bluuebunny/crossref_metadata_2025 huggingface dataset:
NIĆIFOR PERIĆ METROPOLITAN OF RAŠKA-PRIZREN AND SKENDERIJA (1901–1911)
Authors: NOVAKOV ALEKSANDRA , RADOSAVLJEVIĆ NEDELJKO V.
Published: December 2019

The paper presents biographical data on Nićifor Perić, Metropolitan of Raška-Prizren and Skenderija. It analyzes his role of a religious leader, who also had jurisdiction in the marital and partly hereditary law. A special focus is put on his work concerning the establishment of important church institutions and funds. The paper explains his relationship towards education and one part focuses on the issue of the monastery of Visoki Dečani, especially when the foundation of the Committee for debt settlement and stay of Russian monks there is concerned. The paper also explains the nature of the Metropolitan’s misunderstandings both with the Ottoman authorities and the authorities of the Kingdom of Serbia, because he did not yield in his firm attitude concerning the preservation of church privileges, including the authority over schools. Another focus is on the relationship of the Great Church (Ecumenical Patriarchate) with Metropolitan Nićifor and the events that took place during his rule in the Raška-Prizren and Skenderija Metropolitanate.
CORRESPONDENCE BETWEEN GLIGORIJE JEFTANOVIĆ AND THE GREAT ADMINISTRATIVE AND EDUCATIONAL COUNCIL IN 1919
Authors: BRANKOVIĆ BOŠKO M.
Published: December 2019

The paper follows the correspondence between Gligorije Jeftanović and the Great Administrative and Educational Council in the year 1919. The first part of the text presents the correspondence where the Great Administrative and Educational Council requests an opinion from Jeftanović about the secession of the Serbian Orthodox Church in Bosnia and Herzegovina from the Constantinople Patriarchate and merging with the Serbian Patriarchate. The second part of the text presents the correspondence that concerned Jeftanović’s membership in the Great Administrative and Educational Council and his pre-war position as the Deputy Chairman of the Great Administrative and Educational Council, from which he was removed by the occupation Austro-Hungarian authorities during the First World War and, as he claimed in the correspondence, with the assistance of people from the Great Administrative and Educational Council.
FOREIGN STUDENTS AT THE UNIVERSITY OF BELGRADE AND THEIR INTEREST IN THE HISTORY OF SOUTH SLAVS (1923–1941)
Authors: ČOVIĆ PAULINA
Published: December 2019

The paper examines the schooling of foreign students, holders of the scholarships awarded by the Ministry of Education of the Kingdom of Serbs, Croats and Slovenes/Yugoslavia, at the University of Belgrade between the two World Wars. The first competitions were opened mid 1920s, with those countries which aided the schooling of Yugoslav students at their respective universities being eligible to apply. During the 1930s student exchange continued, in an apparently more extensive and organized manner, only to be extended at the end of the period under review to include countries with which the Kingdom of Yugoslavia, in accordance with the change of foreign policy orientation, established close political and economic relations. Thus, in the beginning, students from France, Great Britain, Czechoslovakia and Poland came to study in Belgrade, whereas, during the years before World War II, students also came from Turkey, Germany and Italy. Scholarship holders most often worked on developing their knowledge of Serbo-Croatian-Slovenian, studied literature and Yugoslav culture in general. Many of them chose to study history, whether as part of their undergraduate or specialist studies. They are the particular focus of this study. The paper is based on unpublished archival sources, periodicals and relevant historiographic literature.
MARKET LOAN AND SAVINGS BANK OF VRANJE: 1926‒1947
Authors: ANTIĆ DEJAN D. , BECIĆ IVAN M.
Published: December 2019

The banking system of the Kingdom of Serbia, and later of the Kingdom of Yugoslavia, was principally characterized by numerous small, local money bureaus. These bureaus were founded with the purpose of providing the necessary capital and profit to their shareholders, as well as offering the ground for the capital placement in times of economic depression. The Market Loan and Savings Bank of Vranje was established in the time of a great financial crisis and is thus an example of the money bureau of the aforementioned nature. Moreover, it is the evidence of how the Great Depression affected the private banking system in the Kingdom of Yugoslavia. This paper is based on archival materials and relevant reference materials from both national and international sources.
ASSOCIATION OF FIGHTERS OF YUGOSLAVIA (1929–1935): IDEOLOGY - PRACTICE - OUTCOME
Authors: DRAGOSAVLJEVIĆ VASILIJE
Published: December 2019

The paper aims to present the process of creation, i.e. organizational and ideological shaping of the veteran movement of the Association of Fighters of Yugoslavia (AFY, Serbian BOJ) and illuminate its role in the context of Yugoslav integrationist forces in the first half of the 1930s. A special focus will be placed on the adoption of ideological constructions of the Organization of Yugoslav Nationalists and contemporary French veteran movements. The paper also sheds light on the complex relations between AFY, the 6 January regime and contemporary, ideologically related political groups, and on the role of ideological conceptions of AFY in the creation of the ideology of the Yugoslav National Movement Zbor.
BATHING IN THE ROMAN PROVINCE: LOCAL CHARACTERISTICS OF BATHS IN MOESIA SUPERIOR
Authors: KUZMANOVIĆ NOVOVIĆ IVANA , JANKOVIĆ MARKO A. , MANOJLOVIĆ NIKOLIĆ VESNA
Published: December 2019

There are approximately 40 Roman baths dating from the 1st to 4th century AD that have been discovered in the territory of Moesia Superior. Most of them were systematically investigated, while some were only indirectly confirmed, either by means of surveys or through epigraphic monuments. The presence and layout of the rooms in these baths points to the conclusion that most activities in the baths of Moesia Superior were similar to those in other parts of the Empire. However, the baths from this territory also show some peculiarities, setting them apart from other parts of the Roman Empire. Although insufficiently investigated and reported on, the portable archaeological finds point to a whole host of activities that were not connected with the bath’s essential function – hygiene and health. Musical instruments, styluses, board game accessories and spindle discs are just some of the objects that illustrate the activities in baths, suggesting that it is not enough to interpret these objects as places for maintaining hygiene, but as centres of social life, or, in the case of private baths, as places for rest and leisure.
ITALIAN DIPLOMACY ON MILAN STOJADINOVIĆ AFTER HIS FALL FROM POWER
Authors: SIMIĆ BOJAN
Published: December 2019

Based on primary sources, memoirs, and the relevant literature, this paper examines the attitude of Italian diplomacy towards Milan Stojadinović, a former Prime Minister and Minister of Foreign Affairs of the Kingdom of Yugoslavia, after his fall from power in February 1939. The abovementioned refers primarily to the Foreign Minister, Count Galeazzo Ciano and Italian envoys in Belgrade Mario Indelli and Francesco Mamelli, but it also includes other diplomats and the Italian press.
NATURAL CONDITIONS AS A FACTOR OF URBANIZATION OF THE LOWER POSAVINA IN THE MIDDLE AGES
Authors: VASIN DEJANA
Published: December 2019

The paper analyzes the influence of the natural environment on the emergence and development of urban settlements located on the lower reaches of the Sava River in the Middle Ages. Medieval people were much more dependent on natural conditions than they are today and, therefore, relief, climate, hydrography, fertility of land and natural resources were of great importance for the formation and development of towns. These factors were extremely important both for their strategic location and for supplying the towns with basic things, either through direct production or trade. That is why it is important to learn about and explain these factors, which comprise the basic preconditions for the locations of settlements and to analyze the opportunities and aggravating circumstances that the lower course of the Sava River provided for the life of the town.
FROM AGRARIAN HISTORY: ON LENTILS AND FAVA BEANS IN MEDIEVAL SERBIA UNTIL THE END OF THE 15th CENTURY
Authors: BOŽANIĆ SNEŽANA
Published: December 2019

The paper analyzes the cultivation and representation of lentils and fava beans in medieval Serbia until the end of the 15th century. Their use in the everyday diet of people was influenced by their high protein content. Serbian medieval sources (typikons, charters) indicate that lentil was an obligatory part of monastic meals. The available information on fava beans is scarce, but it can be concluded that they were used in the diet of the poorest social classes. Turkish census records (defterler) created immediately after the Turkish conquest of Serbian lands illustrate the economic circumstances of the time they were compiled and demonstrate the representation of legumes in the production of the time, prompting their analysis in this paper. The paper further briefly analyzes the works of Greek and Roman authors referring to the cultivation and use of legumes in the diet of people, and their usage in religious purposes. Legumes are also shown in the context of traditional Serbian culture.
STATUS AS PERFORMANCE IN ROMAN SOCIETY
Authors: MORLEY NEVILLE
Published: December 2019

Roman social historians have tended to focus on the choice between the modern terms ‘status’ and ‘class’ to characterise the nature of the groups that made up Roman society. Both these concepts seek to describe antiquity in modern sociological terms rather than relying on the limited perspective of the original actors; each can be seen as problematic, so that in recent years historians have often assumed instead a simpler division between ‘elite’ and ‘non-elite’, and/or avoided the issue by focusing on the dynamics of social relations rather than the nature of social groups. This paper argues for the continuing usefulness of the Weberian idea of status, as a complement to the Marxian idea of class, but with a greater focus on the idea of performance, drawing on the sociology of Erving Goffman and Judith Butler. This emphasises the complexity of status; the way that its performance changes in different contexts, and depends both on the choices of the actor and the expectations of the audience, with judgements about the success of the performance always provisional and changing over time. It concludes with reflections on the ways in which status, understood as ideological power, could have functioned effectively within Roman society as a source of genuine authority.
THE TREATIES OF POŽAREVAC AND THEIR IMPACT ON EUROPE
Authors: HEPPNER HARALD
Published: December 2019

This article focuses on the three treaties which were signed in 1718 in Požarevac between Vienna, Constantinople and Venice. The reason for this is the large and long impact which can be observed until the present day, not only regarding these three powers or the Balkans, but the whole Europe. Although the political, juridical, economic and social consequences of these treaties ended mostly at the end of the First World War, the communication infrastructure, the knowledge culture and the mental effects have kept their actuality since the 18th century until today.
СТАВОВИ О УПОТРЕБИ ПИСАМА НА ТЕРИТОРИЈИ ОПШТИНЕ ШАБАЦ
Authors: Ђурић Срђан
Published: December 2019

У овом раду анализирају се ставови грађана општине Шабац о употреби ћириличког и латиничког писма. Циљ истраживања јесте да се укаже на ставове у вези са службеном и неслужбеном употребом два писма у савременом српском језику. Истраживање се спроводи на основу анонимне анкете, а добијени резултати треба да покажу да ли се предност у употреби даје једном од писама и који су параметри који утичу на избор писма.
Strategi Marketing Public Relations untuk Membangun Citra Innisfree melalui Penggunaan Virtual Reality
Authors: Ramadani Fathia , Sofia Kiki Rizqi
Published: December 2019

This research is about the marketing public relations strategy to build a brand image of Innisfree through the use of Virtual Reality (VR). It is essential to enhance the brand in the middle of intense competition in the beauty industry in Indonesia to gain public interest. This research aims to analyze the marketing public relations strategy to build a brand image of Innisfree through the use of VR. This research uses a qualitative method with a descriptive attribute. The collection of primary data is through in-depth interviews with the internal and external informant, dan secondary literature study. The examination of data credibility is using source triangulation. According to the result from a pull strategy i.e., performed online publications, holding media events, online competition, and carry out the survey directly as well as an online survey.
Triethylammonium halochromates/silica gel: an efficient reagent for oxidative coupling of thiols to disulfides
Authors: Ghammamy Shahriare , Mohammadi Mohammad Kazem , Joshaghani Ali Hassani
Published: December 2019

Triethylammonium halochromates, (C2H5)3NCrO3X, TEAXC (X = Cl, F) are easily synthesized by the reaction of triethylamine with a solution of chromium(VI) oxide in 6M hydrochloric acid, or a solution of chromium(VI) oxide in 40% hydrofluoric acid. These reagents are easily supported on common silica gel and can be used as heterogeneous oxidants. Triethylammonium halochromate(VI) is a versatile reagent for the effective and selective oxidation of organic substrates. Various aliphatic (cyclic and acyclic) and aromatic thiols are converted into the corresponding disulfides by treatment with triethylammonium fluorochromate(VI), (TEACC) or triethylammonium chlorochromate(VI), (TEAFC) supported on silica gel, in excellent yields and under mild reaction conditions.
Dynamic studies of nitrophenols sorption on perfil in a fixed-bed column
Authors: Yaneva Zvezdelina , Marinkovski Mirko , Markovska Liljana , Meshko Vera , Koumanova Bogdana
Published: December 2019

The adsorption of two substituted nitrophenols, namely 4-nitrophenol (4-NP) and 2,4-dinitrophenol (2,4-DNP), from aqueous solutions onto perfil was studied using a fixed bed column. The theoretical solid diffusion control (SDC) model describing single solute adsorption in a fixed bed based on the Linear Driving Force (LDF) kinetic model was successfully applied to the investigated systems. The model parameters of solid diffusion coefficient, DS, axial dispersion coefficient, DL, and external mass transfer coefficient, kf, for the investigated systems were estimated by the means of a best fit approach. Some deviations were found between the predicted and the experimental data which reflect the fact that the assumptions of the model were not quite fulfilled for these experiments. It is necessary to adjust the values of the solid diffusion coefficient, the axial dispersion coefficient and the external mass transfer coefficient in order to obtain a satisfactory agreement between the simulated and the experimental breakthrough curves. A Biot number was used as an indicator for the intarparticle diffusion. The Biot number was found to decrease with the increase of bed depth, indicating that the film resistance increased or the intraparticle diffusion resistance decreased.
Use of zirconium phosphate system as a photocatalyst: Photobleaching of tolonium chloride
Authors: Panwar O. P. , Kumar Anil , Ameta Rameshwar , Ameta Suresh C.
Published: December 2019

Water pollution due to effluents from dyes and printing industries poses a serious problem for aquatic life. Photocatalysis has attracted the attention of chemists all over the world because it is an efficient and ecofriendly process to combat the problem of water pollution. Photocatalytic bleaching of tolonium chloride on zirconium phosphate was carried out in presence of light. The progress of the reaction was monitored spectrophotometrically, and it follows pseudo first order kinetics. The effect of variation of different parameters, like concentration of tolonium chloride, pH, amount of semiconductor and light intensity on the rate of bleaching, was also studied. A tentative mechanism for the photocatalytic bleaching of tolonium chloride has been proposed.
Determination of trace elements in chalcopyrite (CuFeS2) by k0-instrumental neutron activation analysis after matrix elements removal
Authors: Taseska Milena , Makreski Petre , Stibilj Vekoslava , Jaćimović Radojko , Stafilov Trajče , Jovanovski Gligor
Published: December 2019

A method for trace elements determination in chalcopyrite, CuFeS2, by k0-instrumental neutron activation analysis (k0-INAA) was proposed. To avoid the interference of iron and copper as matrix elements, methods for their separation were applied. The copper interferences were eliminated by applying an electrolytic separation method. To eliminate iron interferences, a liquid-liquid extraction procedure by diisopropyl ether (DIPE) in hydrochloric acid solution and determination of trace elements in the aqueous phase were undertaken. The k0-INAA method was applied to determine the content of the investigated elements, making it possible to follow the distribution of even fifty elements (with intermediate/medium and long half-lived radionuclides) in the studied mineral. The important advantage of the proposed method is the possibility to determine the content of several trace elements after Fe and Cu separation. Additionally, the elimination of the matrix elements lowered the limit of detection for some trace elements in the water phase compared to their corresponding values determined by k0-INAA in the powder sample.
QC-CE-pyramid model in the designing of the information system within a company
Authors: Chepujnoska Violeta , Mitreva Elizabeta , Chepujnoski Gjorgji
Published: December 2019

The QC-CE-PYRAMID model (Quality Circle and Cause and Effect in the pyramid’s structure) represents an excellent foundation for designing an efficient information system of quality. All of the business processes can be standardized with standard operative procedures in form of flow charts. This is sublimed in the QC-CE-pyramid model. The standard operative procedure starts with planning the activity and entering data which give information on the initial state. Then, it continues with the activities of the business processes where each phase derives an output data which appears to be an input data for the following operation. In the end, the business process ends with information in form of quality report. According to the pyramid’s structure, we can achieve both vertical and horizontal connection among the employees. Thus, the provision of the quality in the company is accompanied by the information flow according to the standard operative procedures. Having this as an initial point, we have analysed the established information system in the Factory for Rail Vehicles in Veles. By making improvements on the system, we also improved its efficiency as well as effectiveness in regard to the quality of information.
Fuel park wastewater monitoring with UV-Vis spectra and partial least squares models
Authors: Lourenço Nídia D. , Menezes José C. , Pinheiro Helena M. , Diniz David
Published: December 2019

In the context of the high application potentials for on-line and in-line measurements in wastewater quality monitoring, UV-Vis spectrophotometry has received recent attention. In the present work the development of Partial Least Squares (PLS) calibration models for the fast determination of parameters legally required at the discharge of a fuel park wastewater treatment plant was attempted using UV-Vis spectra and the corresponding standard analytical values. A PLS model was developed and validated for Chemical Oxygen Demand (COD) determination with 3.8 mg O2/l RMSEP (root mean squared error of prediction). The models developed for 5-day Biochemical Oxygen Demand (BOD5) and Total Suspended Solids (TSS) were validated (3.5 mg O2/l and 2.9 mg/l RMSEP, respectively), but presented some predictive limitations mainly attributed to the narrow interval of concentration values present in the original dataset.
Obtaining porous quartz sand–glass composite for production of diffusers for water aeration
Authors: Adžiski Ranko , Fidančevska Emilija , Angjuševa Biljana , Vassilev Venceslav , Miloševski Milosav
Published: December 2019

Quartz sand with granulation 0.125 ÷ 0.063 mm and 30 wt% waste TV glass were used for preparation of glass ceramic composites with controlled porosity of 24.4 ± 1.5 %, and interconnected pores with size of 250–400 μm. The production of this composite was realized at 950 ºC/2h. This composite possesses E-modulus and bending strength of 12.0 ± 1.2 GPa and 16.1 ± 1.4 MPa, respectively. The permeability and form coefficient of this porous composite were K0 = 3.22 Da and C0 = 3.92·106 m–1, respectively. This porous composite represents a potential material for production of air diffusers for water aeration.
Polymer composites containing waste dust from power production II. Strength characteristics of composites based on UPR/HIPS polymer system
Authors: Koleva Milena , Vassilev Venceslav , Vassilev Gergo
Published: December 2019

Polymer composite material based on “unsaturated polyester resin/high impact polystyrene” polymer system as matrix and waste dust from power production as filler was studied. The waste was mechanically activated at dry conditions at room temperature for 30 minutes. Strength characteristics – impact, bending and compressive strength – dependance on the waste concentration was determined. The optimal results were achieved at waste concentration of 10 w.%. Morphology observations of filled systems were performed to clarify the influence of the structure on composite’s properties.
Synthesis and investigation of mass spectra of some novel benzimidazole derivatives
Authors: Ibrahim Hassan K. , El-Tamany Sayed H. , El-Shaarawy Reda F. , El-Deen Ibrahim M.
Published: December 2019

2-Substituted benzimidazoles (3) and (4a-c) were prepared via condensation of ethyl 2-thionyl-pyruvate (1) and hydrazidoyl derivatives (2a-c) with o-phenylene diamine in acetic acid. Acetylation of compound (4a) with acetic anhydride yielded the corresponding N-acetyl derivative (5). Treatment of compound 4b with hydrazine hydrate gave the corresponding hydrazino derivative (6). Reaction of 2-[(2-thionyl)acetyl)] benzimidazole (3) with hydrazine hydrate gave the pyrazolyl derivative (7) and hydrazino derivative (8). Alkylation of compound 3 with alkyl halide gave the corresponding 2,3-disubstituled benzimidazoles (9a, b). Pyrrolo[1,2-a] benzimidazole derivatives 10 and 11 were prepared via cyclocondensation of compound 3 with acetic anhydride in presence of AcONa and phosphorus oxychloride. The electron impact mass spectra of both of the above series of compounds have also been recorded and their fragmentation patterns are discussed.
Quantitative analysis of sodium picosulfate in the presence of its alkaline degradation product
Authors: Savić Ivana , Nikolić Goran , Savić Ivan
Published: December 2019

A new procedure for the analytical control of a pharmaceutical formulation by high performance liquid chromatographic (HPLC) is proposed. It allows the simultaneous determination of the major compounds in the formulation of the active compound (sodium picosulfate) and the degradation product (impurity), which slowly degrades by hydrolysis with different concentrations of sodium hydroxide, at different temperatures. Separation of sodium picosulfate from the degradation product was performed using the ZORBAX Eclipse XDB C-18 column, with a mobile phase consisting of phosphate buffer (pH = 7) : acetonitrile 85:15 v/v. The method was validated using the HPLC procedure, evaluating selectivity, accuracy, linearity and precision. The proposed method was successfully applied, with excellent recovery, to the analysis of a pharmaceutical formulation (Sodium picosulfate, Zdravlje-Actavis, Serbia) containing sodium picosulfate.
Phenolic content and antimicrobial potentials of Xylopia aethiopica and Myristica argentea
Authors: Esekhiagbe Mercy , Agatemor Mark-Maria Uzuazokaro , Agatemor Christian
Published: December 2019

The Folin-Ciocalteu method was used to quantify the total phenolics in the aqueous extract of two spices, Xylopia aethiopica and Myristica argentea. A modified agar streak dilution method was used to assess the susceptibility of Escherichia coli and Staphylococcus aureus to the aqueous extracts of the spices. The results showed that high levels of phenolics were present in the extracts. The extracts also showed high-modest antimicrobial activity against the tested bacteria.
A green chemical approach for nitration of aromatic compounds
Authors: Dugar Arpita , Kumar Anil , Ameta Rameshwar , Ameta Suresh C.
Published: December 2019

Photochemical aromatic nitration of phenol and salicylic acid has been carried out in the presence of UV radiations and formation of products has been observed spectrophotometrically. The effect of various operating variables like pH, concentration of nitrite ion, formate ion, phenol and salicylic acid, etc. on the rate of the reaction has also been observed. A tentative mechanism involving NO2· radicals has been proposed for photochemical nitration of phenol and salicylic acid.
Crystal structure of triphenyl(quinolin-8-olato)tin(IV)
Authors: Amini Mostafa M. , Azadmeher Amirreza , Khavasi Hamid Reza , Ng Seik Weng
Published: December 2019

Triphenyl(quinolin-8-olato)tin crystallizes as two symmetry-independent molecules whose metal atoms both exist in a cis-C3SnNO trigonal bipyramidal coordination polyhedron that is 29 % distorted toward a square pyramid. The crystal structure [orthorhombic Pbcn space group], with a 26.701(2), b 10.3555(6), c 31.322(2) Å; V 8660.5(9) Å3] is refined from 5950 I > 2σ(I) Mo–Kα reflections measured at 200 K to an R-index of 0.050.
Photoelectrochemical investigations of thermally formed films on titanium surfaces
Authors: Mickova Irena
Published: December 2019

The semi-conducting and photoelectrical properties of TiO2 films prepared with thermal oxidation of titanium in the temperature range from 200 to 600 ºC were studied. Short theoretical background for application of photocurrent in semiconductor electrochemistry was presented. For all investigated temperatures and times of thermal treatments the semi-conducting properties as photocurrent peaks and band gap energies were determined. At lower temperatures the anodic values of photocurrent peaks confirmed the existence of n-type semiconducting TiO2 films with amorphous structure. With increasing the temperature and time of thermal treatment the development of crystalline structure in the film is followed with small decreasing of band gap energy. For films formed at higher temperatures and longer time of thermal treatment the determined band gap energies are close to the 3 eV that corresponds to the rutile structure of the film.
Liquid phase sintering of dense and porous composites obtained from industrial wastes
Authors: Miloševski Darko , Adjiski Ranko , Fidančevska Emilija
Published: December 2019

Metallurgical slag and waste TV glass hawe been used for fabrication of ceramic-glass composite with a controlled porosity. A dense composite consisted of 70 wt% slag and 30 wt% TV glass sintered at 1000 ºC/2h, with the integral porosity of 16 %, has the E–modulus and bending strength of 26.0±1.6 GPa and 60.8±1.9 MPa, respectively. Slag with granulation of 0.125÷0.063 mm and 20 wt% TV glass, sintered at 950 ºC/2h possesses integral porosity of 37 % and E-modulus and bending strength of 11.86±2 GPa and 23.14±2 MPa, respectively, while the composite with the same composition but with porosity of 65 % possesses E-modulus of 2.1±0.3 GPa and bending strength of 3.0±0.4 MPa. The technical coefficient of thermal expansion of the porous systems is 11.12⋅10–6/ºC. The porous composites have been in thermal equilibrium and acted stable in aggressive media.
Atomic absorption spectrometry in wine analysis
Authors: Stafilov Trajče , Karadjova Irina
Published: December 2019

This article reviews methods for the determination and identification of trace elements in wine by using atomic absorption spectrometry (AAS). Wine is one of the most widely consumed beverages and strict analytical control of trace elements content is required during the whole process of wine production from grape to the final product. Levels of trace elements in wine are important from both points of view: organoleptic – Fe, Cu, Mn and Zn concentrations are directly related to the destabilization and oxidative evolution of wines, and toxicological – toxic elements content should be under the allowable limit, wine identification. The identification of metals in wine is subject of increasing interest since complexation may reduce their toxicity and bioavailability. AAS is one of widely used methods for routine analytical control of wine quality recommended by the International Organization of Vine and Wine. Two main approaches – preliminary sample digestion and direct instrumental measurement combined with AAS for trace element determination in wines are reviewed and discussed. Procedures for various sample pretreatments, for trace element separation and preconcentration are presented. Advances in metal identification studies in wines based on AAS are presented.
Spiroconjugation over a boron atom: facile synthesis, structures and vibrational spectra of crystalline 1,3-disubstituted (propen-1,3-diolato)(oxalato)boron molecules
Authors: Naumov Panče , Naumov Panče , Zugik Minjas , Lee Albert , Ng Seik Weng
Published: December 2019

Preparation of single crystals of spiroconjugated bis-chelated boron compounds containing ligands such as propen-1,3-diolates and oxalate, for application as lasing materials in dye laser technology, is burdened by their insolubility in organic solvents and the high melting temperatures. In this work, on the example of (diphenylpropen- 1,3-diolato)(oxalato)boron (1) it is demonstrated that the solvothermal method can be successfully applied as facile, convenient and fairly inexpensive method to overcome the difficulties with preparation of such materials in single crystalline form directly from boric acid and the ligands. Solid-state IR spectra (recorded at room temperature and low temperature) and Raman spectra (recorded at room temperature) and equilibrium molecular geometries of 1 and three other disubstituted β-ketoboron molecules [RC(O)CHC(O)R'](O2CCO2)B (R = R' = t-butyl, 2; R = methyl, R' = phenyl, 3; R = R' = 2-pyridyl, 4) in the ground electronic states were analyzed in detail, based on HF SCF (HF/3-21G, HF/6-31G), MP2 (MP2/6-31G) and DFT (B3LYP/6-31G) calculations. Minima with spiro-chelated tetrahedral (sp3) BO4 or trigonal-planar (sp2) BO3 coordination were located on the potential energy hypersurfaces for all systems. The tetrahedral structures are more stable relative to the trigonal structures (for example, ~37 kcal mol−1 in the case of 2), accounting for the observation that they represent the actual conformers in the solid state. Vibrational criteria for spectroscopic distinction between trigonal and tetrahedral boron−oxygen coordination geometry are presented.
QSAR study by 1,2,4-triazoles using several physicochemical descriptors
Authors: Dimova Vesna , Perišić-Janjić Nada
Published: December 2019

A QSAR study on the inhibition of Bacillus subtilis and Salmonella enteritidis by 1,2,4-triazoles using several physicochemical descriptors was performed. The 1,2,4-triazoles consist of 18 derivatives with N1-aryl- or N1- heteroaryl substituted rings and having aminomethyl or aminoethyl unit. The 6 best models were selected for the discussion. Initial regression analysis indicated that η plays a dominating role in modelling the activity in all proposed models. The correlation coefficients were 0.80 – 0.99 in all cases, and the standard deviation was below 0.42. Good cross-validation Q2 values were obtained (Q2 > 0.72). The ratio of PRESS/SSY ranges between 0.002–0.169, indicating that all proposed models are reliable QSAR models. A statistically significant result for the bacterial inhibitory activity of the chosen triazole derivatives against S. enteritidis, using the eight descriptors, was not obtained.
Treatment of benzene vapors from contaminated air stream in a laboratory-scale compost biofilter
Authors: Rene Eldon R. , Murthy D. V. S. , Swaminathan T.
Published: December 2019

Biofiltration of process waste–gas streams using microorganisms attached to porous support matrix, at low concentrations and high gas flow rates, has gained importance as a versatile treatment technology ever since the Clean Air Act Amendments (1990), by the US – EPA came into existence. In this study, we evaluated the potential of a laboratory–scale biofilter, inoculated with mixed culture, to remove gas–phase benzene from a synthetic waste gas stream. Experiments were conducted in three different phases, after the acclimatization step, corresponding to empty bed residence times (EBRT) varying between 0.81–2.45 min and benzene concentrations up to 1.7 g/m3. At high concentrations, significant reduction in removal efficiency was observed, which may be due to insufficient biomass in the filter bed to utilize the substrate, or due to substrate inhibition at high concentrations. Removal efficiencies higher than 90% were achieved for inlet benzene loading rates lesser than 40 g/m3hr.
Schiff bases derived from hydroxyaryl aldehydes: molecular and crystal structure, tautomerism, quinoid effect, coordination compounds
Authors: Blagus Anita , Cinčić Dominik , Friščić Tomislav , Kaitner Branko , Stilinović Vladimir
Published: December 2019

During the last 50 years a vast number of structural studies on Schiff bases derived from hydroxyaryl aldehydes and their coordination compounds have been undertaken. In this review we present a systematic and brief overview of the most important discoveries and achievements accomplished in this field. The occurrence of Schiff bases (and their complexes) derived from nine most commonly used hydroxyaryl aldehydes in the Cambridge Structural Database (CSD) has been investigated. Keto-enol tautomerism and intramolecular hydrogen bonding in salicylaldimines and naphthaldimines is discussed, with a comment of the most common errors in determining the correct tautomeric form. Also, the interrelationship of crystal packing and the substituents on the Schiff base is studied. Finally, we give a short overview of conformational differences between free Schiff bases and Schiff bases bonded to metal ions as well as some structural characteristics of Schiff base metal complexes.
Ultrasound assisted process for enhanced interlaminar shear strength of carbon fiber/epoxy resin composites
Authors: Bogoeva-Gaceva Gordana , Heraković Niko , Dimeski Dimko , Stefov Viktor
Published: December 2019

The influence of ultrasonic treatment, applied during the impregnation of carbon fiber bundle by resin system, on interface sensitive properties of carbon fiber/epoxy resin composites has been analyzed. The formation of the network has been followed on model composites containing untreated, oxidized and epoxy sized fibers by Fourier transform infrared microscopy (FTIR-microscopy) and differential scanning calorimetry (DSC). The enhanced interlaminar shear strength (ILSS), found for the composites treated by ultrasound, is attributed to the formation of more homogeneous and dense network, which is especially pronounced for epoxy sized carbon fiber composites.
A new facile synthesis of dimethyl 4-(2-(2,6-bis(methoxycarbonyl)pyridin-4-yl)vinyl) pyridine-2,6-dicarboxylate
Authors: Gu Guoliang , Lu Ming
Published: December 2019

A new facile synthesis of pyridine dicarboxylic acid derivative, dimethyl 4-(2-(2,6-bis(methoxycarbonyl)pyridin-4-yl)vinyl)pyridine-2,6-dicarboxylate (DVDPA), from dimethyl 4-(chloromethyl)pyridine-2,6-dicarboxylate (CMDPA) in presence of nitrogen bases has been described. The influences of different base/CMDPA molar ratio and different nitrogen bases were also investigated. The result has shown that the yield could reach 81 % when triethylamine was used and the molar ratio of base/CMDPA was 2.4. The overall yield of title compound via the three-step synthesis starting from dimethyl 4-(hydroxylmethyl)pyridine-2,6-dicarboxylate (HMDPA) was improved to 69 %.
Immobilization of saccharomyces cerevisiae in novel hydrogels based on hybrid networks of poly(ethylene oxide), alginate and chitosan for ethanol production
Authors: Jovanović-Malinovska Ružica , Cvetkovska Maja , Kuzmanova Slobodanka , Tsvetanov Christo , Winkelhausen Eleonora
Published: December 2019

Hydrogel matrices were designed as hybrid networks of poly(ethylene oxide) (PEO) with natural polymers,alginate or chitosan by UV irradiation. The networks were formulated in the single-stage procedure inwhich the alginate or chitosan were added to the crosslinking reaction solution of PEO, and two-stage procedure,with additional chemical crosslinking of alginate or chitosan. Double-layer hydrogels composed of PEOhydrogel core with entrapped cells and outer natural hydrogel layer were also synthesized. The hydrogels werecharacterized by gel fraction yield and degree of equilibrium swelling as well as by rheological measurements.The production of ethanol by immobilized Saccharomyces cerevisiae was used to test the suitability of the synthesizedhybrid hydrogels to serve as carriers for cell immobilization. The presence of cells affected the mechanicalproperties and the structure of the polymer networks. The best system for immobilization was found to bethe PEO/alginate/Ca, which exhibited high mechanical strength (G′, 830; GF, 93; ESH2O, 15) without affectingthe metabolic functions of the cells. The maximum ethanol yield was 0.42 g/g corresponding to 82 % of thetheoretical yield.
HPLC-DAD-ESI-MSn identification of phenolic compounds in cultivated strawberries from Macedonia
Authors: Kajdžanoska Marina , Gjamovski Viktor , Stefova Marina
Published: December 2019

Strawberry fruits contain phenolic compounds that exhibit antioxidant, anticancer, antiatherosclerotic, antinflammatory and anti-neurodegenerative properties. High-performance liquid chromatography (HPLC) coupled to electrospray ionization mass spectrometric (ESI-MS) detection in the positive and negative ion mode has been used to identify the phenolic compounds in extracts from sixteen different strawberry cultivar fruits from Republic of Macedonia. Photodiode-array detection (DAD) has been used for screening of the different classes of phenolic compounds, whereas MS and MSn fragmentation data were employed for their structural characterization. The phenolic compounds identified were grouped as: ellagic acid and ellagic acid conjugates with sugars, ellagitannins, anthocyanins, flavonols, flavanols, and acylated sugars (feruloyl, caffeoyl and coumaroyl hexoses). Quercetin and kaempferol were the major flavonols found as quercetin 3-O-glucoside, quercetin 3-O-glucuronide, kaempferol 3-O-glucoside, kaempferol 3-O-glucoronide, kaempferol 3-O-malonylglucoside, kaempferol 3-O-acetylglucoside and kaempferol 3-O-coumaroylglucoside. Pelargonidin-3-O-glucoside was the most abundant anthocyanin in all strawberry extracts. Proanthocyanidins were also identified by MSn fragmentation as dimers, trimers and tetramers of (epi)catechin and (epi)afzelechin. This is the first assay of the phenolic profile of the strawberry cultivars in Macedonia, which can be further developed for characterization and evaluation of their quality with regards to their phenolic composition.
Photocatalytic degradation of fast green using nanosized CeCrO3
Authors: Bhati Indu , Punjabi Pinki B. , Ameta Suresh C.
Published: December 2019

Fast green dye has been widely used in histology and cytology. It has been found to have tumorigenic effects in experimental animals, as well as mutagenic effects in both experimental animals and humans. Furthermore, in its undiluted form it poses risks of irritation of eyes, skin, digestive tract, and respiratory tract. For photocatalytic degradation of fast green dye the nano-sized bimetal ternary oxide (CeCrO3) ultrafine powder has been prepared using microwave treatment. It has been characterized by XRD and SEM. The photocatalytic degradation of fast green dye was measured by visible absorption spectroscopy. To obtain the optimal conditions for the dye degradation, the effect of various experimental parameters, i.e. pH, amount of photocatalyst, concentration of dye and light intensity on the rate of reaction was studied. A tentative mechanism for the photocatalytic degradation of fast green was proposed. Photocatalytic degradation of fast green dye followed a pseudo first-order kinetics. It was found that the dye degradation gave the best results at a pH of 7.5, and using a 70 mW·cm–2 light intensity with 0.05 g of nano-sized CeCrO3. At room temperature, the photocatalytic degradation rate constant of fast green dye was k = 4.41·10–4 s–1.
Comparison of methods for solving the vibrational Schrödinger equation in the course of sequential Monte-Carlo-quantum mechanical treatment of hydroxide ion hydration
Authors: Petreska Jasmina , Pejov Ljupco
Published: December 2019

Three numerical methods were applied to compute the anharmonic O–H stretching vibrational frequencies of the free and aqueous hydroxide ion on the basis of one-dimensional vibrational potential energies computed at various levels of theory: i) simple Hamiltonian matrix diagonalization technique, based on representation of the vibrational potential in Simons-Parr-Finlan (SPF) coordinates, ii) Numerov algorithm and iii) Fourier grid Hamiltonian method (FGH).Considering the Numerov algorithm as a reference method, the diagonalization technique performs remarkably well in a very wide range of frequencies and frequency shifts (up to 300 cm–1). FGH method, on the other hand, though showing a very good performance as well, exhibits more significant (and non-uniform) discrepancies with the Numerov algorithm, even for rather modest frequency shifts.
Binding of cadmium to soil humic acid as a function of carboxyl group content
Authors: Anđelković Tatjana , Nikolić Ružica , Bojić Aleksandar , Anđelković Darko , Nikolić Goran
Published: December 2019

The binding of Cd(II) to soil humic acid (HA) at pH 6.5 and in 0.1 mol/L KNO3 ionic medium, was studied by potentiometric titration with a cadmium ion selective electrode. The influence of carboxyl groups in cation-humic interactions was investigated by selective blocking of humic acid carboxyl groups with thionyl chloride and methanol. Infrared spectroscopic analysis confirmed that esterification took place. Differences between underivatized and derivatized HA complexation properties are ascribed to carboxyl groups. The Scatchard plots and incremental formation constants were used to obtain values for Cd-binding constants, for both HAs. The derivatization decreased the number of HA complexing sites by approximately 60 %, which correlates with acid-base properties of both HAs, studied by barium hydroxide and calcium acetate exchange methods. The stability constants for binding at the strongest sites (logKINT) was larger for underivatized HA (5.40) than for derivatized HA (4.92), indicating greater stability in the case when carboxyl groups are involved in complexation reaction.
Investigation of solvent effects on electronic absorption spectra of some substituted 1,2,4-triazoline-3-thiones
Authors: Jankulovska Mirjana , Šoptrajanova Lidija , Spirevska Ilinka , Čolančevska-Ragenoviќ Katica , Ristovski Saško
Published: December 2019

The influence of the polarity of the solvent and hydrogen bonding on the electronic absorption spectra of some previously synthesized substituted 1,2,4-triazoline-3-thiones was studied. The electronic absorption spectra of investigated compounds were recorded in the region from 190 nm to 360 nm in eight protic (water, ethylene glycol, methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol and tert-butanol) and five aprotic (acetonitrile, chloroform, dimethylsulfoxide, dimethylformamide and dioxane) solvents. Their absorption maxima appeared in the region between 250 nm and 260 nm as a result of the electron transitions in the 1,2,4-triazoline-3-thione ring. Using the method of linear solvation energy relationships (LSER), the effects of solvent polarity and hydrogen bonding on the electronic absorption spectra were interpreted. The results have shown that the influence of the aprotic solvents is more significant compared to that of the protic solvents.
Influence of salts and pcr inhibitors on the amplification capacity of three thermostable DNA polymerases
Authors: Davalieva Katarina , Efremov Georgi D.
Published: December 2019

The full potential of PCR as a rapid DNA detection method, is limited by inhibition of thermostable DNA polymerases by components in biological samples and substances used for purification of template DNA. We compared the inhibition effect of blood, phenol and various ions on Taq, Tth and Tne thermostable DNA polymerases prepared by us. The amplification capacity of DNA polymerases was tested on the amplification of a 631 bp fragment of a â- globin gene from a 100 ng DNA template under the optimal PCR buffer. Blood above 1 % (v/v) and phenol above 0.1 % (v/v) inhibited Taq, while Tne and Tth tolerated 10 to 30 times more. The inhibitory effect of ions is lowest for the Tth DNA polymerase, followed by Taq and Tne DNA polymerase. We conclude that the PCR inhibiting effect of some substances to Taq DNA polymerase can be eliminated by the use of a more resistant thermostable DNA polymerase, such as Tth or Tne DNA polymerases.
Cyclic conjugation in benzo-annelated coronenes
Authors: Jeremić Svetlana , Radenković Slavko , Gutman Ivan
Published: December 2019

The cyclic conjugation in benzo-annelated coronenes is studied by means of the energy effect (ef) and π-electron content (EC) of the six-membered rings. Some peculiarities of the π-electron structure of benzo-coronenes, inferred by the Clar aromatic sextet theory, could be tested and verified. A regularity that earlier was discovered in the case of perylene congeners is now shown to hold also for benzo-annelated coronenes: Benzenoid rings that are annelated linearly with regard to the central hexagon H0 of coronene decrease the intensity of cyclic conjugation in H0 and this effect is proportional to the number of linearly annelated rings. A very good linear correlation exists between the ef- and EC-values.
The eccentric connectivity index of armchair polyhex nanotubes
Authors: Saheli Mahboubeh , Ashrafi Ali Reza
Published: December 2019

The eccentric connectivity index ξ(G) of the graph G is defined as ξ(G) = Σu∈V(G) deg(u)ε(u) where deg(u) denotes the degree of vertex u and ε(u) is the largest distance between u and any other vertex v of G. In this paper an exact expression for the eccentric connectivity index of an armchair polyhex nanotube is given.
New azo disperse dyes containing cyclohexanone ring for dyeing polyester and nylon fabrics
Authors: Gaffer Hatem E. , Khalifa Mohamed A. E. , El-Bially Shaima F. , Metwally Mohamed A.
Published: December 2019

Condensation of 2,4-diacarboethoxy-5-hydroxy-3-(4-methoxyphenyl)-5-methyl cyclohexanone (1) with equimolar amounts of hydrazine hydrate and phenyl hydrazine afforded the corresponding 2H-indazole-5-carboxylates 2a and 2b, respectively. Coupling of 2 with diazotized aromatic amines furnished the corresponding azo compounds 3a n. When compound 1 was subjected to the Japp-Klingemann reaction in alkaline medium with diazotized aromatic amines furnished the corresponding hydrazones 4a-g. The treatment of 4a-g with phenyl hydrazine in acetic acid allows the isolation of arylhydrazono derivatives 5a-g. The structures of the dyes were established using analytical and spectral data. Evaluation of the technical properties and color assessment of the dyes were done.