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1.
列举了含有毒有害物质的电镀工艺,介绍了可以替代的绿色电镀新工艺和重金属减排工艺,重点介绍了无氰高密度碱铜工艺在卫浴锌合金压铸件电镀中取代传统氰化预镀铜和焦磷酸盐镀铜工艺的应用状况。目前,该工艺已在锌合金门窗配件生产厂家和卫浴厂家中中试成功,门窗及卫浴锌合金压铸件预镀无氰碱铜后镀光亮酸铜,多层镍和铬的各项质量指标达到要求,实现了节水和含铜废水减排的目的。  相似文献   

2.
对酸铜预镀暗镍的代替工艺,浸镀铜无工业应用价值。开发了一种706型并配套专用电源的无氰碱铜预镀工艺,具有良好的结合力及大生产可操作性。镀锡青铜代镍尚无实用的无氰工艺。电镀光亮镍铁合金可节镍,是否省钱,应作认真评估。纳米镀镍在大生产中受到应用限制。介绍了一些镀薄镍后的封闭办法并提出了应用注意事项。镀锌或锌合金作底层镀装饰铬的工艺,有待进一步研究、完善。  相似文献   

3.
代镍节镍工艺评述   总被引:1,自引:0,他引:1  
随着镍价格的上涨,各种代镍节镍工艺应运而生。对生产中使用的各种代镍、节镍工艺包括钢铁件浸镀铜,无氰碱铜,电镀铜锡合金、镍铁合金,纳米镀镍,薄层亮镍和用锌或锌合金打底镀装饰铬等进行了评述。介绍了一些镀薄镍后封闭的方法。  相似文献   

4.
杨华祥 《电镀与精饰》2012,34(10):27-28
为了保护环境、消除污染,实现以无氰镀铜工艺代替氰化镀铜工艺,经实验研究,采用羟基乙叉二膦酸电解液镀铜工艺应用在铝合金零件表面镀铜/镍/铬工艺路线中预镀铜工序。经过生产实践证明,羟基乙叉二膦酸镀铜电解液深镀能力和均镀能力优良;镀液维护简单;镀层与铝合金基体结合力良好,产品合格率达99%以上。  相似文献   

5.
介绍了一种铝合金件环保镀银工艺,其工艺流程主要包括无氰沉锌、预镀无氰碱铜、焦磷酸盐加厚镀铜、无氰镀银和防变色处理。给出了各主要工序的溶液配方及工艺条件,测试了镀银液的深镀能力和均镀能力,以及镀层的结合力和抗硫化性能。该工艺的生产过程无氰、无镍,符合清洁生产要求。  相似文献   

6.
简讯     
上海沪光电镀研究所最近在春城昆明市召开了“柠檬酸光亮镀铜”工艺推广交流会。该工艺无氰无毒,同时对钢铁基体可省去预镀而直接镀铜,沉积速度为20~30μm/h,且光亮,深镀能力比氰铜还好,具有良好的推广使用前景。  相似文献   

7.
分析了基于硫酸盐光亮酸性镀铜体系的钢铁件浸镀铜工艺工业化应用的不可行性,以及浸镀与电沉积相结合的酸性镀铜工艺的特点.介绍了酸铜光亮剂、钢铁件活化原理、无氰碱铜配位荆等研究的最新进展.指出HEDP无氰碱铜镀液具有化学活化作用,以及预浸能提高镀层结合力.  相似文献   

8.
无氰镀铜的实验研究与生产应用进展(一)   总被引:1,自引:1,他引:0  
分析了基于硫酸盐光亮酸性镀铜体系的钢铁件浸镀铜工艺工业化应用的不可行性,以及浸镀与电沉积相结合的酸性镀铜工艺的特点.介绍了酸铜光亮剂、钢铁件活化原理、无氰碱铜配位荆等研究的最新进展.指出HEDP无氰碱铜镀液具有化学活化作用,以及预浸能提高镀层结合力.  相似文献   

9.
概述本发明展示了一种新型的碱性无氰铜锌合金电镀液及其电镀工艺;能镀出各种铜锌比例的合金镀层;这种镀液能直接在工业上通常使用的铜、铁、钢及锌合金上电镀,而不需要预先氰化镀铜或冲击镀镍来保证镀层的结合力;这种镀液所镀出来的镀层没有象氰化镀液可能产生的那种蚀点区;镀液中金属离子可采用一种简单而有效的方法除去;废水不需要象氰化  相似文献   

10.
将锌-铁合金电镀工艺应用于锌压铸件电镀,分析了锌压铸件镀前处理特点及注意事项,比较了锌压铸件氰化镀铜和锌-铁合金电镀作预镀层的优劣,锌-铁合金电镀工艺能取代氰化镀铜作锌压铸件预镀工艺,并可在锌-铁合金镀层上镀防金、铬等装饰性镀层。  相似文献   

11.
12.
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.  相似文献   

13.
14.
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.  相似文献   

15.
16.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
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。  相似文献   

17.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

18.
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   

19.
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   

20.
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   

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