Nanomaterials-Based Electrodes for Lithium-Ion Batteries and Alcohol Fuel Cells

This dissertation describes my research on surfactant-free synthesis of nanomaterials with applications for alcohol fuel-cell electrodes, and design and fabrication of nanomaterials-based current collectors that improve the performance of lithium-ion batteries (LIBs) by replacing existing current collectors. Chapter 1 provides a background on the electroanalytical tools used in this research, and an introduction to fuel cells and LIBs. Chapter 2 describes a novel synthesis method for fabricating gold-graphene composites by laser ablation of a gold strip in water. A well-known limitation in the fabrication of a metal-graphene composite is the use of surfactants that strongly adsorb on the metal surface and consequently reduce the catalytic activity of the metal catalyst. I developed a laser ablation-based one-pot synthesis to decorate graphene with gold nanoparticles (AuNPs) in water without using any surfactants. This linker-free gold-graphene composite was successfully tested as an electrode for the electrocatalytic oxidation of alcohols. A novel electrochemical method for depositing a porous gold-polycurcumin (Au-Polycurcumin) nanocomposite on conducting surfaces is presented in chapter 3. Au-Polycurcumin showed an excellent electrocatalytic activity for oxidation of small organic molecules such as ethanol, and methanol. In chapter 4, I demonstrate that reducing the resistance at the current collector active material interface (CCAMI) is a key factor for enhancing the performance of LIBs. I show that carbon nanotubes (CNTs), either directly grown or spray-coated on Al foils, are highly effective in reducing the CCAMI resistance of traditional LIB cathode materials (LiFePO4 or LFP, and LiNi0.33Co0.33Mn0.33O2 or NMC). The vertically aligned CNT-coated electrodes exhibited energy densities as high as (1) ∼500 W h kg–1 at ∼170 W kg–1 for LFP and (2) ∼760 W h kg–1 at ∼570 W kg–1 for NMC, both with a Li metal anode. In chapter 5, I demonstrate a surfactant-free spray coating process to coat commercial cellulose-based paper with CNTs. The prepared paper-CNTs are capable of replacing the conventional aluminum foil used in LIBs. Paper-CNTs were coated with LiFePO4 as the active material and used as cathodes with Li as the anode, and the assembled LIBs showed a high energy density of 460 Wh kg-1 at a power density of 250 W kg-1

PHYTOCHEMISTRY AND PHARMACOLOGICAL BIO-ACTIVITIES OF LANNEA COROMANDELICA: A REVIEW

Lannea coromandelica is extensively employed as a medicinal herb across the globe. This research work focuses primarily on the phytochemistry, pharmaceutics, and bio-exertion of L. coromandelica. In ethnomedicine, several members of this species function as astringents, aiding in anti-oxidant, anti-inflammatory, and anti-diabetic and are helpful in other physiological functions. In addition, Lannea species’ therapeutic benefits were acknowledged in numerous scientific investigations. The conclusions derived from the current study corroborate that the therapeutic activities of L. coromandelica can be linked to the presence of a broad spectrum of secondary metabolites and bioactive phytocompounds such as phenols, flavonoids, tannins, and proteins, according to the current study. This review highlights phyto-assembly and phyto-activities such as a diuretic, cardiovascular, and bioactivities such as antiepileptic, antimicrobial, and anti-convulsant, and pharmaceutical activities such as anti-cancer, anti-diabetic, and anti-asthmatic properties

Cross-dehydrogenative coupling and oxidativeamination reactions of ethers and alcohols with aromatics and heteroaromatics

Cross-dehydrogenative coupling (CDC) is a process in which, typically, a C–C bond is formed at the expense of two C–H bonds, either catalyzed by metals or other organic compounds, or via uncatalyzed processes. In this perspective, we present various modes of C–H bond-activation at sp3 centers adjacent to ether oxygen atoms, followed by C–C bond formation with aromatic systems as well as with heteroaromatic systems. C–N bond-formation with NH-containing heteroaromatics, leading to hemiaminal ethers, is also an event that can occur analogously to C–C bond formation, but at the expense of C–H and N–H bonds. A large variety of hemiaminal ether-forming reactions have recently appeared in the literature and this perspective also includes this complementary chemistry. In addition, the participation of C–H bonds in alcohols in such processes is also described. Facile access to a wide range of compounds can be attained through these processes, rendering such reactions useful for synthetic applications via Csp3 bond activations

Enucleation of Buffalo Oocytes: A Comparison of Methods

A comparative study of three enucleation methods; enucleation by pushing out small amount of cytoplasm beneath the first polar body, enucleation by bisectioning of oocytes, and enucleation by aspiration were carried out using the oocytes of Indian buffaloes. The statistical analysis of the results revealed that, there is no significant difference between the three enucleation methods. This information would be helpful for optimization of enucleation of recipient oocyte during somatic cell nuclear transfer

Using the Medical Research Council framework for the development and evaluation of complex interventions in a theory-based infant feeding intervention to prevent childhood obesity:The baby milk intervention and trial

Introduction. We describe our experience of using the Medical Research Council framework on complex interventions to guide the development and evaluation of an intervention to prevent obesity by modifying infant feeding behaviours. Methods. We reviewed the epidemiological evidence on early life risk factors for obesity and interventions to prevent obesity in this age group. The review suggested prevention of excess weight gain in bottle-fed babies and appropriate weaning as intervention targets; hence we undertook systematic reviews to further our understanding of these behaviours. We chose theory and behaviour change techniques that demonstrated evidence of effectiveness in altering dietary behaviours. We subsequently developed intervention materials and evaluation tools and conducted qualitative studies with mothers (intervention recipients) and healthcare professionals (intervention deliverers) to refine them. We developed a questionnaire to assess maternal attitudes and feeding practices to understand the mechanism of any intervention effects. Conclusions. In addition to informing development of our specific intervention and evaluation materials, use of the Medical Research Council framework has helped to build a generalisable evidence base for early life nutritional interventions. However, the process is resource intensive and prolonged, and this should be taken into account by public health research funders. This trial is registered with ISRTCN: 20814693 Baby Milk Trial

Synthesis, Spectral, and Biological Properties of Copper(II) Complexes of Thiosemicarbazones of Schiff Bases Derived from 4-Aminoantipyrine and Aromatic Aldehydes

We have synthesized a novel series of Schiff bases by condensation of 4-aminoantipyrine and various aromatic aldehydes followed by reaction with thiosemicarbazide. These thiosemicarbazones are potential ligands toward transition metal ions. The reaction of copper(II) salts with 4[N-(benzalidene)amino]antipyrinethiosemicarbazone (BAAPTS), 4[N-(4′-methoxybenzalidene) amino] antipyrinethiosemicarbozone (MBAAPTS), 4[N-(4′-dimethylamino benzalidene) amino] antipyrinethiosemicarbazone (DABAAPTS), and 4[N-(cinnamalidene) amino] antipyrinethiosemicarbazone (CAAPTS) resulted in the formation of solid complexes with the general composition CuX(2) · (H(2)O)(L)(X = Cl, Br,NO(3),NCS, or CH(3)COO; L = BAAPTS, MBAAPTS, DABAAPTS, or CAAPTS). These complexes were characterized through elemental analysis, molecular weight, electrical conductance, infrared, electronic spectra, and magnetic susceptibilities at room temperature. Copper(II) complexes with BAAPTS and MBAAPTS were screened for antibacterial and antifungal properties and have exhibited potential activity. Thermal stabilities of two representative complexes were also investigated

Complexes of Benzoylisonicotinic Acid Hydrazide with VO(II), Mn(II), Co(II), Ni(II), Cu(II) & Zn(II)

181-18

Complexes of VO(IV), Mn(II), Co(II), Ni(II), Cu(II) & Zn(II) with N-Acetyl-N' –isonicotinoylhydrazine

325-32