Search results for: and column
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 734

Search results for: and column

374 Method Development and Validation for Quantification of Active Content and Impurities of Clodinafop Propargyl and Its Enantiomeric Separation by High-Performance Liquid Chromatography

Authors: Kamlesh Vishwakarma, Bipul Behari Saha, Sunilkumar Sing, Abhishek Mishra, Sreenivas Rao

Abstract:

A rapid, sensitive and inexpensive method has been developed for complete analysis of Clodinafop Propargyl. Clodinafop Propargyl enantiomers were separated on chiral column, Chiral Pak AS-H (250 mm. 4.6mm x 5µm) with mobile phase n-hexane: IPA (96:4) at flow rate 1.5 ml/min. The effluent was monitored by UV detector at 230 nm. Clodinafop Propagyl content and impurity quantification was done with reverse phase HPLC. The present study describes a HPLC method using simple mobile phase for the quantification of Clodinafop Propargyl and its impurities. The method was validated and found to be accurate, precise, convenient and effective. Moreover, the lower solvent consumption along with short analytical run time led to a cost effective analytical method.

Keywords: Clodinafop Propargyl, method, validation, HPLC-UV

Procedia PDF Downloads 371
373 Analytical Model for Columns in Existing Reinforced Concrete Buildings

Authors: Chang Seok Lee, Sang Whan Han, Girbo Ko, Debbie Kim

Abstract:

Existing reinforced concrete structures are designed and built without considering seismic loads. The columns in such buildings generally exhibit widely spaced transverse reinforcements without using seismic hooks. Due to the insufficient reinforcement details in columns, brittle shear failure is expected in columns that may cause pre-mature building collapse mechanism during earthquakes. In order to retrofit those columns, the accurate seismic behavior of the columns needs to be predicted with proper analytical models. In this study, an analytical model is proposed for accurately simulating the cyclic behavior of shear critical columns. The parameters for pinching and cyclic deterioration in strength and stiffness are calibrated using test data of column specimens failed by shear.

Keywords: analytical model, cyclic deterioration, existing reinforced concrete columns, shear failure

Procedia PDF Downloads 265
372 Development and Total Error Concept Validation of Common Analytical Method for Quantification of All Residual Solvents Present in Amino Acids by Gas Chromatography-Head Space

Authors: A. Ramachandra Reddy, V. Murugan, Prema Kumari

Abstract:

Residual solvents in Pharmaceutical samples are monitored using gas chromatography with headspace (GC-HS). Based on current regulatory and compendial requirements, measuring the residual solvents are mandatory for all release testing of active pharmaceutical ingredients (API). Generally, isopropyl alcohol is used as the residual solvent in proline and tryptophan; methanol in cysteine monohydrate hydrochloride, glycine, methionine and serine; ethanol in glycine and lysine monohydrate; acetic acid in methionine. In order to have a single method for determining these residual solvents (isopropyl alcohol, ethanol, methanol and acetic acid) in all these 7 amino acids a sensitive and simple method was developed by using gas chromatography headspace technique with flame ionization detection. During development, no reproducibility, retention time variation and bad peak shape of acetic acid peaks were identified due to the reaction of acetic acid with the stationary phase (cyanopropyl dimethyl polysiloxane phase) of column and dissociation of acetic acid with water (if diluent) while applying temperature gradient. Therefore, dimethyl sulfoxide was used as diluent to avoid these issues. But most the methods published for acetic acid quantification by GC-HS uses derivatisation technique to protect acetic acid. As per compendia, risk-based approach was selected as appropriate to determine the degree and extent of the validation process to assure the fitness of the procedure. Therefore, Total error concept was selected to validate the analytical procedure. An accuracy profile of ±40% was selected for lower level (quantitation limit level) and for other levels ±30% with 95% confidence interval (risk profile 5%). The method was developed using DB-Waxetr column manufactured by Agilent contains 530 µm internal diameter, thickness: 2.0 µm, and length: 30 m. A constant flow of 6.0 mL/min. with constant make up mode of Helium gas was selected as a carrier gas. The present method is simple, rapid, and accurate, which is suitable for rapid analysis of isopropyl alcohol, ethanol, methanol and acetic acid in amino acids. The range of the method for isopropyl alcohol is 50ppm to 200ppm, ethanol is 50ppm to 3000ppm, methanol is 50ppm to 400ppm and acetic acid 100ppm to 400ppm, which covers the specification limits provided in European pharmacopeia. The accuracy profile and risk profile generated as part of validation were found to be satisfactory. Therefore, this method can be used for testing of residual solvents in amino acids drug substances.

Keywords: amino acid, head space, gas chromatography, total error

Procedia PDF Downloads 148
371 Extractive Fermentation of Ethanol Using Vacuum Fractionation Technique

Authors: Weeraya Samnuknit, Apichat Boontawan

Abstract:

A vacuum fractionation technique was introduced to remove ethanol from fermentation broth. The effect of initial glucose and ethanol concentrations were investigated for specific productivity. The inhibitory ethanol concentration was observed at 100 g/L. In order to increase the fermentation performance, the ethanol product was removed as soon as it is produced. The broth was boiled at 35°C by reducing the pressure to 65 mBar. The ethanol/water vapor was fractionated for up to 90 wt% before leaving the column. Ethanol concentration in the broth was kept lower than 25 g/L, thus minimized the product inhibition effect to the yeast cells. For batch extractive fermentation, a high substrate utilization rate was obtained at 26.6 g/L.h and most of glucose was consumed within 21 h. For repeated-batch extractive fermentation, addition of glucose was carried out up to 9 times and ethanol was produced more than 8-fold higher than batch fermentation.

Keywords: ethanol, extractive fermentation, product inhibition, vacuum fractionation

Procedia PDF Downloads 250
370 ANN Modeling for Cadmium Biosorption from Potable Water Using a Packed-Bed Column Process

Authors: Dariush Jafari, Seyed Ali Jafari

Abstract:

The recommended limit for cadmium concentration in potable water is less than 0.005 mg/L. A continuous biosorption process using indigenous red seaweed, Gracilaria corticata, was performed to remove cadmium from the potable water. The process was conducted under fixed conditions and the breakthrough curves were achieved for three consecutive sorption-desorption cycles. A modeling based on Artificial Neural Network (ANN) was employed to fit the experimental breakthrough data. In addition, a simplified semi empirical model, Thomas, was employed for this purpose. It was found that ANN well described the experimental data (R2>0.99) while the Thomas prediction were a bit less successful with R2>0.97. The adjusted design parameters using the nonlinear form of Thomas model was in a good agreement with the experimentally obtained ones. The results approve the capability of ANN to predict the cadmium concentration in potable water.

Keywords: ANN, biosorption, cadmium, packed-bed, potable water

Procedia PDF Downloads 430
369 Efficient Moment Frame Structure

Authors: Mircea I. Pastrav, Cornelia Baera, Florea Dinu

Abstract:

A different concept for designing and detailing of reinforced concrete precast frame structures is analyzed in this paper. The new detailing of the joints derives from the special hybrid moment frame joints. The special reinforcements of this alternative detailing, named modified special hybrid joint, are bondless with respect to both column and beams. Full scale tests were performed on a plan model, which represents a part of 5 story structure, cropped in the middle of the beams and columns spans. Theoretical approach was developed, based on testing results on twice repaired model, subjected to lateral seismic type loading. Discussion regarding the modified special hybrid joint behavior and further on widening research needed concludes the presentation.

Keywords: modified hybrid joint, repair, seismic loading type, acceptance criteria

Procedia PDF Downloads 523
368 Olefin and Paraffin Separation Using Simulations on Extractive Distillation

Authors: Muhammad Naeem, Abdulrahman A. Al-Rabiah

Abstract:

Technical mixture of C4 containing 1-butene and n-butane are very close to each other with respect to their boiling points i.e. -6.3°C for 1-butene and -1°C for n-butane. Extractive distillation process is used for the separation of 1-butene from the existing mixture of C4. The solvent is the essential of extractive distillation, and an appropriate solvent shows an important role in the process economy of extractive distillation. Aspen Plus has been applied for the separation of these hydrocarbons as a simulator; moreover NRTL activity coefficient model was used in the simulation. This model indicated that the material balances in this separation process were accurate for several solvent flow rates. Mixture of acetonitrile and water used as a solvent and 99 % pure 1-butene was separated. This simulation proposed the ratio of the feed to solvent as 1 : 7.9 and 15 plates for the solvent recovery column, previously feed to solvent ratio was more than this and the proposed plates were 30, which can economize the separation process.

Keywords: extractive distillation, 1-butene, Aspen Plus, ACN solvent

Procedia PDF Downloads 447
367 Determination of 1-Deoxynojirimycin and Phytochemical Profile from Mulberry Leaves Cultivated in Indonesia

Authors: Yasinta Ratna Esti Wulandari, Vivitri Dewi Prasasty, Adrianus Rio, Cindy Geniola

Abstract:

Mulberry is a plant that widely cultivated around the world, mostly for silk industry. In recent years, the study showed that the mulberry leaves have an anti-diabetic effect which mostly comes from the compound known as 1-deoxynojirimycin (DNJ). DNJ is a very potent α-glucosidase inhibitor. It will decrease the degradation rate of carbohydrates in digestive tract, leading to slower glucose absorption and reducing the post-prandial glucose level significantly. The mulberry leaves also known as the best source of DNJ. Since then, the DNJ in mulberry leaves had received a considerable attention, because of the increased number of diabetic patients and the raise of people awareness to find a more natural cure for diabetic. The DNJ content in mulberry leaves varied depend on the mulberry species, leaf’s age, and the plant’s growth environment. Few of the mulberry varieties that were cultivated in Indonesiaare Morus alba var. kanva-2, M. alba var. multicaulis, M. bombycis var. lembang, and M. cathayana. The lack of data concerning phytochemicals contained in the Indonesian mulberry leaves are restraining their use in the medicinal field. The aim of this study is to fully utilize the use of mulberry leaves cultivated in Indonesia as a medicinal herb in local, national, or global community, by determining the DNJ and other phytochemical contents in them. This study used eight leaf samples which are the young leaves and mature leaves of both Morus alba var. kanva-2, M. alba var. multicaulis, M. bombycis var. lembang, and M. cathayana. The DNJ content was analyzed using reverse phase high performance liquid chromatography (HPLC). The stationary phase was silica C18 column and the mobile phase was acetonitrile:acetic acid 0.1% 1:1 with elution rate 1 mL/min. Prior to HPLC analysis the samples were derivatized with FMOC to ensure the DNJ detectable by VWD detector at 254 nm. Results showed that the DNJ content in samples are ranging from 2.90-0.07 mg DNJ/ g leaves, with the highest content found in M. cathayana mature leaves (2.90 ± 0.57 mg DNJ/g leaves). All of the mature leaf samples also found to contain higher amount of DNJ from their respective young leaf samples. The phytochemicals in leaf samples was tested using qualitative test. Result showed that all of the eight leaf samples contain alkaloids, phenolics, flavonoids, tannins, and terpenes. The presence of this phytochemicals contribute to the therapeutic effect of mulberry leaves. The pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) analysis was also performed to the eight samples to quantitatively determine their phytochemicals content. The pyrolysis temperature was set at 400 °C, with capillary column Phase Rtx-5MS 60 × 0.25 mm ID stationary phase and helium gas mobile phase. Few of the terpenes found are known to have anticancer and antimicrobial properties. From all the results, all of four samples of mulberry leaves which are cultivated in Indonesia contain DNJ and various phytochemicals like alkaloids, phenolics, flavonoids, tannins, and terpenes which are beneficial to our health.

Keywords: Morus, 1-deoxynojirimycin, HPLC, Py-GC-MS

Procedia PDF Downloads 330
366 Evaluating of Design Codes for Circular High Strength Concrete-Filled Steel Tube Columns

Authors: Soner Guler, Eylem Guzel, Mustafa Gülen

Abstract:

Recently, concrete-filled steel tube columns are highly popular in high-rise buildings. The main aim of this study is to evaluate the axial load capacities of circular high strength concrete-filled steel tube columns according to Eurocode 4 (EC4) and American Concrete Institute (ACI) design codes. The axial load capacities of fifteen concrete-filled steel tubes stub columns were compared with design codes EU4 and ACI. The results showed that the EC4 overestimate the axial load capacity for all the specimens.

Keywords: concrete-filled steel tube column, axial load capacity, Eurocode 4, ACI design codes

Procedia PDF Downloads 386
365 SMRF Seismic Response: Unequal Beam Depths

Authors: Babak H. Mamaqani, Alimohammad Entezarmahdi

Abstract:

There are many researches on parameters affecting seismic behavior of steel moment frames. Great deal of these researches considers cover plate connections with or without haunch and direct beam to column connection for exterior columns. Also there are experimental results for interior connections with equal beam depth on both sides but not much research has been performed on the seismic behavior of joints with unequal beam depth. Based on previous experimental results, a series of companion analyses have been set up considering different beam height and connection detailing configuration to investigate the seismic behavior of the connections. Results of this study indicate that when the differences between beams height on both side increases, use of haunch connection system leads to significant improvement in the seismic response whereas other configurations did not provide satisfying results.

Keywords: analytical modeling, Haunch connection, seismic design, unequal beam depth

Procedia PDF Downloads 419
364 Comparison of ANN and Finite Element Model for the Prediction of Ultimate Load of Thin-Walled Steel Perforated Sections in Compression

Authors: Zhi-Jun Lu, Qi Lu, Meng Wu, Qian Xiang, Jun Gu

Abstract:

The analysis of perforated steel members is a 3D problem in nature, therefore the traditional analytical expressions for the ultimate load of thin-walled steel sections cannot be used for the perforated steel member design. In this study, finite element method (FEM) and artificial neural network (ANN) were used to simulate the process of stub column tests based on specific codes. Results show that compared with those of the FEM model, the ultimate load predictions obtained from ANN technique were much closer to those obtained from the physical experiments. The ANN model for the solving the hard problem of complex steel perforated sections is very promising.

Keywords: artificial neural network (ANN), finite element method (FEM), perforated sections, thin-walled Steel, ultimate load

Procedia PDF Downloads 352
363 Preparation, Solid State Characterization of Etraverine Co-Crystals with Improved Solubility for the Treatment of Human Immunodeficiency Virus

Authors: B. S. Muddukrishna, Karthik Aithal, Aravind Pai

Abstract:

Introduction: Preparation of binary cocrystals of Etraverine (ETR) by using Tartaric Acid (TAR) as a conformer was the main focus of this study. Etravirine is a Class IV drug, as per the BCS classification system. Methods: Cocrystals were prepared by slow evaporation technique. A mixture of total 500mg of ETR: TAR was weighed in molar ratios of 1:1 (371.72mg of ETR and 128.27mg of TAR). Saturated solution of Etravirine was prepared in Acetone: Methanol (50:50) mixture in which tartaric acid is dissolved by sonication and then this solution was stirred using a magnetic stirrer until the solvent got evaporated. Shimadzu FTIR – 8300 system was used to acquire the FTIR spectra of the cocrystals prepared. Shimadzu thermal analyzer was used to achieve DSC measurements. X-ray diffractometer was used to obtain the X-ray powder diffraction pattern. Shake flask method was used to determine the equilibrium dynamic solubility of pure, physical mixture and cocrystals of ETR. USP buffer (pH 6.8) containing 1% of Tween 80 was used as the medium. The pure, physical mixture and the optimized cocrystal of ETR were accurately weighed sufficient to maintain the sink condition and were filled in hard gelatine capsules (size 4). Electrolab-Tablet Dissolution tester using basket apparatus at a rotational speed of 50 rpm and USP phosphate buffer (900 mL, pH = 6.8, 37 ˚C) + 1% Tween80 as a media, was used to carry out dissolution. Shimadzu LC-10 series chromatographic system was used to perform the analysis with PDA detector. An Hypersil BDS C18 (150mm ×4.6 mm ×5 µm) column was used for separation with mobile phase comprising of a mixture of ace¬tonitrile and phosphate buffer 20mM, pH 3.2 in the ratio 60:40 v/v. The flow rate was 1.0mL/min and column temperature was set to 30°C. The detection was carried out at 304 nm for ETR. Results and discussions: The cocrystals were subjected to various solid state characterization and the results confirmed the formation of cocrystals. The C=O stretching vibration (1741cm-1) in tartaric acid was disappeared in the cocrystal and the peak broadening of primary amine indicates hydrogen bond formation. The difference in the melting point of cocrystals when compared to pure Etravirine (265 °C) indicates interaction between the drug and the coformer which proves that first ordered transformation i.e. melting endotherm has disappeared. The difference in 2θ values of pure drug and cocrystals indicates the interaction between the drug and the coformer. Dynamic solubility and dissolution studies were also conducted by shake flask method and USP apparatus one respectively and 3.6 fold increase in the dynamic solubility were observed and in-vitro dissolution study shows four fold increase in the solubility for the ETR: TAR (1:1) cocrystals. The ETR: TAR (1:1) cocrystals shows improved solubility and dissolution as compared to the pure drug which was clearly showed by solid state characterization and dissolution studies.

Keywords: dynamic solubility, Etraverine, in vitro dissolution, slurry method

Procedia PDF Downloads 356
362 Prediction of Oxygen Transfer and Gas Hold-Up in Pneumatic Bioreactors Containing Viscous Newtonian Fluids

Authors: Caroline E. Mendes, Alberto C. Badino

Abstract:

Pneumatic reactors have been widely employed in various sectors of the chemical industry, especially where are required high heat and mass transfer rates. This study aimed to obtain correlations that allow the prediction of gas hold-up (Ԑ) and volumetric oxygen transfer coefficient (kLa), and compare these values, for three models of pneumatic reactors on two scales utilizing Newtonian fluids. Values of kLa were obtained using the dynamic pressure-step method, while  was used for a new proposed measure. Comparing the three models of reactors studied, it was observed that the mass transfer was superior to draft-tube airlift, reaching  of 0.173 and kLa of 0.00904s-1. All correlations showed good fit to the experimental data (R2≥94%), and comparisons with correlations from the literature demonstrate the need for further similar studies due to shortage of data available, mainly for airlift reactors and high viscosity fluids.

Keywords: bubble column, internal loop airlift, gas hold-up, kLa

Procedia PDF Downloads 274
361 Toxicity and Larvicidal Activity of Cholesta-β-D-Glucopyranoside Isolated from Combretum molle R.

Authors: Abdu Zakari, Sai’d Jibril, Adoum A. Omar

Abstract:

The leaves of Combretum molle was selected on the basis of its uses in folk medicine as insecticides. The leave extracts of Combretum molle was tested against the larvae of Artemia salina, i.e. Brine Shrimp Lethality Test (BST), Culex quinquefasciatus Say (Filaria disease vector) i.e. Larvicidal Test, using crude ethanol, n-hexane, chloroform, ethyl acetate, and methanol extracts. The methanolic extract proved to be the most effective in inducing complete lethality at minimum doses both in the BST and the Larvicidal activity test. The LC50¬ values obtained are 24.85 µg/ml and 0.4µg/ml respectively. The bioactivity-guided column chromatography afforded the pure compound ACM–3. ACM-3 was not active in the BST with LC50 value >1000µg/ml, but was active in the Larvicidal activity test with LC50 value 4.0µg/ml. ACM-3 was proposed to have the structure I, (Cholesta-β-D-Glucopyranoside).

Keywords: toxicity, larvicidal, Combretum molle, Artemia salina, Culex quinquefasciatus Say.

Procedia PDF Downloads 398
360 Experimental Investigation of Absorbent Regeneration Techniques to Lower the Cost of Combined CO₂ and SO₂ Capture Process

Authors: Bharti Garg, Ashleigh Cousins, Pauline Pearson, Vincent Verheyen, Paul Feron

Abstract:

The presence of SO₂ in power plant flue gases makes flue gas desulfurization (FGD) an essential requirement prior to post combustion CO₂ (PCC) removal facilities. Although most of the power plants worldwide deploy FGD in order to comply with environmental regulations, generally the achieved SO₂ levels are not sufficiently low for the flue gases to enter the PCC unit. The SO₂ level in the flue gases needs to be less than 10 ppm to effectively operate the PCC installation. The existing FGD units alone cannot bring down the SO₂ levels to or below 10 ppm as required for CO₂ capture. It might require an additional scrubber along with the existing FGD unit to bring the SO₂ to the desired levels. The absence of FGD units in Australian power plants brings an additional challenge. SO₂ concentrations in Australian power station flue gas emissions are in the range of 100-600 ppm. This imposes a serious barrier on the implementation of standard PCC technologies in Australia. CSIRO’s developed CS-Cap process is a unique solution to capture SO₂ and CO₂ in a single column with single absorbent which can potentially bring cost-effectiveness to the commercial deployment of carbon capture in Australia, by removing the need for FGD. Estimated savings of removing SO₂ through a similar process as CS-Cap is around 200 MMUSD for a 500 MW Australian power plant. Pilot plant trials conducted to generate the proof of concept resulted in 100% removal of SO₂ from flue gas without utilising standard limestone-based FGD. In this work, removal of absorbed sulfur from aqueous amine absorbents generated in the pilot plant trials has been investigated by reactive crystallisation and thermal reclamation. More than 95% of the aqueous amines can be reclaimed back from the sulfur loaded absorbent via reactive crystallisation. However, the recovery of amines through thermal reclamation is limited and depends on the sulfur loading on the spent absorbent. The initial experimental work revealed that reactive crystallisation is a better fit for CS-Cap’s sulfur-rich absorbent especially when it is also capable of generating K₂SO₄ crystals of highly saleable quality ~ 99%. Initial cost estimation carried on both the technologies resulted in almost similar capital expenditure; however, the operating cost is considerably higher in thermal reclaimer than that in crystalliser. The experimental data generated in the laboratory from both the regeneration techniques have been used to generate the simulation model in Aspen Plus. The simulation model illustrates the economic benefits which could be gained by removing flue gas desulfurization prior to standard PCC unit and replacing it with a CS-Cap absorber column co-capturing CO₂ and SO₂, and it's absorbent regeneration system which would be either reactive crystallisation or thermal reclamation.

Keywords: combined capture, cost analysis, crystallisation, CS-Cap, flue gas desulfurisation, regeneration, sulfur, thermal reclamation

Procedia PDF Downloads 127
359 Performance of Stiffened Slender Built up Steel I-Columns

Authors: M. E. Abou-Hashem El Dib, M. K. Swailem, M. M. Metwally, A. I. El Awady

Abstract:

The present work illustrates a parametric study for the effect of stiffeners on the performance of slender built up steel I-columns. To achieve the desired analysis, finite element technique is used to develop nonlinear three-dimensional models representing the investigated columns. The finite element program (ANSYS 13.0) is used as a calculation tool for the necessary nonlinear analysis. A validation of the obtained numerical results is achieved. The considered parameters in the study are the column slenderness ratio and the horizontal stiffener's dimensions as well as the number of stiffeners. The dimensions of the stiffeners considered in the analysis are the stiffener width and the stiffener thickness. Numerical results signify a considerable effect of stiffeners on the performance and failure load of slender built up steel I-columns.

Keywords: columns, local buckling, slender, stiffener, thin walled section

Procedia PDF Downloads 319
358 Process Simulation of 1-Butene Separation from C4 Mixture by Extractive Distillation

Authors: Muhammad Naeem, Abdulrahman A. Al-Rabiah, Wasif Mughees

Abstract:

Technical mixture of C4 containing 1-butene and n-butane are very close to each other with regard to their boiling points i.e. -6.3°C for 1-butene and -1°C for n-butane. Extractive distillation process is used for the separation of 1-butene from the existing mixture of C4. The solvent is the essential of extractive distillation, and an appropriate solvent plays an important role in the process economy of extractive distillation. Aspen Plus has been applied for the separation of these hydrocarbons as a simulator. Moreover, NRTL activity coefficient model was used in the simulation. This model indicated that the material balances in this separation process were accurate for several solvent flow rates. Mixture of acetonitrile and water used as a solvent and 99% pure 1-butene was separated. This simulation proposed the ratio of the feed to solvent as 1: 7.9 and 15 plates for the solvent recovery column. Previously feed to solvent ratio was more than this and the number of proposed plates were 30, which shows that the separation process can be economized.

Keywords: extractive distillation, 1-butene, aspen plus, ACN solvent

Procedia PDF Downloads 544
357 Current Starved Ring Oscillator Image Sensor

Authors: Devin Atkin, Orly Yadid-Pecht

Abstract:

The continual demands for increasing resolution and dynamic range in CMOS image sensors have resulted in exponential increases in the amount of data that needs to be read out of an image sensor, and existing readouts cannot keep up with this demand. Interesting approaches such as sparse and burst readouts have been proposed and show promise, but at considerable trade-offs in other specifications. To this end, we have begun designing and evaluating various new readout topologies centered around an attempt to parallelize the sensor readout. In this paper, we have designed, simulated, and started testing a new light-controlled oscillator topology with dual column and row readouts. We expect the parallel readout structure to offer greater speed and alleviate the trade-off typical in this topology, where slow pixels present a major framerate bottleneck.

Keywords: CMOS image sensors, high-speed capture, wide dynamic range, light controlled oscillator

Procedia PDF Downloads 87
356 Development of 3D Particle Method for Calculating Large Deformation of Soils

Authors: Sung-Sik Park, Han Chang, Kyung-Hun Chae, Sae-Byeok Lee

Abstract:

In this study, a three-dimensional (3D) Particle method without using grid was developed for analyzing large deformation of soils instead of using ordinary finite element method (FEM) or finite difference method (FDM). In the 3D Particle method, the governing equations were discretized by various particle interaction models corresponding to differential operators such as gradient, divergence, and Laplacian. The Mohr-Coulomb failure criterion was incorporated into the 3D Particle method to determine soil failure. The yielding and hardening behavior of soil before failure was also considered by varying viscosity of soil. First of all, an unconfined compression test was carried out and the large deformation following soil yielding or failure was simulated by the developed 3D Particle method. The results were also compared with those of a commercial FEM software PLAXIS 3D. The developed 3D Particle method was able to simulate the 3D large deformation of soils due to soil yielding and calculate the variation of normal and shear stresses following clay deformation.

Keywords: particle method, large deformation, soil column, confined compressive stress

Procedia PDF Downloads 572
355 Application of Typha domingensis Pers. in Artificial Floating for Sewage Treatment

Authors: Tatiane Benvenuti, Fernando Hamerski, Alexandre Giacobbo, Andrea M. Bernardes, Marco A. S. Rodrigues

Abstract:

Population growth in urban areas has caused damages to the environment, a consequence of the uncontrolled dumping of domestic and industrial wastewater. The capacity of some plants to purify domestic and agricultural wastewater has been demonstrated by several studies. Since natural wetlands have the ability to transform, retain and remove nutrients, constructed wetlands have been used for wastewater treatment. They are widely recognized as an economical, efficient and environmentally acceptable means of treating many different types of wastewater. T. domingensis Pers. species have shown a good performance and low deployment cost to extract, detoxify and sequester pollutants. Constructed Floating Wetlands (CFWs) consist of emergent vegetation established upon a buoyant structure, floating on surface waters. The upper parts of the vegetation grow and remain primarily above the water level, while the roots extend down in the water column, developing an extensive under water-level root system. Thus, the vegetation grows hydroponically, performing direct nutrient uptake from the water column. Biofilm is attached on the roots and rhizomes, and as physical and biochemical processes take place, the system functions as a natural filter. The aim of this study is to diagnose the application of macrophytes in artificial floating in the treatment of domestic sewage in south Brazil. The T. domingensis Pers. plants were placed in a flotation system (polymer structure), in full scale, in a sewage treatment plant. The sewage feed rate was 67.4 m³.d⁻¹ ± 8.0, and the hydraulic retention time was 11.5 d ± 1.3. This CFW treat the sewage generated by 600 inhabitants, which corresponds to 12% of the population served by this municipal treatment plant. During 12 months, samples were collected every two weeks, in order to evaluate parameters as chemical oxygen demand (COD), biochemical oxygen demand in 5 days (BOD5), total Kjeldahl nitrogen (TKN), total phosphorus, total solids, and metals. The average removal of organic matter was around 55% for both COD and BOD5. For nutrients, TKN was reduced in 45.9% what was similar to the total phosphorus removal, while for total solids the reduction was 33%. For metals, aluminum, copper, and cadmium, besides in low concentrations, presented the highest percentage reduction, 82.7, 74.4 and 68.8% respectively. Chromium, iron, and manganese removal achieved values around 40-55%. The use of T. domingensis Pers. in artificial floating for sewage treatment is an effective and innovative alternative in Brazilian sewage treatment systems. The evaluation of additional parameters in the treatment system may give useful information in order to improve the removal efficiency and increase the quality of the water bodies.

Keywords: constructed wetland, floating system, sewage treatment, Typha domingensis Pers.

Procedia PDF Downloads 210
354 Bioactive Rare Acetogenins from the Red Alga Laurencia obtusa

Authors: Mohamed A. Ghandourah, Walied M. Alarif, Nahed O. Bawakid

Abstract:

Halogenated cyclic enynes and terpenoids are commonly identified among secondary metabolites of the genus Laurencia. Laurencian acetogenins are entirly C15 non-terpenoid haloethers with different carbocyclic nuclei; a specimen of the Red Sea red alga L. obtusa was investigated for its acetogenin content. The dichloromethane extract of the air-dried red algal material was fractionated on aluminum oxide column preparative thin-layer chromatography. Three new rare C12 acetogenin derivatives (1-3) were isolated from the organic extract obtained from Laurencia obtusa, collected from the territorial Red Sea water of Saudi Arabia. The structures of the isolated metabolites were established by means of spectroscopical data analyses. Examining the isolated compounds in activated human peripheral blood mononuclear cells (PBMC) revealed potent Anti-inflammatory activity as evidenced by inhibition of NFκB and release of other inflammatory mediators like TNF-α, IL-1β and IL-6.

Keywords: Red Sea, red algae, fatty acids, spectroscopy, anti-inflammatory

Procedia PDF Downloads 148
353 Methodology for Risk Assessment of Nitrosamine Drug Substance Related Impurities in Glipizide Antidiabetic Formulations

Authors: Ravisinh Solanki, Ravi Patel, Chhaganbhai Patel

Abstract:

Purpose: The purpose of this study is to develop a methodology for the risk assessment and evaluation of nitrosamine impurities in Glipizide antidiabetic formulations. Nitroso compounds, including nitrosamines, have emerged as significant concerns in drug products, as highlighted by the ICH M7 guidelines. This study aims to identify known and potential sources of nitrosamine impurities that may contaminate Glipizide formulations and assess their presence. By determining observed or predicted levels of these impurities and comparing them with regulatory guidance, this research will contribute to ensuring the safety and quality of combination antidiabetic drug products on the market. Factors contributing to the presence of genotoxic nitrosamine contaminants in glipizide medications, such as secondary and tertiary amines, and nitroso group-complex forming molecules, will be investigated. Additionally, conditions necessary for nitrosamine formation, including the presence of nitrosating agents, and acidic environments, will be examined to enhance understanding and mitigation strategies. Method: The methodology for the study involves the implementation of the N-Nitroso Acid Precursor (NAP) test, as recommended by the WHO in 1978 and detailed in the 1980 International Agency for Research on Cancer monograph. Individual glass vials containing equivalent to 10mM quantities of Glipizide is prepared. These compounds are dissolved in an acidic environment and supplemented with 40 mM NaNO2. The resulting solutions are maintained at a temperature of 37°C for a duration of 4 hours. For the analysis of the samples, an HPLC method is employed for fit-for-purpose separation. LC resolution is achieved using a step gradient on an Agilent Eclipse Plus C18 column (4.6 X 100 mm, 3.5µ). Mobile phases A and B consist of 0.1% v/v formic acid in water and acetonitrile, respectively, following a gradient mode program. The flow rate is set at 0.6 mL/min, and the column compartment temperature is maintained at 35°C. Detection is performed using a PDA detector within the wavelength range of 190-400 nm. To determine the exact mass of formed nitrosamine drug substance related impurities (NDSRIs), the HPLC method is transferred to LC-TQ-MS/MS with the same mobile phase composition and gradient program. The injection volume is set at 5 µL, and MS analysis is conducted in Electrospray Ionization (ESI) mode within the mass range of 100−1000 Daltons. Results: The samples of NAP test were prepared according to the protocol. The samples were analyzed using HPLC and LC-TQ-MS/MS identify possible NDSRIs generated in different formulations of glipizide. It was found that the NAP test generated a various NDSRIs. The new finding, which has not been reported yet, discovered contamination of Glipizide. These NDSRIs are categorised based on the predicted carcinogenic potency and recommended its acceptable intact in medicines. The analytical method was found specific and reproducible.

Keywords: NDSRI, nitrosamine impurities, antidiabetic, glipizide, LC-MS/MS

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352 Essential Oil Contents of Endemic Species Astragalus monspessulanus L. ssp. illyricus (Bernhardt) Chater

Authors: Nada Bezić, Valerija Dunkić, Rušćić Mirko

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Astragalus monspessulanus L. ssp. illyricus (Bernhardt) Chater is endemic species of Fabaceae family and belongs to hemicryptophyte. This plant grows wild in the sub-Mediterranean area. We analyzed the composition of the essential oil of stems and leaves of A. monspessulanus L. ssp. Illyricus, collected in Tijarica, near Split, Croatia. Water distilled essential oils from aerial parts of investigation plant have been analysed by GC and GC/MS using VF-5ms capillary column. The total yield of oil was 0.08%, based on dry weight of samples. Thirty-eight compounds were representing 88.5% of the total oil. This essential oil was characterized by a high concentration of cis-myrtanol (20.5%), geranyl acetate (9.6%) and phytone (6.6%). Previous research in the species A. monspessulanus have included flavoalkaloids and flavonoids composition. The present study gives additional knowledge about secondary metabolites contents on the genus Astragalus.

Keywords: essential oil, isovaleric acid, Valeriana tuberosa, geranyl acetate, phytone

Procedia PDF Downloads 170
351 An Analytical Study on the Vibration Reduction Method of Railway Station Using TPU

Authors: Jinho Hur, Minjung Shin, Heekyu Kim

Abstract:

In many places, new railway constructions in the city are being used to build a viaduct station to take advantage of the space below the line, for difficulty of securing railway site and disconnections of areas. The space under the viaduct has limited to use by noise and vibration. In order to use it for various purposes, reducing noise and vibration is required. The vibration reduction method for new structures is recently developed enough to use as accommodation, but the reduction method for existing structures is still far-off. In this study, it suggests vibration reduction method by filling vibration reduction material to column members which is path of structure-bone-noise from trains run. Because most of railroad stations are reinforced concrete structures. It compares vibration reduction of station applied the method and original station by FEM analysis. As a result, reduction of vibration acceleration level in bandwidth 15~30Hz can be reduced. Therefore, using this method for viaduct railroad station, vibration of station is expected to be reduced.

Keywords: structure borne noise, TPU, viaduct rail station, vibration reduction method

Procedia PDF Downloads 542
350 Fuel Properties of Distilled Tire Pyrolytic Oil and Its Blends with Biodiesel and Commercial Diesel Fuel

Authors: Moshe Mello, Hilary Rutto, Tumisang Seodigeng

Abstract:

Tires are extremely challenging to recycle due to the available chemically cross-linked polymer which constitutes their nature and therefore, they are neither fusible nor soluble and consequently, cannot be remoulded into other shapes without serious degradation. Pyrolysis of tires produces four valuable products namely; char, steel, tire pyrolytic oil (TPO) and non-condensable gases. TPO has been reported to have similar properties to commercial diesel fuel (CDF). In this study, distillation of TPO was carried out in a batch distillation column and biodiesel was produced from waste cooking oil. FTIR analysis proved that TPO can be used as a fuel due to the available compounds detected and GC analysis displayed 94% biodiesel concentration from waste cooking oil. Different blends of TPO/biodiesel, TPO/CDF and biodiesel/CDF were prepared at different ratios. Fuel properties such as viscosity, density, flash point, and calorific value were studied. Viscosity and density models were also studied to measure the quality of different blends.

Keywords: biodiesel, distillation, pyrolysis, tire

Procedia PDF Downloads 160
349 A Comparative Study of the Modeling and Quality Control of the Propylene-Propane Classical Distillation and Distillation Column with Heat Pump

Authors: C. Patrascioiu, Cao Minh Ahn

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The paper presents the research evolution in the propylene – propane distillation process, especially for the distillation columns equipped with heat pump. The paper is structured in three parts: separation of the propylene-propane mixture, steady state process modeling, and quality control systems. The first part is dedicated to state of art of the two distillation processes. The second part continues the author’s researches of the steady state process modeling. There has been elaborated a software simulation instrument that may be used to dynamic simulation of the process and to design the quality control systems. The last part presents the research of the control systems, especially for quality control systems.

Keywords: absorption, distillation, heat pump, Unisim design

Procedia PDF Downloads 338
348 Analytical Investigation of Replaceable Links with Reduced Web Section for Link-to-Column Connections in Eccentrically Braced Frames

Authors: Daniel Y. Abebe, Sijeong Jeong, Jaehyouk Choi

Abstract:

The use of eccentrically braced frame (EBF) is increasing day by day as EBF possesses high elastic stiffness, stable inelastic response under cyclic lateral loading, and excellent ductility and energy dissipation capacity. The ductility and energy dissipation capacity of EBF depends on the active link beams. Recently, there are two types EBFs; these are conventional EBFs and EBFs with replaceable links. The conventional EBF has a disadvantage during maintenance in post-earthquake. The concept of removable active link beam in EBF is developed to overcome the limitation of the conventional EBF in post-earthquake. In this study, a replaceable link with reduced web section is introduced and design equations are suggested. In addition, nonlinear finite element analysis was conducted in order to evaluate the proposed links.

Keywords: EBFs, replaceable link, earthquake disaster, reduced section

Procedia PDF Downloads 334
347 Seismic Soil-Pile Interaction Considering Nonlinear Soil Column Behavior in Saturated and Dry Soil Conditions

Authors: Mohammad Moeini, Mehrdad Ghyabi, Kiarash Mohtasham Dolatshahi

Abstract:

This paper investigates seismic soil-pile interaction using the Beam on Nonlinear Winkler Foundation (BNWF) approach. Three soil types are considered to cover all the possible responses, as well as nonlinear site response analysis using finite element method in OpenSees platform. Excitations at each elevation that are output of the site response analysis are used as the input excitation to the soil pile system implementing multi-support excitation method. Spectral intensities of acceleration show that the extent of the response in sand is more severe than that of clay, in addition, increasing the PGA of ground strong motion will affect the sandy soil more, in comparison with clayey medium, which is an indicator of the sensitivity of soil-pile systems in sandy soil.

Keywords: BNWF method, multi-support excitation, nonlinear site response analysis, seismic soil-pile interaction

Procedia PDF Downloads 394
346 Experimental Study on Flooding Phenomena in a Three-Phase Direct Contact Heat Exchanger for the Utilisation in Solar Pond Applications

Authors: Hameed B. Mahood, Ali Sh. Baqir, Alasdair N. Campbell

Abstract:

Experiments to study the limitation of flooding inception of three-phase direct contact condenser have been carried out in a counter-current small diameter vertical condenser. The total column height was 70 cm and 4 cm diameter. Only 48 cm has been used as an active three-phase direct contact condenser height. Vapour pentane with three different initial temperatures (40, 43.5 and 47.5 °C) and water with a constant temperature (19 °C) have been used as a dispersed phase and a continuous phase respectively. Five different continuous phase mass flow rate and four different dispersed phase mass flow rate have been tested throughout the experiments. Dimensionless correlation based on the previous common flooding correlation is proposed to calculate the up flow flooding inception of the three-phase direct contact condenser.

Keywords: Three-phase heat exchanger, condenser, solar energy, flooding phenomena

Procedia PDF Downloads 338
345 Comparison of Nucleic Acid Extraction Platforms On Tissue Samples

Authors: Siti Rafeah Md Rafei, Karen Wang Yanping, Park Mi Kyoung

Abstract:

Tissue samples are precious supply for molecular studies or disease identification diagnosed using molecular assays, namely real-time PCR (qPCR). It is critical to establish the most favorable nucleic acid extraction that gives the PCR-amplifiable genomic DNA. Furthermore, automated nucleic acid extraction is an appealing alternative to labor-intensive manual methods. Operational complexity, defined as the number of steps required to obtain an extracted sample, is one of the criteria in the comparison. Here we are comparing the One BioMed’s automated X8 platform with the commercially available manual-operated kits from QIAGEN Mini Kit and Roche. We extracted DNA from rat fresh-frozen tissue (from different type of organs) in the matrices. After tissue pre-treatment, it is added to the One BioMed’s X8 pre-filled cartridge, and the QIAGEN QIAmp column respectively. We found that the results after subjecting the eluates to the Real Time PCR using BIORAD CFX are comparable.

Keywords: DNA extraction, frozen tissue, PCR, qPCR, rat

Procedia PDF Downloads 159