190 research outputs found
Ferromagnetism and the Effect of Free Charge Carriers on Electric Polarization in Y_2NiMnO_6 Double Perovskite
The double perovskite Y_2NiMnO_6 displays ferromagnetic transition at Tc = 81
K. The ferromagnetic order at low temperature is confirmed by the saturation
value of magnetization (M_s) and also, validated by the refined ordered
magnetic moment values extracted from neutron powder diffraction data at 10 K.
This way, the dominant Mn4+ and Ni2+ cationic ordering is confirmed. The
cation-ordered P 21/n nuclear structure is revealed by neutron powder
diffraction studies at 300 and 10 K. Analysis of frequency dependent dielectric
constant and equivalent circuit analysis of impedance data takes into account
the bulk contribution to total dielectric constant. This reveals an anomaly
which coincides with the ferromagnetic transition temperature (T_c).
Pyrocurrent measurements register a current flow with onset near Tc and a peak
at 57 K that shifts with temperature ramp rate. The extrinsic nature of the
observed pyrocurrent is established by employing a special protocol
measurement. It is realized that the origin is due to re-orientation of
electric dipoles created by the free charge carriers and not by spontaneous
electric polarization at variance with recently reported magnetism-driven
ferroelectricity in this materialComment: Published in Physical Review
Griffiths phase-like behaviour and spin-phonon coupling in double perovskite TbNiMnO
The Griffiths phase-like features and the spin-phonon coupling effects
observed in TbNiMnO are reported. The double perovskite compound
crystallizes in monoclinic space group and exhibits a magnetic phase
transition at 111 K as an abrupt change in magnetization. A negative
deviation from ideal Curie-Weiss law exhibited by 1/ curves and
less-than-unity susceptibility exponents from the power-law analysis of inverse
susceptibility are reminiscent of Griffiths phase-like features. Arrott plots
derived from magnetization isotherms support the inhomogeneous nature of
magnetism in this material. The observed effects originate from
antiferromagnetic interactions which arise from inherent disorder in the
system. Raman scattering experiments display no magnetic-order-induced phonon
renormalization below in TbNiMnO which is different from the
results observed in other double perovskites and is correlated to the smaller
size of the rare earth. The temperature evolution of full-width-at-half-maximum
for the {\it stretching} mode at 645 cm presents an anomaly which
coincides with the magnetic transition temperature and signals a close
connection between magnetism and lattice in this material.Comment: 17 pages, 8 figures; accepted in J. Appl. Phy
A randomized controlled comparative clinical trial on Jwarahara effect of Mukkaamukkatukaadi Syrup with Kiratatikta Syrup in Febrile Children
Ayurvedic classics have described many diseases amongst which Jwara stands first because of its uniqueness to make everyone suffer, since birth to death. Jwara being one of the commonest symptoms which accompanies almost all constitutional diseases has been coined with the term Rogadhipathi. Fever is defined as temperature in rectum more than 100.4°F (38°C), in oral cavity above 99.5°F (37.5°C) or in axilla above 99°F (37. 2°C). If we don’t treat fever in its earlier stage, there will be more chances of hyperpyrexia which may cause febrile convulsions which leads to brain damage. Therefore, it is necessary to control fever at its earlier stage. One such Jwarahara formulation is Mukkaamukkatukaadi Gulika and Kiratatikta which is converted into syrup form to overcome the palatability issues. A sample size of 30 patients was selected by simple random sampling method and 15 patients were allotted in two groups. It was planned to compare the result between Mukkaamukkatukaadi syrup in Group A study group for STG and LTG and Kiratatikta syrup in Group B control group for STG and LTG. On STG comparison, the difference in mean in Group A and Group B were 0.49,0.44 before treatment changed to 0.96 and 0.98 after treatment respectively. On LTG comparison, the difference in mean in Group A and Group B were 0.49, 0.44 before treatment changed to 2.02 and 1.96 after follow up respectively. This depicts both the formulations effective when consumed for longer duration. From the results and observations it can be concluded that Group A and Group B are equally effective and equally significant on reducing the temperature in both STG and LTG. No adverse drug reaction was found during the study
Dog Breed Identification using ResNet Model
As dogs are domestic animals due to the many numbers of dog breeds available around the world. It’s hard to find out the exact dog breed name for a common person. There are many techniques available to identify dog breed. But the proposed work introduced the new technique called RESNET which is the part of CNN to classify dog. RESNET is used to identify images. It helps to perform different tasks on larger datasets. Identification of different dogs is one of the important applications of Convolutional Neural networks. Since the identification of dog breeds is very difficult because they spread in a large number and it makes very hard for a person to identify or classify dogs. With the help of Keras and TensorFlow, a dataset is created, tested, and trained for the detection of dog breeds by using RESNET. Around 120 different dog breeds are present in the dataset which consist of 20600 images of dogs. From this paper, load these images and convert them into a NumPy array and normalize them. Then,100 epochs were used with a batch size of 128 to achieve the best accuracy. The model is saved for further process to create a web application to identify the dog
Electronic structure of Pr2MnNiO6 from x-ray photoemission, absorption and density functional theory
The electronic structure of double perovskite Pr2MnNiO6 is studied using core
x-ray photoelectron spectroscopy and x-ray absorption spectroscopy. The 2p
x-ray absorption spectra show that Mn and Ni are in 2+ and 4+ states
respectively. Using charge transfer multiplet analysis of Ni and Mn 2p XPS
spectra, we find charge transfer energies {\Delta} of 3.5 and 2.5 eV for Ni and
Mn respectively. The ground state of Ni2+ and Mn4+ reveal a higher d electron
count of 8.21 and 3.38 respectively as compared to the atomic values of 8.00
and 3.00 respectively thereby indicating the covalent nature of the system. The
O 1s edge absorption spectra reveal a band gap of 0.9 eV which is comparable to
the value obtained from first principle calculations for U-J >= 2 eV. The
density of states clearly reveal a strong p-d type charge transfer character of
the system, with band gap proportional to average charge transfer energy of
Ni2+ and Mn4+ ions.Comment: 18 pages, 9 figure
BIOLOGICAL AERATED FILTERS (BAFs) FOR CARBON AND NITROGEN REMOVAL: A REVIEW
Biological aerated filters (BAFs) are an emerging wastewater treatment technology designed for a wide range of municipal and industrial applications. This review paper presents and discusses of the influence C/N ratio, nitrification and denitrification principle, effect of pH, DO and alkalinity on the nitrification and denitrification systems, organic and hydraulic loading of BAF reactor, etc. Results from upflow and downflow biofilter pilot at different condition, with nitrification and denitrification are reviewed. Under the optimal conditions, significant amount of COD, ammonia-nitrogen and total nitrogen were removed. Removal rates based on reactor volume for different carbon-aceous COD and ammonia loading rate are reported. The BAF system for the nitrification and denitrification processes for carbon and nitrogen removal from the wastewater need to be evaluated and applied properly to protect of our environment and resources
CblC Type Methylmalonic Aciduria with a Novel Homozygous Mutation: A Case Report
Background CombinedMethylmalonic Aciduria (MMA), and homocystinuria CblC type is the most common inborn error of cobalamin metabolism with 77 mutations identified till date in the MMACHC gene. The disease has early and late presentations with varied clinical features. Case report A pair of preterm monochorionic twins was born to non-consanguineous parents with history of 2 previous infant deaths with suspected MMA. The twins became symptomatic in second week with severe neutropenia, thrombocytopenia, progressive encephalopathy and eczema without anemia, metabolic acidosis or hyperammonemia. Investigation revealed elevated plasma Complement 3 (C3) acyl carnitine and very high MMA levels in urine. Genetic testing revealed a novel large deletion mutation in chromosome 1 which comprised of the whole MMACHC gene confirming the diagnosis of CblC type of MMA. The mutation was homozygous despite parents being unrelated and was identified in both parents later. Both twins responded transiently to treatment with hydroxycobalamin. Conclusion Large deletion in the MMACHC genewhich was identified in a homozygous state in our twins is previously unreported. The phenotypic features are described
Probing magnetic anisotropy and spin-reorientation transition in 3D antiferromagnet, HoDyFeOPt using spin Hall magnetoresistance
Orthoferrites (FeO) containing rare-earth () elements are 3D
antiferromagnets (AFM) that exhibit characteristic weak ferromagnetism
originating due to slight canting of the spin moments and display a rich
variety of spin reorientation transitions in the magnetic field
()-temperature () parameter space. We present spin Hall magnetoresistance
(SMR) studies on a -plate (-plane) of crystalline
HoDyFeOPt (HDFOPt) hybrid at various in the
range, 11 to 300 K. In the room temperature phase,
the switching between two degenerate domains, and
occurs at fields above a critical value, Oe. Under , the angular dependence of SMR
(-scan) in the phase yielded a highly skewed
curve with a sharp change (sign-reversal) along with a rotational hysteresis
around -axis. This hysteresis decreases with an increase in . Notably, at
, the -scan measurements on the single domain,
exhibited an anomalous sinusoidal signal of
periodicity 360 deg. Low- SMR curves ( = 2.4 kOe), showed a systematic
narrowing of the hysteresis (down to 150 K) and a gradual reduction in the
skewness (150 to 52 K), suggesting weakening of the anisotropy possibly due to
the -evolution of Fe- exchange coupling. Below 25 K, the SMR modulation
showed an abrupt change around the -axis, marking the presence of
phase. We have employed a simple Hamiltonian and
computed SMR to examine the observed skewed SMR modulation. In summary, SMR is
found to be an effective tool to probe magnetic anisotropy as well as a spin
reorientation in HDFO. Our spin-transport study highlights the potential of
HDFO for future AFM spintronic devices.Comment: 12 pages, 7 figure
Wild relative of turmeric, Curcuma zanthorrhiza Roxb.- A source of edible starch
Curcuma zanthorrhiza Roxb., a wild relative of turmeric belongs to the family Zingiberaceae, is an important under exploited rhizomatous herb. Inspite of its medicinal uses, the traditional benefits extends to the isolation of starch powder from its rhizomes, and could be used as nutritional supplement like arrowroot powder. In the present study, the crude starch powder was isolated from the rhizomes of C. zanthorrhiza, was subjected to various characterization and acute oral toxicity study. The results showed that the starch recovery percentage of C. zanthorrhiza as 10.40±3.65 and the presence of the coumarin and natural colourant curcumin content on the isolated crude starch powder. Relatively very small amount of moisture, crude protein, fat, fibre, and ash content was noticed. Acute oral toxicity studies of the starch powder in Swiss Albino Mice showed non-toxic and there were no significant change in body weights, food and water consumption by the animals from all dose groups (50-6400 mg/kg bw). Observations against various physico-chemical parameters and granular morphology were also noticed. The present work substantiates the usefulness of the starch powder isolated from this wild turmeric and supports its nutritional significance and non-toxic effect. This underutilized minor tuber crop is potential in many food and non-food applications based on their physico-chemical characteristics
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