Optimized Assembly of Micro-/Meso-/Macroporous Carbon for Li–S Batteries

Qiong Tang,Heqin Li,Min Zuo,Jing Zhang,Yiqin Huang,Peiwen Bai,Jiaqi Xu,Kuan Zhou 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.2

In order to explore the effect of hierarchical porous carbon on the performances of Li–S batteries, we synthesized three kinds of micro-/meso-/macroporous carbon materials with different pore properties by facile hard-template method. Different from the majority of reports on porous carbon ensuing large specific surface area (SSA) and total pore volume, it was found that in the case of identically high sulfur content, the pore size distribution substantially influences the performances of Li–S batteries rather than the SSA and total pore volume. Furthermore, in the assembly of micro-/meso-/macropores, the micropore volume ratio to the total pore volume is dominant to the capabilities of batteries. Among the samples, the porous carbon carbonized with the precursor of sucrose at 950℃ presents the highest initial discharge specific capacity of 1327 mAh/g and retention of 630 mAh/g over 100 cycles at 0.2C rate along with the best rate capability. This sample possesses the largest micropore volume ratio of 47.54% but a medium SSA of 1217 m2 /g and inferior total pore volume of 0.54 cm3 /g. The abundant micropores effectively improve the conductivity of dispersed sulfur particles, inhibit the loss of sulfur series and enable the cathode to exhibit superior electrochemical performances.

Effects of Ga-doping on the microstructure and magnetic properties of MnBi alloys

Yang, Yang,Kim, Jong-Woo,Si, Ping-Zhan,Qian, Hui-Dong,Shin, Yongho,Wang, Xinyou,Park, Jihoon,Li, Oi Lun,Wu, Qiong,Ge, Hongliang,Choi, Chul-Jin Elsevier 2018 JOURNAL OF ALLOYS AND COMPOUNDS Vol.769 No.-

<P><B>Abstract</B></P> <P>The low temperature phase Mn<SUB>55</SUB>Bi<SUB>45-<I>x</I> </SUB>Ga<SUB> <I>x</I> </SUB> (<I>x</I> = 0, 1, 3, 5, and 10) alloys were prepared by induction melting process with subsequent low temperature annealing. The effects of Ga-doping on the crystal structure and magnetic properties of the alloys were systematically studied. The room temperature coercivities of Mn<SUB>55</SUB>Bi<SUB>45-<I>x</I> </SUB>Ga<SUB> <I>x</I> </SUB> after ball milling increased from 1.43 T for <I>x</I> = 0 to 1.66 T for <I>x</I> = 5, while the saturation magnetization decreased from 60.7 Am<SUP>2</SUP>/kg (<I>x</I> = 0) to 45.1 Am<SUP>2</SUP>/kg (<I>x</I> = 5). The maximum energy product (<I>BH</I>)<SUB>max</SUB> of Mn<SUB>55</SUB>Bi<SUB>44</SUB>Ga powders reached 7.87 MGOe. The Curie temperature of the Mn<SUB>55</SUB>Bi<SUB>45-<I>x</I> </SUB>Ga<SUB> <I>x</I> </SUB> alloys increased from 633 K to 658 K with increasing Ga concentration in the range of 0 ≤ <I>x</I> ≤ 5.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effects of doping Ga on the microstructural and magnetic properties of MnBi alloy. </LI> <LI> The MnBi-Ga powders are achieved by surfactant assisted high energy ball milling. </LI> <LI> The maximum energy produce (<I>BH</I>)<SUB>max</SUB> shows 7.87 MGOe for Mn<SUB>55</SUB>Bi<SUB>44</SUB>Ga sample. </LI> <LI> The coercivity of Mn<SUB>55</SUB>Bi<SUB>40</SUB>Ga<SUB>5</SUB> after ball milling reached 1.66 T at room temperature. </LI> <LI> The elevated curie temperature (<I>T</I> <SUB>c</SUB>) by doping Ga makes it a possible candidate for high temperature applications. </LI> </UL> </P>

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>

Low-frequency Vibration Suppression Control in a Two-mass System by Using a Torque Feed-forward and Disturbance Torque Observer

Qiong Li,Qiang Xu,Ren Wu 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Given that elastic connection is often used between motor drives and load devices in industrial applications, vibration often occurs at the load side. Vibration suppression is a crucial problem that needs to be addressed to achieve a high-performance servo-control system. Scholars have presented many strategies to suppress vibration. In this study, we propose a method to diminish vibration by using a torque feed-forward and disturbance torque observer. We analyze the system performance and explain the principle of the proposed vibration suppression method based on the transfer functions of the system. The design of controller parameters is another important issue in practical applications. We accordingly provide a succinct outline of the design specifications based on the coefficient diagram method. Furthermore, we build a model under the Simulink environment and conduct experiments to validate the proposed method. Results show that speed and position vibrations are successfully suppressed by the proposed method.

Diffusion of CO2 Molecules in Polyethylene Terephthalate/Polylactide Blends Estimated by Molecular Dynamics Simulations

Li-Qiong Liao,Yi-Zheng Fu,Xiao-Yan Liang,Lin-Yu Mei,Yaqing Liu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.3

Molecular dynamics (MD) simulations have been used to study the diffusion behavior of small gas molecules (CO2) in polyethylene terephthalate (PET)/polylactide (PLA) blends. The Flory-Huggins interaction parameters (χ) determined from the cohesive energy densities are smaller than the critical value of Flory-Huggins interaction parameters (χcritical), and that indicates the good compatibility of PET/PLA blends. The diffusion coefficients of CO2 are determined via MD simulations at 298 K. That the order of diffusion coefficients is correlated with the availably fractional free volume (FFV) of CO2 in the PET/PLA blends means that the FFV plays a vital role in the diffusion behavior of CO2 molecules in PET/PLA blends. The slopes of the log (MSD) as a function of log (t) are close to unity over the entire composition range of PET/PLA blends, which confirmes the feasibility of MD approach reaches the normal diffusion regime of CO2 in PET/PLA blends.

Low-frequency Vibration Suppression Control in a Two-mass System by Using a Torque Feed-forward and Disturbance Torque Observer

Li, Qiong,Xu, Qiang,Wu, Ren The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Given that elastic connection is often used between motor drives and load devices in industrial applications, vibration often occurs at the load side. Vibration suppression is a crucial problem that needs to be addressed to achieve a high-performance servo-control system. Scholars have presented many strategies to suppress vibration. In this study, we propose a method to diminish vibration by using a torque feed-forward and disturbance torque observer. We analyze the system performance and explain the principle of the proposed vibration suppression method based on the transfer functions of the system. The design of controller parameters is another important issue in practical applications. We accordingly provide a succinct outline of the design specifications based on the coefficient diagram method. Furthermore, we build a model under the Simulink environment and conduct experiments to validate the proposed method. Results show that speed and position vibrations are successfully suppressed by the proposed method.

B-cell Lymphoma 2 rs17757541 C>G Polymorphism was Associated with an Increased Risk of Gastric Cardiac Adenocarcinoma in a Chinese Population

Li, Qiong,Yin, Jun,Wang, Xu,Wang, Li-Ming,Shi, Yi-Jun,Zheng, Liang,Tang, Wei-Feng,Ding, Guo-Wen,Liu, Chao,Liu, Rui-Ping,Gu, Hai-Yong,Sun, Jia-Ming,Chen, Suo-Cheng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.7

Aim: Apoptosis has been considered as a fundamental component in cancer pathogenesis, and related genetic factors might play an important role in gastric cardiac adenocarcinoma (GCA) genesis. Methods: We conducted a hospital based case.control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs): BCL2 rs17757541 C>G, BCL2 rs12454712 T>C, FAS rs2234767 G>A, FASL/FASLG rs763110 C>T, ERBB2 rs1136201 A>G and VEGFR2/KDR rs11941492 C>T on the development of GCA. A total of 243 GCA cases and 476 controls were recruited for the study and genotypes were determined using a custom-by-design 48-Plex SNPscan$^{TM}$ Kit. Results: The BCL2 rs17757541 C>G polymorphism was associated with increased risk of GCA. However, there was no significant associations with the other five SNPs. Stratified analyses indicated a significantly increased risk of GCA associated with the BCL2 rs17757541 C>G polymorphism among males, older patients and those with a history of smoking or drinking. Conclusion: These findings indicated that the functional polymorphism BCL2 rs17757541 C>G might contribute to GCA susceptibility. However, our results were limited by small sample size. Future larger studies are required to confirm our current findings.

Research Motion Blurred Image Restoration Algorithms

Qiong Li,Junhui Rao,Xiaofeng Yang 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.9

Subject in the process of image acquisition and the relative games between the camera or camera image fuzzy, it seriously affected the further image feature extraction, target recognition and image analysis. In order to meet the needs of reality, get high quality image, we must be used image restoration techniques for fuzzy image restoration. Based on the detailed study on the basis of the theory of wavelet transform, we confirmed by experiments in motion blurred image of wavelet and decomposition level .The method to identify the fuzzy parameters, under the condition of without noise and with noise on the four classic image restoration algorithm, the simulation experiment using the peak signal-to-noise ratio, mean square error, average gray level gradient method and Laplace operator method of four kinds of image quality evaluation index to evaluate the healing effect and recovery result diagram and its quality evaluation. Through the scene shooting motion blurred image point spread function of parameter identification and image restoration, it demonstrates that the proposed point spread function’s parameters identification method is sound and effective.

Histone acetyltransferase inhibitors antagonize AMP-activated protein kinase in postmortem glycolysis

Qiong Li,Zhongwen Li,Aihua Lou,Zhenyu Wang,Dequan Zhang,Qingwu W. Shen 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.6

Objective: The purpose of this study was to investigate the influence of AMP-activated protein kinase (AMPK) activation on protein acetylation and glycolysis in postmortem muscle to better understand the mechanism by which AMPK regulates postmortem glycolysis and meat quality. Methods: A total of 32 mice were randomly assigned to four groups and intraperitoneally injected with 5-Aminoimidazole-4-carboxamide1-β-D-ribofuranoside (AICAR, a specific activator of AMPK), AICAR and histone acetyltransferase inhibitor II, or AICAR, Trichostatin A (TSA, an inhibitor of histone deacetylase I and II) and Nicotinamide (NAM, an inhibitor of the Sirt family deacetylases). After mice were euthanized, the Longissimus dorsi muscle was collected at 0 h, 45 min, and 24 h postmortem. AMPK activity, protein acetylation and glycolysis in postmortem muscle were measured. Results: Activation of AMPK by AICAR significantly increased glycolysis in postmortem muscle. At the same time, it increased the total acetylated proteins in muscle 45 min postmortem. Inhibition of protein acetylation by histone acetyltransferase inhibitors reduced AMPK activation induced increase in the total acetylated proteins and glycolytic rate in muscle early postmortem, while histone deacetylase inhibitors further promoted protein acetylation and glycolysis. Several bands of proteins were detected to be differentially acetylated in muscle with different glycolytic rates. Conclusion: Protein acetylation plays an important regulatory role in postmortem glycolysis. As AMPK mediates the effects of pre-slaughter stress on postmortem glycolysis, protein acetylation is likely a mechanism by which antemortem stress influenced postmortem metabolism and meat quality though the exact mechanism is to be elucidated.

A Novel Method to Suppress Mid-Frequency Vibrations with a High Speed-Loop Gain for PMSM Control

Li, Qiong,Xu, Qiang,Huang, Shenghua The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

PI controllers are one of the most widely used controllers in industrial control systems due to their simple algorithms and stability. The parameters K_p and K_i determine the performance of the system response. The response is expected to improve by increasing the gain of the PI controller. However, too large a gain will accelerate the speed response and cause vibrations, which is not what is expected. This paper proposes a way to suppress vibrations by detecting the vibration frequency and extracting the vibration signal as a compensation to the speed feedback. Additionally, in order to improve its disturbance rejection ability, a low-order disturbance observer is proposed. This paper also explains the operation principle of the proposed method by analyzing the transfer function and it describes the design of the controller parameters in detail. Simulation and experimental results are provided to verify the merits of the proposed method. These results also show the good performance of the proposed method. It has a rapid response and suppresses vibrations.