固定化毛霉对工业和农田污染土壤中多环芳烃的降解和生物有效性评价

为了探讨微生物修复不同类型多环芳烃污染土壤的可行性,应用固定化毛霉对多环芳烃污染工业土壤及农田土壤进行微生物修复,用羟丙基-β-环糊精(HPCD)提取模拟评价多环芳烃的微生物可利用性,并分析多环芳烃微生物降解和生物可利用性的相关关系.焦化厂污染土壤中多环芳烃的30 d降解率为77.6%,沈抚灌区污染土壤中多环芳烃的30 d降解率为54.2%,焦化厂土壤和污灌区农田土壤中多环芳烃降解差异明显.焦化厂土壤和污灌区土壤中多环芳烃的30 d降解量和多环芳烃的环糊精可提取量具有相关性,各环数多环芳烃的环糊精可提取量变化解释了焦化厂和污灌区土壤中多环芳烃降解的差异机制,说明可用环糊精提取量预测微生物降解土壤多环芳烃的情况.     

FOP-EGSB-MBR组合工艺处理2-萘酚生产废水

2-萘酚生产废水具有COD高、BOD/COD值低和生物毒件高的特点,采用FOP-EGSB-MBR组合工艺对其模拟废水进行处理工艺的研究.结果表明:废水经Fenton氧化处理后,可将出水BOD/COD值从0.01提高至0.67;再经过厌氧和好氧处理后,出水COD为100 mg/L以下;该组合上艺总的COD去除去可达99%,且运行性能稳定,效果可靠.     

负载β-环糊精的矿物和生物炭对甲基橙的吸附性能

采用HCl溶液对沸石（F0）、蛭石（ZH0）、秸秆（J0）和棕榈生物炭（Z0）进行活化预处理,以环氧氯丙烷为交联剂,将β-环糊精（β-CD）负载到原始材料上,制备了4种新型吸附材料F2、ZH2、J2和Z2。采用FTIR、元素分析、SEM和TG等技术对吸附材料进行了表征,探讨了其对甲基橙的吸附性能。表征结果显示,β-CD被成功地负载到沸石、蛭石、秸秆生物炭和棕榈生物炭上。吸附实验结果表明：负载β-CD后的4种材料对甲基橙的平衡吸附量大小顺序为J2> F2> ZH2> Z2;溶液pH和吸附温度的提高可有效提升4种材料对甲基橙的吸附能力。吸附动力学和热力学研究表明,4种材料对甲基橙的吸附过程中物理吸附起着主导作用,且更趋向于单分子层吸附。4种材料均具有良好的重复使用性能。     

Preparation and evaluation of Zr-β-FeOOH for efficient arsenic removal

A Zr-β-FeOOH adsorbent for both As(V) and As(III) removal was prepared by a chemical co-precipitation method.Compared with β-FeOOH,the addition of Zr enhanced the adsorption capacities for As(V) and As(III),especially As(III).The maximum adsorption capacities for As(III) and As(V) were 120 and 60mg/g respectively at pH 7.0,much higher than for many reported adsorbents.The adsorption data accorded with Freundlich isotherms.At neutral pH,for As(V),adsorption equilibrium was approached after 3 hr,while for As(III),adsorption equilibrium was approached after 5 hr.Kinetic data fitted well to the pseudo second-order reaction model.As(V) elimination was favored at acidic pH,whereas the adsorption of As(III) by Zr-β-FeOOH was found to be effective over a wide pH range of 4-10.Competitive anions hindered the adsorption according to the sequence:phosphate > silicate > bicarbonate > sulfate > nitrate,while Ca2+ and Mg2+ increased the removal of As(III) and As(V) slightly.The high adsorption capability and good performance in other aspects make Zr-β-FeOOH a potentially attractive adsorbent for the removal of both As(III) and As(V) from water.     

The amplification refractory mutation system (ARMS): A rapid and direct prenatal diagnostic technique for β-thalassaemia in Singapore

β-Thalassaemia major patients have chronic anaemia and since 3–4 per cent of Singaporeans carry the β-gene, prenatal diagnosis is essential. We evaluated the amplification refractory mutation system (ARMS) technique as a routine test for prenatal diagnosis of β-major. Six mutations along the β-gene were studied—41–42 (-TCTT), IVSII #654 (C-T), 17β (A-T), – 28 TATA (A-G), IVSI #5 (G-C), and IVSI #1 (G-T). Our results indicate that prenatal diagnosis using these mutations can be offered to 90 per cent (35/39) of our Chinese couples and 54·6 per cent (12/22) of our Malay couples at risk. Confirmation of ARMS results was carried out using allele-specific oligonucleotide hybridization. Prenatal diagnosis using ARMS was successfully carried out in nine cases which included a set of triplets and twins. The triplets were diagnosed with the β-trait carrying the 41–42 mutation. The couple with twins possessed the #654 mutation and one twin was diagnosed with the β-trait and the other with #654 homozygosity. Genomic sequencing of the undefined mutations in the Chinese couples revealed rarer mutations at − 29 and an ATG-AGG base substitution at the initiation codon for translation. In the Malay couples, genomic sequencing detected mutations at codon 15 (TGG-TAG) and codon 26 (GAG-AAG). We conclude that ARMS with its direct detection of amplified products by gel electrophoresis provides an accurate, rapid, and simpler method for our β-thalassaemia prenatal diagnosis programme in Singapore.     

Amniotic fluid pregnancy-specific β1-glycoprotein (SP1) in Meckel's syndrome: A new test for prenatal diagnosis?

Amniotic fluid levels of pregnancy-specific β₁-glycoprotein (SP₁) were elevated in four pregnancies with Meckel's syndrome at 16 and 26 weeks, and the levels of hCG were also elevated in three out of four cases. These findings suggest a potential new application of SP₁ measurement for prenatal diagnosis.     

A simple electrophoretic procedure for fetal diagnosis of β-thalassaemia due to short deletions

This study describes three couples a t risk for homozygous β-thalassaemia in which one of the partners carried a short deletion β-thalassaemia defect. Detection of short deletions in trophoblast DNA was accomplished by the very simple procedure of non-denaturing polyacrylamide gel electrophoresis. This method may be applied to detect β-thalassaemia mutations due to deletion or addition of more than two nucleotides.     

Methyl-β-cyclodextrin enhanced biodegradation of polycyclic aromatic hydrocarbons and associated microbial activity in contaminated soil

The contamination of soils by polycyclic aromatic hydrocarbons (PAHs) is a widespread environmental problem and the remediation of PAHs from these areas has been a major concern.The effectiveness of ma...