Browsing by Author "Muhammad Nadeem"

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    Investigation of Ionic Behavior of Boron Doped Ceria Oxide Ion Conductors using Electrochemical Techniques
    (Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Muhammad Nadeem; CIIT/SP20-RPH-022/LHR; Dr. Ghazanfar Abbas; LHR TP 7965
    In this study, Boron Doped Ceria (BDC) ionic conductor is prepared by co-precipitation method. Three different samples with different concentrations of boric acid and cerium nitrate were synthesized with ratio B0.3Ce0.70, B0.20Ce0.80 and B0.10Ce0.90 named as BDC-1, BDC-2 and BDC-3 respectively. Sodium carbonate was used as precipitating agent in quantity 20% of total sample. Then fabricated electrolyte was sintered at the temperature 700 ℃ in the furnace. Raman analysis of the electrolyte was conducted to evaluate the vibrational and rotational modes of material. The intense peak showed the vibrational mode of cerium oxide and lower peak showed an oxygen vacancy over some range of 550-650 cm -1 . These results showed that BDC electrolyte have high oxygen vacancies with the increase in sintering temperature. FTIR results showed the formation of the Ce- O bonds, OH stretching, metal-oxide bonds and some residual material peaks. Furthermore, FTIR spectra of the ionic conductor revealed OH stretching indicating that moisture is present in the sample. The conductivity measurements showed that conductivity of BDC-2 was electrolyte 0.086 Scm -1 at 750 ℃. These results revealed that the BDC electrolyte shows high ionic conductivity at intermediate temperatures that makes it useful for SOFC application. Fuel cell performance for BDC electrolyte materials was analyzed by using BCFZ anode and LSCZ cathode and a plot of voltage was drawn. BDC-2 having medium amount of doped Boron achieved high OCV as compared to BDC-1 and BDC-3. It was observed that cerium is best conductor so, its conductive behavior elevates the OCV as compared to Gd and Sm.
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    Koszul Loops Algebraic And Topological Description
    (Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Muhammad Nadeem; SP13-PMATH-003; LHR TP 6346; Dr. Sarfraz Ahmad
    In this thesis we explore interactions between three well established fields namely Algebra, Combinatorics and Chemistry. Main idea is to solve complicated problems in one field by using comparatively easy approaches of the second. We work it out in three different ways. In the first part, we explore chemical properties of some compounds using combinatorial techniques. In recent days atomic properties of chemical structures are intensively explored using results of graph theory depending upon degrees and distances of the associated graphs. In particular, we work on one of the interesting classes of degree based indices, namely, the Zagreb indices. These indices are very useful in QSPR and QSAR studies. We compute Zagreb index, its co index and multiple index for the topological descriptors of 2-dimensional silicon carbons 𝑆𝑖2𝐶3 − 𝐼𝐼𝐼, � �𝑖𝐶3 − 𝐼𝐼𝐼. On the other hand it is of great importance to explore the irregularity of a graph in Chemistry, Pharmacy and Bio technology. We compute irregularity, total irregularity, variance and irregularity index of some networks including (𝐻𝐻𝐶 − 1), (𝐻𝐻𝐶 −2),(BSN−1),(BSN−2) and nanocone 𝑁𝐶𝑘[𝑛]. In the second part we focus on connections between Algebra and Combinatorics. We construct a family of Wilson loops of different orders with the help of additive and multiplicative groups. We associate these newly obtained algebraic structures to the graphs through link labeling. As a main result of this session we prove that the Latin square of the Wilson loop is connected with a bipartite graph. Similarly its normal sub loop of the Wilson loop is associated with the class of star graphs. Let 𝑅 = 𝑘[𝑥1,…,𝑥𝑛] be a polynomial ring in 𝑛 variables. There is one to one correspondence between set of all square free monomial ideals in 𝑅 and set of all simplicial complexes over 𝑛 vertices. The 𝑓- and ℎ-vectors of the simplicial complex ∆ play an important role to describe algebraic properties of the associated square free monomial ideal 𝐼∆. Let ∆𝑠𝑢𝑏 be subdivided simplicial complex obtained from ∆. In the last part of this thesis, we discuss the transformation maps sending the ℎ-vectors of the simplicial complex ∆ to the ℎ-vectors of the subdivided simplical complex ∆𝑠𝑢𝑏. In the end we give algebraic applications describing the primary decomposition of an ideal 𝐼𝑃 associated to the partially ordered set = 𝐶𝑖 × 𝐶𝑗 , where 𝐶𝑖 is the chain 1 < ...<