砷胁迫下水磷耦合对不同磷效率水稻根表铁膜及其各部位砷含量的影响

为探索缓解水稻砷毒害的农艺措施,以耐低磷水稻99011和低磷敏感水稻99012为材料,通过土培试验,研究水分、磷用量及其交互作用对不同砷浓度酸性土壤中水稻根表铁膜以及植物体内砷分配的影响。结果表明,节水灌溉(干湿交替)明显减少水稻根表铁膜量,降低铁膜、根系、秸秆、颖壳和精米中的砷含量。与30mg·kg-1P2O5相比,180mg·kg-1P2O5能明显减少两个品种水稻的根表铁膜量以及根系和秸秆中的砷含量;对耐低磷品种铁膜砷含量影响不大,但显著降低磷敏感品种铁膜砷含量;在50mg·kg-1砷处理中增加磷用量对水稻颖壳砷含量影响不大,在100mg·kg-1砷处理时能显著降低颖壳砷含量;增加磷用量可明显增加耐低磷品种的精米砷含量,降低磷敏感品种的精米砷含量。水、磷交互效应主要受水分效应的影响。加砷处理后,相同处理下耐低磷品种的根表铁膜量和铁膜中的砷含量显著高于磷敏感品种,而根系、秸秆、颖壳和精米中的砷含量则相反。研究表明,可以通过节水灌溉,并根据砷污染程度和植物磷营养特性确定适当的磷肥用量,从而减少砷在水稻体内的累积,提高食品安全。     

大型水蚤生物检测系统对新农药速灭杀丁的毒性评价

速灭杀丁(Fenvalerate,Sumicidin 20％(?)C),又叫杀灭菊酯、戎酸氰醚酯、氰戎菊酯、S-5602。商品名叫来福灵,化学名称为a氰基-3-苯氧基苄基-2-(4-氯苯基)-3-甲基丁酸酯。化学结构式:     

Antibiotic and metal resistance of Stenotrophomonas maltophilia isolates from Eboling permafrost of the Tibetan Plateau

Environmental Science and Pollution Research - Whole-genome sequencing of pathogenic bacteria Stenotrophomonas maltophilia from a less polluted environment of permafrost can help understand the...     

淇河鲫生长激素全长cDNA的克隆与序列分析

采用RT-PCR法和3',5'RACE(Rapid amplification of cDNA ends)法从淇河鲫脑垂体RNA克隆出生长激素(Growthhormone,GH)cDNA.此cDNA全长1 191 nt[含Poly(A)14 nt],其5'端非编码区长55 nt,阅读框(Open reading frame,OAF)长633 nt,3'端非编码区长503 nt.由其推导的GH前体由210个氨基酸组成,其中氮端前22个氨基酸为信号肽部分.氨基酸序列比较表明,淇河鲫与同目的鲫鱼、鲤鱼、团头鲂和斑马鱼的同源性分别为98.6%、96.2%、91.5%和88.6%;与不同目的胡子鲇和鳗鲡的同源性分别为74.6%和49.5%;与哺乳类的家鼠和人等的同源性低于40%.图3参30     

生物法处理丙烯腈废气的初步研究

在对生物膜填料塔处理丙烯腈废气的研究中,分别考察了气相浓度、填料层高度、营养物、停留时间等操作参数对净化性能的影响． 通过试验发现,生物膜填料塔对丙烯腈废气具有良好的净化效果,阻力降为２９．４～４９Ｐａ,在进口浓度小于２０００ｍ ｇ／ｍ³,停留时间小于９０ｓ,高度大于２００ｍ ｍ 的填料层上,去除率达到９０％ 以上．     

Residues of carbosulfan and its metabolites carbofuran and 3-hydroxy carbofuran in rice field ecosystem in China

The fate of carbosulfan (seed treatment dry powder) was studied in rice field ecosystem, and a simple and reliable analytical method was developed for determination of carbosulfan, carbofuran, and 3-hydroxyl carbofuran in brown rice, rice straw, paddy water, and soil. The target compounds were extracted using acetonitrile or dichloromethane, cleaned up on acidic alumina or florisil solid phase extraction (SPE) cartridge, and analyzed by gas chromatography. The average recoveries of carbosulfan, carbofuran and 3-hydroxy carbofuran in brown rice, rice straw, paddy water, and soil ranged from 72.71% to 105.07%, with relative standard deviations of 2.00–8.80%. The limits of quantitation (LOQs) of carbosulfan, carbofuran and 3-hydroxy carbofuran in the samples (brown rice, rice straw, paddy water and soil) were 0.011, 0.0091, 0.014, 0.010 mg kg^?1, 0.016, 0.019, 0.025, 0.013 mg kg^?1, and 0.031, 0.039, 0.035, 0.036 mg kg^?1, respectively. The trials results showed that the half-lives of carbosulfan, carbofuran and 3-hydroxy carbofuran in rice straw were 4.0, 2.6 days, 3.9, 6.0 days, and 5.8, 7.0 days in Zhejiang and Hunan, respectively. Carbosulfan, carbofuran and 3-hydroxy carbofuran were detected in soils. Carbosulfan and 3-hydroxy carbofuran were almost undetectable in paddy water. Carbofuran was detected in paddy water. The final residues of carbosulfan, carbofuran and 3-hydroxy carbofuran in brown rice were lower than 0.05 mg kg^?1, which were lower than 0.5 mg kg^?1 (MRL of carbosulfan) or 0.1 mg kg^?1 (MRL of carbofuran). Therefore, a dosage of 420 g active ingredient per 100 kg seed was recommended, which could be considered as safe to human beings and animals. These would contribute to provide the scientific basis of using this insecticide.     

南淝河表层水中重金属空间分布、污染评价及来源

根据南淝河丰水期和枯水期水质的调查数据,采用单因子水质指数法和改进后的模糊综合评价法对水中重金属元素的污染进行了评价,确定了主要污染因子和优先控制断面,并利用主成分分析法对重金属污染进行了溯源分析。结果表明:Cr、Cu、Pb的含量平均值均为枯水期高于丰水期,而As、Cd的含量平均值均为枯水期低于丰水期。单因子水质指数法评价结果显示南淝河重金属污染的主要污染因子是Cd,丰水期和枯水期各采样点Cd的含量均达到地表水Ⅴ类水标准,最高值达到地表水Ⅴ类标准值的2.6倍。改进后模糊综合评价法评价结果显示南淝河水质丰水期基本属于地表水环境质量标准Ⅱ类水标准,潜山北路大桥断面污染最严重,属于优先控制断面,枯水期各断面水质均属于Ⅲ类水标准,整体上南淝河水质达到了水体功能区目标。主成分分析法结果显示,南淝河重金属污染的主要来源是流域内的农药化肥、机械制造和电镀行业的废水以及河道的行船。     

环境质量评价中关键污染因子的确定方法

介绍了几种在环境质量评价中关键污染因子的确定方法，在此基础上提出了一种新的关键污染因子的确定方法－－动态污染指数判别法。经过实例运用分析表明，该方法物理意义明确，简便易用。通过对某个时间段内污染物原始监测数据的灰色处理，从动态演变中找出关键因子，客观地判别各污染因子所起的作用，对各因子在下一个时间段的发展趋势作出预测判断，增加了评价的准确性。     

Fe3O4纳米磁性微粒对全氟辛烷磺酸盐的吸附

采用共沉淀法合成Fe3O4纳米磁性颗粒,用透射电子显微镜（TEM）、X射线衍射仪（XRD）以及振动样品磁强计（VSM）对Fe3O4纳米磁性颗粒的粒径、形貌和磁性进行表征并研究Fe3O4纳米磁性微粒对全氟辛磺酸盐的吸附。结果表明：在PFOS初始浓度4 mg/L,pH为3,反应时间24 h,Fe3O4纳米磁性微粒投加量1.25 g/L,对全氟辛磺酸盐去除率达到90%。Fe3O4纳米磁性微粒对PFOS的吸附符合Freundlich吸附方程。     

利用废啤酒酵母泥对活性黑31的吸附特性研究

利用粉末状废啤酒酵母泥对水中活性黑31进行吸附去除实验,研究了不同溶液初始pH值、不同温度对活性黑31的吸附性能,继而探讨了其吸附热力学和解吸性能。结果表明：在强酸条件下（pH 3）,废啤酒酵母泥对活性黑31的吸附量最大;温度对废啤酒酵母泥吸附活性黑31的性能影响不大,温度从25℃升至50℃,吸附量只减少了9.9 mg...