2,4-二磺酸基苯基重氮氨基偶氮苯与Cd(Ⅱ)的显色反应

合成新显色剂2,4-二磺酸基苯基重氮氨基偶氮苯(简称DSDAA),将其与镉进行显色反应,测定了一些影响因素。实验结果表明,在非离子表面活性剂TritonX-100及碱性介质存在下,显色剂与镉离子形成2:1的红色络合物,λmax为530nm,ε为2.25×105L.mol-1.cm-1,镉含量在0.06-11μg/25mL范围内符合比耳定律,在掩蔽剂1%NaF-硫脲-柠檬酸钠下,测定环境水样和工业废水中微量镉。     

Waste frying oil as a precursor for one-step synthesis of sulfur-doped carbon dots with pH-sensitive photoluminescence

Proper disposal of waste frying oil (WFO) is an important waste-management concern. In this paper, we develop a facile method to reuse WFO for one-step synthesis of sulfur-doped carbon dots (S-C-dots) with the assistance of concentrated sulfuric acid. The as-synthesized S-C-dots are uniform in size and show partial disordered graphite-like structure. Different from the doping-free or nitrogen-doped carbon dots, the S-C-dots perform a strong ultraviolet emission at 378 nm due to successful sulfur-doping. Noticeably, the S-C-dots exhibit a distinct pH-sensitive feature and the intensity of photoluminescence increases linearly in the pH range from 3 to 9. Furthermore, possessing fascinating optical properties, high photostability, and low cytotoxicity, the S-C-dots have served as fluorescent probes for cell imaging.     

A potential practical approach to reduce Ara h 6 allergenicity by gamma irradiation

Peanut allergen Ara h 6 was isolated and irradiated at 1, 3, 5, or 10 kGy, and a whole peanut protein extract (WPPE) was also treated by irradiation. Alteration in structure of Ara h 6 was characterised by circular dichroism (CD) spectroscopy, ultraviolet (UV) absorption spectroscopy, fluorescence spectroscopy and SDS–PAGE, and antigenicity was evaluated by immunoblotting and indirect ELISA with anti-Ara h 6 polyclonal antibody. Irradiation induced significant changes in the secondary and tertiary structures of Ara h 6, and the antigenicity of both purified Ara h 6 and WPPE were reduced upon increasing the irradiation doses. Moreover, a good correlation between the loss in α-helix and IgG binding to Ara h 6 was observed. This indicated that irradiation might be an efficient approach to reduce or eliminate peanut allergenicity.     

Thermal decomposition and kinetics of rigid polyurethane foams derived from sugarcane bagasse

Rigid polyurethane foams were fabricated with five kinds of liquefied sugarcane bagasse polyols (LBP). The foams derived from sugarcane bagasse were investigated by thermogravimetric analysis (TGA), and the thermal degradation data were analyzed using the Coast-Redfern method and Ozawa method to obtain the reaction order and activation energy. The results indicate that the sugarcane bagasse-foams exhibit an excellent heat-resistant property, whereas their pyrolysis procedures are quite complicated. The reaction as first order only takes place from 250 to 400 °C, and the pyrolysis activation energies vary from 20 to 140 kJ/mol during the whole pyrolysis process.     

甲基二氯硅烷-二甲基二氯硅烷-苯体系等压汽液平衡

卤代硅烷的相平衡数据为硅烷生产所需,而这方面的研究又较缺乏,尤其是甲基乙烯基二氯硅烷生产中所需的汽液相平衡数据尚未见报道.本文用新型泵式沸点仪测定了常压（101.325 kPa ）下甲基二氯硅烷＋二甲基二氯硅烷＋苯三元体系和三个二元体系在不同液相组成时的泡点.由所测的二元系数据,用过量自由焓Q函数间接法推算了与之平衡的汽相组成,获得的汽液相平衡数据（VLE）符合热力学一致性;用最小二乘法求出二元体系的Wilson、NRTL、Margules、van Laar方程最佳配偶液相活度系数模型参数,所得的最佳配偶液相活度系数模型参数较好地满足于系统;将所得的最佳Wilson模型参数直接用于该体系三元系汽液相平衡数据的预测,将计算的泡点与实验测得的泡点作了比较,其拟合精度良好,关联结果令人满意;给出了苯溶液中甲基二氯硅烷对二甲基二氯硅烷的相对分离因子.硅烷二元系、多元系的热力学模型及VLE数据可为该体系的分离设计提供必要的理论依据.     

Simultaneous Removal of Phenol and Nitrate in an Anaerobic Bioreactor

Phenol and nitrate are two major pollutants simultaneously occurring in several industrial wastewaters. In this study, a 110-day gradual enrichment of an anaerobic culture has been carried out at 25°C in an anaerobic bioreactor for continuously treating a synthetic wastewater containing 600?mg/L phenol and 430?mg/L?NO3?–N. The results showed that the enriched culture can utilize phenol as a sole electron donor and nitrate as a sole electron acceptor. At the end of the enrichment (on Day 110), 93.3% of phenol and 98.0% of NO3?–N were simultaneously removed at a hydraulic retention time of 20.25?h in the anaerobic bioreactor. The removal of 1?g?NO3?–N required about 3.19?g chemical oxygen demand as the electron donor. Batch tests further revealed that cresol, nitrophenol, and monochlorinated phenol (MCP) could exert detrimental influences on the treatment abilities of the enriched culture. However, the inhibitory effects of cresol were impermanent, as compared to those of nitrophenol and MCP. In order to operate the anaerobic bioreactor steadily, high concentrations of cresol should be diluted before being fed while the existence of nitrophenol and MCP in the bioreactor should be avoided.     

Preparation and Characterization of Porous Yttrium Oxide Powders with High Specific Surface Area

Y2O3isoftenusedinthemanufactureofphos phorsandceramics[1～3].However,itisalsousedas selectivecatalysts[1,4,5],suchasforthedehydrationof2alkanols,thedimerizationofmethane,1butene isomerization,hydrogenationof1,3butadieneandac etonealdoladdition,andsupport[6,7]formetalsthat catalyzetheformationofmethanolfromCO2andH2.It iswidelyacceptedthatthecatalysispropertiesofox idesdependstronglyontheirphysicalcharacteristics,especiallyontheirspecificsurfaceareaandporous structure.Agreatdealofattentionhasb…     

Rose Bengal-Cu-TiO2的制备及可见光制氢活性研究

用光还原方法制备了负载Cu的光催化剂Cu-TiO2，并通过染料Rose bengal敏化，制备了具有可见光活性的Rose bengal-Cu-TiO2光催化剂，通过可见光下光解水制氢考察了催化剂的活性，并利用XRD、UV-Vis等手段对样品进行了表征。实验表明：载Cu增强了TiO2对可见光的吸收，Cu负载量对催化剂活性有一定的影响，Cu的最佳负载量为5％（质量分数）。Cu的负载也增加了TiO2对染料的吸附强度和吸附量，从而提高了TiO2对可见光的吸收和光催化活性。但载Cu的TiO2催化剂的活性和传统的载贵金属Pt的TiO2催化剂相比，其光催化活性较低，有待进一步提高．