Selenium was inserted into the zinc carbon bond of aryl zinc halides to form corresponding zinc selenoates. They reacted in THF-HMPA with acylhalides to afford the selenoesters in high yields.
Ti-containing carbon films were deposited by using magnetron sputtering deposition. The composition and microstructure of the carbon films were characterized in detail by combining the techniques of Rutherford backsca...Ti-containing carbon films were deposited by using magnetron sputtering deposition. The composition and microstructure of the carbon films were characterized in detail by combining the techniques of Rutherford backscattering spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It is found that carbon films contain Ti 18 at pct; after Ti incorporation, the films consist of titanium carbide; C1s peak appears at 283.4 eV and it could be divided into 283.29 and 284.55 eV, representing sp2 and sp3, respectively, and sp2 is superior to sp3. This Ti-containing film with dominating sp2 bonds is nanocomposites with nanocrystalline TiC clusters embedded in an amorphous carbon matrix, which could be proved by XRD and TEM.展开更多
A new type of Cope rearrangement involving carbon-carbon bond cleavage (or de-tbutylation) was found during the heating of 4-allyl-4-methyl-2, 6-di-t-butylsemiquinone,
a-C:F films are deposited by microwave electron cyclotron resonance (ECR)plasma chemical vapor deposition (CVD) using trifluoromethane (CHF3) and benzene (C6H6) as source gases at different microwave powers. The radic...a-C:F films are deposited by microwave electron cyclotron resonance (ECR)plasma chemical vapor deposition (CVD) using trifluoromethane (CHF3) and benzene (C6H6) as source gases at different microwave powers. The radicals in plasma originating from source gases dissociation are analyzed by relative irradiance measurement. The bonding configurations and binding state of a-C:F films are measured with Fourier-transformed infrared spectrometer (FTIR) and x-ray photoelectron spectroscopy (XPS). The results show that a-C:F films are mainly composed of CF radical at lower powers but of CF2 radical at higher powers. The deposition of films is related to the radicals generated in plasma and the main bonding configurations are dependent on the ratio of CF to CF2 radicals in films.展开更多
New carbon bonded filters with “active and reactive coatings ” for higher filtration efficiency of alumina based inclusions as well as nano-engineered filters with nano-scaled additives are explored with the aid of ...New carbon bonded filters with “active and reactive coatings ” for higher filtration efficiency of alumina based inclusions as well as nano-engineered filters with nano-scaled additives are explored with the aid of impingement tests and are evaluated according to their cold crushing strengths at room temperature. The combination of carbon nanotubes and alumina nanosheets additives leads to in situ formation of Al3 CON. Both the nanoscaled additives as well as the extra alumina “active”coating lead to improved mechanical performance of the carbon bonded filters and open the horizon for filter macrostructures with higher filtration capacities in means of bigger dimensions. In a further step MWCNT( multi walled carbon nanotubes) in combination with a synthetic pitch have been used as a functional coating on the surface of alumina carbon bonded filters. These filters have then been evaluated also with uncoated filters in a special casting simulator and the interactions between steel and filtering material have been investigated.展开更多
Polymeric nanoparticles(NPs)have drawn great interest in the past few years due to their potential applications in the felds of biomedical and optical technologies.However,it is still a challenge to prepare function...Polymeric nanoparticles(NPs)have drawn great interest in the past few years due to their potential applications in the felds of biomedical and optical technologies.However,it is still a challenge to prepare functional polymeric NPs,especially for particle diameters smaller than 50 nm.In this work,we demonstrate a one-pot method to fabricate reactive poly(divinyl benzene-co-maleic anhydride)NPs(PDVBMAH NPs)through a self-stable precipitation polymerization process.The size and morphology of these PDVBMAH NPs were characterized in detail by scanning electronic microscopy,and their chemical structure was determined by IR.The results showed that these NPs were highly cross-linked and their diameter was about 30 nm with narrow distribution.Additionally,the DVB and MAH endow the NPs with reactive surface anhydride and pendant vinyl groups,and these particles could be further functionalized through reaction of these groups.A plausible pathway was proposed for the formation of PDVBMAH NPs.展开更多
Halogenation of N-cinnamylbenzamides and N-[(2H-chromen-3-yl)methyl]benzamides using electrophilic halogen source was reported.Various halogenated dihydro-1,3-oxazine derivatives(45 examples)were synthesized in high t...Halogenation of N-cinnamylbenzamides and N-[(2H-chromen-3-yl)methyl]benzamides using electrophilic halogen source was reported.Various halogenated dihydro-1,3-oxazine derivatives(45 examples)were synthesized in high to excellent yields(up to 98%yields),as well as halogenated dihydrochromeno-1,3-oxazine derivatives(56 examples,up to 96%yields).The properties of mild conditions,metal-free and high efficiency of the reaction made it a promising strategy in future applications for the construction of carbon-halogen(fluorine,F;chlorine,Cl;bromine,Br;iodine,I)bond and 1,3-oxazine derivatives.展开更多
文摘Selenium was inserted into the zinc carbon bond of aryl zinc halides to form corresponding zinc selenoates. They reacted in THF-HMPA with acylhalides to afford the selenoesters in high yields.
文摘Ti-containing carbon films were deposited by using magnetron sputtering deposition. The composition and microstructure of the carbon films were characterized in detail by combining the techniques of Rutherford backscattering spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It is found that carbon films contain Ti 18 at pct; after Ti incorporation, the films consist of titanium carbide; C1s peak appears at 283.4 eV and it could be divided into 283.29 and 284.55 eV, representing sp2 and sp3, respectively, and sp2 is superior to sp3. This Ti-containing film with dominating sp2 bonds is nanocomposites with nanocrystalline TiC clusters embedded in an amorphous carbon matrix, which could be proved by XRD and TEM.
文摘A new type of Cope rearrangement involving carbon-carbon bond cleavage (or de-tbutylation) was found during the heating of 4-allyl-4-methyl-2, 6-di-t-butylsemiquinone,
文摘a-C:F films are deposited by microwave electron cyclotron resonance (ECR)plasma chemical vapor deposition (CVD) using trifluoromethane (CHF3) and benzene (C6H6) as source gases at different microwave powers. The radicals in plasma originating from source gases dissociation are analyzed by relative irradiance measurement. The bonding configurations and binding state of a-C:F films are measured with Fourier-transformed infrared spectrometer (FTIR) and x-ray photoelectron spectroscopy (XPS). The results show that a-C:F films are mainly composed of CF radical at lower powers but of CF2 radical at higher powers. The deposition of films is related to the radicals generated in plasma and the main bonding configurations are dependent on the ratio of CF to CF2 radicals in films.
基金financially supported by the German Research Foundation ( DFG ) in frame of the Collaborative Research Center 920
文摘New carbon bonded filters with “active and reactive coatings ” for higher filtration efficiency of alumina based inclusions as well as nano-engineered filters with nano-scaled additives are explored with the aid of impingement tests and are evaluated according to their cold crushing strengths at room temperature. The combination of carbon nanotubes and alumina nanosheets additives leads to in situ formation of Al3 CON. Both the nanoscaled additives as well as the extra alumina “active”coating lead to improved mechanical performance of the carbon bonded filters and open the horizon for filter macrostructures with higher filtration capacities in means of bigger dimensions. In a further step MWCNT( multi walled carbon nanotubes) in combination with a synthetic pitch have been used as a functional coating on the surface of alumina carbon bonded filters. These filters have then been evaluated also with uncoated filters in a special casting simulator and the interactions between steel and filtering material have been investigated.
文摘Polymeric nanoparticles(NPs)have drawn great interest in the past few years due to their potential applications in the felds of biomedical and optical technologies.However,it is still a challenge to prepare functional polymeric NPs,especially for particle diameters smaller than 50 nm.In this work,we demonstrate a one-pot method to fabricate reactive poly(divinyl benzene-co-maleic anhydride)NPs(PDVBMAH NPs)through a self-stable precipitation polymerization process.The size and morphology of these PDVBMAH NPs were characterized in detail by scanning electronic microscopy,and their chemical structure was determined by IR.The results showed that these NPs were highly cross-linked and their diameter was about 30 nm with narrow distribution.Additionally,the DVB and MAH endow the NPs with reactive surface anhydride and pendant vinyl groups,and these particles could be further functionalized through reaction of these groups.A plausible pathway was proposed for the formation of PDVBMAH NPs.
基金supported by the National Natural Science Foundation of China(No.22108264).
文摘Halogenation of N-cinnamylbenzamides and N-[(2H-chromen-3-yl)methyl]benzamides using electrophilic halogen source was reported.Various halogenated dihydro-1,3-oxazine derivatives(45 examples)were synthesized in high to excellent yields(up to 98%yields),as well as halogenated dihydrochromeno-1,3-oxazine derivatives(56 examples,up to 96%yields).The properties of mild conditions,metal-free and high efficiency of the reaction made it a promising strategy in future applications for the construction of carbon-halogen(fluorine,F;chlorine,Cl;bromine,Br;iodine,I)bond and 1,3-oxazine derivatives.