PACS的结构特征及絮凝性能研究

制备了碱化度及Ａｌ＾３＋／ＳＯ＾２－４摩尔比不同的系列ＰＡＣＳ，分别进行常压（干燥温度１０５℃）及真空干燥（真空度为－０．０９８ＭＰａ、干燥温度６５℃）制备固体产品。用红外光谱及Ｘ－射线衍射谱研究了碱化度、Ａｌ＾３＋／ＳＯ＾２－４摩尔比、干燥温度对ＰＡＣＳ的结构影响，比较了干燥温度不同对ＰＡＣＳ固体样品的溶解度及絮凝效果的影响，借助于显微电泳测定技术研究不同碱化度及不同Ａｌ＾３＋／ＳＯ＾２－４摩尔     

用化学发光法测定雨水中的氨

本文研究了用ＴＣＰＯ－Ｈ２Ｏ２发光体系对氨进行测定。结果表明，当ｐＨ＝１０．３，ＯＰＡ浓度为１０ｍｍｏｌ．ｌ＾－１，氨浓度在０－６ｍｇ．ｌ＾－１时，其浓度和发光强度有良好的线性关系（相关系数为０．９９８），本法的最低检出限为２ｎｇ．ｌ＾－１。可用于实际雨水样品的测定，测定结果还表明：本法具有灵敏度高，精度高，线性范围宽干扰少等优点，适用于大批量分析及连续自动监测分析。     

雨水中S（Ⅳ）的离子色谱分析及其保护方法的研究

本文研究了用离子色谱法分析雨水中Ｓ（Ⅳ）的色谱条件和含Ｓ（Ⅳ）样品的保存方法，采用ＨＰＩＣ＿ＡＳＡ分离柱、用２ｍｍｏｌ．ｌ＾－１Ｎａ２ＣＯ３／３ｍｍｏｌ．ｌ＾０１ＮａＯＨ溶液作淋洗液、０．０１２５ｍｏｌ．ｌ＾－１Ｈ２ＳＯ４为再生液、电导检测的方法，具有无干扰和灵敏度高等优点，而且在Ｓ（Ⅵ）的浓度秋－２８μｇ．ｍｌ＾－１范围内，其浓度与响应值之间呈现出良好的线性关系，其线性相关系数在０．９９９５以上     

离子色谱法测定饮用水和面包中的溴酸根

选用ＡＳ９－ＨＣ高容量阴离子交换色谱柱,不需处理除去干扰离子,可直接进样。测定了两种水样,其中一种检出溴酸根,方法检出根０．００５ｍｇ．１＾－１水样加标回收率９１．３－９３．４％。采用全新的自动化样品处理技术－加速溶剂萃取萃取面包中的溴酸根。经ＡＳ９－ＳＣ阴离子交换色谱柱分离,选择最佳淋洗条件。电导检测,方法检 ０．０７ｍｇ．１＾－１,对十二种市售包进行测定,均未检出溴酸根,样品加标回收率７９．９     

次氯酸钠光度法测定污水中的苯胺

本文对ＮａＣｌＯ为氧化显色剂，亚硝基铁氰化剂，测定污水中的苯胺。当λｍａｘ为６９４ｎｍ时，εｍａｘ为３×１０＾４，最低检出限为０．０１ｍｇ／１，０－２０ｍｇ／ｌ的苯胺溶液的线性相关系数为０．９９９８。应用本法测定炼厂和采油厂排放的污水，与萘乙二胺偶氮光度法的测定结果基本吻合。可消除石油类、苯酚、氨、硫化物及某些金属离子的干扰，是一种简便。快速的分析方法。     

离子色谱法测定海水中的铵离子

采用新型柱填料的阳离子色谱柱,改善了铵离子与钾离子,钠离子的分离度,消除了大量钾离子和钠离子对铵离子测定的干扰。在硫酸和甲烷磺酸两种分离体系中,铵离子的检出限分别达到０．１ｍｇ．ｌ＾－１和０．０５ｍｇ．ｌ＾－１,线性范围分别为０．２－５０ｍｇ．ｌ＾－１和０．１－５０ｍｇ．ｌ＾－１。在两种淋洗条件下测定复杂基体海水中的铵离子,所得结果一致,该方法简便易行,灵敏度高。     

流动注射荧光分析法用于土壤及水系沉积物中铈（Ⅲ）含量的测定

研究表明Ｃｅ＾３＋在ｐＨ〈６．２ＫＣｌ介质中以２５４．０ｎｍ紫外光激发时，在３５２．０ｎｍ处发出具有恒定强度的荧光。因而可选择ｐＨ５－６作为测定酸度条件，利用Ａｌ２（ＳＯ４）３消除Ｆｅ＾３＋等离子的干扰，建立起Ｃｅ＾３＋的流动注射荧光分析法。方法的线性范围是２．０×１０＾－７—２．０×１０＾－６ｍｏｌ／ｌ，一元回归方程△Ｆ＝６６３６００Ｃ－０．０４１（ｎ＝１０，ｒ＝０．９９９７），检测限６．０×１     

高温脱除H2S的Mn—Fe／Al2O3脱硫剂研究

本文在热力学分析的基础上,制备了Ｍｎ－Ｆｅ／Ａｌ２Ｏ３脱硫剂,原料气中Ｈ２Ｓ浓度约为０．３％,空速约为３０００ｈ＾－１,在５５０－６５０℃的反应条件下,进行了脱硫反应实验,当出口Ｈ２Ｓ浓度大于０．０１％时,结束脱硫反应,在７１０℃,２４００ｈ＾－１空速的条件下,用１０．８３％的Ｏ２对脱硫剂进行再生,当出口ＳＯ２浓度低于０．００２％时,结束再生反应。     

磷和硫对空心菜吸收砷的影响

本文通过水培空心菜中砷与磷以及砷与硫配比试验，研究了ＰＯ＾３－４和ＡｓＯ＾３－４以及ＳＯ＾２－４和ＡｓＯ３＾３－４共存对空心菜生长及砷累积的影响。结果表明：５ｍｇ．ｌ＾－１ＰＯ＾３－４或ＳＯ＾２－４时，ＡｓＯ＾３－４显著降低空心菜产量，ＰＯ＾３－４和ＳＯ＾２－４含量提高到３０－１００ｍｇ．ｌ＾－１时，空心菜产量明显提高。．     

电感耦合等离子体—质谱法测定成人脏器样品中痕量稀土元素的研究

本文采用ＩＣＰ－ＭＳ法对成人脏器样品中痕量稀土元素进行了研究，选择了测定的最佳仪器参数，检查了测定中的各种干扰和影响；用铼（Ｒｅ）为内标元素补偿基体抑制效应和灵敏度的漂移。方法对稀土元素各分量的检出限为０．００５－０．０２６ｎｇ．ｍ１＾－１，标准回收率为９２．９－１１１．３％，精密度为０．９６－３．０７％。在严格分析质量控制的基础上用混合酸消解样品，不须分离富集，直接对成人的心、脾、肝、肾、肺肉中     

Investigation of naphthalene contamination in olive oil from Greece

Abstract

Incidents of using naphthalene in olive orchards as a repellent of olive fly (Bactrocera oleae) have recently been recorded. Naphthalene, the primary ingredient of mothballs, is described to be diluted in plastic bottles and hanged on the trees releasing its characteristic odor which is supposed to repel olive fly. Since naphthalene has been characterized as possibly carcinogenic to humans and animals, it was considered essential to monitor olive oils regarding their potential contamination with this specific pollutant. To this goal, a simple, sensitive and reliable analytical method for the determination of naphthalene in olive oil has been developed. The method involves extraction with ethyl acetate: acetonitrile (1:1) and determination of naphthalene using gas chromatography triple quadrupole mass spectrometry. The method was validated in four fortification levels, 0.005, 0.01, 0.05, and 0.1?mg/kg in accordance with the EU requirements. The obtained results were acceptable as far as validation criteria are concerned, given recoveries between 71% and 87% and RSDs between 5% and 24%. The limit of determination for naphthalene was set at 0.005?mg/kg based on the lowest concentration level being validated with acceptable accuracy. The analytical technique was successfully applied to 75 olive oil samples collected from oil mills in Greece and no positive results of naphthalene were detected.     

Abatement of sulfide generation in sewage by glutaraldehyde supplementation and the impact on the activated sludge accordingly

Hydrogen sulfide emission in sewer systems is associated with toxicity, corrosion, odour nuisance and high costs treatment. In this study, a novel method to inhibit sulfide generation from sewage by means of glutaraldehyde supplementation has been suggested and evaluated under anaerobic conditions. Different concentrations of glutaraldehyde at 10, 15, 20, 30 and 40 mg·L^-1 have been investigated. Besides, the possible impacts of glutaraldehyde supplementation on an activated sludge system and an appraisal of the economic aspects are presented as well. As observed from the experimental results, a dosage of 20 mg·L^-1 glutaraldehyde resulted in a significant decrease of the sulfide production by 70%–80% in the simulated sewage. Moreover, the impacts of additional glutaraldehyde at 20 mg·L^-1 on activated sludge, in terms of chemical oxygen demand removal and oxygen uptake rates, were negligible. From an economical point of view, the cost of the commercial glutaraldehyde products required in the operation, which was calculated on the basis of activated sulfide removal avoidance, was around €3.7–4.6 S·kg^-1. Therefore it is suggested that glutaraldehyde supplementation is a feasible technique to abate the sulfide problems in sewer systems. Yet further research is required to elucidate the optimum “booster” dosage and the dosing frequency in situ accordingly.     

二段生物接触氧化法处理含硫废水的中试研究

用二段生物接触氧化法探索炼油过程中所产生的含硫废水的处理新方法． 结果表明：经此工艺处理后的出水 Ｃ Ｏ Ｄ、氨氮、硫化物和酚的质量浓度ρ分别为２６６ ．９ ｍｇ／ Ｌ、８２ ．８５ ｍｇ／ Ｌ、１ ．１８ ｍｇ／ Ｌ 和１ ．４３ ｍｇ／ Ｌ,相应的去除率分别为８６ ．３ ％ 、４０ ％ 、９２ ．７ ％ 和９９ ．３ ％ ,出水水质达到国家三级排放标准． 进出水水质的变化曲线表明,生物接触氧化法处理含硫废水对进水水质变化的适应能力比较强,出水水质比较稳定,显示了二段接触氧化法处理含硫废水的可行性     

水中痕量亚当氏剂和二苯胺的固相微萃取方法研究

研究了固相微萃取(SPME)-高效液相色谱(HPLC)测定水样中痕量亚当氏剂和二苯胺的分析方法.对SPME的条件如萃取纤维、萃取时间、萃取温度、离子强度、解吸方式、解吸溶剂、解吸时间进行了优化,并用于地下水等实际水样的分析.SPME优化的条件为:选用60μmPDMS/DVB萃取纤维在室温25℃下直接萃取60min,磁力搅拌速度为1100r.min-1,然后萃取纤维在解吸室内静态解吸9min后进行HPLC分析.液相色谱分离条件为ZORBAXSBC18柱(4.6mmi.d.×250mm,5.0μm),流动相为甲醇-水(70:30,V/V),流速为1.0ml.min-1,二极管阵列检测器波长为280nm.方法线性范围为0.005mg.l-1—0.5mg.l-1(R>0.99),两种物质的检出限(S/N=3)分别为0.003mg.l-1和0.002mg.l-1.加标回收率分别在89.6%—100.4%和97.5%—100.1%(n=5)之间,相对平均标准偏差(RSD)分别在4.5%—6.2%和3.8%—6.7%之间.该方法快速、简便,无需使用有机溶剂,适于水样中痕量物质的分析.     

分散固相萃取-超高效液相色谱-串联质谱联用快速检测大豆及土壤中氟磺胺草醚残留

采用分散固相萃取(QuEChERS)样品前处理方法,建立了超高效液相色谱-串联质谱(UPLC-MS/MS)快速检测大豆和土壤中氟磺胺草醚的残留分析方法.大豆和土壤样品采用乙腈(含0.5%甲酸)提取,N-丙基乙二胺(PSA)或石墨化碳黑(GCB)净化,UPLC-MS/MS外标法检测定量.在0.005—0.5 mg.kg-1添加范围内,氟磺胺草醚在土壤、大豆和大豆植株中的平均回收率在79.4%—109.0%之间,变异系数在3.6%—10.1%之间.在山东、河南、吉林进行了氟磺胺草醚在大豆植株和土壤中的降解动态研究,结果表明,试验点中氟磺胺草醚在土壤中的降解半衰期为8.5—23.7 d;在大豆植株中的降解半衰期为2.7—9.8 d.     

New method for efficient control of hydrogen sulfide and methane in gravity sewers: Combination of NaOH and nitrite

• The combination of NaOH and nitrite was used to control harmful gas in sewers. • Hydrogen sulfide and methane in airspace were reduced by 96.01% and 91.49%. • Changes in sewage quality and greenhouse effect by chemical dosing were negligible. • The strong destructive effects on biofilm slowed down the recovery of harmful gases. • The cost of the method was only 3.92 × 10⁻³ $/m³. An innovative treatment method by the combination of NaOH and nitrite is proposed for controlling hydrogen sulfide and methane in gravity sewers and overcome the drawbacks of the conventional single chemical treatment. Four reactors simulating gravity sewers were set up to assess the effectiveness of the proposed method. Findings demonstrated hydrogen sulfide and methane reductions of about 96.01% and 91.49%, respectively, by the combined addition of NaOH and nitrite. The consumption of NaNO₂ decreased by 42.90%, and the consumption rate of NaOH also showed a downward trend. Compared with a single application of NaNO₂, the C/N ratio of wastewater was increased to about 0.61 mg COD/mg N. The greenhouse effect of intermediate N₂O and residual methane was about 48.80 gCO₂/m³, which is far lower than that of methane without control (260 gCO₂/m³). Biofilm was destroyed to prevent it from entering the sewage by the chemical additives, which reduced the biomass and inhibited the recovery of biofilm activity to prolong the control time. The sulfide production rate and sulfate reduction rate were reduced by 92.32% and 85.28%, respectively. Compared with conventional control methods, the cost of this new method was only 3.92 × 10⁻³ $/m³, which is potentially a cost-effective strategy for sulfide and methane control in gravity sewers.     

Cloud point extraction of trace cyanide from environmental waters for indirect flame atomic absorption spectrometric determination

A method has been developed for indirect determination of cyanide in environmental waters based on cloud point extraction (CPE), preconcentration and determination by flame atomic absorption spectrometry (FAAS). The method was based on reduction of Cu(II) to Cu(I) in the presence of cyanide and complexation of the produced Cu(I)(CN)₂^? with gallocyanin (GC⁺) as an ion-pairing reagent at pH 4.0, followed by its extraction into polyethyleneglycol mono-p-nonylphenylether (Ponpe 7.5). Selectivity was improved with the use of suitable masking agents. Various factors influencing separation and preconcentration of cyanide have been investigated, and conditions were optimized, allowing determination of cyanide in the range of up to 1.2 mg L^?1 with a detection limit of 0.00045 mg L^?1. The method has been applied to the determination of cyanide in environmental waters, the results being in agreement with those obtained by a reference method.     

Simplified method for the determination of acid-soluble sulfides in marine sediments

A simple, rapid method for the measurement of acid-soluble sulfides from marine sediments, in the range of 0 to 350 g sulfide, was developed. Using the mean of 4 replicates, the maximum sensitivity of the method is ±5.48 g. The method is based on iodometric back titration after the reaction of a standard iodine solution with the sulfide, which is precipitated on paper wicks as zinc, sulfide. The mean coefficient of variation, based on raw titration data, is 0.71% for aliquots from field samples, 0.41% for standards, and 0.21% for blanks. The method is used to compare zinc acetate-fixed subsamples, one group having been stored for 1 month in a refrigerator at 5°C and the other having been analyzed immediately after collection. No significant differences in sulfide content between subsamples, at the 95% confidence level, were noted.     

木屑生物膜处理H2S气体研究

采用木屑为载体固定微生物处理含H2S废气．微生物经活性污泥驯化得到．结果表明：木屑为载体固定微生物小需要长时间的挂膜时间．生物滤池启动后的48h内进气浓度迅速提高到641mg／m^3，H2S的去除率达到了100％．实验测定了不同容积负荷下H2S的处理率，当容积负荷为360g(H2S)／(m^3d)时，H2S气体的去除率可以稳定在97．4％以上．最后采用Michaelis-Menten关系式对H2S的去除速率进行了宏观动力学分析，计算得出半饱和因子Ks为242．75mg／m^3，最大表观去除率Vm为833．33g(H2S)／(m^3d)．图5表2参8     

Effect of hydrogen sulfide in comparison to atorvastatin on endothelial damage in cholesterol-fed rabbits

Hydrogen sulfide (H₂S) is an endogenous gaseous molecule, functioning as a physiological regulator. This study aimed to investigate the role of H₂S in atherosclerosis. Rabbits receiving high cholesterol were given atorvastatin (10 mg/kg/day, orally) or sodium sulfide (1.1 mg/kg/day, intramuscular) 2 weeks after commencement of high-cholesterol diet and continued for 4 weeks. Serum lipid profiles, lipid peroxidation indexed as malondialdehyde, glutathione, superoxide dismutase, the vascular adhesion molecule-1, and aortic vascular endothelial growth factor were determined. Rabbits receiving a high-cholesterol diet showed elevated levels of total serum cholesterol, triglycerides, low-density lipoprotein cholesterol, malondialdehyde and vascular adhesion molecule-1, and aortic vascular endothelial growth factor expression and lower levels of high-density lipoprotein cholesterol, glutathione, and superoxide dismutase. Treatment with atorvastatin and sodium sulfide has beneficial effects on serum lipid profile, oxidative damage, vascular adhesion molecule-1, and aortic expression of vascular endothelial growth factor.