67 research outputs found
Magnetic and humidity sensing properties of nanostructured Cu[x]Co[1-x]Fe2O4 synthesized by auto combustion technique
Magnetic nanomaterials (23-43 nm) of CuCoFeO\ (x = 0.0,
0.5 and 1.0) were synthesized by auto combustion method. The crystallite sizes
of these materials were calculated from X-ray diffraction peaks. The band
observed in Fourier transform infrared spectrum near 575 cm in these
samples confirm the presence of ferrite phase. Conductivity measurement shows
the thermal hysteresis and demonstrates the knee points at 475C, 525C
and 500C for copper ferrite, cobalt ferrite and copper-cobalt mixed ferrite
respectively. The hystersis M-H loops for these materials were traced using the
Vibrating Sample Magnetometer (VSM) and indicate a significant increase in the
saturation magnetization (M) and remanence (M) due to the substitution
of Cu ions in cobalt ferrite, while the intrinsic coercivity (H) was
decreasing. Among these ferrites, copper ferrite exhibits highest sensitivity
for humidity.Comment: 12 pages, 7 figure
Preparation of Zinc-Sulfide Thin Films in the Presence of Sodium Tartrate as a complexing agent
The article offers information on the experiment done for the electrodeposition of zinc-sulfide (ZnS) thin films on the titanium substrate in the presence of sodium tartrate as a complexing agent. It states that the electrodeposition process has several advantages such as the possibility for large-scale production and minimum waste of components. It mentions that depositions were carried out by varying the deposition potential to determine the optimal conditions of deposition of ZnS thin film
Secondary crystalline phases identification in Cu2ZnSnSe4 thin films: contributions from Raman scattering and photoluminescence
In this work, we present the Raman peak
positions of the quaternary pure selenide compound
Cu2ZnSnSe4 (CZTSe) and related secondary phases that
were grown and studied under the same conditions. A vast
discussion about the position of the X-ray diffraction
(XRD) reflections of these compounds is presented. It is
known that by using XRD only, CZTSe can be identified
but nothing can be said about the presence of some secondary
phases. Thin films of CZTSe, Cu2SnSe3, ZnSe,
SnSe, SnSe2, MoSe2 and a-Se were grown, which allowed
their investigation by Raman spectroscopy (RS). Here we
present all the Raman spectra of these phases and discuss
the similarities with the spectra of CZTSe. The effective
analysis depth for the common back-scattering geometry
commonly used in RS measurements, as well as the laser penetration depth for photoluminescence (PL) were estimated
for different wavelength values. The observed
asymmetric PL band on a CZTSe film is compatible with
the presence of CZTSe single-phase and is discussed in the
scope of the fluctuating potentials’ model. The estimated
bandgap energy is close to the values obtained from
absorption measurements. In general, the phase identification
of CZTSe benefits from the contributions of RS and
PL along with the XRD discussion.info:eu-repo/semantics/publishedVersio
Effect of exposure to electron beam irradiation in biopolymer papain and their electrical behaviour
33-38The obtention of
biopolymer papain irradiated with 8 MeV energy of electron beam to different
doses from 1 kGy to
10 kGy and the effect of the radiation on the electrical behaviour of the
biopolymer have been investigated in the temperature range 29°-135<span style="font-family:Symbol;mso-ascii-font-family:
" times="" new="" roman";mso-hansi-font-family:"times="" roman";mso-char-type:symbol;="" mso-symbol-font-family:symbol"="" lang="EN-GB">°C. The <i style="mso-bidi-font-style:
normal">ac impedance plots indicate a single relaxation process in
biopolymer papain in different temperatures. An increase in bulk electrical
conductivity was noted for biopolymer papain with temperature after irradiation
which is related to the hopping of charge carriers between the sites. The
electrical conductivity of fresh and irradiated papain follows the universal
power law and from which it is observed that the <i style="mso-bidi-font-style:
normal">ac conductivity is frequency dependent and it obeys the electron
tunneling model of conduction mechanism. The SEM images reveal the larger
particle size with non-uniform structure upon irradiation of papain.
</span
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