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Simplified syntheses of polymaleimide employing anionic polymerization (from the melt and from solution) and metal compound-alcohol initiators such as PbO, SnO, tin bis(2-ethyl hexanoate) in the presence of tert-butyl benzyl alcohol are presented. The resulting polymers contain a combination of C-N-and C-C-connected monomers. Preliminary structures of the polymers were determined using NMR spectroscopy. The ratio of C-N-and C-C-connected monomers was determined, and the percentage of C-N-connected monomer units was found to vary from 40 to 80%, with the higher percentage resulting from anionic polymerization. The molecular weights of the polymers, as determined by gel permeation chromatography (GPC) with aqueous mobile phase and sodium polyacrylates standards, ranged between 1100 and 4200 for anionic polymerization and were about 11 500 for metal oxide-alcohol initiated polymerization. Solution-phase properties of the polymaleimides were evaluated by calcium chelation and precipitation inhibition studies. On the basis of the measured properties of these polymers, they are proposed as biodegradable, low-impact detergent additives to substitute currently used compounds.

A tungsten-rhenium thin film thermocouple is designed and fabricated, depending on the principle of thermal-electric effect caused by the high temperature. The characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. The working mechanism and thermo-electric features of the thermocouples are analyzed depending on the simulation results. Then the thin film thermocouples are fabricated and calibrated. The calibration results show that the thin film thermocouples based on the tungsten-rhenium material achieve ideal static characteristics and work well in the practical applications.

Anaerobic digestion technology mitigates agricultural organic waste pollution, thereby alleviating the energy crisis. Biochar materials increase the utilisation rate of biomass resources and promote the enrichment and growth of microorganisms. Biochar is an effective exogenous additive that stabilises the anaerobic digestion, improves anaerobic digestion efficiency and gas production. Herein, biochar materials were prepared from rice straw utilising the sequencing batch anaerobic digestion process. The biochar microstructure was characterised by scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) analysis, and microbial succession and metabolic pathways were analysed using 16S rRNA sequencing to reveal the molecular mechanisms. Rice straw biochar addition increased gas production during anaerobic fermentation. SEM revealed that numerous cocci and microbacteria became agglomerated and attached to the surface and pores of biochar, which was revealed by BET analysis to be a good habitat for microorganisms. After anaerobic digestion, the specific surface area and total pore volume of biochar decreased. 16S rRNA gene sequencing showed that biochar affected the abundance of certain bacteria and archaea. Biochar had no obvious effect on the function of bacterial flora but inhibited carbohydrate metabolism by bacteria and glycan biosynthesis and metabolism by archaea in the anaerobic fermentation system while promoting lipid metabolism by archaea. Biochar addition inhibited acetic acid production in the anaerobic fermentation system and promoted methane production based on hydrogen and carbon dioxide levels.

A thermal stress range analysis of tungsten-rhenium thin film thermocouples based on ceramic substrates is presented to analyze the falling off and breakage problems caused by the mismatch of the thermal stresses in thin film thermocouples (TFTCs) and substrate, and nano-indentation experiments are done to measure and calculate the film stress to compare with the simulation results. Optimal design and fabrication of tungsten-rhenium TFTCs based on ceramic substrates is reported. Static high temperature tests are carried out, which show the optimization design can effectively reduce the damage caused by the thermal stress mismatch.

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