H2O2 production rate in Lactobacillus johnsonii is modulated via the interplay of a heterodimeric flavin oxidoreductase with a soluble 28 Kd PAS domain containing protein

Wet Spun PEDOT/CNT Composite Hollow Fibers as Flexible Electrodes for H2O2 Production

10.31224/osf.io/jgzne ◽

2021 ◽

Author(s):

Matthias Wessling

Keyword(s):

Hydrogen Peroxide ◽

Production Rate ◽

Electrode Materials ◽

Hollow Fibers ◽

H2o2 Production ◽

Composite Electrodes ◽

High Production Rate ◽

High Production ◽

Continuous Fabrication ◽

First Time

The electrochemical synthesis of hydrogen peroxide (H2O2) using the oxygen reduction reaction (ORR) requires highly catalytic active, selective, and stable electrode materials to realize a green and efficient process. The present publication shows for the first time the application of a facile one-step bottom-up wet-spinning approach for the continuous fabrication of stable and flexible tubular poly(3,4-ethylene dioxythiophene) (PEDOT : PSS) and PEDOT : PSS/carbon nanotube (CNT) hollow fibers. Additionally, electrochemical experiments reveal the catalytic activity of acid-treated PEDOT : PSS and its composites in the ORR forming hydrogen peroxide for the first time. Under optimized conditions, the composite electrodes with 40 wt % CNT loading could achieve a high production rate of 0.01 mg/min/cm2 and a current efficiency of up to 54 %. In addition to the high production rate, the composite hollow fiber has proven its long-term stability with 95 % current retention after 20 h of hydrogen peroxide production.

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Photoelectrocatalytic H2 and H2O2 Production Using Visible-Light-Absorbing Photoanodes

Catalysts ◽

10.3390/catal9030243 ◽

2019 ◽

Vol 9 (3) ◽

pp. 243 ◽

Cited By ~ 7

Author(s):

Ioannis Papagiannis ◽

Elias Doukas ◽

Alexandros Kalarakis ◽

George Avgouropoulos ◽

Panagiotis Lianos

Keyword(s):

Hydrogen Peroxide ◽

Visible Light ◽

Production Rate ◽

Carbon Film ◽

Solar Fuels ◽

H2o2 Production ◽

Carbon Cloth ◽

Electrocatalytic Reduction ◽

Hydrogen Peroxide Production ◽

The Difference

Hydrogen and hydrogen peroxide have been photoelectrocatalytically produced by electrocatalytic reduction using simple carbon electrodes made by depositing a mesoporous carbon film on carbon cloth. Visible-light-absorbing photoanodes have been constructed by depositing mesoporous CdS/TiO2 or WO3 films on transparent fluorine-doped tin oxide (FTO) electrodes. Both produced substantial photocurrents of up to 50 mA in the case of CdS/TiO2 and 25 mA in the case of WO3 photoanodes, and resulting in the production of substantial quantities of H2 gas or aqueous H2O2. Maximum hydrogen production rate was 7.8 µmol/min, and maximum hydrogen peroxide production rate was equivalent, i.e., 7.5 µmol/min. The same reactor was employed for the production of both solar fuels, with the difference being that hydrogen was produced under anaerobic and hydrogen peroxide under aerated conditions. The present data promote the photoelectrochemical production of solar fuels by using simple inexpensive materials for the synthesis of catalysts and the construction of electrodes.

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Dry chip feedrate control using online chip moisture

TAPPI Journal ◽

10.32964/tj17.05.295 ◽

2018 ◽

Vol 17 (05) ◽

pp. 295-305

Author(s):

Wesley Gilbert ◽

Ivan Trush ◽

Bruce Allison ◽

Randy Reimer ◽

Howard Mason

Keyword(s):

Production Rate ◽

Control Strategy ◽

Rate Control ◽

Near Infrared ◽

Dry Mass ◽

The Other ◽

Process Variability ◽

Moisture Sensor ◽

Feedback Control Strategy ◽

And Control

Normal practice in continuous digester operation is to set the production rate through the chip meter speed. This speed is seldom, if ever, adjusted except to change production, and most of the other digester inputs are ratioed to it. The inherent assumption is that constant chip meter speed equates to constant dry mass flow of chips. This is seldom, if ever, true. As a result, the actual production rate, effective alkali (EA)-to-wood and liquor-to-wood ratios may vary substantially from assumed values. This increases process variability and decreases profits. In this report, a new continuous digester production rate control strategy is developed that addresses this shortcoming. A new noncontacting near infrared–based chip moisture sensor is combined with the existing weightometer signal to estimate the actual dry chip mass feedrate entering the digester. The estimated feedrate is then used to implement a novel feedback control strategy that adjusts the chip meter speed to maintain the dry chip feedrate at the target value. The report details the results of applying the new measurements and control strategy to a dual vessel continuous digester.

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CORTICOSTEROID-UMSATZ UND CORTICOSTEROID-PRODUKTION BEI RATTEN UNTER DER BEHANDLUNG MIT ANABOLEN STEROIDEN

Acta Endocrinologica ◽

10.1530/acta.0.0480263 ◽

1965 ◽

Vol 48 (2) ◽

pp. 263-271 ◽

Cited By ~ 8

Author(s):

Herbert Schriefers ◽

Gerlinde Scharlau ◽

Franzis Pohl

Keyword(s):

Production Rate ◽

Adult Female ◽

Anabolic Steroids ◽

Reduction Rate ◽

Female Rats ◽

Adrenal Weight ◽

Hydrogenase Activity ◽

Anabolic Effect ◽

Liver Slices

ABSTRACT After the administration of anabolic steroids to adult female rats in daily doses of 1 mg per animal for 14 days, the following parameters were investigated: the rate of the Δ4-5α-hydrogenase-catalyzed cortisone reduction in liver slices and microsomal fractions, the adrenal weight and the in vitro corticosterone production rate. Among the steroids tested, only 17α-methyl-testosterone and 17α-ethyl-19-nor-testosterone were effective in lowering significantly cortisone reduction rate by liver slices with concomitant decreases in microsomal Δ4-5α-hydrogenase-activity. Testosterone, 19-nor-testosterone, 17α-ethinyl-19-nor-testosterone, 17α-methyl-17β-hydroxy-androsta-1,4-dien-3-one and 1-methyl-17β-hydroxy-androst-1-en-3-one were ineffective or only slightly effective. Adrenal weight and absolute corticosterone production rate (μg/60 min per animal) were decreased after treatment with 17α-methyl-testosterone, 17α-ethyl-19-nor-testosterone and 1-methyl-17β-hydroxy-androst-1-en-3-one. Corticosterone production was decreased with 17α-ethinyl-19-nor-testosterone in spite of an unchanged adrenal weight. The relative corticosterone production rate (μg/60 min · 100 mg adrenal) was in any cases unaffected. According to these results there exists – with the exception of 17α-ethinyl-19-nor-testosterone – a strict parallelism between corticosteroid turnover and corticosterone production rate: unchanged turnover is correlated with unchanged corticosterone production rate, while a decreased turnover is correlated with decreased adrenal activity. The protein-anabolic effect of certain anabolic steroids may be partly due to an anti-catabolic action of these compounds resulting from a decreased corticosteroid inactivation and production rate. Possible mechanisms by which anabolic steroids may affect corticosteroid-balance are discussed.

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VARIATION OF CORTISOL METABOLISM AS A CONTRIBUTING FACTOR TO DISCREPANCIES IN THE MEASUREMENT OF CORTISOL PRODUCTION RATE

Acta Endocrinologica ◽

10.1530/acta.0.0700089 ◽

1972 ◽

Vol 70 (1) ◽

pp. 89-96 ◽

Cited By ~ 2

Author(s):

M. J. Levell

Keyword(s):

Production Rate ◽

Isotope Dilution ◽

Normal Subjects ◽

Contributory Factor ◽

Morning Dose ◽

Production Rates ◽

Evening Dose ◽

Cortisol Metabolism

ABSTRACT Five normal subjects were given [14C] cortisol in the morning and [3H] cortisol in the evening, in both cases by mouth. The excretion of radioactivity in tetrahydrocortisol (THF) and tetrahydrocortisone (THE) was measured by a modified form of reverse isotope dilution. In 2 subjects, the ratio of isotopic THF/isotopic THE was higher after the evening dose than after the morning dose. In 1 subject the ratio decreased. In 2 subjects it did not change. Cortisol production rates calculated from THF were usually higher than those calculated from THE. The observed variations of metabolism were only a contributory factor to these discrepancies.

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