Nanjing University of Science and Technology

About: Nanjing University of Science and Technology is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 31581 authors who have published 36390 publications receiving 525474 citations. The organization is also known as: Nánjīng Lǐgōng Dàxué & Nánlǐgōng.

Characterization of a bioflocculant produced by the marine myxobacterium Nannocystis sp. NU-2.

Abstract: The marine myxobacterium strain NU-2, which can grow on high concentrations (up to 7%) of NaCl, was isolated from a salt soil sample collected from the coast of the Huanghai Sea, China. Morphological properties and 16S rDNA sequence analysis indicated that the isolate is a novel species related to the genus Nannocystis. Nannocystis sp. NU-2 produced a new kind of flocculating substance in a starch medium with a yield of 14.8 g l–1. The NU-2 flocculant was composed of 40.3% proteins and 56.5% polysaccharides, of which glucose, mannose and glucuronic acid were the principal constituents in the relative proportions of 5:4:1. The flocculation activity of the NU-2 flocculant depends strongly on cations such as Fe3+ and Al3+. When a 30 mg l–1 FeCl3 solution is present in kaolin clay suspension, 30 mg l–1of the flocculant produced a high flocculating activity value of 90%, which remained unchanged over an extensive pH range (pH 2.0–13.0). The flocculant was tested for its ability to bleach dyeing liquors, and the bleaching activities were 98.2% for acid red in 100 mg l–1of the flocculant and 99.0% for direct emerald blue in 50 mg l–1of the flocculant under test conditions. Use of the flocculant to bleach basic pink and cation emerald blue liquors was not effective.

A Compact Microstrip-Fed Patch Antenna With Enhanced Bandwidth and Harmonic Suppression

Abstract: A single-layer microstrip-fed patch antenna with capabilities of both bandwidth enhancement and harmonic suppression is proposed. For this purpose, a pair of $\lambda $ /4 microstrip-line resonators is introduced and coupled in proximity to a rectangular patch. The wideband property can be obtained by making effective use of the two resonances introduced by the radiating patch and nonradiating $\lambda $ /4 resonators. Different from other reported dual-resonance patch antennas, the proposed antenna does not require the electrically thick substrate, so it has attractive low-profile property. Thanks to the good features of $\lambda $ /4 resonators and capacitive feeding scheme, harmonic radiating modes of the patch antenna can be significantly suppressed as highly demanded in modern highly integrated communication systems. The working principle, equivalent circuit, and design procedure are extensively described. Finally, a prototype antenna operating at 4.9 GHz is designed and fabricated. The measured results show that its bandwidth is 2.7 times wider than that of the traditional insert-fed patch counterpart, and the harmful spurious radiation from other higher order radiating modes has been effectively suppressed.

Towards direct-gap silicon phases by the inverse band structure design approach.

Abstract: Diamond silicon (Si) is the leading material in the current solar cell market. However, diamond Si is an indirect band gap semiconductor with a large energy difference (2.3 eV) between the direct gap and the indirect gap, which makes it an inefficient absorber of light. In this work, we develop a novel inverse band structure design approach based on the particle swarming optimization algorithm to predict the metastable Si phases with better optical properties than diamond Si. Using our new method, we predict a cubic ${\mathrm{Si}}_{20}$ phase with quasidirect gaps of 1.55 eV, which is a promising candidate for making thin-film solar cells.