壳聚糖及其衍生物在工业废水处理中的应用研究进展

壳聚糖是一种对环境友好同时具有多种特性的天然高分子聚合物。以壳聚糖及其衍生物处理工业废水,安全无毒、可生物降解、无二次污染。对国内外近年来壳聚糖及其衍生物在印染、电镀、食品加工、造纸等工业废水处理方面的研究和应用进展进行了扼要的综述。     

Preparation of ceria-zirconia solid solution with enhanced oxygen storage capacity and redox performance

A new method called ultrasonic-assisted membrane reaction (UAMR) was reported for the fabrication of ceria-zirconia solid solution. A series of ceria-zirconia solid solutions with different Ce/Zr molar ratios were prepared by the UAMR method and characterized by X-ray diffraction (XRD), N₂ adsorption, hydrogen temperature-programmed reduction (H₂-TPR), scanning electron microscope (SEM), and transmission electron microscopy (TEM) techniques. The UAMR method proved to be superior, especially when the Ce/Zr molar ratio was lower than 1, in fabricating ceria-zirconia solid solutions with large BET surface area, high oxygen storage capacity (OSC), and low reduction temperature.     

钛酸铋光催化降解水中酸性大红的研究

采用异丙醇助水热法制备了钛酸铋光催化剂,UV-vis漫反射测试表明其光吸收带较TiO2发生了红移,通过多点BET法计算出其比表面积为14.16m2/g,平均孔径为21.05nm。以酸性大红为模拟污染物,在三相内循环流化床光催化反应器中进行光催化反应,研究了废水的pH值以及钛酸铋投加量对酸性大红脱色率的影响。结果表明:废水的pH=3.0,催化剂投加量为0.1g/L是最佳反应条件;当流量为10L/h时,连续运行3h后,酸性大红染料的去除率可达92.0%;当处理水量增大时,经过两级处理,酸性大红染料的总去除率仍可达到94.4%。     

直接大红4BE染料吸附脱色真菌的分离及特性研究

通过梯度富集培养,筛选到一株偶氮染料直接大红4BE吸附脱色真菌HS-DY08,该菌在基础培养基中,30℃、150r/min条件下,24h内对浓度为30mg/L的直接大红4BE的吸附脱色率达92%。脱色液动态扫描结果显示,随着HS-DY08菌株对染料的吸附脱色降解,直接大红4BE的吸收峰(526nm)明显降低,中间产物(325nm)的吸收峰逐渐升高,且染料吸附过程中菌体生长量增加,表明菌株对染料的吸附脱色过程中伴随着对染料的生物降解和利用。不同的共基质底物对直接大红4BE吸附脱色能力的促进作用依次为:PDB>葡萄糖>蛋白胨>NH4Cl。结合形态特征及显微观察结果,初步鉴定HS-DY08为青霉属(Pemnicillium sp.)。     

Response of soil microorganisms to vegetational succession in Ziwuling Forest

This study investigates the changes in soil microbial populations as vegetational succession progress from abandoned farmland to climax forest in the Ziwuling Forest, which is located in the northern part of the Loess Plateau, China. Different organic C and total extractable N between the fumigated and non-fumigated soils were assumed to be released from soil microorganisms. Soil microbial C was calculated using Kec = 0.38 and microbial N was calculated using Ken = 0.45. The released P was converted to microbial biomass P using Kep = 0.40. Soil bacteria, fungi, and actinomycetes increased as the vegetational succession progressed. Microbial C was of the highest amount in farmland. Microbial C, N, and P generally increased from abandoned land to climax community. The results indicated significant (P < 0.05) diversities of soil microbial biomass under different vegetation. There was a significant correlation between microbial biomass and soil nutrients. Knowledge about soil microbial populations is important for forecasting vegetational succession and determining the ecological condition of the environment.     

红外分光光度法测定水中动植物油的不确定度评定

文章对红外分光光度法测定水中动植物油的不确定度来源进行了分析,构造出合理的数学模型,确定了各输入量之间的关系,量化各分量后,合成得到满意的结果。从而提出,根据被测量及其所依赖的输入量之间的关系构造数学模型,并综合运用不同的评定方法对各个分量进行量化,可实现对某些检测项目的不确定度评定。     

辅助燃料对垃圾熔融炉炉温影响的分析研究

文章计算了在不同焦炭加入量及不同焦炭和煤的配比条件下处理城市生活垃圾时气化熔融炉的炉温。计算结果表明,用焚烧法处理重庆市的生活垃圾时,在常温鼓风条件下,要使垃圾灰渣完全熔融,焦炭配比至少应在42％以上;在一定的条件下,可以用煤部分或全部代替焦炭,同时配以高温鼓风,可使炉温达到并超过垃圾灰渣的熔融温度,从而使得垃圾灰渣熔融。     

沉箱结构体对水体原生动物种群的影响研究

针对天津外环河富营养化现状,采用微宇宙结构控制试验技术与正交试验分析方法,研究沉箱微宇宙控制因素对原生动物数量和种类的影响,共观测到各类原生动物9种,其中鞭毛纲3种,纤毛纲4种,肉足纲2种。夏季的优势种群为纤毛纲+肉足纲+鞭毛纲,而秋季的优势种群为鞭毛纲,原生动物种群的此类变化说明了这种结构控制体对夏秋季原生动物的影响有着显著的自然调控作用。结果表明最佳沉箱微宇宙结构体的控制条件是箱体为陶粒箱,基质为页岩,植物为金钱蒲+雨久花的结构组合;同时箱体材料、基质种类和植物配置在夏秋两季对原生动物数量的影响均为极显著。     

污染减排对城市降水和环境空气质量的影响

文章以2005～2008年湖南省二氧化硫、烟尘和工业粉尘的减排情况以及城市环境空气质量监测结果为基础,分析了大气污染减排对湖南省城市降水和城市环境空气质量的影响,阐述了大气污染减排取得的环境效益,为湖南省下一步的污染减排和环境管理政策及措施的制定提供了依据。     

含钛高炉渣制光催化剂降解水中2,4-二氯酚的研究

以攀钢含钛高炉渣为原料制备了光催化剂,并将其用于降解水中2,4-二氯酚,研究了光催化剂投加量、光照强度、反应物浓度、反应时间对2,4-二氯酚降解率的影响。结果表明:高炉渣制光催化剂对2,4-二氯酚具有良好的光催化效果,在催化剂投加量为0.3g/L,光照时间为2h的条件下,浓度为50mg/L的2,4-二氯酚的降解率达到了77.1%。通过反应的动力学分析,确立出高炉渣制光催化剂对水中2,4-二氯酚的降解反应为一级反应。对2,4-二氯酚的光催化降解产物进行分析发现,苯环上的C—Cl键被光催化剂产生的羟自由基·OH氧化断裂,氯取代基成为游离Cl-存在于溶液中,2,4-二氯酚被·OH降解生成中间小分子有机产物,这些小分子有机物再进一步被光催化降解。