Ternary Ag/AgC l/BiO IO3 composite photocatalysts are prepared by a facile method. Enhanced visible-light absorption and charge carrier separation are achieved after the introduction of Ag/AgC l particles into BiO IO3...Ternary Ag/AgC l/BiO IO3 composite photocatalysts are prepared by a facile method. Enhanced visible-light absorption and charge carrier separation are achieved after the introduction of Ag/AgC l particles into BiO IO3 systems,as revealed by ultraviolet-visible diffuse-reflectance spectrometry,photocurrent response and electrochemical impedance spectroscopy. The Ag/AgC l/BiO IO3 composites are applied to the visible-light photocatalytic oxidization of NO in air and exhibit an enhanced activity for NO removal in comparison with Ag/AgC l and pure BiO IO3. A possible photocatalytic mechanism for Ag/AgC l/BiO IO3 is proposed,which is related to the surface plasmon resonance effects of Ag metal and the effective carrier separation ability of BiO IO3. This work provides insight into the design and preparation of BiO IO3-based materials with enhanced visible-light photocatalysis ability.展开更多
We study the photodissociation dynamics of nitrous oxide using the time-sliced ion veloc- ity imaging technique at three photolysis wavelengths of 134.20, 135.30, and 136.43 nm. The O（^1Sj=0）＋N2（XI∑g＋） product ...We study the photodissociation dynamics of nitrous oxide using the time-sliced ion veloc- ity imaging technique at three photolysis wavelengths of 134.20, 135.30, and 136.43 nm. The O（^1Sj=0）＋N2（XI∑g＋） product channels were investigated by measuring images of the O（iSj=0） products. Vibrational states of N2（XI∑g＋） products were fully resolved in the images. Product total kinetic energy releases （TKER） and the branching ratios of vibrational states of N2 products were determined. It is found that the most populated vibrational states of N2 products are v--2 and v--3. The angular anisotropy parameters （8 values） were also derived. The β values are very close to 2 at low vibrational states of the correlated N2 （X1 ∑g＋） products at all three photolysis wavelengths, and gradually decrease to about 1.4 at v--7. This indicates the dissociation is mainly through a parallel transition state to form products at lower vibrational states, and the highly vibrational exited products are from a more bent configuration. This is consistent with the observed shift of the most intense rotational structure in the TKER as the vibrational quantum number increases.展开更多
AIM:To explore a simple method to create intestinal autotransplantation in rats and growing pigs and to investigate the effect of L-arginine supplementation on serum nitric oxide (NO), nitric oxide synthase (NOS) and ...AIM:To explore a simple method to create intestinal autotransplantation in rats and growing pigs and to investigate the effect of L-arginine supplementation on serum nitric oxide (NO), nitric oxide synthase (NOS) and intestinal mucosal NOS and Na+-K+-ATPase activity during cold ischemia-reperfusion (IR) in growing pigs. METHODS: In adult Wistar rat models of small bowel autotransplantation, a fine tube was inserted into mesenteric artery via the abdominal aorta. The superior mesenteric artery and vein were occluded. Isolated terminal ileum segment was irrigated with Ringer's solution at 4℃ and preserved in the same solution at 0-4℃ for 60 min. Then, the tube was removed and reperfusion was established. In growing pig models, a terminal ileum segment, 50 cm in length, was isolated and its mesenteric artery was irrigated via a needle with lactated Ringer's solution at 4℃. The method and period of cold preservation and reperfusion were described above. Ten white outbred pigs were randomly divided into control group and experimental group. L-arginine (150 mg/kg) was continuously infused for 15 min before reperfusion and for 30 min after reperfusion in the experimental group. One, 24, 48, and 72 h after reperfusion, peripheral vein blood was respectively collected for NO and NOS determination. At the same time point, intestinal mucosae were also obtained for NOS and Na+-K+-ATPase activity measurement. RESULTS: In adult rat models, 16 of 20 rats sustained the procedure, three died of hemorrhage shock and one of deep anesthesia. In growing pig models, the viability of small bowel graft remained for 72 h after cold IR in eight of 10 pigs. In experimental group, serum NO level at 1 and 24 h after reperfusion increased significantly when compared with control group at the same time point (152.2±61.4μmol/L /s60.8±31.6μmol/L, t=2.802, P=0.02<0.05; 82.2±24.0μmol/L vs 54.0±24.3μmol/L, t=2.490, P=0.04<0.05). Serum NO level increased significantly at 1 h post-reperfusion when compared with the same group before cold IR, 24 and 48 h post-reperfusion (152.2±61.4μmol/L vs 75.6±16.2μmol/L,t=2.820, P=0.02<0.05,82.2±24.0μmol/L,t=2.760, P= 0.03<0.05, 74.2±21.9μmol/L, t=2.822, P= 0.02<0.05). Serum NOS activity at each time point had no significant difference between two groups. In experimental group, intestinal mucosal NOS activity at 1 h post-reperfusion reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.46±0.12 U/mg, t = 3.460, P= 0.009<0.01). Mucosal NOS activity at 24, 48, and 72 h post-reperfusion also reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.57±0.14 U/mg, t= 2.380, P=0.04 <0.05, 0.61±0.11 U/mg, t= 2.309, P = 0.04<0.05, 0.63±0.12U/mg, t = 2.307, P= 0.04<0.05). In control group, mucosal NOS activity at 1 and 24 h post-reperfusion was significantly lower than that in pre-cold IR (0.72±0.12 U/mg vs 0.60±0.07 U/mg, t= 2.320, P= 0.04<0.05, 0.58±0.18 U/mg, t=2.310, P= 0.04<0.05). When compared to the normal value, Na+-K+-ATPase activity increased significantly at 48 and 72 h post-reperfusion in experimental group (2.48±0.59μmol/mg vs 3.89±1.43μmol/mg, t=3.202, P= 0.04<0.05, 3.96±0.86μmol/mg, t=3.401, P= 0.009 <0.01) and control group (2.48±0.59μmol/mg vs 3.58±0.76 μmol/mg, t=2.489, P= 0.04<0.05, 3.67±0.81μmol/mg, t= 2.542, P= 0.03<0.05). CONCLUSION: This novel technique for intestinal autotransplantation provides a potentially consistent and practical model for experimental studies of graft cold preservation. L-arginine supplementation during cold IR may act as a useful adjunct to preserve the grafted intestine.展开更多
Object. The effects of ATP-introduced a rise in cytosolic free Ca2+ concentration and inhibition of nitric oxide were investigated. Method. Measurement of free Ca2+([Ca2+] i)of cultured rat tail arterial smooth muscle...Object. The effects of ATP-introduced a rise in cytosolic free Ca2+ concentration and inhibition of nitric oxide were investigated. Method. Measurement of free Ca2+([Ca2+] i)of cultured rat tail arterial smooth muscle cells using Fura-2/AM dual excitation wavelength spectrofluorometer. Results. There are two components of [Ca2+] i can be evoked by ATP. One part is Ca2+ entry from Ca2+ channel and formed a plateau. The another part is a peak that released from Ca2+ store. Both of them can be inhibited by NO. Conclusion. The ATP induced [Ca2+] i rise that release Ca2+ from both Insp 3 and ryanochine receptors and Ca2+ entry through calcium channels. The inhibition of NO on ATP induced [Ca2+] i rise that was mediated by cGMP.展开更多
基金supported by the National Natural Science Foundation of China(5147807051108487)the Science and Technology Project from Chongqing Education Commission(KJ1400617)~~
文摘Ternary Ag/AgC l/BiO IO3 composite photocatalysts are prepared by a facile method. Enhanced visible-light absorption and charge carrier separation are achieved after the introduction of Ag/AgC l particles into BiO IO3 systems,as revealed by ultraviolet-visible diffuse-reflectance spectrometry,photocurrent response and electrochemical impedance spectroscopy. The Ag/AgC l/BiO IO3 composites are applied to the visible-light photocatalytic oxidization of NO in air and exhibit an enhanced activity for NO removal in comparison with Ag/AgC l and pure BiO IO3. A possible photocatalytic mechanism for Ag/AgC l/BiO IO3 is proposed,which is related to the surface plasmon resonance effects of Ag metal and the effective carrier separation ability of BiO IO3. This work provides insight into the design and preparation of BiO IO3-based materials with enhanced visible-light photocatalysis ability.
基金This work was supported by the National Natural Science Foundation of China （No.21403207 and No.21473173）, the China Postdoctoral Science Foundation （No.2014M551810 and No.2015TS0659）, and the University of Science and Technology of China. We thank Jia-yue Yang, Tian-gang Yang and Wei-qing Zhang for stimulated discussions.
文摘We study the photodissociation dynamics of nitrous oxide using the time-sliced ion veloc- ity imaging technique at three photolysis wavelengths of 134.20, 135.30, and 136.43 nm. The O（^1Sj=0）＋N2（XI∑g＋） product channels were investigated by measuring images of the O（iSj=0） products. Vibrational states of N2（XI∑g＋） products were fully resolved in the images. Product total kinetic energy releases （TKER） and the branching ratios of vibrational states of N2 products were determined. It is found that the most populated vibrational states of N2 products are v--2 and v--3. The angular anisotropy parameters （8 values） were also derived. The β values are very close to 2 at low vibrational states of the correlated N2 （X1 ∑g＋） products at all three photolysis wavelengths, and gradually decrease to about 1.4 at v--7. This indicates the dissociation is mainly through a parallel transition state to form products at lower vibrational states, and the highly vibrational exited products are from a more bent configuration. This is consistent with the observed shift of the most intense rotational structure in the TKER as the vibrational quantum number increases.
基金Supported by the Natural Scientific Foundation of Shandong Province,No.Q99C13
文摘AIM:To explore a simple method to create intestinal autotransplantation in rats and growing pigs and to investigate the effect of L-arginine supplementation on serum nitric oxide (NO), nitric oxide synthase (NOS) and intestinal mucosal NOS and Na+-K+-ATPase activity during cold ischemia-reperfusion (IR) in growing pigs. METHODS: In adult Wistar rat models of small bowel autotransplantation, a fine tube was inserted into mesenteric artery via the abdominal aorta. The superior mesenteric artery and vein were occluded. Isolated terminal ileum segment was irrigated with Ringer's solution at 4℃ and preserved in the same solution at 0-4℃ for 60 min. Then, the tube was removed and reperfusion was established. In growing pig models, a terminal ileum segment, 50 cm in length, was isolated and its mesenteric artery was irrigated via a needle with lactated Ringer's solution at 4℃. The method and period of cold preservation and reperfusion were described above. Ten white outbred pigs were randomly divided into control group and experimental group. L-arginine (150 mg/kg) was continuously infused for 15 min before reperfusion and for 30 min after reperfusion in the experimental group. One, 24, 48, and 72 h after reperfusion, peripheral vein blood was respectively collected for NO and NOS determination. At the same time point, intestinal mucosae were also obtained for NOS and Na+-K+-ATPase activity measurement. RESULTS: In adult rat models, 16 of 20 rats sustained the procedure, three died of hemorrhage shock and one of deep anesthesia. In growing pig models, the viability of small bowel graft remained for 72 h after cold IR in eight of 10 pigs. In experimental group, serum NO level at 1 and 24 h after reperfusion increased significantly when compared with control group at the same time point (152.2±61.4μmol/L /s60.8±31.6μmol/L, t=2.802, P=0.02<0.05; 82.2±24.0μmol/L vs 54.0±24.3μmol/L, t=2.490, P=0.04<0.05). Serum NO level increased significantly at 1 h post-reperfusion when compared with the same group before cold IR, 24 and 48 h post-reperfusion (152.2±61.4μmol/L vs 75.6±16.2μmol/L,t=2.820, P=0.02<0.05,82.2±24.0μmol/L,t=2.760, P= 0.03<0.05, 74.2±21.9μmol/L, t=2.822, P= 0.02<0.05). Serum NOS activity at each time point had no significant difference between two groups. In experimental group, intestinal mucosal NOS activity at 1 h post-reperfusion reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.46±0.12 U/mg, t = 3.460, P= 0.009<0.01). Mucosal NOS activity at 24, 48, and 72 h post-reperfusion also reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.57±0.14 U/mg, t= 2.380, P=0.04 <0.05, 0.61±0.11 U/mg, t= 2.309, P = 0.04<0.05, 0.63±0.12U/mg, t = 2.307, P= 0.04<0.05). In control group, mucosal NOS activity at 1 and 24 h post-reperfusion was significantly lower than that in pre-cold IR (0.72±0.12 U/mg vs 0.60±0.07 U/mg, t= 2.320, P= 0.04<0.05, 0.58±0.18 U/mg, t=2.310, P= 0.04<0.05). When compared to the normal value, Na+-K+-ATPase activity increased significantly at 48 and 72 h post-reperfusion in experimental group (2.48±0.59μmol/mg vs 3.89±1.43μmol/mg, t=3.202, P= 0.04<0.05, 3.96±0.86μmol/mg, t=3.401, P= 0.009 <0.01) and control group (2.48±0.59μmol/mg vs 3.58±0.76 μmol/mg, t=2.489, P= 0.04<0.05, 3.67±0.81μmol/mg, t= 2.542, P= 0.03<0.05). CONCLUSION: This novel technique for intestinal autotransplantation provides a potentially consistent and practical model for experimental studies of graft cold preservation. L-arginine supplementation during cold IR may act as a useful adjunct to preserve the grafted intestine.
文摘Object. The effects of ATP-introduced a rise in cytosolic free Ca2+ concentration and inhibition of nitric oxide were investigated. Method. Measurement of free Ca2+([Ca2+] i)of cultured rat tail arterial smooth muscle cells using Fura-2/AM dual excitation wavelength spectrofluorometer. Results. There are two components of [Ca2+] i can be evoked by ATP. One part is Ca2+ entry from Ca2+ channel and formed a plateau. The another part is a peak that released from Ca2+ store. Both of them can be inhibited by NO. Conclusion. The ATP induced [Ca2+] i rise that release Ca2+ from both Insp 3 and ryanochine receptors and Ca2+ entry through calcium channels. The inhibition of NO on ATP induced [Ca2+] i rise that was mediated by cGMP.
