scholarly journals Spin Alignment and Collective Moment of Inertia of the Basic Rotational Band in the Cranking Model

1982 ◽  
Vol 68 (3) ◽  
pp. 808-819
Author(s):  
Y. Tanaka
2011 ◽  
Vol 20 (04) ◽  
pp. 759-764 ◽  
Author(s):  
MATKO MILIN

The experimental evidence for existence of cluster and molecular states in 10 Be , 10 B and 10 C is presented in details. For the most studied of the three, 10 Be , a rotational band have recently been firmly identified, with states having rather large moment of inertia. For the isobaric analogue states in 10 B first experimental results have been obtained and presented; some simple predictions for the 10 C nucleus are also given.


2008 ◽  
Vol 17 (10) ◽  
pp. 2345-2348 ◽  
Author(s):  
MILIVOJ UROIĆ ◽  
DURO MILJANIĆ ◽  
SAŠA BLAGUS ◽  
MLADEN BOGOVAC ◽  
NATKO SKUKAN ◽  
...  

Isobaric analogues of three states in 10 Be forming a rotational band with high moment of inertia are expected in 10 B and 10 C . This article reports a measurement of excitation spectrum in 10 B obtained through 11 B (3 He ,α)10 B reaction. A T = 1 state is found on 11.3 MeV excitation energy. It is a possible candidate for the 4+ state of the analogue rotation band.


Pramana ◽  
2015 ◽  
Vol 86 (1) ◽  
pp. 185-190 ◽  
Author(s):  
V S UMA ◽  
AlPANA GOEL ◽  
ARCHANA YADAV ◽  
A K JAIN

1982 ◽  
Author(s):  
Carol Zahner ◽  
M. Stephen Kaminaka

1971 ◽  
Vol 32 (C6) ◽  
pp. C6-289-C6-290
Author(s):  
P. THIEBERGER ◽  
A. W. SUNYAR ◽  
P. C. ROGERS ◽  
N. LARK ◽  
O. C. KISTNER ◽  
...  
Keyword(s):  

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Joachim Landers ◽  
Soma Salamon ◽  
Samira Webers ◽  
Heiko Wende

Abstract Mössbauer spectroscopy is a well-known technique to study complex magnetic structures, due to its sensitivity to electronic and magnetic interactions of the probed nucleus with its electronic surrounding. It has also been applied to the emerging fields of magnetic hybrid materials as well as to ferrofluids, as information on the magnetic alignment and the velocity of the probed nucleus, i.e. of the particle it is embedded in, can be inferred from the spectra in addition to the above-mentioned quantities. Considering the wide range of preparation methods and sample properties, including fluids, particle powders, sintered pellets, polymer matrices and viscoelastic hydrogels, a considerable advantage of Mössbauer spectroscopy is the usage of γ-photons. This allows measurements on opaque samples, for which optical experiments are usually not feasible, also making the technique relatively independent of specific sample geometries or preparation. Using iron oxide nanoparticles in glycerol solution as an exemplary material here, the variety of system parameters simultaneously accessible via Mössbauer spectroscopy can be demonstrated: Spectra recorded for particles of different sizes provided information on the particles’ Brownian dynamics, including the effect of the shell thickness on their hydrodynamic diameter, the presence (or absence) and ballpark frequency of Néel superspin relaxation as well as the particles’ average magnetic orientation in external magnetic fields. For single-core particles, this resulted in the observation of standard Langevin-type alignment behavior. Mössbauer spectra additionally provide information on the absolute degree of spin alignment, also allowing the determination of the degree of surface spin canting, which limits the maximum magnetization of ferrofluid samples. Analyzing the alignment behavior of agglomerated particles for comparison, we found a completely different trend, in which spin alignment was further hindered by the competition of easy magnetic directions. More complex particle dynamics are observed when going from ferrofluids to hybrid materials, where the particle mobility and alignability depends not only on the particles’ shape and material, but also on the matrices’ inner structure and the acting force-transfer mechanism between particles and the surrounding medium. In ferrohydrogels for example, particle mobility in terms of Mössbauer spectroscopy was probed for different crosslinker concentrations, resulting in widely different mesh-sizes of the polymer network and different degrees of freedom. While a decrease in particle dynamics is clearly visible in Mössbauer spectroscopy upon rising crosslinker density, complementary AC-susceptometry experiments indicated no Brownian motion on the expected timescales. This apparent contradiction could, however, be explained by the different timescales of the experiments, probing either the relatively free Brownian motion on ultrashort timescales or the more bound state preventing extensive particle motion by interaction with the trapping mesh walls in the millisecond regime. However, it should also be considered that the effect of the surroundings on particle rotation in AC-susceptometry may also differ from the variation in translational motion, probed by Mössbauer spectroscopy. Being sensitive mainly to translational motion also results in a wide range of particles to be accessible for studies via Mössbauer spectroscopy, including larger agglomerates embedded in polymers, intended for remote-controlled heating. Despite the agglomerates’ wide distribution in effective diameters, information on particle motion was found to be in good agreement with AC-susceptometry experiments at ultralow frequencies in and above the polymer melting region, while additionally giving insight into Néel relaxation of the individual nanoparticles and their magnetic structure.


Author(s):  
Mustafa Babagiray ◽  
Hamit Solmaz ◽  
Duygu İpci ◽  
Fatih Aksoy

In this study, a dynamic model of a single-cylinder four-stroke diesel engine has been created, and the crankshaft speed fluctuations have been simulated and validated. The dynamic model of the engine consists of the motion equations of the piston, conrod, and crankshaft. Conrod motion was modeled by two translational and one angular motion equations, by considering the kinetic energy resulted from the mass moment of inertia and conrod mass. Motion equations involve in-cylinder gas pressure forces, hydrodynamic and dry friction, mass inertia moments of moving parts, starter moment, and external load moment. The In-cylinder pressure profile used in the model was obtained experimentally to increase the accuracy of the model. Pressure profiles were expressed mathematically using the Fourier series. The motion equations were solved by using the Taylor series method. The solution of the mathematical model was performed by coding in the MATLAB interface. Cyclic speed fluctuations obtained from the model were compared with experimental results and found compitable. A validated model was used to analyze the effects of in-cylinder pressure, mass moment of inertia of crankshaft and connecting rod, friction, and piston mass. In experiments for 1500, 1800, 2400, and 2700 rpm engine speeds, crankshaft speed fluctuations were observed as 12.84%, 8.04%, 5.02%, and 4.44%, respectively. In simulations performed for the same speeds, crankshaft speed fluctuations were calculated as 10.45%, 7.56%, 4.49%, and 3.65%. Besides, it was observed that the speed fluctuations decreased as the average crankshaft speed value increased. In the simulation for 157.07, 188.49, 219.91, 251.32, and 282.74 rad/s crankshaft speeds, crankshaft speed fluctuations occurred at rates of 10.45%, 7.56%, 5.84%, 4.49%, and 3.65%, respectively. The effective engine power was achieved as 5.25 kW at an average crankshaft angular speed of 219.91 rad/s. The power of friction loss in the engine was determined as 0.68 kW.


Author(s):  
Chuanwen Zhang ◽  
Guangxu Zhou ◽  
Ting Yang ◽  
Ningran Song ◽  
Xinli Wang ◽  
...  

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