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Characterization of single-handed,coiled,carbonaceous,tubular nanoribbons

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Chinese Chemical Letters 2014年第6期25卷 879-882页

作者： Dan liu Yong-Min Guo Yi li bao-zong li Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow University

Left-handed, coiled, 4,4＇-biphenylene bridged polybissilsesquioxane, tubular nanoribbons were prepared according to the published literature. After carbonization and removal of silica using HF aqueous solution, left-handed, coiled, carbonaceous, tubular nanoribbons were obtained. The left- handed, coiled, carbonaceous, tubular nanoribbons were characterized using field-emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, Raman spectropho- tometer, diffuse reflectance circular dichroism （DRCD）, and N2 adsorptions. Micropores were formed due to the removal of silica. The nitrogen BET surface area is 1727 m2/g. A broad, positive DRCD signal, identified at 400-800 rim, indicates the carbonaceous, tubular nanoribbons exhibit optical activity. The helical pitch is proposed to play an important role in the position of the DRCD signal.

关键词： Nanoparticles Carbon/silica Sol-gel preparation Structural

Preparation of single-handed helical phenolic resin nanoflbers using a supramolecular templating method

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Chinese Chemical Letters 2014年第10期25卷 1363-1366页

作者： li-Qing Ma Hao Chen Yong-Min Guo bao-zong li Yi li Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow University

Single-handed helical phenolic resin nanofibers were synthesized through a supramolecular templating approach using the supramolecular self-assemblies of a pair of chiral low-molecular-weight amphiphiles as the templates and 2,4-dihydroxybenzoic acid and formaldehyde as the *** phenolic resin nanofibers were characterized using field-emission scanning electron microscopy,transmission electron microscopy and diffused reflection circular *** results indicated that the chirality of the supramolecular self-assemblies was successfully transferred to the phenolic resin *** left- and right-handed helical phenolic resin nanofibers exhibited opposite optical activity.

关键词： Supramolecular template Chirality Phenolic resins Nanofibers

A chirality indicator for the walls and the surfaces of silica nanotubes

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Chinese Chemical Letters 2013年第8期24卷 770-772页

作者： Feng-Wen Hou li-Min Wu Yong-Min Guo Yi li bao-zong li Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow University

Single-handed helical silica nanotubes were prepared according to the literature procedures,using the self-assemblies of a pair of chiral cationic low-molecular-weight gelators as the templates.A chirality indicator,4,4＇-bis（triethoxysilyl）-1,1＇-biphenyl,was developed to determine the chirality of the silica *** chirality of the surfaces and the bulky walls of the silica nanotubes were understood from the twist of the biphenylene rings.

关键词： Sol-gel transcription Nanoparticles Silica nanotubes Self-assembly Chirality indicator

Water solubility enhancements of PAHs by sodium castor oil sulfonate microemulsions

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Journal of Environmental Sciences 2003年第5期15卷 583-589页

作者： ZHU li zhong *, ZHAO bao wei, li zong lai (Department of Environmental Science, Zhejiang University, Hangzhou 310028, China.) Department of Environmental Science Zhejiang University Hangzhou 310028 Chin

Water solubility enhancements of naphthalene(Naph), phenantherene(Phen) and pyrene(Py) in sodium castor oil sulfonate(SCOS) microemulsions were evaluated. The apparent solubilities of PAHs are linearly proportional to the concentrations of SCOS microemulsion, and the enhancement extent by SCOS solutions is greater than that by ordinary surfactants on the basis of weight solubilization ratio(WSR). The log K em values of Naph, Phen, and Py are 3 13, 4 44 and 5 01 respectively, which are about the same as the log K ow values. At 5000 mg/L of SCOS conccentration, the apparent solubilities are 8 80, 121, and 674 times as the intrinsic solubilities for Naph, Phen, and Py. The effects of inorganic ions and temperature on the solubilization of solutes are also investigated. The solubilization is improved with a moderate addition of Ca 2+ , Na +, NH + 4 and the mixture of Na +, K +, Ca 2+ , Mg 2+ and NH + 4. WSR values are enhanced by 22 0% for Naph, 23 4% for Phen, and 24 6% for Py with temperature increasing by 5℃. The results indicated that SCOS microemulsions improve the performance of the surfactant enhanced remediation(SER) of soil, by increasing solubilities of organic pollutants and reducing the level of surfactant pollution and remediation expenses.

关键词： sodium castor oil sulfonate microemulsion solubilization PAHs

Preparation and characterizations of helical mesoporous silica nanorods using CTAB and alcohols

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Chinese Chemical Letters 2012年第10期23卷 1201-1204页

作者： Yun Yue Pu Yi li Wei Zhuang Ming Zhang bao zong li Yong Gang Yang Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Helical mesoporous silica nanorods were prepared using cetyltrimethylammonium bromide and achiral alcohols as the co-structure-directing agents. They were characterized using field-emission scanning electron microscopy, transmission electron microscopy, nitrogen sorptions, and small angle X-ray diffraction. The length of the silica nanorods increases with increasing the length of the alcohols. When n-heptanol and n-octanol were used, helical mesoporous silica nanorods with lamellar mesopores on the surfaces were obtained.

关键词： Mesoporous Alcohols Surfactant Helical Sol-gel processes

Preparation of optical active single-handed helical barium titanate nanotubes and characterization of dielectric properties

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Chinese Chemical Letters 2017年第5期28卷 1111-1113页

作者： Shu-Wei lin Wen-Hu Qian Hong-Jing Huo bao-zong li Yi li Yong-Gang Yang Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Left and right-handed helical barium titanate nanotubes are prepared with the impregnation of Ba（OH）2 into single-handed helical titania *** angle X-ray diffraction pattern and transmission electron microscopy image indicate that they are constructed by nanoparticles with a partially crystalline *** diffuse reflertance circular dichroism spectra indicate that they exhibit optical activity which was proposed to originate from chiral defects on the inner surfaces of the *** the dielectric constant and tanδ decrease with increasing the *** 10 and 100 Hz,one dielectric constant peak at 9.6℃ and one tanδ peak at 5.0℃ are observed at -120℃ to 180℃.

关键词： Dielectrics Barium titanate Optical materials and properties Templating approach Nanoparticles

Theoretical Study on Reaction Mechanism of Tautomerization of Indazole and 3-halogeno-indazole

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Chinese Journal of Chemical Physics 2006年第3期19卷 233-237页

作者： Hai-yan Yu bao-zong li Yong-min Guo Chemistry and Chemical Engineering Suzhou University Suzhou 215006 China Department of Chemistry Yancheng Normal College Yancheng 224002 China

The molecular structures of indazole and 3-halogeno-indazole tautomers were calculated by the B3LYP method at the 6-311G^＊＊ level, both in the gaseous and aqueous phases, with full geometry optimization. The geometry and electronic structure of the tautomers of indazole, 3-halogeno-indazole and their transition states were obtained. The Onsager solvate theory model was employed for the aqueous solution calculations. The results of the calculation indicated that the N1-H form of the studied molecule is more stable than that of the N2-H form. The influences of the different 3-halogeno and solvent effects on the geometry, energy, charge and activation energy were discussed. The reaction mechanism of the tautomerization of indazole and 3-halogeno-indazole was also studied and a three-membered cyclic transition state of the tautomer reaction has been obtained.

关键词： 3-halogeno-indazole Tautomers Transition states Activation energy DFT

Structural Evolution of Ultra-High Molecular Weight Polyethylene Low-Entangled Films with Reserved Shish Crystals During Hot Stretching

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Chinese Journal of Polymer Science 2024年第8期42卷 1227-1242页

作者： Jia-Wei Gao li Chen Ye-Shun Zhong Chao-Wei Xing Yi-Guo li zong-bao Wang School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

Shish crystals are crucial to achieving high performance low-dimensional ultra-high molecular weight polyethylene(UHMWPE)***,high stretch and shear flow fields are necessary for the formation of shish *** this study,UHMWPE gel films with reserved shish crystals were prepared by gel molding,the structural evolution and properties of UHMWPE films stretched at temperatu res of 100,110,120and 130℃were investigated by in situ small-angle X-ray scattering(SAXS)/ultra-small-angle X-ray scattering(USAXS)/wide-angle X-ray diffraction(WAXD)measu rements as well as scanning electron microscopy(SEM)and differential scanning calorimetry(DSC)*** findings showed that the reserved shish crystals can facilitate the formation and structural evolution of shish-kebab crystals during the hot ***,the reserved shish crystals promote the structu ral evolution of UHMWPE films to a greater extent when stretched at 120 and 130℃,compared to 100 and 110℃,resulting in higher crystallinity,orientation,thermal properties,breaking strength and Young's *** pared to UHMWPE high-entangled films with reserved shish crystals prepared by compression molding,UHMWPE low-entangled films with reserved shish crystals prepared by gel molding are more effective in inducing the formation and evolution of shish-kebab crystals during the hot stretching,resulting in increased breaking strength and Young's modulus.

关键词： UHMWPE low-entangled films Reserved shish crystals Structural evolution Hot stretching

Design and fabrication of lightweight AlCrFeNiTi_(x) compositionally complex alloys with exceptional specific strength

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Rare Metals 2024年第7期43卷 3314-3328页

作者： Jun-Zhi li Wei-zong bao Jie Chen Bo-Hua Yu Kun Zuo Tian Gao Ze-Yun Cai Guo-Qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace *** composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic *** CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum *** incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific *** effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance *** exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of *** methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.

关键词： lightweight Compositionally complex alloys Specific yield strength