Search results for: oil absorption
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1596

Search results for: oil absorption

576 Demetallization of Crude Oil: Comparative Analysis of Deasphalting and Electrochemical Removal Methods of Ni and V

Authors: Nurlan Akhmetov, Abilmansur Yeshmuratov, Aliya Kurbanova, Gulnar Sugurbekova, Murat Baisariyev

Abstract:

Extraction of the vanadium and nickel compounds is complex due to the high stability of porphyrin, nickel is catalytic poison which deactivates catalysis during the catalytic cracking of the oil, while vanadyl is abrasive and valuable metal. Thus, high concentration of the Ni and V in the crude oil makes their removal relevant. Two methods of the demetallization of crude oil were tested, therefore, the present research is conducted for comparative analysis of the deasphalting with organic solvents (cyclohexane, carbon tetrachloride, chloroform) and electrochemical method. Percentage of Ni extraction reached maximum of approximately 55% by using the electrochemical method in electrolysis cell, which was developed for this research and consists of three sections: oil and protonating agent (EtOH) solution between two conducting membranes which divides it from two capsules of 10% sulfuric acid and two graphite electrodes which cover all three parts in electrical circuit. Ions of metals pass through membranes and remain in acid solutions. The best result was obtained in 60 minutes with ethanol to oil ratio 25% to 75% respectively, current fits in to the range from 0.3A to 0.4A, voltage changed from 12.8V to 17.3V. Maximum efficiency of deasphalting, with cyclohexane as the solvent, in Soxhlet extractor was 66.4% for Ni and 51.2% for V. Thus, applying the voltammetry, ICP MS (Inductively coupled plasma mass spectrometry) and AAS (atomic absorption spectroscopy), these mentioned types of metal extraction methods were compared in this paper.

Keywords: electrochemistry, deasphalting of crude oil, demetallization of crude oil, petrolium engineering

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575 Formulation Development and Evaluation Chlorpheniramine Maleate Containing Nanoparticles Loaded Thermo Sensitive in situ Gel for Treatment of Allergic Rhinitis

Authors: Vipin Saini, Manish Kumar, Shailendra Bhatt, A. Pandurangan

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The aim of the present study was to fabricate a thermo sensitive gel containing Chlorpheniramine maleate (CPM) loaded nanoparticles following intranasal administration for effective treatment of allergic rhinitis. Chitosan based nanoparticles were prepared by precipitation method followed by the addition of developed NPs within the Poloxamer 407 and carbopol 934P based mucoadhesive thermo-reversible gel. Developed formulations were evaluated for Particle size, PDI, % entrapment efficiency and % cumulative drug permeation. NP3 formulation was found to be optimized on the basis of minimum particle size (143.9 nm), maximum entrapment efficiency (80.10±0.414 %) and highest drug permeation (90.92±0.531 %). The optimized formulation NP3 was then formulated into thermo reversible in situ gel. This intensifies the contact between nasal mucosa and the drug, increases and facilitates the drug absorption which results in increased bioavailability. G4 formulation was selected as the optimize on the basis of gelation ability and mucoadhesive strength. Histology was carried out to examine the damage caused by the optimized G4 formulation. Results revealed no visual signs of tissue damage thus indicated safe nasal delivery of nanoparticulate in situ gel formulation G4. Thus, intranasal CPM NP-loaded in situ gel was found to be a promising formulation for the treatment of allergic rhinitis.

Keywords: chitosan, nanoparticles, in situ gel, chlorpheniramine maleate, poloxamer 407

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574 Seasonal Variation of the Impact of Mining Activities on Ga-Selati River in Limpopo Province, South Africa

Authors: Joshua N. Edokpayi, John O. Odiyo, Patience P. Shikwambana

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Water is a very rare natural resource in South Africa. Ga-Selati River is used for both domestic and industrial purposes. This study was carried out in order to assess the quality of Ga-Selati River in a mining area of Limpopo Province-Phalaborwa. The pH, Electrical Conductivity (EC) and Total Dissolved Solids (TDS) were determined using a Crinson multimeter while turbidity was measured using a Labcon Turbidimeter. The concentrations of Al, Ca, Cd, Cr, Fe, K, Mg, Mn, Na and Pb were analysed in triplicate using a Varian 520 flame atomic absorption spectrometer (AAS) supplied by PerkinElmer, after acid digestion with nitric acid in a fume cupboard. The average pH of the river from eight different sampling sites was 8.00 and 9.38 in wet and dry season respectively. Higher EC values were determined in the dry season (138.7 mS/m) than in the wet season (96.93 mS/m). Similarly, TDS values were higher in dry (929.29 mg/L) than in the wet season (640.72 mg/L) season. These values exceeded the recommended guideline of South Africa Department of Water Affairs and Forestry (DWAF) for domestic water use (70 mS/m) and that of the World Health Organization (WHO) (600 mS/m), respectively. Turbidity varied between 1.78-5.20 and 0.95-2.37 NTU in both wet and dry seasons. Total hardness of 312.50 mg/L and 297.75 mg/L as the concentration of CaCO3 was computed for the river in both the wet and the dry seasons and the river water was categorised as very hard. Mean concentration of the metals studied in both the wet and the dry seasons are: Na (94.06 mg/L and 196.3 mg/L), K (11.79 mg/L and 13.62 mg/L), Ca (45.60 mg/L and 41.30 mg/L), Mg (48.41 mg/L and 44.71 mg/L), Al (0.31 mg/L and 0.38 mg/L), Cd (0.01 mg/L and 0.01 mg/L), Cr (0.02 mg/L and 0.09 mg/L), Pb (0.05 mg/L and 0.06 mg/L), Mn (0.31 mg/L and 0.11 mg/L) and Fe (0.76 mg/L and 0.69 mg/L). Results from this study reveal that most of the metals were present in concentrations higher than the recommended guidelines of DWAF and WHO for domestic use and the protection of aquatic life.

Keywords: contamination, mining activities, surface water, trace metals

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573 Characteristic Study of Polymer Sand as a Potential Substitute for Natural River Sand in Construction Industry

Authors: Abhishek Khupsare, Ajay Parmar, Ajay Agarwal, Swapnil Wanjari

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The extreme demand for aggregate leads to the exploitation of river-bed for fine aggregates, affecting the environment adversely. Therefore, a suitable alternative to natural river sand is essentially required. This study focuses on preventing environmental impact by developing polymer sand to replace natural river sand (NRS). Development of polymer sand by mixing high volume fly ash, bottom ash, cement, natural river sand, and locally purchased high solid content polycarboxylate ether-based superplasticizer (HS-PCE). All the physical and chemical properties of polymer sand (P-Sand) were observed and satisfied the requirement of the Indian Standard code. P-Sand yields good specific gravity of 2.31 and is classified as zone-I sand with a satisfactory friction angle (37˚) compared to natural river sand (NRS) and Geopolymer fly ash sand (GFS). Though the water absorption (6.83%) and pH (12.18) are slightly more than those of GFS and NRS, the alkali silica reaction and soundness are well within the permissible limit as per Indian Standards. The chemical analysis by X-Ray fluorescence showed the presence of high amounts of SiO2 and Al2O3 with magnitudes of 58.879% 325 and 26.77%, respectively. Finally, the compressive strength of M-25 grade concrete using P-sand and Geopolymer sand (GFS) was observed to be 87.51% and 83.82% with respect to natural river sand (NRS) after 28 days, respectively. The results of this study indicate that P-sand can be a good alternative to NRS for construction work as it not only reduces the environmental effect due to sand mining but also focuses on utilising fly ash and bottom ash.

Keywords: polymer sand, fly ash, bottom ash, HSPCE plasticizer, river sand mining

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572 Silver Grating for Strong and Reproducible SERS Response

Authors: Y. Kalachyova, O. Lyutakov, V. Svorcik

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One of the most significant obstacles for the application of surface enhanced Raman spectroscopy (SERS) is the poor reproducibility of SERS active substrates: SERS intensity can be varied from one substrate to another and moreover along the one substrate surface. High enhancement of the near-field intensity is the key factor for ultrasensitive SERS realization. SERS substrate can be prepared through introduction of highly ordered metal array, where light focusing is achieved through excitation of surface plasmon-polaritons (SPPs). In this work, we report the preparation of silver nanostructures with plasmon absorption peaks tuned by the metal arrangement. Excimer laser modification of poly(methyl methacrylate) followed by silver evaporation is proposed as an effective way for the creation of reproducible and effective surface plasmon-polaritons (SPP)-based SERS substrate. Theoretical and experimental studies were performed to optimize structure parameter for effective SPP excitation. It was found that the narrow range of grating periodicity and metal thickness exist, where SPPs can be most efficiently excited. In spite of the fact, that SERS response was almost always achieved, the enhancement factor was found to vary more with the effectivity of SPP excitation. When the real structure parameters were set to optimal for SPP excitation, a SERS enhancement factor was achieved up to four times. Theoretical and experimental investigation of SPP excitation on the two-dimensional periodical silver array was performed with the aim to make SERS response as high as possible.

Keywords: grating, nanostructures, plasmon-polaritons, SERS

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571 Comparison of Physicochemical Properties of DNA-Ionic Liquids Complexes

Authors: Ewelina Nowak, Anna Wisla-Swider, Gohar Khachatryan, Krzysztof Danel

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Complexes of ionic liquids with different heterocyclic-rings were synthesized by ion exchange reactions with pure salmon DNA. Ionic liquids (ILs) like 1-hexyl-3-methylimidazolium chloride, 1-butyl-4-methylpyridinium chloride and 1-ethyl-1-methylpyrrolidinium bromide were used. The ILs were built into helical state and confirmed by IR spectrometric techniques. Patterns of UV-Vis, photoluminescence, IR, and CD spectra indicated inclusion of small molecules into DNA structure. Molecular weight and radii of gyrations values of ILs-DNA complexes chains were established by HPSEC–MALLS–RI method. Modification DNA with 1-ethyl-1-methylpyrrolidinium bromide gives more uniform material and leads to elimination of high molecular weight chains. Thus, the incorporation DNA double helical structure with both 1-hexyl-3-methylimidazolium chloride and 1-butyl-4-methylpyridinium chloride exhibited higher molecular weight values. Scanning electron microscopy images indicate formation of nanofibre structures in all DNA complexes. Fluorescence depends strongly on the environment in which the chromophores are inserted and simultaneously on the molecular interactions with the biopolymer matrix. The most intensive emission was observed for DNA-imidazole ring complex. Decrease in intensity UV-Vis peak absorption is a consequence of a reduction in the spatial order of polynucleotide strands and provides different π–π stacking structure. Changes in optical properties confirmed by spectroscopy methods make DNA-ILs complexes potential biosensor applications.

Keywords: biopolymers, biosensors, cationic surfactant, DNA, DNA-gels

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570 Cross Section Measurement for Formation of Metastable State of ¹¹¹ᵐCd through ¹¹¹Cd (γ, γ`) ¹¹¹ᵐCd Reaction Induced by Bremsstrahlung Generated through 6 MeV Electrons

Authors: Vishal D. Bharud, B. J. Patil, S. S. Dahiwale, V. N. Bhoraskar, S. D. Dhole

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Photon induced average reaction cross section of ¹¹¹Cd (γ, γ`) ¹¹¹ᵐCd reaction was experimentally determined for the bremsstrahlung energy spectrum of 6 MeV by utilizing the activation and offline γ-ray spectrometric techniques. The 6 MeV electron accelerator Racetrack Microtron of Savitribai Phule Pune University, Pune was used for the experimental work. The bremsstrahlung spectrum generated by bombarding 6 MeV electrons on lead target was theoretically estimated by FLUKA code. Bremsstrahlung radiation can have energies exceeding the threshold of the particle emission, which is normally above 6 MeV. Photons of energies below the particle emission threshold undergo absorption into discrete energy levels, with possibility of exciting nuclei to excited state including metastable state. The ¹¹¹Cd (γ, γ`) ¹¹¹ᵐCd reaction cross sections were calculated at different energies of bombarding Photon by using the TALYS 1.8 computer code with a default parameter. The focus of the present work was to study the (γ,γ’) reaction for exciting ¹¹¹Cd nuclei to metastable states which have threshold energy below 3 MeV. The flux weighted average cross section was obtained from the theoretical values of TALYS 1.8 and TENDL 2017 and is found to be in good agreement with the present experimental cross section.

Keywords: bremsstrahlung, cross section, FLUKA, TALYS-1.8

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569 Removal of Heavy Metals Pb, Zn and Cu from Sludge Waste of Paper Industries Using Biosurfactant

Authors: Nurul Hidayati

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Increasing public awareness of environmental pollution influences the search and development of technologies that help in clean up of organic and inorganic contaminants such as metals. Sludge waste of paper industries as toxic and hazardous material from specific source contains Pb, Zn, and Cu metal from waste soluble ink. An alternative and eco-friendly method of remediation technology is the use of biosurfactants and biosurfactant-producing microorganisms. Soil washing is among the methods available to remove heavy metal from sediments. The purpose of this research is to study effectiveness of biosurfactant with concentration = CMC for the removal of heavy metals, lead, zinc and copper in batch washing test under four different biosurfactant production by microbial origin. Pseudomonas putida T1(8), Bacillus subtilis 3K, Acinetobacter sp, and Actinobacillus sp was grown on mineral salt medium that had been already added with 2% concentration of molasses that it is a low cost application. The samples were kept in a shaker 120 rpm at room temperature for 3 days. Supernatants and sediments of sludge were separated by using a centrifuge and samples from supernatants were measured by atomic absorption spectrophotometer. The highest removal of Pb was up to 14,04% by Acinetobacter sp. Biosurfactant of Pseudomonas putida T1(8) have the highest removal for Zn and Cu up to 6,5% and 2,01% respectively. Biosurfactants have a role for removal process of the metals, including wetting, contact of biosurfactant to the surface of the sediments and detachment of the metals from the sediment. Biosurfactant has proven its ability as a washing agent in heavy metals removal from sediments, but more research is needed to optimize the process of removal heavy metals.

Keywords: biosurfactant, removal of heavy metals, sludge waste, paper industries

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568 Silver Nanoparticles Loaded Cellulose Nanofibers (Cnf)/mesoporous Bioactive Glass Hydrogels For Periodontitis Treatment

Authors: Anika Pallapothu

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Periodontitis, a severe gum disease, poses a significant threat to the integrity of bone and soft tissues supporting teeth, primarily initiated by bacterial accumulation around the gum line. Conventional treatments like scaling/root planning and plaque removal are widely employed, but integrating modern technologies such as nanotechnology holds promise for innovative therapeutic approaches. This study explores the utilization of silver nanoparticles encapsulated within cellulose nanofiber (CNF) and mesoporous bioactive glass hydrogel matrices for periodontitis management. Silver nanoparticles exhibit potent antimicrobial properties by disrupting microbial cell membranes, inducing reactive oxygen species (ROS) generation, and interfering with vital cellular processes like ATP production and nucleic acid synthesis. Mesoporous bioactive glass, renowned for its high surface area, osteoconductive, and bioactivity, presents a favorable platform for pharmaceutical applications. Incorporating CNF enhances the properties of the hydrogel due to its biocompatibility, biodegradability, and water absorption capacity. The proposed composite material is anticipated to exert beneficial effects in periodontitis treatment by demonstrating antibacterial and anti-inflammatory activities, offering a promising avenue for future therapeutic interventions.

Keywords: periodontitis, cellulose nanofibers, silver nanoparticles, mesoporous bioactive glass, antibacterial activity, anti-inflammatory activity

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567 Rapid Biosynthesis of Silver Nanoparticles Using Trachyspermum Ammi

Authors: Rajesh Kumar Meena, Suman Jhajharia, Goutam Chakraborty

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Plasmonic silver nanoparticles (Ag NPs) was synthesized by chemical reduction method using Trachyspermum Ammi (TA, Ajwain) seeds extract in aqueous medium and AgNO3 solution at different time interval. Reaction time, and concentration of AgNO3 and TA could accelerate the reduction rate of Ag+ and affect AgNPs size and concentration of NPs. Surface plasmon resonance band centered at 420-430 nm (88.78nm) was recognised as first exitonic peak of UV-Vis absorption spectra of AgNPs that used to calculate the particle size (10-30 nm). FTIR results TA supported AgNPs showed decrease in intensity of peaks at 3394, 1716 and 1618 cm-1 with respect to the plain TA indicating the involvement of O-H, carbonyl group and C=C stretching in formation of TA-AgNPs aggregates. The C-O-C and C-N stretching suggested the presence of many phytochemicals on the surface of the NPs. Impedance study reveals that at low concentration of TA the rate of charge transfer is in TA-AgNPs aggregates, found higher than the higher TA concentration condition that confirms the stability of AgNPs in water. Extract reduce silver ions into silver nanoparticles (NPs) of size 6-50nm. Pronounce effect of the time on Ag NPs concentration and particle size, was exhibited by the system These biogenic Ag NPs are characterized using UV- Vis spectrophotometry (UV-Visible), Fourier transformation infrared (FTIR) and XRD. These studies give us inside view of the most probable mechanism of biosynthesis and optoelectronic properties of the as synthesised Ag NPs.

Keywords: antimicrobial activity, bioreduction, capping agent, silver nanoparticles

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566 In vitro P-Glycoprotein Modulation: Combinatorial Approach Using Natural Products

Authors: Jagdish S. Patel, Piyush Chudasama

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Context: Over-expression of P-glycoprotein (P-gp) plays critical role in absorption of many drug candidates which results into lower bioavailability of the drug. P-glycoprotein also over expresses in many pathological conditions like diabetes, affecting the drug therapy. Modulation of P-gp expression using inhibitors can help in designing novel formulation enhancing the bioavailability of the drug in question. Objectives: The main focus of the study was to develop advanced glycation end products (AGEs) induced P-gp over expression in Caco-2 cells. Curcumin, piperine and epigallocatechin gallate were used to evaluate their P-gp inhibitory action using combinatorial approach. Materials and methods: Methylglyoxal (MG) induced P-gp over expression was checked in Caco-2 cells using real time PCR. P-gp inhibitory effects of the phytochemicals were measured after induction with MG alone and in combination of any two compounds. Cytotoxicity of each of the phytochemical was evaluated using MTT assay. Results: Induction with MG (100mM) significantly induced the over expression of P-glycoprotein in Caco-2 cells after 24 hr. Curcumin, piperine and epigallocatechin gallate alone significantly reduced the level of P-gp within 6 hr of treatment period monitored by real time PCR. The combination of any two phytochemical also down regulated the expression of P-gp in cells. Combinations of Curcumin and epigallocatechin gallate have shown significant down regulation when compared with other two combinations. Conclusions: Combinatorial approach for down regulating the expression of P-gp, in pathological conditions like diabetes, has demonstrated promising approach for therapeutic purpose.

Keywords: p-glycoprotein, curcumin, piperine, epigallocatechin gallate, p-gp inhibition

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565 The Influence of Colloidal Metal Nanoparticles on Growth and Proliferation of in Vitro Cultures of Potato

Authors: Przewodowski Włodzimierz, Przewodowska Agnieszka, Sekrecka Danuta, Michałowska Dorota

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Colloidal metal nanoparticles are widely applied in various areas and have great potential in different biotechnological applications. Their particular properties associated with both the antiseptic, antioxidant and anti aging properties as well as ability to penetrate most of the biological barriers, synergy in the absorption of nutrients and nontoxic to plants. The properties make them potentially useful in the fast and safe production of healthy, certified starting material in the production of plants exposed to many pathogenic microorganisms causing serious diseases, significantly affecting yield and causing the economic losses. In this case it is crucial to provide appropriate conditions for the production, storage and distribution of the plant material. Therefore, the aim of the proposed research was to develop and identify the influence of four colloidal metal nanoparticles on growth and proliferation of in vitro cultures of potato (Solanum tuberosum) - one of the most economically important strategic crops in the world. The research on different varieties of potato was performed by placing the explants of the in vitro cultures on sterile Murashige and Skoog (MS) type medium. The influence of the nanocolloids was evaluated using the MS medium impregnated with the examinated nanoparticles. The vigour of growth and the rate of proliferation was examinated for 6-8 weeks with both night/day-length and temperature over the ranges 8/16 h and 20–22 °C respectively. The results of our preliminary work confirmed high usefulness of the nanocolloids in the safe production of the examinated in vitro cultures.

Keywords: colloidal metal nanoparticles, in vitro cultures, potato, propagation

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564 Using Medicinal Herbs in Designing Green Roofs

Authors: Mohamad Javad Shakouri, Behshad Riahipour

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Today, the use of medicinal herbs in architecture and green space has a significant effect on the process of calming human and increases the reliability coefficient of design and design flexibility. The current research was conducted with the aim to design green roof and investigate the effect of medicinal herbs such as cress, leek, fenugreek, beet, sweet fennel, green basil, purple basil, and purslane on reducing the number of environmental pollutants (copper, zinc, and cadmium). Finally, the weight of the dry plant and the concentration of elements zinc, lead, and cadmium in the herbs was measured. According to the results, the maximum dry weight (88.10 and 73.79 g) was obtained in beet and purslane respectively and the minimum dry weight (24.12 and 25.21) was obtained in purple basil, and green basil respectively. The maximum amount of element zinc (235 and 213 mg/kg) and the maximum amount of lead (143 mg/kg) were seen in sweet fennel and purple basil. In addition, the maximum amount of cadmium (13 mg/kg) was seen in sweet fennel and purple basil and the minimum amount of lead and cadmium (78 and 7 mg/kg) was seen in green basil, and the minimum amount of zinc (110 mg/kg) was seen in leek. On the other hand, the absorption amount of element lead in the herbs beet and purslane was the same and both absorbed 123 mg/kg lead. Environmentally, if green roofs are implemented extensively and in wide dimensions in urban spaces, they will purify and reduce pollution significantly by absorbing carbon dioxide and producing oxygen.

Keywords: medicinal herbs, green space, green roof, heavy metals, lead, green basil

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563 Relationship of Trace Minerals Nutritional Status of Camel (Camelus dromedarius) to Their Contents in Egyptian Feedstuff

Authors: Maha Mohamed Hady Ali, M. A. El-Sayed

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Camel (Camelus dromedarius) is very important animal in many arid and semi-arid zones of tropical and subtropical regions as it serves as dual purpose providing meat and milk for human and as draft animal. Camel, like other animal must receive all essential nutrients despite the hostile environment. A study was conducted to evaluate the nutritional status of some micro-minerals of camel under Egyptian environmental condition. Forty five blood samples were collected from apparently healthy male camels with an average age between 2-6 years at the slaughter house in Cairo province, Egypt. The animals were fed mainly on berseem (Trifolium alexandrinum) or concentrate with straw before slaughtering. The collected serum and feedstuff samples were subjected to copper, iron, selenium and zinc analysis using Atomic absorption spectrophotometer. The data showed variation in the level of copper, iron, selenium and zinc in the serum of the dromedary camel as well as in the feedstuffs. Furthermore, the results indicated that the micro- minerals status of feeds may not always reflected as such in camel blood suggesting some role of bioavailability. The main reason for the lack of such reflection seems to be the wide diversity exists in the surrounding environment (forages and plants) as well as the bioavailability of such minerals. Since the requirement of micro-minerals have not been established for camel, more researches must be focused on this topic.

Keywords: camel, copper, egypt, feed stuff, iron, selenium, zinc

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562 Quantitative Structure-Activity Relationship Analysis of Binding Affinity of a Series of Anti-Prion Compounds to Human Prion Protein

Authors: Strahinja Kovačević, Sanja Podunavac-Kuzmanović, Lidija Jevrić, Milica Karadžić

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The present study is based on the quantitative structure-activity relationship (QSAR) analysis of eighteen compounds with anti-prion activity. The structures and anti-prion activities (expressed in response units, RU%) of the analyzed compounds are taken from CHEMBL database. In the first step of analysis 85 molecular descriptors were calculated and based on them the hierarchical cluster analysis (HCA) and principal component analysis (PCA) were carried out in order to detect potential significant similarities or dissimilarities among the studied compounds. The calculated molecular descriptors were physicochemical, lipophilicity and ADMET (absorption, distribution, metabolism, excretion and toxicity) descriptors. The first stage of the QSAR analysis was simple linear regression modeling. It resulted in one acceptable model that correlates Henry's law constant with RU% units. The obtained 2D-QSAR model was validated by cross-validation as an internal validation method. The validation procedure confirmed the model’s quality and therefore it can be used for prediction of anti-prion activity. The next stage of the analysis of anti-prion activity will include 3D-QSAR and molecular docking approaches in order to select the most promising compounds in treatment of prion diseases. These results are the part of the project No. 114-451-268/2016-02 financially supported by the Provincial Secretariat for Science and Technological Development of AP Vojvodina.

Keywords: anti-prion activity, chemometrics, molecular modeling, QSAR

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561 Estimation of Energy Efficiency of Blue Hydrogen Production Onboard of Ships

Authors: Li Chin Law, Epaminondas Mastorakos, Mohd Roslee Othman, Antonis Trakakis

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The paper introduces an alternative concept of carbon capture for shipping by using pre-combustion carbon capture technology (Pre-CCS), which was proven to be less energy intensive than post-combustion carbon capture from the engine exhaust. Energy assessment on amine-based post-combustion CCS on LNG-fuelled ships showed that the energy efficiency of CCS ships reduced from 48% to 36.6%. Then, an energy assessment was carried out to compare the power and heat requirements of the most used hydrogen production methods and carbon capture technologies. Steam methane reformer (SMR) was found to be 20% more energy efficient and achieved a higher methane conversion than auto thermal reaction and methane decomposition. Next, pressure swing adsorber (PSA) has shown a lower energy requirement than membrane separation, cryogenic separation, and amine absorption in pre-combustion carbon capture. Hence, an integrated system combining SMR and PSA (SMR-PSA) with waste heat integration (WHR) was proposed. This optimized SMR-based integrated system has achieved 65% of CO₂ reduction with less than 7-percentage point of energy penalty (41.7% of energy efficiency). Further integration of post-combustion CCS with the SMR-PSA integrated system improved carbon capture rate to 86.3% with 9-percentage points of energy penalty (39% energy efficiency). The proposed system was shown to be able to meet the carbon reduction targets set by International Maritime Organization (IMO) with certain energy penalties.

Keywords: shipping, decarbonisation, alternative fuels, low carbon, hydrogen, carbon capture

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560 Characterization and Nanostructure Formation of Banana Peels Nanosorbent with Its Application

Authors: Opeyemi Atiba-Oyewo, Maurice S. Onyango, Christian Wolkersdorfer

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Characterization and nanostructure formation of banana peels as sorbent material are described in this paper. The transformation of this agricultural waste via mechanical milling to enhance its properties such as changed in microstructure and surface area for water pollution control and other applications were studied. Mechanical milling was employed using planetary continuous milling machine with ethanol as a milling solvent and the samples were taken at time intervals between 10 h to 30 h to examine the structural changes. The samples were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red (FTIR), Transmission electron microscopy (TEM) and Brunauer Emmett and teller (BET). Results revealed three typical structures with different deformation mechanisms and the grain-sizes within the range of (71-12 nm), nanostructure of the particles and fibres. The particle size decreased from 65µm to 15 nm as the milling progressed for a period of 30 h. The morphological properties of the materials indicated that the particle shapes becomes regular and uniform as the milling progresses. Furthermore, particles fracturing resulted in surface area increment from 1.0694-4.5547 m2/g. The functional groups responsible for the banana peels capacity to coordinate and remove metal ions, such as the carboxylic and amine groups were identified at absorption bands of 1730 and 889 cm-1, respectively. However, the choice of this sorbent material for the sorption or any application will depend on the composition of the pollutant to be eradicated.

Keywords: characterization, nanostructure, nanosorbent, eco-friendly, banana peels, mechanical milling, water quality

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559 Water Diffusivity in Amorphous Epoxy Resins: An Autonomous Basin Climbing-Based Simulation Method

Authors: Betim Bahtiri, B. Arash, R. Rolfes

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Epoxy-based materials are frequently exposed to high-humidity environments in many engineering applications. As a result, their material properties would be degraded by water absorption. A full characterization of the material properties under hygrothermal conditions requires time- and cost-consuming experimental tests. To gain insights into the physics of diffusion mechanisms, atomistic simulations have been shown to be effective tools. Concerning the diffusion of water in polymers, spatial trajectories of water molecules are obtained from molecular dynamics (MD) simulations allowing the interpretation of diffusion pathways at the nanoscale in a polymer network. Conventional MD simulations of water diffusion in amorphous polymers lead to discrepancies at low temperatures due to the short timescales of the simulations. In the proposed model, this issue is solved by using a combined scheme of autonomous basin climbing (ABC) with kinetic Monte Carlo and reactive MD simulations to investigate the diffusivity of water molecules in epoxy resins across a wide range of temperatures. It is shown that the proposed simulation framework estimates kinetic properties of water diffusion in epoxy resins that are consistent with experimental observations and provide a predictive tool for investigating the diffusion of small molecules in other amorphous polymers.

Keywords: epoxy resins, water diffusion, autonomous basin climbing, kinetic Monte Carlo, reactive molecular dynamics

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558 Development of a Double Coating Technique for Recycled Concrete Aggregates Used in Hot-mix Asphalt

Authors: Abbaas I. Kareem, H. Nikraz

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The use of recycled concrete aggregates (RCAs) in hot-mix asphalt (HMA) production could ease natural aggregate shortage and maintain sustainability in modern societies. However, it was the attached cement mortar and other impurities that make the RCAs behave differently than high-quality aggregates. Therefore, different upgrading treatments were suggested to enhance its properties before being used in HMA production. Disappointedly, some of these treatments had caused degradation to some RCA properties. In order to avoid degradation, a coating technique is developed. This technique is based on combining of two main treatments, so it is named as double coating technique (DCT). Dosages of 0%, 20%, 40% and 60% uncoated RCA, RCA coated with Cement Slag Paste (CSP), and Double Coated Recycled Concrete Aggregates (DCRCAs) in place of granite aggregates were evaluated. The results indicated that the DCT improves strength and reduces water absorption of the DCRCAs compared with uncoated RCAs and RCA coated with CSP. In addition, the DCRCA asphalt mixtures exhibit stability values higher than those obtained for mixes made with granite aggregates, uncoated RCAs and RCAs coated with CSP. Also, the DCRCA asphalt mixtures require less bitumen to achieve the optimum bitumen content (OBC) than those manufactured with uncoated RCA and RCA-coated with CSP. Although the results obtained were encouraging, more testing is required in order to examine the effect of the DCT on performance properties of DCRCA- asphalt mixtures such as rutting and fatigue.

Keywords: aggregate crashed value, double coating technique, hot mix asphalt, Marshall parameters, recycled concrete aggregates

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557 Development and Characterization of Soya Phosphatidylcholine Complex of Coumestans from Eclipta alba for the Management of Hepatotoxicity

Authors: Abhishek Kumar Jain, Anki Jain, Yuvraj Singh Dangi, Brajesh Kumar Tiwari

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The plant Eclipta alba Hassk. (Family: Compositae) contains coumestans (wedelolactone and demethyl wedelolactone) used in liver disorders. The objective of the present investigation was to develop a formulation of these coumestans in combination with the soya phosphatidylcholine (PC), in order to overcome the limitation of absorption and to investigate the protective effect of coumestans–phosphatidylcholine complex (C-PC) on carbon tetrachloride induced acute liver damage in rats. Methanolic extract (ME) of the whole plant of Eclipta alba was fractionated with water and then with ehylacetate. Coumestans were characterized in the ethylacetate fraction of methanolic extract (EFME). The C-PC was prepared by dissolving EFME and PC in 1:1 ratio in dichloromethane and heating at 60°C for 2 h. The C-PC was characterized by DSC and FTIR spectroscopy. In vitro drug release from EFME and C-PC through egg membrane was measured using UV-Visible spectrophotometer. The hepatoprotective activity of C-PC (equivalent to 5.35 and 10.7 mg/kg body weight of EFME), ME 250 mg/kg and EFME 5.35 mg/kg was evaluated by measuring various enzymes level. C-PC significantly provided better protection to the liver by restoring the enzyme levels of SGPT, SGOT, ALP and total billirubin with respect to carbon tetrachloride (CCl4) treated group (P < 0.001). Histopathological studies were also performed. The C-PC provided better protection to rat liver than ME and EFME at similar doses as well as shown significant regeneration of hepatocytes, central vein, intact cytoplasm, and nucleus.

Keywords: hepatotoxicity, wedelolactone, soya phosphatidylcholine, eclipta alba

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556 Synthesis, Characterization and Antibacterial Activity of Metalloporphyrins: Role of Central Metal Ion

Authors: Belete B. Beyene, Ayenew M. Mihirteu, Misganaw T. Ayana, Amogne W. Yibeltal

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Modification of synthetic porphyrins is one of the promising strategies in an attempt to get molecules with desired properties and applications. Here in, we report synthesis, photophysical characterization and antibacterial activity of 5, 10, 15, 20-tetrakis-(4- methoxy carbonyl phenyl) porphyrin M(II); where M = Co, Fe, Ni, Zn. Metallation of the ligand was confirmed by using UV–Vis spectroscopy and ESI-Ms measurement, in which the number of Q bands in absorption spectra of the ligand decreased from four to one or two as a result of metal insertion to the porphyrin core. The antibacterial activity study of the complexes toward two Gram-positive (Staphylococcus aureus (S. aureus) and Streptococcus pyogenes (s. pyogenes)) and two Gram-negative (Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae)) bacteria by disc diffusion method showed a promising inhibitory activity. The complexes exhibited highest activities at highest concentration and were better than the activity of free base ligand, the salts, and blank solution. This could be explained on the basis of Overton's concept of cell permeability and Tweed's Chelation theory. An increased lipo-solubility enhances the penetration of the complexes into the lipid membrane and interferes with the normal activities of the bacteria. Our study, therefore, showed that the growth inhibitory effect of these metalloporphyrins is generally in order of ZnTPPCOOMe > NiTPPCOOMe > CoTPPCOOMe> FeTPPCOOMe, which may be attributed to the better lipophilicity and binding of the complex with the cellular components.

Keywords: porphyrins, metalloporphyrins, spectral property, antibacterial activity, synthesis

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555 Cd1−xMnxSe Thin Films Preparation by Cbd: Aspect on Optical and Electrical Properties

Authors: Jaiprakash Dargad

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CdMnSe dilute semiconductor or semimagnetic semiconductors have become the focus of intense research due to their interesting combination of magnetic and semiconducting properties, and are employed in a variety of devices including solar cells, gas sensors etc. A series of thin films of this material, Cd1−xMnxSe (0 ≤ x ≤ 0.5), were therefore synthesized onto precleaned amorphous glass substrates using a solution growth technique. The sources of cadmium (Cd2+) and manganese (Mn2+) were aqueous solutions of cadmium sulphate and manganese sulphate, and selenium (Se2−) was extracted from a reflux of sodium selenosulphite. The different deposition parameters such as temperature, time of deposition, speed of mechanical churning, pH of the reaction mixture etc were optimized to yield good quality deposits. The as-grown samples were thin, relatively uniform, smooth and tightly adherent to the substrate support. The colour of the deposits changed from deep red-orange to yellowish-orange as the composition parameter, x, was varied from 0 to 0.5. The terminal layer thickness decreased with increasing value of, x. The optical energy gap decreased from 1.84 eV to 1.34 eV for the change of x from 0 to 0.5. The coefficient of optical absorption is of the order of 10-4 - 10-5 cm−1 and the type of transition (m = 0.5) is of the band-to-band direct type. The dc electrical conductivities were measured at room temperature and in the temperature range 300 K - 500 K. It was observed that the room temperature electrical conductivity increased with the composition parameter x up to 0.1, gradually decreasing thereafter. The thermo power measurements showed n-type conduction in these films.

Keywords: dilute semiconductor, reflux, CBD, thin film

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554 Testing Ammonia Borane for Multilayer Aprons in Nuclear Medicine as a Promising Non-toxic, Lightweight, Hydrogen Rich Material and to Enhance the Efficiency of Aprons for Workers Who Deal with Neutrons Radiation in Nuclear Medicine

Authors: Wed Othman Alghamdi

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The current study aims to find a non-toxic, low density, hydrogen-rich material that can be used in aprons without causing health issues for nuclear medical workers that could hinder their work and negatively affect patients. Five samples were tested in terms of fast neutron removal cross-section(C21H25ClO5, C2H4, LiH,H3NBH3,MgH2) mathematically using computer program called Phy-x/PSD it is a computer program designed to calculate the fast neutron removal cross section, and it was obtained that ammonia borane (𝐻3𝑁𝐵𝐻3) with a density of 0.78 (g/ cm3) ,And it containment of the three most important elements that play a major role in protection shields, which are (hydrogen, boron, nitrogen), Hydrogen works as a moderator that slows neutrons and turn them into thermal neutrons, boron and nitrogen both have the largest neutron absorption cross section. Ammonia borane has the highest fast neutron removal cross-section with the value of (0.122959317985393cm-1) and the least for polyethylene (𝐶2𝐻4) with the value of (0.0838038707225853 cm-1) which made the ammonia borane a better candidate than polyethylene and other compounds that have been tasted in previous research for multi-layer aprons in nuclear medicine, and may approve a proper protection against the hazard radiations that its produced in nuclear medicine filed by several ways, due to it is low density and non-toxicity.

Keywords: aprons, radiation, non-toxic, nuclear medicine, neutrons

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553 Tribological Response of Self-Mated Zircaloy-4 under Varying Conditions

Authors: Bharat Kumar, Deepak Kumar, Vijay Chaudhry

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Zirconium alloys are widely used for the core components of a pressurized heavy water reactor (PHWR) or Canada deuterium (CANDU) reactor due to their low neutron absorption cross-section and excellent mechanical properties. The components made of Zirconium alloys are subjected to flow-induced vibrations, resulting in fretting wear at the interface of; pressure tubes and bearing pads, pressure tubes and calandria tubes, and calandria tubes and Liquid injection shutdown system (LISS) nozzles. There is a need to explore the tribological response under such conditions. Present work simulates the contact between calandria tube and LISS nozzle of PHWR/CANDU reactor as cylinder-on-cylinder contact configuration. Reciprocating tribo-tests were conducted on Zircaloy-4 (Zr-4) under the self-mated condition at varying amplitude, frequency, and sliding time. To understand the active wear mechanism, worn surfaces were analyzed using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The change in amplitude severely affects the wear than other factors. The wear mechanism transits from adhesion to abrasion with increasing test amplitude. The dominant wear mechanisms are micro-cutting and micro-plowing followed by delamination in some areas. However, the coefficient of friction has indifferent behaviors.

Keywords: zircaloy-4, tribology, calandria tube, LISS nozzle, PHWR

Procedia PDF Downloads 183
552 Thiazolo[5,4-D]Thiazole-Core Organic Chromophore with Furan Spacer for Organic Solar Cells

Authors: M. Nazim, S. Ameen, H. K. Seo, H. S. Shin

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Energy is the basis of life and strong attention has been growing for the cost-effective energy production. Recently, solution-processed small molecule organic solar cells (SMOSCs) have grown much attention due to the wages such as well-defined molecular structures, definite molecular weight, easy synthesis and easy purification techniques. In particular, the size of donor (D) and acceptor (A) unit is a crucial factor for the exciton-diffusion towards D-A interface and then charge-separation for the effective charge-transport to the electrodes. Furan-bridged materials are more electron-rich, high fluorescence, with better molecular-packing, and greater rigidity and greater solubility than their thiophene-counterparts In this work, a furan-bridged thiazolo[5,4-d]thiazole based organic small molecule (RFTzR) was formulated and applied for BHJ organic solar cells (OSCs). The introduction of furan spacer with two terminal alkyl units improved its absorption and solubility in the common organic solvents, significantly. RFTzR exhibited a HOMO and LUMO energy levels of -5.36 eV and -3.14 eV, respectively. The fabricated solar cell devices of RFTzR (donor) with PC60BM (acceptor) as photoactive materials showed high performance of 2.72% (RFTzR:PC60BM, 2:1, w/w) ratio with open-circuit voltage of 0.756 V and high photocurrent density of 10.13 mA/cm².

Keywords: chromophore, organic solar cells, photoactive materials, small molecule

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551 Recycled Aggregates from Construction and Demolition Waste in the Production of Concrete Blocks

Authors: Juan A. Ferriz-Papi, Simon Thomas

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The construction industry generates large amounts of waste, usually mixed, which can be composed of different origin materials, most of them catalogued as non-hazardous. The European Union targets for this waste for 2020 have been already achieved by the UK, but it is mainly developed in downcycling processes (backfilling) whereas upcycling (such as recycle in new concrete batches) still keeps at a low percentage. The aim of this paper is to explore further in the use of recycled aggregates from construction and demolition waste (CDW) in concrete mixes so as to improve upcycling. A review of most recent research and legislation applied in the UK is developed regarding the production of concrete blocks. As a case study, initial tests were developed with a CDW recycled aggregate sample from a CDW plant in Swansea. Composition by visual inspection and sieving tests of two samples were developed and compared to original aggregates. More than 70% was formed by soil waste from excavation, and the rest was a mix of waste from mortar, concrete, and ceramics with small traces of plaster, glass and organic matter. Two concrete mixes were made with 80% replacement of recycled aggregates and different water/cement ratio. Tests were carried out for slump, absorption, density and compression strength. The results were compared to a reference sample and showed a substantial reduction of quality in both mixes. Despite that, the discussion brings to identify different aspects to solve, such as heterogeneity or composition, and analyze them for the successful use of these recycled aggregates in the production of concrete blocks. The conclusions obtained can help increase upcycling processes ratio with mixed CDW as recycled aggregates in concrete mixes.

Keywords: aggregates, concrete, concrete block, construction and demolition waste, recycling

Procedia PDF Downloads 279
550 Effect of Brewing on the Bioactive Compounds of Coffee

Authors: Ceyda Dadali, Yeşim Elmaci

Abstract:

Coffee was introduced as an economic crop during the fifteenth century; nowadays it is the most important food commodity ranking second after crude oil. Desirable sensory properties make coffee one of the most often consumed and most popular beverages in the world. The coffee preparation method has a significant effect on flavor and composition of coffee brews. Three different extraction methodologies namely decoction, infusion and pressure methods have been used for coffee brew preparation. Each of these methods is related to specific granulation (coffee grind) of coffee powder, water-coffee ratio temperature and brewing time. Coffee is a mixture of 1500 chemical compounds. Chemical composition of coffee highly depends on brewing methods, coffee bean species and roasting time-temperature. Coffee contains a wide number of very important bioactive compounds, such as diterpenes: cafestol and kahweol, alkaloids: caffeine, theobromine and trigonelline, melanoidins, phenolic compounds. The phenolic compounds of coffee include chlorogenic acids (quinyl esters of hidroxycinnamic acids), caffeic, ferulic, p-coumaric acid. In coffee caffeoylquinic acids, feruloylquinic acids and di-caffeoylquinic acids are three main groups of chlorogenic acids constitues 6% -10% of dry weight of coffee. The bioavailability of chlorogenic acids in coffee depends on the absorption and metabolization to biomarkers in individuals. Also, the interaction of coffee polyphenols with other compounds such as dietary proteins affects the biomarkers. Since bioactive composition of coffee depends on brewing methods effect of coffee brewing method on bioactive compounds of coffee will be discussed in this study.

Keywords: bioactive compounds of coffee, biomarkers, coffee brew, effect of brewing

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549 Synthesis of Plant-Mediated Silver Nanoparticles Using Erythrina indica Extract and Evaluation of Their Anti-Microbial Activities

Authors: Chandra Sekhar Singh, P. Chakrapani, B. Arun Jyothi, A. Roja Rani

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The green synthesis of metallic nanoparticles (NPs) involves biocompatible ingredients under physiological conditions of temperature and pressure. Moreover, the biologically active molecules involved in the green synthesis of NPs act as functionalizing ligands, making these NPs more suitable for biomedical applications. Among the most important bioreductants are plant extracts, which are relatively easy to handle, readily available, low cost, and have been well explored for the green synthesis of other nanomaterials. Various types of metallic NPs have already been synthesized using plant extracts. They have wide applicability in various areas such as electronics, catalysis, chemistry, energy, and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In our study, we were described a cost effective and environment friendly technique for green synthesis of silver nanoparticles from 1mM AgNO3 solution through the aqueous extract of Erythrina indica as reducing as well as capping agent. Nanoparticles were characterized using UV–Vis absorption spectroscopy, FTIR, XRD, X-ray diffraction, SEM and TEM analysis showed the average particle size of 30 nm as well as revealed their spherical structure. Further these biologically synthesized nanoparticles were found to be highly toxic against different human pathogens viz. two Gram positive namely Klebsiella pneumonia and Bacillus subtilis bacteria and two were Gram negative bacteria namely Staphylococcus aureus and Escherichia coli (E. coli). This is for the first time reporting that Erythrina indica plant extract was used for the synthesis of nanoparticles.

Keywords: silver nanoparticles, green synthesis, antibacterial activity, FTIR, TEM, SEM

Procedia PDF Downloads 477
548 On Compression Properties of Honeycomb Structures Using Flax/PLA Composite as Core Material

Authors: S. Alsubari, M. Y. M. Zuhri, S. M. Sapuan, M. R. Ishaks

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Sandwich structures based on cellular cores are increasingly being utilized as energy-absorbing components in the industry. However, determining ideal structural configurations remains challenging. This chapter compares the compression properties of flax fiber-reinforced polylactic acid (PLA) of empty honeycomb core, foam-filled honeycomb and double cell wall square interlocking core sandwich structure under quasi-static compression loading. The square interlocking core is fabricated through a slotting technique, whereas the honeycomb core is made using a corrugated mold that was initially used to create the corrugated core composite profile, which is then cut into corrugated webs and assembled to form the honeycomb core. The sandwich structures are tested at a crosshead displacement rate of 2 mm/min. The experimental results showed that honeycomb outperformed the square interlocking core in terms of their strength capability and SEA by around 14% and 34%, respectively. It is observed that the foam-filled honeycomb collapse in a progressive mode, exhibiting noticeable advantages over the empty honeycomb; this is attributed to the interaction between the honeycomb wall and foam filler. Interestingly, the average SEAs of foam-filled and empty honeycomb cores have no significant difference, around 8.7kJ/kg and 8.2kJ/kg, respectively. In contrast, its strength capability is clearly pronounced, in which the foam-filled core outperforms the empty counterparts by around 33%. Finally, the results for empty and foam-filled cores were significantly superior to aluminum cores published in the literature.

Keywords: compressive strength, flax, honeycomb core, specific energy absorption

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547 The Collagen and Glycosaminoglycnas Isolated from Salmo Salar Skin

Authors: Beata Kaczmarek-Szczepańska, Lidia Zasada

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Marine collagens such as fish skin, bone, cartilage, and scales, including both marine vertebrates and invertebrates sources, are more bioavailable compared to bovine or porcine collagen and have a higher absorption capability and more rapid bloodstream circulation due to their low molecular weight and small particle size. Fish skin may be used as a source of bioactive compounds. The advantage is that fish skin is a by-product of the food industry. The subject of the study is a lyophilizate consisting of a mixture of compounds from the group of glycosaminoglycans and collagen obtained as a result of processing fish skins. Bioactive compounds may find biomedical use in the production of dressing materials for wounds or in tissue engineering for the production of scaffolds for cells. Collagen and glycosaminoglycans were isolated from Salmo salar skin. The final mixture was obtained by the freeze-drying method. In the obtained lyophilizate, the content of amino acids was studied as well as the presence of polysaccharides. The studies showed the presence of glycine, proline, and hydroxyproline, which are the main amino acids of collagen. The HPLC analysis showed the presence of glucose which is a product of polysaccharides hydrolyzation and then reduction of glucuronic acid. It may be assumed that the lyophilizate contains both collagen and polysaccharide, which is probably hyaluronic acid. Acknowledgment: This work was carried out as a result of research project no. TANGO-V-A/0020/2021 financed by the National Centre for Research and Development.

Keywords: collagen, glycosaminoglycans, bioactive compounds, fish skin

Procedia PDF Downloads 92