THE SYSTEMATIC BEHAVIOR IN THE FRAGMENTS OF THE CALCIUM ISOTOPES PROJECTILE FRAGMENTATION

2010 ◽  
Vol 19 (08n09) ◽  
pp. 1545-1552 ◽  
Author(s):  
CHUN-WANG MA ◽  
HUI-LING WEI ◽  
YU-QI LI
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Linear Correlation ◽  
Binding Energies ◽  
Projectile Fragmentation ◽  
Skin Thickness ◽  
Neutron Skin ◽  
Good Linear ◽  
Calcium Isotopes ◽  
Good Linear Correlation

We have calculated the cross sections of the fragments produced in the projectile fragmentation of the even 36–52 Ca isotopes using the statistical abrasion-ablation model. The isospin effect in the projectile fragmentation are studied by investigating the peak positions and the widths of the fragment isotopic cross section distributions. The peak positions of the fragments isotopic cross section distributions have good linear correlation to the Z of the fragments and the correlations are fitted using the linear function. The correlations between slopes b and the binding energies of the neutron ( S n) of the projectile nuclei, the differences between the binding energies of the neutron and proton( S n- S p) of the projectile nuclei and the neutron-skin thickness (δnp) are studied. It is found that b and δnp has a good linear correlation for the neutron-rich projectile nuclei.

Formation of α clusters in dilute neutron-rich matter

Science ◽  
2021 ◽  
Vol 371 (6526) ◽  
pp. 260-264 ◽  
Author(s):  
Junki Tanaka ◽  
Zaihong Yang ◽  
Stefan Typel ◽  
Satoshi Adachi ◽  
Shiwei Bai ◽  
...  
Keyword(s):  
Cross Sections ◽  
Cluster Formation ◽  
Reaction Cross ◽  
Skin Thickness ◽  
Neutron Skin ◽  
Heavy Nuclei ◽  
Α Decay ◽  
Neutron Skin Thickness ◽  
Reaction Cross Sections ◽  
Α Particles

The surface of neutron-rich heavy nuclei, with a neutron skin created by excess neutrons, provides an important terrestrial model system to study dilute neutron-rich matter. By using quasi-free α cluster–knockout reactions, we obtained direct experimental evidence for the formation of α clusters at the surface of neutron-rich tin isotopes. The observed monotonous decrease of the reaction cross sections with increasing mass number, in excellent agreement with the theoretical prediction, implies a tight interplay between α-cluster formation and the neutron skin. This result, in turn, calls for a revision of the correlation between the neutron-skin thickness and the density dependence of the symmetry energy, which is essential for understanding neutron stars. Our result also provides a natural explanation for the origin of α particles in α decay.

scholarly journals Quantifying Mold Biomass on Gypsum Board: Comparison of Ergosterol and Beta-N-Acetylhexosaminidase as Mold Biomass Parameters

2003 ◽  
Vol 69 (7) ◽  
pp. 3996-3998 ◽  
Author(s):  
M. Reeslev ◽  
M. Miller ◽  
K. F. Nielsen
Keyword(s):  
Stationary Phase ◽  
Linear Correlation ◽  
Stachybotrys Chartarum ◽  
Gypsum Board ◽  
Biomass Density ◽  
Activity Data ◽  
Good Linear ◽  
Ergosterol Content ◽  
Good Linear Correlation

ABSTRACT Two mold species, Stachybotrys chartarum and Aspergillus versicolor, were inoculated onto agar overlaid with cellophane, allowing determination of a direct measurement of biomass density by weighing. Biomass density, ergosterol content, and beta-N-acetylhexosaminidase (3.2.1.52) activity were monitored from inoculation to stationary phase. Regression analysis showed a good linear correlation to biomass density for both ergosterol content and beta-N-acetylhexosaminidase activity. The same two mold species were inoculated onto wallpapered gypsum board, from which a direct biomass measurement was not possible. Growth was measured as an increase in ergosterol content and beta-N-acetylhexosaminidase activity. A good linear correlation was seen between ergosterol content and beta-N-acetylhexosaminidase activity. From the experiments performed on agar medium, conversion factors (CFs) for estimating biomass density from ergosterol content and beta-N-acetylhexosaminidase activity were determined. The CFs were used to estimate the biomass density of the molds grown on gypsum board. The biomass densities estimated from ergosterol content and beta-N-acetylhexosaminidase activity data gave similar results, showing significantly slower growth and lower stationary-phase biomass density on gypsum board than on agar.

Evaluation of Natural Rubber from Clones of Hevea Brasiliensis

2002 ◽  
Vol 75 (1) ◽  
pp. 171-177 ◽  
Author(s):  
Mariselma Ferreira ◽  
Rogério M. B. Moreno ◽  
Paulo S. Gonçalves ◽  
Luiz H. C. Mattoso
Keyword(s):  
Natural Rubber ◽  
Linear Correlation ◽  
Hevea Brasiliensis ◽  
Cold Season ◽  
The State ◽  
Rubber Content ◽  
Good Linear ◽  
Mooney Viscosity ◽  
In The Beginning ◽  
Good Linear Correlation

Abstract The latex and natural rubber from rubber trees [Hevea brasiliensis (Willd. exAdr. de Juss.) Muell. Arg.] from clones (RRIM 600, IAN 873, GT 1 and PB 252) recommended to the state of São Paulo, Brazil, were studied in three different tapping systems. The parameters studied were dry rubber content (DRC), percentages of ash and of nitrogen, Wallace Plasticity (P0) and Mooney Viscosity (VR). The rubber properties vary considerably as a function of clone type, tapping method and season of the year. DRC tends to decrease in the beginning of the dry, cold season (May and June), whereas both nitrogen % and ash % increase in the same period. A good linear correlation was obtained for P0 and VR. The highest P0 and VR were obtained for RRIM 600.

Effect of Limestone Powder on Autogenous Shrinkage of Concrete

2011 ◽  
Vol 88-89 ◽  
pp. 767-771
Author(s):  
Bin Wang ◽  
You Ping Ding ◽  
Jing Gao ◽  
Jin Fang Sun ◽  
Miao Miao Cui ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Linear Correlation ◽  
Autogenous Shrinkage ◽  
Limestone Powder ◽  
Subsequent Reduction ◽  
Reduction Stage ◽  
Good Linear ◽  
Good Linear Correlation

The effect law and mechanism of limestone powder on autogenous shrinkage of concrete was studied. The results indicate that limestone powder accelerates autogenous shrinkage speed of concrete on which effect of fineness is little, and limestone powder reduces autogenous shrinkage which decreases with the increase of fineness. The change law of autogenous shrinkage of concrete is consistent with that of chemically combined water of paste. Autogenous shrinkage of concrete is also divided into 2 stages according to the initial vapor saturated stage and subsequent reduction stage of interior relative humidity, with both showing a good linear correlation at each stage.

scholarly journals Linear correlation between Debye temperature and lattice thermal conductivity in II-VI and III-V semiconductors

2015 ◽  
Vol 3 (2) ◽  
pp. 216 ◽  
Author(s):  
Salah Daoud
Keyword(s):  
Thermal Conductivity ◽  
Simple Model ◽  
Debye Temperature ◽  
Rock Salt ◽  
Linear Correlation ◽  
Lattice Thermal Conductivity ◽  
Empirical Relationship ◽  
Average Percentage ◽  
Good Linear ◽  
Good Linear Correlation

<p>A simple linear empirical relationship between high intrinsic lattice thermal conductivity K, and Debye temperature θ<em><sub>a</sub></em> is suggested from data on high intrinsic lattice thermal conductivity K, and Debye temperature θ<em><sub>a</sub></em> for some selected II-VI and III-V cubic zincblende type, and I-VII and II-VI rock-salt type binary semiconductors. A good linear correlation between Debye temperature and the high intrinsic lattice thermal conductivity was obtained. The minimum average percentage deviations in the present approach reveal that our simple model prove its identity and soundness compared to those of other author relations.</p>

ISOSPIN EFFECT AND ISOSCALING PHENOMENON IN PROJECTILE FRAGMENTATION

2008 ◽  
Vol 17 (09) ◽  
pp. 1669-1680 ◽  
Author(s):  
C. W. MA ◽  
Y. FU ◽  
D. Q. FANG ◽  
Y. G. MA ◽  
X. Z. CAI ◽  
...  
Keyword(s):  
Excitation Energy ◽  
Projectile Fragmentation ◽  
Skin Thickness ◽  
Neutron Density ◽  
Neutron Skin ◽  
Density Distributions ◽  
Neutron Rich Nucleus ◽  
Neutron Skin Thickness ◽  
Neutron Density Distribution ◽  
The Relationship

We have studied the isospin effect and isoscaling behavior in projectile fragmentation using a modified statistical abrasion-ablation (SAA) model. The relationship between neutron skin thickness (δnp) and neutron abrasion cross section (σ nabr ) has also been investigated. We find the normalized peak differences and reduced isoscaling parameters decrease with (Z proj - Z)/Z proj or the excitation energy per nucleon and have no significant dependence on the size of the reaction systems. The excitation energy dependence of the symmetry energy coefficients are tentatively extracted from α and β. Assuming Fermi-type density distributions for proton and neutron and introducing a parameter to adjust the diffuseness of the neutron density distribution for neutron-rich nucleus, δnp and σ nabr for neutron-rich nucleus were found to have a linear correlation. It is suggested that σ nabr could be used as an observable to extract the neutron skin thickness for neutron-rich nucleus.

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