20%唑胺菌酯悬浮剂在黄瓜和土壤中的消解动态及最终残留

[目的]通过2年3地的田间试验及残留检测,明确唑胺菌酯在黄瓜及土壤中的消解动态和最终残留量。[方法]消解动态试验按剂量300 g a.i./hm2施药1次;最终残留试验按300 g a.i./hm2(高剂量)和200 g a.i./hm2(低剂量)分别施药4、5次;采用高效液相色谱法对20%唑胺菌酯悬浮剂有效成分进行检测。[结果]2年3地的消解动态试验结果表明:唑胺菌酯在黄瓜和土壤中的消解半衰期分别为2.86~5.63、4.61~13.25 d。最终残留试验结果表明:唑胺菌酯在黄瓜和土壤中的最终残留量分别为0.020~0.380、0.020~1.134 mg/kg。[结论]建议唑胺菌酯在黄瓜中的最大残留限量为0.08 mg/kg;20%唑胺菌酯悬浮剂按其推荐剂量200 g a.i./hm2在黄瓜上施用4次,安全间隔期为3 d。     

腈菌唑在土壤中的残留分析及热带气候下消解动态

研究腈菌唑在土壤中的残留分析方法及其在土壤中热带气候下的消解动态和最终残留。土壤样品经乙腈萃取,净化后采用毛细管气相色谱法-氮磷检测器（GC-NPD）进行测定。方法检出限为0.008mg/kg,在0.20、1.00、2.00mg/kg三个添加水平,回收率为75.6%～94.6%,变异系数为2.7%～6.8%,符合农药残留分析的要求。运用上述方法,测定腈菌唑在热带气候下土壤中的消解动态和最终残留。结果表明,腈菌唑在土壤中小结速度较快,测得在土壤中半衰期2004年为17.0d,2005年为14.9d;以最大推荐施用剂量和2倍最大推荐施用剂量施用,不同处理测得在最后一次施药后20d残留量均小于1mg/kg。分析结果表明腈菌唑是一种使用安全的杀菌剂。     

氟菌唑在刺五加和土壤中的残留量及安全使用评价

[目的]研究30%氟菌唑可湿性粉剂在刺五加根、茎、叶和土壤中的残留动态研究及最终残留量,使氟菌唑在刺五加栽培中施药的使用更加合理和安全。[方法]试验采用高效液相色谱-串联质谱技术(HPLC-MS/MS),经丙酮提取样品,GPR固相萃取柱净化,采用电喷雾电离源,以质谱正离子扫描多反应监测模式进行定量分析,外标法定量。[结果]添加质量分数在0.005~0.050 mg/kg的范围内,氟菌唑在刺五加根、茎、叶及土壤中的回收率为72.3%~119.2%,相对标准偏差为1.4%~6.6%。其中,消解动态试验结果为施药剂量为300 ga.i./hm2时,氟菌唑在刺五加茎、叶和土壤中的降解半衰期为1.3~21.9 d。最终残留试验结果说明,在生长季节施药1次,施药剂量分别为150、300 g a.i./hm2,氟菌唑在刺五加根、茎、叶和土壤中的最终残留量分别为未检出至0.006 3 mg/kg,未检出至0.007 9 mg/kg,未检出至0.006 5 mg/kg和0.005 7~0.012 5 mg/kg,均处于安全水平。[结论]根据试验结果 ,建议我国氟菌唑在刺五加中的最大残留限量值(MRL)可暂定为0.05 mg/kg,安全间隔期为27 d。     

60%唑醚·代森联WG在大蒜及土壤中的残留

[目的]研究60%唑醚.代森联WG在大蒜、植株、土壤中的残留及消解动态。[结果]吡唑醚菌酯和代森联(CS2计)的最小检出量分别为4×10-10、4×10-11g,在样品中的最低检出质量分数分别为0.02、0.04 mg/kg。试验结果表明吡唑醚菌酯和代森联在植株和土壤中的半衰期分别为2.6～3.2、9.0～10.5 d和2.8～3.6、3.1～4.1 d。60%唑醚.代森联WG以900、1350 g a.i./hm2对水喷雾,连喷3～4次,施药间隔期7 d,最后1次施药后7 d大蒜中吡唑醚菌酯、CS2均未检出。[结论]推荐60%唑醚.代森联WG在大蒜上使用安全间隔期为7 d。     

菠菜中噻虫嗪的残留检测与消解动态

采用高效液相色谱分析技术测定了噻虫嗪在菠菜中的残留动态和最终残留.噻虫嗪的最低检出量为1 ng,最低检出质量分数为0.002 mg/kg.在菠菜中的平均回收率为90.5%～101.4%,相对标准偏差0.75%～1.21%.噻虫嗪在土壤和菠菜中的半衰期分别为2.3 d.按180 g/hm2剂量施药3 d后,菠菜中最高残留量为0.55 mg/kg.     

氟硅唑乳油在葡萄和土壤中的残留动态

为评价氟硅唑在葡萄上使用后的残留动态及环境安全性,在北京和长春市郊区进行了其在葡萄上的残留动态和最终残留试验.葡萄和土壤样品用丙酮提取,液液分配净化,用带紫外检测器的液相色谱测定了其残留量.氟硅唑的最低检出量为3.0×10-11g,在葡萄和土壤中的最低检出质量分数均为0.01 mg/kg.在葡萄和土壤中的平均回收率为92.6%～99.0%,变异系数为1.7%～13.3%,符合农药残留分析的要求.研究结果表明,氟硅唑在葡萄上的半衰期为5.8～7.0 d,在土壤中的半衰期为12.0～14.0 d.40%氟硅唑EC按推荐剂量0.05 g a.i./kg和推荐剂量的2倍0.1 g a.i./kg使用3、4次,末次施药距收获间隔28、35 d,氟硅唑在葡萄中的残留量为0.084～0.216 mg/kg,土壤中为0.025～0.318 mg/kg,残留量低于FAO规定的氟硅唑在葡萄中的MRL值0.5 mg/kg,所以40%氟硅唑EC按推荐剂量0.05 g a.i./kg在葡萄上使用3次,末次施药距收获间隔28 d,收获的葡萄是安全的.     

腈菌唑在大葱中的残留分析与消解动态

[目的]腈菌唑被认为是防治大葱锈病等病害应用前景较好的杀菌剂,但尚未见腈菌唑在大葱中残留检测方法和残留消解动态的研究报道,建立腈菌唑在大葱中残留检测方法和残留消解动态的方法.[方法]采用气相色谱质谱法(GC-MS)测定了腈菌唑在春季大葱中的残留消解动态和最终残留量.样品经乙腈提取,SAX/PSA固相萃取柱净化,气相色谱质谱选择离子(GC/MS/SIM)检测.[结果]建立的大葱中腈菌唑残留量检测方法在0.01～0.10 mg/kg水平的平均添加回收率为93.0%～107.9%,相对标准偏差为2.1%～5.6%,腈菌唑检测限为0.002 mg/kg.腈菌唑在大葱中消解较快,半衰期为3.4 d.12.5%腈菌唑乳油按推荐剂量(62.5 mg a.i./kg)和加倍剂量(125.0 mg a.i./kg)对水喷雾2-3次,末次施药后7、14 d腈菌唑在大葱中残留量为0.003～0.017 mg/kg.[结论]建立的大葱中腈菌唑残留检测方法准确可靠.大葱收获时最终残留量低于日本规定的最大允许残留量(MRL),满足出口国要求.     

仲丁灵在土壤中的消解动态研究

采用气相色谱法建立了仲丁灵在土壤中的残留分析测定方法,并试验了仲丁灵在土壤中的残留消解动态。样品采用丙酮提取,经弗罗里硅土柱净化后,采用气相色谱法测定。该方法的添加回收率为90.71%～99.06%,变异系数为0.89%～3.34%,最低检出浓度为0.05 mg/kg,最低检出量为1.89×10-10g。消解动态试验结果表明,仲丁灵按推荐使用剂量(1 800 g/hm2)和2倍推荐使用剂量(3 600 g/hm2)施药,它在土壤中的半衰期分别为9.04 d和11.17 d。     

精甲霜灵在西瓜和土壤中的残留动态

采用液相色谱测定了精甲霜灵在西瓜及土壤中的残留动态和最终残留量.精甲霜灵的最低检出量为0.5 ng,最低检出质量分数为0.02 mg/kg.在西瓜全瓜、瓜瓤和土壤中的平均同收率为80.8%～90.1%,相对标准偏差2.9%～6.7%.结果表明:精甲霜灵在西瓜中的半衰期为3.2～3.5 d;在土壤中的半衰期为9.0～10.7 d.440 g/L精甲霜灵·百菌清悬浮剂按照推荐用量990 g a.i./hm2和推荐用量的1.5倍(1485 g a.i./hm2)施药3～4次,末次施药5 d后,西瓜瓜瓤中的精甲霜灵残留量低于0.2 mg/kg.     

春雷霉素在水稻上的残留与消解动态研究

为了评价春雷霉素在水稻上使用的安全性,建立其使用规范,2010-2011年在河南、黑龙江和江苏3地进行了10%春雷霉素可湿性粉剂在水稻上的消解动态和最终残留试验。消解动态试验结果表明:春雷霉素在水稻田水和植株中的半衰期分别为0.97².70 d和1.002.70 d和1.00².18 d。最终残留试验表明:10%春雷霉素可湿性粉剂按推荐剂量(40 g/hm2)和1.5倍推荐剂量(60 g/hm2)在病害发生期施药32.18 d。最终残留试验表明:10%春雷霉素可湿性粉剂按推荐剂量(40 g/hm2)和1.5倍推荐剂量(60 g/hm2)在病害发生期施药3⁴次,末次施药后14,21,28 d,春雷霉素在糙米中残留量≤0.022 mg/kg,稻壳中≤0.269 mg/kg,植株中≤0.159 mg/kg,土壤中≤0.005 mg/kg。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.