铝材无烟化学抛光剂的研制

为了消除传统的三酸抛光对环境和人体健康的危害,开发了以磷酸-硫酸为基液的无烟化学抛光技术.该技术的关键是在基础液中添加一些具有特殊作用的化合物来替代硝酸,在H3PO4(85%):H2SO4(98%)=(2.5～3.0):1.0,ρ(Al3 )=5～12 g/L,复合添加剂量为3～8 g/L,温度为95～115 ℃,时间为2.5～4.0 min的条件下,可以提高化学抛光质量,抑制铝材的点蚀,减缓全面腐蚀,获得较好的抛光效果.     

铝及铝合金高亮度无黄烟化学抛光工艺

从化学抛光机理入手 ,通过大量试验得到高亮度的无黄烟化学抛光添加剂及相应的抛光工艺 ,在消除黄烟污染的前提下提高了无烟化学抛光的亮度 ,同时用电化学方法对添加剂机理进行了分析。     

铝合金表面碱性化学抛光液组分的最佳浓度

铝合金碱性化学抛光效果较酸性抛光的差,为此,研究了低温下铝合金碱性化学抛光基础液及添加剂的最佳浓度。结果表明:以250g/L氢氧化钠、150g/L硝酸钠、15g/L硅酸钠、13g/L氟化钾为基础组分,分别加入30g/L硫脲、2g/L十二烷基硫酸钠、1.0g/L硫酸铜都可以使抛光效果得到提升,但加入30g/L硫脲效果更好,可以使铝合金抛光后的光泽度达到274 Gs,单位面积消耗量达0.01643kg/m~2。该工艺具有无污染、抛光光泽度高、操作简便等特点。     

不锈钢化学抛光工艺研究

研究了以硫酸为主的不锈钢化学抛光工艺。通过改变温度考察其对不锈钢抛光效果的影响，从而确定最佳温度范围；通过改变不锈钢化学抛光工艺中各组成的含量，考察其对抛光效果的影响，筛选出既有较好抛光效果、抛光成本也较低的最佳化学抛光工艺为：H2SO4 20％-30％，HNO3 3％-6％，添加剂3％-6％，水余量，温度60-70℃，时间3-5min。     

稀土对Al-Zn-M g-Cu/Al2O3陶瓷界面润湿性的影响

采用真空座滴法和熔铸法研究了在Al-Zn-Mg-Cu 合金中加入稀土(Ce、Y) 对Al2Zn2M g2Cu/Al₂O₃陶瓷界面润湿性的影响。结果表明,Al-Zn-Mg-Cu 合金中加入稀土可有效降低铝合金/Al₂O₃界面的接触角, 改善界面结合状态; 稀土改善界面润湿性存在一最佳含量范围, 添加Ce 的最佳含量约为0. 5w t% , Y 约为0. 7w t%。稀土改善润湿性的作用主要是稀土与Al₂O₃膜、Al₂O₃陶瓷发生反应。Mg、Zn、Cu 等合金元素在界面富集并参与界面反应对润湿性有利; 稀土与Mg、Zn、Cu 等合金元素适当组合改善润湿性的效果比单一稀土明显。      

高硅铝合金无烟化学抛光剂的研制

目前以H3PO4、H2SO4为基础的两酸无烟化学抛光体系对高硅铝合金的抛光效果不理想。在磷酸+硫酸+双氧水的基础液中,添加一定量的硫酸铁、三氧化二铬以及过硫酸铵,考察了不同质量的添加物对6063高硅铝合金化学抛光效果的影响。采用简单正交试验方式,以试样的反光率及麻点数量表征试样的抛光效果,优选了较优的抛光液成分。结果表明:按硫酸(85%)10 m L、磷酸(95%)20 m L、双氧水2 m L、硫酸铁0.1 g、三氧化二铬0.1 g、过硫酸铵0.1 g配制的抛光液抛光效果最佳。     

Cu2+对铝阳极氧化膜电解着色效果及耐蚀性的影响

1 前言 铝合金两步阳极氧化着色法(浅田法)已在机械、电子、建筑、航空领域得到广泛应用.在生产中,着色液特别容易受到Cu2+的污染,使着色效果发生变化,降低膜的耐蚀性,严重影响产品质量.本文以Ni2+盐电解液为着色体系,研究了Cu2+对着色效果及膜层耐蚀性的影响,并对Cu2+的影响原因作了初步探讨.     

Cu2+对铝阳极氧化膜电解着色效果及耐蚀性的影响

1 前言 铝合金两步阳极氧化着色法(浅田法)已在机械、电子、建筑、航空领域得到广泛应用.在生产中,着色液特别容易受到Cu2+的污染,使着色效果发生变化,降低膜的耐蚀性,严重影响产品质量.本文以Ni2+盐电解液为着色体系,研究了Cu2+对着色效果及膜层耐蚀性的影响,并对Cu2+的影响原因作了初步探讨.     

铝材无烟化学抛光工艺及其推广应用

铝材除机械抛光外,电化学抛光和三酸化学抛光都能达到相当满意的光亮度,但电解抛 光能耗大,六价铬废水难处理,三酸化学抛光产生的氮氧化物黄烟严重损害工人身体健康, 污染大气。长期以来,人们一直在努力寻求能够取代三酸化学抛光的无烟化学抛光工艺,然 而至今没有见到真正成熟稳定的工艺应用于工业生产,只有零星的、局部的、阶段性的应用 。显然,铝材无烟化学抛光工艺要成为一门普遍推广应用的技术,不但需要工艺本身的提高 ,还需要为人们所认识和掌握。 1 无烟化学抛光工艺鉴于铝材无烟化学抛光工艺的社会需求,我所于1997年承担…     

复杂结构微晶玻璃光学零件化学抛光技术

针对激光陀螺光学腔体这种复杂结构的光学零件,采用传统的光学抛光的方法无法对其凹槽、孔道进行抛光的问题,提出了一种采用化学溶液对玻璃进行侵蚀的化学抛光技术.本文分析了微晶玻璃的组成及化学抛光的机理,制备了适合的化学抛光溶液,设计了抛光技术方案、工艺流程及方法.对化学抛光后的光学表面进行了测试、分析,结果表明:采用NH4H...     

改性沸石对电镀废水中Pb2+、Zn2+、Ni2+的吸附

将天然沸石进行处理制备出多孔质改性沸石颗粒。在静态条件下，研究了改性沸石颗粒对重金属离子Pb^2 ,Zn^2 ,Ni^2 的吸附效果及条件，含Pb^2 ,Zn^2 ,Ni^2 的电镀废水经改性沸石颗粒吸附后，废水中Pb^2 ,Zn^2 ,Ni^2 的含量低于国家排放标准。     

Observable effects of Ca2+ buffers on local Ca2+ signals

Calcium signals participate in a large variety of physiological processes. In many instances, they involve calcium entry through inositol 1,4,5-trisphosphate (IP(3)) receptors (IP(3)Rs), which are usually organized in clusters. Recent high-resolution optical experiments by Smith & Parker have provided new information on Ca(2+) release from clustered IP(3)Rs. In the present paper, we use the model recently introduced by Solovey & Ponce Dawson to determine how the distribution of the number of IP(3)Rs that become open during a localized release event may change by the presence of Ca(2+) buffers, substances that react with Ca(2+), altering its concentration and transport properties. We then discuss how buffer properties could be extracted from the observation of local signals.     

ESR of Cu2+and Tl2+ in thallium borate glasses

The electron spin resonance (ESR) and optical absorption spectra of Cu²⁺ were measured in thallium borate glasses in order to investigate the effects of glass transition temperature,T _g, upon the responses of cupric ion in alkali borate glasses. The ESR of Tl²⁺ induced by-ray irradiation was also obtained. An abrupt increase in the covalency of in-plane Cu²⁺-O-bonding was observed in the Tl₂O system as well as in the Na₂O system in a similar B₂O₃ composition range althoughT _g for the Tl₂O glasses has little dependency on the composition compared with the Na₂O glasses. The trend in the variation of the S-character of the Tl²⁺ unpaired electron with composition agreed with that of the covalency of in-plane Cu²⁺-O-bonding. The structure of the anion group present in Tl₂O glasses was also examined by laser reman spectroscopy.     

酸改性膨润土吸附去除镍镉离子的研究

在静态条件下,研究了改性膨润土对重金属离子的吸附性能和吸附机理,着重探讨了改性膨润土去除模拟水样中重金属离子Ni2 ,Cd2 的适宜条件及改性膨润土的再生方法.结果表明,改性膨润土对Ni2 ,Cd2 具有较好的吸附性能;pH值是影响改性膨润土对重金属离子吸附的重要因素,不同的金属离子都有其适宜的pH值范围.吸附的最佳条件是pH值5.0～7.0,废水中Ni2 ,Cd2 含量不大于45 mg/L,搅拌时间约60 min.利用改性膨润土吸附处理Ni2 ,Cd2 含量小于45 mg/L的模拟水样,效果很好,Ni2 ,Cd2 的去除率均可分别达到98.5%以上,出水可达到国家排放标准.     

胶团强化超滤中SDS胶团对Cd^2＋，Zn^2＋和Pb^2＋的竞争吸附

胶团强化超滤法是一种将表面活性剂技术和超滤技术结合的新型、高效的重金属废水治理方法.以十二烷基硫酸钠(SDS)为表面活性剂,对含单一镉、锌、铅溶质以及混合溶质体系进行了胶团强化超滤研究,考察了胶团对Cd2 ,Zn2 ,Pb2 的竞争吸附性能.研究发现,当溶液中多种二价重金属离子存在时,各离子之间存在与SDS胶团的竞争吸附,竞争能力为Pb2 ＞Zn2 ＞Cd2 ;Cd-Zn有明显的协同吸附效应,而Cd-Pb,Zn-Pb则表现为拮抗吸附.     

锰矿尾渣对Cu2+和Ni2+的吸附性能研究

研究了锰矿尾渣对重金属离子Cu2 和Ni2 的吸附性能,分析了锰矿尾渣的吸附动力学,就吸附时间、Cu2 和Ni2 浓度及pH值等因素对锰矿尾渣吸附性能的影响作了系统考察,并对锰矿尾渣的吸附机理进行了初步探讨.结果表明,在温度为25°℃、pH值为7.5的条件下,锰矿尾渣对Cu2 和Ni2 的吸附容量可达到1.6 mg/g以上,去除率均可达到97.5%以上,适宜于处理含低浓度Cu2 或Ni2 的废水.锰矿尾渣的吸附机理为离子交换吸附和表面配位吸附.     

Phase Composition of the Products of Fe Oxidation in Fe + C + NaCl + H2O + O2 Exothermic Mixtures

Using thermodynamic analysis of the Fe–C–NaCl–H₂O–O₂ system and experimental studies (x-ray diffraction and Mössbauer spectroscopy) of exothermic mixtures containing Fe metal, activated carbon, water, and NaCl, we identified the state of Fe and determined the phase composition of the reaction products at different stages of oxidation with atmospheric oxygen. The calculation and experimental results are in reasonable agreement. Under the conditions of restricted access for air, the main oxidation product is magnetite, Fe₃O₄. Free access for air leads to the formation of hydrous ferric oxide, Fe₂O₃ · nH₂O. The most stable phase under the conditions of interest is goethite, Fe₂O₃ · H₂O (-FeOOH). Storage of incompletely oxidized samples away from air for 7–14 days leads to partial reduction of iron(III) oxide phases to Fe₃O₄ and -Fe.     

Characterization of various Eu2+ sites in Ca2SiO4:Eu2+ and Ba2SiO4:Eu2+ by high-pressure spectroscopy

Photoluminescence of Ba₂SiO₄ and Ca₂SiO₄ activated with Eu²⁺ was investigated at various temperatures (from 10 K to 300 K) and pressures (from ambient to 200 kbar). At ambient pressure and room temperature, under UV excitation both phosphors yielded a green emission band with maxima at 505 nm and 510 nm for Ba₂SiO₄ and Ca₂SiO₄, respectively. The energies of these bands depended on pressure; the pressure shifts were ?12:55 cm^?1/kbar for Ba₂SiO₄:Eu²⁺; and ?5:59 cm^?1/kbar for Ca₂SiO₄:Eu²⁺. In the case of Ca₂SiO₄:Eu²⁺, we observed additional broadband emission at lower energies with a maximum at 610 nm (orange band). The orange and green emission in Ca₂SiO₄:Eu²⁺ had different excitation spectra: the green band could be excited at wavelengths shorter than 470 nm, whereas the orange band — at wavelengths shorter than 520 nm. The pressure caused a red shift of orange emission of 7.83 cm^?1/kbar. The emission peaked at 510 nm was attributed to the 4f⁶5d→4f⁷(⁸S₇₌₂) transition of Eu²⁺ in the β — Ca₂SiO₄:Eu²⁺ phase, whereas the emission peaked at 610 nm — to the γ — Ca₂SiO₄:Eu²⁺ phase. The emission of Ba₂SiO₄:Eu²⁺ peaked at 505 nm was attributed to the 4f⁶5d→ 4f⁷(⁸S_7/2) transition of Eu²⁺ in the β — Ba₂SiO₄ phase.     

NpO 2 + -UO 2 2+ cation-cation interaction in NaCl-KCl-CsCl and LiCl-KCl-CsCl eutectic melts

Absorption spectra of the NpO ₂ ⁺ ion in UO ₂ ²⁺ -containing NaCl-KCl-CsCl (0.300:0.245:0.455) and LiCl-KCl-CsCl (0.575:0.165:0.260) eutectic melts in the region of the 5f-5f transitions, 700–2000 nm, were studied at 650 and 500°C, respectively. Processing of the spectra allowed the previously discovered phenomenon, cation-cation interaction of actinides in melts, to be interpreted for the first time in terms of the mass action law. It was shown that, at the concentrations of the interacting components studied (C _Np = 0.2 M and C _U = 0.1–2 M), a 1: 1 NpO ₂ ⁺ ·UO ₂ ²⁺ cation-cation complex is formed. Its concentration stability constant was estimated at 0.06(6) and 0.11 1 mol^?1 for the NaCl-KCl-CsCl and LiCl-KCl-CsCl systems, respectively.