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601.
蛋白质和磷酸水解酶在废水处理系统中的活性和作用 总被引:1,自引:0,他引:1
通过分析亮氨酸氨基肽酶和碱性磷酸酶,研究了厌氧-缺氧-好氧废水处理系统中蛋白质和磷酸水解酶的活性及其作用.结果表明,亮氨酸氨基肽酶存在缺氧和好氧池中的活性分别达19.2 цmol L-1 h-1和21.6 ц mol L-1 h-1;而碱性磷酸酶在厌氧池中占主导地位,平均活性达32.5 ц mol L-1,h-1,好氧池中的活性只有厌氧池的一半,缺氧池中的酶活性最小.动力学研究得到,厌氧条件碱性磷酸酶的最大反应速度v 为778.42 ц mol L-1 h-1,是亮氨酸氨基肽酶Vmax值的一百倍以上;亮氨酸氨基肽酶的Vmax值在厌氧、缺氧、好氧池中依次增大.此外,外加的NO2-、NO3-离子对亮氨酸氨基肽,酶和P043-离子对碱性磷酸酶的活性均有不同程度的促进作用,只有浓度为50 mg/L的P043-对碱性磷酸酶有显著的抑制. 相似文献
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605.
提出了测定水中总铁的新方法-邻菲哆啉直接光度法。该方法检出限为0.03mg/L,显色络合物显色15min后可稳定6个月,精密度RSD〈4.32%,加标回收率为95.3%~103%。对地下水、地表水、工业废水和铁标准样品的比对实验表明,邻菲哆啉直接光度法与邻菲哆啉光度法(标准法)的测定结果无显著差异。 相似文献
606.
607.
提出了测定水中总铁的新方法-邻菲哆啉直接光度法。该方法检出限为0.03mg/L,显色络合物显色15min后可稳定6个月,精密度RSD〈4.32%,加标回收率为95.3%~103%。对地下水、地表水、工业废水和铁标准样品的比对实验表明,邻菲哆啉直接光度法与邻菲哆啉光度法(标准法)的测定结果无显著差异。 相似文献
608.
对氨基苯磺酸降解菌的分离鉴定及降解特性研究 总被引:5,自引:3,他引:2
对大连某城市污水处理厂活性污泥进行长期驯化,筛选得到好氧条件下以对氨基苯磺酸(4-aminobenzenesulphonate,4-ABS)为唯一碳源和能源生长的高效降解菌株W1.根据菌株W1的形态特征、生理生化特征及16S rDNA序列分析,初步鉴定为Pannonibacter菌属.通过考察生长条件对降解效果的影响,确定了该菌株降解4-ABS的优化条件为:接种量10%、 30℃、 pH 7、摇床转速150 r/min,并且在有外加碳源的情况下仍保持较高的4-ABS降解活性.在4-ABS的降解过程中,4-ABS自身含有的氨基和磺酸基会以NH+4和SO2-4的形式释放到水体中,但浓度仅为理论释放量的77.6%和91.5%,推测原因是部分释放的NH+4和SO2-4被菌株W1作为氮源和硫源利用;菌株W1可以耐受2 500 mg/L的4-ABS,且在32 h内实现90%的降解率;4-ABS降解率为94.7%时,可以实现84.4%的TOC去除率,且没有检测到其它芳香化合物生成,表明菌株W1可以实现4-ABS的彻底矿化. 相似文献
609.
G. K. Parshetti S. G. Parshetti A. A. Telke D. C. Kalyani R. A. Doong P. Govindwar 《环境科学学报(英文版)》2011,23(8):1384-1393
Agrobacterium radiobacter MTCC 8161 completely decolorized the Crystal Violet with 8 hr (10 mg/L) at static anoxic conditions.
The decreased decolorization capability by A. radiobacter was observed, when the Crystal Violet concentration was increased
from 10 to 100 mg/L. Semi-synthetic medium containing 1% yeast extract and 0.1% NH4Cl has shown 100% decolorization of
Crystal Violet within 5 hr. A complete degradation of Crystal Violet by A. radiobacter was observed up to 7 cycles of repeated
addition (10 mg/L). When the effect of increasing inoculum concentration on decolorization of Crystal Violet (100 mg/L) was
studied, maximum decolorization was observed with 15% inoculum concentration. A significant increase in the activities of laccase
(184%) and aminopyrine N-demethylase (300%) in cells obtained after decolorization indicated the involvement of these enzymes
in decolorization process. The intermediates formed during the degradation of Crystal Violet were analyzed by gas chromatography
and mass spectroscopy (GC/MS). It was detected the presence of N,N,N′,N′′-tetramethylpararosaniline, [N; N-dimethylaminophenyl]
[N-methylaminophenyl] benzophenone, N; N-dimethylaminobenzaldehyde, 4-methyl amino phenol and phenol. We proposed the
hypothetical metabolic pathway of Crystal Violet biodegradation by A. radiobacter. Phytotoxicity and microbial toxicity study showed
that Crystal Violet biodegradation metabolites were less toxic to bacteria (A. radiobacter, P. aurugenosa and A. vinelandii) contributing
to soil fertility and for four kinds of plants (Sorghum bicolor, Vigna radiata, Lens culinaris and Triticum aestivum) which are most
sensitive, fast growing and commonly used in Indian agriculture. 相似文献
610.
Performance of dithiocarbamate-type flocculant in treating simulated polymer
flooding produced water
Produced water from polymer flooding is di cult to treat due to its high polymer concentration, high viscosity, and emulsified
characteristics. The dithiocarbamate flocculant, DTC (T403), was prepared by the amine-terminated polyoxypropane-ether compound
known as Je amine-T403. The product was characterized by IR spectra and elemental analysis. The DTC agent chelating with Fe2+
produced a network polymer matrix, which captured and removed oil droplets e ciently. Oil removal by the flocculent on simulated
produced water with 0, 200, 500, 900 mg/L of partially hydrolyzed polyacrylamide (HPAM) was investigated for aspects of e ectiveness
of DTC (T403) dosage and concentrations of HPAM and Fe2+ ions in the wastewater. Results showed that HPAM had a negative
influence on oil removal e ciency when DTC (T403) dosage was lower than 20 mg/L. However, residual oil concentrations in
tested samples with di erent concentrations of HPAM all decreased below 10 mg/L when DTC (T403) dosage reached 30 mg/L.
The concentration of Fe2+ in the initial wastewater had a slight e ect on oil removal at the range of 2–12 mg/L. Results showed that
Fe3+ could not be used in place of Fe2+ as Fe3+ could not react with DTC under flocculated conditions. The e ects of mineral salts ions
were also investigated. 相似文献