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Fort Lewis, OK, United States

Oral Roberts University , based in Tulsa, Oklahoma, in the United States, is an interdenominational, Christian, comprehensive liberal arts university with an enrollment of about 3,335 students. Founded in 1963, the university is named after its late founder, evangelist Oral Roberts.The school fronts on South Lewis Avenue between East 75th Street and East 81st Street in South Tulsa. Sitting on a 263-acre campus, ORU is accredited by the Higher Learning Commission of the North Central Association of Colleges and Schools , and offers over 60 undergraduate degree programs along with a number of masters and doctoral degrees. ORU is classified as Master's University by the Carnegie Foundation for the Advancement of Teaching. ORU was also ranked as one of 123 institutions in the 2012 "Best in the West" regional list produced by The Princeton Review. Wikipedia.

Ma X.,Oral Roberts University | Zhang J.,University of Tulsa | Yin X.,Duke University | Trivedi K.S.,Duke University
IEEE Transactions on Vehicular Technology

IEEE-and ASTM-adopted dedicated short-range communications (DSRC) standards are key enabling technologies for the next generation of vehicular safety communications. Vehicle-safety-related communication services, which require reliable and fast message delivery, usually demand broadcast communications in vehicular ad hoc networks (VANETs). In this paper, we propose and justify a distributive cross-layer scheme for the design of the control channel in DSRC with three levels of broadcast services that are critical to most potential vehicle-safety-related applications. The new scheme for enhancing broadcast reliability includes preemptive priority in safety services, dynamic receiver-oriented packet repetitions for one-hop emergency warning message dissemination, a multifrequency busy tone and minislot within the distributed interframe space (DIFS) in IEEE 802.11, and robust distance-based relay selection for multihop broadcast of emergency notification messages. Compared with a current draft of IEEE 802.11p and other schemes for DSRC safety-related services, the scheme proposed in this paper is more robust and scalable and easy to implement. Additionally, we investigate the reliability and performance of the proposed broadcast scheme for DSRC VANET safety-related services on the highway analytically and by simulations. The analytic model accounts for the impact of the hidden terminal problem, the fading channel conditions, varied message arrival intervals, and the backoff counter process on reliability and performance. © 2011 IEEE. Source

Sharma Y.C.,Banaras Hindu University | Singh B.,Banaras Hindu University | Korstad J.,Oral Roberts University
Energy and Fuels

Recycled chicken eggshells after calcination have been used as a nonconventional heterogeneous catalyst for biodiesel synthesis from karanja oil from the pongam tree (Pongamia pinnata). The catalyst was characterized on X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and differential thermal analysis/thermogravimetric analysis (DTA/TGA). The formation of the calcium oxide phase was confirmed at 900 °C after calcination. A high biodiesel yield of 95.0% and conversion of 97.4% was obtained at an 8:1 (alcohol/oil) molar ratio, 2.5 wt % catalyst, and 2.5 h reaction time at 65 ± 0.5 °C. The biodiesel conversion was determined by Fourier transform nuclear magnetic resonance (FTNMR) spectroscopy. © 2010 American Chemical Society. Source

Sharma Y.C.,Banaras Hindu University | Singh B.,Banaras Hindu University | Korstad J.,Oral Roberts University

Heterogeneous catalysts are now being tried extensively for biodiesel synthesis. These catalysts are poised to play an important role and are perspective catalysts in future for biodiesel production at industrial level. The review deals with a comprehensive list of these heterogeneous catalysts which has been reported recently. The mechanisms of these catalysts in the transesterification reaction have been discussed. The conditions for the reaction and optimized parameters along with preparation of the catalyst, and their leaching aspects are discussed. The heterogeneous basic catalyst discussed in the review includes oxides of magnesium and calcium; hydrotalcite/layered double hydroxide; alumina; and zeolites. Yield and conversion of biodiesel obtained from the triglycerides with various heterogeneous catalysts have been studied. © 2011 Elsevier Ltd All rights reserved. Source

Sharma Y.C.,Banaras Hindu University | Singh B.,Banaras Hindu University | Korstad J.,Oral Roberts University
Green Chemistry

Microalgae are being considered as a viable feedstock for large-scale production of biodiesel. However, though it may look simpler to obtain lipids from microalgae, the overall process of choosing an algal strain, cultivation, harvesting, dewatering, and extraction of oil is quite complicated and not economically prudent at this time. A thorough understanding of algae and the overall biodiesel production process discussed in this paper is vital so that focused research might lower the costs involved. Various diverse species of microalgae are currently being used as feedstocks for biofuel. Heterotrophic culture may be preferred over photoautotrophic cultivation. For cultivation, specially fabricated photobioreactors (PBRs) have the capability to overcome the constraints and limitations of the open raceway ponds, although the former are cost intensive as compared to the latter. Exergy analysis of algal-biodiesel-carbon dioxide cycle shows the overall process to be renewable and hence should attain global attention. This journal is © The Royal Society of Chemistry. Source

Sharma Y.C.,Banaras Hindu University | Singh B.,Banaras Hindu University | Korstad J.,Oral Roberts University
Biofuels, Bioproducts and Biorefining

Solid acid (heterogeneous) catalysts have a unique advantage in esterification and transesterification reactions which enhances the use of high acid value oil to be used as feedstock for synthesis of biodiesel. Various solid acid catalysts such as resins, tungstated and sulfated zirconia, polyaniline sulfate, heteropolyacid, metal complexes, sulfated tin oxide, zeolite, acidic ionic liquid, and others have been explored as potential heterogeneous catalysts. The activity of the catalyst differs slightly resulting in moderate to high conversion and yield. The reuse of the solid catalyst is governed by their deactivation, poisoning, and the extent of leaching in the reaction medium. The applicability of these catalysts for synthesis of biodiesel along with their reusability aspect is discussed in this review. © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd. Source

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