|Title: Effect of Hydrocarbon Chain Length Surfactants on Particle Size of SWy-1 Montmorillonite Suspensions|
|Author(s): Silvano Rodrigo VALANDRO, Patrícia Coelho LOMBARDO, Alessandra Lima POLI, Clarice Emi SAKODA, Carla Cristina Schmitt CAVALHEIRO|
|Pages: 1-6||Paper ID: 135406-7575-IJBAS-IJENS||Published: December, 2013|
Abstract: This paper reports the effect of the length of the alkyl chain of alkylammonium surfactants (C8, C10, C12, C14, C16, C18) on stability and particle size of the SWy-1 Mt suspensions. The particle size of these materials has been analyzed by DLS (Dynamic Light Scattering) and showed no significant change at low surfactant concentrations (~1.2% CEC). In this range of surfactant loadings (0.6 to 12% CEC), the zeta potential remains almost constant, suggesting an ion exchange mechanism. For C8 and C12 surfactants, the results using loading of 12% of CEC show increasing of the proportion of the smallest particles. Considering SWy-1 Mt suspension with C16 (12% CEC), the particle size decreases with the time. This can be attributed to adsorption of surfactant molecules on the external surface and the migration of these molecules to interlayer spaces promoting delamination effect. At higher concentrations of surfactants (95% CEC) zeta potential is close to the pzc (point of zero charge), so flocculation takes place. Comparing the delamination behaviour it is possible to observe that surfactants with larger chain lengths, such as C16, promote a more effective breaking of the layers.
|Keywords: Surfactants, clay mineral, DLS, Zeta potential.|
|Full Text (.pdf) | 454 KB|
|Title: A New Approach to Moments Inequalities for NRBU and RNBU Classes With Hypothesis Testing Applications|
|Author(s): L. S. Diab|
|Pages: 7-13||Paper ID: 132506-9494-IJBAS-IJENS||Published: December, 2013|
Abstract: In this article, new moment inequalities are derived for new renewal better than used (NRBU) and renewal new better than used (RNBU) classes of life distributions demonstrateing that if the mean life is finite for any of them, then all higher order moments exist. Next, based on these inequalities, new testing procedures for testing exponentiality against any one of the above classes are introduced and studied showing that they are simpler than most earlier ones and hold high efficiency for some commonly used alternatives and compared the two testes relative to the tests of Mahmoud et al (2002) and (2003). The power and critical values of the proposed statistic are calculated. Real examples are presented to elucidate the use of the proposed tests for practical reliability analysis. Finally,the problem in case of right censored data is also handled with some applications.
|Keywords: New renewal better than used (NRBU), renewal new better than used (RNBU), moments, -Statistic, life testing, efficiency, Monte Carlo method, power and censored data.|
|Full Text (.pdf) | 436 KB|
|Title: Water Plants Characteristic for Phytoremediation of Acid Mine Drainage Passive Treatment|
|Author(s): Herniwanti, Priatmadi. J. B, Yanuwiadi. B, Soemarno|
|Pages: 14-20||Paper ID: 136706-2525-IJBAS-IJENS||Published: December, 2013|
Abstract: This study aims to determine the best type of local plants as aquatic plants phytoremediation candidate in acid mine water management system with a passive model of wetland / aerobic wetland rise by testing several kinds of local plants around the coal mines as a medium of Phytoremediation. System used multilevel methods to be more effective in lowering the levels of acid, metals absorb capability and in accordance with the characteristics of each of these plants. Local plants used in order to found a new species that is easy to apply in the field and also to reduce costs and also more friendly to the surrounding ecosystem-especially in the coal mining company in South Kalimantan and generally in Indonesia. Management of acid mine water by means phytoremediation using aerobic wetland system to test 5 different water plants as candidates who are at the mine, namely: 1. Eleocharis dulcis, 2.Cyperus odoratus, 3.Hydrilla Vercilata, 4.Ipomea aquatic, 5. Pistia Stratatiotes with a retention period of each plant for 29 demonstrate the ability to reduce the acid levels in the water to raise the pH of acid mine average of 41% and lower levels of iron (Fe) with an average index bioremediation 7% and lower levels of manganese (Mn) with an average of 19% index bioremediation. The best candidates phytoremediation plants to lower acid levels by raising the pH is Kale Water (Ipomea aquatic) to raise the pH of 53%. To reduce levels of iron in acid mine water is to use Eleocharis dulcis reduce levels of iron (Fe) 70% to reduce manganese from the water so it is Pistia Stratatiotes lower levels of manganese (Mn) as much as 55%.
|Keywords: Acidity of acid mine drainage, phytoremediation of wetlands, local water plant, metal content of iron and manganese, index bioremediation.|
|Full Text (.pdf) | 761 KB|
|Title: Lean Six Sigma in Food Industry|
|Author(s): Kostic-Nikoli. S., Nikolic, I.|
|Pages: 21-30||Paper ID: 135906-8484-IJBAS-IJENS||Published: December, 2013|
Abstract: It has been widely investigated that the application of operations management techniques is not only based on technical factors, but it is mainly associated with organizational factors such as culture, previous policies and procedures, etc. A very good example of promisng operations practices is Lean Six Sigma (L6s). The main research question for L6s is related to its liabilities regarding its implementation and how to do it in food industry. Therefore, this paper aims to explore the impact of the new tool L6s and explain what are the critical factors related to applying L6s. The context of the analysis is in the general view of food industry. Since it seems that it has been neglected from the literature that mainly focuses is on manufacturing and service sector (telecommunication; healthcare and airline industry). The methodology was based on the structure interviews, of the 16 companies in Europe in food sector. The 16 top- managers will be exanimated on adequate way. The findings and results will help to give appropriate justifications, such as why food industries must apply L6s. And also give occasion to compare with the literature review and theory. On the end it will show that there are ten (10) particular factors that influence the implementation of L6s in food industry.
|Keywords: Lean Six Sigma, Key-Success Factors, Managers, Food Industry.|
|Full Text (.pdf) | 623 KB|