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21.
Hafiz T.Ali MRamzan M Imran Arshad Nicola A.Morley M.Hassan Abbas Mohammad Yusuf Atta Ur Rehman Khalid Mahmood Adnan Ali Nasir Amin MAjaz-un-Nabi 《中国物理 B》2022,31(2):27502-027502
We investigate the impact of Ni insertion on the structural,optical,and magnetic properties of Ba0.8La0.2Fe12-xNixO19hexaferrites(Ni substituted La-BaM hexaferrites).Samples were prepared using the conventional co-precipitation method and sintered at 1000℃for 4 hours to assist the crystallization process.An analysis of the structure of the samples was carried out using an x-ray diffraction(XRD)spectrometer.The M-type hexagonal structure of all the samples was confirmed using XRD spectra.The lattice parameters a and c were found to be in the ranges of 5.8925±0.001 nm–5.8952±0.001 nm and 23.2123±0.001 nm–23.2219±0.001 nm,respectively.The M-type hexagonal nature of the prepared samples was also indicated by the presence of corresponding FT-IR bands and Raman modes in the FT-IR and Raman spectra,respectively.EDX results confirmed the successful synthesis of the samples according to the required stoichiometric ratio.A UV-vis spectrometer was used to record the absorption spectra of the prepared samples in the wavelength range of 200 nm–1100 nm.The optical energy bandgap of the samples was found to be in the range of 1.21 eV–3.39 eV.The M–H loops of the samples were measured at room temperature at an applied magnetic field range of 0 kOe–60 kOe.A high saturation magnetization of 99.92 emu/g was recorded in the sample with x=0 at a microwave operating frequency of 22.2 GHz.This high value of saturation magnetization is due to the substitution of La3+ions at the spin-up(12k,2a,and 2b)sites.The Ni substitution is proven to be a potential candidate for the tuning of the optical and magnetic parameters of M-type hexaferrites.Therefore,we suggest that the prepared samples are suitable for use in magneto-optic applications. 相似文献
22.
Inês R. Ramos Fiona M. Lyng Ihtesham Ur Rehman Basil Sharrack M. Nicola Woodroofe 《应用光谱学评论》2017,52(10):868-882
Spectroscopy techniques are valuable tools in biomedical research and have been used extensively in the study of disease. However, neurological conditions such as multiple sclerosis (MS) have received little attention and the available spectroscopy studies are limited, both in overall numbers of patients studied and the disease samples considered. MS is a complex immune-mediated disease, with variable clinical courses and limited therapeutic options. This review aims to summarize current literature in the area, demonstrating how spectroscopy techniques can provide valuable information to inform and advance research into the most common neurological condition affecting young adults. 相似文献
23.
C. Andreoiu M. Axiotis G. de Angelis J. Ekman C. Fahlander E. Farnea A. Gadea T. Kröll S.M. Lenzi N. Mărginean T. Martinez M.N. Mineva C. Rossi Alvarez D. Rudolph C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):459-462
Excited states in 59Zn were observed for the first time following the fusion-evaporation reaction 24Mg + 40Ca at a beam energy of 60 MeV. The GASP array in conjunction with the ISIS Silicon ball and the NeutronRing allowed for the
detection of γ-rays in coincidence with evaporated light particles. The mirror symmetry of 59Zn and 59Cu is discussed.
Received: 28 May 2002 / Accepted: 10 July 2002 / Published online: 3 December 2002
RID="a"
ID="a"Present address: Oliver Lodge Laboratory, University of Liverpool, P.O. Box 147, Liverpool, L69 7ZE, United Kingdom; e-mail: ca@ns.ph.liv.ac.uk.
RID="b"
ID="b"Present address: Physik-Departament, Technische Universit?t München, D-85748 Garching, Germany.
Communicated by W. Henning 相似文献
24.
S. Torilov S. Thummerer W. von Oertzen Tz Kokalova G. de Angelis H. G. Bohlen A. Tumino M. Axiotis E. Farnea N. Marginean T. Martinez D. R. Napoli M. De Poli S. M. Lenzi C. Ur M. Rousseau P. Papka 《The European Physical Journal A - Hadrons and Nuclei》2004,19(3):307-317
We have studied the reactions
as well as the binary channel
, in order to search for deformed states, which form rotational bands in 40Ca. We observe positive- and negative-parity bands. The negative-parity band is proposed to be a partner of an inversion doublet with the positive-parity states being based on 4p-4h configurations. The properties of the positive-parity states are discussed on the basis of the shell model and the parity doublet on the basis of a cluster model with intrinsic reflection asymmetric shapes.Received: 2 May 2003, Revised: 23 September 2003, Published online: 20 January 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.60.Gx Cluster models 相似文献
25.
Ts Venkova R. M. Lieder W. Gast D. Bazzacco G. de Angelis E. Podsvirova H. M. Jäger L. Mihailescu R. Menegazzo S. Lunardi C. Rossi Alvarez C. Ur T. Martinez M. Axiotis D. Napoli W. Urban T. Rzaca-Urban 《The European Physical Journal A - Hadrons and Nuclei》2003,18(4):577-581
High-spin states in the odd-proton nucleus 173Lu have been populated in a 170Er(7Li,4n) reaction and the emitted
-radiation was detected with the GASP array. The favoured and unfavoured sequences of the
band have been considerably extended. The favoured sequence does not show any indication of a band crossing up to a rotational frequency of
0.45 MeV. This is the largest crossing frequency ever observed for 1/2- [541] bands of odd-proton nuclei with
and
. Previous Cranked Shell Model (CSM) calculations underestimate the crossing frequency by 100 keV.Received: 19 May 2003, Published online: 11 November 2003PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.10.Re Collective levels - 23.20.Lv
transitions and level energies - 27.70. + q
相似文献
26.
P. Mason N. Marginean G. Montagnoli S. Beghini F. Scarlassara E. Farnea C. A. Ur A. Meroni A. M. Stefanini L. Corradi E. Fioretto I. V. Pokrovskiy B. Guiot A. Gadea J. J. Valiente-Dobón F. Della Vedova R. Orlandi E. Sahin D. R. Napoli L. Berti N. Toniolo S. Szilner M. Trotta M. Romoli M. La Commara D. Pierroutsakou M. Sandoli G. Pollarolo G. Benzoni 《The European physical journal. Special topics》2007,150(1):359-361
PRISMA is a magnetic
spectrometer installed at Laboratori Nazionali di Legnaro (Italy)
and designed for A=100–200, E=5–10 MeV-per-nucleon beams, and for
possible use with the proposed radioactive beam facility SPES. The
foremost features of the instrument are presented, along with the
outline of two data analyses exemplifying the effectiveness of
PRISMA-CLARA in studies of reaction
dynamics. 相似文献
27.
N. A. Bulychev V. N. Fomin E. B. Malyukova N. B. Ur’ev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(1):84-88
Regularities of the adsorption of ethylhydroxyethylcellulose (EHEC) hydrophilic polymer on a surface of inorganic pigments
of TiO2 and Fe2O3 were investigated by infrared spectroscopy. It was found that the adsorption interaction between EHEC and a surface of oxides
is accompanied by conformation transformations of the adsorbed molecules of EHEC. The means by which macromolecules bind with
active centers on a surface of metal oxides and the influence of the oxides’ nature on the EHEC macromolecule conformation
transformations determining the structure of the adsorption layer upon adsorption were established. 相似文献
28.
Differential thermal analysis is performed for native human serum albumin, denatured human serum albumin, and their mixtures
with water in the range 80–550 K. The temperatures of phase transitions of the protein are determined, and the effect of water
on these transitions is ascertained. The limit of water solubility in the native protein is estimated from the calorimetry
data on the enthalpy of melting of the excess-water phase. The phase diagram of the albumin-water system is plotted and analyzed
in wide temperature and concentration ranges. 相似文献
29.
Saqlain Abbas Fucai Li Zulkarnain Abbas Taufeeq Ur Rehman Abbasi Xiaotong Tu Riffat Asim Pasha 《声与振动》2021,55(1):1-18
Structural health monitoring (SHM) is recognized as an efficient tool to interpret the reliability of a wide variety of infrastructures. To identify the structural abnormality by utilizing the electromechanical coupling property of piezoelectric transducers, the electromechanical impedance (EMI) approach is preferred. However, in real-time SHM applications, the monitored structure is exposed to several varying environmental and operating conditions (EOCs). The previous study has recognized the temperature variations as one of the serious EOCs that affect the optimal performance of the damage inspection process. In this framework, an experimental setup is developed in current research to identify the presence of fatigue crack in stainless steel (304) beam using EMI approach and estimate the effect of temperature variations on the electrical impedance of the piezoelectric sensors. A regular series of experiments are executed in a controlled temperature environment (25°C–160°C) using 202 V1 Constant Temperature Drying Oven Chamber (Q/TBXR20-2005). It has been observed that the dielectric constant ε33T which is recognized as the temperature-dependent constant of PZT sensor has sufficiently influenced the electrical impedance signature. Moreover, the effective frequency shift (EFS) approach is optimized in term of significant temperature compensation for the current impedance signature of PZT sensor relative to the reference signature at the extended frequency bandwidth of the developed measurement system with better outcomes as compared to the previous literature work. Hence, the current study also deals efficiently with the critical issue of the width of the frequency band for temperature compensation based on the frequency shift in SHM. The results of the experimental study demonstrate that the proposed methodology is qualified for the damage inspection in real-time monitoring applications under the temperature variations. It is capable to exclude one of the major reasons of false fault diagnosis by compensating the consequence of elevated temperature at extended frequency bandwidth in SHM. 相似文献
30.
V. F. Ur’yash V. N. Larina N. Yu. Kokurina N. V. Novoselova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(6):915-921
The heat capacity of cotton microcrystalline cellulose was measured on an adiabatic vacuum calorimeter over the temperature
range 80–330 K, and the differential thermal analysis data on the substance were obtained from 80 to 550 K. The enthalpy of
cellulose interaction with water was measured at 303 K using a differential microcalorimeter. The standard enthalpies of combustion
and formation of microcrystalline cellulose and wood celluloses with different crystallinity indices were determined. The
concentration of saturated water solution in microcrystalline cellulose at 273 K was determined calorimetrically from the
enthalpy of fusion of the excess water phase. 相似文献