Identification of a minor component of the sex pheromone ofLeucoptera malifoliella (Lepidoptera,lyonetiidae)

A new minor component in the female volatile extract ofLeucoptera malifoliella (Costa) (Lepidoptera, Lyonetiidae) has been identified as 5,9-dimethyloctadecane (2). The amount detected of the minor compound2 ranged from 4 to 8% in comparison with the major component 5,9-dimethylheptadecane (1). Neither compound has been found in the male volatile extract. The identification has been based on its spectroscopic properties and Chromatographic behavior in comparison with an authentic synthetic sample. The synthesis has been carried out through a short route from 2,6-dimethylcyclohexanone (3). In field tests, compound2 appears to act as a Synergist of the major component1 when mixed with the latter in a 1000.1– 5 ratio.     

聚合物防老化稳定剂的协同作用机理

从聚合物热氧老化和光氧老化机理出发，介绍了不同稳定剂间的相互作用，可能产生的协同及反协同作用机理以及一些实用实例。     

Host Plant Volatiles Synergize Response to Sex Pheromone in Codling Moth, Cydia pomonella

Plant volatile compounds synergize attraction of codling moth males Cydia pomonella to sex pheromone (E,E)-8,10-dodecadien-1-ol (codlemone). Several apple volatiles, known to elicit a strong antennal response, were tested in a wind tunnel. Two-component blends of 1 pg/min codlemone and 100 pg/min of either racemic linalool, (E)-beta-farnesene, or (Z)-3-hexen-1-ol attracted significantly more males to the source than codlemone alone (60, 58, 56, and 37%, respectively). In comparison, a blend of codlemone and a known pheromone synergist, dodecanol, attracted 56% of the males tested. Blends of pheromone and plant volatiles in a 1:100 ratio attracted more males than 1:1 or 1:10,000 blends. Adding two or four of the most active plant compounds to codlemone did not enhance attraction over blends of codlemone plus single-plant compounds. Of the test compounds, only farnesol was attractive by itself; at a release rate of 10,000 pg/min, 16% of the males arrived at the source. However, attraction to a 1:10,000 blend of codlemone and farnesol (42%) was not significantly different from attraction to codlemone alone (37%). In contrast, a codlemone mimic, (E)-10-dodecadien-1-ol, which attracted 2% males by itself, had a strong antagonistic effect when blended in a 1:10,000 ratio with codlemone.     

Allelopathic Potential and Chemical Constituents of Volatile Oil from Ageratum conyzoides

Fresh leaves and volatile oil of the important weed Ageratum conyzoides in south China were highly inhibitory to seedling growth of various cultivated crops, especially in an adverse habitat. The constituents of the volatile oil were analyzed by GC-MS. Eleven components were identified and six main components, precocene I, precocene II, 3,3-dimethyl-5-tert-butylindone, -caryophyllene, -bisabolene, and fenchyl acetate, were isolated by means of column chromatography. Precocene I, precocene II, -caryophyllene, and 3,3-dimethyl-5-tert-butylindone inhibited seedling growth of acceptor plants. Inhibitory activity of the volatile oil was more intense than that of the pure components. Fenchyl acetate and -bisabolene have no inhibitory activity, but when mixed with precocene II, they increased the inhibitory activity to growth of acceptor seedling plants. Experiments show that allelopathic synergism exists among allelochemicals of Ageratum conyzoides.     

Interactions of pheromone component odor plumes of western pine beetle

The relationships between catch ofD. brevicomis LeC. at sources of the synergistic pheromone components,exo-brevicomin (E) and frontalin (F), and increasing distance of separation of sources were investigated in the forest. The two components were each released with the host monoterpene, myrcene (M), in trap pairs. The traps of each pair were spaced apart at various distances (0–16 m) in either horizontal or vertical lines that were perpendicular to the mean wind direction. Both sexes were most strongly attracted when the two components were released from the same source, and increasing distance of separation between components caused exponential decreases in trap catch for all trap configurations. Males were significantly more attracted to traps with E, M alone than to corresponding traps with F, M alone, while females exhibited a preference for F, M. The theoretical relationships and properties of two coalescing plumes of individual components and their intersecting active space are presented and discussed. It is proposed that confusion or communication disruption techniques for insect control may be more successful if components are released individually from many points rather than released similarly in blends. Dendroctonus brevicomis LeC. (Coleoptera: Scolytidae).Supported in part by grants from U.S.A. and Sweden, NSF (INT-8503520), STU (84-3937), NFR, FRN, and SJFR.     

超声波协同铁粉降解水中2,4-二氯酚的研究

采用超声波/铁粉协同降解水中2,4-二氯酚。考察了初始浓度、超声功率、铁粉投加量以及pH对降解效率的影响,并初步探讨了超声波/铁粉协同降解2,4-二氯酚的动力学规律。结果表明,超声波与铁粉对2,4-二氯酚的降解具有明显的协同效应。降解效率随超声功率和铁粉投加量的增大而增大,随初始浓度的增大而减小。pH对2,4-二氯酚的降解有显著影响,在pH为4时,降解效率最高。超声波/铁对2,4-二氯酚的协同降解符合一级反应动力学规律,降解速率常数为1.52×10-2min-1,与铁粉单独作用和超声单独作用相比,分别提高了约5倍和13倍。     

九种助剂对草甘膦的增效作用比较

草甘膦异丙胺盐药液中分别加入九种助剂后对空心莲子草喷多处理，测定植株鲜重及再生植株鲜重，并测定药液的表面张力。结果表明，药液中助剂UC—12、TI—800、JFC、Tween20的浓度达到1000—5000mg/L时鲜重抑制率比CK提高了6—20个百分点。加入UC—12、JFC对根茎抑制作用最为明显，复发率降低了约12个百分点。九种助剂降低药液表面张力的效能从高到低顺序为：农乳500＞904＞APG＞JFC＞TL800＞UC-12＞Tween20＞961＞SD。上述试验结果表明，助剂UC-12、TI—800、JFC、Tween20对草甘膦的增效作用较为显著，助剂增效作用大小与降低表面张力的效能无密切相关性。     

Synergistic Sex Pheromone Components of White-Spotted Tussock Moth, Orgyia thyellina

In 1996, the exotic white-spotted tussock moth (WSTM), Orgyia thyellina (Lepidoptera: Lymantriidae), was discovered in Auckland, New Zealand. Because establishment of WSTM would threaten New Zealand's orchard industry and international trade, eradication of WSTM with microbial insecticide was initiated. To monitor and complement eradication of WSTM by capture of male moths in pheromone-baited traps, pheromone components of female WSTM needed to be identified. Coupled gas chromatographic–electroantennographic detection analysis of pheromone gland extract revealed several compounds that elicited responses from male moth antennae. Mass spectra of the two most EAD-active compounds suggested, and comparative GC-MS of authentic standards confirmed, that they were (Z)-6-heneicosen-11-one (Z6–11-one) and (Z)-6-heneicosen-9-one, the latter termed here thyellinone. In field experiments in Japan, Z6–11-one plus thyellinone at a 100:5 ratio attracted WSTM males, whereas either ketone alone failed to attract a single male moth. Addition of further candidate pheromone components did not enhance attractiveness of the binary blend. Through the 1997–1998 summer, 45,000 commercial trap lures baited with 2000 g of Z6–11-one and 100 g of thyellinone were deployed in Auckland towards eradication of the residual WSTM population.Dedicated to my dear mother in honor of her 75th birthday     

低密度聚乙烯阻燃薄膜性能研究

以十溴二苯醚、三氧化二锑为阻燃剂,对包装用低密度聚乙烯薄膜制品的阻燃性能和力学性能进行了研究,并用氧指数测试仪和万能试验机评价其阻燃性能和力学性能。实验结果表明:在DBD-PO/Sb2O3/LDPE体系中,两种阻燃剂之间明显存在协同阻燃效应,极限氧指数大幅度提高;其力学性能也达到了相应的使用标准。     

Sex phermone components of mulberry looper,Hemerophila atrilineata butler (lepidoptera: Geometridae)

(6Z-9S, 10R)-Epoxy-octadecene (SR-1) and (3Z, 6Z-9S, 10R)-epoxy-octadecadiene (SR-2) are sex pheromone components of the mulberry looper (MBL),Hemerophila atrilineata Butler. Compounds extracted from female MBL pheromone glands were identified by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry. In field experiments in China,SR-2,RS-2, or both combined were hardly attractive, butSR-2 in combination withSR-1 attracted significant numbers of MBL males. Synergistic behavioral activity ofSR-1 plusSR-2, but not of corresponding antipode mixtures, indicates enantiospecificity of MBL pheromone communication. Because blends of racemic and enantiospecific (SR)1 plus2 were similarly attractive, racemic1 plus2 may have potential for mass trapping or confusion of MBL males in commercial mulberry plantations.