深圳市线路板蚀刻废液中铜、砷、铅、汞、镉含量调查

对深圳市60家线路板企业含铜蚀刻废液中铜、砷、铅、汞、镉含量的检测结果显示:酸、碱性蚀刻废液铜含量范围分别为38.6～167.9g/L、53.7～171.8g/L,,通过测量比重推算铜含量适用于碱性废液但不适合酸性废液.56个样品可检出砷(大于3mg/L).56个样品未检出铅(小于5mg/L),其余4个铅含量偏高.所有样品汞、镉均未检出,含量分别小于4mg/L、0.3 mg/L.将各样品砷、铅、汞、镉含量实测值换算为铜含量100ga.时的相对值后发现,上述四元素在蚀刻废液中的正常值分别为＜12mgAs/L、＜5 mg Pb/L、＜4 mg Hg/L、＜0.3 mg Cd/L.     

废催化剂中稀有金属钼、钒回收工艺评述

阐述了稀有金属钼的回收方法：空白焙烧-浸出工艺，添加试剂焙烧-水浸工艺，氨浸法，直接氧化浸取法；钒资源的回收方法：无添加剂高温活化-弱碱浸取法，焙烧-水浸取法，还原酸溶-氧化浸取法，一段弱酸浸出-二段弱碱浸出法。并对废催化剂回收利用前号略作了分析。     

从废催化剂回收钨、钼、钴、铝的研究进展评述

评述了我国从废催化剂回收钨、钼、钴、铝的某些研究新进展,并提出多篇文献供参考.     

钛白废酸回收技术研究

通过臭氧氧化技术将钛白废酸中的Fe2 氧化成Fe3 ,再用萃取法除去Fe3 。考察了络合剂(盐酸)浓度、萃取剂、萃取相比和多级错流萃取级数等对Fe3 萃取率的影响,初步探索了反萃法回收萃取剂及萃取剂的循环利用。结果表明,当盐酸浓度为3.4～4.0mol/L时,几乎可完全络合溶液中的Fe3 ,Fe3 的萃取率随相比(O/W)的增加而增大,萃取级数愈多萃取效果愈好。O/W=1∶1的单级萃取与总相比O/W=0.5∶1的四级错流萃取率接近。当反萃相比(W/O)=1.5∶1时,Fe3 的反萃率达97%,萃取剂经过6次萃取—反萃循环后,Fe3 的萃取率没有明显下降。去除Fe3 后的钛白废酸,经蒸馏浓缩到70%左右,再与浓硫酸混合后可用于钛白粉的生产,蒸馏过程中得到的盐酸循环使用,反萃出来的Fe3 可作为生产铁红的原料。     

The relationship between motivation,learning approaches,academic performance and time spent

Previous literature calls for further investigation in terms of precedents and consequences of learning approaches (deep learning and surface learning). Motivation as precedent and time spent and academic performance as consequences are addressed in this paper. The study is administered in a first-year undergraduate course. Results show that the accounting students have a slightly higher score for deep learning compared to surface learning. Moreover, high intrinsic motivation and extrinsic motivation have a significant positive influence on deep learning. Next, deep learning leads to higher academic performance; surface learning on the other hand leads to lower academic performance. The effect of deep learning on performance still holds, when we control for time spent, gender and ability. Consequently we can conclude that a deep learning approach is much more than ‘simply’ spending a lot of time on studying.     

溶液法乙丙橡胶脱钒技术

乙丙橡胶脱催处理是其采用溶液聚合法制造工艺中的重要过程之一,旨在脱除残留在产品中的催化剂,保证产品质量稳定.主要论述了溶液聚合法工业生产乙丙橡胶的几种脱钒方法,如碱水洗涤法、水洗转相法、活性金属沉淀法、极性溶液萃取法、水油乳液法、酸洗水洗法等.     

干冰去污在核电站换料相关设施中应用方案的初步研究

干冰技术的去污效率高、基材损伤小、二次废物量少,在核设施的去污实践中越来越多的受到重视.由于核电站反应堆换料系统的去污比较常见,通过对反应堆换料水池、乏燃料贮存运输容器的去污需求分析,设计一套干冰去污装置,实现对核设施的有效去污,满足人员操作和设备运输的要求;其去污过程和最终二次废物产量也遵循了废物最小化的原则,且环保...     

Does a reward program affect customers’ behavioural intention of visiting the airport? A case study of Singapore Changi Airport

An understanding of the behavioural intentions of customers in visiting airports may help airport management to boost airport retail revenue (i.e. non-aeronautical revenue) by increasing customer spending at the airports. This study aims to examine the connection between airport reward programs and customers' behavioural intentions of visiting the airport, attempting to bring some benefits and credits for implementing reward programs in the airport sector by using Singapore Changi Airport as a case study. Two types of customer behavioural intentions (i.e. time spent at the airport and various purposes of visiting the airport) were investigated in the study to examine the effects of Changi Airport's reward program (i.e. Changi Rewards). An on-line survey was conducted, and the participants' responses were analysed via a structural equation modelling approach. The results showed that the attractive benefits of Changi Rewards could have a positive influence on arousing customers' intentions to engage with the programme. In addition, customers' intentions to engage with the programme can have a positive effect on increasing passengers' time spent at the airport and inducing customers to visit the airport for leisure purposes. Managerial implications to the airport sector are discussed.     

单中心聚烯烃催化剂的化学负载

本文介绍了近几年国内外在单中心聚烯烃催化剂负载化方面的研究进展.     

含油石化废催化剂低压脱油预处理研究

采用低压脱油的方法对含油石化废催化剂进行预处理研究,分别考察了温度、压力、保温时间、升温速率等条件对低压脱油过程的影响,确定低压脱油的最佳实验条件:加热终温550℃;压力2×104 Pa;升温速率9℃/min;保温时间1.0小时。在此条件下,可完全脱除废催化剂的油质。并研究了此脱油过程中硫的走向与尾气的处理。