An adequate avenue towards well-designed PBDT-DTNT:PCBM active layers via quantum dot/conductive polymer configurations

Chenxi Liu,Samira Agbolaghi 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.99 No.-

Graphene quantum dots (GQD) and carbon quantum dots (CQD) were employed to develop the patternedGQD/CQD/poly[benzodithiophene-bis(decyltetradecyl-thien) naphthothiadiazole] (PBDT-DTNT) short/long chain, crab-like GQD/semicrab-like CQD/poly(3-hexylthiophene) (P3HT) short chain, and pellet-likeGQD/CQD/P3HT long chain supramolecules. Nanostructures were used in roles of modifier, donor, andacceptor constituents in ternary (PBDT-DTNT:[6,6]-phenyl-C71 butyric acid methyl ester (PC71BM)) andbinary photoactive layers. Application of pre-designed patterned quantum dot (QD)/PBDT-DTNT shortchain nano-hybrids as morphology modifier promoted the performance up to 4.79%. P3HT-basedsupramolecules acted conspicuously better than PBDT-DTNT ones. The highest efficacies of 7.14 and 6.24%were detected in PBDT-DTNT:PC71BM:GQD/P3HT short chain (14.63 mA cm–2, 68.71%, 0.71 V and287 V cm2) and PBDT-DTNT:PC71BM:CQD/P3HT short chain (13.35 mA cm–2, 66.79%, 0.70 V and447 V cm2) systems, respectively. In addition to ternary photovoltaics, the binary devices werefabricated using the QDs and their associated supramolecules as donor and acceptor agents. Exactlysimilar to ternary cells, the crab/semicrab-like and pellet-like nano-hybrids, acted better than the PBDTDTNTpatterned nano-hybrids. The best results were recorded for PBDT-DTNT:GQD/P3HT short chain(2.93%) and PBDT-DTNT:CQD/P3HT short chain (2.67%) solar cells. In second type of binary photovoltaics,the QDs and their correlated supramolecules were utilized as electron donor and a maximumperformance of 0.22% was acquired.

Combination of berberine and ciprofloxacin reduces multi-resistant Salmonella strain biofilm formation by depressing mRNA expressions of luxS, rpoE, and ompR

Chenxi Shi,Minmin Li,Ishfaq Muhammad,Xin Ma,Yicong Chang,Rui Li,Changwen Li,Jingshan He,Fangping Liu 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.6

Bacterial biofilms have been demonstrated to be closely related to clinical infections and contribute to drug resistance. Berberine, which is the main component of Coptis chinensis, has been reported to have efficient antibacterial activity. This study aimed to investigate the potential effect of a combination of berberine with ciprofloxacin (CIP) to inhibit Salmonella biofilm formation and its effect on expressions of related genes (rpoE, luxS, and ompR). The fractional inhibitory concentration (FIC) index of the combination of berberine with CIP is 0.75 showing a synergistic antibacterial effect. The biofilm’s adhesion rate and growth curve showed that the multi-resistant Salmonella strain had the potential to form a biofilm relative to that of strain CVCC528, and the antibiofilm effects were in a dose-dependent manner. Biofilm microstructures were rarely observed at 1/2 × MIC/FIC concentrations (MIC, minimal inhibition concentration), and the combination had a stronger antibiofilm effect than each of the antimicrobial agents used alone at 1/4 × FIC concentration. LuxS, rpoE, and ompR mRNA expressions were significantly repressed (p < 0.01) at 1/2 × MIC/FIC concentrations, and the berberine and CIP combination repressed mRNA expressions more strongly at the 1/4 × FIC concentration. The results indicate that the combination of berberine and CIP has a synergistic effect and is effective in inhibiting Salmonella biofilm formation via repression of luxS, rpoE, and ompR mRNA expressions.

Effect of passivator DHJ-C on the growth and cadmium accumulation of Brassica napus in Cd-contaminated soil

Wang Xin,Liu Qian,Wan Yunbao,Cao Chenxi,Bai Jiuyuan,Wang Rui,Zhao Yun 한국응용생명화학회 2021 Applied Biological Chemistry (Appl Biol Chem) Vol.64 No.2

The farmland polluted by cadmium is increasing drastically, which seriously threatened agricultural production and food safety. Nowadays, efficient and convenient way to solve the problem is urgently needed. In this experiment, a particular compound passivator DHJ-C was applied for soil remediation by pot experiment and the effect on both soil and plant was evaluated. The DHJ-C reduced the toxicity of Cd on soil enzyme activity and growth inhibition on Brassica napus. The soil urease and sucrase activity were significantly increased. The dry weight of mature oilseed rape increased by 14.6–36.0% and the yield of seeds increased by 14.1–52% per plant, which suggested that the passivator effectively reduced the detrimental effects on rape. Similarly, the results of physiology and biochemistry also indicated that DHJ-C can distinctly alleviate the inhibitory effect of Cd on plant growth. Such as the MDA content in plant was reduced by 52.1% in 10 mg/kg Cd treatment. Compared with control, Cd accumulation in seedling stage and mature period was significantly reduced as the concentration of Cd in aboveground part even decreased by 18.4 and 32.0% respectively. Overall, DHJ-C hold sufficient ability to be applied as an excellent passivator to reduce Cd toxicity in contaminated soil and significantly increase the yield of rapeseed.

Impact of Elevated Base Stations on the Ultra-Dense Networks

Cho, Hewon,Liu, Chenxi,Lee, Jemin,Noh, Taegyun,Quek, Tony Q. S. IEEE 2018 IEEE communications letters Vol.22 No.6

<P>In this letter, we examine the impact of the elevated base stations (BSs) on the performance of ultra-dense networks (UDNs). To this end, we first model the channel between an elevated BS and typical user equipment as a 3-D probabilistic line-of-sight channel by considering the height of BSs. Using stochastic geometry, we then derive the expression for the coverage probability of our considered UDNs. Finally, through numerical results, we show how the coverage probability can be maximized by judiciously selecting the height and the density of BSs. The results reported here provide insights into the deployment of BSs in the UDNs.</P>

Shaking Table Test of Water Supply Pipes Installed in a Full-Scale Masonry Structure

Houli Wu,Endong Guo,Dezhang Sun,Chenxi Mao,Haoyu Zhang,Zhibin Liu 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.2

The seismic performance of indoor water supply pipes plays a significant role during earthquakes, and the failure of pipes causes severe economic losses and other disasters. This paper presents shaking table test research on water supply pipes installed in a full-scale masonry structure. Three different material pipes and three different material fillers were combined to evaluate the difference in seismic performance. In this study, normalized floor response spectra and pipe acceleration amplification factors obtained from experimental data were compared with code provisions. Spectrum analysis was used to evaluate the pipeline seismic response, and the results showed that the combination of pipes and fillers with similar material properties vibrated partially at multiple frequencies. In contrast, the combination of pipes and fillers with very different material properties only vibrated near the predominant structural period.

Contact toxicity of a new acaricide, SYP-9625, to the natural predator, Chrysopa pallens

Feng Yanjiao,Zhang Lisheng,Chen Hongyin,Wang Mengqing,Liu Chenxi,Li Yuyan,Song Yuquan,Mao Jianjun 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.2

SYP-9625 is a novel acaricide synthesized by using cyenopyrafen as lead compound. It is characterized by high acaricidal activity and low toxicity to mammals and has been widely used in Chinese farming areas. However, to date, the toxicity of SYP-9625 to natural enemy insects remained unclear. Here, we evaluated the effects of SYP-9625 on survival, growth, metamorphosis and reproduction of a common natural predator, Chrysopa pallens. Contact toxicity bioassay revealed that SYP-9625 had no significant detrimental impacts on egg hatchability, larval survival and duration, pupation rate, pupal mass, emergence rate, digestive enzyme activity, reproductive output and offspring quality, but drastically reduced adult survival rate, adult lifespan, secondary follicle size and vitellogenin (Vg) transcripts by 27.8%, 15.4%, 33.4% and 59.4%, respectively, suggesting a low contact toxicity of SYP-9625 to C. pallens. This study will strengthen the compatibility of chemical acaricide and natural enemy insects in integrated pest management.

Band Structure Engineering of Layered WSe₂<i>via</i> One-Step Chemical Functionalization

Park, Jun Hong,Rai, Amritesh,Hwang, Jeongwoon,Zhang, Chenxi,Kwak, Iljo,Wolf, Steven F.,Vishwanath, Suresh,Liu, Xinyu,Dobrowolska, Malgorzata,Furdyna, Jacek,Xing, Huili Grace,Cho, Kyeongjae,Banerjee, S American Chemical Society 2019 ACS NANO Vol.13 No.7

<P>Chemical functionalization is demonstrated to enhance the p-type electrical performance of two-dimensional (2D) layered tungsten diselenide (WSe<SUB>2</SUB>) field-effect transistors (FETs) using a one-step dipping process in an aqueous solution of ammonium sulfide [(NH<SUB>4</SUB>)<SUB>2</SUB>S(aq)]. Molecularly resolved scanning tunneling microscopy and spectroscopy reveal that molecular adsorption on a monolayer WSe<SUB>2</SUB> surface induces a reduction of the electronic band gap from 2.1 to 1.1 eV and a Fermi level shift toward the WSe<SUB>2</SUB> valence band edge (VBE), consistent with an increase in the density of positive charge carriers. The mechanism of electronic transformation of WSe<SUB>2</SUB> by (NH<SUB>4</SUB>)<SUB>2</SUB>S(aq) chemical treatment is elucidated using density functional theory calculations which reveal that molecular “SH” adsorption on the WSe<SUB>2</SUB> surface introduces additional in-gap states near the VBE, thereby, inducing a Fermi level shift toward the VBE along with a reduction in the electronic band gap. As a result of the (NH<SUB>4</SUB>)<SUB>2</SUB>S(aq) chemical treatment, the p-branch ON-currents (<I>I</I><SUB>ON</SUB>) of back-gated few-layer ambipolar WSe<SUB>2</SUB> FETs are enhanced by about 2 orders of magnitude, and a ∼6× increase in the hole field-effect mobility is observed, the latter primarily resulting from the p-doping-induced narrowing of the Schottky barrier width leading to an enhanced hole injection at the WSe<SUB>2</SUB>/contact metal interface. This (NH<SUB>4</SUB>)<SUB>2</SUB>S(aq) chemical functionalization technique can serve as a model method to control the electronic band structure and enhance the performance of devices based on 2D layered transition-metal dichalcogenides.</P> [FIG OMISSION]</BR>