The selective brominations of 3, 4-dimethoxytoluene with N-bromosuccinimide were reported. The nuclear and side-chain brominated products were obtained under different reaction conditions. The mechanism was also discu...The selective brominations of 3, 4-dimethoxytoluene with N-bromosuccinimide were reported. The nuclear and side-chain brominated products were obtained under different reaction conditions. The mechanism was also discussed.展开更多
Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters ...Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters are determined by the five-level model, which is adopted to interpret the experimental data. The change of refraction index per unit density of the excited state obtained by a numerically simulation is a critical factor to determine the nonlinear behaviour of C70 in picosecond time regime.展开更多
Abstract--Poly4-vinylphenol （P4VP）/multi-wan carbon nanotubes （MWNTs） multi-layer sensitive films were deposited on interdigitated electrodes by airbrush technology to detect toluene vapor at room temperature. The...Abstract--Poly4-vinylphenol （P4VP）/multi-wan carbon nanotubes （MWNTs） multi-layer sensitive films were deposited on interdigitated electrodes by airbrush technology to detect toluene vapor at room temperature. The surface and section morphologies of the multi-layer films were observed by a scanning electron microscope （SEM）. It is found that the resistance of the sensor increases when it is exposed to toluene vapor and the response has a good linearity with the concentration of toluene. The results show that the P4VP/MWNTs three-layer film sensors have better sensing properties compared with the two-layer film sensors. The related sensing mechanism is studied in detail.展开更多
Zeolites NaY and Ce（IV）Y were employed as adsorbents to remove organic sulfur compounds from model gasoline （MG） solutions with and without toluene in static adsorption experiments at room temperature （RT） and a...Zeolites NaY and Ce（IV）Y were employed as adsorbents to remove organic sulfur compounds from model gasoline （MG） solutions with and without toluene in static adsorption experiments at room temperature （RT） and atmospheric pressure. The adsorbents were characterized by XRD, XRF and pyridine infrared spectrum （IR）. The adsorption experiments show that the desulfurization performance of Ce（IV）Y is much better than that of NaY. The sulfur removal over both NaY and Ce（IV）Y decreases with the increase of toluene concentration in MG, however, the decline tendency on Ce（IV）Y is smooth, and it is steep on NaY. FT-IR spectra of thiophene adsorption indicate that thiophene molecules are mainly adsorbed on NaY via π electron interaction, but on Ce（IV）Y, in addition to the π electron interaction, both Ce^4＋-S direct interaction and protonation of thiophene also play important roles. Toluene molecules are adsorbed on NaY also via π electron interaction. Although the amount of Bronsted acid sites is increased due to the introduction of Ce^4＋ ions into NaY zeolite, it is not found to influence the adsorption mode of toluene over Ce（IV）Y. Compared with NaY zeolite, the improved desulfurization performance over Ce（IV）Y for removing organic sulfur compounds from MG solution, especially those containing large amount of aromatics, may be ascribed to the direct Ce（IV）-S interaction, which is much resistant to the influence resulted from toluene adsorption.展开更多
Co-based catalysts are the most promising catalysts in catalytic oxidation of volatile organic compounds(VOCs).Precious metal doping is adopted to improve the catalytic activity of toluene on Co_(3)O_(4) catalysts,but...Co-based catalysts are the most promising catalysts in catalytic oxidation of volatile organic compounds(VOCs).Precious metal doping is adopted to improve the catalytic activity of toluene on Co_(3)O_(4) catalysts,but greatly increases its cost along with it.It is found that doping a small amount of rare earth(Ce,Pr,Sm and Nd)can dramatically promote the catalytic activity of Co_(3)O_(4).Especially,the Nd-doped Co_(3)O_(4) catalyst exhibits excellent catalytic activity with a toluene removal rate of 90% at 162.1℃,which is even better than that of Pt-doped Co_(3)O_(4).Compared with other rare earth metal doping,the Nd doping leads to a higher ratio of Co^(3+)/Co^(2+) and has more oxygen vacancies.The in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)experiments show that the lattice oxygen of Nd-Co sample can be utilized at a quite low temperature,while that of pure Co_(3)O_(4) cannot engage in oxidation reaction when the temperature is below 200℃,which visually demonstrates the main reason for the improved catalytic performance of Nd-Co catalyst.展开更多
A serials of novel 5-substituted benzyl-2,4-diamino pyrimidine derivatives have been synthesized and evaluated as inhibitors of c-Fms kinase by the standard MTT method.The results showed that compound 15,5-[3-methoxy...A serials of novel 5-substituted benzyl-2,4-diamino pyrimidine derivatives have been synthesized and evaluated as inhibitors of c-Fms kinase by the standard MTT method.The results showed that compound 15,5-[3-methoxy-4-（pyridine-3-yl）benzyl]-2,4-diamino pyrimidine,had an IC50 of 1.45μmol/L in inhibiting the proliferation of M-CSF-dependent myeloid leukemia cells in mice （NFS-60）,which was similar with GW2580,a selective inhibitor of c-Fms kinase.展开更多
Mesoporous transition metal oxide catalysts are well-used in the elimination of volatile organic compounds.In this study,we developed an efficient method for the preparation of mesoporous-Mn_(3)O_(4)(mMn_(3)O_(4))with...Mesoporous transition metal oxide catalysts are well-used in the elimination of volatile organic compounds.In this study,we developed an efficient method for the preparation of mesoporous-Mn_(3)O_(4)(mMn_(3)O_(4))without the use of templates or surfactants.In this method,KCl protects oxygen defects on the surface of fresh Mn_(3)O_(4) crystallites.m-Mn_(3)O_(4) shows higher ameliorative catalytic activity than bulk-Mn_(3)O_(4)(b-Mn_(3)O_(4)) and calcined-Mn_(3)O_(4)(c-Mn_(3)O_(4)),achieving toluene catalytic oxidation of T_(10) and T_(90)(the temperature at a conversion rate of about 10%and 90%)at 191℃and 230℃,respectively(WHSV=40,000 ml·g^(-1)·h^(-1)).Based on various characterizations,the prepared m-Mn_(3)O_(4)has large specific surface area and abundant oxygen defects,and thus can provide more surface active sites,which give it superior toluene combustion activity.展开更多
文摘The selective brominations of 3, 4-dimethoxytoluene with N-bromosuccinimide were reported. The nuclear and side-chain brominated products were obtained under different reaction conditions. The mechanism was also discussed.
基金Project supported by the National Natural Science Fundation of China(Grant No.90922007)
文摘Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters are determined by the five-level model, which is adopted to interpret the experimental data. The change of refraction index per unit density of the excited state obtained by a numerically simulation is a critical factor to determine the nonlinear behaviour of C70 in picosecond time regime.
基金partially supported by the National Natural Foundation of China under Grant No.61176066 and No.61101031
文摘Abstract--Poly4-vinylphenol （P4VP）/multi-wan carbon nanotubes （MWNTs） multi-layer sensitive films were deposited on interdigitated electrodes by airbrush technology to detect toluene vapor at room temperature. The surface and section morphologies of the multi-layer films were observed by a scanning electron microscope （SEM）. It is found that the resistance of the sensor increases when it is exposed to toluene vapor and the response has a good linearity with the concentration of toluene. The results show that the P4VP/MWNTs three-layer film sensors have better sensing properties compared with the two-layer film sensors. The related sensing mechanism is studied in detail.
基金supported by the Fundamental Research Funds for the Key Universities (Grant No. DUT10LK25)the National Natural Science Foundation of China (Grant No. 21106014)
文摘Zeolites NaY and Ce（IV）Y were employed as adsorbents to remove organic sulfur compounds from model gasoline （MG） solutions with and without toluene in static adsorption experiments at room temperature （RT） and atmospheric pressure. The adsorbents were characterized by XRD, XRF and pyridine infrared spectrum （IR）. The adsorption experiments show that the desulfurization performance of Ce（IV）Y is much better than that of NaY. The sulfur removal over both NaY and Ce（IV）Y decreases with the increase of toluene concentration in MG, however, the decline tendency on Ce（IV）Y is smooth, and it is steep on NaY. FT-IR spectra of thiophene adsorption indicate that thiophene molecules are mainly adsorbed on NaY via π electron interaction, but on Ce（IV）Y, in addition to the π electron interaction, both Ce^4＋-S direct interaction and protonation of thiophene also play important roles. Toluene molecules are adsorbed on NaY also via π electron interaction. Although the amount of Bronsted acid sites is increased due to the introduction of Ce^4＋ ions into NaY zeolite, it is not found to influence the adsorption mode of toluene over Ce（IV）Y. Compared with NaY zeolite, the improved desulfurization performance over Ce（IV）Y for removing organic sulfur compounds from MG solution, especially those containing large amount of aromatics, may be ascribed to the direct Ce（IV）-S interaction, which is much resistant to the influence resulted from toluene adsorption.
基金Project supported by the Sichuan Provincial Science and Technology Agency Support Projects(2020YFG0066)Young Talent Team Science and Technology Innovation Project of Sichuan Province(2020JDTD0005)。
文摘Co-based catalysts are the most promising catalysts in catalytic oxidation of volatile organic compounds(VOCs).Precious metal doping is adopted to improve the catalytic activity of toluene on Co_(3)O_(4) catalysts,but greatly increases its cost along with it.It is found that doping a small amount of rare earth(Ce,Pr,Sm and Nd)can dramatically promote the catalytic activity of Co_(3)O_(4).Especially,the Nd-doped Co_(3)O_(4) catalyst exhibits excellent catalytic activity with a toluene removal rate of 90% at 162.1℃,which is even better than that of Pt-doped Co_(3)O_(4).Compared with other rare earth metal doping,the Nd doping leads to a higher ratio of Co^(3+)/Co^(2+) and has more oxygen vacancies.The in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)experiments show that the lattice oxygen of Nd-Co sample can be utilized at a quite low temperature,while that of pure Co_(3)O_(4) cannot engage in oxidation reaction when the temperature is below 200℃,which visually demonstrates the main reason for the improved catalytic performance of Nd-Co catalyst.
基金financially supported by the National High-Tech Research and Development Program of China(863 Program)(No.2006AA10A201)National Natural Science Foundation(No.30472093)
文摘A serials of novel 5-substituted benzyl-2,4-diamino pyrimidine derivatives have been synthesized and evaluated as inhibitors of c-Fms kinase by the standard MTT method.The results showed that compound 15,5-[3-methoxy-4-（pyridine-3-yl）benzyl]-2,4-diamino pyrimidine,had an IC50 of 1.45μmol/L in inhibiting the proliferation of M-CSF-dependent myeloid leukemia cells in mice （NFS-60）,which was similar with GW2580,a selective inhibitor of c-Fms kinase.
基金supported by the National Natural Science Foundation of China(Nos.21306026,21576054)Natural Science Foundation of Guangdong Province(No.2018A030310563)the Foundation of Higher Education of Guangdong Province(2018KZDXM031)。
文摘Mesoporous transition metal oxide catalysts are well-used in the elimination of volatile organic compounds.In this study,we developed an efficient method for the preparation of mesoporous-Mn_(3)O_(4)(mMn_(3)O_(4))without the use of templates or surfactants.In this method,KCl protects oxygen defects on the surface of fresh Mn_(3)O_(4) crystallites.m-Mn_(3)O_(4) shows higher ameliorative catalytic activity than bulk-Mn_(3)O_(4)(b-Mn_(3)O_(4)) and calcined-Mn_(3)O_(4)(c-Mn_(3)O_(4)),achieving toluene catalytic oxidation of T_(10) and T_(90)(the temperature at a conversion rate of about 10%and 90%)at 191℃and 230℃,respectively(WHSV=40,000 ml·g^(-1)·h^(-1)).Based on various characterizations,the prepared m-Mn_(3)O_(4)has large specific surface area and abundant oxygen defects,and thus can provide more surface active sites,which give it superior toluene combustion activity.
