环糊精对腐植酸-芘、蒽相互作用影响初探

利用吸收光谱、荧光猝灭法、圆二色谱法及芘荧光探针法,探讨了环糊精(CDs)对腐植酸(HA)与以芘为代表的多环芳烃(PAHs)相互作用的影响.β-CD与HA的吸收光谱和荧光光谱测定结果表明:β-CD能够包络HA的芳环部分;荧光猝灭法和圆二色谱法测定结果表明:HA能够与被β-CD空腔包络的芘分子发生相互作用,CDs和HA之间存在与芘相互作用的竞争;用荧光猝灭法测定了四种不同CDs存在下HA和芘的结合常数,并用芘为荧光探针进行测定,结果表明:CDs浓度较低时,HA对芘的作用占优势;反之,CDs占优势.与其它三种CDs不同,γ-CD存在下HA与芘的结合常数随其浓度的升高一直增大.     

Mapping of temperature and line-of-sight errors in constituent retrievals for MIPAS/ENVISAT measurements

An optimized code for the near real-time retrieval of line of sight, temperature and volume-mixing ratio profiles of five key species (O₃, H₂O, HNO₃, CH₄ and N₂O) from infrared limb spectra recorded by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) experiment on board the ENVISAT-1 satellite was developed as part of an ESA-supported study. In this code line of sight and temperature are retrieved simultaneously among themselves, but sequentially with respect to the volume-mixing ratio of the five key species. The sequential retrieval leaves unaccounted the mapping of line of sight and temperature errors in the retrieved volume-mixing ratio of the constituents. This paper illustrates an algorithm that provides the a-posteriori evaluation of temperature and line-of-sight-induced error on the retrieved volume-mixing ratio of the MIPAS key species. It is shown that in most cases temperature and line-of-sight-induced error provides a significant contribution to the total volume-mixing ratio error. The variability of this error as a function of latitude, season and atmospheric model is also analyzed.     

E2诱导的鲫鱼(Carassius auratus)幼鱼血清中卵黄蛋白原和钙含量相关性研究

用酶联免疫吸附法(ELISA)对E2诱导的鲫鱼幼鱼血清中卵黄蛋白原(VTG)进行了测定,并用原子吸收分光光度法测定了血清中的钙含量.结果表明:鲫鱼幼鱼血清中VTG和钙含量与E2的暴露剂量均有很好的剂量-效应关系.对血清中VTG和钙含量进行回归分析,发现二者具有较好的相关性,R2=0.928 7.因此,用原子吸收法测定血清中的钙含量从一定程度上可以替代ELISA法间接确定血清中的VTG含量,并对化学物质的雌激素效应进行了评价.      

铵盐气溶胶对烟气排放连续监测系统颗粒物比对监测的影响研究

利用拉曼光谱对采样后的滤筒进行分析,发现废气中的硫酸铵-硫酸氢铵气溶胶是造成成都市部分企业烟气排放连续监测系统(CEMS)颗粒物比对监测结果不合格的主要原因。通过比较分析得出:在对含硫酸铵-硫酸氢铵气溶胶废气进行颗粒物浓度比对监测时,参比方法(重量法)测定的颗粒物浓度是一定标干采样体积下废气中固体微粒和硫酸铵-硫酸氢铵液体微粒结晶后产生的晶体的总质量,基于光散射法的CEMS颗粒物浓度测试系统测定的颗粒物浓度只是一定标干采样体积下废气中固体微粒的质量,由此导致参比方法测出的颗粒物浓度远大于CEMS测出的浓度,造成比对误差远超出允许值范围。     

Characterization of fulvic acids during olive mill waste composting (Elemental, Thermal and fluorescence analyses)

Elemental analysis, fluorescence spectroscopy and differential scanning calorimetry (DSC) were applied to the study of fulvic acids isolated from different stages during olive mill waste composting. The fulvic extracted acids are characterized by a high nitrogen content and O/C ratio values that may result from the high degree of humification and the synthesis of more condensed humic complexes. This was confirmed by fluorescence spectroscopy in the synchronous-scan mode by the decrease of shoulder intensities at intermediate wavelengths indicating the increase of polycondensation and conjugation of unsaturated structures and the greater uniformity of fluorophores. Fluorescence spectra in the emission, excitation and synchronous modes became simpler with compost maturation. This was confirmed by DSC results which proved the high degree of polycondensation of aromatic nuclei of fulvic acid molecules during olive mill waste composting.     

氟碳涂料实验室循环盐雾试验后防腐蚀行为研究

目的 研究氟碳重防腐涂层在循环盐雾试验后的防护性能.方法 开展氟碳涂层的实验室循环盐雾试验,通过电化学阻抗谱、附着力、光泽、色差测试等方法对氟碳涂层的各性能进行分析表征,并使用等效电路图对电化学阻抗谱数据进行拟合,评价涂层在盐雾试验后的腐蚀保护性能.结果 循环盐雾试验1440 h后,涂层无失光、变色、粉化等现象,模值由1.42×1011?·cm2下降至7.26×1010?·cm2,下降幅度较小.结论 经循环盐雾试验后的氟碳涂层仍具有优异的防护性能.     

Synchronous-scan fluorescence spectra of Chlorella vulgaris solution

The characterization of the Chlorella vulgaris solution was carried out using synchronous-scan spectroscopy. The range of concentration of algae and Fe(III) in aqueous solutions were 5 × 10⁸–8 × 10⁹ cells l⁻¹ and 10–60 μM, respectively. Effective characterization method used was synchronous-scan fluorescence spectroscopy. The wavelength difference (Δλ) of 90 nm was maintained between excitation and emission wavelengths; 90 nm was found to be the best Δλ for effective characterization of Chlorella vulgaris solution with or without quencher species (e.g., Fe(III), humic acid (HA)) for the first time. The peak was observed at about EX 236.6 nm/EM 326.6 nm for synchronous-scan fluorescence spectra. The fluorescence quenching of algae in system of algae–Fe(III)–HA was studied using synchronous-scan spectroscopy for the first time. Fe(III) was clearly the effective quencher. The relationship between I₀/I (quenching efficiency) and c (concentration of Fe(III) added) was a linear correlation for the algae solution with Fe(III). Also, Aldrich humic acid was found to be an effective quencher. pH effect on synchronous-scan fluorescence intensity of algal solution with Fe(III) and/or HA was evident.     

Investigation of fault position and sources of radon by measurement of 238U decay series radionuclide activity in soil samples

North Derbyshire is designated a Radon Affected Area by the National Radiological Protection Board of Great Britain since more than 1% of the housing stock is estimated to have radon levels in excess of the 200 Bq m-3 Action Level. Enhanced radon emissions associated with geological faults make knowledge of their position important in relation to any potential residential or industrial development. A general survey of radionuclides present in the soils of north Derbyshire and their relationship to the underlying geology highlighted the difficulty of identifying the position of geological faults in the field. Using gamma-ray spectroscopy of soil samples the activity of three 238U decay series radionuclides (226Ra, 214Pb and 214Bi), which were taken as evidence of the presence of 222Rn which occurs in the same decay series, was measured to indicate the position of a fault by enhanced activity. The results also provided some evidence of the source of radon emitted at the fault. A comparison of this methodology with the more conventional soil gas analysis method is made.     

用荧光光谱研究腐殖酸与金属离子Al^3＋的配合作用

用同步荧光法对两种来源不同的腐殖酸与金属离子Ａｌ＾３＋的配合作用进行了研究,采用非线性回归分析,用荧光强度变化数据,拟合出金属配合物（１：１）的条件稳定常数Ｋ,在配合滴定进行的同时,探讨了溶液在５００ｎｍ处的瑞利散射现象。