Improved production of levoglucosan and levoglucosenone from acid-impregnated cellulose via fast pyrolysis

Cellulose - In this research, the production of levoglucosan (LG) and levoglucosenone (LGO) was improved from acid-impregnated cellulose via fast pyrolysis. Thermogravimetric and kinetic analysis...     

Hydroxyethyl cellulose-based electrically conductive,mechanically resistant,strain-sensitive self-healing hydrogels

Cellulose - Self-healing hydrogels that mimic human skin and have numerous senses of external tension and temperature are a current topic in science. However, getting skin-compatible performance...     

Triboelectric pulsed direct current for self-powered sterilization of cellulose fiber

A variety of liquid energy exists in papermaking engineering and has not yet been developed and utilized. In addition, for the papermaking industry, the presence of slime can seriously affect the quality of the finished paper and can lead to paper breaking. The current slime control strategies cannot completely solve the problem and also have some low toxicity. In this study, a method of self-powered sterilization of cellulose fibers by using triboelectric pulsed direct current is reported. A liquid–solid triboelectric nanogenerator (L–S TENG) was used to convert the liquid energy of nanocellulose suspension into electrical energy and convert this electrical energy into pulsed direct current for self-powered sterilization of cellulose fiber. A hydrophobic coating material is used as solid triboelectric material and electrode for sterilization. Driven by L–S TENG, the electrodes exhibited an excellent sterilization rate against four microorganisms including Escherichia coli, Aspergillus niger, Candida albicans, and Klebsiella pneumoniae, which from slime in the papermaking industry. This study could provide a basic research theory for liquid energy harvesting in the papermaking industry, and also provide a new strategy for pulp sterilization.

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Chemical Constituents of Corydalis saxicola

Chemistry of Natural Compounds -     

Chemical Constituents of Selaginella moellendorffii

Chemistry of Natural Compounds -     

Two New Nitrogenous Compounds from the Seeds of Brassica napus

Chemistry of Natural Compounds - Two new nitrogenous compounds identified as (2S)-2-sinapoyl-4-pentenenitrile (1) and brassicalkaloid A (2) have been isolated from the seed of Brassica napus L....     

Designing for sustainability with biocatalytic and chemoenzymatic cascade processes

Cascade reactions have been widely recognized to cut costs, decrease solvent usage, and reduce cycle times in chemical processes. Recently, biocatalytic cascades have altered how we design synthetic routes to complex molecules to achieve sustainable commercial processes for pharmaceutical, agricultural, and fine chemical industries. With advancements in protein engineering and an increase in the number of enzyme classes available to chemists, industrial and academic groups alike have endeavored to expand the scope of biocatalysis from single reactions to multi-enzyme cascades to rapidly build complex molecular structures. Recent reports have drawn inspiration from biosynthetic pathways and have applied engineered enzymes to in vitro enzymatic cascades. Furthermore, combining transition-metal catalysis and enzymes in one-pot chemoenzymatic cascades likewise serves to broaden the scope of biocatalysis, enabling traditional chemical reactions to be performed under mild aqueous conditions. In this article, we review recent biocatalytic and chemoenzymatic cascades from 2019 to 2021.     

Over 18% binary organic solar cells enabled by isomerization of non-fullerene acceptors with alkylthiophene side chains

Side-chain engineering has been demonstrated as an effective method for fine-tuning the optical, electrical, and morphological properties of organic semiconductors toward efficient organic solar cells (OSCs). In this work, three isomeric non-fullerene small molecule acceptors (SMAs), named BTP-4F-T2C8, BTP-4F-T2EH and BTP-4F-T3EH, with linear and branched alkyl chains substituted on the α or β positions of thiophene as the side chains, were synthesized and systematically investigated. The results demonstrate that the size and substitution position of alkyl side chains can greatly affect the electronic properties, molecular packing as well as crystallinity of the SMAs. After blending with donor polymer D18-Cl, the prominent device performance of 18.25% was achieved by the BTP-4F-T3EH-based solar cells, which is higher than those of the BTP-4F-T2EH-based (17.41%) and BTP-4F-T2C8-based (15.92%) ones. The enhanced performance of the BTP-4F-T3EH-based devices is attributed to its stronger crystallinity, higher electron mobility, suppressed biomolecular recombination, and the appropriate intermolecular interaction with the donor polymer. This work reveals that the side chain isomerization strategy can be a practical way in tuning the molecular packing and blend morphology for improving the performance of organic solar cells.

     

Designing a deep-UV nonlinear optical monofluorophosphate

As structural variants of famous hexagonal tungsten bronzes, hexagonal tungsten oxides(HTO) represent an important family with fascinating functional properties, such as piezoelectric, ferroelectric, pyroelectric, and nonlinear optical(NLO) properties.However, none of them are transparent in the deep-UV spectral region, which limits their applications. Herein, we report the first HTO-type monofluorophosphate K₃Sc₃(PO₄)(PO₃F)₂F₅(I)...