目的：优化蟾酥聚合物胶束的制备工艺。方法：采用薄膜分散-微射流法,以普郎尼克F123和脱氧胆酸钠为聚合物胶束的载体材料,以包封率为主要考察指标,通过星点-效应面法,以F123和脱氧胆酸钠质量比、蟾酥和载体的质量比、水化体积、微射流...目的：优化蟾酥聚合物胶束的制备工艺。方法：采用薄膜分散-微射流法,以普郎尼克F123和脱氧胆酸钠为聚合物胶束的载体材料,以包封率为主要考察指标,通过星点-效应面法,以F123和脱氧胆酸钠质量比、蟾酥和载体的质量比、水化体积、微射流压力、循环次数为主要考察因素,优化蟾酥聚合物胶束的制备工艺。结果：蟾酥聚合物胶束制备的最佳工艺为：F123和脱氧胆酸钠质量比为1.5∶1,蟾酥和载体的质量比为45∶1,水化体积为9 m L,微射流压力为120 MPa,循环次数为7次;蟾酥聚合物胶束在透射电镜下观察呈类球形,平均粒径为120 nm,包封率为94.12%,载药量为0.14%。结论：该制备工艺稳定可行,重复性好,可用于蟾酥聚合物胶束的制备。展开更多
The influence of oxygen supply mode on the KIVCET (a Russian acronym for flash?cyclone?oxygen?electric?smelting) process was investigated using numerical simulation. The mass rate ratio (MRR) of central oxygen to late...The influence of oxygen supply mode on the KIVCET (a Russian acronym for flash?cyclone?oxygen?electric?smelting) process was investigated using numerical simulation. The mass rate ratio (MRR) of central oxygen to lateral oxygen of the central jet distributor (CJD) burner was defined to express the oxygen supply mode, and the KIVCET process with an MRR ranging from 0.09 to 0.39 was simulated. The results show that there are four efficient reaction regions that correspond to four CJD burners. A higher central oxygen flow improves the mixing between particles and oxygen, thus enhancing reactions and shortening the reaction regions. However, a higher dust rate is induced due to the spread of the particle columns. The optimal MRR for a KIVCET furnace with a smelting capacity of 50000 kg/h is suggested to be 0.31. In this case, the chemical reactions associated with the feed are completed with an acceptable dust rate.展开更多
In order to reveal the influence of forced ventilation on the dispersion of droplets ejected from roadheader-mounted external sprayer,the paper studies the air-flowing field and the droplet distribution under the cond...In order to reveal the influence of forced ventilation on the dispersion of droplets ejected from roadheader-mounted external sprayer,the paper studies the air-flowing field and the droplet distribution under the condition of gentle breeze and normal forced ventilation in heading face using the particle tracking technology of computational fluid dynamics(CFD).The results show that air-flowing tendency in the same section presents great comparability in the period of gentle breeze and forced ventilation,and the difference mainly embodies in the different wind velocity.The influence of ventilation on the dispersion of droplets is faint under the gentle breeze condition.The droplet can be evenly distributed around the cutting head.However,under the normal forced ventilation,a large number of droplets will drift to the return air side.At the same time,droplet clusters are predominantly presented in the lower part of windward side and the middle of the leeward side around the cutting head.In contrast,the droplet concentration in other parts around cutting head decreases a lot and the droplets are unable to form close-grained mist curtain.So the dust escape channel is formed.In addition,the simulation results also reveal that the disturbance of air flow on the droplet distribution can be effectively relieved when using ventilation duct with Coanda effect(VDCE).Field experiment results show that the dust suppression efficiency of total dust and respirable dust increases respectively by 10.5%and 9.3%when using VDCE,which proves that it can weaken the influence of airflow on droplet dispersion.展开更多
We have investigated the properties of cellulose diacetate in solution by using laser light scattering. The cellulose diacetate molecules can form micelles and micellar clusters in acetone besides the individual chain...We have investigated the properties of cellulose diacetate in solution by using laser light scattering. The cellulose diacetate molecules can form micelles and micellar clusters in acetone besides the individual chains. As the concentration increases, the average hydrodynamic radius （Rh） linearly increases, whereas the ratio of gyration radius to hydrodynamic radins 〈Rg〉/〈Rh〉 linearly decreases. It indicates that the micelles associate and form micellar clusters due to the intermolecular interactions.展开更多
文摘目的：优化蟾酥聚合物胶束的制备工艺。方法：采用薄膜分散-微射流法,以普郎尼克F123和脱氧胆酸钠为聚合物胶束的载体材料,以包封率为主要考察指标,通过星点-效应面法,以F123和脱氧胆酸钠质量比、蟾酥和载体的质量比、水化体积、微射流压力、循环次数为主要考察因素,优化蟾酥聚合物胶束的制备工艺。结果：蟾酥聚合物胶束制备的最佳工艺为：F123和脱氧胆酸钠质量比为1.5∶1,蟾酥和载体的质量比为45∶1,水化体积为9 m L,微射流压力为120 MPa,循环次数为7次;蟾酥聚合物胶束在透射电镜下观察呈类球形,平均粒径为120 nm,包封率为94.12%,载药量为0.14%。结论：该制备工艺稳定可行,重复性好,可用于蟾酥聚合物胶束的制备。
基金Project(61621062)supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China
文摘The influence of oxygen supply mode on the KIVCET (a Russian acronym for flash?cyclone?oxygen?electric?smelting) process was investigated using numerical simulation. The mass rate ratio (MRR) of central oxygen to lateral oxygen of the central jet distributor (CJD) burner was defined to express the oxygen supply mode, and the KIVCET process with an MRR ranging from 0.09 to 0.39 was simulated. The results show that there are four efficient reaction regions that correspond to four CJD burners. A higher central oxygen flow improves the mixing between particles and oxygen, thus enhancing reactions and shortening the reaction regions. However, a higher dust rate is induced due to the spread of the particle columns. The optimal MRR for a KIVCET furnace with a smelting capacity of 50000 kg/h is suggested to be 0.31. In this case, the chemical reactions associated with the feed are completed with an acceptable dust rate.
基金supported by the Program for Postgraduates Research Innovation in University of Jiangsu Province of China (No.CXLX13_955)the National Natural Science Foundation of China (No.51104153)
文摘In order to reveal the influence of forced ventilation on the dispersion of droplets ejected from roadheader-mounted external sprayer,the paper studies the air-flowing field and the droplet distribution under the condition of gentle breeze and normal forced ventilation in heading face using the particle tracking technology of computational fluid dynamics(CFD).The results show that air-flowing tendency in the same section presents great comparability in the period of gentle breeze and forced ventilation,and the difference mainly embodies in the different wind velocity.The influence of ventilation on the dispersion of droplets is faint under the gentle breeze condition.The droplet can be evenly distributed around the cutting head.However,under the normal forced ventilation,a large number of droplets will drift to the return air side.At the same time,droplet clusters are predominantly presented in the lower part of windward side and the middle of the leeward side around the cutting head.In contrast,the droplet concentration in other parts around cutting head decreases a lot and the droplets are unable to form close-grained mist curtain.So the dust escape channel is formed.In addition,the simulation results also reveal that the disturbance of air flow on the droplet distribution can be effectively relieved when using ventilation duct with Coanda effect(VDCE).Field experiment results show that the dust suppression efficiency of total dust and respirable dust increases respectively by 10.5%and 9.3%when using VDCE,which proves that it can weaken the influence of airflow on droplet dispersion.
基金ACKNOWLEDGMENTS This work was supported by China Tobacco Guangdong Industrial Co., Ltd., National Natural Science Foundation of China （No21234003 and No.51303059）, and the Fundamental Research Funds for Central Universities.
文摘We have investigated the properties of cellulose diacetate in solution by using laser light scattering. The cellulose diacetate molecules can form micelles and micellar clusters in acetone besides the individual chains. As the concentration increases, the average hydrodynamic radius （Rh） linearly increases, whereas the ratio of gyration radius to hydrodynamic radins 〈Rg〉/〈Rh〉 linearly decreases. It indicates that the micelles associate and form micellar clusters due to the intermolecular interactions.
