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>

석탄바닥재로 제조된 결정화 유리의 물리적 특성에 미치는 Li₂O 첨가 영향

엄누리,강승구,Um, Noo-Li,Kang, Seung-Gu 한국재료학회 2010 한국재료학회지 Vol.20 No.2

Glass-ceramics were fabricated by heat-treatment of glass obtained by melting a coal bottom ash with $Li_2O$ addition. The main crystal grown in the glass-ceramics, containing 10 wt% $Li_2O$, was $\beta$-spodumene solid solution, while in $Li_2O$ 20 wt% specimen was mullite, identified using XRD. The activation energy and Avrami constant for crystallization were calculated and showed that bulk crystallization behavior will be predominant, and this expectation agreed with the microstructural observations. The crystal phase grown in $Li_2O$ 10 wt% glass-ceramics had a dendrite-like shaped whereas the shape was flake-like in the 20 wt% case. The thermal expansion coefficient of the $Li_2O$ 10 wt% glass-ceramics was lower than that of the glass having the same composition, owing to the formation of a $\beta$-spodumene phase. For example, the thermal expansion coefficient of $Li_2O$ 10 wt% glass-ceramics was $20\times10^{-7}$, which is enough for application in various heat-resistance fields. But above 20 wt% $Li_2O$, the thermal coefficient expansion of glass-ceramics, on the contrary, was higher than that of the same composition glass, due to formation of mullite.

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>

An extremely thermostable maltogenic amylase from <i>Staphylothermus marinus</i>: <i>Bacillus</i> expression of the gene and its application in genistin glycosylation

Li, Xiaolei,Wang, Yujuan,Park, Jong-Tae,Gu, Liwei,Li, Dan Elsevier 2018 INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES Vol.107 No.1

<P><B>Abstract</B></P> <P>The most extremely thermostable maltogenic amylase (SMMA) from archaeon <I>Staphylothermus marinus</I> has many potential applications in food processing. To ensure safety of microbial origin, a recombinant plasmid containing the enzymic gene and a constitutive promoter AmyR2 was constructed, and then transformed into a GRAS microorganism <I>Bacillus subtilis</I>. The purified SMMA from the liquid cultures of <I>Bacillus</I> has a specific activity of 66.96U/mg, two times more than that from <I>Escherichia coli</I>. SMMA was further employed to catalyze the genistion glycosylation using γ-CD as both glucosyl donors and solubilizer. Glycosylated genistins with one to four additional α-glucosyls and a molar percentage of 69.87% in genistin reaction mixture were identified and quantified by HPLC–UV–MS. The glycosylated genistins at 0.2–1.2mM showed an enhanced DPPH free radical scavenging capacity. To our knowledge, this is the first report on the <I>Bacillus</I> expression of archaeal maltogenic amylase.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A fused gene of SMMA and a constitutive promoter AmyR2 was transformed into <I>B. subtilis</I>. </LI> <LI> Specific activity of purified SMMA from <I>B. subtilis</I> was two times more than that from <I>E. coli</I>. </LI> <LI> SMMA of safe microbial origin attached different number of glucosyls from γ-CD to genistin at 90°C. </LI> <LI> Glycosylated genistins showed an enhanced DPPH free radical scavenging capacity than genistin. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Electronic structure and optical properties of V-doped Bi₄Ti₃O₁₂ nanoparticles

Gu, Daguo,Qin, Yingying,Wen, Yongchun,Li, Tie,Qin, Lin,Seo, Hyo Jin Elsevier 2017 Journal of Alloys and Compounds Vol.695 No.-

<P><B>Abstract</B></P> <P>Pure and V<SUP>5+</SUP>-doped Bi<SUB>4</SUB>Ti<SUB>3</SUB>O<SUB>12</SUB> (BTO) photocatalysts were prepared by sol–gel routine and subsequent hydrothermal synthesis. The samples were developed into the platelike microparticles with the exposed (001) facets. The crystalline phases were verified via the XRD measurement. The surface characteristics of the photocatalysts were studied by TEM, SEM, BET, EDX and XPS measurements. The UV–vis optical absorption spectra showed that the V-doped photocatalysts exhibit an obvious red shift in the visible light absorption band compared with the pure BTO. Rhodamine B (RhB) dye solution was used as the model organic pollutants to verify the influence of V-doping on the photocatalytic activity. The 10 mol % V-doped BTO showed efficient photocatalytic ability. The photocatalytic activities and mechanisms were discussed on the crystal structure characteristics and the measurements such as EES and XPS results.</P> <P><B>Highlights</B></P> <P> <UL> <LI> V-doped Bi<SUB>4</SUB>Ti<SUB>3</SUB>O<SUB>12</SUB> has been synthesized by sol-gel hydrothermal process. </LI> <LI> Single-crystal micro-plates with exposed {001} facets are reached. </LI> <LI> Visible light absorption in Bi<SUB>4</SUB>Ti<SUB>3</SUB>O<SUB>12</SUB> can be greatly improved by V-doping. </LI> <LI> V-doped Bi<SUB>4</SUB>Ti<SUB>3</SUB>O<SUB>12</SUB> gives better visible light photoactivity. </LI> </UL> </P>

《文选》及李善注所涉神话的数据统计与分析

李立(Li Li),?月(Gu Yue),李炫周(Li Xuan-zhou) 한국중어중문학회 2009 中語中文學 Vol.45 No.-

In the present study of anthology, even few scholars have been studying the myth involved in Wen Xuan and its annotated version. The results of the studies are still rare, There are over 140 workers poetries with mythological images in over 700 works which included in Wen Xuan, it was 20% of the total. And the above-mentioned 140 poetries, most of which are annotated by Li Shan, richly embellished with quotations and allusions to classical mythology in poems. The Cbu Ci that has been most frequently quoted it, secondarily Shan Hai Jing, thirdly Huai Nan Zi. Zhuang Zi has come in the fourth. A "Book of Myth" in Wen Xuan, which annotated by Li Shan, mentioned case of myth, and The Chu Ci, Shan Hai Jing and Huai Nan Zi from which over 10 types of myth were quoted, just Shan Hai Jing instead of The Chu Ci had held the first position. Of the 48 kinds of myths in the Wen Xuan by Li Shan annotated, "natural myth was the most, followed by the social myth", then "goddess myth", "creation myth" at least, with only three kinds. Most work s of Wen Xuan were recorded in Two Han Wei Jin Southern and Northern Dynasties, most poems with mythological images were also recorded in the same period. According to the above analysis. Two Han Wei Jin Southern and Northern Dynasties, was not only an important period that Chinese ancient myth was developed evolved, but also an important period that mythology and ancient literature linked by a close relationship.

<i>Prorocentrum shikokuense</i> Hada and <i>P. donghaiense</i> Lu are junior synonyms of <i>P. obtusidens</i> Schiller, but not of <i>P. dentatum</i> Stein (Prorocentrales, Dinophyceae)

Shin, Hyeon Ho,Li, Zhun,Mertens, Kenneth Neil,Seo, Min Ho,Gu, Haifeng,Lim, Weol Ae,Yoon, Yang Ho,Soh, Ho Young,Matsuoka, Kazumi Elsevier 2019 Harmful algae Vol.89 No.-

<P><B>Abstract</B></P> <P>In Japanese, Chinese and Korean coastal waters, recurrent blooms of a small, elongate <I>Prorocentrum</I> species have been observed in recent years. In previous studies, this species has been respectively identified as <I>P. shikokuense</I>, <I>P. donghaiense</I> and <I>P. dentatum</I>, despite morphological similarity and identical rDNA sequences. To resolve the confusion, morphological features, including the architectural details of the periflagellar area, were examined and ribosomal DNA (rDNA) sequences were obtained from specimens collected from the East China Sea and Korean coast, and a strain established in the waters off the Canary Islands of Spain. In addition, the descriptions of the three species and allied species were reviewed. Morphological observations and a phylogeny based on the SSU, ITS region and LSU rDNA sequences revealed that the previously confused species and our studied strains are conspecific and that the morphology of strains identified as <I>P. dentatum</I> in the phylogenetic trees does not coincide with <I>P. dentatum sensu stricto</I>. The confusion can be traced back to Dodge (1975, p. 116), who considered <I>P. veloi, P. monacense</I> and <I>P. obtusidens</I> as junior heterotypic synonyms of <I>P. dentatum</I>. However, Dodge’s <I>P. dentatum</I> are closer to <I>P. obtusidens sensu stricto</I>, rather than <I>P. dentatum sensu stricto</I>. <I>P. obtusidens sensu stricto</I> can be distinguished from <I>P. dentatum sensu stricto</I> by its relatively small size, parallel sides towards the anterior and a blunt anterior extension on one side. This indicates that <I>P. obtusidens</I> should not be considered a synonym of <I>P. dentatum sensu stricto</I>. In addition, a comparison of the original descriptions of <I>P. obtusidens</I> and allied species allowed to conclude that small, elongate <I>Prorocentrum</I> from Japanese, Chinese and Korean coastal waters previously identified as <I>P. shikokuense</I>, <I>P. donghaiense</I>, <I>P. dentatum sensu</I> Yoo and Lee (1986) and the specimens studied herein, which share identical rDNA sequences, morphologically coincide with <I>P. obtusidens.</I> Therefore, it is proposed that <I>P. shikokuense</I> and <I>P. donghaiense</I> should be regarded as junior synonyms of <I>P. obtusidens.</I> </P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Prorocentrum shikokuense</I> Hada, <I>P. donghaiense</I> Lu and <I>Prorocentrum obtusidens</I> Schiller are conspecific. </LI> <LI> <I>Prorocentrum obtusidens</I> is a senior to <I>P. shikokuense</I> and <I>P. donghaiense</I>. </LI> <LI> <I>Prorocentrum obtusidens</I> is a separate species from <I>P. dentatum sensu stricto</I>, <I>P. veloi</I> and <I>P. monacense</I>. </LI> <LI> The periflagellar area of <I>Prorocentrum obtusidens</I> consists of seven platelets bearing a wing-like structure and two platelets without a wing-like structure, one flagellar pore and one accessory pore. </LI> </UL> </P>

Oxymatrine Causes Hepatotoxicity by Promoting the Phosphorylation of JNK and Induction of Endoplasmic Reticulum Stress Mediated by ROS in LO2 Cells

Gu, Li-li,Shen, Zhe-lun,Li, Yang-Lei,Bao, Yi-Qi,Lu, Hong Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.5

Oxymatrine (OMT) often used in treatment for chronic hepatitis B virus infection in clinic. However, OMT-induced liver injury has been reported. In this study, we aim to investigate the possible mechanism of OMT-induced hepatotoxicity in human normal liver cells (L02). Exposed cells to OMT, the cell viability was decreased and apoptosis rate increased, the intracellular markers of oxidative stress were changed. Simultaneously, OMT altered apoptotic related proteins levels, including Bcl-2, Bax and pro-caspase-8/-9/-3. In addition, OMT enhanced the protein levels of endoplasmic reticulum (ER) stress makers (GRP78/Bip, CHOP, and cleaved-Caspase-4) and phosphorylation of c-Jun N-terminal kinase (p-JNK), as well as the mRNA levels of GRP78/Bip, CHOP, caspase-4, and ER stress sensors (IREI, ATF6, and PERK). Pre-treatment with Z-VAD-fmk, JNK inhibitor SP600125 and N-acetyl-l-cysteine (NAC), a ROS scavenger, partly improved the survival rates and restored OMT-induced cellular damage, and reduced caspase-3 cleavage. SP600125 or NAC reduced OMT-induced p-JNK and NAC significantly lowered caspase-4. Furthermore, 4-PBA, the ER stress inhibitor, weakened inhibitory effect of OMT on cells, on the contrary, TM worsen. 4-PBA also reduced the levels of p-JNK and cleaved-caspase-3 proteins. Therefore, OMT-induced injury in L02 cells was related to ROS mediated p-JNK and ER stress induction. Antioxidant, by inhibition of p-JNK or ER stress, may be a feasible method to alleviate OMT-induced liver injury.

An Improved K-means Algorithm based on Mapreduce and Grid

Li Ma,Lei Gu,Bo Li,Yue Ma,Jin Wang 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

The traditional K-means clustering algorithm is difficult to initialize the number of clusters K, and the initial cluster centers are selected randomly, this makes the clustering results very unstable. Meanwhile, algorithms are susceptible to noise points. To solve the problems, the traditional K-means algorithm is improved. The improved method is divided into the same grid in space, according to the size of the data point property value and assigns it to the corresponding grid. And count the number of data points in each grid. Selecting M(M>K) grids, comprising the maximum number of data points, and calculate the central point. These M central points as input data, and then to determine the k value based on the clustering results. In the M points, find K points farthest from each other and those K center points as the initial cluster center of K-means clustering algorithm. At the same time, the maximum value in M must be included in K. If the number of data in the grid less than the threshold, then these points will be considered as noise points and be removed. In order to make the improved algorithm can adapt to handle large data. We will parallel the improved k-mean algorithm and combined with the MapReduce framework. Theoretical analysis and experimental results show that the improved algorithm compared to the traditional K-means clustering algorithm has high quality results, less iteration and has good stability. Parallelized algorithm has a very high efficiency in data processing, and has good scalability and speedup.

Oxymatrine Causes Hepatotoxicity by Promoting the Phosphorylation of JNK and Induction of Endoplasmic Reticulum Stress Mediated by ROS in LO2 Cells

Li-li Gu,Zhe-lun Shen,Yang-Lei Li,Yi-Qi Bao,Hong Lu 한국분자세포생물학회 2018 Molecules and cells Vol.41 No.5

Oxymatrine (OMT) often used in treatment for chronic hepatitis B virus infection in clinic. However, OMT–induced liver injury has been reported. In this study, we aim to investigate the possible mechanism of OMT-induced hepatotoxicity in human normal liver cells (L02). Exposed cells to OMT, the cell viability was decreased and apoptosis rate increased, the intracellular markers of oxidative stress were changed. Simultaneously, OMT altered apoptotic related proteins levels, including Bcl-2, Bax and pro-caspase-8/-9/-3. In addition, OMT enhanced the protein levels of endoplasmic reticulum (ER) stress makers (GRP78/Bip, CHOP, and cleaved-Caspase-4) and phosphorylation of c-Jun N-terminal kinase (p-JNK), as well as the mRNA levels of GRP78/Bip, CHOP, caspase-4, and ER stress sensors (IREI, ATF6, and PERK). Pre-treatment with Z-VAD-fmk, JNK inhibitor SP600125 and N-acetyl-l-cysteine (NAC), a ROS scavenger, partly improved the survival rates and restored OMT-induced cellular damage, and reduced caspase-3 cleavage. SP600125 or NAC reduced OMT-induced p-JNK and NAC significantly lowered caspase-4. Furthermore, 4-PBA, the ER stress inhibitor, weakened inhibitory effect of OMT on cells, on the contrary, TM worsen. 4-PBA also reduced the levels of p-JNK and cleaved-caspase-3 proteins. Therefore, OMT-induced injury in L02 cells was related to ROS mediated p-JNK and ER stress induction. Antioxidant, by inhibition of p-JNK or ER stress, may be a feasible method to alleviate OMT-induced liver injury.