Different Supervised Machine Learning Methods For Predicting And Analyzing the Diabetes

Abstrac

Investigations of the Growth Kinetics of Capped CdSe and CdS Nanocrystals by a Combined Use of Small Angle X-ray Scattering and Other Techniques

The growth of capped CdSe and CdS nanocrystals formed by the reaction of selenium or sulfur with cadmium stearate in toluene solution in the presence of dodecanethiol or trioctylphosphine oxide and tetralin, has been investigated by a variety of techniques to obtain reliable data. Whereas small angle X-ray scattering has provided statistically satisfactory data on the variation of size distribution with time, TEM has been used as a direct probe of the particle size, although with a limited sampling size. UV/Vis and photoluminescence spectroscopies have also provided information about the time evolution of the average diameter (D) of the nanocrystals. By employing all these techniques, we have obtained the D(t) data and fitted then to various growth models. Although certain qualitative observations suggest growth of the nanocrystals to be controlled by diffusion-limited Ostwald ripening, we have found it is necessary to include the surface reaction term in the growth equation. Thus, the growth of CdSe and CdS nanocrystals has contributions from both diffusion and surface reaction, with a $D^3-D^2$ type behavior, independent of the capping agent

Growth Kinetics of Nanocrystals and Nanorods by Employing Small-angle X-ray Scattering (SAXS) and Other Techniques

In this article, we report the results of our detailed investigations of the growth kinetics of zero-dimensional nanocrystals as well as one-dimensional nanorods by the combined use of small angel X-ray scattering (SAXS), transmission electron microscopy (TEM) along with other physical techniques. The study includes growth kinetics of gold nanocrystals formed by the reduction of $HAuCl_4$ by tetrakis(hydroxymethyl) phosphonium chloride in aqueous solution, of CdSe nanocrystals formed by the reaction of cadmium stearate and selenium under solvothermal conditions, and of ZnO nanorods formed by the reaction of zinc acetate with sodium hydroxide under solvothermal conditions in the absence and presence of capping agents. The growth of gold nanocrystals does not follow the diffusion-limited Ostwald ripening, and instead follows a Sigmoidal rate curve. The heat change associated with the growth determined by isothermal titration calorimetry is about $10 kcal.mol^{-1}$ per 1 nm increase in the diameter of the nanocrystals. In the case of CdSe nanocrystals also, the growth mechanism deviates from diffusion-limited growth and follows a combined model containing both diffusion and surface reaction terms. Our study of the growth kinetics of uncapped and poly(vinyl pyrollidone) (PVP)-capped ZnO nanorods has yielded interesting insights. We observe small nanocrystals next to the ZnO nanorods after a lapse of time in addition to periodic focusing and defocusing of the width of the length distribution. These observations lend support to the diffusion-limited growth model for the growth of uncapped ZnO nanorods. Accordingly, the time ependence on the length of uncapped nanorods follows the $L^3$ law as required for diffusion-limited Ostwald ripening. The PVP-capped nanorods, however, show a time dependence, which is best described by a combination of diffusion $(L^3)$ and surface reaction $(L^2)$ terms

DNA barcoding of rotifers along the Cochin backwaters, southwest coast of India

This study examines the DNA barcoding of rotifers from the Cochin backwaters, Kerala, India, with specimens obtained from the pure culture, using primers LCO1490/ HCO2198 and a recently reported primer 30F/885R which was designed especially for the rotifers. Partial sequences of the mitochondrial COI gene from five species belonging to three genera (Brachionus, Keratella and Asplanchna) and two families (Brachionidae and Asplanchnidae) of the order Ploimida were generated. All the obtained nucleotide sequences were submitted to NCBI (accession numbers: OL477582–OL477584, OL477586 and OL757796)

Effect of curcumin and Cu<SUP>2+</SUP>/Zn<SUP>2+</SUP> ions on the fibrillar aggregates formed by the amyloid peptide and other peptides at the organic-aqueous interface

Characteristic features of a perilous neuro-degenerative disease such as the Alzhiemer's disease is fibrillar plaque formation by the amyloid (A&#946;) peptide. We have modelled the formation and disintegration of fibrils by studying the aggregate structures formed by A&#946; structural motif diphenylalanine as well as insulin and bovine serum albumin at the organic-aqueous interface. Even small concentrations of curcumin in the organic medium or Cu<SUP>2+</SUP> and Zn<SUP>2+</SUP> ions in the aqueous medium are found to break down the fibrillar structures

Surface-enhanced Raman scattering of molecules adsorbed on nanocrystalline Au and Ag films formed at the organic-aqueous interface

Surface-enhanced Raman scattering (SERS) of pyridine adsorbed on ultrathin nanocrystalline Au and Ag films generated at the liquid-liquid interface has been investigated. The shifts and intensification of bands formed with these films comprising metal nanoparticles are comparable to those found with other types of Au and Ag substrates. SERS of rhodamine 6G adsorbed on Ag films has also been studied. The results demonstrate that nanocrystalline metal films prepared by the simple method involving the organic-aqueous interface can be used effectively for SERS investigations

Selectivity in the Interaction of Electron Donor and Acceptor Molecules with Graphene and Single-Walled Carbon Nanotubes

Interaction of electron donor and acceptor molecules with graphene samples prepared by different methods as well as with single-walled carbon nanotubes (SWNTs) has been investigated by isothermal titration calorimetry (ITC). The ITC interaction energies of the graphene samples and SWNTs with electron acceptor molecules are higher than those with electron donor molecules. Thus, tetracyanoethylene (TCNE) shows the highest interaction energy with both graphene and SWNTs. The interaction energy with acceptor molecules varies with the electron affinity as well as with the charge-transfer transition energy for different aromatics. Metallic SWNTs interact reversibly with electron acceptor molecules, resulting in the opening of a gap

Surface-enhanced Raman scattering of molecules adsorbed on nanocrystalline Au and Ag films formed at the organic-aqueous interface

Surface-enhanced Raman scattering (SERS) of pyridine adsorbed on ultrathin nanocrystalline Au and Ag films generated at the liquid-liquid interface has been investigated. The shifts and intensification of bands formed with these films comprising metal nanoparticles are comparable to those found with other types of Au and Ag substrates. SERS of rhodamine 6G adsorbed on Ag films has also been studied. The results demonstrate that nanocrystalline metal films prepared by the simple method involving the organic-aqueous interface can be used effectively for SERS investigations

Solvothermal synthesis of nanorods of ZnO, N-doped ZnO and CdO

ZnO nanorods with diameters in the 80–800 nm range are readily synthesized by the reaction of zinc acetate, ethanol and ethylenediamine under solvothermal conditions. The best products are obtained at 330°C with a slow heating rate. Addition of the surfactant Triton®-X 100 gave nanorods of uniform (300 nm) diameter. By adding a small amount of liquid NH3 to the reaction mixture, N-doped ZnO nanorods, with distinct spectroscopic features are obtained. CdO nanorods of 80 nm diameter have been prepared under solvothermal conditions using a mixture of cadmium cupferronate, ethylenediamine and ethanol at 330°C. Similarly, Zn1−xCdxO nanorods of a 70 nm diameter are obtained under solvothermal conditions starting with a mixture of zinc acetate, cadmium cupferronate, ethanol and ethylenediamine