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101.
Cakirogullari GC  Secer S 《Chemosphere》2011,85(11):1713-1718
The concentrations of indicator polychlorinated biphenyls (PCBs) and organochlorine insecticides were determined in bonito (Sardasarda L. 1758) and anchovy (Engraulisencrasicolus L. 1758) from the Black Sea, Turkey. Concentrations of total indicator PCBs ranged between <1-17.0 in bonito, and <1-17.5 ng/g fresh weight in anchovy, and total of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane and its metabolites’ (DDTs) concentrations ranged between 13.4-26.3, and 2.96-19.0 ng/g fresh weight in bonito and anchovy respectively. PCB 52, p,p′-DDE and endosulfan (α + β) were found dominant in both of the fish species. Except endosulfan, and some DDT metabolites, none of the studied organochlorine pesticides was detected in the fish samples. Concentrations of PCBs in anchovy were found higher than those in bonito, whereas DDT and endosulfan concentrations were found similar in both of the fish species. All of the fish samples had residue concentrations below the maximum residue limits (MRL) recommended by FAO/WHO Codex Alimentarius Commission.  相似文献   
102.
反硝化除磷脱氮系统中DPB的驯化富集培养   总被引:2,自引:2,他引:0  
黄荣新  张杰  谌建宇 《环境科学》2010,31(5):1252-1256
反硝化同时脱氮除磷系统中反硝化除磷菌(DPB)的培养驯化状况,将直接影响污水中氮磷等营养元素的同时去除效率以及系统的高效稳定运行,为此本实验研究设计了一套以实际生活污水为处理对象的双污泥反硝化脱氮除磷工艺流程,采用逐渐过渡的培养方式,为DPB创造良好的厌氧/缺氧交替环境,即创造特定的适合DPB生存的环境条件让其进行自然选择,以筛选出来需要的DPB菌.结果表明,通过15d的间歇曝气的厌氧/好氧(A/O)运行方式可以对PAOs进行快速诱导;第二阶段,通过好氧曝气时间的逐渐减少,缺氧段投加硝酸氮的厌氧/好氧/缺氧(A/O/A)运行模式,25d左右可达到强化诱导反应器里面的DPB占PAOs的比例;最后让DPB在严格的厌氧/缺氧交替环境下进行富集培养19d,通过这种逐渐过渡培养的方式获得了对所需要的DPB菌的成功诱导富集,该菌的成功驯化培养为市政生活污水中的氮磷同时高效稳定去除提供了一种新方法.  相似文献   
103.
L-Cysteine has protective efficacy in cases of oxidative tissue injury. Sodium valproate is widely used as an anticonvulsant and an antidepressant in spite of hepatotoxicity as side effect. The aim of this study was to evaluate the protective role of L-cysteine in liver toxicity induced by sodium valproate overdose. Release of the hepatic enzymes, aspartate aminotransferase and alanine aminotransferase, and levels of lipid profiles, as well as the oxidative, enzymatic, and non-enzymatic antioxidant were assessed. Liver damage was judged histologically. L-Cysteine decreased the activity of alanine aminotransferase and aspartate aminotransferase, as well as improved the level of lipid profile, increased the enzymatic antioxidant (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase), and decreased the lipid peroxidation. L-Cysteine administration inhibited liver injury of sodium valproate.  相似文献   
104.
基于希瓦氏金属还原菌(Shewanella decolorationis S12)和针铁矿相互作用,讨论了蒽醌类有机质(AQS)对该针铁矿异化还原过程的调控机制.结果表明:AQS作为电子运移载体,使得还原解离态铁总量(Fetot)和可溶态铁含量(Fedis)均快速增加;不同含量的AQS加入前后,针铁矿还原平均速率得到显著上升,速率比在2.4~4.0之间,且该比值和AQS含量呈显著的线性关系,可决系数为0.9947.Fedis/Fetot比值随AQS含量升高而降低,当AQS含量由0.05 mmol·L-1增加至0.3 mmol·L-1时,Fedis/Fetot比值由0.935减小至0.705.Feads含量随AQS含量增加而增加,当体系中无AQS时,Feads含量维持在较低的水平(0.05 mmol·L-1).AQS参与下的铁异化还原过程实际上是由两个独立的子过程组成,即微生物呼吸作用驱动了AQS和还原态蒽二酚(AH2QS)的循环转变过程以及AH2QS进一步还原解离针铁矿的非生物过程.  相似文献   
105.
We fabricated and characterized two hybrid adsorbents originated from hydrated ferric oxides(HFOs) using a polymeric anion exchanger D201 and calcite as host. The resultant adsorbents(denoted as HFO-201 and IOCCS) were employed for Sb(V) removal from water. Increasing solution pH from 3 to 9 apparently weakened Sb(V) removal by both composites, while increasing temperature from 293 to 313 K only improved Sb(V) uptake by IOCCS. HFO-201 exhibited much higher capacity for Sb(V) than for IOCCS in the absence of other anions in solution. Increasing ionic strength from 0.01 to 0.1 mol/L NaNO3would result in a significant drop of the capacity of HFO-201 in the studied pH ranges; however, negligible effect was observed for IOCCS under similar conditions. Similarly, the competing chloride and sulfate pose more negative effect on Sb(V) adsorption by HFO-201 than by IOCCS, and the presence of silicate greatly decreased their adsorption simultaneously, while calcium ions were found to promote the adsorption of both adsorbents. XPS analysis further demonstrated that preferable Sb(V) adsorption by both hybrids was attributed to the inner sphere complexation of Sb(V) and HFO, and Ca(II) induced adsorption enhancement possibly resulted from the formation of HFO-Ca-Sb complexes. Column adsorption runs proved that Sb(V) in the synthetic water could be effectively removed from 30 μg/L to below 5 μg/L(the drinking water standard regulated by China), and the effective treatable volume of IOCCS was around 6 times as that of HFO-201, implying that HFO coatings onto calcite might be a more effective approach than immobilization inside D201.  相似文献   
106.
Microcystin-RR (MC-RR) has been suggested to induce apoptosis in tobacco BY-2 cells through mitochondrial dysfunction including the loss of mitochondrial membrane potential . TO further elucidate the mechanisms involved in MC-RR induced apoptosis in tobacco BY-2 cells, we have investigated the role of mitochondrial electron transport chain (ETC) as a potential source for reactive oxygen species (ROS). Tobacco BY-2 cells after exposure to MC-RR (60 mg/L) displayed apoptotic changes in association with an increased production of ROS and loss of Am. All of these adverse effects were significantly attenuated by ETC inhibitors including Rotenone (2 μmol/L, complex I inhibitor) and antimycin A (0.01 μmol/L, complex III inhibitor), but not by thenoyltrifluoroacetone (S μmol/L, complex Ⅱinhibitor). These results suggest that rnitochondrial ETC plays a key role in mediating MC-RR induced apoptosis in tobacco BY-2 cells through an increased mitochondrial production of ROS.  相似文献   
107.
1997年建成的"新疆环境保护"网站是全国第一家环保门户网站,也是新疆第一家政府类网站,新疆环保网站建设与发展已经历风雨兼程的10a,现在正进入一个崭新的发展阶段.回顾、总结和展望新疆各级环保网站的发展,吸取发展中的经验与教训,探索新疆各级环保网站建设中的规律,对新疆环保电子政务的"理性建设、快速推进"大有裨益.  相似文献   
108.
废水同步生物处理与生物燃料电池发电研究   总被引:27,自引:10,他引:17  
尤世界  赵庆良  姜珺秋 《环境科学》2006,27(9):1786-1790
利用厌氧活性污泥作为接种体成功地启动了空气阴极生物燃料电池(ACMFC),110h的接种产生了0.24V的电压;以乙酸钠和葡萄糖作底物分别产生了0.38V和0.41V电压(外电阻1 000Ω),最大功率密度分别达到146.56 mW/m2和192.04mW/m2,表明有机废水可以用来发电;同时,乙酸钠和葡萄糖的去除率分别为99%和87%,表明燃料电池可以处理废水.二者的电子回收率均在10%左右,主要是由于阴极对氧气分子的透过作用引起的微生物好氧呼吸导致电子损失.  相似文献   
109.
Traditional pesticides (TP) often do not adhere tightly to crop foliage. They can easily enter the surrounding environment through precipitation and volatilization. This can result in the pollution of the surrounding soil, water, and air. To reduce pesticide pollution, we developed a loss-control pesticide (LCP) by adding attapulgite with a nano networks structure fabricated using high energy electron beam (HEEB) irradiation and hydrothermal treatment to TP. HEEB irradiation effectively dispersed originally aggregated attapulgite through modified thermal, charge, and physical effects. Hydrothermal treatment further enhanced the dispersion of attapulgite to form nano porous networks via thermal and wet expansion effects, which are beneficial for pesticide binding. An LCP has improved retention on crop leaf surfaces. It has a higher adhesion capacity, reduced leaching and volatilization, and extended residual activity compared with the TP formulation. The treatment increases the residual activity of pesticides on crop foliage and decreases environmental pollution.  相似文献   
110.
Alginic acid and metal alginates are prepared from fresh algae using extraction method. A FTIR spectrum indicates that alginic acid is converted into the metal alginate. Comparing calcium and cobalt alginates, asymmetric stretching of free carboxyl group of calcium alginate at 1630 cm−1 is shifted to 1585 cm−1 in cobalt alginate, due to the change of charge density, radius and atomic weight of the cation, creating a new environment around the carbonyl group. The strong exothermic peak of alginic acid in DSC thermogram indicates the decomposition of biopolymer, whereas strong exothermic peak of metal alginate in DSC thermogram attributed to the decomposition of biopolymer and formation of respective carbonate. Based on DSC study, the decomposition of cobalt alginate occurs at higher temperature comparing to those of sodium and calcium alginate, which may conclude into the higher stability of cobalt alginate. TGA results reveal that, cobalt alginate is more stable than calcium and sodium alginate at 300 °C temperature. Surface morphology (at same magnification), as well as porosity (%) and pore size distribution results change with metals present in different metal alginates.  相似文献   
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