The structures and dielectric properties of Ba6-3xNd8＋2xTi18O54 system（x=2/3） doped with different contents of Bi2O3, whose final molecular formula is Ba6-3x（Nd1-yBiy）8＋2xTi18O54 were investigated. It is indicat...The structures and dielectric properties of Ba6-3xNd8＋2xTi18O54 system（x=2/3） doped with different contents of Bi2O3, whose final molecular formula is Ba6-3x（Nd1-yBiy）8＋2xTi18O54 were investigated. It is indicated that the dielectric constant increases greatly whereas Q value（f0=4 GHz） decreases with the increase of Bi2O3 content. However, the temperature coefficient could be controlled below 0±30×10^-6/℃ in the experiment. These phenomena are related to the appearance of a new phase, Bi4Ti3O12, which has high dielectric constant. Also, that Bi^3＋（0.13 nm） substitutes for Nd^3＋（0.099 5 nm） will increase the unit cell volume, which will lead to the enlargement of the octahedron B site occupied by Ti^4＋. So the spontaneous polarization of Ti^4＋ ions will be strengthened. Besides, Bi^3＋ will fill up some vacancies which Ba^2＋ or Nd^3＋ ions leave in two A1 sites and four A2 sites. More positive ions polarize, which also contributes to higher dielectric constant. The samples got with the optimium properties are sintered at 1 200 ℃ for 4 h, when y=0.25, ε≈110, Q≈5 400（f0=4 GHz）, TCC=-4.7×10^-6/℃; When y=0.3, ε≈120, Q≈5 000（f0=4 GHz）, TCC=-24×10^-6/℃.展开更多
To better understand the formation of H2O2 in the ozonation of nitrobenzene and its role for the oxidation,a batch reactor of nitrobenzene ozonation was set up.The variables such as pH value,ozone dosage,and the prese...To better understand the formation of H2O2 in the ozonation of nitrobenzene and its role for the oxidation,a batch reactor of nitrobenzene ozonation was set up.The variables such as pH value,ozone dosage,and the presence of hydroxyl radical scavenger were investigated.The results showed that high accumulations of H2O2 were generally formed at low pH values and low ozone dosages.Moreover,H2O2 mainly formed after nitrobenzene was oxidized by hydroxyl radical during ozonation of the intermediates,such as p-nitrophenol,which reacted with ozone quickly in water.A small amount of additional H2O2 enhanced the nitrobenzene removal slightly.The kinetic study showed that nitrobenzene degradation fitted with pseudo-second-order kinetics well in the experiment.The kinetic constant values correlated linearly with the concentrations of H2O2 added.Thus,it is expected that the H2O2 formed in oxidation of nitrobenzene may initiate ozone decomposition to form hydroxyl radical and finally enhance the degradation of aromatic compounds to a certain extent.展开更多
We report the study on the complete three-body Coulomb explosion(CE)of N_(2)O^(q+)(q=5,6)induced by 56-keV/u Ne8+ion collision with N2O gaseous molecule.Six CE channels for N_(2)O^(5+)and seven for N_(2)O^(6+)are iden...We report the study on the complete three-body Coulomb explosion(CE)of N_(2)O^(q+)(q=5,6)induced by 56-keV/u Ne8+ion collision with N2O gaseous molecule.Six CE channels for N_(2)O^(5+)and seven for N_(2)O^(6+)are identified by measuring three ionic fragments and the charge-changed projectile in quadruple coincidence.Correspondingly the kinetic energy release(KER)and momentum correlation angle(MCA)distributions of three ionic fragments for each of the CE channels are also deduced.Numerical computation is presented to reconstruct the geometric structure of N_(2)O^(q+0prior to dissociation based on the measured KER and MCA.The N–N and N–O bond lengths and the N–N–O bond angles of N_(2)O^(q+)for each of the channels are determined.展开更多
Two full-scale systems operated in parallel, a conventional A2/O system consisting of anaerobic, anoxic and oxic compartments in succession and an inverted system consisting of anoxic, anaerobic and oxic compartments ...Two full-scale systems operated in parallel, a conventional A2/O system consisting of anaerobic, anoxic and oxic compartments in succession and an inverted system consisting of anoxic, anaerobic and oxic compartments without internal recycle, were compared in terms of their phosphorus removal performance, with an emphasis on phosphate （P） release behaviors, using both operational data and simulation results. The inverted system exhibited better long-term phosphorus removal performance （0.2 ± 0.3 vs. 0.7 ±0.7 mg/L）, which should be attributed to the higher P release rate （0.79 vs. 0.60 kg P/（kg MLSS.day）） in the non-aerated compartments. The P release occurred in both the anoxic and anaerobic compartments of the inverted system, resulting in more efficient P release. Although the abundances of the ＇Candidatus Accumulibacter phosphatis＇ population in the two systems were quite similar （（19.1 ＋ 3.27）% and （18.4 ＋ 4.15）% of the total microbe （DAPI stained particles） population in the inverted and conventional systems, respectively, by fluorescence in situ hybridization （FISH））, the high-concentration DAPI staining results show that the abundances of the whole polyphosphate accumulating organisms （PAOs） in the aerobic ends were quite different （the average ratios of the poly-P granules to total microbes （DAPI stained particles） were （45 ±4.18）% and （35 ± 5.39）%, respectively）. Both the operational data and simulation results showed that the inverted system retained more abundant PAO populations due to its special configuration, which permitted efficient P release in the non-aerated compartment and better P removal,展开更多
Novel multifunctional nanoparticles containing a magnetic Fe3O4@SiO2 sphere and a biocompatible block copolymer poly(ethylene glycol)-b-poly(aspartate)(PEG-b-PAsp) were prepared.The silica coated on the superparamagne...Novel multifunctional nanoparticles containing a magnetic Fe3O4@SiO2 sphere and a biocompatible block copolymer poly(ethylene glycol)-b-poly(aspartate)(PEG-b-PAsp) were prepared.The silica coated on the superparamagnetic core was able to achieve a magnetic dispersivity,as well as to protect Fe3O4 against oxidation and acid corrosion.The PAsp block was grafted to the surface of Fe3O4@SiO2 nanoparticles by amido bonds,and the PEG block formed the outermost shell.The anticancer agent doxorubicin(DOX) was loaded into the hybrid nanoparticles via an electrostatic interaction between DOX and PAsp.The release rate of DOX could be adjusted by the pH value.展开更多
Considering that high levels of nitric oxide(NO) exert anti-cancer effect and the derivatives of oleanolic acid(OA) have shown potent anti-cancer activity, new O^2-vinyl diazeniumdiolate-based NO releasing derivatives...Considering that high levels of nitric oxide(NO) exert anti-cancer effect and the derivatives of oleanolic acid(OA) have shown potent anti-cancer activity, new O^2-vinyl diazeniumdiolate-based NO releasing derivatives(5a–l, 11a–l) of OA were designed, synthesized, and biologically evaluated in the present study. These derivatives could release different amounts of NO in liver cells. Among them, 5d, 5i, 5j, 11g, 11h, and 11j released more NO in SMMC-7721 cells and displayed stronger proliferative inhibition against SMMC-7721 and Hep G2 cells than OA and other tested compounds. The most active compound 5j showed almost 20-fold better solubility than OA in aqueous solution, released larger amounts of NO in liver cancer cells than that in normal ones, and exhibited potent anti-hepatocellular carcinoma activity but little effect on the normal liver cells. The inhibitory activity against the cancer cells was significantly diminished upon addition of an NO scavenger, suggesting that NO may contribute, at least in part, to the activity of 5j.展开更多
In order to improve the therapeutic index and reduce the side effects of As2O3 so as to expand its clinical utility to solid tumors,As2O3-loaded polylactic acid（PLA）/magnetic nanoparticles（PAMNs） were prepared and...In order to improve the therapeutic index and reduce the side effects of As2O3 so as to expand its clinical utility to solid tumors,As2O3-loaded polylactic acid（PLA）/magnetic nanoparticles（PAMNs） were prepared and the preparation conditions were optimized by the improved double emulsion solvent-evaporation method to obtain as a drug delivery system with a high As2O3 encapsulation efficiency and homogeneous nanosized particles.Successful loading of magnetic nanoparticles into the nanoparticles was confirmed by Fourier transform infrared（FTIR） spectroscopy.The drug loading,encapsulation efficiency and releasing properties of As2O3 in PAMNs were investigated by atomic fluorescence spectrometer analysis.Subsequently,the in vitro antitumor efficacy of free As2O3 and As2O3-PAMNs against SMMC-7721 cell line was investigated.Finally,confocal fluorescence microscopy was conducted to reveal the celluar uptake of As2O3-loaded PAMNs by SMMC-7721 cell line.展开更多
基金the Natural Science Foundation of Tianjin(No.06YFJMJC01000)
文摘The structures and dielectric properties of Ba6-3xNd8＋2xTi18O54 system（x=2/3） doped with different contents of Bi2O3, whose final molecular formula is Ba6-3x（Nd1-yBiy）8＋2xTi18O54 were investigated. It is indicated that the dielectric constant increases greatly whereas Q value（f0=4 GHz） decreases with the increase of Bi2O3 content. However, the temperature coefficient could be controlled below 0±30×10^-6/℃ in the experiment. These phenomena are related to the appearance of a new phase, Bi4Ti3O12, which has high dielectric constant. Also, that Bi^3＋（0.13 nm） substitutes for Nd^3＋（0.099 5 nm） will increase the unit cell volume, which will lead to the enlargement of the octahedron B site occupied by Ti^4＋. So the spontaneous polarization of Ti^4＋ ions will be strengthened. Besides, Bi^3＋ will fill up some vacancies which Ba^2＋ or Nd^3＋ ions leave in two A1 sites and four A2 sites. More positive ions polarize, which also contributes to higher dielectric constant. The samples got with the optimium properties are sintered at 1 200 ℃ for 4 h, when y=0.25, ε≈110, Q≈5 400（f0=4 GHz）, TCC=-4.7×10^-6/℃; When y=0.3, ε≈120, Q≈5 000（f0=4 GHz）, TCC=-24×10^-6/℃.
基金Supported by the National Natural Science Foundation of China(21407077)the Postdoctoral Science Foundation of Jiangsu Province(1002013C)+1 种基金the Fundamental Research Funds for the Central Universities(308201NS2012079)the Priority Academic Program Development Fund of Jiangsu Higher Education Institutions
文摘To better understand the formation of H2O2 in the ozonation of nitrobenzene and its role for the oxidation,a batch reactor of nitrobenzene ozonation was set up.The variables such as pH value,ozone dosage,and the presence of hydroxyl radical scavenger were investigated.The results showed that high accumulations of H2O2 were generally formed at low pH values and low ozone dosages.Moreover,H2O2 mainly formed after nitrobenzene was oxidized by hydroxyl radical during ozonation of the intermediates,such as p-nitrophenol,which reacted with ozone quickly in water.A small amount of additional H2O2 enhanced the nitrobenzene removal slightly.The kinetic study showed that nitrobenzene degradation fitted with pseudo-second-order kinetics well in the experiment.The kinetic constant values correlated linearly with the concentrations of H2O2 added.Thus,it is expected that the H2O2 formed in oxidation of nitrobenzene may initiate ozone decomposition to form hydroxyl radical and finally enhance the degradation of aromatic compounds to a certain extent.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2017YFA0402300 and 2017YFA0303501)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB34000000)。
文摘We report the study on the complete three-body Coulomb explosion(CE)of N_(2)O^(q+)(q=5,6)induced by 56-keV/u Ne8+ion collision with N2O gaseous molecule.Six CE channels for N_(2)O^(5+)and seven for N_(2)O^(6+)are identified by measuring three ionic fragments and the charge-changed projectile in quadruple coincidence.Correspondingly the kinetic energy release(KER)and momentum correlation angle(MCA)distributions of three ionic fragments for each of the CE channels are also deduced.Numerical computation is presented to reconstruct the geometric structure of N_(2)O^(q+0prior to dissociation based on the measured KER and MCA.The N–N and N–O bond lengths and the N–N–O bond angles of N_(2)O^(q+)for each of the channels are determined.
基金supported by the National Natural Science Foundation of China (No. 20921140094)the Knowledge Innovation Project of Chinese Academy of Sciences(No. KSCX2-YW-G-054)
文摘Two full-scale systems operated in parallel, a conventional A2/O system consisting of anaerobic, anoxic and oxic compartments in succession and an inverted system consisting of anoxic, anaerobic and oxic compartments without internal recycle, were compared in terms of their phosphorus removal performance, with an emphasis on phosphate （P） release behaviors, using both operational data and simulation results. The inverted system exhibited better long-term phosphorus removal performance （0.2 ± 0.3 vs. 0.7 ±0.7 mg/L）, which should be attributed to the higher P release rate （0.79 vs. 0.60 kg P/（kg MLSS.day）） in the non-aerated compartments. The P release occurred in both the anoxic and anaerobic compartments of the inverted system, resulting in more efficient P release. Although the abundances of the ＇Candidatus Accumulibacter phosphatis＇ population in the two systems were quite similar （（19.1 ＋ 3.27）% and （18.4 ＋ 4.15）% of the total microbe （DAPI stained particles） population in the inverted and conventional systems, respectively, by fluorescence in situ hybridization （FISH））, the high-concentration DAPI staining results show that the abundances of the whole polyphosphate accumulating organisms （PAOs） in the aerobic ends were quite different （the average ratios of the poly-P granules to total microbes （DAPI stained particles） were （45 ±4.18）% and （35 ± 5.39）%, respectively）. Both the operational data and simulation results showed that the inverted system retained more abundant PAO populations due to its special configuration, which permitted efficient P release in the non-aerated compartment and better P removal,
基金supported by the National Natural Science Foundation of China (Grant Nos 20774051,50625310,and 50830103)the Opening Foundation of Sichuan University
文摘Novel multifunctional nanoparticles containing a magnetic Fe3O4@SiO2 sphere and a biocompatible block copolymer poly(ethylene glycol)-b-poly(aspartate)(PEG-b-PAsp) were prepared.The silica coated on the superparamagnetic core was able to achieve a magnetic dispersivity,as well as to protect Fe3O4 against oxidation and acid corrosion.The PAsp block was grafted to the surface of Fe3O4@SiO2 nanoparticles by amido bonds,and the PEG block formed the outermost shell.The anticancer agent doxorubicin(DOX) was loaded into the hybrid nanoparticles via an electrostatic interaction between DOX and PAsp.The release rate of DOX could be adjusted by the pH value.
基金supported by grants from the National Natural Science Foundation of China(Nos.81273378 and 21372261)
文摘Considering that high levels of nitric oxide(NO) exert anti-cancer effect and the derivatives of oleanolic acid(OA) have shown potent anti-cancer activity, new O^2-vinyl diazeniumdiolate-based NO releasing derivatives(5a–l, 11a–l) of OA were designed, synthesized, and biologically evaluated in the present study. These derivatives could release different amounts of NO in liver cells. Among them, 5d, 5i, 5j, 11g, 11h, and 11j released more NO in SMMC-7721 cells and displayed stronger proliferative inhibition against SMMC-7721 and Hep G2 cells than OA and other tested compounds. The most active compound 5j showed almost 20-fold better solubility than OA in aqueous solution, released larger amounts of NO in liver cancer cells than that in normal ones, and exhibited potent anti-hepatocellular carcinoma activity but little effect on the normal liver cells. The inhibitory activity against the cancer cells was significantly diminished upon addition of an NO scavenger, suggesting that NO may contribute, at least in part, to the activity of 5j.
基金Supported by the National Natural Science Foundation of China（Nos.21201149,51273171）,the Natural Science Foundation of Jiangsu Province,China（No.BK2012259）,the Jiangsu College Graduate Research and Innovation Programs,China （No.CXLX12_0914）,the Project of the Testing Center of Yangzhou University（China） and the Priority Academic Program Development of Jiangsu Higher Education Institutions（China）.
文摘In order to improve the therapeutic index and reduce the side effects of As2O3 so as to expand its clinical utility to solid tumors,As2O3-loaded polylactic acid（PLA）/magnetic nanoparticles（PAMNs） were prepared and the preparation conditions were optimized by the improved double emulsion solvent-evaporation method to obtain as a drug delivery system with a high As2O3 encapsulation efficiency and homogeneous nanosized particles.Successful loading of magnetic nanoparticles into the nanoparticles was confirmed by Fourier transform infrared（FTIR） spectroscopy.The drug loading,encapsulation efficiency and releasing properties of As2O3 in PAMNs were investigated by atomic fluorescence spectrometer analysis.Subsequently,the in vitro antitumor efficacy of free As2O3 and As2O3-PAMNs against SMMC-7721 cell line was investigated.Finally,confocal fluorescence microscopy was conducted to reveal the celluar uptake of As2O3-loaded PAMNs by SMMC-7721 cell line.
