双波长K系数方程法同时测定水样中的砷和磷酸盐

双波长K系数方程法同时测定水样中的砷和磷酸盐，是指选定两个测定波长λ1、λ2，将磷酸盐、砷在λ2处的吸光度转化为λ1处的吸光度，列出一个二元一次方程组，解得磷酸盐、砷在λ1处的吸光度，进而求得水样中的磷酸盐、砷含量。     

阻抑光度法测定痕量乙醇的研究

文章研究了在稀硫酸介质中,乙醇阻抑高碘酸钾氧化中性红褪色反应的各种反应条件,建立了阻抑光度法测定痕量乙醇的新方法。讨论了体系酸度、试剂浓度、反应温度、反应时间、干扰离子等因素对反应体系的影响。选择530nm作为测定波长,确定了阻抑反应的最佳条件。在所选择的试验条件下,方法的线性范围为1.0~7.0μg/25mL,检测限为4×10~(-6)g/L。表观摩尔吸光系数ε=3.68×10~4L/mol·cm。对该方法进行了精密度测定,其相对标准偏差RSD5%。该方法用于水样中痕量乙醇含量的测定,并进行了加标回收试验,平均回收率为98.6%~98.7%。     

系统聚类-Elman神经网络同时测定废水中的铁、镍、铜

为建立能同时测定工业废水中铁、镍、铜含量的化学方法,本文提出铁、镍、铜与5-Br-PADAP及OP在pH 3.5缓冲液中生成稳定的配位化合物,在一定的波长范围内进行同时测定。将系统聚类方法应用于此测定体系的计算,使光谱重叠及光度分析计算中的校正模型的优化问题得到有效的解决。通过最佳化确定了Elman神经网络的结构和参数,将Elman神经网络应用于模拟废水以及实际废水中Fe（Ⅲ）、Ni（Ⅱ）、Cu（Ⅱ）的测定,回收率分别在97%～102.8%和97.4%～102.6%之间,结果满意。     

重铬酸钾褪色法和硫酸铬显色法直接测定COD_Cr

建立了重铬酸钾褪色法和硫酸铬显色法直接比色测定CODcr的方法，重铬酸钾褪色法测定范围10-700mg／L，检出限7.0mg／L，三次平行测定CODcr值为417mg／L样品，标准差为2.6mg／L，回收率为96.6％；硫酸铬显色法的测定范围30-1200mg／L，检出限为23.0mg／L，三次平行测定CODcr值为987mg／L，标准差为22.3mg／L，回收率为96.3％，两种方法都优于HJ／T399-2007推荐的方法。     

ICP-AES法测定硅铁中铝磷钙钛铬锰镍铜钡钒钴镁钼含量

本文用ICP—AES内标法进行硅铁中的铝、磷、钙、钛、铬、锰、镍、铜、钡、钒、钴、镁、钼含量测定。研究了溶样方法、测定时溶液的酸度、仪器工作条件、各元素测定波长，测试结果与标准样品推荐值比较，结果令人满意。     

荧光法测定黄瓜中的谷胱甘肽

研究了用荧光分光光度计测定黄瓜中谷胱甘肽的方法。在荧光条件激发波长EX为340nm,发射波长EM为420nm时,其测定回收率为99．55％－99．95％,变异系数为1．24％。     

紫外法测定石油类的标准物质比对分析

对紫外法测定地表水中石油类污染物的三个厂家标准物质的吸收波长、校准曲线、质谱和测定结果进行了对比分析.试验结果表明,不同厂家标准物质的配制成分不同,标准曲线差异大,导致测定结果偏差较大,数据可比性和准确性较差,对石油类监测带来了困扰,建议国家在市售正已烷体系适用于紫外分光光度法测定的有证标准物质的选用上做出明确规定.     

二次电子发射系数在航天器表面充电的应用

二次电子发射现象是电子入射到材料表面并从材料表面激发出次级电子的现象。在航天领域,二次电子发射系数对于评估和预测航天器的表面充电水平具有十分重要的作用。本文对航天器的表面充电机制进行了介绍,结合航天器表面充电平衡方程编写了计算航天器表面充电电位的Matlab程序,使用航天表面材料二次电子发射系数的测量结果通过计算获得了特定环境下某材料的表面充电电位,为评估材料二次电子发射系数对表面充电的影响提供了一个直接的分析工具。     

紫外分光光度法测定水中离子液体浓度

本文提出了一种基于比尔-朗伯定律的使用紫外光谱法测量水中离子液体含量的方法。我们考察了7种常见离子液体的紫外光谱,找出其最大吸收波长,计算了吸光系数。利用不同浓度的标准溶液建立了工作曲线,并测量了模拟水样中离子液体的浓度,加标回收的结果能够满足分析要求。     

哈希快速消解法测定高氯废水CODCr的优化

采用哈希（HACH）20 min快速消解分光光度法,对高氯废水化学需氧量CODCr的快速测定进行了探讨试验.通过多种条件试验探索出简单方便、快速测定高氯废水CODCr的优化方法.该方法采用样品与硫酸汞外部络合预处理,消除氯离子干扰,在165℃的条件下与硫酸-硫酸银及强氧化剂重铬酸钾一起加热消解20 min,冷却至室温后,于420 nm波长下测定剩余Cr6＋的含量,结果与在线分析仪测定结果基本一致,与HJ/T70-2001《高氯废水化学需氧量的测定氯气矫正法》测定结果相比,相对误差为7.28％～9.8％,可以满足该单位生产控制及应急监测的需要.     

烧结烟气中CO对SO2监测的干扰分析

通过承钢烧结机脱硫出口SO2的比对监测,发现在线及手持监测设备正常但监测数据仍比对不合格。进行CO干扰实验,得出CO对采用＂定电位电解法＂的手持SO2分析仪有正干扰,并得出了干扰系数。现场实地测试后,利用干扰系数对监测数据进行人工修正,对比结果合格。应用＂定点位电解法＂监测烧结机烟气中低浓度SO2时,应人工修正或加装剔除CO影响的元件。     

基于人口的COD、SO_2排放基尼系数分析

对各类污染物排放实行总量控制计划管理是国家环境政策的必然趋势,科学评价区际排污权分配方案的合理性是其中的一项基础工作。以《国民经济和社会发展第十一个五年规划纲要》中关于各省区化学需氧量（COD）、二氧化硫（SO2）排放总量分配方案为研究对象,应用基于人口的Gini系数法定量评价该方案的合理性。评价结果表明,以人口存量为参考标准,COD排放权分配的基尼系数为0.1643,处于高度平均区间内;SO2排放权分配的基尼系数为0.2277,处于相对平均区间内。总体上该方案具有较强的合理性,影响两种污染物排放权分配合理性的关键因子不尽相同,影响强度也存在显著差别。     

Preparation of activated carbons from unburnt coal in bottom ash with KOH activation for liquid-phase adsorption

In this work, unburnt coal (UC) in bottom ash from coal-fired power plants was soaked in KOH solution and activated for 1 h at 780 °C. The yield of activated carbons varied from 47.8 to 54.8% when the KOH/UC weight ratio changed from 2 to 4. Pore properties of these activated carbons including the BET surface area, pore volume, pore size distribution, and pore diameter were characterized based on N₂ adsorption isotherms. It was shown that the isotherms for the adsorption of methylene blue, acid blue 74, and 4-chlorophenol from aqueous solutions on these activated carbons at 30 °C were well fitted by the Langmuir equation (correlation coefficient r² > 0.9968). The adsorption capacities of methylene blue, acid blue 74, and 4-chlorophenol were obtained to be 2.40–2.88, 0.57–1.29, and 2.34–5.62 mmol/g, respectively. Moreover, the adsorption kinetics could be suitably described by the Elovich equation.     

Adsorption-desorption characteristics of mercury in paddy soils of China

Mercury (Hg) has received considerable attention because of its association with various human health problems. Adsorption-desorption behavior of Hg at contaminated levels in two paddy soils was investigated. The two representative soils for rice production in China, locally referred to as a yellowish red soil (YRS) and silty loam soil (SLS) and classified as Gleyi-Stagnic Anthrosols in FAO/UNESCO nomenclature, were respectively collected from Jiaxin County and Xiasha District of Hangzhou City, Zhejiang Province. The YRS adsorbed more Hg(2+) than the SLS. The characteristics of Hg adsorption could be described by the simple Langmuir adsorption equation (r2 = 0.999 and 0.999, P < 0.01, respectively, for the SLS and YRS). The maximum adsorption values (Xm) that were obtained from the simple Langmuir model were 111 and 213 mg Hg(2+) kg(-1) soil, respectively, for the SLS and YRS. Adsorption of Hg(2+) decreased soil pH by 0.75 unit for the SLS soil and 0.91 unit for the YRS soil at the highest loading. The distribution coefficient (kd) of Hg in the soil decreased exponentially with increasing Hg(2+) loading. After five successive desorptions with 0.01 mol L(-1) KCl solution (pH 5.4), 0 to 24.4% of the total adsorbed Hg(2+) in the SLS soil was desorbed and the corresponding value of the YRS soil was 0 to 14.4%, indicating that the SLS soil had a lower affinity for Hg(2+) than the YRS soil at the same Hg(2+) loading. Different mechanisms are likely involved in Hg(2+) adsorption-desorption at different levels of Hg(2+) loading and between the two soils.     

株洲市臭氧污染状况及相关气象因子分析

采用2013年1～12月空气质量自动监测数据对株洲市臭氧污染现状及相关气象因子进行分析。结果表明:监测期间全年臭氧日最大8 h平均浓度一级标准值达标率达到71.8%,全年超标率为1.6%,超标主要出现在季节变换时期。臭氧日最大8 h平均浓度的月均值变化呈"M"型,浓度高值持续时间长。日变化规律较强,且不同季节变化特征略有差别。臭氧浓度与气温有正相关性,相关系数为0.612;与湿度和云量有负相关性,且臭氧与湿度负相关性较明显,相关系数为0.731。     

TRANSPORT CHARACTERISTICS OF PHOSPHORUS IN CHANNELIZED AND MEANDERING STREAMS1

ABSTRACT: Comparisons were made between rates of movement of orthophosphate in a canal and a meandering stream. The meander system had greater algal and macrophyte phosphate uptake rates, and lower plankton and sediment release rates compared to the canal. Chemical precipitation and direct rainfall influences on orthophosphate movement were insignificant relative to other terms. The major source of phosphorus to both systems was from upland runoff. The impact of this source was greater on the meandering system due to the smaller channel volume. When secondary effects of meandering were considered such as marsh inundation, the net orthophosphate movement within the meandering channel was less than that for the canal; due to the lower concentrations of phosphorus in marsh effluent waters. Field experiments were conducted to compare the longitudinal dispersion coefficient between a canal and meandering river system; the meandering stream had a dispersion coefficient over 17 times that measured for the canal. Rates of orthophosphate movement were combined into a single mass transport equation, and a numerical solution was obtained. Internal river and canal channel processes were overshadowed by external point source loadings.     

室内挥发性有机化合物综合散发量及其特征

基于室内建筑污染源散发特性与汇效应机制分析,给出了建筑室内挥发性有机化合物（VOCs）综合散发量的计算模型,并进一步分析了材料内部扩散系数、气固界面分离系数和材料厚度对室内VOCs综合散发量的影响特征。研究结果表明,在近似稳定阶段室内VOCs综合散发量会随源材料内部扩散系数的增大而升高,而随源材料气固界面分离系数和材料厚度的增加而减小,且以源材料内部扩散系数的影响最为显著;同时,室内汇表面三类参数的增大均会使室内VOCs综合散发量降低;此外,在相同的环境参数条件下,室内VOCs综合散发量会因室内汇效应的存在而减小。     

弹性系数在“绿色GDP”核算研究中的应用

本文总结了四川省在"中国环境经济核算体系总体框架"下"绿色GDP"核算结果的局限性,进而提出了"绿色弹性系数"的概念,并比较分析了2005~2007年四川省各地区的"绿色弹性系数",有效地反映了环境污染负荷的变化与社会经济的发展相互制约的关系以及发展趋势和规律。     

Estimating turf pesticide volatilization from simple evapotranspiration models

A previously developed model by Haith et al. (2002) related pesticide volatilization from turf to evapotranspiration (ET) by scaling factors determined from vapor pressures and heats of vaporization. Although the model provided volatilization estimates that compared well with field measurements, it relied on the Penman ET equation, requiring hourly temperature, wind speed, and solar radiation data, none of which are routinely available at field sites. The current study determined that the volatilization model works equally well with a simpler ET equation requiring only daily temperatures. Three daily temperature-based ET models were evaluated as vehicles for estimating pesticide volatilization from turf: Hamon, Hargreaves-Samani, and a modified Priestley-Taylor. When compared with field volatilization measurements for eight pesticides, volatilization estimates produced from the Hargreaves-Samani model most closely approximated both the field observations and the previous estimates based on the more data-intensive Penman model. Mean estimated volatilization exceeded mean observations by 15% and the coefficient of variation (R2) between estimates and observations was 0.65. The comparable values based on Penman ET were 17% and 0.63, respectively.     

AN ALGORITHM FOR ESTIMATING SURFACE SUSPENDED SEDIMENT CONCENTRATIONS WITH LANDSAT MSS DIGITAL DATA1

ABSTRACT: Algorithms for Landsat MSS digital data are needed to reduce the necessity of calibrating each Landsat scene if these data are to be useful in monitoring programs for surface suspended sediments. In this study digital data were extracted from 16 Landsat Multispectral Scanner (MSS) scenes collected between March 1987 and August 1988 over Enid Reservoir in North Central Mississippi. These data were converted to radiance and reflectance data for comparison with field measurements of surface suspended sediment concentrations. Concentrations ranged from 2 to 168 mg/1 during the study with only four greater than 100 mg/l. Linear and polynomial regression analyses were used to relate the surface suspended sediment concentrations with radiance and reflectance. Reflectance in MSS band 2 (0.6 to 0.7 μm) and MSS band 3 (0.7 to 0.8 μm) were best related to the surface suspended sediment concentrations with coefficients of determination accounting for 71 percent and 68 percent of the variation in the data, respectively. Regressions with radiance data accounted for 36 percent (band 2) or less of the variation. Logarithmic transformations of either reflectance or sediment concentrations increase the coefficients of determination for MSS band 2 reflectance data to 81 percent. Regressions between the ratio of MSS band 1 to MSS band 2 reflectances and concentrations also accounted for 80 percent of the variation. An equation Log_e SS (mg/l) = 9.21R½+ 2.71R½2 + 8.45, where S is surface suspended sediment concentrations and R¹/₂ is the ratio of MSS band 1 to MSS band 2 reflectances, provided the best fit to the data with a coefficient of determination of 0.82. This equation is essentially the same as an algorithm proposed by Topliss et at. (1990), for estimating surface suspended sediment concentrations in Canadian coastal waters. These equations for Enid Reservoir and Canadian waters suggest that it may be possible to develop an algorithm for widespread use for estimating surface suspended sediments.