Nanostructured carbon-based cathode catalysts for nonaqueous lithium–oxygen batteries

Li, Qing,Cao, Ruiguo,Cho, Jaephil,Wu, Gang The Royal Society of Chemistry 2014 Physical chemistry chemical physics Vol.16 No.27

<P>Although lithium-ion batteries are traditionally considered to be the most promising candidate for electrochemical energy storage owing to their relatively long cycle life and high energy efficiency, their limited energy density as well as high cost are still causing a bottleneck for their long-term applications. Alternatively, rechargeable Li–O<SUB>2</SUB> batteries have the potential to practically provide 3–5 times the gravimetric energy density of conventional Li-ion batteries. However, the lack of advanced electrode design and efficient electrocatalysts for oxygen reduction–evolution reactions remains as one of the grand challenges before this technology can be commercialized. Among various catalyst formulations, nanocarbon composite materials have been recognized as the most promising ones for Li–O<SUB>2</SUB> batteries because of their reasonable balance among catalytic activity, durability, and cost. In this perspective, the recent progress in the development of nanostructured carbon-based electrocatalysts for nonaqueous Li–O<SUB>2</SUB> batteries is discussed, including metal-free carbon catalysts, transition-metal–nitrogen–carbon composite catalysts, and transition-metal-compounds/nanocarbon catalysts. The morphology–performance correlations of these catalysts are highlighted, aiming to provide guidance for rationally designing advanced catalysts.</P> <P>Graphic Abstract</P><P>Structure–activity correlations of nanocarbon oxygen cathode catalysts for nonaqueous Li–O<SUB>2</SUB> batteries are discussed, providing guidance for rational catalyst design. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4cp00225c'> </P>

Structural, magnetic and dielectric properties of (Li1+, Al3+) co-doped Ni0.5Zn0.5Fe2O4 ferrite ceramics prepared by the sol-gel auto-combustion method

Qing Ni,Li Sun,Ensi Cao,Wentao Hao,Yongjia Zhang,Lin Ju 한국물리학회 2020 Current Applied Physics Vol.20 No.9

(Li1+, Al3+) co-doped Ni0.5Zn0.5Fe2O4 ferrites, Ni0.5-xZn0.5-xLixAlxFe2O4 (x = 0.000, 0.025, 0.050 and 0.100), were synthesized by the sol-gel auto-combustion method. X-ray diffraction (XRD), field emission scanning electronic microscope (FESEM), vibrating sample magnetometer (VSM) and LCR meter were used to investigate the structural, magnetic and dielectric properties. Results of XRD and SEM indicate that both doping amount and calcination temperature play significant roles in crystal structure and grain growth. Also, it can be observed that the saturation magnetization and the coercivity change in a noticeable manner. The Ni0.475Zn0.475Li0.025Al0.025Fe2O4 ferrite sintered at 1200 °C has a relatively low coercivity value (62.93 Oe) and the largest saturation magnetization (110.95 emu/g). Besides, dielectric behavior is also improved by Li1+ and Al3+ co-doping

Modeling, Preparation, and Elemental Doping of Li₇La₃Zr₂O₁₂ Garnet-Type Solid Electrolytes: A Review

Cao, Shiyu,Song, Shangbin,Xiang, Xing,Hu, Qing,Zhang, Chi,Xia, Ziwen,Xu, Yinghui,Zha, Wenping,Li, Junyang,Gonzale, Paulina Mercedes,Han, Young-Hwan,Chen, Fei The Korean Ceramic Society 2019 한국세라믹학회지 Vol.56 No.2

Recently, all-solid-state batteries (ASSBs) have attracted increasing interest owing to their higher energy density and safety. As the core material of ASSBs, the characteristics of the solid electrolyte largely determine the performance of the battery. Thus far, a variety of inorganic solid electrolytes have been studied, including the NASICON-type, LISICON-type, perovskite-type, garnet-type, glassy solid electrolyte, and so on. The garnet Li₇La₃Zr₂O₁₂ (LLZO) solid electrolyte is one of the most promising candidates because of its excellent comprehensively electrochemical performance. Both, experiments and theoretical calculations, show that cubic LLZO has high room-temperature ionic conductivity and good chemical stability while contacting with the lithium anode and most of the cathode materials. In this paper, the crystal structure, Li-ion transport mechanism, preparation method, and element doping of LLZO are introduced in detail based on the research progress in recent years. Then, the development prospects and challenges of LLZO as applied to ASSBs are discussed.

A Study on the Strategic Implications from Successful Sharing Economy Companies as a Distribution Platform in Korea

Li,Qing-Zhu,Lee,Jong-Ho 한국유통과학회 2019 KODISA ICBE (International Conference on Business Vol.2019 No.-

The concept of sharing economy(shared economy) is being interested in Korea especially. Many related companies are interested in its concept, situation, successful cases and methods suitable for real world. At that point, it is necessary to look for or investigate them in detail. Similarly, in Korea, too. Therefore, the purposes of this study are as follows. First, to review and define the concept of sharing economy from both previous literature studies and successful companies including their leaders. Second, to analyze market status in detail and find out what is the problem to make better or what is good point fit for situation. Third, to make research and provide their strategic implications for related companies

Protective effects of vitamins C and E on dichlorodiphenyltrichloroethane-induced genotoxicity and hepatotoxicity in human liver cells

Xiao Ting Jin,Li Song,Xiang Yuan Liu,Hang Qing Li,Long Cheng,Zhuo Yu Li1,,Z. Y. Li 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.2

Dichlorodiphenoxytrichloroethane (DDT), a persistent organic pollutant and hepatotoxicant, is used to control the malaria. However, scarce information exists on relevant effective inhibitors of DDT’ toxicity. The aim of this study was to investigate protective effects of natural antioxidants vitamin C (VC) or/and vitamin E (VE) on p,pʹ-DDT-induced genotoxicity and hepatotoxicity in human liver cells. p,pʹ-DDT exposure increased levels of chromatin condensation, comet parameter, micronucleus induction and DPC coefficient of HL-7702 cells in a dose-dependent manner. Also, an increase in mRNA levels of CYP1A1 as well as CYP3A4, and a decrease in UGT along with GST were observed. Interestingly, supplementation with VC or/and VE prevented p,pʹ-DDT-caused alterations in DNA damage and phase metabolism gene expressions, and the combination of VC and VE had a more protective effect than VC or VE alone. These findings illustrated that VC or/and VE could be beneficial for the alleviation of p,pʹ-DDT-incurred toxicity in human liver cells.

Neutrophil Count and the Inflammation-based Glasgow Prognostic Score Predict Survival in Patients with Advanced Gastric Cancer Receiving First-line Chemotherapy

Li, Qing-Qing,Lu, Zhi-Hao,Yang, Li,Lu, Ming,Zhang, Xiao-Tian,Li, Jian,Zhou, Jun,Wang, Xi-Cheng,Gong, Ji-Fang,Gao, Jing,Li, Jie,Li, Yan,Shen, Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.2

Purpose: To explore the value of systemic inflammatory markers as independent prognostic factors and the extent these markers improve prognostic classification for patients with inoperable advanced or metastatic gastric cancer (GC) receiving palliative chemotherapy. Methods: We studied the prognostic value of systemic inflammatory factors such as circulating white blood cell count and its components as well as that combined to form inflammation-based prognostic scores (Glasgow Prognostic Score (GPS), Neutrophil-Lymphocyte Ratio (NLR), Platelet Lymphocyte Ratio (PLR), Prognostic Index (PI) and Prognostic Nutritional Index (PNI)) in 384 patients with inoperable advanced or metastatic gastric cancer (GC) receiving first-line chemotherapy. Univariate and multivariate analyses were performed to examine the impact of inflammatory markers on overall survival (OS). Results: Univariate analysis revealed that an elevated white blood cell, neutrophil and/or platelet count, a decreased lymphocyte count, a low serum albumin concentration, and high CRP concentration, as well as elevated NLR/PLR, GPS, PI, PNI were significant predictors of shorter OS. Multivariate analysis demonstrated that only elevated neutrophil count (HR 3.696, p=0.003) and higher GPS (HR 1.621, p=0.01) were independent predictors of poor OS. Conclusion: This study demonstrated elevated pretreatment neutrophil count and high GPS to be independent predictors of shorter OS in inoperable advanced or metastatic GC patients treated with first-line chemotherapy. Upon validation of these data in independent studies, stratification of patients using these markers in future clinical trials is recommended.

Sublethal effects of beta-cypermethrin on the bird cherry-oat aphid Rhopalosiphum padi (Hemiptera: Aphididae)

Qing-Qing Zhang,Wen-Qiang Li,Zeng-Bin Lu,Li-Li Li,Yi Yu,Chao Li,Xing-Yuan Men 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

Rhopalosiphum padi is a sap-sucking aphid and an important pest of wheat that causes considerable yield loss. Beta-cypermethrin, a synthetic pyrethroid pesticide, has a broad insecticide spectrum and is considered effective for aphid control, while its residual concentrations may have sublethal effects on R. padi. Here, the sublethal effects of beta-cypermethrin on R. padi were conducted under laboratory conditions. The acute toxicity test showed that LC 10 , LC 20 , and LC 25 of beta-cypermethrin to R. padi adults were 0.003, 0.031 and 0.079 mg L −1 , respectively. The pre-adult survival rate was significantly reduced by all three concentrations. LC 20 significantly extended the development duration of 1st instar nymphs, pre-oviposition period, and oviposition period of R. padi. The adult longevity was also reduced by LC 25 . However, the fecundity did not differ between the betacypermethrin treatment and control. For life table parameters, both the finite rate (λ) and intrinsic rate of increase (r) decreased at LC 10 and LC 20 , as well as the net reproductive rate (R 0 ) reduced at LC 10 and LC 25 , while mean generation time (T) increased at LC 20 . Thus, at the concentrations of beta-cypermethrin tested here, there were negative impacts on R. padi fitness by decreased pre-adult survival rate, λ, r, and R 0 , and delayed the development of some stages and increased T.

Correlations among Six Hormone-Induced Transcription Factors and the Alcohol Acyltransferase Gene in Apple

Qing-Qing Li,JIN SHENG,Pengcheng Li,Dapeng Li,Cheng-Chao Zheng,Dequan Li,Huairui Shu 한국식물학회 2012 Journal of Plant Biology Vol.55 No.4

Alcohol acyltransferase (AAT) plays an important role in ester biogenesis in ripening fruit. In apple, MdAAT2 is up-regulated in response to treatment with defense-related hormones. We cloned a novel MdAAT2 promoter via thermal asymmetric interlaced PCR (TAIL-PCR). Sequence analysis indicated the presence of salicylic acid (SA)- and methyl jasmonate (MeJA)-responsive elements in the promoter region. To examine further the operational mechanism for transcription factors (TFs) in regulating expression of the MdAAT2 promoter, we isolated and investigated six potential stress-induced TFs -- MdMYB1, MdMYB2, MdMYB6,MdERF1, MdERF2, and WRKY. These were monitored during various stages of fruit development as well as under several hormonal treatments. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that all of these TF genes, as well as MdAAT2, were detectable in the stigmas. Levels of expression by MdMYB1, MdMYB2, and MdERF1were significantly correlated with that by MdAAT2 during fruit ontogeny. Moreover, transcription of three TFs (MdMYB1,MdMYB6, and MdERF1) was significantly correlated with that of MdAAT2 upon exposure to ethephon, SA, or MeJA. Sequence analysis demonstrated that CAAT, CCAAT elements,and several MYB transcription factor binding sites (CNGTTmotif,AACCA, and CTAACCA elements) existed in the MdAAT2 promoter region. Using that analysis, we performed modeling of MdMYB1 and MdMYB6 based on PROTEINDNA complex1 and complex3 (PDB Accession Numbers 1H88 and 1H8A). There, similarities were found with the protein complex of CAAT or CCAAT consensus sequences. Thus, we propose that two TFs -- MdMYB1 and MdMYB6-- are directly or indirectly involved in the activation of MdAAT2 expression in apple fruit.

A large-area free-standing graphene oxide multilayer membrane with high stability for nanofiltration applications

Chen, Long,Li, Yanhui,Chen, Lina,Li, Na,Dong, Chenglong,Chen, Qiong,Liu, Beibei,Ai, Qing,Si, Pengchao,Feng, Jinkui,Zhang, Lin,Suhr, Jonghwan,Lou, Jun,Ci, Lijie Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.345 No.-

<P><B>Abstract</B></P> <P>A flexible and free-standing graphene oxide and nylon 6 (GO@nylon 6) multilayer nanofiltration membrane was prepared by a layer-by-layer assembly process. The combination of electrospinning and electrospraying technique was employed, which can facilely prepare large-area membrane with size of 20 × 30 cm. The mechanical stability of multilayer membrane has enhanced significantly due to the tightly locked structure achieved by nylon 6 nanofibers network. The novel GO@nylon 6–13 multilayer nanofiltration membrane demonstrated a pure water flux up to 11.15 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP>, while keeping high organic dye rejection rate (>95% for methylene blue, and >99% for methyl orange). The rejections rate of the Na<SUB>2</SUB>SO<SUB>4</SUB>, NaCl, CuSO<SUB>4</SUB>, and Pb(NO<SUB>3</SUB>)<SUB>2</SUB> were 56.5%, 27.6%, 36.7%, and 18.9%, respectively. Furthermore, GO@nylon 6–13 multilayer nanofiltration membrane also demonstrated a high flux of some common organic solvents (8.4, 5.3, and 0.8 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP> for methanol, ethanol, and NMP, respectively), showing excellent chemical stability for separation process in those solvents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Large-area GO@nylon 6 multilayer nanofiltration membrane was prepared. </LI> <LI> The multilayer structure enhances the mechanical stability. </LI> <LI> The multilayer membrane demonstrates a high water flux. </LI> <LI> The multilayer membrane shows high rejection rate for organic dyes. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Photograph and cross-section SEM image of GO@nylon 6 multilayer nanofiltration membrane, the inset shows the water contact angle.</P> <P>[DISPLAY OMISSION]</P>

In-situ synthesized ZnFe₂O₄ firmly anchored to the surface of MWCNTs as a long-life anode material with high lithium storage performance

Yang, Tianbo,Zhang, Wanxi,Li, Linlin,Jin, Bo,Jin, Enmei,Jeong, Sangmoon,Jiang, Qing Elsevier 2017 APPLIED SURFACE SCIENCE - Vol.425 No.-

<P><B>Abstract</B></P> <P>Because of two different metal cations in the crystal structures, binary transition metal oxides possess a lot of unique properties. ZnFe<SUB>2</SUB>O<SUB>4</SUB> emerges from these transition metal oxides on account of its high theoretical capacity (1072mAhg<SUP>−1</SUP>). One-dimensional multi-walled carbon nanotubes (MWCNTs) would be a desirable conductive additive for ZnFe<SUB>2</SUB>O<SUB>4</SUB>, thereby improving the electrochemical performance of ZnFe<SUB>2</SUB>O<SUB>4</SUB>. In this work, we prepare ZnFe<SUB>2</SUB>O<SUB>4</SUB>/MWCNTs by solvothermal method with further heat-treatment. ZnFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles are firmly anchored to the surface of MWCNTs. ZnFe<SUB>2</SUB>O<SUB>4</SUB>/MWCNTs nanocomposite displays high specific capacity (1278mAhg<SUP>−1</SUP> at a current density of 200mAg<SUP>−1</SUP> after 200 cycles, and 565mAhg<SUP>−1</SUP> at a current density of 1500mAg<SUP>−1</SUP> after 500 cycles), and good rate performance (367mAhg<SUP>−1</SUP> even at a current density of 6000mAhg<SUP>−1</SUP> after 80 cycles). The superior electrochemical performance may promote ZnFe<SUB>2</SUB>O<SUB>4</SUB> to be a promising alternative anode in lithium-ion batteries.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ZnFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles and ZnFe<SUB>2</SUB>O<SUB>4</SUB>/MWCNTs composites have been prepared by a facile solvothermal method. </LI> <LI> ZnFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles are firmly anchored to the surface of MWCNTs. MWCNTs can suppress the growth of ZnFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles. </LI> <LI> ZnFe<SUB>2</SUB>O<SUB>4</SUB>/MWCNTs nanocomposite displays high specific capacity at a high current density. </LI> </UL> </P>