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In the qualitative analysis of complex mixtures of unknown composition, a promising direction for increasing the reliability of the identification of substances is the joint use of several simultaneously determined analytical parameters. A combination of chromatographic methods with FTIR spectroscopy, mass spectrometry, or other methods is used. In solving complex analytical problems of industrial nature, it is economically expedient to use only chromatographic methods. In analyzing complex multicomponent mixtures with a high density of peaks in the chromatogram, the precision of the determination of retention time determines the reliability of the identification of substances and of the result of analysis, using identification both directly by the absolute retention time and by relative parameters derived from it (relative retention times, retention indices). The standard deviation of a measurement of the chromatographic retention time is a measure of precision. Experimental chromatographic retention times were obtained for analyzing a mixture by the following scheme: initial isotherm, temperature programming, final isotherm. A sharp increase (by one order of magnitude) in the numerical value of the standard deviation was noted at the step of temperature programming. A regression equation was obtained linking the point estimate of the standard deviation of the retention time and column temperature. The performance characteristic of the regression equation is obtained as a function that enables calculating the total standard uncertainty in the estimate of the standard deviation of the chromatographic retention time. The results can be used to refine chromatographic retention time and indices that ensure the reliable identification of substances.

In this study, a new polyaniline (PANI) derivative, poly[2-(cyclohex-2-en-1-yl)aniline], was synthesized for the first time. It was shown by varying the synthetic parameters that the highest polymer yield was obtained if HNO3 and (NH4)2S2O8 were used. It was found that variation in the conditions for synthesizing poly[2-(cyclohex-2-en-1-yl)aniline] resulted in changes in the optical properties, for example, the PANI derivative obtained in HClO4 medium and in the presence of (NH4)2S2O8 demonstrated the highest luminescence quantum yield (0.05). Using thermogravimetric analysis of poly[2-(cyclohex-2-en-1-yl)aniline], the main three stages of the polymer thermal degradation were identified. Processing of thermogravimetric curves allowed us to calculate the kinetic and thermodynamic parameters of the thermal degradation of the polymer at various heating rates. The use of poly[2-(cyclohex-2-en-1-yl)aniline] as a sensitive material in resistive sensors showed a high response of electrical conductivity to the changes in humidity (% RH) and ammonia concentration in the environment. The presented results demonstrate an efficient method for PANI modification that favors an improvement in solubility, appearance of photoluminescent properties, and broadening the practical application.

Аммиакты әдіс бойынша кальцийнирленген сода алу процесінің белгілі болғанына екі жүз жыл өтсе де, баламалы технологиялармен сенімді бәсекелесуде. Оның негізгі сатысы − аммиакпен қаныққан натрий хлоридінің су ерітіндісінің карбонизациясы (аммонийленген тұздық), күрделі физика-химиялық процестердің жүруі салдарынан жеткілікті зерттелмеген күйінде қалып отыр. Кальцийнирленген сода өндірісінің карбонизациялық бағаналарынан NaHCO3 шөгінділе-рінің натрий хлоридінің аммонизацияланған карбонизацияланған ерітіндісінде ерігіштікке зерттеу жүргізілді. Тәжірибе бағдарламада берілген уақыт созылып, белгілі бір интервалдан кейін сұйықтықтың сынамасын талдауға алды. Тәжірибе аяқталғаннан кейін ерітіндіні төгіп, химиялық талдауға ұшырады.Еритін NaHCO3 мөлшеріне негізінен ерітіндідегі карбонатты иондардың бастапқы концентрациясы, сондай-ақ әсер ету дәрежесі аммиак концентрациясының өсуімен әлсі-рейтін температура әсер етеді. Осы зерттеуде NaHCO3 метастабильдік ерігіштігіне қызығушы-лықты «баяу аймақта» натрий гидрокарбонатының еруін алдын ала карбонизация колоннасында ерітіндінің болуына байланысты елемеуге және оның метастабильдік концентрациясын шекті ретінде қарауға болады. Натрий гидрокарбонаты мен аммонизацияланған тұздық арасындағы тепе-теңдік осы процестің соңғы сатыларына сәйкес келетін жағдайларда ғана жақсы зерттелген . Карбонизацияның бастапқы сатыларында аммонизацияланған, карбонизацияланған ерітіндідегі натрий гидрокарбонатының ерігіштігін эксперименттік зерттеу жыртпалы сипатта болады.

The photoluminescence of carbon quantum dots synthesized from natural honey and mixtures of honey and sugar has been studied. An increase in the sugar content leads to a decrease in the photoluminescence intensity without changing the shape of the luminescence spectrum of these quantum dots aqueous solutions, which is associated with a decrease in the yield of their synthesis in the sugar presence. The discovered effect can be used to detect sugar in honey. When examining five different market samples of flower honey using this method, two of them showed a significant decrease in the photoluminescence intensity. A laboratory test for compliance with GOST 19792-2017 Standard requirements established an excess of the sucrose content in these samples. Luminescent determination of sugar in honey does not require complicated equipment and can be used to develop a new analytical method for determining the sugar content in counterfeit natural honey.

Intramolecular acid-catalyzed cyclization was suggested for the first time for a polyaniline derivative, namely, poly[2-(2-chloro-1-methylbut-2-en-1-yl)aniline] (PClPA), to give hitherto unknown po...

A new approach has been proposed to the synthesis of optically active 4H-3,1-benzoxazine derivatives based on α-amino acids. The target products have been obtained by reaction of o-(cyclopent-1-en-1-yl)aniline with N-Boc-protected amino acids, followed by removal of the protecting group and heterocyclization by the action of dry hydrogen chloride in methylene chloride.

Satellite observations of the Ozone Monitoring Instrument (OMI) for tropospheric sulfur dioxide (SO2) and formaldehyde (HCHO) column mass densities (CMD) are analyzed for the period 2005–2016 over the atmosphere of Kazakhstan. Regarding SO2 the major hot spots relate to regions with high population and large industrial facilities. Such an example is the city of Ekibastuz that hosts the biggest thermal power plants in the country and exhibits the higher SO2 CMD at national level. The annual average CMD in Ekibastuz reaches 2.5 × 10−5 kg/m2, whereas for the rest of the country respective values are 6 times lower. Other hotspots, mostly urban conglomerates such as Almaty and Nur-Sultan, experience high CMDs of SO2 in particular years, such as 2008. One of the main reasons for this behavior is the financial crisis of 2008, forcing the application of alternate heating sources based on cheap low-quality coal. Regarding HCHO, an oxygenated Volatile Organic Compound (VOC), the main hot spot is noticed over the city Atyrau, the oil capital of the country where two massive oil fields are located. The highest HCHO CMD (9 × 1015 molecules/cm2) appears in the summertime due to secondary production as a result of the photo-oxidation of VOCs emitted by industrial sectors, oil refinery plants and vehicles. Strongly elevated HCHO amounts are also observed in Nur-Sultan in 2012 that could be due to the residential coal combustion and vehicle exhaust under poor winter dispersion conditions. Significant reductions in HCHO observed between 2012 and 2015 can be attributed to two significant measures implemented in the country in 2013 that aimed at the improvement of air quality: the introduction of the emission trading system (ETS) for greenhouse gases and Euro-4 standards for new vehicles entering the national vehicle fleet.

Targeting mitochondria with thenoyltrifluoroacetone (TTFA), an inhibitor of Complex II in the respiratory chain, stimulated cisplatin-induced apoptosis in various cell lines in normoxia but not in hypoxia. This can be explained by the elimination of mitochondria involved in triggering apoptotic cell death by mitophagy, either Parkin-dependent or receptor-mediated. Treatment with TTFA alone or in combination with cisplatin did not cause accumulation of PINK1, meaning that under hypoxic conditions cells survive through activation of a receptor-mediated pathway. Hypoxia triggers the accumulation of BNIP3 and BNIP3L (also known as NIX), key participants in receptor-mediated mitophagy. Under hypoxic conditions, stimulation of autophagy, as assessed by the accumulation of lipidated form of LC3 (LC3II), was observed. To exclude the contribution of canonical macroautophagy in LC3II accumulation, experiments were performed using U1810 cells lacking ATG13, a key enzyme of macroautophagy. Despite the absence of ATG13, hypoxia-mediated accumulation of LC3II was not affected, underlying the importance of the receptor-mediated pathway. In order to prove the protective role of BNIP3 against cisplatin-induced apoptosis, BNIP3-deficient A549 cells were used. Surprisingly, a BNIP3 knockout did not abolish hypoxia-induced protection, however, in cells lacking BNIP3, a compensatory upregulation of BNIP3L was detected. Thus, in the absence of BNIP3, mitophagy could be maintained by BNIP3L and lead to cell death suppression due to the elimination of proapoptotic mitochondria. When both BNIP3 and BNIP3L were knocked out, the inhibitory effect of hypoxia on apoptosis was diminished, although not abolished completely. Undoubtedly, receptor-mediated mitophagy is likely to be one of the mechanisms responsible for cell death suppression under hypoxic conditions.

The role of hydrated electrons in sonochemiluminescence (SCL) arising from the single- and multibubble sonolysis of aqueous solutions of $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{2 + }}}}$$ and $${\text{Ru(bpy)}}_{{\text{3}}}^{{{\text{3 + }}}}$$ is revealed. Possible chemiluminescent reactions between ruthenium ions and the products of water sonolysis are considered. A conclusion is drawn concerning the previously unknown formation of eaq upon the single-bubble sonolysis of water and the absence of this product upon multibubble sonolysis.

The oxidation of N-acetyl-2-ethyl-2-methyl-2,3-dihydro-1H-indole with pyridinium chlorochromate, CrO3 · 2 Py, or CrO3 gave N-acetyl-2-ethyl-2-methyl-2,3-dihydro-1H-indol-3-one which was hydrolyzed to 2-ethyl-2-methyl-2,3-dihydro-1H-indol-3-one. The latter was reduced with sodium tetrahydridoborate in ethanol to 3-hydroxy derivative and converted to the corresponding oxime by treatment with hydroxylamine hydrochloride in methanol. Baeyer—Villiger oxidation of 2-ethyl-2-methyl-2,3-dihydro-1H-indol-3-one and Beckmann rearrangement of its oxime were studied.

Increasing crop yields involves the introduction of not only mineral, but also organic fertilizers into the soil. The disposal of manure of large livestock complexes in adjacent fields in combination with irrigation is of particular relevance at present. This allows, on the one hand, to reduce the load on treatment facilities, and, on the other hand, to improve the soil fertility of adjacent farmland. The article presents the results of monitoring the hydrogeological and reclamation state of the lands in the state farm «Roschinsky» in the Sterlitamak district of the Republic of Bashkortostan irrigated with wastewater from the livestock complex. It is revealed that for the periods from 1987 to 1997 irrigation with wastewater caused an increase in the mineralization of soil solutions from 0,007–0,096 to 0,34–0,45 %. The accumulation of sodium, magnesium, calcium, sulfate and chlorine ions in soils took place. The capacity of the soil-absorbed complex decreased from 49,8 to 12,8 mEq/100 g. Under the influence of irrigation with sewage, the chemical composition and salinity of the groundwater underwent significant changes. The content of sulfates (from 20–40 to 150–350 mg/l), chlorine (from 10–20 to 100–200 mg/l), sodium (from 10–50 to 70–100 mg/l) increased. The mineralization increased from 0,6–0,7 to 1,4–2,7 g/l. The deterioration of soil properties was also observed in the subsequent observation period from 2006 to 2010. Exceeding the boundary value of the dry residue for non-saline soil (0,25 %) in the meter soil layer was noted in 2010 at 9 out of 10 observation points, while in 2006 – only at 1 observation point. The total amount of water-soluble salts in a meter layer of soil from 2006 to 2010 increased by 14,2 t/ha, including toxic salts by 9,57 t/ha. To prevent the further development of salinization processes, the disposal of livestock stocks must be alternated with seasonal preventive leaching of the soil against a background of closed horizontal drainage, as well as increasing the area of the irrigated area and including salt-resistant crops in the rotation.

The oil well drilling and oil processing industries are globally the main contaminants of environmental condition caused by human economic activities. Oil spills have a negative impact on the environment, economy, and society. In this research, the effects of oil with different chemical contents on soil types formed in two soil-climatic conditions have been studied. The purpose of this research is to study the change of soil properties by oil pollution. The experiments have been conducted in irrigated and non-irrigated soils of the desert region of the Kashkadarya and Surkhandarya (Uzbekistan). The results have shown that aggregates (0.25; 0.5; 1; 2; 3; 5; 7; 10 mm) which are the important of soil fertility have changed by oil and oil production, and the changes have proven to be temporary. The effect of the 5% and 15% concentrations of oil, engine oil, petrol, kerosene has been studied. The aggregates 0.25 mm and 0.5 mm have the biggest change among aggregates, in fact, aggregates of 0.25 mm at the level of 5% of oil decreased by 27.02%, at the level of 15% of oil decreased by 99.8%, at the level of 5% of kerosene decreased by 2%, at the level of 15% of oil decreased by 98.1%. Aggregates of 0.5 mm at the level of 5% of oil decreased by 6.44%, at the level of 15% of oil decreased by 67.14%, at the level of 5% of kerosene decreased by 12.75%, at the level of 15% of oil decreased by 92.8%. Engine oil and Petrol at levels 5 and 15 have relatively rare changed. Also, as a result of oil and oil pollution, the total carbon dioxide in the soil has grown briefly, which is an anthropogenic carbon and insignificant for soil fertility and humus. As a result, an anthropogenic carbon increased in gray-brown soil (Durisols Technic, WRB) at 0 – 35 cm layer by 0.22%, irrigated meadow-alluvial soil (Fluvisols, WRB) by 0.31%, irrigated gray-brown soil (Durisols Technic, WRB) by 0.44%, irrigated Takyr-meadow soil (Calsisols, WRB) by 0.25%, Takyr soil (Calsisols, WRB) by 0.32%, sandy Desert soil (Durisols Technic, WRB) by 0.21%.

The nitration, oxidative halogenation, and radical bromination and chlorination of 2-ethyl-2-methyl-2,3-dihydro-1H-indole afforded the corresponding nitro, amino, and halo derivatives. The synthesized compounds were evaluated for their antioxidant, antimicrobial, and plant growth regulating activities.

A new method was developed to synthesize 2-amino derivatives of 3,1-benzoxazines and 3,1-benzothiazines on the basis of о-(cyclopent-1-en-1-yl)aniline by heterocyclization of phenyl- and allylurea and thiourea derivatives in the presence of CF3CO2H, H2O2, or Br2.

A new soluble polymer on 2-[(2E)-1-methyl-2-buten-1-yl]aniline and its copolymers with aniline basis have been synthesized in various molar ratios. For all samples, the electrical conductivity, morphology, solubility, electrochemical properties, as well as spectral and molecular mass characteristics have been studied, and a comparative analysis with polyaniline has been carried out. The substituent introduced into the aniline aromatic ring significantly improves the solubility in typical organic solvents of a high molecular weight product. The morphology of the test compounds depends on the co-monomer ratio. As the content of the substituted aniline in the initial mixture increases, the morphology of the polymer changes from the inherent polyaniline fibrous microstructure to the globular one with irregular substituted polyaniline shapes and sizes. Electrochemical study of the samples revealed that the higher the oxidation potential, the wider the band gap (ranging from 2.00 to 2.15). The electrical conductivity decreases in proportion to the increase in the substituted aniline concentration of the initial co-monomer mixture and amounts to 12.5–35.7 × 106 nSm.

The sonochemiluminescence in 10−4 M aqueous solutions of Ru(bpy)3Cl2 was studied in the presence of NaOH and KOH (up to 0.4 M). The observed increase in the steady-state emission intensity from Ru(bpy)32+ as compared with the intensity in neutral solutions was attributed to conversion of H resulting from water sonolysis to eaq. As a result, there is a multiple (>106) change in the concentrations of the sonochemical intermediates Ru(bpy)3+ and Ru(bpy)33+. The reduction of the Ru(bpy)33+ ion with H, which is of low efficiency for the formation of the excited *Ru(bpy)32+ ion, is replaced by reduction with hydrated electron, in which *Ru(bpy)32+ is generated in a high yield. The participation of eaq provides a fivefold increase in the sonochemiluminescence intensity in a key disproportionation reaction: Ru(bpy)3+ + Ru(bpy)33+ → Ru(bpy)32+ + *Ru(bpy)32+. It was shown that chemiluminescence from reduction of intermediate Ru(bpy)33+ with the OH− ion does not make a pronounced contribution to the sonochemiluminescence intensity.

The article considers the possibility of introducing a pentenyl radical into the structure of aromatic amines by the interaction of the latter with piperylene and its chlorine derivatives, 4-chloro-2-pentene and 3,4-dichloro-2-pentene. Direct alkenylation of aniline with piperylene in the presence of Lewis acids leads to C-alkenyl arylamines. The most effective catalyst is AlCl3. Along with the expected 2- and 4-(1-methyl-2-butenyl) anilines, the formation of 2,4-di- and 2,4,6-tri-(1-methyl-2-butenyl) anilines is observed, the latter being virtiually the only product in the reaction with a 5-fold excess of piperylene. In addition to Lewis acids, H3PO4 deposited on kieselguhr or silica gel, as well as polyphosphoric acid, were used to catalyze this reaction. Under the action of these catalysts, ortho- and para-alkenylated anilines are mainly formed, and the yield of the ortho-isomer, reaching 34%, always exceeds the yield of the para-product. It is possible that, under these conditions, N-alkenylation occurs simultaneously with direct C-alkenylation followed by an amino rearrangement. The yield of the 2,4-dialkenyl product does not exceed 8%, and trialkenylated aniline is completely absent. The optimal reaction temperature is in the range of 180-200 °C, at higher temperatures the yield of the target products decreases due to the polymerization of piperylene. Various aniline derivatives are also involved in the reaction with piperylene. When one of the ortho positions in the arylamine molecule is occupied, as in ortho-toluidine or in 2-chloroaniline, a mixture of the three products is formed in comparable amounts. The reaction of meta-toluidine with piperylene also leads to the mixture of three products, and the substitution does not affect the 2-position between the amino and methyl groups. If both ortho-positions are occupied, as in 2-methyl-6-ethylaniline, the reaction is quite successfully under way in the para-position (yield is 61%). To increase the selectivity of the process, the alkylation of aromatic amines is best carried out not by piperylene, but by its chlorine derivatives. The reaction of aniline with 4-chloro-2-pentene takes place in the environment of triethylamine and leads to N-(1-methyl-2-butenyl) aniline with a yield of 80%. Other primary and secondary arylamines react in the same way. The reaction with 3,4-dichloro-2-pentene proceeds under more severe conditions. If the reaction of aromatic amines with 4-chloro-2-pentene is carried out not in triethylamine medium, but in an excess of arylamine itself as a solvent, then not N- but C-substituted products are formed. The reaction proceeds as a consequitive-simultameous process. In the first stage, N-alkenylation occurs with the formation of N-(1-methyl-2-butenyl) arylamine followed by an amino rearrangement of Claisen under the catalytic action of evolved HCl. Alongside with the obvious predominance of ortho-substituted arylamine (64-82%), para-isomers and, in some cases 5-12% of 2,4- or 2,6-disubstituted compounds were found in the reaction products. The amino rearrangement in the interaction of arylamines with 3,4-dichloro-2-pentene proceeds with exceptional ortho-selectivity. Alkyl groups at nitrogen and ortho positions accelerate, and ortho-chloro, para-methyl, 2,4-dimethyl substituents slow down the process, while the meta-methyl group has no significant effect. The same dependence was observed in the case of 4-chloro-2-pentene. Thus, pentenyl fragment can be introduced in various ways into the structure of aromatic amines: by direct interaction with piperylene in the presence of catalysts, N-alkenylation of 4-chloro-2-pentene and 3,4-dichloro-2-pentene in triethylamine medium and reaction of arylamines with chlorine derivatives of piperylene, accompanied by an amino rearrangement of Claisen.

The paper addresses sonochemiluminescence generated by a single bubble levitating in neutral and alkaline aqueous solutions of Ru(bpy)3Cl2. Generally, this sonochemiluminescence was found to obey the rules identified previously for multibubble sonochemiluminescence and to be described by reactions between the Ru(bpy)32+ ion and the radical products Н·, ОН·, and eaq in solution. These products arise in the bubble upon decay of low-temperature plasma and migrate to the solution as the bubble intensively moves and its spherical shape is distorted as a result of a change in the acoustic pressure above and below the stability threshold. Some radicals can also get into the solution from a stationary bubble. The difference from the multibubble sonochemiluminescence is that luminescence intensity has a higher contribution of the re-emission effect of bubble luminescence by Ru(bpy)32+ ions. In solutions with low concentrations of the complex (10–6–10–5 М) and the bubble being stationary, this effect provides up to 2/3 of the total ruthenium emission intensity. It is suggested that the hydrated electrons, which increase the yield of sonochemiluminescence, can be generated upon single-bubble sonolysis of neutral solutions rather than only upon conversion of H atoms in alkaline solutions, as is the case for the multibubble sonochemiluminescence.

It is for the first time that we have obtained emission-line spectra of metal atoms during single-bubble sonoluminescence of metal carbonyl W(CO)6, Mo(CO)6, Cr(CO)6 solutions in dodecane and similar spectra during single- and multibubble sonoluminescence of nanodispersed Cr(CO)6 suspensions in water, 83% H2SO4 and 74% H3PO4. Nanodispersed suspensions with an average particle size of 15–20 nm were obtained through sonodispersing and filtering Cr(CO)6 crystals in water. The method for comparing the intensities of two atomic metal lines made it possible to measure the electronic temperatures achieved in cavitation bubbles under different modes of sonolysis that vary in the range of (4.5–16)·103 K depending on the mode of sonolysis, the type of liquid and saturating gas (He, Ar, Kr) and the acoustic energy entering the solution or suspension. The electronic temperature for multibubble sonoluminescence is, on the average, by (2–2.5)·103 K less than for single-bubble sonoluminescence for all liquids in question.

The effect of hydrated electron scavengers, Cd2+, NO3-, (CH3)2CO, and OH radical scavengers, Cl-, I-, on the intensity of Ru(bpy)32+ ion sonochemiluminescence observed in neutral aqueous solutions of Ru(bpy)3Cl2 was studied. The variation trends in the luminescence intensity due to the action of the scavengers indicated three main reactions sufficient to explain the sonochemiluminescence in a neutral medium. These reactions are the Ru(bpy)32+ reduction and oxidation with the H atom and the OH radical, respectively, and disproportionation of the Ru(bpy)3+ and Ru(bpy)33+ ions thus formed, giving rise to the multibubble sonochemiluminescence emitter, namely, the electronically excited ∗Ru(bpy)32 ion.

Graphical abstract, Highlights • Luminescence of *Ce3+ at Ce4+ sonoreduction by es in H2O and C2H4(OH)2 was found. • This sonochemiluminescence is quenched by the H+ ion, acceptor of a solvated electron. • Sonochemiluminescence of *Ce3+ ion is also registered in aqueous CeCl3 solutions. • In this case Ce4+ is formed at Ce3+ oxidation by OH, then reduced to *Ce3+ by eaq. • In this case the sonochemiluminescence is quenched by both H+ and Br−, OH acceptor., The moving single-bubble sonoluminescence of Ce3+ in water and ethylene glycol solutions of CeCl3 and (NH4)2Ce(NO3)6 was studied. As found, a significant part of intensity of the luminescence (100% with cerium concentration less than 10–4 M) is due to the sonochemiluminescence. A key reaction of sonochemiluminescence is the Ce4+ reduction by a solvated (or hydrated in water) electron: Ce4+ + es (eaq) → *Ce3+. Solvated electrons are formed in a solution via electrons ejection from a low-temperature plasma periodically generated in deformable moving bubble at acoustic vibrations. Reactions of heterolytic dissociation of solvents make up the source of electrons in the plasma. In aqueous CeCl3 solutions, the Ce4+ ion is formed at the oxidation of Ce3+ by OH radical. The latter species originates from homolytic dissociation of water in the plasma of the bubble, also penetrating from the moving bubble into the solution. The sonochemiluminescence in cerium trichloride solutions are quenched by the Br− (acceptor of OH) and H+ ions (acceptor of eaq). In water and ethylene glycol solutions of (NH4)2Ce(NO3)6, the sonochemiluminescence also quenched by the H+ ion. The sonochemiluminescence in CeCl3 solutions is registered at [Ce3+] ≥ 10–5 M. Then the sonochemiluminescence intensity increases with the cerium ion concentration and reaches the saturation plateau at 10–2 M. It was shown that sonophotoluminescence (re-emission of light of bubble plasma emitters by cerium ions) also contributes to the luminescence of Ce3+ in solutions with [Ce3+] ≥ 10–4 M. If the cerium concentration is more than 10–2 M, a third source contributes to luminescence, viz., the collisional excitation of Ce3+ ions penetrating into the moving bubble.

Eukaryotes have evolved various quality control mechanisms to promote proteostasis in the endoplasmic reticulum (ER). Selective removal of certain ER domains via autophagy (termed as ER-phagy) has emerged as a major quality control mechanism. However, the degree to which ER-phagy is employed by other branches of ER-quality control remains largely elusive. Here, we identify a cytosolic protein, C53, that is specifically recruited to autophagosomes during ER-stress, in both plant and mammalian cells. C53 interacts with ATG8 via a distinct binding epitope, featuring a shuffled ATG8 interacting motif (sAIM). C53 senses proteotoxic stress in the ER lumen by forming a tripartite receptor complex with the ER-associated ufmylation ligase UFL1 and its membrane adaptor DDRGK1. The C53/UFL1/DDRGK1 receptor complex is activated by stalled ribosomes and induces the degradation of internal or passenger proteins in the ER. Consistently, the C53 receptor complex and ufmylation mutants are highly susceptible to ER stress. Thus, C53 forms an ancient quality control pathway that bridges selective autophagy with ribosome-associated quality control in the ER., eLife digest For cells to survive they need to be able to remove faulty or damaged components. The ability to recycle faulty parts is so crucial that some of the molecular machinery responsible is the same across the plant and animal kingdoms. One of the major recycling pathways cells use is autophagy, which labels damaged proteins with molecular tags that say 'eat-me'. Proteins called receptors then recognize these tags and move the faulty component into vesicles that transport the cargo to a specialized compartment that recycles broken parts. Cells make and fold around 40% of their proteins at a site called the endoplasmic reticulum, or ER for short. However, the process of folding and synthesizing proteins is prone to errors. For example, when a cell is under stress this can cause a ‘stall’ in production, creating a build-up of faulty, partially constructed proteins that are toxic to the cell. There are several quality control systems which help recognize and correct these errors in production. Yet, it remained unclear how autophagy and these quality control mechanisms are linked together. Here, Stephani, Picchianti et al. screened for receptors that regulate the recycling of faulty proteins by binding to the ‘eat-me’ tags. This led to the identification of a protein called C53, which is found in both plant and animal cells. Microscopy and protein-protein interaction tests showed that C53 moves into transport vesicles when the ER is under stress and faulty proteins start to build-up. Once there, C53 interacts with two proteins embedded in the wall of the endoplasmic reticulum. These proteins form part of the quality control system that senses stalled protein production, labelling the stuck proteins with ‘eat-me’ tags. Together with C53, they identify and remove half-finished proteins before they can harm the cell. The fact that C53 works in the same way in both plant and human cells suggests that many species might use this receptor to recycle stalled proteins. This has implications for a wide range of research areas, from agriculture to human health. A better understanding of C53 could be beneficial for developing stress-resilient crops. It could also aid research into human diseases, such as cancer and viral infections, that have been linked to C53 and its associated proteins.

Aim. Investigation of comparative dissolution kinetics of generic medicinal products containing moxonidine versus reference drug. Material and methods. Objects of the research were film-coated tablets containing moxonidine (INN) in a dose 0.4 mg: a reference drug Physiotens® and 4 generic drugs. In vitro dissolution test of moxonidine from the study drugs was performed using comparative dissolution kinetics test (CDKT). The CDKT was performed in the media with the following pH: 1.2 (1:9 mixture of 0.1 M hydrochloric acid and water), 4.5 (acetate buffer solution, prepared as per State Pharmacopoeia, XIII), and 6.8 (phosphate buffer solution, prepared as per State Pharmacopoeia, XIII). The sampling for dissolved moxonidine was performed 5, 10, 15, 20, and 30 min after the test was started. An high performance liquid chromatography method with ultraviolet detection at 220 nm was used to assay. Results. Within 15 min more that 85% of moxonidine dissolved from the reference drug and all study drugs at pH 1.2; dissolution profiles were similar without calculation of similarity factor f2. Similarly, at pH 4.5 dissolution profiles of study drugs #2 and #3 were similar to that of the reference drug, and the similarity factor f2 was not calculated. However, in case of study drugs #1 and #4 significant differences were observed at a single time point (15 min), which suggests that their dissolution profiles are non-similar to that of the reference drug. Similarity factors f2 were calculated 17.52 and 35.30, respectively (less than 50). At pH 6.8 similarity factors f2 for all study generic drugs were also less than 50 (23.8, 49.8, 38.6, and 35.9), so their dissolution curves were non-similar to that of reference drug. Conclusion. In our study we observed difference in release in vitro of medicinal products containing moxonidines: none of the study drugs was fully similar to the reference drug in all media. The differences observed at pH 6.8 were noteworthy, where the samples had or faster kinetics (study drugs #2 and #3), or slower dissolution kinetics (test drugs #1 and #4). Observed differences in moxonidine release rate may impact absorption of active pharmaceutical ingredient into the blood following drug administration.

We studied a lean propane-butane-air mixture ascending through a round hole of 10-mm diameter, covered by a brass mesh as a single element of the multicellular flame. Gas temperature was measured by the CARS method (Coherent anti-Stokes Raman Scattering) with original software for spectra processing. The vertical and horizontal velocity components were measured by the PIV method (Particle Image Velocimetry). Distributions of heat release intensity and heat fluxes, which cannot be obtained in direct measurements, were estimated using balance relationships in the energy equation. The results were compared with the data obtained for the rich mixture flame in experiments with the same burner. Convective and molecular heat fluxes were considered separately. It was shown that when the rich air mixture with propane-butane burns, the heat flux caused by thermal conductivity reach a maximum at the center of the heat-release zone. Their intensity is substantially lower in comparison with the convective fluxes behind the flame front, which in turn are almost twice as weak as the convective flux in the flame of a lean mixture. The maximal intensities of heat release in the flame of a rich mixture are lower than in the lean one.

The effect solvents have on the processes of rearrangement and elimination in N-(1-methyl-2-butenyl)aniline (I) in the presence of HCl is studied. It is shown that the dependence of the rearrangement and elimination rate constants of (I) · HCl on the nature of solvents are described perfectly by the Koppel–Palm equation, which considers both nonspecific and specific solvation. The inhibitory effect of solvent nucleophilicity is explained by the complexation between (I) · HCl and solvent molecules. Analysis of the (I) · HCl conversion products obtained in a mixed solvent (m-toluidine + nitrobenzene) demonstrates the intermolecular transfer of the allyl moiety, confirming the formation of allyl cations in the Claisen amino rearrangement.

A diagnostic complex for monitoring the position, propagation direction, and angular distribution dispersion of a particle beam planned for application in the Boron Neutron Capture Therapy facility is described in this paper. For the beam position and direction, the precision is, respectively, 0.1 mm and 1 mrad at 10 mA CW H- beam with energy of about 35 keV and a diameter of the order of 10 mm. The energy spread and angular divergence were measured within the accuracy of about 100 eV and 3 mrad, respectively. The acceptable precision of about 1 mm for the beam position is obtained at a relatively short exposure to 10 ms. To increase the radiation intensity of the beam, the addition of various gases was studied. The addition of gas decreases the beam width and increases the negative ions stripping.

The dependence of tumors on glycolysis for ATP generation offers a rationale for therapeutic strategies aimed at selective inhibition of the glycolytic pathway. Analysis of tumor cell responses to anticancer drugs revealed that inhibition of glycolysis by 2-deoxy-D-glucose (2-DG) generally augmented the apoptotic response; however, in HCT116 human colon carcinoma cells, apoptosis was suppressed. A comparison of neuroblastoma SK-N-BE(2) and HCT116 cells revealed, that in contrast to HCT116, in SK-N-BE(2) cells 2-DG alone was able to induce cell death. In SK-N-BE(2) cells the decrease in ATP levels upon treatment with 2-DG was more prominent because in HCT116 cells mitochondria compensated for the loss of ATP caused by glycolysis suppression. In both cells lines 2-DG triggered endoplasmic reticulum (ER) stress, assessed by the accumulation of the marker protein GRP78/BiP. Suppression of ER stress by mannose attenuated the 2-DG-induced apoptotic response in SK-N-BE(2) cells, implying that apoptosis in these cells is a consequence of ER stress induction. In HCT116 cells, ER stress stimulated autophagy, assessed by the accumulation of the lipidated form of LC3. The inhibitor of ER stress mannose attenuated autophagy and reversed 2-DG-mediated suppression of cisplatin-induced apoptosis. When autophagy in HCT116 cells was suppressed by bafilomycin, cisplatin-induced apoptosis was decreased. At the same time, stimulation of autophagy in SK-N-BE(2) cells suppressed cell death. Thus, successful treatment of tumors with conventionally used anticancer drugs should be combined with targeting metabolic pathways involved in the regulation of apoptosis, autophagy, and cellular bioenergetics.

A new version has been proposed for the synthesis of analogs of the known herbicides mecoprop (MCPP) and dichlorprop (2,4-DP) by ozonolysis of chloro derivatives of (pent-3-en-2-yloxy)benzene.

Results of an experimental study of hydrodynamics and diffusion combustion of hydrocarbon jets are presented. Various regimes of instability development both in the jet flame proper and inside the source of the fuel jet are considered. The experiments are performed for the case of subsonic gas jet expansion into the air from a long tube 3.2 mm in diameter in the range of Reynolds numbers from 200 to 13 500. The fuel is the propane–butane mixture in experiments with a cold jet (without combustion) and pure propane or propane mixed with an inert dilutant (CO2 or He) for the jet flame. The mean velocity and velocity fluctuations in the near field of the jet without combustion are measured. Among four possible regimes of cold jet expansion (dissipative, laminar, transitional, and turbulent), three last regimes are investigated. The Hilbert visualization of the reacting flow is performed. The temperature profiles in the near field of the jet are measured by a Pt/Pt–Rh thermocouple. An attached laminar flame is observed in the transitional regime of propane jet expansion from the tube. In the case of combustion of C3H8 mixtures with CO2 or with He in the range of Reynolds numbers from 1900 to 3500, the transitional regime is detected in the lifted flame. Turbulent spots formed in the tube in the transitional regime exert a significant effect on the flame front position: they can either initiate a transition to a turbulent flame or lead to its laminarization.

The sonochemiluminescence spectra of electron-excited ions *[Ru(bpy)3]2+ was registered for the first time during sonolysis of argon saturated aqueous solutions of Ru(bpy)3Cl2 with low concentration. At single-bubble sonolysis, the luminescence band of ruthenium is recorded at a concentration of Ru(bpy)3Cl2 from 10-6 M, and at multibubble from 10-5 M. Possible mechanisms for the appearance of the band of a tris-bipyridyl ruthenium(II) complex on the background of an structureless continuum of water in the spectra of sonoluminescence are analyzed. Based on the results of the comparison of the sonoluminescence spectra of Ru(bpy)3Cl2 aqueous solutions with the sonoluminescence spectra of aqueous solutions of rhodamine B (which has a high quantum yield of photoluminescence) it was established that a possible mechanism of sonophotoluminescence does not play a decisive role in ruthenium sonoluminescence. The effect of radical acceptors (O2, C2H5OH, Cd2+, I-) on ruthenium sonoluminescence is analyzed. The most significant mechanism for the formation of electron-excited ions *[Ru(bpy)3]2+ during sonolysis is the sonochemiluminescence in oxidation-reduction reactions involving [Ru(bpy)3]2+ ions and radical products of sonolysis of water (OH, H, e-aq) in the solution volume.

Photographs and spectra of single-bubble sonoluminescence of a bubble moving in pure water and aqueous solutions of $${\text{Ru}}({\text{bpy}})_{3}^{{2 + }}$$ are obtained. It is shown for ruthenium complex solutions that there are luminescence regions outside the main trajectory of motion of the luminous bubble, which are absent in pure water. The observed spatial localization of these regions confirms that (as we have shown previously) they are caused by sonochemiluminescence of the ruthenium complex in the solution bulk that is secondary relative to the primary sonoluminescence of the bubble.

Selective methylation of aniline and its derivatives with dimethyl carbonate under the action of binder-free micro-, macro-, and mesoporous zeolites FeHY-mmm was performed to obtain N-monomethylanilines.

Single-bubble sonoluminescence of colloidal suspensions in dodecane of SiO2 nanoparticles containing Ln3+ ions (Ce3+, Pr3+, Gd3+, Tb3+) was investigated. Sonoluminescence is achieved by irradiating the suspension with ultrasound (27 kHz) in a spherical standing-wave resonator. As found for all suspensions, the luminescence spectra of an immobile bubble contains a structureless continuum with no characteristic bands or Ln3+ lines, which is associated with the low probability of nanoparticle penetration into the bubble. For suspensions with Tb3+ or Gd3+ ions, the narrow bands (quasi-lines of f-f transitions) of these ions are recorded in the spectra of a bubble moving near the resonator’s centre. This is due to the entry of nanoparticles with Ln3+ ions into a bubble deformed during the motion and collisional electronic excitation of these ions in nonequilibrium bubble plasma. For suspensions with Ce3+ or Pr3+ ions, in the moving single-bubble sonoluminescence spectra, the bands corresponding to luminescent d-f transitions of these ions were not found despite their entry into the bubble similar to that of Tb3+ and Gd3+. This result is explained by much lower probability of collisional excitation during the electronic intershell 4f-5d transition in Ln3+ ions compared to the probability of such excitation upon the intrashell 4f-4f transition.

The ion-exchange properties of terrigenous rocks have been studied, and physicochemical modeling has been used to study the formation of sulfate sodium water in the Volga–Ural Basin of the Russian Plate and the Kartalinskii Basin of the Caucasian hydrogeological folded area. Hydrogeochemical experiments have shown that the exchange-adsorption interaction between gypsum water and adsorbed Na+ of terrigenous rocks in the water–rock system involves many stages, resulting in the accumulation in solution of considerable amounts of Na2SO4 (up to 9–17 g/dm3).

Alzheimer’s disease is a fatal neurodegenerative disorder involving the abnormal accumulation and deposition of peptides (amyloid-β, Aβ) derived from the amyloid precursor protein. Various factors that cause pathology data are revealed, but, at the moment, there is no clear understanding of the processes of plaque formation. This is interesting and actual problem because metals such as zinc, manganese, and others induce Aβ aggregation and fibril formation at high metal concentrations, while low concentration metal ions selectively destabilize the Aβ oligomeric species. In present paper, we report a structural studies of the Co2+ ion binding sites of Aβ fragments in water environment by 1D (1H) and 2D (1H-1H) NMR spectroscopy. According to the observed changes in the NMR spectra that were determined, the cobalt binding center of the Aβ13–23 peptide is associated with the aspartate and glutamine residues. Structural model of cobalt associated with Aβ peptide was obtained.

Soluble electron-donor conducting (co)polymers based on functionalized monomeric anilines have been synthesized and characterized for the first time. It has been shown that there is a good correlation between the results obtained from investigations of the electrochemical properties of polyaniline derivatives by the methods of cyclic voltammetry and on the basis of the temperature dependence of the electrical conductance. The polymer based on 2-(1-methyl-2-buten-1-yl)aniline has the lowest energy level of the highest occupied molecular orbital, which determines the prospects for its use as a donor in the active layer when designing organic solar cells.

A cellular ascending flame is studied in a setup where the fuel/air mixture (volume composition of fuel: propane 75%, butane 25%) outflows through a round hole with a diameter from 10 mm to 40 mm, covered with a brass grid. It is shown that the cells start forming if the mixture composition corresponds to the equivalence ratio of 1.4–1.6, regardless of the initial jet diameter. The flame with a single fixed cell was chosen for contactless measurement of local gas parameters. Gas temperature was measured by CARS (coherent anti-Stokes Raman scattering) with original software for spectra processing. The vertical and horizontal velocity components were measured by PIV (particle image velocimetry) equipment. The data were partially duplicated in experiments using LDA (laser Doppler anemometry). Parameters such as heat release and pressure, which cannot be measured directly, were assessed using the balance ratios in the equations of momentum and energy transfer. It is shown that a zone of increased pressure is formed behind the flame front in the centre of the cell due to the thermal expansion of the combustion products. This causes the curvature of the streamlines of the gas flow through the flame front. The visible contour of the cellular flame complies with an isotherm of ∼1000 K, and the heat release surface is shifted about 0.5 mm downstream. High acceleration (2000–3000 m/s 2 ) and non-uniformity of the gas flow are present near the combustion front.

Chemiluminsecence in the visible spectral region is detected for the first time during oxidation of aniline by an ozone–oxygen mixture in aqueous solutions of hydrochloric acid. The kinetics of changes in the luminescence intensity in the temperature range of 284–327 K is investigated and the activation parameters of the process are determined.