小粒径玻璃微珠共混改性LLDPE的研究

研究小粒径玻璃微珠的粒径和用量时线形低密度聚乙烯(LLDPE)性能的影响。结果表明,添加不同粒径的玻璃微珠可使LLDPE的力学性能显著提高,耐热性能也有一定改善,粒径为3μm的玻璃微珠改性效果最好。随着玻璃微珠用量的增加,LLDPE的拉伸强度和冲击强度提高,但拉伸弹性模量和断裂伸长率基本不变。玻璃微珠粒径时LLDPE性能的影响大于用量的影响。     

空心玻璃微珠增韧高密度聚乙烯的性能研究

采用玻璃微珠（GB）对高密度聚乙烯（HDPE）进行增韧改性。通过扫描电子显微镜、偏光显微镜和力学性能测试考察了偶联剂处理、基体韧性、玻璃微珠粒子用量、粒径大小和结晶等因素对HDPE/GB体系微观形态和性能的影响。结果表明,偶联剂可以明显改善空心玻璃微珠在基体中的分散,对于HDPE/GB体系,要求基体的最低冲击强度为5.0～5.5KJ/m2。玻璃微珠用量25%,粒径2.5μm时,冲击强度可达38.0kJ/m2。     

玻璃微珠改性含油铸型尼龙力学性能研究

研究了玻璃微珠改性含油铸型尼龙复合材料的力学性能。结果表明,玻璃微珠使复合材料的冲击强度有所降低;拉伸强度、拉伸弹性模量、弯曲强度和弯曲弹性模量均得到提高,在玻璃微珠的质量分数为15％—20％时提高幅度较大;复合材料的硬度也有所提高。     

BMI树脂基轻质耐压复合材料的制备及性能研究

采用空心玻璃微珠填充改性双马来酰亚胺(BMI)树脂,研究了玻璃微珠用量和粒径以及表面处理的玻璃微珠,对材料压缩性能以及吸水性的影响。结果表明小粒径(10μm)较大粒径(70μm)玻璃微珠填充改性双马来酰亚胺树脂的压缩强度降低缓慢,经表面处理后可获得最佳效果。少量地加入玻璃微珠可降低环氧树脂的吸水性,但随着玻璃微珠含量的增大,体系的吸水性会随之增加。当玻璃微珠含量为30%时,复合材料密度降至0.74gcm3,压缩强度仍可以达到68.5MPa。     

玻璃微珠填充PP复合材料力学性能与熔融结晶的研究

研究了玻璃微珠填充聚丙烯(PP)中玻璃微珠含量及粒径大小对复合材料力学性能和熔融、结晶行为的影响。结果表明:填充体系随着玻璃微珠含量增加,拉伸强度增加,冲击强度降低。在相同条件下,小粒径微珠填充体系拉伸强度和冲击强度均高于大粒径微珠填充体系。玻璃微珠在PP中具有成核作用,PP以异相成核方式结晶,提高了PP的结晶温度,结晶速率增大,流动性先增加后降低。     

空心玻璃微珠填充改性双马来酰胺树脂复合材料耐热性能的研究

采用空心玻璃微珠填充改性双马来酰胺树脂（BMI），研究了玻璃微珠用量，粒径及表面处理对材料性能的影响，并用热机械分析仪（TMA）测定了材料的线膨胀系数。结果表明随着玻璃微珠质量份数的增加马丁耐热温度提高，线膨胀系数呈降低的趋势，小粒径（10μm）和经过表面处理的玻璃微珠对马丁耐热温度改性的效果更加显著。     

空心玻璃微珠填充改性双马来酰胺树脂复合材料耐热性能的研究

采用空心玻璃微珠填充改性双马来酰胺树脂（BMI），研究了玻璃微珠用量，粒径及表面处理对材料性能的影响，并用热机械分析仪（TMA）测定了材料的线膨胀系数。结果表明随着玻璃微珠质量份数的增加马丁耐热温度提高，线膨胀系数呈降低的趋势，小粒径（10μm）和经过表面处理的玻璃微珠对马丁耐热温度改性的效果更加显著。     

GB/HDPE复合材料拉伸性能及介电性能研究

采用小粒径玻璃微珠（GB）与HDPE熔融共混，研究了玻璃微珠用量及表面处理对复合材料拉伸性能及介电性能的影响。研究结果表明，无论玻璃微珠表面处理与否，GB／HDPE复合材料的拉伸强度和拉伸弹性模量均随着玻璃微珠用量的增加而增大；经过偶联剂KH550和EB151处理的玻璃微珠与HDPE复合后，拉伸强度和拉伸弹性模量有一定的提高。复合材料的介电常数随玻璃微珠用量增加呈现增大的趋势，经过改性的复合材料的介电常数比未经改性的有所增加，而玻璃微珠的添加和界面改性对介电损耗的影响不大。     

玻璃微珠填充PP复合材料力学性能与熔融结晶的研究

研究了玻璃微珠填充PP中玻璃微珠含量及粒径大小对复合材料力学性能和熔融、结晶行为的影响.结果表明,复合材料随着玻璃微珠含量增加,拉伸强度增大,冲击强度减小.在相同条件下,小粒径微珠填充体系拉伸强度和冲击强度均高于大粒径微珠填充体系.玻璃微珠在PP中具有成核作用,PP以异相成核方式结晶,提高了PP的结晶温度,结晶速率增大.流动性随着玻璃微珠含量的增加而增大,然后随之下降.     

HGB表面改性及粒径分布对ABS/HGB性能影响

研究空心玻璃微珠(HGB)的表面改性和粒径分布对丙烯腈-丁二烯-苯乙烯共聚物(ABS)/HGB复合材料力学性能的影响.结果表明:HGB的表面改性可以提高ABS/HGB复合材料的拉伸、弯曲和冲击强度;硅烷偶联剂KH550的改性效果优于KH560的;粒径分布窄的HGB填充ABS复合材料具有较高的拉伸、弯曲和冲击强度.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.