The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K～973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is s...The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K～973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is shown that molybdenum nitrid(Mo2N) was formed above 923K and its intermediate MoO2 formed at about 573～623K under the rapid (5K/min.) TPR conditions.Mo2N is the most active species for pyridine HDN among MoO3,MoO2,MoS2,and Mo2N. Moreover,it can be promoted by adding Ni component.It is shown that the Ni/Mo2N catalyst prepared by adding some NiO into the precursor MoO3 has a steady HDN activity Which is far higher than that of the commercial sulfided NiMo/Al2O3(HR346) catalyst.展开更多
A new copper（Ⅱ） compound with imino nitroxide radicals [Cu（IM-MeImz）2].（SCN）2 （IM-meImz =2-（5-methylimidazol-4-yl）-4,4,5,5-tetramethyl-2-imidazoline- 1-oxyl） has been synthesized and characterized structura...A new copper（Ⅱ） compound with imino nitroxide radicals [Cu（IM-MeImz）2].（SCN）2 （IM-meImz =2-（5-methylimidazol-4-yl）-4,4,5,5-tetramethyl-2-imidazoline- 1-oxyl） has been synthesized and characterized structurally and magnetically. It crystallizes in monoclinic, space group P21/c with a = 9.3604（7）, b = 10.3012（7）, c = 16.6684（12）A, β = 105.0290（10）^o, V = 1552.25（19）A3, C24H34CUN10O2S2, Mr = 622.27, Z = 2, Dc = 1.331 g/cm^3,μ（MoKα） = 0.876 mm^-1, F（000） = 650, the final R = 0.0374 and wR = 0.1079. X-ray analysis demonstrates that the IM-MeImz ligand is coordinated to the copper（Ⅱ） ion as an unusual didentate chelate with a k-2 N（MeImz）,O（IM） mode in the complex. The square-planar coordination sites at Cu（Ⅱ） are occupied by two 0 and two N atoms from the imino nitroxide radicals. The complex molecules are connected as a onedimensional polymer structure by intermolecular interactions. Magnetic measurements show that there are intramolecular antiferromagnetic interactions between the Cu（Ⅱ） ion and radicals.展开更多
MoS_2-decorated C_3N_4(C_3N_4/MoS_2) nanosheets hybrid photocatalysts were prepared by a simple sonication-impregnation method. Face-to-face lamellar heterojunctions were well established between two dimension(2D) C_3...MoS_2-decorated C_3N_4(C_3N_4/MoS_2) nanosheets hybrid photocatalysts were prepared by a simple sonication-impregnation method. Face-to-face lamellar heterojunctions were well established between two dimension(2D) C_3N_4 and MoS_2 nanosheets. The effects of MoS_2 content on the light absorption, charge transfer and photocatalytic activity of the hybrid samples were investigated. Characterization results show that MoS_2 nanosheets are well anchored on the face of C_3N_4 nanosheets and the composites have well dispersed layered morphology. After loading with MoS_2, the light absorption of composites was much improved, especially in visible-light region. The photocatalytic activities of C_3N_4/MoS_2 samples were evaluated based on the H_2 evolution under visible light irradiation(λ > 400 nm). When the loading amount of MoS_2 was increased to 5 wt%, the highest H_2 evolution rate(274 μmol·g^(-1)·h^(-1)) was obtained. Compared with samples obtained from direct impregnation method, sonication pretreatment is favorable for the formation of 2D layered heterojuctions and thus improve the photocatalytic activity. Slightly deactivation of C_3N_4/MoS_2 composites could be observed when recycled due to the mild photocorrosion of MoS_2. Based on the band alignments of C_3N_4 and MoS_2, a possible photocatalytic mechanism was discussed, where MoS_2 could efficiently promote the separation of the photogenerated carriers of C_3N_4.展开更多
The photocatalytic oxidation of gaseous chlorobenzene（CB） by the 365 nm-induced photocatalyst La/N–Ti O2, synthesized via a sol–gel and hydrothermal method, was evaluated. Response surface methodology（RSM） was u...The photocatalytic oxidation of gaseous chlorobenzene（CB） by the 365 nm-induced photocatalyst La/N–Ti O2, synthesized via a sol–gel and hydrothermal method, was evaluated. Response surface methodology（RSM） was used to model and optimize the conditions for synthesis of the photocatalyst. The optimal photocatalyst was 1.2La/0.5N–Ti O2（0.5） and the effects of La/N on crystalline structure, particle morphology, surface element content, and other structural characteristics were investigated by XRD（X-ray diffraction）, TEM（Transmission Electron Microscopy）, FTIR（Fourier transform infrared spectroscopy）, UV–vis（Ultraviolet–visible spectroscopy）, and BET（Brunauer Emmett Teller）. Greater surface area and smaller particle size were produced with the co-doped Ti O2 nanotubes than with reference Ti O2. The removal of CB was effective when performed using the synthesized photocatalyst,though it was less efficient at higher initial CB concentrations. Various modified Langmuir-Hinshelwood kinetic models involving the adsorption of chlorobenzene and water on different active sites were evaluated. Fitting results suggested that competitive adsorption caused by water molecules could not be neglected, especially for environments with high relative humidity. The reaction intermediates found after GC–MS（Gas chromatography–mass spectrometry） analysis indicated that most were soluble, low-toxicity, or both. The results demonstrated that the prepared photocatalyst had high activity for VOC（volatile organic compounds） conversion and may be used as a pretreatment prior to biopurification.展开更多
Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2 nodal involvement.Methods: A retrospective analysis of disease free survival and 5-year survival for NSC...Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2 nodal involvement.Methods: A retrospective analysis of disease free survival and 5-year survival for NSCLC patients who underwent primary surgical resection without neoadjuvant chemotherapy were performed.Between January 1998 and May 2004,133 patients were enrolled.Several factors such as age,sex,skip metastasis,number of N2 lymph node stations,type of resection,histology,adjuvant therapy etc.,were recorded and analyzed.SPSS 16.0 software was used.Results: Overall 5-year survival for 133 patients was 32.33%,5-year survival for single N2 station and multiple N2 stations sub-groups were 39.62% and 27.50% respectively,and 5-year survival for cN0–1 and cN2 sub-groups were 37.78% and 20.93% respectively.COX regression analysis revealed that number of N2 station (P = 0.013,OR: 0.490,95% CI: 0.427–0.781) and cN status (P = 0.009,OR: 0.607,95% CI: 0.372–0.992) were two favorable prognostic factors of survival.Conclusion: Number of N2 station and cN status were two favorable prognostic factors of survival.In restrict enrolled circumstances,after combined therapy made up of surgery and postoperative adjuvant therapy have been performed,satisfied survival could be achieved.展开更多
The Si3N4-based nanocomposites reinforced with micro ZrO2 and nano SiC particles were prepared by polarity dispersant and vacuum-sintering technology. The mechanical properties and microstructures were tested. The res...The Si3N4-based nanocomposites reinforced with micro ZrO2 and nano SiC particles were prepared by polarity dispersant and vacuum-sintering technology. The mechanical properties and microstructures were tested. The results show that appropriate amount of micro ZrO2 and nano SiC particles, not only enhance the microhardness, but also block the excessively growth of β-Si3N4 and β-Si3N4 grains, so they finally all grow up to uniformly pole-shaped grains. This process is similar to the strengthening and toughening mechanism of grain whiskers and makes a remarkable improvement on the toughness. Compared with Si3N4 ceramic, the toughness of Si3N4/SiC/ZrO2 nanocomposites are increased from 6.2 MPa·m1/2 to 11 MPa·m1/2.展开更多
文摘The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K～973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is shown that molybdenum nitrid(Mo2N) was formed above 923K and its intermediate MoO2 formed at about 573～623K under the rapid (5K/min.) TPR conditions.Mo2N is the most active species for pyridine HDN among MoO3,MoO2,MoS2,and Mo2N. Moreover,it can be promoted by adding Ni component.It is shown that the Ni/Mo2N catalyst prepared by adding some NiO into the precursor MoO3 has a steady HDN activity Which is far higher than that of the commercial sulfided NiMo/Al2O3(HR346) catalyst.
基金This work was supported by the N N S F of China (No. 20471026)the Natural Science Foundation of Henan Province (No. 0311021200)
文摘A new copper（Ⅱ） compound with imino nitroxide radicals [Cu（IM-MeImz）2].（SCN）2 （IM-meImz =2-（5-methylimidazol-4-yl）-4,4,5,5-tetramethyl-2-imidazoline- 1-oxyl） has been synthesized and characterized structurally and magnetically. It crystallizes in monoclinic, space group P21/c with a = 9.3604（7）, b = 10.3012（7）, c = 16.6684（12）A, β = 105.0290（10）^o, V = 1552.25（19）A3, C24H34CUN10O2S2, Mr = 622.27, Z = 2, Dc = 1.331 g/cm^3,μ（MoKα） = 0.876 mm^-1, F（000） = 650, the final R = 0.0374 and wR = 0.1079. X-ray analysis demonstrates that the IM-MeImz ligand is coordinated to the copper（Ⅱ） ion as an unusual didentate chelate with a k-2 N（MeImz）,O（IM） mode in the complex. The square-planar coordination sites at Cu（Ⅱ） are occupied by two 0 and two N atoms from the imino nitroxide radicals. The complex molecules are connected as a onedimensional polymer structure by intermolecular interactions. Magnetic measurements show that there are intramolecular antiferromagnetic interactions between the Cu（Ⅱ） ion and radicals.
基金Funded by the National Natural Science Foundation of China(No.21503096)
文摘MoS_2-decorated C_3N_4(C_3N_4/MoS_2) nanosheets hybrid photocatalysts were prepared by a simple sonication-impregnation method. Face-to-face lamellar heterojunctions were well established between two dimension(2D) C_3N_4 and MoS_2 nanosheets. The effects of MoS_2 content on the light absorption, charge transfer and photocatalytic activity of the hybrid samples were investigated. Characterization results show that MoS_2 nanosheets are well anchored on the face of C_3N_4 nanosheets and the composites have well dispersed layered morphology. After loading with MoS_2, the light absorption of composites was much improved, especially in visible-light region. The photocatalytic activities of C_3N_4/MoS_2 samples were evaluated based on the H_2 evolution under visible light irradiation(λ > 400 nm). When the loading amount of MoS_2 was increased to 5 wt%, the highest H_2 evolution rate(274 μmol·g^(-1)·h^(-1)) was obtained. Compared with samples obtained from direct impregnation method, sonication pretreatment is favorable for the formation of 2D layered heterojuctions and thus improve the photocatalytic activity. Slightly deactivation of C_3N_4/MoS_2 composites could be observed when recycled due to the mild photocorrosion of MoS_2. Based on the band alignments of C_3N_4 and MoS_2, a possible photocatalytic mechanism was discussed, where MoS_2 could efficiently promote the separation of the photogenerated carriers of C_3N_4.
基金supported by the National Natural Science Foundation of China(No.21276239)the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT13096)
文摘The photocatalytic oxidation of gaseous chlorobenzene（CB） by the 365 nm-induced photocatalyst La/N–Ti O2, synthesized via a sol–gel and hydrothermal method, was evaluated. Response surface methodology（RSM） was used to model and optimize the conditions for synthesis of the photocatalyst. The optimal photocatalyst was 1.2La/0.5N–Ti O2（0.5） and the effects of La/N on crystalline structure, particle morphology, surface element content, and other structural characteristics were investigated by XRD（X-ray diffraction）, TEM（Transmission Electron Microscopy）, FTIR（Fourier transform infrared spectroscopy）, UV–vis（Ultraviolet–visible spectroscopy）, and BET（Brunauer Emmett Teller）. Greater surface area and smaller particle size were produced with the co-doped Ti O2 nanotubes than with reference Ti O2. The removal of CB was effective when performed using the synthesized photocatalyst,though it was less efficient at higher initial CB concentrations. Various modified Langmuir-Hinshelwood kinetic models involving the adsorption of chlorobenzene and water on different active sites were evaluated. Fitting results suggested that competitive adsorption caused by water molecules could not be neglected, especially for environments with high relative humidity. The reaction intermediates found after GC–MS（Gas chromatography–mass spectrometry） analysis indicated that most were soluble, low-toxicity, or both. The results demonstrated that the prepared photocatalyst had high activity for VOC（volatile organic compounds） conversion and may be used as a pretreatment prior to biopurification.
文摘Objective: The aim of the study was to identify prognostic factors in non-small-cell lung cancer (NSCLC) with N2 nodal involvement.Methods: A retrospective analysis of disease free survival and 5-year survival for NSCLC patients who underwent primary surgical resection without neoadjuvant chemotherapy were performed.Between January 1998 and May 2004,133 patients were enrolled.Several factors such as age,sex,skip metastasis,number of N2 lymph node stations,type of resection,histology,adjuvant therapy etc.,were recorded and analyzed.SPSS 16.0 software was used.Results: Overall 5-year survival for 133 patients was 32.33%,5-year survival for single N2 station and multiple N2 stations sub-groups were 39.62% and 27.50% respectively,and 5-year survival for cN0–1 and cN2 sub-groups were 37.78% and 20.93% respectively.COX regression analysis revealed that number of N2 station (P = 0.013,OR: 0.490,95% CI: 0.427–0.781) and cN status (P = 0.009,OR: 0.607,95% CI: 0.372–0.992) were two favorable prognostic factors of survival.Conclusion: Number of N2 station and cN status were two favorable prognostic factors of survival.In restrict enrolled circumstances,after combined therapy made up of surgery and postoperative adjuvant therapy have been performed,satisfied survival could be achieved.
文摘The Si3N4-based nanocomposites reinforced with micro ZrO2 and nano SiC particles were prepared by polarity dispersant and vacuum-sintering technology. The mechanical properties and microstructures were tested. The results show that appropriate amount of micro ZrO2 and nano SiC particles, not only enhance the microhardness, but also block the excessively growth of β-Si3N4 and β-Si3N4 grains, so they finally all grow up to uniformly pole-shaped grains. This process is similar to the strengthening and toughening mechanism of grain whiskers and makes a remarkable improvement on the toughness. Compared with Si3N4 ceramic, the toughness of Si3N4/SiC/ZrO2 nanocomposites are increased from 6.2 MPa·m1/2 to 11 MPa·m1/2.
