Search results for: dissolve oxygen
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1486

Search results for: dissolve oxygen

556 Compositional Dependence of Hydroxylated Indium-Oxide on the Reaction Rate of CO2/H2 Reduction

Authors: Joel Y. Y. Loh, Geoffrey A. Ozin, Charles A. Mims, Nazir P. Kherani

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A major goal in the emerging field of solar fuels is to realize an ‘artificial leaf’ – a material that converts light energy in the form of solar photons into chemical energy – using CO2 as a feedstock to generate useful chemical species. Enabling this technology will allow the greenhouse gas, CO2, emitted from energy and manufacturing production exhaust streams to be converted into valuable solar fuels or chemical products. Indium Oxide (In2O3) with surface hydroxyl (OH) groups have been shown to reduce CO2 in the presence of H2 to CO with a reaction rate of 15 μmol gcat−1 h−1. The likely mechanism is via a Frustrated Lewis Pair sites heterolytically splitting H2 to be absorbed and form protonic and hydric sites that can dissociate CO2. In this study, we investigate the dependence of oxygen composition of In2O3 on the CO2 reduction rate. In2O3-x films on quartz fiber paper were DC sputtered with an Indium target and varying O2/Ar plasma mixture. OH surface groups were then introduced by immersing the In2O3-x samples in KOH. We show that hydroxylated In2O3-x reduces more CO2 than non-hydroxylated groups and that a hydroxylated and higher O2/Ar ratio sputtered In2O3-x has a higher reaction rate of 45 μmol gcat-1 h-1. We show by electrical resistivity-temperature curves that H2 is adsorbed onto the surface of In2O3 whereas CO2 itself does not affect the indium oxide surface. We also present activation and ionization energy levels of the hydroxylated In2O3-x under vacuum, CO2 and H2 atmosphere conditions.

Keywords: solar fuels, photocatalysis, indium oxide nanoparticles, carbon dioxide

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555 Efficacy of Heart Failure Reversal Treatment Followed by 90 Days Follow up in Chronic Heart Failure Patients with Low Ejection Fraction

Authors: Rohit Sane, Snehal Dongre, Pravin Ghadigaonkar, Rahul Mandole

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The present study was designed to evaluate efficacy of heart failure reversal therapy (HFRT) that uses herbal procedure (panchakarma) and allied therapies, in chronic heart failure (CHF) patients with low ejection fraction. Methods: This efficacy study was conducted in CHF patients (aged: 25-65 years, ejection fraction (EF) < 30%) wherein HFRT (60-75 minutes) consisting of snehana (external oleation), swedana (passive heat therapy), hrudaydhara(concoction dripping treatment) and basti(enema) was administered twice daily for 7 days. During this therapy and next 30 days, patients followed the study dinarcharya and were prescribed ARJ kadha in addition to their conventional treatment. The primary endpoint of this study was evaluation of maximum aerobic capacity uptake (MAC) as assessed by 6-minute walk distance (6MWD) using Cahalins equation from baseline, at end of 7 day treatment, follow-up after 30 days and 90 days. EF was assessed by 2D Echo at baseline and after 30 days of follow-up. Results: CHF patients with < 30% EF (N=52, mean [SD] age: 58.8 [10.8], 85% men) were enrolled in the study. There was a 100% compliance to study therapy. A significant improvement was observed in MAC levels (7.11%, p =0.029), at end of 7 day therapy as compared to baseline. This improvement was maintained at two follow-up visits. Moreover, ejection fraction was observed to be increased by 6.38%, p=0,012 as compared to baseline at day 7 of the therapy. Conclusions: This 90 day follow up study highlights benefit of HFRT, as a part of maintenance treatment for CHF patients with reduced ejection fraction.

Keywords: chronic heart failure, functional capacity, heart failure reversal therapy, oxygen uptake, panchakarma

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554 Comparison of Microwave-Assisted and Conventional Leaching for Extraction of Copper from Chalcopyrite Concentrate

Authors: Ayfer Kilicarslan, Kubra Onol, Sercan Basit, Muhlis Nezihi Saridede

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Chalcopyrite (CuFeS2) is the most common primary mineral used for the commercial production of copper. The low dissolution efficiency of chalcopyrite in sulfate media has prevented an efficient industrial leaching of this mineral in sulfate media. Ferric ions, bacteria, oxygen and other oxidants have been used as oxidizing agents in the leaching of chalcopyrite in sulfate and chloride media under atmospheric or pressure leaching conditions. Two leaching methods were studied to evaluate chalcopyrite (CuFeS2) dissolution in acid media. First, the conventional oxidative acid leaching method was carried out using sulfuric acid (H2SO4) and potassium dichromate (K2Cr2O7) as oxidant at atmospheric pressure. Second, microwave-assisted acid leaching was performed using the microwave accelerated reaction system (MARS) for same reaction media. Parameters affecting the copper extraction such as leaching time, leaching temperature, concentration of H2SO4 and concentration of K2Cr2O7 were investigated. The results of conventional acid leaching experiments were compared to the microwave leaching method. It was found that the copper extraction obtained under high temperature and high concentrations of oxidant with microwave leaching is higher than those obtained conventionally. 81% copper extraction was obtained by the conventional oxidative acid leaching method in 180 min, with the concentration of 0.3 mol/L K2Cr2O7 in 0.5M H2SO4 at 50 ºC, while 93.5% copper extraction was obtained in 60 min with microwave leaching method under same conditions.

Keywords: extraction, copper, microwave-assisted leaching, chalcopyrite, potassium dichromate

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553 Measuring the Effect of Co-Composting Oil Sludge with Pig, Cow, Horse And Poultry Manures on the Degradation in Selected Polycyclic Aromatic Hydrocarbons Concentrations

Authors: Ubani Onyedikachi, Atagana Harrison Ifeanyichukwu, Thantsha Mapitsi Silvester

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Components of oil sludge (PAHs) are known cytotoxic, mutagenic and potentially carcinogenic compounds also bacteria and fungi have been found to degrade PAHs to innocuous compounds. This study is aimed at measuring the effect of pig, cow, horse and poultry manures on the degradation in selected PAHs present in oil sludge. Soil spiked with oil sludge was co-composted differently with each manure in a ratio of 2:1 (w/w) spiked soil: manure and wood-chips in a ratio of 2:1 (w/v) spiked soil: wood-chips. Control was set up similar as the one above but without manure. The mixtures were incubated for 10 months at room temperature. Compost piles were turned weekly and moisture level was maintained at between 50% and 70%. Moisture level, pH, temperature, CO2 evolution and oxygen consumption were measured monthly and the ash content at the end of experimentation. Highest temperature reached was 27.5 °C in all compost heaps, pH ranged from 5.5 to 7.8 and CO2 evolution was highest in poultry manure at 18.78μg/dwt/day. Microbial growth and activities were enhanced; bacteria identified were Bacillus, Arthrobacter and Staphylococcus species. Percentage reduction in PAHs was measured using automated soxhlet extractor with Dichloromethane coupled with gas chromatography/mass spectrometry (GC/MS). Results from PAH measurements showed reduction between 77% and 99%. Co-composting of spiked soils with animal manures enhanced the reduction in PAHs.

Keywords: animal manures, bioremediation, co-composting, oil refinery sludge, PAHs

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552 Pressure Relief in Prosthetic Sockets through Hole Implementation Using Different Materials

Authors: Gabi N. Nehme

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Below-knee amputees commonly experience asymmetrical gait patterns. It is generally believed that ischemia is related to the formation of pressure sores due to uneven distribution of forces. Micro-vascular responses can reveal local malnutrition. Changes in local skin blood supply under various external loading conditions have been studied for a number of years. Radionuclide clearance, photo-plethysmography, trans-cutaneous oxygen tension along with other studies showed that the blood supply would be influenced by the epidermal forces, and the rate and the amount of blood supply would decrease with increased epidermal loads being shear forces or normal forces. Several cases of socket designs were investigated using Finite Element Model (FEM) and Design of Experiment (DOE) to increase flexibility and minimize the pressure at the limb/socket interface using ultra high molecular weight polyethylene (UHMWPE) and polyamide 6 (PA6) or Duraform. The pressure reliefs at designated areas where reducing thickness is involved are seen to be critical in determination of amputees’ comfort and are very important to clinical applications. Implementing a hole between the Patellar Tendon (PT) and Distal Tibia (DT) would decrease stiffness and increase prosthesis range of motion where flexibility is needed. In addition, displacement and prosthetic energy storage increased without compromising mechanical efficiency and prosthetic design integrity.

Keywords: patellar tendon, distal tibia, prosthetic socket relief areas, hole implementation

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551 Effects of Live Yeast Supplementation to Reduce Oxidative Stress and Increase Lactation Performance of Dairy Cattle during the Summer Season

Authors: Ahmad Nawid Mirzad, Akira Goto, Takuto Endo, Hitoshi Ano, Hiromu Katamoto, Takenori Yamauchi

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The objective of this study was to evaluate the effects of live yeast supplementation on oxidative stress biomarker and antioxidant vitamin levels as well as lactation performance in Holstein Friesian cows during the summer season in Fukuoka prefecture. Sixteen lactating cows weighing 707.50 ± 13.09 kg (Mean ± SE) were used and randomly assigned to either supplemented (n = 8) or control (n = 8) group. The cows in supplemented group were administered with live yeast product at 10 g/d per cow from middle of July to middle of September for eight weeks. In treatment group, serum levels of derivatives of reactive oxygen metabolites (d-ROMs) were lower at week six. In addition, serum levels of glucose and retinol were higher at week eight and those of α-tocopherol were higher at week 2 in treatment group. During study period daily average milk yield decreased in both groups. Daily average milk yield 63 days after the onset of supplementation in treatment and control groups were 23.5 and 22.2 kg, respectively. The reduction rate of milk yield in treatment group tended to be lower (17.6 vs. 20.0%). These results suggest that live yeast supplementation may reduce oxidative stress and improve energy metabolism in lactating dairy cows during the summer season.

Keywords: cow, live yeast, milk, oxidative stress, summer season

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550 Erythrophagocytic Role of Mast Cells in vitro and in vivo during Oxidative Stress

Authors: Priyanka Sharma, Niti Puri

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Anemia develops when blood lacks enough healthy erythrocytes. Past studies indicated that anemia, inflammatory process, and oxidative stress are interconnected. Erythrocytes are continuously exposed to reactive oxygen species (ROS) during circulation, due to normal aerobic cellular metabolism and also pathology of inflammatory diseases. Systemic mastocytosis and genetic depletion of mast cells have been shown to affect anaemia. In the present study, we attempted to reveal whether mast cells have a direct role in clearance or erythrophagocytosis of normal or oxidatively damaged erythrocytes. Murine erythrocytes were treated with tert-butyl hydroperoxidase (t-BHP), an agent that induces oxidative damage and mimics in vivo oxidative stress. Normal and oxidatively damaged erythrocytes were labeled with carboxyfluorescein succinimidyl ester (CFSE) to track erythrophagocytosis. We show, for the first time, direct erythrophagocytosis of oxidatively damaged erythrocytes in vitro by RBL-2H3 mast cells as well as in vivo by murine peritoneal mast cells. Also, activated mast cells, as may be present in inflammatory conditions, showed a significant increase in the uptake of oxidatively damaged erythrocytes than resting mast cells. This suggests the involvement of mast cells in erythrocyte clearance during oxidative stress or inflammatory disorders. Partial inhibition of phagocytosis by various inhibitors indicated that this process may be controlled by several pathways. Hence, our study provides important evidence for involvement of mast cells in severe anemia due to inflammation and oxidative stress and might be helpful to circumvent the adverse anemic disorders.

Keywords: mast cells, anemia, erythrophagocytosis, oxidatively damaged erythrocytes

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549 Nucleophile Mediated Addition-Fragmentation Generation of Aryl Radicals from Aryl Diazonium Salts

Authors: Elene Tatunashvili, Bun Chan, Philippe E. Nashar, Christopher S. P. McErlean

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The reduction of aryl diazonium salts is one of the most efficient ways to generate aryl radicals for use in a wide range of transformations, including Sandmeyer-type reactions, Meerwein arylations of olefins and Gomberg-Bachmann-Hey arylations of heteroaromatic systems. The aryl diazonium species can be reduced electrochemically, by UV irradiation, inner-sphere and outer-sphere single electron transfer processes (SET) from metal salts, SET from photo-excited organic catalysts or fragmentation of adducts with weak bases (acetate, hydroxide, etc.). This paper details an approach for the metal-free reduction of aryl diazonium salts, which facilitates the efficient synthesis of various aromatic compounds under exceedingly mild reaction conditions. By measuring the oxidation potential of a number of organic molecules, a series of nucleophiles were identified that reduce aryl diazonium salts via the addition-fragmentation mechanism. This approach leads to unprecedented operational simplicity: The reactions are very rapid and proceed in the open air; there is no need for external irradiation or heating, and the process is compatible with a large number of radical reactions. We illustrate these advantages by using the addition-fragmentation strategy to regioselectively arylate a series of heterocyclic compounds, to synthesize ketones by arylation of silyl enol ethers, and to synthesize benzothiophene and phenanthrene derivatives by radical annulation reactions.

Keywords: diazonium salts, hantzsch esters, oxygen, radical reactions, synthetic methods

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548 Design, Construction And Validation Of A Simple, Low-cost Phi Meter

Authors: Gabrielle Peck, Ryan Hayes

Abstract:

The use of a phi meter allows for definition of equivalence ratio during a fire test. Previous phi meter designs have used expensive catalysts and had restricted portability due to the large furnace and requirement for pure oxygen. The new design of the phi meter did not require the use of a catalyst. The furnace design was based on the existing micro-scale combustion calorimetry (MCC) furnace and operating conditions based on the secondary oxidizer furnace used in the steady state tube furnace (SSTF). Preliminary tests were conducted to study the effects of varying furnace temperatures on combustion efficiency. The SSTF was chosen to validate the phi meter measurements as it can both pre-set and independently quantify the equivalence ratio during a test. The data were in agreement with the data obtained on the SSTF. It was also validated by a comparison of CO2 yields obtained from the SSTF oxidizer and those obtained by the phi meter. The phi meter designed and constructed in this work was proven to work effectively on a bench-scale. The phi meter was then used to measure the equivalence ratio on a series of large-scale ISO 9705 tests for numerous fire conditions. The materials used were a range of non-homogenous materials such as polyurethane. The measurements corresponded accurately to the data collected, showing the novel design can be used from bench to large-scale tests to measure equivalence ratio. This cheaper, more portable, safer and easier to use phi meter design will enable more widespread use and the ability to quantify fire conditions of tests, allowing for better understanding of flammability and smoke toxicity.

Keywords: phi meter, smoke toxicity, fire condition, ISO9705, novel equipment

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547 Bayesian Inference of Physicochemical Quality Elements of Tropical Lagoon Nokoué (Benin)

Authors: Hounyèmè Romuald, Maxime Logez, Mama Daouda, Argillier Christine

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In view of the very strong degradation of aquatic ecosystems, it is urgent to set up monitoring systems that are best able to report on the effects of the stresses they undergo. This is particularly true in developing countries, where specific and relevant quality standards and funding for monitoring programs are lacking. The objective of this study was to make a relevant and objective choice of physicochemical parameters informative of the main stressors occurring on African lakes and to identify their alteration thresholds. Based on statistical analyses of the relationship between several driving forces and the physicochemical parameters of the Nokoué lagoon, relevant Physico-chemical parameters were selected for its monitoring. An innovative method based on Bayesian statistical modeling was used. Eleven Physico-chemical parameters were selected for their response to at least one stressor and their threshold quality standards were also established: Total Phosphorus (<4.5mg/L), Orthophosphates (<0.2mg/L), Nitrates (<0.5 mg/L), TKN (<1.85 mg/L), Dry Organic Matter (<5 mg/L), Dissolved Oxygen (>4 mg/L), BOD (<11.6 mg/L), Salinity (7.6 .), Water Temperature (<28.7 °C), pH (>6.2), and Transparency (>0.9 m). According to the System for the Evaluation of Coastal Water Quality, these thresholds correspond to” good to medium” suitability classes, except for total phosphorus. One of the original features of this study is the use of the bounds of the credibility interval of the fixed-effect coefficients as local weathering standards for the characterization of the Physico-chemical status of this anthropized African ecosystem.

Keywords: driving forces, alteration thresholds, acadjas, monitoring, modeling, human activities

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546 Poly(Amidoamine) Dendrimer-Cisplatin Nanocomplex Mixed with Multifunctional Ovalbumin Coated Iron Oxide Nanoparticles for Immuno-Chemotherapeutics with M1 Polarization of Macrophages

Authors: Tefera Worku Mekonnen, Hiseh Chih Tsai

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Enhancement of drug efficacy is essential in cancer treatment. The immune stimulator ovalbumin (Ova)-coated citric acid (AC-)-stabilized iron oxide nanoparticles (AC-IO-Ova NPs) and enhanced permeability and retention (EPR) based tumor targeted 4.5 (4.5G) poly(amidoamine) dendrimer-cisplatin nanocomplex (4.5GDP-Cis-pt NC) were used for enhanced anticancer efficiency. The formations of 4.5GDP-Cis-pt NC, AC-IO, and AC-IO-Ova NPs have been examined by FTIR, X-ray diffraction, Raman, and X-ray photoelectron spectroscopy. The conjugation of cisplatin (Cis-pt) with 4.5GDP was confirmed using carbon NMR. The tumor-specific 4.5GDP-Cis-pt NC provided ~45% and 28% cumulative cisplatin release in 72 h at pH 6.5 and 7.4, respectively. A significant immune response with high TNF-α and IL-6 cytokine secretion was confirmed when the co-incubation of AC-IO-Ova with RAW 264.7 or HaCaT cells. AC-IO-Ova NP was biocompatible in different cell lines, even at a high concentration (200 µg mL−1). In contrast, AC-IO-Ova NPs mixed with 4.5GDP-Cis-pt NC (Cis-pt at 15 µg mL−1) significantly increased the cytotoxicity against the cancer cells, which is dose-dependent on the concentration of AC-IO-Ova NPs. The increased anticancer effects may be attributed to the generation of reactive oxygen species (ROS). Moreover, the efficiency of anticancer cells may be further assisted by induction of an innate immune response via M1 macrophage polarization due to the presence of AC-IO-Ova NPs. We provide a better synergestic chemoimmunotherapeutic strategy to enhance the efficiency of anticancer of cisplatin via chemotherapeutic agent 4.5GDP-Cis-pt NC and induction of proinflammatory cytokines to stimulate innate immunity through AC-IO-Ova NPs against tumors.

Keywords: cisplatin-release, iron oxide, ovalbumin, poly(amidoamine) dendrimer

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545 Cenomanian-Turonian Oceanic Anoxic Event, Palynofacies and Optical Kerogen Analysis in Abu Gharadig Basin, Egypt

Authors: Mohamed Ibrahim, Suzan Kholeif

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The Cenomanian-Turonian boundary was a ‘greenhouse’ period. The atmosphere at that time was characterized by high CO₂; in addition, there was the widespread deposition of organic-rich sediments anomalously rich in organic carbon. The sediments, palynological, total organic carbon (TOC), stable carbon and oxygen isotopes (δ¹³C, δ¹⁸O, organic) of the Cenomanian-Turonian Bahariya and basal Abu Roash formations at the southern Tethys margin were studied in two deep wells (AG5 and AG-13), Abu Gharadig Oil Field, North Western Desert, Egypt. Some of the marine (dinoflagellate cysts), as well as the terrestrial palynoflora (spores and pollen grains), reveal extinction and origination patterns that are known elsewhere, although other species may be survived across the Cenomanian-Turonian boundary. This implies control of global changes on the palynoflora, i.e., impact of Oceanic Anoxic Event OAE2 (Bonarelli Event), rather than changes in the local environmental conditions. The basal part of the Abu Roach Formation ('G' and 'F' members, late Cenomanian) shows a positive δ ¹³C excursion of the organic fraction. The TOC is generally high between 2.20 and 3.04 % in the basal Abu Roash Formation: shale of 'G' and carbonate of 'F' members, which indicates that these two members are the main Cretaceous source rocks in the Abu Gharadig Basin and have a type I-II kerogen composition. They are distinguished by an abundance of amorphous organic matter AOM and Chlorococcalean algae, mainly Pediastrum and Scenedesmus, along with subordinate dinoflagellate cysts.

Keywords: oceanic anoxic event, cenomanian-turonian, palynofacies, western desert, Egypt

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544 Effect of Depth on the Distribution of Zooplankton in Wushishi Lake Minna, Niger State, Nigeria

Authors: Adamu Zubairu Mohammed, Fransis Oforum Arimoro, Salihu Maikudi Ibrahim, Y. I. Auta, T. I. Arowosegbe, Y. Abdullahi

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The present study was conducted to evaluate the effect of depth on the distribution of zooplankton and some physicochemical parameters in Tungan Kawo Lake (Wushishi dam). Water and zooplankton samples were collected from the surface, 3.0 meters deep and 6.0 meters deep, for a period of 24 hours for six months. Standard procedures were adopted for the determination of physicochemical parameters. Results have shown significant differences in the pH, DO, BOD Hardness, Na, and Mg. A total of 1764 zooplankton were recorded, comprising 35 species, with cladocera having 18 species (58%), 14 species of copepoda (41%), 3 species of diptera (1.0%). Results show that more of the zooplankton were recorded in the 3.0 meters-deep region compared to the two other depts and a significant difference was observed in the distribution of Ceriodaphnia dubia, Daphnia laevis, and Leptodiaptomus coloradensis. Though the most abundant zooplankton was recorded in the 3.0 meters deep, Leptodiaptomus coloradesnsis, which was observed in the 6.0 meters deep as the most individual observed, this was followed by Daphnia laevis. Canonical correspondence analysis between physicochemical parameters and the zooplankton indicated a good relationship in the Lake. Ceriodaphnia dubia was found to have a good association with oxygen, sodium, and potassium, while Daphnia laevis and Leptodiaptomus coloradensis are in good relationship with magnesium and phosphorus. It was generally observed that this depth does not have much influence on the distribution of zooplankton in Wushishi Lake.

Keywords: zooplankton, standard procedures, canonical correspondence analysis, Wushishi, canonical, physicochemical parameter

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543 A Review of the Factors That Influence on Nutrient Removal in Upflow Filters

Authors: Ali Alzeyadi, Edward Loffill, Rafid Alkhaddar Ali Alattabi

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Phosphate, ammonium, and nitrates are forms of nutrients; they are released from different sources. High nutrient levels contribute to the eutrophication of water bodies by accelerating the extraordinary growth of algae. Recently, many filtration and treatment systems were developed and used for different removal processes. Due to enhanced operational aspects for the up-flow, continuous, granular Media filter researchers became more interested in further developing this technology and its performance for nutrient removal from wastewater. Environmental factors significantly affect the filtration process performance, and understanding their impact will help to maintain the nutrient removal process. Phosphate removal by phosphate sorption materials PSMs and nitrogen removal biologically are the methods of nutrient removal that have been discussed in this paper. Hence, the focus on the factors that influence these processes is the scope of this work. The finding showed the presence of factors affecting both removal processes; the size, shape, and roughness of the filter media particles play a crucial role in supporting biofilm formation. On the other hand, all of which are effected on the reactivity of surface between the media and phosphate. Many studies alluded to factors that have significant influence on the biological removal for nitrogen such as dissolved oxygen, temperature, and pH; this is due to the sensitivity of biological processes while the phosphate removal by PSMs showed less affected by these factors. This review work provides help to the researchers in create a comprehensive approach in regards study the nutrient removal in up flow filtration systems.

Keywords: nitrogen biological treatment, nutrients, psms, upflow filter, wastewater treatment

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542 Comparative Study Using WEKA for Red Blood Cells Classification

Authors: Jameela Ali, Hamid A. Jalab, Loay E. George, Abdul Rahim Ahmad, Azizah Suliman, Karim Al-Jashamy

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Red blood cells (RBC) are the most common types of blood cells and are the most intensively studied in cell biology. The lack of RBCs is a condition in which the amount of hemoglobin level is lower than normal and is referred to as “anemia”. Abnormalities in RBCs will affect the exchange of oxygen. This paper presents a comparative study for various techniques for classifying the RBCs as normal, or abnormal (anemic) using WEKA. WEKA is an open source consists of different machine learning algorithms for data mining applications. The algorithm tested are Radial Basis Function neural network, Support vector machine, and K-Nearest Neighbors algorithm. Two sets of combined features were utilized for classification of blood cells images. The first set, exclusively consist of geometrical features, was used to identify whether the tested blood cell has a spherical shape or non-spherical cells. While the second set, consist mainly of textural features was used to recognize the types of the spherical cells. We have provided an evaluation based on applying these classification methods to our RBCs image dataset which were obtained from Serdang Hospital-alaysia, and measuring the accuracy of test results. The best achieved classification rates are 97%, 98%, and 79% for Support vector machines, Radial Basis Function neural network, and K-Nearest Neighbors algorithm respectively.

Keywords: K-nearest neighbors algorithm, radial basis function neural network, red blood cells, support vector machine

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541 Method of Estimating Absolute Entropy of Municipal Solid Waste

Authors: Francis Chinweuba Eboh, Peter Ahlström, Tobias Richards

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Entropy, as an outcome of the second law of thermodynamics, measures the level of irreversibility associated with any process. The identification and reduction of irreversibility in the energy conversion process helps to improve the efficiency of the system. The entropy of pure substances known as absolute entropy is determined at an absolute reference point and is useful in the thermodynamic analysis of chemical reactions; however, municipal solid waste (MSW) is a structurally complicated material with unknown absolute entropy. In this work, an empirical model to calculate the absolute entropy of MSW based on the content of carbon, hydrogen, oxygen, nitrogen, sulphur, and chlorine on a dry ash free basis (daf) is presented. The proposed model was derived from 117 relevant organic substances which represent the main constituents in MSW with known standard entropies using statistical analysis. The substances were divided into different waste fractions; namely, food, wood/paper, textiles/rubber and plastics waste and the standard entropies of each waste fraction and for the complete mixture were calculated. The correlation of the standard entropy of the complete waste mixture derived was found to be somsw= 0.0101C + 0.0630H + 0.0106O + 0.0108N + 0.0155S + 0.0084Cl (kJ.K-1.kg) and the present correlation can be used for estimating the absolute entropy of MSW by using the elemental compositions of the fuel within the range of 10.3%  C 95.1%, 0.0%  H  14.3%, 0.0%  O  71.1%, 0.0  N  66.7%, 0.0%  S  42.1%, 0.0%  Cl  89.7%. The model is also applicable for the efficient modelling of a combustion system in a waste-to-energy plant.

Keywords: absolute entropy, irreversibility, municipal solid waste, waste-to-energy

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540 Bioremediation of Paper Mill Effluent by Microbial Consortium Comprising Bacterial and Fungal Strain and Optimizing the Effect of Carbon Source

Authors: Priya Tomar, Pallavi Mittal

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Bioremediation has been recognized as an environment friendly and less expensive method which involves the natural processes resulting in the efficient conversion of hazardous compounds into innocuous products. The pulp and paper mill effluent is one of the high polluting effluents amongst the effluents obtained from polluting industries. The colouring body present in the wastewater from pulp and paper mill is organic in nature and is comprised of wood extractives, tannin, resins, synthetic dyes, lignin, and its degradation products formed by the action of chlorine on lignin which imparts an offensive colour to the water. These mills use different chemical process for paper manufacturing due to which lignified chemicals are released into the environment. Therefore, the chemical oxygen demand (COD) of the emanating stream is quite high. For solving the above problem we present this paper with some new techniques that were developed for the efficiency of paper mill effluents. In the present study we utilized the consortia of fungal and bacterial strain and the treatment named as C1, C2, and C3 for the decolourization of paper mill effluent. During the study, role of carbon source i.e. glucose was studied for decolourization. From the results it was observed that a maximum colour reduction of 66.9%, COD reduction of 51.8%, TSS reduction of 0.34%, TDS reduction of 0.29% and pH changes of 4.2 is achieved by consortia of Aspergillus niger with Pseudomonas aeruginosa. Data indicated that consortia of Aspergillus niger with Pseudomonas aeruginosa is giving better result with glucose.

Keywords: bioremediation, decolourization, black liquor, mycoremediation

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539 Anethum graveolens Prevents Liver and Kidney Injury, Oxidative Stress and Inflammation in Mice Exposed to Nicotine Perinatally

Authors: Saleh N. Maodaa

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Perinatal exposure to nicotine imbalances the redox status in newborns. This study investigated the effect of Anethum graveolens (dill) extract on oxidative stress and tissue injury in the liver and kidney of mice newborns exposed to nicotine perinatally. Pregnant mice received nicotine (0.25 mg/kg) on gestational day 12 to day 5 after birth and/or A. graveolens extract on a gestational day 1 to day 15 after birth. Newborn mice exposed to nicotine showed multiple histopathological alterations in the kidney and liver, including inflammatory cell infiltration and degenerative changes. Nicotine exposure increased hepatic and renal reactive oxygen species (ROS), lipid peroxidation, tumor necrosis factor (TNF-_), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) (p < 0.001), and decreased antioxidant defenses (p < 0.001). A. graveolens supplementation significantly prevented liver and kidney injury, suppressed ROS generation (p < 0.001), lipid peroxidation (p < 0.001), and inflammatory response (p < 0.001), and enhanced antioxidant defenses. In addition, A. graveolens upregulated hepatic and renal Nrf2 and HO-1 mRNA and increased HO-1 activity in normal and nicotine-exposed mice. In conclusion, A. graveolens protects against perinatal nicotine-induced oxidative stress, inflammation, and tissue injury in the liver and kidney of newborn mice. A. graveolens upregulated hepatic and renal Nrf2/HO-1 signaling and enhanced antioxidant defenses in mice.

Keywords: dill, oxidative stress, cytokines, nicotine

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538 Synthesis of New Bio-Based Solid Polymer Electrolyte Polyurethane-Liclo4 via Prepolymerization Method: Effect of NCO/OH Ratio on Their Chemical, Thermal Properties and Ionic Conductivity

Authors: C. S. Wong, K. H. Badri, N. Ataollahi, K. P. Law, M. S. Su’ait, N. I. Hassan

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Novel bio-based polymer electrolyte was synthesized with LiClO4 as the main source of charge carrier. Initially, polyurethane-LiClO4 polymer electrolytes were synthesized via polymerization method with different NCO/OH ratios and labelled as PU1, PU2, PU3, and PU4. Subsequently, the chemical, thermal properties and ionic conductivity of the films produced were determined. Fourier transform infrared (FTIR) analysis indicates the co-ordination between Li+ ion and polyurethane in PU1 due to the greatest amount of hard segment of polyurethane in PU1 as proven by soxhlet analysis. The structures of polyurethanes were confirmed by 13 nuclear magnetic resonance spectroscopy (13C NMR) and FTIR spectroscopy. Differential scanning calorimetry (DSC) analysis indicates PU 1 has the highest glass transition temperature (Tg) corresponds to the most abundant urethane group which is the hard segment in PU1. Scanning electron microscopy (SEM) of the PU-LiClO4 shows the good miscibility between lithium salt and the polymer. The study found that PU1 possessed the greatest ionic conductivity (1.19 × 10-7 S.cm-1 at 298 K and 5.01 × 10-5 S.cm-1 at 373 K) and the lowest activation energy, Ea (0.32 eV) due to the greatest amount of hard segment formed in PU 1 induces the coordination between lithium ion and oxygen atom of carbonyl group in polyurethane. All the polyurethanes exhibited linear Arrhenius variations indicating ion transport via simple lithium ion hopping in polyurethane. This research proves the NCO content in polyurethane plays an important role in affecting the ionic conductivity of this polymer electrolyte.

Keywords: ionic conductivity, palm kernel oil-based monoester-OH, polyurethane, solid polymer electrolyte

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537 Observations on the Eastern Red Sea Elasmobranchs: Data on Their Distribution and Ecology

Authors: Frappi Sofia, Nicolas Pilcher, Sander DenHaring, Royale Hardenstine, Luis Silva, Collin Williams, Mattie Rodrigue, Vincent Pieriborne, Mohammed Qurban, Carlos M. Duarte

Abstract:

Nowadays, elasmobranch populations are disappearing at a dangerous rate, mainly due to overexploitation, extensive fisheries, as well as climate change. The decline of these species can trigger a cascade effect, which may eventually lead to detrimental impacts on local ecosystems. The Elasmobranch in the Red Sea is facing one of the highest risks of extinction, mainly due to unregulated fisheries activities. Thus, it is of paramount importance to assess their current distribution and unveil their environmental preferences in order to improve conservation measures. Important data have been collected throughout the whole red Sea during the Red Sea Decade Expedition (RSDE) to achieve this goal. Elasmobranch sightings were gathered through the use of submarines, remotely operated underwater vehicles (ROV), scuba diving operations, and helicopter surveys. Over a period of 5 months, we collected 891 sightings, 52 with submarines, 138 with the ROV, 67 with the scuba diving teams, and 634 from helicopters. In total, we observed 657 and 234 individuals from the superorder Batoidea and Selachimorpha, respectively. The most common shark encountered was Iago omanensis, a deep-water shark of the order Carcharhiniformes. To each sighting, data on temperature, salinity density, and dissolved oxygen were integrated to reveal favorable conditions for each species. Additionally, an extensive literature review on elasmobranch research in the Eastern Red Sea has been carried out in order to obtain more data on local populations and to be able to highlight patterns of their distribution.

Keywords: distribution, elasmobranchs, habitat, rays, red sea, sharks

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536 Impact of Edible Coatings Made of Chitosan and Spray Dried Propolis in the Shell Life of White Cachama (Piaractus brachypomus)

Authors: David Guillermo Piedrahita Marquez, Hector Suarez Mahecha, Jairo Humberto Lopez

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There is a need to preserve aquaculture matrices due to their high nutritional value, and its broad consumption, one of those species is the white cachama (Piaractus brachypomus), this fish is located in the rivers of eastern Colombia, and the previously mentioned species needs more study. Therefore, in a paper the effects of an alternative method of preservation of shell life were investigated, the method used is the application of an edible coating made from chitosan and ethanolic extract of propolis (EEP) encapsulated in maltodextrin. The coating was applied by immersion, and after that, we investigated the post mortem quality changes of the fish performing physicochemical and microbiological analysis. pH, volatile bases, test thiobarbituric acid and peroxide value were tested; finally, we studied the effect of the coating on mesophilic strains, coliforms and other microorganisms such as Staphylococcus, and Salmonella. Finally, we concluded that the coating prolongs the shelf life because it acts as a barrier to oxygen and moisture, the bioactive compounds trap free radicals and the coatings changes the metabolism and cause the cell lysis of the microorganisms. It was determined that the concentration of malonaldehyde, the volatile basic nitrogen content and pH are the variables that distinguish more clearly between the samples with the treatment and the control samples.

Keywords: antimicrobial activity, lipid oxidation, texture profile analysis (TPA), sensorial analysis, peroxide value, thiobarbituric acid assay (TBA), total volatile basic nitrogen (TVB-N)

Procedia PDF Downloads 276
535 A Study on the Treatment of Municipal Waste Water Using Sequencing Batch Reactor

Authors: Bhaven N. Tandel, Athira Rajeev

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Sequencing batch reactor process is a suspended growth process operating under non-steady state conditions which utilizes a fill and draw reactor with complete mixing during the batch reaction step (after filling) and where the subsequent steps of aeration and clarification occur in the same tank. All sequencing batch reactor systems have five steps in common, which are carried out in sequence as follows, (1) fill (2) react (3) settle (sedimentation/clarification) (4) draw (decant) and (5) idle. The study was carried out in a sequencing batch reactor of dimensions 44cmx30cmx70cm with a working volume of 40 L. Mechanical stirrer of 100 rpm was used to provide continuous mixing in the react period and oxygen was supplied by fish tank aerators. The duration of a complete cycle of sequencing batch reactor was 8 hours. The cycle period was divided into different phases in sequence as follows-0.25 hours fill phase, 6 hours react period, 1 hour settling phase, 0.5 hours decant period and 0.25 hours idle phase. The study consisted of two runs, run 1 and run 2. Run 1 consisted of 6 hours aerobic react period and run 2 consisted of 3 hours aerobic react period followed by 3 hours anoxic react period. The influent wastewater used for the study had COD, BOD, NH3-N and TKN concentrations of 308.03±48.94 mg/L, 100.36±22.05 mg/L, 14.12±1.18 mg/L, and 24.72±2.21 mg/L respectively. Run 1 had an average COD removal efficiency of 41.28%, BOD removal efficiency of 56.25%, NH3-N removal efficiency of 86.19% and TKN removal efficiency of 54.4%. Run 2 had an average COD removal efficiency of 63.19%, BOD removal efficiency of 73.85%, NH3-N removal efficiency of 90.74% and TKN removal efficiency of 65.25%. It was observed that run 2 gave better performance than run 1 in the removal of COD, BOD and TKN.

Keywords: municipal waste water, aerobic, anoxic, sequencing batch reactor

Procedia PDF Downloads 527
534 The Association between Obstructive Sleep Apnea Syndrome and Driver Fatigue in North Taiwan Urban Areas

Authors: Cheng-Yu Tsai, Wen-Te Liu, Chen-Chen Lo, Yin-Tzu Lin, Kang Lo

Abstract:

Background: Driving fatigue related to inadequate or disordered sleep accounts for a major percentage of traffic accidents. Obstructive sleep apnea syndrome (OSAS) is a common respiratory disorder during sleep. However, the effects of OSAS severity on driving drowsiness remain unclear. Objective: The aim of this study is to investigate the relationship between OSAS severity and driving fatigue. Methodologies: The physical condition while driving was obtained from the questionnaires to classify the state of driving fatigue. OSAS severity was quantified as the polysomnography, and the mean hourly number of greater than 3% dips in oxygen saturation during examination in a hospital in New Taipei City (Taiwan). The severity of OSAS was diagnosed by the apnea and hypopnea index (AHI) with the American Academy of Sleep Medicine (AASM) guideline. The logistic regression model was used to examine the associations after adjusted age, gender, neck circumstance, waist circumstance, and body mass index (BMI). Results: There were 880 subjects recruited in this study, who had been done polysomnography for evaluating severity for OSAS as well as completed the driver condition questionnaire. 752 subjects were diagnosed with OSA, and 484 subjects had fatigue driving behavior in the past week. Patients diagnosed with OSAS had a 9.42-fold higher odds ratio (p < 0.01, 95% CI = 5.41 – 16.42) of driving drowsiness for cohorts with a normal degree. Conclusion: We observe the considerable correlation between OSAS and driving fatigue. For the purpose of promoting traffic safety, OSAS should be monitored and treated.

Keywords: obstructive sleep apnea syndrome, driving fatigue, polysomnography, apnea and hypopnea index

Procedia PDF Downloads 114
533 Joint Replenishment and Heterogeneous Vehicle Routing Problem with Cyclical Schedule

Authors: Ming-Jong Yao, Chin-Sum Shui, Chih-Han Wang

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This paper is developed based on a real-world decision scenario that an industrial gas company that applies the Vendor Managed Inventory model and supplies liquid oxygen with a self-operated heterogeneous vehicle fleet to hospitals in nearby cities. We name it as a Joint Replenishment and Heterogeneous Vehicle Routing Problem with Cyclical Schedule and formulate it as a non-linear mixed-integer linear programming problem which simultaneously determines the length of the planning cycle (PC), the length of the replenishment cycle and the dates of replenishment for each customer and the vehicle routes of each day within PC, such that the average daily operation cost within PC, including inventory holding cost, setup cost, transportation cost, and overtime labor cost, is minimized. A solution method based on genetic algorithm, embedded with an encoding and decoding mechanism and local search operators, is then proposed, and the hash function is adopted to avoid repetitive fitness evaluation for identical solutions. Numerical experiments demonstrate that the proposed solution method can effectively solve the problem under different lengths of PC and number of customers. The method is also shown to be effective in determining whether the company should expand the storage capacity of a customer whose demand increases. Sensitivity analysis of the vehicle fleet composition shows that deploying a mixed fleet can reduce the daily operating cost.

Keywords: cyclic inventory routing problem, joint replenishment, heterogeneous vehicle, genetic algorithm

Procedia PDF Downloads 62
532 High Temperature Oxidation of Additively Manufactured Silicon Carbide/Carbon Fiber Nanocomposites

Authors: Saja M. Nabat Al-Ajrash, Charles Browning, Rose Eckerle, Li Cao, Robyn L. Bradford, Donald Klosterman

Abstract:

An additive manufacturing process and subsequent pyrolysis cycle were used to fabricate SiC matrix/carbon fiber hybrid composites. The matrix was fabricated using a mixture of preceramic polymer and acrylate monomers, while polyacrylonitrile (PAN) precursor was used to fabricate fibers via electrospinning. The precursor matrix and reinforcing fibers at 0, 2, 5, or 10 wt% were printed using digital light processing, and both were simultaneously pyrolyzed to yield the final ceramic matrix composite structure. After pyrolysis, XRD and SEAD analysis proved the existence of SiC nanocrystals and turbostratic carbon structure in the matrix, while the reinforcement phase was shown to have a turbostratic carbon structure similar to commercial carbon fibers. Thermogravimetric analysis (TGA) in the air up to 1400 °C was used to evaluate the oxidation resistance of this material. TGA results showed some weight loss due to oxidation of SiC and/or carbon up to about 900 °C, followed by weight gain to about 1200 °C due to the formation of a protective SiO2 layer. Although increasing carbon fiber content negatively impacted the total mass loss for the first heating cycle, exposure of the composite to second-run air revealed negligible weight chance. This is explained by SiO2 layer formation, which acts as a protective film that prevents oxygen diffusion. Oxidation of SiC and the formation of a glassy layer has been proven to protect the sample from further oxidation, as well as provide healing of surface cracks and defects, as revealed by SEM analysis.

Keywords: silicon carbide, carbon fibers, additive manufacturing, composite

Procedia PDF Downloads 57
531 Studies on the Spontaneous Reductive Decomposition Behavior of Permanganate in the Water

Authors: Hyun Kyu Lee, Won Zin Oh, June Hyun Kim, Jin Hee Kim, Sang June Choi, Hak Soo Kim

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The oxidative dissolution of chromium oxide by manganese oxides including permanganate have been widely studied not only for the chemical decontamination of nuclear power plant, but also for the environmental control of the toxic chromate caused by naturally occurring manganese dioxide. However, little attention has been made for the spontaneous reductive decomposition of permanganate in the water, which is a competing reaction with the oxidation of the chromium oxide by permanganate. The objective of this study is to investigate the spontaneous reductive decomposition behavior of permanganate in the water, depending on the variation of acidity, temperature and concentration. Results of the experiments showed that the permanganate reductive decomposition product is manganese dioxide, and this reaction accompanies with the same molar amount of hydrogen ion consumption. Therefore, at the neutral condition (ex. potassium permanganate solution without acidic chemicals), the permanganate do not reduce by itself at any condition of temperature, concentration within the experimental range. From the results, we confirmed that the oxidation reaction for the permanganate reduction is the water oxidation that is accompanying the oxygen evolution. The experimental results on the reductive decomposition behavior of permanganate in the water also showed that the degree and rate of permanganate reduction increases with the temperature, acidity and concentration. The spontaneous decomposition of the permanganates obtained in the studies would become a good reference to select the operational condition, such as temperature, acidity and concentration, for the chemical decontamination of nuclear power plants.

Keywords: permanganate reduction, spontaneous decomposition, water oxidation, acidity, temperature, permanganate concentration, chemical decontamination, nuclear power plant

Procedia PDF Downloads 330
530 Ecological Studies on Bulinus truncatus Snail the Intermediate Host of Schistosoma haematobium, in White Nile State, Sudan

Authors: Mohammed Hussein Eltoum Salih

Abstract:

This study was conducted in four villages, namely: Jadeed, Alandraba, Um Gaar, and EL Shetabe in the White Nile State Sudan, to determine the ecological factors; water vegetations, physical and chemical properties of the water in Snails habitat. Bulinus truncatus, which act as an intermediate host for S. haematobium, were collected from water bodies adjacent to study villages where the residents were suspected to swim, and humans get in contact with water for various purposes. Water samples from the stretches were collected and then measured for parameters that are indicative of the quality of water and sustaining the survival of snails and would confirm even further if the contact between humans and water had taken place. The parameters measured included water conductivity, pH, dissolved oxygen, calcium, and magnesium content. Also, a single water sample from each contact site was collected for microbiological tests. The result revealed that the B. truncatus showed that these animals were fewer and free of infection and their sites of the collection were dense with different plant species making them suitable to harbor snails. Moreover, the results of microbial tests showed that there was higher bacterial contamination. Also, physical and chemical analysis of water sample of contact sites revealed that there were significant differences (p < 0.05) in water pH, calcium, and magnesium content between sites of study villages, and these were discussed in relation to factors suitable for the intermediate hosts and thus for the transmission of the S. haematobium disease.

Keywords: health, parasitology, Schistosoma, snails

Procedia PDF Downloads 137
529 Evaluation of Liquid Fermentation Strategies to Obtain a Biofertilizer Based on Rhizobium sp.

Authors: Andres Diaz Garcia, Ana Maria Ceballos Rojas, Duvan Albeiro Millan Montano

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This paper describes the initial technological development stages in the area of liquid fermentation required to reach the quantities of biomass of the biofertilizer microorganism Rhizobium sp. strain B02, for the application of the unitary stages downstream at laboratory scale. In the first stage, the adjustment and standardization of the fermentation process in conventional batch mode were carried out. In the second stage, various fed-batch and continuous fermentation strategies were evaluated in 10L-bioreactor in order to optimize the yields in concentration (Colony Forming Units/ml•h) and biomass (g/l•h), to make feasible the application of unit operations downstream of process. The growth kinetics, the evolution of dissolved oxygen and the pH profile generated in each of the strategies were monitored and used to make sequential adjustments. Once the fermentation was finished, the final concentration and viability of the obtained biomass were determined and performance parameters were calculated with the purpose of select the optimal operating conditions that significantly improved the baseline results. Under the conditions adjusted and standardized in batch mode, concentrations of 6.67E9 CFU/ml were reached after 27 hours of fermentation and a subsequent noticeable decrease was observed associated with a basification of the culture medium. By applying fed-batch and continuous strategies, significant increases in yields were achieved, but with similar concentration levels, which involved the design of several production scenarios based on the availability of equipment usage time and volume of required batch.

Keywords: biofertilizer, liquid fermentation, Rhizobium sp., standardization of processes

Procedia PDF Downloads 161
528 Aerobic Capacity Outcomes after an Aerobic Exercise Program with an Upper Body Ergometer in Diabetic Amputees

Authors: Cecilia Estela Jiménez Pérez Campos

Abstract:

Introduction: Amputation comes from a series of complications in diabetic persons; at that point, of the illness evolution they have a deplored aerobic capacity. Adding to that, cardiac rehabs programs are almost base in several activities in a standing position. The cardiac rehabilitation programs have to improve for them, based on scientific advice. Objective: Evaluation of aerobic capacity of diabetic amputee after an aerobic exercise program, with upper limb ergometer. Methodology: The design is longitudinal, prospective, comparative and no randomized. We include all diabetic pelvic limb amputees, who assist to the cardiac rehabilitation. We made 2 groups: an experimental and a control group. The patients did the exercise testing, with the author’s design protocol. The experimental group completed 24 exercise sessions (3 sessions/week), with an intensity determined with the training heart rate. At the end of 8 weeks period, the subjects did a second exercise test. Results: Both groups were a homogeneous sample in age (experimental n=15) 57.6+12.5 years old and (control n=8) 52.5+8.0 years old, sex, occupation, education and economic features. (square chi) (p=0.28). The initial aerobic capacity was similar in both groups. And the aerobic capacity accomplishes after the program was statistically greater in the experimental group than in the control one. The final media VO2peak (mlO2/kg/min) was experimental (17.1+3.8), control (10.5+3.8), p=0.001. (t student). Conclusions: The aerobic capacity improved after an arm ergometer exercise program and the quality of life improve too, in diabetic amputees. So this program is fundamental in diabetic amputee’s rehabilitation management.

Keywords: aerobic fitness, metabolic equivalent (MET), oxygen output, upper limb ergometer

Procedia PDF Downloads 217
527 Molecular Dynamics Studies of Main Factors Affecting Mass Transport Phenomena on Cathode of Polymer Electrolyte Membrane Fuel Cell

Authors: Jingjing Huang, Nengwei Li, Guanghua Wei, Jiabin You, Chao Wang, Junliang Zhang

Abstract:

In this work, molecular dynamics (MD) simulation is applied to analyze the mass transport process in the cathode of proton exchange membrane fuel cell (PEMFC), of which all types of molecules situated in the cathode is considered. a reasonable and effective MD simulation process is provided, and models were built and compared using both Materials Studio and LAMMPS. The mass transport is one of the key issues in the study of proton exchange membrane fuel cells (PEMFCs). In this report, molecular dynamics (MD) simulation is applied to analyze the influence of Nafion ionomer distribution and Pt nano-particle size on mass transport process in the cathode. It is indicated by the diffusion coefficients calculation that a larger quantity of Nafion, as well as a higher equivalent weight (EW) value, will hinder the transport of oxygen. In addition, medium-sized Pt nano-particles (1.5~2nm) are more advantageous in terms of proton transport compared with other particle sizes (0.94~2.55nm) when the center-to-center distance between two Pt nano-particles is around 5 nm. Then mass transport channels are found to be formed between the hydrophobic backbone and the hydrophilic side chains of Nafion ionomer according to the radial distribution function (RDF) curves. And the morphology of these channels affected by the Pt size is believed to influence the transport of hydronium ions and, consequently the performance of PEMFC.

Keywords: cathode catalytic layer, mass transport, molecular dynamics, proton exchange membrane fuel cell

Procedia PDF Downloads 200