scholarly journals Isolation, Definition and Chemical Control some of the Bacteria that Cause Contamination of Wall Paintings in Caves

1970 ◽  
Vol 7 (5) ◽  
pp. 6-11
Author(s):  
Fatma. M. A El-Gorj ◽  
M. A. Aisha ◽  
W.O. Maznah
Keyword(s):  
Hydrogen Peroxide ◽  
Sodium Hypochlorite ◽  
Chemical Method ◽  
Dna Polymorphisms ◽  
Gram Negative Bacteria ◽  
Wall Paintings ◽  
Laboratory Studies ◽  
Calcium Hypochlorite ◽  
Blast Search ◽  
Niah Cave

Background: Caves are unique natural features and habitats where specialized organisms grow. One of the world’s main concerns is that of the conservation and preservation of our cultural heritage, including rock art and wall paintings within caves. Methods: This study was conducted by collecting the samples scraped from wall surfaces at 19 different location in painted caves of Niah cave, Sarawak, and Tempurung cave, Perak. Morphospecies identification and genomic DNA polymorphisms were used to identify the two strains of bacteria. The growth was controlled chemical method using sodium hypochlorite (NaOCl), Calcium hypochlorite Ca(OCl)2 and hydrogen peroxide (H₂O₂). Results: Morphospecies identification was carried out using a light microscopy and scanning electron microscopy (SEM), both the bacteria, bacteria I and bacteria II were isolated from the soil samples and were Gram-negative bacteria. Based on BLAST search, bacteria I showed 100% with Stenotrophomonas sp (NR 024708.1), and bacteria II showed 100% with Cryptococcus liquefaciens (NR 043289. 1). The growth was controlled chemical method using sodium hypochlorite (NaOCl), Calcium hypochlorite Ca(OCl)2 and hydrogen peroxide (H₂O₂). The laboratory studies showed that three chemical were effectively eliminated colonies/cells of the both bacteria compared to the colonies found on the control pate this study.

scholarly journals A Fuzzy MADM Approach for Selecting the Best Cyanide Removal Method from a Gold Mine Wastewater

2021 ◽  
Author(s):  
Mohammad Hayati ◽  
Seyed Mohammad Seyed Alizadeh Ganji ◽  
Seyed Hadi Shahcheraghi
Keyword(s):  
Hydrogen Peroxide ◽  
Decision Making ◽  
Sodium Hypochlorite ◽  
Fuzzy Topsis ◽  
Gold Mine ◽  
Calcium Hypochlorite ◽  
Gold Mines ◽  
Removal Method ◽  
Fuzzy Delphi ◽  
Cyanide Removal

Abstract The cyanidation process is the most common method applied for the extraction of gold and silver in the hydrometallurgy industry, in which, sodium cyanide is used as a leaching agent. Therefore, the wastewater of gold mines contains a wide variety of cyanide ions needing to be removed before these wastewaters can be discharged to the receiving environments. In this study, a fuzzy multi-attribute decision-making approach (Fuzzy Delphi AHP and Fuzzy TOPSIS) was used for selecting the best cyanide removal method from the wastewater of Muteh gold mine. According to the experts' opinion, three methods including calcium hypochlorite, hydrogen peroxide and sodium hypochlorite were selected as alternatives. Then, by introducing the criteria influencing decision making, including cyanide removal ability, cost of process, amount of material consumed, time, pH, ease of performance and safety, and performing separated experiments, the criteria for each of three methods were determined. Finally, sodium hypochlorite was proposed as the best method for eliminating cyanide from wastewater. It was found that the rank of methods was as sodium hypochlorite (0.517) > calcium hypochlorite (0.474) > hydrogen peroxide (0.463).

scholarly journals Kennel Disinfectants forMicrosporum canisandTrichophytonsp.

2015 ◽  
Vol 2015 ◽  
pp. 1-3 ◽  
Author(s):  
Karen A. Moriello
Keyword(s):  
Hydrogen Peroxide ◽  
Sodium Hypochlorite ◽  
Contact Time ◽  
Growth Control ◽  
Calcium Hypochlorite ◽  
Good Efficacy ◽  
Antifungal Efficacy ◽  
Potassium Peroxymonosulfate

The antifungal efficacy of commonly used kennel disinfectants for large surfaces was tested using naturally infective material from untreated animals (M. canisandTrichophytonsp.) soaked and macerated but unfiltered leaving visible fluorescing hairs and/or scales in the test inoculum to create a robust challenge. Disinfectants included sodium hypochlorite (1 : 32 and 1 : 100), enilconazole (1 : 100), accelerated hydrogen peroxide (1 : 16), potassium peroxymonosulfate (1% and 2%), and calcium hypochlorite “dry bleach.” Disinfectants were tested at a 1 : 10, 1 : 5, and 1 : 1 dilution of test inoculum to disinfectant with a 10 min contact time. Good efficacy was defined as a disinfectant resulting in no growth. Control plates grew >300 colonies of each pathogen per plate. Enilconazole, sodium hypochlorite (all dilutions), accelerated hydrogen peroxide, and 2% potassium peroxymonosulfate (but not 1%) inhibited all growth of both pathogens at 1 : 10, 1 : 5, and 1 : 1 dilutions. Calcium hypochlorite showed no antifungal efficacy (>300 colonies per plate). Enilconazole (1 : 100), sodium hypochlorite (1 : 32 or 1 : 100), accelerated hydrogen peroxide (1 : 16), and 2% potassium peroxymonosulfate are recommended for decontamination of kennels exposed to dermatophyte pathogens.

scholarly journals Effect of Scouring and Bleaching Agents on whiteness Index and Bursting Strength of Cotton Knitted Fabric

2019 ◽  
pp. 23-28
Author(s):  
MD. Tofazzal Hossain ◽  
Alimran Hossain ◽  
Palash Kumar Saha ◽  
MD. Zahangir Alam
Keyword(s):  
Hydrogen Peroxide ◽  
Caustic Soda ◽  
Sodium Hypochlorite ◽  
Knitted Fabric ◽  
Bleaching Agent ◽  
Calcium Hypochlorite ◽  
Bleaching Process ◽  
Whiteness Index ◽  
Bursting Strength ◽  
Cotton Knitted Fabric

This paper shows the effect of different bleaching agent on whiteness index and bursting strength of the cotton knitted fabric. Bleaching process uses three types of bleaching agents namely hydrogen peroxide (H2O2), sodium hypochlorite (NaOCl) and calcium hypochlorite Ca(OCl)2 with varying their concentration and these are 1.5 g/l, 2.5 g/l, 3.5 g/l, 4.5 g/l, and 5.5 g/l. In the same time, scouring agent was caustic soda, and its concentration for all the bleaching agents was same. It is obvious that with the increase of bleaching agent concentration, whiteness index increases, and bursting strength reduces.

scholarly journals Studies on the Preservation of Raw Cow’s Milk by Chemical Method

1970 ◽  
Vol 42 (3) ◽  
pp. 317-326 ◽  
Author(s):  
F Rokhsana ◽  
UK Das ◽  
R Yeasmin ◽  
A Nahar ◽  
S Parveen
Keyword(s):  
Hydrogen Peroxide ◽  
Chemical Method ◽  
Room Temperature ◽  
Storage Period ◽  
Total Coliform ◽  
Human Consumption ◽  
Milk Products ◽  
E Coli ◽  
Keeping Quality ◽  
Control Milk

Studies carried out to develop a technique for the preservation of cow's milk in raw condition using hydrogen peroxide (H2O2) as a preservative. Fresh cow’s milk was collected and experiments were conducted by four treatments in order to achieve the optimum condition of storage. The treatments were with various concentration of H2O2 starting from 0.05 %, 0.1 %, 0.2 %, 0.3 %, 0.4 %, & 0.5 %. Treated milk with 0.05 % concentration of H2O2 had storage period of 20 days compared to that of the control one (5 days only) in refrigerated temperature (±8°C). On the other hand hydrogen peroxide treated milk (0.05 %) had a storage period of 8 hours at room temperature (±28°C). Results also showed that the higher concentration of H2O2 had no effect on storage period than that of control. Milk products like kheer and halawa prepared by treated milk and stored for 20 days showed almost nil growth of total coliform and E. coli which means that food products prepared from hydrogen peroxide treated milk is safe for human consumption. Key words: Raw, Storage, Hydrogen peroxide, Preservative, keeping quality, Pasteurization, deteriorated, MPN. Bangladesh J. Sci. Ind. Res. 42(3), 317-326, 2007

scholarly journals Impact of two disinfectants on detachment of Enterococcus faecalis from polythene in aquatic microcosm

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
C. Lontsi Djimeli ◽  
A. Tamsa Arfao ◽  
V Rossi ◽  
N Nsulem ◽  
V Raspal ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Adhesion ◽  
Enterococcus Faecalis ◽  
Sodium Hypochlorite ◽  
Growth Phases ◽  
Planktonic Cells ◽  
Stationary Growth ◽  
Experimental Conditions ◽  
The Impact ◽  
Aquatic Microcosm

<p><strong>After cell adhesion processes in microcosm, the impact of sodium hypochlorite (NaOCl) and hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) on the detachment of <em>Enterococcus faecalis </em>from polythene fragments immersed in water under stationary and dynamic conditions was assessed. The abundance of planktonic cells was also evaluated. The density of <em>E. faecalis</em> adhered in absence of disinfectant fluctuated between 2 and 4 units (Log CFU/cm<sup>2</sup>). </strong><strong>After living in disinfected water, </strong><strong>the density of <em>E. faecalis</em> remained adhered to polythene sometimes reached 2 units (Log CFU/Cm<sup>2</sup>)</strong><strong>. </strong><strong>This highest abundance of cells remained adhered was recorded with cells coming from the lag, exponential and stationary growth phases in water treated with 0.5‰ NaOCl. In H<sub>2</sub>O<sub>2</sub> disinfected water, the highest value was recorded at all cells growth phases with 5‰ H<sub>2</sub>O<sub>2 </sub>concentration. Adhered <em>E. faecalis</em> cells have been sometimes completely or partially decimated respectively by NaOCl and H<sub>2</sub>O<sub>2</sub> treated water. Considering separately each experimental condition, it was noted that increasing the concentration of disinfectant caused a significant decrease (P≤0.01) in abundance of cells stay adhered after living in water disinfected by the two disinfectants. Changes in disinfectant concentrations in different experimental conditions had an impact on the detachment of <em>E. faecalis</em> cells from the substrates. </strong></p>

scholarly journals Bleaching of Microcrystalline Cellulose Produced by Gas-Phase Hydrolysis

2021 ◽  
pp. 173-183
Author(s):  
Alexander I. Sizov ◽  
◽  
Sergey D. Pimenov ◽  
Anastasia D. Stroiteleva ◽  
Katherine D. Stroiteleva ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Pharmaceutical Industry ◽  
Gas Phase ◽  
Sodium Hypochlorite ◽  
Microcrystalline Cellulose ◽  
High Rate ◽  
Subsequent Formation ◽  
Hydrolysis Of Cellulose ◽  
Yellow Tint ◽  
Hydrolysis Of

One of the main consumers of microcrystalline cellulose (MCC) is the pharmaceutical industry, where MCC is used as a binder and filler in direct compression of tablets. MCC is produced by acidic hydrolysis of cellulose, which usually results in a decrease in whiteness. This is due to the destruction of sugars formed during hydrolysis and the subsequent formation of colored products. The composition and properties of these products depend on the method of hydrolysis, acid concentration, temperature, and process duration. One of the most promising methods for producing MCC is gas-phase hydrolysis of cellulose with hydrogen chloride gas-air mixtures. The method has a high rate of hydrolysis, low reagent and energy consumption. The requirements of the pharmaceutical industry determine the need to produce MCC with high whiteness. The research purpose is to select bleaching modes for MCC using sodium hypochlorite and hydrogen peroxide as bleaching agents. MCC produced by gas-phase hydrolysis of bleached wood pulp was used during the study. The whiteness and intensity of the yellow tint of MCC in the bleaching process were determined by digital colorimetry on a flatbed scanner. The paper shows that sodium hypochlorite and hydrogen peroxide allow achieving the whiteness not less than 90 % and the intensity of the yellow tint not more than 3 standard units. High-quality bleaching can be carried out even for MCC samples with an initial whiteness of about 40 %. The most effective bleaching agent is sodium hypochlorite when the pH of the bleaching solution is 2–3. Hydrogen peroxide also provides high whiteness of MCC at pH of 10–11. However, the consumption of active oxygen (AO) for bleaching is more than three times higher in comparison with the consumption of active chlorine (ACh). It was found that the dyes of MCC produced by gas-phase hydrolysis consist of two chromophore groups that decolorize at different rates. The easily oxidized group of components makes up about 90 % of the total amount of dyes, and the resistant to oxidation components make up about 10 % and determine the intensity of the yellow tint of MCC. The modes of bleaching MCC with sodium hypochlorite and hydrogen peroxide to product samples with whiteness comparable to that of imported samples were determined. For citation: Sizov A.I., Pimenov S.D., Stroiteleva A.D., Stroiteleva K.D. Bleaching of Microcrystalline Cellulose Produced by Gas-Phase Hydrolysis. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 173–183. DOI: 10.37482/0536-1036-2021-6-173-183

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