共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
锌铁合金电镀工艺研究 总被引:2,自引:0,他引:2
研究了碱性锌酸盐锌铁合金电镀工艺,探讨了各工艺条件对镀层铁含量的影响.通过控制工艺条件,获得了含铁量为9%~12%的光亮锌铁合金镀层.最佳工艺条件为:znO 8~10 g/L,NaOH 110~130 g/L,三乙醇胺20~30 mL/L,FeSO4·7H2O3.3~4.5 g/L,添加剂30~60mL/L,阴极电流密度1~2A/dm2,搅拌速率160~240r/min,温度28~35℃.电化学极化测试和中性盐雾腐蚀试验的结果表明,采用此工艺所得锌铁合金镀层的耐蚀性明显优于纯锌镀层. 相似文献
3.
锡铋合金电镀工艺条件的研究 总被引:3,自引:0,他引:3
锡铋合金镀层因具有无晶须、熔点较低、可焊性好等优点,在国外已大量推广应用,在国内的研究和应用则较少。本文通过条件实验和正交试验对硫酸盐锡铋合金电镀液配方进行了改进。研究了镀液中稳定剂、平滑剂、光亮剂、表面活性剂含量及操作条件对镀液及镀层性能的影响。结果表明,该镀液稳定、易操作,且获得的Sn-Bi合金镀层均匀致密、光亮、结合力及钎焊性优良。得到合适的工艺条件为:镀液中稳定剂含量1.5~2ml/L、平滑剂含量0.5~1g/L、光亮剂含量8~10ml/L、表面活性剂含量3g/L、pH值0.9~1.1、阴极电流密度1A/dm^2。 相似文献
4.
5.
本文研究了以Na_6[Au(SO_3)_2HY]为主盐的亚硫酸盐—EDTA无氰镀金工艺。介绍了镀液的配制方法。试验了十九种添加剂通过大量的筛选工作,选出了用镍盐为光亮剂。用正交试验法与单因素试验法研究了主盐浓度、光亮剂浓度、阴极电流密度,温度等因素的影响。确定工艺条件为主盐Na_6[Au(SO_3)_2HY]5~6g/L,光亮剂NiSO_40.01g/L,阴极电流密度D_K0.2~0.3A/dm~2,pH=9.5,用磷酸盐作缓冲剂。试验表明,氯离子对镀液稳定性虽无显著影响,但可影响镀层质量,故应尽量除去。此外还做了极化曲线和微分电容的测试。笔者认为在实验室内用本法代替真空蒸镀有很大的优越性。 相似文献
6.
以黄铜为基材,研究了吡啶添加剂-氨盐体系的电镀钯工艺,分析了钯盐、氯化铵、吡啶添加剂质量浓度,温度及pH对镀液和镀层质量的影响.在Pd(NH3)2Cl220 g/L,NH4Cl 15 g/L,NH3·H2O 35 mL/L,吡啶添加剂25 g/L,pH 7~8,温度25~35℃和电流密度0.4~0.5 A/dm2的条件下,获得了厚度达35 μm的光亮钯镀层.该镀层与基体结合力良好,能满足光电经纬仪的工作要求. 相似文献
7.
本文研究了一个氨基磺酸盐电镀液,可以用来在铜板表面,电沉积出Pb/Sn为90/10到40/60组成的铅锡二元合金。在25℃,pH值1.2的镀液中,通常可采用0.5 A/dm~2的电流密度。本文研究了一系列的镀液添加剂,发现采用1.5g/L胨+1.5g/L明胶+1.5g/L联苯三酚可获得最好的镀层质量。 相似文献
8.
以柠檬酸盐、酒石酸盐为主配位剂,研究了锌基合金上碱性无氰镀铜工艺.镀液组成和工艺条件为:二水合氯化铜16g/L,柠檬酸钾82g/L,酒石酸钾钠20g/L,胺化合物29g/L,硼酸30g/L,氯化钾28g/L,氢氧化钾20g/L,光亮剂0.01 mL/L,温度45 ℃,pH为9(用KOH或盐酸调节),镀液搅拌,电流密度1.0A/dm2.研究了搅拌,镀液温度、pH、铜离子质量浓度和添加剂对镀层外观的影响.测试了镀液的电流效率,深镀能力,分散能力,抗杂质能力,与基体的结合力,表面形貌和结构.结果表明,添加剂体积分数在0.01~1.50 mL/L范围内均可获得光亮的镀层;电流效率随电流密度,温度和pH的提高而增大;镀液有较强的抗杂质能力,深镀能力达100%,分散能力为84.1%,电流效率在90%左右.镀层晶粒细小、致密、平整,颗粒分布均匀,与基体结合牢固. 相似文献
9.
10.
11.
12.
M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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. 相似文献
13.
14.
Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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. 相似文献
15.
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. 相似文献
16.
17.
18.
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. 相似文献
19.
中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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. 相似文献
20.
中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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。 相似文献