西安市自来水中铁锰来源的分析

分析了影响西安市供水系统铁、锰含量的主要因素,包括水文地质条件、气候条件、污染程度及水质稳定性等,指出其主要来源,并提出通过加强水源保护等措施来控制水中的铁锰含量.     

对某商品混凝土搅拌站强度检测结果异常值的分析

对异常值的深入分析，常常能发现一些很重要的线索，可找出试验上重大误差发生的原因、次数、误差范围等线素。因此我们必须慎重地对待检测中出现的异常值。本文从一起混凝土强度检测的异常值中发现是由检测中的差错引起的，同时发现此差错是检测中的普遍现象，望大家对此引起重视。     

2001—2012年北京市API变化趋势分析

随着北京雾霾天气的频繁发生,空气质量状况日益受到关注。运用时间序列分析描述方法,描述2001—2012年间北京市的空气污染指数(air pollution index,API)随时间的变化趋势及与降雨量、风速、气温、湿度等气象因素的相关性。结果表明API指数整体呈下降趋势;春季和冬季的月API指数最高,夏季最低,存在明显的季节性,3、4月的月API指数较高,7、8月的月API指数最低;首要污染物中SO2所占的比例在减少,可吸入颗粒物的比例在升高;API指数与降雨量存在负相关关系,与风速、气温、湿度等存在正相关的关系。     

饮用水中铁检测能力验证中的质量控制

目的介绍饮用水中铁检测能力验证中的质量控制。方法运用火焰原子吸收分光光度法测定饮用水中铁能力验证考核样品,从仪器设备、实验人员、样品的保存及使用、仪器参数的优化、标准溶液的核查、预实验、样品分析和数据处理等方面对实验进行了质量控制。结果饮用水中铁检测能力验证结果均为满意。结论饮用水中铁检测能力活动中采取的质量控制措施能够有效保证检测结果的准确性。     

氧弹燃烧灰化法测定聚丙烯中铁的含量

用氧弹燃烧灰化法对有机物中铁的含量进行测定,方法操作简便、快速,实验过程无污染,测定结果可靠。     

严格控制玻璃中铁的含量提高器皿玻璃的白度

随着人民生活水平的提高,人们对高白度器皿玻璃的要求越来越高。我厂无色器皿玻璃基本上有两种,一种是钠钙玻璃,另一种是铅晶质玻璃。所谓高白度的器皿玻璃必须是在正常光线下目视感觉看不出玻璃有颜色,玻璃透明度好、亮度高,铅晶质玻璃还需要有一定指标的氧化铅含量和较高的折射率。要想达到用户要求的高白度器皿玻璃,必须严格控制玻璃中铁的含量。     

介绍一种快速测定铁矿石中铁含量的方法

介绍一种快速测定铁矿石中铁含量的方法赵洪东卢加珠（平邑万寿宫水泥有限公司）窦兆祥（山东省水泥质检站）１前言水泥企业控制进厂铁矿石的质量，常采用全分析的方法测定含铁量，虽然十分准确，能有效地控制进厂铁矿石的质量，但这种方法比较费时，大半天才能出结果，不...     

火焰原子吸收法测锂云母中铁的含量

本文运用空气-乙炔火焰原子吸收分光光度计对锂云母中铁进行测定,并介绍了铁的最佳测定条件,该方法具有很好的灵敏度、较快的分析速度。     

我国固定资产投资增长率预测分析

固定资产投资作为投资的重要组成部分,是社会经济发展的一个重要动力,是社会固定资产再生产的主要手段。因此,预测我国固定资产投资增长率对于促进我国经济增长具有重要意义。从动态分析的角度出发,本文以我国1981—2013年的全社会固定资产投资增长率为一个时间序列,运用Eviews6.0软件对其进行分析。由分析结果可知,ARMA(4,3)模型提供了较为准确的模拟结果,可用其来预测我国固定资产投资未来增长率,为我国全社会固定资产投资决策提供可靠的参考依据。     

基于监测数据的马坪滑坡稳定性分析

滑坡位移变形的产生及演变,对于滑坡安全稳定性的评价至关重要。本文以德化县马坪滑坡为例,利用位移监测数据,并结时间序列模型分析滑坡体的位移变化,在此基础上结合降雨、地下水等影响因素分析对今后滑坡的稳定性进行了预测。结果表明基于位移监测数据的时间序列模型具有较高精度,对了解边坡位移的发展趋势以及研究边坡的动态稳定性是有效可行的。     

Subsurface iron and arsenic removal for shallow tube well drinking water supply in rural Bangladesh

Subsurface iron and arsenic removal has the potential to be a cost-effective technology to provide safe drinking water in rural decentralized applications, using existing shallow tube wells. A community-scale test facility in Bangladesh was constructed for injection of aerated water (∼1 m³) into an anoxic aquifer with elevated iron (0.27 mmol L⁻¹) and arsenic (0.27 μmol L⁻¹) concentrations. The injection (oxidation) and abstraction (adsorption) cycles were monitored at the test facility and simultaneously simulated in the laboratory with anoxic column experiments.Dimensionless retardation factors (R) were determined to represent the delayed arrival of iron or arsenic in the well compared to the original groundwater. At the test facility the iron removal efficacies increased after every injection-abstraction cycle, with retardation factors (R_Fe) up to 17. These high removal efficacies could not be explained by the theory of adsorptive-catalytic oxidation, and therefore other ((a)biotic or transport) processes have contributed to the system’s efficacy. This finding was confirmed in the anoxic column experiments, since the mechanism of adsorptive-catalytic oxidation dominated in the columns and iron removal efficacies did not increase with every cycle (stable at R_Fe = ∼8). R_As did not increase after multiple cycles, it remained stable around 2, illustrating that the process which is responsible for the effective iron removal did not promote the co-removal of arsenic. The columns showed that subsurface arsenic removal was an adsorptive process and only the freshly oxidized adsorbed iron was available for the co-adsorption of arsenic. This indicates that arsenic adsorption during subsurface treatment is controlled by the amount of adsorbed iron that is oxidized, and not by the amount of removed iron. For operational purposes this is an important finding, since apparently the oxygen concentration of the injection water does not control the subsurface arsenic removal, but rather the injection volume. Additionally, no relation has been observed in this study between the amount of removed arsenic at different molar Fe:As ratios (28, 63, and 103) of the groundwater. It is proposed that the removal of arsenic was limited by the presence of other anions, such as phosphate, competing for the same adsorption sites.     

原水铁锰含量对细菌除铁除锰效能的影响

将从水厂成熟锰砂中分离出来的细菌进行驯化和增殖培养,通过改变原水中铁锰含量来改变细菌生长环境,考察了不同条件下混合细菌对铁锰的去除效果.结果表明:在有Fe2+存在的情况下,铁锰氧化细菌维持着正常的活性,对铁锰始终具有高效而稳定的去除能力;Fe2+的存在与否也影响着Mn2+的氧化速率;原水中锰的存在对细菌除铁影响较小.     

Biological iron oxidation by Gallionella spp. in drinking water production under fully aerated conditions

Iron oxidation under neutral conditions (pH 6.5-8) may be a homo- or heterogeneous chemically- or a biologically-mediated process. The chemical oxidation is supposed to outpace the biological process under slightly alkaline conditions (pH 7-8). The iron oxidation kinetics and growth of Gallionella spp. - obligatory chemolithotrophic iron oxidizers - were assessed in natural, organic carbon-containing water, in continuous lab-scale reactors and full-scale groundwater trickling filters in the Netherlands. From Gallionella cell numbers determined by qPCR, balances were made for all systems. The homogeneous chemical iron oxidation occurred in accordance with the literature, but was retarded by a low water temperature (13 °C). The contribution of the heterogeneous chemical oxidation was, despite the presence of freshly formed iron oxyhydroxides, much lower than in previous studies in ultrapure water. This could be caused by the adsorption of natural organic matter (NOM) on the iron oxide surfaces. In the oxygen-saturated natural water with a pH ranging from 6.5 to 7.7, Gallionella spp. grew uninhibited and biological iron oxidation was an important, and probably the dominant, process. Gallionella growth was not even inhibited in a full-scale filter after plate aeration. From this we conclude that Gallionella spp. can grow under neutral pH and fully aerated conditions when the chemical iron oxidation is retarded by low water temperature and inhibition of the autocatalytic iron oxidation.     

The development of a combined water demandprediction system

This paper introduces a system designed to improve the accuracy of short term water demand forecasts by combining a proven mathematical prediction model with a knowledge base of information relating to non-cyclic abnormal demand occurrences. In part one of the paper, a prototype system is described that comprises a mathematical prediction module and a simplified knowledge base of FORTRAN rules. The results derived from the testing of the prototype show that the methodology is capable of providing significant improvements in prediction accuracy when the normal cyclic demand pattern is disrupted. Part two of the paper describes the steps taken towards implementing the elements that make up a full combined forecasting system in the light of the knowledge gained from building and testing the prototype.     

对村庄水系统规划编制内容的探讨

在分析了我国农村水系现状问题的基础上,构建了村庄水系统规划的编制内容,包括水系治理规划、河道保护规划、给水设施规划和排水设施规划,并对四个方面的要点、标准进行了详细阐述,以期指导村庄水系统工程规划建设。     

Morphological and physicochemical characteristics of iron corrosion scales formed under different water source histories in a drinking water distribution system

The corrosion scales on iron pipes could have great impact on the water quality in drinking water distribution systems (DWDS). Unstable and less protective corrosion scale is one of the main factors causing “discolored water” issues when quality of water entering into distribution system changed significantly. The morphological and physicochemical characteristics of corrosion scales formed under different source water histories in duration of about two decades were systematically investigated in this work. Thick corrosion scales or densely distributed corrosion tubercles were mostly found in pipes transporting surface water, but thin corrosion scales and hollow tubercles were mostly discovered in pipes transporting groundwater. Magnetite and goethite were main constituents of iron corrosion products, but the mass ratio of magnetite/goethite (M/G) was significantly different depending on the corrosion scale structure and water source conditions. Thick corrosion scales and hard shell of tubercles had much higher M/G ratio (>1.0), while the thin corrosion scales had no magnetite detected or with much lower M/G ratio. The M/G ratio could be used to identify the characteristics and evaluate the performances of corrosion scales formed under different water conditions. Compared with the pipes transporting ground water, the pipes transporting surface water were more seriously corroded and could be in a relatively more active corrosion status all the time, which was implicated by relatively higher siderite, green rust and total iron contents in their corrosion scales. Higher content of unstable ferric components such as γ-FeOOH, β-FeOOH and amorphous iron oxide existed in corrosion scales of pipes receiving groundwater which was less corroded. Corrosion scales on groundwater pipes with low magnetite content had higher surface area and thus possibly higher sorption capacity. The primary trace inorganic elements in corrosion products were Br and heavy metals. Corrosion products obtained from pipes transporting groundwater had higher levels of Br, Ti, Ba, Cu, Sr, V, Cr, La, Pb and As.     

钢铁中硅含量测定方法的研究

采用还原型硅钼酸盐光度法对钢铁中硅含量进行了实验测定,根据测定原理,介绍了试料分解和试液制备的方法,并对最低检出限、精密度、准确度进行了分析,指出实验测定值均在标准样品保证值范围内。     

原子荧光法测定生活饮用水中砷的含量

介绍了原子荧光法的原理,论述了采用原子荧光法测定生活饮用水中的砷含量的实验主要仪器、试剂及仪器的工作参数,并对主要的实验步骤进行了详细分析,提出了一些实验注意事项,以供参考。     

管道直饮水系统设计初论

对管道直饮水处理工艺的设置、设计秒流量公式的选用进行了探讨，介绍了用概率法计算直饮水设计秒流量的方法，并与规范中的方法作了比较，说明该方法的合理性和简便性。     

Speciation and distribution of vanadium in drinking water iron pipe corrosion by-products

Vanadium (V) when ingested from drinking water in high concentrations (> 15 μg L^− 1) is a potential health risk and is on track to becoming a regulated contaminant. High concentrations of V have been documented in lead corrosion by-products as Pb₅(V⁵⁺O₄)₃Cl (vanadinite) which, in natural deposits is associated with iron oxides/oxyhydroxides, phases common in iron pipe corrosion by-products. The extent of potential reservoirs of V in iron corrosion by-products, its speciation, and mechanism of inclusion however are unknown. The aim of this study is to assess these parameters in iron corrosion by-products, implementing synchrotron-based μ-XRF mapping and μ-XANES along with traditional physiochemical characterization. The morphologies, mineralogies, and chemistry of the samples studied are superficially similar to typical iron corrosion by-products. However, we found V present as discrete grains of Pb₅(V⁵⁺O₄)₃Cl likely embedded in the surface regions of the iron corrosion by-products. Concentrations of V observed in bulk XRF analysis ranged from 35 to 899 mg kg^− 1. We calculate that even in pipes with iron corrosion by-products with low V concentration, 100 mg kg^− 1, as little as 0.0027% of a 0.1-cm thick X 100-cm long section of that corrosion by-product needs to be disturbed to increase V concentrations in the drinking water at the tap to levels well above the 15 μg L^− 1 notification level set by the State of California and could adversely impact human health. In addition, it is likely that large reservoirs of V are associated with iron corrosion by-products in unlined cast iron mains and service branches in numerous drinking water distribution systems.