Chemical Modifications of Chitin and Chitosan

Abstract Negative resistance drift in thick film chip resistors in high temperature and high humidity application conditions was investigated. This paper reports on the investigation of possible causes including formation of current leakage paths on the printed circuit board, delamination between the resistor protective coating and laser trim, and the possibility of silver migration or copper dendrite formation. Analysis was performed on a set of circuit boards exhibiting failures due to this phenomenon. Electrical tests after mechanical and chemical modifications showed that the drift was most likely caused by moisture ingress that created a conductive path across the laser trim.

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Recognition Pattern, Functional Mechanism and Application of Chitin and Chitosan Oligosaccharides in Sustainable Agriculture

Current Pharmaceutical Design ◽

10.2174/1381612826666200617165915 ◽

2020 ◽

Vol 26 (29) ◽

pp. 3508-3521 ◽

Cited By ~ 1

Author(s):

Xiaochen Jia ◽

Mijanur R. Rajib ◽

Heng Yin

Keyword(s):

Agricultural Production ◽

Growth And Yield ◽

Biotic Stresses ◽

The Past ◽

Chitosan Oligosaccharides ◽

Recognition Pattern ◽

Functional Mechanism ◽

Chitin And Chitosan ◽

And Storage ◽

Further Development

Background: Application of chitin attracts much attention in the past decades as the second abundant polysaccharides in the world after cellulose. Chitin oligosaccharides (CTOS) and its deacetylated derivative chitosan oligosaccharides (COS) were shown great potentiality in agriculture by enhancing plant resistance to abiotic or biotic stresses, promoting plant growth and yield, improving fruits quality and storage, etc. Those applications have already served huge economic and social benefits for many years. However, the recognition mode and functional mechanism of CTOS and COS on plants have gradually revealed just in recent years. Objective: Recognition pattern and functional mechanism of CTOS and COS in plant together with application status of COS in agricultural production will be well described in this review. By which we wish to promote further development and application of CTOS and COS–related products in the field.

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Rational Generation of Lasso Peptides Based on Biosynthetic Gene Mutations and Site-Selective Chemical Modifications

Chemical Science ◽

10.1039/d1sc02695j ◽

2021 ◽

Author(s):

Tan Liu ◽

Xiaojie Ma ◽

Jiahui Yu ◽

Wensheng Yang ◽

guiyang wang ◽

...

Keyword(s):

Natural Products ◽

Gene Mutations ◽

Proteolytic Degradation ◽

Biosynthetic Gene ◽

Chemical Modifications ◽

Lasso Peptides ◽

Selective Chemical ◽

Site Selective

Lasso peptides are a unique family of natural products whose structures feature a specific threaded fold, which confers these peptides the resistance to thermal and proteolytic degradation. This stability gives...

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