低温快速化学镀镍工艺的研究

在弱酸性化学镀镍溶液中加入一种添加剂,在30～95 °C范围内都可获得镍磷合金镀层,沉积速率最高可达30 μm/h,同时测试了温度、pH值及镀液成份对沉积速率的影响,并讨论了镀液的稳定性及添加剂的作用.     

氨基磺酸盐镀镍的沉积速率与电流效率的研究

采用测厚法和恒电流沉积法,分别研究了镀液温度、阴极电流密度和添加剂对氨基磺酸盐镀镍的沉积速率与电流效率的影响。结果显示:在镀液中不含任何添加剂的前提下,镀镍的沉积速率和电流效率均随镀液温度的升高及阴极电流密度的增大明显提高,最高分别达到0.027 3μm/s和73.4%;而在电镀工艺参数相同的条件下,向镀液中加入适量的添加剂,镀镍的沉积速率和电流效率均略有提高。     

中温化学镀镍工艺及添加剂的研究

鉴于目前化学镀镍工艺存在的镀液温度高、能耗大及稳定性差等缺点,提出了一种中温化学镀镍工艺。在正交试验结果的基础上,采用三种汪厍剂组合使用,分别研究了络合剂、组合添加剂、温度及ＰＨ值对镀层沉积速度的影响。结果表明：采用组合添加剂能明显提高镀液的稳定性及沉积速度。     

电镀镍中间体对酸性化学镀镍的影响研究

在由26.8g/L NiSO_4.6H_2O、150 mL/L BH-320B和30mg/L稳定剂组成的酸性化学镀镍液中,研究了电镀镍用中间体ATQM、SSO3、MPA和DEP对沉积速率、镀层性能和镀液稳定性的影响。结果表明,ATQM和SSO3可作为化学镀镍液的促进剂,MPA和DEP可用作化学镀镍液的光亮剂。此外,MPA和SSO3还对化学镀镍液起辅助稳定剂的作用。镀液中不同添加剂的存在对镀层结构无明显影响,所得镀层均为非晶态结构。     

几种品牌硫酸镍的化学镀镍性能对比性研究

通过偏转法、划痕仪法和中性盐雾试验等方法,测试分析了国内外市场上六种主要品牌硫酸镍的中磷化学镀镍层的内应力、结合力及耐蚀性和高磷化学镀镍层的耐蚀性、结合力及镀液沉积速率等性能。测试结果显示,金柯品牌硫酸镍所获取的中磷化学镍层内应力、结合力和耐蚀性明显优于其它品牌,高磷化学镀镍层耐蚀性、结合力及镀液的沉积速率也优于其它品牌,该品牌硫酸镍更适合于磁盘高磷化学镀镍。     

镁合金化学镀镍工艺的研究

采用硫酸镍为主盐、次磷酸钠为还原剂,并在镀液中加入氟化物和稳定剂,研究了镁合金的化学镀镍工艺.运用正交试验分析了镀液中各主要组分对镀速及耐蚀性等影响,优选化学镀最佳工艺.该工艺沉积速率快,镀层耐蚀性优异.运用X-射线衍射方法对镀层的组织结构进行了分析,结果表明,镁合金化学镀镍层由非晶态的镍及部分微晶的镍组成.     

钙离子对化学镀镍溶液性能的影响

研究了钙离子对化学镀镍镀液的影响,测试了10、30和150mg/L的钙离子对镀液的寿命、稳定性及沉积速率的影响。结果表明,随着镀液中钙离子质量浓度的升高,镀液稳定性下降,使用寿命减短;同时还测试了钙离子对镀层结合力、耐蚀性、耐磨性及镀层显微形貌的影响。结果显示,随着钙离子质量浓度的升高,镀层耐蚀性及光亮性变差,结合力降低。钙离子对化学镀镍具有较大的影响,故在实际生产过程中应严格控制化学镀镍溶液中钙离子的质量浓度。     

铝合金化学镀镍-磷合金的研究

铝合金的预处理是化学镀镍最为重要的一个环节。采用二次浸锌法对铝合金表面进行预处理。考察了浸锌过程中浸锌时间、浸锌温度、退锌时间等因素对沉积速率的影响。化学镀镍采用先碱镀再酸镀的方式,获得均匀、光亮的镀层,并讨论了主盐、还原剂、配位剂、pH值等因素对酸性化学镀镍沉积速率的影响,得到了最佳的工艺条件和镀液配方。制得的Ni-P合金镀层表面均匀、致密。     

延长化学镀镍溶液寿命的研究

探讨了用间隔取液法延长化学镀镍液使用寿命.通过分析p(亚磷酸钠)和沉积速率随每周期取出部分溶液的关系得出结论,当取液量大于化学镀镍溶液15％时,化学镀镍溶液中的有害离子均不超过其临界质量浓度,化学镀镍溶液可以连续工作并能维持较高的镀速.     

粉体化学镀镍液复合稳定剂的研究

文章分别考察了硫脲、碘化钾、乙酸铅和硫酸铜等四种稳定剂对粉体化学镀镍液稳定性和沉积速率的影响。实验结果表明:稳定剂的加入都可以改善镀液的稳定性,而对于镀液沉积速率而言,其加入量不是愈大越好,存在一个最佳的浓度范围。试验通过正交试验优选出既能使镀液稳定性良好,又有一定的沉积速率的复合稳定剂组成。试验结果显示,添加了复合稳定剂的化学镀液稳定时间达到3072 s,沉积速率为25.69μm/h。     

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。