How can biopolymers be modified for the synthesis of new biopolymer aerogels?5 answersBiopolymers can be modified for the synthesis of new biopolymer aerogels by compositing them with a polysiloxane network, which overcomes the drawbacks of hydrophilicity and difficulty in achieving homogeneous structures in nanoscale. Another approach is the deposition of protective hydrophobic and oleophobic polymer layers on hydrophilic biopolymer aerogels using cold plasma polymerization. The synthesis protocol of chitosan aerogels can be controlled to achieve desired microstructures by manipulating solvent-polymer and polymer-drying interactions. Computational approaches combining random closed packing of polydisperse spheres and Laguerre-Voronoi tessellation can be used to reconstruct or design the three-dimensional microstructure of nanoporous materials, such as κ-carrageenan aerogels. Urea-modified chitosan aerogels can be synthesized by triggering the irreversible gelation of an acidic chitosan solution through the thermal decomposition of urea, followed by drying using supercritical CO2 drying or ambient pressure drying methods.
What is the chemical composition of corn stover?3 answersCorn stover is mainly composed of three parts: pith (CSP), rind (CSR), and leaf (CSL). The lignocellulosic compositions of CSP and CSR are similar, with higher cellulose content and lower lignin content compared to CSL. CSP has the highest oil adsorption capacity, CSR is more suitable for adsorbing antibiotics, and CSL has outstanding adsorption capacity for dyes. Pretreated corn stover exhibits higher cellulose content and less lignin compared to untreated biomass. Maize stover fractions have different chemical and structural parameters, with stalks having the highest cellulose and lignin contents, as well as the highest crystallinity index. Enzyme sequence action affects the chemical composition of corn stover, with the best sequence being Hem-Cel-Pec-Lac for improving degradation. Biological treatment with Trametes versicolor can achieve lignin degradation in corn stover, with a 43.37% conversion after 30 days.
How does corn stover affect soil carbon?5 answersCorn stover removal can negatively impact soil carbon stocks, leading to a decrease in soil organic carbon levels over time. Stover removal resulted in a decrease in soil organic carbon content after 6 years of consecutive treatment. In contrast, stover incorporation after corn harvest was found to enhance soil carbon pools and maintain soil organic carbon levels. Stover retention increased average soil organic carbon stocks over time, with a sequestration rate of 0.41 Mg C ha-1 year-1. Additionally, the incorporation of stover into soil stimulated microbial communities, leading to an increase in soil quality. Overall, the management of corn stover, whether through removal or incorporation, has significant implications for soil carbon dynamics and should be carefully considered to maintain soil health and fertility.
How can corn bran be converted into biofuel?5 answersCorn bran can be converted into biofuel through various methods. One method involves fermenting the corn bran fibers using Aspergillus niger HYA4 solids to prepare a bacterial degumming solution, followed by degumming the fibers. Another method involves pretreating the corn bran and hydrolyzing it to obtain sugar, which can then be used for microbial lipid production using oleaginous yeast. Additionally, corn bran can be used as a component in the preparation of biofuel along with other renewable materials such as sawdust, bamboo chips, and carbonized corn stalk powder. These methods offer energy-saving and environmentally-friendly ways to utilize corn bran for biofuel production.
How much does graphene Aerogel cost?10 answers
Who invented graphene Aerogel?10 answers