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>

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>

Fitness is Recovered with the Decline of Dimethachlon Resistance in Laboratoryinduced Mutants of Sclerotinia sclerotiorum after Long-term Cold Storage

Jin-Li Li,Feng-Ci Wu,Fu-Xing Zhu 한국식물병리학회 2015 Plant Pathology Journal Vol.31 No.3

After four years of cold storage, dimethachlon resistance of two laboratory-induced resistant Sclerotinia sclerotiorum isolates SCG7 and LA50 declined by 99.5% and 98.9%, respectively, and cross resistance to iprodione and procymidone also declined dramatically. Along with the decline of fungicide resistance, osmotic sensitivity to sodium chloride and glucose decreased tremendously; mycelial growth rate, sclerotia number and weight per potato dextrose agar (PDA) plate increased on average by 118.6%, 85. 5% and 64.5%, respectively; and virulence to detached leaves of oilseed rape increased by 72.7% on average. Significant negative correlations were detected between dimethachlon resistance levels and mycelial growth rate on PDA (r = -0.980, P = 0.021), and between resistance levels and lesion diameters on detached leaves of oilseed rape plants (r = -0.997, P = 0.002). These results have profound implications for assessing the potential risk for resistance development to dicarboximide fungicides in S. sclerotiorum.

Isolation of New Strain of Cordyceps militaris HB8 and Optimal Condition for Production of Adenosine and Cordycepin in Fruit Body

Li, Jin Feng,Hoang, Van An,Ahn, Jong Chan,Yang, Dong Uk,Lee, Dong Wook,Yang, Deok Chun The Plant Resources Society of Korea 2020 한국자원식물학회지 Vol.33 No.6

Cordyceps has been used in traditional Chinese medicine more than 2000 year ago. In this study, the new Cordyceps militaris was founded and isolated from O-dae mountain in Korea, and was identified its genetic characteristics. The newly isolation strain HB8 was most closet to Cordyceps militaris W141449 (99.82%), Cordyceps militaris JLCY-LI819 (99.82%) and Cordyceps militaris 4642 (99.81%), respectively. the genotypic result was show that train HB8 was belonging to the Cordyceps militaris genus, therefore, Cordycep militaris HB8 proposed with accession number MT835161. This study we find the optimal condition for production of cordycepin from Cordyceps militaris HB8 was 8 mg/g (200 g of pupa, 1 g of KH₂PO₄, 0.5 g of K₂HPO₄, 20 g of glucose, 1 g of MgSO₄, 0.05 g of vitamin B1, and 1 mg of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h) and the optimum condition for the production of adenosine was 2.6 mg/g (15 g of skim milk powder, 1 g of KH₂PO₄, 0.5 g of K₂HPO₄, 20 g of glucose, 1 g of MgSO₄, 0.05 g of vitamin B1, and 1 mg of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h).

Research on the motion characteristics of a trans-media vehicle when entering water obliquely at low speed

Li, Yong-li,Feng, Jin-fu,Hu, Jun-hua,Yang, Jian The Society of Naval Architects of Korea 2018 International Journal of Naval Architecture and Oc Vol.10 No.2

This paper proposes a single control strategy to solve the problem of trans-media vehicle difficult control. The proposed control strategy is just to control the vehicle's air navigation, but not to control the underwater navigation. The hydrodynamic model of a vehicle when entering water obliquely at low speed has been founded to analyze the motion characteristics. Two methods have been used to simulate the vehicle entering water in the same condition: numerical simulation method and theoretical model solving method. And the results of the two methods can validate the hydrodynamic model founded in this paper. The entering water motion in the conditions of different velocity, different angle, and different attack angle has been simulated by this hydrodynamic model and the simulation has been analyzed. And the change rule of the vehicle's gestures and position when entering water has been obtained by analysis. This entering water rule will guide the follow-up of a series of research, such as the underwater navigation, the exiting water process and so on.

Macroporous Inverse Opal-like Mo_<i>x</i>C with Incorporated Mo Vacancies for Significantly Enhanced Hydrogen Evolution

Li, Feng,Zhao, Xianglong,Mahmood, Javeed,Okyay, Mahmut Sait,Jung, Sun-Min,Ahmad, Ishfaq,Kim, Seok-Jin,Han, Gao-Feng,Park, Noejung,Baek, Jong-Beom American Chemical Society 2017 ACS NANO Vol.11 No.7

<P>The hydrogen evolution reaction (HER) is one of the most important pathways for producing pure and clean hydrogen. Although platinum (Pt) is the most efficient HER electrocatalyst, its practical application is significantly hindered by high cost and scarcity. In this work, an MoxS with incorporated Mo vacancies and macroporous inverse opal-like (IOL) structure (MoxC-IOL) was synthesized and studied as a low-cost efficient HER electrocatalyst. The macroporous IOL structure was controllably fabricated using a facile-hard template strategy. As a result of the combined benefits of the Mo vacancies and structural advantages, including appropriate hydrogen binding energy, large exposed surface, robust IOL structure and fast mass/charge transport, the synthesized MoxC-IOL exhibited significantly enhanced HER electrocatalytic performance with good stability, with performance comparable or superior to Pt wire in both acidic and alkaline solutions.</P>

Boosting oxygen reduction catalysis with abundant copper single atom active sites

Li, Feng,Han, Gao-Feng,Noh, Hyuk-Jun,Kim, Seok-Jin,Lu, Yalin,Jeong, Hu Young,Fu, Zhengping,Baek, Jong-Beom The Royal Society of Chemistry 2018 Energy & environmental science Vol.11 No.8

<P>With their high catalytic activity, stability, selectivity, and 100% atom utilization, single atomic non-noble metal based materials are valuable alternatives to efficient but expensive Pt based catalysts. For efficient catalysis, single-atom catalysts must expose abundant single atomic metal active centers. Here, we report the rational design and synthesis of a Cu single-atom catalyst with high Cu content of over 20.9 wt%, made of single atomic Cu anchored into an ultrathin nitrogenated two-dimensional carbon matrix (Cu-N-C). The high Cu content was achieved by the introduction of additional N species, which can securely trap and protect the Cu atoms. During oxygen reduction, the single atomic Cu exhibited over 54 times higher mass activity than metallic Cu nanoparticles at a potential of 0.85 V <I>versus</I> a reversible hydrogen electrode (RHE). Furthermore, the Cu-N-C exhibited 3.2 times higher kinetic current at 0.85 V (<I>vs.</I> RHE), and a much lower Tafel slope (37 mV dec<SUP>−1</SUP>), as well as better methanol/carbon monoxide tolerance and long-term stability than commercial Pt/C. Density functional theory (DFT) calculations reveal that the Cu active sites exhibit improved O-O bond stretching and favorable adsorption energies of O2 and OOH for four-electron oxygen reduction.</P>

Identification of MicroRNAs as potential biomarkers for detecting ischemic stroke

Li Kexin,Shen Li,Zheng Pingping,Wang Yanjun,Wang Lijuan,Meng Xiaoli,Lv Yaogai,Xue Zhiqiang,Guo Xin,Zhang Anning,Pan Pan,Bi Chunli,Chen Yang,Feng Tianyu,Li Bo,Jin Lina,Yao Yan 한국유전학회 2022 Genes & Genomics Vol.44 No.1

Background: Increasing epidemic of ischemic stroke (IS) makes it urgent to understand the pathogenesis and regulatory mechanism, previous studies have described microRNAs (miRNAs) is part of the brain's response to ischemia. Objective: The aim of this study was to screen potential biomarkers for the prediction and novel treatment of IS. Methods: Differentially expressed miRNAs were screened from three newly diagnosed IS patients and three controls by RNA sequencing technology. Furthermore, target prediction databases were then used to analysis the target genes of different expressed miRNAs, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were used to identify the functions and the main biochemical and signal pathways of differentially expressed target genes. Results: Our results revealed that 27 miRNAs were differentially expressed in IS, among which, hsa-miR-659-5p was the most highly increased and was first found to be associated with IS. In addition, KEGG pathway analyses showed that differentially expressed miRNAs were mainly significantly enriched in lysosome pathway, cytokine-cytokine receptor interaction pathway, spliceosome pathway, base excision repair pathway. Conclusions: miRNAs were involved in IS pathogenesis, and hsa-miR-659-5p, hsa-miR-151a-3p and hsa-miR-29c-5p as the three highest |log2FoldChange| regulation in this study, which may be the biomarkers of IS and need further study.

Transcriptome profiling of Shindongjin and Sugary mutant at grain-filling stages using RNA-Seq

Feng-Peng Li,Min-Young Yoon,Gang Li,Yong-Jin Park 한국육종학회 2013 한국육종학회 심포지엄 Vol.2013 No.07

Rice (Oryza sativa) is an excellent model monocot with a known genome sequence for studying developmental seeds. In the study, the seeds of 10th day after flowering (DAF) were conducted RNA-Seq of the variety Shindongjin and Sugary mutant using RNA-seq technique. Approximately 202 and 214 million high-quality paired-end reads (101-bp in size) were generated in Shindongjin and Sugary mutant, respectively. Comprehensive analysis on the transcript levels of genes which encode starch-synthesis enzymes is fundamental for the assessment of the function of each enzyme and the regulatory mechanism of starch biosynthesis in seeds. Quantitative real-time PCR was also used to validate the expression profiles of 28 rice genes encoding six classes of enzymes, viz., ADPglucose pyrophosphorylase (AGPase), starch synthase, starch branching enzyme, starch debranching enzyme, starch phosphorylase, and disproportionating enzyme at different developmental grain- filling stages (DAF 1-14) between Shindongjin and Sugary mutant. The results showed that the expression of most of starch synthesis genes were up-regulated except the cytosolic AGPase small subunit2b (AGPS2b), which sharply decreased at grain-filling stages in Sugary mutant. These results will expand our understanding of the complex molecular and cellular events in rice grain-filling stages and provide a fundamental understanding of future studies on developmental endosperm in rice and other cereal crops.

Security Threats among DICOM Imaging Communications in Public Networks

Feng Zhou,Zhongqi Zhang,Jin Wang,Bin Li,Jeong-Uk Kim 보안공학연구지원센터 2014 International Journal of Future Generation Communi Vol.7 No.6

Picture archiving and communication systems (PACS) require high-speed networks to transmit large image files between components. Image-data transmission from one site to another through public network is usually characterized in term of privacy, authenticity, and integrity. However, public network’s security issues had always been the significant problems. Recent years, IPv6 brings significant improvements in mechanisms for assuring a higher level of security and confidentiality of the transmitted information. Thus, it is still necessary to take care of some particular aspects. In this paper, we first analyzes how actual security threats and different types of attacks affect IPv6 networks while transmitting Digital Imaging and Communications in Medicine (DICOM) files through the public Internet. Second, illustrate some shortcomings of IPv6 and IPv6’s traffic loads. Finally, some possible solutions against a number of security threats in IPv6 DICOM files transmitting networks have been given.