碳纳米管电极原位产生过氧化氢及其对亚甲基蓝脱色效果简

将碳纳米管固定化制成多孔疏水性导电薄膜构建电化学阴极还原体系,实现过氧化氢在阴极的原位产生。电极特性研究表明,电极在较宽的电压范围内均具有较好的活性。考察了阴极电位、电极成分、氧气流量和电解质浓度对过氧化氢原位产生的影响,在优化条件下经过120 min后过氧化氢达到66.17 mg/L,并探讨过氧化氢原位产生的机理。在此基础上考察原位过氧化氢氧化工艺下对亚甲基蓝的脱色效果,并分析其脱色机理。     

水生植物酸碱预处理对厌氧发酵联产氢气-甲烷的影响简

采用酸碱预处理乌梁素海典型沉水植物龙须眼子菜和挺水植物芦苇,通过厌氧发酵动力学分析、还原糖变化及微观结构解析,研究酸碱预处理对水生植物厌氧发酵联产氢气-甲烷的影响。实验结果表明,酸碱预处理后水生植物厌氧发酵联产氢气-甲烷两阶段累积产气量、氢气及甲烷含量均显著提高,酸处理效果优于碱处理。采用0.5 mol/L HCl预处理龙须眼子菜效果最佳,最大氢气、甲烷含量分别达42.65%和52.82%,产氢气速率为4.118 mL/h,产甲烷速率最高达14.199 mL/h。芦苇经1 mol/L HCl预处理效果最佳,最高氢气、甲烷含量分别为32.22%和65.26%。扫描电镜微观结构分析表明,酸碱预处理可显著破坏芦苇、龙须眼子菜的纤维素结构,有效增加植物与微生物接触面积,有利于厌氧发酵联产氢气-甲烷工艺的快速启动和稳定运行。     

臭氧联用技术深度处理腈纶废水的效果对比

将臭氧分别与超声波、H2O2、紫外光等联用,深度处理干法腈纶生产厂生化池出水,对各种联用技术的处理效果进行了研究。实验结果表明：在进水流量2 L/min、反应时间30 min、臭氧加入量3.5 g/（L?h）的条件下,当超声功率为300 W时,臭氧-超声联用技术的COD去除率为30.0%;当H2O2加入量为0.4 mL/L时,臭氧-H2O2联用技术的COD去除率为50.7%;当紫外灯功率为40 W时,臭氧-紫外光联用技术的COD去除率为49.9%;在各种联用技术中,臭氧-H2O2联用技术的运行成本最低（为7.5 元/t）,且处理后出水COD为143 mg/L,达到《<污水综合排放标准>（GB8978—1996）中石化工业COD标准值修改单》中的一级排放标准。综合考虑,臭氧-H2O2联用技术是深度处理干法腈纶废水的最优工艺。     

含氨氮催化剂生产废水的处理

采用加入淀粉的短程硝化-反硝化一体化技术处理低碳含NH3-N催化剂废水。通过中试确定了适宜的工艺参数,并在工业化装置上进行了验证。试验结果表明：在DO为0.5 mg/L左右、淀粉加入量为0.25 kg/ m3、HRT=30 h的条件下,短程硝化-反硝化一体化技术具有较好的处理效果,NH3-N去除率大于97%,且具有较强的抗冲击负荷的能力; 出水的COD<100 mg/L,ρ（NH3-N）<10 mg/L,达到GB 8978—1996《污水综合排放标准》的一级排放标准。工业化装置的运行费用以NH3-N计为2.3 元/kg、以废水计为4.6 元/t。该法适用于中低浓度（ρ（NH3-N）<300 mg/L）废水的处理。     

酸性洗涤塔-生物滤塔-生物曝气池组合工艺处理恶臭气体NH3和H2S

采用酸性洗涤塔、生物滤塔和生物曝气池的组合工艺处理NH3、H2S恶臭混合气体,研究表明,该组合工艺对NH3和H2S有很好的去除效果,在进气流量为35 L/min,喷淋量45 L/h时,NH3进气浓度50.15~525.4 mg/m3,H2S进气浓度10.23~110.36 mg/m3时,NH3单一进气去除率稳定在99%以上,H2S单一进气去除率90%以上。混合进气后,NH3去除率几乎为100%,H2S的去除率提高至98%以上。在一定的浓度范围内,NH3和H2S之间的相互作用对两者的去除效果没有明显的影响,而且起到了相互促进降解的作用。同时,进气流量和填料层高度都会影响NH3、H2S的去除率。系统对进气容积负荷变化的缓冲能力强,在偶尔超负荷条件下运行并不能使系统崩溃,并且微生物对高负荷逐渐表现出适应性。大部分溶于水的氨由生物曝气池去除,去除率达到96.9%。     

二氧化钛脱除高温烟气中的氯化氢

HCl是城市垃圾焚烧产生的主要气体污染物之一。将一种新型脱氯剂TiO2引入到垃圾焚烧系统中,并与其他脱氯剂的性能进行比较。研究了不同脱氯剂使用量、不同反应温度和不同HCl气体浓度对TiO2、CaO和CaTiO3脱氯效果的影响。结果显示,TiO2能在高温(800~1 000℃)、高HCl浓度(1 303.6~1 629.5 mg/m3)下获得较好的脱氯效果。与传统的脱氯剂CaO相比,TiO2更适合于高温烟气脱氯,其在1 000℃时的氯容(36.3 mg HCl/g TiO2)几乎是相同情况下的CaO氯容(9.3 mg HCl/g CaO)的4倍。而CaTiO3的脱氯效果不但受到自身分解效率的影响,还受到TiO2和CaO脱氯效果的影响,其脱氯效果较差。     

Treatment of wastewater from red and tropical fruit wine production by zeolite anaerobic fluidized bed reactor

A study of the anaerobic treatment of wastewaters derived from red (RWWW) and tropical fruit wine (TFWWW) production was carried out in four laboratory-scale fluidized bed reactors with natural zeolite as bacterial support. These reactors operated at mesophilic temperature (35°C). Reactors R1 and R2 contained Chilean natural zeolite, while reactors R3 and R4 used Cuban natural zeolite as microorganism support. In addition, reactors R1 and R3 processed RWWW, while reactors R2 and R4 used TFWWW as substrate. The biomass concentration attached to zeolites in the four reactors studied was found to be in the range of 44–46 g volatile solids (VS)/L after 90 days of operation time. Both types of zeolites can be used indistinctly in the fluidized bed reactors achieving more than 80%–86% chemical oxygen demand (COD) removals for organic loading rates (OLR) of up to at least 20 g COD/L d. pH values remained within the optimal range for anaerobic microorganisms for OLR values of up to 20 and 22 g COD/L d for RWWW and TFWWW, respectively. Toxicity and inhibition levels were observed at an OLR of 20 g COD/L d in reactors R1 and R3 while processing RWWW, whereas the aforementioned inhibitory phenomena were not observed at an OLR of 24 g COD/L d in R2 and R4, treating TFWWW as a consequence of the lower phenolic compound content present in this substrate. The volatile fatty acid (VFA) levels were always lower in reactors processing TFWWW (R2 and R4) and these values (< 400 mg/L, as acetic acid) were lower than the suggested limits for digester failure. The specific methanogenic activity (SMA) was twice as high in reactors R2 and R4 than in R1 and R3 after 120 days of operation when all reactors operated at an OLR of 20 g COD/L d.     

Nickel induced alteration of hen body weight,egg production and egg quality after an experimental peroral administration

In this study the effects of nickel (NiCl₂) administered in drinking water (0.02; 0.2 and 2.0 mg NiCl₂/L for 28 days) on laying hen body weight, egg production and egg quality is reported. Growth parameters during the experiment were significantly decreased mainly in the group with the highest nickel concentration. In total egg production dose–dependent decrease in all experimental groups was found. Egg weight was mainly affected in the group with the highest nickel concentration. Specific egg weight was not altered. Albumen weight and albumen content was significantly decreased in groups with the highest nickel concentration in comparison with the control group.

Egg yolk analysis detected significantly decreased yolk weight in the group with the highest nickel experimental level. In yolk color a significant difference was detected between the group receiving 0.02 and 0.2 mg NiCl₂/mL. Eggshell compactness was increased in all experimental groups what could be induced by altered mineralization of eggshell. Results of this study clearly report a negative effect of nickel as an environmental pollutant on laying hen body weight, egg production as well as egg quality.     

Kinetics study of fermentative hydrogen production from liquid swine manure supplemented with glucose under controlled pH

Kinetics of H₂ production from liquid swine manure supplemented with glucose by mixed anaerobic cultures was investigated using batch experiments under four different pH conditions (4.4, 5.0, 5.6, and uncontrolled). The temperature for the experiments was controlled at 37 ± 1°C and the length of experiments varied between 50 and 120 hours, depending upon the time needed for completion of each individual experiment. The modified Gompertz model was evaluated for its suitability for describing the H₂ production potential, H₂ production rate, and substrate consumption rate for all the experiments. The results showed that the Gompertz model could adequately fit the experimental results. The effect of pH was significant on all kinetic parameters for H₂ production including yield, production rate and lag time, and the substrate utilization rate. The optimal pH was found to be 5.0, at which a maximum H₂ production rate (0.64 L H₂/h) was obtained, and deviation from the optimal pH could result in substantial reductions in H₂ production rate (0.32 L H₂/h for pH 4.0 and 0.43 L H₂/h for pH 5.6). The results also showed that if pH was not controlled for the batch fermentation process, the substrate utilization efficiency could steeply decrease from 98.8% to 33.7%.     

QSPR prediction of chromatographic retention times of pesticides: Partition and fractal indices

The high‐performance liquid‐chromatographic retentions of red‐wine pesticide residues are modeled by structure–property relationships. The effect of different types of features is analyzed: geometric, lipophilic, etc. The properties are fractal dimensions, partition coefficient, etc., in linear and nonlinear correlation models. Biological plastic evolution is an evolutionary perspective conjugating the effect of acquired characters and relations that emerge among the principles of evolutionary indeterminacy, morphological determination and natural selection. It is applied to design the co‐ordination index that is used to characterize pesticide retentions. The parameters used to calculate the co‐ordination index are the molar formation enthalpy, molecular weight and surface area. The morphological and co‐ordination indices barely improve the correlations. The fractal dimension averaged for non?buried atoms, partition coefficient, etc. distinguishes the pesticide molecular structures. The structural and constituent classification is based on nonplanarity, and the number of cycles, and O, S, N and Cl atoms. Different behavior depends on the number of cycles.