scholarly journals Application and mechanism of ferrihydrite in the EDDS improved heterogeneous photo-Fenton system: the role of different reactive species under different conditions

2020 ◽  
Vol 44 (18) ◽  
pp. 7602-7610
Author(s):  
Hongjie Xie ◽  
Mengqi Luo ◽  
Wenyu Huang ◽  
Ying Huang ◽  
Xiaoqing Feng ◽  
...  

The application of carboxylic acid and natural iron oxide in heterogeneous AOP systems for the treatment of organic pollutants in water has attracted extensive attention.

1969 ◽  
Vol 21 (02) ◽  
pp. 294-303 ◽  
Author(s):  
H Mihara ◽  
T Fujii ◽  
S Okamoto

SummaryBlood was injected into the brains of dogs to produce artificial haematomas, and paraffin injected to produce intracerebral paraffin masses. Cerebrospinal fluid (CSF) and peripheral blood samples were withdrawn at regular intervals and their fibrinolytic activities estimated by the fibrin plate method. Trans-form aminomethylcyclohexane-carboxylic acid (t-AMCHA) was administered to some individuals. Genera] relationships were found between changes in CSF fibrinolytic activity, area of tissue damage and survival time. t-AMCHA was clearly beneficial to those animals given a programme of administration. Tissue activator was extracted from the brain tissue after death or sacrifice for haematoma examination. The possible role of tissue activator in relation to haematoma development, and clinical implications of the results, are discussed.


1992 ◽  
Vol 25 (11) ◽  
pp. 403-410 ◽  
Author(s):  
B. E. Rittmann

Microbiological detoxification of hazardous organic pollutants is highly promising, but its reliable implementation requires a sophisticated understanding of several different substrate types and how they interact. This paper carefully defines the substrate types and explains how their interactions affect the bacteria's electron and energy flows, information flow, and degradative activity. For example, primary substrates, which are essential for growth and maintenance of the bacteria, also interact with degradation of specific hazardous pollutants by being inducers, inhibitors, and direct or indirect cosubstrates. The target contaminants, which often are secondary substrates, also have the interactive roles of self-inhibitor, inhibitor of primary-substrate utilization, inducer, and a part of an aggregate primary substrate.


1995 ◽  
Vol 31 (1) ◽  
pp. 61-70 ◽  
Author(s):  
Graham F. White

Many organic pollutants, especially synthetic surfactants, adsorb onto solid surfaces in natural and engineered aquatic environments. Biofilm bacteria on such surfaces make major contributions to microbial heterotrophic activity and biodegradation of organic pollutants. This paper reviews evidence for multiple interactions between surfactants, biodegradative bacteria, and sediment-liquid interfaces. Biodegradable surfactants e.g. SDS, added to a river-water microcosm were rapidly adsorb to sediment surface and stimulated the indigenous bacteria to attach to the sediment particles. Recalcitrant surfactants and non-surfactant organic nutrients did not stimulate attachment Attachment of bacteria was maximal when biodegradation was fastest, and was reversed when biodegradation was complete. Dodecanol, the primary product of SDS-biodegradation, markedly stimulated attachment. When SDS was added to suspensions containing sediment and either known degraders or known non-degraders, only the degraders became attached, and attachment accelerated surfactant biodegradation to dodecanol. These cyclical cooperative interactions have implications for the design of biodegradability-tests, the impact of surfactant adjuvants on biodegradability of herbicides/pesticides formulated with surfactants, and the role of surfactants used to accelerate bioremediation of hydrocarbon-polluted soils.


Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 999 ◽  
Author(s):  
Aranza Denisse Vital-Grappin ◽  
Maria Camila Ariza-Tarazona ◽  
Valeria Montserrat Luna-Hernández ◽  
Juan Francisco Villarreal-Chiu ◽  
Juan Manuel Hernández-López ◽  
...  

Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate MPs pollution in an environmentally friendly process, we propose using a photocatalytic process that can easily be implemented in wastewater treatment plants (WWTPs). As photocatalysis involves the formation of reactive species such as holes (h+), electrons (e−), hydroxyl (OH●), and superoxide ion (O2●−) radicals, it is imperative to determine the role of those species in the degradation process to design an effective photocatalytic system. However, for MPs, this information is limited in the literature. Therefore, we present such reactive species’ role in the degradation of high-density polyethylene (HDPE) MPs using C,N-TiO2. Tert-butanol, isopropyl alcohol (IPA), Tiron, and Cu(NO3)2 were confirmed as adequate OH●, h+, O2●− and e− scavengers. These results revealed for the first time that the formation of free OH● through the pathways involving the photogenerated e− plays an essential role in the MPs’ degradation. Furthermore, the degradation behaviors observed when h+ and O2●− were removed from the reaction system suggest that these species can also perform the initiating step of degradation.


Nano Select ◽  
2021 ◽  
Author(s):  
Ramis Arbi ◽  
Amr Ibrahim ◽  
Liora Goldring‐Vandergeest ◽  
Kunyu Liang ◽  
Greg Hanta ◽  
...  

2021 ◽  
Vol 165 ◽  
pp. 54
Author(s):  
Patricia de la Cruz-Ojeda ◽  
M. Ángeles Rodríguez-Hernández ◽  
Elena Navarro-Villarán ◽  
Paloma Gallego ◽  
Pavla Staňková ◽  
...  

2007 ◽  
Vol 21 (05) ◽  
pp. 731-736
Author(s):  
V. SIMON ◽  
P. RIEDL ◽  
E. TATARU

Glass stability and the structural role of iron oxide in x Fe 2 O 3(100-x)[ B 2 O 3– MO ] systems ( M=Ca , Sr or Ba , 0≤x≤30 mol%) were estimated from differential thermal analysis. The results suggest structural changes characteristic for the transition from short range to intermediate range order as the cationic field strength of the alkaline earths increases. In contrast, the iron addition has an opposite effect and determines a higher glass stability of these systems.


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