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The sensitivity of poly(arylsulfone)(PSf) for UV irradiation in different solvents(water and ethanol) was investigated. It is confirmed that acrylic acid(AA) and acrylamide(AAm) are grafted only onto the surface of the membrane instead of the interior by FTIR and scanning electron microscope(SEM). The membrane performance (ΔJ/J0 and contact angle θ) after photografting was studied. In the range of conditions used, the grafting yield increases with irradiation time and monomer concentration growing. After photografting and N-3-dimethylaminopropyl-N‘-ethycarbodiimide hydrochloride(EDC) activation, PSf membrane was immobilized with hydrogen peroxide oxidoreductase, and showed a higher activity than the control membrane. 相似文献
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用一种具有多孔结构特征的沸石球作为载体固定化硝化细菌强化吸附氨氮废水。结果表明,沸石球能快速固定化硝化细菌,吸附动力学表明150 min对氨氮吸附容量达到2.816 mg/g,而且还有继续增加的趋势。假二级动力学方程和Elovich模型的精确拟合说明,生物沸石球对氨氮的吸附过程可能是非均相扩散起作用及以化学吸附反应为主的复杂转化过程。扩散拟合结果表明,氨氮在生物沸石球的吸附是以液膜扩散和颗粒内扩散为吸附速率的控制步骤,活性的硝化细菌对氨氮的硝化使氨氮在微孔的吸附得到了强化。 相似文献
235.
浅议橡胶废水处理技术 总被引:4,自引:0,他引:4
论述了生物载体生化法处理橡胶废水的工艺技术.通过生产性试验和正在用该工艺运行的两家橡胶加工厂废水处理情况看,COD的去除率可达95%以上,出水水质稳定,可达标排放.运行成本为0.35元/m3,经济效益和环境效益都很显著. 相似文献
236.
Duchenne and Becker muscular dystrophy (D/BMD) are usually problematical when trying to determine the carrier status of at-risk women, which usually has to be based on haplotype or dosage analysis on Southern blots. Using multiplex polymerase chain reaction (PCR) analysis, we have detected deletions in 20 out of 44 D/BMD families with living affected members (45·5 per cent), more often in sporadic cases of DMD (14/22 with detectable deletion) than in familial ones (4/15), the majority (15/20) occurring in the distal region of the D/BMD gene. Four highly informative short tandem repeat polymorphisms (STRPs), which lie within the distal deletion hot spot of the D/BMD gene, can show loss of heterozygosity in carrier females, providing direct evidence of their carrier status. These STRPs greatly improve informativity, with a combined heterozygosity of 100 per cent and with the majority of families informative for three of the four STRPs. In 14/15 (93 per cent) of the families with distal deletions, the STRPs provided direct information on carrier status, and in some cases, they provide valuable information on recombination breakpoints and non-paternity. 相似文献
237.
We report the results of carrier and prenatal diagnosis for hypoxanthine guanine phosphoribosyltransferase (HPRT) deficiency, Lesch—Nyhan syndrome, by carrier testing of 83 women and prenatal analysis of 26 pregnancies. Our diagnostic methodologies include mutation detection and linkage analysis for probands and their families and biochemical measurement of HPRT enzyme activity for at-risk pregnancies. Identification of the mutation in the index case of each family permits precise carrier diagnosis using polymerase chain reaction (PCR) amplification of HPRT gene sequences and automated DNA sequencing. We demonstrate 100 per cent sensitivity for the detection of mutations in the HPRT gene of affected males and highly efficient carrier testing of at-risk females. Two other molecular methods proven to have high utility include PCR-based dosage analysis and linkage analysis by PCR amplification of a short tandem repeat (STR) in intron 3 of the HPRT gene. As a result, 45 at-risk women, 56 per cent of those tested, were identified not to be carriers of their family's HPRT gene mutation. Seven of these women were the mothers of affected males and prenatal testing for future pregnancies was recommended because of the possibility of gonadal mosaicism. Thirty-eight of these women were more distant relatives of affected males, thereby eliminating the need for future prenatal procedures. These studies illustrate the utility and precision of molecular methodologies for carrier and prenatal diagnosis of Lesch—Nyhan syndrome. These studies also illustrate that molecular diagnostic studies of affected males and carrier testing prior to pregnancy can clarify genetic risk predictions and eliminate unnecessary prenatal procedures. 相似文献
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239.
固定化啤酒酵母对241Am溶液吸附特性的研究 总被引:3,自引:0,他引:3
利用海藻酸钙包埋固定啤酒酵母,对放射性 241Am溶液进行吸附研究.结果表明在初始浓度为8.5 μg/L(1.08 MBq/L)的 241Am溶液中,pH1-4时固定化啤酒酵母吸附效果明显,吸附率在92%以上;接触2 h,吸附基本达到平衡;15~45℃范围内,温度对吸附行为无显著影响;固定化啤酒酵母重复吸附6次,其吸附率均大于90%,累积吸附量为0.5 μg/g(63.3 kBq/g);3次吸附后, 241Am溶液浓度可降为8.0×10 -5 μg/L(~10 Bq/L). 相似文献
240.