A theoretical study on fullerene-dizincocene hybrids

Gao, Guohua,Xu, Xiang,Kang, Hong Seok Wiley Subscription Services, Inc., A Wiley Company 2009 Journal of computational chemistry Vol.30 No.6

<P>Using the density functional theory, we investigated the possible formation of fullerene-dizincocene hybrids, specifically C<SUB>60</SUB>*-Zn-Zn-Cp*, C<SUB>60</SUB>*-Zn-Zn-C<SUB>60</SUB>*, C<SUB>70</SUB>*-Zn-Zn-Cp*, and C<SUB>70</SUB>*-Zn-Zn-C<SUB>70</SUB>*, where C<SUB>60</SUB>*, Cp*, and C<SUB>70</SUB>* represent C<SUB>60</SUB>(CH<SUB>3</SUB>)<SUB>5</SUB>, C<SUB>5</SUB>(CH<SUB>3</SUB>)<SUB>5</SUB>, and C<SUB>70</SUB>(CH<SUB>3</SUB>)<SUB>5</SUB> radicals. Our calculation shows that these hybrids have HOMO-LUMO gaps which are larger than has been experimentally identified for C<SUB>60</SUB>*-Fe-Cp. In addition, the strength of the Zn&n.bond;Zn bonds is similar to that in Cp*-Zn-Zn-Cp* which was also synthesized recently. Furthermore, heterohybrids, C<SUB>60</SUB>*-Zn-Zn-Cp* and C<SUB>70</SUB>*-Zn-Zn-Cp* are expected to exist in equilibria with homohybrids, C<SUB>60</SUB>*-Zn-Zn-C<SUB>60</SUB>* and C<SUB>70</SUB>*-Zn-Zn-C<SUB>70</SUB>*, in which heterohybrids are much more favored. On the other hand, another hybrid involving Sc<SUB>3</SUB>N@C<SUB>68</SUB> as a fullerene unit is not highly probable. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009</P> <B>Graphic Abstract</B> <P> <img src='wiley_img/01928651-2009-30-6-JCC21121-gra001.gif' alt='wiley_img/01928651-2009-30-6-JCC21121-gra001'> </P>

rGO/VNTs as cathodes for high performance sodium ion batteries with good cycling performance

Guohua Gao,Mingze Ji,Kun Zhang,Guangming Wu 대한금속·재료학회 2022 ELECTRONIC MATERIALS LETTERS Vol.18 No.1

Using the ex-situ composite method, we have prepared grapheme coating vanadium oxide nanotubes (VNT) by using vanadium oxide nanotubes, cationic surfactant cetyltrimethylammonium bromide (CTAB) and graphene oxide (GO) aqueous solution. The surface of the vanadium oxide nanotube was modified by CTAB, so that vanadium oxide nanotubes were combined with graphene oxide via electrostatic interaction. The introduction of graphene provides an effective protective layer for vanadium oxide nanotubes, alleviates the volume change caused by sodium ion insertion and extraction during charge and discharge process, and enhances the stability of vanadium oxide nanotube structure. The electrochemical test show that the capacity retention of VNTs after 50 cycles was only 18%, while the capacity retention rate of VNTs/rGO was as high as 74%. In addition, we made a detailed analysis of the morphology, structure and formation mechanism of the materials.

Uncertainty analysis of containment dose rate for core damage assessment in nuclear power plants

Guohua Wu,Jiejuan Tong,Yan Gao,Liguo Zhang,Yunfei Zhao 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.5

One of the most widely used methods to estimate core damage during a nuclear power plant accident iscontainment radiation measurement. The evolution of severe accidents is extremely complex, leading touncertainty in the containment dose rate (CDR). Therefore, it is difficult to accurately determine coredamage. This study proposes to conduct uncertainty analysis of CDR for core damage assessment. First,based on source term estimation, the Monte Carlo (MC) and point-kernel integration methods were usedto estimate the probability density function of the CDR under different extents of core damage in accidentscenarios with late containment failure. Second, the results were verified by comparing the resultsof both methods. The point-kernel integration method results were more dispersed than the MC results,and the MC method was used for both quantitative and qualitative analyses. Quantitative analysisindicated a linear relationship, rather than the expected proportional relationship, between the CDR andcore damage fraction. The CDR distribution obeyed a logarithmic normal distribution in accidents with asmall break in containment, but not in accidents with a large break in containment. A possible applicationof our analysis is a real-time core damage estimation program based on the CDR

Electrospun Porcine Acellular Dermal Matrix and Polycaprolactone Composite Nanofibrous Scaffolds for Accelerating Wound Healing

Xiaofei Gao,Guohua Jiang,Liming Ruan,Yanfang Sun,Khaydar E. Yunusov,Yanting Jing,Uladzislau E. Aharodnikau,Sergey O. Solomevich 한국섬유공학회 2023 Fibers and polymers Vol.24 No.2

Electrospun nanofibers represent a novel class of scaffold materials that show great potential in wound healing owing torelatively large surface area, better mimicry of native extracellular matrix, adjustable waterproofness and breathability, andprogrammable drug delivery process. In this work, electrospun polycaprolactone (PCL) and porcine acellular dermal matrix(PADM) composite nanofibrous membranes have been developed by electrospinning technology and inflated into threedimensional(3D) structural scaffold (PCL-PADM) by gas foaming method. The obtained PCL-PADM has higher thermalstability, hydrophilicity and better cell adhesion compared with PCL. In addition, ε-polylysine (ε-PL) is further attachedonto the surface of PADM/PCL to offer its good antibacterial properties. Moreover, the PADM/PCL fibrous scaffolds showexcellent cytocompatibility for promoting cell proliferation. In vivo models showed that the resultant PADM/PCL fibrousscaffolds exhibit an accelerating wound healing effect through promoting expression of vascular factor (CD31) and decreasingthe expression of tumor necrosis factor-α (TNF-α). These results indicate that the 3D fibrous scaffolds may be a potentialwound dressing for wound closure.

Transcriptome-wide characterization of the WRKY family genes in Lonicera macranthoides and the role of LmWRKY16 in plant senescence

Cao Zhengyan,Wu Peiyin,Gao Hongmei,Xia Ning,Jiang Ying,Tang Ning,Liu Guohua,Chen Zexiong 한국유전학회 2022 Genes & Genomics Vol.44 No.2

Background: Lonicera macranthoides is an important woody plant with high medicinal values widely cultivated in southern China. WRKY, one of the largest transcription factor families, participates in plant development, senescence, and stress responses. However, a comprehensive study of the WRKY family in L. macranthoides hasn't been reported previously. Objective: To establish an extensive overview of the WRKY family in L. macranthoides and identify senescence-responsive members of LmWRKYs. Methods: RNA-Seq and phylogenetic analysis were employed to identify the LmWRKYs and their evolutionary relationships. Quantitative real-time (qRT-PCR) and transgenic technology was utilized to investigate the roles of LmWRKYs in response to developmental-, cold-, and ethylene-induced senescence. Results: A total of 61 LmWRKY genes with a highly conserved motif WRKYGQK were identified. Phylogenetic analysis of LmWRKYs together with their orthologs from Arabidopsis classified them into three groups, with the number of 15, 39, and 7, respectively. 17 LmWRKYs were identified to be differentially expressed between young and aging leaves by RNA-Seq. Further qRT-PCR analysis showed 15 and 5 LmWRKY genes were significantly induced responding to tissue senescence in leaves and stems, respectively. What's more, five LmWRKYs, including LmWRKY4, LmWRKY5, LmWRKY6, LmWRKY11, and LmWRKY16 were dramatically upregulated under cold and ethylene treatment in both leaves and stems, indicating their involvements commonly in developmental- and stress-induced senescence. In addition, function analysis revealed LmWRKY16, a homolog of AtWRKY75, can accelerate plant senescence, as evidenced by leaf yellowing during reproductive growth in LmWRKY16-overexpressing tobaccos. Conclusion: The results lay the foundation for molecular characterization of LmWRKYs in plant senescence.

Functionalized moso bamboo powder adsorbent for Cd(II) complexes with citric acid/tartrate acid: characterization, adsorptive performance, and mechanism

Qinju Sun,Shaohua Lin,Guohua Liu,Yue Xuan,Liping Gao,Pingping Li 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.5

A new amine group functionalized moso bamboo powder adsorbent (AMBP) was prepared using a facile procedure to remove Cd(II) complexes with citric acid (CA) and tartrate acid (TA). The properties of the AMBP were characterized using SEM, FTIR, XPS, BET, and an elemental analysis. The adsorptive performances of the AMBP toward Cd(II)-CA/TA were investigated. The results indicated that amine group was successfully introduced, and the AMBP with a BET specific surface area of 0.463 ㎡/g was effective in adsorbing Cd(II)-CA/TA under pH 4.0–10.0. The removal of Cd(II) increased significantly when the Cd(II)/ligand molar ratio changed from 1:0.5 to 1:2. The adsorption processes of Cd(II)-CA/TA were endothermic and fit well with the pseudo-second-order kinetic model (R² > 0.999). The Langmuir model (qmax of 14.41 and 7.58 mg/g for Cd(II)-CA and Cd(II)-TA, respectively) fit the isotherms better than the Freundlich model. The AMBP could be regenerated by HCl and reused at least 4 times. The uptake mechanisms of Cd(II)-CA/TA were proposed to be physisorption and the chemisorption of the coordination between –NH₂/–NH and the Cd(II). This work shows that the AMBP is an adsorbent with high practical value to remove Cd(II) in water or wastewater containing CA/TA.

Dynamic analysis of a flexure-based compliant stage

Yunsong Du,Tie-Min Li,Guohua Gao 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.11

This paper presents the dynamic analysis of a flexure-based compliant stage. The dynamic model is first obtained, after which the equivalent masses of the flexure hinge, including the axial equivalent mass, the bending equivalent mass, and the shear equivalent mass, are derived. According to this method, the equivalent mass components of the proposed stage are derived by accumulating those of the output platform, input platform, and flexure hinges. Finally, to verify the validity of the proposed method, the first two resonant frequencies and the corresponding mode shapes are analyzed by using finite element analysis (FEA). An experimental platform is fabricated, and experimental results and FEA values appear to be in accordance with the theoretical calculations. This result demonstrates that the dynamic model and equivalent mass are accurate. The dynamic model provides an effective method for calculating equivalent masses, and dynamic characteristics can be precisely estimated from the corresponding analytical models.

An Efficient Dye-Sensitized Solar Cell with an Organic Sensitizer Encapsulated in a Cyclodextrin Cavity

Choi, Hyunbong,Kang, Sang Ook,Ko, Jaejung,Gao, Guohua,Kang, Hong Seok,Kang, Moon-Sung,Nazeeruddin, Md. K.,Grä,tzel, Michael WILEY-VCH Verlag 2009 Angewandte Chemie Vol.48 No.32

<B>Graphic Abstract</B> <P>Dying to get inside: Charge recombination is retarded and dye aggregation is prevented in solar cells that contain the JK-2 dye encapsulated in a cyclodextrin (CD) cavity (see picture). The β-CD/JK-2 device with a polymer gel electrolyte gave an overall conversion efficiency of 7.40 %, which is the highest value reported to date for DSSCs based on the organic sensitizers, and showed excellent stability. <img src='wiley_img/14337851-2009-48-32-ANIE200902013-content.gif' alt='wiley_img/14337851-2009-48-32-ANIE200902013-content'> </P>

Rediscovering Impacts of Collaboration through Workflow Analysis to Value Service Development

Chengxiang Ren,Yucong Duan,Zhangbing Zhou,Guohua Fu,Zhen Guo,Honghao Gao 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.11

Information and service economies are developing rapidly in recent years with the development of information technology and new applications. Software and service development are becoming more and more complex relating to different participants, organizations and alliances. This phenomenon has caused urgent requirements on economic and technical fusion through coordination and collaboration among stakeholders. This paper addresses the gap between business layer and technical development in roles and activities. We then propose a combination of economic value and profits and technical service development processes. We also consider value exchange under profit sharing contracts in participants' workflows. A simulation and an experiment are performed to show related impacts.

평가도구를 이용한 웹 접근성 평가

권영직(Young-Jik Kwon),장굉위(Hongwei Zhang),고국화(Guohua Gao),권동훈(Donghoon Kwon) 한국의사결정학회 2009 의사결정학연구 Vol.17 No.1

모든 사용자가 웹을 통하여 어려움 없이 인터넷에 접근 가능하도록 하기 위해서는, 웹사이트가 웹 접근성을 고려하여 개발되어야 한다. 이러기 위해서 본 논문에서는 웹 접근성 평가 분석도구인 A-Prompt와 KADO-WAH를 사용하여 W3C의 웹 접근성 지침(WCAG 2.0)과 한국형 웹 콘텐츠 접근성 지침(KWCAG 1.0)을 기반으로 5개의 웹 사이트를 대상으로 하여 웹 접근성을 평가한 후, 평가결과를 도출하였다. 본 논문의 연구 결과는 다음과 같다. 첫째, 두 개의 평가도구(KWDO-WAH, A-prompt)로 동일한 체크 항목을 평가한 결과 그 값이 다르게 나왔다. 둘째, 이들 두 개의 평가 도구에 있어서 통일된 평가 지침과 평가항목이 없다. 셋째, 이들 두 개의 평가 도구에 있어서 중복 체크항목은 없어야 하고, 웹 접근성 평가를 위한 필수 항목을 보완해야 한다. A web site should be developed by considering web accessibility for every user. It is due to the fact that every user should access the Internet through the web without any difficulties or challenges. For doing this, this paper derives evaluation results after evaluating web accessibility of five web sites based on WCAG 2.0 of W3c and KWCAG 1.0 by using A-Prompt and KADO-WAH which are called as a analysis tool of web accessibility evaluation. The following is our research results. First, as a result of evaluating same check lists with two evaluation tool (KWDO-WAH, A-Prompt), different value is came out. Second, there are no unified evaluation guide line and evaluation lists about these two evaluation tools. Third, duplicated check lists of these two evaluation tools should be eliminated, and it should come up with necessary lists for evaluating web accessibility.