Harbin Engineering University

About: Harbin Engineering University is a education organization based out in Harbin, Heilongjiang, China. It is known for research contribution in the topics: Control theory & Computer science. The organization has 31149 authors who have published 27940 publications receiving 276787 citations. The organization is also known as: HEU.

Synthesis and H2S gas sensing properties of cage-like α-MoO3/ZnO composite

Abstract: α-MoO 3 /ZnO composite with a novel cage-like morphology, composed of nanosheets with a thickness of about 25 nm, was synthesized via a hydrothermal method. The cage-like composite was of porous characteristics with a pore size distribution from 4 to 174 nm. The Brunauer–Emmett–Teller (BET) surface area of the cage-like composite was 58.22 m 2 /g, which was great higher than that of α-MoO 3 nanorods (8.94 m 2 /g). The special structural characteristic of the composite resulted in its excellent H 2 S sensing properties including very high sensor response, low working temperature and good selectivity.

Upconversion processes: versatile biological applications and biosafety

Abstract: Lanthanide-doped photon upconverting nanomaterials are evolving as a new class of imaging contrast agents, offering highly promising prospects in the area of biomedical applications Owing to their ability to convert long-wavelength near-infrared excitation radiation into shorter-wavelength emissions, these nanomaterials are well suited to yield properties of low imaging background, large anti-Stokes shift, along with high optical penetration depth of NIR light for deep tissue optical imaging or light-activated drug release and therapy Such materials have potential for significant advantages in analytical applications compared to molecular fluorophores and quantum dots The use of IR radiation as an excitation source diminishes autofluorescence and scattering of excitation radiation, which leads to a reduction of background in optical experiments The upconverting nanocrystals show exceptional photostability and are constituted of materials that are not significantly toxic to biological organisms Excitation at long wavelengths also minimizes damage to biological materials In this detailed review, various mechanisms operating for the upconversion process, and methods that are utilized to synthesize and decorate upconverting nanoparticles are investigated to elucidate by what means absorption and emission can be tuned Up-to-date reports concerning cellular internalization, biodistribution, excretion, cytotoxicity and in vivo toxic effects of UCNPs are discussed Specifically, studies which assessed the relationship between the chemical and physical properties of UCNPs and their biodistribution, excretion, and toxic effects are reviewed in detail Finally, we also deliberate the challenges of guaranteeing the biosafety of UCNPs in vivo

Twin-core fiber optical tweezers

Abstract: We present an abruptly tapered twin-core fiber optical tweezers, which is fabricated by fusing and drawing the twin-core fiber. In the twin-core fiber, the two beams are guided by the tapered fiber. At the end of the fiber tip, a larger converge angle between the two beams are made due to the abrupt tapered shape, which is formed a fast divergent optical field. The microscopic particle trapping performance of this special designed tapered twin-core fiber tip is investigated. The functionality of the proposed novel twin-core fiber optical tweezers is extended since an in-fiber integrated Mach-Zehnder interferometer has been used to control orientation of the trapped particle. The distribution of the optical field emerging from the tapered fiber tip is simulated based on the beam propagation method (BPM). By using this two-beam combination technique, a strong enough gradient forces well is obtained for microscopic particles trapping in three dimensions. The abruptly tapered twin-core fiber optical tweezers is rigid and easy to handle, especially useful for building up a multi-tweezers system for trapping and manipulating micro-scale particles.