A method to determine formation position of comb teeth of Kerr micro-comb under the influence of and nonlinearity

The Kerr microcomb has a huge potential advantage as a quantum computing platform because of its large-scale and globally coherent optical modes. The micro-comb has always faced a primary problem is how to increase the controllability of frequency domain modes. In this work, based on the pump thresholds of different side modes, we establish a set of method for determining the formation position of side mode comb teeth in a micro-ring cavity with second-order ( ) and third-order ( ) nonlinearity. Based on the second-order autocorrelation function spectrum simulation, our quantum dynamical explanation has a good agreement with the experimental results.Comment: 5figures. arXiv admin note: text overlap with arXiv:2001.02356 by other author

Optimization of enzyme-producing conditions of Micrococcus sp. S-11 for L-cysteine production

Micrococcus sp.S-11 is capable of converting racemic 2-amino-Ä2-thiazoline-4-carboxylic acid (DL-ATC) to L-cysteine. The enzyme-producing conditions were optimized by using response surface methodology to maximize enzyme activity. Glucose, DL-ATC·3H2O and rotational speed have significant effects on enzyme activity. Their optimal values were 21.7 g/l glucose, 7.3 g/l DL-ATC·3H2O and 141 rpm rotational speed. Then validation experiments were conducted under optimal conditions. The enzyme activity was up to 2291 U/g, which was close to the predicted maximum enzyme activity (2284 U/g) and 31.4% higher than the initial activity (1743 U/g). A two-step culture was performed with the optimal conditions for cell growth in the first step and enzyme activity in the second step. The results suggested that high carbon/nitrogen (C/N) mass ratio was favorable to enzyme activity and the two-step culture strategy was proposed to be adopted for achieving both high biomass and enzyme production simultaneously.Key words: L-Cysteine, enzyme activity, Plackett-Burman design, response surface methodology, two-step culture

A simulated study on the performance of diesel engine with ethanol-diesel blend fuel

This paper describes the simulated study on atomization, wall-film formation, combustion and emission forming process of ethanol-diesel blend fuels in a high speed light duty diesel engine. The result shows that increased ethanol volume percentage of the blend fuels could improve atomization and reduce wall-film formation. However, in the meanwhile, with the increased ethanol volume percentage, low heat values of blend fuels decrease, while both total heat releases and cylinder pressures drop. By adding codes into the FIRE software, the NOx and soot formation region mass fractions are outputted. The simulated results display a good correlation with the NOx and soot formation. Besides, the NOx, soot and CO emissions decrease with the increased ethanol volume percentage. The power output of engine penalize, while energy utilization of blend fuels improve and combustion noise reduce, owing to the increased ethanol volume percentage

Skutterudite unicouple characterization for energy harvesting applications

Skutterudites are promising thermoelectric materials because of their high figure of merit, ZT, and good thermomechanical properties. This work reports the effective figure of merit, ZT[subscript eff], and the efficiency of skutterudite legs and a unicouple working under a large temperature difference. The p- and n-type legs are fabricated with electrodes sintered directly to the skutterudite during a hot pressing process. CoSi[subscript 2] is used as the electrode for the n-type skutterudite (Yb[subscript 0.35]Co[subscript 4]Sb[subscript 12]) and Co[subscript 2]Si for the p-type skutterudite (NdFe3.5Co0.5Sb12). A technique is developed to measure the ZTeff of individual legs and the efficiency of a unicouple. An ZT[subscript eff] of 0.74 is determined for the n-type legs operating between 52 and 595 °C, and an ZT[subscript eff] of 0.51 for the p-type legs operating between 77 and 600 °C. The efficiency of the p–n unicouple is determined to be 9.1% operating between ∼70 and 550 °C.Center for Clean Water and Clean Energy at MIT and KFUPMUnited States. Dept. of Energy. Office of Science (Award DE-SC0001299)United States. Dept. of Energy. Office of Basic Energy Sciences (Award DE-FG02-09ER46577

Study of e+e−→ppˉe^+e^- \rightarrow p\bar{p} in the vicinity of ψ(3770)\psi(3770)

Using 2917 $\rm{pb}^{-1}$ of data accumulated at 3.773~$\rm{GeV}$, 44.5~$\rm{pb}^{-1}$ of data accumulated at 3.65~$\rm{GeV}$ and data accumulated during a $\psi(3770)$ line-shape scan with the BESIII detector, the reaction $e^+e^-\rightarrow p\bar{p}$ is studied considering a possible interference between resonant and continuum amplitudes. The cross section of $e^+e^-\rightarrow\psi(3770)\rightarrow p\bar{p}$, $\sigma(e^+e^-\rightarrow\psi(3770)\rightarrow p\bar{p})$, is found to have two solutions, determined to be ($0.059\pm0.032\pm0.012$) pb with the phase angle $\phi = (255.8\pm37.9\pm4.8)^\circ$ ($<$0.11 pb at the 90% confidence level), or $\sigma(e^+e^-\rightarrow\psi(3770)\rightarrow p\bar{p}) = (2.57\pm0.12\pm0.12$) pb with $\phi = (266.9\pm6.1\pm0.9)^\circ$ both of which agree with a destructive interference. Using the obtained cross section of $\psi(3770)\rightarrow p\bar{p}$, the cross section of $p\bar{p}\rightarrow \psi(3770)$, which is useful information for the future PANDA experiment, is estimated to be either ($9.8\pm5.7$) nb ($<17.2$ nb at 90% C.L.) or $(425.6\pm42.9)$ nb