ELECTROCHEMILUMINESCENCE AND ELECTROCHEMISTRY FROM ZnO NANOPARTICLES IN ALKALINE AQUEOUS SOLUTION WITH PEROXYDISULFATE

LIHUA SHEN,CHENGXIAO ZHANG,BEI YAN,XIAOXIA LI 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.4

A strong electrochemiluminescence (ECL) emission from ZnO nanoparticles (NPs) suspended inaqueous solution at a Pt electrode or in NPs layers modi¯ed on a Pt or graphite electrode, whichoccurred between ? 1 : 0 V(versus Ag/AgCl, Sat. KCl) and ? 2 : 0 V, was observed in 0.25 M NaOHin the presence of peroxydisulfate. The ECL intensity was linear to the concentration of sus-pended ZnO NPs in the range from 1 : 0 ? 10? 5 to 1 : 0 ? 10? 3 g/mL. The ECL spectrum of ZnONPs revealed that both ZnO and peroxydisulfate-dissolved oxygen have been involved in the ECLprocess, and ECL spectrum has a red shift compared with photoluminescence (PL). The elec-trochemical redox behavior of ZnO NPs was also studied at a ZnO NPs modi¯ed carbon pasteelectrode by entrapping ZnO NPs in carbon paste, which reveals that the alkaline mediumchanged the surface state of ZnO NPs. The surface passivation has a signi¯cant e®ect on the ZnONPs'electrochemical behaviors.

Solar spectral management for natural photosynthesis: from photonics designs to potential applications

Shen Lihua,Yin Xiaobo 나노기술연구협의회 2022 Nano Convergence Vol.9 No.36

Photosynthesis is the most important biological process on Earth that converts solar energy to chemical energy (biomass) using sunlight as the sole energy source. The yield of photosynthesis is highly sensitive to the intensity and spectral components of light received by the photosynthetic organisms. Therefore, photon engineering has the potential to increase photosynthesis. Spectral conversion materials have been proposed for solar spectral management and widely investigated for photosynthesis by modifying the quality of light reaching the organisms since the 1990s. Such spectral conversion materials manage the photon spectrum of light by a photoconversion process, and a primary challenge faced by these materials is increasing their efficiencies. This review focuses on emerging spectral conversion materials for augmenting the photosynthesis of plants and microalgae, with a special emphasis on their fundamental design and potential applications in both greenhouse settings and microalgae cultivation systems. Finally, a discussion about the future perspectives in this field is made to overcome the remaining challenges.

The Feasibility Analysis of Recycled Aggregates from Construction and Demolition Waste for Permeable Pavement

Lihua Li,Xuanyu Shen,Jiabei Liu,Wentao Li,Chuheng Zhong,Xinlong Zhou 대한토목학회 2023 KSCE JOURNAL OF CIVIL ENGINEERING Vol.27 No.2

For reusing the construction and demolition waste (C&DW) materials and solving waterloggingproblems, the feasibility of applying C&DW to the permeable pavement (PP) was investigated. The recycled brick aggregate (RBA) and recycled concrete aggregate (RCA) were used as PPbase materials under different mixing ratios and grades. Geotextiles were also used in thisstudy as filter contaminants. Modified compaction tests, rainfall model tests, and columnleaching tests were conducted on a total of 15 samples with three gradations and five RBA andRCA mix ratios. The specimens for the rainfall model test were compacted at around optimummoisture content, and the degree of compaction was 97%. Using the sub-layer compactionmethod, each group of samples is compacted in five layers in strict accordance with thespecifications. In general, C&DW has the potential to be used underground without pollutionto the groundwater. The heavy metal concentrations in C&DW are less than in the local soiland related to material resources. The water yield performance was the best when 100%concrete was used to build PP, and the total water storage was the most when 100% of brickswere chosen to make PP. Due to the excellent permeability, C&DW can be selected forpavement fillers. The geotextile reduces the permeability by about 13% but effectively filtersout more than 50% of the fine particles in the rainfall. The permeability performance ofconcrete aggregates may be better than that of bricks, and fine particles can reduce thepermeability.

Effects of chronic alcohol exposure on ischemia–reperfusion-induced acute kidney injury in mice: the role of β-arrestin 2 and glycogen synthase kinase 3

Lihua Wang,Yifei Zhu,Lili Wang,Jingjing Hou,Yongning Gao,Lei Shen,Jingyu Zhang 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Little is known about the effects of chronic alcohol intake on the outcome of acute kidney injury (AKI). Hence, we examined the effects of chronic alcohol intake on the development of renal fibrosis following AKI in an animal model of bilateral renal ischemia–reperfusion (IR) injury. We first found that chronic alcohol exposure exacerbated bilateral IR-induced renal fibrosis and renal function impairment. This phenomenon was associated with increased bilateral IR-induced extracellular matrix deposition and an increased myofibroblast population as well as increased bilateral IR-induced expression of fibrosis-related genes in the kidneys. To explore the mechanisms underlying this phenomenon, we showed that chronic alcohol exposure enhanced β-arrestin 2 (Arrb2) expression and Akt and glycogen synthase kinase-3 (GSK3)β activation in the kidneys. Importantly, pharmacological GSK3 inhibition alleviated bilateral IR-induced renal fibrosis and renal function impairment. Furthermore, we demonstrated that Arrb2− / − mice exhibited resistance to IR-induced renal fibrosis and renal function impairment following chronic alcohol exposure, and these effects were associated with attenuated GSK3β activation in the kidneys. Taken together, our results suggest that chronic alcohol exposure may potentiate AKI via β-arrestin 2/Akt/GSK3β-mediated signaling in the kidney.

A serine/threonine phosphatase 1 of Streptococcus suis type 2 is an important virulence factor

Lihua Fang,Jingjing Zhou,Pengcheng Fan,Yunkai Yang,Hongxia Shen,Weihuan Fang 대한수의학회 2017 Journal of Veterinary Science Vol.18 No.4

Streptococcus suis is regarded as one of the major pathogens of pigs, and Streptococcus suis type 2 (SS2) is considered a zoonotic bacterium based on its ability to cause meningitis and streptococcal toxic shock-like syndrome in humans. Many bacterial species contain genes encoding serine/threonine protein phosphatases (STPs) responsible for dephosphorylation of their substrates in a single reaction step. This study investigated the role of stp1 in the pathogenesis of SS2. An isogenic stp1 mutant (stp1) was constructed from SS2 strain ZJ081101. The stp1 mutant exhibited a significant increase in adhesion to HEp-2 and bEnd.3 cells as well as increased survival in RAW264.7 cells, as compared to the parent strain. Increased survival in macrophage cells might be related to resistance to reactive oxygen species since the stp1 mutant was more resistant than its parent strain to paraquat-induced oxidative stress. However, compared to parent strain virulence, deletion of stp1 significantly attenuated virulence of SS2 in mice, as shown by the nearly double lethal dose 50 value and the lower bacterial load in organs and blood in the murine model. We conclude that Stp1 has an essential role in SS2 virulence.

DnaJ of Streptococcus suis Type 2 Contributes to Cell Adhesion and Thermotolerance

Zhang, Xiaoyan,Jiang, Xiaowu,Yang, Ling,Fang, Lihua,Shen, Hongxia,Lu, Xingmeng,Fang, Weihuan The Korean Society for Microbiology and Biotechnol 2015 Journal of microbiology and biotechnology Vol.25 No.6

To examine if the molecular chaperone DnaK operon proteins of Streptococcus suis type 2 (SS2) are involved in adhesion to host cells, the abundance values of these proteins from the surface of two SS2 strains of different adhesion capability were compared. Their roles in growth and adhesion to human laryngeal epithelial cell line HEp-2 cells were investigated on SS2 strain HA9801 and its mutants with DnaK operon genes partially knocked-out (PKO mutant) under heat stress. The major difference was that DnaJ was more abundant in strain HA9801 than in strain JX0811. Pretreatment of the bacteria with hyperimmune sera to DnaJ, but not with those to other proteins, could significantly reduce SS2 adhesion to HEp-2 cells. PKO of dnaJ g ene resulted in decreased SS2 growth at 37℃ and 42℃, and reduced its adhesion to HEp-2 cells. The wild-type strain stressed at 42℃ had increased expression of DnaJ on its surface and elevated adhesion to HEp-2 cells, which was also inhibitable by DnaJ specific antiserum. These results indicate that the DnaJ of S. suis type 2 is important not only for thermotolerance but also for adhesion to host cells. Because DnaJ expression is increased upon temperature upshift with increased exposure on the bacterial surface, the febrile conditions of the cases with systemic infections might help facilitate bacterial adhesion to host cells. DnaJ could be one of the potential candidates as a subunit vaccine because of its good immunogenicity.

pH-Responsive Multifunctional Materials with Switchable Superamphiphobicity and Superoleophobicity-Superhydrophilicity for Controllable Oil/Water Separation

Mengnan Qu,Yichen Zhou,Lili Ma,Yi Zhang,Jiaxin Wang,Shanxin Xiong,Lihua Shen,Jinmei He 한국섬유공학회 2021 Fibers and polymers Vol.22 No.3

Stimulus-responsive materials with controllable oil/water separation performance have prodigious potentialapplication. Here, a new thought for low-cost, time-saving, flexible approach has been developed to prepare a pH-responsivematerial with switchable superamphiphobicity and superoleophobicity-superhydrophilicity. The as-prepared material can beeasily applied onto multifarious substrates and presents stable superamphiphobicity. However, when the modified material istreated by alkaline solution, its surface wettability turns superhydrophilicity and superoleophobicity, thus water is allowed topenetrate through the material whereas the oil was blocked on the surface. Moreover, the surface wettability can be recoveredto superamphiphobicity quickly via treating the material with acidic aqueous. Hence, such a controllable water wettabilityand stable oil repellency property endows the as-prepared material with excellent capability to separate water from oil/watermixture. In addition, the pH-responsive materials can maintain switchable wettability after being treated by acid and alkalinumerous cycles. Furthermore, the obtained materials also exhibit excellent recyclable, self-cleaning and flame-resistantperformance, which shows potential applications for smart water-oil separators and fire-shielding protectors.