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.     

钙钛矿型催化剂催化湿式氧化处理煤气化废水纳滤浓缩液

采用溶胶-凝胶法制备了Mn掺杂钙钛矿型催化剂LaFexMn1-xO3，并以其为催化剂催化湿式双氧水氧化处理煤气化废水纳滤浓缩液。采用XRD，SEM，FTIR技术对催化剂进行了表征。表征结果显示：制备的催化剂均具有标准的钙钛矿型结构，其中，LaFe0.9Mn0.1O3的结构稳定，比表面积大。实验结果表明：制备的催化剂中LaFe0.9Mn0.1O3的催化活性最高，且稳定性好，连续使用5次后催化活性未见明显减弱；在H2O2投加量3.0 g/L、n（H2O2）∶n（LaFe0.9Mn0.1O3）=12∶1、反应温度160 ℃、反应压力1 MPa、浓缩液pH 3、反应时间60 min的最优条件下，COD、UV254和TOC的去除率分别达到80.9%、95.2%和68.0%，BOD5/COD由0.02提升至0.40，可生化性大幅提高。     

300MW锅炉低NOx燃烧系统改造效果分析

针对日益严重的环境污染、锅炉热效率低等问题，阐述了燃煤锅炉炉内空间分级燃烧技术、煤粉浓淡高效分离技术改造项目和特点，提出了对燃烧器系统、一次风管道、二次风系统和空预器系统等系统进行具体的低氮改造措施。分析了300 MW燃煤锅炉低氮改造后的热经济性和安全性。经试验验证，1号锅炉低氮改造后，锅炉NOx 排放量大幅减少，排放浓度降到了280 mg／m3。     

纳米铁氧化物吸附处理重金属废水的研究进展

概述了用于吸附重金属的主要纳米铁氧化物的种类及其吸附效果,介绍了常见的纳米铁氧化物制备方法及改性方法,讨论了影响纳米铁氧化物吸附重金属的主要因素,并对纳米铁氧化物在水环境保护领域中的研究方向提出了展望:如发展绿色、高效的纳米铁氧化物制备工艺,探讨纳米铁氧化物结构调控和表面功能化对其吸附性能的影响等。     

Packed in-tube solid phase microextraction with graphene oxide supported on aminopropyl silica: Determination of target triazines in water samples

On-line in-tube solid phase microextraction (in-tube SPME) coupled to high performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) was successfully applied to the determination of selected triazines in water samples. The method based on the employment of a packed column containing graphene oxide (GO) supported on aminopropyl silica (Si) showed that the extraction phase has a high potential for triazines extraction aiming to its physical-chemical properties including ultrahigh specific surface area, good mechanical and thermal stability and high fracture strength. Injection volume and loading time were both investigated and optimized. The method validation using Si-GO to extract and concentrate the analytes showed satisfactory results, good sensitivity, good linearity (0.2–4.0 µg L^?1) and low detection limits (1.1–2.9 ng L^?1). The high extraction efficiency was determined with enrichment factors ranging from 1.2–2.9 for the lowest level, 1.3–4.9 intermediate level and 1.2–3.0 highest level (n = 3). Although the analytes were not detected in the real samples evaluated, the method has demonstrated to be efficient through its application in the analysis of spiked triazines in ground and mineral water samples.     

模糊控制技术在污水处理中的应用

针对污水处理过程中采用传统的流量程序控制和时间程序控制的不足,提出了一种基于单片机的模糊控制方法。该方法以污水流量、溶解氧(DO)浓度和污泥回流比为主要被控对象,以DO浓度为主要控制参数,通过离散计算和在线查表的模糊推理方法可得到最佳的风机转速,使污水处理生化池内DO浓度保持在最佳状态,同时还通过控制曲线展示了当输入污水流量发生扰动时对DO浓度的控制精度,使污水处理质量保持稳定。通过实际应用表明,该控制方法不但能确保出口净化水水质达标,还可以节约15%的电能。     

氢氧化钽对水体中磷酸盐的吸附去除作用

采用氢氧化钽为吸附剂,对水中磷酸盐的吸附性能进行了研究,考察了吸附时间、pH值、磷酸盐的初始浓度、反应温度对吸附量的影响。实验结果表明:pH值越小,氢氧化钽对磷酸盐的吸附量越大,当pH值为2时氢氧化钽对磷酸盐的吸附性能优,并且pH值对磷酸盐的吸附量影响较大;磷酸盐的初始浓度越大,吸附量越大,吸附平衡时间越短;氢氧化钽对磷酸盐的吸附量和吸附速率都随着温度的升高而增加。在25℃、pH=2、初始浓度为200 mg/L、吸附30 min时达到平衡时最大吸附量为76.69 mg/g。吸附后的氢氧化钽红外谱图在1066 cm-1处出现特征峰,该峰恰好是吸附磷酸盐的伸缩振动峰,并且在638 cm-1与670 cm-1之间Ta-O键由于磷酸盐的吸附发生了蓝移。采用6 mol/L的NaOH对吸附了磷酸盐的氢氧化钽进行解吸,当pH=12时解吸率为52.45%。研究结果表明,氢氧化钽能够有效的去除水溶液中磷酸盐的吸附剂。     

Shellac-coated iron oxide nanoparticles for removal of cadmium(II) ions from aqueous solution

This study describes a new effective adsorbent for cadmium removal from aqueous solution synthesized by coating a shellac layer, a natural biodegradable and renewable resin with abundant hydroxyl and carboxylic groups, on the surface of iron oxide magnetic nanoparticles. Transmission Electron Microscopy (TEM) imaging showed shellac-coated magnetic nanoparticle (SCMN) adsorbents had a core-shell structure with a core of 20 nm and shell of 5 nm. Fourier Transform Infrared Spectroscopic analysis suggested the occurrence of reaction between carboxyl groups on the SCMN adsorbent surface and cadmium ions in aqueous solution. Kinetic data were well described by pseudo second-order model and adsorption isotherms were fitted with both Langmuir and Freundlich models with maximum adsorption capacity of 18.80 mg/g. SCMN adsorbents provided a favorable adsorption capacity under high salinity conditions, and cadmium could easily be desorbed using mild organic acid solutions at low concentration.     

春季黄渤海溶解有机碳的平面分布特征

依据2010年4～5月对黄渤海调查所得的数据,分析了黄渤海溶解有机碳(dissolved organic carbon,DOC)的含量及其平面分布特征,并对其影响因素进行了初步探讨.结果表明,2010年春季黄渤海DOC的浓度范围为0.96～4.71 mg.L-1,平均浓度为2.27 mg.L-1.平面分布上,DOC整体呈现南北近岸浓度高、中部外海浓度低的特点.在渤海西部近岸、山东半岛东部及长江口东北部均存在高值,尤其是渤海西部近岸,DOC浓度最高达到4.71 mg.L-1,这主要是受河流输入和沿岸流的影响;低值区则主要集中在南黄海中部外海,DOC浓度普遍低于1.50 mg.L-1.     

Dissolved organic sulfur in streams draining forested catchments in southern China

Dissolved organic sulfur (DOS) is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. Dissolved sulfur was fractionated into dissolved organic sulfur (DOS) and inorganic sulfate (SO₄^2-) for 95 stream water samples. The results showed that the concentration of DOS ranged from 0 to 13.1 mg/L (average 1.3 mg/L) in all the streams. High concentrations of DOS in stream waters were found in the sites with high concentrations of sulfate. DOS constituted less than 60.1% of dissolved sulfur (average 17.9%). Statistical analysis showed that DOS concentration was correlated with SO₄^2- in streams waters and total sulfur in surface layer soils. The results also showed that DOS concentration in stream waters had a seasonal variation, but no trends were found with it. The implication was that the long term sulfur deposition had led the increase of the concentration and fraction of DOS in stream waters in acid rain prevailing regions