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The sol–gel auto-combustion process synthesized materials with Mg2+ and Ce3+-substituted CoFe2O4 nano ferrites. The research focuses on the nanoparticles, specifically Co1−xMgxFe2−yCeyO4 (where x = 0.0, 0.25, 0.5, and 0.75; y = 0.0, 0.03, 0.06, and 0.09) (CMC) ferrite nanomaterials characterizations utilizing techniques such as XRD, FESEM with EDS, FTIR, electrical analysis, and VSM. The X-ray powder diffraction (XRD) patterns indicate the formation of a spinel structure, with no distinct peaks for rare earth ions, likely due to their minimal doping. Increasing the ionic sizes of RE3+ ions decreases the lattice parameter of the resulting nanoferrites. Field emission scanning electron microscopy (FESEM) shows the samples are aggregated and nearly spherical. At the same time, energy-dispersive X-ray spectroscopy (EDS) confirms the presence of Co, Mg, Ce, Fe, and O. Fourier-transform infrared spectroscopy (FTIR) absorption bands predict the range of spinel ferrites, indicating that RE3+ ions replace Fe3+ ions in the B sites. DC electrical resistivity decreases with the concentration of substituted ions. Dielectric properties, including the dielectric constant, dielectric loss, and AC conductivity, were studied using LCR meters across various frequencies. AC conductivity increases with frequency while both the dielectric constant and loss decrease. These observations align with the Maxwell–Wagner polarization theory. The magnetic properties of CMC nanoparticles, such as squareness ratio (SQR = Mr/Ms), coercivity, saturation magnetization, remanence, and magnetic moment, were determined and analyzed using the vibrating sample magnetometer (VSM). [ABSTRACT FROM AUTHOR]

Cr3-substituted Co–Cu (Co0.7Cu0.3Fe2−xCrxO4) and Cu-Co (Cu0.7Co0.3Fe2−xCrxO4) nano ferrite composites were prepared using the sol–gel approach, where x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.25. We analysed their structural, DC electrical resistivity, magnetic, and dielectric properties comprehensively. X-ray diffraction (XRD) results indicate the formation of a single-phase spinel ferrite structure. The introduction of Cr3+ ions leads to a reduction in lattice volume and crystallite size. Field emission scanning electron microscopy (FESEM) images reveal non-spherical particles on a uniform surface, with a decrease in grain size as Cr3+ doping levels increase. The Fourier-transform infrared (FTIR) patterns are consistent with the XRD results, confirming the presence of spinel ferrite. The variation significantly influences the magnetic properties in Cr3+ doping. The saturation magnetization (Ms) decreases as the Cr3+ content increases to x = 0.1. Beyond that, it continues to decrease with higher Cr3+ concentrations. This behavior is attributed to the antiferromagnetic nature of Cr3+ ions, which do not favour their occupation at the B sites. The DC resistivity increases with higher Cr3+ concentrations and decreases with rising temperatures, indicating the semiconducting behavior of the ferrites. Furthermore, the loss tangent (tanδ) exhibits an exponential decrease with increasing frequency, pointing to typical Maxwell–Wagner-type dielectric dispersion driven by interfacial polarization. [ABSTRACT FROM AUTHOR]

This study used a solid-state reaction method to synthesize Cu2+ substituted Mg-Zn Mg0.5-xCuxZn0.5Fe2O4 (MgCuZn) where x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.25 ferrites effectively. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Vibrating sample magnetometer (VSM), and DC electrical resistivity analyses characterized the synthesized spinel ferrites. XRD measurements revealed the formation of cubic spinel ferrite as a single phase with crystallite sizes between 44.58–31.02 nm. As Cu2+ ion substitution increases, the lattice parameter exhibits a growth trend. The lattice parameter values showed an increase from the range of 8.413 to 8.429 Å. SEM was used to examine the surface appearance and microstructure of the ferrite samples. SEM micrographs showed that the average grain size was 1 to 2 µm. Two distinct ferrite-specific absorption bands, between 580.40–598.84 cm−1 and 402.15–405.35 cm−1, can be seen in FT-IR spectra. The saturation magnetization was between 19.66 – 53.51 emu/g, according to the Vibrating Sample Magnetometer investigation, whereas the coercivity value was between 146.33–31.43 Oe. For the prepared samples, the dc resistivity was calculated in the range 1.21 × 105 cm−1 to 2.6 × 105 cm−1 and then increased to 1.46 × 105 cm−1 with increasing Cu2+ from x = 0.0 to x = 0.25. These materials are determined to be suitable for use in high-frequency applications based on all of the findings. [ABSTRACT FROM AUTHOR]

La3+, Sm3+, Nd3+, and Gd3+substituted Co–Ni system (Co0.5Ni0.5Fe2–xRExO4; where RE3+ = La3+, Sm3+, Nd3+, and Gd3+; x = 0.0 and 0.06) ferrite materials have been synthesized using the solid-state reaction method. XRD, SEM, FTIR, DC electrical resistivity and VSM studies were carried out on these synthesized materials. It is found that RE3+ ions have substituted Fe3+ ions in the B sites. The X-ray powder diffraction pattern shows the formation of a spinel structure. No extra peak of rare earth ions was observed in the XRD pattern, possibly due to the small amount of doping of rare earth ions. The lattice parameter of the substituted ferrites is observed to increase as the ionic sizes of the RE ions increase, although fluctuations are sometimes observed. The samples are agglomerated and almost spherical, according to SEM analysis. The FTIR absorption bands represent the predicted range of spinel ferrites. D.C. electrical resistivity and saturation magnetization increase with the increase in substituted RE3+ ions. [ABSTRACT FROM AUTHOR]

The Li0.5-xNixCuxFe2.5−xO4 for x = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.25 were synthesized through the ceramic process following double sintering. Their structural, morphological, compositional, functional, and magnetic properties were analyzed with the help of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), and Vibrating Sample Magnetometer (VSM). The XRD patterns confirmed the single-phase spinel cubic structure. Lattice parameters increase from 8.3558 Å to 8.3615 Å. The increase in lattice parameter suggests the occupancy of Cu ions in the tetrahedral site, which can also be seen from the FTIR spectrum between 390 and 580 cm−1. The SEM images show the grain size in the 2.28 to 3.75 μm, whereas the porosity ranges between 4.4% and 9.7%. A squareness ratio ranges between 0.18 and 0.24; the specific magnetization is between 26 and 42 emu/g. The coercivity is observed to range between 138 Oe and 145.75 Oe. The attached EDS spectra show the composition of the samples that agree well with their stoichiometry. The VSM study shows the occupancy of copper on both A- and B-sites as observed by cation distribution. Low electric and magnetic loss, low ac conductivity, and temperature-independent electric and magnetic properties are the fundamental properties of microwave devices that were obtained for the considered composition. Therefore, the substitution gives rise to the ferrite, which is appropriate for microwave devices. [ABSTRACT FROM AUTHOR]

Background In a cohort of persons with diabetes (PWDs) seeking care at a tertiary care center, we aimed to determine the proportion of PWDs eligible and willing for down referral to primary health centers (PHCs). Methods We conducted a cross-sectional analytical study among PWDs on treatment for at least 1 year. PWDs with stable blood sugar, no history of cardiovascular events and proliferative retinopathy were considered as 'eligible' for primary care management. Results Of the total 1002 PWDs, mean (SD) age was 56 (12) years; 62% were male and 81% were from rural areas. About half (49%) of them were on insulin, and 52% had comorbidities. In total, 45.6% (95% CI: 42.3–48.8%) were eligible to be managed at PHCs. Among those who were eligible, 46.6% were willing to go back to PHCs. Males (APR = 1.16), people with diabetes for more than 10 years (APR = 1.23), and the presence of comorbidities (APR = 1.13) were significantly associated with unwillingness. Quality of medicines (46%) and poor facilities (40%) at PHCs were the main reasons for unwillingness. Conclusions About half of the PWDs availing care at tertiary hospitals can be managed at primary care settings; of those, only half were willing to receive care at PHCs. [ABSTRACT FROM AUTHOR]

A novel mesochronous pipelining scheme is described in this paper. In this scheme, data and clock travel together. At any given time a pipeline stage could be operating on more than one data wave. The clock period in the proposed pipeline scheme is determined by the pipeline stage with largest difference between its minimum and maximum delays. This is a significant performance gain compared to conventional pipeline scheme where clock period is determined by the stage with the largest delay. A detailed analysis of the clock period constraints is provided to show the performance gains and Speedup of mesochronous pipelining over other pipelining schemes. Also, the number of pipeline stages and pipeline registers is small. The clock distribution scheme is simple in the mesochronous pipeline architecture. An 8 x 8-bit carry-save adder multiplier has been implemented in mesochronous pipeline architecture using modest TSMC 180-nm (drawn length 200 nm) CMOS technology. The multiplier architecture and simulation results are described in detail in this paper. The pipelined multiplier is able to operate on a clock period of 350 ps (2.86 GHz). This is a Speedup of 1.7 times over conventional pipeline scheme, with fewer pipeline stages and pipeline registers. Index Terms--High performance, mesochronous pipeline, multiplier, pipelined system, register delays.

The content addressable memory (CAM) is a memory in which data can be accessed on the basis of contents rather than by specifying physical address. In the paper, five novel dynamic ternary CAM cells with decoupled match lines are presented. A ternary CAM cell is capable of storing and matching three values: zero (0), one (1), and don't care (X). The proposed dynamic CAM (DCAM) cells range in the number of transistors from 6 n-type transistors up to 10.5 n- and p-type transistors (one transistor is shared between two cells). The cells are capable of fast match and read operations enhancing the performance of the memory system. Using a 0.25-[micro]m CMOS technology, simulations of the proposed CAM cells were performed to compare their performance. With this technology, the shortest match delay is 89.7 ps for the 7.5 DCAM cell. A complete characterization of the five cells is provided in this paper. These results show that the novel CAM cells outperform existing cells. The compact size and low power dissipation of these ternary CAM cells make them suitable for many applications such as routers, database, and associative cache memories. Index Terms--Content addressable memory (CAM), dynamic circuits, memory cells, ternary digit (trit) operations, ternary matching.

The series of Cr-substituted Co–Cu nanoferrite materials have been developed having the chemical compositions Co0.7Cu0.3Fe2-xCrxO4, x = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.25. These ferrite materials are prepared by using the solgel auto combustion method. These materials are characterized by XRD, FESEM with EDS, HRTEM, FTIR, dc resistivity, and VSM studies. Chromium is found to occupy the B-sites replacing Fe3+ ions. The density of all the materials is found to increase except at higher values of Cr concentration. The lattice parameter of Cr-substituted ferrites is found to increase with the rise of Cr content. The dc resistivity is decreasing with an increase in temperature and thus reveals the materials' semiconductor nature. VSM study was utilized to characterize and estimate the magnetic features like magnetic saturation and the samples' coercivity. [ABSTRACT FROM AUTHOR]