包头市大气氟化物排放总量控制管理研究

结合实践,阐述了总量控制管理的必要性和可能性;介绍和分析了总量管理的内容和程序;对主要问题提出对策和措施;形成运行管理机制,提出排氟量计算、污染物输送扩散模型等构成的技术支持系统。      

不同日摄氟量居民罹患氟斑釉的研究

人和动物体内的硬组织（牙齿、骨骼等）是氟化物作用的主要部位,严重者可引起氟骨症和氟斑釉,其中氟斑釉是慢性氟中毒的一项特异指标。通常日摄氟量高的居民其氟斑釉率和斑釉指标均增高。本文用日摄氟量作指标评价环境氟对居民牙齿的影响。研究结果揭示,当地居民的斑釉率和斑釉指数均与日摄氟量呈非常显著的正相关,r＝0.9084,P<0.01。     

高效液相色谱法测定茶叶和土壤中的氟

建立了测定氟的高效液相色谱法,并通过加入三乙胺使Ｆ－Ｌａ＾３＋－苯素氨羧络合剂体系更稳定。Ｃ１８柱,甲醇－水（１８：８２）作流动相,流速为１ｍｌ／ｍｉｎ,检测波长为５６６ｎｍ,本法线性范围为０．０１０－１．０μｇ／ｍｌ,相关系数为０．９９１,检出限为１ｎｇ／ｍｌ,用于茶叶和土壤样品测定时,相对标准偏差为４．６％－７．３％,加标回收率为９１％￣１０４％。     

用氟化钾水溶液从制药废液中回收吡啶

研究了普通精馏与加盐分相技术在回收吡啶中的应用。测定了吡啶 水 氟化钾体系在25℃时的液液相平衡数据,采用Pitzer理论和UNIQUAC方程对相平衡数据进行了理论计算,结果表明计算值与实验值符合良好。采用氟化钾水溶液回收吡啶,当60%氟化钾浓溶液与50%吡啶/50%水的物料的质量比为2.0时,有机相中吡啶的纯度可达到92.60%(质量分数),水相中氟化钾稀溶液经蒸发回收后循环使用不影响分离性能。该工艺的开发成功为制药行业从制药废液中回收吡啶开辟了一条新途径。     

流动注射分光光度法测定水中痕量氟化物

研究并建立了测定水中痕量氟化物的氟试剂（ＡＬＣ）－流动注射分光光度法。将水样注入到水载流中,与ＡＬＣ－Ｌａ丙酮水溶液混合,在５０℃时反应生成蓝色三元络合物,在分光光度计上于波长６１８ｍｍ处进行检测。Ｆ＾－测定的线性范围为０．０４－３．０ｍｇ／Ｌ,检出限为０．０３６ｍｇ／Ｌ。     

Hydrochemistry of drinking water sources and water purifiers in relation to epidemiological study in Hisar,North-West India

The concern related to the drinking of reverse osmosis (RO) water containing low levels of minerals is growing day by day. This study involves the analysis of water samples from various drinking water sources in a rural site, Mirchpur village, an Indus Valley civilization site (grid location: 29° 18′ 42.3″ N, 76° 10′ 33.0″ E) of Hisar, India, along with the health survey of human subjects. The hydrochemistry of water collected from hand pumps, river canals, tube wells, submersibles, and the RO systems installed in various homes was explored for pH, EC, TH, TDS, turbidity, cations (Na⁺, Ca²⁺, Mg²⁺), anions (CO₃²⁻, HCO₃⁻, Cl⁻, SO₄²⁻, NO₃⁻, F⁻), and elements (Fe, Pb, Se) employing the ion chromatography, flame photometry, and ICP-AES techniques. Lead (Pb) and Selenium (Se) were detected in trace amounts (0.30–2.6 μg L⁻¹; 0.10–4.1 μg L⁻¹, respectively) in all the samples, including the samples collected from RO purifiers, but Iron (Fe) was not detected in RO samples even in trace amounts. The F-levels in hand pump water (HPW) and submersible water (SW) (1.9  and 1.7 mg L⁻¹, respectively) and TDS levels in SW (3048 mg L⁻¹) were found to be above WHO and BIS safe limits. TDS levels in the river canal (900 mg L⁻¹), tube well (1104 mg L⁻¹), hand pump (1170 mg L⁻¹), and submersible samples (3048 mg L⁻¹) were found significantly higher as compared to the RO personal water (ROPW; 216 mg L⁻¹) and RO supply water (ROSW; 90 mg L⁻¹). The collected epidemiological data reveals that 21%, 19%, 13%, and 12% of natives reported skin, kidney, hair fall, liver, and stomach issues, respectively, suspecting the crucial role of high TDS and fluoride levels in the area. This study also provides a comparison between the quality of RO and the direct supply water, along with correlation matrices for different parameters, which gives a rationale for the limitations of drinking direct supply water without any purification and RO water containing low mineral content.     

Nexus between polymer support and metal oxide nanoparticles in hybrid nanosorbent materials (HNMs) for sorption/desorption of target ligands

Metal oxide nanoparticles like hydrated ferric oxide (HFO) or hydrated zirconium oxide (HZrO) are excellent sorbents for environmentally significant ligands like phosphate, arsenic, or fluoride, present at trace concentrations. Since the sorption capacity is surface dependent for HFO and HZrO, nanoscale sizes offer significant enhancement in performance. However, due to their miniscule sizes, low attrition resistance, and poor durability they are unable to be used in typical plug-flow column setups. Meanwhile ion exchange resins, which have no specific affinity toward anionic ligands, are durable and chemically stable. By impregnating metal oxide nanoparticles inside a polymer support, with or without functional groups, a hybrid nanosorbent material (HNM) can be prepared. A HNM is durable, mechanically strong, and chemically stable. The functional groups of the polymeric support will affect the overall removal efficiency of the ligands exerted by the Donnan Membrane Effect. For example, the removal of arsenic by HFO or the removal of fluoride by HZrO is enhanced by using anion exchange resins. The HNM can be precisely tuned to remove one type of contaminant over another type. Also, the physical morphology of the support material, spherical bead versus ion exchange fiber, has a significant effect on kinetics of sorption and desorption. HNMs also possess dual sorption sites and are capable of removing multiple contaminants, namely, arsenate and perchlorate, concurrently.     

高氟病区茶园土壤氟形态及其分布特征

采用连续化学提取法,测定了黔西北高氟病区茶园土壤样品氟含量及氟的形态.结果表明:供试土壤全氟含量为314~3558mg/kg,平均为945mg/kg,高于全国土壤全氟平均含量(453mg/kg).不同类型供试土壤中全氟含量高低顺序为:棕壤和褐土(分别为1118和1114mg/kg)>黄棕壤(908mg/kg)>黄壤(681mg/kg).供试土壤中不同形态氟含量以残余态最高,其平均含量为940mg/kg;其次为有机束缚态氟,平均含量为7.82mg/kg,处于氟污染较高水平,可能会对人体健康和生态环境产生重要影响;铁锰结合态氟也较高,平均含量3.99mg/kg;水溶态氟和可交换态氟均较低,其平均含量分别为:1.98,1.14mg/kg.由此可见,土壤中氟形态大部分均以残余态形式存在于土壤中,可被茶树叶吸收的水溶态氟和可交换态氟含量均不高.相关性分析表明:可交换态氟只与水溶态氟呈显著正相关关系(r=0.459**),而水溶态氟与铁锰结合态氟、残余态氟和全氟均呈正相关关系(r分别为0.240*, 0.226*, 0.229*), 有机束缚态氟与铁锰结合态氟、残余态氟和全氟也呈正相关关系(r分别为0.757**, 0.312**, 0.320**),水溶态氟与土壤交换性盐基含量之间也呈极显著正相关关系,而土壤氟形态与有机质的相关性不明显,仅有机束缚态氟与土壤有机质呈弱负相关.本研究可为该区域土壤氟污染防治提供科学依据,也为土壤氟的迁移转化及其对生态和环境的影响研究奠定一定的理论基础.     

山阴水砷中毒区地下水砷的富集因素分析

通过对山阴地区66个地下水样中常量元素、微量元素及有机物分析,研究了山阴高砷地下水的水化学特性并在此基础上,结合该地区含水层沉积物矿物分析,探讨了地下水中砷富集的影响因素.结果表明,山阴地下水平均pH为8.09,磷酸根含量为0.71mg/L,溶解性有机物含量为5.14 mg/L,以及地下水处于还原环境.高pH值、高磷酸根含量及还原环境不利于含水介质对以阴离子形式存在的砷的吸附,高溶解性有机物含量则增加了砷的活性这些因素促使了含水介质中砷的解吸和迁移.     

Automated indirect fluoride determination by ICP-OES using discontinuous-flow analysis

An automated method for the indirect determination of fluoride by inductively coupled plasma atomic emission spectrometry using discontinuous-flow analysis has been developed. A modified flow injection analysis system was used for sample preparation. The method is based on the determination of excess cerium(III) ion after precipitation of CeF₃. Separation of the precipitate is performed online on a syringe membrane filter that is cleaned each analysis cycle by 1 M nitric acid, ensuring a long life-time for the filter. As a result of the short reaction time, a detection limit of 9.5 mg L^?1 was obtained. The precision (RSD) of the proposed method is 1.02% at fluoride concentration of 28 mg L^?1. The applicability of the technique for groundwater monitoring of fluoride-contaminated area is demonstrated.