共查询到17条相似文献,搜索用时 234 毫秒
1.
2.
通过比较分析3种不同实仓施药方式硫酰氟熏蒸高大平房仓的穿透力、均匀性和杀虫效果,探索硫酰氟在实仓熏蒸的最佳工艺。结果表明,硫酰氟气体可在2.5 h内自然扩散穿透粮堆,24 h左右达到整仓基本均匀。环流熏蒸可以加速气体均匀,但此次实验环流过程中导致了一定药剂损失。在整仓熏蒸、膜下上行环流和膜下下行环流的3种熏蒸方式中,整仓熏蒸操作最为简便,可用于快速杀灭成虫;膜下上行环流方式,药剂损耗量较大;膜下下行环流,浓度均匀速度快,用药量较整仓小,药剂浓度保持时间长,杀虫效果好。 相似文献
3.
4.
5.
6.
7.
8.
9.
10.
11.
研究了我国华南地区广州岭南穗粮谷物股份有限公司一面粉加工车间B区、C区,长为108 m,宽为25 m,高为35.2 m,总体积为95 040 m3,有效熏蒸体积为53842 m3的空间,采用硫酰氟剂量为40 g/m3、密闭时间为48 h的整体性结构熏蒸。在不补充硫酰氟熏蒸剂的条件下,熏蒸过程浓度随时间变化的规律,建立了熏蒸剂的日损失率Ld和浓度半数衰减时间HLT,分析了各楼层硫酰氟浓度变化规律和熏蒸剂泄漏程度,评估了杀虫效果。熏蒸剂的日损失率符合模型:(e,自然常数;b,衰减常数),浓度半数衰减时间HLT符合模型:熏蒸剂日损失率的变化随着衰减常数的增大而增大,浓度半数衰减时间HLT的变化随着衰减常数的增大而减小。单次熏蒸时衰减常数为固定值,熏蒸剂日损失率、浓度半数衰减时间HLT为恒定变化。经模型评估,6、7、8楼的日损失率Ld和半数衰减时间介于56.7 %~71.3 %和0.56~0.83 d。3、4楼区域损失率Ld和半数衰减时间介于85.0 %~92.6 %和0.27~0.37 d;除8楼硫酰氟熏蒸剂浓度半数衰减时间HLT超过15 h,其余楼层均未超过15 h。熏蒸后22 d,取样检测发现面粉加工车间设备和管道中均发现赤拟谷盗幼虫活虫。采用硫酰氟进行建筑物结构40 g/m3剂量、密闭时间48 h方式熏蒸,可将车间空间区域害虫各虫态以及管道和设备中成虫杀死,存在于设备和管道内的卵可能存活且发育成新幼虫或蛹。 相似文献
12.
为了解不同气密性仓房硫酰氟熏蒸过程中的浓度衰减规律,选取5个不同气密性储粮仓房,通过熏蒸过程中的硫酰氟浓度监测,分析和比较气体浓度衰减半衰期和仓房气密性的相关性。结果显示,当仓房气密性为143 s时,最长浓度半衰期为8.5 d;当仓房气密性为53、46 s时,最高浓度半衰期分别为2.7、4.6 d。无法检测出气密性的仓房气体浓度半衰期约在2~3 d。硫酰氟气体浓度越高,衰减速度越快,但研究并未发现气体浓度衰减与仓房气密性呈现明显规律。 相似文献
13.
本研究通过膜下环流熏蒸、氮气气调、氮气与磷化氢混合熏蒸三种熏蒸方式,来分析在高大平方仓中这三种方式施药后,熏蒸气体的空间浓度分布情况。结果表明,覆膜环流熏蒸仓房底部磷化氢浓度在第3 d达到最大,较常规熏蒸快2~4 d。氮气和磷化氢混合熏蒸在环流6 h后各层粮堆内气体分布基本达到均匀,整个熏蒸过程中磷化氢最低浓度与最高浓度的比值范围为0.37~0.67,氮气浓度始终保持在83%~87%之间。混合熏蒸与膜下环流熏蒸相比,可以减少用药量10.8%;同时,解决了氮气气调对气密性要求严苛以及运营成本高的难题,供粮食仓储企业在实际熏蒸杀虫工作中参考。 相似文献
14.
A comparison between the impact of sulfuryl fluoride and methyl bromide fumigations on stored-product insect populations in UK flour mills 总被引:1,自引:0,他引:1
The impact of sulfuryl fluoride and methyl bromide fumigations upon populations of flour beetles (Tribolium spp.) and of Mediterranean flour moth (Ephestia kuehniella), was evaluated in UK flour mills. Two mills were selected for fumigation with sulfuryl fluoride and two mills for fumigation with methyl bromide. Traps baited with aggregation pheromone lure and an oil-based food attractant were used to monitor populations of rust red flour beetle and confused flour beetle. For the monitoring of Mediterranean flour moth, sticky traps baited with a pheromone lure were used. Traps were placed inside the mill buildings within the areas selected for fumigation. Infestation levels of the insects were monitored for 1–2 weeks prior to fumigation and for a total of 12 weeks post-fumigation. From the calculated percentage reduction in insects trapped per day during the post-fumigation monitoring period it was clear that sulfuryl fluoride fumigations had good efficacy against infestations of Tribolium confusum and E. kuehniella, and compared very favourably with the efficacy of methyl bromide. The absence of T. castaneum in traps pre-fumigation meant that the efficacy of sulfuryl fluoride against this species could not be assessed in this investigation. Indian meal moth, Plodia interpunctella, was also detected in some mills but only post-fumigation. 相似文献
15.
Preliminary field trials using red oak logs from trees dying from oak wilt disease were successful in eliminating the oak
wilt fungus from sapwood after fumigation with sulfuryl fluoride for 72 h under tarp. These results support earlier laboratory
data on the fungitoxicity of sulfuryl fluoride as a potential replacement for methyl bromide treatment of exported red oak
veneer logs. However, not all other microorganisms were completely eradicated from oak sapwood at the treatment levels used
in this trial.
相似文献
16.
A validated Computational Fluid Dynamics (CFD) model of structural fumigation was used to perform 54 fumigation simulations (half with sulfuryl fluoride, SF, and half with methyl bromide, MB) using recorded hourly average weather data for 4 July and 1 September at Indianapolis International Airport for the years 1996-2006. These weather data were used as the simulation boundary conditions. Although the fumigations were simulated for the same time periods, the results indicated substantial variations in the fumigant leakage rates. The 11-year averages of wind speeds on 4 July and 1 September were 3.8 and 2.4 m/s, respectively, resulting in half-loss time (HLT) differences between the fumigations on the two days. On average, the HLT was 4 h lower on 4 July than on 1 September. When comparing the results between individual fumigations, substantial differences in the fumigant leakage were observed, regardless of the fumigant type and whether or not the fumigations were performed at the same time period. This implied that using past fumigation data as the primary means for evaluating the structural sealing quality of a current fumigation is not adequate. Predictions of fumigant leakage rate and fumigation performance should incorporate quantifiable sealing effectiveness and weather information for the planned fumigation period. Comparisons between SF and MB fumigations indicated that under exactly the same weather conditions and fumigation practices the leakage characteristics of SF and MB do not differ. In practical situations where the dosage requirements for SF and MB are typically not the same, however, the leakage rates of SF and MB fumigations could be different due to the buoyancy effect. Nevertheless, the magnitude of the difference may or may not be significant depending on other factors such as sealing quality, wind speed and direction, and ambient temperature. The effects of these factors should be further quantified. 相似文献
17.
近年来由于熏蒸散气而产生的仓内安全事故引起了行业乃至社会各方的高度关注,但熏蒸散气阶段的作业安全研究较少,相关隐患尚未被深入研究以及重视。在实仓实验中,对高大平房仓磷化氢熏蒸和散气过程仓房内外环境空气中磷化氢浓度进行现场检测,探讨熏蒸、散气作业过程的有效安全防护距离以及防护措施,研究结果为防范熏蒸作业安全事故、减少或避免发生人身伤害和经济损失提供依据。研究结果表明,安全防护距离与仓内(粮堆内)磷化氢气体浓度大小有关,不能完全以固定的安全防护距离作为判定是否安全的依据,接近熏蒸散气区域前必须检测磷化氢浓度。 相似文献