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In this study, erbium-substituted Zn nanoferrites were synthesized by a simple coprecipitation method. The effect of pH on various physical parameters of erbium-substituted Zn nanoferrites was studied. The synthesized ferrite nanoparticles were characterized by XRD, FTIR, and SEM techniques and dielectric measurements. The gravimetric analysis showed the annealing temperature of these ferrites up to 700 °C. The result of XRD revealed the crystal structures of zinc nanoferrites. The FTIR spectra showed the weaker absorption peak due to Er–O stretching vibrations in zinc nanoferrites at pH 11. The SEM analysis showed that synthesized erbium-substituted Zn nanoferrites have a spherical shape with a size range from 42 to 46 nm. Dielectric properties exposed the typical semiconductor behavior of the erbium-substituted Zn nanoferrites. The electric constant at low pH was due to Fe+2 dielectric losses that dominated the sum of intrinsic and extrinsic loss. Increased in dielectric loss is associated with random crystallite orientation and impurities. The ZnFe2O4 nanoparticles with a decrease in dielectric loss revealed the crystallite orientation at pH 8 and 11. Tangent loss revealed the conductivity at higher pH 11 with a decrease in tangent loss.

The narrow optical band gap, higher electrical conductivity, and wider-absorption range are three key features that a good photocatalyst must possess. Herein, we have fabricated Cu-doped MnO2 (Mn1-xCuxO2) nanostructure by facile wet chemical approach and formed its nanocomposite with r-GO (Mn1-xCuxO2/r-GO) via ultra-sonication approach. The successful replacement of host metal ions (Mn4+) with the dopant metal ions (Cu2+) was supported with the PXRD, FT-IR, and EDX characterizations. The effect of Cu-doping on the band gap and r-GO matrix on the conductivity of the fabricated nanocomposite was also evaluated via Tauc plots and I–V tests, respectively. The photocatalytic efficiency of the fabricated photocatalysts was tested and compared against the methylene blue (MB) under visible light irradiation. The photocatalytic experiments revealed that Mn1-xCuxO2/r-GO photocatalyst exhibited superior photocatalytic aptitude than that of pristine MnO2 and Mn1-xCuxO2 photocatalysts. More precisely, the Mn1-xCuxO2 photocatalysts degraded 86.89% MB dye at the rate of 0.021 min−1 after a 90-min exposure to the visible light. Observed superior catalytic activity of the nanocomposite can be attributed to the synergistic effects between the Cu doped MnO2 and r-GO nanosheets that resulted in its narrow band-gap (2.19 eV) and excellent conductivity (2.217 × 10−2 Scm−1).

In the present study, stabilizer caged fluorescent rhodamine B mesoporous silica particles with special shapes were prepared. The prepared particles have a pore volume of 1.92 cm3/g and a pore diameter of 12 nm. The abundant hydroxyl functional groups of mesoporous silica are responsible for the superior loading capacity of target molecular specie. The appearance of bands due to –COOH, –CH3, –CH2, –NH etc. indicated that the fluorescent rhodamine B could be encaged with the stabilizer inside the mesoporous channels. The performance of mesostructured origami silica matrix was evaluated by in vitro release experiments. From the in vitro release results, this material is suggested to have appropriate features for almost no release at pH = 1.2 and very slow release at neutral pH value. The same material could be best employed at pH 4.5 and at high pH values. It is concluded that mesostructured origami silica matrix is a smart nano-platform and can be utilized for high retention of cargo molecules.

Ketotifen fumarate, a mast cell stabilizer, and salbutamol sulfate, a bronchodilator, are frequently prescribed together for chronic asthma. This study aimed to combine both anti-asthmatic drugs in single polymeric responsive matrix type transdermal patches. Drug release from polymeric device was optimized by varying ratios of hydrophilic (polyvinyl pyrrolidone) and hydrophobic (ethyl cellulose) polymers. Propylene glycol was used as plasticizer and solvent system including mixture of chloroform and methanol. Physicochemical evaluations like thickness, weight variation, folding endurance, tensile strength, content uniformity and % moisture absorbance of developed patches were carried out. Developed patches were also subjected for in vitro release of drugs, and formulation of P6 with equal proportion of polyvinyl pyrrolidone and ethyl cellulose found optimized formulation with respect to release rate of both drugs. 76.49% of ketotifen fumarate and 77.49% of salbutamol sulfate were released from P6, and release of both drugs sustained up to 24 h. In the next step, permeability enhancers like Tween 20, isopropyl myristate, eucalyptus oil and span 20 were added to the formulation P6 and subjected to in vitro permeation study on Franz diffusion cell using rabbit skin. Results of in vitro permeation study revealed that transdermal patches with permeation enhancers permeate the significant amount of drugs in comparison with the formulation without enhancer.

A multipurpose, environment-friendly, and effective catalyst for control of environmental contaminants is an enduring interest in recent years. In the present study, lanthanum substituted spinel ferrite (LaxMnFe2-xO4) nanoparticles were synthesized using an eco-friendly, low cost-effective reverse-micelle synthesis strategy. Thermal analysis was done to annualize the annealing temperature of prepared precipitates. X-ray diffraction (XRD) study revealed the well-defined cubic spinel structure of LaxMnFe2-xO4 with the presence of a very minute secondary phase by the introduction of La3+ ion. Fourier transform infrared spectroscopy (FTIR) study confirmed the M − O metal-oxygen bond stretching at tetrahedral and octahedral sites. Surface morphology analyzed by field emission scanning electron microscopy (FESEM) revealed the narrow size distribution having nanoparticles size of nearly 60 nm. From the bandgap study, an enhanced redshift of 2.40 eV directed its semiconductor photocatalysis behavior. The degradation efficiency of pristine MnFe2O4 and La3+ ion substituted MnFe2O4 material was investigated using a contaminant crystal violet dye. Higher degradation efficiency, kinetic investigation smart degradation mechanism, and simple recovery suggested that the newly designed La3+ ion substituted MnFe2O4 photocatalytic material is best for environmental remediation.

In this research paper, we have reported the thermal, structural, magnetic and optical properties of unsubstituted and aluminum substituted zinc ferrite nanoparticles. These substituted and unsubstituted ferrite nanoparticles were prepared by cost effective co-precipitation method. The co-precipitated unannealed nanoparticles of the typical sample were subjected to thermogravimetric analysis (TGA) to probe the annealing temperature. The X-rays diffraction (XRD) technique was used for the determination of structural parameters. XRD patterns of all compositions of AlxZnFe2-xO4 nanoparticles confirmed the FCC structure of these spinel ferrite nanoparticles. Besides the main crystal structure determination, many other lattice parameters and their variations with respect to increased Al3+ contents in ZnFe2O4 were also calculated from XRD data and have been discussed in detail in this article. The morphology of the synthesized materials has been studied by scanning electron microscopy (SEM) and average particles size found

In this work, nanocrystalline NiDyxFe2-xO4 ferrites (0.0 ≤ x ≤ 0.1) were synthesized via co-precipitation route. The impact of Dy+3 substitution on the various properties has been investigated. Structural, electrical, spectral and magnetic parameters were measured by XRD (X-ray diffraction), I–V (current-voltage), FTIR (Fourier transform infrared spectroscopy) and VSM (vibrating sample magnetometer) respectively. Morphological analysis was done by FE-SEM (Field emission scanning electron microscope). The formation of a single-phase FCC cubic spinel structure was confirmed by XRD patterns. With the help of XRD data, bond lengths and ionic radii were also calculated. FTIR spectra showed the formation of two typical frequency bands (υ1 and υ2) which represent metal-oxygen (M–O) vibrations at octahedral (B) and tetrahedral (A) sites. EDX spectrographs confirmed elemental composition. The M H curves demonstrated a decrease in saturation magnetization (Ms) and Bohr magneton (nB). The coercivity (Hc) showed a non –linear behaviour while anisotropy constant first increased and then decreased with Dy-substitution. NiDy0.025Fe1.975O4 showed maximum coercivity (102.06 Oe).

Department of Chemistry, Institute of Natural Sciences, University of Gujrat, Gujrat 50700, Pakistan The surfactant assisted co-precipitation method has been used to synthesize the Co2+ and Ni2+ substituted magnesium nanoferrites. The Co2+ and Ni2+ ions substitute the Mg2+ and Fe3+ ions from the magnesium ferrites, respectively. To study the effect of substituted ion concentrations on the dielectric performance of the MgFe2O4 spinel ferrites. The substituted magnesium nanoferrites with the compositions Mg1-x Cox NiyFe2-yO4 (x, y = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) were synthesized to notice the effect of substituted ions concentration on the dielectric properties. Thermogravimetric analysis of the precursor precipitates was taken to investigate the stable spinel phase formation temperature. The X-ray diffraction analysis of the all substituted samples confirms the successful formation of the stable spinel phase and also exposes the effects of substituted ions on the crystal structure and unit cell constants. The presence of a characteristic absorption band (400 cm−1, 550 cm−1) of spinel ferrites in the Fourier Transform Infra Red (FT-IR) spectrum of substituted magnesium nanoferrites also confirms the formation of desire phase. The effect of temperature on the conductivity of the all substituted samples was observed within the temperature range of 25°C–300°C by two-probe direct current electrical resistivity measurements. Dielectric measurements of the substituted magnesium nanoferrites were carried out to study their magnetic behavior. The inverse relation of the dielectric parameters of the all substituted magnesium nanoferrites with frequency shows their excellent potential for devices that operate at higher frequencies.Department of Chemistry, University of Okara, Renala Khurd, Okara, Pakistan Department of Chemistry, Allama Iqbal Open University, H-8, Islamabad 45320, Pakistan.

In this study, optimized micro-emulsion route was utilised to synthesize the Cr-substituted MnFe2O4 nanoparticles. Transition metal Cr3+ cations were used to replace the Fe3+ ions because the Cr3+ ions have compatible ionic radii and are non-magnetic in nature. Further, they have the same electronic configuration, which is the primary requirement for the substitution philosophy. Cr3+ (x) contents were in the range 0 ≤ x ≥ 0.16. All derivative of manganese ferrite nanoparticles were annealed at 400 °C. The annealing at the required temperature was carried out for 4 hours under vacuum. Structural information was collected via X-ray diffraction (XRD) analysis and Fourier transform infra-red (FTIR) spectroscopy. Both XRD and FTIR confirmed FCC structure of all compositions of CrxMnFe2-xO4 nanoparticles. Various other physical parameters like lattice constant, cell volume, X-ray density, crystallite size were determined from obtained XRD data. Quantitative measurement of both divalent (Mn2+) and trivalent (Fe3+ and Cr3+) transition metal cations was calculated. FTIR spectral investigation was done to confirm the two typical bands corresponding to metal-oxygen vibrations present at A-sites and B-sites. After structural and spectral investigations, the electrical and dielectric properties were studied in detail for utilization of these ferrites for practical applications. Both electrical and dielectric properties were found in agreement with each other. The dielectric properties were carried out in frequency range 1 × 106 Hz to 3 × 109 Hz. In general, the both electrical and dielectric parameters were largely affected by Cr-substitution in MnFe2O4 nanoparticles.

In this work, fabrication of Gd3+ substituted nickel spinel ferrite (NiGdxFe2-xO4) nanoparticles was carried out via co-precipitation route. X-ray powder diffraction (XRD) confirmed the spinel cubic structure of NiGdxFe2-xO4 nanoparticles. XRD data also facilitated to determine the divalent and trivalent metal cations distribution at both A and B sites of the ferrite lattice. Site radii, hopping and bond lengths were also calculated from XRD data. The spectral studies elucidated the formation of cubic spinel ferrite structure as well as stretching vibrations of M–O (metal–oxygen) bond at A and B sites of ferrites, represented by two major bands υ1 and υ2 respectively. FESEM analysis confirmed the irregular morphology of NiGdxFe2-xO4 nanoparticles. EDX spectrographs estimated the elemental compositions. The dielectric attributes were explained on the basis of the Debye-relaxation theory and Koop’s phenomenological model. At higher applied frequencies (AC) no prominent dielectric loss was observed. Magnetic parameter variations can be attributed to the substitution of the rare earth cations having larger ionic radii as compared to the radii of Fe3+ ions. Moreover, spin canting, magneto-crystalline anisotropy and exchange energy of electrons also helped in magnetic evaluation. Due to small coercivity values NiGdxFe2-xO4 nanoparticles can be employed significantly in high-frequency data storage devices.

In this paper, the detailed study of magnetic properties of Dy3+ substituted soft manganese ferrite (MnFe2O4) nanoparticles with varied contents of Dy3+ ions (0.00 ≤ x ≤ 0.16) was carried out by vibrating sample magnetometery (VSM) at room temperature. The synthesis of reported magnetic materials was carried out via facile wet chemical route. Structural characterization was investigated via X-ray diffraction and infra-red spectroscopy. Exploration of magnetic measurements revealed an irregular behavior in the values of saturation magnetization (Ms), remanent magnetization (Mr), and coercivity (Hc) depending upon the concentration of rare-earth ions (Dy3+). The fluctuations in the values of Ms, Mr, and Hc may be associated with the modifications in the spin-exchange interactions caused by structural changes due to the substitution of rare-earth ions (Dy3+). DC electrical resistivity values were recorded and were found to be increased with increased Dy3+ contents. The soft magnetic nature of Dy3+ substituted MnFe2O4 spinel ferrites nanoparticles suggested their possible utilization in switching mode power supplies, recording media, spintronics, and many other advanced technological devices.

In this study, we substituted the magnetic Fe3+ ions with highly paramagnetic rare earth Dy3+ cations in MnFe2O4 spinel ferrite nanoparticles to investigate the physical, structural, spectral and electrical properties in detail. Dysprosium substituted inverse spinel ferrite nanoparticles (DyxMnFe2-xO4) (0 ≤ x ≥ 0.16) were prepared via facile optimized wet chemical approach i.e. micro-emulsion route. Substituted and unsubstituted manganese ferrite nanoparticles were annealed at 400 °C for 4 h under vacuum. X-ray diffraction (XRD) analysis proved the spinel structure of all compositions of DyxMnFe2-xO4 nanoparticles. Various physical parameters were calculated from XRD data. Quantitative measurements of cations distribution were carried out to estimate the distribution of divalent metal cations (Mn2+) and trivalent metal cations (Fe3+ and Dy3+) between A-sites (tetrahedral) and B-sites (octahedral). Oxygen parameter ‘u’ was calculated to study the displacement of oxygen ions in tetrahedral sites along (111) direction. Fourier transform infrared spectra (FTIR) were recorded to study the two significant absorption bands corresponding to A-site and B-site. Scanning electron microscopic (SEM) analysis was carried out to study the morphology of DyxMnFe2-xO4 nanoparticles. After structural and morphological investigations, all compositions of DyxMnFe2-xO4 nanoparticles were subjected to dielectric parameters measurements. The dielectric parameters like dielectric constant (real and imaginary part) and tangent loss were investigated as a function of frequency from 1 MHz to 3 GHz at room temperature.

New yttrium substituted manganese ferrite (MnYxFe2-xO4) nanoparticles (NPs) were prepared by low cost reverse micelle micro-emulsion method by utilizing cheap raw materials like Paraffin, Triton X-100, and 1-butanol and corresponding metal salts. The Y3+content (x) range was kept 0 ≤ x ≤ 0.16. Thermogravimetric analysis (TGA) of un-annealed precipitates was carried out to probe the phase formation temperature. The annealing of precipitates of all compositions of MnYxFe2-xO4 nanoparticles was carried at 400 °C for 4 h (h). The annealing was carried out under vacuum to control the oxidation of manganese. The effect of Y3+ cations on structural, spectral and dielectric properties was investigated by X-ray diffraction (XRD), Fourier Transform Infra-Red (FTIR) spectroscopy and impedance analyzer measurements at room temperature. XRD patterns confirmed the formation of MnFe2O4 and its derivatives with yttrium. Site radii and bond lengths were calculated from XRD data. FTIR spectra confirmed the tetrahedral (A) and octahedral (B) sites in all compositions of MnYxFe2-xO4 nanoparticles, which is characteristic of spinel ferrites having FCC (face centered cubic) structure. Scanning electron microscopic (SEM) analysis confirmed the spherical morphology of ferrite particles. Dielectric parameters analysis in the frequency range from 1 × 106 Hz to 3 × 109 Hz suggested that these ferrite particles may find their potential applications in high frequency devices fabrication.

Background: Spinel ferrites have great scientific and technological significance because of their easy manufacturing, low cost and outstanding electrical and magnetic properties. Nickel ferrite nanoparticles are ferromagnetic material with an inverse spinel structure. They show remarkable magnetic properties and hence have a wide range of applications in magnetic storage devices, microwave devices, gas sensors, telecommunication, drug delivery, catalysis and magnetic resonance imaging. Objective: The aim and objective of this research article is to study the relative effect of NiErxFe2-xO4 nanoparticles and their composites with reduced graphene oxide (rGO) for the photocatalytic degradation reaction and other physical parameters. Method: Rare earth Er3+ substituted NiErxFe2-xO4 nanoparticles were synthesized via the facile wet chemical route. Six different compositions of NiErxFe2-xO4 with varied Er3+ contents such as (x) = 0.00, 0.005, 0.01, 0.015, 0.02 and 0.025 were selected for evaluation of the effect of Er3+ on various parameters of NiFe2O4 nanoparticles. Reduced graphene oxide (rGO) was prepared by Hummer’s method and was characterized by UV-Visible spectroscopy, X-ray powder diffraction and Raman spectroscopy. Nano-heterostructures of NiErxFe2-xO4 with rGO were prepared by the ultra-sonication method. Results: X-ray powder diffraction (XRD) confirmed the spinel cubic structure of all the compositions of NiErx- Fe2-xO4 nanoparticles. The photocatalytic degradation rate of methylene blue and congo red under visible light irradiation was found faster in the presence of NiErxFe2-xO4-rGO nanocomposites as compared to bare nanoparticles. It was also investigated that as the Er3+ contents were increased in NiErxFe2-xO4 nanoparticles, the dielectric parameters were largely affected. The room temperature DC-resistivity measurements showed that the Er3+ contents in NiFe2O4 are responsible for the increased electrical resistivity of ferrite particles. The electrochemical impedance spectroscopic (EIS) analysis of NiErxFe2-xO4 nanoparticles and NiErxFe2-xO4-rGO nanocomposites revealed that the ferrite particles possess low conductance as compared to the corresponding composites with graphene. Conclusion: The data obtained from all these characterization techniques suggested the potential applications of the NiErxFe2-xO4 nanoparticles and NiErxFe2-xO4-rGO nanocomposites for visible light driven photo-catalysis and high-frequency devices fabrication.

In this work erbium (Er3+) substituted cobalt zinc ferrite having general formula Co0.70Zn0.30ErxFe2-xO4 (x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) were fabricated using micro-emulsion technique. The substitution of Er was done for the purpose of tuning the optical band gap. Er+3 substituted nanoparticles were annealed at 700 °C for 7 h. A typical composition of Co0.70Zn0.30ErxFe2-xO4 was utilized to make the nanocomposites material with reduced graphene oxide (rGO), that was prepared by facile chemical route. The main purpose of graphene was to enhance the conductivity of ferrite particles. All these ferrite particles and a composite were characterized by X-rays diffraction (XRD), UV–Visible spectroscopy and SEM for structural elucidation and morphology studies. Single phase spinel structure was confirmed by XRD analysis and crystallized size calculated by Scherer formula was found in the range 35–60 nm. SEM confirmed the well dispersed ferrite particles among graphene sheets. All the Er-substituted ferrite particles were subjected to dielectric parameters study. One typical composition of Co0.70Zn0.30ErxFe2-xO4 particles and its composites with rGO were utilized for photocatalysis study using methylene blue as model organic compound in the presence of visible light. Current-voltage (I-V) measurements of ferrites nanoparticles and their composites with graphene were also studied. The results of all these techniques were agreed with each other and suggested the various potential applications of these nanoparticles.

Background and objective Acute pulmonary embolism (APE) is a serious cardiovascular emergency, mainly secondary to deep vein thrombosis (DVT), which causes death. The goal of the current study was to determine the levels of different serum markers in combination among patients with and without acute pulmonary embolism in order to use them as a diagnostic tool. Methodology A sample of 96 patients was kept with a 90% power of study and a 5% level of significance in the current study. It was carried from January to June 2020 in the Department of Medicine, Bahawal Victoria Hospital, Bahawalpur, after the hospital’s Ethical Committee approval. Written informed consent was taken. Serum levels of C-reactive protein (CRP), D-dimer, fibrinogen, and Troponin-I between both groups were done once enrolled. SPSS software, version 25 (IBM Corp. Armonk, NY) was used to analyze the collected data. Results Patients with acute pulmonary embolism had a mean age of 50.4 ± 10.4 years. All serum markers were significantly raised in patients suffering from acute pulmonary embolism with a p-value of

An efficient, environment-friendly and economical catalyst to control contaminants of environment is an enduring interest in recent years. In this study, a new composite, Dy

Brain tumor localization and segmentation from MRI of the brain is a significant task in medical image processing. Diagnosis of brain tumors at early stages play a vital role in successful treatment and raise the survival percentage of the patients. Manual separation of brain tumors from huge quantity of MRI images is a challenging and time taking task. There is need for an automatic efficient technique for brain tumor localization and segmentation from MRI images of brain. Some years ago, improper filtration and segmentation techniques was used for brain tumor detection, which gives almost inaccurate detection of tumor in MRI images. The proposed technique is mainly based on the preprocessing step for de-noising input MRI, thresholding, and morphological operation and calculating performance parameters for validation. Firstly, anisotropic diffusion filter is applied for removal of noise because input MRI images are mostly noisy and inhomogeneous contrast. Secondly, MRI pre-processed brain image is segmented into binary using thresholding technique. Thirdly, the region-based morphological operation is used for separation of tumorous part from segmented image. At the end, Root mean square error (RMSE), peak signal to noise ratio (PSNR), tumorous area in pixels and centimeters, system similarity index measurement (SSIM), area under curve (AUC), accuracy, sensitivity and specificity are the parameters used for evaluation of the proposed methodology. Visual and parametric results of proposed method are compared with the existing literature.

Automated brain tumor detection is an important application in the medical field. There is a lot of methods developed for this task. In this paper, we have implemented an algorithm which detects the type of brain tumor from MRI image using supervised classification techniques. The major part of the work includes feature extraction using DWT and then reduction of features by using PCA. These reduced features are submitted to different classifiers like SVM, k-NN, Naive Bayes and LDA. The results from each classifier are then submitted to a voting algorithm that chooses the most frequent result. The dataset for training contains 160 MRI images. The algorithm is processed on 200 * 200 images to reduce processing time. This method is tested and found to be much beneficial and rapid. It could be utilized in the field of MRI classification and can assist doctors to detect the tumor type and diagnose about patient abnormality level.

La3+ ions substituted manganese ferrite (MnFe2-x La x O4) nanoparticles via reverse micelles strategy were synthesized and their structural and electrical properties are discussed in this article. Using low-cost precursors, mono-dispersed, and well crystalline MnFe2-x La x O4 nanoparticles were prepared at low temperature. X-ray diffraction (XRD) explored cubic spinel structure with minute secondary phase as LaFeO3. The crystallite size of MnFe2-x La x O4 was found to increase from 12.82 nm to 15.95 nm with increased La3+ ions contents. The room temperature Fourier transform infrared (FTIR) spectra were recorded in the wavenumber range 1000–400 cm−1 that showed the vibrational bands of octahedral and tetrahedral complexes. These bands are the fingerprints of spinel ferrites. Surface morphology characterized by field emission scanning electron microscopy (FESEM) revealed the relative spherical morphology of prepared spinel ferrite particles. The elemental composition analysis from Energy-dispersive x-ray (EDX) spectroscopy confirmed the presence of expected elements in the samples. The modification in resistivity and the enhancement in the dielectric parameters suggested the possible utilization of these soft ferrite nanoparticles in advanced electronics, especially the devices that are required to operate at high frequencies.

Polycrystalline ErxNi0.8Zn0·2Fe2-xO4 nanoparticles were synthesized using wet chemical route. Powder x-ray diffraction (XRD) data was utilized to observe the structural parameters. The cubic crystalline structure with the second phase was obtained from XRD patterns. Two significant absorption bands (between 700 and 400 cm−1) at the tetrahedral and octahedral sites were studied from Fourier transform infrared spectroscopy (FTIR) that further confirmed the spinel structure of prepared ferrites. These are the main bands of spinel ferrites. After the structural explanation, the dielectric, electrical and magnetic parameters were studied in detail at room temperature. All of these parameters were affected by Er3+ substitution. The obtained results suggested the possible utilization of these soft ferrites in advanced technological applications such as the devices working at high frequencies, magnetic data recording, switching applications, etc.

An efficient, environment-friendly and economical catalyst to control contaminants of environment is an enduring interest in recent years. In this study, a new composite, DyxMnFe2-xO4nanoparticles decorated over mesoporous silica was synthesized and utilized for removal of organic pollutant. Highly crystalline nature of DyxMnFe2-xO4 nanoparticles and amorphous nature of material was confirmed by XRD (X-ray diffraction) technique. Infrared spectra of fabricated material before and after adsorption of dye molecules evidenced the successful adsorption of dye molecules by fabricated adsorbent. From field emission scanning electron microscopic (FESEM) images of Dy3+ substituted MnFe2O4 composite with mesoporous silica, it was clearly observed that ferrite particles of size 20-30 nm were decorated on the surface of mesoporous silica particles and distributed well over spherical silica balls homogeneously. Its magnificent mesoporous nature was revealed from BET (nitrogen adsorption-desorption measurements) analysis. Surface area, pore volume and average pore size was found 387.95 m2/g, 0.390 cm3/g and 4.02 nm respectively. Tri-modal pore size distribution showed its effective utilization in adsorption. The abundant (SiOH) hydroxyl groups of mesoporous silica, the broad diffraction hump of silica depicted its superior loading capacity of target molecular specie inside its porous network. From band gap analysis, a red shift of 2.43 eV exhibited semiconductor photocatalysis of DyxMnFe2-xO4 nanoparticles. Degradation efficiency of bare MnFe2O4, DyxMnFe2-xO4 and mesoporous silica-based composite was tested using crystal violet dye. Its explored adsorption-photocatalysis synergy, degradation mechanism, kinetic investigation, easily recovery and remarkable recycling ability suggested that the new fabricated composite is best for environmental remediation.

Transition metal spinel type mixed oxides (FeCo2O4, MnCo2O4 and ZnCo2O4) nano-catalysts have been synthesized via co-precipitation route. The samples were characterized using XRD and FE-SEM techniques to determine structure and morphologies respectively. Furthermore, FTIR and BET analysis were carried out in order to confirm the structure and calculate surface areas of the samples. The photocatalytic potency of synthesized nano-catalysts have been examined for aqueous solution of methylene blue under visible light. It is found that photocatalytic activity of simple transition metal oxides was enhanced by making their binary/ternary metal oxides. FeCo2O4 exhibited highest photocatalytic efficiency among the prepared spinel structures while MnCo2O4 possess lowest efficiency. The photocatalytic behavior of mixed transition metal oxides can be accredited to its spinel structure, small particle size and large surface area. XRD and BET results revealed the small crystallite and particle size of spinel mixed oxides. The small crystallite size of spinel mixed oxides nano-structures contributes to increased photocatalytic activity by increasing the surface area of photocatalyst, decreasing the chance of reunion of charge carriers. It is observed that these binary oxide nano-structures have potential applications in heterogeneous photo decay of environmental contaminants and can act as propitious materials for resolving environmental issues and establishing green environment.

Polycrystalline oxide YxMnFe2−xO4 was prepared via low-cost micro emulsion method. As concentration of yttrium ions increased, their electrical and magnetic properties were changed. Effect of secondary phase YFeO3 on the electrical and magnetic properties of the material were also studied and discussed in detail. As concentration of impurity ions increased, variation in resistivity was observed. This variation also affected the magnetic behavior of the prepared Mn-based spinel ferrites. Various parameters such as the saturation magnetization (Ms), retentivety (Mr), coercivity (Hc), anisotropic constant (k1), magnetic moments (μB) have been calculated from recorded M-H loops of all unsubstituted and substituted MnFe2O4 nanoparticles. Ms and Mr values found in the range 27–50 emu/g and 1.8–7.6 emu/g respectively.

The mechanism responsible for the emission of clusters from heavy ion irradiated solids is proposed to be thermal spikes. Collision cascade-based theories describe atomic sputtering but cannot explain the consistently observed experimental evidence for significant cluster emission. Statistical thermodynamic arguments for thermal spikes are employed here for qualitative and quantitative estimation of the thermal spike-induced cluster emission from silicon, germanium and zinc oxide. The evolving cascades and spikes in elemental and molecular semiconducting solids are shown to have fractal characteristics. Power law potential is used to calculate the fractal dimension.The fractal dimension is shown to be dependent upon the exponent of the power law interatomic potential. Each irradiating ion has the probability of initiating a space-filling, multi-fractal thermal spike that may sublime a localized region near the surface by emitting clusters in relative ratios that depend upon the energies of formation of respective surface vacancies.

A cross sectional study was conducted to observe the factors affecting the productive performance of dairy cattle from northern rural areas of Bangladesh during July and September 2013. Data of 105 cows, 85 (80.95%) from local and 20 (19.05%) cows from cross breed, were randomly selected for the study. A binary logistic regression, expressed by odds ratio with 95% confidence interval, was done to determine the association of daily milk production categorized into ? 2 and > 2 liters (L), based on median, with the significant explanatory variables of body weight, age at first calving, lactation period, vitamin use, type of floor and milking person. The result demonstrated that the probability of milk production of >2 L was 6.16, 4.5, 20.65 and 5.7 times higher from the with animal body weight of >140 kg, age at first calving of >36 m, lactation period of >8 m and vitamin use than that of body weight of 140 kg, age at first calving of ?36 m, lactation period of ? 8 m, and not vitamin used respectively. The chance of milk production of > 2 L was 0.25 and 0.22 times lower for mud floor, and owner milking than that of brick floor and gowala (professional milking person) respectively. DOI: http://dx.doi.org/10.3329/ijarit.v4i2.22646 Int. J. Agril. Res. Innov. & Tech. 4 (2): 41-45, December, 2014