Search results for: liquid organic fertilizer
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4395

Search results for: liquid organic fertilizer

3105 BOFSC: A Blockchain Based Decentralized Framework to Ensure the Transparency of Organic Food Supply Chain

Authors: Mifta Ul Jannat, Raju Ahmed, Al Mamun, Jannatul Ferdaus, Ritu Costa, Milon Biswas

Abstract:

Blockchain is an internet-based invention that is coveted in the permanent, scumbled record for its capacity to openly accept, record, and distribute transactions. In a traditional supply chain, there are no trustworthy participants for an organic product. Yet blockchain engineering may provide confidence, transparency, and traceability. Blockchain varies in how companies get real, checked, and lasting information from their supply chain and lock in customers. In an arrangement of cryptographic squares, Blockchain digitizes each connection by sparing it. No one person may alter the documents, and any alteration within the agreement is clear to all. The coming to the record is tamper proof and unchanging, offering a complete history of the object’s life cycle and minimizing opening for extorting. The primary aim of this analysis is to identify the underlying problem that the customer faces. In this post, we will minimize the allocation of fraud data through the ’Smart Contract’ and include a certificate of quality assurance.

Keywords: blockchain technology, food supply chain, Ethereum, smart contract, quality assurance, trustability, security, transparency

Procedia PDF Downloads 153
3104 Association between Levels of Volatile Organic Compound Metabolites and Cigarette Smoking-Related Urothelial Carcinoma

Authors: Chi-Jung Chung, Chao-Hsiang Chang, Chiu-Shong Liu, Sheng-Wei Li, Mu-Chi Chung, Ting-Jie Wen, Hui-Ling Lee

Abstract:

Cigarette smoke contains volatile organic compounds (VOCs), such as acrylamide, 1,3-butadiene, and benzene. This study aimed to explore the associations between the urinary levels of cotinine and VOC metabolites and the risk of urothelial carcinoma (UC). A hospital-based case–control study involving two groups matched on the basis of age ( ± 3 years) and gender was designed. UC was clinically diagnosed through urological examinations and pathologically verified. Smoking-related information was collected through questionnaires and face-to-face interviews with all study participants. Urine samples were collected for the analysis of the urinary levels of VOC metabolites, cotinine, and 8-hydroxydeoxygua- nosine (8-OHdG), which was selected as a proxy of oxidative stress. Multiple logistic regressions were applied to estimate the risk of UC. The urinary cotinine and 8-OHdG levels of the UC group were higher than those of the control group. The urinary levels of VOC metabolites, including N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA), N- acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine, N-acetyl-S- (4- hydroxy-2-buten-1-yl)-Lcysteine-3, trans, trans-muconic acid (t,t- MA), and S-phenylmercapturic acid (SPMA) increased as the urinary levels of cotinine increased. Relevant dose-response relationships between the risk of UC risk and the urinary levels of AAMA , t,t-MA, SPMA, and 8-OHdG were found after adjusting for potential risk factors. The UC risk of participants with high urinary levels of cotinine, AAMA, t,t-MA, SPMA, and 8-OHdG were 3.5–6-fold higher than those of other participants. Increased urinary levels of VOC metabolites were associated with smoking-related UC risk. The development of UC should be explored in large-scale in vitro or in vivo studies with the repeated measurement of VOC metabolites.

Keywords: volatile organic compound, urothelial carcinoma, cotinine, 8-hydroxydeoxyguanosine

Procedia PDF Downloads 142
3103 A Validated UPLC-MS/MS Assay Using Negative Ionization Mode for High-Throughput Determination of Pomalidomide in Rat Plasma

Authors: Muzaffar Iqbal, Essam Ezzeldin, Khalid A. Al-Rashood

Abstract:

Pomalidomide is a second generation oral immunomodulatory agent, being used for the treatment of multiple myeloma in patients with disease refractory to lenalidomide and bortezomib. In this study, a sensitive UPLC-MS/MS assay was developed and validated for high-throughput determination of pomalidomide in rat plasma using celecoxib as an internal standard (IS). Liquid liquid extraction using dichloromethane as extracting agent was employed to extract pomalidomide and IS from 200 µL of plasma. Chromatographic separation was carried on Acquity BEHTM C18 column (50 × 2.1 mm, 1.7 µm) using an isocratic mobile phase of acetonitrile:10 mM ammonium acetate (80:20, v/v), at a flow rate of 0.250 mL/min. Both pomalidomide and IS were eluted at 0.66 ± 0.03 and 0.80 ± 0.03 min, respectively with a total run time of 1.5 min only. Detection was performed on a triple quadrupole tandem mass spectrometer using electrospray ionization in negative mode. The precursor to product ion transitions of m/z 272.01 → 160.89 for pomalidomide and m/z 380.08 → 316.01 for IS were used to quantify them respectively, using multiple reaction monitoring mode. The developed method was validated according to regulatory guideline for bioanalytical method validation. The linearity in plasma sample was achieved in the concentration range of 0.47–400 ng/mL (r2 ≥ 0.997). The intra and inter-day precision values were ≤ 11.1% (RSD, %) whereas accuracy values ranged from - 6.8 – 8.5% (RE, %). In addition, other validation results were within the acceptance criteria and the method was successfully applied in a pharmacokinetic study of pomalidomide in rats.

Keywords: pomalidomide, pharmacokinetics, LC-MS/MS, celecoxib

Procedia PDF Downloads 391
3102 Application of Artificial Ground-Freezing to Construct a Passenger Interchange Tunnel for the Subway Line 14 in Paris, France

Authors: G. Lancellotta, G. Di Salvo, A. Rigazio, A. Davout, V. Pastore, G. Tonoli, A. Martin, P. Jullien, R. Jagow-Klaff, R. Wernecke

Abstract:

Artificial ground freezing (AGF) technique is a well-proven soil improvement approach used worldwide to construct shafts, tunnels and many other civil structures in difficult subsoil or ambient conditions. As part of the extension of Line 14 of the Paris subway, a passenger interchange tunnel between the new station at Porte de CI ichy and the new Tribunal the Grand Instance has been successfully constructed using this technique. The paper presents the successful application of AGF by Liquid Nitrogen and Brine implemented to provide structural stability and groundwater cut-off around the passenger interchange tunnel. The working conditions were considered to be rather challenging, due to the proximity of a hundred-year-old existing service tunnel of the Line 13, and subsoil conditions on site. Laboratory tests were carried out to determine the relevant soil parameters for hydro-thermal-mechanical aspects and to implement numerical analyses. Monitoring data were used in order to check and control the development and the efficiency of the freezing process as well as to back analyze the parameters assumed for the design, both during the freezing and thawing phases.

Keywords: artificial ground freezing, brine method, case history, liquid nitrogen

Procedia PDF Downloads 225
3101 Lipid Nanoparticles for Spironolactone Delivery: Physicochemical Characteristics, Stability and Invitro Release

Authors: H. R. Kelidari, M. Saeedi, J. Akbari, K. Morteza-Semnani, H. Valizadeh

Abstract:

Spironolactoe (SP) a synthetic steroid diuretic is a poorly water-soluble drug with a low and variable oral bioavailability. Regarding to the good solubility of SP in lipid materials, SP loaded Solid lipid nanoparticles (SP-SLNs) and nanostructured lipid carrier (SP-SLNs) were thus prepared in this work for accelerating dissolution of this drug. The SP loaded NLC with stearic acid (SA) as solid lipid and different Oleic Acid (OA) as liquid lipid content and SLN without OA were prepared by probe ultrasonication method. With increasing the percentage of OA from 0 to 30 wt% in SLN/NLC, the average size and zeta potential of nanoparticles felled down and entrapment efficiency (EE %) rose dramatically. The obtained micrograph particles showed pronounced spherical shape. Differential Scanning Calorimeter (DSC) measurements indicated that the presence of OA reduced the melting temperature and melting enthalpy of solid lipid in NLC structure. The results reflected good long-term stability of the nanoparticles and the measurements show that the particle size remains lower in NLC compare to SLN formulations, 6 months after production. Dissolution of SP-SLN and SP-NLC was about 5.1 and 7.2 times faster than raw drugs in 120 min respectively. These results indicated that the SP loaded NLC containing 70:30 solid lipid to liquid lipid ratio is a suitable carrier of SP with improved drug EE and steady drug release properties.

Keywords: drug release, lipid nanoparticles, spironolactone, stability

Procedia PDF Downloads 331
3100 Total-Reflection X-Ray Spectroscopy as a Tool for Element Screening in Food Samples

Authors: Hagen Stosnach

Abstract:

The analytical demands on modern instruments for element analysis in food samples include the analysis of major, trace and ultra-trace essential elements as well as potentially toxic trace elements. In this study total reflection, X-ray fluorescence analysis (TXRF) is presented as an analytical technique, which meets the requirements, defined by the Association of Official Agricultural Chemists (AOAC) regarding the limit of quantification, repeatability, reproducibility and recovery for most of the target elements. The advantages of TXRF are the small sample mass required, the broad linear range from µg/kg up to wt.-% values, no consumption of gases or cooling water, and the flexible and easy sample preparation. Liquid samples like alcoholic or non-alcoholic beverages can be analyzed without any preparation. For solid food samples, the most common sample pre-treatment methods are mineralization, direct deposition of the sample onto the reflector without/with minimal treatment, mainly as solid suspensions or after extraction. The main disadvantages are due to the possible peaks overlapping, which may lower the accuracy of quantitative analysis and the limit in the element identification. This analytical technique will be presented by several application examples, covering a broad range of liquid and solid food types.

Keywords: essential elements, toxic metals, XRF, spectroscopy

Procedia PDF Downloads 133
3099 Natural and Construction/Demolition Waste Aggregates: A Comparative Study

Authors: Debora C. Mendes, Matthias Eckert, Claudia S. Moço, Helio Martins, Jean-Pierre Gonçalves, Miguel Oliveira, Jose P. Da Silva

Abstract:

Disposal of construction and demolition waste (C&DW) in embankments in the periphery of cities causes both environmental and social problems. To achieve the management of C&DW, a detailed analysis of the properties of these materials should be done. In this work we report a comparative study of the physical, chemical and environmental properties of natural and C&DW aggregates from 25 different origins. Assays were performed according to European Standards. Analysis of heavy metals and organic compounds, namely polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), were performed. Finally, properties of concrete prepared with C&DW aggregates are reported. Physical analyses of C&DW aggregates indicated lower quality properties than natural aggregates, particularly for concrete preparation and unbound layers of road pavements. Chemical properties showed that most samples (80%) meet the values required by European regulations for concrete and unbound layers of road pavements. Analyses of heavy metals Cd, Cr, Cu, Pb, Ni, Mo and Zn in the C&DW leachates showed levels below the limits established by the Council Decision of 19 December 2002. Identification and quantification of PCBs and PAHs indicated that few samples shows the presence of these compounds. The measured levels of PCBs and PAHs are also below the limits. Other compounds identified in the C&DW leachates include phthalates and diphenylmethanol. The characterized C&DW aggregates show lower quality properties than natural aggregates but most samples showed to be environmentally safe. A continuous monitoring of the presence of heavy metals and organic compounds should be made to trial safe C&DW aggregates. C&DW aggregates provide a good economic and environmental alternative to natural aggregates.

Keywords: concrete preparation, construction and demolition waste, heavy metals, organic pollutants

Procedia PDF Downloads 359
3098 Growth of Struvite Crystals in Synthetic Urine Using Magnesium Nitrate

Authors: Reneiloe Seodigeng, John Kabuba, Hilary Rutto, Tumisang Seodigeng

Abstract:

Urine diversion toilets have become popular as a means of solving the challenges in sanitation. As a result, the source-separated urine must be adequately treated so that it can be disposed of safely and valuable struvite can be extracted for use as fertilizer. In this study, synthetic urine was prepared, and struvite crystallisation experiments carried out using magnesium nitrate. The effect of residence time on crystal growth was studied. At residence time of 10, 30 and 60 minutes, mean particle sizes were 17, 34 and 53 µm showing that with higher residence times, larger crystal sizes can be achieved. SEM analysis of the crystal showed that the resultant crystals had the typical morphology of struvite crystals.

Keywords: struvite, magnesium nitrate, crystallisation, urine treatment

Procedia PDF Downloads 161
3097 Effect of Fluidized Granular Activated Carbon for the Mitigation of Membrane Fouling in Wastewater Treatment

Authors: Jingwei Wang, Anthony G. Fane, Jia Wei Chew

Abstract:

The use of fluidized Granular Activated Carbon (GAC) as a means of mitigation membrane fouling in membrane bioreactors (MBRs) has received much attention in recent years, especially in anaerobic fluidized bed membrane bioreactors (AFMBRs). It has been affirmed that the unsteady-state tangential shear conferred by GAC fluidization on membrane surface suppressed the extent of membrane fouling with energy consumption much lower than that of bubbling (i.e., air sparging). In a previous work, the hydrodynamics of the fluidized GAC particles were correlated with membrane fouling mitigation effectiveness. Results verified that the momentum transfer from particle to membrane held a key in fouling mitigation. The goal of the current work is to understand the effect of fluidized GAC on membrane critical flux. Membrane critical flux values were measured by a vertical Direct Observation Through the Membrane (DOTM) setup. The polystyrene particles (known as latex particles) with the particle size of 5 µm were used as model foulant thus to give the number of the foulant on the membrane surface. Our results shed light on the positive effect of fluidized GAC enhancing the critical membrane flux by an order-of-magnitude as compared to that of liquid shear alone. Membrane fouling mitigation was benefitted by the increasing of power input.

Keywords: membrane fouling mitigation, liquid-solid fluidization, critical flux, energy input

Procedia PDF Downloads 407
3096 Effect of Several Soil Amendments on Water Quality in Mine Soils: Leaching Columns

Authors: Carmela Monterroso, Marc Romero-Estonllo, Carlos Pascual, Beatriz Rodríguez-Garrido

Abstract:

The mobilization of heavy metals from polluted soils causes their transfer to natural waters, with consequences for ecosystems and human health. Phytostabilization techniques are applied to reduce this mobility, through the establishment of a vegetal cover and the application of soil amendments. In this work, the capacity of different organic amendments to improve water quality and reduce the mobility of metals in mine-tailings was evaluated. A field pilot test was carried out with leaching columns installed on an old Cu mine ore (NW of Spain) which forms part of the PhytoSUDOE network of phytomanaged contaminated field sites (PhytoSUDOE/ Phy2SUDOE Projects (SOE1/P5/E0189 and SOE4/P5/E1021)). Ten columns (1 meter high by 25 cm in diameter) were packed with untreated mine tailings (control) or those treated with organic amendments. Applied amendments were based on different combinations of municipal wastes, bark chippings, biomass fly ash, and nanoparticles like aluminum oxides or ferrihydrite-type iron oxides. During the packing of the columns, rhizon-samplers were installed at different heights (10, 20, and 50 cm) from the top, and pore water samples were obtained by suction. Additionally, in each column, a bottom leachate sample was collected through a valve installed at the bottom of the column. After packing, the columns were sown with grasses. Water samples were analyzed for: pH and redox potential, using combined electrodes; salinity by conductivity meter: bicarbonate by titration, sulfate, nitrate, and chloride, by ion chromatography (Dionex 2000); phosphate by colorimetry with ammonium molybdate/ascorbic acid; Ca, Mg, Fe, Al, Mn, Zn, Cu, Cd, and Pb by flame atomic absorption/emission spectrometry (Perkin Elmer). Porewater and leachate from the control columns (packed with unamended mine tailings) were extremely acidic and had a high concentration of Al, Fe, and Cu. In these columns, no plant development was observed. The application of organic amendments improved soil conditions, which allowed the establishment of a dense cover of grasses in the rest of the columns. The combined effect of soil amendment and plant growth had a positive impact on water quality and reduced mobility of aluminum and heavy metals.

Keywords: leaching, organic amendments, phytostabilization, polluted soils

Procedia PDF Downloads 110
3095 Study of Biological Denitrification using Heterotrophic Bacteria and Natural Source of Carbon

Authors: Benbelkacem Ouerdia

Abstract:

Heterotrophic denitrification has been proven to be one of the most feasible processes for removing nitrate from wastewater and drinking water. In this process, heterotrophic bacteria use organic carbon for both growth and as an electron source. Underground water pollution by nitrates become alarming in Algeria. A survey carried out revealed that the nitrate concentration is in continual increase. Studies in some region revealed contamination exceeding the recommended permissible dose which is 50 mg/L. Worrying values in the regions of Mascara, Ouled saber, El Eulma, Bouira and Algiers are respectively 72 mg/L, 75 mg/L, 97 mg/L, 102 mg/L, and 158 mg/L. High concentration of nitrate in drinking water is associated with serious health risks. Research on nitrate removal technologies from municipal water supplies is increasing because of nitrate contamination. Biological denitrification enables the transformation of oxidized nitrogen compounds by a wide spectrum of heterotrophic bacteria into harmless nitrogen gas with accompanying carbon removal. Globally, denitrification is commonly employed in biological nitrogen removal processes to enhance water quality The study investigated the valorization of a vegetable residue as a carbon source (dates nodes) in water treatment using the denitrification process. Throughout the study, the effect of inoculums addition, pH, and initial concentration of nitrates was also investigated. In this research, a natural organic substance: dates nodes were investigated as a carbon source in the biological denitrification of drinking water. This material acts as a solid substrate and bio-film carrier. The experiments were carried out in batch processes. Complete denitrification was achieved varied between 80 and 100% according to the type of process used. It was found that the nitrate removal rate based on our results, we concluded that the removal of organic matter and nitrogen compounds depended mainly on the initial concentration of nitrate. The effluent pH was mainly affected by the C/N ratio, where a decrease increases pH.

Keywords: biofilm, carbon source, dates nodes, heterotrophic denitrification, nitrate, nitrite

Procedia PDF Downloads 484
3094 Valorization of Dates Nodes as a Carbon Source Using Biological Denitrification

Authors: Ouerdia Benbelkacem Belouanas

Abstract:

Heterotrophic denitrification has been proven to be one of the most feasible processes for removing nitrate from waste water and drinking water. In this process, heterotrophic bacteria use organic carbon for both growth and as an electron source. Underground water pollution by nitrates become alarming in Algeria. A survey carried out revealed that the nitrate concentration is in continual increase. Studies in some region revealed contamination exceeding the recommended permissible dose which is 50 mg/L. Worrying values in the regions of Mascara, Ouled saber, El Eulma, Bouira and Algiers are respectively 72 mg/L, 75 mg/L, 97 mg/L, 102 mg/L, and 158 mg/L. High concentration of nitrate in drinking water is associated with serious health risks. Research on nitrate removal technologies from municipal water supplies is increasing because of nitrate contamination. Biological denitrification enables transformation of oxidized nitrogen compounds by a wide spectrum of heterotrophic bacteria into harmless nitrogen gas with accompanying carbon removal. Globally, denitrification is commonly employed in biological nitrogen removal processes to enhance water quality. The study investigated the valorization of a vegetable residue as a carbon source (dates nodes) in water treatment using the denitrification process. Throughout the study, the effect of inoculums addition, pH, and initial concentration of nitrates was also investigated. In this research, a natural organic substance: dates nodes were investigated as a carbon source in the biological denitrification of drinking water. This material acts as a solid substrate and bio-film carrier. The experiments were carried out in batch processes. Complete denitrification was achieved varied between 80 and 100% according to the type of process used. It was found that the nitrate removal rate based on our results, we concluded that the removal of organic matter and nitrogen compounds depended mainly on initial concentration of nitrate. The effluent pH was mainly affected by the C/N ratio, where a decrease increases pH.

Keywords: biofilm, carbon source, dates nodes, heterotrophic denitrification, nitrate, nitrite

Procedia PDF Downloads 419
3093 Risks of Traditional Practices: Chemical and Health Assessment of Bakhour

Authors: Yehya Elsayed, Sarah Dalibalta, Fareedah Alqtaishat, Ioline Gomes, Nagelle Fernandes

Abstract:

Bakhour or Arabian incense is traditionally used to perfume houses, shops and clothing as part of cultural or religious practices in several Middle Eastern countries. Conventionally, Bakhour consists of a mixture of natural ingredients such as chips of agarwood (oud), musk and sandalwoods that are soaked in scented oil. Bakhour is usually burned by charcoal or by using gas or electric burners to produce the scented smoke. It is necessary to evaluate the impact of such practice on human health and environment especially that the burning of Bakhour is usually done on a regular basis and in closed areas without proper ventilation. Although significant amount of research has been reported in scientific literature on the chemical analysis of various types of incense smoke, unfortunately only very few of them focused specifically on the health impacts of Bakhour. Raw Bakhour samples, their smoke emissions and the ash residue were analyzed to assess the existence of toxic ingredients and their possible influence on health and the environment. Three brands of Bakhour samples were analyzed for the presence of harmful heavy metals and organic compounds. Thermal Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to identify organic compounds while Inductively Coupled Plasma (ICP) and Scanning Electron Microscope-Energy Dispersive X-Ray Spectrometer (SEM-EDS) were used to analyze the presence of toxic and heavy metals. Organic compounds from the smoke were collected on specific tenax and activated carbon adsorption tubes. More than 850 chemical compounds were identified. The presence of 19 carcinogens, 23 toxins and 173 irritants were confirmed. Additionally, heavy metals were detected in amounts similar to those present in cigarettes. However, it was noticed that many of the detected compounds in the smoke lacked clinical studies on their health effects which shows the need for further clinical studies to be devoted to this area of study.

Keywords: Bakhour, incense smoke, pollution, indoor environment, health risk, chemical analysis

Procedia PDF Downloads 428
3092 Chemical and Health Assessment of Bakhour: Risks of Traditional Practices

Authors: Yehya Elsayed, Sarah Dalibalta, Fareedah Alqtaishat, Ioline Gomes, Nagelle Fernandes

Abstract:

Bakhour, or Arabian incense, is traditionally used to perfume houses, shops and clothing as part of cultural or religious practices in several Middle Eastern countries. Conventionally, Bakhour consists of a mixture of natural ingredients such as chips of agarwood (oud), musk and sandalwoods that are soaked in scented oil. Bakhour is usually burned by charcoal or by using gas or electric burners to produce the scented smoke. It is necessary to evaluate the impact of such practice on human health and environment especially that the burning of Bakhour is usually done on a regular basis and in closed areas without proper ventilation. Although significant amount of research has been reported in scientific literature on the chemical analysis of various types of incense smoke, unfortunately, only very few of them focused specifically on the health impacts of Bakhour. Raw Bakhour samples, their smoke emissions and the ash residue were analyzed to assess the existence of toxic ingredients and their possible influence on health and the environment. Three brands of Bakhour samples were analyzed for the presence of harmful heavy metals and organic compounds. Thermal Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to identify organic compounds while Inductively Coupled Plasma (ICP) and Scanning Electron Microscope-Energy Dispersive X-Ray Spectrometer (SEM-EDS) were used to analyze the presence of toxic and heavy metals.. Organic compounds from the smoke were collected on specific tenax and activated carbon adsorption tubes. More than 850 chemical compounds were identified. The presence of 19 carcinogens, 23 toxins, and 173 irritants were confirmed. Additionally, heavy metals were detected in amounts similar to those present in cigarettes. However, it was noticed that many of the detected compounds in the smoke lacked clinical studies on their health effects which shows the need for further clinical studies to be devoted to this area of study.

Keywords: bakhour, incense smoke, pollution, indoor environment, health risk, chemical analysis

Procedia PDF Downloads 293
3091 Suboptimal Retiree Allocations with Housing

Authors: Asiye Aydilek, Harun Aydilek

Abstract:

We investigate the costs of various suboptimal allocations in housing, consumption, bond and stock holdings of a retiree in a setting with recursive utility, considering the extensive empirical evidence that investors make suboptimal decisions in different ways. We find that suboptimal stock holdings impose only modest costs on the retiree. This may have a merit in explaining the limited stock investment in the data. The cost of suboptimal bond holdings is higher than that of stocks, but still small. This may partially explain why many more people hold bonds compared to stocks. We find that positive deviations from the optimal level are less costly relative to the negative ones in suboptimal housing allocations. This may help us to clarify why the elderly are over consuming housing, as seen in the housing data. The cost of suboptimal consumption is quite high and the highest of all. Our paper suggests that, in terms of welfare, the decisions of how much of liquid wealth to use for consumption and for saving are more important than the decision about the composition of liquid savings. Suboptimal stock holdings are twice more costly in power utility and suboptimal bond holdings are twenty times more costly in recursive utility. Recursive utility is superior to power utility in terms of rationalizing many people's preference for bonds instead of stocks in investment.

Keywords: housing, recursive utility, retirement, suboptimal decisions, welfare cost

Procedia PDF Downloads 317
3090 Electro-Oxidation of Glycerol Using Nickel Deposited Carbon Ceramic Electrode and Product Analysis Using High Performance Liquid Chromatography

Authors: Mulatu Kassie Birhanu

Abstract:

Electro-oxidation of glycerol is an important process to convert the less price glycerol into other expensive (essential) and energy-rich chemicals. In this study, nickel was electro-deposited on laboratory-made carbon ceramic electrode (CCE) substrate using electrochemical techniques that is cyclic voltammetry (CV) to prepare an electro-catalyst (Ni/CCE) for electro-oxidation of glycerol. Carbon ceramic electrode was prepared from graphite and methyl tri-methoxy silane (MTMOS) through the processes called hydrolysis and condensation with methanol in acidic media (HCl) by a sol-gel technique. Physico-chemical characterization of bare CCE and modified (deposited) CCE (Ni/CCE) was measured and evaluated by Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). Electro-oxidation of glycerol was performed in 0.1 M glycerol in alkaline media (0.5 M NaOH). High-Performance Liquid Chromatography (HPLC) technique was used to identify and determine the concentration of glycerol, reaction intermediates and oxidized products of glycerol after its electro-oxidation is performed. The conversion (%) of electro-oxidation of glycerol during 9-hour oxidation was 73% and 36% at 1.8V and 1.6V vs. RHE, respectively. Formate, oxalate, glycolate and glycerate are the main oxidation products of glycerol with selectivity (%) of 75%, 8.6%, 1.1% and 0.95 % at 1.8 V vs. RHE and 55.4%, 2.2%, 1.0% and 0.6% at 1.6 V vs. RHE respectively. The result indicates that formate is the main product in the electro-oxidation of glycerol on Ni/CCE using the indicated applied potentials.

Keywords: carbon-ceramic electrode, electrodeposition, electro-oxidation, Methyltrimethoxysilane

Procedia PDF Downloads 238
3089 Influence of Dietary Inclusion of Butyric Acids, Calcium Formate, Organic Acids and Its Salts on Rabbits Productive Performance, Carcass Traits and Meat Quality

Authors: V. Viliene, A. Raceviciute-Stupeliene, V. Sasyte, V. Slausgalvis, R. Gruzauskas, J. Al-Saifi

Abstract:

Animal nutritionists and scientists have searched for alternative measures to improve the production. One of such alternative is use of organic acids as feed additive in animal nutrition. The study was conducted to investigate the impact of butyric acids, calcium formate, organic acids, and its salts (BCOS) additives on rabbit’s productive performance, carcass traits and meat quality. The study was conducted with 14 Californian breed rabbits. The rabbits were assigned to two treatment groups (seven rabbits per each treatment group). The dietary treatments were 1) control diet, 2) diet supplemented with a mixture BCOS - 2 kg/t of feed. Growth performance characteristics (body weight, daily weight gain, daily feed intake, feed conversion ratio, mortality) were evaluated. Rabbits were slaughtered; carcass characteristics and meat quality were evaluated. Samples loin and hind leg meat were analysed to determine carcass characteristics, pH and colour measurements, cholesterol, and malonyldialdehyde (MDA) content in loin and hind leg meat. Differences between treatments were significant for body weight (1.30 vs. 1.36 kg; P<0.05), daily weight gain (16.60 vs. 17.85 g; P<0.05), and daily feed intake (78.25 vs. 80.58 g; P<0.05) for control and experimental group respectively for the entire experimental period (from 28–77 days old). No significant differences were found in feed conversion ratio and mortality. The feed additives insertion in the diets did not significantly influence the carcass yield or the proportions of the various carcass parts and organs. Differences between treatments were significant for pH value after 48h in loin (5.86 vs. 5.74; P<0.05), hind leg meat (6.62 vs. 6.65; P<0.05), more intense colour b* of loin (5.57 vs. 6.06; P<0.05), less intense colour a* (14.99 vs. 13.15; P<0.05) in hind leg meat. Cholesterol content in hind leg meat decreased by 17.67 mg/100g compared to control group (P<0.05). After storage for three months, MDA concentration decreased in loin and hind leg meat by 0.3 μmol/kg and 0.26 μmol/kg respectively compared to that of the control group (P<0.05). The results of this study suggest that BCOS could potentially be used in rabbit nutrition with consequent benefits on the rabbits’ productivity and nutritional quality of rabbit meat for consumers.

Keywords: butyric acids, Ca formate, meat quality, organic acids salts, rabbits, productivity

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3088 Organic Farming Profitability: Evidence from South Korea

Authors: Saem Lee, Thanh Nguyen, Hio-Jung Shin, Thomas Koellner

Abstract:

Land-use management has an influence on the provision of ecosystem service in dynamic, agricultural landscapes. Agricultural land use is important for maintaining the productivity and sustainability of agricultural ecosystems. However, in Korea, intensive farming activities in this highland agricultural zone, the upper stream of Soyang has led to contaminated soil caused by over-use pesticides and fertilizers. This has led to decrease in water and soil quality, which has consequences for ecosystem services and human wellbeing. Conventional farming has still high percentage in this area and there is no special measure to prevent low water quality caused by farming activities. Therefore, the adoption of environmentally friendly farming has been considered one of the alternatives that lead to improved water quality and increase in biomass production. Concurrently, farm households with environmentally friendly farming have occupied still low rates. Therefore, our research involved a farm household survey spanning conventional farming, the farm in transition and organic farming in Soyang watershed. Another purpose of our research was to compare economic advantage of the farmers adopting environmentally friendly farming and non-adaptors and to investigate the different factors by logistic regression analysis with socio-economic and benefit-cost ratio variables. The results found that farmers with environmentally friendly farming tended to be younger than conventional farming and farmer in transition. They are similar in terms of gender which was predominately male. Farmers with environmentally friendly farming were more educated and had less farming experience than conventional farming and farmer in transition. Based on the benefit-cost analysis, total costs that farm in transition farmers spent for one year are about two times as much as the sum of costs in environmentally friendly farming. The benefit of organic farmers was assessed with 2,800 KRW per household per year. In logistic regression, the factors having statistical significance are subsidy and district, residence period and benefit-cost ratio. And district and residence period have the negative impact on the practice of environmentally friendly farming techniques. The results of our research make a valuable contribution to provide important information to describe Korean policy-making for agricultural and water management and to consider potential approaches to policy that would substantiate ways beneficial for sustainable resource management.

Keywords: organic farming, logistic regression, profitability, agricultural land-use

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3087 Active Filtration of Phosphorus in Ca-Rich Hydrated Oil Shale Ash Filters: The Effect of Organic Loading and Form of Precipitated Phosphatic Material

Authors: Päärn Paiste, Margit Kõiv, Riho Mõtlep, Kalle Kirsimäe

Abstract:

For small-scale wastewater management, the treatment wetlands (TWs) as a low cost alternative to conventional treatment facilities, can be used. However, P removal capacity of TW systems is usually problematic. P removal in TWs is mainly dependent on the physico–chemical and hydrological properties of the filter material. Highest P removal efficiency has been shown trough Ca-phosphate precipitation (i.e. active filtration) in Ca-rich alkaline filter materials, e.g. industrial by-products like hydrated oil shale ash (HOSA), metallurgical slags. In this contribution we report preliminary results of a full-scale TW system using HOSA material for P removal for a municipal wastewater at Nõo site, Estonia. The main goals of this ongoing project are to evaluate: a) the long-term P removal efficiency of HOSA using real waste water; b) the effect of high organic loading rate; c) variable P-loading effects on the P removal mechanism (adsorption/direct precipitation); and d) the form and composition of phosphate precipitates. Onsite full-scale experiment with two concurrent filter systems for treatment of municipal wastewater was established in September 2013. System’s pretreatment steps include septic tank (2 m2) and vertical down-flow LECA filters (3 m2 each), followed by horizontal subsurface HOSA filters (effective volume 8 m3 each). Overall organic and hydraulic loading rates of both systems are the same. However, the first system is operated in a stable hydraulic loading regime and the second in variable loading regime that imitates the wastewater production in an average household. Piezometers for water and perforated sample containers for filter material sampling were incorporated inside the filter beds to allow for continuous in-situ monitoring. During the 18 months of operation the median removal efficiency (inflow to outflow) of both systems were over 99% for TP, 93% for COD and 57% for TN. However, we observed significant differences in the samples collected in different points inside the filter systems. In both systems, we observed development of preferred flow paths and zones with high and low loadings. The filters show formation and a gradual advance of a “dead” zone along the flow path (zone with saturated filter material characterized by ineffective removal rates), which develops more rapidly in the system working under variable loading regime. The formation of the “dead” zone is accompanied by the growth of organic substances on the filter material particles that evidently inhibit the P removal. Phase analysis of used filter materials using X-ray diffraction method reveals formation of minor amounts of amorphous Ca-phosphate precipitates. This finding is supported by ATR-FTIR and SEM-EDS measurements, which also reveal Ca-phosphate and authigenic carbonate precipitation. Our first experimental results demonstrate that organic pollution and loading regime significantly affect the performance of hydrated ash filters. The material analyses also show that P is incorporated into a carbonate substituted hydroxyapatite phase.

Keywords: active filtration, apatite, hydrated oil shale ash, organic pollution, phosphorus

Procedia PDF Downloads 274
3086 Response Regimes and Vibration Mitigation in Equivalent Mechanical Model of Strongly Nonlinear Liquid Sloshing

Authors: Maor Farid, Oleg Gendelman

Abstract:

Equivalent mechanical model of liquid sloshing in partially-filled cylindrical vessel is treated in the cases of free oscillations and of horizontal base excitation. The model is designed to cover both the linear and essentially nonlinear sloshing regimes. The latter fluid behaviour might involve hydraulic impacts interacting with the inner walls of the tank. These impulsive interactions are often modeled by high-power potential and dissipation functions. For the sake of analytical description, we use the traditional approach by modeling the impacts with velocity-dependent restitution coefficient. This modelling is similar to vibro-impact nonlinear energy sink (VI NES) which was recently explored for its vibration mitigation performances and nonlinear response regimes. Steady-state periodic regimes and chaotic strongly modulated responses (CSMR) are detected. Those dynamical regimes were described by the system's slow motion on the slow invariant manifold (SIM). There is a good agreement between the analytical results and numerical simulations. Subsequently, Finite-Element (FE) method is used to determine and verify the model parameters and to identify dominant dynamical regimes, natural modes and frequencies. The tank failure modes are identified and critical locations are identified. Mathematical relation is found between degrees-of-freedom (DOFs) motion and the mechanical stress applied in the tank critical section. This is the prior attempt to take under consideration large-amplitude nonlinear sloshing and tank structure elasticity effects for design, regulation definition and resistance analysis purposes. Both linear (tuned mass damper, TMD) and nonlinear (nonlinear energy sink, NES) passive energy absorbers contribution to the overall system mitigation is firstly examined, in terms of both stress reduction and time for vibration decay.

Keywords: nonlinear energy sink (NES), reduced-order modelling, liquid sloshing, vibration mitigation, vibro-impact dynamics

Procedia PDF Downloads 146
3085 Functional Nanomaterials for Environmental Applications

Authors: S. A. M. Sabrina, Gouget Lammel, Anne Chantal, Chazalviel, Jean Noël, Ozanam François, Etcheberry Arnaud, Tighlit Fatma Zohra, B. Samia, Gabouze Noureddine

Abstract:

The elaboration and characterization of hybrid nano materials give rise to considerable interest due to the new properties that arising. They are considered as an important category of new materials having innovative characteristics by combining the specific intrinsic properties of inorganic compounds (semiconductors) with the grafted organic species. This open the way to improved properties and spectacular applications in various and important fields, especially in the environment. In this work, nano materials based-semiconductors were elaborated by chemical route. The obtained surfaces were grafted with organic functional groups. The functionalization process was optimized in order to confer to the hybrid nano material a good stability as well as the right properties required for the subsequent applications. Different characterization techniques were used to investigate the resulting nano structures, such as SEM, UV-Visible, FTIR, Contact angle and electro chemical measurements. Finally, applications were envisaged in environmental area. The elaborated nano structures were tested for the detection and the elimination of pollutants.

Keywords: hybrid materials, porous silicon, peptide, metal detection

Procedia PDF Downloads 499
3084 Geochemical Study of Natural Bitumen, Condensate and Gas Seeps from Sousse Area, Central Tunisia

Authors: Belhaj Mohamed, M. Saidi, N. Boucherab, N. Ouertani, I. Bouazizi, M. Ben Jrad

Abstract:

Natural hydrocarbon seepage has helped petroleum exploration as a direct indicator of gas and/or oil subsurface accumulations. Surface macro-seeps are generally an indication of a fault in an active Petroleum Seepage System belonging to a Total Petroleum System. This paper describes a case study in which multiple analytical techniques were used to identify and characterize trace petroleum-related hydrocarbons and other volatile organic compounds in groundwater samples collected from Sousse aquifer (Central Tunisia). The analytical techniques used for analyses of water samples included gas chromatography-mass spectrometry (GC-MS), capillary GC with flame-ionization detection, Compund Specific Isotope Analysis, Rock Eval Pyrolysis. The objective of the study was to confirm the presence of gasoline and other petroleum products or other volatile organic pollutants in those samples in order to assess the respective implication of each of the potentially responsible parties to the contamination of the aquifer. In addition, the degree of contamination at different depths in the aquifer was also of interest. The oil and gas seeps have been investigated using biomarker and stable carbon isotope analyses to perform oil-oil and oil-source rock correlations. The seepage gases are characterized by high CH4 content, very low δ13CCH4 values (-71,9 ‰) and high C1/C1–5 ratios (0.95–1.0), light deuterium–hydrogen isotope ratios (-198 ‰) and light δ13CC2 and δ13CCO2 values (-23,8‰ and-23,8‰ respectively) indicating a thermogenic origin with the contribution of the biogenic gas. An organic geochemistry study was carried out on the more ten oil seep samples. This study includes light hydrocarbon and biomarkers analyses (hopanes, steranes, n-alkanes, acyclic isoprenoids, and aromatic steroids) using GC and GC-MS. The studied samples show at least two distinct families, suggesting two different types of crude oil origins: the first oil seeps appears to be highly mature, showing evidence of chemical and/or biological degradation and was derived from a clay-rich source rock deposited in suboxic conditions. It has been sourced mainly by the lower Fahdene (Albian) source rocks. The second oil seeps was derived from a carbonate-rich source rock deposited in anoxic conditions, well correlated with the Bahloul (Cenomanian-Turonian) source rock.

Keywords: biomarkers, oil and gas seeps, organic geochemistry, source rock

Procedia PDF Downloads 443
3083 Role of Natural Products in Drug Discovery of Anti-Biotic and Anti-Cancer Agents

Authors: Sunil Kumar

Abstract:

For many years, small organic molecules derived naturally from microbes and plants have delivered a number of expedient therapeutic drug agents. The search for naturally occurring lead compounds has continued in recent years as well, with the constituents of marine flora and fauna along with those of telluric microorganisms and plants being investigated for their anti-bacterial and anti-cancer activities. It has been observed that such promising lead molecules incline to promptly generate substantial attention among scientists like synthetic organic chemists and biologists. Subsequently, the availability of a given precious natural product sample may be enriched, and it may be possible to determine a preliminary idea of structure-activity relationships to develop synthetic analogues. For instance, anti-tumor drug topotecan is a synthetic chemical compound similar in chemical structure to camptothecin which is found in extracts of Camptotheca acuminate. Similarly, researchers at AstraZeneca discovered anti-biotic pyrrolamide through a fragment-based lead generation approach from kibdelomycin, which is isolated from Staphylococcus aureuss.

Keywords: anticancer, antibiotic, lead molecule, natural product, synthetic analogues

Procedia PDF Downloads 152
3082 High Pressure Multiphase Flow Experiments: The Impact of Pressure on Flow Patterns Using an X-Ray Tomography Visualisation System

Authors: Sandy Black, Calum McLaughlin, Alessandro Pranzitelli, Marc Laing

Abstract:

Multiphase flow structures of two-phase multicomponent fluids were experimentally investigated in a large diameter high-pressure pipeline up to 130 bar at TÜV SÜD’s National Engineering Laboratory Advanced Multiphase Facility. One of the main objectives of the experimental test campaign was to evaluate the impact of pressure on multiphase flow patterns as much of the existing information is based on low-pressure measurements. The experiments were performed in a horizontal and vertical orientation in both 4-inch and 6-inch pipework using nitrogen, ExxsolTM D140 oil, and a 6% aqueous solution of NaCl at incremental pressures from 10 bar to 130 bar. To visualise the detailed structure of the flow of the entire cross-section of the pipe, a fast response X-ray tomography system was used. A wide range of superficial velocities from 0.6 m/s to 24.0 m/s for gas and 0.04 m/s and 6.48 m/s for liquid was examined to evaluate different flow regimes. The results illustrated the suppression of instabilities between the gas and the liquid at the measurement location and that intermittent or slug flow was observed less frequently as the pressure was increased. CFD modellings of low and high-pressure simulations were able to successfully predict the likelihood of intermittent flow; however, further tuning is necessary to predict the slugging frequency. The dataset generated is unique as limited datasets exist above 100 bar and is of considerable value to multiphase flow specialists and numerical modellers.

Keywords: computational fluid dynamics, high pressure, multiphase, X-ray tomography

Procedia PDF Downloads 143
3081 Feasibility of Washing/Extraction Treatment for the Remediation of Deep-Sea Mining Trailings

Authors: Kyoungrean Kim

Abstract:

Importance of deep-sea mineral resources is dramatically increasing due to the depletion of land mineral resources corresponding to increasing human’s economic activities. Korea has acquired exclusive exploration licenses at four areas which are the Clarion-Clipperton Fracture Zone in the Pacific Ocean (2002), Tonga (2008), Fiji (2011) and Indian Ocean (2014). The preparation for commercial mining of Nautilus minerals (Canada) and Lockheed martin minerals (USA) is expected by 2020. The London Protocol 1996 (LP) under International Maritime Organization (IMO) and International Seabed Authority (ISA) will set environmental guidelines for deep-sea mining until 2020, to protect marine environment. In this research, the applicability of washing/extraction treatment for the remediation of deep-sea mining tailings was mainly evaluated in order to present preliminary data to develop practical remediation technology in near future. Polymetallic nodule samples were collected at the Clarion-Clipperton Fracture Zone in the Pacific Ocean, then stored at room temperature. Samples were pulverized by using jaw crusher and ball mill then, classified into 3 particle sizes (> 63 µm, 63-20 µm, < 20 µm) by using vibratory sieve shakers (Analysette 3 Pro, Fritsch, Germany) with 63 µm and 20 µm sieve. Only the particle size 63-20 µm was used as the samples for investigation considering the lower limit of ore dressing process which is tens to 100 µm. Rhamnolipid and sodium alginate as biosurfactant and aluminum sulfate which are mainly used as flocculant were used as environmentally friendly additives. Samples were adjusted to 2% liquid with deionized water then mixed with various concentrations of additives. The mixture was stirred with a magnetic bar during specific reaction times and then the liquid phase was separated by a centrifugal separator (Thermo Fisher Scientific, USA) under 4,000 rpm for 1 h. The separated liquid was filtered with a syringe and acrylic-based filter (0.45 µm). The extracted heavy metals in the filtered liquid were then determined using a UV-Vis spectrometer (DR-5000, Hach, USA) and a heat block (DBR 200, Hach, USA) followed by US EPA methods (8506, 8009, 10217 and 10220). Polymetallic nodule was mainly composed of manganese (27%), iron (8%), nickel (1.4%), cupper (1.3 %), cobalt (1.3%) and molybdenum (0.04%). Based on remediation standards of various countries, Nickel (Ni), Copper (Cu), Cadmium (Cd) and Zinc (Zn) were selected as primary target materials. Throughout this research, the use of rhamnolipid was shown to be an effective approach for removing heavy metals in samples originated from manganese nodules. Sodium alginate might also be one of the effective additives for the remediation of deep-sea mining tailings such as polymetallic nodules. Compare to the use of rhamnolipid and sodium alginate, aluminum sulfate was more effective additive at short reaction time within 4 h. Based on these results, sequencing particle separation, selective extraction/washing, advanced filtration of liquid phase, water treatment without dewatering and solidification/stabilization may be considered as candidate technologies for the remediation of deep-sea mining tailings.

Keywords: deep-sea mining tailings, heavy metals, remediation, extraction, additives

Procedia PDF Downloads 155
3080 Transfer Rate of Organic Water Contaminants through a Passive Sampler Membrane of Polyethersulfone (PES)

Authors: Hamidreza Sharifan, Audra Morse

Abstract:

Accurate assessments of contaminant concentrations based on traditional grab sampling methods are not always possible. Passive samplers offer an attractive alternative to traditional sampling methods that overcomes these limitations. The POCIS approach has been used as a screening tool for determining the presence/absence, possible sources and relative amounts of organic compounds at field sites. The objective for the present research is on mass transfer of five water contaminants (atrazine, caffeine, bentazon, ibuprofen, atenolol) through the Water Boundary Layer (WBL) and membrane. More specific objectives followed by establishing a relationship between the sampling rate and water solubility of the compounds, as well as comparing the molecular weight of the compounds and concentration of the compounds at the time of equilibrium. To determine whether water boundary layer effects transport rate through the membrane is another main objective in this paper. After GC mass analysis of compounds, regarding the WBL effect in this experiment, Sherwood number for the experimental tank developed. A close relationship between feed concentration of compound and sampling rate has been observed.

Keywords: passive sampler, water contaminants, PES-transfer rate, contaminant concentrations

Procedia PDF Downloads 455
3079 Surface Morphology Refinement and Laves Phase Control of Inconel 718 during Plasma Arc Additive Manufacturing by Alternating Magnetic Field

Authors: Yi Zheng

Abstract:

Improving formability and mechanical properties have always been one of the challenges in the field of additive manufacturing (AM) of nickel-based superalloys. In this work, the effect of a coaxially coupled alternating magnetic field (AMF) on surface morphology and mechanical properties of plasma arc-based additive manufactured Inconel 718 deposit were investigated. Results show that the Lorentz force induced by AMF strongly alters the flow behavior of the plasma jet and the molten pool, suppressing the tendency of the liquid metal in the molten pool to flow down on the two sides face of the deposit, which in turn remarkably improved the surface accuracy of the thin-walled deposit. Furthermore, the electromagnetic stirring induced by AMF can effectively enhance the convection between the dendrites, which could not only contribute to the formation of finer dendrites but also alleviate the enrichment of the elements (i.e., Nb and Mo) at the solid-liquid interface and inhibits the precipitation of Laves phase. The smallest primary dendritic arm spacing (~13 μm) and lowest Laves phases area fraction (3.12%) were witnessed in the bottom region of the AMF-assisted deposit. The mechanical test confirmed that the deposit's micro-hardness and tensile properties were moderately improved compared with the counterpart without AMF.

Keywords: additive manufacturing, inconel 718, alternating magnetic field, laves phase

Procedia PDF Downloads 79
3078 Quantum Dots Incorporated in Biomembrane Models for Cancer Marker

Authors: Thiago E. Goto, Carla C. Lopes, Helena B. Nader, Anielle C. A. Silva, Noelio O. Dantas, José R. Siqueira Jr., Luciano Caseli

Abstract:

Quantum dots (QD) are semiconductor nanocrystals that can be employed in biological research as a tool for fluorescence imagings, having the potential to expand in vivo and in vitro analysis as cancerous cell biomarkers. Particularly, cadmium selenide (CdSe) magic-sized quantum dots (MSQDs) exhibit stable luminescence that is feasible for biological applications, especially for imaging of tumor cells. For these facts, it is interesting to know the mechanisms of action of how such QDs mark biological cells. For that, simplified models are a suitable strategy. Among these models, Langmuir films of lipids formed at the air-water interface seem to be adequate since they can mimic half a membrane. They are monomolecular films formed at liquid-gas interfaces that can spontaneously form when organic solutions of amphiphilic compounds are spread on the liquid-gas interface. After solvent evaporation, the monomolecular film is formed, and a variety of techniques, including tensiometric, spectroscopic and optic can be applied. When the monolayer is formed by membrane lipids at the air-water interface, a model for half a membrane can be inferred where the aqueous subphase serve as a model for external or internal compartment of the cell. These films can be transferred to solid supports forming the so-called Langmuir-Blodgett (LB) films, and an ampler variety of techniques can be additionally used to characterize the film, allowing for the formation of devices and sensors. With these ideas in mind, the objective of this work was to investigate the specific interactions of CdSe MSQDs with tumorigenic and non-tumorigenic cells using Langmuir monolayers and LB films of lipids and specific cell extracts as membrane models for diagnosis of cancerous cells. Surface pressure-area isotherms and polarization modulation reflection-absorption spectroscopy (PM-IRRAS) showed an intrinsic interaction between the quantum dots, inserted in the aqueous subphase, and Langmuir monolayers, constructed either of selected lipids or of non-tumorigenic and tumorigenic cells extracts. The quantum dots expanded the monolayers and changed the PM-IRRAS spectra for the lipid monolayers. The mixed films were then compressed to high surface pressures and transferred from the floating monolayer to solid supports by using the LB technique. Images of the films were then obtained with atomic force microscopy (AFM) and confocal microscopy, which provided information about the morphology of the films. Similarities and differences between films with different composition representing cell membranes, with or without CdSe MSQDs, was analyzed. The results indicated that the interaction of quantum dots with the bioinspired films is modulated by the lipid composition. The properties of the normal cell monolayer were not significantly altered, whereas for the tumorigenic cell monolayer models, the films presented significant alteration. The images therefore exhibited a stronger effect of CdSe MSQDs on the models representing cancerous cells. As important implication of these findings, one may envisage for new bioinspired surfaces based on molecular recognition for biomedical applications.

Keywords: biomembrane, langmuir monolayers, quantum dots, surfaces

Procedia PDF Downloads 196
3077 Effect of Capillary Forces on Wet Granular Avalanches

Authors: Ahmed Jarray, Vanessa Magnanimo, Stefan Luding

Abstract:

Granular avalanches are ubiquitous in nature and occur in numerous industrial processes associated with particulate systems. When a small amount of liquid is added to a pile of particles, pendular bridges form and the particles are attracted by capillary forces, creating complex structure and flow behavior. We have performed an extensive series of experiments to investigate the effect of capillary force and particle size on wet granular avalanches, and we established a methodology that ensures the control of the granular flow in a rotating drum. The velocity of the free surface and the angle of repose of the particles in the rotating drum are determined using particle tracking method. The capillary force between the particles is significantly reduced by making the glass beads hydrophobic via chemical silanization. We show that the strength of the capillary forces between two adjacent particles can be deliberately manipulated through surface modification of the glass beads, thus, under the right conditions; we demonstrate that the avalanche dynamics can be controlled. The results show that the avalanche amplitude decreases when increasing the capillary force. We also find that liquid-induced cohesion increases the width of the gliding layer and the dynamic angle of repose, however, it decreases the velocity of the free surface.

Keywords: avalanche dynamics, capillary force, granular material, granular flow

Procedia PDF Downloads 276
3076 Assessment of Bioaerosol and Microbial Volatile Organic Compounds in Different Sections of Library

Authors: Himanshu Lal, Bipasha Ghosh, Arun Srivastava

Abstract:

A pilot study of indoor air quality in terms of bioaerosol (fungus and bacteria) and few selective microbial volatile organic compounds (MVOCs) was carried out in different indoor sections of a library for two seasons, namely monsoon and post monsoon. Bioaerosol sampling was carried out using Anderson six stage viable sampler at a flow rate of 28.3 L/min while MVOCs were collected on activated charcoal tubes ORBOTM 90 Carboxen 564.Collected MVOCs were desorbed using carbon disulphide (CS2) and analysed by GC-FID. Microscopic identification for fungus was only carried out. Surface dust was collected by sterilised buds and cultured to identify fungal contaminants. Unlike bacterial size distribution, fungal bioaerosol concentration was found to be highest in the fourth stage in different sections of the library. In post monsoon season both fungal bioaerosol (710 to 3292cfu/m3) and bacterial bioaerosol (298 to 1475cfu/m3) were fund at much greater concentration than in monsoon. In monsoon season unlike post monsoon, I/O ratio for both the bioaerosol fractions was more than one. Rain washout could be the reason of lower outdoor concentration in monsoon season. On the contrary most of the MVOCs namely 1-hexene, 1-pentanol and 1-octen-3-ol were found in the monsoon season instead of post monsoon season with the highest being 1-hexene with 7.09µg/m3 concentration. Among the six identified fungal bioaerosol Aspergillus, Cladosporium and Penicillium were found in maximum concentration while Aspergillus niger, Curvuleria lunata, Cladosporium cladosporioides and Penicillium sp., was indentified in surface dust samples. According to regression analysis apart from environmental factors other factors also played an important role. Thus apart from outdoor infiltration and human sources, accumulated surface dust mostly on organic materials like books, wooden furniture and racks can be attributed to being one of the major sources of both fungal bioaerosols as well as MVOCs found in the library.

Keywords: bacteria, Fungi, indoor air, MVOCs

Procedia PDF Downloads 318