, and new biomedical applications have been found for these assemblies. In this paper, the biomedical applications of PNIPAM microgels in the form of dispersed particles, 2D films and 3D aggregates were reviewed and some recent progress in this area was highlighted.

Massive individual orbital angular momentum channels for multiplexing enabled by Dammann gratings

Abstract: Data transmission rates in optical communication systems are approaching the limits of conventional multiplexing methods. Orbital angular momentum (OAM) in optical vortex beams offers a new degree of freedom and the potential to increase the capacity of free-space optical communication systems, with OAM beams acting as information carriers for OAM division multiplexing (OAM-DM). We demonstrate independent collinear OAM channel generation, transmission and simultaneous detection using Dammann optical vortex gratings (DOVGs). We achieve 80/160 Tbit s−1 capacity with uniform power distributions along all channels, with 1600 individually modulated quadrature phase-shift keying (QPSK)/16-QAM data channels multiplexed by 10 OAM states, 80 wavelengths and two polarizations. DOVG-enabled OAM multiplexing technology removes the bottleneck of massive OAM state parallel detection and offers an opportunity to raise optical communication systems capacity to Pbit s−1 level. Dammann gratings are used to realize multiplexing based on the generation, transmission and detection of optical angular momentum (OAM). The OAM of optical vortex beams offers a new degree of freedom for multiplexing and hence the promise of higher data communication rates, but massive parallel detection of OAM states has proved challenging. Now, researchers in China, Australia and Singapore have used Dammann optical vortex gratings (DOVGs) to realize multiplexing of massive OAM channels with individual modulation and simultaneous detection capabilities. They achieved a data capacity of 80 Tbit s−1 by multiplexing 1600 channels using ten OAM states, 80 wavelengths and two polarizations. This DOVG-enabled OAM multiplexing technology removes the bottleneck of massive parallel detection of OAM states and has the potential to increase optical communication capacities to the Pbit s−1 level.

Recent Developments on and Prospects for Electrode Materials with Hierarchical Structures for Lithium-Ion Batteries

Abstract: Since their successful commercialization in 1990s, lithium-ion batteries (LIBs) have been widely applied in portable digital products. The energy density and power density of LIBs are inadequate, however, to satisfy the continuous growth in demand. Considering the cost distribution in battery system, it is essential to explore cathode/anode materials with excellent rate capability and long cycle life. Nanometer-sized electrode materials could quickly take up and store numerous Li+ ions, afforded by short diffusion channels and large surface area. Unfortunately, low thermodynamic stability of nanoparticles results in electrochemical agglomeration and raises the risk of side reactions on electrolyte. Thus, micro/nano and hetero/hierarchical structures, characterized by ordered assembly of different sizes, phases, and/or pores, have been developed, which enable us to effectively improve the utilization, reaction kinetics, and structural stability of electrode materials. This review summarizes the recent efforts on electrode materials with hierarchical structures, and discusses the effects of hierarchical structures on electrochemical performance in detail. Multidimensional self-assembled structures can achieve integration of the advantages of materials with different sizes. Core/yolk-shell structures provide synergistic effects between the shell and the core/yolk. Porous structures with macro-, meso-, and micropores can accommodate volume expansion and facilitate electrolyte infiltration.