Publications by authors named "Da-Yu Li"

In high-voltage direct current transmission systems, charges accumulate at the gas-solid interface, distorting the local field strength, causing a reduction in the flashover voltage, and threatening the safe and reliable operation of the power system. The latest research has found that doping metal nanoparticles into an epoxy resin effectively suppresses the surface charge accumulation on insulators and improves their flashover voltage. This paper further analyzes the microscopic mechanism of this phenomenon, establishes a single-electron tunneling mode, and draws two conclusions: when there is no agglomeration of the doped nanoparticles, a higher doping concentration can be achieved, which provides a better insulative performance.

View Article and Find Full Text PDF

In high-voltage direct current (HVDC) transmission systems, electric charge accumulates on insulator surfaces, causing surface electric field distortion and flashover voltage reduction. Therefore, studying a material that can improve the insulator surface insulation strength is of great engineering value. In this work, several types of metal nanoparticles with different particle sizes and concentrations are doped into epoxy resin.

View Article and Find Full Text PDF

Malaria is the most common of the parasitic diseases in tropical and subtropical regions. Adverse side effects of anti-malarial drugs have precluded them as a potential clinical drug. In this study, novel derivatives of N-acetyl-L-leucyl-L-leucyl-L-norleucinal (ALLN) based on a variety of dipeptidyl α,β-unsaturated amides containing lysine as a part were synthesized and evaluated.

View Article and Find Full Text PDF

Malarial calpain is a cysteine protease believed to be a central mediator essential for parasitic activities. N-Acetyl-L-leucyl-L-leucyl-L-norleucinal (ALLN), a calpain inhibitor, showed an excellent inhibitory effect on the erythrocytic stages of Plasmodium falciparum. However the aldehyde group of ALLN makes it susceptible to metabolism.

View Article and Find Full Text PDF

Twenty five microsatellite loci were used to analyze two blue tilapia populations ["Xia'ao 1" (ZA), Guangxi population] and four nile tilapia populations [Egypt strain (ZN), 88 strain (XN), Guangxi population (GN), American strain (MN)]. A total of 7775 fragments ranging from 100 bp to 400 bp in length were obtained. Three to eight alleles were amplified in 25 loci and 143 alleles in all the six populations.

View Article and Find Full Text PDF

Ten tri- and tetranucleotide microsatellite DNA markers were isolated and characterized from common carp (Cyprinus carpio L.) to estimate genetic potential. These markers were tested in the samples from two closely related carp populations (Cyprinus carpio var.

View Article and Find Full Text PDF

Using 30 microsatellite markers and combining quantity characters such as body weight, body size and body width, we evaluated the genetic potential of 3 Germany mirror carp populations. Number of effective alleles (Ae), observed (Ho) and expected (He) heterozygosity values and polymorphic information contents (PIC) were all calculated. 287 alleles and 559 genotypes were detected.

View Article and Find Full Text PDF

In this paper, population genetic variability and genetic structure of five populations of an important cultivation species, mirror carp (Cyprinus carpio L.) were analyzed using 30 microsatellite loci. The observed (Ho) and expected (He) heterozygosity values, polymorphic information content (PIC) and number of effective alleles (Ae) were all determined.

View Article and Find Full Text PDF