为解决辊式筛砂机筛分过程中存在的振筛筛孔易堵塞、碎烟杂物筛净率低等问题,对辊式筛砂机进行了改进。改进后采用轮式辊道筛替代原辊道筛,取消二次筛分振筛。在筛砂过程中,固定筛孔的长度和宽度,避免来料烟叶中大规格烟片被筛出,使风...为解决辊式筛砂机筛分过程中存在的振筛筛孔易堵塞、碎烟杂物筛净率低等问题,对辊式筛砂机进行了改进。改进后采用轮式辊道筛替代原辊道筛,取消二次筛分振筛。在筛砂过程中,固定筛孔的长度和宽度,避免来料烟叶中大规格烟片被筛出,使风分分离后的碎烟片符合后续工序的要求。结果表明:改进后碎烟杂物平均筛净率提高54.3百分点,碎烟杂物返回烟叶主线的再加工量降低至0,风分获取的碎烟片量提高271.3%,风分去除的烟梗、砂土杂物量提高333.3%,电耗降低79.2 k W·h/d。改进后简化了筛砂机工艺流程,有效提高了筛砂机的筛砂效果。展开更多
This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It i...This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It is found that ametryn was the most effective herbicide that inhibited algal growth. Ametryn concentration that caused 50% inhibition on algae growth after exposure for 21 days was 0.335 ppm. Survival rate of oruamental fish, Harlequin rasbora （Trigonostigma heteromorpha） and growth rate of aquatic plant （Elodea canadensis） exposed to 10 ppm ametryn were compared with those exposed to algaecide. The result showed that there was no significant difference in survival rate of Harlequin rasbora when exposed to ametryn, algaecide and dechlorinized tap water （control）. However, growth rate of E. canadensis was lower after exposure of ametryn compared to those exposed to algaecide and tap water. These results suggest that ametryn has potential to be used as an algal inhibitor in aquarium.展开更多
文摘为解决辊式筛砂机筛分过程中存在的振筛筛孔易堵塞、碎烟杂物筛净率低等问题,对辊式筛砂机进行了改进。改进后采用轮式辊道筛替代原辊道筛,取消二次筛分振筛。在筛砂过程中,固定筛孔的长度和宽度,避免来料烟叶中大规格烟片被筛出,使风分分离后的碎烟片符合后续工序的要求。结果表明:改进后碎烟杂物平均筛净率提高54.3百分点,碎烟杂物返回烟叶主线的再加工量降低至0,风分获取的碎烟片量提高271.3%,风分去除的烟梗、砂土杂物量提高333.3%,电耗降低79.2 k W·h/d。改进后简化了筛砂机工艺流程,有效提高了筛砂机的筛砂效果。
文摘This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It is found that ametryn was the most effective herbicide that inhibited algal growth. Ametryn concentration that caused 50% inhibition on algae growth after exposure for 21 days was 0.335 ppm. Survival rate of oruamental fish, Harlequin rasbora （Trigonostigma heteromorpha） and growth rate of aquatic plant （Elodea canadensis） exposed to 10 ppm ametryn were compared with those exposed to algaecide. The result showed that there was no significant difference in survival rate of Harlequin rasbora when exposed to ametryn, algaecide and dechlorinized tap water （control）. However, growth rate of E. canadensis was lower after exposure of ametryn compared to those exposed to algaecide and tap water. These results suggest that ametryn has potential to be used as an algal inhibitor in aquarium.
