Search results for: phenolic compounds
1234 Catalytic Activity of CU(II) Complex on C(SP3)-H Oxidation Reactions
Authors: Yalçın Kılıç, İbrahim Kani
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In recent years, interest in the synthesis of coordination compounds has greatly increased due to various application areas (such as catalysis, gas storage, luminescence). Dicarboxylic acids are often used in the synthesis of metal complexes. Bis-thiosalicylate derivative ligands contribute to the synthesis of structures of crystal engineering interest, as they can have both rigid and flexible properties. In addition, these ligands have great potential in terms of catalytic applications with the sulfur and oxygen donor atoms in their structures. In this study, we synthesized a Cu(II) complex [Cu(tsaxyl)(phen)2]•CH3OH (where tsaxyl = 2,2'-(1,2-phylenebis(methylene))bis(sulfanedyl)dibenzoate, phen = 1,10-phenantroline) and characterized through X-ray crystallography. The catalytic activities of Cu(II) complex on oxidation of ethylbenzene, cyclohexane, diphenylmethane, p-xylene were performed in acetonitrile with t-BuOOH as the source of oxygen.Keywords: complex, crystallography, catalysis, oxidation
Procedia PDF Downloads 1071233 Adsorption of Phenol and 4-Hydroxybenzoic Acid onto Functional Materials
Authors: Mourad Makhlouf, Omar Bouchher, Messabih Sidi Mohamed, Benrachedi Khaled
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The objective of this study was to investigate the removal of two organic pollutants; 4-hydroxybenzoic acid (p-hydroxybenzoic acid) and phenol from synthetic wastewater by the adsorption on mesoporous materials. In this context, the aim of this work is to study the adsorption of organic compounds phenol and 4AHB on MCM-41 and FSM-16 non-grafted (NG) and other grafted (G) by trimethylchlorosilane (TMCS). The results of phenol and 4AHB adsorption in aqueous solution show that the adsorption capacity tends to increase after grafting in relation to the increase in hydrophobicity. The materials are distinguished by a higher adsorption capacity to the other NG materials. The difference in the phenol is 14.43% (MCM-41), 14.55% (FSM-16), and 16.72% (MCM-41), 13.57% (FSM-16) in the 4AHB. Our adsorption results show that the grafted materials by TMCS are good adsorbent at 25 °C.Keywords: MCM-41, FSM-16, TMCS, phenol, 4AHB
Procedia PDF Downloads 2741232 Preparation of Heterogeneous Ferrite Catalysts and Their Application for Fenton-Like Oxidation of Radioactive Organic Wastewater
Authors: Hsien T. Hsieh, Chao R. Chen, Li C. Chuang, Chin C. Shen
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Fenton oxidation technology is the general strategy for the treatment of organic compounds-contained wastewater. However, a considerable amount of ferric sludge was produced during the Fenton process as secondary wastes, which were needed to be further removed from the effluent and treated. In this study, heterogeneous catalysts based on ferrite oxide (Cu-Fe-Ce-O) were synthesized and characterized, and their application for Fenton-like oxidation of simulated and actual radioactive organic wastewater was investigated. The results of TOC decomposition efficiency around 54% ~ 99% were obtained when the catalyst loading, H2O2 loading, pH, temperature, and reaction time were controlled. In this case, no secondary wastes formed and the given catalysts were able to be separated by magnetic devices and reused again.Keywords: fenton, oxidation, heterogeneous catalyst, wastewater
Procedia PDF Downloads 3611231 Relationship between Structure of Some Nitroaromatic Pollutants and Their Degradation Kinetic Parameters in UV-VIS/TIO2 System
Authors: I. Nitoi, P. Oancea, M. Raileanu, M. Crisan, L. Constantin, I. Cristea
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Hazardous organic compounds like nitroaromatics are frequently found in chemical and petroleum industries discharged effluents. Due to their bio-refractory character and high chemical stability cannot be efficiently removed by classical biological or physical-chemical treatment processes. In the past decades, semiconductor photocatalysis has been frequently applied for the advanced degradation of toxic pollutants. Among various semiconductors titania was a widely studied photocatalyst, due to its chemical inertness, low cost, photostability and nontoxicity. In order to improve optical absorption and photocatalytic activity of TiO2 many attempts have been made, one feasible approach consists of doping oxide semiconductor with metal. The degradation of dinitrobenzene (DNB) and dinitrotoluene (DNT) from aqueous solution under UVA-VIS irradiation using heavy metal (0.5% Fe, 1%Co, 1%Ni ) doped titania was investigated. The photodegradation experiments were carried out using a Heraeus laboratory scale UV-VIS reactor equipped with a medium-pressure mercury lamp which emits in the range: 320-500 nm. Solutions with (0.34-3.14) x 10-4 M pollutant content were photo-oxidized in the following working conditions: pH = 5-9; photocatalyst dose = 200 mg/L; irradiation time = 30 – 240 minutes. Prior to irradiation, the photocatalyst powder was added to the samples, and solutions were bubbled with air (50 L/hour), in the dark, for 30 min. Dopant type, pH, structure and initial pollutant concentration influence on the degradation efficiency were evaluated in order to set up the optimal working conditions which assure substrate advanced degradation. The kinetics of nitroaromatics degradation and organic nitrogen mineralization was assessed and pseudo-first order rate constants were calculated. Fe doped photocatalyst with lowest metal content (0.5 wt.%) showed a considerable better behaviour in respect to pollutant degradation than Co and Ni (1wt.%) doped titania catalysts. For the same working conditions, degradation efficiency was higher for DNT than DNB in accordance with their calculated adsobance constants (Kad), taking into account that degradation process occurs on catalyst surface following a Langmuir-Hinshalwood model. The presence of methyl group in the structure of DNT allows its degradation by oxidative and reductive pathways, while DNB is converted only by reductive route, which also explain the highest DNT degradation efficiency. For highest pollutant concentration tested (3 x 10-4 M), optimum working conditions (0.5 wt.% Fe doped –TiO2 loading of 200 mg/L, pH=7 and 240 min. irradiation time) assures advanced nitroaromatics degradation (ηDNB=89%, ηDNT=94%) and organic nitrogen mineralization (ηDNB=44%, ηDNT=47%).Keywords: hazardous organic compounds, irradiation, nitroaromatics, photocatalysis
Procedia PDF Downloads 3171230 Mathematical Modeling of Cell Volume Alterations under Different Osmotic Conditions
Authors: Juliana A. Knocikova, Yann Bouret, Médéric Argentina, Laurent Counillon
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Cell volume, together with membrane potential and intracellular hydrogen ion concentration, is an essential biophysical parameter for normal cellular activity. Cell volumes can be altered by osmotically active compounds and extracellular tonicity. In this study, a simple mathematical model of osmotically induced cell swelling and shrinking is presented. Emphasis is given to water diffusion across the membrane. The mathematical description of the cellular behavior consists in a system of coupled ordinary differential equations. We compare experimental data of cell volume alterations driven by differences in osmotic pressure with mathematical simulations under hypotonic and hypertonic conditions. Implications for a future model are also discussed.Keywords: eukaryotic cell, mathematical modeling, osmosis, volume alterations
Procedia PDF Downloads 4621229 Pharmacological Activities and Potential Uses of Cyperus Rotundus: A Review
Authors: Arslan Masood Pirzada, Muhammad Naeem, Hafiz Haider Ali, Muhammad Latif, Aown Sammar Raza, Asad Hussain Bukhari, Muhammad Saqib, Muhammad Ijaz
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Cyperus rotundus (Cyperaceae), a medicinal herb, is being traditionally used as a home remedy for the treatment of various clinical conditions like diarrhea, diabetic, pyretic, inflammation, malaria, and for treating stomach and bowel disorders. Its current status is one of the most widespread, troublesome, and economically damaging agronomic weeds, growing wildly in various tropical and sub-tropical regions of the world. Tuber and rhizomes of Cyperus rotundus possess a higher concentration of active ingredients in the form of essential oils, phenolic acids, ascorbic acids and flavonoids, responsible for its remedial properties. Exploitation of any medicinal plant application depends on the crucial and comprehensive information about the therapeutic potential of a plant. Researchers have evaluated and characterized the significance of Cyperus rotundus as an anti-androgenic, anti-bacterial, anti-cancerous, anti-convulsant, anti-diabetic, anti-diarrheal, anti-genotoxic, anti-inflammatory, anti-lipidemic, anti-malarial, anti-mutagenic, anti-obesity, anti-oxidant, anti-uropathogenic, hepato-, cardio-, neuroprotective, and nootropic agent. This paper comprises a broad review to summarize the current state of knowledge about chemical constituents, potential economic uses and therapeutic aspects of Cyperus rotundus that will aid in the development of bioethanol and modern herbal medicine through latest technologies that will promote the ability of this plant in the cure of many clinical disorders.Keywords: purple nutsedge, chemical composition, economic uses, therapeutic values, future directions
Procedia PDF Downloads 5131228 Role of Interlayer Coupling for the Power Factor of CuSbS2 and CuSbSe2
Authors: Najebah Alsaleh, Nirpendra Singh, Udo Schwingenschlogl
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The electronic and transport properties of bulk and monolayer CuSbS2 and CuSbSe2 are determined by using density functional theory and semiclassical Boltzmann transport theory, in order to investigate the role of interlayer coupling for the thermoelectric properties. The calculated band gaps of the bulk compounds are in agreement with experiments and significantly higher than those of the monolayers, which thus show lower Seebeck coefficients. Since also the electrical conductivity is lower, the monolayers are characterized by lower power factors. Therefore, interlayer coupling is found to be essential for the excellent thermoelectric response of CuSbS2 and CuSbSe2, even though it is weak.Keywords: density functional theory, thermoelectric, electronic properties, monolayer
Procedia PDF Downloads 3231227 Pomegranate Peel Based Edible Coating Treatment for Safety and Quality of Chicken Nuggets
Authors: Muhammad Sajid Arshad, Sadaf Bashir
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In this study, the effects of pomegranate peel based edible coating were determined on safety and quality of chicken nuggets. Four treatment groups were prepared as control (without coating), coating with sodium alginate (SA) (1.5%), pomegranate peel powder (PPP) (1.5%), and combination of SA and PPP. There was a significant variation observed with respect to coating treatments and storage intervals. The chicken nuggets were subjected to refrigerated storage (40C) and were analyzed at regular intervals of 0, 7, 14 1 and 21 days. The microbiological quality was determined by total aerobic and coliform counts. Total aerobic (5.09±0.05 log CFU/g) and coliforms (3.91±0.06 log CFU/g) counts were higher in uncoated chicken nuggets whereas lower was observed in coated chicken nuggets having combination of SA and PPP. Likewise, antioxidants potential of chicken nuggets was observed by assessing total phenolic contents (TPC) and DPPH activity. Higher TPC (135.66 GAE/100g) and DPPH (64.65%) were found in combination with SA and PPP, whereas minimum TPC (91.38) and DPPH (41.48) was observed in uncoated chicken nuggets. Regarding the stability analysis of chicken nuggets, thiobarbituric acid reactive substances (TBARS) and peroxide value (POV) were determined. Higher TBARS (1.62±0.03 MDA/Kg) and POV (0.92±0.03 meq peroxide/kg) were found in uncoated chicken nuggets. Hunter color values were also observed in both uncoated and coated chicken nuggets. Sensorial attributes were also observed by the trained panelists. The higher sensory score for appearance, color, taste, texture and overall acceptability were observed in control (uncoated) while in coated treatments, it was found within acceptable limits. In nutshell, the combination of SA and PPP enhanced the overall quality, antioxidant potential, and stability of chicken nuggets.Keywords: chicken nuggets, edible coatings, pomegranate peel powder, sodium alginate
Procedia PDF Downloads 1481226 Hosoya Polynomials of Mycielskian Graphs
Authors: Sanju Vaidya, Aihua Li
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Vulnerability measures and topological indices are crucial in solving various problems such as the stability of the communication networks and development of mathematical models for chemical compounds. In 1947, Harry Wiener introduced a topological index related to molecular branching. Now there are more than 100 topological indices for graphs. For example, Hosoya polynomials (also called Wiener polynomials) were introduced to derive formulas for certain vulnerability measures and topological indices for various graphs. In this paper, we will find a relation between the Hosoya polynomials of any graph and its Mycielskian graph. Additionally, using this we will compute vulnerability measures, closeness and betweenness centrality, and extended Wiener indices. It is fascinating to see how Hosoya polynomials are useful in the two diverse fields, cybersecurity and chemistry.Keywords: hosoya polynomial, mycielskian graph, graph vulnerability measure, topological index
Procedia PDF Downloads 691225 In Vitro Propagation in Barleria prionitis L. Via Callus Organogenesis
Authors: Rashmi Ranade, Neelu Joshi
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Barleria prionitis L. is a well explored Indian medicinal plant valued for its stem and leaf which forms an important ingredient of many Ayurvedic formulations. It is used for the treatment of various disorders like toothache, bleeding gums, strengthening gums, whooping cough, inflammation, arthritis, enlargement of scrotum and sciatica etc. The plant is propagated vegetatively through stem cuttings. Frequent harvesting of this plant has led to the shortage of planting material, and it has acquired the status of vulnerable plant species. Plant tissue culture technology offers a very good alternative for propagation and conservation of such plant species. The present investigation was undertaken to develop in vitro regeneration protocol for B. prionitis L. via callus organogenesis pathway. Stem and leaf explants were used for this purpose. Different media and plant growth regulators were optimized to develop the protocol. The problem of phenol secretion and browning and in vitro cultures at the establishment phase was successfully curbed with the usage of antibrowning agents such as ascorbic acid and activated charcoal. Optimum shoot multiplication was achieved by the use of liquid media and incorporation of silver nitrate and TIBA (triiodobenzoic acid) into the media. High percent rooting (76%) was observed on WPM media supplemented with IBA (2.0 mg/l), IAA (0.5 mg/l), GA3(0.5) and activated charcoal(500 mg/l). The rooted plantlets were subjected to in vitro hardening on sterile potting mix (soil:farmyard manure:compost; 1:2:1) and acclimatized under greenhouse conditions. Around 85% survival of plantlets was recorded upon acclimatization. This lab scale protocol would be tested for in vitro scaling up production of B. prionitis L.Keywords: explant browning, liquid culture, micropropagation, shoot multiplication, phenolic secretion
Procedia PDF Downloads 2841224 The Application of Raman Spectroscopy in Olive Oil Analysis
Authors: Silvia Portarena, Chiara Anselmi, Chiara Baldacchini, Enrico Brugnoli
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Extra virgin olive oil (EVOO) is a complex matrix mainly composed by fatty acid and other minor compounds, among which carotenoids are well known for their antioxidative function that is a key mechanism of protection against cancer, cardiovascular diseases, and macular degeneration in humans. EVOO composition in terms of such constituents is generally the result of a complex combination of genetic, agronomical and environmental factors. To selectively improve the quality of EVOOs, the role of each factor on its biochemical composition need to be investigated. By selecting fruits from four different cultivars similarly grown and harvested, it was demonstrated that Raman spectroscopy, combined with chemometric analysis, is able to discriminate the different cultivars, also as a function of the harvest date, based on the relative content and composition of fatty acid and carotenoids. In particular, a correct classification up to 94.4% of samples, according to the cultivar and the maturation stage, was obtained. Moreover, by using gas chromatography and high-performance liquid chromatography as reference techniques, the Raman spectral features further allowed to build models, based on partial least squares regression, that were able to predict the relative amount of the main fatty acids and the main carotenoids in EVOO, with high coefficients of determination. Besides genetic factors, climatic parameters, such as light exposition, distance from the sea, temperature, and amount of precipitations could have a strong influence on EVOO composition of both major and minor compounds. This suggests that the Raman spectra could act as a specific fingerprint for the geographical discrimination and authentication of EVOO. To understand the influence of environment on EVOO Raman spectra, samples from seven regions along the Italian coasts were selected and analyzed. In particular, it was used a dual approach combining Raman spectroscopy and isotope ratio mass spectrometry (IRMS) with principal component and linear discriminant analysis. A correct classification of 82% EVOO based on their regional geographical origin was obtained. Raman spectra were obtained by Super Labram spectrometer equipped with an Argon laser (514.5 nm wavelenght). Analyses of stable isotope content ratio were performed using an isotope ratio mass spectrometer connected to an elemental analyzer and to a pyrolysis system. These studies demonstrate that RR spectroscopy is a valuable and useful technique for the analysis of EVOO. In combination with statistical analysis, it makes possible the assessment of specific samples’ content and allows for classifying oils according to their geographical and varietal origin.Keywords: authentication, chemometrics, olive oil, raman spectroscopy
Procedia PDF Downloads 3321223 Sequential and Combinatorial Pre-Treatment Strategy of Lignocellulose for the Enhanced Enzymatic Hydrolysis of Spent Coffee Waste
Authors: Rajeev Ravindran, Amit K. Jaiswal
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Waste from the food-processing industry is produced in large amount and contains high levels of lignocellulose. Due to continuous accumulation throughout the year in large quantities, it creates a major environmental problem worldwide. The chemical composition of these wastes (up to 75% of its composition is contributed by polysaccharide) makes it inexpensive raw material for the production of value-added products such as biofuel, bio-solvents, nanocrystalline cellulose and enzymes. In order to use lignocellulose as the raw material for the microbial fermentation, the substrate is subjected to enzymatic treatment, which leads to the release of reducing sugars such as glucose and xylose. However, the inherent properties of lignocellulose such as presence of lignin, pectin, acetyl groups and the presence of crystalline cellulose contribute to recalcitrance. This leads to poor sugar yields upon enzymatic hydrolysis of lignocellulose. A pre-treatment method is generally applied before enzymatic treatment of lignocellulose that essentially removes recalcitrant components in biomass through structural breakdown. Present study is carried out to find out the best pre-treatment method for the maximum liberation of reducing sugars from spent coffee waste (SPW). SPW was subjected to a range of physical, chemical and physico-chemical pre-treatment followed by a sequential, combinatorial pre-treatment strategy is also applied on to attain maximum sugar yield by combining two or more pre-treatments. All the pre-treated samples were analysed for total reducing sugar followed by identification and quantification of individual sugar by HPLC coupled with RI detector. Besides, generation of any inhibitory compounds such furfural, hydroxymethyl furfural (HMF) which can hinder microbial growth and enzyme activity is also monitored. Results showed that ultrasound treatment (31.06 mg/L) proved to be the best pre-treatment method based on total reducing content followed by dilute acid hydrolysis (10.03 mg/L) while galactose was found to be the major monosaccharide present in the pre-treated SPW. Finally, the results obtained from the study were used to design a sequential lignocellulose pre-treatment protocol to decrease the formation of enzyme inhibitors and increase sugar yield on enzymatic hydrolysis by employing cellulase-hemicellulase consortium. Sequential, combinatorial treatment was found better in terms of total reducing yield and low content of the inhibitory compounds formation, which could be due to the fact that this mode of pre-treatment combines several mild treatment methods rather than formulating a single one. It eliminates the need for a detoxification step and potential application in the valorisation of lignocellulosic food waste.Keywords: lignocellulose, enzymatic hydrolysis, pre-treatment, ultrasound
Procedia PDF Downloads 3661222 Strong Antiferromagnetic Super Exchange in AgF2
Authors: Wojciech Grochala
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AgF2 is an important two-dimensional antiferromagnet and an analogue of [CuO2]2– sheet. However, the strength of magnetic superexchange as well as magnetic dimensionality have not been explored before . Here we report our recent Raman and neutron scattering experiments which led to better understanding of the magnetic properties of the title compound. It turns out that intra-sheet magnetic superexchange constant reaches 70 meV, thus some 2/3 of the value measured for parent compounds of oxocuprate superconductors which is over 100 meV. The ratio of intra-to-inter-sheet superexchange constants is of the order of 102 rendering AgF2 a quasi-2D material, similar to the said oxocuprates. The quantum mechanical calculations reproduce the abovementioned values quite well and they point out to substantial covalence of the Ag–F bonding. After 3 decades of intense research on layered oxocuprates, AgF2 now stands as a second-to-none analogue of these fascinating systems. It remains to be seen whether this 012 parent compound may be doped in order to achieve superconductivity.Keywords: antiferromagnets, superexchange, silver, fluorine
Procedia PDF Downloads 1291221 A Spectrophotometric Method for the Determination of Folic Acid - A Vitamin B9 in Pharmaceutical Dosage Samples
Authors: Chand Pasha, Yasser Turki Alharbi, Krasamira Stancheva
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A simple spectrophotometric method for the determination of folic acid in pharmaceutical dosage samples was developed. The method is based on the diazotization reaction of thiourea with sodium nitrite in acidic medium yields diazonium compounds, which is then coupled with folic acid in basic medium yields yellow coloured azo dyes. Beer’s Lamberts law is observed in the range 0.5 – 16.2 μgmL-1 at a maximum wavelength of 416nm. The molar absorbtivity, sandells sensitivity, linear regression equation and detection limit and quantitation limit were found to be 5.695×104 L mol-1cm-1, 7.752×10-3 g cm-2, y= 0.092x - 0.018, 0.687 g mL-1 and 2.083 g mL-1. This method successfully determined Folate in Pharmaceutical formulations.Keywords: folic acid determination, spectrophotometry, diazotization, thiourea, pharmaceutical dosage samples
Procedia PDF Downloads 761220 Ultrasound Assisted Alkaline Potassium Permanganate Pre-Treatment of Spent Coffee Waste
Authors: Rajeev Ravindran, Amit K. Jaiswal
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Lignocellulose is the largest reservoir of inexpensive, renewable source of carbon. It is composed of lignin, cellulose and hemicellulose. Cellulose and hemicellulose is composed of reducing sugars glucose, xylose and several other monosaccharides which can be metabolised by microorganisms to produce several value added products such as biofuels, enzymes, aminoacids etc. Enzymatic treatment of lignocellulose leads to the release of monosaccharides such as glucose and xylose. However, factors such as the presence of lignin, crystalline cellulose, acetyl groups, pectin etc. contributes to recalcitrance restricting the effective enzymatic hydrolysis of cellulose and hemicellulose. In order to overcome these problems, pre-treatment of lignocellulose is generally carried out which essentially facilitate better degradation of lignocellulose. A range of pre-treatment strategy is commonly employed based on its mode of action viz. physical, chemical, biological and physico-chemical. However, existing pretreatment strategies result in lower sugar yield and formation of inhibitory compounds. In order to overcome these problems, we proposes a novel pre-treatment, which utilises the superior oxidising capacity of alkaline potassium permanganate assisted by ultra-sonication to break the covalent bonds in spent coffee waste to remove recalcitrant compounds such as lignin. The pre-treatment was conducted for 30 minutes using 2% (w/v) potassium permanganate at room temperature with solid to liquid ratio of 1:10. The pre-treated spent coffee waste (SCW) was subjected to enzymatic hydrolysis using enzymes cellulase and hemicellulase. Shake flask experiments were conducted with a working volume of 50mL buffer containing 1% substrate. The results showed that the novel pre-treatment strategy yielded 7 g/L of reducing sugar as compared to 3.71 g/L obtained from biomass that had undergone dilute acid hydrolysis after 24 hours. From the results obtained it is fairly certain that ultrasonication assists the oxidation of recalcitrant components in lignocellulose by potassium permanganate. Enzyme hydrolysis studies suggest that ultrasound assisted alkaline potassium permanganate pre-treatment is far superior over treatment by dilute acid. Furthermore, SEM, XRD and FTIR were carried out to analyse the effect of the new pre-treatment strategy on structure and crystallinity of pre-treated spent coffee wastes. This novel one-step pre-treatment strategy was implemented under mild conditions and exhibited high efficiency in the enzymatic hydrolysis of spent coffee waste. Further study and scale up is in progress in order to realise future industrial applications.Keywords: spent coffee waste, alkaline potassium permanganate, ultra-sonication, physical characterisation
Procedia PDF Downloads 3571219 Carbon Nanocomposites : Structure, Characterization and Environmental Application
Authors: Bensacia Nabila, Hadj-Ziane Amel, Sefah Karima
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Carbon nanocomposites have received more attention in the last years in view of their special properties such as low density, high specific surface area, and thermal and mechanical stability. Taking into account the importance of these materials, many studies aimed at improving the synthesis process have been conducted. However, the presence of impurities could affect significantly the properties of these materials, and the characterization of these compounds is an important challenge to assure the quality of the new carbon nanocomposites. The present study aims to develop a new recyclable decontaminating material for dyes removal. This new material consists of an active element based on carbon nanotubes wrapped in a microcapsule of iron oxide. The adsorbent is characterized by Transmission electron microscopy, X-ray diffraction and the surface area was measured by the BET method.Keywords: carbon nanocomposite, chitozen, elimination, dyes
Procedia PDF Downloads 3211218 Problems and Solutions in the Application of ICP-MS for Analysis of Trace Elements in Various Samples
Authors: Béla Kovács, Éva Bódi, Farzaneh Garousi, Szilvia Várallyay, Áron Soós, Xénia Vágó, Dávid Andrási
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In agriculture for analysis of elements in different food and food raw materials, moreover environmental samples generally flame atomic absorption spectrometers (FAAS), graphite furnace atomic absorption spectrometers (GF-AAS), inductively coupled plasma optical emission spectrometers (ICP-OES) and inductively coupled plasma mass spectrometers (ICP-MS) are routinely applied. An inductively coupled plasma mass spectrometer (ICP-MS) is capable for analysis of 70-80 elements in multielemental mode, from 1-5 cm3 volume of a sample, moreover the detection limits of elements are in µg/kg-ng/kg (ppb-ppt) concentration range. All the analytical instruments have different physical and chemical interfering effects analysing the above types of samples. The smaller the concentration of an analyte and the larger the concentration of the matrix the larger the interfering effects. Nowadays there is very important to analyse growingly smaller concentrations of elements. From the above analytical instruments generally the inductively coupled plasma mass spectrometer is capable of analysing the smallest concentration of elements. The applied ICP-MS instrument has Collision Cell Technology (CCT) also. Using CCT mode certain elements have better (smaller) detection limits with 1-3 magnitudes comparing to a normal ICP-MS analytical method. The CCT mode has better detection limits mainly for analysis of selenium, arsenic, germanium, vanadium and chromium. To elaborate an analytical method for trace elements with an inductively coupled plasma mass spectrometer the most important interfering effects (problems) were evaluated: 1) Physical interferences; 2) Spectral interferences (elemental and molecular isobaric); 3) Effect of easily ionisable elements; 4) Memory interferences. Analysing food and food raw materials, moreover environmental samples an other (new) interfering effect emerged in ICP-MS, namely the effect of various matrixes having different evaporation and nebulization effectiveness, moreover having different quantity of carbon content of food and food raw materials, moreover environmental samples. In our research work the effect of different water-soluble compounds furthermore the effect of various quantity of carbon content (as sample matrix) were examined on changes of intensity of the applied elements. So finally we could find “opportunities” to decrease or eliminate the error of the analyses of applied elements (Cr, Co, Ni, Cu, Zn, Ge, As, Se, Mo, Cd, Sn, Sb, Te, Hg, Pb, Bi). To analyse these elements in the above samples, the most appropriate inductively coupled plasma mass spectrometer is a quadrupole instrument applying a collision cell technique (CCT). The extent of interfering effect of carbon content depends on the type of compounds. The carbon content significantly affects the measured concentration (intensities) of the above elements, which can be corrected using different internal standards.Keywords: elements, environmental and food samples, ICP-MS, interference effects
Procedia PDF Downloads 5041217 Preservation of Historical Zelkova carpinifolia Wooden Structure in Humid Weather
Authors: A. Mahshid Kakouei, B. Kumaran Suberamanin, C. Sabzali Musa Kahn, D. Mina Kakouei
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This study aims to identify suitable conservative product for the conservation and restoration of historical Zelkova Carpinifolia wood located in humid weather. The superficial properties and hardness of 14 compounds treated with several consolidants were compared. The consolidants have been applied alone, with synthetic resin or with protein glues and natural resins by the brushing method. Colorimetric measurements, observation methods and hardness tests were conducted before and after aging to verify the possible changes of the treated wood and the consolidating resistance. The compound 1:2 of Butvar B98 and sandarac in 5% ethanol was found to be more effective, providing a suitable compound compared to the other consolidants tested.Keywords: Zelkova carpinifolia, consolidation, synthetic resin, penetration depth, hardness
Procedia PDF Downloads 3571216 Synthesis of Some 1h-Benzimidazoles as Inhibitors of EGFR Tyrosine Kinase
Authors: İsmail Çeli̇k, Gülgün Ayhan-Kılcıgi̇l, Arzu Onay-Beşi̇kçi̇
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In this study, some 2-(2-phenyl/substitutedphenyl)- lH-benzo[d]'imidazol-l-yl)-N'-(alkylthiosemicarbazide were designed and prepared. Firstly, 2-phenyl/ suhstitutedphenyl-lH-Benzo[d]imidazole was prepared via oxidative condensation of o-phenylenediamine, benzaldehyde and sodium metabisulfite. Treatment of the benzimidazole compound with ethyl chloroacetate in KOH/DMSO gave the ester compound ethyl 2-(2-substitutedphenyl)-1H-benzo[d]imidazol-l-yl)acetate. Hydrazine hydrate and the ester in ethanol were refluxed for 4 h to give 2-(2-phenyl/substitutedphenyl)-1H-benzo[d]imidazol-l-yl)acetohydrazide. Thiosemicarbazides were obtained by condensing acyl hydrazide with the alkylisothiocyanate in ethanol. Following the structure elucidation, benzimidazole compounds were tested for their EGFR kinase inhibitory activities by using ADP-GloTM Kinase Assay.Keywords: benzimidazole, EGFR kinase inhibitor, synthesis, thiosemicarbazide
Procedia PDF Downloads 2571215 Biological Activity of Essential Oils from Salvia nemorosa L.
Authors: Abdol-Hassan Doulah
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In this study, antimicrobial activity of essential oil and ethyl acetate and ether extracts of S. nemorosa were examined against some species of bacteria and fungi. The essential oil of the aerial part of S. nemorosa was examined by GC and GC-MS. In the essential oil of S. nemorosa 26 Compounds have been identified. 2-Nonanone (44.09 %), 2-Undecanone (33.79 %), E-Caryophyllene (3.74 %) and 2-Decanone (2.89 %) were the main components of the essential oil. The essential oil analysis showed greatest antimicrobial activity against Staphylococcus epidermidis (5.3 μg/ml) and S. cerevisiae (9.3 μg/ml). The ethyl acetate showed greatest antimicrobial activity against Bacillus subtilis (106.7 μg/ml), Candida albicans (5.3 μg/ml) and ether extract showed greatest antimicrobial activity against Klebseilla pneumoniae (10.7 μg/ml) and Saccharomyces cerevisiae (10.7 μg/ml). In conclusion, we suggest that the antimicrobial activity of S. nemorosa may be due to its content of germacrene and linalool.Keywords: antibacterial activity, antifungal activity, Salvia nemorosa L., essential oils, biological activity
Procedia PDF Downloads 4931214 Acute Myocardial Infarction Associated with Ingestion of Herbal Mixtures Containing Acetylcholinesterase Inhibitors: A Case Study
Authors: M. Hakami, A. Jammaly, I. Attafi, M. Oraiby, M. Jeraiby
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We reviewed an unusual case of a 65-year-old male taking an herbal mixture containing compounds with anticholinesterase activity for a long period of time, presented with acute my myocardial infarction and multiple organ dysfunction syndrome followed by death. Clinically, there are findings correlated with anticholinesterase activity, such as bilateral miosis, diaphoresis, vomiting and fasciculation without a history of any toxic ingestion or exposure. Gas chromatography–mass spectrometry screening studies identified the presence of thymol, anethole in the herbal extract and butylated hydroxytoluene in the blood sample. Hence, with this case report, we intend to highlight the necessity of evaluating the long-term use of the herbal mixture.Keywords: cholinesterase inhibitors, thymole, anethole, butylatedhydroxytoluene, cardiac toxicity, myocardial infarction
Procedia PDF Downloads 2791213 Bismuth-Inhibitory Effects on Bacteria and Stimulation of Fungal Growth In vitro
Authors: Sulaiman B. Ali Alharbi, Bassam H. Mashat, Naif Abdullah Al-Harbi, Milton Wainwright, Abeer S. Aloufi, Sulamain Alnaimat
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Bismuth salicylate was found to inhibit the growth of a range of bacteria and yeast, Candida albican. In general the growth of bacteria did not result in the increase in bismuth solubilisation, in contrast, bismuth solubilisation increased following the growth of C. albicans. A significant increase in the biomass (dry weight) of Aspergillus niger and Aspergillus oryzae occurred in vitro when these fungi were grown in the presence of bismuth salicylate. Biomass increase occurred over a range of bismuth compound additions, which in the case of A. oryzae was associated with the increase in the solubilisation of the insoluble bismuth compounds.Keywords: bacterial inhibition, fungal growth stimulation, medical uses of bismuth, yeast inhibition
Procedia PDF Downloads 3411212 Examining Microbial Decomposition, Carbon Cycling and Storage in Cefni Coastal Salt Marsh, Anglesey Island, Wales, United Kingdom
Authors: Dasat G. S., Christopher F. Tim, J. Dun C.
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Salt marshes are known to sequester carbon dioxide from the atmosphere into the soil, but natural and anthropogenic activities could trigger the release of large quantities of centuries of buried carbon dioxide, methane and nitrous oxide (CO2, CH4 and N2O) which are the major greenhouse gases (GHGs) implicated with climate change. Therefore, this study investigated the biogeochemical activities by collecting soil samples from low, mid and high zones of the Cefni salt marsh, within the Maltreat estuary, on the island of Anglesey, north Wales, United Kingdom for a consortium of laboratory based experiments using standard operating protocols (POS) to quantify the soil organic matter contents and the rate of microbial decomposition and carbon storage at the Carbon Capture Laboratory of Bangor University Wales. Results of investigations reveals that the mid zone had 56.23% and 9.98% of soil water and soil organic matter (SOM) contents respectively higher than the low and high zones. Phenol oxidase activity (1193.53µmol dicq g-1 h-1) was highest at the low zone in comparison to the high and mid zones (867.60 and 608.74 µmol dicq g-1 h-1) respectively. Soil phenolic concentration was found to be highest in the mid zone (53.25 µg-1 g-1) when compared with those from the high (15.66 µg-1 g-1) and low (4.18 µg-1 g-1) zones respectively. Activities of hydrolase enzymes showed similar trend for the high and low zones and much lower activities in the mid zone. CO2 flux from the mid zone (6.79 ug g-1 h-1) was significantly greater than those from high (-2.29 ug g-1 h-1) and low (1.30 µg g-1 h-1) zones. Since salt marshes provide essential ecosystem services, their degradation or alteration in whatever form could compromise such ecosystem services and could convert them from net sinks into net sources with consequential effects to the global environment.Keywords: saltmarsh, decomposition, carbon cycling, enzymes
Procedia PDF Downloads 821211 Separation of Some Pyrethroid Insecticides by High-Performance Liquid Chromatography
Authors: Fairouz Tazerouti, Samira Ihadadene
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Pyrethroids are synthetic pesticides that originated from the modification of natural pyrethrins to improve their biological activity and stability. They are a family of chiral pesticides with a large number of stereoisomers. Enantiomers of synthetic pyretroids present different insecticidal activity, toxicity against aquatic invertebrates and persistence in the environment so the development of rapid and sensitive chiral methods for the determination of different enantiomers is necessary. In this study, the separation of enantiomers of pyrethroid insecticides has been systematically studied using three commercially chiral high-performance liquid chromatography columns. Useful resolution was obtained for compounds with a variety of acid and alcohol moieties, and containing one to four chiral centres. The chromatographic behaviour of the diastereomers of some of these insecticides by using normal, polar and reversed mobile phase mode were also examined.Keywords: pesticides, analysis, liquid chromatography, pyrethroids
Procedia PDF Downloads 3771210 Eucalyptus camaldulensis Leaves Attacked by the Gall Wasp Leptocybe invasa: A Phyto-Volatile Constituents Study
Authors: Maged El-Sayed Mohamed
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Eucalyptus camaldulensis is one on the most well-known species of the genus Eucalyptus in the Middle east, its importance relay on the high production of its unique volatile constituents which exhibits many medicinal and pharmacological activities. The gall-forming wasp (Leptocybe invasa) has recently come into sight as the main pest attacking E. camaldulensis and causing severe injury. The wasp lays its eggs in the petiole and midrib of leaves and stems of young shoots of E. camaldulensis, which leads to gall formation. Gall formation by L. invasa damages growing shoot and leaves of Eucalyptus, resulting in abscission of leaves and drying. AIM: This study is an attempt to investigate the effect of the gall wasp (Leptocybe invasa) attack on the volatile constitutes of E. camaldulensis. This could help in the control of this wasp through stimulating plant defenses or production of a new allelochemicals or insecticide. The study of volatile constitutes of Eucalyptus before and after attack by the wasp can help the re-use and recycle of the infected Eucalyptus trees for new pharmacological and medicinal activities. Methodology: The fresh gall wasp-attacked and healthy leaves (100 g each) were cut and immediately subjected to hydrodistillation using Clevenger-type apparatus for 3 hours. The volatile fractions isolated were analyzed using Gas chromatography/mass spectrometry (GC/MS). Kovat’s retention indices (RI) were calculated with respect to a set of co-injected standard hydrocarbons (C10-C28). Compounds were identified by comparing their spectral data and retention indices with Wiley Registry of Mass Spectral Data 10th edition (April 2013), NIST 11 Mass Spectral Library (NIST11/2011/EPA/NIH) and literature data. Results: Fifty-nine components representing 89.13 and 88.60% of the total volatile fraction content respectively were quantitatively analyzed. Twenty-six major compounds at an average concentration greater than 0.1 ± 0.02% have been used for the statistical comparison. From those major components, twenty-one were found in both the attacked and healthy Eucalyptus leaves’ fractions in different concentration and five components, mono terpene p-Mentha-2-4(8) diene and the sesquiterpenes δ-elemene, β-elemene, E-caryophyllene and Bicyclogermacrene, were unique and only produced in the attacked-leaves’ fraction. CONCLUSION: Newly produced components or those commonly found in the volatile fraction and changed in concentration could represent a part of the plant defense mechanisms or might be an element of the plant allelopathic and communication mechanisms. Identification of the components of the gall wasp-damaged leaves can help in their recycling for different physiological, pharmacological and medicinal uses.Keywords: Eucalyptus camaldulensis, eucalyptus recycling, gall wasp, Leptocybe invasa, plant defense mechanisms, Terpene fraction
Procedia PDF Downloads 3581209 Antibacterial and Antioxidant Capacity of Fabric Treated with Purple-Fleshed Sweet Potato Extract
Authors: Kyung Hwa Hong, Eunmi Koh
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Wool and cotton fabrics are pretreated by a tannic acid aqueous solution to increase their dyeability and then dyed by Purple-Fleshed Sweet Potato (PSP) extract. The dyed fabrics are then investigated by various analysis techniques. The results revealed that wool and cotton fabrics can be dyed bluish red through the pretreatment and dyeing process. Both wool and cotton fabrics only pretreated with tannic acid display decreased L* value but no significant changes in a* and b* values as the concentration of tannic acid increases. And, as expected, the pretreated fabrics are even darker and show a richer purple color after the dyeing process with the PSP extract. With regard to the colorfastness of wool and cotton fabrics dyed by PSP extract in cleaning circumstances, such as dry-cleaning (for wool) and washing (for cotton), the wool and cotton fabrics had a 4.0 and 4.0 grade of colorfastness to dry-cleaning and washing, respectively. However, they both exhibited significantly inferior colorfastness to light (grade of 1.5). Thus, it was found that there is still a need for improvement with regard to color fastness, particularly against light. On the other hand, the wool and cotton fabrics also showed antibacterial and antioxidant characteristics. In addition, both the wool and cotton fabrics showed potential antibacterial ability (>99%) against Staphylococcus aureus; however, they showed somewhat insufficient antibacterial ability (60.8% for wool and 94.8% for cotton) against Klebsiella pneumoniae. Also, their antioxidant abilities increased up to ca. 90% with an increase in the tannic acid concentration (up to 0.5%). However, after the dyeing process, the antibacterial and antioxidant ability tended to decrease. This is assumed to have occurred because functional moieties such as phenolic acids were detached from the pretreated fabrics into the hot water (the dyeing solution) during the dyeing process. Therefore, further study would be necessary to derive the optimum treatment and dyeing conditions so as to maximize the coloring effect and functionalities of the fabrics.Keywords: antibacterial activity, antioxidant activity, purple-fleshed sweet potato, fabrics
Procedia PDF Downloads 2921208 Possibility of Membrane Filtration to Treatment of Effluent from Digestate
Authors: Marcin Debowski, Marcin Zielinski, Magdalena Zielinska, Paulina Rusanowska
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The problem with digestate management is one of the most important factors influencing on the development and operation of biogas plant. Turbidity and bacterial contamination negatively affect the growth of algae, which can limit the use of the effluent in the production of algae biomass on a large scale. These problems can be overcome by cultivating of algae species resistant to environmental factors, such as Chlorella sp., Scenedesmus sp., or reducing load of organic compounds to prevent bacterial contamination. The effluent requires dilution and/or purification. One of the methods of effluent treatment is the use of a membrane technology such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO), depending on the membrane pore size and the cut off point. Membranes are a physical barrier to solids and particles larger than the size of the pores. MF membranes have the largest pores and are used to remove turbidity, suspensions, bacteria and some viruses. UF membranes remove also color, odor and organic compounds with high molecular weight. In treatment of wastewater or other waste streams, MF and UF can provide a sufficient degree of purification. NF membranes are used to remove natural organic matter from waters, water disinfection products and sulfates. RO membranes are applied to remove monovalent ions such as Na⁺ or K⁺. The effluent was used in UF for medium to cultivation of two microalgae: Chlorella sp. and Phaeodactylum tricornutum. Growth rates of Chlorella sp. and P. tricornutum were similar: 0.216 d⁻¹ and 0.200 d⁻¹ (Chlorella sp.); 0.128 d⁻¹ and 0.126 d⁻¹ (P. tricornutum), on synthetic medium and permeate from UF, respectively. The final biomass composition was also similar, regardless of the medium. Removal of nitrogen was 92% and 71% by Chlorella sp. and P. tricornutum, respectively. The fermentation effluents after UF and dilution were also used for cultivation of algae Scenedesmus sp. that is resistant to environmental conditions. The authors recommended the development of biorafinery based on the production of algae for the biogas production. There are examples of using a multi-stage membrane system to purify the liquid fraction from digestate. After the initial UF, RO is used to remove ammonium nitrogen and COD. To obtain a permeate with a concentration of ammonium nitrogen allowing to discharge it into the environment, it was necessary to apply three-stage RO. The composition of the permeate after two-stage RO was: COD 50–60 mg/dm³, dry solids 0 mg/dm³, ammonium nitrogen 300–320 mg/dm³, total nitrogen 320–340 mg/dm³, total phosphorus 53 mg/dm³. However compostion of permeate after three-stage RO was: COD < 5 mg/dm³, dry solids 0 mg/dm³, ammonium nitrogen 0 mg/dm³, total nitrogen 3.5 mg/dm³, total phosphorus < 0,05 mg/dm³. Last stage of RO might be replaced by ion exchange process. The negative aspect of membrane filtration systems is the fact that the permeate is about 50% of the introduced volume, the remainder is the retentate. The management of a retentate might involve recirculation to a biogas plant.Keywords: digestate, membrane filtration, microalgae cultivation, Chlorella sp.
Procedia PDF Downloads 3521207 Cholinesterase Inhibitory Indole Alkaloids from the Bark of Rauvolfia reflexa
Authors: Mehran Fadaeinasab, Alireza Basiri, Yalda Kia, Hamed Karimian, Hapipah Mohd Ali, Vikneswaran Murugaiyah
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Two new, rauvolfine C and 3- methyl-10,11-dimethoxyl-6- methoxycarbonyl- β- carboline, along with five known indole alkaloids, macusine B, vinorine, undulifoline, isoresrpiline and rescinnamine were isolated from the bark of Rauvolfia reflexa. All the compounds showed good to moderate cholinesterase inhibitory activity with IC50 values in the range of 8.06 to 73.23 πM, except rauvolfine C that was inactive against acetylcholinesterase (AChE). Rescinnamine, a dual inhibitor was found to be the most potent inhibitor among the isolated alkaloids against both AChE and butyrylcholinesterase (BChE). Molecular docking revealed that rescinnamine interacted differently on AChE and BChE, by means of hydrophobic interactions and hydrogen bonding.Keywords: Rauvolfia reflexa, indole alkaloids, acetylcholinesterase, butyrylcholinesterase, molecular docking
Procedia PDF Downloads 5921206 Climate Change and Poverty Nexus
Authors: O. Babalola Oladapo, A. Igbatayo Samuel
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Climate change and poverty are global issues which cannot be waved aside in welfare of the ever increasing population. The causes / consequences are far more elaborate in developing countries, including Nigeria, which poses threats to the existence of man and his environment. The dominant role of agriculture makes it obvious that even minor climate deteriorations can cause devastating socio-economic consequences. Policies to curb the climate change by reducing the consumption of fossil fuels like oil, gas or carbon compounds have significant economical impacts on the producers/suppliers of these fuels. Thus a unified political narrative that advances both agendas is needed, because their components of an environmental coin that needs to be addressed. The developed world should maintain a low-carbon growth & real commitment of 0.7% of gross national income, as aid to developing countries & renewable energy approach should be emphasized, hence global poverty combated.Keywords: climate change, greenhouse gases, Nigeria, poverty
Procedia PDF Downloads 3741205 Development of High-Efficiency Down-Conversion Fluoride Phosphors to Increase the Efficiency of Solar Panels
Authors: S. V. Kuznetsov, M. N. Mayakova, V. Yu. Proydakova, V. V. Pavlov, A. S. Nizamutdinov, O. A. Morozov, V. V. Voronov, P. P. Fedorov
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Increase in the share of electricity received by conversion of solar energy results in the reduction of the industrial impact on the environment from the use of the hydrocarbon energy sources. One way to increase said share is to improve the efficiency of solar energy conversion in silicon-based solar panels. Such efficiency increase can be achieved by transferring energy from sunlight-insensitive areas of work of silicon solar panels to the area of their photoresistivity. To achieve this goal, a transition to new luminescent materials with the high quantum yield of luminescence is necessary. Improvement in the quantum yield can be achieved by quantum cutting, which allows obtaining a quantum yield of down conversion of more than 150% due to the splitting of high-energy photons of the UV spectral range into lower-energy photons of the visible and near infrared spectral ranges. The goal of present work is to test approach of excitation through sensibilization of 4f-4f fluorescence of Yb3+ by various RE ions absorbing in UV and Vis spectral ranges. One of promising materials for quantum cutting luminophores are fluorides. In our investigation we have developed synthesis of nano- and submicron powders of calcium fluoride and strontium doped with rare-earth elements (Yb: Ce, Yb: Pr, Yb: Eu) of controlled dimensions and shape by co-precipitation from water solution technique. We have used Ca(NO3)2*4H2O, Sr(NO3)2, HF, NH4F as precursors. After initial solutions of nitrates were prepared they have been mixed with fluorine containing solution by dropwise manner. According to XRD data, the synthesis resulted in single phase samples with fluorite structure. By means of SEM measurements, we have confirmed spherical morphology and have determined sizes of particles (50-100 nm after synthesis and 150-300 nm after calcination). Temperature of calcination appeared to be 600°C. We have investigated the spectral-kinetic characteristics of above mentioned compounds. Here the diffuse reflection and laser induced fluorescence spectra of Yb3+ ions excited at around 4f-4f and 4f-5d transitions of Pr3+, Eu3+ and Ce3+ ions in the synthesized powders are reported. The investigation of down conversion luminescence capability of synthesized compounds included measurements of fluorescence decays and quantum yield of 2F5/2-2F7/2 fluorescence of Yb3+ ions as function of Yb3+ and sensitizer contents. An optimal chemical composition of CaF2-YbF3- LnF3 (Ln=Ce, Eu, Pr), SrF2-YbF3-LnF3 (Ln=Ce, Eu, Pr) micro- and nano- powders according to criteria of maximal IR fluorescence yield is proposed. We suppose that investigated materials are prospective in solar panels improvement applications. Work was supported by Russian Science Foundation grant #17-73- 20352.Keywords: solar cell, fluorides, down-conversion luminescence, maximum quantum yield
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