Organic Substances
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2022 ◽  
Vol 45 ◽  
pp. 102510
Author(s):  
Hiyam Khalil ◽  
Hanaa M. Hegab ◽  
Lobna Nassar ◽  
Vijay S. Wadi ◽  
Vincenzo Naddeo ◽  
...  

2022 ◽  
Vol 8 (1) ◽  
pp. 93-100
Author(s):  
Z. Aliyev ◽  
M. Ziyadov ◽  
E. Mamedova

The cultivation of perennial grasses in mountainous areas protects the slopes from erosion and provides animals with good food. According to the results of the studies, it was determined that the restoration of fertility and the ecological balance of erosional lands and the implementation of soil and agrotechnical measures is of great importance for increasing yields. Thanks to the application of these measures, as a result of the improvement of the water-physical properties of the affected lands, runoff of surface waters is prevented. Perennial grasses accumulate the nitrogen atmosphere of legumes, enrich the soil with organic substances, accelerate the formation of a water-resistant granular-fuel structure and improve its water-physical properties, which in turn contributes to the rapid assimilation of minerals.


2021 ◽  
Vol 18 (4) ◽  
pp. 143-152
Author(s):  
D. O. Tsymbal ◽  
M. E. Mazanik

Objective. To evaluate the effectiveness of photocatalytic methods of oxidation of organic substances for the preparation of drinking water. To show the expediency of the use of the described method for the design of wastewater treatment facilities.Materials and methods. The oxidation degrees of 58 organic substances of various hazard classes were studied. The sampling frame was based on two characteristics: origin (biological and artificial) and the oxidation state stated in different sources.Results. A high efficiency of photocatalysis for the destruction of organic substances in wastewater from various industries has been shown: the degrees of oxidation range from 70 to 100 %.Conclusion. Photocatalysis can be used to design wastewater treatment facilities with a view to reducing the probability of biological pollution of natural waters intended for drinking water production.


Membranes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 39
Author(s):  
Magdalena Lech ◽  
Agnieszka Klimek ◽  
Damian Porzybót ◽  
Anna Trusek

As biodiesel production as renewable fuel increases, so does the amount of wastewater resulting from this technology. Wastewater is generated during the so-called biodiesel washing, i.e., washing out glycerol and methanol with water. The purified biodiesel must meet international standards, such as EN 14214 or the American ASTM D6751 standard. To fully say that biodiesel technology is environmentally friendly, the amount of wastewater should be minimized. It is also desirable that the purified water can be recycled to the technology. For this purpose, wastewater pre-treated by flotation, during which mainly oils are removed, was subjected to three-stage membrane separation. For each of the stages, the membrane was selected and characterized in terms of its separation capacity and stream stability. Starting with microfiltration, which was mainly aimed at reducing turbidity, affects the permeate flux in the following steps. Then, ultrafiltration and nanofiltration membranes were selected. These membranes were aimed at reducing the concentration of inorganic and organic substances. Consequently the cascade was composed of: MF-0.45 µm, UF-150 kDa, and NF-characterized by an 80% degree of desalination. The final permeate has a salt concentration of less than 0.15 g/L and can be reused in biodiesel technology.


Author(s):  
P. H. Kopytko ◽  
◽  
R. V. Yakovenko ◽  
I. P. Petryshyna

The balance of humus in a meter layer of dark gray, podzolized soil and podzolized chernozem of the experimental apple orchads and the study of their long-term fertilization was investigated (from the planting to 50-year old trees) with the use of organic (40 t/ha of cattle manure) and mineral fertilizers (N120P120K120), which were applied once in two years in autumn under the plowing in the row spacings at a depth of 18 20 cm. In the 20-year period (from 30- to 50-year-old experimental gardens) in a meter layer of dark gray podzolized soil on the non-fertilized control plots the amount of humus increased by 27 t/ha, and on the plots fertilized with manure – by 7 t/ha more and on the plots with mineral fertilizers – by 6 t/ha less and in podzolized chernozem – 37 t/ha and 3 t/ha more and 10 t/ha less respectively. Such changes in humus storage were caused by different replenishment of organic substances, and, to a greater extent, an increase in the biological activity of the fertilized soil, in particular the intensity of mineralization processes of organic matter, and in particular the humus compounds. Also, the replanishment of such soils in the gardens by the organic mass of fallen leaves and thin (d≤1mm) small roots, which systematically grows and dies, providing root nutrition of fruit plants, was investigated. These sources supplemented with organic substances the layer of soil of 0 20 cm – with all the mass of leaves and 38,5 43,3% of the total roots, and the increase in humus content was in all roots of the layer of 0 60 cm: in non-fertilized areas of 11 t/ha in dark gray soil and 18 tons per hectare in chernozem, under organic fertilizers, by 14 and 19 t/ha, and under mineral fertilizers – by 3 and 9 t/ha respectively. The greatest quantity of humus was added in the layer 60 100 cm: 16 and 19 t/ha, 20 and 21 t/ha and 18 t/ha. Such results were conditioned by the intensification of biological activity, in particular mineralization processes, in the upper layers of fertilized soils at higher humus content, as well as the migration of soluble humus substances deep into the meter profile.


Author(s):  
Oleksandr Dzevochko ◽  
Mykhaylo Podustov ◽  
Alona Dzevochko ◽  
Vladimir Panasenko

The processes that occur in film absorbers during the sulfation of two-component mixtures of organic substances are quite complex and require mathematical modeling. This paper reports the construction of a mathematical model that makes it possible to adequately describe the process of sulfation involving gaseous sulfur trioxide in the production of surfactants. Based on the model, it became possible to investigate this process for higher alcohols of fractions С12–С14 and monoethanolamides of higher fatty acids of coconut oil. The data are given on the comparison of mathematical modeling results based on the mathematical model built with known experimental data and results of alternative mathematical modeling for different ratios of the length of the reaction pipe to its diameter (l/d). It is shown that the error in comparing the experimental data was 4.8–9.6 % at l l/d=29; 1.1–8.7 % at l/d=70; 3.9–12.3 % at l/d=144. The error in comparing known results of alternative mathematical modeling was, respectively, 6.3–7.2 %, 0.1–6.5 %, 0–1.0 %. These results were obtained for the molar ratio in the range of 1.0–1.15 and the SO3 concentration in the stream of 4.0–6.0 %. Such findings suggest that the established dependences of the basic parameters for the sulfation process are adequate in terms of the absorber length and its radial direction. Therefore, the mathematical model built does hold within the considered ranges of input variables. Consequently, it could be used in the theoretical study of the process of sulfation of two-component mixtures of organic substances by gaseous sulfur trioxide in a film absorber with a downward flow of phases. The results obtained could be used in practice, in particular in the manufacture of high-quality products for the cosmetic industry.


Author(s):  
A. S. Panasyugin ◽  
N. D. Pavlovskiy ◽  
N. P. Masherova ◽  
A. R. Tsyganov ◽  
I. I. Kurilo

The purpose of this work is to study the process of neutralization of vapors of a mixed solvent of the brand 650 by the adsorption‑catalytic method. The essence of the method consists in the concentration of solvent components on the sorbent, thermal desorption followed by periodic flameless catalytic oxidation of accumulated organic substances to carbon dioxide and water. Synthetic zeolite of the NaX brand was used as a sorbent, and a porous material based on foam ceramics of the Al2O3/SiO2 composition with a highly developed modified surface with an active catalytic phase was used as a catalyst. The mixed solvent contains, xylenes, ethylcellosol, n‑butanol. It is shown that the value of the sorption volume of zeolite for each class of the considered compounds is influenced by certain factors: the length and structure of the carbon skeleton, the position of the hydroxyl group (for alcohols and esters), the number of methyl groups in the composition of molecules (for the production of benzene). The conversion rate of the mixed solvent components was 65.4–90.1 %.


Lontara ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 82-88
Author(s):  
Rahmawati Rahmawati ◽  
Dewi Arisanti ◽  
Nurhidayat Nurhidayat

Gallons of refilled drinking water usually don't run out in a single use but run out in a few days or even up to 1 to 2 weeks, depending on usage, and stored at room temperature (27-29 °C). Drinking water that is stored for a long time will allow the growth of microorganisms which are influenced by environmental factors, namely temperature conditions and oxygen supply during storage. This affects the pH and total organic content of drinking water. Inspection of the quality of water products according to the Regulation of the Minister of Health of the Republic of Indonesia Number 492/MENKES/PER/IV/2010, which is a maximum organic matter content of 10 mg/L. According to chemical parameters, drinking water must not contain inorganic and organic substances exceeding the standard with a pH value between 6.5-8.5. The purpose of this study was to determine the levels of organic substances in RO (Reverse Osmosis) refill drinking water. This type of research is a laboratory experiment using purposive sampling technique. The results showed that the average organic content of refilled drinking water with a storage period of 0 days was 1.839 mg/L, 3 days was 2.57 mg/L, and 6 days was 5.28 mg/L. Thus, the levels of organic substances in drinking water are based on storage time of 0, 3, and 6 days using the spectrophotometric method according to the maximum drinking water quality standard.


2021 ◽  
Vol 48 ◽  
pp. 109-116
Author(s):  
Liudmila Stelmakh ◽  
Nela Kovrigina ◽  
Tatiana Gorbunova

For the degrees of toxicity assessment within the Black Sea surface coastal waters near Sevastopol, laboratory experiments were performed on three marine microalgae species culture’s growth in water sampled on the three stations of the region from May to December 2020. The study has indicated, that in the majority of cases, insignificant inhibiting influences of the waters to diatom Phaeodactylum tricornutum Bohlin and insignificant stimulated effect to dinoflagellates Prorocentrum сordatum (Ostenfeld) J.D.Dodge and Gyrodinium fissum (Levander) Kofoid & Swezy were observed. Rarely this effect was characterized as chronic or subacute. The concentration levels of both stable and unstable forms of organic substances in the studied waters were estimated. The results of the testing of the water to determine its contamination using microalgae and analysis of the organic substances concentration levels in them, allowed the conclusion that the studied area should be classified as episodically polluted. Justification for the necessity to use several microalgae species of different taxonomic affiliation when performing marine water biotesting is provided in this study.


2021 ◽  
Vol 937 (2) ◽  
pp. 022060
Author(s):  
Denis Butko ◽  
Yana Lazareva ◽  
Marina Sharkova

Abstract The paper presents a study of quality of natural waters and water in a centralized water supply system during the period of an increase in the “Smell” indicator in the spring of 2021. The chemical and physical properties of water, the results of quality and quantity of studying the variety I phytoplankton in the most difficult period of deterioration in quality of river water. Low water and exceeding MPC concentrations of organic substances in river water. The Don River causes altered form odorant substance as evidenced by the results of determination in water 1,2,3- t rihlorbenzol and geosmin, hexachloroethane and aniline shown in operation. Barrier function of reagent treatment methods used at water treatment plants in the lower reaches of the river. The Don River, even when combined with carbonated water, is deficient in odor-producing substances.


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