The effect of molecular solvents on the viscosity, conductivity and ionicity of mixtures containing chloride anion-based ionic liquid

Qiwei Yang,Huabin Xing,Kun Yu,Baogen Su,Zongbi Bao,Yiwen Yang,Qilong Ren 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.5

Chloride anion-based ionic liquids (ILs) have unique importance among various ILs. Nevertheless, they are usually very viscous, and the study on their mixtures with molecular solvent is important for their practical application. In this work, the viscosities and conductivities of the binary mixtures of 1-butyl-3-methylimidazolium chloride and several protic/aprotic solvents were measured, and the underlying information about intermolecular interaction and microscopic structure was discussed. The result showed that the molecular solvents which have relatively high dielectric constant and hydrogen-bond acidity will be more efficient in promoting the dissociation of chloride anion-based ILs and improving the transport properties of corresponding applications.

Template-free synthesis of hierarchical NiO microtubes as high performance anode materials for Li-ion batteries

Yiwen Hong,Jingxia Yang,Jingli Xu,최원묵 한국물리학회 2019 Current Applied Physics Vol.19 No.6

Hierarchical nanostructured NiO (h-NiO) microtubes were prepared by a simple wet-chemical synthesis without the use of template or surfactant, followed by the calcination of α-Ni(OH)2 precursor. The structural characterization of the h-NiO microtubes were performed by scanning microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD), the results of which indicated that the obtained h-NiO microtubes are covered by the nanosheet grown perpendicularly on the tube surface. The unique hierarchical nanostructure of h-NiO microtubes with high surface area and many voids facilitates the electrochemical reaction as well as the short ion and electron transport pathway. Therefore, as anode electrode of Li-ion batteries, the h- NiO microtubes deliver largely enhanced cycle capacity of 770 mAh·g−1 at a current density of 0.5 C after 200 cycles with high columbic efficiency, compared to the NiO rods. These results suggest that the h-NiO microtubes can be a promising anode material for Li-ion batteries.

Investigation of the Effect Mechanism of Cutting Sequence on Spiral Milling of CFRP/Ti Laminates Under Ultrasonic-Assisted Conditions

Kai Yang,Jie Pan,Ziyang Cao,Yiwen Zhu 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.25 No.4

The hole-making mechanism of carbon fiber reinforced plastic (CFRP)/titanium alloy stacks is different from that of monolayer materials. In order to reveal the effects of different cutting sequence strategies on the hole-making quality and machining efficiency of the stacked materials, valuable insights are provided for the design of the stacking machining process and the selection of the most suitable cutting sequence. The researchers conducted ultrasonic vibration-assisted helical milling and conventional helical milling experiments with different milling parameters, and explored the basic influence mechanisms of CFRP → Ti and Ti → CFRP on the hole-making in both ways. The results show that different cutting sequences have significant effects on the axial force and chip morphology changes during CFRP/Ti stack machining. The dimensional accuracy and consistency of the holes cut from the Ti side are better, and the quality of the entrance and exit from the Ti side under the ultrasonically assisted condition is close to the quality level of the holes cut from the CFRP side under the normal helical milling, and the ultrasonically assisted condition plays a good role in improving the quality of the holes made. In addition, the tearing coefficients of CFRP hole entry/exit in both machining modes increased with the increase of feed per tooth in tangential direction and decreased with the increase of spindle speed. The tearing coefficients of entry/exit holes in CFRP direction were smaller than those in titanium direction.

Extracellular products-mediated interspecific interaction between Pseudomonas aeruginosa and Escherichia coli

Yuan Yang,Li Jing,Lin Jiafu,Pan Wenjuan,Chu Yiwen,Prithiviraj Balakrishnan,Guo Yidong,Wang Xinrong,Zhao Kelei 한국미생물학회 2021 The journal of microbiology Vol.59 No.1

The Gram-negative pathogen Pseudomonas aeruginosa adopts several elaborate strategies to colonize a wide range of natural or clinical niches and to overcome the neighboring bacterial competitors in polymicrobial communities. However, the relationship and interaction mechanism of P. aeruginosa with other bacterial pathogens remains largely unexplored. Here we explore the interaction dynamics of P. aeruginosa and Escherichia coli, which frequently coinfect the lungs of immunocompromised hosts, by using a series of on-plate proximity assays and RNA-sequencing. We show that the extracellular products of P. aeruginosa can inhibit the growth of neighboring E. coli and induce a large-scale of transcriptional reprogramming of E. coli, especially in terms of cellular respiration- related primary metabolisms and membrane components. In contrast, the presence of E. coli has no significant effect on the growth of P. aeruginosa in short-term culture, but causes a dysregulated expression of genes positively controlled by the quorum-sensing (QS) system of P. aeruginosa during subsequent pairwise culture. We further demonstrate that the divergent QS-regulation of P. aeruginosa may be related to the function of the transcriptional regulator PqsR, which can be enhanced by E. coli culture supernatant to increase the pyocyanin production by P. aeruginosa in the absence of the central las-QS system. Moreover, the extracellular products of E. coli promote the proliferation and lethality of P. aeruginosa in infecting the Caenorhabditis elegans model. The current study provides a general characterization of the extracellular products-mediated interactions between P. aeruginosa and E. coli, and may facilitate the understanding of polymicrobial infections.

Preparation and Photoelectrocatalytic Performance Study of Au-RGO/TiO2 NTs Photoelectrode

Zuo Jin Long,ShaoDong Yang,YiWen Li,Chong Tan,Zhi Xia,SiYing Yuan,ShiYou Yu,JunSheng Li 한국고분자학회 2022 Macromolecular Research Vol.30 No.11

In our research, The Au-reduced graphene oxide (RGO)/TiO2 nanotubes (NTs) photoelectrode was prepared by electrodeposition, and was characterized and analyzed by scanning electron microscope, X-ray energy scattering spectroscopy, X-ray diffraction, photoluminescence spectroscopy, and photoelectrochemical methods. The results show that the best preparation conditions is setting deposition voltage as 0.2 V and deposition time as 30 s. At the same time, the nano-gold is well supported on RGO/TiO2 NTs without changing the original nanotube array structure. After a 35 W mercury lamp and a 15 V bias are applied, the photoelectric degradation efficiency of methylene blue is 72%, slightly higher thanthose of the other two electrodes. which show demonstrate that the photocatalytic activity of Au-RGO/TiO2 NTs photoelectrodes under visible light is improved effectively.

Electroless Cu/Ni Plating on Graphite Flake and the Effects to the Properties of Graphite Flake/Si/Al Hybrid Composites

Ying Huang,Xuanyi Peng,Yiwen Yang,Haiwei Wu,Xu Sun,Xiaopeng Han 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.5

Proper process and parameter were investigated to coat Cu or Ni on graphite fl ake (G f ) by electroless plating. Microstructuralcharacterization indicated that the Cu/Ni was coated on the G f uniformly and comprehensively. Then aluminum matrixcomposites reinforced with Si and graphite were fabricated by a unique vacuum gas pressure infi ltration. The thermal conductivityand mechanical properties of the composites, both with and without Cu or Ni coating layers on the graphite surface,have been studied. The obtained results indicated that the mechanical property of the Cu or Ni coated G f /Si/Al compositesdramatically increased, as compared with the non-coated G f /Si/Al composite. In the meantime, Cu or Ni coated G f provedto have better wettability and interfacial bonding with the aluminum matrix, which were expected to be a highly sustainableand dispersible reinforcement for metal matrix composites.

Severe Cutaneous Adverse Reactions: A Single-Center Retrospective Study of 173 Patients in China

( Zhongyi Xu ),( Jie Shen ),( Yiwen Yang ),( Ruoyue Yuan ),( Leihong Flora Xiang ),( Chengfeng Zhang ) 대한피부과학회 2019 Annals of Dermatology Vol.31 No.5

Background: Severe cutaneous adverse reactions (SCAR) to drugs are a crucial public health issue and the use of systemic corticosteroids in SCAR has been controversial. Objective: To analyze clinical features, causative drugs, treatment, outcomes, and prognostic factors of SCAR in the case-series of 173 patients, and add more information to the debate of using systemic corticosteroids in SCAR management. Methods: A retrospective study of 173 SCAR patients diagnosed with drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) or acute generalized exanthematous pustulosis (AGEP) at a tertiary care institution in China between January 2014 and December 2017 was conducted. Results: Of 173 patients, allopurinol, carbamazepine, and antibiotics are the most frequently implicated drugs for DRESS (40.4%), SJS/TEN (26.0%), and AGEP (40.0%) respectively. Moreover, there is a strongly negative correlation between early corticosteroids use and the progression (p=0.000) and severity (p=0.01) of skin lesions. However, there is no association between early corticosteroids use and the mortality of SCAR (odds ratio: 1.01, 95% confidence interval: 0.95∼1.08). In addition, lymphadenopathy, eosinophilia, and interval from onset to corticosteroids treatment were correlated with SCAR prognosis. Conclusion: Prompt short-course systemic corticosteroids use is associated with early-stage skin lesions remission without influencing the disease mortality. Lymphadenopathy and eosinophilia were the independent poor prognostic factors of SCAR. (Ann Dermatol 31(5) 545∼ 554, 2019)

Observations on the ultrastructure of extrusomes in the hypotrichous ciliate Architricha indica (Protist, Ciliophora)

Xiaocui Zhang,Xinpeng Fan,Linying Yang,Yiwen Wang,Bing Ni,Saleh A. Al-Farraj,Fukang Gu 한국통합생물학회 2014 Animal cells and systems Vol.18 No.2

Extrusomes of different categories in ciliates have been suggested to have different structures and functions. To investigate the characteristics of extrusomes in the hypotrichous ciliate, we examined Architricha indicausing scanning and transmission electron microscopy and electron microscopic enzymo-cytochemistry. Theresults showed that the mature extrusomes were ellipsoidal vesicles with structureless cavities on their anteriorparts and arranged in rows beneath the pellicle; the extruded structures of extrusomes were cyathiform and canremain outside of the cell surface after extrusion. These findings differ distinctly from that of previouslyreported extrusomes in other ciliates and thus suggest a new type of extrusomes. These organelles originatedfrom endoplasmic reticulum in the deeper part of the cytoplasm, underwent a serious of development,gradually migrated to the cortical cytoplasm and finally positioned in their functional areas. In contrast withlower forms of ciliates, density, arrangement, and localization of extrusomes in A. indica showed obviousdifferences between the ventral and dorsal surface of cells. This may be in some way related to thedifferentiation of the dorsoventral cortex, and functional ciliature happened to the hypotrichous ciliates. Inaddition, the extrusomes may perform protective or defensive function, which associates with the activity ofmitochondria and contributes to the pellicle retrieval or renewal.

Facile Fabrication of Superhydrophobic Cellulose/Fe2O3-STA Film with Nanoflower Morphologies for Heavy Oil Removal

Chang-Lian Xu,Shiyi Wang,Lu Zhou,Yiwen Bi,Gang Yang,Jun Wu,Xiaohong Zhang 한국섬유공학회 2022 Fibers and polymers Vol.23 No.10

Heavy oils induced water pollutions are difficult to be eliminated due to the oils located under water. Herein, wefabricated superhydrophobic cellulose film with nanoflower structures via a Facile method to eliminate heavy oil from water. Cellulose films were in-situ modified with Fe2O3 and stearic acid (STA) for superhydrophobic modification. Thecorresponding superhydrophobic cellulose/Fe2O3-STA film has water contact angle of 155.5 º and sliding angle of 5.5 º, andcan maintains its superhydrophobicity when it is immersed in water. The film exists excellent self-cleaning property, and thedusts on the film could be easily swept away by running water drops. The film was further applied to separate heavy oil/watermixture with separation efficiency of 99.37 %, and the separation efficiency was maintained after 20 separation cycles aswell. The film can also be utilized to absorb small heavy oil drops under water. Thus, we not only develop a simple way toproduce superhydrophobic cellulose based films, but also provide superhydrophobic materials to solve water pollutioncaused by heavy oil.

Encainide, a class Ic anti-arrhythmic agent, blocks voltage-dependent potassium channels in coronary artery smooth muscle cells

Hongliang Li,Yue Zhou,Yongqi Yang,Yiwen Zha,Bingqian Ye,Seo-Yeong Mun,Wenwen Zhuang,Jingyan Liang,Won Sun Park The Korean Society of Pharmacology 2023 The Korean Journal of Physiology & Pharmacology Vol.27 No.4

Voltage-dependent K⁺ (Kv) channels are widely expressed on vascular smooth muscle cells and regulate vascular tone. Here, we explored the inhibitory effect of encainide, a class Ic anti-arrhythmic agent, on Kv channels of vascular smooth muscle from rabbit coronary arteries. Encainide inhibited Kv channels in a concentration-dependent manner with an IC₅₀ value of 8.91 ± 1.75 μM and Hill coefficient of 0.72 ± 0.06. The application of encainide shifted the activation curve toward a more positive potential without modifying the inactivation curve, suggesting that encainide inhibited Kv channels by altering the gating property of channel activation. The inhibition by encainide was not significantly affected by train pulses (1 and 2 Hz), indicating that the inhibition is not use (state)-dependent. The inhibitory effect of encainide was reduced by pretreatment with the Kv1.5 subtype inhibitor. However, pretreatment with the Kv2.1 subtype inhibitor did not alter the inhibitory effects of encainide on Kv currents. Based on these results, encainide inhibits vascular Kv channels in a concentration-dependent and use (state)-independent manner by altering the voltage sensor of the channels. Furthermore, Kv1.5 is the main Kv subtype involved in the effect of encainide.