In this study,cyclohexene was used as a representative of olefin and catalyzed by CeY zeolites in a fixedbed reactor under mild conditions,and the influence of Ce species in hydride transfer reaction over CeY zeolites...In this study,cyclohexene was used as a representative of olefin and catalyzed by CeY zeolites in a fixedbed reactor under mild conditions,and the influence of Ce species in hydride transfer reaction over CeY zeolites was evaluated.CeY zeolites show more excellent hydride transfer properties than HY zeolite.Based on the results of almost identical Bronsted acid properties but not the product distributions for 0.075 CeY and 0.075 CeY(DC)samples,it should be suggested that the Bronsted acid strength and density are not the deciding factors to the hydride transfer reaction.A unique band at 1442 cm^-1 in situ FTIR spectroscopy spectra are assigned to pyridine complexes bonded to a class of active Ce species that could reversibly migrate from the core of SOD cages to its 6-rings mouth towards the supercages.These results provide valuable information that these active Ce species should play a synergistic role with the Bronsted acid sites in enhancing the hydride transfer reaction with a bimolecular mechanism over CeY zeolites.展开更多
A waveguide optical isolator with a CeY2Fe5O12 guiding layer employing a nonreciprocal phase shift was studied. The isolation ratio of more than 12.2 dB was achieved at a wavelength of 1.55μm.
Na-Se batteries have caught tremendous attention because of natural abundant of element sodium and their high volumetric energy density(2530 Wh/L).However,the low utilization ratio of Se is the main obstacle for pract...Na-Se batteries have caught tremendous attention because of natural abundant of element sodium and their high volumetric energy density(2530 Wh/L).However,the low utilization ratio of Se is the main obstacle for practical application.Herein,an advanced Se-based electrode is designed and prepared by using tea stem-derived micropore carbon matrix(TSC)as Se host and coating TSC/Se with cyclic polyacrylonitrile(cPAN).TSC/Se/cPAN electrode shows rate capacity of 318.3 mAh/g at 2 C(1 C=675 mA/g)and great discharge capacity of 420.6 mAh/g after 300 cycles at 0.2 C.The impressive electrochemical performance is mainly ascribed to the interface design of c PAN coating,resulting in the enhanced electronic conductivity of whole electrode and high ratio of robust inorganic salt NaCl in CEI film.The TSC/Se/c PAN||NVP full cell also exhibits great discharge capacity of 556.6 mAh/g after 55 cycles at 0.1 C.展开更多
基金Project supported by the National Natural Science Foundation of China(21902068,U1662135)PetroChina Company Limited(KYWX-18-011)Scientific Research Project of Education Department of Liaoning Province(L2019035)。
文摘In this study,cyclohexene was used as a representative of olefin and catalyzed by CeY zeolites in a fixedbed reactor under mild conditions,and the influence of Ce species in hydride transfer reaction over CeY zeolites was evaluated.CeY zeolites show more excellent hydride transfer properties than HY zeolite.Based on the results of almost identical Bronsted acid properties but not the product distributions for 0.075 CeY and 0.075 CeY(DC)samples,it should be suggested that the Bronsted acid strength and density are not the deciding factors to the hydride transfer reaction.A unique band at 1442 cm^-1 in situ FTIR spectroscopy spectra are assigned to pyridine complexes bonded to a class of active Ce species that could reversibly migrate from the core of SOD cages to its 6-rings mouth towards the supercages.These results provide valuable information that these active Ce species should play a synergistic role with the Bronsted acid sites in enhancing the hydride transfer reaction with a bimolecular mechanism over CeY zeolites.
文摘A waveguide optical isolator with a CeY2Fe5O12 guiding layer employing a nonreciprocal phase shift was studied. The isolation ratio of more than 12.2 dB was achieved at a wavelength of 1.55μm.
基金financially supported by Fujian Science and Technology Planning Projects of China(Nos.2022T3067 and 2023H0045)the Self-deployment Project Research Programs of Haixi Institutes,Chinese Academy of Sciences(No.CXZX2022-JQ12)the XIREM autonomously deployment project(No.2023GG02)。
文摘Na-Se batteries have caught tremendous attention because of natural abundant of element sodium and their high volumetric energy density(2530 Wh/L).However,the low utilization ratio of Se is the main obstacle for practical application.Herein,an advanced Se-based electrode is designed and prepared by using tea stem-derived micropore carbon matrix(TSC)as Se host and coating TSC/Se with cyclic polyacrylonitrile(cPAN).TSC/Se/cPAN electrode shows rate capacity of 318.3 mAh/g at 2 C(1 C=675 mA/g)and great discharge capacity of 420.6 mAh/g after 300 cycles at 0.2 C.The impressive electrochemical performance is mainly ascribed to the interface design of c PAN coating,resulting in the enhanced electronic conductivity of whole electrode and high ratio of robust inorganic salt NaCl in CEI film.The TSC/Se/c PAN||NVP full cell also exhibits great discharge capacity of 556.6 mAh/g after 55 cycles at 0.1 C.
