bluuebunny/crossref_metadata_2025 huggingface dataset:
Is It Possible to Innovate Work Organization? Ideas and Inspirations from Coworking Experiences
Authors: Berdicchia Domenico
Published: May 2021

Coworking is a recent phenomenon, but it is spreading and, even more importantly, it is evolving rapidly. It originated as a relatively simple way for freelancers to share work spaces, services and equipment in order to reduce individual costs. In most advanced cases, coworking organizations are turning into organizational settings in which truly novel work arrangements provide interesting new ideas and inspirations about how to bring about not only innovation in job design and work organization, but also a new way to construct individual and organizational identity. In this paper we will briefly describe how most advanced coworking organizations function, and we will reflect on some key elements that characterize them. We will also discuss about whether, and at what conditions, traditional companies and organizations can learn from such experiences.
https://www.puntoorginternationaljournal.org/index.php/PIJ/article/view/90
Authors: Cuénoud Thibault
Published: May 2021

In modern society, entrepreneurial practices have evolved through the emergence of sustainable development (SD), corporate social responsibility (CSR) initiatives, the consolidation of traditional sectors in the social economy (SE) and the rise of social innovation through technological innovation. In addition, advances in information and communication technology (ICT) enable the general public to become more easily involved in organisational transformations. The term ‘crowdsourcing’ applies to projects that are jointly created by project initiators and citizens. This article addresses the question of whether these citizens, that is, ‘crowds’, should become more involved in sustainable financing organisations that seek legitimacy and socioeconomic efficiency. Ultimately, the question concerns the ability of those responsible for sustainable financing to incorporate these new forms of public involvement and provide appropriate financing for societal challenges. Is it possible for these actors to do this? If so, under what conditions, and how will they have to evolve? A longitudinal case study is carried out to develop a regional ethical, solidarity and crowdfunding investment fund in which the role of the public is clearly defined. We identify the range of possibilities in organisational transformations that are taking place amongst sustainable financing actors.
Magnetic Investigation of an Unusual Dissymmetric Binuclear Manganese Carboxylate Complex
Authors: Novitchi Ghenadie , Costes Jean-Pierre , Popovschi Lilia , Shova Sergiu , Gulea Aurelian
Published: May 2021

The magnetic susceptibility (χT) of an unusual dissymmetric binuclear manganese corboxylate complex has been measured from 2 to 300K. The magnetic data which have been fitted with help of the Heisenberg Dirac Van Vleck HDVV spin-exchange Hamiltonian H = − J S 1 S 2 , indicate that an antiferromagnetic interaction equal to J = -0.90(1) cm-1 is present. A correlation between J values and Mn-H2O-Mn angles has been tempted.
Assessment of Kinetic Parameters in the Waters of the Nistru Course in the Section Naslavcea – Dubasari
Authors: Bunduchi Elena , Duca Gheorghe , Viorica Gladchi , Goreaceva Nelli , Mardari Igor
Published: May 2021

The current work represents the results of a monitoring executed on Nistru River waters between October 2003 and September 2005. The water quality was evaluated on the basis of such kinetic indicators as redox state and capacity of inhibition. The obtained results shows that Nistru River water in the segment Naslavcea village – Dubasari barrage are continuously polluted with reducing substances that diminish the H2O2 content, that actually determines the redox state of natural waters and the content of free radicals.
Homo- and Heteronuclear Complexes of Copper (II) with Schiff Base Obtained on the Base of 2-Hydroxy-3-Carboxynaphtaldehyde
Authors: Lazarescu A.G. , T.C. Popa
Published: May 2021

The complexes of general formula Cu(H2L) (II); [CuLn(L)(NO3)(H2O)n] (where H4L=N,NI-bis[2- hydroxy(3-carboxynaphtalidene)]ethylenediamine; Ln: Nd, n=6 (III); Eu, n=4 (IV); Gd, n=6 (V) have been synthesized and investigated by different methods (IR spectroscopy, TG analysis and magnetochemistry). The coordination set of complex generators are Cu(N2O2) and Ln(O8-9). The effective magnetic moment values, μeff, at 300 K are: 1.78 (II), 3.22 (III), 6.44 (V) B.M. The temperature dependence (300-2 K) of magnetic susceptibility of [CuNd(L)(NO3)(H2O)6] indicates the antiferromagnetic interaction between metal ions.
Development of National Emissions Factors for Solid Wastedisposal on Land Greenhouse Gas Source Category of the National Inventional Inventory in the Republic of Moldova
Authors: Tugui Tatiana , Gheorghe Duca , Marius Taranu
Published: May 2021

The paper summarizes the research results on development national emissions factor for the Greenhouse Gas Inventory (GHGI) Source Category “6A Solid Waste Disposal on Land”. The obtained results offer the opportunity to improve the Intergovernmental Panel for Climate Change (IPCC) methodologies and Emission Factors for assessing the GHG emissions originated from waste sector. The article contains relevant information on composition of landfill gases at managed and unmanaged solid waste disposal sites, as well as the municipal solid waste composition results, investigated during one year in the Republic of Moldova: from autumn, 2004 to summer, 2005.
A Thiolato-Bridged Octanuclear Copper(I,II) Mixed- Valence Complex with N,N,S-Tridentate Ligand
Authors: Kotera Takanori , Sugimoto Tsukasa , Mikuriya Masahiro
Published: May 2021

Thiolato-bridged complex [CuI4CuII4(peampt)4Cl8]·2H2O (Hpeampt = 1-(2-pyridylethyl)amino) methylpropane-2-thiol) has been synthesized and characterized by the elemental analysis, IR and UV-vis spectroscopies and magnetic susceptibility measurement. The X-ray crystal structure analysis of this complex shows a localized mixed-valence octanuclear cage structure made up of four trigonal-bipyramidal CuIIN2SCl2, two trigonal CuIS2Cl, and two tetrahedral CuIS2Cl2 coordination sites. Temperature dependence of magnetic susceptibility (4.5— 300 K) shows that a fairly strong antiferromagnetic interaction is operating between the four CuII ions.
Spectroscopic Properties of the Ln-Ge Complexes with Diethylenetriaminepentaacetic Acid
Authors: Smola Sergiy , Rusakova Natalya , Martsinko Elena , Seifullina Inna , Korovin Yuriy
Published: May 2021

Four new heteronuclear lanthanide complexes with general formula [Ge(OH)(μ-HDTPA)LnGe(OH) (μ-DTPA)] (Ln = Sm – Dy) were synthesized and subsequently characterized by different physico- chemical methods. The structures of new compounds have been proposed. In considered complexes the 4f-luminescence of three-charged ions of samarium, europium, terbium and dysprosium is realized at UV-excitation. It is noteworthy that it is the first observation of 4f-luminescence in water solutions of heteronuclear f-p-complexes. The comparison of luminescent characteristics of hetero- and homonuclear landthanide complexes is described and discussed as well.
The Role of the Natural Antioxidants in the Oxihaemoglobin Oxidation and the Diminution of Nitrite Concentration
Authors: Gonţa Maria
Published: May 2021

The paper includes the study of the inhibition of the process of methemoglobinization at oxidation with nitrites in the presence of sodium dihydroxyfumarate (DFH3Na) and resveratrol (3,4’,5-trihydroxystilben). The experimental study was carried out by treatment of the erythrocyte mass by hemolysis and exposure to nitrite. The kinetic investigations were carried out in following conditions: [Resv] = (5.10-5 – 1.10-3) mol/l, [DFH3Na] = 1.10-6 – 5.10-6 mol/l; [HbO2]=1.10-3 mol/l; pH 7,1; t = 370C. The rate of transformation of HbO2 in the presence of resveratrol and DFH3Na was calculated from kinetic curves of consumption of the substrate and formation of MetHb obtained pectrophotometrically (λmax= 540 nm for HbO2 and λmax=630 for MetHb). It has been found out that the introduction of resveratrol and DFH3Na in the system HbO2 – NO2- causes the decrease of the autooxidation factor φ DFH3Na approximately by 1.1 – 2.5 times and φresveratrol by 1.1 – 1.7 times. The time of achievement of the maximum rate of oxidation of HbO2 dζ/dτ (where ζ is the rate of transformation of HbO2 in MetHb) increases while the phase of fast oxidation of HbO2 decreases with increase of content of inhibitors. The process of interaction of nitrites with reducers (such as DFH4, DFH3Na, resveratrol and (+)-catechine) was carried out as well. It has been established that degree of diminishing of the concentration of nitrites in the system RedH2-NO2- decreases as follows: DFH<4DFH3Na<Resv<(+)Catechol.
Investigation of Grape Seed Proanthocyanidins. Achievements and Perspectives
Authors: Kulciţki V. , Vlad P. F. , Duca Gh. , Lupaşcu T.
Published: May 2021

The present paper provides an account of the basic technuques employed in the investigation of the grape seeds proanthocyanidins (condensed tannins). The importance and biological activity properties of these compounds are considered briefly in the introductory part, while isolation and structural investigation of grape seeds proanthocyanidins represent the basic part of the review. The references cover mostly the recent publications related to implementation of modern techniques of investigation, like high performance liquid chromatography (HPLC) and mass spectrometry (MS).
Study on Quantitative Speciation, by BCR Method, of Zinc Content from River Sediments
Authors: Vasile Georgiana , Stanescu Bogdan , Tudor Claudia , Mihaila Elena
Published: May 2021

The present work presents the results obtained during investigation of the zinc content of the water and river sediments in an area polluted by mining activities, to provide information on the mobility and availability of this element. Sediment and water samples have been collected from significant sites in a former mining area in which with some sterile pits, which represent a major environmental hazard.
Influence of Iodinated Oil and Margarine on the Thyroid System of Rats
Authors: Sturza Rodica A. , Deseatnicov Olga I. , Popovici Cristina M. , Gudumac Valentin S. , Nastas Ion
Published: May 2021

Iodine deficiency is the most prevalent micronutrient deficiency in the world today. Food fortification is an important compliment to food-based approaches, and iodine fortification of foods as one of the strategies for the control of iodine deficiency. Manufacturing and consumption of sunflower oil fortified with iodine as well as derivative products on it basis is a perspective direction for elimination of alimentary dependent iodine deficiency disorders. The present work examines morphological changes in the thyroid system of rats at the experimental mercatholile-induced hypothyroidism. As well it determines the influence of iodinated oil and margarine on the thyroid system of rats. It specifies the safe value of iodinated oil and margarine for rats. In-vivo study demonstrated the efficacy of fortification of lipid products with iodine under iodine deficiency status.
Nitrate-Selective Electrodes Based on the Trinuclear Chromium(III) Pivalates
Authors: Revenco Mihail , Martin Mariana , Dayyih Waell A.A.
Published: May 2021

The paper describes the analytical potentialities of the trinuclear chromium(III) complexes as potentiometric ionophores for the construction of electrodes sensitive to the presence of nitrate anion. The electroactive material containing 4,4’-bipyridil was synthesized in situ. The membrane was prepared using dioctylphthalate as a solvent mediator and poly (vinyl chloride) as a polymeric matrix. The electrodes presented a slope of 56 mV/decade, a low limit of detection (3,2.10-6 mol/l), an adequate lifetime (4 months), and suitable selectivity characteristics when compared with other nitrate electrodes. The good parameters of this electrode made possible its application to the determination of nitrate in different types of fertilizers.
Toxicophores and Quantitative Structure -Toxicity Relationships for Some Environmental Pollutants
Authors: Gorinchoy N. N. , Ogurtsov I. Ya. , Tihonovschi A. , Balan I. , Bersuker I. B. , Marenich A. , Boggs J.
Published: May 2021

The electron-conformational (EC) method is employed to reveal the toxicophore and to predict aquatic toxicity quantitatively using as a training set a series of 51 compounds that have aquatic toxicity to fish. By performing conformational analysis (optimization of geometries of the low-energy conformers by the PM3 method) and electronic structure calculations (by ab initio method corrected within the SM54/PM3 solvatation model), the Electron-Conformational Matrix of Congruity (ECMC) was constructed for each conformation of these compounds. The toxicophore defined as the EC sub-matrix of activity (ECSA), a sub-matrix with matrix elements common to all the active compounds under consideration within minimal tolerances, is determined by an iterative procedure of comparison of their ECMC’s, gradually minimizing the tolerances. Starting with only the four most toxic compounds, their ECSA (toxicophore) was found to consists of a 4x4 matrix (four sites with certain electronic and topologic characteristics) which was shown to be present in 17 most active compounds. A structure-toxicity correlation between three toxicophore parameters and the activities of these 17 compounds with R2=0.94 was found. It is shown that the same toxicophore with larger tolerances satisfies the compounds with les activity, thus explicitly demonstrating how the activity is controlled by the tolerances quantitatively and which atoms (sites) are most flexible in this respect. This allows for getting slightly different toxicophores for different levels of activity. For some active compounds that have no toxicophore a bimolecular mechanism of activity is suggested. Distinguished from other QSAR methods, no arbitrary descriptors and no statistics are involved in this EC structure-activity investigation.
Estimation of the Natural Water Self-Purification Capacity from the Kinetic Standpoint
Authors: Duca Gheorghe , Bunduchi Elena , Gladchi Viorica , Romanciuc Lidia , Goreaceva Nelli
Published: May 2021

The current paper contains a synthesis of the processes of chemical auto-purification that take place in natural waters; examples of mechanisms of such processes occurring with participation of dissolved organic matter, oxidants of the biogeochemical cycle of oxygen and of transition metals including copper and iron are presented. The kinetic indicators of natural water quality are presented as well.
Spectrophotometric Studies of Sanguinarine-Β-Cyclodextrin Complex Formation
Authors: Boldescu Veaceslav , Kacso Irina , Bratub Ioan , Duca Gheorghe
Published: May 2021

The main aim of this study was to investigate the influence of pH and the presence of hydrophilic polymer polyvinylpyrrolidone on the formation of sanguinarine-β-cyclodextrin (SANG-β-CD) inclusion complex. Spectrophotometric studies of the SANG-β-CD systems in the presence and without 0.1 % PVP at the pH 5.0 did not show any evidence of the complex formation. However, the same systems showed several obvious evidences at the pH 8.0: the hyperchromic and the hypochromic effects and the presence of the isosbestic point in the region of 200 – 210 nm. The association constants calculated by three linear methods: Benesi-Hildebrand, Scott and Scatchard, were two times higher for the systems with addition of 0.1% PVP than for the systems without it.
Shelf-Life Prediction of Plum Foods Using Antioxidant Activity Indices
Authors: Tatarov Pavel Gh. , Ivanova Raisa A. , Macari Artur V.
Published: May 2021

The reducing activity and radical scavenging activity of hydrosoluble antioxidants in food compositions from plums during the storage were evaluated. The speeds of changing the reducing activity and radical scavenging activity were different. It was observed that the reducing activity diminished by 63.2% after 62...105 days of storage. The same modification of radical scavenging activity determined in vitro was discovered after 110...254 days of storage. Shelf-life of plum foods was calculated using Weibull distribution. The functional relationship of failure probabilities between the reducing and radical scavenging capacities have been detected (r2= 0. 94-0.98).
Phenylethanoid and Iridoid Glycosides from Veronica Chamaedrys L.
Authors: Marchenko Alexandra , Kintia Pavel , Mashcenco Natalia , Bassarello Carla , Piacente Sonia , Pizza Cosimo
Published: May 2021

Three phenylethanoid glycosides (1, 2, 3) and one iridoid glycoside (4) were isolated from aerial parts of Veronica chamaedrys L. (Scrophulariaceae) for the first time. On the basis of spectral analysis, the structures of these compounds were determined to be acteoside (3,4-dihydroxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside) (1), ehrenoside (3,4-dihydroxy-β-phenylethoxy-O-α-L-arabinopyranosyl-(1→2)-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside) (2), chamaedroside (3,4-dihydroxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-α-L-arabinopyranoside) (3) and aucuboside (4).
Aspects Concerning the Photo- and Biodegradation of Benzothiazoles in Aquatic Compartment
Authors: Delort A.-M. , Besse P. , Mailhot G. , Sancelme M. , Combourieu B. , Chorao Ch. , Covaliova O. , Covaliov V. , Bunescu A. , Dragalin I. , Cincilei A. , Tolocichina S.
Published: May 2021

With the scope to provide complete decomposition of benzothiazoles in water environment, two approaches have been applied including the photocatalytic and biodegradation processes. A new type of continuous-action flow-through photocatalytic reactor was developed, in which it is possible to combine the homogeneous and heterogeneous destruction of refractory organic pollutants. The interactions between the different components of the aminobenzothiazole-containing system under the conditions of photo- and biodegradation (light, iron, free and immobilized bacterial strain Rhodococcus rhodochrous) were analysed. The combined systems “Fe ± light +Rh.rhodochrous” are more effective than simple systems.
Synthesis of Triphenylamine-Based Rhombimine Macrocycle by [2+2] Cyclocondensation Reaction between (1R,2R)-Diaminocyclohexane and 4,4’-Diformyl Triphenylamine
Authors: Vacareanu (Stafie) Loredana , Barboiu Virgil , Timpu Daniel , Grigoras Mircea
Published: May 2021

A Schiff base macrocycle with persistent rhomboidal shape was synthesized in excellent yield through [2+2] condensation reaction between (R,R)-1,2-diaminocyclohexane and 4,4’-diformyltriphenylamine. The dimeric macrocylic structure was proved by electrospray ionization mass spectrometry (ESI-MS), 1H-NMR, and FTIR spectroscopy. The complexation properties were evidenced by UV absorption.
Synthesis, Crystal Structure, and Spectral and Magnetic Properties of Chloro-Bridged Chain Complex of Dinuclear Ruthenium(II,III) 3,4,5-Triethoxybenzoate
Authors: Ishida Hideaki , Handa Makoto , Hiromitsu Ichiro , Mikuriya Masahiro
Published: May 2021

A chloro-bridged chain complex constructed from paddlewheel-type dinuclear ruthenium(II,III) carboxylate units, [Ru2{3,4,5-(C2H5O)3C6H2CO2}4Cl]n·1.2nC2H5OH (1·1.2nC2H5OH), was synthesized and characterized by elemental analysis and IR and UV-vis spectroscopies. The single-crystal X-ray analysis showed that the complex forms a zig-zag chain structure, in which the chloroligands bridge the dinuclear units at the axial positions with the Ru1–Cl–Ru2 angle of 120.38(7)°. A broad band around 1144 nm and a band at 475 nm were observed in the diffused reflectance spectra and ascribed to a δ→δ* and a π(RuO, Ru2)→π*(Ru2) transitions, respectively. Temperature dependence of magnetic susceptibility showed that the antiferromagnetic interaction between the dinuclear units is weak (zJ = −0.8 cm−1) with D value of 60 cm−1.
Physical Methods in Chemistry Investigations of the Chemistry Institute of ASM
Authors: Turta Constantin
Published: May 2021

The following classes of compounds are presented: terpenes, cyclic nitrogen compounds, dioximates, carboxylates etc., which have been studied with the participation of experts on physical methods of research - IR, UV-Vis, Atomic, Mössbauer spectroscopy, as well as Mass-spectrometry and Nuclear Magnetic Resonance in the IC ASM. Also, a number of significant scientific results obtained in collaboration of chemists and specialists in physical methods are described.
The School of Ecological Chemistry Founded by Academician Gheorghe Duca
Authors: Lupascu Tudor , Gonta Maria , Gladchi Viorica
Published: May 2021

This review details the most important achievements in the fi eld of ecological chemistry and environmental protection, obtained at the State University of Moldova and Institute of Chemistry of the Academy of Sciences of Moldova. The main research directions are described, as well as main scientific laboratories and centres of these two institutions.
Achievements of the Institute of Chemistry of the Academy of Sciences of Moldova at 50 Years Anniversary
Authors: Lupascu Tudor , Vlad Pavel F. , Aricu Aculina , Cocu Maria
Published: May 2021

This communication deals with the appearance and development of the research in the field of chemistry in the Republic of Moldova; at the beginning - in chemistry sections of Moldovan Branch of the USSR Academy of Sciences and then - at the Institute of Chemistry, founded in 1959. The dynamics of changes in the structure and research subjects is traced. Data are presented concerning the research results in the fi eld of the chemistry of coordination compounds, fine organic synthesis, natural products chemistry, physicochemical analysis, quantum chemistry, mineral resources, chemistry of natural water and purifi cation of waste water, the preparation and utilization of active carbons, and ecological chemistry. A detailed account both of basic research and applied investigation is given. The collaboration of our scientists with their colleagues from abroad is considered. Information is presented related to the scientific schools at our institute, its guidance and laboratory′s leaders. The scientific equipment of the institute is mentioned. The relationship of the institute with higher schools, as well as training of young researchers will be presented.
Synthesis, Crystal Structure and Magnetic Behaviour of Novel 4f-2s Heterometalic One-Dimensional Coordination Polymers on the Base of 2-Furan-Carboxylic Acid
Authors: Melnic Silvia , Prodius Denis , Shova Sergiu , Stoeckli-Evans Helen , Simonov Yurii , Feher Alexandr , Gdaniec Maria , Turta Constantin
Published: May 2021

Nine new complexes with the general formula {[Ln2Ba(α-Fur)8(H2O)4]}n, where Ln = Nd3+, Sm3+, Eu3+, Pr3+, Gd3+, Tb3+, Ho3+, Er3+ and La3+; α-Fur ≡ C4H3OCOO, were synthesized and characterized by IR spectra, magnetism, X-ray single crystal and powder diffractions.
Azoligands as Bridged in Macrocyclic Dinickel Complexes
Authors: Lozan Vasile
Published: May 2021

The coordination chemistry of dinickel macrocyclic hexaamine-dithiophenolate complexes of Robson-type with azoligands is presented in this microreview. All complexes have been characterised by IR-,UV/Visspectroscopy, and X-ray crystallography. The bioctahedral transition metal complexes of the type [(L6)Ni2(μ-L')]+ exhibit a rich coordination chemistry since the active coordination site L' is accessible for a wide range of exogenous coligands.
Synthesys of a Functionalized Tetrahydrofuran Fragment Through Bromination-Cyclization of a Conjugated Diene
Authors: Kulciţki Veaceslav , Cara Marina , Bourdelais Andrea , Schuster Tomas , Baden Daniel
Published: May 2021

Conjugate 1,4-addition of N-bromosuccinimide (NBS) to a diene system, possessing a suitable oxygen functionality, leads to functionalized tetrahydrofuran derivatives, which can be further derivatized into different synthetic targets.
On the Peculiarities of the Ring Contraction Reactions of Homodrimanes via Acid Mediated Epoxide Rearrangement
Authors: Kulciţki Veaceslav , Sîrbu Tatiana , Ungur Nicon
Published: May 2021

A selective rearrangement of a epoxy-homodrimanic substrate is described. Using fluorosulfonic acid at low temperature leads by ring contraction to a perhydrindanic structure. On the contrary, using boron trifluoride-diethyl ether at r.t. selectively brings about angular methyl migration.
Synthesis of Nitrogen-Containing Compounds from Higher Terpenoids
Authors: Aricu Aculina
Published: May 2021

The presence of nitrogen in the molecule is usually accompanied either by the appearance of a new activity or the intensification of original activity characteristic for the native terpenoids. This maintains alive the scientific interest in the synthesis of such compounds. The present communication put into discussion the recently elaborated methods for preparation of the nitrogen-containing terpenic compounds.
Synthetic Strategy for the Preparation of Bioactive Galactoglycerolipids
Authors: Manzo Emiliano , Ciavatta Maria Letizia , Pagano Dario , Fontana Angelo
Published: May 2021

The current communication represents an extended abstract of the presentation delivered on the joint Moldo-Italian seminar “New frontiers in natural product chemistry”, held in the Institute of Chemistry, Academy of Sciences of Moldova on 30 September. A simple and efficient strategy for the synthesis of galactoglycerolipids is provided.
Study Concerning the Corrosive Activity Properties of Monatomic Alcohol-Gasoline Blends
Authors: Cerempei Valerian
Published: May 2021

The paper studies the corrosive activity of the monatomic alcohol (ethanol, butanol) - gasoline mixtures on the materials from which the internal combustion engines are made. The corrosive influence of these blends was determined in dependence of their composition. It was established that the addition of butanol and triethylamine in the ethanol-gasoline mixture essentially reduces the corrosive activity of this mixture.
Physicochemical Properties of the Gasoline and Alcohol Biofuel Mixtures
Authors: Povar I. , Cerempei V. , Pintilie B.
Published: May 2021

The influence of added alcohols, ethanol and butanol, on the main biofuel properties, such as the specific gravity, Reid saturated vapour pressure and distillation curves have been investigated. These properties are intimately related to the fuel composition and their prediction relies on the knowledge of its components characteristics. This research proves the possibility of obtaining fuels with different levels of resistance to detonation, using gasoline with different chemical components and various fractions of alcohols.
Analysis of the Phthalate Content Levels in Wine Products
Authors: Duca Gheorghe , Sturza Rodica , Gaina Boris , Lazacovici Dmitri
Published: May 2021

In the context of studies conducted in the laboratory of National Center for Quality Testing of the Alcoholic Beverages (Republic of Moldova) were included more than 1300 samples of the bottled wine and base-wine for the presence of most widespread and toxic phthalate – dibutylphthalate using modern method of analysis like GC-MS. Results display presences DBP in 85 % of studied samples of wines, i.e. a content of DBP more than LOQ (0.01mg/dm3). Has been determined that contamination of phthalates has a technogenic character, and it is the result of contact with polymeric materials. Optimum conditions of extraction DBP from liquid samples were obtained.
Coordination Compounds of Nickel(II), Copper(II) and Cobalt(II) Based on S-Methylisothiosemicarbazide as Dyes for Thermoplastic Polymers
Authors: Manole Ştefan , Cocu Maria
Published: May 2021

We have researched the color properties of coordination compounds synthesized by us previously [1] (8-(1',2'-naphthyl)-1-R3-methyl-6-thiomethyl-4,5,7-triazaocta-1,3,5,7-tetraenato-1,1'-diolato(-)O, O', N4, N7-M(II), where R=CH3, C6H5, M=Ni, Co, Cu), which can be used for coloring thermoplastic masses. They meet the requirements for use as a pigment for coloring thermoplastic masses.
Synthesis and Photooxygenation of the Methyl Ester of 11-Homodrim-6,8(9)-Diene-12-Oic Acid
Authors: Biriiac Andrei
Published: May 2021

Starting with the methyl 11-homodrim-8-ene-7-oxo-12-oate a two steps synthesis of methyl-11-homodrim-6,8(9)-diene-12-oate was accomplished in 87% overall yield, which on photooxygenation in the presence of tetraphenylporphyrin gave a mixture of methyl esters of 11-homodrim-7-ene-6α,9α-peroxy-12-oic and 11-homodrim-5,8-diene-7-oxo-12-oic acids 21% and 54% yields, respectively.
Ab Initio Study of Chemical Activation and Hydrogenation of White Phosphorus in Reaction with Rhodium Trihydride Complex
Authors: Balan Iolanta I. , Gorinchoy Natalia N.
Published: May 2021

The four-stage mechanism of reaction of the rhodium trihydride complex [(triphos)RhH3] (triphos=1,1,1-tris(diphenylphosphanylmethyl)ethane) with the white phosphorus molecule resulting in the phosphane and the cyclo-P3 complex [(triphos)M(η3-P3] is analyzed on the basis of ab initio calculations of reactants, products, and intermediate complexes of reaction. It is shown that generation of the transient complex [(triphos)RhH(η1:η1-P4)] followed by intramolecular hydrogen atom migration from the metal to one of the phosphorus atoms is the energetically favourable process. Calculations also show that P4 molecule is activated by coordination to the above complex: the metal-bonded P-P edge is broken, and the tetrahedron P4 is opened to form the butterfly geometry. This activation is realized mainly due to the one-orbital back donation of 4d-electron density from the atom of Rh to the unoccupied antibonding triple degenerate t1*-MO of P4.
Physicochemical Properties of the Water Depleted of Heavy Isotopes
Authors: Goncharuk Vladislav V.
Published: May 2021

Data on physicochemical properties of the light water (deuterium concentration is reduced to the ratio D/H = 4 ppm and that of the isotope of oxygen 18 – to the ratio 18O/16O = 750 ppm) have been obtained. They include the melting and boiling points, kinematic viscosity, density, the spin-spin proton relaxation time, self-diffusion coefficients, and the small-angle laser light scattering. An explanation was proposed for the detected significant changes of the light water as compared with the high-resistivity water having geochemically ordinary isotope composition.
Environmentally Friendly Complexones. The Thermodynamic Characteristics of the Formation of Al3+ Ion Complexes with Ethylenediaminedisuccinic Acid in Aqueous Solutions
Authors: Tolkacheva L.N. , Saprunova T.V. , Nikol`skii V.M. , Yakovlev A.A.
Published: May 2021

Complex formation between Al3+ and ethylenediamine - N,N`-disuccinic acid (H4L) was studied at 25°C against the background of 0.1, 0.5, 1.0 N solutions of KNO3 by potentiometry and mathematical modeling. The extrapolation of concentration constants to zero ionic strength was used to calculate the thermodynamic constants of the formation of the AlL–, AlHL complexes using an equation with one individual parameter (logβ0 = 16.27 ± 0.07, 9.19 ± 0.2 respectively).
Synthesis of Spherical Silica Particles with 3-Mercaptopropyl Groups in Their Surface Layer
Authors: Nazarchuk G. І. , Melnyk І. V. , Zub Yu. L.
Published: May 2021

Spherical silica particles were synthesized by modified Stöber method using tetraethoxysilane and 3- mercaptopropyltrimethoxysilane (MPTMS). It was shown that their size (500-760 nm) depends on the nature of the catalyst used in the prehydrolysis of MPTMS (at constant alkoxysilanes ratio). Elemental analysis, thermogravimetry and IR spectroscopy data indicate the presence of thiol groups (2.8 mmol/g) in the surface layer. It was established that obtained nanospherical silica particles can adsorb Ag(I) ions from their acidified aqueous solutions.
Mercury-Contaminated Fish and Essential Fatty Acids: Problems and Solutions
Authors: Cropotova Janna , Popel Svetlana
Published: May 2021

Fish consumption is an important part of human diet due to essential omega-3 fatty acids found naturally in this product. Many researchers from all over the world found that high mercury concentrations in the body reduced the heart-protective effects of the fatty acids in fish oils. People shouldn't be constrained by choosing between the health hazards related to toxins caused by industrial pollution and the nutritional benefits provided by consummation of essential fatty acids contained in oily fish. It is very important to find an alternative natural source of essential omega-3 fatty acids EPA and DHA to restore an optimal ratio between omega-6 and omega-3 fatty acids in the human diet.
(-)-Sclareol Conversion in Ritter's Reaction Conditions
Authors: Kovalskaya S. , Kozlov N. , Aricu A. , Kulcitki V. , Ungur N.
Published: May 2021

The main products of sclareol (1) Ritter’s reaction in mild conditions are (8R,13R)-Labd-14(15)-en-8,13-diacetamide (2) (8R,13S)-Labd-14(15)-en-8,13-diacetamide (3) stereoisomeric on C13 atom and having unrearranged native diol skeleton. We present in the current communication the results of sclareol converting (1) into nitrogen-containing labdanes in the Ritter’s reaction conditions.
Synthesis of Mono-Substituted and Simmetrically 2, 5-Disubstituted 1, 3, 4-Oxadiazoles
Authors: Ribcovskaia Z. , Macaev F.
Published: May 2021

This article is an extended abstract of a communication presented at the Conference Ecological Chemistry 2012.
A Review of Biosorption of Chromium Ions by Microorganisms
Authors: Zinicovscaia Inga
Published: May 2021

Due to its widespread industrial use, chromium has become a serious pollutant in diverse environmental settings. The main source of chromium pollution including the Republic o Moldova is industry. It is a great need to develop new eco-friendly methods of chromium removal. Biosorption of heavy metals is a most promising technology involved in the removal of toxic metals from industrial waste streams and natural waters. This article is an extended abstract of a communication presented at the Conference Ecological Chemistry 2012.
Thermodynamic Stability Relations in the C-H-O System
Authors: Fishtik Ilie
Published: May 2021

Trace elements soil pollution leads to degradation of structure and aggregates stability which promotes the soil erosion and compaction. For more efficient management of the results on the content of trace elements in eroded soils is used the ecological indicators for characterization the accumulation in genetic horizons. The data confirms the soil pollution by erosion, the losses of humus, carbonates, and trace elements in arable carbonatic chernozems of catena. The humus losses in eroded soils consists 52%, the trace elements - 33-35%.
A resposta da política científica e tecnológica à pandemia da COVID-19 / Science and technology policy in the COVID-19 crisis
Authors: Neves Fabrício Monteiro , Sobral Fernanda Antônia
Published: May 2021

Este artigo busca mapear a resposta do Estado brasileiro à pandemia da Covid-19, instalada no país desde março de 2020, levando-se em conta suas instituições do sistema nacional de ciência e tecnologia. Para isso, em um primeiro momento, discutiremos as respostas dadas em outros países, com ênfase no sistema de fomento e no arcabouço institucionalizado de pesquisa. Discutimos, posteriormente, a resposta do governo brasileiro que, desde o início, pôs em questão a real gravidade da situação. Finalmente, mostramos como a capacidade previamente instalada do sistema científico e tecnológico no Brasil, mesmo em contexto governamental de evidente oposição, respondeu, ainda que precariamente, à pandemia. Com isso, o que se quer argumentar é que, a despeito de toda limitação orçamentária e falta de apoio governamental, a existência prévia de uma rede de instituições de ciência e tecnologia possibilitou uma resposta à pandemia.Palavras-chave: Covid-19; política científica, tecnológica e de inovação; pandemia; Sociologia da ciência. ***This article seeks to map the Brazilian state’s response to the Covid-19 pandemic, set up in the country since March 2020, taking into account its institutions of the national science and technology system. To this end, we will first discuss the responses given in other countries, with focus on the funding system and the institutionalized research framework. We will then debate the response of the Brazilian government, which from the beginning questioned the real gravity of the situation. Finally, we show how the previously installed capacity of the scientific and technological system in Brazil, despite evident governmental opposition, responded, even precariously, to the pandemic. The argument is that despite of the budgetary constraints and lack of government support, the previous existence of a network of science and technology institutions enabled a response to the pandemic.Keywords: Covid-19; scientific, technological and innovation policy; pandemic; Sociology of science.
Quando e como uma doença desaparece. A varíola e sua erradicação no Brasil, 1966/1973 / When and how a disease disappears. Smallpox and its eradication in Brazil, 1966/1973
Authors: Hochman Gilberto
Published: May 2021

Este artigo aborda o programa de erradicação da varíola no Brasil (1966-1973), para analisar o fim de doenças e epidemias em contextos locais. O foco recai sobre os antecedentes de um marco específico e crucial desse processo: o anúncio oficial de seu desaparecimento em agosto de 1973 em pleno regime militar. O objetivo do artigo é compreender como as dimensões políticas, científicas e sanitárias se entrecruzaram na pouca repercussão de uma conquista da saúde pública que mobilizou recursos, governos, população e organizações internacionais. O artigo, baseado em fontes primárias e secundárias, está dividido em quatro partes. A primeira discute as questões gerais relativas ao fim de epidemias e desaparecimento de doenças em contextos locais. A segunda apresenta a dinâmica política e sanitária e as características da campanha de erradicação da varíola entre 1966 e 1980, em suas faces internacional e nacional. A terceira discute os desafios, as desconfianças e as incertezas que envolveram a determinação de que a varíola estava eliminada no Brasil do regime militar entre os anos de 1970 e 1973. Na conclusão, retoma-se a questão do término de epidemias e doenças em contextos históricos e nacionais à luz da erradicação da varíola.Palavras-chave: varíola, governo militar, saúde pública, doença, epidemias. ***This article discusses the smallpox eradication program in Brazil (1966-1973) to analyze the end of diseases and epidemics in local contexts. The focus is on the background of a specific and crucial milestone in this process: the official announcement of its disappearance in August 1973 in the midst of the military regime. The objective of the article is to understand how the political, scientific and health dimensions intertwined in the little repercussion of a public health achievement that mobilized resources, governments, populations, and international organizations. The article, based on primary and secondary sources, is divided into four parts. The first discusses general issues related to the end of epidemics and the disappearance of diseases in local contexts. The second presents the political and health dynamics, and the smallpox eradication campaign’s characteristics between 1966 and 1980, in its international and national aspects. The third discusses the challenges, suspicions, and uncertainties that involved the determination that smallpox was eliminated in Brazil, during the military regime, between 1970 and 1973. In the conclusion, ending epidemics and diseases in historical and national contexts is taken up in the light of the eradication of smallpox.Keywords: smallpox, military government, public health, diseases, epidemics.
Pensando num ensino de ciências decolonial a partir da poesia eu-mulher de Conceição Evaristo
Authors: Araújo Bárbara Simões Barreto de , Rocha Davi Maia , Vieira Fábio Pessoa
Published: May 2021

A partir de uma perspectiva decolonial do ensino, este artigo objetiva fazer uma reflexão sobre a dinâmica homogênea do ensino de ciências, a qual se comporta como veículo de reprodução de uma visão de mundo eurocentrada, visando universalizar o conhecimento ocidental em detrimento das demais culturas. Tal objetivo justifica-se na importância de analisarmos o espaço de prestígio que ainda é reservado para a racionalidade científica, a qual é propagada sem a devida contextualização histórico-filosófica. Tomaremos como base a poesia Eu-mulher de Conceição Evaristo, partindo do pressuposto de que um ensino eurocentrado exclui de seu bojo os grupos minorizados, principalmente a mulher negra.
Representações femininas e as lutas pela emancipação por meio da educação e da escrita
Authors: Silva Cassandra Rúbia Marques da , Bastos Luciene Maria Bastos
Published: May 2021

Este trabalho visa discutir as representações femininas e o trajeto histórico da mulher em busca de emancipação mediante a instrução e a escrita. Tal discussão se insere no processo de expansão das fontes e dos objetos históricos. Este trabalho foi fundamentado na abordagem da História Cultural, tendo como referencial teórico fundamental o historiador Roger Chartier. Aqui também se objetiva compreender como as representações contribuíram para a construção dos papeis sociais femininos, bem como entender sua influência na manutenção/ transgressão desses papeis.
Oficina temática
Authors: Woiciechowski Thiago , Eberhart Renata Azambuja
Published: May 2021

As iniciativas de educação em solos devem ser participativas e dinâmicas, evidenciando o solo como recurso natural essencial para a existência do homem. O objetivo deste trabalho foi utilizar práticas pedagógicas no ensino superior, voltadas para a educação em solos, em que alunos da disciplina de Conservação de Solos e Água do curso de Engenharia Florestal participaram de uma oficina temática sobre geotinta, e posteriormente apresentaram os resultados das pinturas em uma exposição didática. As atividades propostas despertaram maior interesse por parte dos envolvidos em estudos do solo e ecotecnologia. Essas práticas representam estratégias de ensino-aprendizagem importantes nas disciplinas de solos florestais.
PLASMA-ASSISTED ADVANCED OXIDATION PROCESS AND NOVEL MATERIALS FOR WATER AND WASTEWATER TREATMENT
Authors: Skіba Margarita , Pivovarov Olexandr
Published: May 2021

The rapid growth in world population brings with it the need for improvement in the current technology for water purification, in order to provide adequate potable water to everyone. The plasma-based advanced oxidation process (AOP) is one of the most widely studied and best developed processes owing to its environmental compatibility, simple structure, efficiencies and ease of operation. In this study, a plasma-based AOP was stably generated using contact non-equilibrium low-temperature plasma and plasma synthesized composite nanomaterials (TiO2/Ag NPs) for water and wastewater purification. The degradation efficiency of the pollutants was determined by UV–Vis absorption spectroscopy. It was found that, due to the simultaneous production of highly reactive species, plasmas can efficiently eliminate pollutants that are difficult to remove using conventional methods. Aqueous solutions of various pollutants were treated by a low-pressure discharge. Experimental results indicated that CNP was effective for degradation azo dye pollutants (methylene blue (MB) and methyl orange MO) and antibiotics (ofloxacin (OFX) and ciprofloxacin (CFX)): МВ and МО were degraded by 98.5% and 97.0%, respectively after 3 min of plasma treatment; OFX and CFX were degraded by ~95.0% and 80.0%, respectively AOP by CNP indicated. The photodegradation of methylene blue catalyzed by plasma synthesized TiO2/Ag was studied under UV irradiation. The degradation (~91%) was obtained with 2.4 g/L TiO2/Ag within 90 min irradiation.
EFFECT OF MELAMINE ACIDIC TREATMENT ON g-C3N4 PHYSICOCHEMICAL PROPERTIES AND CATALYTIC ACTIVITY
Authors: Ivanets Andrei , Prozorovich Vladimir
Published: May 2021

Heterogeneous photocatalysts are widely used for wastewater and natural water treatment from organic pollutants. In this paper, g-C3N4-based photocatalysts were synthesized by thermal condensation of melamine. The effect of melamine pretreatment with acetic acid on the physicochemical properties of g-C3N4 was studied using differential thermogravimetric analysis (DTA-TG), X-ray diffraction (XRD), FT-IR spectroscopy, scanning electron microscopy (SEM), and low-temperature nitrogen adsorption-desorption. The catalytic activity of synthesized photocatalysts was evaluated during the oxidative degradation of Rhodamine B in an aqueous solution under “soft” (type A) and “hard” (type B) UV irradiation.
OPTIMIZATION OF COSTS FOR ORGANIZATION OF A DECENTRALIZED UNDERGROUND SOURCE OF DRINKING WATER
Authors: Driker Yuhim , Mitchenko Тetiana
Published: May 2021

The purpose of this work is to determine the optimal conditions for Kiev and the Kiev region, under which the costs of organizing a decentralized underground source of drinking water, including well construction and the use of a local water purification system, will be minimal.The analysis is based on the results of the processing of database monitoring project Ukrainian Water Society WaterNet «Map of water quality", which as of October 2020 there are 54,8 thousand of the results of analyzes of water samples from different water sources in Ukraine, including 24,8 thousand test results groundwater samples Kiev and Kiev region, who regularly carried out during the last ten years.An assessment was made of the capital and operating costs for the organization of a decentralized underground source of drinking water, depending on the depth of the well and the parameters of water quality at a given depth.In Kiev and Kiev region, within the studied depth range (from 5 to 210 meters), the main pollutants are nitrates, hardness salts, iron and manganese.The value of the cost of treated water is in the range from 0.89 to 1.3 USD/m3. The cost of water treatment reaches its maximum values for the surface layers (above 27.5 meters), where the water is polluted with nitrates.It was found that the optimal well drilling depth is 50 ± 5 m, at which the cost of 1 cubic meter of treated water is up to the level of the requirements of the Nation Sanitary Rules and Norms "Hygienic Requirements for Drinking Water Intended for Human Consumption" (GSanPiN 2.2.4-171-10) is 0.89 USD/m3, for water supply with a capacity of 2 m3/day.
The activity results of the journal "Proceedings of SPSTL SB RAS" for 2019–2020.
Authors: Editorial Article
Published: May 2021

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