preliminary extraction
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2022 ◽  
Vol 12 (2) ◽  
pp. 569
Author(s):  
Yuliya Kulikova ◽  
Stanislav Sukhikh ◽  
Svetlana Ivanova ◽  
Olga Babich ◽  
Natalia Sliusar

At the moment, macroalgae blooms in sea waters, the rotting of which causes greenhouse gas emissions and contributes to the formation of a negative ecological and economic situation in coastal zones, which has become a serious problem. Fuel production through hydrothermal liquefaction (HTL) of macroalgae and marine debris is a promising solution to this ecological problem. The article provides an overview of studies on producing fuel from macroalgae and an assessment of the possibility of their joint recovery with marine debris. The optimal process conditions and their technological efficiency were evaluated. The article shows the feasibility of using heterogeneous catalysis and co-solvent to increase the yield of bio-oil and improve its quality. An assessment of the possibility of joint processing of waste macroalgae and marine debris showed the inexpediency of this direction. The high degree of drift macroalgae contamination also raises the question of the appropriateness of the preliminary extraction of other valuable components for nutrition use, such as fats, proteins, carbohydrates, and their derivatives.


Author(s):  
D. V. Charnyy ◽  
Ye. M. Matseluk ◽  
V. D. Levytska ◽  
S. V. Marysyk ◽  
N. M. Chernova

The current state and formation of water quality in reservoirs that serve as sources of drinking water supply were considered. It was revealed that phytoplankton becomes one of the main factors influencing the formation of water quality in reservoirs in the warm period from June to November, especially during the period of reservoirs “blooming”. Mostly these processes are triggered by the explosive development of blue-green algae (cyanobacteria). The factors accompanying this phenomenon are shown. The characteristic of the influence of global climate change and new composition of wastewater on water quality in surface water supply sources is given. If earlier the sewage contained significant volumes of heavy metals, oil products, phenols, etc., now they are observed to decrease at several times and vice versa - an increase in the volume of biogenic compounds, especially phosphates is observed. The emergence of phosphates is caused both by the ingress of phosphate fertilizers into water bodies, and by household reasons - the massive distribution of phosphate-based detergents and the inability of existing sewage treatment plants to efficiently process them. Screening monitoring of the Dnieper river basin showed extremely high levels of the predicted safe concentration of herbicides, insecticides, fungicides, as well as pharmaceutical substances such as carbomazepine, lopinavir, diclofenac, efavirenz, etc. in water. That is, among organic pollutants, the focus changes from classic petrochemical products to the products related to agricultural and pharmaceutical production, which, in certain concentrations, can stimulate the development of phytoplankton. The effective methods for treating surface water in modern conditions are as follows: - physical retention of coarse fractions of phytoplankton using new designs of water intake structures; - the use of new filter materials that effectively trap finely dispersed phytoplankton fractions at the main treatment facilities and are capable of regenerating the filter media; - the use of new oxidizing agents-disinfectants that do not form toxic organochlorine compounds, with preliminary extraction of phytoplankton masses;


2021 ◽  
Vol 947 (1) ◽  
pp. 012003
Author(s):  
H Q V Le ◽  
T D Tong ◽  
X C Luu ◽  
X T Le

Abstract The water extraction procedure (WE) was critically selected to extract (+)-catechin and (-)-epicatechin in cashew testa. The effects of different extracting factors, including multiple extraction, extracting temperature, extracting duration, and solvent-material ratio, on catechin amounts were evaluated. Under optimal conditions, a gram of water extract (WE’) contained 151.2±4.7 mg of (+)-catechin and 85.2±2.3 mg of (-)-epicatechin. These values were nearly three-folded compared to raw material, 55.0±1.4 and 31.0±0.6 mg, respectively. By using fractional extraction with ethyl acetate, the amounts of (+)-catechin and (-)-epicatechin per gram of ethyl acetate extract (WE2) in the present extracts respectively increased to 219.4±16.5 and 123.6±8.9 mg.


Diagnostics ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1325
Author(s):  
Lyudmila V. Bel’skaya ◽  
Elena A. Sarf ◽  
Victor K. Kosenok

We have developed a method for studying the lipid profile of saliva, combining preliminary extraction and IR spectroscopic detection. The case–control study involved patients with a histologically verified diagnosis of breast and prostate cancer and healthy volunteers. The comparison group included patients with non-malignant pathologies of the breast (fibroadenomas) and prostate gland (prostatic intraepithelial neoplasia). Saliva was used as a material for biochemical studies. It has been shown that the lipid profile of saliva depends on gender, and for males it also depends on the age group. In cancer pathologies, the lipid profile changes significantly and also depends on gender and age characteristics. The ratio of 1458/1396 cm−1 for both breast and prostate cancer has a potential diagnostic value. In both cases, this ratio decreases compared to healthy controls. For prostate cancer, the ratio of 2923/2957 cm−1 is also potentially informative, which grows against the background of prostate pathologies. It is noted that, in all cases, changes in the proposed ratios are more pronounced in the early stages of diseases, which increases the relevance of their study in biomedical applications.


Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4102
Author(s):  
Cristhian Carrasco ◽  
Leif J. Jönsson ◽  
Carlos Martín

Auto-catalyzed hydrothermal pretreatment (A-HTP) and sulfuric-acid-catalyzed hydrothermal pretreatment (SA-HTP) were applied to quinoa stalks in order to reduce their recalcitrance towards enzymatic saccharification. Prior to pretreatment, quinoa stalks were extracted with either water or a 50:50 (v/v) ethanol–water mixture for removing saponins. Extraction with water or aqueous ethanol, respectively, led to removal of 52 and 75% (w/w) of the saponins contained in the raw material. Preliminary extraction of quinoa stalks allowed for a lower overall severity during pretreatment, and it led to an increase of glucan recovery in the pretreated solids (above 90%) compared with that of non-extracted quinoa stalks (73–74%). Furthermore, preliminary extraction resulted in enhanced hydrolysis of hemicelluloses and lower by-product formation during pretreatment. The enhancement of hemicelluloses hydrolysis by pre-extraction was more noticeable for SA-HTP than for A-HTP. As a result of the pretreatment, glucan susceptibility towards enzymatic hydrolysis was remarkably improved, and the overall conversion values were higher for the pre-extracted materials (up to 83%) than for the non-extracted ones (64–69%). Higher overall conversion was achieved for the aqueous ethanol-extracted quinoa stalks (72–83%) than for the water-extracted material (65–74%).


2021 ◽  
Vol 316 ◽  
pp. 576-581
Author(s):  
S.A. Layhan ◽  
A.A. Veselovsky

The present study considers various technological approaches to the processes of complex utilization of nickel slags with preliminary additional extraction of non-ferrous metals, iron, and ways of utilization of the obtained gangue. The valuable components are often produced from waste using the mineral acids or mixtures; the metals are extracted from acid solutions in a free form or in the form of compounds using electrochemical or chemical methods. Slag dumps have a heterogeneous structure and mineralization; the zone distribution of slag is clearly defined due to different cooling and solidification rates. The slag composition is mostly represented by dense low-porous varieties consisting of dark brown glass. The porous slag fragments are secondary. The third texture diversity in the composition of slag is represented by nodular and kidney-shaped particles. The diversity and size of the ore minerals is directly connected with the distribution of pores in slag. The major ways for utilization of nickel industrial waste are pyro-metallurgical and hydrometallurgical methods. In addition, each of the methods is usually preceded by the stage of mechanical preparation of the raw materials, where the techno-genic waste is crushed.


2020 ◽  
pp. 227-233
Author(s):  
Vladimir Aleksandrovich Levdansky ◽  
Irina Vladimirovna Korol'kova ◽  
Aleksandr Vladimirovich Levdanskiy ◽  
Boris Nikolayevich Kuznetsov

The isolation of proanthocyanidins from bark of Scotch pine Pínus sylvéstris L. by water and water-alcohol solutions containing 5, 10, 15, 20 and 25% ethanol was studied for the first time. Isolation of proanthocyanidins was carried out from the initial and deresinified (extracted with hexane) pine bark. It was shown that, compared with water extraction, the use of 15–25% aqueous ethanol solutions allows one to increase the yield of proanthocyanidins from 0.44 to 0.63%. It was established that the preliminary extraction of resinous substances from the pine bark does not significantly affect the yield of proanthocyanidins. It was shown that an increase in ethanol concentration of more than 20% in the extraction solution leads to an increase in the total yield of extractives, while the yield of proanthocyanidins does not increase. A study of proanthocyanidins by UV spectroscopy after their conversion to red anthocyanidins showed that they mainly consist of procyanidin and prodelphinidine in close concentrations. The composition of the obtained proanthocyanidins mixtures was studied by IR and 13C NMR spectroscopy. It was shown that the proanthocyanidins obtained from the bark of pine Pínus sylvéstris L., in contrast to isolated from other pine species, contains gallic acid residues which can increase their antiradical activity.


Heritage ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 606-636
Author(s):  
Luigi Barazzetti

This paper presents a workflow for B-rep solid model generation of organic objects using T-splines constructed with quad-meshes. The aim is the creation of geometrically and topologically consistent B-rep solid models of heritage objects featuring organic shapes, which can be used in numerical simulation based on meshless finite element analysis. Point clouds and closed triangular meshes are converted into B-rep solids with a multi-step procedure based on the preliminary extraction of quadrilateral meshes, which are used to produce T-splines. Evaluation of metric quality is carried out to quantify the difference between the final solid and input datasets. A coarse-to-fine approach can also be exploited by varying the quad-mesh resolution to preserve the level of details captured during the digitization process. Finally, meshless finite element analysis can be run with the produced solid bodies. Results for both simulated and real heritage objects are illustrated and discussed.


Author(s):  
А.Г. Гурбанов ◽  
А.Б. Лексин ◽  
В.М. Газеев ◽  
О.А. Гурбанова ◽  
А.Б. Лолаев ◽  
...  

Актуальность исследований: выявлены дополнительные доказательства необхо- димости комплексной утилизации захороненных промышленных отходов с предварительным извлечением из них экономически ценных, включая благородные и экологически опасные метал- лы; выявлена высокая степень загрязнения почв в долине р. Хаником-дон. Цель исследований: на основании геохимических данных определить масштабы и степень загрязнения почв на территории, прилегающей к Фиагдонскому хвостохранилищу. В статье, на основании результатов геохимических исследований почв сельхозугодий (огородов) в поселе- ниях Куыртат и Горный Дзуарикау и природных пастбищ (ПП), проведенных количественными методами (РФА и ICP MS), оценены степень и масштабы их загрязнения промышленными отхо- дами, хранящимися в Фиагдонском хвостохранилище. Впервые приведены данные о содержании экономически ценных и экологически опасных элементов в почвах огородов и природных паст- бищ и рассмотрена геохимическая роль почвообразующих аргиллитов нижнеюрского возраста в формировании почв. Показано, что механизм загрязнения почв обусловлен ветровой эрозией поверхностного слоя хвостохранилища, а затем и из катастрофических воронок на его по- верхности. Кроме того, на основании результатов анализов, показавших резко повышенные содержания в аргиллитах базовых металлов (Fe, Cu, Zn, Ba, Pb, As), высказано предположение о наличии еще одного природного источника загрязнения почв ПП – почвообразующих аргилли- тов, так как в процессе длительного формирования в горных условиях почв ПП они вполне мог- ли обогатиться указанными выше базовыми металлами. Подчеркнуто, что наличие высоких концентраций базовых металлов в нижнеюрской аргиллитовой толще дало возможность пред- полагать, что эти металлы могли быть мобилизованы с помощью механизма «конвективной ячейки», согласно латераль-секреционной гипотезе, из черносланцевой толщи аргиллитов с формированием промышленно значимых рудных жильных тел полиметаллических месторожде- ний Кадат и Какадур. Research relevance: revealed additional evidence of the need for complex disposal of buried industrial waste with preliminary extraction of economically valuable, including noble and environmentally dangerous metals; revealed a high degree of soil contamination in the valley of the Khanikom-don river. Research objective based on geochemical data is to determine the extent and degree of soil contamination in the territory adjacent to the Fiagdon tailing dump. In the article, based on the results of geochemical studies with quantitative methods (XRF and ICP MS) of soils of agricultural lands (orchards) in the Kurtat and Mountain Dzuarikau settlements and from natural pastures, estimated the extent and magnitude of contamination by industrial wastes stored in the Fiagdon tailing dump. Data on the content of economically valuable and environmentally dangerous elements in the soils of vegetable gardens and natural pastures are presented for the fi rst time, and the geochemical role of soil-forming mudstones of the lower Jurassic age in the formation of soils is considered. It is shown that the mechanism of soil contamination is caused by wind erosion of the surface layer of the tailing dump, and then from catastrophic craters on its surface. In addition, based on the results of analyses showing sharply increased content of base metals in mudstones (Fe, Cu, Zn, Ba, Pb, As), it is suggested that there is another natural source of soil contamination of NP - soil-forming mudstones. Because during the long-term formation of NP soils in mountain conditions, they may well have been enriched with the above-mentioned base metals. It is emphasized that the presence of high concentrations of base metals in the lower Jurassic mudstone column made it possible to assume that these metals could be mobilized using the "convective cell" mechanism according to the lateral-secretion hypothesis, from the black-shale mudstone column with the formation of industrially signifi cant ore vein bodies of the Kadat and Kakadur polymetallic deposits.


2019 ◽  
Vol 26 (2) ◽  
pp. 153-157 ◽  
Author(s):  
DT Usmanov ◽  
ShDj Akhunov ◽  
U Khasanov ◽  
VM Rotshteyn ◽  
BSh Kasimov

Detection and analysis of drugs-of-abuse in biological fluids are the essential tasks for the law enforcement, forensic toxicology, doping research and social health. In this work, we developed a surface-ionization mass spectrometry method for direct detection of trace amount of morphine spiked in blank urine. The mass-spectrometric analysis of spiked samples was carried out without preliminary extraction and chromatographic separation. It was found out that the major fragment ions at m/z 144, 146 could be served as indicator lines of morphine spiked in blank urine. Limit of detection of morphine spiked in blank urine was 100 pg (50 ng/ml), and a linear range of calibration curve was more than two orders of magnitude. The spiked samples were also analyzed by gas chromatography–mass spectrometry without preliminary extraction and derivatization procedures. No morphine was found in the spiked samples. The experimental data show that the high selectivity of the surface ionization can be allowed to direct analysis of morphine spiked in blank urine without its preliminary extraction and chromatographic separation.


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