Electrospinning of sulfur‐free softwood lignin (SFSL) in N,N‐dimethylformamide (DMF) is reported as is and with poly(ethylene oxide) (PEO). SFSL macromolecules behave as rigid spheres, instead of free draining macromolecules in DMF. Hence they are investigated as colloids. Colloidal SFSL generates uniform fibers only at the volume fraction of 0.63. It is due to the sufficiently high longest mean relaxation time at the volume fraction of 0.63. Colloidal SFSL below the volume fraction of 0.63 does not exhibit any measurable viscoelasticity and also does not generate any uniform fibers. Bead‐free fibers are generated at volume fractions below 0.63 only by adding PEO. PEO presence brings elasticity to colloidal SFSL and produces bead‐free fibers only above the entanglement concentration of PEO in DMF. The presence of SFSL macromolecules does not cause any interactions with PEO molecules, except it reduces the available of free volume for PEO chains in DMF.

The photochemical microreactor has been a burgeoning field with important application in promoting photocatalytic reactions. The integration of light‐converting media and microflow chemistry renders new opportunity for efficient utilization of light and high conversion rate. However, the flexibility of emission light wavelength regulation and the universality of the microreactor remain significant problems to be solved. Here, a photochemical microreactor filled with fluorescent fluid is fabricated by a 3D printing technique. The light‐converting medium in the fluorescent fluid is used to collect and convert light, and then delivers light energy to the embedded continuous‐flow reaction channels to promote the chemical reaction process. With the merits of flowability, different light‐converting media can be replaced, making it a general tool for photocatalytic reactions in rapid screening, parameters optimization, and kinetic mechanism research.

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Grape stem is a kind of agricultural and forestry waste. A fundamental understanding of grape stem pyrolysis behavior and kinetics is essential for its efficient thermochemical conversion. Thermogravimetric infrared spectroscopy and pyrolysis gas chromatography-mass spectrometry, combined with two model-free integral methods: Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) were used to investigate the weight loss behavior, the distribution and content of rapid pyrolysis products, the release law of small molecule pyrolysis gases, and the pyrolysis activation energy during pyrolysis. The results showed that the main pyrolysis reaction temperature ranged from 240 °C to 690 °C. The pyrolysis reaction of grape stems at 200 °C to 700 °C was divided into three stages: 0.15 < α < 0.35, 0.35 < α < 0.65, and 0.65 < α < 0.75, which corresponded to the main pyrolysis stages of hemicellulose, cellulose, and lignin, respectively. The products of rapid pyrolysis at 290 °C were mainly composed of acids and sugars, while the products at 355 °C were mainly phenolics. This study aims to provide a theoretical reference for the pyrolysis gasification test of grape stem.