Prediction of optimal coagulant and flocculant dosage for water treatment at surface water intake

Reagent treatment is one of the main methods of source water treatment in water supply plants. Suitable values of coagulant and flocculant doses, as a rule, are selected experimentally, and do not vary depending on seasonal changes in indicators. Therefore, to achieve high efficiency of water treatment, there is a need to determine the doses of coagulant and flocculant for the whole year and for separate seasonal periods in order to compare them. Regression analysis allowed us to quantitatively describe the relationships between turbidity, color, oxidizability and hardness of the source water and reagent doses. At the same time the significance of the influence of the listed indicators on the value of coagulant and flocculant doses was determined. The multifactorial relationship between the water quality indicators at the water source (turbidity, color, oxidizability and general hardness) and the parameters of water treatment processes (dosage of coagulant and flocculant) was studied for both the annual cycle and for specific shorter time periods. Calculation of coagulant and flocculant doses for the entire annual period of the water source in practice, makes it possible to predict suitable doses of reagents before trial coagulation. The equations obtained for individual periods take into account the influence of individual factors, and, therefore, will allow to increase the efficiency of water treatment process control, reduce the consumption of reagents and significantly increase the barrier role of water treatment facilities

Heterogeneous Distribution of Phospholipid Molecular Species in the Surface Culture of <i>Flammulina velutipes</i>: New Facts about Lipids Containing α-Linolenic Fatty Acid

Mycelial fungi grow as colonies consisting of polar growing hyphae, developing radially from spore or inoculum. Over time, the colony develops, hyphae are subject to various exogenous or endogenous stimuli, and mycelium becomes heterogeneous in growth, gene expression, biosynthesis, and secretion of proteins and metabolites. Although the biochemical and molecular mechanisms of mycelium heterogeneity have been the subject of many studies, the role of lipids in colony development and zonality is still not understood. This work was undertaken to extend our knowledge of mycelium heterogeneity and to answer the question of how different lipid molecular species are distributed in the surface colony of the basidial fungus Flammulina velutipes and how this distribution correlates with its morphology. The heterogeneity in the lipid metabolism and lipid composition of the fungal mycelium was demonstrated. According to the real-time PCR and LC-MS/MS results, the expression of genes of PC metabolism, accumulation of phospholipid classes, and degree of unsaturation of PC and PE increased in the direction from the center to the periphery of the colony. The peripheral zone of the colony was characterized by a higher value of the PC/PE ratio and a higher level of phospholipids esterified by linolenic acid. Considering that the synthesis of phospholipids in fungi occurs in different ways, we also conducted experiments with deuterium-labeled phospholipid precursors and found out that the Kennedy pathway is the predominant route for PC biosynthesis in F. velutipes. The zonal differences in gene expression and lipid composition can be explained by the participation of membrane lipids in polar growth maintenance and regulation

Natural Deep Eutectic Solvents for the Extraction of Triterpene Saponins from <i>Aralia elata</i> var. <i>mandshurica</i> (Rupr. & Maxim.) J. Wen

The roots of the medicinal plant Aralia elata are rich in biologically active natural products, with triterpene saponins constituting one of their major groups. These metabolites can be efficiently extracted by methanol and ethanol. Due to their low toxicity, natural deep eutectic solvents (NADES) were recently proposed as promising alternative extractants for the isolation of natural products from medicinal plants. However, although NADES-based extraction protocols are becoming common in routine phytochemical work, their application in the isolation of triterpene saponins has not yet been addressed. Therefore, here, we address the potential of NADES in the extraction of triterpene saponins from the roots of A. elata. For this purpose, the previously reported recoveries of Araliacea triterpene saponins in extraction experiments with seven different acid-based NADES were addressed by a targeted LC-MS-based quantitative approach for, to the best of our knowledge, the first time. Thereby, 20 triterpene saponins were annotated by their exact mass and characteristic fragmentation patterns in the total root material, root bark and root core of A. elata by RP-UHPLC-ESI-QqTOF-MS, with 9 of them being identified in the roots of this plant for the first time. Triterpene saponins were successfully extracted from all tested NADES, with the highest efficiency (both in terms of the numbers and recoveries of individual analytes) achieved using a 1:1 mixture of choline chloride and malic acid, as well as a 1:3 mixture of choline chloride and lactic acid. Thereby, for 13 metabolites, NADES were more efficient extractants in comparison with water and ethanol. Our results indicate that new, efficient NADES-based extraction protocols, giving access to high recoveries of triterpene saponins, might be efficiently employed in laboratory practice. Thus, our data open the prospect of replacing alcohols with NADES in the extraction of A. elata roots

Bioactivity Study of the C60-L-Threonine Derivative for Potential Application in Agriculture

The present paper reports data on the biological activity of nanocompositions based on a C60-L-threonine (C60-Thr) derivative. These nanocompositions promote the nonspecific resistance of plants to the action of stress factors (ultraviolet radiation, pesticides, and phytopathogens). Additionally, we determined the perspectives of the C60-Thr adduct application in the cultivation of plants due to the decrease of the pesticide load on the environment. The biological study of C60-Thr revealed the plant growth-stimulating ability due to its influence on the photosynthetic apparatus activity and antioxidant properties

Prospects of Application of Ultramicroelectrode Ensembles for Voltammetric Determination of Compounds with Close Standard Electrode Potentials and Different Diffusion Coefficients

The spherical diffusion that occurs when using ultramicroelectrodes (i.e., electrodes with a characteristic size of 1–10 µm) contributes to a higher mass transfer rate. This leads to equalization of the depletion rates of the near-electrode layer due to the electrochemical reaction and to the supply of the product from the solution depth. This is the reason why, for ultramicroelectrodes, a limiting size of the spherical layer exists in which the concentration gradient is localized (diffusion layer). Thus, a stationary mass transfer mode is achieved, which is expressed in the sigmoidal CV curve’s shape. In ultramicroelectrode arrays, when the diffusion hemispheres are separated, a steady-state diffusion is realized. However, with a decrease in the interelectrode distance, which leads to the diffusion spheres intersection, a mixed regime arises, which is not fully time-independent. The resulting voltammogram’s shape change can serve as an analytical signal in the study of substances with differing diffusion coefficients, since the diffusion layer growth rate and, consequently, the area of intersection of neighboring spheres, depends on it. This work shows the applicability of voltammetry using ensembles of ultramicroelectrodes operating in the transient mode for the analysis of mixtures of electrochemically active compounds with close electrode reaction parameters, such as exchange currents and electrode potential. Ferrocenemethanol esters are used as an example. The applicability of cyclic voltammetry on the UME array for analysis of mixtures was illustrated by means of finite element modelling. The reliability of the modelling results was experimentally proved for ferrocenemethanol esters with glycine and triglycine

Integrative Proteomics and Metabolomics Analysis Reveals the Role of Small Signaling Peptide Rapid Alkalinization Factor 34 (RALF34) in Cucumber Roots

The main role of RALF small signaling peptides was reported to be the alkalization control of the apoplast for improvement of nutrient absorption; however, the exact function of individual RALF peptides such as RALF34 remains unknown. The Arabidopsis RALF34 (AtRALF34) peptide was proposed to be part of the gene regulatory network of lateral root initiation. Cucumber is an excellent model for studying a special form of lateral root initiation taking place in the meristem of the parental root. We attempted to elucidate the role of the regulatory pathway in which RALF34 is a participant using cucumber transgenic hairy roots overexpressing CsRALF34 for comprehensive, integrated metabolomics and proteomics studies, focusing on the analysis of stress response markers. CsRALF34 overexpression resulted in the inhibition of root growth and regulation of cell proliferation, specifically in blocking the G2/M transition in cucumber roots. Based on these results, we propose that CsRALF34 is not part of the gene regulatory networks involved in the early steps of lateral root initiation. Instead, we suggest that CsRALF34 modulates ROS homeostasis and triggers the controlled production of hydroxyl radicals in root cells, possibly associated with intracellular signal transduction. Altogether, our results support the role of RALF peptides as ROS regulators

Multiplicity dependence of light (anti-)nuclei production in p–Pb collisions at sNN=5.02 TeV

The measurement of the deuteron and anti-deuteron production in the rapidity range −1 < y < 0 as a function of transverse momentum and event multiplicity in p–Pb collisions at √sNN = 5.02 TeV is presented. (Anti-)deuterons are identified via their specific energy loss dE/dx and via their time-of- flight. Their production in p–Pb collisions is compared to pp and Pb–Pb collisions and is discussed within the context of thermal and coalescence models. The ratio of integrated yields of deuterons to protons (d/p) shows a significant increase as a function of the charged-particle multiplicity of the event starting from values similar to those observed in pp collisions at low multiplicities and approaching those observed in Pb–Pb collisions at high multiplicities. The mean transverse particle momenta are extracted from the deuteron spectra and the values are similar to those obtained for p and particles. Thus, deuteron spectra do not follow mass ordering. This behaviour is in contrast to the trend observed for non-composite particles in p–Pb collisions. In addition, the production of the rare 3He and 3He nuclei has been studied. The spectrum corresponding to all non-single diffractive p-Pb collisions is obtained in the rapidity window −1 < y < 0 and the pT-integrated yield dN/dy is extracted. It is found that the yields of protons, deuterons, and 3He, normalised by the spin degeneracy factor, follow an exponential decrease with mass number

Constraining hadronization mechanisms with Λc+\rm \Lambda_{\rm c}^{+}/D0^0 production ratios in Pb-Pb collisions at sNN=5.02\sqrt{s_{\rm NN}} = 5.02 TeV

The production of prompt $\rm \Lambda_{\rm c}^{+}$ baryons at midrapidity ($|y|<0.5$) was measured in central (0-10%) and mid-central (30-50%) Pb-Pb collisions at the center-of-mass energy per nucleon-nucleon pair $\sqrt{s_{\rm NN}} = 5.02$ TeV with the ALICE detector. The $\rm \Lambda_{\rm c}^{+}$ production yield, the $\rm \Lambda_{\rm c}^{+}$/D$^0$ production ratio, and the $\rm \Lambda_{\rm c}^{+}$ nuclear modification factor $R_{\rm AA}$ are reported. The results are more precise and more differential in transverse momentum ($p_{\rm T}$) and centrality with respect to previous measurements. The $\rm \Lambda_{\rm c}^{+}$/D$^0$ ratio, which is enhanced with respect to the pp measurement for $4< p_{\rm T} < 8$ GeV/$c$, is described by theoretical calculations that model the charm-quark transport in the quark-gluon plasma and include hadronization via both coalescence and fragmentation mechanisms