叶片加料回潮工序对卷烟叶组化学成分的影响

运用现代分析技术分析叶片加料回潮工序对卷烟叶组及其制品的化学成分的变化规律。结果表明：叶片加料回潮工序对卷烟叶组的总氮、烟气一氧化碳释放量影响较大,其中总氮含量升高11%,而一氧化碳释放量则降低11%,焦油释放量、烟碱和一氧化碳均与总植物碱的相关性较强,其中焦油释放量与总植物碱呈负相关,烟碱和一氧化碳则与其呈正相关。     

连作晚稻前期施药种类和时间对褐飞虱种群动态的影响

 田间试验研究了连晚前期施药种类和时间对褐飞虱种群动态的影响。结果表明施药后褐飞虱种群数量均有不同程度下降，但对褐飞虱主害代的控制作用与使用的农药种类和时间有密切的关系，而农药对褐飞虱的控制作用随种群的发展而下降。施药区褐飞虱种群增长倍数较对照区显著提高，其主要原因是农药对天敌尤其是对微蛛和黑肩绿盲蝽的杀伤作用。引起褐飞虱种群增长倍数提高的主要时期在四代成、若虫高峰期至五代卵高峰期，即施药后2～3周内。在各种供试药剂中，施用三唑磷的小区明显出现再增猖獗现象．根据以上结果，讨论了改善褐飞虱化学防治的途径。     

An index for selective toxicity of miticides to phytophagous mites and their predators based on orchard trials

Data from nine trials conducted from 1990 to 1998 in apple orchards in Nova Scotia and Quebec, Canada, were used to estimate the predator-prey selectivity of miticides and their potential compatibility with biological control of mites. The European red mite Panonychus ulmi (Koch) was the dominant and more harmful phytophagous species, followed by the apple rust mite, Aculus schlechtendali (Nalepa). Two predacious mites, the phytoseiid, Typhlodromus pyri Sheuten, and the stigmaeid, Zetzellia mali (Ewing), were often found in the orchards. We used one minus the ratio of mite-days in treated plots to those in the control plots as an index of population suppression and toxicity of the miticides. Miticides were then categorized into classes similar to those employed by the International Organization for Biological Control to rate pesticide toxicity to natural enemies of insect and mite pests. Selectivity of miticides was mostly based on toxicity to P ulmi, the major pest, versus toxicity to T pyri, the major predator, with some consideration of the two lesser species, A schlechtendali and Z mali. In most cases, our findings were in accord with other studies. Abamectin and clofentezine had favourable selectivity (more toxic to the two phytophagous mites than to T pyri). The higher recommended rate of pyridaben (450 g ha(-1)) and two rates of spirodiclofen (180 and 240 g ha(-1)) were neutral (equally toxic to pests and predators). The lower rate of pyridaben (216 g ha(-1)), dicofol, formetanate hydrochloride and propargite were unfavourably selective (more toxic to T pyri). A higher than recommended rate of pyridaben (2160 g ha(-1)) applied before bloom was disruptive--P ulmi-days after treatment were actually greater than with the untreated control. P ulmi resistance to dicofol and propargite were probable complicating factors in some of the orchard trials.     

棉花蚜螨繁殖率及棉蚜再猖獗

氰戊菊酯曾对棉蚜有极好的防治效果,而对棉叶螨防治效果极差。棉蚜抗药性的发展使药效发生了变化,近来的试验表明,该药对蚜虫药效很差,对伏蚜根本无效,１００和２００ｐｐｍ对棉蚜已属低浓度,可使其繁殖率增加４－８倍,在田间使用氰戊菊酯可形成大的棉蚜群体。在相同浓度下一般可抑制棉叶蚜群体,使药后存活很少的棉叶螨在种间竞争中处于劣势而使群体越来越小。氰戊菊酯的复配剂－丰收菊酯弥补了氰戊菊酯的不足,可同时控制蚜     

真空回潮工艺参数对烟叶香味物质含量的影响

[目的]研究真空回潮过程对烟叶中香味物质含量的影响。[方法]以WZ-003-YX型真空回潮机为研究对象,选择2个工作周期的抽空温度、加湿温度、保温时间等6个因素,采用均匀设计法设置了10种不同的工艺参数组合,对云南中烟某牌号配方烟叶进行处理,分别测定真空回潮前后烟叶中香味物质含量并对数据进行分析。[结果]试验表明,烟叶经过真空回潮处理后总香味物质含量显著升高,平均升高12.01μg/g,且这种变化趋势不受工艺参数的影响。[结论]研究可为卷烟生产加工中合理制定工艺条件提供参考。     

常用杀虫剂对稻田迁飞性害虫的控制作用及其对天敌的安全性评价

在稻纵卷叶螟和白背飞虱混发期对7个常用杀虫剂的控制作用及其对天敌的安全性进行了评价。结果表明,2.5%高效氯氟氰菊酯EC(30 ml/667 m2) 70%艾美乐(吡虫啉)WG(7.14 g/667 m2)处理和31%三拂(三唑磷 氟虫腈)ME(70 ml/667 m2)对稻纵卷叶螟和白背飞虱均具有较强的控制效果。但是高效氯氟氰菊酯、锐劲特(5%氟虫腈)、高效氯氟氰菊酯 艾美乐和三拂均对主要蜘蛛有较强的杀伤作用,而三唑磷和新农宝(40%毒死蜱)对蜘蛛相对安全。高效氯氟氰菊酯和三唑磷单剂对白背飞虱和褐飞虱均具有明显的增殖作用,但可通过与锐劲特混配减轻增殖效应。因此,在田间稻纵卷叶螟和稻飞虱兼发的情况下,推荐使用三拂进行兼治,以减少杀虫剂的用药次数、药量及其对稻飞虱的增殖效应。     

烟梗回潮工艺对梗丝物理及烟气指标影响的研究

[目的]系统评价不同烟梗回潮工艺对梗丝物理和烟气指标的影响情况.[方法]通过对比检测分析常压烟梗回潮工艺与高压蒸梗工艺不同压力条件下处理的梗丝的物理指标和烟气指标.[结果]试验得出,高压蒸梗处理梗丝的整丝率低于常压处理梗丝,随着高压处理压力的增加、蒸汽温度的增加,梗丝整丝率呈现下降趋势;高压蒸梗低压润梗梗丝填充值与常压处理下差异较小,随着高压处理压力的增加、蒸汽温度的增加,梗丝填充值呈现下降趋势;高压蒸梗工艺储梗后梗丝填充值略有降低,整丝率略有提升;高压蒸梗工艺梗丝的焦油释放量、CO释放量高于常压处理梗丝,随着高压处理压力的增加、蒸汽温度的增加,焦油及CO释放量呈现上升趋势.[结论]研究可为合理选择烟梗回潮工艺提供理论依据.     

SIEMENS可编程控制器在WQ822型水槽式烟梗回潮机自动控制中的应用

针对WQ822型水槽式烟梗回潮机使用一段时间以后出现供水不稳定和蒸汽控制不可靠的问题，根据工艺要求利用STEP7软件重新编程，实现了水位和水温的连续稳定和可靠运行．     

基于热力学的烟叶回潮机优化设计试验研究

提高烤后烟叶含水率和温度,保证烟叶质量,需要对烟叶进行回潮处理。回潮箱体内温度梯度小、流场分布均匀,可以有效保证不同位置的烟叶含水率一致。本文以热力学理论为基础,利用COMSOL Multiphysics多物理场仿真软件,对回潮箱体内的温度场、流场进行仿真分析。试验发现:回潮后箱体内不同位置的烟叶含水率变化小于0.5%。结果表明:优化设计的回潮箱体性能可靠,流场分布均匀,能够满足烟叶回潮要求。