大气颗粒物及其组成研究进展(上)

颗粒物是空气中最重要的污染物之一,由于颗粒物表面的吸附作用,其组分非常复杂,其中含有多种有毒有害的化学成分,对大气环境造成不良影响,并危及人体健康。借助大气颗粒物及其组成成分的测定,通过污染源解析分析其来源及影响因素,控制大气颗粒物的排放,对于保证大气环境质量、改善人们的生存环境具有重大意义。本文对此进行综述。着重介绍大气颗粒物及其组成成分、源解析及测量技术的最新进展。     

筛：卒姆托建筑观感

在走访了卒姆托设计的大多数建成作品后。笔者发现,他在很多项目中都通过不同构造方式的使用,对建筑所处环境中存在的诸多信息进行着过滤和筛选。这些有意识的筛选依托于对建造方式的实验,营造出令人印象深刻的空间氛围及体验。     

Synthesis of SiC whiskers by VLS and VS process

This study investigates the mechanisms of SiC whisker formation in the carbothermal reduction of quartz to SiC in different gas atmospheres. Reduction of quartz by graphite was studied in Ar, H₂, and CH₄–H₂–Ar gas mixture in a laboratory fixed bed reactor. The reduction products were characterised by XRD, SEM and TEM. Whiskers were not formed in the carbothermal reduction of quartz in argon. Two types of SiC whiskers were observed in the carbothermal reduction of quartz in H₂ and CH₄–H₂–Ar gas mixture. In the process of reduction at 1400–1600 °C in H₂ and at 1200–1600 °C in CH₄–H₂–Ar gas mixture, whiskers with hexagonal shape with diameter 100–800 nm and length up to tens of microns were formed by the VLS mechanism under catalytic effect of iron. The whiskers with the characteristics of cylindrical shape and high aspect ratio were synthesized in CH₄–H₂–Ar gas mixture at 1400–1600 °C by VS mechanism.     

AHP法用于大气环境评价

本文根据ＡＨＰ原理，以ＧＢ３０９５－８２大气环境质量标准作为基础，对大气环境质量进行综合评价。方法快速、简便，适合于多采样点多污染因子的评价任务。     

The effect of postharvest 1-MCP treatment and storage atmosphere on ‘Cripps Pink’ apple phenolics and antioxidant activity

This study investigated the effect of a postharvest 1-methylcyclopropene (1-MCP) treatment, controlled atmosphere and storage time on the total antioxidant activity (TAA) and phenolic compounds in the peel and flesh of ‘Cripps Pink’ apples (Malus domestica Borkh.). Preclimacteric apples were harvested and treated with 1-MCP then stored in normal atmosphere (NA) or controlled atmosphere (CA) at 0 °C for up to 160 days. In general, the level of phenolics decreased by 9% in the peel and significantly increased twofold in the flesh during cold storage, regardless of storage atmosphere or 1-MCP treatment. However, treatment with 1-MCP resulted in significantly lower concentrations of chlorogenic acid and procyanidin B2 in apple flesh, and catechin and epicatechin in the peel compared to the control fruits. There was no significant effect of CA on the phenolic compounds during long-term storage, except for quercetin 3-galactoside and quercetin 3-glucoside, which both significantly increased under CA storage. Total antioxidant activity (TAA) is an important nutritional attribute of apples in the human diet. The results showed that TAA in the peel tissue was about eight times higher than that of the flesh, with mean values of 4.75 g TE/kg FW and 0.56 TE/kg FW, respectively. The TAA in both the peel and flesh tissue increased significantly during storage by 40% and 70%, respectively. The storage atmosphere did not significantly affect TAA in either the peel or flesh, whilst the 1-MCP treatment significantly reduced the TAA in the peel tissue only. These results show the beneficial combined effects of pre-storage 1-MCP treatment and CA on ‘Cripps Pink’ apple phenolic composition and antioxidant capacity during long term storage.     

环境流体力学研究进展

本文对环境流体力学概念进行了介绍,总结了环境流体力学在水体、大气等不同条件下及工业生产中的运用情况,展望了今后环境流体力学的发展方向。     

微妙的时代性 对爱尔兰两代建筑师的思考

文章通过对爱尔兰的A2建筑师事务所和德博拉卡姆与米格尔建筑师事务所设计项目的比较,分析了爱尔兰两代有代表性的建筑师对建筑的意象、目的等理解的异同,以及由此引申开来的对环境、材料与工艺等在建筑创作中作用的不同思考。     

大气吸收系数的研究与应用

定义了大气吸收系数的概念．通过试验及理论分析．得出我国各地区大气吸收系数推荐值,并时体育场场地照明照皮计算进行修正。     

Avocado Fruit Quality Management during the Postharvest Supply Chain

Avocados are a popular subtropical fruit of high economic importance, and the European Union is the biggest importer of the bulk of the fruit coming from countries such as South Africa, Chile, and Israel. The fruit is highly nutritious, being rich in vitamins A, B, C, minerals, potassium, phosphorus, magnesium, iron, and antioxidants. The biggest challenge is that the fruit is highly susceptible to qualitative and quantitative postharvest losses. Successful maintenance of avocado fruit quality during the supply chain depends on many aspects, including adequate orchard management practices, harvesting practices, packing operations, postharvest treatments, temperature management, transportation and storage conditions, and ripening at destination. Postharvest losses are mostly attributed to flesh softening, decay, physiological disorders, and improper temperature management. Management of the supply chain is solely done to provide the fruit with the most favorable conditions to extend storage life, and retain quality and nutritional attributes of the fruit. The focus of this review is therefore to study the findings that have emanated from research done to retain overall avocado fruit quality and to reduce postharvest losses during the supply chain through the adoption of appropriate and novel postharvest technologies.     

2010年南非世界杯主办城市与赛场漫谈

4年一度的世界杯,总是能吸引全球人的目光。南非世界杯毫无疑问是2010年夏天的最大焦点,全世界的话题都集中在这项超级体育盛事上。本文主要介绍分析2010年南非世界杯的主办城市和主办赛场,并就世界杯赛场氛围及其文化延展进行探讨。