Retraction Note: Relationship between water content,shear deformation,and elastic wave velocity through unsaturated soil slope

Bulletin of Engineering Geology and the Environment -     

Two‐phase flow behavior in microtube reactors during biodiesel production from waste cooking oil

Flow patterns in the course of transesterification of waste cooking oil (WCO), sunflower oil (SFO) with water and/or oleic acid as a model of WCO, and pure SFO in the presence of a KOH catalyst in microtubes were investigated. FAME yield for the transesterification of WCO reached more than 89% in the microtube reactors with a residence time of 252 s at 333 K. The flow patterns when using WCO were changed from a liquid–liquid slug flow at the inlet region to a parallel flow at the middle region, and then to a homogeneous liquid flow at the outlet region as the reaction proceeded at 333 K. Fine droplets containing glycerol and methanol generally formed in oil slugs when using pure SFO, but were almost unobservable when using WCO. The soap produced from free fatty acids was considered to be the main factor affecting the flow patterns of WCO and SFO. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

Effects of gating design on structural and mechanical properties of high manganese steel by optimizing casting process parameters

Journal of Mechanical Science and Technology - The impacts of gating design and riser system on structure-property relationship of high manganese steel specimens produced by CO2 sand molding...     

Fatigue behavior of X40CrMoV 51 at high temperatures

The fatigue characteristics of the hot work tool steel X40CrMoV 51 (UNS number T20811) at high temperatures is presented. The temperatures for the experiments were chosen between 50–600 °C. The experiments used B-type cylindrical specimens machined from X40CrMoV in an R.R. Moore rotating bending type fatigue test machine obeying the high cycle principle. The temperature intervals for the experiments were chosen as 50, 100, 200, 300, 400, 500, and 600 °C, for which the fatigue limit for each interval at 2 × 10⁶ cycles was determined. The fatigue limit of the material at room temperature (RT) is observed as 432 MPa, whereas it drops to 383 MPa at 400 °C. On the other hand, it stays almost constant between 400–600 °C, indicating that the material includes the elements forming strong carbides such as V, Mo, and Cr, which prevent the decrease of the fatigue limit due to higher temperatures.     

Web Support System for Business Intelligence in Small and Medium Enterprises

Last decade belongs to business intelligence (BI) because it is one of the few concepts that have actually lived to the expectations. Not only the businesses have adopted it but also have reaped the fruits out of it. But the cost of BI solutions is very high and has restricted small and medium enterprises to use BI solutions. The human resource is also limited and resultantly expensive in this field. This research proposes a web support system for business intelligence which provides automated data mapping and loading from user application to BI framework and also validates it. The system also assists users in getting the outputs in terms of reports and dashboards. The implementation of the proposed framework demonstrates convenience of use and effective cost saving as it does not require any technical expertise. The beauty of this web support system is that all the steps are menu driven and any non-technical user can get hold of it easily.     

Coal gasification in CO2 atmosphere and its kinetics since 1948: A brief review

Numerous coal gasification studies have been found in the literature those employed various kinds of gasifying agents such as steam and carbon dioxide. These studies are featured with wide variations in the parametric conditions and the usage of equipments. Steam is frequently employed as a gasifying agent, however, in several studies carbon dioxide has also been used as a gasifying agent either pure or in combination with other gasifying agents (H₂O, O₂, CO, H₂). This paper is a brief review of the coal gasification with CO₂ as a diluent. Different factors were studied over the coal gasification with CO₂ such as coal rank, pressure, temperature, gas composition, catalyst and the minerals present inside the coal, heating rate, particle size, and diverse reactor types. It also deals with the application of the gas-solid models developed in the literature and the combustion and gasification mechanisms for O₂/CO₂ streams. Moreover, it reviews the kinetics and the reaction rate equations (Arrhenius and Langmuir-Hinshelwood types) for coal-char gasification both in the reaction kinetic control region (low temperature) and the diffusion control region (high temperature) and at both low and high pressures.     

Determining optimum tilt angles and orientations of photovoltaic panels in Sanliurfa, Turkey

The performance of a photovoltaic (PV) panel is affected by its orientation and its tilt angle with the horizontal plane. This is because both of these parameters change the amount of solar energy received by the surface of the PV panel. A mathematical model was used to estimate the total solar radiation on the tilted PV surface, and to determine optimum tilt angles for a PV panel installed in Sanliurfa, Turkey. The optimum tilt angles were determined by searching for the values of angles for which the total radiation on the PV surface was maximum for the period studied. The study also investigated the effect of two-axis solar tracking on energy gain compared to a fixed PV panel. This study determined that the monthly optimum tilt angle for a PV panel changes throughout the year with its minimum value as 13° in June and maximum value as 61° in December. The results showed that the gains in the amount of solar radiation throughout the year received by the PV panel mounted at monthly optimum tilt angles with respect to seasonal optimum angles and tilt angel equal to latitude were 1.1% and 3.9%, respectively. Furthermore, daily average of 29.3% gain in total solar radiation results in an daily average of 34.6% gain in generated power with two-axis solar tracking compared to a south facing PV panel fixed at 14° tilt angle on a particular day in July in Sanliurfa, Turkey.