Poly (4- methylphenoxyphosphnzene ) -graft-poly ( ethylene oxide ) ( PPZ-g- PEO ), a novel amphiphilie grafting polymer was prepared via the Decker-Forster reaction. It is found that the graft efficiency increas...Poly (4- methylphenoxyphosphnzene ) -graft-poly ( ethylene oxide ) ( PPZ-g- PEO ), a novel amphiphilie grafting polymer was prepared via the Decker-Forster reaction. It is found that the graft efficiency increased with extension of reaction time. Low molecular weight of poly ( ethylene oxide ) favored the grafting reaction. The grafted polymer has two different glass transition temperatures( Tg) with those of pure poly( 4-methyl- phenoxy-phopsphazene ) and PEO. The emulsifying ability of grafted polymer was studied with benzene-water mixtare. The emulsifying volumes increased with the decreasing of PEO' s molecular weight. The contact angle of film forming from grafted polymer decreased after introduction of PEO grafting chain.展开更多
Two new chiral mixed(phthalocyaninato)(porphyrinato)rare earth triple-decker complexes with both(R)-and(S)-enantiomers were synthesized and structurally characterized.The significant magneto-chiral cross effect reveal...Two new chiral mixed(phthalocyaninato)(porphyrinato)rare earth triple-decker complexes with both(R)-and(S)-enantiomers were synthesized and structurally characterized.The significant magneto-chiral cross effect revealed for the dysprosium compound suggests the great potential of sandwich-type tetrapyrrole rare earth systems in the research field of magneto-chiral dichroism.展开更多
Mixed(phthalocyaninato)(porphyrinato)rare earth double-decker complexes MIII(Pc)(TNP)(M=Tb(1),Dy(2),and Y(3);Pc=phthalocyaninate;TNP=tetranaphthylporphyrinate)were synthesized and characterized by elemental analysi...Mixed(phthalocyaninato)(porphyrinato)rare earth double-decker complexes MIII(Pc)(TNP)(M=Tb(1),Dy(2),and Y(3);Pc=phthalocyaninate;TNP=tetranaphthylporphyrinate)were synthesized and characterized by elemental analysis and a range of spectroscopic methods.They represent the first examples of double-decker rare earth complexes containing a tetranaphthylporphyrin ligand.展开更多
For the purpose of engineering magnetic anisotropy,chiral binaphthyl substituents with slight electron-withdrawing ability and dibutylamino substituents with intense electron-donating nature are incoporated onto the p...For the purpose of engineering magnetic anisotropy,chiral binaphthyl substituents with slight electron-withdrawing ability and dibutylamino substituents with intense electron-donating nature are incoporated onto the periphery of each phthalocyanine ligand in the bis(phthalocyaninato)terbium double-decker compound,resulting in the chiral heteroleptic bis(phthalocyaninato)terbium complex(R)/(S)-[Pc(OBNP)4]Tb{Pc[N(C4H9)2]8}(R/S-1){Pc(OBNP)4={tetrakis(dinaphtho[1,2-e:1′,2′-g]-1,4-dioxocine)[2,3-b;2′,3′-k;2″,3″-t;2″′,3″′-c′]phthalocyanine};Pc[N(C4H9)2]8=[2,3,9,10,16,17,23,24-octakis(dibutylamino)phthalocyanine]}.Magnetic studies reveal the typical single-ion magnet(SIM)nature of this chiral bis(phthalocyaninato)terbium double-decker with spin reversal energy barrier of 638 K.A butterfly-shaped magnetic hysteresis loop was observed at even 25 K for R-1 under the sweep rate of 500 Oe s-1.The performance of this SIM is well rationalized on the basis of theoretical analysis of the electrostatic potential according to calculations using the density functional theory method.展开更多
Despite the rapid progress in the research on the synthesis of linear macromolecular systems with double-decker SQs included in the co-polymer chain,based on diverse catalytic processes,it still has limitations becaus...Despite the rapid progress in the research on the synthesis of linear macromolecular systems with double-decker SQs included in the co-polymer chain,based on diverse catalytic processes,it still has limitations because of the formation of co-oligomers up to 20 units in a chain.Herein,we present a distinct look at known hydrosilylation reactions for forming hybrid copolymers.展开更多
Herein,we disclose an unexpected Si–O–Si cage reorganization that was observed during the standard hydrolytic condensation procedure of tetrasilanol double-decker silsesquioxane(DDSQ)with respective mono-and di-chlo...Herein,we disclose an unexpected Si–O–Si cage reorganization that was observed during the standard hydrolytic condensation procedure of tetrasilanol double-decker silsesquioxane(DDSQ)with respective mono-and di-chlorosilanes.The investigation of this process allowed us to propose the possible mechanism of this transformation.The formation of all structures was confirmed by NMR,FT-IR,and X-ray(for eleven examples)techniques and their thermal stability was verified(TGA).Additionally,we revealed unusual intramolecular homocoupling product formation during the silylative coupling reaction of vinyl-DDSQ derivatives.It deserves to be emphasized that these findings are the first example of a thorough investigation of hydrolytic condensation and the silylative coupling procedures in the chemistry of DDSQs.展开更多
In this work,we report the preparation,isolation,and characterization of a family of double-decker silses-quioxane architectures starting from the previously reported DDSQ-Me2H2precursor,a mixture of cis and tra...In this work,we report the preparation,isolation,and characterization of a family of double-decker silses-quioxane architectures starting from the previously reported DDSQ-Me2H2precursor,a mixture of cis and trans isomers.Using such a starting material results in a subsequent mixture of isomers when hydrosilyl-ation reactions using DDSQ-Me2H2and hydroxyalkyl-substituted alkenes catalyzed by Karstedt catalyst are performed.We describe a procedure to sequentially crystallize the two isomers from one another,affording a protocol potentially applicable to other closely related derivatives.The ability to access pure cis and trans isomers of double-decker silsesquioxanes may result in the preparation of new materials and polymers with well-defined properties.All resulting silsesquioxanes were characterized by multinuclear(1H,13C,and29Si)NMR spectroscopy,FT-IR,and HR-MS.Additionally,we report five crystal structures of geometrical isomers,including two cis forms described in the literature for the first time.This is a break-through in itself and sets a new strategy for obtaining such exiting organosilicon-based systems.展开更多
Designed and built by eight Dutch engineers,the worlds longest bicycle is 55.16 meters,roughly the same length as four double-decker buses.39-year-old Ivan Schalk had been thinking about building the world's longe...Designed and built by eight Dutch engineers,the worlds longest bicycle is 55.16 meters,roughly the same length as four double-decker buses.39-year-old Ivan Schalk had been thinking about building the world's longest bicycle since reading about it in The Guinness Book of Records when he was a child,but he only started this project in 2018,as a way to fill up his free time.展开更多
In an active magnetic bearing(AMB)system,the catcher bearings(CBs)are indispensable to protect the rotor and stator in case the magnetic bearings fail or overload.A new CB structure composed of two ball bearings is in...In an active magnetic bearing(AMB)system,the catcher bearings(CBs)are indispensable to protect the rotor and stator in case the magnetic bearings fail or overload.A new CB structure composed of two ball bearings is introduced.Detailed simulation models containing contact model between rotor and inner race,double-decker catcher bearing(DDCB)model as well as single-decker catcher bearing(SDCB)model are established using multibody dynamics simulation software MSC.ADAMS.Then,using those established models,the rotor orbits and the contact forces between rotor and inner race are simulated respectively after rotor drop on DDCBs and SDCBs.The simulation result shows that the rotor vibration range using DDCBs is significantly smaller than that using SDCBs;the maximum contact forces drop about 15%—27% compared with the contact forces using SDCBs.Finally,the test bench for the rotor drop experiments is built and the rotor drop experiments for different types of CBs are carried out.Labview data acquisition system is utilized to collect the displacement of rotor and the rotating frequencies of both inner race and intermediate races after rotor drop.The experimental results are comparatively analyzed,and the conclusion that DDCB can help to reduce vibration amplitude and collision force is obtained.The studies can provide certain theoretical and experimental references for the application of DDCBs in AMB system.展开更多
摘要Poly (4- methylphenoxyphosphnzene ) -graft-poly ( ethylene oxide ) ( PPZ-g- PEO ), a novel amphiphilie grafting polymer was prepared via the Decker-Forster reaction. It is found that the graft efficiency increased with extension of reaction time. Low molecular weight of poly ( ethylene oxide ) favored the grafting reaction. The grafted polymer has two different glass transition temperatures( Tg) with those of pure poly( 4-methyl- phenoxy-phopsphazene ) and PEO. The emulsifying ability of grafted polymer was studied with benzene-water mixtare. The emulsifying volumes increased with the decreasing of PEO' s molecular weight. The contact angle of film forming from grafted polymer decreased after introduction of PEO grafting chain.
基金Financial support from the Natural Science Foundation of China,National Key Basic Research Program of China(grant no.2013CB933402 and 2012CB224801)National Ministry of Education of China,and Beijing Municipal Commission of Education is gratefully acknowledged.
摘要Two new chiral mixed(phthalocyaninato)(porphyrinato)rare earth triple-decker complexes with both(R)-and(S)-enantiomers were synthesized and structurally characterized.The significant magneto-chiral cross effect revealed for the dysprosium compound suggests the great potential of sandwich-type tetrapyrrole rare earth systems in the research field of magneto-chiral dichroism.
基金the Anyang Key Laboratory for Chemical Biosensing(21302003)the Natural Science Foundation of China(21471015,21631003,and 21701046)the Fundamental Research Funds for the Central Universities(FRF-BD-17-016A)is gratefully acknowledged.
摘要Mixed(phthalocyaninato)(porphyrinato)rare earth double-decker complexes MIII(Pc)(TNP)(M=Tb(1),Dy(2),and Y(3);Pc=phthalocyaninate;TNP=tetranaphthylporphyrinate)were synthesized and characterized by elemental analysis and a range of spectroscopic methods.They represent the first examples of double-decker rare earth complexes containing a tetranaphthylporphyrin ligand.
基金Financial support from National Natural Science Foundation of China(No.21401009,21631003,21671017,and 21671024)Fundamental Research Funds for the Central Universities(No.FRF-BD-17-016A)Beijing Municipal Commission of Education,and University of Science and Technology Beijing is gratefully acknowledged.
摘要For the purpose of engineering magnetic anisotropy,chiral binaphthyl substituents with slight electron-withdrawing ability and dibutylamino substituents with intense electron-donating nature are incoporated onto the periphery of each phthalocyanine ligand in the bis(phthalocyaninato)terbium double-decker compound,resulting in the chiral heteroleptic bis(phthalocyaninato)terbium complex(R)/(S)-[Pc(OBNP)4]Tb{Pc[N(C4H9)2]8}(R/S-1){Pc(OBNP)4={tetrakis(dinaphtho[1,2-e:1′,2′-g]-1,4-dioxocine)[2,3-b;2′,3′-k;2″,3″-t;2″′,3″′-c′]phthalocyanine};Pc[N(C4H9)2]8=[2,3,9,10,16,17,23,24-octakis(dibutylamino)phthalocyanine]}.Magnetic studies reveal the typical single-ion magnet(SIM)nature of this chiral bis(phthalocyaninato)terbium double-decker with spin reversal energy barrier of 638 K.A butterfly-shaped magnetic hysteresis loop was observed at even 25 K for R-1 under the sweep rate of 500 Oe s-1.The performance of this SIM is well rationalized on the basis of theoretical analysis of the electrostatic potential according to calculations using the density functional theory method.
基金supported by the National Science Centre(Poland)Project OPUS UMO 2016/23/B/ST5/00201 and grant no.POWR.03.02.00-00-I026/16 co-financed by the European Union through the European Social Fund under the Operational Program Knowledge Education Development.
摘要Despite the rapid progress in the research on the synthesis of linear macromolecular systems with double-decker SQs included in the co-polymer chain,based on diverse catalytic processes,it still has limitations because of the formation of co-oligomers up to 20 units in a chain.Herein,we present a distinct look at known hydrosilylation reactions for forming hybrid copolymers.
基金funded by the National Science Centre(NCN)grant no UMO-2016/23/B/ST5/00201,UMO-2017/27/N/ST5/00175,and UMO-2020/36/T/ST5/00072 and grants no.POWR.03.02.00-00-I023/17 and POWR.03.02.00-00-I026/16 cofinanced by the European Union through the European Social Fund under the Operational Program Knowledge Education Development.
摘要Herein,we disclose an unexpected Si–O–Si cage reorganization that was observed during the standard hydrolytic condensation procedure of tetrasilanol double-decker silsesquioxane(DDSQ)with respective mono-and di-chlorosilanes.The investigation of this process allowed us to propose the possible mechanism of this transformation.The formation of all structures was confirmed by NMR,FT-IR,and X-ray(for eleven examples)techniques and their thermal stability was verified(TGA).Additionally,we revealed unusual intramolecular homocoupling product formation during the silylative coupling reaction of vinyl-DDSQ derivatives.It deserves to be emphasized that these findings are the first example of a thorough investigation of hydrolytic condensation and the silylative coupling procedures in the chemistry of DDSQs.
基金supported by the National Science Centre,Poland(Grant No.2020/39/B/ST4/00910).
摘要In this work,we report the preparation,isolation,and characterization of a family of double-decker silses-quioxane architectures starting from the previously reported DDSQ-Me2H2precursor,a mixture of cis and trans isomers.Using such a starting material results in a subsequent mixture of isomers when hydrosilyl-ation reactions using DDSQ-Me2H2and hydroxyalkyl-substituted alkenes catalyzed by Karstedt catalyst are performed.We describe a procedure to sequentially crystallize the two isomers from one another,affording a protocol potentially applicable to other closely related derivatives.The ability to access pure cis and trans isomers of double-decker silsesquioxanes may result in the preparation of new materials and polymers with well-defined properties.All resulting silsesquioxanes were characterized by multinuclear(1H,13C,and29Si)NMR spectroscopy,FT-IR,and HR-MS.Additionally,we report five crystal structures of geometrical isomers,including two cis forms described in the literature for the first time.This is a break-through in itself and sets a new strategy for obtaining such exiting organosilicon-based systems.
摘要Designed and built by eight Dutch engineers,the worlds longest bicycle is 55.16 meters,roughly the same length as four double-decker buses.39-year-old Ivan Schalk had been thinking about building the world's longest bicycle since reading about it in The Guinness Book of Records when he was a child,but he only started this project in 2018,as a way to fill up his free time.
基金Supported by the National Natural Science Foundation of China(51205186)the National Science Foundation for Post-doctoral Scientists of China(2012M511264)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20123218120024)
摘要In an active magnetic bearing(AMB)system,the catcher bearings(CBs)are indispensable to protect the rotor and stator in case the magnetic bearings fail or overload.A new CB structure composed of two ball bearings is introduced.Detailed simulation models containing contact model between rotor and inner race,double-decker catcher bearing(DDCB)model as well as single-decker catcher bearing(SDCB)model are established using multibody dynamics simulation software MSC.ADAMS.Then,using those established models,the rotor orbits and the contact forces between rotor and inner race are simulated respectively after rotor drop on DDCBs and SDCBs.The simulation result shows that the rotor vibration range using DDCBs is significantly smaller than that using SDCBs;the maximum contact forces drop about 15%—27% compared with the contact forces using SDCBs.Finally,the test bench for the rotor drop experiments is built and the rotor drop experiments for different types of CBs are carried out.Labview data acquisition system is utilized to collect the displacement of rotor and the rotating frequencies of both inner race and intermediate races after rotor drop.The experimental results are comparatively analyzed,and the conclusion that DDCB can help to reduce vibration amplitude and collision force is obtained.The studies can provide certain theoretical and experimental references for the application of DDCBs in AMB system.