A novel chemiluminescence .Cl sensor combined with flow-injectionanalysis nas been developed for determining free chlorine in tap water. Takeanalytical reagent luminol was immobilied on an anion exchange res in column...A novel chemiluminescence .Cl sensor combined with flow-injectionanalysis nas been developed for determining free chlorine in tap water. Takeanalytical reagent luminol was immobilied on an anion exchange res in column.Will ie a volume of the sodium hydroxide passed the column, luminol was elutedfrom the res in in a Ika I me aqueous solut ion and then mixed wi th the samples tream to react and produce CI. The CI emiss ion miens ity was correlated ̄  ̄8  ̄' u.i th the standard C10 concentration in the lange of I x 10 to 4 x 10 g ml, andthe detect ion I imi t was & x 10-' g .l-' C10--. Interfering metal ions plesent inwa ter wele effect ively separated by a pre-colunm ca t ion exchanger. A completeana lys is, including sampl lug and washing, could be performed in 1 min wi tha relative standald deviation of less than 5%. The sensor was stable for over 200t imes and has been appl led successfully to the determination of C10 in tapwa t e i.展开更多
A flow injection chemiluminescence (CL) method for the determination of catecholamines is described which is based on their inhibition of the intensity of CL from the luminol-hypochlorite system The hypochlorite was e...A flow injection chemiluminescence (CL) method for the determination of catecholamines is described which is based on their inhibition of the intensity of CL from the luminol-hypochlorite system The hypochlorite was electrogenerated on-line by a constant current electrolysis, resulting in the elimination of the instability of the hypochlorite solution prepared from a commercial reagent of sodium hypochlorite. The detection limits are 0.6 ng/ml for dopamine, 0.8 ng/ml for adrenaline and isoprenaline. The proposed method has been successfully applied to the determination of catecholamines in pharmaceutical injections.展开更多
Palaeo-hydrological field investigation was carried out in the middle reaches of the Jinghe River. A set of palaeoflood slackwater deposit beds was identified in the Holocene loess-soil sequence in the riverbanks. The...Palaeo-hydrological field investigation was carried out in the middle reaches of the Jinghe River. A set of palaeoflood slackwater deposit beds was identified in the Holocene loess-soil sequence in the riverbanks. The sediment samples were collected from the profile, and the particle-size distribution, magnetic susceptibility, loss-on-ignition were analyzed in laboratory. The analytical results showed that the palaeoflood slackwater deposits have recorded extraordinary flood events in the Jinghe River valley. According to stratigraphic correlation and OSL dating, the palaeoflood events were dated to 4100-4000 a BP. The palaeoflood peak discharges were estimated to be 19,410-22,280 m^3/s by using the hydrological model and checked by different approaches. These results have the flood data sequence of the Jinghe River extended to 10,000-year time-scale. It provided significant data for hydraulic engineering and for mitigation of flood hazards in the Jinghe River drainage basin.展开更多
Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solven...Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219 m^2 g^(-1) than the tetraphenylethylene-containing polymer of PrTPE(770 m^2 g^(-1)), which leads to a high CO_2 uptake ability of 3.89 mmol g^(-1) at 1.13 bar/273 K and a H_2 uptake ability of 1.69 wt% at 1.13 bar/77 K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible(UV-Vis) absorption, the lower photoluminescence lifetime, and the higher specific surface area.展开更多
In this paper, a mean-field equation of motion which is derived by Penrose (1991) for the dynamic Ising model with Glauber dynamics is considered. Various finite difference schemes such as explicit Euler scheme, predi...In this paper, a mean-field equation of motion which is derived by Penrose (1991) for the dynamic Ising model with Glauber dynamics is considered. Various finite difference schemes such as explicit Euler scheme, predictor-corrector scheme and some implicit schemes are given and their convergence, stabilities and dynamical properties are discussed. Moreover, a Lyapunov functional for the discrete semigroup {S}(n>0) is constructed. Finally, numerical examples are computed and analyzed. it shows that the model is a better approximation to Cahn-Allen equation which is mentioned in Penrose (1991).展开更多
Based on Jacobson’s molecular free length theory in liquids and the relationship between the ultrasonic velocity and the molecular free length in organic liquids, the equations of pressure coefficient and temperature...Based on Jacobson’s molecular free length theory in liquids and the relationship between the ultrasonic velocity and the molecular free length in organic liquids, the equations of pressure coefficient and temperature coefficient of ultrasonic velocity in organic liquids are derived . The calculated pressure coefficient and temperature coefficient of ultrasonic velocity are in good agreement with the measured results.展开更多
Of ICE protease family, CPP32 (apopain or Yama) plays a central role in different apoptotic pathways. To study the molecules regulating CPP32, yeast two_hybrid system was used to identify proteins (peptides) that inte...Of ICE protease family, CPP32 (apopain or Yama) plays a central role in different apoptotic pathways. To study the molecules regulating CPP32, yeast two_hybrid system was used to identify proteins (peptides) that interact with CPP32. First, the CPP32 gene was cloned into plasmid vector pGBT9. The resulting recombinant plasmid was designated as pGBT9/CPP. The pGBT9 /CPP plasmid was transformed into the yeast strain HF7C, then the leukemia library was introduced. The transformation mixture was plated on medium lacking Trp, Leu and His in the initial screen. Colonies growing on the selection medium were further assayed for β galactosidase activity. Within 42 Trp +Leu +His + colonies only 5 turned blue in the presence of X_Gal. Plasmid DNA from 5 positive yeast colonies was prepared respectively and used to transform HB101 by electroporation. The transformation mixture was plated on medium lacking Leu to be selected for the library plasmid. Finally, only one library plasmid, designated as pY1, was determined to be truly positive by retransformation of pGBT9/CPP and the library plasmid into HF7C. The inserted cDNA of pY1 encodes a peptide of 15 amino acids, suggesting that it may be the domain interacting with CPP32.展开更多
文摘A novel chemiluminescence .Cl sensor combined with flow-injectionanalysis nas been developed for determining free chlorine in tap water. Takeanalytical reagent luminol was immobilied on an anion exchange res in column.Will ie a volume of the sodium hydroxide passed the column, luminol was elutedfrom the res in in a Ika I me aqueous solut ion and then mixed wi th the samples tream to react and produce CI. The CI emiss ion miens ity was correlated ̄  ̄8  ̄' u.i th the standard C10 concentration in the lange of I x 10 to 4 x 10 g ml, andthe detect ion I imi t was & x 10-' g .l-' C10--. Interfering metal ions plesent inwa ter wele effect ively separated by a pre-colunm ca t ion exchanger. A completeana lys is, including sampl lug and washing, could be performed in 1 min wi tha relative standald deviation of less than 5%. The sensor was stable for over 200t imes and has been appl led successfully to the determination of C10 in tapwa t e i.
文摘A flow injection chemiluminescence (CL) method for the determination of catecholamines is described which is based on their inhibition of the intensity of CL from the luminol-hypochlorite system The hypochlorite was electrogenerated on-line by a constant current electrolysis, resulting in the elimination of the instability of the hypochlorite solution prepared from a commercial reagent of sodium hypochlorite. The detection limits are 0.6 ng/ml for dopamine, 0.8 ng/ml for adrenaline and isoprenaline. The proposed method has been successfully applied to the determination of catecholamines in pharmaceutical injections.
基金National Natural Science Foundation of China, No.41030637 Fundamental Research Funds for Central Universities, No.GK200901007
文摘Palaeo-hydrological field investigation was carried out in the middle reaches of the Jinghe River. A set of palaeoflood slackwater deposit beds was identified in the Holocene loess-soil sequence in the riverbanks. The sediment samples were collected from the profile, and the particle-size distribution, magnetic susceptibility, loss-on-ignition were analyzed in laboratory. The analytical results showed that the palaeoflood slackwater deposits have recorded extraordinary flood events in the Jinghe River valley. According to stratigraphic correlation and OSL dating, the palaeoflood events were dated to 4100-4000 a BP. The palaeoflood peak discharges were estimated to be 19,410-22,280 m^3/s by using the hydrological model and checked by different approaches. These results have the flood data sequence of the Jinghe River extended to 10,000-year time-scale. It provided significant data for hydraulic engineering and for mitigation of flood hazards in the Jinghe River drainage basin.
基金supported by the National Natural Science Foundation of China(21574077,21304055)the Fundamental Research Funds for the Central Universities(GK201501002,2016CBZ001)the Opening Project of State Key Laboratory of Polymer Materials Engineering from Sichuan University(sklpme2016-4-22)
文摘Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219 m^2 g^(-1) than the tetraphenylethylene-containing polymer of PrTPE(770 m^2 g^(-1)), which leads to a high CO_2 uptake ability of 3.89 mmol g^(-1) at 1.13 bar/273 K and a H_2 uptake ability of 1.69 wt% at 1.13 bar/77 K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible(UV-Vis) absorption, the lower photoluminescence lifetime, and the higher specific surface area.
文摘In this paper, a mean-field equation of motion which is derived by Penrose (1991) for the dynamic Ising model with Glauber dynamics is considered. Various finite difference schemes such as explicit Euler scheme, predictor-corrector scheme and some implicit schemes are given and their convergence, stabilities and dynamical properties are discussed. Moreover, a Lyapunov functional for the discrete semigroup {S}(n>0) is constructed. Finally, numerical examples are computed and analyzed. it shows that the model is a better approximation to Cahn-Allen equation which is mentioned in Penrose (1991).
文摘Based on Jacobson’s molecular free length theory in liquids and the relationship between the ultrasonic velocity and the molecular free length in organic liquids, the equations of pressure coefficient and temperature coefficient of ultrasonic velocity in organic liquids are derived . The calculated pressure coefficient and temperature coefficient of ultrasonic velocity are in good agreement with the measured results.
文摘Of ICE protease family, CPP32 (apopain or Yama) plays a central role in different apoptotic pathways. To study the molecules regulating CPP32, yeast two_hybrid system was used to identify proteins (peptides) that interact with CPP32. First, the CPP32 gene was cloned into plasmid vector pGBT9. The resulting recombinant plasmid was designated as pGBT9/CPP. The pGBT9 /CPP plasmid was transformed into the yeast strain HF7C, then the leukemia library was introduced. The transformation mixture was plated on medium lacking Trp, Leu and His in the initial screen. Colonies growing on the selection medium were further assayed for β galactosidase activity. Within 42 Trp +Leu +His + colonies only 5 turned blue in the presence of X_Gal. Plasmid DNA from 5 positive yeast colonies was prepared respectively and used to transform HB101 by electroporation. The transformation mixture was plated on medium lacking Leu to be selected for the library plasmid. Finally, only one library plasmid, designated as pY1, was determined to be truly positive by retransformation of pGBT9/CPP and the library plasmid into HF7C. The inserted cDNA of pY1 encodes a peptide of 15 amino acids, suggesting that it may be the domain interacting with CPP32.