ISSN: 2456-2734

                    Curent issues

Welcome to IJPERA! International Journal of Precious Engineering Research and Applications

Current Issue (Volume 01 - Issue 02) (September 2016)


Title:
Optimization of Downstream process parameters for the purification of Docosahexaenoic acid to attain high purity.
Authors:
Umesh Luthra, Yogesh Patel, Aditi Trivedi, Mitali Lade, Alka Singh
Source:
International Journal of Precious Engineering Research and Applications, pp 01 - 04, Vol 01 - No. 02, 2016
Abstract:
Microalgae have increasingly gained research interest as a source of speciality lipids such as eicosapentanoic acid and docosahexainoic acid which are often reported to provide various health benefits. Extracting and purifying the oil from the algae continues to prove a challenge both in microalgae bioproducts and biofuel. Thecurrent study involves the optimization of the purification of Docosahexaenoic acid from fermenter broth. Thecurrent study also depicts the role of pH maintenance during the fermentation process. Intermittent feeding of liquid ammonia shows better growth and better yield...
Keywords:
Solvent extraction. Docosahexaenoic acid, Downstream processing, solvent selection
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Title:
Comparative Analysis of Different Modulation Techniques For Five Level Diode Clamped Inverter With Boost Converter
Authors:
M.V.Vinod kumar , D.Kamala
Source:
International Journal of Precious Engineering Research and Applications, pp 05 - 11, Vol 01 - No. 02, 2016
Abstract:
Now a days a Diode clamped inverter topologies are used as static VAR compensators, high voltage grid interconnections and variable speed motor drives. The objective of this paper is to balance DC link capacitor voltages and to test five level diode clamped inverter using different modulation techniques. In this paper capacitor voltage balancing is performed by a three level boost converter connected to the inner two capacitors and an additional balancing circuit is used to balance the other two capacitors and also five level diode clamped inverter is tested by using different pulse width modulation techniques. The results obtained from the MATLAB/SIMULINK is tabulated to compare the total Harmonic Distortion(THD) for different modulation techniques.
Keywords:
Five level Diode Clamped Inverter, Capacitor Voltage balancing, Three level boost converter, Modulation Index, Total Harmonic Distortion (THD).
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Title:
Recovery of Valuable Metals with Citric Acid from Red Mud
Authors:
Xiaobo Zhu, Wang Li, Sen Tang, Wenzhong Li
Source:
International Journal of Precious Engineering Research and Applications, pp 12 - 17, Vol 01 - No. 02, 2016
Abstract:
The research has focused on the recovery of valuable metals with citric acid to strengthen leaching from red mud, which is obtained from bauxite during alumina production. The main factors on the recovery of valuable metals such as sulfuric acid concentration, liquid to solid ratio, citric acid addition, leaching temperature and leaching time were investigated. The XRD pattern of red mud and leached sample were analyzed. The results show that the main phases in red mud were perovskite, brookite, muscovite, hematite, calcite, cancrinite and quartz. The recovery of titanium, vanadium, iron and aluminum reached 81.36%, 66.72%, 78.42% and 71.64% respectively under the conditions of citric acid of 5%, sulfuric acid concentration of 5 mol/L, liquid to solid ratio of 5 mL/g, temperature of 90 oC and time of 60 min. The dissolution of perovskite, brookite, hematite, cancrinite
and muscovite led to the recovery of titanium, vanadium, iron and aluminum, which could be promoted with using citric acid.
Keywords:
Red mud; Valuable metals; Citric acid; Titanium; Vanadium
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Title:
Cryptanalysis of Image Encryption Scheme Based on Chaotic Tent Map
Authors:
L. Dolendro Singh, Kh. Manglem Singh
Source:
International Journal of Precious Engineering Research and Applications, pp 18 - 22, Vol 01 - No. 02, 2016
Abstract:
With the development of chaos theory, many image encryption algorithmshave been designed using the properties associated withthechaotic map. The chaotic map shows high sensitivity to initial conditions and the sequence generated using chaotic map are unpredictable making it a good choice for performing encryption operation. But, without proper encryption algorithm design, encryption scheme designed based onthechaotic map can be cryptanalyzed to reveal the plain image. In this paper, an image encryption scheme based on chaotic tent map is cryptanalyzed using chosen-plaintext. Simulation results are shown where the plain image is successfully revealed from the cipher image without using the initial key used during encryption.
Keywords:
Chaotic tent map, chosen-plaintext attack, cryptanalysis, cryptography, image encryption
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Title:
Comparative Study between Karatsuba Algorithm and FFT Algorithm
Authors:
Siham Zoubir, Abderrahim Tragha
Source:
International Journal of Precious Engineering Research and Applications, pp 23 - 26, Vol 01 - No. 02, 2016
Abstract:
The product of polynomials and integers is an elementary operation, which intervenes in an impressive number of algorithms of the formal calculation. The efficiency of these algorithms is bases on product. To multiply two polynomials of n degree that has coefficients in a ring A, the classic method requires O(n²) operations in A. Also, the school algorithm of multiplication of two integers with n number required a number of binary operations there O(n²).We present in this article several algorithms of fast multiplication, which is Karatsuba algorithm with complexity O( n1,59 ), and Fast Fourier transform, with the complexity is essentially linear to n. The problems land on this article concern the arithmetical complexity of the multiplication of polynomials with a variable and the binary complexity of the Multiplication of integers
Keywords:
multiplication, algorithm, Karatsuba, Fast Fourier Transform (FFT
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