Recent Developments in the Effects of Different Dopants on the Structure and Property of Lithium Titanate Material

Xi-Yang Li,Qian-Lin Chen,Min Yang,Ya-Nan Li,Jing-Bo Ma 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.3

The lithium titanium spinel Li4Ti5O12 has attracted more and more attention as anode materials applied in lithium ion batteries. Li4Ti5O12 material has been found to be able to intercalate lithium ions without deformation of the lattice. However, compared with graphite and other anode materials, the low conductivity of Li4Ti5O12 restricts its charging and discharging rate. Doping is deemed to be a businesslike method to enhance ionic and electronic conductivity of Li4Ti5O12. This paper reviews the effects of Li4Ti5O12 with different doping ions on different crystal lattice states. And it has been found by a summary that the doping objective of doping ions at Li4Ti5O12 is also different. Moreover, the applications of ion doping in different fields of Li4Ti5O12 are prospected.

The effect of S-functionalized and vacancies on V2C MXenes as anode materials for Na-ion and Li-ion batteries

Ya-Meng Li,Yong-Liang Guo,Zhao-Yong Jiao 한국물리학회 2020 Current Applied Physics Vol.20 No.2

The electrochemical properties of V2C and V2CT2 (T = O, S) MXenes with and without vacancy as anode materials for Na-ion and Li-ion batteries, have been studied using first-principles calculation. The present results indicate that the adsorption strength of Li-ion and Na-ion on V2CS2 are less than that of O-functionalized, together with a lower diffusion barrier. Simultaneously, V2CS2 monolayer exhibits lower open-circuit voltage (OCV) values of 0.72 and 0.49 V for Li- and Na-ion, respectively. Interestingly, the presence of atomic vanadium vacancy on V2CS2 monolayer exerts more prominent effects on enhancing adsorption strength than that of carbon vacancy for Li-ion and Na-ion, but with an exception for the diffusion of Li-ion and Na-ion on V2CS2 monolayer. The finding suggests that the V2CS2 monolayer is expected to be a potential candidate as anode material for Li-ion and Na-ion battery due to its lower open-circuit voltages and diffusion barriers.

Controllable Synthesis of Co-Doped Spinel LiMn2O4 Nanotubes as Cathodes for Li-Ion Batteries

Li-Xin Zhang,Yuan-Zhong Wang,Hong-Fang Jiu,Ya-Lei Wang,Yi-Xin Sun,Zhenzhong Li 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.2

Spinel Co-LiMn2O4 nanotubes have been synthesized via solid state reaction using α-MnO2 nanotubes as selftemplates. The as-prepared powders were investigated by XRD, TEM, and galvanostatic discharge/charge analysis. The optimal doping amount was confirmed by galvanostatic charge/discharge measurements. The results indicate that about 67% of initial capacity (115 mAh/g) of LiMn2O4 nanotubes can be retained after 50 cycles. For Co-LiMn2O4 nanotubes, the initial reversible capacity is 126.6 mAh/g and 100 mAh/g can be maintained after 50 cycles. The capacitance retention rate of Co-LiMn2O4 nanotubes is as high as 79%. These results indicate that the doping Co can effectively improve circle stability and electrochemical performance of LiMn2O4 nanotubes.

Cloning and Characterization of a Na+/H+ Antiporter Gene of the Moderately Halophilic Bacterium Halobacillus aidingensis AD-6T

Ya Jie Zou,Li Fu Yang,Lei Wang,Su Sheng Yang 한국미생물학회 2008 The journal of microbiology Vol.46 No.4

A gene encoding a Na+/H+ antiporter was obtained from the genome of Halobacillus aidingensis AD-6T, which was sequenced and designated as nhaH. The deduced amino acid sequence of the gene was 91% identical to the NhaH of H. dabanensis, and shared 54% identity with the NhaG of Bacillus subtilis. The cloned gene enable the Escherichia coli KNabc cell, which lack all of the major Na+/H+ antiporters, to grow in medium containing 0.2 M NaCl or 10 mM LiCl. The nhaH gene was predicted to encode a 43.5 kDa protein (403 amino acid residues) with 11 putative transmembrane regions. Everted membrane vesicles prepared from E. coli KNabc cells carrying NhaH exhibited Na+/H+ as well as Li+/H+ antiporter activity, which was pH-dependent with the highest activity at pH 8.0, and no K+ /H+ antiporter activity was detected. The deletion of hydrophilic C-terminal amino acid residues showed that the short C-terminal tail was vital for Na+/H+ antiporter activity.

陳映眞文學硏究

劉麗雅 한국중국문화학회 1993 中國學論叢 Vol.2 No.-

Electrochemical Cr(VI) reduction using a sacrificial Fe anode: Impacts of solution chemistry and stoichiometry

Chuang, Sheng-Ming,Ya, Vinh,Feng, Chiao-Lin,Lee, Shou-Jen,Choo, Kwang-Ho,Li, Chi-Wang Elsevier 2018 Separation and purification technology Vol.191 No.-

<P><B>Abstract</B></P> <P>A systematic investigation of Cr(VI) reduction using electrochemical reduction revealed that the Cr(VI) reduction was extremely fast with reaction kinetics limited by the anodic generation of Fe(II). The Cr(VI) reduction rate increased with decreasing pH at the initial stage of reaction but the time to reach complete Cr(VI) reduction is pH independent. The amount of Fe(II) generated per mole of Cr(VI) reduced was calculated and compared with the stoichiometric value, i.e., 3mole of Fe(II) needed per mole of Cr(VI) reduced. The values are 11.1% higher than the stoichiometric value for pH 7 and 9, but are 32.0% less for pH 3 and 5. The spontaneous reduction of Cr(VI) by Fe<SUP>0</SUP> and adsorption of Cr(VI) to Fe(OH)<SUB>3</SUB> precipitates might contribute the additional Cr(VI) removal. Effect of DO was investigated under various mixing schemes. Under N<SUB>2</SUB> purging, Fe(II) generated for one mole of Cr(VI) reduced is 3.67% higher than the stoichiometric value, while mechanic mixing and aeration mixing show 15% and 19%, respectively, higher than stoichiometric value, indicating that DO does impact Cr(VI) reduction. The electrochemical Cr(VI) reduction process was also employed to treat electroplating wastewater with and without pH pre-adjustment, achieving 100% total Cr and Ni removal for both cases. ORP can be used as a controlling parameter when electrochemical reduction is implemented for Cr(VI) reduction.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effect of current on Cr(VI) reduction under same current density was studied. </LI> <LI> Effects of initial and fixed pH on Cr(VI) reduction were investigated. </LI> <LI> Effect of DO on Cr(VI) reduction was explored. </LI> <LI> Electrochemical reduction was applied for treating electroplating wastewater. </LI> <LI> ORP is an ideal parameter for controlling electrochemical Cr(VI) reduction. </LI> </UL> </P>

Electrochemical treatment for simultaneous removal of heavy metals and organics from surface finishing wastewater using sacrificial iron anode

Ya, Vinh,Martin, Natacha,Chou, Yi-Hsuan,Chen, Yi-Ming,Choo, Kwang-Ho,Chen, Shiao-Shing,Li, Chi-Wang Elsevier 2018 Journal of the Taiwan Institute of Chemical Engine Vol.83 No.-

<P><B>Abstract</B></P> <P>Surface finishing wastewater having low pH (∼2) and high conductivity (>11 mS/cm) was treated by electrocoagulation (EC) or electrochemical Fenton (ECF) processes using sacrificial iron anodes. Under the same theoretical Fe dosage, the effects of electrolytic time, initial pH, and current density on the simultaneous removal of organic and heavy metal were investigated. A complete metal removal was achieved even at the low current density of 24.2 mA/cm<SUP>2</SUP> and short electrolytic time of 4 min, whereas approximately 40% of chemical oxygen demand was removed. Increasing the electric current density did not improve removal efficiencies, but consumed more electric energy. Low current conditions produced a brown color sludge associated with ferric hydroxide. On the contrary, a greenish color sludge was created at a high current due to the formation of ferrous hydroxide. The formation of ferrous hydroxide impacted the treated water quality. The ECF was employed to overcome the low COD removal by the EC, achieving >67% of COD removal. The costs of ECF processes were slightly greater than that of chemical coagulation, but achieving a lot greater heavy metal removals. ECF process can be a promising method for simultaneous removal of heavy metal and organics from complex industrial wastewater.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Organics and metal removals by electrochemical treatments using Fe were studied. </LI> <LI> Fe(II)/Fe(III) distribution depended on current density, reaction time, and solution pH. </LI> <LI> The lower in electric current density, the better in energy efficiency. </LI> <LI> Electrochemical Fenton enhanced organic removal unachieved by electrocoagulation. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Scrap iron packed in a Ti mesh cage as a sacrificial anode for electrochemical Cr(VI) reduction to treat electroplating wastewater

Ya, Vinh,Guillou, Esther Le,Chen, Yi-Ming,Yu, Jui-Hsuan,Choo, Kwang-Ho,Chuang, Sheng-Ming,Lee, Shou-Jen,Li, Chi-Wang Elsevier 2018 JOURNAL- TAIWAN INSTITUTE OF CHEMICAL ENGINEERS Vol.87 No.-

<P><B>Abstract</B></P> <P>A novel sacrificial anode comprised of scrap iron packed inside a cage made of titanium mesh was developed for Cr(VI) reduction. With electric currents applied, the surface passivation of scrap iron electrode could be avoided. Due to the large surface area with open structures provided, the applied current densities (1.18–3.54 mA/cm<SUP>2</SUP>) were low, resulting in low operating voltage and energy consumption. Complete Cr(VI) removal was achieved with electric currents applied, whereas only 20% of the Cr(VI) was removed without electricity. Direct Cr(VI) reduction on the iron surface was a dominant mechanism for the system operated at low (0.25 A) or no current. Acidic pH levels were more effective in Cr(VI) removal, due to more adsorption of Cr(VI) onto the precipitated Fe hydroxide. The trend in total Cr removal was almost the same as that of Cr(VI) removal, but time required to complete total Cr removal was extended. With intermittent electricity supply at a high electric current intensity, the energy consumption of the system was more efficient. Using scrap iron as a sacrificial anode under the intermittent current condition can save 72–77% of the total operational costs required by the conventional plate electrode.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel anode packed with scrap iron inside a Ti mesh was used for reducing Cr(VI). </LI> <LI> Electroplating wastewater containing Cr(VI) and Ni(II) was treated. </LI> <LI> Current intensity and initial pH affect the Cr(VI) reduction pattern significantly. </LI> <LI> Intermittent but high electric current supply saved 72–77% of the operating costs. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

The Impact of Public Pension on Chinese Household Consumption

Ya-Hao LI(Ya-Hao LI),Fan YANG(Fan YANG),Shuang ZHANG(Shuang ZHANG) 한국웰빙융합학회 2024 웰빙융합연구 Vol.7 No.1

Purpose: The improvement of the social security system can greatly affect residents' future uncertainty, and it is important to study the relationship between public pensions and household consumption. Research design, data and methodology: Using the 2018 China Household Panel Survey (CFPS) data, the instrumental variable method is used to analyze the impact of pension insurance on urban residents' consumption. Results: The results of the study show that there are differences in the impact of three different pension insurance systems on household consumption. The pension insurance for public sector significantly boosts household consumption, and having a pension insurance for public sector can increase household consumption by 7.7%. The pension insurance for enterprise employee will reduce household consumption, but this is only significant for urban households. The pension insurance for urban and rural residents has a negative impact on household consumption. For the 16- to 39-year-old group, having a pension insurance for urban and rural residents will reduce household consumption by 5.7%. At the same time, household income, assets, scale, and education level will positively stimulate household consumption. Conclusions: The study reveals varying impacts among different pension types, highlighting the need for optimizing social security schemes to incentivize higher consumption rates.

FISH MEAL REPLACEMENT BY FERMENTED MIXTURE CONTAINING SOYBEAN MEAL AND EARTHWORM MEAL, Eisenia foetida IN DIET OF WHITE SHRIMP, Litopenaeus vannamei

Ya-Li Shiu,Shieh-Tsung Chiu,Chiu-Hsia Chiu,Chun-Hung Liu 한국수산과학회 양식분과 2015 한국수산과학회 양식분과 학술대회 Vol.2015 No.5