Nanostructured carbon-based cathode catalysts for nonaqueous lithium–oxygen batteries

Li, Qing,Cao, Ruiguo,Cho, Jaephil,Wu, Gang The Royal Society of Chemistry 2014 Physical chemistry chemical physics Vol.16 No.27

<P>Although lithium-ion batteries are traditionally considered to be the most promising candidate for electrochemical energy storage owing to their relatively long cycle life and high energy efficiency, their limited energy density as well as high cost are still causing a bottleneck for their long-term applications. Alternatively, rechargeable Li–O<SUB>2</SUB> batteries have the potential to practically provide 3–5 times the gravimetric energy density of conventional Li-ion batteries. However, the lack of advanced electrode design and efficient electrocatalysts for oxygen reduction–evolution reactions remains as one of the grand challenges before this technology can be commercialized. Among various catalyst formulations, nanocarbon composite materials have been recognized as the most promising ones for Li–O<SUB>2</SUB> batteries because of their reasonable balance among catalytic activity, durability, and cost. In this perspective, the recent progress in the development of nanostructured carbon-based electrocatalysts for nonaqueous Li–O<SUB>2</SUB> batteries is discussed, including metal-free carbon catalysts, transition-metal–nitrogen–carbon composite catalysts, and transition-metal-compounds/nanocarbon catalysts. The morphology–performance correlations of these catalysts are highlighted, aiming to provide guidance for rationally designing advanced catalysts.</P> <P>Graphic Abstract</P><P>Structure–activity correlations of nanocarbon oxygen cathode catalysts for nonaqueous Li–O<SUB>2</SUB> batteries are discussed, providing guidance for rational catalyst design. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4cp00225c'> </P>

Characteristics of isolated lactic acid bacteria and their effects on the silage quality

Siran Wang,Xianjun Yuan,Zhihao Dong,Junfeng Li,Gang Guo,Yunfeng Bai,Junyu Zhang,Tao Shao 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.6

Objective: Four lactic acid bacteria (LAB) strains isolated from common vetch, tall fescue and perennial ryegrass on the Tibetan Plateau were characterized, and their effects on the fermentation quality of Italian ryegrass (Lolium multiflorum Lam.) silage were studied. Methods: The four isolated strains and one commercial inoculant (G, Lactobacillus plantarum MTD-1) were evaluated using the acid production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. The five LAB strains were added to Italian ryegrass for ensiling at three different temperatures (10°C, 15°C, and 25°C). Results: All isolated strains (LCG3, LTG7, I5, and LI3) could grow at 5°C to 20°C, pH 3.0 to 8.0 and NaCl (3.0%, 6.5%). Strains LCG3, LTG7, I5, and LI3 were identified as Lactobacillus plantarum, Pediococcus acidilactici, Lactobacillus paraplantarum, and Lactobacillus casei by sequencing 16S rDNA, respectively. All LAB inoculants significantly (p<0.05) increased lactic acid (LA) contents and ratios of lactic acid to acetic acid, and reduced pH and ammonia nitrogen/ total nitrogen (AN/TN) compared with uninoculated silages at various temperatures (10°C, 15°C, and 25°C). Compared to the commercial inoculant G, I5, and LI3 showed similar effects on improving the silage quality of Italian ryegrass at 10°C and 15°C, indicated by similar pH, LA content and AN/TN. Conclusion: All inoculants could improve the silage fermentation quality at various temperatures (10°C, 15°C, and 25°C). At the temperature of 10°C and 15°C, strain I5 and LI3 had similar effects with the commercial inoculant G on improving the silage quality of Italian ryegrass.

Dislocation Density-Based Constitutive Model and Processing Map for T2 Copper During Isothermal and Time-Variant Deformation

Gang Chen,Yu Jin,Jing Wang,Cheng Zhang,Qiang Chen,Hongming Zhang,Xingjian Zhao,Zhiyong Li,Changhai Xie,Zhiming Du 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9

Isothermal compression tests were carried out to study the hot deformation behavior of T2 copper under various conditions. The deformation parameters, such as temperature and strain rate, have strong influence on flow stress and microstructureevolution of the alloy. A unified dislocation density-based model considering dynamic recovery and recrystallization wasestablished. And material parameters of the developed model were optimized by genetic algorithm. Comparisons betweenthe experimental and model data demonstrates that the developed model can precisely describe the flow behavior at quitewide range of deformation conditions. Meanwhile, the designed iterative procedure allows the model to be applied in timevariantdeformation conditions. Processing map and microstructure examination were constructed to optimize the processingwindow of the studied alloy. According to the processing maps, flow instability mainly appeared at low temperatures of500–650 °C and strain rates higher than 0.1 s−1. The optimum deformation parameters of T2 copper was concluded as thetemperature range of 700–800 °C and the strain rate of 0.1–1 s−1.

철근 이음형 PC 보-기둥 내부 접합부의 구조적 거동에 관한 실험적 연구

김승훈,하상수,문정호,이리형,이강철,전병갑 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

In this study, new moment-resisting precast concrete beam-column joint is proposed for moderate seismic regions. It has the connection reinforcing bars, penetrated the joint and lap-spliced with the bottom bars of precast U-beam. An experimental study was carried out to investigate the joint behavior subjected to reverse cyclic loading and constant axial compressive load. Three precast beam-column interior were tested. The variables examined were the type of connection reinforcing bars and presence of transverse reinforcement in joint. Joint performance is evaluated on the basis of connection .strength, stiffness, energy dissipation, and drift capacity. Based on the test results, the precast connection is capable of matching or exceeding the performance of the monolithic connection and thereby provides the sufficient moment-resisting behavior to be applicable for moderate seismic regions.

Modeling urban building energy use: A review of modeling approaches and procedures

Li, Wenliang,Zhou, Yuyu,Cetin, Kristen,Eom, Jiyong,Wang, Yu,Chen, Gang,Zhang, Xuesong Elsevier 2017 ENERGY Vol.141 No.-

<P><B>Abstract</B></P> <P>With rapid urbanization and economic development, the world has been experiencing an unprecedented increase in energy consumption and greenhouse gas (GHG) emissions. While reducing energy consumption and GHG emissions is a common interest shared by major developed and developing countries, actions to enable these global reductions are generally implemented at the city scale. This is because baseline information from individual cities plays an important role in identifying economical options for improving building energy efficiency and reducing GHG emissions. Numerous approaches have been proposed for modeling urban building energy use in the past decades. This paper aims to provide an up-to-date review of the broad categories of energy models for urban buildings and describes the basic workflow of physics-based, bottom-up models and their applications in simulating urban-scale building energy use. Because there are significant differences across models with varied potential for application, strengths and weaknesses of the reviewed models are also presented. This is followed by a discussion of challenging issues associated with model preparation and calibration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Advances in urban buildings energy models are reviewed. </LI> <LI> Strengths and weaknesses of urban building energy models are discussed. </LI> <LI> The workflow of physics-based bottom-up models are illuminated. </LI> <LI> Challenges and future research avenues in urban buildings energy use modeling are highlighted. </LI> </UL> </P>

Gyral net: A new representation of cortical folding organization

Chen, Hanbo,Li, Yujie,Ge, Fangfei,Li, Gang,Shen, Dinggang,Liu, Tianming Elsevier 2017 Medical image analysis Vol.42 No.-

<P><B>Abstract</B></P> <P>One distinct feature of the cerebral cortex is its convex (gyri) and concave (sulci) folding patterns. Due to the remarkable complexity and variability of gyral/sulcal shapes, it has been challenging to quantitatively model their organization patterns. Inspired by the observation that the lines of gyral crests can form a connected graph on each brain hemisphere, we propose a new representation of cortical gyri/sulci organization pattern – gyral net, which models cortical architecture from a graph perspective, starting with nodes and edges obtained from the reconstructed cortical surfaces. A novel computational framework is developed to efficiently and automatically construct gyral nets from surface meshes, and four measurements are devised to quantify the folding patterns. Using an MRI dataset for autism study as a test bed, we identified reduced local connectivity cost and increased curviness of gyral net bilaterally on the parietal lobe, occipital lobe, and temporal lobe in autistic patients. Additionally, we found that the cortical thickness and the gyral straightness of gyral joints are higher than the rest of gyral crest regions. The proposed representation offers a new tool for a comprehensive and reliable characterization of the cortical folding organization. This novel computational framework will enable large-scale analyses of cortical folding patterns in the future.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new representation of cortical gyri/sulci organization pattern. </LI> <LI> A novel framework to efficiently and automatically construct gyral net from mesh surface. </LI> <LI> A new tool for a comprehensive and reliable characterization of the cortical folding organization. </LI> <LI> Enable large-scale cortical folding pattern analyses in the future. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Illustration of the concept of gyral net and gyral joint. (a) Reconstructed cortical surface color-coded by gyral altitude. (b) Extracted gyral net. (c) Zoom in view of the circled area in (b). In this paper, we propose a new representation of cortical gyri/sulci organization pattern – gyral net, which models cortical architecture from a graph perspective, starting with nodes and edges obtained from the surface reconstructions.</P> <P>[DISPLAY OMISSION]</P>

Red, green, and blue fluorescent folate-receptor-targeting carbon dots for cervical cancer cellular and tissue imaging

Li, Shihao,Jiang, Jie,Yan, Yinan,Wang, Ping,Huang, Gang,Kim, Nam hoon,Lee, Joong Hee,He, Dannong Elsevier 2018 Materials science & engineering. C, Materials for Vol.93 No.-

<P><B>Abstract</B></P> <P>Folate receptor targeted photo-luminescent quantum carbon dots (Fr-CDs) were successfully prepared from folic acid and phenylenediamine isomers through hydrothermal approaches. Fr-CDs were spherical particles smaller than 10 nm, and emit stable green, blue and red luminescence under ultraviolet region excitation (λex = 365 nm) with maximum emissive lengths at 530, 429, and 612 nm. And the corresponding photoluminescence quantum yield as 15.4%, 12.6% and 16.2% respectively. Up-converted photoluminescent properties in near infrared 800 nm spectral region located in green, blue and yellow region. In-vitro studies showed Fr-CDs had almost none cytotoxicity (cell viability over 80%) and high affinitive to the Hela celline highly-expressed-folate-receptor membranes, and lighted on cytoplasm as the fluorescent marker. It displayed long luminescent-stability with PL intensity above 90% in ultraviolet illuminant exposure over 24 h. In in-vivo studies, Fr-CDs were internalized and accumulated in targeted cancer tissues of cervical carcinoma and the emitting fluorescence maintains over 30 min.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Multicolor carbon dots was prepared from folic acid and phenylenediamin isomers. </LI> <LI> These carbon dots exhibit targeting abilities with high affinity to ovarian cancer cells and tissues. </LI> <LI> Ultra-violet and near-infrared light excited photo-luminescent spectrums were investigated, and related quantum yield was calculated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>FA-doped CDs can effectively target ovarian cancer cells and aggregate in ovarian tumor tissue in a short 15 min.</P> <P>[DISPLAY OMISSION]</P>

miR-98 suppresses melanoma metastasis through a negative feedback loop with its target gene IL-6

Fei Li,Xin-ji Li,Li Qiao,Fei Shi,Wen Liu,You Li,Yu-ping Dang,Weijie Gu,Xiao-gang Wang,Wei Liu 생화학분자생물학회 2014 Experimental and molecular medicine Vol.46 No.-

Dysregulated microRNA (miRNA) expression has a critical role in tumor development and metastasis. However, the mechanism by which miRNAs control melanoma metastasis is unknown. Here, we report reduced miR-98 expression in melanoma tissues with increasing tumor stage as well as metastasis; its expression is also negatively associated with melanoma patient survival. Furthermore, we demonstrate that miR-98 inhibits melanoma cell migration in vitro as well as metastatic tumor size in vivo. We also found that IL-6 is a target gene of miR-98, and IL-6 represses miR-98 levels via the Stat3-NF-κB-lin28B pathway. In an in vivo melanoma model, we demonstrate that miR-98 reduces melanoma metastasis and increases survival in part by reducing IL-6 levels; it also decreases Stat3 and p65 phosphorylation as well as lin28B mRNA levels. These results suggest that miR-98 inhibits melanoma metastasis in part through a novel miR-98-IL-6-negative feedback loop.

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.

Mixtures of Tea and Citrus maxima (pomelo) Alleviate Lipid Deposition in HepG2 Cells Through the AMPK/ACC Signaling Pathway

Ran An,Shuai Wen,Dong-Li Li,Qiu-Hua Li,Xing-Fei Lai,Wen-Ji Zhang,Ruo-Hong Chen,Jun-Xi Cao,Zhi-Gang Li,Qiu-Sheng Huang,Ling-Li Sun,Shi-Li Sun 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.9

Tea and citrus maxima are natural, medicinal homologous plants, typically used for making beverages, which have anticancer, antiobesity, and antioxidation properties. Green tea, yellow tea, and black tea were combined with citrus maxima to obtain green tea and Citrus maxima (GTCM), yellow tea and Citrus maxima (YTCM), and black tea and Citrus maxima (BTCM). The biochemical components of these mixtures were analyzed, and their possible effects and mechanisms on relieving liver lipid deposition were explored. The tea polyphenols, free amino acids, phenolamine ratio, and caffeine were comparable in YTCM and GTCM, being significantly higher than those in BTCM. In addition, the content of esterified catechins, nonesterified catechins, and total catechins in YTCM was significantly higher than those in GTCM and BTCM. All three mixtures of Citrus maxima tea significantly reduced lipid deposition in HepG2 cells, with GTCM and YTCM being slightly more effective than BTCM. Regarding the possible mechanism, Western blot analysis revealed that the three Citrus maxima tea mixtures could activate the AMPK/ACC signaling pathway, upregulate the expression of p-AMPK, p-ACC, and CPT-1 proteins, and downregulate the expression of SREBP1c and fatty acid synthase proteins to inhibit fat synthesis, thereby relieving lipid deposition in liver cells. In conclusion, as a novel and healthy beverage, Citrus maxima tea has the potential to alleviate liver lipid deposition, and further could be responsible for obesity treatment.