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Heavy metals ions are ions which generally occupied most part water sources such river, sea and other water flow channels such as drainage, water pipe. The exist of the ions in drinking water traces have called the attention researchers due to the recent discovery of the ions problem in both human health and aquatic animal such as fish. Fish come and encounter heavy metals ions in the river and ingest it and subsequently this fish eaten by man. The ions will pass to human and attack some human orgains. Finding the reliable solution to detect traces of heavy metals ions in water is a promising approach to eliminate such problems. This research aim is to enhance detection of heavy sensors, for sensor technology industry using the fabricated MTES surface-modified silicon interdigitated electrode to detect arsenic ion in water, The device was fabricated using conventional photolithography process coupled with deep RIE etching. The fabricated devices was modified surface and characterized by Scanning Electron Microscopy, Atomic Force Microscopy and high-power microscopy. The electrical analysis by applying voltage to measure the device response to the surface modification step and subsequently against arsenic ion as it bonded to the device via MPTES, various MTES concentrations distinguished against the bare device and arsenic concentration. Based on current and voltage analysis, concentration-dependent results were obtained, the detection limit for surface modified IDE to the arsenic detection was 20 pM with the linear response behaviour to the concentration, Thus, with this wonderful detection limits, the devices high high-performance characteristic by selectively distinguish arsenic ions against other foreign elements in the water.

The paper presents modeling by classical molecular dynamics of second order elastic constants of NaCl (B1 rocksalt structure) at high pressures. The Born-Mayer-Huggins-Fumi-Tosi potential and Coulomb potential were used to simulation interaction of ions of sodium chloride. The results demonstrate that under normal conditions the distributions of the elastic moduli, shear moduli, and Poisson's ratios for classical molecular dynamics are isotropic, in contrast to the distributions obtained by the experiment and the density-functional-theory. The elastic isotropy of NaCl under normal conditions for classical atomistic simulation also indicated by Zener anisotropy ratio, which is approximately equal to 1. At high pressures, the elastic anisotropy of sodium chloride appeared and a Zener anisotropy ratio is in good agreement with the experiment and the density-functional-theory calculation.

Two types of thermally unstable U1 centers are created in LiF:Mg,OH crystals by γ−irradiation at low temperatures. One of them is influenced by impurity complexes containing magnesium ions Mg2+. Another type of U1 center is perturbed by impurities of OH¯ ions. Temporal dynamics of conversion of U1 centers and F2+ and F2+** color centers after crystal was heated from temperature of 80 K to 300 K is presented.

Platinum nanoparticle electrode modified by iodine monolayer (PtNPs/I) has been designed to simultaneously determination of Pb2+ using square wave voltammetry (SWV), the analyzed the anodic peak current and anodic maximum potential is done. The scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) demonstrate some fascinating characteristics of the uniform particle distribution, growth and self-assembly of the iodine-modified platinum nanoparticle. The also examined the effect of the concentration of lead and the effect of the scan rate on anodic top parameters. The results show that the anodic current peak increases and that the anodic peak potentials increase in comparison to the clean electrode to a negative value. The have noticed that lead and scan rate increases, anodic peak current increases. As the lead concentration and scan rate increase, the anodic peak potential changes to more positive values. The easily reproducible RSD 5% (n=5) removal peak current for heavy metal ion was shown under ideal conditions. For a pre-concentration time of 120 s, the linear ranges are between 1 to 100µg. L−1. For lead ions, the concentration limit was measured as 0.408 µg. L-1 using the improved analytical process. The transmitter was a lead ion with a 0.215 µA/µM-cm2 range, with a measurement maximum of 0.01 µM.

The optical spectra of BaBrI crystals activated by divalent samarium were studied. The samples exhibit bright luminescence in the red region of spectra due to 4f6–4f6 and 4f55d1–4f6 transitions of Sm2+ ions. Luminescence exhibits strong temperature dependence in the range 7–300 K. At low temperatures, luminescence associated with parity-forbidden 4f6–46f transitions from 5D0 and 5D1 states is observed. Coloring of the crystals after irradiation by ultraviolet light and long afterglow luminescence of BaBrI:Sm2+ were detected.

The study presented a functionalized silicon with (3-aminopropyl) triethoxysilane (APTES) to serve as a sensor for heavy metal detection. The amino-functionalized Si nanowires were tested against the heavy metal, lead (Pb). Due to the silicon electrochemical response towards the heavy metal ions, linear response to four different sources of water was observed. The results indicated that Pb can be detected with a high precision. Furthermore, confirmation was demonstrated using atomic absorption spectroscopy to determine the level lead content in the collected water source. Tab water (H2O), River H2O, Treated (H2O), DI (deionized) H2O and found the levels of 0.0859 mg/L, 0.0929 mg/L, 0.0052mg/L, 0.0023 mg/L with 5.8pA, 7.2pA, 4.6pA, 3.3pA current responses, respectively. Thus, with this high capability to discriminate water samples, the sensor potential can be employed for effective heavy metal detections and further be extended to a large sensor network in water treatment plant. A new microfluidic bonding material based on SU8 to implement electrical Nano chemical sensors for ions sensing, and an investigation of direct electrical measurement allowed for label free detection.. Thus, the study developed new room temperature bonding method using SU8 as an intermediate adhesive layer. The SU8 modified bonding was compared with non modified. The bond strength of SU8 modified was found to be stronger than ordinary plasma bonding under the same curing conditions. Overnight room temperature curing yields an average burst pressure of 420 kPa, which is more than adequate for many PDMS sensor devices. In contrast, non SU8 coated plasma bonded resulted in a burst pressure of only 174 KPa.

Characteristics of LiF crystals irradiated by pulsed laser radiation with pulse duration of 50 fs, an energy of about 5 mJ, and a wavelength of 950 nm were studied. After single-pulse irradiation, a band with maximum at wavelength of 450 nm related to formation of F3 color centers was observed in the extinction spectra of sample. With an increase in the number of pulses, components associated with more complex aggregate F3 (R), F3, and F4 (N) centers appear in the band structure. The observed association of F3+ centers leads to the formation of larger aggregates up to the precipitation of nanoscale lithium clusters, which is confirmed by comparison of spectra of the crystals irradiated with laser pulses and the crystals irradiated with high-energy Li+ ions with use of ion implanter. Atomic force microscopy study confirmed the conclusion that lithium nanoparticles with sizes in the range of 60–90 nm were formed in surface layer of LiF crystal as a result of laser irradiation.

The dielectric spectra of LaF3 crystals activated by rare-earth ions Eu2+, Sm2+, and Yb2+, gradually cooled from 300 to 240 K, were investigated. Obtained experimental data were compared with experimental data obtained previously by other authors. The reorientation activation energies for RE2+ dipoles in LaF3 are 0.49, 0.55, 0.56, and 0.58 eV for Ba2+, Sm2+, Eu2+, and Yb2+, respectively. A reorientation of fluorine vacancy is observed, across the F1 positions.

The modeling of X-ray spectra from photoionized astrophysical plasmas has been significantly improved due to recent advancements in the theoretical and numerical frameworks, as well as a consolidated and reliable atomic database of inner-shell transitions for all the relevant ions. We discuss these developments and the current state of X-ray spectral modeling in the context of oxygen cold absorption in the interstellar medium (ISM). Unconventionally, we use high-resolution astrophysical observations to accurately determine line positions, and adjust the theoretical models for a comprehensive interpretation of the observed X-ray spectra. This approach has brought to light standing discrepancies in the neutral oxygen absorption-line positions determined from observations and laboratory measurements. We give an overview of our current efforts to devise a definitive model of oxygen photoabsorption that can help to resolve the existing controversy regarding ISM atomic and molecular fractions.

Solution combustion method at altered temperature was employed for the synthesis of undoped and Sm3+ doped MgAl2O4 phosphor. X-ray diffraction (XRD), photoluminescence (PL) spectroscopy and UV-Vis spectroscopic techniques were used for the characterization of phosphor. XRD results confirmed that the phosphor synthesized at 600 °C was in a single phase and belong to the cubic structure of the MgAl2O4. Under 410 nm excitation, the phosphor exhibits emission peaks centered at 574 nm, 616 nm, 659 nm and 693 nm, resulting from 4G5/2 − 6HI/2 (I= 5, 7, 9, 11) transitions of Sm3+ ion, respectively. The optimum molar concentration of Sm3+ was 3 mol. %. The band gap of phosphor was calculated from the diffused reflectance spectrum and it was found to be ∼5.1 eV.

Pure and magnesium modified SnO2 nanoparticles synthesized by using sol-gel method were studied for enhancement in emission properties. Pure and Mg modified SnO2 nanoparticles were analyzed by using X-ray Diffractometer (XRD), Photoluminescence spectra (PL) and Scanning Electron Microscope (SEM). From the XRD analysis, the average crystallite size was found to decrease from 14 nm to 10 nm with the insertion of Mg2+ ions in SnO2 matrix. Agglomeration due to interaction of nanoparticles with the doping has been studied by using SEM analysis. Photoluminescence measurements performed at room temperature show peak in UV region as well as visible region. A significant increase in the PL intensity with the doping was observed in both the regions which might be due to presence of oxygen vacancies as surface defects.

The (La1-xPbx)MnO3where x = 0.3-0.5 solid solutions were prepared using solid state reaction route. The X-ray diffraction (XRD) data reveals the single phase formation. The microstructures shows that grain size as well compactness of grains increases with increasing Pb2+ content. However density of the samples also increases with incraesing x. The magnetic data shows the ferromagnetic behavoir of the solid solutions as x increases from 0.3 to 0.5.

Alkali alkaline earth borate glasses with composition (in mol %) of 25Li2O-15BaO-(60-x) B2O3-xFe2O3 (0 ≤ x ≤ 1) (LBBF) were prepared by conventional melt quenching method. The structural properties of glass samples were studied using infrared (IR) and Raman spectroscopic techniques. The IR studies show different stretching and bending vibrations of alkali alkaline earth borate glasses. It was also observed that the fraction of four-coordinated boron atoms, N4, decreases with increasing the concentration of Fe2O3 up to 0.8 mol%. This is due to the structural changes involving the conversions of the BO4 in to BO3 structural units as the concentration of the Fe2O3 glass modifier increases up to 0.8 mol%. Therefore for the studied glasses the BO4 units will be destroyed and converted in to BO3 and BO2Ō units with NBOs. Raman spectra confirm the IR results regarding the presence of iron ions mainly as FeO4 and FeO6 groups. The network modifications were due to the creation of NBOs by increasing iron ions concentration. Thus the addition of Fe2O3 into the LBBF glass indicates that it acts as glass modifier and takes part in network formation.

In this paper Ce-Mg binary oxide nanoparticles were synthesized by simple co-precipitation method at room temperature for removal of lead from aqueous solution. The prepared material was characterized by XRD and TGA/DTA. Batch experiments was carried out to study the effects of the important parameters such as contact time, initial concentration of lead, dosage of nanoadsorbent and pH of the solution on the adsorption of lead by Ce-Mg binary oxide nanoparticles. The maximum removal of lead (II) is found to be 60 % at optimum pH of 5.5 at initial Pb (II) concentration of 10ppm and an adsorbent dosage of 1g/L. Dynamics of adsorption process was analyzed by applying different kinetic and thermodynamic models. The results showed that kinetics data for adsorption of lead ions shows better fit with pseudo second order model whereas the thermodynamics data showed a good fit with the Freundlich isotherm. This study indicates that Ce-Mg nanoparticles as an adsorbent for the removal of Pb (II) in water treatment.

Pr3+-doped borate glasses of the composition 10PbO - 20Na2O -10MO - 60B2O3-XPr2O3 with M= Ba, Sr, Ca, and X= 0, 0.1,0.3,0.5 mol% were prepared by melt-quenching method. UV–Vis absorption measurements were made to examine the influence of Pr3+ concentration on optical properties. From the absorption edge data, indirect, direct band gap and urbach energy is calculated and tabulated. Energy band gap and Urbach energy detailed studied made to know the changes due to the incorporation of different alkaline earth metal ions

In this work, we demonstrate an optical fibre tip sensor coated with chitosan for lead ion (Pb2+) detection. The sensor was fabricated using a tip of standard single mode optical fibre. The fibre tip region was cleaved and dipped into chitosan solution to form a sensitive layer. The coated sensor was exposed to different Pb2+ concentration ranging from 0 to 70 ppm. In order to compare the sensor’s performance, the uncoated optical fibre tip sensor was firstly used to perform the measurement. The chitosan-coated tip sensor has greatly enhanced the sensor’s sensitivity 7 times higher compared to uncoated the sensor with high linearity up to 97%. As the proposed sensor shows a promising potential in detecting Pb2+, we believe the application of the sensor can be extended for environmental and wastewater monitoring.

When the bulky ions encounter at elevated relativistic energies, the entire system undergoes variant changeover phases, starting with nuclei picture up to hadronic phase via intermediating plasmonic phase composed of quarks and gluons. In view of the fact that this created matter is believed to possess strong coupling and thus it is not idealistically feasible to take up pQCD theory merely to figure out the bulky medium’s distension. Here we look for some approaches to figure out the plasma creation phenomena theoretically, when it faces changeover through various stages.

100 keV silicon negative ions implanted SiO2 thin films with fluences varying from 1 x 10 15 to 2 x 10 17 ion cm−2 were investigated using Electron spin resonance (ESR) at low temperature and Energy dispersive X-ray spectroscopy (EDX) techniques. ESR studies showed the presence of oxygen vacancies related to silicon dangling bonds (Pb-centres) at g-values ranging between 2.0034 to 2.0038. The ESR signal intensity was found to increase with decrease in the temperatures from 223K to 123K. The defect density estimated from ESR signal was found to increase from 1.9 x 1016 cm-2 to 3.5 x 1016 cm-2 with decrease in the temperature from 223K to123K. EDX studies revealed the decrease in the atomic percentage ratio of oxygen to silicon with respect to increase in the silicon ion fluences in SiO2 thin film layer. EDX results showed the increase in Si-Si bonds formed as compared to Si-O bonds due to breakdown of SiO2 lattice after implantation.

In this study, we investigated the possibility of the synthesis of Na-zeolite A from Bangka kaolin and examined its ability to removal of Fe3+, Pb2+, and Cu2+ ions from aqueous solutions. Na-zeolite A was prepared from Bangka kaolin by hydrothermal treatment. The adsorption experimental was conducted in batch method. SEM observation of Na-zeolite A indicated crystal morphology, which is characterized by cubic shaped crystals. The contact time for adsorption capability was varied from 0 to 90 minutes. Atomic absorption spectroscopy (AAS) is used to determine the adsorption efficiency. The results showed the removal efficiencies of Fe3+, Cu2+ and Pb2+ ions using Na-zeolite A in aqueous solution are 90.19, 44.17 and 35.24%, respectively. These properties showed that Na-zeolite A is suitable as adsorbent for removal of heavy metal ions from wastewater.

In this work, we present the computation of fragmentation cross-section of 28Si ion beam projectile incident on 12C target of depth 1.31 g/cm2. The Monte Carlo (MC) code-based toolkit Geant4 written in C++ language is used for the simulation study. Three different models of physics, the Quantum Molecular Dynamics (QMD), the Leige Intranuclear cascade (INCL), and the Binary Cascade Model (BIC) models are activated separately in the Geant4 PhysicsList class. The computational results are comparatively analyzed with respect to experimental data. The fragmentation cross-section of Si ion for incident energies 266 A MeV, 344 A MeV, 560 A MeV, 765 A MeV, and 1147 A MeV is computed. These models regenerate experimental results of projectile fragmentation cross-section with good agreement taking acceptance angle of experimental technique into consideration.

In the present work structural and dielectric investigations are carried out in magnesium ferrite/molybdenum trioxide (MFMO) [MgFe2O4−MoO3 with 0.5:0.5 mass ratios] synthesized by mechano-chemical synthesis. Magnesium Ferrite and the MFMO are structurally characterized by XRD and SEM techniques. In the XRD pattern of the composite shows appearance of peaks MoO3 along with that of MF thus confirms the formation of the composite. The MFMO shows crystalline nature with an average crystallite size of 12 nm. From SEM of images of MFMO, it is evident that the substitution of MoO3 affects the microstructure of MF. The Alternating Current (AC) response parameters of MF and the MFMO were comparatively studied in the frequency range 102-105 Hz at room temperature. Decrease in AC conductivity and Dielectric constant of the MFMO was observed. Decrease in AC conductivity is attributed to blockade of path by Mo ions in the B-sites. Hence these properties suggest the possible use of these ferrites in high frequency and microwave devices applications.

Silica glasses doped with different concentrations of Tb3+ and Al were prepared by sol-gel method. The prepared glass samples were annealed at 1020°C to remove residual hydroxyl groups. The effect of Al on the optical properties was studied from the luminescence spectra of the prepared samples with 254nm excitation. 5D3 emission peaks were observed at 378nm, 414nm, 440nm and 460nm resulting from the transitions 5D3 → 7F6, 7F5, 7F4 and 7F3 respectively. 5D4 emission peaks were also observed at 488nm, 543nm, 588nm and 624nm resulting from the transitions 5D4 → 7F6, 7F5, 7F4 and 7F3 respectively. The 5D3 emissions were found to be greatly enhanced in the presence of Al. Differences in the shapes, positions and relative intensities of the 5D4 emission lines were also observed between Tb3+ doped and Tb-Al co-doped samples indicating the modification of the local Tb3+ environment in the presence of Al. The observations are in support of the reduction in energy transfer and cross-relaxation processes as well as higher diversity in the Tb3+ ion site in the presence of Al.

A tritium (T) campaign is planned in preparation for the deuterium-tritium (D-T) campaign at the Joint European Torus (JET). These experiments will be the first experiments involving T with the ITER-like plasma-wall facing components materials. They will give a unique opportunity to test one of the most promising ion cyclotron resonance frequency (ICRF) heating schemes for ITER plasmas: the 2nd tritium (T) harmonic resonance (ω = 2ωT). This paper provides two key contributions related to modelling of the performance of this scheme at JET. First, we assess the heating performance of the 2nd T harmonic resonance and, second, we model different ICRF schemes for the T campaign in support for the D-T campaign, i.e., identify differences and similarities from the heating point of view between T and D-T plasmas in order to predict the performance of ω = 2ωT in the D-T scenario. In our modelling we use a selected hybrid record discharge as reference, i.e., using its experimental profiles. We consider two ICRF schemes (6 MW), i.e. ω = ω3He = 2ωT (no 3He), with a central resonance and three NBI power outputs (15, 25 and 35 MW) in two plasma compositions ( 100% T and 50%:50% D-T). Note that isotope effects are not taken into account in these simulations. For this study, the ICRF and NBI heating are modelled with the ICRF code PION and the beam code PENCIL which take into account the ICRF+NBI synergy. The analysis of the T velocity distribution function shows that a stronger tail is formed in those plasmas with lower tritium density. This fact has an important impact on the slowing-down process of fast tritons with the background species. The T plasma shows a higher and more peaked ion-ion collisional power density at the plasma centre as compared to D-T plasma. In the T plasma, ICRF heating drives fast tritons at the plasma centre with an average energy substantially lower than in the other case. On the other hand, the use of 3He as a minority makes the fast ion T energy considerably lower due to strong 3He absorption. Fast ion average energies reached at the plasma centre are similar in all species mixture cases. As a result, there is a strong heating similarity between T and D-T. However, it is crucial to study the generation of a strong T tail as a result of particle-wave interaction which is not possible under this scheme and needs to be studied in plasmas without 3He in preparation of JET D-T campaign and ITER. Therefore, both schemes (ω = ω3He = 2ωT and ω=2ωT) need to be tested.

Influence of Dy3+ ion on physical and absorption studies of zirconium based alkali borate glasses have been prepared using muffle furnace by conventional melt quench method. Samples were analyzed using certain measurements like XRD and UV-Vis. Physical parameters like density, molar volume were calculated. XRD spectra confirm the amorphous nature of all samples as there is no sharp peaks. Uv-Visible absorption studies were carried out and by utilizing Tauc’s equation direct and indirect band gap, Urbach energy was estimated. Energy band gap values are tabulated and discussed in detail for the better understanding.

A molecular dynamics simulation of small PuO2 nanocrystals consisting of 105−174 ions at the temperature T = 1700 K was carried out. The structures of the vertices and the surface created during thermal disordering and subsequent relaxation of these nanocrystals were studied. The vertices formed by two adjacent plutonium cations, as well as truncated vertices of the regular octahedron that consisted of 4 plutonium cations lying in the same plane (100), were most frequently encountered. Sharp vertices of the regular octahedron ending in one cation usually corresponded to metastable states of the crystal lattice or to crystallites with an increased specific energy. According to the results, sequences of the “magic numbers” were proposed to specify the sizes of plutonium dioxide nanocrystals characterized by the most stable surface.

In order to understand the dependability of the crystal structure and the magnetic properties of the nanoparticles as adsorbent of Pb ions, magnesium ferrite (MgFe2O4) based on natural iron sand with various concentrations of ammonia solutions (0.5, 1, 1.5 and 2 M) have been synthesized using a co-precipitation method. X-ray diffraction analysis revealed that MgFe2O4 formed a single phase, in which the size of the crystal decreased by increasing the ammonia concentrations. The smallest crystal size was obtained at 2 M of NH4OH addition. On the other hand, the VSM analysis showed that the magnetization saturation (Ms) increased by increasing the ammonia concentration, while the coercivity decreased. The highest value of Ms was achieved at 48.2 emu/g by adding 2 M of NH4OH. This result affected the ability of the nanoparticles to adsorb Pb ions. The large surface area due to small particles size and its high saturation can adsorb Pb ions up to 92.65 mg/g, with an efficiency of 84.23%. Therefore, these nanoparticles have a potential application to be used as heavy metal adsorbent in waste-water.

Single crystals of Ca2+ (CCoCO) and Mg2+ (MCoCO) doped cobalt cadmium oxalate were grown by single diffusion method in silica hydro gel at room temperature. Optimum conditions of the as grown crystals were established by varying Specific gravity of Sodium Meta Silicate (SMS), gel setting time, pH of the gel, concentrations of Oxalic acid and concentration of Ca2+ and Mg2+ solutions. Energy dispersive X-ray analysis (EDX) confirmed the presence of major elements such as Co2+, Ca2+, Mg2+, Cd2+ ions in the lattice of the grown crystals. Fourier transform infrared (FT-IR) spectrum exhibits the presence of OH, carboxyl group and metal-oxygen bonding. UV-Visible spectroscopic analysis measured the energy gap and insulating behavior of the crystals.

In this paper, we report the Ca2+ and Mg2+ cation exchange activities of the synthesized Na-zeolite A, which was synthesized from Indonesian Bangka kaolin by hydrothermal method. The application of activated Na-zeolite A as water softener was studied. The objective of this research is to observe the activated Na-zeolite A as a water softening agent to remove simultaneously the Ca2+ and Mg2+ ions from water solution. In principle, activated zeolite-A can be used as a water softener using the ion exchange concept. Atomic absorption spectroscopy (AAS) technique was applied for quantitative analysis of the remaining cations content in water samples after treatment with activated Na-zeolite A as adsorbent for the removal of Ca2+ and Mg2+ ions. The adsorbent dosage of activated Na-zeolite A was varied in the range between 30 mg to 2 g and also the contact times were varied from 0 to 90 min. The highest removal efficiency of Ca2+ (95.97%) and Mg2+ (94.93%) from hard water were Na-zeolite A as adsorbent for Ca2+ and Mg2+ removal from water. These properties of the activated Na-zeolite A suggested that it is suitable and effectively used in hard water softening and detergent building for Ca2+ and Mg2+ removing.

A sequence of Dy3+ ions activated LiSrBO3 phosphors were developed using solid state reaction. The obtained samples were studied by X-ray diffraction and FESEM for their structural evaluations. The broad diffraction lines intimated the nanocrystalline nature of the prepared phosphor. The photoluminescence excitation spectrum showed several narrow excitation bands ranging from 280 nm to 400 nm. The UV irradiated emission spectra indicated that LiSrBO3: Dy3+ can be effectively excited by near UV light by generating two prominent emissions in blue and yellow region which are attributed to the 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions of Dy3+ ion. The investigated samples were found to be suitable for their application in white LEDs.

Multiferroic nanoparticles of Bi1-xDyxFeO3 (x=0 and 0.10) have been prepared by sol-gel method and the variation in their structural, morphological and magnetic properties has been studied. Structural analysis reveals distortion of rhombohedral lattice of BiFeO3 by the substitution of Dy3+ions. The shift observed in the diffraction peaks with Dy3+ ions indicates its successful substitution. The morphological analysis shows the formation of agglomerated nanoparticles having average particle size 25 and 18 nm for undoped and Dy-doped BiFeO3 nanoparticles, respectively. The observed agglomeration is due to high surface energy of synthesized nanoparticles. Magnetic studies confirm typical ferromagnetic behavior for the synthesized nanoparticles. Enhancement in saturation magnetization values with Dy-substitution is attributed to suppression of spin cycloid structure by the reduction in particle size, lattice distortion and surface induced magnetization.

This article briefly reviews and explores the various polarization mechanisms involved in ionic crystals in different conditions. Ionic polarization is a mechanism that contributes to the relative permittivity of a material. This type of polarization typically occurs in ionic crystal elements such as NaCl etc. There is no net polarization inside these materials in the absence of an external electric field because the dipole moments of the negative ions are cancelled out with the positive ions. However, when an external field is applied, the ions become displaced, which leads to an induced polarization. Ions bound together by electrostatic attraction form ionic crystals. Their arrangement varies depending on the ion’s sizes or the radius ratio (the ratio of the radii of the positive to the negative ion). A simple cubic crystal lattice has ions equally spaced in 3D at 90° angles. Stability of ionic solids depends on lattice energy, which is released in the form of heat when two ions are brought together to form a solid. Lattice energy is the sum of all the interactions within the crystal. The properties of ionic crystals reflect the strong interactions that exist between the ions. They are very poor conductors of electricity, have strong absorption of infrared radiation, and are easily cleaved.

In the present study a polymer nano composite has been prepared by using MWCNT and polymer salt complex. To understand the ion migration process of the mobile ions present in the system, Ac conductivity and dielectric data has been analyzed and fitted with different theoretical models. Frequency dependent ac conductivity spectra have been fitted with Joanscher’s power law equation. Conductivity master curve shows a temperature independent ion migration process. Further, permittivity data has been fitted with Havriliak Negami equation. Permittivity data shows an existence of near constant loss at high frequency. Thermal dependency of this phenomenon has further been examined. The relaxation parameter obtained from Havriliak Negami fitting indicates presence of slower relaxation process at sub ambient temperature. A similar conclusion has also been obtained from tan delta peaks.

Germinate- tellurite glasses of composition TeO2-Li2O-WO3-Ge2O-Yb2O3-Tm2O3-Ag2O (TWLGTYA) are synthesized by the melt-quenching method. In these glasses Ag nanoparticles (AgNPs) growth was controlled by reheating above the glass temperature. The absorption spectrum of the samples is measured for identification of the different absorption level of Tm3+ and Yb3+ ions. The intense blue band at 456nm emission of Tm3+ ions under 808nm excitation is investigated without AgNPs samplesTWLGTY7. For 0.7 mol% of Ag2O with 7hrs reheat-treated TWLGTYA samples is attributed to the enhanced 537nm emission corresponding to transition 1D2→ 3F4 due to the local field on the Tm3+ ions locations. It shows that due to presence of Ag NPs, significantly enhance the 537nm emission Tm3+ ions by surface plasmon resonance (SPR). Also incorporation of Yb3+ into TWLGTYA glass can effectively improve the blue 456 nm emission could be useful in the field of sensor materials.

The structural and optical properties of pure and TiO2 doped WO3 samples have been analyzed to study the modification of the electronic structure and disorder developed in the samples due to TiO2 doping. The samples are of single phase in nature and no secondary phase or any impurity peak has been detected from structural analysis. The incorporation of Ti ions introduces disorder in the system which leads to slight degradation in crystallinity of the samples with increasing doping. There is decrease in grain size with increase in TiO2 doping concentration. The band gap shows red shift with doping. This is due to the formation of impurity band and trapping of Ti atoms which leads to the generation of the defect states within the forbidden band. Photoluminescence (PL) spectra shows gradual decrease of intensity of blue emission peaks with increasing TiO2 doping. These structural and optical studies manifest increase in defect or disorder in the system with increasing TiO2 doping.

The presence of small amount of calcium in the solution of crystallization of struvite-K crystals was studied using the different spectroscopic techniques, like SEM, FTIR and EDAX. It was found that, calcium ions transform the morphology of struvite-K crystals. However in FT-IR spectroscopy, as compared to undoped some OH vibrations as well as the four fundamental modes of vibrations band ν1, ν3, ν2, and ν4 was also observed in the spectrum of Ca2+ doped sample, but these vibrations are slightly shifted. The observed changes in the vibrations were due to the influence of additive ions. EDAX techniques is use to determine the percentage composition of elements present in the doped crystals. It revealed that the sample was of a mixed composition.

In recent years negative ion implantation technology has established itself as a very good alternative technique to positive ion implantation, as it has the advantage of low surface charging voltage effect, which is one of the essential criteria in designing of large scale integrating devices. The present work describes the modification of structural and electrical properties of semi insulating GaAs sample implanted with 100 keV silicon negative ions with fluences varying from 5 x 1014 to 2 x 1016 ions cm−2. The Glancing angle X-ray diffraction study showed decrease in the intensity of GaAs (311) Bragg’s plane for implanted sample compared to un-implanted sample. The crystallite size calculated from FWHM and Debye – Scherrer formula was found to vary from 10.20 nm to 11.20 nm. The current-voltage measurements showed increase in the conductivity with respect to ion fluence for implanted samples.

Ion cyclotron resonance heating (ICRH) plays an important role in high performance JET-ILW plasma discharges, both for keeping the heavy impurities away from the plasma centre as for increasing the core ion temperature to boost fusion performance. While the former is needed in all high-performance discharges for steady state operation, the latter will be particularly important in the next-coming JET Deuterium-Tritium campaign (DTE2). Currently, the workhorse for impurity control in high power D plasmas is fundamental H minority ICRH (with simultaneous ω=2ωc harmonic D heating), which leads to localized core electron heating that induces turbulence (flatter density profiles) as well as peaked electron temperatures. For fusion power enhancement, dominant bulk ion heating and RF acceleration of the NBI ions to appropriate energies would be preferable and theoretical predictions suggest that ion heating is also effective for core impurity screening. In this paper, we discuss the basic modeling results of different ICRF scenarios available for the DTE2 campaign in JET-ILW, highlighting their main properties in terms of the RF absorption of the various species, their slowing-down properties and their impact on high-Z impurity transport. Correctly modeling the wave absorption, slowing-down and collisional energy redistribution of the simultaneously RF-heated species in a DT plasma mix with important neutral-beam injection (NBI) is numerically challenging and is outside the scope of this paper. The simplified calculations presented here are rather intended to give the reader an overview of the ICRH options for JET-DTE2 with references to the state-of-the-art ICRH modeling given throughout the paper.

The influence of ELMs on the propagation of fast wave in the ion cyclotron range of frequency is studied. The 3D edge turbulence code BOUT++ with the Six-field two-fluid model is used to calculate the perturbed density during ELMs, and the antenna code RAPLICASOL is then applied to calculate the antenna fields using the calculated 3D density. The results indicate that ELMs can cause an electric field perturbation in the range of 4.5% - 45% for an ELM induced density perturbation in the range of 3%-30%.