管井降水在某工程中的应用

介绍了某工程的4次降水情况,并对其中2次从理论上进行了分析。     

带热水供应的家用空调器的探讨

针对余热回收技术在国内外的研究和应用状况，分析了夏季家用空调器和热水器运行存在的弊端，提出了将两者合二为一的新系统，并分析了该系统的意义。详细阐述了新设备运行的原理及三种工作模式，以及与常规系统比较所具备的特点。同时，本文对于该系统的今后应用，提出了几个应注意的问题。     

Feeding the global city: urban transformation and urban food supply chain in 21st-century Istanbul

ABSTRACT

This article focuses on the effects of urban transformation on the urban food supply chain in 21st century Istanbul. The article begins with a discussion on the particularities of the urban transformation that has shaped the city since the 1980s, emphasizing tendencies that are relevant to food consumption and supply patterns and practices. Next, 6 categories of fresh fruits and vegetables (FFVs), provisioning agents (mixed/foreign-capital supermarkets, domestic-capital supermarkets, bazaars, local suppliers, and urban and semi-urban/peripheral farmers, internet or store-based alternative food networks) are analyzed in terms of their perception of urban transformation and various challenges it poses. The article concludes with an assessment of the changes in the city’s food supply chain in light of provisioning agents’ responses to the urban transformation as a force that either enables them compete more successfully and expand their operations or pushes them to contract or even leave the provisioning sector completely.     

初始静孔隙水压力对砂土静动力剪切特性影响的试验研究

选取福建标准砂和滹沱河细砂,利用空心圆柱扭剪仪开展了一系列不同初始静孔隙水压力条件下的不排水循环扭剪试验和单调扭剪试验,着重探讨初始静孔隙水压力对超静孔隙水压力发展及其不排水抗剪强度的影响。试验结果表明:初始静孔隙水压力对超静孔隙水压力的发展产生显著的影响,从而影响砂土的静动力剪切特性。具体地,在不排水循环剪切过程中,初始静孔隙水压力越大,其超静孔隙水压力发展和变形发展越快;在不排水单调剪切过程中,初始静孔隙水压力越大,在砂土剪胀阶段产生负超静孔隙水压力越大,从而使砂土的强度显著提高。基于试验结果,初步探讨了初始静孔隙水压力对超静孔隙水压力及静动力剪切特性的影响机理。研究表明,研究地下水位以下土体(准饱和土)静动力剪切特性尤其是研究液化问题时,应充分考虑初始静孔隙水压力对砂土抗液化强度的影响,室内试验应根据砂土所处的地下水位深度来决定初始静孔隙水压力(反压)的大小。     

Evaluation and improvement of total organic bromine analysis with respect to reductive property of activated carbon

A collective parameter and a toxicity indicator for all the halogenated organic disinfection byproducts in a water sample is total organic halogen (TOX), which can be differentiated as total organic chlorine (TOCl), total organic bromine (TOBr) and total organic iodine. The TOX method involves concentration of organic halogens from water by adsorption onto activated carbon (AC). A previous study showed that a portion of TOCl can be reduced to chloride during the adsorption procedure, which can be minimized by ozonation of the AC. In this study, a portion of TOBr was sometimes found to be reduced by AC to bromide, and the reduction was generally less than that of corresponding TOCl. The results suggested that around 10% of brominated Suwannee River fulvic acid was reduced to bromide. However, some brominated amino compounds (especially glycylglycine, phenylalanine, and cytosine) were found to be more reactive with the AC. For the iodinated compounds studied, the reduction to iodide was not significant. The method for the TOBr measurement was improved by using ozonated AC when reduction occurred on the original AC. The improved method was also evaluated on treated wastewater and swimming pool water samples.     

城市传统文化景观空间结构保护

以山地为主的地理和气候条件孕育了我国深厚的山水文化,从原始的聚落到封建城邑都无不反映着对山水格局的精微关注,形成了独特的城市文化景观和生态体系。随着现代城市大规模的快速发展,这一体系正在面临严重的挑战,它们的保护成为中国传统城市、聚落特有的历史任务。     

大过冷度逆流式过冷器换热特性研究

阐述了大过冷度制冷——高温水蓄冷空调系统原理,对该系统中的关键设备过冷器进行了选型和计算。在液——液换热型板式换热器传热特性无资料的情况下,根据板式蒸发器的传热特性和管式液——液热交换换热器与管式蒸发器的传热系数的比值来估算板式过冷器的传热系数或传热单元数。实验证明,这种设计方法是成功的。     

集中空调冷却水变流量问题辨析

指出集中空调冷却水系统为开式系统，一般不适用功率三次方定律，静压头应为冷却塔塔体扬程，并提出了冷却水泵变速时轴功率的计算公式；明确变流量的节能效果与控制方式密切相关，即使机组处于满负荷状态，但只要是在非设计工况，采用冷凝温度控制法，也可能实现变流量节能；指出制定多台冷水机组部分负荷性能指标的意义。     

相变微囊复合建材制备及储放热研究

通过采用微乳化技术,将水分散于常温相变储能石蜡中;应用膜孔法,以海藻酸钠包封常温相变石蜡,制得储能微囊;将微囊与石膏基体复合后,制备得到储能建筑材料.研究发现:储能微囊为球形,其粒度分布范围窄;相变含水石蜡微囊储能建筑材料的储能密度得到显著提高,在低于常温相变石蜡固-液相变温度下,其导热系数减小,储/放热时间明显延长,对环境温度的变化响应滞后时间加大,维持恒定温度的时间得到较大延长.     

Modeling and monitoring of long-term acidification in an upland catchment of the Western Ore Mountains,SE Germany

Modeling and monitoring of acidification patterns in a limed forest catchment in the Ore Mountains, SE Germany are presented. A lumped-parameter model, MAGIC, satisfactorily reproduced the main parameters of stream water chemistry. Despite repeated whole-catchment liming, between 1993 and 1999 stream water pH increased from 4.3 to only 4.6, while calcium concentrations declined slightly. Stream water sulfate concentration declined from 687 to 396 microeq l(-1), and the pronounced effect of deposition decline during the 1990s was probably more important than liming.