Search results for: disodium hydrogen phosphate

Authors: Olusegun D. Omotoso

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The use of Moringa oleifera seed oil in the prevention and cure of many ailments particularly, neurodegenerative diseases have been on increasing trend in Nigeria. The study was aimed at investigating the ameliorative or reversal effects by the intervention of Moringa oleifera seed oil on the damage to frontal cortex of Wistar rats by cadmium. Twenty-eight Wistar rats of both sexes weighed between 73g-151g were used. The animals were acclimatized and were fed on rat chow and water ad libitum. The rats were randomly divided into four groups A, B, C and D of 7 rats each. Group A served as control which received 2.5mg/kgbw phosphate buffer intra-peritoneally, while group D served as Moringa-treated control and received oral administration of 2.0 mg/kgbw Moringa oleifera oil. Groups B and C were injected intra-peritoneally with 3.5mg/kgbw CdSO₄.8H₂O single dose. Group C received orally administration of 2.0mg/kgbw Moringa oleifera oil. The intervention lasted for four weeks after which the animals were sacrificed by cervical dislocation and the tissues processed histologically. The immuno-histoarchitecture of the frontal cortex was characterized by pyknosis of nuclei as well as activation of astrocytes which was evidence in group B rats, while those animals in group C showed ameliorative effect that were evidence in reduction in the number of pyknotic nuclei and reduction of activated astrocytes as compared with control group A and Moringa-treated group D. It can be deduced that Moringa oleifera seed oil has natural antioxidant constituents that might have ameliorated the immuno-histoarchitectural damage caused by cadmium.

Keywords: cadmium, immuno-histoarchitecture, Moringa oleifera, pyknotic nuclei

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Authors: Md. Hasan Zahir

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Y2O3-doped silica membranes were synthesized with the sol-gel method by using a tetraethyl orthosilicate-derived sol mixed with yttrium nitrate hexahydrate. These solutions were used to fabricate hydrogen separation microporous membranes with a sandwich-type structure on γ-Al2O3 supported by tubular α-Al2O3. Pore size distribution measurements were conducted directly on the membranes before and after hydrothermal treatment with a nano-permporometer. The gas permeance properties of the membranes were measured in the temperature range 100–500°C. The Y-doped SiO2 membrane (Si/Y = 3/1) was found to exhibit asymptotically stable permeances of 2.39×10-7 mol m-2 s -1 Pa-1 for He and 6.19 ×10-10 mol m-2 s -1 Pa-1 for CO2, with a high selectivity of 386 (He/CO2) at 500°C for 20 h in the presence of steam. The Y-doped silica membranes exhibit very high gas permeances for molecules with smaller kinetic diameters. The apparent activation energies of the H2 permeance at 400°C were 24.2±0.2 and 21.3±0.7 kJ mol−1 for SiO2 and Si/Y, respectively. Very high permeances were obtained for N2 and O2, 2.2 and 5 × 10-8 mol m-2 s -1 Pa-1 respectively, which demonstrates that these materials are promising air purification and/or separation systems that block larger impurity molecules by molecular sieving effects. Y-doped SiO2 exhibits greater hydrothermal stability at high temperatures and higher selectivity than SiO2 membranes.

Keywords: ceramic membrane, gas separation, hydrothermal stability, rare earth doped-Silica

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Authors: Gyati Shilakari Asthana, Abhay Asthana

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Purpose: The therapeutic potential of oligonucleotide (ODN) is primarily dependent upon its safe and efficient delivery to specific cells overcoming degradation and maximizing cellular uptake in vivo. The present study is focused to design low molecular weight chitosan nanoconstructs to meet the requirements of safe and effectual delivery of ODNs. LMW-chitosan is a biodegradable, water soluble, biocompatible polymer and is useful as a non-viral vector for gene delivery due to its better stability in water. Methods: LMW chitosan ODN nanoparticles (CHODN NPs) were formulated by self assembled method using various N/P ratios (moles ratio of amine groups of CH to phosphate moieties of ODNs; 0.5:1, 1:1, 3:1, 5:1 and 7:1) of CH to ODN. The developed CHODN NPs were evaluated with respect to gel retardation assay, particle size, zeta potential and cytotoxicity and transfection efficiency. Results: Complete complexation of CH/ODN was achieved at the charge ratio of 0.5:1 or above and CHODN NPs displayed resistance against DNase I. On increasing the N/P ratio of CH/ODN, particle size of the NPs decreased whereas zeta potential (ZV) value increased. No significant toxicity was observed at all CH concentrations. The transfection efficiency was increased on increasing N/P ratio from 1:1 to 3:1, whereas it was decreased with further increment in N/P ratio upto 7:1. Maximum transfection of CHODN NPs with both the cell lines (Raw 267.4 cells and Hela cells) was achieved at N/P ratio of 3:1. The results suggest that transfection efficiency of CHODN NPs is dependent on N/P ratio. Conclusion: Thus the present study states that LMW chitosan nanoparticulate carriers would be acceptable choice to improve transfection efficiency in vitro as well as in vivo delivery of oligonucleotide.

Keywords: LMW-chitosan, chitosan nanoparticles, biocompatibility, cytotoxicity study, transfection efficiency, oligonucleotide

Procedia PDF Downloads 477

Authors: Shekher Kummari, V. Sunil Kumar, K. Vengatajalabathy Gobi

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A simple, cost-effective, reusable and reagent-free electrochemical biosensor is developed with functionalized multiwall carbon nanotube paste electrode (f-CNTPE) for the sensitive and selective determination of the important chemotherapeutic drug methotrexate (MTX), which is widely used for the treatment of various cancer and autoimmune diseases. The electrochemical response of the fabricated electrode towards the detection of MTX is examined by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). CV studies have shown that f-CNTPE electrode system exhibited an excellent electrocatalytic activity towards the oxidation of MTX in phosphate buffer (0.2 M) compared with a conventional carbon paste electrode (CPE). The oxidation peak current is enhanced by nearly two times in magnitude. Applying the DPV method under optimized conditions, a linear calibration plot is achieved over a wide range of concentration from 4.0×10⁻⁷ M to 5.5×10⁻⁶ M with the detection limit 1.6×10⁻⁷ M. further, by applying the SWV method a parabolic calibration plot was achieved starting from a very low concentration of 1.0×10⁻⁸ M, and the sensor could detect as low as 2.9×10⁻⁹ M MTX in 10 s and 10 nM were detected in steady state current-time analysis. The f-CNTPE shows very good selectivity towards the specific recognition of MTX in the presence of important biological interference. The electrochemical biosensor detects MTX in-vitro directly from pharmaceutical sample, undiluted urine and human blood serum samples at a concentration range 5.0×10⁻⁷ M with good recovery limits.

Keywords: amperometry, electrochemical detection, human blood serum, methotrexate, MWCNT, SWV

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Authors: Mohammedi Ferhate, Hakim Chadli, Laggoun Chaouki

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The main objectives of work in this area are, first, obtaining the high laser energies in short time durations needed for the feasibility studies of laser induced thermodynamically exothermic chemical reactions , second, investigating the physical principles that can be used to make laser sources capable of delivering high average powers. We note that, in order to reach both objectives, one has to convert electrical or chemical energy into laser energy, using dense gaseous media.. We present results from the early development of an F atom source appropriate for HF and DF chemical laser research. We next explain the very important difficulties encountered in working with dense gases for that purpose, and we shall describe how, especially at Evaluation of downstream-mixing scheme –levels transitions (001) → (100) and (001) → (020) gas dynamic laser The physical phenomena that control the operation of presently existing laser devices are now sufficiently well understood, so that it is possible to predict that new generations of lasers could be designed in the future. The proposed model of excitation and relaxation levels was finally proved by the computational numerical code of Matlab toolboxes of different parameters of nozzle.

Keywords: hydrogen, combust, chemical laser, halogen atom

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Authors: Milda A. Cruz-Huaranga, Natalí Carbo-Bustinza, Javier Linkolk López-Gonzales, K. Depaz, Gina M. Tito T., Soledad Torres-Calderón

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The objective of this study was to improve water quality in the “La Mansión” pond in order to irrigate green spaces on the Peruvian Union University campus (Lima, Peru) using the aquatic species Eichhornia Crassipes. Furthermore, tree trimming and cleaning activities were performed that reduced water pollution caused by organic deposits and feathers from wild birds. The impaired waterbody is located on the campus of the Peruvian Union University, 580 meters above sea level, with a volume of 6,405.336 m3, an area of 3,050.16 m2, 256.81 m perimeter, and 0.12 m3/s input flow. Seven 1.8 m2 floating systems were implemented, with 12 common water hyacinth plants in each system. Before implementing this system, a water quality analysis was performed to analyse the physical-chemical, microbiological, and organoleptic parameters. The pre-analysis revealed the pond’s critical condition, with electrical conductivity: 556 mg/l; phosphate: < 0.5; pH: 7.06; total solids: 412 mg/l; arsenic: <0.01; lead: 0.115; BOD5: 14; COD: 16.94; dissolved oxygen: 13; total coliforms: 24000 MCL/100 ml; and thermo-tolerant coliforms: 11000 MCL/100 ml. After implementing the system, the following results were obtained: EC: 495 mg/l; DO:9.2 mg/l; TS: 235 mg/l; BOD5: 7.7; COD: 8.47; Pb: 0.001 mg/l; TC: 460 MCL/100 ml; FC: 240 MCL/100 ml. Thus, we confirmed that the system is 78.79% efficient regarding the Peruvian ECA (Environmental Quality Standards) established for water according to DS #015-2015-MINAM. Therefore, the water is suitable for plant irrigation. Finally, we concluded that treating wastewater with the species Eichhornia Crassipes is efficient since an improvement was achieved in the impaired waterbody.

Keywords: Eichhornia crassipes, plantlets, cleaning, impaired waterbody, pond

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Authors: M. Sneha Reddy, M. Arun Kumar, V. Kameswara Rao

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Chromites are binary transition metal oxides with a general formula of ACr₂O₄, where A = Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, and Cu²⁺. Chromites have a normal-type spinel structure with interesting applications in the areas of applied physics, material sciences, and geophysics. They have attracted great consideration because of their unique physicochemical properties and tremendous technological applications in nanodevices, sensor elements, and high-temperature ceramics with useful optical properties. Copper chromite is one of the most efficient spinel oxides, having pronounced commercial application as a catalyst in various chemical reactions like oxidation, hydrogenation, alkylation, dehydrogenation, decomposition of organic compounds, and hydrogen production. Apart from its usage in chemical industries, CuCr₂O₄ finds its major application as a burn rate modifier in solid propellant processing for space launch vehicles globally. Herein we synthesized the nanoparticles of copper chromite using the co-precipitation method. The synthesized nanoparticles were characterized by XRD, TEM, SEM, BET, and TG-DTA. The synthesized nanoparticles of copper chromites were used as a catalyst for the thermal decomposition of various high-energy materials.

Keywords: copper chromite, coprecipitation method, high energy materials, catalytic thermal decomposition

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Authors: Hassiba Bougueria, Nesrine Benarous, Souheyla Chetioui

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Azo dyes are one of the most widely used compounds in organic chemistry, primarily due to their relatively simple preparation methods. They have therefore been widely used, in particular as colorants for textiles, printing inks, cosmetics, and food additives. In addition to their use as dyes, azo compounds have attracted much attention from chemists as their potential applications are important in coordination chemistry, metal-organic frameworks (MOF) structures, COF (covalent-organic frameworks), and catalysis. Moreover, they have found many applications in different fields, such as nonlinear optics, optical storage, photoluminescence, and magnetism. The compound bis{(E)-1-[(2,4,6-tribromophenyl)diazenyl]naphthalen-2-olato}copper(II) dimethyl sulfoxide monosolvate, the CuII atom is tetracoordinate with a square-planar geometry, surrounded by two bidentate (E)-1-[(2,4,6-tribromophenyl)diazenyl]naphthalene-2-olate ligands via two N atoms and two O atoms. The O-Cu-O angles and N-Cu-N are of the order of 177.90(16)° and 177.8(2)°, respectively. The distances Cu-O and Cu- N are 1.892(4) Å and 1.976(4) Å, respectively. The cohesion of the crystal is ensured by hydrogen bonds of the C—H…O type and by π=π staking interactions [centroid–centroid distance = 3.679(4)Å]. The DMSO solvent molecule is disordered at two positions with occupancy rates of 0.70 and 0.30.

Keywords: azo dyes, DRX, structural characterization, biological activity

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Authors: Cesar Torres, Robert Briber, Nam Sun Wang

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Eye drops are the most commonly used treatment for short-term and long-term ophthalmic diseases. However, eye drops could deliver only about 5% of the functional ingredients contained in a burst dosage. To address the limitations of eye drops, the use of therapeutic contact lenses has been introduced. Drug-loaded contact lenses provide drugs a longer residence time in the tear film and hence, decrease the potential risk of side effects. Nevertheless, a major limitation of contact lenses as drug delivery devices is that most of the drug absorbed is released within the first few hours. This fact limits their use for extended release. The present study demonstrates the application of long-alkyl chain ionic surfactants on extending drug release kinetics from commercially available silicone hydrogel contact lenses. In vitro release experiments were carried by immersing drug-containing contact lenses in phosphate buffer saline at physiological pH. The drug concentration as a function of time was monitored using ultraviolet-visible spectroscopy. The results of the study demonstrate that release kinetics is dependent on the ionic surfactant weight percent in the contact lenses, and on the length of the hydrophobic alkyl chain of the ionic surfactants. The use of ionic surfactants in contact lenses can extend the delivery of drugs from a few hours to a few weeks, depending on the physicochemical properties of the drugs. Contact lenses embedded with ionic surfactants could be potential biomaterials to be used for extended drug delivery and in the treatment of ophthalmic diseases. However, ocular irritation and toxicity studies would be needed to evaluate the safety of the approach.

Keywords: contact lenses, drug delivery, controlled release, ionic surfactant

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Authors: Manel Boulakoud, Abdelkader Chouaih, Fodil Hamzaoui

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In the present work we are interested in the determination of the Molecular electrostatic potential (MEP) in Z-3N(2-Ethoxyphenyl), 2-N’(2-Ethoxyphenyl) imino thiazolidin-4-one molecule by ab initio and Density Functional Theory (DFT) in the ground state. The MEP is related to the electronic density and is a very useful descriptor in understanding sites for electrophilic attack and nucleophilic reactions as well as hydrogen bonding interactions. First, geometry optimization was carried out using Hartree–Fock (HF) and DFT methods with 6-311G(d,p) basis set. In order to get more information on the molecule, its stability has been analyzed by natural bond orbital (NBO) analysis. Mulliken population analyses have been calculated. Finally, the molecular electrostatic potential (MEP) and HOMO-LUMO energy levels have been performed. The calculated HOMO and LUMO energies show also the charge transfer within the molecule. The energy gap obtained is about 4 eV which explain the stability of the studied compound. The obtained molecular electrostatic potential from the two methods confirms the nature of the electron charge transfer at the molecular shell and locate the electropositive part and the electronegative part in molecular scale of the title compound.

Keywords: DFT, ab initio, HOMO-LUMO, organic compounds

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Authors: M. Sorahi Nobar, V. Niknam, H. Ebrahimzadeh, H. Soltanloo

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Fusarium graminearum is one of the most destructive crop diseases in the world. Infection occurs during the flowering period in warm and humid conditions. It causes reduction in yield. Moreover, harvested grain is often contaminated with mycotoxins and its acetylated derivatives. Fusarium mycotoxines are potent inhibitor of protein synthesis, and thereby presents hazards for both human and animal health. A rapid production of reactive oxygen intermediates, primarily superoxide and hydrogen peroxide at the site of attempted infection considered as key feature underlying successful pathogen recognition. Here, we compared the time course activity of superoxide dismutase (SOD) as a first line of defenses against ROS- induced oxidative burst between FHB- resistant Sumai3 and susceptible Falat at 48, 96 and 144 hours after infection. Our results showed that Sumai3 SOD activity increased with time and reached the highest-level 4 days after infection while in susceptible cultivar Falat, SOD activity decreased during the first 96 h. after infection. Decreased was followed by an increased at 6 days after infection. According to our results rapid induction of SOD activity in resistant cultivar may play an important role in resistance against FHB in wheat.

Keywords: Fusarium graminearum, mycotoxins, resistant cultivar, superoxide dismutase

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Authors: Afsheen Aman, Shah Ali Ul Qader

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Dextransucrase [EC 2.4.1.5] is a glucosyltransferase that catalysis the biosynthesis of a natural biopolymer called dextran. It can catalyze the transfer of D-glucopyranosyl residues from sucrose to the main chain of dextran. This unique biopolymer has multiple applications in several industries and the key utilization of dextran lies on its molecular weight and the type of branching. Extracellular dextransucrase from Leuconostoc mesenteroides is most extensively studied and characterized. Limited data is available regarding cell-bound or intracellular dextransucrase and on the characterization of dextran produced by in-vitro reaction of intracellular dextransucrase. L. mesenteroides AA1 is reported to produce extracellular dextransucrase that catalyzes biosynthesis of a high molecular weight dextran with only α-(1→6) linkage. Current study deals with the characterization of an intracellular dextransucrase and in vitro biosynthesis of low molecular weight dextran from L. mesenteroides AA1. Intracellular dextransucrase was extracted from cytoplasm and purified to homogeneity for characterization. Kinetic constants, molecular weight and N-terminal sequence analysis of intracellular dextransucrase reveal unique variation with previously reported extracellular dextransucrase from the same strain. In vitro synthesized biopolymer was characterized using NMR spectroscopic techniques. Intracellular dextransucrase exhibited Vmax and Km values of 130.8 DSU ml-1 hr-1 and 221.3 mM, respectively. Optimum catalytic activity was detected at 35°C in 0.15 M citrate phosphate buffer (pH-5.5) in 05 minutes. Molecular mass of purified intracellular dextransucrase is approximately 220.0 kDa on SDS-PAGE. N-terminal sequence of the intracellular enzyme is: GLPGYFGVN that showed no homology with previously reported sequence for the extracellular dextransucrase. This intracellular dextransucrase is capable of in vitro synthesis of dextran under specific conditions. This intracellular dextransucrase is capable of in vitro synthesis of dextran under specific conditions and this biopolymer can be hydrolyzed into different molecular weight fractions for various applications.

Keywords: characterization, dextran, dextransucrase, leuconostoc mesenteroides

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Authors: B. J. Sonani, J. K. Ratnadhariya, Srinivas Palanki

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Cryogenic engineering is the fast growing branch of the modern technology. There are various applications of the cryogenic engineering such as liquefaction in gas industries, metal industries, medical science, space technology, and transportation. The low-temperature technology developed superconducting materials which lead to reduce the friction and wear in various components of the systems. The liquid oxygen, hydrogen and helium play vital role in space application. The liquefaction process is produced very low temperature liquid for various application in research and modern application. The air liquefaction system for oxygen plants in gas industries is based on the Claude cycle. The effect of process parameters on the overall system is difficult to be analysed by manual calculations, and this provides the motivation to use process simulators for understanding the steady state and dynamic behaviour of such systems. The parametric study of this system via MATLAB simulations provide useful guidelines for preliminary design of air liquefaction system based on the Claude cycle. Every organization is always trying for reduce the cost and using the optimum performance of the plant for the staying in the competitive market.

Keywords: cryogenic, liquefaction, low -temperature, oxygen, claude cycle, optimization, MATLAB

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Authors: Ebrahim Tilahun, Erkan Sahinkaya, Bariş Calli̇

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Raw biogas is a valuable renewable energy source however it usually needs removal of the impurities. The presence of hydrogen sulfide (H2S) in the biogas has detrimental corrosion effects on the cogeneration units. Removal of H2S from the biogas can therefore significantly improve the biogas quality. In this work, a conventional bioscrubber (CBS), and a dense membrane bioscrubber (DMBS) were comparatively evaluated in terms of H2S removal efficiency (RE), CH4 enrichment and alkaline consumption at gas residence times ranging from 5 to 20 min. Both bioscrubbers were fed with a synthetic biogas containing H2S (1%), CO2 (39%) and CH4 (60%). The results show that high RE (98%) was obtained in the DMBS when gas residence time was 20 min, whereas slightly lower CO2 RE was observed. While in CBS system the outlet H2S concentration was always lower than 250 ppmv, and its H2S RE remained higher than 98% regardless of the gas residence time, although the high alkaline consumption and frequent absorbent replacement limited its cost-effectiveness. The result also indicates that in DMBS when the gas residence time increased to 20 min, the CH4 content in the treated biogas enriched upto 80%. However, while operating the CBS unit the CH4 content of the raw biogas (60%) decreased by three fold. The lower CH4 content in CBS was probably caused by extreme dilution of biogas with air (N2 and O2). According to the results obtained here the DMBS system is a robust and effective biotechnology in comparison with CBS. Hence, DMBS has a better potential for real scale applications.

Keywords: biogas, bioscrubber, desulfurization, PDMS membrane

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Authors: J. Skibinski, P. Caban, T. Wejrzanowski, K. J. Kurzydlowski

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In the present study numerical simulations of epitaxial growth of gallium nitride in Metal Organic Vapor Phase Epitaxy reactor AIX-200/4RF-S are addressed. The aim of this study was to design the optimal fluid flow and thermal conditions for obtaining the most homogeneous product. Since there are many agents influencing reactions on the crystal growth area such as temperature, pressure, gas flow or reactor geometry, it is difficult to design optimal process. Variations of process pressure and hydrogen mass flow rates have been considered. According to the fact that it’s impossible to determine experimentally the exact distribution of heat and mass transfer inside the reactor during crystal growth, detailed 3D modeling has been used to get an insight of the process conditions. Numerical simulations allow to understand the epitaxial process by calculation of heat and mass transfer distribution during growth of gallium nitride. Including chemical reactions in the numerical model allows to calculate the growth rate of the substrate. The present approach has been applied to enhance the performance of AIX-200/4RF-S reactor.

Keywords: computational fluid dynamics, finite volume method, epitaxial growth, gallium nitride

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Authors: Zarrin Nasri

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Microwave irradiation is an innovative technology in the petroleum industry. This kind of energy has been considered to convert vacuum residue of oil refineries into useful products. The advantages of microwaves energy are short time, fast heating, high energy efficiency, and precise process control. In this paper, the effects of catalyst type and amount have been investigated on upgrading of vacuum residue using microwave irradiation. The vacuum residue used in this research is from Tehran oil refinery, Iran. Additives include different catalysts, active carbon as sensitizer, and sodium borohydride as a solid hydrogen donor. Various catalysts contain iron, nickel, molybdenum disulfide, iron oxide and copper. The amount of catalysts in two cases of presence and absence of sodium borohydride have been evaluated. The objective parameters include temperature, asphaltene, viscosity, and API. The specifications of vacuum residue are API, 8.79, viscosity, 16391 cSt (60°C), asphaltene, 13.3 wt %. The results show that there is a significant difference between the effects of catalysts. Among the used catalysts, Fe powder is the best catalyst for upgrading vacuum residue using microwave irradiation and resulted in asphaltene reduction, 31.3 %; viscosity reduction, 76.43 %; and 23.43 % in API increase.

Keywords: asphaltene, microwave, upgrading, vacuum residue, viscosity

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Authors: M. A. Hasnat, M. Amirul Islam, M. A. Rashed, Jamil. Safwan, M. Mahabubul Alam

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Symmetric (Cu–Pt|Nafion|Pt–Cu) and asymmetric(Pt|Nafion|Pt–Cu) assemblies were fabricated to study the nitrate reduction processes at the cathode. The electrocatalytic nitrate reduction reactions were performed in these assemblies in order to investigate the prerequisite for the enhanced catalytic activity, electrochemical cell durability as well as preferable product selectivity resulting from the reduction of nitrate at the cathode. It has been observed for the symmetric assembly that Cu particles were oxidized on the anode surface under an applied potential and the resulting copper ions migrated to the cathode surface through the Nafion membrane, which deposited as copper oxide on the cathode surface. The formation of this copper oxide covering layer on the Pt–Cu cathode surface is attributed as the reason for the deactivation of the cathode that governed the reduced nitrate reduction along with increasing nitrite selectivity. These problems were addressed and resolved with the asymmetric design of the electrocatalytic reactor, where enhanced hydrogen evolution activates the surface by eroding the CuO over layer as well as speeding up the slow rate determining hydrogenation reactions.

Keywords: membrane, nitrate, electrocatalysis, voltammetry, electrolysis

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Authors: Lucretia Ramnath

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Fishmeal is extensively used for fish farming but is an expensive fish feed ingredient. A cheaper alternate to fishmeal is single cell protein (SCP) which can be cultivated on fermentable sugars recovered from organic waste streams such as pulp and paper mill sludge (PPMS). PPMS has a high cellulose content, thus is suitable for glucose recovery through enzymatic hydrolysis but is hampered by lignin and ash. To render PPMS amenable for enzymatic hydrolysis, the PPMS waspre-treated to produce a glucose-rich hydrolysate which served as a feed stock for the production of fungal SCP. The PPMS used in this study had the following composition: 72.77% carbohydrates, 8.6% lignin, and 18.63% ash. The pre-treatments had no significant effect on lignin composition but had a substantial effect on carbohydrate and ash content. Enzymatic hydrolysis of screened PPMS was previously optimized through response surface methodology (RSM) and 2-factorial design. The optimized protocol resulted in a hydrolysate containing 46.1 g/L of glucose, of which 86% was recovered after downstream processing by passing through a 100-mesh sieve (38 µm pore size). Vogel’s medium supplemented with 10 g/L hydrolysate successfully supported the growth of Fusarium venenatum, conducted using standard growth conditions; pH 6, 200 rpm, 2.88 g/L ammonium phosphate, 25°C. A maximum F. venenatum biomass of 45 g/L was produced with a yield coefficient of 4.67. Pulp and paper mill sludge hydrolysate contained approximately five times more glucose than what was needed for SCP production and served as a suitable carbon source. We have shown that PPMS can be successfully beneficiated for SCP production.

Keywords: pulp and paper waste, fungi, single cell protein, hydrolysate

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Authors: Behzad Panahirad, UğUr Atikol

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The current study is based on a combined heat and power system with multi-objectives, driven by biomass. The system consists of a combustion chamber (CC), a single effect absorption cooling system (SEACS), an air conditioning unit (AC), a reheat steam Rankine cycle (RRC), an organic Rankine cycle (ORC) and an electrolyzer. The purpose of this system is to produce hydrogen, electricity, heat, cooling, and air conditioning. All the simulations had been performed by Engineering Equation Solver (EES) software. Pine sawdust is the selected biofuel for the combustion process. The overall utilization factor (εₑₙ) and exergetic efficiency (ψₑₓ) were calculated to be 2.096 and 24.03% respectively. The performed renewable and environmental impact analysis indicated a sustainability index of 1.316 (SI) and a specific CO2 emission of 353.8 kg/MWh. The parametric study is conducted based on the variation of ambient (sink) temperature, biofuel mass flow rate, and boilers outlet temperatures. The parametric simulation showed that the increase in biofuel mass flow rate has a positive effect on the sustainability of the system.

Keywords: biomass, exergy assessment, multi-objective plant, CO₂ emission, irreversibility

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Authors: Ebrahim Izadi-Darbandi

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In order to investigation the effects of sowing methods, nitrogen and phosphorus application methods in wheat weeds management, an experiment was performed as split plot, based on randomized completely block design with three replications at Research Farm, Faculty of Agriculture, Ferdowsi University of Mashhad, in 2010. Treatments included, wheat sowing methods (single-row with 30 cm distance and twine row on 50 cm width ridges) as main plots and nitrogen and phosphorus application methods (Broadcast and Band) as sub plots. In this experiment, phosphorus and nitrogen sources for fertilization were super phosphate triple (150 kg ha-1) applied before wheat sowing and incorporated with soil and urea (200 kg ha-1) respectively, applied in 2 phases (pre-plant 50%) and near wheat shooting (50%). Results showed that the effect of fertilizers application methods and wheat sowing methods were significant (p≤0.01) on wheat yield increasing and reducing weed-wheat competition. Wheat twine row sowing method, reduced weeds biomass for 25% compared wheat single-row sowing method and increased wheat seed yield and biomass for 60% and 30% respectively. Phosphorus and nitrogen band application reduced weeds biomass for 46% and 53% respectively and increased wheat seed yield for 22% and 33% compared to their broadcast application. The effects of wheat sowing method plus phosphorus and nitrogen application methods interactions, showed that the fertilizers band application and wheat twine-row sowing method were the best methods in wheat yield improvement and reducing wheat-weeds interaction. These results shows that modifying of fertilization methods and wheat sowing method can have important role in fertilizers use efficiency and improving of weeds managements.

Keywords: competition, wheat yield, fertilizer management, biomass

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Authors: Mariia V. Efremova, Iana O. Tcareva, Anastasia D. Blokhina, Ivan S. Grebennikov, Anastasia S. Garanina, Maxim A. Abakumov, Yury I. Golovin, Alexander G. Savchenko, Alexander G. Majouga, Natalya L. Klyachko

Abstract:

During last decades magnetite nanoparticles (NPs) attract a deep interest of scientists due to their potential application in therapy and diagnostics. However, magnetite nanoparticles are toxic and non-stable in physiological conditions. To solve these problems, we decided to create two types of hybrid systems based on magnetite and gold which is inert and biocompatible: gold as a shell material (first type) and gold as separate NPs interfacially bond to magnetite NPs (second type). The synthesis of the first type hybrid nanoparticles was carried out as follows: Magnetite nanoparticles with an average diameter of 9±2 nm were obtained by co-precipitation of iron (II, III) chlorides then they were covered with gold shell by iterative reduction of hydrogen tetrachloroaurate with hydroxylamine hydrochloride. According to the TEM, ICP MS and EDX data, final nanoparticles had an average diameter of 31±4 nm and contained iron even after hydrochloric acid treatment. However, iron signals (K-line, 7,1 keV) were not localized so we can’t speak about one single magnetic core. Described nanoparticles covered with mercapto-PEG acid were non-toxic for human prostate cancer PC-3/ LNCaP cell lines (more than 90% survived cells as compared to control) and had high R2-relaxivity rates (>190 mМ-1s-1) that exceed the transverse relaxation rate of commercial MRI-contrasting agents. These nanoparticles were also used for chymotrypsin enzyme immobilization. The effect of alternating magnetic field on catalytic properties of chymotrypsin immobilized on magnetite nanoparticles, notably the slowdown of catalyzed reaction at the level of 35-40 % was found. The synthesis of the second type hybrid nanoparticles also involved two steps. Firstly, spherical gold nanoparticles with an average diameter of 9±2 nm were synthesized by the reduction of hydrogen tetrachloroaurate with oleylamine; secondly, they were used as seeds during magnetite synthesis by thermal decomposition of iron pentacarbonyl in octadecene. As a result, so-called dumbbell-like structures were obtained where magnetite (cubes with 25±6 nm diagonal) and gold nanoparticles were connected together pairwise. By HRTEM method (first time for this type of structure) an epitaxial growth of magnetite nanoparticles on gold surface with co-orientation of (111) planes was discovered. These nanoparticles were transferred into water by means of block-copolymer Pluronic F127 then loaded with anti-cancer drug doxorubicin and also PSMA-vector specific for LNCaP cell line. Obtained nanoparticles were found to have moderate toxicity for human prostate cancer cells and got into the intracellular space after 45 minutes of incubation (according to fluorescence microscopy data). These materials are also perspective from MRI point of view (R2-relaxivity rates >70 mМ-1s-1). Thereby, in this work magnetite-gold hybrid nanoparticles, which have a strong potential for biomedical application, particularly in targeted drug delivery and magnetic resonance imaging, were synthesized and characterized. That paves the way to the development of special medicine types – theranostics. The authors knowledge financial support from Ministry of Education and Science of the Russian Federation (14.607.21.0132, RFMEFI60715X0132). This work was also supported by Grant of Ministry of Education and Science of the Russian Federation К1-2014-022, Grant of Russian Scientific Foundation 14-13-00731 and MSU development program 5.13.

Keywords: drug delivery, magnetite-gold, MRI contrast agents, nanoparticles, toxicity

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Authors: Sukanya Devi Ramachandran, Vaishnavi Muralidharan, Kavya Chandrasekaran

Abstract:

Polycaprolactone is polymer belonging to the polyester family that has noticeable characteristics of biodegradability and biocompatibility which is essential for medical applications. Polycaprolactone is produced by the ring opening polymerization of the monomer epsilon-Caprolactone (ε-CL) which is a closed ester, comprising of seven-membered ring. This process is normally catalysed by metallic components such as stannous octoate. It is difficult to remove the catalysts after the reaction, and they are also toxic to the human body. An alternate route of using enzymes as catalysts is being employed to reduce the toxicity. Lipase enzyme is a subclass of esterase that can easily attack the ester bonds of ε-CL. This research paper throws light on the extraction of lipase from germinating sunflower seeds and the activity of the biocatalyst in the polymerization of ε-CL. Germinating Sunflower seeds were crushed with fine sand in phosphate buffer of pH 6.5 into a fine paste which was centrifuged at 5000rpm for 10 minutes. The clear solution of the enzyme was tested for activity at various pH ranging from 5 to 7 and temperature ranging from 40oC to 70oC. The enzyme was active at pH6.0 and at 600C temperature. Polymerization of ε-CL was done using toluene as solvent with the catalysis of lipase enzyme, after which chloroform was added to terminate the reaction and was washed in cold methanol to obtain the polymer. The polymerization was done by varying the time from 72 hours to 6 days and tested for the molecular weight and the conversion of the monomer. The molecular weight obtained at 6 days is comparably higher. This method will be very effective, economical and eco-friendly to produce as the enzyme used can be regenerated as such at the end of the reaction and can be reused. The obtained polymers can be used for drug delivery and other medical applications.

Keywords: lipase, monomer, polycaprolactone, polymerization

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Authors: Jina Lee

Abstract:

Methane gas is a common byproduct in any process of rot and degradation of organic matter. This gas, when decomposition occurs, is emitted directly into the atmosphere. Methane is the simplest alkane hydrocarbon that exists. Its chemical formula is CH₄. This means that there are four atoms of hydrogen and one of carbon, which is linked by covalent bonds. Methane is found in nature in the form of gas at normal temperatures and pressures. In addition, it is colorless and odorless, despite being produced by the rot of plants. It is a non-toxic gas, and the only real danger is that of burns if it were to ignite. There are several ways to generate methane gas in homes, and the amount of methane gas generated by the decomposition of organic matter varies depending on the type of matter in question. An experiment was designed to measure the efficiency, such as a relationship between the amount of raw material and the amount of gas generated, of three different mixtures of organic matter: 1. food remains of home; 2. animal waste (excrement) 3. equal parts mixing of food debris and animal waste. The results allowed us to conclude which of the three mixtures is the one that grants the highest efficiency in methane gas generation and which would be the most suitable for methane gas generation systems for homes in order to occupy less space generating an equal amount of gas.

Keywords: alternative energy source, energy conversion, methane gas conversion system, waste management

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Authors: C. S. Sona, Makrand A. Khanwale, Channamallikarjun S. Mathpati

Abstract:

New generation nuclear power plants are currently being developed to be highly economical, to be passive safe, to produce hydrogen. An important feature of these reactors will be the use of coolants at temperature higher than that being used in current nuclear reactors. The molten fluoride salt with a eutectic composition of 46.5% LiF - 11.5% NaF - 42% KF (mol %) commonly known as FLiNaK is a leading candidate for heat transfer coolant for these nuclear reactors. CFD simulations were carried out using large eddy simulations to investigate the flow characteristics of molten FLiNaK at 850°C at a Reynolds number of 10,500 in a cylindrical pipe. Simulation results have been validated with the help of mean velocity profile using direct numerical simulation data. Transient velocity information was used to identify and characterise turbulent structures which are important for transfer of heat across solid-fluid interface. A wavelet transform based methodology called wavelet transform modulus maxima was used to identify and characterise the singularities. This analysis was also used for flow visualisation, and also to calculate the heat transfer coefficient using small eddy model. The predicted Nusselt number showed good agreement with the available experimental data.

Keywords: FLiNaK, heat transfer, molten salt, turbulent structures

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Authors: Gyati Shilakari Asthana, Abhay Asthana, Dharm Veer Kohli, Suresh Prasad Vyas

Abstract:

Purpose: The therapeutic potential of oligonucleotide (ODN) is primarily dependent upon its safe and efficient delivery to specific cells overcoming degradation and maximizing cellular uptake in vivo. The present study is focused to design low molecular weight chitosan nanoconstructs to meet the requirements of safe and effectual delivery of ODNs. LMW-chitosan is a biodegradable, water soluble, biocompatible polymer and is useful as a non-viral vector for gene delivery due to its better stability in water. Methods: LMW chitosan ODN nanoparticles (CHODN NPs) were formulated by self-assembled method using various N/P ratios (moles ratio of amine groups of CH to phosphate moieties of ODNs; 0.5:1, 1:1, 3:1, 5:1, and 7:1) of CH to ODN. The developed CHODN NPs were evaluated with respect to gel retardation assay, particle size, zeta potential and cytotoxicity and transfection efficiency. Results: Complete complexation of CH/ODN was achieved at the charge ratio of 0.5:1 or above and CHODN NPs displayed resistance against DNase I. On increasing the N/P ratio of CH/ODN, the particle size of the NPs decreased whereas zeta potential (ZV) value increased. No significant toxicity was observed at all CH concentrations. The transfection efficiency was increased on increasing N/P ratio from 1:1 to 3:1, whereas it was decreased with further increment in N/P ratio upto 7:1. Maximum transfection of CHODN NPs with both the cell lines (Raw 267.4 cells and Hela cells) was achieved at N/P ratio of 3:1. The results suggest that transfection efficiency of CHODN NPs is dependent on N/P ratio. Conclusion: Thus the present study states that LMW chitosan nanoparticulate carriers would be acceptable choice to improve transfection efficiency in vitro as well as in vivo delivery of oligonucleotide.

Keywords: LMW-chitosan, chitosan nanoparticles, biocompatibility, cytotoxicity study, transfection efficiency, oligonucleotide

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Authors: Kanchan J. Kakade, S. A. Annadate

Abstract:

This paper presents design and development of underground coal mine monitoring using mbed arm cortex controller and ZigBee communication. Coal mine is a special type of mine which is dangerous in nature. Safety is the most important feature of a coal industry for proper functioning. It’s not only for employees and workers but also for environment and nation. Many coal producing countries in the world face phenomenal frequently occurred accidents in coal mines viz, gas explosion, flood, and fire breaking out during coal mines exploitation. Thus, such emissions of various gases from coal mines are necessary to detect with the help of robot. Coal is a combustible, sedimentary, organic rock, which is made up of mainly carbon, hydrogen and oxygen. Coal Mine Detection Robot mainly detects mash gas and carbon monoxide. The mash gas is the kind of the mixed gas which mainly make up of methane in the underground of the coal mine shaft, and sometimes it abbreviate to methane. It is formed from vegetation, which has been fused between other rock layers and altered by the combined effects of heat and pressure over millions of years to form coal beds. Coal has many important uses worldwide. The most significant uses of coal are in electricity generation, steel production, cement manufacturing and as a liquid fuel.

Keywords: Zigbee communication, various sensors, hazardous gases, mbed arm cortex M3 core controller

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Authors: Shruti Malviya, Chris Bowler

Abstract:

Environmental processes acting at multiple spatial scales control marine diatom community structure. However, the contribution of local factors (e.g., temperature, salinity, etc.) in these highly complex systems is poorly understood. We, therefore, investigated the diatom community organization as a function of environmental predictors and determined the relative contribution of various environmental factors on the structure of marine diatoms assemblages in the world’s ocean. The dataset for this study was derived from the Tara Oceans expedition, constituting 46 sampling stations from diverse oceanic provinces. The V9 hypervariable region of 18s rDNA was organized into assemblages based on their distributional co-occurrence. Using Ward’s hierarchical clustering, nine clusters were defined. The number of ribotypes and reads varied within each cluster-three clusters (II, VIII and IX) contained only a few reads whereas two of them (I and IV) were highly abundant. Of the nine clusters, seven can be divided into two categories defined by a positive correlation with phosphate and nitrate and a negative correlation with longitude and, the other by a negative correlation with salinity, temperature, latitude and positive correlation with Lyapunov exponent. All the clusters were found to be remarkably dominant in South Pacific Ocean and can be placed into three classes, namely Southern Ocean-South Pacific Ocean clusters (I, II, V, VIII, IX), South Pacific Ocean clusters (IV and VII), and cosmopolitan clusters (III and VI). Our findings showed that co-occurring ribotypes can be significantly associated into recognizable clusters which exhibit a distinct response to environmental variables. This study, thus, demonstrated distinct behavior of each recognized assemblage displaying a taxonomic and environmental signature.

Keywords: assemblage, diatoms, hierarchical clustering, Tara Oceans

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Authors: Brian J. Graham, Ronald T. Raines

Abstract:

The presence of a nearly vacant p orbital on boron endows boronic acids with unique abilities as a catalyst and ligand. An organocatalytic process has been developed for the conversion of biomass-derived sugars to 5-hydroxymethylfurfural, which is a platform chemical. Specifically, 2-carboxyphenylboronic acid (2-CPBA) has been shown to be an optimal catalyst for this process, promoting the desired transformation in the absence of metals. The attributes of 2-CPBA as a catalyst led to additional investigations of its structure and reactivity. 2-CPBA was found to exist as a cyclized benzoxaborolone adduct rather than a free carboxylic acid. This cyclization has profound consequences for the oxidative stability of the boronic acid. Stereoelectronic effects within the oxaborolone ring destabilize the oxidation transition state by reducing electron donation from the cyclic oxygen to the developing p orbital on boron. That leads to a 10,000-fold increase in oxidative stability while maintaining the normal reactivity of boronic acids toward diols (e.g., carbohydrates) and nucleophiles in proteins while also presenting numerous hydrogen-bond accepting and donating groups. Thus, benzoxaborolones are useful in catalysis, chemical biology, medicinal chemistry, and allied fields.

Keywords: bioisosteres, boronic acid, catalysis, oxidative stability, pharmacophore, stereoelectronic effects

Procedia PDF Downloads 166

Authors: M. D. Asemoloye, S. G. Jonathan, A. Rafiq, O. J. Olawuyi, D. O. Adejoye

Abstract:

Calmodulin is one of the intracellular calcium proteins that regulates large spectrum of enzymes and cellular functions including metabolism of cyclic nucleotides and glycogen. The potentials of calmodulin gene in fungi necessitates their genetic response and their strong cassette of enzyme secretions for pesticide degradation. Therefore, this study was carried out to investigate the ‘Transcriptomic’ response of calmodulin encoding genes in Talaromyces fungi in response to 2, 2-dichlorovinyl dimethyl phosphate (DDVP or Dichlorvos) an organophosphate pesticide and γ-Hexachlorocyclohexane (Lindane) an organochlorine pesticide. Fungi strains isolated from rhizosphere from grasses rhizosphere in pesticide polluted sites were subjected to percentage incidence test. Two most frequent fungi were further characterized using ITS gene amplification (ITS1 and ITS4 combinations), they were thereafter subjected to In-vitro DDVP and lindane tolerance tests at different concentrations. They were also screened for presence and expression of calmodulin gene (caM) using RT-PCR technique. The two Talaromyces strains had the highest incidence of 50-72% in pesticide polluted site, they were both identified as Talaromyces astroroseus asemoG and Talaromyces purpurogenum asemoN submitted in NCBI gene-bank with accession numbers KY488464 and KY488468 respectively. T. astroroseus KY488464 tolerated DDVP (1.23±0.023 cm) and lindane (1.11±0.018 cm) at 25 % concentration while T. purpurogenum KY488468 tolerated DDVP (1.33±0.061 cm) and lindane (1.54±0.077 cm) at this concentration. Calmodulin gene was detected in both strains, but RT-PCR expression of caM gene revealed at 900-1000 bp showed an under-expression of caM in T. astrorosues KY488464 but overexpressed in T. purpurogenum KY488464. Thus, the calmodulin gene response of these fungal strains to both pesticides could be considered in monitoring the potentials of fungal strains to pesticide tolerance and bioremediation of pesticide in polluted soil.

Keywords: Calmodulin gene, pesticide, RT-PCR, talaromyces, tolerance

Procedia PDF Downloads 199

Authors: Jenaidullah Batur, Sebghatullah Mudaber

Abstract:

Currently, there is a list of catalysts that can reduce CO₂ to valuable chemicals and fuels, among them metal oxides such as TiO₂, known as promising photocatalysts to produce hydrogen and CO unless they are at an earlier age and still need to promote activity to able for produce fabricated values. Herein, in this work, we provided a novel, facile and eco-friendly synthesis strategy to synthesize more effective TiO₂-organic composite materials to selectively reduce CO₂ to CO. In this experiment, commercial nanocrystalline TiO₂ and saccharin with Li (LiBr, LiCl) were synthesized using the facile physical grinding in the motel pestle for 10 minutes, then added 10 mL of deionized water (18.2 megaohms) on the 300mg composite catalyst before samples moving for hydrothermal heating for 24 hours at 80 C in the oven. Compared with nanosized TiO₂, the new TiO₂-Sac-Li indeed displays a high CO generation rate of 70.83 μmol/g/h, which is 7 times higher than TiO₂, which shows enhancement in CO₂ reduction and an apparent improvement in charge carrier dynamic. The CO₂ reduction process at the gas-solid interface on TiO₂-Sac-Li composite semiconductors is investigated by functional calculations and several characterization methods. The results indicate that CO₂ can be easily activated by the TiO₂-Sac-Li atoms on the surface. This work innovatively investigates CO₂ reduction in novel composite materials and helps to broaden the applications of composite materials semiconductors.

Keywords: green chemistry, green synthesis, TiO₂, photocatalyst

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