The effect of sulfur dioxide （SO2） on the formation of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs） has been studied in an entrained-flow reactor （EFR） under simulated wa...The effect of sulfur dioxide （SO2） on the formation of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs） has been studied in an entrained-flow reactor （EFR） under simulated waste combustion conditions. A chlorination model based on conditional probability was employed to evaluate the homologue patterns of PCDDs and PCDFs. Results revealed that the presence of SO2 did not alter the formation pathway although SO2 suppressed PCDD/F formation. The prediction model of PCDF showed good agreement with the experimental data （R--0.95）, whereas the prediction for PCDDs did not correlate well with the experimental data. This may be explained because potential chlorination pathways play a significant role in PCDF formation, whereas PCDDs are mainly formed through condensation reactions. Furthermore, the result indicated that the steric hindrance during formation has more effects on PCDD than on PCDF due to the symmetric molecular structures of PCDDs.展开更多
Coordinated signal processing can obtain a huge transmission gain for Fog Radio Access Networks(F-RANs).However,integrating into large scale,it will lead to high computation complexity in channel estimation and spectr...Coordinated signal processing can obtain a huge transmission gain for Fog Radio Access Networks(F-RANs).However,integrating into large scale,it will lead to high computation complexity in channel estimation and spectral efficiency loss in transmission performance.Thus,a joint cluster formation and channel estimation scheme is proposed in this paper.Considering research remote radio heads(RRHs)centred serving scheme,a coalition game is formulated in order to maximize the spectral efficiency of cooperative RRHs under the conditions of balancing the data rate and the cost of channel estimation.As the cost influences to the necessary consumption of training length and estimation error.Particularly,an iterative semi-blind channel estimation and symbol detection approach is designed by expectation maximization algorithm,where the channel estimation process is initialized by subspace method with lower pilot length.Finally,the simulation results show that a stable cluster formation is established by our proposed coalition game method and it outperforms compared with full coordinated schemes.展开更多
The anodic voltammetric curves of heavily doped n-Si in HF solution, on which three different regions have emerged, and were plotted, A porous silicon layer with fine morphology was formed in linear region.
In this paper, the thermodynamic parameters are calculated for all gaseous Poly Chlorinat Dibenzo-p-dioxins （PCDDs） using the Density Functional Theory （DFF） method and both the enthalpy of formation （ΔfH^0） an...In this paper, the thermodynamic parameters are calculated for all gaseous Poly Chlorinat Dibenzo-p-dioxins （PCDDs） using the Density Functional Theory （DFF） method and both the enthalpy of formation （ΔfH^0） and Gibbs free energy of formation （Δf G^0） are derived, from which the order of stability of individual congeners is then predicted. All these properties, together with the calculated entropies （ S^0） and heat capacities （ Cp）, are presented as a function of the number of chlorine atoms in the various PCDD molecules. The accuracy of the method used here, is evaluated by comparing the thermodynamic parameters of gaseous chlorobenzenes with experimental values collected from literature.展开更多
For the first time in P. R. China, six locations were investigated regarding the impact of poloychlorinated dibenzo-p-dioxins (PCDs) and polychlorinated dibenzofurans (PCDFs) in contaminated sediments and soils in the...For the first time in P. R. China, six locations were investigated regarding the impact of poloychlorinated dibenzo-p-dioxins (PCDs) and polychlorinated dibenzofurans (PCDFs) in contaminated sediments and soils in the Ya-Er Lake area . Total concentrations of PCDDs from 70 to 1.6 ×105 ng/kg dw ,median 7.9×104 ng/kg dw and of PCDFs from 1.8 to 1.8 ×104ng/kg dw ,median 9.2 ×103 ng/kg dw were measured . The internaional toxic equivalents (I-TEQ) varied from 0.14 to 8.1×10 2 ng/kg dw,median 4.1×102 ng/kg dw The PCDDs pattern showed that the concentration of OCDD was significantly higher than that of the low chlorinated congeners . The results indicated that parts of Ya-Er Lake are heavily pollutad by there chiorinated compounds. Comparison of our results with the pattern of sediments showed significant differences . The asults are of special importance bocause the pollution that affected Ya-Er Lake may spread to agricultural land and the Changjiang River.展开更多
禾长蠕孢菌(Helminthosporium gramineum f. sp. echinochloae,HGE)是稗草生防潜力菌,为建立HGE的遗传转化体系,研究了菌龄、胞壁降解酶、稳渗剂等对其原生质体制备和再生的影响。结果表明,HGE菌原生质体制备的适宜条件为:26℃下采用1.0...禾长蠕孢菌(Helminthosporium gramineum f. sp. echinochloae,HGE)是稗草生防潜力菌,为建立HGE的遗传转化体系,研究了菌龄、胞壁降解酶、稳渗剂等对其原生质体制备和再生的影响。结果表明,HGE菌原生质体制备的适宜条件为:26℃下采用1.0%崩溃酶处理菌龄为6h的HGE菌丝体2h,0.7mol/LNaCl为稳渗剂。原生质体再生的适宜条件为:32℃下采用0.5%崩溃酶处理菌龄为16h的HGE菌丝体4h,0.7mol/LNaCl为稳渗剂,R1为高渗再生培养基。展开更多
基金Project supported by the China Scholarship Council Foundation (2003) the National Natural Science Foundation of China (No. 50576082).
文摘The effect of sulfur dioxide （SO2） on the formation of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs） has been studied in an entrained-flow reactor （EFR） under simulated waste combustion conditions. A chlorination model based on conditional probability was employed to evaluate the homologue patterns of PCDDs and PCDFs. Results revealed that the presence of SO2 did not alter the formation pathway although SO2 suppressed PCDD/F formation. The prediction model of PCDF showed good agreement with the experimental data （R--0.95）, whereas the prediction for PCDDs did not correlate well with the experimental data. This may be explained because potential chlorination pathways play a significant role in PCDF formation, whereas PCDDs are mainly formed through condensation reactions. Furthermore, the result indicated that the steric hindrance during formation has more effects on PCDD than on PCDF due to the symmetric molecular structures of PCDDs.
基金supported in part by the State Major Science and Technology Special Project(Grant No.2018ZX03001025)the National Natural Science Foundation of China(No.61831002 and No.61671074)the Fundamental Research Funds for the Central Universities under Grant No.2018XKJC01
文摘Coordinated signal processing can obtain a huge transmission gain for Fog Radio Access Networks(F-RANs).However,integrating into large scale,it will lead to high computation complexity in channel estimation and spectral efficiency loss in transmission performance.Thus,a joint cluster formation and channel estimation scheme is proposed in this paper.Considering research remote radio heads(RRHs)centred serving scheme,a coalition game is formulated in order to maximize the spectral efficiency of cooperative RRHs under the conditions of balancing the data rate and the cost of channel estimation.As the cost influences to the necessary consumption of training length and estimation error.Particularly,an iterative semi-blind channel estimation and symbol detection approach is designed by expectation maximization algorithm,where the channel estimation process is initialized by subspace method with lower pilot length.Finally,the simulation results show that a stable cluster formation is established by our proposed coalition game method and it outperforms compared with full coordinated schemes.
文摘The anodic voltammetric curves of heavily doped n-Si in HF solution, on which three different regions have emerged, and were plotted, A porous silicon layer with fine morphology was formed in linear region.
文摘In this paper, the thermodynamic parameters are calculated for all gaseous Poly Chlorinat Dibenzo-p-dioxins （PCDDs） using the Density Functional Theory （DFF） method and both the enthalpy of formation （ΔfH^0） and Gibbs free energy of formation （Δf G^0） are derived, from which the order of stability of individual congeners is then predicted. All these properties, together with the calculated entropies （ S^0） and heat capacities （ Cp）, are presented as a function of the number of chlorine atoms in the various PCDD molecules. The accuracy of the method used here, is evaluated by comparing the thermodynamic parameters of gaseous chlorobenzenes with experimental values collected from literature.
文摘For the first time in P. R. China, six locations were investigated regarding the impact of poloychlorinated dibenzo-p-dioxins (PCDs) and polychlorinated dibenzofurans (PCDFs) in contaminated sediments and soils in the Ya-Er Lake area . Total concentrations of PCDDs from 70 to 1.6 ×105 ng/kg dw ,median 7.9×104 ng/kg dw and of PCDFs from 1.8 to 1.8 ×104ng/kg dw ,median 9.2 ×103 ng/kg dw were measured . The internaional toxic equivalents (I-TEQ) varied from 0.14 to 8.1×10 2 ng/kg dw,median 4.1×102 ng/kg dw The PCDDs pattern showed that the concentration of OCDD was significantly higher than that of the low chlorinated congeners . The results indicated that parts of Ya-Er Lake are heavily pollutad by there chiorinated compounds. Comparison of our results with the pattern of sediments showed significant differences . The asults are of special importance bocause the pollution that affected Ya-Er Lake may spread to agricultural land and the Changjiang River.
文摘禾长蠕孢菌(Helminthosporium gramineum f. sp. echinochloae,HGE)是稗草生防潜力菌,为建立HGE的遗传转化体系,研究了菌龄、胞壁降解酶、稳渗剂等对其原生质体制备和再生的影响。结果表明,HGE菌原生质体制备的适宜条件为:26℃下采用1.0%崩溃酶处理菌龄为6h的HGE菌丝体2h,0.7mol/LNaCl为稳渗剂。原生质体再生的适宜条件为:32℃下采用0.5%崩溃酶处理菌龄为16h的HGE菌丝体4h,0.7mol/LNaCl为稳渗剂,R1为高渗再生培养基。
