Search results for: fatty acid methyl esters

Authors: Juraj Beniak, Ľubomír Šooš, Peter Križan, Miloš Matúš

Abstract:

Within Rapid Prototyping technologies are used many types of materials. Many of them are recyclable but there are still as plastic like, so practically they do not degrade in the landfill. Polylactic acid (PLA) is one of the special plastic materials which are biodegradable and also available for 3D printing within Fused Deposition Modelling (FDM) technology. The question is, if the mechanical properties of produced models are comparable to similar technical plastic materials which are usual for prototype production. Presented paper shows the experiments results for tensile strength measurements for specimens prepared with different 3D printer settings and model orientation. Paper contains also the comparison of tensile strength values with values measured on specimens produced by conventional technologies as injection moulding.

Keywords: 3D printing, biodegradable plastic, fused deposition modeling, PLA plastic, rapid prototyping

Procedia PDF Downloads 416

Authors: António Fiúza, Aurora Futuro, Joana Monteiro, Joaquim Góis

Abstract:

Lepidolite is an important lithium mineral that, to the author’s best knowledge, has not been used to produce lithium hydroxide, which is necessary for energy conversion to electric vehicles. Alkaline leaching of lithium concentrates allows the establishment of a production diagram avoiding most of the environmental drawbacks that are associated with the usage of acid reagents. The tested processes involve a pretreatment by digestion at high temperatures with additives, followed by leaching at hot atmospheric pressure. The solutions obtained must be compatible with solutions from the leaching of spodumene concentrates, allowing the development of a common treatment diagram, an important accomplishment for the feasible exploitation of Portuguese resources. Statistical programming and interpretation techniques minimize the laboratory effort required by conventional approaches and allow phenomenological comprehension.

Keywords: alkaline leaching, lithium, research design, statistical interpretation

Procedia PDF Downloads 97

Authors: Siming Wang, Qing Ni, Yu Wu, Ruihai Xu, Hong Ye

Abstract:

Porous electric heaters, compared to conventional electric heaters, exhibit excellent heating performance due to their large specific surface area. Porous electric heaters employ porous metallic materials or conductive porous ceramics as the heating element. The former attains a low heating power with a fixed current due to the low electrical resistivity of metal. Although the latter can bypass the inherent challenges of porous metallic materials, the fabrication process of the conductive porous ceramics is complicated and high cost. This work proposed a porous ceramic electric heater with dielectric honeycomb ceramic as a substrate and surface conductive coating as a heating element. The conductive coating was prepared by the sol-gel method using silica sol and methyl trimethoxysilane as raw materials and graphite powder as conductive fillers. The conductive mechanism and degradation reason of the conductive coating was studied by electrical resistivity and thermal stability analysis. The heating performance of the proposed heater was experimentally investigated by heating air and deionized water. The results indicate that the electron transfer is achieved by forming the conductive network through the contact of the graphite flakes. With 30 wt% of graphite, the electrical resistivity of the conductive coating can be as low as 0.88 Ω∙cm. The conductive coating exhibits good electrical stability up to 500°C but degrades beyond 600°C due to the formation of many cracks in the coating caused by the weight loss and thermal expansion. The results also show that the working medium has a great influence on the volume power density of the heater. With air under natural convection as the working medium, the volume power density attains 640.85 kW/m3, which can be increased by 5 times when using deionized water as the working medium. The proposed honeycomb ceramic electric heater has the advantages of the simple fabrication method, low cost, and high volume power density, demonstrating great potential in the fluid heating field.

Keywords: conductive coating, honeycomb ceramic electric heater, high specific surface area, high volume power density

Procedia PDF Downloads 153

Authors: Hateem Zafar Kayani, Nageen Hussain

Abstract:

The main aim is to analyze the mutations of DNASE I gene in diabetic patients. A total of 120 diabetes patients and 120 controls were sampled. The total number of male diabetic patients included in the study was 79 (66%) while female patients were 41 (34%) in number. Exon 8 of the DNASE I gene was amplified by using thermo cycler. The possible band of interest was located at 165 base pairs. Two samples showed similar missense mutations at 127th position of exon 8 which replaced amino acid Arginine (Arg) to Glutamine (Gln). All controls showed no mutations. The association of diabetes with different levels of blood pressure and body mass index (BMI) were found to be significant.

Keywords: deoxyribonuclease I, polymerase chain reaction, insulin-dependent diabetes mellitus, non-insulin dependent diabetes mellitus

Procedia PDF Downloads 325

Authors: Momita Das, Sofia Banu, Jibon Kotoky

Abstract:

Environmental contamination of natural resources with persistent organic pollutants is of great world-wide apprehension. Polycyclic aromatic hydrocarbons (PAHs) are among the organic pollutants, released due to various anthropogenic activities. Due to their toxic, carcinogenic and mutagenic properties, PAHs are of environmental and human concern. Presently, bioremediation has evolved as the most promising biotechnology for cleanup of such contaminants because of its economical and less cost effectiveness. In the present study, distribution of 16 USEPA priority PAHs was determined in the soil samples collected from fifteen different sites of Guwahati City, the Gateway of the North East Region of India. The total concentrations of 16 PAHs (Σ16 PAHs) ranged from 42.7-742.3 µg/g. Higher concentration of total PAHs was found more in the Industrial areas compared to all the sites (742.3 µg/g and 628 µg/g). It is noted that among all the PAHs, Naphthalene, Acenaphthylene, Anthracene, Fluoranthene, Chrysene and Benzo(a)Pyrene were the most available and contain the higher concentration of all the PAHs. Since microbial activity has been deemed the most influential and significant cause of PAH removal; further, twenty-three bacteria were isolated from the most contaminated sites using the enrichment process. These strains were acclimatized to utilize naphthalene and anthracene, each at 100 µg/g concentration as sole carbon source. Among them, one Gram-positive strain (JMG-01) was selected, and biodegradation ability and initial catabolic genes of PAHs degradation were investigated. Based on 16S rDNA analysis, the isolate was identified as Bacillus cereus strain JMG-01. Topographic images obtained using Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) at scheduled time intervals of 7, 14 and 21 days, determined the variation in cell morphology during the period of degradation. AFM and SEM micrograph of biomass showed high filamentous growth leading to aggregation of cells in the form of biofilm with reference to the incubation period. The percentage degradation analysis using gas chromatography and mass analyses (GC-MS) suggested that more than 95% of the PAHs degraded when the concentration was at 500 µg/g. Naphthalene, naphthalene-2-methy, benzaldehyde-4-propyl, 1, 2, benzene di-carboxylic acid and benzene acetic acid were the major metabolites produced after degradation. Moreover, PCR experiments with specific primers for catabolic genes, ndo B and Cat A suggested that JMG-01 possess genes for PAHs degradation. Thus, the study concludes that Bacillus cereus strain JMG-01 has efficient biodegrading ability and can trigger the clean-up of PAHs contaminated soil.

Keywords: AFM, Bacillus cereus strain JMG-01, degradation, polycyclic aromatic hydrocarbon, SEM

Procedia PDF Downloads 276

Authors: Seyyed Mohammad Amin Mousavi Sagharchi, Elham Javanroudi

Abstract:

Introduction: Tuberculosis (TB) is a known disease with hidden features caused by Mycobacterium tuberculosis (MTB). This disease, which is one of the 10 deadliest in the world, has caused millions of deaths in recent decades. Furthermore, TB is responsible for infecting about 30% population of world. Like any infection, TB can activate the immune system by locating and colonization in the human body, especially in the alveoli. TB is granulomatosis, so MTB can absorb the host’s immune cells and other cells to form granuloma. Method: Different databases (e.g., PubMed) were recruited to prepare this paper and fulfill our goals to search and find effective papers and investigations. Results: Immune response to MTB is related to T cell killers and contains CD1, CD4, and CD8 T lymphocytes. CD1 lymphocytes can recognize glycolipids, which highly exist in the Mycobacterial fatty cell wall. CD4 lymphocytes and macrophages form granuloma, and it is the main line of immune response to Mycobacteria. On the other hand, CD8 cells have cytolytic function for directly killing MTB by secretion of granulysin. Other functions and secretion to the deal are interleukin-12 (IL-12) by induction of expression interferon-γ (INF-γ) for macrophages activation and creating a granuloma, and tumor necrosis factor (TNF) by promoting macrophage phagolysosomal fusion. Conclusion: Immune cells in battle with MTB are macrophages, dendritic cells (DCs), neutrophils, and natural killer (NK) cells. These immune cells can recognize the Mycobacterium by various receptors, including Toll-like receptors (TLRs), Nod-like receptors (NLRs), and C-type lectin receptors (CLRs) located in the cell surface. In human alveoli exist about 50 dendritic macrophages, which have close communication with other immune cells in the circulating system and epithelial cells to deal with Mycobacteria. Against immune cells, MTB handles some factors (e.g., cordfactor, O-Ag, lipoarabinomannan, sulfatides, and adenylate cyclase) and practical functions (e.g., inhibition of macrophages).

Keywords: mycobacterium tuberculosis, immune responses, immunological mechanisms, respiratory tuberculosis

Procedia PDF Downloads 109

Authors: Sabolč Pap, Srđana Kolaković, Jelena Radonić, Ivana Mihajlović, Dragan Adamović, Mirjana Vojinović Miloradov, Maja Turk Sekulić

Abstract:

Activated carbon is one of the most used and tested adsorbents in the removal of industrial organic compounds, heavy metals, pharmaceuticals and dyes. Different types of lignocellulosic materials were used as potential precursors in the production of low cost activated carbon. There are, two different processes for the preparation and production of activated carbon: physical and chemical. Chemical activation includes impregnating the lignocellulosic raw materials with chemical agents (H3PO4, HNO3, H2SO4 and NaOH). After impregnation, the materials are carbonized and washed to eliminate the residues. The chemical activation, which was used in this study, has two important advantages when compared to the physical activation. The first advantage is the lower temperature at which the process is conducted, and the second is that the yield (mass efficiency of activation) of the chemical activation tends to be greater. Preparation of activated carbon included the following steps: apricot stones were crushed in a mill and washed with distilled water. Later, the fruit stones were impregnated with a solution of 50% H3PO4. After impregnation, the solution was filtered to remove the residual acid. Subsequently impregnated samples were air dried at room temperature. The samples were placed in a furnace and heated (10 °C/min) to the final carbonization temperature of 500 °C for 2 h without the use of nitrogen. After cooling, the adsorbent was washed with distilled water to achieve acid free conditions and its pH was monitored until the filtrate pH value exceeded 4. Chemical characterizations of the prepared activated carbon were analyzed by FTIR spectroscopy. FTIR spectra were recorded with a (Thermo Nicolet Nexus 670 FTIR) spectrometer, from 400 to 4000 cm-1 wavenumbers, identifying the functional groups on the surface of the activated carbon. The FTIR spectra of adsorbent showed a broad band at 3405.91 cm-1 due to O–H stretching vibration and a peak at 489.00 cm-1 due to O–H bending vibration. Peaks between the range of 3700 and 3200 cm−1 represent the overlapping peaks of stretching vibrations of O–H and N–H groups. The distinct absorption peaks at 2919.86 cm−1 and 2848.24 cm−1 could be assigned to -CH stretching vibrations of –CH2 and –CH3 functional groups. The adsorption peak at 1566.38 cm−1 could be characterized by primary and secondary amide bands. The sharp bond within 1164.76 – 987.86 cm−1 is attributed to the C–O groups, which confirms the lignin structure of the activated carbon. The present study has shown that the activated carbons prepared from apricot stone have a functional group on their surface, which can positively affect the adsorption characteristics with this material.

Keywords: activated carbon, FTIR, H3PO4, lignocellulosic raw materials

Procedia PDF Downloads 250

Authors: Martina Grdiša, Filip Varga, Nina Jeran, Ante Turudić, Zlatko Šatović

Abstract:

Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.) is a plant species that occurs naturally in the eastern Mediterranean. It is of immense economic importance as it synthesizes and accumulates the phytochemical compound pyrethrin. Pyrethrin consists of several monoterpene esters (pyrethrin I and II, cinerin I and II and jasmolin I and II), which have insecticidal and repellent activity through their synergistic action. In this study, 15 natural Dalmatian pyrethrum populations were sampled along their natural range in Croatia, Bosnia and Herzegovina and Montenegro to characterize and compare their pyrethrin profiles and to define the bioclimatic factors associated with the accumulation of each pyrethrin compound. Pyrethrins were extracted from the dried flower heads of Dalmatian pyrethrum using ultrasound-assisted extraction and the amount of each compound was quantified using high-performance liquid chromatography coupled to DAD-UV /VIS. The biochemical data were subjected to analysis of variance, correlation analysis and multivariate analysis. Quantitative variability within and among populations was found, with population P15 Vranjske Njive, Podgorica having the significantly highest pyrethrin I content (66.47% of total pyrethrin content), while the highest levels of total pyrethrin were found in P14 Budva (1.27% of dry flower weight; DW), followed by P08 Korčula (1.15% DW). Based on the environmental conditions at the sampling sites of the populations, five bioclimatic groups were distinguished, referred to as A, B, C, D, and E, each with rare chemical profile. The first group (A) consisted of the northern Adriatic population P01 Vrbnik, Krk and the population P06 Sevid - the coastal population of the central Adriatic, and generally differed significantly from the other bioclimatic groups by higher average jasmolin II values (2.13% of total pyrethrin). The second group (B) consisted of two central Adriatic island populations (P02 Telašćica, Dugi otok and P03 Žman, Dugi otok), while the remaining central Adriatic island populations were grouped in bioclimatic group C, which was characterized by the significantly highest average pyrethrin II (48.52% of total pyrethrin) and cinerin II (5.31% DW) content. The South Adriatic inland populations P10 Srđ and P11 Trebinje (Bosnia and Herzegovina), and the populations from Montenegro (P12 Grahovo, P13 Lovćen, P14 Budva and P15 Vranjske Njive, Podgorica) formed bioclimatic group E. This bioclimatic group was characterized by the highest average values for pyrethrin I (53.07 % of total pyrethrin), total pyrethrin content (1.06 % DW) and the ratio of pyrethrin I and II (1.85). Slightly lower values (although not significant) for the latter traits were detected in bioclimatic group D (southern Adriatic island populations P07 Vis, P08 Korčula and P09 Mljet). A weak but significant correlation was found between the levels of some pyrethrin compounds and bioclimatic variables (e.g., BIO03 Isothermality and BIO04 Temperature Seasonality), which explains part of the variability observed in the populations studied. This suggests the interconnection between bioclimatic variables and biochemical profiles either through the selection of adapted genotypes or through the ability of species to alter the expression of biochemical traits in response to environmental changes.

Keywords: biopesticides, biochemical variability, pyrethrin, Tanacetum cinerariifolium

Procedia PDF Downloads 155

Authors: Moetazza M. Alshafei, Ahmed M. Mabrouk, Emtenan M. Hanafi, Manal M. Ramadan, Reda M. S. Korany, Seham S. Kassem, Dina Mostafa Mohammed

Abstract:

Metabolic syndrome (MeS) is a major health problem with a high incidence of obese individuals worldwide. Increased related morbidity of diabetes, hypertension and fatty liver disease, and complicated cardiovascular disease are inevitable. Boswellia serrata gum (Bos) is a promising traditional medicinal plant; it has several pharmacological properties, including anti-inflammatory, antioxidant, and antilipase activities. Probiotics (Bac) supplements have good benefits on health and MeS, whether it is supplemented in combination with prebiotics or alone. Microencapsulation helps to mask unpalatable taste and odor and deliver active ingredients to targeted organs. Methodology MeS rat model was produced by feeding rats with a high fat, high CHO diet (HFD). Bos was extracted, and both Bos and the probiotic were microencapsulated with a spray drier. Female rats were divided into 5 groups (N8). HFD control, control normal receiving basic diet, HFD treated, from the start of the experiment, either with encapsulated Bos, Bac and Bos or Bac only, all treatments were received for eight weeks (after approval from NRC animal ethical committee). Serum was collected to analyze lipid profile, blood sugar, liver and kidney functions, antioxidants, leptin, and progesterone. Rat's organs and body fat were weighed and collected for histopathology. Statistical analysis was done by use of one way Anova test in the SPSS program. Results showed control of elevated body weight, lipid profile, and glucose levels as well as decrease of body fat index and improvement of histopathology of liver and heart, especially in combination. Conclusion: We concluded that both microencapsulated Bos and probiotics have a controlling effect on MeS parameters.

Keywords: metabolic syndrome, Boswellia serata, probiotic, micro-encapsulation, histopathology, liver steatosis

Procedia PDF Downloads 102

Authors: Rajeev Ravindran, Amit K. Jaiswal

Abstract:

Lignocellulose is the largest reservoir of inexpensive, renewable source of carbon. It is composed of lignin, cellulose and hemicellulose. Cellulose and hemicellulose is composed of reducing sugars glucose, xylose and several other monosaccharides which can be metabolised by microorganisms to produce several value added products such as biofuels, enzymes, aminoacids etc. Enzymatic treatment of lignocellulose leads to the release of monosaccharides such as glucose and xylose. However, factors such as the presence of lignin, crystalline cellulose, acetyl groups, pectin etc. contributes to recalcitrance restricting the effective enzymatic hydrolysis of cellulose and hemicellulose. In order to overcome these problems, pre-treatment of lignocellulose is generally carried out which essentially facilitate better degradation of lignocellulose. A range of pre-treatment strategy is commonly employed based on its mode of action viz. physical, chemical, biological and physico-chemical. However, existing pretreatment strategies result in lower sugar yield and formation of inhibitory compounds. In order to overcome these problems, we proposes a novel pre-treatment, which utilises the superior oxidising capacity of alkaline potassium permanganate assisted by ultra-sonication to break the covalent bonds in spent coffee waste to remove recalcitrant compounds such as lignin. The pre-treatment was conducted for 30 minutes using 2% (w/v) potassium permanganate at room temperature with solid to liquid ratio of 1:10. The pre-treated spent coffee waste (SCW) was subjected to enzymatic hydrolysis using enzymes cellulase and hemicellulase. Shake flask experiments were conducted with a working volume of 50mL buffer containing 1% substrate. The results showed that the novel pre-treatment strategy yielded 7 g/L of reducing sugar as compared to 3.71 g/L obtained from biomass that had undergone dilute acid hydrolysis after 24 hours. From the results obtained it is fairly certain that ultrasonication assists the oxidation of recalcitrant components in lignocellulose by potassium permanganate. Enzyme hydrolysis studies suggest that ultrasound assisted alkaline potassium permanganate pre-treatment is far superior over treatment by dilute acid. Furthermore, SEM, XRD and FTIR were carried out to analyse the effect of the new pre-treatment strategy on structure and crystallinity of pre-treated spent coffee wastes. This novel one-step pre-treatment strategy was implemented under mild conditions and exhibited high efficiency in the enzymatic hydrolysis of spent coffee waste. Further study and scale up is in progress in order to realise future industrial applications.

Keywords: spent coffee waste, alkaline potassium permanganate, ultra-sonication, physical characterisation

Procedia PDF Downloads 357

Authors: Mohammadreza Biabani, Mohammad Azadfallah

Abstract:

A facile and robust strategy is required to fabricate films with high special optical properties for application in the field of anti-counterfeit marking. Nanocellulose, derived from bioresources, is a renewable material with broad application prospects. In this paper, a method for grafting the eco-friendly Berberine cationic dye on cellulose nanofiber is proposed. A functional modification was carried out by in-situ polymerization along with a grafting approach with acrylic acid(AA) in order to develop cationic dyeability of the cellulose nanofiber (CNF). The Berberine grafting on nanocellulose was significantly influenced by the reaction time and temperature during the dyeing process. The dyed CNF-films exhibited appropriate characteristics like appearance, color strength, and fastness for anti-counterfeiting application.

Keywords: Cellulose nanofiber, Berberine, Grafting, anti-counterfeiting, film

Procedia PDF Downloads 132

Authors: E. Zafeiraki, P. Nisianakis, K. Machera

Abstract:

Cannabis plant contains 113 cannabinoids and it is commonly known for its psychoactive substance tetrahydrocannabinol or as a source of narcotic substances. The recent years’ cannabis cultivation also increases due to its wide use both for medical and industrial purposes as well as for uses as para-pharmaceuticals, cosmetics and food commodities. Depending on the final product, different parts of the plant are utilized, with the leaves and bud (seeds) being the most frequently used. Cannabis can accumulate various contaminants, including heavy metals, both from the soil and the water in which the plant grows. More specifically, metals may occur naturally in the soil and water, or they can enter into the environment through fertilizers, pesticides and fungicides that are commonly applied to crops. The high probability of metals accumulation in cannabis, combined with the latter growing use, raise concerns about the potential health effects in humans and consequently lead to the need for the implementation of safety measures for cannabis products, such as guidelines for regulating contaminants, including metals, and especially the ones characterized by high toxicity in cannabis. Acknowledging the above, the aim of the current study was first to investigate metals contamination in cannabis samples collected from Greece, and secondly to examine potential differences in metals accumulation among the different parts of the plant. To our best knowledge, this is the first study presenting information on elements in cannabis cultivated in Greece, and also on the distribution pattern of the former in the plant body. To this end, the leaves and the seeds of all the samples were initially separated and dried and then digested with Nitric acid (HNO₃) and Hydrochloric acid (HCl). For the analysis of these samples, an Inductive Coupled Plasma-Mass Spectrometry (ICP-MS) method was developed, able to quantify 28 elements. Internal standards were added at a constant rate and concentration to all calibration standards and unknown samples, while two certified reference materials were analyzed in every batch to ensure the accuracy of the measurements. The repeatability of the method and the background contamination were controlled by the analysis of quality control (QC) standards and blank samples in every sequence, respectively. According to the results, essential metals, such as Ca, Zn and Mg, were detected at high levels. On the contrary, the concentration of high toxicity metals, like As (average: 0.10ppm), Pb (average: 0.36ppm), Cd (average: 0.04ppm), and Hg (average: 0.012ppm) were very low in all the samples, indicating that no harmful effects on human health can be caused by the analyzed samples. Moreover, it appears that the pattern of contamination of metals is very similar in all the analyzed samples, which could be attributed to the same origin of the analyzed cannabis, i.e., the common soil composition, use of fertilizers, pesticides, etc. Finally, as far as the distribution pattern between the different parts of the plant is concerned, it was revealed that leaves present a higher concentration in comparison to seeds for all metals examined.

Keywords: cannabis, heavy metals, ICP-MS, leaves and seeds, elements

Procedia PDF Downloads 99

Authors: Hosein Maghsoudi

Abstract:

Rheumatois arthritis (RA) is progressive inflammatory autoimmune diseases that primarily affect the joints, characterized by synovial hyperplasia and inflammatory cell infiltration, deformed and painful joints, which can lead tissue destruction, functional disability systemic complications, and early dead and socioeconomic costs. The cause of rheumatoid arthritis is unknown, but genetic and environmental factors are contributory and the prognosis is guarded. However, advances in understanding the pathogenesis of the disease have fostered the development of new therapeutics, with improved outcomes. The current treatment strategy, which reflects this progress, is to initiate aggressive therapy soon after diagnosis and to escalate the therapy, guided by an assessment of disease activity, in pursuit of clinical remission. The pathobiology of RA is multifaceted and involves T cells, B cells, fibroblast-like synoviocyte (FLSc) and the complex interaction of many pro-inflammatory cytokine. Novel biologic agents that target tumor necrosis or interlukin (IL)-1 and Il-6, in addition T- and B-cells inhibitors, have resulted in favorable clinical outcomes in patients with RA. Despite this, at least 30% of RA patients are résistance to available therapies, suggesting novel mediators should be identified that can target other disease-specific pathway or cell lineage. Among the inflammatory cell population that might participated in RA pathogenesis, FLSc are crucial in initiaing and driving RA in concert of cartilage and bone by secreting metalloproteinase (MMPs) into the synovial fluid and by direct invasion into extracellular matrix (ECM), further exacerbating joint damage. Invasion of fibroblast-like synoviocytes (FLSc) is critical in the pathogenesis of rheumatoid-arthritis. The metalloproteinase (MMPs) and activator of Toll-like receptor 4 (TLR4)/nuclear factor- κB pthway play a critical role in RA-FLS invasion induced by lipopolysaccharide (LPS). The present study aimed to explore the anti-invasion activity of Glycyrrhizic Acid as a pharmacologically safe phytochemical agent with potent anti-inflammatory properties on IL-1beta and TNF-alpha signalling pathways in Bovine fibroblast-like synoviocyte ex- vitro, on LPS-stimulated bovine FLS migration and invasion as well as MMP expression and explored the upstream signal transduction. Results showed that Glycyrrhizic Acid suppressed LPS-stimulated bovine FLS migration and invasion by inhibition MMP-9 expression and activity. In addition our results revealed that Glycyrrhizic Acid inhibited the transcriptional activity of MMP-9 by suppression the nbinding activity of NF- κB in the MMP-9 promoter pathway. The extract of licorice (Glycyrrhiza glabra L.) has been widely used for many centuries in the traditional Chinese medicine as native anti-allergic agent. Glycyrrhizin (GL), a triterpenoidsaponin, extracted from the roots of licorice is the most effective compound for inflammation and allergic diseases in human body. The biological and pharmacological studies revealed that GL possesses many pharmacological effects, such as anti-inflammatory, anti-viral and liver protective effects, and the biological effects, such as induction of cytokines (interferon-γ and IL-12), chemokines as well as extrathymic T and anti-type 2 T cells. GL is known in the traditional Chinese medicine for its anti-inflammatory effect, which is originally described by Finney in 1959. The mechanism of the GL-induced anti-inflammatory effect is based on different pathways of the GL-induced selective inhibition of the prostaglandin E2 production, the CK-II- mediated activation of both GL-binding lipoxygenas (gbLOX; 17) and PLA2, an anti-thrombin action of GL and production of the reactive oxygen species (ROS; GL exerts liver protection properties by inhibiting PLA2 or by the hydroxyl radical trapping action, leading to the lowering of serum alanine and aspartate transaminase levels. The present study was undertaken to examine the possible mechanism of anti-inflammatory properties GL on IL-1beta and TNF-alpha signalling pathways in bovine fibroblast-like synoviocyte ex-vivo, on LPS-stimulated bovine FLS migration and invasion as well as MMP expression and explored the upstream signal transduction. Our results clearly showed that treatment of bovine fibroblast-like synoviocyte with GL suppressed LPS-induced cell migration and invasion. Furthermore, it revealed that GL inhibited the transcription activity of MMP-9 by suppressing the binding activity of NF-κB in the MM-9 promoter. MMP-9 is an important ECM-degrading enzyme and overexpression of MMPs in important of RA-FLSs. LPS can stimulate bovine FLS to secret MMPs, and this induction is regulated at the transcription and translational levels. In this study, LPS treatment of bovine FLS caused an increase in MMP-2 and MMP-9 levels. The increase in MMP-9 expression and secretion was inhibited by ex- vitro. Furthermore, these effects were mimicked by MMP-9 siRNA. These result therefore indicate the the inhibition of LPS-induced bovine FLS invasion by GL occurs primarily by inhibiting MMP-9 expression and activity. Next we analyzed the functional significance of NF-κB transcription of MMP-9 activation in Bovine FLSs. Results from EMSA showed that GL suppressed LPS-induced NF-κB binding to the MMP-9 promotor, as NF-κB regulates transcriptional activation of multiple inflammatory cytokines, we predicted that GL might target NF-κB to suppress MMP-9 transcription by LPS. Myeloid differentiation-factor 88 (MyD88) and TIR-domain containing adaptor protein (TIRAP) are critical proteins in the LPS-induced NF-κB and apoptotic signaling pathways, GL inhibited the expression of TLR4 and MYD88. These results demonstrated that GL suppress LPS-induced MMP-9 expression through the inhibition of the induced TLR4/NFκB signaling pathway. Taken together, our results provide evidence that GL exerts anti-inflammatory effects by inhibition LPS-induced bovine FLSs migration and invasion, and the mechanisms may involve the suppression of TLR4/NFκB –mediated MMP-9 expression. Although further work is needed to clarify the complicated mechanism of GL-induced anti-invasion of bovine FLSs, GL might be used as a further anti-invasion drug with therapeutic efficacy in the treatment of immune-mediated inflammatory disease such as RA.

Keywords: glycyrrhizic acid, bovine fibroblast-like synoviocyte, tlr4/nf-κb, metalloproteinase-9

Procedia PDF Downloads 391

Authors: Ambrish Singh

Abstract:

The corrosion inhibition performance of pyran derivatives (AP) on mild steel in 15% HCl was investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, weight loss, contact angle, and scanning electron microscopy (SEM) measurements, DFT and molecular dynamic simulation. The adsorption of APs on the surface of mild steel obeyed Langmuir isotherm. The potentiodynamic polarization study confirmed that inhibitors are mixed type with cathodic predominance. Molecular dynamic simulation was applied to search for the most stable configuration and adsorption energies for the interaction of the inhibitors with Fe (110) surface. The theoretical data obtained are, in most cases, in agreement with experimental results.

Keywords: acidizing inhibitor, pyran derivatives, DFT, molecular simulation, mild steel, EIS

Procedia PDF Downloads 196

Authors: S. Junaid S. Qazi, Denice C. Bay, Raymond Chew, Raymond J. Turner

Abstract:

EmrE, a member of the small multidrug resistance protein family in bacteria is considered to be the archetypical member of its family. It confers host resistance to a wide variety of quaternary cation compounds (QCCs) driven by proton motive force. Generally, purification yield is a challenge in all membrane proteins because of the difficulties in their expression, isolation and solubilization. EmrE is extremely hydrophobic which make the purification yield challenging. We have purified EmrE protein using two different approaches: organic solvent membrane extraction and hexahistidine (his6) tagged Ni-affinity chromatographic methods. We have characterized changes present between ligand affinity of untagged and his6-tagged EmrE proteins in similar membrane mimetic environments using biophysical experimental techniques. Purified proteins were solubilized in a buffer containing n-dodecyl-β-D-maltopyranoside (DDM) and the conformations in the proteins were explored in the presence of four QCCs, methyl viologen (MV), ethidium bromide (EB), cetylpyridinium chloride (CTP) and tetraphenyl phosphonium (TPP). SDS-Tricine PAGE and dynamic light scattering (DLS) analysis revealed that the addition of QCCs did not induce higher multimeric forms of either proteins at all QCC:EmrE molar ratios examined under the solubilization conditions applied. QCC binding curves obtained from the Trp fluorescence quenching spectra, gave the values of dissociation constant (Kd) and maximum specific one-site binding (Bmax). Lower Bmax values to QCCs for his6-tagged EmrE shows that the binding sites remained unoccupied. This lower saturation suggests that the his6-tagged versions provide a conformation that prevents saturated binding. Our data demonstrate that tagging an integral membrane protein can significantly influence the protein.

Keywords: small multidrug resistance (SMR) protein, EmrE, integral membrane protein folding, quaternary ammonium compounds (QAC), quaternary cation compounds (QCC), nickel affinity chromatography, hexahistidine (His6) tag

Procedia PDF Downloads 379

Authors: Reyhan Özdoğan, Mithat Çelebi, Özgür Ceylan, Mehmet Arif Kaya

Abstract:

Super absorbent polymers (SAPs) are defined as materials that can absorb huge amount of water or aqueous solution in comparison to their own mass and retain in their lightly cross-linked structure. SAPs were produced from water soluble monomers via polymerization subsequently controlled crosslinking. SAPs are generally used for water absorbing applications such as baby diapers, patient or elder pads and other hygienic product industries. Crosslinking density (CD) of SAP structure is an essential factor for water absortion capacity (WAC). Low internal CD leads to high WAC values and vice versa. However, SAPs have low CD and high swelling capacities and tend to disintegrate when pressure is applied upon them, so SAPs under load cannot absorb liquids effectively. In order to prevent this undesired situation and to obtain suitable SAP structures having high swelling capacity and ability to work under load, surface crosslinking can be the answer. In industry, these superabsorbent gels are mostly produced via solution polymerization and then they need to be dried, grinded, sized, post polymerized and finally surface croslinked (involves spraying of a crosslinking solution onto dried and grinded SAP particles, and then curing by heat). It can easily be seen that these steps are time consuming and should be handled carefully for the desired final product. If we could synthesize desired final SAPs using less processes it will help reducing time and production costs which are very important for any industries. In this study, synthesis of SAPs were achieved successfully by inverse suspension (Pickering type) polymerization and subsequently in-situ surface cross-linking via using proper surfactants in high boiling point solvents. Our one-pot synthesis of surface cross-linked SAPs invovles only one-step for preparation, thus it can be said that this technique exhibits more preferable characteristic for the industry in comparison to conventional methods due to its one-step easy process. Effects of different surface crosslinking agents onto properties of poly(acrylic acid-co-sodium acrylate) based SAPs are investigated. Surface crosslink degrees are evaluated by swelling under load (SUL) test. It was determined water absorption capacities of obtained SAPs decrease with the increasing surface crosslink density while their mechanic properties are improved.

Keywords: inverse suspension polymerization, polyacrylic acid, super absorbent polymers (SAPs), surface crosslinking, sodium polyacrylate

Procedia PDF Downloads 323

Authors: B. González-Yebra, B. Flores-Nieto, P. Aguilar-Salinas, M. Preciado Puga, A. L. González Yebra

Abstract:

The monitoring of populations occupationally exposed to organic solvents has been an important issue for several shoe factories for years since the International Agency for Research on Cancer (IARC) has advised on the potential carcinogenic risk of chemicals related to occupations. In order to detect if exposition to organic solvents used in some Mexican shoe factories contributes to oral carcinogenesis, we performed monitoring in three factories. Occupational exposure was determined by using monitors 3M. Organic solvents were assessed by gas chromatography. Then, we recruited 30 shoe workers (30.2 ± 8.4 years) and 10 unexposed subjects (43.3 ± 11.2 years) for the micronuclei (MN) test and immunodetection of some cancer biomarkers (ki-67, p16, caspase-3) in scraped oral epithelial cells. Monitored solvents detected were acetone, benzene, hexane, methyl ethyl ketone, and toluene in acceptable levels according to Official Mexican Norm. We found by MN test higher incidence of nuclear abnormalities (karyorrhexis, pycnosis, karyolysis, condensed chromatin, and macronuclei) in the exposed group than the non-exposed group. On the other hand, we found, a negative expression for Ki-67 and p16 in exfoliated epithelial cells from exposed and non-exposed to organic solvents subjects. Only caspase-3 shown positive patter of expression in 9/30 (30%) exposed subjects, and we detected high karyolysis incidence in caspase-3 subjects (p = 0.021). The absence of expression of proliferation markers p16 and ki-67 and presence of apoptosis marker caspase-3 are indicating the absence of malignancy in oral epithelial cells and low risk for oral cancer. It is a fact that the MN test is a very effective method to detect nuclear abnormalities in exfoliated buccal cells from subjects that have been exposed to organic solvents in the shoe industry. However, in order to improve this tool and predict cancer risk is it is mandatory to implement complementary tests as other biomarkers that can help to detect malignancy in individuals occupationally exposed.

Keywords: biomarkers, oral cancer, organic solvents, shoe industries

Procedia PDF Downloads 136

Authors: Fiúza A., Góis J. Leite M., Braga H., Lima A., Jorge P., Moutela P., Martins L., Futuro A.

Abstract:

Lepidolite is an important lithium mineral that, to the author’s best knowledge, has not been used to produce lithium hydroxide, necessary for energy conversion to electric vehicles. Alkaline leaching of lithium concentrates allows the establishment of a production diagram avoiding most of the environmental drawbacks that are associated with the usage of acid reagents. The tested processes involve a pretreatment by digestion at high temperatures with additives, followed by leaching at hot atmospheric pressure. The solutions obtained must be compatible with solutions from the leaching of spodumene concentrates, allowing the development of a common treatment diagram, an important accomplishment for the feasible exploitation of Portuguese resources. Statistical programming and interpretation techniques are used to minimize the laboratory effort required by conventional approaches and also allow phenomenological comprehension.

Keywords: artificial intelligence, tailings free process, ferroelectric electrolyte battery, life cycle assessment

Procedia PDF Downloads 122

Authors: Majid Farsadrouh Rashti, Alireza Mohammadinejad, Amir Shafiee Kisomi

Abstract:

Lead (Pb²⁺), a cation, is a prime constituent of the majority of the industrial effluents such as mining, smelting and coal combustion, Pb-based painting and Pb containing pipes in water supply systems, paper and pulp refineries, printing, paints and pigments, explosive manufacturing, storage batteries, alloy and steel industries. The maximum permissible limit of lead in the water used for drinking and domesticating purpose is 0.01 mg/L as advised by Bureau of Indian Standards, BIS. This becomes the acceptable 'safe' level of lead(II) ions in water beyond which, the water becomes unfit for human use and consumption, and is potential enough to lead health problems and epidemics leading to kidney failure, neuronal disorders, and reproductive infertility. Superabsorbent hydrogels are loosely crosslinked hydrophilic polymers that in contact with aqueous solution can easily water and swell to several times to their initial volume without dissolving in aqueous medium. Superabsorbents are kind of hydrogels capable to swell and absorb a large amount of water in their three-dimensional networks. While the shapes of hydrogels do not change extensively during swelling, because of tremendously swelling capacity of superabsorbent, their shape will broadly change.Because of their superb response to changing environmental conditions including temperature pH, and solvent composition, superabsorbents have been attracting in numerous industrial applications. For instance, water retention property and subsequently. Natural-based superabsorbent hydrogels have attracted much attention in medical pharmaceutical, baby diapers, agriculture, and horticulture because of their non-toxicity, biocompatibility, and biodegradability. Novel superabsorbent hydrogel nanocomposites were prepared by graft copolymerization of acrylamide and itaconic acid in the presence of nanoclay (laponite), using methylene bisacrylamide (MBA) and potassium persulfate, former as a crosslinking agent and the second as an initiator. The superabsorbent hydrogel nanocomposites structure was characterized by FTIR spectroscopy, SEM and TGA Spectroscopy adsorption of metal ions on poly (AAm-co-IA). The equilibrium swelling values of copolymer was determined by gravimetric method. During the adsorption of metal ions on polymer, residual metal ion concentration in the solution and the solution pH were measured. The effects of the clay content of the hydrogel on its metal ions uptake behavior were studied. The NC hydrogels may be considered as a good candidate for environmental applications to retain more water and to remove heavy metals.

Keywords: adsorption, hydrogel, nanocomposite, super adsorbent

Procedia PDF Downloads 187

Authors: Abdelaziz Ghrib, Samir Hattali, Mouloud Ghrib, Mohamed Lamine Aouissia, David Ruch

Abstract:

In the present study, the solid solutions with a chemical composition of Zr0.8Y0.2-xLaxO2 (x=0, 0.1, 0.2) were synthesized via two routes, by hydrothermal method using NaOH as precipitating agent at 230°C for 15h and by the sol–gel process using citric acid as complexing agent. Compounds have been characterized by powder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Thermo gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) techniques for appropriate characterization of the distinct thermal events occurring during synthesis. All the compounds crystallize in cubic fluorite structure, as indicated by X-ray diffraction studie. The microstructure of oxides synthesized by sol-gel showed porosity that increased with the lanthanum La3+ contents compared to hydrothermal method which gives a single crystal oxide.

Keywords: oxide, hydrothermal, rare earth, solubility, sol-gel, ternary mixture

Procedia PDF Downloads 642

Authors: R. S. Giraddi, C. M. Poleshi

Abstract:

Organic cultivation of crops is gaining importance consumer awareness towards pesticide residue free foodstuffs is increasing globally. This is also because of high costs of synthetic fertilizers and pesticides, making the conventional farming non-remunerative. In India, organic manures (such as vermicompost) are an important input in organic agriculture.  Though vermicompost obtained through earthworm and microbe-mediated processes is known to comprise most of the crop nutrients, but they are in small amounts thus necessitating enrichment of nutrients so that crop nourishment is complete. Another characteristic of organic manures is that the pest infestations are kept under check due to induced resistance put up by the crop plants. In the present investigation, deoiled neem cake containing azadirachtin, copper ore tailings (COT), a source of micro-nutrients and microbial consortia were added for enrichment of vermicompost. Neem cake is a by-product obtained during the process of oil extraction from neem plant seeds. Three enriched vermicompost blends were prepared using vermicompost (at 70, 65 and 60%), deoiled neem cake (25, 30 and 35%), microbial consortia and COTwastes (5%). Enriched vermicompost was thoroughly mixed, moistened (25+5%), packed and incubated for 15 days at room temperature. In the crop response studies, the field trials on chili (Capsicum annum var. longum) and soybean, (Glycine max cv JS 335) were conducted during Kharif 2015 at the Main Agricultural Research Station, UAS, Dharwad-Karnataka, India. The vermicompost blend enriched with neem cake (known to possess higher amounts of nutrients) and vermicompost were applied to the crops and at two dosages and at two intervals of crop cycle (at sowing and 30 days after sowing) as per the treatment plan along with 50% recommended dose of fertilizer (RDF). 10 plants selected randomly in each plot were studied for pest density and plant damage. At maturity, crops were harvested, and the yields were recorded as per the treatments, and the data were analyzed using appropriate statistical tools and procedures. In the crops, chili and soybean, crop nourishment with neem enriched vermicompost reduced insect density and plant damage significantly compared to other treatments. These treatments registered as much yield (16.7 to 19.9 q/ha) as that realized in conventional chemical control (18.2 q/ha) in soybean, while 72 to 77 q/ha of green chili was harvested in the same treatments, being comparable to the chemical control (74 q/ha). The yield superiority of the treatments was of the order neem enriched vermicompost>conventional chemical control>neem cake>vermicompost>untreated control.  The significant features of the result are that it reduces use of inorganic manures by 50% and synthetic chemical insecticides by 100%.

Keywords: humic acid, azadirachtin, vermicompost, insect-pest

Procedia PDF Downloads 277

Authors: Madelyn N. Moawad, Hermine R. Z. Tadros, Mary G. Ghobrial, Ahmad R. Bassiouny, Kamal M. Kandeel, Athar Ata

Abstract:

Seaweeds are potential renewable resources in marine environment. They provide an excellent source of bioactive substances such as dietary fibers and various functional polysaccharides that could potentially be used as ingredients for both human and animal health applications. The observations suggested that these bioactive compounds have strong antioxidant properties, which have beneficial effects on human health. The present research aimed at finding new chemical products from local marine macroalgae for natural medicinal uses and consumption for their nutritional values. Macroalgae samples were collected manually mainly from the Mediterranean Sea at shallow subtidal zone of Abu Qir Bay, Alexandria, Egypt. The chemical compositions of lyophilized materials of six selected macroalgal species; Colpomenia sinuosa, Sargassum linifolium, Padina pavonia, Pterocladiella capillacea, Laurencia pinnatifidia, and Caulerpa racemosa, were investigated for proteins using bovine serum albumin, and carbohydrates were assayed by phenol-sulfuric acid reaction. The macroalgae lipid was extracted with chloroform, methanol and phosphate buffer. Vitamins were extracted using trichloroacetic acid. Chlorophylls and total carotenoids were determined spectrophotometrically and total phenols were extracted with methanol. In addition, lipid-soluble, and water-soluble antioxidant, and anti α-glucosidase activities were measured spectrophotometrically. The antioxidant activity of hexane extracts was investigated using phosphomolybdenum reagent. The anti-α-glucosidase effect measurement was initiated by mixing α-glucosidase solution with p-nitrophenyl α-D-glucopyranoside. The results showed that the ash contents varied from 11.2 to 35.4 % on dry weight basis for P. capillacea and Laurencia pinnatifidia, respectively. The protein contents ranged from 5.63 % in brown macroalgae C. sinuosa to 8.73 % in P. pavonia. A relative wide range in carbohydrate contents was observed (20.06–46.75 %) for the test algal species. The highest lipid percentage was found in green alga C. racemosa (5.91%) followed by brown algae P. pavonia (3.57%) and C. sinuosa (2.64%). The phenolic contents varied from 1.32 mg GAE/g for C. sinuosa to 4.00 mg GAE/g in P. pavonia. The lipid-soluble compounds exhibited higher antioxidant capacity (73.18-145.95 µM/g) than that of the water-soluble ones ranging from 24.83 µM/g in C. racemosa to 74.07 µM/g in S. linifolium. The most potent anti-α-glucosidase activity was observed for P. pavonia with IC50 of 17.12 μg/ml followed by S. linifolium (IC50 = 71.75 μg/ml), C. racemosa (IC50 = 84.73 μg/ml), P. capillacea (IC50 = 92.16 μg/ml), C. sinuosa (IC50 = 112.44 μg/ml), and L. pinnatifida (IC50 = 115.11 μg/ml).

Keywords: α-glucosidase, lyophilized, macroalgae, spectrophotometrically

Procedia PDF Downloads 303

Authors: Fairouz Tazerouti, Samira Ihadadene

Abstract:

Pyrethroids are synthetic pesticides that originated from the modification of natural pyrethrins to improve their biological activity and stability. They are a family of chiral pesticides with a large number of stereoisomers. Enantiomers of synthetic pyretroids present different insecticidal activity, toxicity against aquatic invertebrates and persistence in the environment so the development of rapid and sensitive chiral methods for the determination of different enantiomers is necessary. In this study, the separation of enantiomers of pyrethroid insecticides has been systematically studied using three commercially chiral high-performance liquid chromatography columns. Useful resolution was obtained for compounds with a variety of acid and alcohol moieties, and containing one to four chiral centres. The chromatographic behaviour of the diastereomers of some of these insecticides by using normal, polar and reversed mobile phase mode were also examined.

Keywords: pesticides, analysis, liquid chromatography, pyrethroids

Procedia PDF Downloads 377

Authors: F. Ait Ahsene-Aissat, Y. Kerchiche, Y. Moussaoui, M. Hachemi

Abstract:

Environmental pollution is at the heart of the debate today, the pollutants released into the atmosphere must be measured and reduced to the norms of international releases. The industries pollution is caused by emissions of SO₂, CO and heavy metals in volatile form that must be quantified and monitored. This study presents a qualitative and quantitative analysis However, the collection of volatile heavy metals were performed by active sampling using an isokinetic. SO₂ gas for the maximum is reached for a value of 343 mg / m³, the SO₂ concentration far exceeds the standard releases SO₂ followed by incineration industries in Algeria. the concentration of Cr exceeds 8 times the standard, the Pb concentration in the excess of 6 times, the concentration of Fe has reached very high values exceeding the standard 30 times, the Zn concentration in the excess of 5 times, and the Ni the excess of 4 times and finally that of Cu is almost double of the standard.

Keywords: SO₂, CO, volatiles metals, active sampling isokinetic

Procedia PDF Downloads 297

Authors: L. C. Nwosu, C. O. Adedire, M. O. Ashamo, E. O. Ogunwolu

Abstract:

The maize weevil, Sitophilus zeamais Motschulsky is a notorious pest of stored maize (Zea mays L.). The development of resistant maize varieties to manage weevils is a major breeding objective. The study investigated the parameters and mechanisms that confer resistance on a maize variety to S. zeamais infestation using twenty elite maize varieties. Detailed morphological, physical and chemical studies were conducted on whole-maize grain and the grain pericarp. Resistance was assessed at 33, 56, and 90 days post infestation using weevil mortality rate, weevil survival rate, percent grain damage, percent grain weight loss, weight of grain powder, oviposition rate and index of susceptibility as indices rated on a scale developed by the present study and on Dobie’s modified scale. Linear regression models that can predict maize grain damage in relation to the duration of storage were developed and applied. The resistant varieties identified particularly 2000 SYNEE-WSTR and TZBRELD3C5 with very high degree of resistance should be used singly or best in an integrated pest management system for the control of S. zeamais infestation in stored maize. Though increases in the physical properties of grain hardness, weight, length, and width increased varietal resistance, it was found that the bases of resistance were increased chemical attributes of phenolic acid, trypsin inhibitor and crude fibre while the bases of susceptibility were increased protein, starch, magnesium, calcium, sodium, phosphorus, manganese, iron, cobalt and zinc, the role of potassium requiring further investigation. Characters that conferred resistance on the test varieties were found distributed in the pericarp and the endosperm of the grains. Increases in grain phenolic acid, crude fibre, and trypsin inhibitor adversely and significantly affected the bionomics of the weevil on further assessment. The flat side of a maize grain at the point of penetration was significantly preferred by the weevil. Why the south area of the flattened side of a maize grain was significantly preferred by the weevil is clearly unknown, even though grain-face-type seemed to be a contributor in the study. The preference shown to the south area of the grain flat side has implications for seed viability. The study identified antibiosis, preference, antixenosis, and host evasion as the mechanisms of maize post harvest resistance to Sitophilus zeamais infestation.

Keywords: maize weevil, resistant, parameters, mechanisms, preference

Procedia PDF Downloads 307

Authors: Valentine A. Chanturiya, Igor Zh. Bunin, Maria V. Ryazantseva

Abstract:

The modification of structural and chemical properties of fluorite, scheelite and calcite under the impact of high-power electromagnetic pulses (HPEMP-treatment) were studied with the help of adsorption of acid-base indicators and atomic – force microscopy (AFM). The HPEMP-treatment during the space of 30 seconds resulted in the intensification of fluorite surface the electron-donating ability and acceptor properties of calcite and scheelite surfaces. High-power electromagnetic treatment of the single minerals resulted in the improvement of the calciferous minerals floatability. The rising of the scheelite recovery is 10 – 12%, fluorite – 5 – 6%, calcite – 7 – 8%.

Keywords: calcite, fluorite, scheelite, high power electromagnetic pulses, floatability

Procedia PDF Downloads 288

Authors: Neera Singh, Devendra Kumar, Om Parkash

Abstract:

We have synthesized nanocrystalline Fe-Ni alloy powders where Ni varies as 10, 30 and 50 mole% by a wet chemical route (sol-gel auto-combustion) followed by reduction in hydrogen atmosphere. The ratio of citrate to nitrate was maintained at 0.3 where citric acid has worked as a fuel during combustion. The reduction of combusted powders was done at 700°C/1h in hydrogen atmosphere using an atmosphere controlled quartz tube furnace. Phase and microstructure analysis has shown the formation of α-(Fe,Ni) and γ-(Fe,Ni) phases after reduction. An increase in Ni concentration resulted in more γ-(Fe,Ni) formation where complete γ-(Fe,Ni) formation was achieved at 50 mole% Ni concentration. Formation of particles below 50 nm size range was confirmed using Scherrer’s formula and Transmission Electron Microscope. The work is aimed at the effect of Ni concentration on phase, microstructure and magnetic properties of synthesized alloy powders.

Keywords: combustion, microstructure, nanocrystalline, reduction

Procedia PDF Downloads 181

Authors: Varun Mittal, Shishir Sinha

Abstract:

The present experimental study focused on the hardness behavior of bagasse fiber-epoxy composites. The relationship between bagasse fiber content and effect of chemical treatment on bagasse fiber as a function of Brinell hardness of bagasse fiber epoxy was investigated. Bagasse fiber was treated with sodium hydroxide followed by acrylic acid before they were reinforced with epoxy resin. Compared hardness properties with the untreated bagasse filled epoxy composites. It was observed that Brinell hardness increased up to 15 wt% fiber content and further decreases, however, chemical treatment also improved the hardness properties of composites.

Keywords: bagasse fiber, composite, hardness, sodium hydroxide

Procedia PDF Downloads 286

Authors: Suheyla Kocaman, Gulnare Ahmetli

Abstract:

In this study, acrylated soybean oil (AESO) was used as modifying agent for DGEBF-type epoxy resin (ER). AESO was used as a co-matrix in 50 wt % with ER. Composites with eco-friendly natural fillers-banana bark and seashell were prepared. MNA was used as a hardener. Effect of banana peel (BP) and seashell (SSh) fillers on mechanical properties, such as tensile strength, elongation at break, and hardness of M-ERs were investigated. The structure epoxy resins (M-ERs) cured with MNA and sebacic acid (SAc) hardeners were characterized by Fourier transform infrared spectroscopy (FTIR). Tensile test results show that Young’s (elastic) modulus, tensile strength and hardness of SSh particles reinforced with M-ERs were higher than the M-ERs reinforced with banana bark.

Keywords: biobased composite, epoxy resin, mechanical properties, natural fillers

Procedia PDF Downloads 240

Authors: E. Nemes-Nagy, E. Fogarasi, M. Croitoru, A. Nyárádi, K. Komlódi, S. Pál, A. Kovács, O. Kopácsy, R. Tripon, Z. Fazakas, C. Uzun, Z. Simon-Szabó, V. Balogh-Sămărghițan, E. Ernő Nagy, M. Szabó, M. Tilinca

Abstract:

Intense oxidative stress, increased glycated hemoglobin and mineral imbalance represent risk factors for complications in diabetic patients. Cardiovascular complications are most common in these patients, including nephropathy. This study was conducted in 2015 at the Procardia Laboratory in Tîrgu Mureș, Romania on 40 type 2 diabetic adults. Routine biochemical tests were performed on the Konleab 20XTi analyzer (serum glucose, total cholesterol, LDL and HDL cholesterol, triglyceride, creatinine, urea). We also measured serum uric acid, magnesium and calcium concentration by photometric procedures, potassium, sodium and chloride by ion selective electrode, and chromium by atomic absorption spectrometry in a group of patients. Glycated hemoglobin (HbA1c) dosage was made by reflectometry. Urine analysis was performed using the HandUReader equipment. The level of oxidative stress was measured by serum malondialdehyde dosage using the thiobarbituric acid reactive substances method. MDRD (Modification of Diet in Renal Disease) formula was applied for calculation of creatinine-derived glomerular filtration rate. GraphPad InStat software was used for statistical analysis of the data. The diabetic subject included in the study presented high MDA concentrations, showing intense oxidative stress. Calcium was deficient in 5% of the patients, chromium deficiency was present in 28%. The atherogenic cholesterol fraction was elevated in 13% of the patients. Positive correlation was found between creatinine and MDRD-creatinine values (p<0.0001), 68% of the patients presented increased creatinine values. The majority of the diabetic patients had good control of their diabetes, having optimal HbA1c values, 35% of them presented fasting serum glucose over 120 mg/dl and 18% had glucosuria. Intense oxidative stress and mineral deficiencies can increase the risk of cardiovascular complications in diabetic patients in spite of their good metabolic balance. More than two third of the patients present biochemical signs of nephropathy, cystatin C dosage and microalbuminuria could reveal better the kidney disorder, but glomerular filtration rate calculation formulas are also useful for evaluation of renal function.

Keywords: cardiovascular risk, homocysteine, malondialdehyde, metformin, minerals, type 2 diabetes, vitamin B12

Procedia PDF Downloads 319