The emission wavelength of an ultrafast laser generated by thulium (Tm)-doped fiber laser (TDFL) ranges from 1.7 to 2.1 μm, covering the water-absorbing band and atmospheric transmission window. In this study, an intelligent Tm-doped mode-locked fiber laser was experimentally demonstrated by combining a genetic algorithm (GA) with an adaptive mutation rate and a nonlinear polarization rotation mode-locked fiber oscillator. A closed-loop feedback system was set up in the experiment, including an oscilloscope, a laptop computer, an electric polarization controller, and a mode-locked fiber oscillator. Based on the aforementioned intelligent design of manual-operation-free, a stable femtosecond level noise-like-mode-locked pulse with an output power of 57.7 mW and a central wavelength of 1973 nm was automatically generated. The evolutionary dynamics of the different parameter structures of the GA-controlled ultrafast TDFL with varying mutation rates were also investigated. This study will pave the way for generating robust ultrafast lasers in the short-wave infrared region.

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Pashinintide A, a cyclic hexapeptide discovered from Pyrus pashia, has been synthesized in a linear sequence of 8 steps and 24% overall yield from N-Boc glycine, featuring a convergent [3 + 3] fragment coupling strategy. Although the structure of the synthetic Pashinintide A was unambiguously confirmed by X-ray diffraction analysis, its proposed complexation with sucrose cannot be validated.

Biomass-derived 5-Hydroxymethylfurfural (HMF) is a vital platform compound for synthesizing biofuel and various high-value chemicals. This work prepared carbonaceous solid catalysts with Brønsted acid and Lewis acid using pine biomass as raw materials through metal chloride impregnation, carbonization, and sulfonation. Catalysts were then applied to convert glucose into HMF in a biphasic system involving NaCl solution and gamma-valerolactone. The results showed good catalytic reactivity for carbonaceous solid catalysts. The experiment of PC-Al-SO3H catalyzed glucose obtained 85.62 mol% glucose conversion and 45.40 mol% HMF yield at 160°C and 6 h. HMF yield and glucose conversion were significantly improved compared to uncatalyzed control experiments. Further, by using PC-2Al-SO3H as the catalyst, we were able to obtain an optimum HMF yield of 59.62 mol%. Furthermore, under the same conditions, PC-2Al-SO3H showed good cycle stability, with a decrease in the yield of less than 5 mol% after 5 cycles.