Amount Of Organic Additives Research Articles

Controllable Synthesis of CaMoO4 Microcrystals with Tailored Morphologies and Optical Properties

CaMoO4 microcrystals with controllable morphologies and luminescent properties were successfully synthesized via hydrothermal treatment. The as-prepared samples are characterized using X-ray powder diffraction, scanning electron microscopy; Fourier transformed infrared spectra. By adjusting the fundamental experimental parameters including reaction time, temperature and the amount of organic additives, CaMoO4 exhibited various morphologies, such as particles, dumbbells as well as flowers. Moreover, it is seen that CaMoO4 can be well crystallized with tetragonal structure at room temperature. The photoluminescence spectra of CaMoO4 display a strong and broad band emission with a maximum at 550 nm under excitation wavelength of 310 nm at room temperature. The luminescent intensity of CaMoO4 varied with the reaction time and temperature and was optimized at 200 oC, 45 h. The work provides a facile synthetic route for the construction of inorganic materials with controllable morphologies and luminescent properties

Optimization of the parameters for nickel electrowinning using interference microscopy and digital image analysis

Ni electrodeposition experiments at a constant current density 220 A/m2 were performed to determine the optimum concentrations of chloride and an organic additive used for an industrial Ni electrowinning. White light interference microscopy was used to acquire digital images of the morphology of the electrodeposited nickel. The scaling analysis was employed to parameterize the morphological information encoded in the images. The standard deviation of the surface height, δ, the critical scaling length, L c, and the optical roughness, 4δ/L c, were determined as a function of the chloride concentration and the amount of organic additives. These parameters were plotted as a function of the two compositional variables. These three-dimensional plots allowed us to find conditions corresponding to the minimum of 4δ/L c, at which the deposited nickel is well leveled.

Application of atomic force microscopy and scaling analysis of images to predict the effect of current density, temperature and leveling agent on the morphology of electrolytically produced copper

Atomic force microscopy (AFM) was used to study the morphology of electrodeposited Cu at current densities from 183 to 253 A m −2. Digital image analysis was employed to parameterize the morphological information encoded in AFM images and to extract information concerning the mechanism of the electrodeposition reaction. It has been shown how the limiting roughness, δ, the critical scaling length, L c and the aspect ratio, 4 δ/ L c, vary as a function of the deposition time and electrodeposition conditions, such as temperature, current density and the amount of organic additives. It has been demonstrated how laboratory experiments of short duration and the scaling analysis of AFM images can be used to predict roughness of the metal sample after 2 weeks of industrial electrorefining.

X-Ray Diffraction Investigation of Electrochemically Deposited Copper

Copper layers were deposited from acidic electrolytes containing different amounts of organic additives, designed for the formation of Cu-interconnect structures. Amorphous Ni-P substrates allow to study the unbiased growth of the electrodeposits. The crystallographic texture was investigated by the determination of X-ray diffraction (XRD) pole figures and the calculation of the orientation distribution functions. XRD results are discussed in relation to the morphologies of the electrodeposits as investigated with light optical microscopy and correlated with the process parameters during electrodeposition.

Whisker alignment by slip extrusion

Si 3N 4 or Al 2O 3 ceramic slips containing 20–30 vol.% SiC whiskers and small quantities of a dispersant and gelling agent were prepared by ultrasonic dispersion and ball milling. The viscosity was minimized by adjusting the pH of the slip and the amount of organic additives. The slip was extruded into a gelling solution through a hypodermic syringe fitted with a 0.5 mm internal diameter stainless steel needle. The conversion of the extruded slip into a flexible thread was accomplished by an ion exchange reaction in the gelling solution. The orientation of the whiskers in the extruded thread was determined by infiltrating an epoxy resin into the dried thread and measuring the distribution of the angle between the whiskers visible on a polished cross-section and the extrusion direction. The degree of whisker alignment in the thread was defined in terms of a statistical orientation factor 0 which varied from 0 to 1 as the whisker distribution changed from randomly oriented to complete alignment in the extrusion direction. Optimum whisker alignment was achieved at large needle length-to-diameter ratios, low slip viscosities and high extrusion velocities.