示差脉冲阳极溶出伏安法测定中药川附子痕量铅镉

本文报道了以ＨＮＯ３－ＨＣｌＯ４湿法消化、醋酸盐介质法差脉冲阳极溶出伏安法测定中药川附子中的铅镉。样品中铅镉含量分别在０．２－０．４μｇ．ｇ＾－１、０．０３－０．１６μｇ．ｇ＾－１,回收率９０－１１０％。     

分光光度法测定COD_(Cr)的试验条件选择

用分光光度法测定水中化学需氧量ＣＯＤＣｒ,通过正交试验选择氧化的最佳选择。试验结果表明对ＣＯＤＣｒ值为５０～１０００ｍｇ／Ｌ的水样：氧化剂Ｋ２Ｃｒ２Ｏ７用量为０．２０～０．４０ｍｏｌ／Ｌ,催化剂Ａｇ２ＳＯ４用量为１０ｇ／ＬＨ２ＳＯ４,消解时间１０ｍｉｎ,加热温度１８０℃。用ＣＯＤＣｒ为１３８ｍｇ／Ｌ的质控标样进行验证试验,其绝对误差为０．５～３．０ｍｇ／Ｌ。与标准方法相比用分光光度法测定ＣＯＤＣｒ具有分析误差小,省时、省力,节约药剂的特点。     

简易流动注射仪化学发光法测定水环境中的铵态氮

在０．１Ｍ的碱性条件下，ＮＢＳ（Ｎ—溴代丁二酰亚　胺）在荧光素的增敏作用下氧化氯化铵，产生强的化学发光。基于此本文详细研究了其反应　的特性和影响因素，在优化的实验条件下体系对氯化铵的测定范围为１．０×１０－７～１　．５×１０－５ｇ／ｍＬ，检出限为３．６×１０－８ｇ／ｍＬ，对５．０×１０－６ｇ／ｍＬ氯化铵　进行１１次平行测定，其ＲＳＤ为２．８％。将本法用于环境水样中ＮＨ＋４的分析，并与常规的　方法进行对照，获得了满意的结果。     

纳氏试剂光度法测定废水中氨氮的问题讨论

应用纳氏试剂比色法测定废水中的氨氮时,水样显色后稳定时间短,影响测定结果的准确性,针对这一问题进行了实验研究。实验中对主要影响因素Ｉ－和ＯＨ－的浓度变化进行了条件实验,结果表明选用所配的Ⅲ型纳氏试剂（ＫＩ含量为７．５ｇ）,可获得稳定的有色胶体,也可采用Ⅰ型纳氏试剂（ＫＩ含量为７．０ｇ）、在中和硼酸后再多加２ｍＬＮａＯＨ（１ｍｏｌ／Ｌ）,也可获得稳定的有色胶体。     

铬酐退铜液影响退铜因素的研究及分析

铬酐退铜由于成份简单、退铜速度快、易于操作而为厂家普遍采用。本文着重研究了铬酐退铜液影响退铜效果的主要因素,通过对「ＣｒＯ３」－ｔ以及「Ｃｕ」＾２＋－ｔ曲线的测量找出退铜液的反应规律。实验表明：提高「ＣｒＯ３」、酸浓度均可提高溶液的退铜能力;溶液中「ＳＯ４」＾２－的增加,则加剧铜的溶解;当溶液中的「ＣｒＯ３」＝１２３－１２６ｇ／Ｌ「Ｃｕ」＾２＋＝２２－２７ｇ／ｌ时,退铜液即失效。失效的退铜液靠单纯     

中药川附子痕量砷的测定

本文报道了以ＨＮＯ３ － ＨＣｌＯ４ 混酸消化、Ｈ２ＳＯ４ － ＫＩ－ Ｔｅ（ Ⅳ） 体系极谱法测定中药川附子中的砷。该方法使样品消化过程的砷损失大为减少并简化了分析过程。样品中砷含量在０－２ ～０－６μｇ·ｇ－ １ ,回收率８４ ％ ～１０８ ％ 。     

α/β探测器改进设计

便携式α/β表面污染仪是辐射环境监测领域重要设备,但其探测器存在体积大、工作电压高等缺点。据此,首先采用硫化锌(银)闪烁体和塑料闪烁体组成复合闪烁体以探测α粒子和β粒子,其次采用硅光电倍增管作为光电转换器耦合复合闪烁体构成新型α/β探测器。改进后的探测器封装体积为Φ8.0 cm×3.0 cm,工作电压范围为23_～26 V。     

离子选择电极法测定水和废水中总氰化物

本文在查阅国内外文献的基础上，对氰化物测定中的前处理方法和干扰消除进行了简要综述。同时对氰离子选择电极法测定氰化物进行了研究，测定的ｐＨ应控制为１２－１３，检测下限为０．０３ｍｇ／ｌ。并用离子交换的方法分离阳离子，以ＰｂＣＯ３为沉淀剂分离Ｓ＾２－后，对废水样进行分析，效果良好。     

利用煤吸附处理含铬废水及生活污水的试验研究

本文研究了四川白皎无烟煤用于生活污水、含铬废水和乐果生产废水的处理。在静态条件下,煤对生活污水中的ＣＯＤ去除率为１２％;对乐果生产废水的脱色率大于６３８％;在含铬工业废水在浓度为３５２６×１０－５ｍｏｌ·ｄｍ－３时Ｃｒ（ＶＩ）的去除率为９０％左右。考察了固液比、温度、浓度和酸度等对煤吸附Ｃｒ（ＶＩ）的影响,并发现吸附量ｑ与时间ｔ之间遵从如下的定量关系：ｑ＝４７６８５（１＋２１２５６ｔ）－１或ｑ＝２１３５１［１－ｅｘｐ（－０５０１６ｔ）］０３８３８     

双流区域地下水污染现状及评价

本文在双流区域地下水污染调查基础之上，选用了主要反映工业生活污染的综合指标ＣＯＤ、ＢＯＤ５和反映农业污染程度的ＮＨ３－Ｎ，ＮＯ３－Ｎ，ＮＯ２－Ｎ作为评价因子，研究了双流地下水污染现状，采用了综合指数法和点群分析法分类并评价了区域地下水污染对饮用水源地的影响程度。     

CALCIUM CARBONATE PRECIPITATION AND TURBIDITY MEASUREMENTS IN OTISCO LAKE,NEW YORK1

ABSTRACT: Calcium carbonate precipitate, known as “whiting,” forms in a large number of hard water lakes and reservoirs, and thus contributes to turbidity measurements in these systems. Here we document the occurrence of “whitings,” and the associated impact on turbidity, in Otisco Lake, New York. A simple, potentially broadly applicable, technique, measurement of turbidity before and after acidification, successfully quantified this component of turbidity in the lake. Calcium carbonate represented 32 percent of the turbidity in the upper waters of Otisco Lake for a three-month period, and at times was as much as 70 percent. Routine monitoring of this component of turbidity in raw water sources, where it is significant, should provide insight into water quality management and treatment plant operations.     

钢铁企业废水污染物形态分析及混凝深度处理试验研究

利用过滤试验与粒径分布试验分析了钢铁工业达标外排废水的各类污染物特征,结合正交试验对混凝处理效果及混凝工艺中各主要影响因素的影响情况进行研究。结果表明,废水中颗粒物主要以粗分散胶体和悬浮态物质为主,PAC／PAM联用对钢铁废水具有较好的处理效果,可有效降低主要影响废水回用的铁锰类污染物,还去除了大部分的有机物及磷类等污染物,各项出水水质指标均达到《城市污水再生利用工业用水水质》（GB／T19923—2005）所规定的循环冷却水回用水质标准。     

Instantaneous char reaction of biomass particles in a hot gas flow with fluctuating temperature

Char reaction is an important stage of the combustion processes of biomass particles. It dominates the burnout of biomass particles. The instantaneous char reaction processes of biomass particles in a hot gas with temperature fluctuation are studied. Two types of biomass fuels, i.e. pine and thistle, are chosen for the present investigation. The instantaneous mass variations of biomass particles with initial diameters of 100, 200, and 300 μm are calculated under different conditions. The gas temperature fluctuation leads to faster mass loss for both pine and thistle particles. The char reaction of biomass particles is further enhanced by increase in the fluctuation amplitude of gas temperature.     

不同粒径土壤中重金属的分布规律

本文选择提钒炼钢厂内部分土壤为研究对象,测定了重金属元素（镉、铜、铬、铅、锌）的含量,并与样品粒度大小的关系进行了探讨,结果表明金属（铜、铬、铅、锌、镉）的浓度最大值出现在粒径较小（100目或160目）的样品中,同时将测定结果与土壤环境质量标准比较,结果表明镉、锌存在污染,其余元素均未超标。     

VARIABILITY OF BOTTOM SEDIMENT CHARACTERISTICS OF THE CONTINENTAL UNITED STATES1

ABSTRACT: Sediment characteristics of samples from physiographic provinces of the continental United States were examined to determine variability within and among physiographic provinces and to compare characteristics of freshwater and saltwater sediments. Organic carbon, particle size distribution, particle surface area, cation exchange capacity, redox potential, and percent solids were examined for a variety of lotic and lentic freshwater sediment samples and nearshore estuarine and marine samples from the continental United States. Analysis of variance indicated significant differences (p < 0.05) within and among physiographic provinces for both freshwater and saltwater sediment samples. Sediment characteristics within physiographic provinces were as variable as characteristics among provinces. Freshwater sediment characteristics were not significantly different (p < 0.05) from saltwater sediment characteristics. Saltwater sediment characteristics were observed to be more strongly correlated with each other than were freshwater sediment characteristics. Based on the variability of sediment samples examined in this study, a specific site may require 50 or more replicate samples to be adequately or accurately represented.     

铅蓄电池厂铅污染土壤清洗剂的筛选及清洗结果研究

为探索不同清洗剂对铅蓄电池厂区内铅污染土壤的去除效果及铅在不同粒径土壤清洗过程中的行为,本研究通过设定清洗剂的浓度梯度,对土样粒径分级、设定清洗时间等方法进行研究。结果显示EDTA和EDDS对铅具有最佳去除率(B点土107.19%和96.49%);盐酸对A点土最佳铅去除率为49.57%,B点、C点土在99.03%和89.93%;柠檬酸对3点位土的铅去除率最大为39.51%;鼠李糖脂对3份土铅去除率均低于10%。EDTA和EDDS在高浓度铅的去除中表现优势;柠檬酸适合去除中低浓度铅;盐酸的使用需考虑土壤本身情况。粗沙粒和细沙粒中的铅去除率高,粉粘粒的铅去除率低;最佳清洗时长为240min。此外,土壤本身理化性质对清洗剂效果的发挥有影响,清洗剂浓度过高可能降低清洗效率。该研究可为铅污染土壤清洗技术提供科学依据。     

TGA analysis of tobacco rob pyrolysis and release characteristics of noncondensable gas in a fixed-bed reactor

In this study, the size of tobacco rob (TR) particle was considered as a major factor in determining the mass loss in thermogravimetric analysis (TGA) and product yield and composition at different reactor temperatures in the fixed-bed reactor. The TGA results showed that the conversion rate increased and the activation energy (ranged from 53.29 to 58.25 kJ/mol) decreased with a decrease in particle size. The experiments demonstrated that fuel gas yield (from 0.76 to 0.82 Nm³/kg at 900 °C) increased with a decrease in particle size while char and tar yield decreased. Smaller particle sizes resulted in higher H₂ (25.68%) and CO (27.36%) contents. Minimizing the size of raw materials is an alternative method to improve the gas quality of TR pyrolysis. The increase of gas yield was attributed to the decomposition of char and tar vapor as temperature increased.     

紫外分光光度测定总氮的影响因素探讨

本文介绍了测定总氮过程中,不同消解方法、碱性过硫酸钾的稳定时间、悬浮物粒径对总氮测定的影响。实验表明:碱性过硫酸钾避光在冰箱中至少可保存一个月,悬浮物粒径对总氮的测定无影响,消解总氮时,可在压力锅加热到120℃开始计时,恒温消解30分钟,自然冷却。     

激光散射技术对絮凝剂分子性能的研究

介绍以激光散射技术对絮凝剂进行的研究。利用激光散射技术实现了对絮凝剂胶体分子粒径、形态结构和粒径分布的精确测量,从而对评价该絮凝剂的沉降性能及有关性能的改进提高起指导作用。     

舟山潮差带海相沉积物的物理和化学特征

为舟山潮差带海相沉积物固结机理的深入研究提供物质基础,采用激光粒度仪分析了海相沉积物的粒度组成,并测试了海相沉积物的化学元素、化合物种类及其相对含量,还使用X-射线衍射技术分析了海相沉物的矿物组成。结果表明:海相沉积物含水率高、初始孔隙比大、呈流塑状,为低液限粉质黏土;活性指数为12.4,属于活动黏性土,矿物的亲水性较好;全盐含量高达9~11.2 g/kg,阳离子交换能力不强,有机质含量(5.82~12.7 g/kg)较高;pH 值为7.35~8.36,呈弱碱性,加上孔隙水中K+ ,Na+ ,Ca2+ ,Mg2+ 的存在,使得高岭石常不稳定,有向伊利石、蒙脱石或绿泥石转化的趋势。