响应面法优化黄粉虫幼虫处理餐厨垃圾饲养条件的研究

研究了黄粉虫幼虫处理餐厨垃圾的方法.首先在饲养温度、饲料含水量和饲养密度等条件下进行单因素实验,然后,以利用率为指标,运用响应面法优化了黄粉虫幼虫处理餐厨垃圾的饲养条件,结果表明,最佳饲养条件为饲养温度26.7℃、饲料含水量14.5％、饲养密度4.1头/cm2.在此饲养条件下,黄粉虫对餐厨垃圾利用率理论值为38.72％,实际餐厨垃圾利用率为38.88％,相对误差为0.41％,说明利用黄粉虫幼虫处理餐厨垃圾具有较好的效果.     

Bioconcentration and half-life of quinalphos pesticide in rice-fish integration system in the Mekong Delta,Vietnam

In order to determine the distribution and enable the elimination of quinalphos, a popular active pesticide compound used in the Mekong Delta, an experiment was set up in a rice-fish integration system in Can Tho City, Vietnam. Fish was stocked into the field when the rice was two-months old. Quinalphos was applied twice in doses of 42.5 g per 1000 m². Water, fish and sediment samples were collected at time intervals and analyzed by a Gas Chromatography Electron Capture Detector system. The results show that quinalphos residues in fish muscles were much higher than those of the water and the bioconcentration factor (logBCF) was above 2 for the fish. The half-life of first and second quinalphos applications were 12.2 and 11.1 days for sediment, 2.5 and 1.1 days for silver barb, 1.9 and 1.3 days for common carp, and 1.1 and 1.0 days for water, respectively.     

Oxidation of ofloxacin by Oxone/Co2+: identification of reaction products and pathways

Oxidative degradation of ofloxacin (OFX) by sulfate free radicals (SO₄ ^??) in the UV/Oxone/Co²⁺oxidation process was investigated for the first time, with a special focus upon identifying the transformation products as well as understanding the reaction pathways. Thirteen main compounds were identified after the initial transformation of OFX; the detailed structural information of which were characterized by high-performance liquid chromatography–high resolution mass spectrometry and MS fragmentation analysis. The degradation pathways mainly encompassed ring openings at both the piperazinyl substituent and the quinolone moiety, indicating that the usage of SO₄ ^?? aided the oxidative degradation of OFX to undergo more facile routes compared to those in previous reports by using OH^?/h⁺ as the oxidant, where the initial transformation attacks were mainly confined to the piperazine moiety. Moreover, in this study, smart control over the pH conditions of the oxidation system via different modes of Oxone dosage resulted in the selective degradation of the functional sites of OFX molecule, where it was shown that the SO₄ ^??-driven destruction of the quinolone moiety of OFX molecule favored the neutral pH conditions. This would be beneficial for the reduction of bacterial resistance against quinolones in the aqueous environment.     

Polychlorinated naphthalenes (PCNs) in riverine and marine sediments of the Laizhou Bay area, North China

PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g⁻¹ dry weight (dw) with a mean value of 1.1 ng g⁻¹ dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors.     

Levels and distribution of Dechlorane Plus in coastal sediments of the Yellow Sea, North China

Dechlorane Plus (DP) has been determined in surface sediments from three Chinese coastal bays, e.g. Jiaozhou, Sishili and Taozi Bay in North China. DP concentrations ranged from <1.2 to 187 pg g⁻¹ dry weight (dw) (mean: 24.7 pg g⁻¹ dw) in Jiaozhou Bay, <1.2 to 135 pg g⁻¹ dw (mean 69.9 pg g⁻¹ dw) in Sishili Bay and <1.2 to 66.7 pg g⁻¹ dw (mean: 40.4 pg g⁻¹ dw) in Taozi Bay, respectively. Additionally, two dechlorinated species were quantified, which accounted for 0.6-5.1% of the ∑DP concentration.The f_syn values (syn-isomer/(syn- + anti-isomer)) in sediments from Jiaozhou Bay (mean 0.29) were close to the technical DP mixture (0.2-0.4), probably indicating local inputs of DP. In contrast, sediments in Sishili and Taozi Bay showed much lower f_syn values (mean 0.16). During transportation the DP isomers are subject to stereo selective degradation which partly resulted in the relative enrichment of anti-DP in coastal sediments.     

GIS罐体内部异物清理机器人的研发与应用

针对气体绝缘金属封闭开关设备( gas insulated switchgear, GIS)内部异物颗粒引起设备内部电场畸变,从而造成设备闪络故障问题,通过对异物颗粒的产生原因及影响因素进行分析,研制了一种GIS罐体内部异物颗粒清理机器人,实现了GIS设备内部可视化异物清理功能。应用结果表明:机器人检测不仅提高了750kV GIS内部缺陷检查的效率,而且保证了检测人员的安全,为GIS状态检修提供了有效技术支持。     

稀有鮈鲫成体神经发生相关基因的分子克隆及序列分析

成体神经发生是脊椎动物中广泛存在的一种生物学特征。成体硬骨鱼类的脑展现出强烈的神经活性以及出色的脑修复能力,这使得硬骨鱼类成为研究成体神经发生和脑修复的一个理想的模型。本文克隆了成体稀有鮈鲫(Gobiocypris rarus)脑组织中神经发生及脑修复相关的hes5、pax6、sox11和prox1基因的部分c DNA序列并进行了序列分析。序列分析结果表明,pax6和sox11基因片段与斑马鱼(Danio rerio)对应的基因片段的同源性最高,分别为97%和94%;hes5基因与鲤鱼(Cyprinus carpio)相对应的基因片段的同源性最高,为92%;prox1基因在物种间的同源性最低。基于稀有鮈鲫和已知物种相应基因的核苷酸序列构建了系统发育树,发现稀有鮈鲫prox1基因与其他硬骨鱼类的亲缘关系最远。本文为进一步开展神经毒性类化学品对水生生物鱼类的成体神经毒性作用机制研究提供了分子生物学基础。     

Fenton 法降解抗生素磺胺间甲氧嘧啶钠

应用Fenton高级氧化技术降解水溶液中抗生素磺胺间甲氧嘧啶钠(SMMS),系统探讨了起始pH、CSMMS、CFe2+、CH2O2和温度等因素对SMMS降解效果的影响。结果表明:CSMMS=4.53 mg/L,pH=4.0,CH2O2=0.49 mmol/L,CFe2+=19.51μmol/L,T=25℃为最佳反应条件。在最佳条件下,87.4%的SMMS可以在120 min内降解。反应动力学研究表明Fenton氧化降解SMMS分为两个阶段,快速反应阶段和慢速反应阶段,并建立了两阶段动力学模型,模型拟合结果较好。研究结果为含有SMMS的污废水处理提供了基础数据和科学参考。     

Facile, effective, and environment-friendly degradation of sulfamonomethoxine in aqueous solution with the aid of a UV/Oxone oxidative process

The degradation of sulfamonomethoxine (SMM) in the aqueous environment by the combination of UV illumination and Oxone has been studied. Experimental results indicated that the UV illumination can effectively activate Oxone to produce sulfate-free radicals (SO₄ ^??). When 10 mmol L^?1 Oxone was added, 96.78 % removal of SMM (5 mg L^?1) was achieved within 90 min. Mineralization of SMM was investigated by measuring the total organic carbon, which decreased by 89.01 % after 90 min reaction. Six intermediate compounds generated during the SMM degradation were identified with the aid of liquid chromatography and mass spectroscopy, combined with proton nuclear magnetic resonance spectroscopy. A general reaction pathway for the degradation of SMM was proposed, where the presence of SO₄ ^?? remained crucial during the degradation process.