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The -COOH group of 12 bromododecanoic acid molecules has been observed for the last time to adopt into the same substrate. Scanning tunneling microscopic data have shown that 12-bromododecanoic acid molecules self-assemble on graphite so that the molecule adopts a 25 degree angle between the direction of the hydrogen bond and the hydrocarbon backbone. 2-bromoheadecanoic acid molecules orient with a 53 degree angle between the hydrogen bond direction and the long molecular axis when physisorbed on the same graphite substrate.

A study was conducted to analyze the effects of different substrates on monolayer ordering and molecular image contrast associated with singly and doubly substituted long-chain hydrocarbons using scanning tunneling microscopy (STM). Results indicated an interplay between geometric/topological and electronic coupling factors in the STM tunneling mechanism. Findings also showed that most of the molecules supported self-assembly in two dimensions to generate similar patterns in topographs.

Scanning tunneling microscopic studies were performed to study thin film and interfacial ordering in doubly substituted 11-bromoundecanoic acid, Br(CH2)10COOH, and 12-bromododecanoic acid, Br(CH2)11COOH. In particular, the influence of chain length on the carbon atom arrangements were analyzed. Samples of the acids adsorbed at the phenyloctane solution-graphite interface were examined. Both molecules display structures different from their monosubstituted correlates. Moreover, the number of odd or even hydrocarbon chains affected the packing structure of the molecules.

Experiments were performed to investigate the chiral molecules (R)/(S)-2-bromohexadecanoic acid adsorbed on a graphite surface. The chirality of the molecules were measured in a liquid/solid interface using scanning tunneling microscopic (STM) analyses. The separation of the enantiomers at the graphite surface was observed. Mirror image packing patterns on the graphite surface were demonstrated. The study confirmed the usefulness of STM in determining the chirality of organic molecules.

The self-assembly of a mixture of hexadecanoic acid with (R)-2-Br-hexadecanois acid and (S)-2-Br-hexadecanois acid at the liquid-solid interface is investigated using scanning tunneling microscopy (STM). The absolute conformation of the bromine atom in 2-Br-hexadecanoic acids is determined to be pointing up away from the graphite surface.

The evaluation of toxicity and environmental behavior of bioactive lead molecules is helpful in providing theoretical support for the development of agrochemicals, in line with the sustainable development of the ecological environment. In previous work, some acethydrazide structures have been demonstrated to exhibit excellent and broad-spectrum fungicidal activity; however, its environmental compatibility needs to be further elucidated if it is to be identified as a potential fungicide. In this project, the toxicity of fungicidal acethydrazide lead compounds F51, F58, F72, and F75 to zebrafish was determined at 10 μg mL -1 and 1 μg mL -1 . Subsequently, the toxic mechanism of compound F58 was preliminarily explored by histologic section and TEM observations, which revealed that the gallbladder volume of common carp treated with compound F58 increased, accompanied by a deepened bile color, damaged plasma membrane, and atrophied mitochondria in gallbladder cells. Approximately, F58-treated hepatocytes exhibited cytoplasmic heterogeneity, with partial cellular vacuolation and mitochondrial membrane rupture. Metabolomics analysis further indicated that differential metabolites were enriched in the bile formation-associated steroid biosynthesis, primary bile acid biosynthesis, and taurine and hypotaurine metabolism pathways, as well as in the membrane function-related glycerophospholipid metabolism, linolenic acid metabolism, α-linolenic acid metabolism, and arachidonic acid metabolism pathways, suggesting that the acethydrazide F58 may have acute liver toxicity to common carp. Finally, the hydrolysis dynamics of F58 was investigated, with the obtained half-life of 5.82 days. The above results provide important guiding significance for the development of new green fungicides.