不同温度下应用比值控制实现连续流好氧颗粒污泥短程硝化

在连续流反应器中接种成熟好氧颗粒污泥（AGS）处理低氨氮污水,通过控制溶解氧（DO）和出水氨氮（NH₄⁺-N）的浓度,研究了控制DO/NH₄⁺-N（R值）实现连续流好氧颗粒污泥系统短程硝化的可行性和不同温度（30、20、10℃）条件下实现短程硝化系统对R值的需求.结果表明,通过比值控制,连续流好氧颗粒污泥系统可以快速实现短程硝化;在30、20、10℃条件下,系统实现短程硝化所需要的R值分别为0.50（±0.05）、0.35（±0.03）和0.20（±0.02）.因此可知,温度越低,系统实现短程硝化所需要的氧抑制越强.采用荧光原位杂交（fluorescence in situ hybridization,FISH）实验表明,通过比值控制,氨氧化菌（AOB）得到一定的富集,而亚硝酸盐氧化菌（NOB）的相对数量逐渐减少.基于比值控制和污水水质的特点,选择短程硝化的方式有所不同,低氨氮废水选择半量亚硝化,而高氨氮污水则选择全量亚硝化.     

Evaluating Controlling Factors to Ali/(Ca + Mg) Molar Ratio in Acidic Soil Water, Southern and Southwestern China: Multivariate Approach

Al_i/(Ca + Mg) molar ratio in soil water has been used as an indicator to the effects of acid deposition on terrestrial ecosystems. However, the main factors controlling this ratio have not been well documented in southern and southwestern China. In this study, we presented the variation in inorganic aluminum (Al_i) and Al_i/(Ca + Mg) molar ratio in different sites and soil horizons based on two to three years monitoring data, and evaluated the main factors controlling Al_i/(Ca + Mg) molar ratio using principle component analysis (PCA) and partial least square (PLS) regression. Monitoring data showed although Al_i/(Ca + Mg) molar ratios in most soil water were lower than assumed critical 1.0, higher molar ratios were found in some soil water at TSP and LXH site. Besides acid loading, both soil properties and soil water chemistry affected the value of Al_i/(Ca + Mg) molar ratio in soil water. Partial least square (PLS) indicated that they had different relative importance in different soil horizons. In A-horizon, soil aluminum saturation (AlS) had higher influence on Al_i/(Ca + Mg) molar ratio than soil water chemistry did; higher soil aluminum saturation (AlS) led to higher Al_i/(Ca + Mg) molar ratio in soil water. In the deeper horizons (i.e., B₁-, B₂- and BC-horizon), inorganic aluminum (Al_i) in soil water had more and more important role in regulating Al_i/(Ca + Mg) molar ratio. On regional scale, soil aluminum saturation (AlS) as well as cation exchange capacity (CEC) was the dominant factor controlling Al_i/(Ca + Mg) molar ratio. This should be paid enough attention on when making regional acid rain control policy in China.     

大体积进样技术结合同位素稀释法测定地表水中多环芳烃的研究

采用C18固相萃取柱预处理水样,由于固相萃取柱的选择吸附性,净化了样品的基质;同液-液萃取相比,固相萃取柱和硅胶小柱的双重净化,更适合大体积进样。萘、苊、菲、屈艹的氘代化合物作为同位素稀释剂,由于待测分析物与同位素稀释剂物理化学的相似性,其在固相萃取柱的保留行为和色谱运行行为都有基本一致性。同一般内标法相比,同位素稀释法具有较高的回收率。大体积进样由于进样绝对量的增加,降低了检出限。方法检出限0.05～0.1ng/L,回收率范围90%～110%。     

米氏凯伦藻在三种无机氮源的生长情况

米氏凯伦藻引发的赤潮危害鱼类和无脊椎动物,给养殖业带来严重的经济损失,研究其营养生理生态,对掌握该藻形成赤潮的规律有着重要的意义。采用一次培养的实验方法研究了米氏凯伦藻(Karenia mikimotoi Hansen)在三种无机氮源不同氮磷浓度比(cN/cP)下的生长情况。结果表明:在分别以氯化铵、硝酸钠和亚硝酸钠为氮源时,米氏凯伦藻生长的最适cN/cP比分别为32、32和100。米氏凯伦藻对氯化铵的利用效率相对低于硝酸钠和亚硝酸钠,以氯化铵为氮源该藻生长缓慢,细胞密度低;而分别以硝酸钠和亚硝酸钠为氮源时该藻生长情况较好,可较长时间维持高的细胞密度。     

Offspring sex ratio in relation to parental structural size and body condition in the long-lived wandering albatross (<Emphasis Type="Italic">Diomedea exulans</Emphasis>)

Sex ratio theory is one of the most controversial topics in evolutionary ecology. Many deviations from an equal production of males and females are reported in the literature, but few patterns appear to hold across species or populations. There is clearly a need to identify fitness effects of sex ratio variation. We studied this aspect in a population of a long-lived seabird, the wandering albatross (Diomedea exulans), using molecular sex-identification techniques. We report that parental traits affect both (1) fledgling traits in a sex-dependent way and (2) chick sex: Sons are overproduced when likely to be large at fledging and, to a lesser extent, daughters are overproduced when likely to be in good body condition at fledging. Because for the same population, a previous study reported that post-fledging survival was positively affected by size in males and by body condition in females, our results suggest that wandering albatrosses manipulate offspring sex to increase post-fledging survival.     

在线固相萃取-液相色谱串联质谱法测定污水厂尾水中6种酸性药物

建立了大体积在线固相萃取-液相色谱串联质谱(Online-SPE-LC-MS)检测污水厂尾水中6种酸性药物的方法.10 mL水样采用0.45μm微孔滤膜过滤后经自动进样器直接在线上样,经Atlantis T3柱(100 mm×4.6 mm×3μm)富集,Atlantis T3柱(100 mm×2.1 mm×2.6μm)...     

江苏省部分地区农田表土多环芳烃含量比较及来源分析

采集江苏省兴化市、吴江市、宜兴市、南京市六合区的农田表层(0-15 cm)土壤样品共30个,用高效液相色谱测定土壤中16种多环芳烃(PAHs)含量.结果表明,土壤中∑PAHs含量介于45.6～2 286.8 μg·kg-1之间.兴化市、吴江市土壤中PAHs平均含量分别为1 370.3、801.1 μg·kg-1,污染严重;宜兴市、南京市六合区土壤中PAHs平均含量分别为210.8、126.7 μg·kg-1,为轻微污染或无污染.根据不同环数PAHs相对丰度和菲(Phe)/蒽(Ant)、荧蒽(Fla)/芘(Pyr)比值以及对4地的实际调查,发现调查区土壤样品中PAHs来源复杂,主要有机动车尾气排放,煤、草和木材的燃烧以及石油泄漏等.     

基于液气比的湿法脱硫系统的运行优化研究

石灰石-石膏湿法烟气脱硫是一种比较成熟、脱硫效率较高的脱硫技术。阐述了这种方法的化学基础和过程动力学,研究了影响烟气脱硫效率的主要因素,并讨论了液气比对提高脱硫效率和降低成本的影响。通过对某公司脱硫系统的优化调整,系统运行稳定,节能效果明显。根据机组负荷控制液气比在11 L/m3左右,脱硫系统的安全性和经济性均可保证,并有广泛地推广空间。     

Influence of the composition of the initial mixtures on the chemical composition,physicochemical properties and humic-like substances content of composts

The influence of the proportion of C- and N-rich raw materials (initial C/N ratio) and bulking agent on the chemical functional groups composition, humic-like substances (HS-like) content and physicochemical properties of composts was assessed. To achieve these goals, seven initial mixtures (BA1–6 and C1) of dog food (N-rich raw material) were composted with wheat flour (C-rich raw material). Composts were analyzed in terms of chemical functional groups, physicochemical, maturity and stability parameters.The C-rich raw material favored the formation of oxidized organic matter (OM) during the composting process, as suggested by the variation of the ratios of the peaks intensity of FT-IR spectra, corresponding to a decrease of the polysaccharides and an increase of aromatic and carboxyl-containing compounds. However, although with high proportion of C-rich raw material, mixtures with low initial C/N seems to have favored the accumulation of partially oxidized OM, which may have contributed to high electrical conductivity values in the final composts. Therefore, although favoring the partial transformation of OM into stabilized HS-like, initial mixtures with high proportion of C-rich raw material but with low initial C/N led to unstable composts.On the other hand, as long as a high percentage of bulking agent was used to promote the structure of biomass and consequently improve of the aeration conditions, low initial C/N was not a limiting factor of OM oxidation into extractable stabilized humic-like acids.     

Standardizing the Methodology of Sperm Cell Test with Paracentrotus Lividus

The sperm cell toxicity test with Paracentrotus lividus is widely used in Italy to assess the quality of complex aqueous matrices, but at present there is a shortage of standardized methodologies for the bioassay performance. In this work several critical points were considered, in order to verify the reliability of this bioassay and to improve its standardization.In particular, we have studied the differences in EC50 values at different sperm: egg ratios and with different quantities of gametes; the influence of sperm and eggs on fertilization rate and the influence of different recipients materials (plastic or glass). At the same time, it was evaluated if the obtained EC50 values were in accordance with those reported in literature.Experiments performed yielded EC50 values for copper ranging from 16.54 μ g/l to 69.59 μ g/l, with a total mean value ± SD of 39.79 μ g/l ± 11.17. These data fit with those found in literature for other echinoid species. According to the same authors, poor fertilization was probably due to the effects on sperm and not on eggs, and moreover the linear regression analysis performed on each experiment suggested that the best amount of eggs to use in the test was 1000.Results from the comparison between the performance of the test in plastic or glass tubes showed an higher success in fertilization rate using borosilicate glass tubes.