Direct quantification of organic acids in aerosols by desorption electrospray ionization mass spectrometry

Desorption electrospray ionization mass spectrometry (DESI-MS) is a novel analytical technique for direct surface analysis under ambient conditions. In this work, we report the first application of DESI-MS to the analysis of organic acids in atmospheric aerosols. We took oxalic and oleic acids as two typical representatives of the particulate organic acids. Experimental parameters for DESI-MS were optimized to enhance the signal intensity. Calibrations for both acids showed great linearity over a concentration range of 5 orders of magnitude with correlation coefficients R²>0.99. The relative standard deviation (RSD) was less than 10% for oxalic acid and within 15% for oleic acid measurement. The detection limits for oxalic acid and oleic acid are about 1 pg mm^?2 with 5–10 s sampling time. Mass concentrations of organic acids in both laboratory-generated biomass burning and ambient aerosols were measured by DESI-MS and the results agree well with the ion chromatography (IC) and GC–MS values. This work demonstrates that DESI-MS is a promising method for rapid quantitative analysis of organic acids in atmospheric aerosols.     

On the Laws and Causes of Socio-economic Territorial Differentiation in Minority Areas in China

On the basis of applying quantitative and qualitative approaches as well as GIS technology, this paper established an index system to make a comprehensive evaluation on socioeconomic development of minority areas in China. The result showed that socio-economic development in minority area presents a series of characteristics that the north is high and the south is low, center-margin pattern is obvious and the areas with middle and lower development indices are distributed centrally and continuously. However, the causes of the socioeconomic characteristics mainly include natural conditions, economic development basic, population cultural quality, regional combination and development conditions of mineral and energy resources, informal institutional factors and distribution of major traffic lines.     

Comparison of manual and automated chambers for field measurements of N2O,CH4, CO2 fluxes from cultivated land

Chamber techniques can easily be applied to field trials with multiple small plots measuring carbon- and nitrogen-trace gas fluxes. Nevertheless, such chamber measurements are usually made weekly and rarely more frequently than once daily. However, automatic chambers do allow flux measurements on sub-daily time scales. It has been hypothesized that sub-daily measurements provide more reliable results, as diurnal variations are captured better compared to manual measurements. To test this hypothesis we compared automatic and manual measurements of N₂O, CO₂ and CH₄ fluxes from tilled and non-tilled plots of a rice–wheat rotation ecosystem over a non-waterlogged period. Our results suggest that both techniques, i.e., either manual or automatic chambers of N₂O and CO₂ emissions resulted in biased fluxes. The manual measurements were adequate to capture either day-to-day or seasonal dynamics of N₂O, CO₂ and CH₄ exchanges, but overestimated the cumulative N₂O and CO₂ emissions by 18% and 31%, respectively. This was due to neglecting temperature-dependent diurnal variations of C and N trace gas fluxes. However, the automatic measurements underestimated the cumulative emissions of N₂O and CO₂ by 22% and 17%, respectively. This underestimation resulted from chamber effects upon soil moisture during rainfall processes. No significant difference was detected between the two methods in CH₄ exchanges over the non-waterlogged soils. The bias of manual chambers may be significant when pronounced diurnal variations occur. The bias of automatic measurements can only be avoided/minimized if chamber positions are frequently changed and/or if chambers are automatically opened during rainfall events. We therefore recommend using automatic chambers together with continuous measurements of soil chamber moisture to allow for soil moisture correction of fluxes or to correct flux estimates as derived by manual chambers for possible diurnal variations.     

über die Notwendigkeit der wirkungsorientierten Analytik in einer umfassenden Wasserforschung

Ohne Zusammenfassung Verantwortliche Herausgeber: Jan Schwarzbauer · Peter Heininger · Evelyn Claus

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剩余污泥超声预处理后水解酸化特性

为探讨剩余污泥超声预处理后的水解酸化特性,考察了0.6 W/mL、5 min和1 W/mL、5 min 2种超声预处理条件下污泥水解酸化过程有机质、氮、磷的释放情况。实验结果表明,2种超声预处理均可促进污泥水解酸化,并且0.6 W/mL比1 W/mL的超声预处理更有利于SCOD的释放、VFAs的产生以及氮和磷的释放;水解酸化初期,超声预处理比未经超声预处理的污泥在有机质、氮、磷释放率上差异非常明显,随着水解酸化的进行,有机质和氮释放率差异仍很明显,而磷释放程度逐渐接近;经0.6 W/mL超声预处理,污泥水解酸化3 d后,SCOD释放率、VFAs浓度、TN释放率和NH4+-N释放率分别是未经处理污泥的1.85、2.63、1.85和1.41倍,而TP和PO43--P释放率较未经处理污泥仅分别多2.44和1.23个百分点。研究表明,控制适宜的声能密度、超声时间和水解酸化进程是超声预处理强化剩余污泥水解酸化效果的关键。     

Changes in the spatial patterns of human appropriation of net primary production (HANPP) in Europe 1990–2006

Understanding patterns, dynamics, and drivers of land use is crucial for improving our ability to cope with sustainability challenges. The human appropriation of net primary production (HANPP) framework provides a set of integrated socio-ecological indicators that quantify how land use alters energy flows in ecosystems via land conversions and biomass harvest. Thus, HANPP enables researchers to systematically and consistently assess the outcome of changes in land cover and land-use intensity across spatio-temporal scales. Yet, fine-scale HANPP assessments are so far missing, an information important to address site-specific ecological implications of land use. Here, we provide such an assessment for Europe at a 1-km scale for the years 1990, 2000, and 2006. The assessment was based on a consistent land-use/biomass flow dataset derived from statistical data, remote sensing maps, and a dynamic global vegetation model. We find that HANPP in Europe amounted to ~43 % of potential productivity, well above the global average of ~25 %, with little variation in the European average since 1990. HANPP was highest in Central Europe and lower in Northern and Southern Europe. At the regional level, distinct changes in land-use intensity were observed, most importantly the decline of cropland areas and yields following the breakdown of socialism in Eastern Europe and the subsequent recovery after 2000, or strong dynamics related to storm events that resulted in massive salvage loggings. In sum, however, these local dynamics cancelled each other out at the aggregate level. We conclude that this finding warrants further research into aspects of the scale-dependency of dynamics and stability of land use.     

生态田处理油田污水的探索与实践

生态田污水处理技术具有低投资、低能耗、低运行费用等诸多优点,结合油田所处的地理位置及实际生产情况,利用生态田天然植物的生物效能,对油田污水处理后用于植被灌溉,并且针对处理过程中存在的问题提出了工艺改造对策措施,最终实现净化污水的目的。     

Does quinone or phenol enrichment of humic substances alter the primary compound from a non-algicidal to an algicidal preparation?

Dissolved organic matter (DOM) has been shown to affect phytoplankton species directly. These interactions largely depend on the origin and molecular size of DOM and are different in prokaryotes and eukaryotes. In a preceding study, however, two humic substance preparations did not adversely affect coccal green algae or cyanobacterial growth even at high concentrations of dissolved organic carbon (DOC). These results contradicted previous findings, showing a clear, negative response of different phototrophs to much lower DOC concentrations. To test whether or not at least defined building blocks of humic substances (HSs) are effective algicidal structures, we enriched two humic preparations with hydroquinone and p-benzoquinone, respectively, and exposed two different green algae, Pseudokirchneriella subcapitata and Monoraphidium braunii, and two cyanobacterial species, Synechocystis sp. and Microcystis aeruginosa, to the unmodified and enriched HSs. As response variables, growth rates in terms of biomass increase, chlorophyll-a content, and photosynthetic yield were measured. The highest concentration (4.17 mM DOC) of the modified HSs clearly inhibited growth; the cyanobacterial species were much more sensitive than the green algal species. However, realistic ecological concentrations did not adversely affect growth. Aerating the exposure solution for 24 h strongly reduced the inhibitory effect of the modified HSs. The algicidal effect was obviously caused by monomers and not by polymerised high molecular weight HSs themselves. Furthermore, the maximum quantum yield (Φ PSII max) was stimulated in the green algal species by low and medium DOC concentrations, but reduced in the cyanobacterial species upon exposure to higher HS concentrations. The quinone- and phenol-enriched HSs only showed algicidal activity at high concentrations of 4.17 mM DOC and lost their effects over time, presumably by oxidation and subsequent polymerisation. This study confirms that the applied humic substances themselves are not effective algicides even if enriched in effective structures.     

金属离子对菌株JY01生长和苯酚降解性能的影响研究

金属可能通过生理和生态两方面对微生物的苯酚降解过程产生重要影响.为了提高芽孢杆菌Bacillus sp.JY01(以下称菌株JY01)的苯酚降解效率,探讨了6种金属离子(Ba2+、Cu2+、Co2+、Fe3、Zn2+、pb2+)对其生长和苯酚降解性能的影响.结果表明,在质量分数为0.001％～0.050％时,Cu2+、Zn2+、Co2、Fe3+、Ba2+、pb2+对菌株JY01的生长和苯酚降解均有抑制作用,并且抑制作用总体随金属离子浓度的升高而增强,当6种金属的质量分数分别达到0.005％时,菌株JY01对苯酚的降解能力为Ba2+ ＜Cu2+ ＜Co2+ ＜Fe3+ ＜Zn2+ ＜pb2+;金属离子通过影响菌株JY01的生长状况来影响其苯酚降解性能;很多金属离子对菌株JY01生长有明显抑制作用,因此在实际生物处理含苯酚废水时,要考虑废水中金属离子对降解菌生长状况的影响.     

一株产絮酵母菌废菌体对Cd~（2＋）的吸附特性

将一株产絮酵母菌（编号B-02号）发酵后的废菌体制成生物吸附剂,研究该生物吸附剂对废水中Cd2＋的生物吸附特性。结果表明：（1）pH值对Cd2＋会产生较大的影响,偏酸性（pH=4～6）条件利于吸附;该吸附剂对Cd2＋吸附速率较快,8～10 min就可达到吸附平衡;（2）吸附剂的吸附动力学符合二级动力学模型,吸附Cd2＋的实验数据对Langmuir等温式的拟合情况良好,吸附剂吸附Cd2＋的最大吸附量为70.752 mg/g。用0.5 mol/L HNO3对吸附Cd2＋的酵母菌进行解吸,解吸率可达89.7%。