A novel induced zero-valent iron electrode for in-situ slow release of Fe2+ to effectively trigger electro-Fenton oxidation under neutral pH condition: Advantages and mechanisms

2021 ◽  
pp. 120160
Author(s):  
Xiaodong Ma ◽  
Tiantong Rao ◽  
Mingchen Zhao ◽  
Zhiwei Jia ◽  
Gengbo Ren ◽  
...  
Keyword(s):  
Slow Release ◽  
Fenton Oxidation ◽  
Zero Valent Iron ◽  
Iron Electrode ◽  
Neutral Ph

Treating Methyl Orange in a Two-Dimensional Flow Tank by In Situ Chemical Oxidation Using Slow-Release Persulfate Activated with Zero-Valent Iron

2015 ◽  
Vol 32 (12) ◽  
pp. 1007-1015 ◽  
Author(s):  
Chanat Chokejaroenrat ◽  
Chainarong Sakulthaew ◽  
Tunlawit Satapanajaru ◽  
Thanakorn Tikhamram ◽  
Alongkon Pho-Ong ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Slow Release ◽  
Chemical Oxidation ◽  
Zero Valent Iron ◽  
Two Dimensional ◽  
In Situ Chemical Oxidation ◽  
Dimensional Flow ◽  
Two Dimensional Flow

Reduction of adsorbable organically bound halogens (AOX) formation at near-neutral pH chlorine dioxide bleaching of softwood kraft pulp

Holzforschung ◽  
2020 ◽  
Vol 74 (6) ◽  
pp. 597-604
Author(s):  
Sara Starrsjö ◽  
Olena Sevastyanova ◽  
Peter Sandström ◽  
Juha Fiskari ◽  
Maria Boman ◽  
...  
Keyword(s):  
Chlorine Dioxide ◽  
High Selectivity ◽  
Bicarbonate Buffer ◽  
Neutral Ph ◽  
Elemental Chlorine ◽  
Pulp Viscosity ◽  
Softwood Kraft Pulp ◽  
New Type ◽  
Adsorbable Organically Bound Halogens

AbstractRecently, a new type of bleaching sequence, Elemental Chlorine Free (ECF) light with one D stage, has been developed. It combines the efficiency and high selectivity of chlorine dioxide (ClO2) bleaching with more environmental friendly oxygen based bleaching chemicals. This work examines the effect of pH on the formation of adsorbable organically bound halogens (AOX) in an intermediate D stage – a single ClO2 stage at the middle of an ECF light bleaching sequence. Carbon dioxide (CO2) is used to generate a bicarbonate buffer in situ, stabilizing the pH during the bleaching. Near-neutral pH is hypothesized to decrease the formation of strongly chlorinating species, so that the AOX formation is reduced. The results indicate that a near-neutral pH D stage can reduce the AOX content in the effluents with up to 30%. The ISO brightness was unchanged to a lower ClO2 consumption. The pulp viscosity was slightly higher after near-neutral pH D stage, but to its disadvantage a lesser delignification and removal of HexA was obtained. The degradation of HexA correlated well with the AOX, affirming earlier theories that HexA has a major impact on the AOX formation. The higher amounts of residual HexA and lignin resulted in more thermal yellowing of the pulps bleached with a near-neutral pH D stage.

An in situ carbon-grafted alkaline iron electrode for iron-based accumulators

2014 ◽  
Vol 7 (3) ◽  
pp. 1110 ◽  
Author(s):  
Aravamuthan Sundar Rajan ◽  
Srinivasan Sampath ◽  
Ashok Kumar Shukla
Keyword(s):  
Iron Electrode ◽  
Iron Based

Regulated expression and growth inhibitory effects of transforming growth factor-beta isoforms in mouse mammary gland development

Development ◽  
1991 ◽  
Vol 113 (3) ◽  
pp. 867-878 ◽  
Author(s):  
S.D. Robinson ◽  
G.B. Silberstein ◽  
A.B. Roberts ◽  
K.C. Flanders ◽  
C.W. Daniel
Keyword(s):  
Gene Expression ◽  
Mammary Gland ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Slow Release ◽  
Mouse Mammary Gland ◽  
Tgf Beta ◽  
Growth Factor Beta ◽  
Beta 2

Transforming Growth Factor-beta 1 (TGF-beta 1) was previously shown to inhibit reversibly the growth of mouse mammary ducts when administered in vivo by miniature slow-release plastic implants. We now report a comparative analysis of three TGF-beta isoforms with respect to gene expression and localization of protein products within the mouse mammary gland. Our studies revealed overlapping expression patterns of TGF-beta 1, TGF-beta 2 and TGF-beta 3 within the epithelium of the actively-growing mammary end buds during branching morphogenesis, as well as within the epithelium of growth-quiescent ducts. However, TGF-beta 3 was the only isoform detected in myoepithelial progenitor cells (cap cells) of the growing end buds and myoepithelial cells of the mature ducts. During pregnancy, TGF-beta 2 and TGF-beta 3 transcripts increased to high levels, in contrast to TGF-beta 1 transcripts which were moderately abundant; TGF-beta 2 was significantly transcribed only during pregnancy. Molecular hybridization in situ revealed overlapping patterns of expression for the three TGF-beta isoforms during alveolar morphogenesis, but showed that, in contrast to the patterns of TGF-beta 1 and TGF-beta 2 expression, TGF-beta 3 is expressed more heavily in ducts than in alveoli during pregnancy. Developing alveolar tissue and its associated ducts displayed striking TGF-beta 3 immunoreactivity which was greatly reduced during lactation. All three isoforms showed dramatically reduced expression in lactating tissue. The biological effects of active, exogenous TGF-beta 2 and TGF-beta 3 were tested with slow-release plastic implants. These isoforms, like TGF-beta 1, inhibited mammary ductal elongation in situ by causing the disappearance of the proliferating stem cell layer (cap cells) and rapid involution of ductal end buds. None of the isoforms were active in inhibiting alveolar morphogenesis. We conclude that under the limited conditions of these tests, the three mammalian isoforms are functionally equivalent. However, striking differences in patterns of gene expression and in the distribution of immunoreactive peptides suggest that TGF-beta isoforms may have distinct roles in mammary growth regulation, morphogenesis and functional differentiation.

scholarly journals In Situ EPR Characterization of a Cobalt Oxide Water Oxidation Catalyst at Neutral pH

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 926 ◽  
Author(s):  
Yury Kutin ◽  
Nicholas Cox ◽  
Wolfgang Lubitz ◽  
Alexander Schnegg ◽  
Olaf Rüdiger
Keyword(s):  
Cobalt Oxide ◽  
Water Oxidation ◽  
Large Scale ◽  
Low Cost ◽  
Operating Conditions ◽  
Oxidation Catalyst ◽  
O2 Evolution ◽  
Ligand Field ◽  
Neutral Ph

Here we report an in situ electron paramagnetic resonance (EPR) study of a low-cost, high-stability cobalt oxide electrodeposited material (Co-Pi) that oxidizes water at neutral pH and low over-potential, representing a promising system for future large-scale water splitting applications. Using CW X-band EPR we can follow the film formation from a Co(NO3)2 solution in phosphate buffer and quantify Co uptake into the catalytic film. As deposited, the film shows predominantly a Co(II) EPR signal, which converts into a Co(IV) signal as the electrode potential is increased. A purpose-built spectroelectrochemical cell allowed us to quantify the extent of Co(II) to Co(IV) conversion as a function of potential bias under operating conditions. Consistent with its role as an intermediate, Co(IV) is formed at potentials commensurate with electrocatalytic O2 evolution (+1.2 V, vs. SHE). The EPR resonance position of the Co(IV) species shifts to higher fields as the potential is increased above 1.2 V. Such a shift of the Co(IV) signal may be assigned to changes in the local Co structure, displaying a more distorted ligand field or more ligand radical character, suggesting it is this subset of sites that represents the catalytically ‘active’ component. The described spectroelectrochemical approach provides new information on catalyst function and reaction pathways of water oxidation.

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