RESULTS ON THE ALGEBRAIC DIFFERENTIAL INDEPENDENCE OF THE RIEMANN ZETA FUNCTION AND THE EULER GAMMA FUNCTION

Xiao-Min Li,Yi-Xuan Li 대한수학회 2023 대한수학회보 Vol.60 No.6

In 2010, Li-Ye \cite[Theorem 0.1]{LiYe2010} proved that \begin{equation}\nonumber P\left(\zeta(z),\zeta'(z),\ldots,\zeta^{(m)}(z),\Gamma(z),\Gamma'(z),\Gamma^{''}(z)\right) \not\equiv 0\quad\text{in }\ \mathbb{C}, \end{equation} where $m$ is a non-negative integer, and $P(u_{0},u_{1}, \ldots, u_{m},v_{0},v_{1},v_{2})$ is any non-trivial polynomial in its arguments with coefficients in the field $\mathbb{C}$. Later on, Li-Ye \cite[Theorem 1]{LiYe2016} proved that \begin{equation}\nonumber P\left(z,\Gamma(z),\Gamma'(z),\ldots,\Gamma^{(n)}(z), \zeta(z)\right)\not\equiv 0 \end{equation} in $z\in \mathbb{C}$ for any non-trivial distinguished polynomial $P(z,u_0, u_1,\ldots$, $u_n, v)$ with coefficients in a set $L_\delta$ of the zero function and a class of non-zero functions $f$ from $\mathbb{C}$ to $\mathbb{C}\cup\{\infty\}$ (cf.~\cite[Definition 1]{LiYe2016}). In this paper, we prove that $P\left(z,\zeta(z),\zeta'(z),\ldots,\zeta^{(m)}(z),\Gamma(z),\Gamma'(z),\ldots,\Gamma^{(n)}(z)\right)\not\equiv 0$ in $z\in\mathbb{C}$, where $m$ and $n$ are two non-negative integers, and $$P(z, u_0,u_1,\ldots,u_m,v_0,v_1,\ldots,v_n)$$ is any non-trivial polynomial in the $m+n+2$ variables $$u_0,u_1,\ldots,u_m,v_0,v_1,\ldots,v_n$$ with coefficients being meromorphic functions of order less than one, and the polynomial $P(z, u_0,u_1,\ldots,u_m,v_0,v_1,\ldots,v_n)$ is a distinguished polynomial in the $n+1$ variables $v_0,v_1,\ldots, v_n$. The question studied in this paper is concerning the conjecture of Markus from \cite{Markus2007}. The main results obtained in this paper also extend the corresponding results from Li-Ye \cite{LiYe2008} and improve the corresponding results from Chen-Wang \cite{Chen2021} and Wang-Li-Liu-Li \cite{Wang2021}, respectively.

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.

Improved lithium storage performance of CeO2-decorated SrLi2Ti6O14 material as an anode for Li-ion battery

Ying Li,Hong-Yan Liu,Ling-Na Shi,Yan-Rong Zhu,Ting-Feng Yi 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

In this work, the CeO2-decorated SrLi2Ti6O14 anode was successfully prepared through a solid-state process. The space-charge effect induced by the internal adsorption of ions on the CeO2 surface can easilyresult in a formation of an excellent conductive interfacial layer between CeO2 and SrLi2Ti6O14. The goodelectrical contact between CeO2 and SrLi2Ti6O14 offers more active sites for the electrolyte storage andredox reaction, and promotes the intercalation/deintercalation of lithium ions, and thus improves therate performance and cycle stability. Due to its unique structure and composition, the CeO2-decoratedSrLi2Ti6O14 composites exhibit high reversible capacities, good cycle performance and outstanding rateperformance. Especially, the CeO2 (5 wt%)-decorated SrLi2Ti6O14 anode shows the most excellent electrochemicalperformance, which delivers a large charge capacity of 121.3 mAh g 1 and a capacity retentionof 94.48% after 100 cycles at 0.5 A g 1. However, the corresponding charge capacity and capacity retentionof pristine SrLi2Ti6O14 are 100.5 mAh g 1 and 86.77%, respectively. The CeO2(5 wt%)-decoratedSrLi2Ti6O14 with enhanced rate capacity, cycle stability and structural stability is a potential electrodematerial candidate for Li-ion battery.

Tumor acidity and CD44 dual targeting hyaluronic acid-coated gold nanorods for combined chemo- and photothermal cancer therapy

Li, Yi,Duy Le, Thai Minh,Nam Bui, Quang,Yang, Hong Yu,Lee, Doo Sung Elsevier 2019 Carbohydrate polymers Vol.226 No.-

<P><B>Abstract</B></P> <P>In this work, tumor acidity and CD44 dual targeting hyaluronic acid-coated gold nanorods (AuNRs) are investigated for combined chemo- and photothermal cancer therapy. Low molecular weight hyaluronic acid (LMWHA) is conjugated with pH-sensitive groups for pH-induced aggregation and lipoic acid for coating of AuNRs. By changing pH-sensitive groups with different pKa values, pH-sensitivity of modified LMWHA can be tuned. After coating modified LMWHA onto AuNRs, biocompatibility of the AuNRs is significantly improved. These LMWHA-coated AuNRs can gradually aggregate under slightly acidic conditions, making them favorable for accumulation at acidic tumor sites. Surface LMWHA allows the nanocomposites to be selectively uptaken by CD44-expressing cancer cells, and AuNRs endows the nanocomposites with excellent photothermal ability. Loading of doxorubicin, a chemical drug, provides the LMWHA-coated AuNRs synergistic cancer cell-killing (<I>in vitro</I>) and tumor growth inhibiting (<I>in vivo</I>) ability. Taken together, these results demonstrate that this multifunctional nanosystem with pH-induced aggregation and CD44 targeting has potential for combined chemo- and photothermal cancer therapy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Conjugation of pH-sensitive groups induces acidity-triggered aggregation. </LI> <LI> Surface coating of hyaluronic acid allows selective tumor targeting of nanoparticles. </LI> <LI> Co-delivery of chemical drugs and gold nanorods enables combined cancer therapy. </LI> </UL> </P>

On-demand supply of slurry fuels to a porous anode of a direct carbon fuel cell: Attempts to increase fuel-anode contact and realize long-term operation

Li, Chengguo,Yi, Hakgyu,Lee, Donggeun Elsevier 2016 Journal of Power Sources Vol.309 No.-

<P><B>Abstract</B></P> <P>In this paper, we propose a novel idea that might allow resolution of the two biggest challenges that hinder practical use of direct carbon fuel cells (DCFC). This work involved 1) the use of three types of porous Ni anode with different pore sizes, 2) size matching between the anode pores and solid fuel particles in a molten-carbonate (MC) slurry, and 3) provision of a continuous supply of fuel-MC slurry through the porous Ni anode. As a result, larger numbers of smaller pores in the anode were preferred for extending the triple phase boundary (TPB), as long as the fuel particles were sufficiently small to have full access to the inner pore spaces of the anode. For example, the maximal power density achieved in the case of optimal size matching, reached 645 mW cm<SUP>−2</SUP>, which is 14-times greater than that for the case of poorest size-matching and 64-times larger than that for a non-porous anode, and lasted for more than 20 h. After 20 h of steady operation at a fixed current density (700 mA cm<SUP>−2</SUP>), the electric potential slightly decreased due to partial consumption of the fuel. The cell performance readily recovered after restarting the supply of MC-fuel slurry.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A potentially continuous fuel supply with increasing fuel-anode contacts in a DCFC. </LI> <LI> Of importance was the size match between the anode pores and fuel particles. </LI> <LI> Maximal power density under the optimal size-matching reached 645 mW cm<SUP>−2</SUP>. </LI> <LI> More than 20-h steady operation was achieved at a current density of 700 mA cm<SUP>−2</SUP>. </LI> </UL> </P>

Pollen record of the mid- to late-Holocene centennial climate change on the East coast of South Korea and its influential factors

Song, Bing,Yi, Sangheon,Jia, Hongjuan,Nahm, Wook-Hyun,Kim, Jin-Cheul,Lim, Jaesoo,Lee, Jin-Young,Sha, Longbin,Mao, Limi,Yang, Zhongyong,Nakanishi, Toshimichi,Hong, Wan,Li, Zhen Elsevier 2018 Journal of Asian earth sciences Vol.151 No.-

<P><B>Abstract</B></P> <P>To understand historical climate change in western Pacific coastal areas, a sediment core (SOJ-2) from the stable sedimentary environment of the Songjiho Lagoon on the east coast of South Korea was obtained for centennial-resolution palynological analysis. The ages of the SOJ-2 core is well controlled by carbon 14 dating with high-resolution accelerator mass spectrometry (AMS), and the results indicated a general warm to cold climate trend from the mid-Holocene to the present, which can be divided into two different stages: a warmer stage between 6842 and 1297 cal yr BP and a colder stage from 1297 cal yr BP to the present, with fluctuations during these stages. The climate was wetter from 6842 to 6227 cal yr BP and 4520 to 1297 cal yr BP and was drier from 6227 to 4520 cal yr BP. The climate changed to cold and dry during the period from 1297–425 cal yr BP. The impact of human activity on the climate began at approximately 1297 cal yr BP and became pronounced starting in 425 cal yr BP. The general cooling trend may represent a response to decreasing solar insolation; however, the relative dryness or wetness of the climate may have been co-determined by westerlies and the East Asian summer monsoon (EASM). The climate had a teleconnection with the North Atlantic region, resulting from changes in solar activity. Nevertheless, EI Niño–Southern Oscillation (ENSO) activity played an important role in impacting the EASM changes in western Pacific coastal areas.</P> <P><B>Highlights</B></P> <P> <UL> <LI> There is a centennial resolution climate record from 6842 cal yr BP to present. </LI> <LI> The general cooling trend was probably triggered by decreasing solar insolation. </LI> <LI> The precipitation was co-determined by westerlies and the East Asian Summer Monsoon. </LI> <LI> The ENSO activity may be an important factor for East Asian Summer Monsoon change. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Impact of high-temperature-water cooling damage on the mechanical properties of concrete

Zhai, Yue,Li, Yan,Li, Yubai,Wang, Siwei,Liu, Yi,Song, Ki-Il Elsevier 2019 Construction & building materials Vol.215 No.-

<P><B>Abstract</B></P> <P>A series of impact tests were conducted on split Hopkinson pressure bar equipment to study the influence of high-temperature-cooling damage on the mechanical properties of concrete. The experimental investigation showed the influence on the peak stress, peak strain, and fracture mode. The results indicate that the strain rate is directly related to the loading rate and heating temperature. The test results of natural cooling and water immersion cooling treatment were compared, which showed that the strength of water-cooled specimens is higher than that of naturally cooled specimens before the heating temperature reaches 400 °C and becomes much lower when the heating temperature is higher than 400 °C. Based on the experimental study, a dynamic non-linear elastic constitutive equation was established using a particle swarm optimization algorithm and an inversion analysis method. These results could provide theoretical references for the design of the ultimate strength of concrete materials for practical applications, such as fire and explosion prevention.</P> <P><B>Highlights</B></P> <P> <UL> <LI> High temperature-cooling damage on mechanical properties for concrete is tested. </LI> <LI> The strain rate is directly related to the loading rate and heating temperature. </LI> <LI> 400 °C can be considered as the threshold of high temperature-water cooling damage. </LI> <LI> Dynamic non-linear elastic constitutive equation is established. </LI> </UL> </P>

Deubiquitination and Stabilization of PD-L1 by CSN5

Lim, Seung-Oe,Li, Chia-Wei,Xia, Weiya,Cha, Jong-Ho,Chan, Li-Chuan,Wu, Yun,Chang, Shih-Shin,Lin, Wan-Chi,Hsu, Jung-Mao,Hsu, Yi-Hsin,Kim, Taewan,Chang, Wei-Chao,Hsu, Jennifer L.,Yamaguchi, Hirohito,Ding Elsevier 2016 Cancer cell Vol.30 No.6

<P><B>Summary</B></P> <P>Pro-inflammatory cytokines produced in the tumor microenvironment lead to eradication of anti-tumor immunity and enhanced tumor cell survival. In the current study, we identified tumor necrosis factor alpha (TNF-α) as a major factor triggering cancer cell immunosuppression against T cell surveillance via stabilization of programmed cell death-ligand 1 (PD-L1). We demonstrated that COP9 signalosome 5 (CSN5), induced by NF-κB p65, is required for TNF-α-mediated PD-L1 stabilization in cancer cells. CSN5 inhibits the ubiquitination and degradation of PD-L1. Inhibition of CSN5 by curcumin diminished cancer cell PD-L1 expression and sensitized cancer cells to anti-CTLA4 therapy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> TNF-α stabilizes cancer cell PD-L1 in response to chronic inflammation </LI> <LI> Activation of NF-κB by TNF-α induces CSN5 expression leading to PD-L1 stabilization </LI> <LI> CSN5 enzyme activity controls T cell suppression via PD-L1 deubiquitination </LI> <LI> Destabilization of PD-L1 by CSN5 inhibitor curcumin benefits anti-CTLA4 therapy </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>

Ideal tensile strength and shear strength of ZrO₂(111)/Ni(111) ceramic-metal Interface: A first principle study

Guo, Xingye,Zhang, Yi,Jung, Yeon-Gil,Li, Li,Knapp, James,Zhang, Jing Elsevier 2016 Materials & Design Vol.112 No.-

<P><B>Abstract</B></P> <P>The ideal mechanical strengths of ZrO<SUB>2</SUB>(111)/Ni(111) ceramic-metal (C-M) interface are calculated through simulated tensile and shear deformations using the first principles calculations. The structures of ZrO<SUB>2</SUB>(111)/Ni(111) interfaces with 1- and 3-layer Ni thicknesses are optimized and the mechanical properties are investigated. For tensile deformation in [111] direction, the Young's moduli of the 1-layer Ni and 3-layer Ni M-C models are 139.9GPa and 60.2GPa, respectively; and ultimate tensile strengths are 11.6GPa and 7.9GPa, respectively. For shear deformation in {111} ⟨110⟩ system, the shear moduli of the 1-layer Ni and 3-layer Ni M-C models are 43.9GPa and 30.4GPa, respectively; and ultimate shear strengths are 7.0GPa and 3.0GPa, respectively. For shear deformation in {111} ⟨11 2 − ⟩ system, the shear moduli of the 1-layer Ni and 3-layer Ni M-C models are 30.9GPa and 17.3GPa, respectively; and ultimate shear strengths are 6.0GPa and 1.8GPa, respectively. Overall, 1-layer Ni C-M interface models have better mechanical properties than those of 3-layer models. The observed strengths are explained by using charge distribution, electron localization function, and Bader charge transfer analyses. The results are important for designing robust thermal barrier coating through optimizing bond coat thickness.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ideal tensile and shear strengths of ZrO2/Ni interface are calculated using DFT. </LI> <LI> Stress-strain curves of interfaces in tensile and shear deformations are calculated. </LI> <LI> 1-layer Ni interface models have higher mechanical strengths than 3-layer models. </LI> <LI> Charge density and Bader charge analyses are conducted to explain the strengths. </LI> </UL> </P> <P><B>Graphic abstract</B></P> <P>[DISPLAY OMISSION]</P>

Perspectives in <i>in situ</i> transmission electron microscopy studies on lithium battery electrodes

Lee, Hyun-Wook,Li, Yuzhang,Cui, Yi Elsevier Science B.V.Amsterdam 2016 Current opinion in chemical engineering Vol.12 No.-

<P> <I>In situ</I> transmission electron microscopy (TEM) has emerged as a promising characterization tool for the observation of nanoscale processes in lithium ion batteries. TEM offers direct visualization of lithiation during electrochemical reaction combined with atomic spatial and temporal resolution imaging, selected area diffraction (SAD), electron energy-loss spectroscopy (EELS), and energy dispersive X-ray spectroscopy (EDS). This review highlights recent progress on <I>in situ</I> TEM studies on lithium ion battery electrodes associated with open and closed cell configurations. The advantages and challenges of each cell configuration are addressed. These techniques allow for new discoveries and a better fundamental understanding of energy related technologies.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>In situ</I> TEM has observed nanoscale processes in lithium ion batteries. </LI> <LI> Many new phenomena have been visualized with the clearest evidence. </LI> <LI> Recent progress associated with open and closed cell configurations was reviewed. </LI> <LI> Development of TEM technology will shed light on <I>in situ</I> TEM on battery chemistry. </LI> </UL> </P>