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1.
The spectrophotometric characteristic of a new reagent 1, 4, 9, 12-tetraaza Cyclo-2, 3, 6, 7, 10, 11 , 14, 15- tetrabenzocetanan-5, 8, 13, 16-tetraone (TCTCT) and its complex with Cu(Ⅱ) were studied. The reagent and its complex with Cu(Ⅱ) have a similar maximum absorbance at 446 nm. In C6H4(C2O4HK)-NaOH buffer (pH=4.00), the complex of Cu(Ⅱ)-TCTCT formed when it was heated. The absorbance increased with the increase of the concentration of Cu(Ⅱ) in the range of 1.6×10-7-5.5×10-5mol/L. The composition ratio of the complex was formed to be 1:1 using the molar ratio method. The method was simple, rapid and sensitive, giving an apparent molar absorptivity of 1.25×105L.mol-1.cm-1and the apparent stability constant of 1.04×106. The method was directly applied of copper in fresh milk.  相似文献   

2.
This article examines a family of ion-exchange fibers, FIBAN, containing primary and secondary amine groups. These ion exchangers have a fiber diameter of 20–40 Μm, high osmotic and mechanic stability, a high rate of adsorption and regeneration, and excellent dynamic characteristics as filtering media. Inparticular, this article discusses the use of FIBAN fibrous ion exchangers in the recovery of gold cyanide andbase-metal cyanides (copper and mercury) from mineral-leaching solutions. The influence of polymer structure and water content on their extraction ability is described, along with key parameters of gold hydrometallurgy such as extraction efficiency, selectivity, pH dependence, gold cyanide loading, kinetics, and stripping.  相似文献   

3.
This work presents a self-healing protective coating for copper. The complex coating is composed of copper(II) 8-hydroxyquinolinate (Cu(8HQ)2) 3D network film storing corrosion inhibitor as base layer and epoxy as top layer covering on the base layer. The results of EIS and polarization curves reveal the self-healing effect of Cu(8HQ)2 3D network film with corrosion inhibitor embedded. After being scratched with a knife-edge, the complex coating rapidly releases inhibitor embedded in 3D network structure to suppress the corrosion process. The scratch on the coating is covered with inhibitor adsorption film and the anodic activity is restrained.  相似文献   

4.
The electrochemical behaviors of various copper salts complexes coordinated with equal molar ethanolamine were studied, and those of Cu(p-OTs)2 and Cu(p-OTs)2/ethanolamine(1:1) complex in CH3OH or DMF were characterized. The results show that the reduction of Cu(Ⅱ) in Cu(p-OTs)2 is via one two-electron step mechanism both in CH3 OH and DMF. The reduction mechanism transforms to two one-electron steps in the case of Cu (p-OTs)2/ethanolamine(1:1) in DMF. However, it does not change in CH3OH. All the Cu(Ⅱ)/ethanolamine(1:1) with the electrochemical reactions are through two one-electron steps, and can act as mimetic enzyme to oxidize 1, l‘-bi-2-naphthol. The Cu(Ⅱ)/ethanolamine(1:1) with electrochemical reactions through one two-electron step could not act as mimetic enzyme. It is concluded that the transformation between centre Cu(Ⅱ) and Cu(Ⅰ) is the crucial condition for the catalytic activity of copper-amine complex.  相似文献   

5.
1 INTRODUCTIONOxidation ,reduction ,andadsorptionusuallyaregoodmethodstoremoveorganiccompoundsinwater ,andthecombinationofthesemeth  相似文献   

6.
为研制一种轻质毫米波干扰材料,试验以化学镀的方式对竹纤维进行表面金属化改性(镀覆的金属为铜和镍);并检测了金属化竹纤维的8mm波衰减性能.测试结果显示金属化竹纤维的8mm波衰减性能较好:20mg镀铜竹纤维可衰减17.5dB,30mg镀镍竹纤维可衰减24.2dB.化学镀工艺对金属化竹纤维的衰减性能有一定影响,在相同工艺下所制备试样的8mm波衰减分贝值随测试用量的增加而增加.试验结果表明金属化竹纤维可望成为一种新型毫米波干扰材料.  相似文献   

7.
为了破坏冶炼废水中重金属有机螯合物,例如Cu-EDTA配离子废水,研究一种破络并预处理的新方法。该方法基于铁碳微电解反应原理,.OH在酸性有氧气存在的条件下产生,并在铁碳表面攻击吸附的有机基团导致螯合物的破坏,从而使铜离子将从有机物中剥离下来,然而EDTA将被.OH降解。研究pH值、温度、微电解反应时间、Fe/C质量比对铜离子脱除率及总有机碳(TOC)残余含量的影响,通过扫描电子显微镜分析(SEM)、能谱分析(EDS)、红外光谱分析(FTIR)研究处理前、后样品的表面官能团变化及形貌推断铁碳微电解反应的机理。并进行工业条件优化,得到最佳工艺条件:pH值为2,温度为常温,Fe/C质量比≥0.02,时间为60min,有氧气存在。在该条件下TOC浓度为200mg/L、铜离子浓度为60mg/L的废水反应完成后TOC和Cu残余浓度分别减低到40.66和1.718mg/L;羟基自由基降解反应机理合理解释了该实验现象。  相似文献   

8.
测定了新型抗肿瘤洛铂衍生物cis-[trans-1,2-双(氨甲基)环丁烷·3-氧代-1,1-环丁烷二羧酸合铂(Ⅱ)](LLC-1903)在D_2O和DMSO-d_6中的~1H NMR,并进行比较、分析和归属。对2种溶剂中的~1H NMR谱图差异进行了解释,提出在水溶液中由于氢键的形成,导致在环丁烷上的2组CH_2处于不同的空间位置,氢谱出现明显的分裂。  相似文献   

9.
The tertiary amine can be used to extract Fe(Ⅲ) very effectively in the pH range resulting inpartial hydrolysis of Fe~(3+) ions.The iron extracted into the organic phase can be strippedrather easily with dilute H_2SO_4 or even with H_2O.Fe(Ⅲ) is extracted into the tertiary aminesulfate solution in the form of[(R_3NH)_2Fe(OH)(SO_4)_2]_2 complex by adduct formation.Equa-tion was derived to represent the chemical reactions involved during extraction.From theinfrared spectrum studies on the extraction species in waxy solid form separated from the so-lution,sulfate group is a bidentate ligand to the iron atom.The extraction species has beenconsidered to contain (FeOH)_2 unit based on the ultra violet spectra.The possible structure ofthe extraction species has been proposed.  相似文献   

10.
A series of mixed mode tests were carried out on 18-8 stainless steel in boiling42% MgCl_2 solution.The results show that for any K_Ⅱ/K_Ⅰ ratio,the SCC direction coin-cides well with the crack tip maximum normal stress plane,while the SCC resistance of thematerial reduces as the ratio of K_Ⅱ/K_Ⅰ increases.The experimental results were discussed inthe light of anode dissolving mechanism and the effect of mixed mode loading on crack tipstress and strain.It is concluded that for fracture analysis if mixed mode cracks were simplytaken into account as mode Ⅰ cracks,and only mode Ⅰ testing results as mode Ⅰ fracture criter-ion were employed,it may not be safe.  相似文献   

11.
采用前驱体分解法制备了高纯ZrWMoO8粉体。为获得ZrWMoO8/Cu复合材料,首先将ZrWMoO8与Cu按1:1的比例进行研磨获得混合粉,采用化学镀的方法获得ZrWMoO8与Cu比例为1:1的包覆粉,然后压片并在氩气气氛保护下于500℃烧结3 h获得复合材料。详细研究了复合材料的热膨胀性能并且发现包覆粉更适合制备ZrWMoO8/Cu复合材料。结果表明:烧结后,混粉制备的复合材料中部分ZrWMoO8发生了分解并且与Cu发生了反应,而以包覆粉制备的ZrWMoO8/Cu复合材料未检测出ZrWMoO8的分解产物。包覆粉制备的复合材料在25~250℃显示的热膨胀系数为3.3774×10-6℃-1,其相对密度达到90.6%。  相似文献   

12.
采用水冷铜模吸铸法制备直径2mm的(Cu50Zr50)92Al8块体非晶合金。利用X射线衍射(XRD)、差示扫描量热分析仪(DSC)对该非晶合金的结构及热力学参数进行表征。利用万能试验机在过冷液相区内对该非晶合金进行压缩变形,研究变形量(20%,60%和80%)对非晶合金显微结构和热稳定性的影响。结果表明,塑性变形使得该非晶合金的热稳定性降低,并导致其部分晶化,其晶化程度取决于合金的变形量的大小,当变形量为80%时,该合金的XRD图谱中出现了明显的晶化峰。晶化相的析出使得变形后的非晶合金的显微硬度有明显提高。  相似文献   

13.
以铜焊丝为填充材料对TA15钛合金与18-8不锈钢进行填丝钨极氩弧焊(TIG).利用金相显微镜(OM)、扫描电镜(SEM)、电子探针(EPMA)及显微硬度计对TA15/18-8接头的微观组织、相组成、元素分布及显微硬度进行了分析.结果表明,焊缝组织为铜固溶体枝晶;TA15钛合金侧熔化未混合区为α-Ti与磷化物脆性相Ti3P,Ti(Cu,Fe)的混合组织;18-8不锈钢侧熔合区为Fe-P共晶组织;磷在18-8不锈钢侧熔合区的聚集促进了共晶组织的形成,未参与共晶反应的铜形成团状聚集区;两侧熔合区显微硬度明显高于热影响区和焊缝,Ti3P脆性相导致钛合金侧熔化未混合区的显微硬度最高值达720 HV0.5.  相似文献   

14.
含杂原子的双子表面活性剂的合成与应用   总被引:2,自引:0,他引:2  
以N,N-二甲基十二烷基胺和3-氧杂-1,5-二溴戊烷为原料合成了以3-氧杂戊基为联接基团的季铵盐型双子表面活性剂。产物的结构用红外光谱和核磁共振氢谱进行表征。测定了25℃下双季铵盐水溶液及其与NP-6、NP-8、NP-15、AEO-3的二元复配体系的表面张力。结果表明,与传统单链表面活性剂相比,双季铵盐表面活性剂具有更为优异的表面活性;每一种二元复配体系都具有显著降低表面张力的协同增效作用。与传统杀菌剂1631(十六烷基三甲基溴化铵)相比,双季铵盐表面活性剂具有更为优异的杀菌抑菌性能,其中对苹果轮纹菌、小麦赤霉菌的杀菌抑菌作用最佳。考察了弱碱性介质中双季铵盐水溶液及其复配体系对锌的缓蚀作用,结果表明:当pH值为8,双季铵盐水溶液的浓度低于20 mg/L时对锌具有较好的缓蚀作用,而高于此浓度时的缓蚀效果明显下降并表现出一定的腐蚀作用;在复配体系中,双季铵盐与NP-15的1∶1二元复配体系对锌的缓蚀作用最好。  相似文献   

15.
MBO缓蚀膜中Cu的价态及成膜机制   总被引:7,自引:1,他引:6  
用光电子能谱(XPS)、红外光谱(IR)和扫描隧道显 微镜(STM),对Cu在含NaCl的2-琉基苯并唑(MBO)溶液中处理后,其表面所形成的缓蚀膜进 行了研究.缓蚀膜的Cu2p\-\{3/2\}结合能值为932.3 eV,在Cu2p\-\{3/2\}和Cu2p\-\{1/2 \}之间没有“卫星峰”存在,且俄歇峰CuLMM的结合能为337.6 eV,表现了典型的一价Cu化 合物的特征.该缓蚀膜的红外光谱与MBO的一价Cu的合成化合物的红外谱图相一致.在形成缓 蚀膜前后,N1s和S2p的结合能变化显著,表明MBO分子可能通过S和N原于与一价铜离子键合 的.原位的STM表明,Cl\+-的存在可使MBO在Cu表面形成致密的三维膜.对MBO缓蚀膜的形成机 理进行了分析,解释了在MBO缓蚀膜形成过程中Cu腐蚀电位的变化.  相似文献   

16.
目的研究E16和E44两种水性环氧防水涂层材料对混凝土试块吸水性能的影响,以比较两种防水材料的性能。方法分别对两种防水涂层材料设计不同的涂层配合比和涂层厚度,进行混凝土毛细吸水实验,对比混凝土试块在喷涂防水涂层材料前后的毛细吸水系数变化,以此评价防水涂层材料对混凝土试块吸水性能的影响。结果涂层混凝土试块的吸水系数随涂层厚度的增加而减小。在一定范围内,涂层混凝土试块的吸水系数随n(胺氢)/n(环氧基)的增大而先减小,后增大。兼顾性能与成本,确定E16和E44两种防水涂层材料的配合比分别为n(E16)∶n(Anquamine721)=1∶1,n(E44)∶n(Anquamine 721)=1∶0.9,涂层喷涂厚度皆为(300±20)μm。此时,E16和E44两种涂层混凝土试块的吸水系数分别为各自对应空白混凝土试块的3.5%和3.4%。结论相比之下,E44防水涂层材料对混凝土试块吸水性能的影响较大。  相似文献   

17.
The failure behavior for two kinds of phenolic-epoxy/tetraglycidyl metaxylediamine composite coatings in 60 °C borax aqueous solution was evaluated using electrochemical methods (EIS) combined with scanning electron microscopy, confocal laser scanning microscope, water immersion test, and Raman spectrum. The main focus was on the effect of curing agent on the corrosion protection of coatings. Results revealed that the coating cured by phenolic modified aromatic amine possessed more compact cross-linked structure, better wet adhesion, lower water absorption (0.064 mg h?1 cm?2) and its impedance values was closed to 108 Ω cm2 after immersion for 576 h, while the coating cured by modified aromatic ring aliphatic amine was lower than 105 Ω cm2. The corrosion mechanism of the two coatings is discussed.  相似文献   

18.
The synthesis and crystal structure of an polyoxometalate-based organic-inorganic complex [Cu(DMF)3(H2O)2]2[SiMo12O40]·2H2O (DMF = N, N-dimethyl formamide) is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper(Ⅱ) centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.  相似文献   

19.
Abstract

Copper specimens have been exposed to the action of marine, marine industrial, urban and rural atmospheres of Saudi Arabia. Environmental factors such as average temperature, average relative humidity and deposition rates of atmospheric pollutants (i.e. Cl- and SO2) was investigated. By applying the standard ISO 9223, the aggressiveness of the atmospheres corresponding to the different test stations has been determined. Calculations of corrosion rates were made via loss of weight after one, two and three years of exposure and characterisation of the corrosion products formed on samples have been analysed using X-ray diffraction. Three main sequences have been identified on outdoor copper, representing different reaction routes in chloride dominated environments. Many kinds of patina were found on copper specimens such as cuprite (Cu2 O), atacamite (Cu2 Cl(OH)3), paratacamite (Cu2 (OH)3Cl), copper amine nitrite hydroxide, gerhardite, copper hydroxide nitrate and copper amine nitrate.  相似文献   

20.
Inhibition of copper corrosion in acidic chloride pickling (0.5 M HCl) solutions by 5-(3-Aminophenyl)-tetrazole (APT) as a corrosion inhibitor has been studied using potentiodynamic polarization, chronoamperometry (CA), electrochemical impedance spectroscopy (EIS), weight-loss and Raman spectroscopy investigations. Electrochemical measurements showed that the presence of APT and the increase of its concentration significantly decrease the cathodic, anodic, and corrosion currents as well as corrosion rates. This effect also decreases the dissolution currents of copper at 200 mV vs. Ag/AgCl, and greatly increases surface and polarization resistances and inhibition efficiency as indicated by CA and EIS measurements. Weight-loss data revealed that the corrosion rate of copper decreases to a minimum and the inhibition efficiency increases to a maximum in the presence of APT and upon increasing of its concentration even after 72 h of copper coupons immersion. Comparing the Raman spectrum obtained on the copper surface after its immersion in HCl solution containing 1.0 mM APT for 72 h to the spectrum obtained for the solid APT alone indicated that APT molecules inhibit the corrosion of copper via their adsorption onto its surface.  相似文献   

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