雨水中NO^—2和NO^—3的动态涂渍离子对色变分离测定

采用反相离子对色谱法一些外光度检测测定NO^2和NO^-3，对影响分离测定的诸因素进行了研究，建立了测定雨水中这2种组分的最佳色谱条件，结果表明该方法快速，灵敏，线性宽。     

南通市降水中SO4^2—,NO3^—的分析

通过对南通城区１９９１－１９９５年降水中ＳＯ４与ＮＯ３离子浓度统计分析，了解了同一监测点上不同污染物之间的相关性和变化规律。     

分析器具洗涤方法对离子色谱法测定SO4^2—和Cl^—的影响分析

离子色谱法测定SO4^2-和Cl^-具有操作简单、灵敏度高的特点，但是SO4^2-和Cl^在自然界中分布面广，既便是在蒸馏水中，也有微量检出。监测中如果使用常规的洗涤方法对各种分析器具进行清洗，SO4^2-和Cl^-极易残留于器具上。本文对常规洗涤各种分析器具残留的SO4^2-和Cl^-进行测定，以确定在环境样品监测分析中，常规洗涤法在各种分析器具具的残留的SO4^2-和Cl^-对离子色谱法测定SO4^2-和Cl^-的结果的影响。     

雨水中NO_2~-和NO_3~-的动态涂渍离子对色谱分离测定

采用反相离子对色谱法—紫外光度检测测定NO-2 和NO-3 ,对影响分离测定的诸因素进行了研究 ,建立了测定雨水中这 2种组分的最佳色谱条件。结果表明该方法快速、灵敏、线性宽。     

雨水中NO2-和NO3-的动态涂渍离子对色谱分离测定

采用反相离子对色谱法-紫外光度检测测定NO2-和NO3-，对影响分离测定的诸因素进行了研究，建立了测定雨水中这2种组分的最佳色谱条件。结果表明该方法快速、灵敏、线性宽。     

水和废水中简单氰化物,易释放氢氰酸的氰化物和总氰化物的测定—微库仑碘量

报告了ＣＮ浓度在０．０１～１５００ｍｇ／Ｌ范围内用微库仑碘量法测定水与废水中简单氰化物，易释放氢氰酸的氰化物及总氰化物ＣＮ的方法，简单氰化物ＣＮ勿需预蒸馏，毕分离与测定于一次进样，列表比较了其它二种氰化物的分离与测定时，本法ＧＢ法，ＩＳＯ法，ＡＳＴＭ法及原苏标准方法在试剂耗量，能耗，时耗等方面的优劣，简易的自动补液，成功地使本法测２００～３００个水样不更换电解液，用本法与ＧＢ法对各种类型水样中氰化     

北京市燕山地区大气颗粒物中NO3^—和SO^2—4浓度变化规律及其与O3的关系

用ＫＢ－１２０型大气颗粒气采样品采集，离子色谱法分析其中水溶性无机阴离子组分。结果表明，北京市燕山石油化工区大气颗粒物中ＮＯ＾－３和ＳＯ＾２－４浓度随季节变化显著。     

离子色谱同时测定脱硫脱硝副产物中SO_3~(2-)、SO_4~(2-)、NO_2~-、NO_3~-方法研究

使用离子色谱测脱硫脱硝副产物中的亚硫酸根、硫酸根、亚硝酸根、硝酸根4种离子,研究通过加甲醛抑制亚硫酸根的氧化,研究甲醛对4种离子,以及4种离子之间在测定时是否会相互影响。结果发现:硫酸根、亚硝酸根、硝酸根3种离子比较稳定,而SO_3~(2-)易被氧化。发现采用甲醛作为抗氧化剂可以较好地抑制SO_3~(2-)的氧化;用1 mmol/L的KOH作为淋洗液时,甲醛的质量分数可选为0.05%,若甲醛浓度过高,除影响色谱柱寿命外,SO_3~(2-)的出峰面积也会变小。甲醛的加入不影响亚硝酸根和硝酸根的出峰。亚硫酸根、硫酸根、亚硝酸根、硝酸根同时测定过程中相互干扰不大,4种离子的线性关系较好。采用甲醛做抗氧化剂时,不应采用Na_2CO_3等弱碱溶液作为淋洗液。总之,通过加入适量的甲醛,离子色谱法可以准确同时测定脱硫脱硝产物的亚硫酸根、硫酸根、亚硝酸根、硝酸根4种离子。     

O3/H2O2法降解甲基叔丁基醚（MTBE）的试验研究

采用自制鼓泡反应器对臭氧/双氧水(O3/H2O2)降解水中甲基叔丁基醚(MTBE)进行了试验研究,考察了进气(含O3)流量、H2O2 投加量、MTBE初始浓度、pH、温度等因素对MTBE降解的影响.结果表明,在MTBE初始浓度为10 mg·L-1,气体流量为0.5 L·min-1,温度293K, pH=6.5, H2O2 添加量为2.4mg·L1 条件下,反应30 min后, MTBE去除率可达75.5%, COD去除率为68.0%.降解得到的中间产物主要有叔丁基甲酯(TBF)、叔丁醇(TBA)、乙酸甲酯(MA)和丙酮(AC)等,据此探讨了O3/H2O2氧化MTBE的可能反应机理和降解途径.     

An estimate of the conversion rates of SO_2 to SO_4~(2-)- and NO_2 to HNO_(3+) NO_3~- for the evaluation air pollution in Beijing

The conversion rates of SO2 to SO42- and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of SO2; The conversion rates have a diurnal variation in a day. On the average, the rate of SO2 is estimated to be 4.7% h-1 during the daytime and 3.4% h-1 during the nighttime. Similarly, the rate of NO2 is estimated to be 17.2% h-1 and 12% h-1 respectively.     

A monitoring-modeling approach to SO42 − and NO3− secondary conversion ratio estimation during haze periods in Beijing, China

SO_4~(2-) and NO_3~- are important chemical components of fine particulate matter(PM_(2.5)),especially during haze periods.This study selected two haze episodes in Beijing,China with similar meteorological conditions.A monitoring-modeling approach was developed to estimate the secondary conversion ratios of sulfur and nitrogen based on monitored and simulated concentrations.Measurements showed that in Episode 1(24th–25th October,2014),the concentrations(proportions)of SO_4~(2-) and NO_3~- reached 35.1μg/m~3(14.9%) and 55.0μg/m~3(22.9%),while they reached 14.4μg/m~3(9.3%) and 59.1μg/m~3(38.1%)in Episode 2(26th–27th October,2017).A modeling system was applied to apportion Beijing's SO_4~(2-) and NO_3~- in primary and secondary SO_4~(2-)/NO_3~- emitted from local and regional sources.Thus,secondary conversion contributions considering the local and regional level were defined.The former primarily focused on Beijing atmospheric oxidation ability and the latter mainly considered the existence form of Beijing SO_4~(2-)/NO_3~- under the regional transport impacts.Finally,secondary oxidation ratios were estimated through combining secondary conversion contribution coefficients for simulated and monitored concentrations.At regional level,sulfur oxidation ratios in polluted(clean)days during two sampling periods were0.57–0.72(0.07–0.52)and 0.74–0.80(0.08–0.61),nitrogen oxidation ratios were 0.20–0.29(0.05–0.15)and 0.34–0.38(0.02–0.29),indicating that atmospheric oxidation was enhanced when considering regional transport through 2014–2017.At the local level,sulfur oxidation ratios were 0.66–0.71(0.04–0.48)in haze(clean)days,while nitrogen oxidation ratios were0.16–0.29(0.02–0.16).The atmospheric oxidation ability markedly increased in PM_(2.5)pollution days,but changed only slightly between the two periods.     

异戊二烯与O3反应体系中有机氢过氧化物和H2O2的产率研究

用双通道Ｈ２Ｏ２分析系统研究了室温条件下异戊二烯与Ｏ３气相暗反应体系中机氢过氧化物和Ｈ２Ｏ２的产率,３次实验测得有机氢过氧化物的产率分别为３．８％和４．３％和３．９％,平均为４．０％;Ｈ２Ｏ２的产率分别为２．２％、１．６％和１．８％,平均为１．９％,探讨了异茂二烯与Ｏ３反应体系中有机氢过氧化物和Ｈ２Ｏ２的生成机理。     

UV－H2O2法去除亚硝酸盐氮和氨氮的研究

用H₂O₂、紫外光(UV)辐射促进H₂O₂方法考察了水中NO-₂和NH+₄的氧化,结果表明,NO-O₂能被H₂O₂有效地氧化,而NH+₄不能被NO-₂和H₂O₂氧化,但UV辐射均有助于反应进行,使反应速率加快。      

Comparison of degradation reactions of Acid Yellow 61 in both oxidation processes of H2O2/UV and O3

ＩｎｔｒｏｄｕｃｔｉｏｎＣｏｌｏｒｓｕｂｓｔａｎｃｅｓｉｎｄｙｅｉｎｇｅｆｆｌｕｅｎｔｓｎｏｒｍａｌｌｙｃａｕｓｅｃｅｒｔａｉｎｄｉｆｆｉｃｕｌｔｉｅｓｉｎｔｒａｄｉｔｉｏｎａｌｂｉｏｌｏｇｉｃａｌｔｒｅａｔｍｅｎｔｐｒｏｃｅｓｓｅｓｄｕｅｔｏｔｈｅｄｙｅｍｏｌｅｃｕｌｅｓａｒｅｈｉｇｈｌｙｓｔｒｕｃｔｕｒｅｄｐｏｌｙｍｅｒｓａｎｄｔｈｅｉｒｔｏｘｉｃｉｔｙ (Ｈａｍｚａ ,1980 ;Ｇｉｎｏｃｃｈｉｎｉｏ ,1984 ;ＭａＫａｙ ,1980 ) .Ｉｔｉｓｎｅｃｅｓｓａｒｙｔｏｉｍｐｒｏｖｅｔｈｅｔｒｅａｔｍｅｎｔｅ…     

γ辐照和H2O2联合作用下五氯酚(PCP)的降解

研究了水溶液中的五氯酚(PCP)在γ辐照和过氧化氢(H2O2)联合作用下的降解.PCP的初始浓度为27.7 mg·L-1,外加H2O2的初始浓度为0、50和100 mg·L-1.结果表明,PCP在不同条件下的辐照降解符合准一级动力学方程.当外加H2O2的初始浓度在0～100 mg·L-1时,PCP的去除率、矿化率和脱氯...     

弱碱性阴离子交换纤维吸附H2S和CO2混合气体的研究

主要研究了弱碱性阴离子交换纤维对高浓度的Ｈ２Ｓ、ＣＯ２混合气体的吸附性能，考察了各种因素对吸附的影响规律，为今后进一步的研究打下了一定的基础。     

Fe2O3纳米棒的制备及其H2S气敏性能研究

为快速检测H2S泄漏,以一步水热法制备的Fe2O3纳米棒为基础,制备了H2S气体传感器。研究表明,该传感器在300℃工作温度下对10μmol/mol的H2S的灵敏度为2左右,响应时间为12s左右,恢复时间约4s。而且该传感器具有优异的稳定性和选择性,对CH4、CO等多种气体响应较差,适合用于长时间快速检测H2S气体的泄漏。     

Catalytic performance of Fe3O4-CoO/Al2O3 catalyst in ozonation of 2-(2,4-dichlorophenoxy)propionic acid, nitrobenzene and oxalic acid in water

Fe3O4-CoO/Al2O3 catalyst was prepared by incipient wetness impregnation using Fe(NO3) 3·9H2O and Co(NO3) 2·6H2O as the precursors,and its catalytic performance was investigated in ozonation of 2-(2,4-dichlorophenoxy) propionic acid(2,4-DP) ,nitrobenzene and oxalic acid.The experimental results indicated that Fe3O4-CoO/Al2O3 catalyst enabled an interesting improvement of ozonation eciency during the degradation of each organic pollutant,and the Fe3O4-CoO/Al2O3 catalytic ozonation system followed a radical-type mechanism.The kinetics of ozonation alone and Fe3O4-CoO/Al2O3 catalytic ozonation of three organic pollutants in aqueous solution were discussed under the mere consideration of direct ozone reaction and OH radical reaction to well investigate its performance.In the catalytic ozonation of 2,4-DP,the apparent reaction rate constants(k) were determined to be 1.456×10-2 min-1 for ozonation alone and 4.740×10-2 min-1 for O3/Fe3O4-CoO/Al2O3.And O3/Fe3O4-CoO/Al2O3 had a larger Rct(6.614×10-9) calculated by the relative method than O3 did(1.800×10-9) ,showing O3/Fe3O4-CoO/Al2O3 generated more hydroxyl radical.Similar results were also obtained in the catalytic ozonation of nitrobenzene and oxalic acid.The above results demonstrated that the catalytic performance of Fe3O4-CoO/Al2O3 in ozonation of studied organic substance was universal to a certain degree.