Low concentration short time ozonation of rapeseed seeds reduces the stability of the oil and content of some antioxidant components

Ozonation is an innovative way to preserve high quality of seed during storage and it is an alternative to harmful organophosphorus agents. Disclosure of changes in the rapeseed oil under the influence of oxidative action of ozone on the seeds was the aim of the work and is presented for the first time. Two ozone concentrations and different length of ozonation were applied. The changes in tocopherols, phenolics, flavonoids contents, antiradical activity and oxidative stability were examined. The average vitamin E concentration was 33 mg per 100 g of oil before and 31.7 after ozonation of seeds. The average content of phenolic compounds was 14.3 mg of sinapic acid g⁻¹ and 16.9 after the ozone treatment. Changes in the flavonoids content and antioxidant activity were observed too. Ozonation caused a decrease in the vitamin E concentration which resulted also in reducing the quenching of free radicals and reduction of oil induction time.     

Comparison between photocatalytic ozonation and other oxidation processes for the removal of phenols from water

Photocatalytic ozonation (1O₃ + VUV + TiO₂), ozonation (O₃), catalytic ozonation (O₃ + TiO₂), ozone photolysis (O₃ + VUV), photocatalysis (TiO₂ + VUV) and photolysis (VUV) have been compared in terms of formation of intermediates, extent of, mineralization (TOC, COD, chloride, nitrate) and kinetics in the aqueous treatment of three phenols (phenol, p‐chlorophenol and p‐nitrophenol). In all cases, photocatalytic ozonation led to lower degradation times for chemical oxygen demand and total organic carbon removal. Intermediates formed were similar in the different oxidation systems with some exceptions. They can be classified into three different types: polyphenols (resorcinol, catechol, hydroquinone), unsaturated carboxylic acids (maleic and fumaric acids) and saturated carboxylic acids (glyoxylic, formic and oxalic acids). First order kinetic equations have been checked for the oxidation processes studied in the case of the parent compound. Rate constants of these systems have also been calculated. Copyright © 2005 Society of Chemical Industry     

The greenhouse effect; Impact upon and the role to be played by construction

The authors highlight several possible ways in which the construction industry could lower present emissions of the greenhouse gas, carbon dioxide. It is an excellent discussion document and is recommended reading.     

轧钢加热炉汽化冷却余热的合理利用技术

针对加热炉汽化冷却系统所产饱和蒸汽在非采暖期大量放散的现状，通过实例提出可用这类蒸汽制冷，作为夏季某些单位空调之用。这样就可以用较少的投资解决非采暖期的汽冷余热浪费问题，合理利用热能，降低轧钢成本。     

臭氧法水处理在空调冷却水系统中的应用

探讨了臭氧法杀菌灭藻，缓蚀，阻垢的机理，认为臭氧法可用于空调冷却水处理，并给出在工程设计中的应用方法。     

浅析中央空调系统替代制冷剂的选择

根据大气臭氧层耗损和温室气体对全球气候变化的影响，分析了中央空调系统几种替代制冷剂的特性，探讨了在实际使用中如何进行替代制冷剂的选择。     

臭氧在食品加工用水处理工程上的应用

本文叙述了臭氧的一些特性 ,并以烟台某食品加工公司食品加工用水处理工程为例 ,介绍了臭氧的产生及应用情况 ,提供了处理前后水中各项指标的对照     

重型车床专用喷吸钻的设计

主要介绍了喷吸钻装置的工作原理、结构设计和使用特点,并对其运行的可靠性作简要分析.此喷吸钻的设计目的主要是为了解决大型轴类(轧辊类)工件的深孔加工问题,提高实际生产中的深孔加工效率.     

Exergy losses in refrigerating systems. A study for performance comparisons in compressor and condenser

A study is carried out to describe irreversibilities in one stage refrigerating process for vapour compression cycle with refrigerant mixtures R-404A, R-410A, R-410B and R-507 as working fluids. They are calculated as exergy losses by an algorithm developed on the basis of thermodynamics. The proposed relationships have been derived from exergy balances on the system components. Emphasis is placed on parameters influencing the losses and the related results are presented through Grassmann diagrams (diagrams of exergy fluxes). Furthermore, detailed information on the variation of cycle's exergy efficiency with evaporating and condensing temperatures is given. Copyright © 2003 John Wiley & Sons, Ltd.     

臭氧纳米气泡对水中三价砷的氧化效果

砷污染防治技术,将三价砷[As(Ⅲ)]先氧化成五价砷[As(Ⅴ)]是保证治理效果的必要手段。文中为了提高臭氧氧化效果,将臭氧以纳米气泡(NBs)的形式通入水中。在不同As(Ⅲ)初始浓度、不同pH下,NBs系统对As(Ⅲ)氧化率均远远高于臭氧大气泡系统,最高可达96.5%[对应As(Ⅲ)初始浓度为0.2mg/L],比大气泡系统提高了44.47%。NBs系统对As(Ⅲ)的氧化率随初始浓度的增大而有略微提高。溶液初始pH值为3、9时,NBs系统对As(Ⅲ)的最高氧化率达95.1%、94.2%,高于pH值为7时的氧化率;碳酸根离子对臭氧大气泡和NBs系统均具有一定的促进作用,添加了碳酸钠的NBs系统对As(Ⅲ)的氧化率达97.8%,比未添加药剂的系统提高了1.8%。