帕尔玛路面在长江南岸堤顶防汛道路中的应用

帕尔玛路面是近年来兴起的一种新型路面结构型式,具有强度高、抗渗性好、裂缝后可自愈的特点,可省去普通泥结石层下的手摆块石基层,因而具有施工速度快、造价亦较低的优点。文章介绍了这种新型路面在安徽省长江南岸堤防加固防汛道路中的应用情况,对使用过程中出现的一些问题进行了分析,提出了改进的建议。     

帕尔玛基层技术在拉萨林春公路的应用

从帕尔玛固化酶工作原理到帕尔玛基层应用于青藏高原公路建设的可行性作了系统论述，并结合拉萨市林春公路施工的实践分析，总结了帕尔玛基层技术在青藏高原应用的成功案例，最后得出帕尔玛基层技术在拉萨可以成功应用的结论。     

帕尔玛筑路原理及公路施工技术

介绍了帕尔玛筑路技术的原理，从基底、配料、拌和、摊铺、压实、面层、养护等环节阐明了该技术的施工方法，指出用帕尔玛法筑路质量高、使用期长，利于环保、节省投资。     

Woermann广场与塔楼

<正>Woermann之所以会成为拉斯帕尔玛斯城最热卖的地产,80%的原因来自于他的外表。虽然只有60米高,跟世界其他高楼相比乏善可陈,但是在当地堪称建筑地标。它的外观足够亮丽,与面前的碧海蓝天,身后的棕色山头,甚至街道两旁一字排开的棕榈树,在色调上都不谋而合。     

多孔混凝土路面研究综述

对多孔混凝土进行了介绍,指出多孔混凝土路面是透水路面、低噪声路面、更为安全的路面,重点研究了多孔混凝土路面的组成结构、强度、透水系数及耐久性,归纳了多孔混凝土路面的主要优点,从而促进多孔混凝土路面的研究应用。     

工程机械英语

路面机械是用于修建公路、城市道路的路面和飞机场道面等的一类机械,分为土路面施工机械、碎石路面施工机械、沥青混凝土路面施工机械和水泥混凝土路面铺筑机械4类。土路面施工机械主要是稳定土搅拌机械,碎石路面施工机械主     

公路路面检测技术综述

针对我国公路发展现状及存在的问题,指出公路路面检测技术的重要性。介绍了路面平整度、路面承载能力、路面抗滑性能、路面厚度以及路面破损检测技术,探讨了我国公路路面的各种检测技术、检测方法与检测仪器设备的优缺点,在此基础上提出了公路路面检测技术的发展趋势。     

复合式路面在桥梁间短路基中的应用

结合云南省大丽高速公路路面实际情况,讲述了复合式路面在桥梁问短路基中的应用,通过复合式路面与普通沥青混凝土路面的对比分析,得出复合式路面在提高路基与桥梁整体性、解决桥头跳车、施工便捷性、节约资源、提高路面行车舒适性及路面长效性等方面的优点。     

对不同类型沥青混凝土路面渗水系数试验方法的探讨

对密集配沥青混合料路面、SMA沥青混合料路面、透水沥青混凝土路面3种类型路面渗水系数试验方法和结果进行了分析,得出规范中采用的路面渗水仪对密集配沥青混合料路面、SMA沥青混合料路面的渗水系数检测是适用的,对透水沥青混凝土路面是不适用的。通过对原路面渗水仪进行改造,延长了试验过程时间,并通过对比试验验证了改造后的路面渗水仪试验数据的可靠性。     

谈道路路面材料发展趋势

概述了传统路面材料及新型路面材料的类型、特点及其适用区域,着重介绍了道路路面材料研究的新趋势,即功能型路面材料和环保型路面材料,以满足对新型道路路面更舒适、更安全、更环保的要求。     

派酶掺入三合土对土体抗压强度影响的探讨

利用一种生物酶类土壤固化剂——派酶,以适当比例掺入两种配合比的压实三合土中,测得其28d无侧限抗压强度均比未掺派酶时有所提高.在石灰掺量较高的情况下,掺派酶后三合土土体的28d无侧限抗压强度仍比未掺派酶时有较大幅度的提高,说明在具有抑制和杀灭细菌的较高碱度环境下,派酶对土体结构的增强作用不是因为其单纯地促进土壤中存在的各种菌类活动所引起的.掺派酶三合土的X射线衍射分析图谱横坐标28°附近位置出现明显超过未掺派酶三合土的强峰,不能排除派酶的掺入会促进土体固化过程中某种晶型变化产生的可能性.SEM显微结构形貌图片显示掺派酶三合土试件的微结构比未掺派酶试件更紧凑、密实.基于分形几何理论研究发现,派酶的掺入促进了三合土土体中细小孔隙增多,大孔隙减少,有利于土体中颗粒间相互作用力的增强.     

城外造景：清末广州景园营造与岭南 园林的近代转型

清末广州中西交汇,景园营造新旧共存互动,推 动岭南园林的近代转型。其中,在繁荣的中西贸易和文化交 流,以及书院文化、士绅文化等的影响下,清末岭南形成了 以广州为中心、十三行行商为代表、官商士绅竞相造园的特 殊历史时期,其造园数量、规模、意匠等均在该时期达到岭 南古典园林发展的巅峰。这一时期也是岭南园林近代转型的 关键时期。在西方文化和清末洋务运动思想的影响下,广州 开始出现洋务花园、公园、市政绿化,以及校园绿地等新型 园林形式。这些具有公共性质的城市景致与新建私园一道广 泛分布在城墙以外,成为清末广州城市空间拓展与风景体系 形成的重要参与者。由于清末广州城外造景的繁荣,从时间 上开启了岭南园林的近代转型,在空间上使岭南园林的地域 性特征得以形成和辨识,其空间性与时间性界定了清末岭南 园林近代转型的物质及文化维度。梳理了清末广州具有代表 性的景园营造活动,在分析其动力机制的同时,探讨城外造 景之于岭南园林近代转型的意义。     

中国绿道规划建设实践——从提级统筹到制度并轨

绿道在中国经过多年实践发展,在理论内涵、规划选线、综合效益等各方面都已有许多成果支撑.基于可公开获取的一系列文献资料,立足于绿道在中国各省市近20年的具体实践过程,梳理绿道在规划体系中的角色转变、在指标设置中的逐步细化和在管控上的落实方式,总结绿道实践在中国从提级统筹、常态认同到制度并轨3个阶段的发展变化,在展望绿道后...     

Alteration of arsenopyrite in soils under different vegetation covers

The weathering of arsenopyrite (FeAsS) has been monitored in soils using an in situ experimental approach. Arsenopyrite in nylon experimental bags was placed in individual horizons in soils in spruce (litter, horizons A, B, and C), beech (litter, horizons A, B, and C) and unforested (horizons A, B, and C) areas and left in contact with the soil for a period of 1 year. The individual areas on the ridge of the Krušné hory Mts., Czech Republic, had the same lithology, climatic and environmental conditions. Scorodite (FeAsO₄·2H₂O) was identified as a principal secondary mineral of arsenic (As) formed directly on the surface of the arsenopyrite. Scorodite was formed in all the areas in all soil horizons. The amount of scorodite formed decreased in the series beech, spruce and unforested areas. In forested areas, there was a larger amount of scorodite on arsenopyrites exposed in organic horizons (litter, A horizon). The greater rate of arsenopyrite alteration in organic horizons in the beech stand compared to spruce stand is probably a result of faster mineralization of organic material with resulting production of nitrate and better seepage conditions of soil in this area. Speciation of As determined using the sequential extraction technique demonstrated that As was bonded in the soils primarily in the residual fractions prior to the experiment. The As content in the mobile fractions increased in the organic horizon in the forested areas after the experiments.     

化学溶液和干湿循环作用下砂岩抗剪强度劣化试验及化学热力学分析

 为研究化学溶液和干湿循环共同作用下砂岩抗剪强度的劣化机制,在不同pH环境下,通过不同干湿循环次数后的单轴、三轴试验,计算出砂岩的黏聚力和内摩擦角,同时得到其与循环次数的关系式,进而获得砂岩在浸泡环境下抗剪强度随干湿循环次数的变化公式。根据砂岩的组成矿物及其百分含量,得到各种主要组成矿物在中性、碱性、酸性溶液中溶解的化学反应方程式,利用化学热力学的基本原理,确定各主要矿物在中性、碱性、酸性溶液浸泡下能否稳定。为了验证分析的正确性,对浸泡溶液中的部分离子(Ca2+,SiO2,Na+,K+)浓度进行测试。结果表明,酸性环境下,砂岩抗剪强度劣化最为严重,碱性次之,中性最轻。在酸性环境中,对抗剪强度影响较大的胶结物主要组成成分(长石、方解石)的性质不稳定,溶解反应能自发进行,而碱性环境中,对强度影响较小的骨料主要组成成分(石英)的性质不稳定,溶解反应能自发进行。酸性浸泡液中,方解石、钾长石、钠长石溶解出的Ca2+,K+,Na+的浓度明显高于中性和碱性液中Ca2+,Na+,K+的浓度,而碱性溶液中,石英溶解出的SiO2的浓度明显高于中性和酸性液中SiO2的浓度,与热力学分析结果一致。     

Health assessment of artisanal gold miners in Indonesia

Small scale miners use mercury to extract gold from ore in many countries. An environmental and health assessment was performed in Indonesia in two regions, Galangan in Central Kalimantan and Talawaan in Northern Sulawesi. The environmental assessment showed severe mercury contamination of the sediments, and increased mercury levels in local fish. For the health investigation 281 volunteers were recruited and examined by a standardized questionnaire, a neurological examination and neuro-psychological tests. A medical score was used consisting of significant factors of mercury intoxication. Mercury exposed workers showed typical symptoms of mercury intoxication, such as movement disorders (ataxia, tremor, dysdiadochokinesia, etc.). Blood, urine and hair samples were taken from any participant and analyzed for mercury. The mercury concentration in the biomonitors was high, partly extreme high in the working population, increased in the population living in the same habitat and low in the control group. By a standard protocol which includes a combination of threshold values of mercury in the biomonitors and a medical sum score the diagnosis of chronic mercury intoxication was made for highly burdened workers (amalgam smelters) in 55% in Sulawesi and in 62% in Kalimantan. Less exposed mineral processors and the general population in the mining areas were also intoxicated to a high percentage.     

Polycyclic aromatic hydrocarbons (PAHs) in agricultural soil and vegetables from Tianjin

Several types of vegetables were collected from two contaminated sites in Tianjin, China. The bulk soil and the rhizosphere soil samples were also collected from the same plots. Sixteen PAHs in the samples were measured. The total concentrations of PAH16 in the bulk soil from the two sites were 1.08 and 6.25 microg/g, respectively, with similar pattern. The concentrations of PAH16 and individual compounds in the rhizosphere were significantly higher than those in the bulk soil with mean values of 2.25 and 7.82 microg/g for the two sites, respectively. The contents of both total and dissolved organic matter in the rhizosphere were also higher than those in the bulk soil. Almost all PAH compounds studied were detected in both roots and aerial parts of the vegetables studied. Abundance of higher molecular weight PAHs in vegetable, however, was lower than that in soil. Concentrations of PAH16 in vegetable were higher than those reported in the literature for other areas. It appears that agricultural soils and vegetables in Tianjin, especially those from the site located immediately next to an urban district and irrigated with wastewater for several decades, are severely contaminated by PAHs. Among the eight types of vegetable studied, the highest concentration of PAHs was found in cauliflower. By average, the concentration of PAH16 in the aerial part of vegetables was 6.5 times higher as that in vegetable root, suggesting that foliar uptake is the primary transfer pathway of PAHs from environment to vegetables.     

Cell phones for the spirits: ancestor worship and ritual economies in vietnam and its diasporas

Religion has been thriving in the Socialist Republic of Vietnam since ??i m?i, the onset of market reforms in the late 1980s. Votive paper offerings, part of spiritual and economic well-being, play a crucial role in performing religious practices in the socialist country as well as among diasporic Vietnamese. In urban Hanoi, material objects made from paper are traded in marketplaces and later burned in the streets, in temples and pagodas, in private yards and other places on special occasions in order to be transmitted to the ancestors. In the past few years, the range of votive paper offerings produced, traded, and sent to the deceased has expanded to include new forms and references to new media. Drawing on recent debates in the role of media in religion and in particular on technologies of mediation, I focus on the use of votive paper offerings in the sociocultural context of the Vietnamese spirit world. I explore how new media and media technologies are embedded in multilayered processes of mediation in Vietnam and its diasporas. Taking religious practices of burning votive paper offerings as an ethnographic example, this essay aims to contribute to ongoing debates on popular religion and the sacred life of material goods in late socialist Vietnam, on its transnational ties, and on the entanglements between religion, media and materiality.     

Levels, fluxes and time trends of persistent organic pollutants in Lake Thun, Switzerland: Combining trace analysis and multimedia modeling

Levels, mass fluxes, and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Lake Thun, a peri-Alpine lake, are investigated. We present measurements of PBDEs and PCBs in air, lake water, lake sediment, and tributary water. These measurements are combined with a multimedia fate model, based on site-specific environmental parameters from the lake catchment. Measured loadings of PBDEs and PCBs in air and tributaries were used to drive the model. The model satisfactorily reproduces PBDE and PCB congener patterns in water and sediment, but it tends to yield concentrations in water below the measurements and concentrations in sediment exceeding the measurements. A sensitivity analysis reveals that partitioning of PBDEs and PCBs between the aqueous dissolved phase and suspended particulate matter in the water column strongly affects the model results, in particular the concentrations in water and sediment. For lower-brominated PBDEs, approximately 70% and 30% of input into the lake stems from atmospheric deposition and from tributaries, respectively. For heavier PBDEs and all PCBs, rivers appear to deliver the major load (64-92%). Waste water effluents are of minor importance. 50-90% of the total input is buried in the permanent sediment. Sediment burial makes PBDEs and PCBs less available for recycling in the environment, and reduces concentrations in the outflowing river. If use of deca-BDE increases in the future, levels in Lake Thun will follow the same trend. If the use and resulting environmental emissions decrease, concentrations in water will rapidly decline, according to our calculations, while sediment levels will decrease at a considerably slower rate.     

Heterotrophic and mixotrophic growth of Micractinium pusillum Fresenius in the presence of acetate and glucose: effect of light and acetate gradient concentration

The main objective of this study was to determine the importance of secondary mechanism of organic carbon utilization (mixotrophic and heterotrophic modes) in addition to CO2 fixation (photoautotrophic mode) in the green alga, Micractinium pusillum Fresenius (chlorophyta), isolated from a waste stabilization pond. The growth was studied in the presence of acetate and glucose. The incorporation rate of 14C- acetate was measured in the light and in the dark at different concentrations. Finally, in order to underline the role of photosynthesis and respiration processes in the acetate assimilation, the effect of two specific metabolic inhibitors, a specific inhibitor of photosystem II (DCMU) and an uncoupler respiratory (DNP), has been studied. The obtained results showed that M. pusillum grows in the presence of organic substrates, i.e., glucose and acetate, in the light (mixotrophic growth) as well as in the dark (Heterotrophic growth). The growth was much more important in the light than in the dark and more in the presence of glucose than of acetate. In the light, the presence of acetate led to a variation of growth parameters mumax, iotaopt, and beta. The effect of acetate gradient on the growth of the microalga was severe as soon as its concentration in the medium was higher. The acetate uptake followed a Michaelis-Menten kinetic in the light as well as in the dark. The capacity of assimilation was slightly higher in the dark. The utilization of DNP and DCMU indicates that acetate incorporation is an active process depending on both anabolic (photosynthesis) and catabolic (respiration) metabolisms, corroborating the model of the Michaelis-Menten kinetic.