钛在轮椅中的应用

本文主要介绍了钛在轮椅中的应用,对比了轮椅用几种材料的优缺点,总结了钛制轮椅的特点及国内外市场开发情况.     

醋酸环境下的钛合金腐蚀分析

本文针对化工厂醋酸装置用钛合金设备的腐蚀和断裂原因进行了分析,从实验的结果来看,钛合金螺母断裂为应力腐蚀开裂所致,而在还原性缺氧以及副反应中有氢生成的情况下,会出现点蚀和严重的整体腐蚀,在该环境中采用增厚钛合金表面氧化层的方法并不能有效解决腐蚀问题。     

硅藻土在钛液过滤中的应用

硅藻土助滤剂在钛液过滤中的应用操作分两步进行： 一、预涂 预涂即在钛液过滤操作之前，预先把硅藻土助滤剂涂于过滤介质即滤布之上。[第一段]     

钛在汽车工业中的应用及降低钛材成本的工艺

叙述了钛在减轻汽车自重、节约燃油、保护环境、降低噪声、提高汽车性能方面的优势和应用领域及趋势。介绍并评价了几种降低海绵钛与钛材成本的工艺技术。     

钛弹簧在汽车中的应用

随着钛材的普及,钛制品的产品越来越受到人们的喜爱,钛弹簧具有高弹性、高强度,高塑性,和钢制弹簧相比有较好的抗疲劳性。钛合金具有较高的比强、较低的弹性模量,因此是一种理想的弹簧材料。与钢弹簧相比,钛弹簧具有重量轻、体积小和共振频率高等优点,其密度和弹性模量只有钢簧的一半,而强度几乎与钢弹簧一样。由于具有这些特点,     

钛在航空工业中的应用及趋势

钛及其合金具有比重小、比强度高、耐腐蚀、高低温性能好等突出的优点，而被人们称为“太空金属”和“海洋金属”，在航空、航天、舰船、兵器、石油、化工、医疗等等领域得到广泛的应用，受到了全世界的高度重视。     

浅谈醋酸片的保存环境

我国乃至世界各国电影资料馆中保存数量最多的电影胶片为以醋酸纤维素酯为片基材料的"安全片",其在保存过程中易发生霉变、醋酸综合症等病害现象,严重影响电影胶片的保存。本文综述了醋酸片产生醋酸综合症以及霉变的主要原因与危害,以及醋酸片在保存过程中应该注意的一些问题。     

浅谈醋酸片的保存环境

我国乃至世界各国电影资料馆中保存数量最多的电影胶片为以醋酸纤维素酯为片基材料的“安全片”,其在保存过程中易发生霉变、醋酸综合症等病害现象,严重影响电影胶片的保存。本文综述了醋酸片产生醋酸综合症以及霉变的主要原因与危害,以及醋酸片在保存过程中应该注意的一些问题。     

钛材在海军工程中的应用及需要解决的问题

概括地介绍了国内外海军工程应用钛材的情况,分析了目前存在的问题及解决这些问题的对策。我国钛材产量已达万t水平,合金种类,材料品种规格等已经达到了在海军工程中大量应用的条件。     

醋酸对明胶-壳聚糖膜性质的影响及应用

目的制备基于不同醋酸质量分数的明胶-壳聚糖基可食复合膜,以期探究醋酸质量分数(1%、1.5%、2%和2.5%)对复合膜性质及应用的影响。方法利用透湿仪、透氧仪、拉伸仪、扫描电镜、热重、红外和拉曼光谱探究可食性复合膜的理化性质,并进行机理解析。结果低醋酸浓度制备的复合膜具有较低透湿性和透氧性,且其抗拉强度和断裂伸长率较高;同时醋酸浓度较低时,可以提高复合膜表面的光滑度,改善复合膜的热稳定性。红外测试与拉曼测试表明,明胶、壳聚糖、醋酸之间主要是通过氢键进行相互作用并结合,从而形成了稳定致密的薄膜。结论以质量分数为1%醋酸制备得到的明胶-壳聚糖基复合膜,其性质表现得更加优异,同时该系列薄膜可以制备成包装袋并能有效包装花生,对明胶-壳聚糖复合膜在食品包装领域的应用具有一定的参考作用。     

Photolysis of Neptunium Ions in Acetic Acid Solutions

Radiochemistry - Photochemical reactions involving Np(VI) and Np(V) in 0.5–17.3 M CH3COOH (HAc) solutions have been studied. It was found that irradiation with UV light causes reduction of...     

Kinetics of Mild Steel Corrosion in Aqueous Acetic Acid Solutions

The kinetics of mild steel corrosion in aqueous acetic acid solution has been investigated by weight loss and polarization techniques at 25,35 and 45℃.The weight loss of mild steel at room temperature (25℃) has been found to be quite significant,indicating poor corrosion resistance in acetic acid.The maximum corrosion rate has been observed in 25% acetic acid solution at all three experimental temperatures.The decrease in corrosion rate after attaining a maximum value has been attributed to the deposition of corrosion product on the surface.Anodic polarization curves exhibit active behaviour at each concentration and temperature with a shift towards higher current density region and increased corrosion rates at higher temperatures.The cathodic polarization curves are almost identical irrespective either of the concentration of acetic acid or temperature.The results obtained by both the techniques are in good agreement,while the surface studies support the conclusions drawn from the weight loss method.     

醋酸菌菌膜生产工艺条件优化

目的 优化用醋酸菌生产菌膜的最适培养条件和方法,以期获得天然、安全的食品包装用膜的生产工艺。方法 以涩柿醋为原料,分离筛选出高产菌膜的优良醋酸菌种,通过单因素和Plackett?Burman 等试验设计优化醋酸菌菌膜最适培养方法和工艺条件。结果 从涩柿醋中分离纯化获得产膜醋酸菌,经鉴定为葡糖醋杆菌。用醋酸菌生产醋酸菌菌膜最优培养条件:蔗糖质量分数为5%、蛋白胨质量分数为0.7%、酵母提取物质量分数为1.2%、柠檬酸钠质量分数为0.15%、K2HPO4质量分数为0.16%、乙酸体积分数为1%、无水乙醇体积分数为2%,种龄为32 h,接种量为9%;培养5 d后,醋酸菌菌膜的平均产率为364.65 g/L,是优化前的(246.03 g/L)的1.48倍。湿膜平均含水率为99.38%,复水率为71.09%～83.39%,菌膜干膜复水率高且复水速度快,复水1 min其含水率便可达到70%以上。结论 醋酸菌用经过优化选择的培养液和方法,可生产出高质量的菌膜。     

Stability of Neptunium(V) in Concentrated Acetic Acid Solutions

Np(V) acetate in glacial acetic acid and aqueous acetic acid solutions is resistant to disproportiona-tion and occurs in equilibrium with the NpO₂(Ac)·H₂O precipitate. Within the time of dehydration with excess acetic anhydride, Np(V) disproportionates. The inverse reproportionation process occurs after adding excess water to anhydrous acetic acid containing acetic anhydride, Np(IV), and Np(VI). Addition of HClO₄ causes rapid disproportionation of Np(V) in anhydrous acetic acid and in concentrated acetic acid solutions. The spectra of suspensions containing Np(V) and potassium acetate in concentrated acetic acid contain absorption bands with maxima at 990 and 1020 nm, assigned to NpO₂(Ac)₃^2- anions and K₂NpO₂(Ac)₃ particles, respectively.

     

Corrosion Resistance of Bright Nickel Coatings in the Vapor of Acetic Acid

Materials Science - We study the corrosion behavior of bright nickel coatings in the vapor of concentrated acetic acid. Deposits with a sulfur content of 0.25 wt.% are obtained from electrolytes...     

Parameters of Oxidation-Reduction Processes in Ozonized Acid Media

We have studied the cathodic processes on a platinum electrode in ozonized sulfuric acid solutions of different concentrations. The kinetic parameters of corrosion processes have been determined. The cathodic processes on a platinum electrode in the presence of ozone are more intense by a factor of 1.5 than in the presence of oxygen. Ozone increases the possibility of chemical reaction with the help of generation of OH⁻ ions. In addition, we have proposed a scheme for the action of ozone in acid media.__________Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 40, No. 5, pp. 43–47, September– October, 2004.