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The article presents a study of the coefficients of heat transfer of the built-in heat exchanger (deflegmator) of the distillation column used in technological lines of chemical processing of wood biomass. Mathematical modeling was carried out on the effect of changes in one of the technological parameters (diameter of the heat exchanger tubes, material of the heat exchanger and coolant) of the heat exchanger on the heat transfer coefficient. Rectification is widely used in the following industries: in the technologies of complex wood processing; in the forestry industry in the production of consumer products; in the recovery of extraction solutions in the extraction of biologically active substances from plant raw materials; in the technology of chemical processing of wood in the production of ethanol; when processing increasing natural waste by gasification and using synthesis gas to produce a biopolymer at the stage of solvent regeneration (methylene chloride, sodium hypochlorite, hexane, etc.), where highly efficient and productive distillation columns are also in demand. For the most part, multicomponent mixtures are subject to rectification, as a rule, azeotropic, having a similar boiling point, which explains the use of multi-stage rectification columns for their separation. At the same time, various methods of rectification are used, such as azeotropic, extractive, molecular, fractional, partial. [ABSTRACT FROM AUTHOR]

Sodium hypochlorite (NaOCl) is an efficient root canal irrigation material for eradicating pathogens and dissolving necrotic tissue. Significant influences on the efficacy of the irrigation material were concentration, time, and temperature. Increasing the temperature of a NaOCl solution with a minimum concentration is an alternate method for reducing toxicity and enhancing NaOCl's effectiveness. The aim of this research is to determine the antimicrobial effect of increasing the temperature of 2.5% NaOCl as a root canal irrigation material on Enterococcus faecalis bacteria and the antimicrobial effect of temperature degrees in 2.5% NaOCl. As the P value exceeds 0.05, the Shapiro-Wilk test indicates that the results of this study have an irregular distribution. In addition, since the Kruskall-Wall is test yielded a P value of 0.05, it can be inferred that the data sets do not differ significantly. The Mann-Whitney Post-Hoc test, where the P value is less than 0.05 and indicates that there is no statistically significant difference between the tested data, supports this. The antimicrobial effect of a 2.5% NaOCl solution at 60 °C, 65 °C, or 70 °C has no discernible impact on E. faecalis. Pathogenic factors and the use of NaOCl cause this. At 60 °C, 65 °C, and 70 °C, it is anticipated that decreasing the concentration of Sodium Hypochlorite from 5.25 to 2.5% will diminish the toxicity and maintain the antibacterial effect against E. faecalis bacteria. [ABSTRACT FROM AUTHOR]

A diesel particulate filter (DPF) can remove the diesel particulate matter from the incomplete combustion exhaust gases of diesel engine vehicles. The regeneration process of DPF is critical since the cost of the DPF/catalytic system for Euro 5/6 Diesel Cars has been calculated as half of the cost of the whole engine of the car. Nowadays, organic based solvents are used for regenerating filters while simultaneously revealing potential toxicity. As a result, there is a need for an innovative and environmentally friendly regenerating process. The studied reagents were citric acid, a deep eutectic solvent (DES) of choline chloride and lactic acid, sodium dodecyl-benzene sulfonate, and sodium hypochlorite. By this novel regenerating method, up to 90% of the organic compounds from diesel filters were removed. [ABSTRACT FROM AUTHOR]

During the global health crisis that caused by the Corona pandemic, the development of detergent products has become necessary to confront the spreading of viruses, bacteria, and fungi. Here, three types (X, Y, and Z) of new triple-action glass cleaners (cleaning, polishing, and sterilizing) were prepared from locally available, low cost, and alcohol-free chemicals. The new glass cleaners were prepared by mixing the preservative, color, and perfume with Cocamidopropyl betaine as a surfactant and 5%, 3%, and 1% of Chloroxylenol, Povidone, and Sodium hypochlorite solutions were added as sterilizers respectively. The second part also included the study of some physicochemical properties and antimicrobial activity of the products such as boiling point, pH, viscosity, water solubility, stability and anti-bacterial. In the end, the prepared products were compared with two commercial products (A & B). It was found that the new products possess high cleaning, polishing, and sterilization properties. [ABSTRACT FROM AUTHOR]

Production of sources of biologically active substances of plant origin is an urgent problem due to their wide application in medicine, food industry, veterinary medicine, in agriculture as growth agents. The aim of this work is to investigate the features of in vitro culture of the plant Circaea lutetiana L. This kind of plant has been widely and long used in folk medicine of many peoples. The research revealed that for sterilizing the seeds of Circaea lutetiana L. when entering them into an in vitro culture it is advisable to use Sodium hypochlorite 10 % or Avansept 6% solution at an exposure time of 20 minutes. In order to develop methods of artificial cultivation of medicinal plants, it will be possible to use valuable composition of plants to a greater extent, while preventing the impoverishment of species and population diversity of the flora. [ABSTRACT FROM AUTHOR]

Birds have evolved specialized nests, varying across habitats and available resources. But those habitats and resources are now changing, as multiple anthropogenic factors, including plastic pollution, threaten birds. The intensity and prevalence of plastic pollution in bird nests remains unknown. I intend to better understand the impact of human activity on birds by studying the presence and quantity of synthetic material within nests. I hypothesize that birds near human-impacted areas use more synthetic material within their nests. Therefore, I predict that there will be negative correlations between plastic content and their distance to human-impacted areas. I used Carolina Chickadee (Poecile carolinensis) nests, collected over three years (2021 - 2023), from standardized bird boxes in varying habitats at Warren Wilson College in western North Carolina, USA. After recording initial nest measurements, I isolated microplastics through water-bathing and filtering. I then assessed microplastic presence through fluorescence detection under a microscope. Next, I dissolved the natural nesting material of the nest linings with 7% sodium hypochlorite solution for 9 weeks, thereby leaving me with just the macroplastics. I confirmed that these were plastic by using fluorescence detection. I then compared the mass of this isolated synthetic material to the initial nest mass to determine the proportion of each nest that was made-up of macroplastics. I will use a linear regression to compare the amount of macroplastic to the distance between nests and their closest human-impacted area. For this study, I am considering roads, rivers, and buildings as high human-impacted areas because they are major sources of plastic pollution. For microplastic analysis, I will test how the probability of microplastic presence relates to proximity to human-impacted areas. I predict that both the quantity of macroplastics and the presence of microplastics will be higher in nests that are closer to sources of plastic pollution. [ABSTRACT FROM AUTHOR]

The aim of this study was to the isolate the endophytic bacteria, optimize its isolation procedure. Ethanol, sodium hypochlorite, and mercuric chloride at various concentrations and duration were employed to optimize the surface sterilization for the isolation of endophytes from Phaseolus vulgaris, Pisum sativum, and Hordeum vulgare. A total of 21 endophytic bacteria have been isolated from three plants. Combination of 2% sodium hypochlorite, 70% ethanol, and 0.1% mercuric chloride was found effective for the surface sterilization of Phaseolus vulgaris and Pisum sativum. In case of Hordeum vulgare, 70% ethanol and 2% sodium hypochlorite was found suitable for the surface sterilization. Ethanol, sodium hypochlorite, and mercuric chloride were found effective decontaminating agents in optimum condition. [ABSTRACT FROM AUTHOR]

The majority of capsule shells until 2014 are still made from gelatin from pork skin and bones. To overcome this problem, research on vegetable capsule shells began to develop based on seaweed extracts such as carrageenan, alginate, HPMC, and pectin. Existing vegetable capsule shells need to be upgraded to be more robust with the addition of polyhydroxybutyrate (PHB). Spirulina platensis microalgae is a PHB producer that is easy to cultivate, its production can be optimized by modifying the isolation method. Chemical disruption is the most simple and economical cell disruption method. It is followed with isolation steps of PHB precipitation and PHB purification. Sodium hypochlorite (NaClO) is a cell-disrupting solvent that is widely used for isolation of PHB from microalgae while sodium hydroxide (NaOH) has been used to isolate PHB from bacteria. The independent parameter tested in this study is the ratio of NaClO and NaOH used for cell disruption solvent ranging from 100:0, 85:15, and 75:25. The PHB quantification method used was FTIR, while for characterization is by calculating the PHB mass and extraction yield. The expected results of this PHB extraction is to get maximum yield of PHB and the most efficient extraction method based on the cell disruption solvent composition. Extraction of microalgae sample with 100:0 ratio of NaClO:NaOH is expected to have the highest yield of PHB compared to other variations. [ABSTRACT FROM AUTHOR]

The situation caused by Covid-19 pandemic has caused impact on environment, due to the limited human activities, and actions against Covid-19 spread. In this paper there will be presented the results of the experimental investigation of using sodium hypochlorite for disinfection purposes to the river Ibar water quality and aquatic organisms. The city streets and buildings were disinfected on daily basis, and the waste waters were collected into storm water pipelines, directed to the sewerage and discharged into the river. There is no waste water treatment facility involved, and the domestic sewage was mixed with storm water flow, entering the river at the same discharge point. For better understanding of this impact, the results from the physical, chemical and micro biological testing of the river water quality were compared to the pre-Covid time. The results have shown that the river is III class of water, and the values for Nitrate, Nitrite and BOD were exceeding the values for the III class. The concentration 0.1% of NaOCl is sufficient to eliminate Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa during the exposure time of 5 min. Since these microorganisms, which are often found in surface waters and are sensitive on low concentrations of disinfectants, were not isolated in the sample analysis, this can be contributed to sodium hypochlorite. As the river Ibar is natural recipient of all wastewater from the north part of this region, it is necessary to continuously monitor water quality and implement protection measures, in anticipation of the wastewater treatment plant construction. [ABSTRACT FROM AUTHOR]

It is predicted in 2019, 91.1% of capsule shells produced are made from gelatin which is not suitable for vegetarians and some religious groups. Research on vegetable capsule shells began to develop to substitute gelatin using seaweed extracts such as carrageenan, alginate, HPMC, and polyhydroxybutyrate. Spirulina platensis microalgae is a PHB producer that is easy to cultivate, and its production can be optimised by modifying the extraction method. Solvent extraction is the most simple and economical extraction method with general stages in the form of cell disruption, PHB precipitation, and PHB purification. Sodium hypochlorite (NaClO) is a cell-disrupting solvent that is widely used for the extraction of PHB from microalgae. The parameters tested in this study consist of concentration of S. platensis sample cells shown as optical density (OD) ranging from 1, 2, 3, 4, 5, and 6. The PHB quantification and characterization method used was FTIR, and it showed the similarity between extracted PHB from Spirulina platensis with commercial PHB. The expected results of this PHB extraction are to get the maximum yield of PHB and the most efficient extraction method based on the independent variables. Extraction of microalgae sample with OD 4 using 4% NaClO is expected to have the highest yield of PHB. [ABSTRACT FROM AUTHOR]

The biological activity of hypochlorite is associated with aggressive oxidative interactions with a variety of functional groups leading to oxidative stress in biological systems. Gallium(III) is a well known anticancer agent. Its complex (GaAOA) with 5-aminoorotic acid (HAOA) exhibits antioxidant activity. The aim of the current study is to establish the impact of HAOA and GaAOA on the luminol-dependent chemiluminescence (LDCL) in presence of sodium hypochlorite (NaOCl). A concentration dependent decrease of LDCL is observed in the presence of both investigated substances. At equimolar concentrations, GaAOA demonstrates more potent antioxidant activity. Spectral data indicates that an interaction between hypochlorite and the amino-group of the ligand takes place, contributing to the antioxidant effect of HAOA and its Ga(III) complex. [ABSTRACT FROM AUTHOR]

Modern viticulture of Russia should be based on the production of certified planting stock. The production of planting material of the highest categories in the Russian Federation is absent. The main goal of the research was to improve the technology of clonal micropropagation using growth regulators. The task was to obtain a healthy planting stock of grapes and to introduce a certification system for planting material according to the pattern of European countries. The object of research were complexresistant varieties of grapes. As an initial material, intensively growing green shoots of grapes were taken, which were cut into single-eyed cuttings and further carried out the isolation of meristems in laminar boxes. The following varieties were included in the experiment: Augustin, Moldova, Delight, Muscat Italian, Early Magaracha, Gift of Magarach, Viorika, etc. One-slice cuttings before sterilization of the meristem were sterilized in a 2% solution of sodium hypochlorite. The sterilized organs were placed in a sterile Petri dish. Isolated meristems from 200 to 400 microns with a special preparation needle and immediately placed on the surface of the agar medium in Petri dishes. Cultivation of plant material was carried out in the first stage in Petri dishes, then in 40 x 120 mm test tubes containing 20 ml of nutrient medium. It was developed the method of obtaining virus-free plants is based on the fact that the content of viruses in the diseased plant decreases towards the shoot tip. The apical meristem is usually free from viruses. The conducted observations showed during the first stage of cultivation (2 weeks) a part of meristems was necrotic. The remaining meristems a month later after landing have evolved into micropiles of 2 - 2.5 mm. These micro-races were re-transplanted into the same nutrient medium. The transplant was made into biological test tubes. The degree of survival of apical meristems at the stage of introduction into culture in vitro in the group of table varieties (Augustin, Delight, Muscat Italian, Early Magarach) is on the average at 50%, and in technical varieties (Gift of Magarach, Viorica, Rkatsiteli) - 40-45 %. The surviving apical meristems, a month after planting, were transplanted into a nutrient medium containing the same components. The transplantation was carried out in biological test tubes measuring 40 x 120 mm, during 45-55 days, regenerants with a size of 6- 10 cm were formed. Then these microplants were stripped and microclones were obtained. Thus, it should be noted that 40% of the survival rate of the apical meristems allows their further cultivation and propagation, in which the production of virus-free planting material. [ABSTRACT FROM AUTHOR]

The chemical interactions between PE and bleach were studied at 60°C in immersion in bleach solutions kept at a free chlorine concentration of 100 ppm and a pH of 5 or 7.2. It was found that the polymer undergoes a severe oxidation from the earliest weeks of exposure, in a superficial layer whose thickness (of about 50-70 μm) is almost independent of the pH value, although the superficial oxidation rate is faster in acidic than in neutral medium. Oxidation leads to the formation and accumulation of a large variety of carbonyl products (mostly ketones and carboxylic acids) and, after a few weeks, to a decrease in the average molar mass due to the large predominance of chain scissions over crosslinking. A scenario was elaborated for explaining such unexpected results. According to this scenario, the non-ionic molecules (Cl2 and ClOH) formed from the disinfectant in the water phase, would migrate deeply into PE and dissociate into highly reactive radicals (Cl• and HO•) in order to initiate a radical chain oxidation. A kinetic model was derived from this scenario for predicting the general trends of the oxidation kinetics and its dependence on environmental factors such as temperature, free chlorine concentration and pH. The validity of this model was successfully checked by comparing the numerical simulations with experimental data. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study on the chemical oxygen demand (COD) values of the effluent from the peracetic acid bleaching process and the comparison with those from the conventional bleaching processes based on sodium hypochlorite or hydrogen peroxide. The objectives of the study are discussed, including evaluating the effectiveness of yeasts in the desizing process and the bleaching effect of cotton after peracetic acid bleaching. The study concluded that yeast can enhance the desizing effect and improve the COD value of the effluent provided that optimum conditions are used.

The article focuses on hydrogen peroxide bleaching of cotton hosiery. It notes that sodium hypochlorite has been used to bleach cotton hosiery yet a shift in trend has led to the consideration of hydrogen peroxide for the bleaching process. Several changes in the hosiery business attributed to the shift in trend are discussed which are enhancement of product quality, introduction of continuous bleach processes and equipment and environmental concerns. It presents the results of a study on hydrogen peroxide bleaching which asserts that hydrogen peroxide concentration drives the bleaching process.

Bleaching tests were conducted to study the efficacy of peracetic acid (PAA) as a replacement for sodium hypochlorite in multistage bleaching processes of cotton and linen. The study showed that peracetic acid is most effective as a bleaching agent in the pH range of 6 to 7. The preferable bleaching temperature range is between 50-80°C (120-175°F). The required dwell time for a peracetic acid bleaching stage is comparable to the NaOCl bleaching. Typically, bleaching time is between 20-60 minutes depending on the applied temperature. As in all bleaching processes, the degree of brightness increases proportionally with the bleaching agent concentration. Bleaching of 100% cotton goods in rope form in a J- box with peracetic acid (1.5-2.5 g/l) at room temperature, followed by an alkaline H2O2 treatment at 90°C yielded a brightness of over 90 (Berger). Linen yarns could be successfully bleached using a process consisting of scouring, alkaline H2O2 bleach and a PAA bleaching stage. Starting with a raw material with a brightness of 20, a final brightness number of 78 was obtained after the PAA bleaching stage. In all bleaching tests, the PAA process was found to be less fiber damaging than NaOCl. [ABSTRACT FROM AUTHOR]

The synthesis of polyaniline has been reported using three different oxidative reagents: ammonium persulfate, potassium iodate and potassium iodate+sodium hypochlorite. This polyaniline has been used to prepare several nanocomposites with different percentage of Montmorillonite. The DC conductivity of the nanocomposites was determined by impedance spectroscopy. The oxidative reagent that gives higher conductivity is ammonium persulfate. The temperature dependence of the conductivity was studied. [ABSTRACT FROM AUTHOR]

The hypochlorite ion (OCl-), a major product of the radiolysis of water in solutions containing high concentrations of chloride, can be expected to influence the oxidation state distribution of plutonium in these solutions. Since plutonium has significantly different chemistry in each of its oxidation states, knowledge of the oxidation state distribution of plutonium and of the kinetics of transfer between these oxidation states is essential for modeling the behavior of plutonium in aqueous systems and for design of efficient remediation procedures for plutonium containing wastes. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]