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Abstract??Nocardiasp. 108 exhibited strong acrylonitrile-hydrating activity and its nitrile hydratase was Co2+-dependent.Nocardiasp. 108 was active within a broad pH range from 6.0 to 10.0 at 30?C and thermostable at temperatures below 35?C, but became unstable at temperatures above 45?C. Furthermore, it was found thatNocardiasp. 108 can hydrate indole-3-acetonitrile,p-chlorobenzonitrile,p-hydroxybenzylcyanide, 3,4,5-trimethoxybenzonitrile,p-aminobenzonitrile, 3-cyanopyridine,o-chlorobenzonitrile to the corresponding amides and hence displayed a broad substrate specificity. The temperature and pH optima for these hydrations were 28?C and pH 7.0?7.5, respectively. At the observed concentrations, acrylonitrile was completely converted within 5?min, while 3,4,5-trimethoxybenzonitrile,p-aminobenzonitrile, indole-3-acetonitrile,p-chlorobenzonitrile were approximately 21.71, 8.98, 34.44, 93.10% hydrated.p-Chlorobenzonitrile appeared to be the preferred aromatic nitrile forNocardiasp. 108. [ABSTRACT FROM AUTHOR]

A dumbbell-shaped fiber laser with dual-functional pulsed outputs is demonstrated using a filmy polyvinyl alcohol-based gold nanorods (GNRs) saturable absorber (SA), which can deliver mode-locked soliton and multiwavelength Q-switched pulse. The GNRs-SA is fabricated by seed-mediated method with a modulation depth of 4.1% and nonsaturable loss of 32.9%. When the fiber laser operates in mode-locked regime, stable fundamental solitons with a temporal width of 910 fs and repetition rate of 2.88 MHz are directly generated from the laser cavity. The corresponding spectrum is located at 1560.1 nm with a 3-dB bandwidth of 3.08 nm. When the laser operates in Q-switched regime, more than 5-wavelength oscillation is achieved. The repetition rate of Q-switched monotonically increases from 13.4 to 31.7 kHz and the pulse duration can be significantly narrowed from 6.07 to 3.12 μs by varying the pump power from 128 to 154 mW. The results further expand the applications of GNRs-SA to obtain versatile pulse sources in ultrafast laser field. [ABSTRACT FROM AUTHOR]