关于铜、锌和某些金属离子对苯并(a)芘致突变性和代谢的影响

本文通过探讨金属离子对苯并(a)芘致突变性和代谢的影响,初步发现,铜和锌离子能显著地抑制微粒体芳烃羟化酶、环氧化物水化酶的活性,抑制苯并(a)芘代谢和抑制苯并(a)芘及焦炉尾气飘尘提取物的致突变性。实验表明,铜和锌离子可能通过调节那些催化苯并(a)芘和焦炉尾气飘尘提取物,转变成亲电性中间产物的代谢酶系,起到抑制苯并(a)芘等有关环境污染物的致突变性和致癌性的作用。     

二氧化氯在印染废水处理中的应用

用二氧化氯处理印染废水，脱色率和ＣＯＤ去除率分别达到９７．５％和８０．３％，处理后的废水指标完全符合国家排放标准，同时设备使用安全可靠，运行成本低。     

城市污水中有色物质的分离鉴定

本研究采用二氯甲烷分步萃取,硅胶柱净化和预分离、高效液相色谱结合薄层色谱的定性方法,从不同时期采集的城市污水处理厂二级出水中分离鉴定出七种染料,并对鉴定出的染料进行了定量分析。     

流动注射—化学发光法测定大气二氧化硫

本文对大气二氧化硫的流动注射—化学发光法测定进行了研究.基于鲁米诺—碘—二氧化硫无机偶合化学发光反应,建立了测定大气二氧化硫的新方法.采用了流动注射气体扩散在线分离技术,使得经典的化学发光测定的选择性大大提高.对鲁米诺—碘这一化学发光体系有很强催化作用的金属离子及其它酸化后不挥发的物质均不影响本体系的测定.方法具有简单、快速、选择性好的特点.已用于大气环境监测分析,结果较满意.     

工业园区能量梯级利用节能减排效益分析及其对城市空气质量影响评估

工业园区由于资源能源消耗和污染排放总量大,能量梯级利用水平普遍较低,在我国推进生态文明建设的过程中受到了重点关注.本研究以河南省一个典型的高能耗工业园区（永城经济技术开发区）为研究对象,对能量梯级利用措施带来的节能效果和大气污染物减排效益进行了定量的研究,并且结合CALPUFF模型分析园区能量梯级利用措施对周边城市大气环境质量的影响.结果表明：①通过应用能量梯级利用措施,有效地提高了能源的使用效率,并减少了SO₂、NO_x以及颗粒物等主要大气污染物的排放量.园区12条能量梯级利用链条的节能总量为10000 TJ, SO₂和NO_x排放量分别减少为611 t和1407 t, PM₁₀ 和PM_2.5分别减少为82 t和45 t.②CALPUFF模拟结果显示园区采用能量梯级利用措施在一定程度上改善了城市大气环境的空气质量.永城市2017年4种污染物的最大1 h平均浓度在有能量梯级利用措施情景（S2）下和无能量梯级利用情景（S1）相比均有所降低,其中NO_x降幅最为明显,在春秋两季为70 μg·m^-3左右.     

Effects of road dust on the growth characteristics of Sophora japonica L. seedlings

Road dust is one of the most common pollutants and causes a series of negative effects on plant physiology. Dust's impacts on plants can be regarded as a combination of load,composition and grain size impacts on plants; however, there is a lack of integrated dust effect studies involving these three aspects. In our study, Sophora japonica seedlings were artificially dusted with road dust collected from the road surface of Beijing so that we could study the impacts of this dust on nitrogen/carbon allocation, biomass allocation and photosynthetic pigments from the three aspects of composition, load and grain size. The results showed that the growth characteristics of S. japonica seedlings were mostly influenced by dust composition and load. Leaf N, root–shoot ratio and chlorophyll a/b were significantly affected by dust composition and load; leaf C/N, shoot biomass, total chlorophyll and carotenoid were significantly affected by dust load; stem N and stem C/N were significantly affected by dust composition; while the dust grain size alone did not affect any of the growth characteristics. Road dust did influence the growth characteristics more extensively than loam. Therefore, a higher dust load could increase the differences between road dust and loam treatments. The elements in dust are well correlated to the shoot N, shoot C/N, and root–shoot ratio of S. japonica seedlings. This knowledge could benefit the management of urban green spaces.     

Gaseous emissions from compressed natural gas buses in urban road and highway tests in China

The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas(CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0–10 km/hr were increased to 10–20 km/hr, the CO_2, CO, nitrogen oxide(NO_x), and total hydrocarbon(THC) emission factors decreased by(71.6 ± 4.3)%,(65.6 ± 9.5)%,(64.9 ± 9.2)% and(67.8 ± 0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards(Euro Ⅳ) did not have lower emission factors than the Chongqing coaches with Euro Ⅱ emission standards. Both the higher emission factors at 0–10 km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO_2 and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most(by 83.2%), followed by the THC emission factors, which decreased by 67.1%.     

Promoting catalytic ozonation of phenol over graphene through nitrogenation and Co3O4 compositing

Catalytic ozonation is progressively becoming an attractive technique for quick water purification but efficient and stable catalysts remains elusive. Here we solvothermally synthesized highly-dispersed Co₃O₄ nanocrystals over microscale nitrogen-doping graphene (NG) nanosheets and tested it as a synthetic catalyst in the ozonation of phenol in aqueous solutions. Transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectra and X-ray photoelectron spectroscopy were used to determine its morphology, crystallinity, elemental composition and molecular bonds, respectively. The comparative experiments confirmed the highest catalytic activity and oxidation degree (AOSC) of Co₃O₄/NG among four nanocomposites (G, NG, Co₃O₄/G, and Co₃O₄/NG). Co₃O₄/NG also has exhibited the highest degradation rate: complete conversion of a near-saturated concentration of phenol (941.1 mg/L) was achieved within 30 min under ambient conditions with only a small dosage of Co₃O₄/NG (50 mg/L) and ozone (4 mg/L, flow rate: 0.5 L/min). It also resulted in 34.6% chemical oxygen demand (COD_Cr) and 24.2% total organic carbon (TOC) reduction. In this work, graphene nanosheets not only functioned as a support for Co₃O₄ nanocrystals but also functioned as a co-catalyst for the enhancement in phenol removal efficiency. The surface nitridation and Co₃O₄ modification treatment further improved the removal rate of the phenol pollutants and brought in the higher oxidation degree. Our finding may open new perspectives for pursuing exceptional activity for catalytic ozonation reaction.     

Gamma irradiation of 2-mercaptobenzothiazole aqueous solution in the presence of persulfate

Recently, water treatment by ionizing radiation has gained increasing attention as a powerful technology for the destruction of refractory pollutants. 2-Mercaptobenzothiazole(MBT) is known as a widespread, toxic and poorly biodegradable pollutant. This paper studied the gamma irradiation of aqueous solutions of MBT. Moreover, the effect of the addition of persulfate(S2O82-) on the radiolytic destruction of MBT was investigated. The main transformation products of the studied compound were detected and the sequence of occurrence of the products was described. The change of biodegradability of MBT solution was also observed. The main results obtained in this study indicated that gamma radiation was effective for removing MBT in aqueous solution. Persulfate addition, which induced the formation of reactive sulfate radicals(SO4-U), greatly enhanced the degradation of MBT. Benzothiazole was identified as the first radiation product, followed by 2-hydroxybenzothiazole. Decomposition of MBT started with the oxidation of –SH groups to sulfate ions. Possible pathways for MBT decomposition by gamma irradiation were proposed. The BOD/COD ratios of MBT samples were increased after radiation,indicating the improvement of biodegradability and reduction of toxicity.     

沈阳市冬季一次典型大气污染过程特征和成因分析

2013年11月18日~25日沈阳地区出现一次典型空气污染过程。采用单颗粒气溶胶质谱仪(SPAMS),并结合气象条件分析了该次污染的成因和细颗粒物的污染特征。结果表明,不利于污染物扩散的气象条件是重污染发生的主要原因,低空排放的积累可能是造成这次污染的又一重要原因。从细颗粒物成分上看,污染过程中有机碳颗粒占比明显增加,有机物污染较为严重,颗粒物间混合加剧;从来源上看,机动车尾气、工业排放和燃煤的占比较高。