ICP-AES法测定磷铜合金中的磷

对电感耦合等离子体原子发射光谱（ICP-AES）法测定磷铜合金中磷的主要条件及效果进行试验,采用硝酸溶解试料,进行溶样条件的选择、谱线选择及干扰校正,在最佳的试验条件下对磷铜合金中的高含量磷进行测定。试验结果与传统磷钼酸铵沉淀酸碱滴定法的结果进行比较得出,采用ICP-AES法不仅分析数据具有很好的一致性、较高的准确度和精密度,并且具有快速、高效等优点。     

磷钼酸喹啉氧化还原容量法测定磷

磷钼酸和喹啉在强酸性介质中生成的磷钼酸喹啉沉淀,已广泛用于酸碱容量法测定磷.该法的特点是:沉淀的溶解度小,选择性好,灵敏度高,对于高含量磷的测定,精确度较高,但该法的缺点是:空白高,硅的干扰较严重,特别是硅高的时候,沉淀不易洗涤干净,整个流程需连续进行,方法较难掌握,分析结果系统偏高,不适用于微量磷的测定,也不适用于含硅高的矿石中磷的测定.本文介绍的磷钼酸喹啉氧化还原容量法是在硝酸盐酸混酸介质中使磷生成磷钼酸喹啉沉淀,在盐酸介质中,存在草酸及煮沸情况下用硫酸联胺将钼(Ⅵ)还原为钼(Ⅴ),     

铋磷钼蓝分光光度法测定钛白粉中磷

钛白粉中大量存在的钛在分解时易水解形成较细的沉淀,即使反复过滤,滤液中都残留有少量细小沉淀颗粒,故而会影响光度法对磷的测定。针对这一问题,实验采用无水碳酸钠和硼酸混合熔剂熔融钛白粉试样,再加入硫酸中低温溶解熔融样,然后在硫酸介质中,加入高锰酸钾将磷氧化为正磷酸根的形式存在于溶液中,加入氢氧化钠与基体钛反应生成三钛酸钠沉淀,过滤,实现了钛与磷的分离,从而建立了铋磷钼蓝光度法测定钛白粉中磷的测定方法。在优化的实验条件下,磷质量浓度在0.009～0.382 μg/mL范围内与其吸光度符合比尔定律,校准曲线的相关系数为0.999 9。采用实验方法对钛白粉样品进行8次平行测定,结果的相对标准偏差(RSD,n=8)小于4.0%,回收率在98%～103%之间。采用微波消解-电感耦合等离子体质谱法(ICP-MS)进行方法对照试验,结果表明两种方法的测定结果基本一致。     

磷铁合金中磷测定方法的改进

用硝酸、氢氟酸溶解试样后，加高氯酸加热蒸发至冒浓白烟以除去硅和氟，借此将亚磷酸氧化为正磷酸，以钒钼黄光度法代替磷钼酸铵沉淀酸碱中和滴定法快速测定磷铁合金中磷含量，取得了较好效果，方法具有简便、快速、准确的优点。     

磷铁中磷的直接光度法

磷铁中磷的含量一般在１５～２５％之间，其测定方法大多以重量法和容量法为主，手续繁琐，分析周期长。本法试用王水液样，经高氯酸二次强性氧化，使样品得到完全分解，并将磷氧化为高价，在硝酸介质中，磷与钒酸铵和钼酸铵生成可溶性的磷钒铂黄色络合物，测其吸光度。该法简便、快速，易于掌握，结果准确。     

铜银磷焊料中磷的快速测定

铜银磷合金中磷的测定,过去一直沿用磷酸铵镁沉淀法,但该法不易掌握,分析结果波动较大。本文介绍在适宜酸度下,准确加入一定过量的硝酸铋使磷沉淀完全,过剩的铋盐在硝酸介质中用EDTA直接滴定。 通过试验,沉淀酸度对测定结果十分重要,酸度在0.7～1N之间,测定结果非常稳定,低于0.7N,硝酸铋就会水解,高于1N,磷酸铋沉淀不完全,超过1.5N沉淀极少,2N时几乎不沉淀,另外滴定终点也是在0.7～1N间反应最敏锐。测定10～60mg磷,回收率为99.3～100.7％,标准偏差0.11％,相对标准偏差(11次测定     

增压溶样磷钼酸喹啉滴定法测定磷铁中磷

磷铁中磷的测定,一般采用王水溶样或碱熔试样。在硝酸介质中,使磷与钼酸铵生成磷钼酸铵黄色沉淀,过滤后用氢氧化钠标准溶液溶解,以酚酞为指示剂,用硝酸标准溶液回滴过量的氢氧化钠。在常压下酸溶解试样时,溶样时间长,酸耗大,样品溶解不完全,使结果偏低;使用碱熔...     

微波消解—ICP发射光谱法测定磷铁中锰、磷

介绍了在一个密闭容器中用微波消解制备样品溶液，结合ICP发射光谱法，对磷铁中锰、磷同时测定的方法。与传统的样品制备过程相比较，微波消解方法制备样品更快速简便，其结果与传统方法的测量结果有很好的一致性。     

磷铁中磷的快速测定—磷钼兰高速比色法

本文提出磷铁中磷的快速测定方法，方法准确简便。     

磷钼蓝光度法快速测定生铁中的磷

对生铁中磷含量的快速测定进行改进，选用稀HNO3溶解试样，采用磷钼蓝光度法进行测定，实现了提高分析速度、提高结果的灵敏度、稳定性和准确度的目标。     

Deposition of immersion coatings on steel tire cord

The deposition of immersion coatings of Cu-Sn alloy from sulfuric-acid solution onto steel tire cord is investigated. The influence of the cord speed in the bath on the alloy’s chemical composition and deposition rate is considered. The concentration of the solution’s basic components is determined, and their influence on the deposition rate and composition of the coating is discussed. The upper limit on the Fe²⁺-ion concentration in the solution is established.     

Study on Electrodeposition of Ho-Co Alloy in Dimethylsulfoxide

Ｎｏｗｒａｒｅｅａｒｔｈｓ ｉｒｏｎａｌｌｏｙｓａｒｅｐｒｏｄｕｃｅｄｍａｉｎｌｙｂｙｖａｃｕｕｍｅｖａｐｏｒａｔｉｏｎ ,ｃａｔｈｏｄｅｓｐｕｔ ｔｅｒｉｎｇｏｒｉｏｎｐｌａｔｉｎｇ ,ｗｈｅｒｅｔｈｅｃｏｓｔｉｓｈｉｇｈａｎｄｔｈｅｔｅｃｈｎｏｌｏｇｙｉｓｃｏｍｐｌｉｃａｔｅｄ .Ｅｌｅｃｔｒｏｄｅ ｐｏｓｉｔｉｏｎｍａｙｂｅａｃｏｍｐａｒａｔｉｖｅｌｙｇｏｏｄｗａｙｆｏｒｉｔｓｌｏｗｃｏｓｔａｎｄｓｉｍｐｌｅｔｅｃｈｎｏｌｏｇｙ .Ｈｏｗｅｖｅｒｉｔｉｓｄｉｆｆｉｃｕｌｔｔｏｅｌｅｃｔｒｏｄｅｐｏｓ…     

脉冲镀与直流镀对镀铁层性能的影响

为研究脉冲镀与直流镀对镀层特性的影响,论文通过对电镀机理的分析和镀铁层特性的比较,总结了脉冲镀较直流镀的优越性;在同一电镀液配比条件下,脉冲镀铁层的沉积状态略优于直流镀铁层,镀层硬度、抗腐蚀性、表面形貌和结晶度均优于直流镀层。     

Critical ageing of hydroxyapatite sol-gel solutions

It has been established that hydroxyapatite coatings can be produced using an alkoxide based sol-gel technique. Previous work showed that in addition to hydroxyapatite other phases including CaO were observed. A critical factor in determining the composition of the final coating is the period between solution preparation and coating deposition. The current study addresses how the ageing time affects the composition of the coating and the time required before a solution can be used to deposit monophasic coatings. Powders and coatings were produced with ageing times up to one week and examined with X-ray diffraction, thermal gravimetric analysis and differential thermal analysis. By depositing coatings after various ageing times, it was found that a solution ageing time of at least 1 day was required before monophasic hydroxyapatite coatings could be deposited. Thermogravimetric analysis showed that heating of the gel in air or in nitrogen both produced hydroxyapatite. Thermogravimetric analysis could be used as a simple and effective tool for identifying the critical ageing time required to produce high-purity hydroxyapatite coatings.     

电沉积法从含金废液中回收金的试验研究

在自制的电解槽内,利用电沉积法进行含金废液中金的回收试验,分别考察电流密度、流速、pH、Na2SO3浓度等因素对金电沉积速率的影响。结果表明：电流密度是影响金电沉积速率的主要因素,电流密度越大,沉积速率也就越快;流速和pH对金沉积速率影响较小;加入2 g/L的Na2SO3后,电沉积效率有明显的提高。     

DT碳化钨钢结硬质合金显微组织结构的研究

通过对DT合金各相的成份、形貌、结构特点的观罕及热处理工艺对其影响的分析,揭示出该合金的显微特征,并就进一步提高合金性能从理论上进行了初步探讨。碳化钨相与基体相在加热到高温时发生相互溶解和扩散。各元素的分布有一定的规律。扩散的结果强化了两相的结合。碳化钨相存在溶解、析出和长大倾向不同的两种颗粒,它们的形貌和成份均不同,一种是W向基体扩散较多、外形已明显"球化"的颗粒;另一种是W向基体扩散较少,外形尚未明显"球化"的颗粒。通过比较认为:若能使合金中碳化钨相颗粒实现"球化,"可能有利于提高性能。固溶有其他元素的碳化钨相仍保持WC的结构类型,但晶格常数大于WC,而且随回火温度提高,晶格常数a和c减小。     

Study on Electrochemical Characteristics of Electroless Co-Ni-B Alloy with Cerium

The effects of rare earth element cerium on composition and electrochemical characteristics of electroless Co-Ni-B alloy were studied in this paper. The alloy component was analyzed using Inductively Coupled Plasma (ICP). The plating rate is was determined by electronic balance. The cathode polarization curves and cyclic voltammogram during the electroless deposition were tested by LK998Ⅱmodel electrochemical analytical system. The results show that rare earth element Ce can co-deposit with cobalt-based alloy, and with mass increase of Ce added in aqueous solution, the contents of Co, Ni, Ce in alloy increase and the content of B decreases. Ce can increase deposition rate of alloy in some range. The rare earth makes deposition potential move to positive direction and makes polarizability decrease.     

The deposition of cobalt on iron powder by means of the cementation reaction

A preliminary investigation has been undertaken of the feasibility of depositing cobalt on iron powder by means of the cementation reaction. Three different solutions were considered, cobalt chloride, cobalt sulphate and cobalt nitrate. No attempt was made to control the pH although its value was monitored during the cementation reaction. The most successful salt type was found to be the chloride which gave conversions of approximately 80% from a solution that contained 150 gl⁻¹ CoCl₂·6H₂O at 70°C. The morphology of the cemented particles appeared to be independent of the type of cobalt salt used, although the rates of deposition were significantly influenced by the type of anion in solution. The cemented product appeared to nucleate heterogeneously at discrete cathodic sites on the iron-particle surface as a fine nodular deposit. These nodules eventually grew and coalesced to form a porous coating, leaving a residual iron core in the centre of the particle. Cessation of cobalt deposition occurred when the mean particle-coating composition attained approximately 80 wt% Co, 20 wt% Fe. At this stage the iron cores of the particles still had access to the solution through long, narrow, interconnecting channels within the deposit. The solution still possessed a relatively high concentration of cobalt so depletion of this cation was not responsible for cessation of the cementation reaction.     

Feasibility of producing cadmium-zinc alloy powders

Conclusions Electrolytic deposition of cadmium-zinc alloy powders from sulfate solutions is possible provided that the reduction of cadmium ions is performed under limiting diffusion current conditions. Simultaneous discharge of cadmium and zinc ions is not accompanied by super- and depolarization phenomena, which enables the alloy composition to be predicted using polarization curves of reduction of the two kinds of ion in individual solutions. Because of growth of the alloy deposit surface during galvanostatic deposition, the composition of the powder is a function of buildup time, and can be changed only by varying the solution composition. Consequently, it is best to produce such powders either under potentiostatic conditions or under galvanostatic conditions but with continual removal of deposited powder from the basis.Translated from Poroshkovaya Metallurgiya, No. 8 (272), pp. 6–10, August, 1985.     

Accelerated study on lysozyme deposition on poly(HEMA) contact lenses

A technique was developed to accelerate lysozyme deposition on poly(HEMA) contact lenses and measure the amounts of the deposited lysozyme. This technique was for evaluation of bendazac lysine solution, a contact lens cleaning and wetting solution. Effect of temperature on lysozyme deposition on poly(HEMA) contact lenses was examined. Five temperatures ranging from 25 degrees C to 90 degrees C were chosen to examine the temperature effect. The amounts of lysozyme deposited on poly(HEMA) contact lenses at 25 C and 60 C were 0.27 microg/lens and 0.61 microg/lens, respectively. The amount increased sharply to 23 microg/lens at 70 degrees C with the maximum of 31 microg/lens at 90 degrees C. Kinetics of lysozyme deposition on poly(HEMA) contact lenses was examined at 80 degrees C. Lysozyme deposition increased sharply during the first 2 h and reached a plateau after 2 h. Effectiveness of various cleaning procedures was examined using bendazac lysine solution. When the contact lenses were washed without rubbing with fingers, the bendazac lysine reduced the amount of deposited lysozyme by more than 40% from 18.3 microg/lens to 10.6 microg/lens. The effect of bendazac lysine was most prominent when the contact lenses were shaken during storage in the presence of lysozyme in solution. If the contact lenses were cleaned by rubbing with fingers, the effect of bendazac lysine solution on the prevention of lysozyme deposition was negligible.