三种农药对中华大蟾蜍蝌蚪的急性毒性效应

农药的广泛使用是导致全球两栖动物种群衰退的主要因素之一。本实验以中华大蟾蜍(Bufo gargarizans)蝌蚪为实验材料,研究了甲基硫菌灵,高效氯氟氰菊酯,吡虫啉对中华大蟾蜍的急性毒性效应。实验结果表明,甲基硫菌灵、高效氯氟氰菊酯、吡虫啉对中华大蟾蜍(Bufo gargarizans)蝌蚪的96h半致死浓度(96h-LC50)分别为4.06 mg/L、9.84 mg/L、358.71 mg/L,安全浓度分别为0.041 mg/L、0.121 mg/L、3.58 mg/L。该结果对于进一步研究上述农药对中华大蟾蜍的慢性毒性效应奠定了基础。     

22%噻虫嗪·高效氯氟氰菊酯悬浮剂对环境非靶标生物的急性毒性与风险评估

建立了基于UPLC-MS/MS法测定曝气自来水和BG11培养基中噻虫嗪、高效氯氟氰菊酯的定性定量分析方法,测定了22%噻虫嗪·高效氯氟氰菊酯悬浮剂对环境5种非靶标生物的毒性并分级。结果表明,22%噻虫嗪·高效氯氟氰菊酯悬浮剂对斑马鱼、大型溞和家蚕的毒性为剧毒;对蜜蜂的毒性为高毒;分别以生长率抑制率和生物量增长抑制率为毒性终点计时,对羊角月牙藻的毒性分别为低毒和中毒。22%噻虫嗪·高效氯氟氰菊酯悬浮剂对蜜蜂和家蚕均存在潜在风险。建议实际施用过程注意周围开花植物花期,蚕室及桑园附近禁用。     

4种农药对意大利蜜蜂的毒力测定

利用摄入法测定联苯菊酯、溴氰菊酯、双甲脒和氟胺氰菊酯对意大利蜜蜂工蜂的毒性。结果表明,4种农药对意大利蜜蜂工蜂的LC50分别为16.263、62.900、302.784、1001.755mg/L。     

含溴农药生产状况与机会(二)

介绍了四溴菊酯、溴氟菊酯、除尽、溴甲烷、溴螨酯、溴敌隆、溴鼠隆、溴菌清、溴硝醇、苯扎溴胺、氯溴异氰尿酸、溴苯腈的应用领域、毒性和生产厂家。对杀虫杀螨剂、杀菌剂和除草剂的市场机会进行了分析,指出溴苯腈是一个值得关注的农药品种。     

避蚊酯的毒性试验

研究了避蚊酯原药的急性和亚慢性毒性及致突变性。结果显示:大鼠经口LD50雌性为10000mg/kg,雄性为12100mg/kg,大鼠经皮LD50雌雄性均大于2000mg/kg。家兔急性皮肤刺激试验,对皮肤的刺激强度属无刺激性。家兔眼刺激试验,对眼的刺激强度属中度刺激性。小鼠骨髓多染红细胞微核试验和小鼠睾丸精母细胞染色体畸变试验均为阴性。大鼠亚慢性经口毒性试验,对体重、摄食量、食物利用率、血液指标及血液生化指标均无明显影响,11000mg/kg饲料组雌性大鼠肾/体比、雄性大鼠肝/体比可见增高。病理检查发现,11000mg/kg饲料组4只大鼠可见肝脏1￣2个小炎症灶,2只大鼠少数肾小管上皮细胞肿胀。最大无作用剂量为:雌性大鼠393.67±26.98mg/kg·d,雄性大鼠336.65±26.38mg/kg·d。     

红肠片药膜法测定药剂对红火蚁的诱杀毒力

利用红肠片药膜法在田间开展了红火蚁的杀虫剂毒力测定。高效氯氟氰菊酯、呋虫胺、高效氯氰菊酯和溴虫氟苯双酰表现出很好的毒力,LC₅₀值分别为9.631、10.139、10.393 mg/L和16.391mg/L。多杀霉素、毒死蜱和茚虫威也表现出了良好的毒力。该毒力测定方法简化了红火蚁取样,缩短了毒力测定时间,有利于快速筛选红火蚁的有效防治药剂。     

生物农药阿维菌素的NEL和ADI研究

研究了阿维菌素原药的急性和亚慢性毒性及致突变性。结果显示,大鼠经口LD50雌雄性均为21.5mg/kg,小鼠经口LD50雌性为68.1mg/kg,雄性为38.3mg/kg,大鼠经皮LD50雌雄性均大于2000mg/kg。家兔急性皮肤刺激试验,对皮肤的刺激强度属无刺激性。家兔眼刺激试验,对眼的刺激强度属轻度刺激性。小鼠骨髓多染红细胞微核试验和小鼠睾丸精母细胞染色体畸变试验均为阴性。大鼠亚慢性经口毒性试验,21.5mg/kg饲料组雌性大鼠体重增加量低于对照组,雌雄性大鼠食物利用率低于对照组,雌雄性大鼠心/体比、肺/体比、肾/体比高于对照组,雌性大鼠脑/体比高于对照组,雄性大鼠脾/体比低于对照组,雌雄性大鼠血液生化指标ALB、GLU高于对照组。最大无作用剂量(NEL)为:雌性大鼠(0.796±0.062)mg/kg·d,雄性大鼠(0.635±0.056)mg/kg·d。若以安全系数100倍考虑,人的每日允许摄入量(ADI)应为0.0058mg/kg·bw。     

98%呋虫胺原药对大鼠两代繁殖毒性研究

为探讨98%呋虫胺原药对大鼠亲代生殖与子代早期发育的影响,采用饲喂法进行亲代(F0)和子一代(F1)染毒,剂量分别为0、8、40和200 mg/(kg·d),连续饲喂8周,观察亲代和子代大鼠的毒性表现,对生殖器官进行病理检查,计算繁殖指数和脏器系数。结果表明,与阴性对照组相比,F1代高剂量组雌性大鼠第2～7周的摄食量及总摄食量降低(P0.01;P0.05);高剂量组仔鼠出生存活率偏低(P0.05)。供试药剂对两代大鼠的最大无作用剂量为40 mg/(kg·d),最小有害作用剂量为200 mg/(kg·d)。     

吉祥草亚慢性毒性试验

依照国标化学品毒性鉴定和农药登记毒理学试验的相关规则,试验评价了吉祥草(RC)75 μm原粉亚慢性经口毒性.试验结果表明:RC原粉剂量达到100 mg/(kg·d)时,对大鼠的CHO、GLU、ALP和脾脏系数等观测指标产生明显影响,且有良好剂量-反应关系;当剂量达到1000 mg/(kg·d)时,对大鼠的BUN、肺和肾脏系数产生明显影响.RC 75 μm原粉对大鼠亚慢性经口毒性试验的最大无作用剂量为10 mg/(kg·d).     

9种杀虫剂对马铃薯桃蚜的室内毒力测定

为了筛选防治马铃薯上桃蚜的更好药剂,在室内采用叶片浸渍法,测定了9种杀虫剂对马铃薯桃蚜的毒力。结果表明:9种杀虫剂对马铃薯桃蚜都有较好的毒力,其中3.15%阿维·吡虫啉EC对马铃薯桃蚜的毒力最高,LC50值为0.730 4 mg/L;其次是5%高效氯氟氰菊酯ME、33%氯氟·吡虫啉SC、3.2%阿维菌素EC和9%噻虫·高氯氟SC,LC50值分别为0.873 1 mg/L、1.384 9 mg/L、1.855 3 mg/L和2.660 7 mg/L;22%氟啶虫胺腈SC、30%噻虫嗪SC和20%噻虫胺SC的LC50值分别为5.782 8 mg/L、5.8653 mg/L和6.279 3 mg/L;20%吡虫啉SL对马铃薯桃蚜的毒力最低,LC50值为22.895 2 mg/L。     

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.     

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.     

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。