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Carbon-based derivatives from metal-organic frameworks as cathode hosts for Li–S batteries 被引量:7
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作者 Qingping Wu Xuejun Zhou +2 位作者 Jun Xu Fahai Cao Chilin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期94-113,共20页
Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh... Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed. 展开更多
关键词 Lithium-sulfur BATTERIES Carbon-based derivatives Metal-organic frame works CATHODE host
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Synthesis and Characterization of Novel Mercapto-end Ferrocenyl Derivatives with Schiff Base Linkage
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作者 HaiFengSONG MiaoCHEN +2 位作者 YongMinLIANG LingSHI GuoShengHUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第9期1087-1090,共4页
Novel ferrocenyl derivatives of p-(10-mercaptodecyloxy) benzal 4-ferrocenylaniline have been prepared and characterized by element analysis, 1HNMR, and FAB-MS. Cyclic voltammetry has been used to characterize the self... Novel ferrocenyl derivatives of p-(10-mercaptodecyloxy) benzal 4-ferrocenylaniline have been prepared and characterized by element analysis, 1HNMR, and FAB-MS. Cyclic voltammetry has been used to characterize the self-assembled monolayers formed from the compounds on the gold electrodes. 展开更多
关键词 Schiff base ferrocenyl derivative slef-assembly cyclic voltammetry.
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Novel Mannich Bases of Benzimidazole Derivatives: An Antibacterial Study of Environmental Bacterial Strains
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作者 Evrard Ablo Ouehi Dosso +6 位作者 Bakary Coulibaly Kouassi Franscesco Adingra Penayori Marie-Aimée Coulibaly Armand Patrick Achi Tchambaga Etienne Camara Souleymane Coulibaly Siomenan Coulibali 《Advances in Biological Chemistry》 2023年第5期182-191,共10页
A previous study was conducted on the synthesis and antibacterial evaluation of Mannich bases of 2-(thioalkyl)-1H-methylbenzimidazole derivatives. The results of this study showed that certain 2-(thioalkyl)-1H-methylb... A previous study was conducted on the synthesis and antibacterial evaluation of Mannich bases of 2-(thioalkyl)-1H-methylbenzimidazole derivatives. The results of this study showed that certain 2-(thioalkyl)-1H-methylbenzimidazole and 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl)benzimidazole derivatives possess antibacterial activities against clinical strains, such as Escherichia coli, Klebsiella pneumonia (Gram-negative bacteria), Staphylococcus aureus and Pseudomonas aeruginosa (Gram-positive bacteria). Following these favorable results, we extended the antibacterial evaluation of this series of molecules to environmental strains. The aim of this study was to assess the impact of the methyl-piperidine group fixed at position-1 of this new series of benzimidazoles on the antibacterial activity of environmental strains. In addition, we first evaluated the antibacterial activity of four 2-(thioalkyl)methylbenzimidazole derivatives and then that of five 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives. This study allowed us to show that compounds 1d and 1e could inhibit bacterial growth in vitro of the Enterobacteria P1 strain with inhibition diameters of 17.3 ± 0.6 mm and 10 ± 0.0 mm, respectively. However, addition of methyl-piperidinyl in this series showed that five (5) of 2-(thioalkyl)-methyl-1-(piperidin-1-ylmethyl) benzimidazole derivatives had an inhibitory effect on the in vitro growth of bacterial strains used except on Enterobacteria P2 with inhibition diameters between 10.0 ± 0.8 mm and 27.9 ± 1.4 mm. The introduction of the methyl-piperidinyl group at the 1-position of 2-(thioalkyl)-1H-methylbenzimidazole derivatives greatly improved the antibacterial activity against environmental bacteria such as Escherichia coli A1, A2, A3, and A4 and two Enterobacteria P1. 展开更多
关键词 Methylbenzimidazole derivatives Inhibit Bacterial Growth Mannich base ENTEROBACTERIA Escherichia coli
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A New Schiff Base Derivatives Designed to Bind Metal Ion (Cu, Co): Thermodynamics and Biological Activity Studies
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作者 Hanaa Hameed Haddad 《American Journal of Analytical Chemistry》 2016年第5期446-451,共6页
Schiff<sup> </sup>base synthesis is usually acid catalyzed and it usually requires refluxing the mixture of aldehydes and amine in ethanolic solution. Synthesis and characterization of Schiff base ligands ... Schiff<sup> </sup>base synthesis is usually acid catalyzed and it usually requires refluxing the mixture of aldehydes and amine in ethanolic solution. Synthesis and characterization of Schiff base ligands derived from substituted amine and salicylaldehyde and their complexes (Cu<sup>2+</sup>, Co<sup>2+</sup>) are reported. The ligands and ligand-complexes were characterized by melting point, FTIR, CHN-elemental analysis and UV-Visible analysis. The UV-Visible and elemental analysis of complexes established (1:2) mole ratio (M:L). The stability constant and thermodynamic parameters (K, ΔG, ΔH, ΔS) were determined at different temperature (30 - 40)°C which established that the metal-complexes were very stable. The review describes the promising biological<sup> </sup>activities of Schiff base and their metal complexes. 展开更多
关键词 Schiff base derivatives COMPLEXES Thermodynamic Parameters FTIR-Spectra Mole Ratio Method CHN Analysis Biological Activity Studies
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STUDIES ON THE PROPERTIES OF SCHIFF BASE TYPE ARYLMERCURY COMPOUNDS.II ^(199)Hg NMR SPECTRA OF MERCURATED DERIVATIVES OF SUBSTITUTED BENZYLIDENEANILINES
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作者 Yang Jie WU Kui Ling DING Department of Chemistry,Zhengzhou University,Zhengzhou,450052.Li YANG Lanzhou University,National Applied Laboratory of Organic Chemistry,Lanzhou,730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期677-680,共4页
^(199)Hg NHR spectra of 18 Schiff base type arylmercury compounds have been studied.It was further confirmed that in the molecule of XC_6H_4CH=NC_6H_3-2-HgC1-4-CH_3 there exists an intramolecular N→Hg coordination vi... ^(199)Hg NHR spectra of 18 Schiff base type arylmercury compounds have been studied.It was further confirmed that in the molecule of XC_6H_4CH=NC_6H_3-2-HgC1-4-CH_3 there exists an intramolecular N→Hg coordination via a four-membered ring.For the series of XC_6H_4CH=NC_6H_3-2-HgCl-4-CH_3(X is a para-or mera-substituent),there is a good linear correlation between δ^(199)Hg and Hammett's o constants.The influence of substituents of C-pheny1 ring on the δ ^(199)Hg can be explained in terms of the intramolecular N→Hg coordination. 展开更多
关键词 Hg NMR SPECTRA OF MERCURATED derivatives OF SUBSTITUTED BENZYLIDENEANILINES STUDIES ON THE PROPERTIES OF SCHIFF base TYPE ARYLMERCURY COMPOUNDS.II NMR
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Synthesis and spectral studies of macrocyclic Pb(Ⅱ),Zn(Ⅱ),Cd(Ⅱ)and La(Ⅲ) complexes derived from 1,4-bis(3-aminopropoxy)butane with metal nitrate and salicylaldehyde derivatives
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作者 Salih Ilhan Hamdi Temel Salih Pasa 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第3期339-343,共5页
Eight new macrocyclic complexes were synthesized by template reaction of 1,4-bis(3-aminopropoxy)butane with metal nitrate and 1,3-bis(2-formylphenyl)propane or 1,4-bis(2-formylphenyl)butane and their structures ... Eight new macrocyclic complexes were synthesized by template reaction of 1,4-bis(3-aminopropoxy)butane with metal nitrate and 1,3-bis(2-formylphenyl)propane or 1,4-bis(2-formylphenyl)butane and their structures were proposed on the basis of elemental analysis, FTIR, UV-vis, molar conductivity measurements, ^1H NMR and mass spectra. The metals to ligand molar ratios of the complexes were found to be 1: 1. The complexes are 1:2 electrolytes for Pb(II), Zn(II) and Cd(II) complexes and 1:3 electrolytes for La(III) as shown by their molar conductivities (Am) in DMSO at 10^-3 mol L^-1. Due to the existence of free ions in these complexes, such complexes are electrically conductive. The configurations of La(III) and Pb(II) were proposed to probably octahedral and Zn(II) and Cd(II) complexes were proposed to probably tetrahedral. 展开更多
关键词 Macrocyclic Schiff base Macrocyclic complexes Salicylaldehyde derivatives 1 4-Bis(3-aminopropoxy)butane
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Preparation and Characterization of Multiester Derivative from Plant Oil as Base Stock for Biolubricants
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作者 Li Xiong Chen Ligong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第2期122-128,共7页
As an alternative to petroleum-based lubricants, which are harmful to the environment in excessive amounts, a biodegradable multiester derivative(OFANE) was obtained from plant oil through a chemical modification proc... As an alternative to petroleum-based lubricants, which are harmful to the environment in excessive amounts, a biodegradable multiester derivative(OFANE) was obtained from plant oil through a chemical modification process with four steps as follows: hydrolysis, esterification, epoxidation, and ring-opening reaction. The physical and chemical properties of OFANE, such as viscosity, acid value, pour point, evaporation loss, and oxidation induction time were measured. Results showed that OFANE had good low-temperature fluidity, thermal-oxidative stability, and tribological properties. The tribological properties of OFANE with dimeric acid additive were evaluated. The final biodegradation experiment indicated that OFANE had excellent biodegradability. The prepared OFANE showed great potential as substitute for petroleum-based lubricating base oils. 展开更多
关键词 plant oil multiester derivative lubricant base oil physicochemical property tribological property
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Synthesis and Crystal Structure of a New 2D O-bridged Copper(Ⅱ) Coordination Polymer Constructed from Sulfonate-derived Schiff Base 被引量:1
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作者 欧阳淼 李家明 +3 位作者 蒋毅民 刘旭辉 张晖英 廖蓓玲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第2期299-305,共7页
A new chain-like coordination polymer, namely, [CuL]n (1, Na2L = 2-[(2-hydroxy- benzylidene)-amino]-benzenesulfonic acid sodium salt), has been synthesized and characterized by single-crystal X-ray diffraction, IR... A new chain-like coordination polymer, namely, [CuL]n (1, Na2L = 2-[(2-hydroxy- benzylidene)-amino]-benzenesulfonic acid sodium salt), has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analysis. Complex 1 crystallizes in monoclinic system, space group P21/c with a = 9.2296(16), b = 10.4754(18), c = 12.200(2) A, β = 102.392(2)°, V = 1152.0(3)A3, CI3H9CuNOaN, Mr = 338.83, Dc = 1.953 g/cm3, Z = 4, F(000) = 684, p = 2.089 mm-1, the final R = 0.0376 and wR = 0.0956. X-ray diffraction analyses indicate that 1 displays a square-pyramidal metal center with NO4 donor sets. The sulfonate-derived Schiff base serves as a common N,O,O'-tridentate and a unique O-bridged ligand connecting the metals. Dinuclear copper complexes serve as secondary building blocks (SBUs) to construct an unusual 2D coordination network. In the crystal, the components form a stable 3D supramolecular architecture by C-H...O interactions and to-stacking 展开更多
关键词 sulfonate-derived Schiff base copper(II) complex synthesis crystal structure
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Synthesis, Characterization and Crystal Structure of Cobalt(II) Complex of a Schiff Base Derived from Isoniazid and Pyridine-4-Carboxaldehyde
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作者 Evans N. Mainsah Sally-Judith E. Ntum +3 位作者 Mariam Asseng Conde George T. Chi James Raftery Peter T. Ndifon 《Crystal Structure Theory and Applications》 2019年第4期45-56,共12页
A new hydrogen bonded Cobalt(II) Schiff base complex,?N’-(pyridine-4-carboxaldehyde) isonicotinoylhydrazone Cobalt(II), has been synthesized from isoniazid and pyridine-4-carboxaldehyde and characterized by IR spectr... A new hydrogen bonded Cobalt(II) Schiff base complex,?N’-(pyridine-4-carboxaldehyde) isonicotinoylhydrazone Cobalt(II), has been synthesized from isoniazid and pyridine-4-carboxaldehyde and characterized by IR spectroscopy, 1H-NMR, elemental analysis, TGA and single crystal X-ray structure determination. X-ray crystal structure analysis shows an octahedral complex with a metal centre coordinated to two ligand molecules through the pyridine nitrogen atoms and four water molecules and containing two nitrate groups as counter ions. The complex crystallizes in the monoclinic crystal system and P2(1)/n space group. The unit cell dimensions are: a = 7.2108(4) &Aring;, b = 16.6020(9) &Aring;, c = 13.0389(6) &Aring;,α = 90°, β = 103.972(4)°, γ = 90°. The molecule is symmetrical about the cobalt centre as observed from the 1H-NMR and 13C-NMR and confirmed by the single crystal X-ray structure of the complex. Thermogravimetric analysis shows two steps decomposition of the complex to leave a metal oxide residue. The title compound is expected to be biologically active as one of the precursors (isoniazid) is a therapeutic agent with well-established clinical applications. 展开更多
关键词 PYRIDINE derivatives Cobalt(II) COMPLEX Isonicotinoylhydrazone Pyridine-4-Carboxaldehyde Schiff base HETEROCYCLIC Compound X-Ray Structure
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NEW SOLID BASE DERIVED FROM AIPO4-5 SUPPORTED KF
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作者 Jian Hua ZHU Qin Hug XU Hideshi HATTORI(Chemistry Department, Nanjing University.Nanjing 210093,China.)(Centre for Advanced Research of Energy Technology, Hokkaido University,Sapporo 060.Japan) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第7期671-674,共4页
Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the iso... Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the isomerization of butenes at 273K. and the activity increasedwith the pre-treatment temperature up to 923K. 展开更多
关键词 NEW SOLID base derivED FROM AIPO4-5 SUPPORTED KF
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COMPLEXES OF RARE EARTH NITRATE WITH SCHIFF BASE DERIVED FROM VANILLIN AND P-TOLUIDINE
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作者 Guo Fa LIU Bin LI Chong wu NA Kun Yuan MAO Institute of Material Science,Jilin University,Changchun,130023 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期119-120,共2页
In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and ... In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-Eu except Pm,L=Schiff base ligand) have been prepared and characterized. 展开更多
关键词 COMPLEXES OF RARE EARTH NITRATE WITH SCHIFF base derivED FROM VANILLIN AND P-TOLUIDINE
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Derivative-Based Midpoint Quadrature Rule
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作者 Clarence O. E. Burg Ezechiel Degny 《Applied Mathematics》 2013年第1期228-234,共7页
A new family of numerical integration formula is presented, which uses the function evaluation at the midpoint of the interval and odd derivatives at the endpoints. Because the weights for the odd derivatives sum to z... A new family of numerical integration formula is presented, which uses the function evaluation at the midpoint of the interval and odd derivatives at the endpoints. Because the weights for the odd derivatives sum to zero, the derivative calculations cancel out for the interior points in the composite form, so that these derivatives must only be calculated at the endpoints of the overall interval of integration. When using N subintervals, the basic rule which uses the midpoint function evaluation and the first derivative at the endpoints achieves fourth order accuracy for the cost of N/2 function evaluations and 2 derivative evaluations, whereas the three point open Newton-Cotes method uses 3N/4 function evaluations to achieve the same order of accuracy. These derivative-based midpoint quadrature methods are shown to be more computationally efficient than both the open and closed Newton-Cotes quadrature rules of the same order. This family of derivative-based midpoint quadrature rules are derived using the concept of precision, along with the error term. A theorem concerning the order of accuracy of quadrature rule using the concept of precision is provided to justify its use to determine the leading order error term. 展开更多
关键词 NUMERICAL INTEGRATION NUMERICAL QUADRATURE Midpoint Rule Open Newton-Cotes INTEGRATION derivative-based QUADRATURE
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新型多取代Trger’s base衍生物的合成及其晶体结构 被引量:1
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作者 李正义 庄跃 +2 位作者 朱美兰 殷乐 孙小强 《合成化学》 CAS CSCD 2017年第8期629-636,共8页
以邻氨基二苯甲酮为原料,经两分子环化缩合反应制得6,12-二芳基二苯并[b,f][1,5]二氮杂环辛四烯(2a^2d);2a^2d经Li Al H4还原制得6,12-二芳基-5,6,11,12-四氢二苯并[b,f][1,5]二氮杂环辛(3a^3d);3a^3d与醛(或酮)反应,合成了一系列新型... 以邻氨基二苯甲酮为原料,经两分子环化缩合反应制得6,12-二芳基二苯并[b,f][1,5]二氮杂环辛四烯(2a^2d);2a^2d经Li Al H4还原制得6,12-二芳基-5,6,11,12-四氢二苯并[b,f][1,5]二氮杂环辛(3a^3d);3a^3d与醛(或酮)反应,合成了一系列新型的多取代Trger’s base衍生物(4a^4d和5a^7a),其结构经1H NMR,13C NMR,HR-MS(ESI)和X-射线单晶衍射表征。通过分析架桥前后3a(CCDC:1498564)和6a(CCDC:1498555)的晶体结构,解释了该类化合物1H NMR中NCH质子及桥上取代基质子裂分的原因,并进一步证实了4~7为非C2轴对称结构。 展开更多
关键词 多取代Troger’s base衍生物 合成 晶体结构 质子裂分
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4-吡啶基-2-肼基噻唑缩酰基芘Schiff Base的合成
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作者 王桂林 石玉芳 +1 位作者 孙金鱼 赵明根 《中北大学学报(自然科学版)》 CAS 北大核心 2015年第6期689-695,共7页
首先由乙酰吡啶经溴代制得ω-溴代乙酰基吡啶氢溴酸盐(1);其次,由氨基硫脲与酰基芘反应,制得酰基芘缩氨基硫脲(2);最后由(1)与(2)反应得到目标产物4-吡啶基-2-肼基噻唑缩酰基芘SchiffBase(3),其结构经~1H NMR、IR、元素分析... 首先由乙酰吡啶经溴代制得ω-溴代乙酰基吡啶氢溴酸盐(1);其次,由氨基硫脲与酰基芘反应,制得酰基芘缩氨基硫脲(2);最后由(1)与(2)反应得到目标产物4-吡啶基-2-肼基噻唑缩酰基芘SchiffBase(3),其结构经~1H NMR、IR、元素分析和质谱表征.结果表明,(3)的分子结构属推拉电子型的多芳香大π共轭体系,并因熔点在240℃以上而表现出良好的热稳定性,可望有潜在非线性光学性质并作为非线性光学材料用于器件制作. 展开更多
关键词 芘衍生物 4-吡啶基-2-肼基噻唑缩酰基芘 希夫碱 合成 非线性光学材料
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Current applications of adipose-derived stem cells and their future perspectives 被引量:22
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作者 Eun-Hee Kim Chan Yeong Heo 《World Journal of Stem Cells》 SCIE CAS 2014年第1期65-68,共4页
Adult stem cells have a great potential to treat various diseases. For these cell-based therapies, adipose-derived stem cells(ADSCs) are one of the most promising stem cell types, including embryonic stem cells(ESCs) ... Adult stem cells have a great potential to treat various diseases. For these cell-based therapies, adipose-derived stem cells(ADSCs) are one of the most promising stem cell types, including embryonic stem cells(ESCs) and induced pluripotent stem cells(iPSCs). ESCs and iPSCs have taken center stage due to their pluripotency. However, ESCs and iPSCs have limitations in ethical issues and in identification of characteristics, respectively. Unlike ESCs and iPSCs, ADSCs do not have such limitations and are not only easily obtained but also uniquely expandable. ADSCs can differentiate into adipocytes, osteoblasts, chondrocytes, myocytes and neurons under specific differentiation conditions, and these kinds of differentiation potential of ADSCs could be applied in regenerative medicine e.g., skin reconstruction, bone and cartilage formation, etc. In this review, the current status of ADSC isolation, differentiation and their therapeutic applications are discussed. 展开更多
关键词 Adipose-derived STEM cells ISOLATION DIFFERENTIATION TRANSPLANTATION Cell-based THERAPY
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Application of hybrid robust three-axis attitude control approach to overactuated spacecraft——A quaternion based model 被引量:2
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作者 A.H.Mazinan 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1740-1753,共14页
A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that th... A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that the new insights may be taken into account as decision points to outperform the available materials. It is to note that the traditional control approaches may generally be upgraded, as long as a number of modifications are made with respect to state-of-the-art, in order to propose high-precision outcomes. Regarding the investigated issues, the robust sliding mode finite-time control approach is first designed to handle three-axis angular rates in the inner control loop, which consists of the pulse width pulse frequency modulations in line with the control allocation scheme and the system dynamics. The main subject to employ these modulations that is realizing in association with the control allocation scheme is to be able to handle a class of overactuated systems, in particular. The proportional derivative based linear quadratic regulator approach is then designed to handle three-axis rotational angles in the outer control loop, which consists of the system kinematics that is correspondingly concentrated to deal with the quaternion based model. The utilization of the linear and its nonlinear terms, simultaneously, are taken into real consideration as the research motivation, while the performance results are of the significance as the improved version in comparison with the recent investigated outcomes. Subsequently, there is a stability analysis to verify and guarantee the closed loop system performance in coping with the whole of nominal referenced commands. At the end, the effectiveness of the approach considered here is highlighted in line with a number of potential recent benchmarks. 展开更多
关键词 three-axis angular rates and rotations sliding mode finite-time control approach proportional derivative based linearquadratic regulator approach dynamics and kinematics of overactuated spacecraft
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Current progress in use of adipose derived stem cells in peripheral nerve regeneration 被引量:8
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作者 Shomari DL Zack-Williams Peter E Butler Deepak M Kalaskar 《World Journal of Stem Cells》 SCIE CAS 2015年第1期51-64,共14页
Unlike central nervous system neurons; those in the peripheral nervous system have the potential for full regeneration after injury. Following injury, recovery is controlled by schwann cells which replicate and modula... Unlike central nervous system neurons; those in the peripheral nervous system have the potential for full regeneration after injury. Following injury, recovery is controlled by schwann cells which replicate and modulate the subsequent immune response. The level of nerve recovery is strongly linked to the severity of the initial injury despite the significant advancements in imaging and surgical techniques. Multiple experimental model shave been used with varying successes to augment the natural regenerative processes which occur following nerve injury. Stem cell therapy in peripheral nerve injury may be an important future intervention to improve the best attainable clinical results. In particular adipose derived stem cells(ADSCs) are multipotent mesenchymal stem cells similar to bone marrow derived stem cells, which are thought to have neurotrophic properties and the ability to differentiate into multiple lineages. They are ubiquitous within adipose tissue; they can form many structures resembling the mature adult peripheral nervous system. Following early in vitro work; multiple small and large animal in vivo models have been used in conjunction with conduits, autografts and allografts to successfully bridge the peripheral nerve gap. Some of the ADSC related neuroprotective and regenerative properties have been elucidated however much work remains before a model can be used successfully in human peripheral nerve injury(PNI). This review aims to provide a detailed overview of progress made in the use of ADSC in PNI, with discussion on the role of a tissue engineered approach for PNI repair. 展开更多
关键词 PERIPHERAL NERVE INJURY ADIPOSE derivedstem CELLS Cell based THERAPIES Stem CELLS
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A Filter-Based Pattern Search Method for Unconstrained Optimization 被引量:4
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作者 Ting Wu Linping Sun 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第3期209-216,共8页
We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provi... We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provide a new criterion of iterate acceptance. The convergence can be ensured under some conditions. The numerical result shows that this method is practical and efficient. 展开更多
关键词 直接搜索 模型搜索 滤波器 无约束优化
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Crystal Structure of Derivative of H_4′-NOBIN and the Applications in Hetero-Diels-Alder Reaction
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作者 牧初春 李新生 徐东成 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第2期205-209,共5页
Novel Schiff bases of H4'-NOBIN 5a and 5b were synthesized by condensation of 3 with aldehydes. Compound 5b was structurally characterized by single-crystal X-ray diffraction. The asymmetric hetero-Diels-Alder reacti... Novel Schiff bases of H4'-NOBIN 5a and 5b were synthesized by condensation of 3 with aldehydes. Compound 5b was structurally characterized by single-crystal X-ray diffraction. The asymmetric hetero-Diels-Alder reactions were carried out with high yields and good enantioselectivities in the presence of Ti-(S)-5a complex as catalyst. Crystallographic data for 5b: C27H22BrNO, Mr = 456.37, triclinic, space group P1 with a = 9.1618(2), b = 10.3836(2), c = 12.7718(2) А,α=105.4860(10),β= 94.6360(10), γ= 108.4610(10)°, V= 1092.32(4)А^3, Z=2, Dc= 1.388 g/cm^3, μ= 1.900 mm^-1, F(000) = 468, R = 0.0476 and wR = 0.1248 for 3092 observed reflections (I〉 2σ(I)). 展开更多
关键词 crystal structure BINOL derivative Schiff bases Diels-Alder reactions
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Detection of Edge with the Aid of Mollification Based on Wavelets
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作者 Tohru Morita Ken-Ichi Sato 《Applied Mathematics》 2014年第18期2849-2861,共13页
In preceding papers, the present authors proposed the application of the mollification based on wavelets to the calculation of the fractional derivative (fD) or the derivative of a function involving noise. We study h... In preceding papers, the present authors proposed the application of the mollification based on wavelets to the calculation of the fractional derivative (fD) or the derivative of a function involving noise. We study here the application of that method to the detection of edge of a function. Mathieu et al. proposed the CRONE detector for a detection of an edge of an image. For a function without noise, we note that the CRONE detector is expressed as the Riesz fractional derivative (fD) of the derivative. We study here the application of the mollification to the calculation of the Riesz fD of the derivative for a data involving noise, and compare the results with the results obtained by our method of applying simple derivative to mollified data. 展开更多
关键词 Mollification EDGE DETECTOR RIESZ Fractional derivative Mollifiers based on WAVELETS Gibbs Phenomenon PRIMITIVE CRONE fD DETECTOR
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