The way of producing needle-shaped wolldstonite pow-der has never been released, the key to the matter is to get high enough length to -width ratio of the particle. With φ 50 mm horizontal disk type jet mill,rue carr...The way of producing needle-shaped wolldstonite pow-der has never been released, the key to the matter is to get high enough length to -width ratio of the particle. With φ 50 mm horizontal disk type jet mill,rue carry out a series of experiments, and discover that select-ing reasonable technological operating condition, with the aim of weak-ening colliding pulverizing effect and reinforcing rubbing pulverizing effect, is helpful to improve effectively the L-W radio.展开更多
Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystall...Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.展开更多
利用山东省84个气象台站的逐日降水资料、美国国家环境预测中心和国家大气研究中心(National Centers for Environmental Prediction and National Center for Atmospheric Research, NCEP/NCAR)逐日再分析资料以及中国气象局(CMA)热带...利用山东省84个气象台站的逐日降水资料、美国国家环境预测中心和国家大气研究中心(National Centers for Environmental Prediction and National Center for Atmospheric Research, NCEP/NCAR)逐日再分析资料以及中国气象局(CMA)热带气旋资料中心的CMA最佳路径数据集,对1969—2020年夏季(6—8月)发生在山东的857例极端暴雨事件(Extreme rainstorm events, EREs)的时空分布特征及影响环流分型进行了分析。结果表明:山东夏季EREs主要集中在7和8月,8月极端暴雨降水量占当月总降水量的比值最大,可达53.5%。山东夏季极端暴雨降水量以及极端暴雨发生日数呈现不显著的增加趋势,8月的增加趋势最明显。使用经验正交函数分解对影响山东夏季EREs的大气环流系统进行分型,发现影响山东夏季出现EREs的环流系统主要有4类,其中,影响ERE最多的环流系统是北方气旋型,约占事件总频次的33.1%;其次是高空急流型,占比约11.3%;南方气旋型和热带气旋型的环流型影响相当,出现的概率分别为9.7%和9.4%。展开更多
Ultrasonic and jet combined process was studied to remove determined by static experiments, and stability of this combined process algae in lake type raw water. The optimum reaction time was was checked by dynamic exp...Ultrasonic and jet combined process was studied to remove determined by static experiments, and stability of this combined process algae in lake type raw water. The optimum reaction time was was checked by dynamic experiments. The results was showed that ultrasonic/jet combined process has excellent removal efficiency on algae in lake type raw water, and it＇s a simple operation, and has no secondary pollution. When the pH, temperature, chlorophyll-a（Chl-a） and cell concentration（OD560） of raw water are 7.69, 25.8 ℃, 29.003 mg/m^3 and 0.091, the average removal efficiency on Chl-a and OD560 are 81.60% and 80.22%, respectively, which are stable by this combined process when it is operating in 36 hours, and samples are analyzed each 4 hours.展开更多
文摘The way of producing needle-shaped wolldstonite pow-der has never been released, the key to the matter is to get high enough length to -width ratio of the particle. With φ 50 mm horizontal disk type jet mill,rue carry out a series of experiments, and discover that select-ing reasonable technological operating condition, with the aim of weak-ening colliding pulverizing effect and reinforcing rubbing pulverizing effect, is helpful to improve effectively the L-W radio.
文摘Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.
文摘利用山东省84个气象台站的逐日降水资料、美国国家环境预测中心和国家大气研究中心(National Centers for Environmental Prediction and National Center for Atmospheric Research, NCEP/NCAR)逐日再分析资料以及中国气象局(CMA)热带气旋资料中心的CMA最佳路径数据集,对1969—2020年夏季(6—8月)发生在山东的857例极端暴雨事件(Extreme rainstorm events, EREs)的时空分布特征及影响环流分型进行了分析。结果表明:山东夏季EREs主要集中在7和8月,8月极端暴雨降水量占当月总降水量的比值最大,可达53.5%。山东夏季极端暴雨降水量以及极端暴雨发生日数呈现不显著的增加趋势,8月的增加趋势最明显。使用经验正交函数分解对影响山东夏季EREs的大气环流系统进行分型,发现影响山东夏季出现EREs的环流系统主要有4类,其中,影响ERE最多的环流系统是北方气旋型,约占事件总频次的33.1%;其次是高空急流型,占比约11.3%;南方气旋型和热带气旋型的环流型影响相当,出现的概率分别为9.7%和9.4%。
文摘Ultrasonic and jet combined process was studied to remove determined by static experiments, and stability of this combined process algae in lake type raw water. The optimum reaction time was was checked by dynamic experiments. The results was showed that ultrasonic/jet combined process has excellent removal efficiency on algae in lake type raw water, and it＇s a simple operation, and has no secondary pollution. When the pH, temperature, chlorophyll-a（Chl-a） and cell concentration（OD560） of raw water are 7.69, 25.8 ℃, 29.003 mg/m^3 and 0.091, the average removal efficiency on Chl-a and OD560 are 81.60% and 80.22%, respectively, which are stable by this combined process when it is operating in 36 hours, and samples are analyzed each 4 hours.
