First-principles studies of K₁ ₋ _xM_xMgH₃ (M = Li, Na, Rb, or Cs) perovskite hydrides for hydrogen storage

Li, Yuanyuan,Mi, Yiming,Chung, Jin Suk,Kang, Sung Gu Elsevier 2018 International journal of hydrogen energy Vol.43 No.4

<P><B>Abstract</B></P> <P>The structural stability and hydrogen release properties of M-doped KMgH<SUB>3</SUB> (M = Li, Na, Rb, or Cs) were examined using density functional theory (DFT) calculations. The reaction enthalpies (ΔH) of the four possible dehydrogenation reaction pathways were calculated using the doped structures with different phases ( P m 3 ¯ m , P<I>nma</I>, and R3<I>c</I>). The most favorable reaction pathway among these four pathways was found. Among the dopants investigated, the most promising dopant for this reaction was Li. In addition, the application of pressure was found to be useful for tuning the reaction enthalpies of the dehydrogenation reactions. Overall, the results present an efficient means of designing new promising perovskite-type hydrides for hydrogen storage.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Perovskite-type KMgH<SUB>3</SUB> is a promising candidate for hydrogen storage. </LI> <LI> The most favorable reaction pathway of dehydrogenation reactions was examined. </LI> <LI> Li was the most useful and effective dopant to release hydrogen. </LI> <LI> Pressure can be usefully employed for tuning the reaction enthalpies of dehydrogenation reactions. </LI> </UL> </P>

A polymeric composite protective layer for stable Li metal anodes

Guo Suogang,Wang Li,Jin Yuhong,Piao Nan,Chen Zonghai,Tian Guangyu,Li Jiangang,Zhao Chenchen,He Xiangming 나노기술연구협의회 2020 Nano Convergence Vol.7 No.21

Lithium (Li) metal is a promising anode for high-performance secondary lithium batteries with high energy density due to its highest theoretical specific capacity and lowest electrochemical potential among anode materials. However, the dendritic growth and detrimental reactions with electrolyte during Li plating raise safety concerns and lead to premature failure. Herein, we report that a homogeneous nanocomposite protective layer, prepared by uniformly dispersing ­AlPO 4 nanoparticles into the vinylidene fluoride-co-hexafluoropropylene matrix, can effectively prevent dendrite growth and lead to superior cycling performance due to synergistic influence of homogeneous Li plating and electronic insulation of polymeric layer. The results reveal that the protected Li anode is able to sustain repeated Li plating/stripping for > 750 cycles under a high current density of 3 mA cm −2 and a renders a practical specific capacity of 2 mAh cm −2 . Moreover, full-cell Li-ion battery is constructed by using ­LiFePO 4 and protected Li as a cathode and anode, respectively, rendering a stable capacity after 400 charge/discharge cycles. The current work presents a promising approach to stabilize Li metal anodes for next-generation Li secondary batteries.

Aqueous Processing and Effects of V2O5 on Microwave Dielectric Properties of Multilayer Li1.075Nb0.625Ti0.45O3 Ceramics

Shaochun Li,Yongjuan Geng,Tiejun Zhao,Zuquan Jin,Peng Zhang 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.1

In the present work, we report the development of an aqueous tape casting method and a low temperature co-firing process for fabrication of multilayer Li1.075Nb0.625Ti0.45O3 microwave dielectric ceramics. A co-binder, consisting of polyvinyl acetate latex (PVAc) and polyvinyl alcohol (PVA), was used to prepare aqueous Li1.075Nb0.625Ti0.45O3 tapes. PVA addition increased the tape flexibility and adhesiveness but resulted in decreased tensile strength. Rheological tests indicated that the aqueous ceramic slurry exhibited a typical shear thinning behavior without thixotropy, suitable for tape casting. Scanning electron microscopy (SEM) studies revealed that the green tapes have a defect-free surface and that the multilayer ceramics sintered at 900°C have a fine plate like, grainy microstructure of uniform size. At lower temperatures, increased densification rates were achieved by addition of V2O5 to Li1.075Nb0.625Ti0.45O3 ceramics. The saturated bulk densities and dielectric constants (εr) of Li1.075Nb0.625Ti0.45O3 multilayer ceramics affected by lower sintering temperatures with an increase in V2O5 doping, and then an improvement in the quality factor (Q × f value) of the samples was achieved at the lower sintering temperatures. As a result, the εr of 64.9 and the Q × f value of 8800 GHz were obtained in the sample with an addition of 3 wt. % V2O5, sintered at a temperature of 900°C. No reaction was observed between the ceramic and silver layers when sliver inner-electrode, was sintered with ceramic tapes at 900°C.

Four new compounds from the bulbs of Lycoris aurea with neuroprotective effects against CoCl2 and H2O2-induced SH-SY5Y cell injuries

An Jin,Xuelian Xiang,Yun-Yun Zhu,Heng-Yi Yu,Hui-Fang Pi,Peng Zhang,Han-Li Ruan 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.3

Three new alkaloids, 2a-hydroxy-6-O-n-butyloduline,O-n-butyllycorenine, (-)-N-(chloromethyl)lycoramine(1–3), and a new phenolic compound, ((7S)-7-(4-hydroxyphenyl)-7-hydroxypropyl)-20-methylbenzene-30,60-diol (14), along with ten known alkaloids (4–13), wereisolated from the bulbs of Lycoris aurea collected fromHuaihua County of Hunan Province, China. Their structureswere elucidated by spectroscopic methods includingHRESIMS, UV, IR, and NMR. All the isolated compoundswere tested for their neuroprotective effects against CoCl2and H2O2-induced SH-SY5Y cell death. Compounds 1–7and 10 exhibited significant neuroprotective effects againstCoCl2-induced SH-SY5Y cell injury, while compounds1–5, 7, 10 and 12 showed obvious neuroprotective effectsagainst H2O2-induced SH-SY5Y cell death.

A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

Li, Qingwei,Chen, Fang,Zhao, Weili,Xu, Mingxiu,Fang, Benjie,Zhang, Yuelong,Duo, Liping,Jin, Yuqi,Sang, Fengting Korean Chemical Society 2007 Bulletin of the Korean Chemical Society Vol.28 No.10

Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near- IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gasliquid- solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.

Carbon-coated SnO₂@C with hierarchically porous structures and graphite layers inside for a high-performance lithium-ion battery

Li, Yao,Zhu, Shenmin,Liu, Qinglei,Gu, Jiajun,Guo, Zaiping,Chen, Zhixin,Feng, Chuanliang,Zhang, Di,Moon, Won-Jin The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.6

<P>A high-performance anode material was prepared from a hierarchically structured activated carbon which contains <I>in situ</I> graphene and nano-graphite. The activated carbon was immersed in a solution of SnCl<SUB>2</SUB>·2H<SUB>2</SUB>O and subjected to ultrasound. As a result, nanoparticles of SnO<SUB>2</SUB> were uniformly deposited on the surface of the activated carbon. The composite material was then coated with a thin layer of carbon by soaking it in a sucrose solution, followed by carbonization of the adsorbed sucrose at 500 °C. The resulting composite showed an outstanding high-rate cycling performance that can deliver an initial discharge capacity of 1417 mAh g<SUP>−1</SUP> and maintain a discharge capacity of more than 400 mAh g<SUP>−1</SUP> after 100 cycles at a high current density of 1000 mA g<SUP>−1</SUP>. This outstanding electrochemical performance is likely to be related to a unique combination of the excellent electrical conductivity of the activated carbon with graphite layers formed inside, its hierarchical pore structure which enhances lithium-ion transportation, and the carbon coating which alleviates the effects of volume changes, shortens the distance for Li<SUP>+</SUP> diffusion, facilitates the transmission of electrons, and keeps the structure stable.</P> <P>Graphic Abstract</P><P>Carbon-coated SnO<SUB>2</SUB>@C nanocomposite with hierarchically porous structures and graphite layers inside was prepared by ultrasound and hydrothermal treatment, which showed an outstanding high-rate cycling performance for lithium-ion battery. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1jm14290a'> </P>

Evidence for the medicinal value of Squama Manitis (pangolin scale): A systematic review

Xinyao Jin,Hui Zi Chua,Keyi Wang,Nan Li,Wenke Zheng,Wentai Pang,Fengwen Yang,Bo Pang,Mingyan Zhang,Junhua Zhang 한국한의학연구원 2021 Integrative Medicine Research Vol.10 No.1

Background: Squama Manitis (pangolin scale) has been used in traditional Chinese medicine for thousands of years. However, its efficacy has not been systematically reviewed. This review aims to fill the gap. Methods: We searched six electronic databases including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure Database (CNKI), WanFang Database and SinoMed from inception to May 1, 2020. Search terms included “pangolin”, “Squama Manitis”, “Manis crassicaudata”, “Manis javanica”, “Malayan pangolins”, “Manis pentadactyla”, “Ling Li”, “Chuan Shan Jia”, “Shan Jia”, “Pao Jia Zhu”, “Jia Pian” and “Pao Shan Jia”. The Cochrane Risk of Bias (RoB) assessment tool and Newcastle-Ottawa Scale (NOS) were used to evaluate the risk of bias of the included randomized controlled trials (RCTs) and case control studies (CCSs). Results: After screening, 15 articles that met the inclusion criteria were finally included. There were 4 randomized controlled trials, 1 case control study, 3 case series and 7 case reports. A total of 15 different diseases were reported in these studies, thus the data could not be merged to generate powerful results. Two RCTs suggested that Squama Manitis combined with herbal decoction or antibiotics could bring additional benifit for treating postpartum hypogalactia and mesenteric lymphadenitis. However, this result was not reliable due to low methodological quality and irrational outcomes. The other two RCTs generated negative results. All the non-RCTs did not add any valuable evidence to the efficacy of Squama Manitis beacause of small samples, incomplete records, non-standardized outcome detection. In general, currently available evidence cannot support the clinical use of Squama Manitis. Conclusion: There is no reliable evidence that Squama Manitis has special medicinal value. The removal of Squama Manitis from Pharmacopoeia is rational.

A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

Qingwei Li*,Fang Chen,Weili Zhao,Mingxiu Xu,Benjie Fang,Yuelong Zhang,Liping Duo,Yuqi Jin,Fengting Sang 대한화학회 2007 Bulletin of the Korean Chemical Society Vol.28 No.10

Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near-IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gas-liquid-solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.

Aprotic and Aqueous Li–O₂ Batteries

Lu, Jun,Li, Li,Park, Jin-Bum,Sun, Yang-Kook,Wu, Feng,Amine, Khalil American Chemical Society 2014 Chemical reviews Vol.114 No.11

<P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/chreay/2014/chreay.2014.114.issue-11/cr400573b/production/images/medium/cr-2013-00573b_0033.gif'></P>

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.