A new process for preparing poly(phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichlorobenzamide (DCBA) and alkali in polar orga...A new process for preparing poly(phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure (called sulfur solution route), is reported in the present paper. The influences of polymerization time, molar ratio of precursors, catalyst and solvent upon the polymer were investigated. To seek the best parameters of polymerization, orthogonal design was employed in the experiments. The results indicate that the molar ratio of precursors is the most significant effect on both of viscosity and yield of the polymer. The suitable parameters for preparing the related polymer are presented. The polymer was characterized by IRspectrum, 1HNMRspectrum and Raman spectrum, etc.展开更多
This paper presents a sequential optimum algorithm for vehicle schedulingproblem, which includes obtaining initial theoretical solution, adjustingsolution, forming initial routes and adjustins routes. This method can ...This paper presents a sequential optimum algorithm for vehicle schedulingproblem, which includes obtaining initial theoretical solution, adjustingsolution, forming initial routes and adjustins routes. This method can beapplied to general transportation problems with multiple depots and multiplevehicle types on complex network. In comparison with manual scheduling ofChengdu Transportation Company II, the result shows that this method isreasonable, feasible and applicable.展开更多
Cobalt carbide nanoparticles(NPs),as a typical carbide material,have attracted extensive attention in the fields of magnetism and electrochemistry.Herein,we adopted a modified solution route by pyrolysis long-chain am...Cobalt carbide nanoparticles(NPs),as a typical carbide material,have attracted extensive attention in the fields of magnetism and electrochemistry.Herein,we adopted a modified solution route by pyrolysis long-chain amines at high temperatures to obtain Co_(2)C NPs,in which different forms of Co NPs were used as precursors.The results reveal that no matter what the structure of the precursor and the type of long-chain amine,single-phase Co_(2)C NPs with good crystallinity are obtained.At the same time,carbonization of hexagonal close packed(hcp)cobalt as the precursor gives the materials high magnetic anisotropy,exhibiting a large coercivity(~1,300 Oe)on the nanoscale.In terms of catalytic properties,benefiting from intrinsically high activity of Co_(2)C NPs,the material demonstrates superior hydrogen evolution reaction(HER)performance,with optimal overpotential as low as 73 mV at the current density of 10 mA·cm^(-2).This provides new ideas for the further development of transition metal carbides(TMCs)and the improvement of their magnetic and electrocatalytic properties.展开更多
文摘A new process for preparing poly(phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure (called sulfur solution route), is reported in the present paper. The influences of polymerization time, molar ratio of precursors, catalyst and solvent upon the polymer were investigated. To seek the best parameters of polymerization, orthogonal design was employed in the experiments. The results indicate that the molar ratio of precursors is the most significant effect on both of viscosity and yield of the polymer. The suitable parameters for preparing the related polymer are presented. The polymer was characterized by IRspectrum, 1HNMRspectrum and Raman spectrum, etc.
文摘This paper presents a sequential optimum algorithm for vehicle schedulingproblem, which includes obtaining initial theoretical solution, adjustingsolution, forming initial routes and adjustins routes. This method can beapplied to general transportation problems with multiple depots and multiplevehicle types on complex network. In comparison with manual scheduling ofChengdu Transportation Company II, the result shows that this method isreasonable, feasible and applicable.
基金This work was supported by the National Natural Science Foundation of China(No.51872111)the Natural Science Foundation of Jilin Province(No.20190201253JC).
文摘Cobalt carbide nanoparticles(NPs),as a typical carbide material,have attracted extensive attention in the fields of magnetism and electrochemistry.Herein,we adopted a modified solution route by pyrolysis long-chain amines at high temperatures to obtain Co_(2)C NPs,in which different forms of Co NPs were used as precursors.The results reveal that no matter what the structure of the precursor and the type of long-chain amine,single-phase Co_(2)C NPs with good crystallinity are obtained.At the same time,carbonization of hexagonal close packed(hcp)cobalt as the precursor gives the materials high magnetic anisotropy,exhibiting a large coercivity(~1,300 Oe)on the nanoscale.In terms of catalytic properties,benefiting from intrinsically high activity of Co_(2)C NPs,the material demonstrates superior hydrogen evolution reaction(HER)performance,with optimal overpotential as low as 73 mV at the current density of 10 mA·cm^(-2).This provides new ideas for the further development of transition metal carbides(TMCs)and the improvement of their magnetic and electrocatalytic properties.
