scholarly journals Fullers Earth Treatment for Esters Liquids used in Power Apparatuses: Inferences and Arguments

2021 ◽  
Vol 1 (1) ◽  
pp. 38-42
Author(s):  
Issouf Fofana ◽  
Yohan Bergeron ◽  
Marie-Pier Gagnon ◽  
Jonathan Tremblay ◽  
Luc Loiselle ◽  
...  
Keyword(s):  
Treatment Temperature ◽  
Uv Spectrophotometry ◽  
Liquid Ratio ◽  
Experimental Conditions ◽  
High Importance ◽  
Dielectric Fluids ◽  
Insulating Liquids ◽  
Controlled Treatment ◽  
Before And After ◽  
Fuller’S Earth

Insulating Liquids are widely used for their electrical and thermal properties in power apparatuses, particularly at the level of liquid-filled transformers. With the shift in engineering aspects towards sustainable development, it is important to find a sustainable solution with ecofriendly nature. Therefore, alternative (biodegradable) liquids are of high importance in the global transformer communities. In the present study, the alternative dielectric fluids (ester-based) feasibility for potential regeneration with Fuller’s earth is investigated. The experimental results are confined to the reclamation temperature as well as the ratio of Fuller's earth (the sorbent) and the liquid. A suitable laboratory treatment apparatus is designed and is adopted in this study. Promising measurements to comment on the effectiveness of the treatment have been performed at controlled treatment temperature and sorbent-liquid ratio with the ASTM 7150-13 as a reference norm.The results of this study allowed 80°C and 1 g/30 ml as affirmative conditions for the present experimental conditions. Diagnostic measurements include turbidity, particle counter, and UV spectrophotometry before and after treatments. It is inferred that fuller’s earth is not a promising sorbent for the reclamation of ester liquids.

Study of Modified Dry Desulfurization Ash in a Power Plant for Sequestering CO2 from a Micron-Nanoscale Perspective

2021 ◽  
Vol 21 (1) ◽  
pp. 382-391
Author(s):  
Jieying Cai ◽  
Xiangdong Li ◽  
Di Chen ◽  
Qiyan Feng
Keyword(s):  
Carbon Sequestration ◽  
Initial Pressure ◽  
Kinetics Equation ◽  
Liquid Ratio ◽  
Experimental Conditions ◽  
X Ray ◽  
First Order ◽  
First Order Kinetics ◽  
Before And After ◽  
Solid Liquid

To improve the CO2 fixation ability of dry desulfurization ash (DDA), a DDA must be modified by chemical methods. At the micron level, the changes in microstructure and chemical composition before and after DDA modification were analysed by Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscopy (EDS), and the reaction mechanism of the modification process was inferred. On the other hand, the chemical and mineral phase compositions of the modified DDA and its solid products were analysed by X ray Fluorescence (XRF) and X-ray diffraction (XRD). In addition, the microstructure of the modified DDA before and after sequestration at nanometre resolution was studied by SEM-EDS so that the curing mechanism of the modified DDA was clearly defined. Then, the effects of the solid–liquid ratio, temperature, pressure and reaction time on the sequestration of CO2 in the modified DDA were studied with aqueous carbonation. The results showed that the higher the temperature is, the higher the solid–liquid ratio, and the lower initial pressure is, the less the CO2 sequestered in the modified DDA and the less the carbon sequestration capacity of the modified DDA. Under the experimental conditions, the carbonation efficiency of the modified DDA could reach 94.42%, and 1 ton of modified DDA could sequester up to 50.61 kg CO2. Compared with conventional DDA, the carbon sequestration capacity is effectively improved. The kinetic data confirmed that the fitting correlation of the quasi-first-order kinetics equation is more significant. The smaller the solid–liquid ratio is, the lower the temperature, the higher the initial pressure, and the higher the rate constant of the quasi-first-order kinetics equation.

scholarly journals Adsorption Studies on Magnetic Nanoparticles Functionalized with Silver to Remove Nitrates from Waters

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1757
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca ◽  
Miguel Ángel Martín-Pereira ◽  
María del Carmen García-Onsurbe
Keyword(s):  
Magnetic Nanoparticles ◽  
Nitrate Content ◽  
Adsorption Efficiency ◽  
Experimental Conditions ◽  
Dependent Behavior ◽  
Before And After ◽  
Naoh Solution ◽  
High Concentrations ◽  
Interference Studies

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.

scholarly journals Experimental Study on the Water Selective Dense Membrane under an Absolute Pressure Difference with Simplified Test Method

2021 ◽  
Vol 11 (4) ◽  
pp. 1710
Author(s):  
Jinwook Lee ◽  
Hyo-Sun Kim ◽  
Donik Ku ◽  
Jihun Lim ◽  
Minkyu Jung ◽  
...  
Keyword(s):  
Measurement Methods ◽  
Test Method ◽  
Coefficient Of Performance ◽  
Absolute Pressure ◽  
Air Conditioner ◽  
Experimental Conditions ◽  
Simple Method ◽  
Performance Factors ◽  
Dense Membrane ◽  
Before And After

Membrane-based vacuum dehumidification technology is currently being actively studied. In most studies, the performance of the membrane-based systems is evaluated under the assumption that the membrane can achieve ideal separation, which results in ideal coefficient of performance (COP) values. However, the performance factors for membranes vary depending on the experimental conditions and measurement methods. Therefore, relevant values can only be calculated if the data are measured in an environment close to that of the application conditions. The cup measurement method is a simple method to measure the permeability, however, there are limitations regarding adding variables during the experiment. To overcome these limitations, a new experimental device was constructed that combines pressurized cell with the cup method. Using the device, the performance of polyethylene-amide-bonded dense membranes was evaluated under conditions where absolute pressure differentials occurred before and after the membrane, such as in air conditioner dehumidification systems.

scholarly journals Enzymatic Process for Cystoseira barbata Valorization: Ethanol Production and Additional By-Products

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 741
Author(s):  
Doinita-Roxana Cioroiu Tirpan ◽  
Ancaelena Eliza Sterpu ◽  
Claudia Irina Koncsag ◽  
Alina Georgiana Ciufu ◽  
Tănase Dobre
Keyword(s):  
Ethanol Production ◽  
Alcoholic Fermentation ◽  
Ethanol Yield ◽  
Product Yield ◽  
Liquid Ratio ◽  
Experimental Conditions ◽  
Factors Affecting ◽  
Cystoseira Barbata ◽  
Main Factors ◽  
Process Factors

The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against diseases and physical disorders.

Caffeine counteracts the ergogenic action of muscle creatine loading

1996 ◽  
Vol 80 (2) ◽  
pp. 452-457 ◽  
Author(s):  
K. Vandenberghe ◽  
N. Gillis ◽  
M. Van Leemputte ◽  
P. Van Hecke ◽  
F. Vanstapel ◽  
...  
Keyword(s):  
Intermittent Exercise ◽  
Creatine Supplementation ◽  
Knee Extensors ◽  
Caffeine Intake ◽  
Resonance Spectroscopy ◽  
Experimental Conditions ◽  
Before And After ◽  
And Performance ◽  
Exercise Fatigue ◽  
Voluntary Contractions

This study aimed to compare the effects of oral creatine (Cr) supplementation with creatine supplementation in combination with caffeine (Cr+C) on muscle phosphocreatine (PCr) level and performance in healthy male volunteers (n = 9). Before and after 6 days of placebo, Cr (0.5 g x kg-1 x day-1), or Cr (0.5 g x kg-1 x day-1) + C (5 mg x kg-1 x day-1) supplementation, 31P-nuclear magnetic resonance spectroscopy of the gastrocnemius muscle and a maximal intermittent exercise fatigue test of the knee extensors on an isokinetic dynamometer were performed. The exercise consisted of three consecutive maximal isometric contractions and three interval series of 90, 80, and 50 maximal voluntary contractions performed with a rest interval of 2 min between the series. Muscle ATP concentration remained constant over the three experimental conditions. Cr and Cr+C increased (P < 0.05) muscle PCr concentration by 4-6%. Dynamic torque production, however, was increased by 10-23% (P < 0.05) by Cr but was not changed by Cr+C. Torque improvement during Cr was most prominent immediately after the 2-min rest between the exercise bouts. The data show that Cr supplementation elevates muscle PCr concentration and markedly improves performance during intense intermittent exercise. This ergogenic effect, however, is completely eliminated by caffeine intake.

scholarly journals Running velocity at the ventilatory threshold and at VO2max, before and after the eight-week cardiovascular endurance training

2005 ◽  
Vol 58 (1-2) ◽  
pp. 27-31
Author(s):  
Stanimir Stojiljkovic ◽  
Sanja Mazic ◽  
Dejan Nesic ◽  
Sasko Velkovski ◽  
Dusan Mitrovic
Keyword(s):  
Endurance Training ◽  
Ventilatory Threshold ◽  
Exercise Program ◽  
Test Results ◽  
Final Test ◽  
Experimental Conditions ◽  
Cardiovascular Endurance ◽  
Before And After ◽  
Test Velocity ◽  
Male Subjects

Introduction The purpose of this research was to compare changes in running velocity at ventilatory threshold with the veliocity at VO2max, before and after the eight-week exercise program. Material and methods 32 male subjects (age: 22.3? 2.5 years, height: 179.8? 7.6 cm, body mass: 76.8? 9.0 kg) performed a progressive test for ventilatory threshold (VT) measurement and VO2max on treadmill. After 8 weeks of endurance training (3 times per week, 30 to 70 min, in different zones in respect to the ventilatory threshold) the performed the same test. Results Running velocity at ventilatory threshold increased significantly (p=0.000I), between initial and final measurements (10.88?2.09, 12.94? 1.90 km/h, respectively): as well as at VO2max H4.63?1.86, 16.44?1.59 km/h, respectively). At the initial test, velocity at ventilatory threshold was 74.11% of VO2max. At the final test, velocity at ventilatory threshold was 78.43% of VO2max. Running velocity at ventilatory threshold has significantly increased at final test (p=0.001). Discussion Running velocity at ventilatory threshold has significantly increased after eight weeks of endurance training (p -0.001), when expressed in absolute values and percentage of velocity at vo2max. Conclusion Comparison between the initial and final test demonstrated a significant increase of observed variables, under experimental conditions: at final test running velocity has increased at ventilatory threshold, in respect to absolute values and expressed as percentage at VO2max. .

The content of nitric oxide and S-nitrosothiols in rats’ liver cells under the different supplementation of macronutrient

2020 ◽  
Vol 12 (2) ◽  
pp. 187-195
Author(s):  
Halyna Kopylchuk ◽  
Ivanna Nykolaichuk ◽  
Olesiia Kuziak
Keyword(s):  
Nitric Oxide ◽  
Nitrogen Oxide ◽  
Nitrosative Stress ◽  
Liver Cells ◽  
Oxide Content ◽  
Experimental Conditions ◽  
Before And After ◽  
Rat Liver Cells ◽  
Key Factor ◽  
Excessive Consumption

This paper presents studies of nitric oxide and low-molecular S-nitrosothiols in the mitochondrial and cytosolic fractions of the rats' liver under the conditions of, alimentary protein deprivation, consumption of excess sucrose content and combined action of two adverse factors. In order to model the low-protein diet of the animal for 28 days received an isocaloric diet containing 4.7% protein, 10% fat, 81,3% carbohydrates (starch – 37%, sucrose – 30%, cellulose – 5%) and was calculated in accordance with the recommendations of the American Institute of Nutrition. The high-sugar diet consisted of 14% protein, 10% fat, 72% carbohydrates (starch – 37%, sucrose – 30%, cellulose – 5%). The mitochondrial and cytosolic fraction of rat liver cells were obtained by the method of differential centrifugation. Nitrogen oxide content was assessed by a unified method by determining the NO2- content, which is a stable metabolite of nitric oxide. Since NO is inactivated into an oxidase reaction with the conversion into nitrite or nitrate that is quickly metabolized, the nitrogen oxide content was assessed by the change in NO2-. The concentration of S-nitrosothiols was recorded, respectively, by determining the concentration of nitrite anion before and after the addition of Hg2+ ions, which by modifying the S – N bonds catalyzes the release of S-nitrosyl thiols of nitric oxide. An increase in NO content in both hepatic subcellular fractions of the rats’ experimental groups compared to control values was found. However, a lack of protein in the diet (protein deficiency in the diet leads to an increase in nitric oxide levels in 3-4 times) can be considered as a key factor in the recorded changes in the mitochondria of the animals’ liver, while in the cytosol - excessive consumption of sucrose (3-5 times increase). Regarding the level of S-nitrosothiols, in the studied fractions, multidirectional changes in their concentration were found. Thus, an increase in the content of nitrosyl derivatives in the mitochondria of rat’s liver cells with a simultaneous decrease in their level in the cytosol indicates dysmetabolic disorders in the transport system and deposition of nitric oxide, which can lead to the development of nitrosative stress under the experimental conditions.

THE USE OF POLYSTYRENE–ALLERGEN CONJUGATES FOR THE REMOVAL OF ANTIBODIES FROM SERA OF ALLERGIC INDIVIDUALS

1960 ◽  
Vol 38 (1) ◽  
pp. 1249-1253
Author(s):  
L. Gyenes ◽  
A. H. Sehon
Keyword(s):  
Hydrochloric Acid ◽  
Protein Concentration ◽  
Complete Removal ◽  
Experimental Conditions ◽  
Comparative Analyses ◽  
Before And After

Polystyrene–ragweed conjugates were shown to remove specifically antibodies from sera of individuals allergic to ragweed. This observation is considered evidence that firm combination occurs in vitro between allergic antibodies and the homologous allergens. Comparative analyses of allergic sera before and after exposure to immunosorbents indicated that complete removal of skin-sensitizing, blocking, and hemagglutinating antibodies did not result in a measurable decrease in protein concentration, thus demonstrating that these factors are present only in minute amounts.Attempts to eîute allergic antibodies from the homologous immunosorbents under various experimental conditions did not lead to their recovery in significant yields; these antibodies could be recovered in small amounts by dissociation with hydrochloric acid at pH 3.

scholarly journals Slow Late Component in Conditioned Stimulus-Evoked Potentials From the Amygdala After Fear Conditioning in the Rat

2002 ◽  
Vol 9 (4) ◽  
pp. 261-272 ◽  
Author(s):  
J. M. J. Knippenberg ◽  
E. L. J. M. van Luijtelaar ◽  
J. H. R. Maes
Keyword(s):  
Evoked Potentials ◽  
Fear Conditioning ◽  
Slow Component ◽  
Pavlovian Fear Conditioning ◽  
Late Component ◽  
Conditioning Procedure ◽  
Experimental Conditions ◽  
Before And After ◽  
Male Wistar Rats ◽  
Lateral Nucleus

Male Wistar rats were subjected to a differential Pavlovian fear conditioning procedure in which one of two tones (6 or 10 kHz) was followed by an electric shock (CS+) and the other was not (CS-). Before and after fear conditioning, we recorded the evoked potentials elicited byCS+andCS-from electrodes aimed at the lateral nucleus of the amygdala. Before conditioning, a slow, negative component with peak amplitude around 150 ms was present in the evoked potentials. This component was sensitive to habituation. After fear conditioning, bothCS+andCS-elicited the same late component, albeit with a larger amplitude. This enhancement was temporary: decreasing amplitude was observed in the course of CS test presentations under extinction. Prior research revealed a comparable slow component in the amygdala of the cat under similar experimental conditions. The collective results indicate that the large late component in the amygdala is enhanced by fear conditioning, suggesting that such enhancement reflects the anticipation of a biologically significant event.

Oxygen consumption and ventilation of dogs during passive and active exercise

1977 ◽  
Vol 42 (6) ◽  
pp. 923-927 ◽  
Author(s):  
A. K. Russo ◽  
J. Tarasantchi ◽  
M. A. Griggio
Keyword(s):  
Minute Volume ◽  
O2 Consumption ◽  
Experimental Conditions ◽  
Pentobarbital Sodium ◽  
Passive Exercise ◽  
Respiratory Parameters ◽  
Ventilatory Equivalent ◽  
Before And After ◽  
Proportional Increase ◽  
Passive Muscle

A comparison was made between the influence of passive and active exercise on the energy metabolism (EM) and respiratory parameters (RP) of dogs: respiratory minute volume and ventilatory equivalent for O2. Passive exercise was performed in 24 dogs, anesthetized with pentobarbital sodium and morphine or ketamine hydrochloride and pentobarbital sodium, by moving the four limbs at constant frequencies of 25, 45, or 80 movements/min before and after curarization. Active exercise was induced in 35 animals by electric stimulation of the quadriceps and triceps muscles or of the distal ends of femoral and radial nerves at the same frequencies previously indicated. Values obtained for EM and RP during passive exercise were not significantly different from those obtained during resting conditions; active exercise caused a significant increase which was directly proportional to the frequencies of limb movement. Our results indicate that passive muscle movement induces no alteration in O2 consumption and the possible relfexes generated in these experimental conditions were not apparently important on ventilatory control. In active movements, over the range of the frequencies studied, there is a proportional increase in O2 consumption followed by a corresponding increase in ventilation.

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