长江中游宜昌江段鱼卵时空分布特征研究

为了解长江中游宜昌江段鱼类早期资源现状,并探究漂流性鱼卵空间分布特征,于2018～2019年5～7月在长江中游宜昌江段进行了鱼类早期资源调查,同时对采集到的漂流性鱼卵进行空间分布差异性分析.结果 显示,调查期间共采集鱼卵15 963粒,通过分子生物学方法共鉴定出漂流性鱼卵24种,隶属于1目3科,鱼卵优势种为鲢(Hypophthalmichthys molitrix),占总量的32.94％,其次是飘鱼(Pseudolaubuca sinensis)和草鱼(Ctenopharyngodon idellus),分别占30.80％、12.65％.2018年和2019年平均鱼卵密度分别为5.61±9.72ind./100 m3,9.80±16.09 ind./100 m3,不同种类鱼卵主要出现的时间也具有明显差异.差异性分析结果显示,宜昌江段鱼卵密度在空间分布上有显著差异(P＜0.05),水平分布特征表现为江心(2018年为7.54±20.04ind./100m3, 2019年为13.15±25.49 ind./100 m3)＞南岸(2018年为6.20±7.92 ind./100 m3,2019年为9.25±14.12 ind./100 m3)＞北岸(2018年为3.07±4.71 ind./100 m3,2019年为7.00±11.65 ind./100 m3),垂直分布特征表现为中下层高于表层.该研究中获取的鱼卵在河流中的分布特征可为宜昌产卵场定位和产卵规模估算等提供数据支撑.     

多功能膨胀渗透仪的研制及压实膨润土的渗透性试验

报道多功能膨胀渗透仪的研制及压实膨润土的渗透测试结果。该装置可用于土壤的固结、渗透、膨胀等实验,具有一物多用的特点,特别适合于难渗透的高压实膨润的研究。     

变电站多氯联苯污染源的治理

本文介绍典型的秦安变电站PCB治理情况,建立了一套土壤和空气中PCB残留量的测定方法,完成了该电站内外环境样品中PCB残留量的测定,对污染状况作了评价,设计了相应的治理方案,完成治理一年后的跟踪监测结果证实,污染基本消除,环境得到改善,该方案方法简便,适合我国国情。     

多氯联苯焚烧处置时烟灰中的二噁瑛

专门用于销毁含多氯联苯（ＰＣＢｓ）固体废弃物的中试焚烧炉,焚烧排放物中含有微量剧毒二（ＰＣＤＤ／ＦＳ）．应用同位素稀释ＨＲＧＣ／ＨＲＭＳ方法测定了烟灰中的ＰＣＤＤ／Ｆｓ含量,以１７种有毒同族体的含量可计算出样品的２,３,７,８－ＴＣＤＤ毒性当量为４７．２ｎｇ／ｇ。     

Estrogenicity of pyrethroid insecticide metabolites

There is concern that insecticides are able to mimic the action of 17beta-estradiol by interaction with the human estrogen receptor. Pyrethroids are commonly used insecticides and several have been assessed for potential endocrine disrupting activity by various methods. It has been noted that some metabolites of pyrethroids, in particular, permethrin and cypermethrin, have chemical structures that are more likely to interact with the cellular estrogen receptor than the parent pyrethroid. For this study permethrin and cypermethrin metabolites 3-(4-hydroxy-3-phenoxy)benzyl alcohol, 3-(4-hydroxy-3-phenoxy)benzoic acid, and N-3-(phenoxybenzoyl)glycine were synthesised, and together with the commercially available 3-phenoxybenzyl alcohol, 3-phenoxybenzaldehyde, and 3-phenoxybenzoic acid, were studied in a recombinant yeast assay expressing human estrogen receptors (YES). Three metabolites, 3-phenoxybenzyl alcohol, 3-(4-hydroxy-3-phenoxy)benzyl alcohol, and 3-phenoxybenzaldehyde, showed estrogenic activity of approximately 10(5) less than that of 17beta-estradiol. No activity was observed in the yeast assay for 3-phenoxybenzoic acid, 3-(4-hydroxy-3-phenoxy)benzoic acid, and N-3-(phenoxybenzoyl)glycine. The results from this study show that pyrethroid metabolites are capable of interacting with the human estrogen receptor, and so might present a risk to human health and environmental well being. The impact would be expected to be small, but still add to the overall environmental xenoestrogen load.     

Persistent organic pollutants in Alaskan ringed seal (Phoca hispida) and walrus (Odobenus rosmarus) blubber

Since 1987, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) has collected tissues from 18 marine mammal species. Specimens are archived in the National Institute of Standards and Technology's National Biomonitoring Specimen Bank (NIST-NBSB). AMMTAP has collected blubber, liver and/or kidney specimens from a number of ringed seals (Phoca hispida) from the areas near Nome and Barrow, Alaska and walruses (Odobenus rosmarus) from several locations in the Bering Sea. Thirty-three ringed seal and 15 walrus blubber samples from the NIST-NBSB were analyzed for persistent organic pollutants (POPs). The compounds determined included PCBs (28 congeners or congener groups), DDT and related compounds, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes, dieldrin, and mirex. POP concentrations in ringed seal blubber were significantly higher in Barrow than in Nome when statistically accounting for the interaction of age and gender; HCB, however, was not statistically different between the two locations. Unlike males, POP concentrations and age were not significantly correlated in females probably as a result of lactational loss. POP concentrations in walrus blubber were lower than in ringed seal blubber for SigmaPCBs, chlordanes, and HCHs, but higher for dieldrin and mirex. POP concentrations in ringed seals and walrus from Alaska provide further evidence that the western Arctic tends to have lower or similar POP concentrations compared to the eastern Canadian Arctic.     

黄孢原毛平革菌吸附六价铬的研究

利用黑曲霉常用液体培养基对黄孢原毛平革菌进行扩大培养得到的菌丝球经过冷冻干燥后磨成粒径约为180 μm的粉末用于吸附废水中的Cr(Ⅵ).考察了pH、吸附时间以及预处理方法对吸附的影响.在不同初始浓度条件下,对Cr(Ⅵ)终浓度以及吸附量进行线性转换,发现pH＝2.0条件下Langmuir和Freundlich吸附模型能较好地描述P.chrysosporium菌丝球粉末对Cr(Ⅵ)的吸附.比较吸附前后的傅立叶变换红外光谱图可知,P.chrysosporium吸附Cr(Ⅵ)后,其主要成分和结构保持完整.     

我国中部地区经济增长收敛性分析

运用以人口为权数的Theil指数分析我国中部地区经济σ-收敛发现:1997-2007年中部地区存在较明显的σ-收敛,且省际间的经济差异是中部地区经济σ-收敛的阻碍因素;同时运用Barro和Sala-i-Martin经典模型分析中部地区经济β-收敛,通过加入影响经济增长的动态变量--城市化、工业化等条件发现:中部地区存在显著的条件β-收敛,其中工业化和创新能力是影响中部地区条件β-收敛的首要因素,政府过度干预经济的行为是阻碍其条件β-收敛的重要因素.     

脱硫石灰石粉生产线设计及应用

以姚孟电厂脱硫石灰石制粉工程为例,介绍了水泥粉磨技术在电厂脱硫剂制粉中的应用。运行结果表明,系统运行良好、效率高、能耗低,可作为电厂脱硫石灰石制粉的专门技术。