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Large-scale synthesis of polyynes with commercial laser marking technology
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作者 Liang Fang Yanping Xie +1 位作者 Shujie Sun Wei Zi 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期425-428,共4页
The space-confined synthesis method has been an efficient way for the preparation of linear carbon chains.However,the large-scale preparation of linear carbon chains still faces many challenges due to the lack of meth... The space-confined synthesis method has been an efficient way for the preparation of linear carbon chains.However,the large-scale preparation of linear carbon chains still faces many challenges due to the lack of methods for the large-scale synthesis of precursors,such as short carbon chains(polyynes),and regulation technology for the transport of reactants in one-dimensional space.Here,we report a facile method for the rapid preparation of polyynes in large quantities using a commercial laser marking machine.Spectroscopic characterizations show that a large number of polyynes,such as C_(8)H_(2),C_(10)H_(2),C_(12)H_(2),and C_(14)H_(2),can be produced by ablating the graphite plate immersed in the organic liquid using a laser marking machine.The results of in situ Raman spectroscopy investigation of C_(2n)H_(2)-filled single-walled carbon nanotubes further confirm that a variety of polyyne molecules are synthesized.Meanwhile,in situ Raman spectroscopy also shows that the local heating treatment can accelerate the filling process of C_(2n)H_(2)into one-dimensional channels.This work provides new insights into the study of linear carbon chains and space-confined synthesis methods. 展开更多
关键词 polyynes carbon chains single-walled carbon nanotubes
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Nitrogen-tailored quasiparticle energy gaps of polyynes
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作者 Kan Zhang Jiling Li +2 位作者 Peitao Liu Guowei Yang Lei Shi 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期170-174,共5页
Polyyne,an sp~1-hybridized linear allotrope of carbon,has a tunable quasiparticle energy gap,which depends on the terminated chemical ending groups as well as the chain length.Previously,nitrogen doping was utilized t... Polyyne,an sp~1-hybridized linear allotrope of carbon,has a tunable quasiparticle energy gap,which depends on the terminated chemical ending groups as well as the chain length.Previously,nitrogen doping was utilized to tailor the properties of different kinds of allotrope of carbon.However,how the nitrogen doping tailors the properties of the polyyne remains unexplored.Here,we applied the GW method to study the quasiparticle energy gaps of the N-doped polyynes with different lengths.When a C atom is substituted by an N atom in a polyyne,the quasiparticle energy gap varies with the substituted position in the polyyne.The modification is particularly pronounced when the second-nearest-neighboring carbon atom of a hydrogen atom is substituted.In addition,the nitrogen doping makes the Fermi level closer to the lowest unoccupied molecular orbital,resulting in an n-type semiconductor.Our results suggest another route to tailor the electronic properties of polyyne in addition to the length of polyyne and the terminated chemical ending groups. 展开更多
关键词 polyyne NITROGEN-DOPING quasiparticle energy gap GW calculations
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Pharmacokinetic profiles of falcarindiol and oplopandiol in rats after oral administration of polyynes extract of Oplopanax elatus 被引量:2
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作者 SUN Wei HE Yi-Sheng +5 位作者 XU Ling-Hui ZHANG Bi-Ying QI Lian-Wen YANG Jie LI Ping WEN Xiao-Dong 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第9期714-720,共7页
Polyynes, such as facarindiol(FAD) and oplopandiol(OPD), are responsible for anticancer activities of Oplopanax elatus(O. elatus). A novel approach to pharmacokinetics determination of the two natural polyynes in rats... Polyynes, such as facarindiol(FAD) and oplopandiol(OPD), are responsible for anticancer activities of Oplopanax elatus(O. elatus). A novel approach to pharmacokinetics determination of the two natural polyynes in rats was developed and validated using a liquid chromatography-electrospray ionization-mass spectrometry(LC-MS) method. Biosamples were prepared by liquid-liquid extraction using ethyl acetate/n-hexane(V : V = 9 : 1) and the analytes were eluted on an Agilent ZORBAX Eclipse Plus C18 threaded column(4.6 mm × 50 mm, 1.8 μm) with the mobile phase of acetonitrile-0.1% aqueous formic acid at a flow-rate of 0.5 m L·min–1 within a total run time of 11 min. All analytes were simultaneously monitored in a single-quadrupole mass spectrometer in the selected ion monitoring(SIM) mode using electrospray source in positive mode. The method was demonstrated to be rapid, sensitive, and reliable, and it was successfully applied to the pharmacokinetic studies of the two polyynes in rat plasma after oral administration of polyynes extract of O. elatus. 展开更多
关键词 Oplopanax elatus polyynes LC-MS Pharmacokinetic study
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HYPERBRANCHED CONJUGATIVE MACROMOLECULES CONSTRUCTED FROM TRIPLE-BOND BUILDING BLOCKS 被引量:7
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作者 Matthias HaeuBler Hong-chen Dong +3 位作者 Jacky Wing Yip Lam Rong-hua Zheng An-jun Qin Ben-zhong Tang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第6期567-591,共25页
Polycyclotrimerization and polycoupling of acetylenic monomers respectively furnish hyperbranched polyarylenes and polyynes with high molecular weights (up to 1 × 10^6) in high yields (up to 99.9%). The polym... Polycyclotrimerization and polycoupling of acetylenic monomers respectively furnish hyperbranched polyarylenes and polyynes with high molecular weights (up to 1 × 10^6) in high yields (up to 99.9%). The polymers possess low intrinsic viscosities and high thermal stabilities, losing little of their weights when heated to 〉 400℃. Upon pyrolysis at 〉 800℃, the polymers graphitize with high char yields (up to 86%). Hyperbranched polyarylenes efficiently emit deep-blue to blue-green lights with fluorescence quantum yields up to 98% and strongly attenuate intense laser pulses with optical power-limiting performances superior to that of C60, a well-known optical limiter. Poly(alkenephenylenes), poly(aroylarylenes) and polyynes are readily cross-linkable by UV irradiation, serving as excellent photoresist materials for the generation of patterns with nanometer resolution. Thin films of hyperbranched polyynes exhibit very high refractive indexes (n up to 1.86). The internal and terminal acetylene moieties of the polyynes readily form complexes with cobalt carbonyls, which can be transformed into soft ferromagnetic ceramics with high magnetic susceptibilities (Ms up to ca. 118 emu/g) and near-zero magnetic losses. 展开更多
关键词 Hyperbranched polymers Alkyne polycyclotrimerization Alkyne polycoupling POLYARYLENES polyynes Optical materials PHOTORESISTS Soft ferromagnetic ceramics
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UV-Polarizing Linear Polyyne Molecules Aligned in PVA
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作者 R. Sata H. Suzuki +3 位作者 N. Ueno Y. Morisawa M. Hatanaka T. Wakabayashi 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第2期175-181,I0002,共8页
Electronic absorption bands of conjugated linear carbon chain molecules, namely polyynes H(C≡C)nH (n=5-7), are exploited to devise light-polarizing films applicable to the UV. Laser ablated polyynes are separated in ... Electronic absorption bands of conjugated linear carbon chain molecules, namely polyynes H(C≡C)nH (n=5-7), are exploited to devise light-polarizing films applicable to the UV. Laser ablated polyynes are separated in size and dispersed in a film of polyvinyl alcohol (PVA), which is stretched to align the trapped linear polyyne molecules inside. As a nature of the structural anisotropy, transition dipole of the UV absorption for polyyne molecules is in parallel with the molecular axis and the absorption occurs only for the electromagnetic wave having the amplitude of its electric vector along the molecular axis. Aligned and fixed orientationally in the solid PVA film, polyyne molecules act as selective absorbers of one of the polarization components of incident light at particular wavelength. Using a light source of linearly polarized UV light, whose direction of polarization is rotatable, angular dependence of the absorption intensity is investigated for the stretched PVA film containing aligned polyyne molecules and analyzed in terms of an order parameter in the theory of linear dichroism. 展开更多
关键词 Polyyne UV absorption Polyvinyl alcohol Linear dichroism Linearly polarized light POLARIZER
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One-dimensional sp carbon:Synthesis,properties,and modifications
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作者 Chao-Fan Lv Xi-Gui Yang Chong-Xin Shan 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期567-589,共23页
Carbyne,as the truly one-dimensional carbon allotrope with sp-hybridization,has attracted significant interest in recent years,showing potential applications in next-generation molecular devices due to its ultimate on... Carbyne,as the truly one-dimensional carbon allotrope with sp-hybridization,has attracted significant interest in recent years,showing potential applications in next-generation molecular devices due to its ultimate one-atom thinness.Various excellent properties of carbyne have been predicted,however,free-standing carbyne sample is extremely unstable and the corresponding experimental researches and modifications are under-developed compared to other known carbon allotropes.The synthesis of carbyne has been slowly developed for the past decades.Recently,there have been several breakthroughs in in-situ synthesis and measurement of carbyne related materials,as well as the preparation of ultra-long carbon chains toward infinite carbyne.These progresses have aroused widespread discussion in the academic community.In this review,the latest approaches in the synthesis of sp carbon are summarized.We then discuss its extraordinary properties,including mechanical,electronic,magnetic,and optical properties,especially focusing on the regulations of these properties.Finally,we provide a perspective on the development of carbyne. 展开更多
关键词 CARBYNE polyyne linear carbon chains
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A review of linear carbon chains 被引量:3
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作者 Kan Zhang Yifan Zhang Lei Shi 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第7期1746-1756,共11页
Linear carbon chains(LCCs)are a one-dimensional sp1-hybridized allo trope of ca rbon.LCCs are extre mely unstable:The longer the LCCs,the less stable the materials.Thus,it is a big challenge to synthesize long LCCs.Al... Linear carbon chains(LCCs)are a one-dimensional sp1-hybridized allo trope of ca rbon.LCCs are extre mely unstable:The longer the LCCs,the less stable the materials.Thus,it is a big challenge to synthesize long LCCs.Although the research on the short LCCs,e.g.,polyynes,can be traced back to the 18th,LCCs are still not well-known compared to other allotropes of carbon,e.g.,fullerenes,carbon nanotubes and graphene.Therefore,introducing recent progress on LCCs is of great significance to draw more attention in the community of nanocarbons as well as nanomaterials in general.Theoretically,various excellent properties have been predicted.Experimentally,LCCs with different length in many kinds of forms have been successfully synthesized.In this review,we summarized recent studies of polyynic LCCs from both theoretical and experimental aspects.Also,perspectives are highlighted to point out the further investigations of the materials. 展开更多
关键词 Linear carbon chains Polyyne CARBYNE Carbon nanotubes Electronic property
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