scholarly journals Проявление линии Видома при микроволновых измерениях увлажненных перекисью водорода сорбентов

Author(s):  
А.А. Гурулев ◽  
А.О. Орлов

For deeply supercooled bulk water, anomalies of thermodynamic values are known near the Widom line, the locus of increased fluctuations of entropy and density. In this work, we measured the reflected power of microwave radiation at a frequency of 18 GHz from a silicate sorbent sample moistened with a hydrogen peroxide solution. In the experiment, we observed variations in the recorded reflected radiation power in the range –46 – –47 °С, determined by structural changes in the liquid. Thus, it is shown that fluctuations of water parameters near the Widom line are manifested in changes not only in thermodynamic, but also in electrophysical quantities.

2009 ◽  
Vol 59 (12) ◽  
pp. 1400-1404
Author(s):  
Marius Tudorascu ◽  
Spiridon Oprea ◽  
Afrodita Doina Marculescu ◽  
Stefania Tudorascu

The mechanism of the enzymatic iodination process of diethylmaleate and diethylfumarate (which present no miscibility with water) in the presence of lactoperoxidase, both in diluted hydrogen peroxide solution and in a generating system of hydrogen peroxide using ammonium and calcium iodides as halide sources in disperse system (after an ultrasonic pretreatment) was studied. The obtained sole product (diethyl-2, 3-diiodosuccinate) after the enzymatic iodination process was directly hydrolyzed to a tartaric acid present in an optically inactive form. The mechanism of obtaining the intermediate and final products and respectively, the existence of both D, L-tartaric acid and meso-tartaric acids (as lithium bitartrates) were also investigated.


Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2876
Author(s):  
Napat Kaewtrakulchai ◽  
Kajornsak Faungnawakij ◽  
Apiluck Eiad-Ua

Oil palm male flowers (PMFs), an abundant agricultural waste from oil palm plantation in Thailand, have been utilized as an alternative precursor to develop nanoporous carbons (NPCs) via microwave-assisted pyrolysis combined potassium hydroxide (KOH) activation. The influences of relevant processing variables, such as activating agent ratio, microwave power, and activation time on the specific pore characteristics, surface morphology, and surface chemistry of PMFs derived nanoporous carbons (PMFCs) have been investigated to explore the optimum preparation condition. The optimum condition under a microwave radiation power of 700 W, activation holding time of 6 min, and activating agent ratio of 2:1 obtained the PMFC with the highest Brunauer–Emmett–Teller (BET) surface area and total pore volume approximately of 991 m2/g and 0.49 cm3/g, composed of a carbon content of 74.56%. Meanwhile, PMFCs have a highly microporous structure of about 71.12%. Moreover, activating agent ratio and microwave radiation power indicated a significant influence on the surface characteristics of PMFCs. This study revealed the potential of oil palm male flowers for the NPCs’ production via microwave-assisted KOH activation with a short operating-time condition.


PEDIATRICS ◽  
1990 ◽  
Vol 85 (4) ◽  
pp. 593-594
Author(s):  
WAYNE R. RACKOFF ◽  
DAVID F. MERTON

Gas embolism to the portal venous system is a well-recognized radiographic sign in infants with necrotizing enterocolitis. It also has been seen after colonic irrigation with hydrogen peroxide solution.1,2 We present what we believe is the first reported patient with radiographic evidence of portal venous gas embolism after ingestion of hydrogen peroxide solution. This finding is important because gas embolism to the portal venous system after colonic irrigation with hydrogen peroxide has been associated with gangrenous and perforated bowel.1,2 CASE REPORT A 2-year-old boy ingested an unknown amount of 3% hydrogen peroxide solution. The child was found with foam around his mouth.


Author(s):  
Juraj Michálek ◽  
Kseniya Domnina ◽  
Veronika Kvorková ◽  
Kristína Šefčovičová ◽  
Klaudia Mončeková ◽  
...  

Abstract The usage of the low-cost catalysts for methylene blue removal from wastewater was investigated. Heterogeneous Fenton-like process consists of the use of a hydrogen peroxide solution, and an iron-rich catalyst, red mud and black nickel mud were used for that purpose. The factors such as the catalyst dose and the hydrogen peroxide solution volume were monitored. The results of experiments showed that the degradation of methylene blue dye in Fenton-like oxidation process using selected catalysts can be described by a pseudo-second-order kinetic model. The highest dye removal efficiency (87.15 %) was achieved using the black nickel mud catalyst after 30 minutes of reaction.


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