利用合成沸石副产稀碱液制五水偏硅酸钠

合成沸石原粉副产和稀碱液经除杂后，用泡花碱调整ＳｉＯ２浓度，再经浓缩、结晶、分离、干燥等过程制备五水偏硅酸钠，产品质量符合标准，生产成本较通常方法可降低２５％，采用本法还可解决稀碱液对环境的污染，具有较好的环境、经济和社会效益。     

Are calcareous soils in uplands less prone to damage from road salting than acidic soils?

Previous studies of upland roadside soils in Cumbria, that would normally be naturally acidic, have highlighted that (a) runoff from roads subjected to long-term road salting can dramatically raise soil pH down slope in upland areas; (b) the soil pH increase dramatically changes N cycling in soils down slope, increasing mineralisation of organic matter, ammonification, ammonium leaching down slope and nitrification and nitrate leaching; (c) the increase in nitrification substantially increases nitrate leaching to down-slope rivers, and this is readily detectable in field studies; and (d) loss of soil organic matter over decades of salting is so great that organic matter is no longer substantially solubilised by high salt concentrations found in soil solution below road drains. This paper tests and supports the hypothesis that such effects are minimal for more calcareous soil ecosystems. It examines the soil and soil solution chemistry on another Cumbrian upland highway, the A686 near Leadgate, Alston. Sodium % of soil CEC values for soil transects affected by spray containing road salt are similar at both the A6 and A686 sites. However, spatial trends in calcium, magnesium, ammonium, and nitrate concentrations as well as pH differ, as a direct result of the higher weathering rate of parent material and possibly also the presence of limestone walls above both spray-affected and control transects at the A686 site.     

Determination of andrographolide sodium bisulfite in renal microdialysis fluid of rats and toxicokinetic study

Abstract

Andrographolide sodium bisulfite (ASB) widely used for intestinal infections and respiratory tract infections. It has been reported to frequently cause acute renal failure in clinical practice. The purpose of this study was to evaluate the nephrotoxicity and toxicokinetics in Sprague-Dawley rats after a single-dose injection of ASB administered at 100, 600, and 1000?mg/kg via intravenous tail injections. The concentrations in plasma and kidney microdialysates were analyzed by high-performance liquid chromatography. Blood urea nitrogen and creatinine levels in plasma were determined and toxicokinetic parameters were observed. In plasma and kidney, the elimination constant and clearance were decreased and the half-time was increased with increasing dose. Blood urea nitrogen and creatinine were positively correlated with ASB concentration indicating the potential for accumulation in kidney that can eventually lead to damage.     

Effect of calcination temperature on the application of sodium zirconate solid base catalyst for biodiesel production from Jatropha curcas oil

Influence of catalyst calcination temperature on the catalyst characteristics and catalytic transesterification of Jatropha curcas oil for biodiesel production was studied by using sodium zirconate (Na₂ZrO₃) solid base catalyst. Na₂ZrO₃ catalysts were prepared by impregnation method followed by calcination at temperatures of 700, 800, and 900°C. The prepared catalysts were characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. Important parameters influencing the catalytic activity and fatty acid methyl ester yield were investigated. It was found that the increase in calcination temperature showed marked increase in activity due to the increased porosity and presence of tetragonal zirconia. Investigation of the reusability of the catalysts showed that the catalytic activity was retained even after five cycles of reaction.     

糖精钠生产废水的铁氧体法除铜研究

对糖精钠生产废水实施铁置换法除铜后，废水中仍含有较高浓度的Ｃｕ＾２＋。本研究进一步以铁氧体法除铜。试验条件下，Ｃｕ６２＋的去除率达９８％Ｔ以上，出水Ｃｕ＾２＋浓度低于２．５ｍｇ／Ｌ。通过正交试验，找出最佳工艺及操作参数，从而为该类废水的预处理设计及运行管理提供屯依据。     

流动分析法测定空气和废气中氨的研究

建立流动分析法测定吸收液中氨的方法,用稀硫酸溶液吸收空气中的氨气,吸收液作为样品进入流动分析系统,采用在线蒸馏,实行自动分析,与国家标准方法比对,无明显差异,可用于空气中氨的定量检测。     

钠盐类型对表面活性剂清洗煤油污染土壤的强化效应

采用表面活性剂清洗煤油污染土壤,考察添加钠盐对洗脱率的影响,并用Zeta电位仪、表面张力仪对溶液及用接触角仪对清洗前后的土壤进行表征.结果表明,硅酸钠对十二烷基硫酸钠(SDS)清洗的增效作用最明显;酒石酸钠对十二烷基苯磺酸钠(SDBS)及聚氧乙烯月桂醚(Brij35)清洗的增效作用最明显;不同类型钠盐对曲拉通X-100(TX-100)清洗均有一定的增效作用但差别不明显;腐殖酸钠及硅酸钠对皂苷溶液清洗的增效程度相当,但就改良土质而言选用腐殖酸钠作助剂更为合适;硅酸钠对Tw-80清洗的增效作用随着Tw-80浓度的增大而增强,氯化钠和酒石酸钠则相反.钠盐增效清洗的作用机制是降低离子型表面活性剂的表面张力和临界胶束浓度;而非离子型表面活性剂的增效作用则是利用钠盐防止煤油"重吸附"及抗表面活性剂"沉淀",增大胶团体积来实现.接触角测量表明,煤油污染后的土壤亲水性减弱,清洗后接触角变小,亲水性增强,且随着表面活性剂浓度的增大接触角减小,对恢复土壤运输水分和养料正常功能有利.     

磷酸二氢钠去除铀的效果与机理

通过静态实验,研究了不同反应时间、p H值、初始铀浓度、磷酸二氢钠用量、温度等因素对磷酸二氢钠去除溶液中铀的效果的影响,并结合红外光谱、扫描电镜和热重分析等测试结果,探讨了磷酸二氢钠去除铀的机理.结果表明,一定质量的磷酸二氢钠对铀的去除量随着铀初始浓度的增大而增大,随着温度的升高而减小;在p H值为5,磷酸二氢钠用量为2.0 mg时,磷酸二氢钠去除铀的效果最好,铀的去除率高达99%以上;反应在120 min基本达到平衡.红外光谱分析说明磷酸二氢钠主要是通过磷酸二氢根与UO2+2发生络合反应去除溶液中的铀,扫描电镜分析显示反应生产了矿物晶体,热重分析可知该矿物晶体具有很好的热稳定性.     

三维花状结构α-FeOOH协同H2O2可见光催化降解双氯芬酸钠

采用油浴回流法,在常压回流反应条件下批量制备出三维花状结构的α-Fe OOH纳米材料,并利用XRD、FT-IR和SEM等仪器对其进行分析表征;以双氯芬酸钠为目标污染物,考察三维花状结构α-Fe OOH纳米材料,在模拟太阳光照射下,催化H2O2降解有机污染物的性能.结果表明,三维花状结构α-Fe OOH由纳米棒自组装形成,纳米棒的长度约400~500 nm,直径约40~60 nm.以模拟可见光为光源,三维花状结构α-Fe OOH与H2O2构成光助异相类Fenton体系,对双氯芬酸钠有良好的光催化降解效果,在90 min内对初始浓度为30 mg·L-1的双氯芬酸钠降解去除率达到99%以上,催化降解反应以羟基自由基氧化反应为主.     

次氯酸钠氧化预处理草甘膦生产废水

利用次氯酸钠对草甘膦生产废水进行预处理，废水ｐＨ对处理效果影响不大，可将次氯酸钠直接投入到原碱性废水中，在其用量相当理论量的４０％、氧化时间为４ｈ时，草甘膦的去除率为９８％。预处理后的废水对厌氧消化过程不再产生抑制作用。