Noble Metal based Catalysts for Natural Gas Steam Reforming Activity, Endurance and Kinetics

This thesis illustrates catalytic activity, stability and intrinsic kinetics of methane steam reforming (MSR) reaction over noble metal catalysts. The main objective of this thesis is to evaluate a best performing catalyst based on the maximization of H2 production and minimization of CO in the synthesis gas produced from MSR reaction. The noble metal catalysts tested towards MSR reaction were Rh, Ru and Pt supported on different reducible and irreducible oxides. The oxides (CeO2, MgO and Al2O3) used in this work were synthesized from their nitrite precursor by Simultaneous combustion synthesis (SCS) while Nb2O5 was prepared by heat treatment of Niobic acid obtained from Companhia Brasileira de Metalurgia e Mineracão (CBMM, Brasil). In all the catalysts the noble metals were deposited on the support by wetness impregnation method, except Pt/CeO2 which was prepared by one shoot SCS method. All the prepared catalysts were calcined under different calcination regimes. The best performing catalysts were characterized by different techniques BET, CO chemisorption, porosiometery, XRD, XPS, ICP, TEM and SEM analyses. Efforts have been made to correlate the catalytic activity with the physical characterization. All the catalysts prepared were initially screened by MSR reaction in a tubular fixed bed quartz reactor of 4mm ID containing 30mg of catalyst diluted with 50mg of inert. For catalytic screening and stability test the feed was introduced at a weight hourly space velocity of 20 NLh-1g-1cat and steam to carbon ratio 3-4 depending upon the catalyst. The results obtained from basic screening of the catalysts were analyzed in terms of methane conversion, H2 produced in dry reformate and CO2 selectivity. Among all the catalysts tested towards MSR only two were chosen based on initial screening, Rh/CeO2 and Pt/CeO2, for the further test concerning catalyst stability. The stability of Rh/CeO2 and Pt/CeO2 catalysts was determined based on daily start up and shut down cycle (DSS) with a 6h performance period. The Pt/CeO2 catalyst was tested for a total of 150 h in which 100h performance was with DSS in N2 environment while 50h of catalyst activity with DSS in reaction environment. The Rh/CeO2 catalyst was tested for a total of 25 h catalyst activity with DSS in N2 environment. Additionally the Rh/CeO2 catalyst was also tested in 100h continuous ageing. Both the catalysts showed good results in terms of catalyst activity and stability during the time period. As Rh/CeO2 catalyst showed good activity during 100h continuous endurance this catalysts was chosen to evaluate the intrinsic kinetics of methane steam reforming. For the kinetics test firstly the heat and mass transfer limitations were evaluated both experimentally and theoretically. The reactor was operated in an integral mode and no inert was used in feed for the kinetic experiments. The effect of WHSV at constant S/C 3 on the methane conversion and product composition was also determined. The partial pressures of the reactants were varied by varying the steam-to-carbon ratio of the feed. An attempt was made to fit kinetic data obtained using the models available in literature. The kinetic data obtained was perfect fit for the model proposed by Berman, and the activation energy of Rh/CeO2 was found to be 38.6 kJ/mol

Feedback Practices and Accounting Students’ Satisfaction

This paper explores the accounting feedback practices adopted by the teachers and students’ satisfaction about that feedback. Data was collected from three different departments of Bahauddin Zakariya University, Multan. Results suggested that 64% students are broadly agreed with the feedback provided to them by accounting teachers. This study tells that accounting students prefer constructive feedback, than individualized feedback, than timely feedback and then detailed feedback. This variation is because of different assessment methods adopted by accounting teachers.

Coherence enhanced quantum-dot heat engine

We show that quantum coherence can enhance the performance of a continuous quantum heat engine in the Lindblad description. We investigate the steady-state solutions of the particle-exchanging quantum heat engine, composed of degenerate double quantum dots coupled to two heat baths in parallel, where quantum coherence may be induced due to interference between relaxation channels. We find that the engine power can be enhanced by the coherence in the nonlinear response regime, when the symmetry of coupling configurations between dots and two baths is broken. In the symmetric case, the coherence cannot be maintained in the steady state, except for the maximum interference degenerate case, where initial-condition-dependent multiple steady states appear with a dark state

Effects of Moringa oleifera leaf extract on morphological and physiological growth of cassava and its efficacy in controlling Zonocerus variegatus

Zonocerus variegatus infestation has been found to cause a lot of devastation in the production of cassava crop plants in tropical and subtropical areas. Understanding the efficacy of Moringa oleifera leaf extract on controlling Z. variegatus is desired. The present study was conducted in the Department of Crop Science experimental site, Faculty of Agriculture, University of Nigeria, Nsukka to investigate the effects of M. oleifera leaf extract (MLE) on the morphological and physiological growth characteristics of cassava (Manihot utilissima Pohl.); and its efficacy as organic insecticide for controlling Z. variegatus infestation. M. oleifera leaf extract diluted in water at the volume to volume (v/v) ratios of 1:10, 1:20, 1:30 and 1:40 were applied weekly while “Uppercut (R)” (30 g dimethoate plus 250 g cypermethrin), used as water emulsifiable concentrate, was applied at the rate of 0.2 a.i./ha at three-weekly interval for two months. Result shows that M. oleifera leaf extract (MLE) dilution at the ratio of 1:30 MLE in water gave the highest percentage stem height difference (%SHD) at 32 weeks after planting with a value of 20.5% followed by 1:20 (17.8%), 1:10 (10.56%), dimethoate plus cypermethrin (8.98%) and 1:40 (8.05%). The control had the least %SHD and %LND. Dimethoate plus cypermethrin treatment was more efficacious as it eradicated the insects and caused significant (p < 0.05) increase in the number of leaves and reduction in the percentage leaf abscission especially from the thirtieth week after planting. However a combined use of Dimethoate plus cypermethrin and M. oleifera leaf extract may give a better result and as such recommended than a single treatment application

Current Scenario of Environmental Pollution & Its Solution by Plantation In Changing Climate

Life’s quality is depending on quality of environment. As environment creates favorable surroundings for survival, growth and development of existing organisms. All living organisms are affected indirectly or directly due to environmental pollution. It is due to rapid increases in human being. Environmental pollution especially by anthropogenic activities is a main problem facing the world today and there is a need for increasing attentiveness that a clean and green environment is essential for better growth of living organisms in this changing climate of World. It is our top most priority to keep our country clean and green as cleanness is a part of our faith. Thus environmental pollution is causing great threat to plants, animals and to human all over the world. As each and every problem has a solution, because problem is always artificial, man desires to find the solution. In recent innovations there is a need to develop clean and green spaces within and around the polluted areas for existence of better environment. As some plants can act as pollution sink working as natural lungs. So,“the green revolution (Plantation) is the best solution to arrest the pollution”. If haphazard population growth goes on increasing without realizing the importance of trees especially those which act as pollution sink then there would be more critical changes for living organisms in near coming futur

GROWTH PERFORMANCE AND FEED CONVERSION RATIO (FCR) OF HYBRID FINGERLINGS (CATLA CATLA X LABEO ROHITA) FED ON COTTONSEED MEAL, SUNFLOWER MEAL AND BONE MEAL

An experiment was conducted in six glass aquaria to study the growth performance and feed conversion ratio (FCR) of hybrid fingerlings (Catla catla x Labeo rohita) fed on sunflower meal, cottonseed meal and bone meal. Two replicates for each ingredient were followed. The feed was supplied at the rate of 4% of wet body weight of fingerlings twice a day. The hybrid (Catla catla x Labeo rohita) fingerlings gained highest body weight (1.62 ± 0.0 g) on sunflower meal, followed by cottonseed meal (1.61 ± 0.01 g) and bone meal (1.52 ± 0.0 g). The total length obtained by hybrid fish was 6.35 ± 0.05 cm on sunflower meal, 6.12 ± 0.05 cm on cottonseed meal and 5.85 ± 0.05 cm on bone meal. The overall mean values of FCR were lower (better) on sunflower meal (1.78 ± 0.05), followed by cottonseed meal (2.17 ± 0.01) and bone meal (2.46 ± 0.01). Thus, The sunflower meal and cottonseed meal, on the basis of growth performance and better FCR, can be included in the feed formulation for hybrid fingerlings

Efficient discontinuous finite difference meshes for 3-D Laplace-Fourier domain seismic wavefield modelling in acoustic media with embedded boundaries

Simulation of acoustic wave propagation in the Laplace?Fourier (LF) domain, with a spatially uniform mesh, can be computationally demanding especially in areas with large velocity contrasts. To improve efficiency and convergence, we use 3-D second- and fourth-order velocitypressure finite difference (FD) discontinuous meshes (DM). Our DM algorithm can use any spatial discretization ratio between meshes. We evaluate direct and iterative parallel solvers for computational speed, memory requirements and convergence. Benchmarks in realistic 3-D models and topographies show more efficient and stable results for DM with direct solvers than uniform mesh results with iterative solvers

Morphologie verbale du Mvùmbò

PL8021.C35, ISO 639-3 : nmg, Cameroon --Language

Lipid profile of Type 2 Diabetes patients attending Irrua Specialist Teaching Hospital Irrua, Edo State, Nigeria

This study investigated the lipid profile (LP) of type-2 diabetics and non-diabetic patients presenting at Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria, with a view to assessing the risk of cardiovascular disease among the diabetics. Twenty (20) diabetic and 20 non-diabetic patients (control) formed the study population. Total cholesterol (TC), triacylglycerol (TG), high density lipoprotein-cholesterol (HDL-C), and low density lipoproteincholesterol (LDL-C) were assayed for each group using standard biochemical methods, while the fasting blood glucose levels of the patients were assayed using the glucose oxidase method. The results showed higher mean TC and HDL-C levels among the diabetic patients than their non-diabetic counterparts and the observed differences were statistically significant (p<0.05). The mean glucose, TG, and LDL-C were equally higher among the diabetics than their non-diabetic counterparts, but in this instance, the differences were not statistically significant (P>0.05). Regardless of the high lipid profile levels among the diabetics, the values obtained fell within acceptable range; suggesting that the patients were responding to treatment or life style changes.Keywords: Lipid Profile, Type-2 Diabetes, Cardiovascular Disease, Teaching Hospita

Blockchain-based Perfect Sharing Project Platform based on the Proof of Atomicity Consensus Algorithm

The Korean government funded 12.8 billion USD to 652 research and development (R&D) projects supported by 20 ministries in 2019. Every year, various organizations are supported to conduct R&D projects focusing on selected core technologies by evaluating emerging technologies which industries are planning to develop. To manage the whole cycle of national R&D projects, information sharing on national R&D projects is very essential. The blockchain technology is considered as a core solution to share information reliably and prevent forgery in various fields. For efficient management of national R&D projects, we enhance and analyse the Perfect Sharing Project (PSP)-Platform based on a new blockchain-based platform for information sharing and forgery prevention. It is a shared platform for national ICT R&D projects management with excellent performance in preventing counterfeiting. As a consensus algorithm is very important to prevent forgery in blockchain, we survey not only architectural aspects and examples of the platform but also the consensus algorithms. Considering characteristics of the PSP-Platform, we adopt an atomic proof (POA) consensus algorithm as a new consensus algorithm in this paper. To prove the validity of the POA consensus algorithm, we have conducted experiments. The experiment results show the outstanding performance of the POA consensus algorithm used in the PSP-Platform in terms of block generation delay and block propagation time