Influence of Different Types of Emulsifiers on Properties of Emulsified Asphalt Binder and Its Evaporation Residue by Molecular Dynamics Simulation

There is an important role in the properties of emulsified asphalt binder and its evaporation residue about emulsifier, which has been confirmed by experiment and chemical tests. However, there is little research about the emulsifier at microperspective. Therefore, the influence of two kinds of emulsifiers, a typical cationic emulsifier (dodecyl benzene sulfonate) and a typical anionic emulsifier (dodecyl primary amine), on technical properties of emulsified asphalt binder and its evaporation residues such as store stability, workability, breaking behavior, and mechanical properties are investigated using a microapproach. Results show that there is an effective role in the storage stability, workability, and demulsification of emulsified asphalt binder about cationic emulsifier compared with anionic emulsifier. The anionic emulsifier makes the density of evaporation residue larger. However, the mechanical properties of anionic emulsified asphalt evaporation residue are conversely smaller compared with the cationic emulsified asphalt evaporation residue. The adhesion behavior results have confirmed that the anionic emulsified asphalt evaporation residue has a negative adhesion with aggregate due to its anion. The mechanism of the different emulsifiers on asphalt binders and their evaporation residue is explored at a microscale to help us to understand emulsified asphalt binder and its evaporation residue more in depth.

Measuring precise fusion cross sections using an 8T superconducting solenoid

A novel fusion-evaporation residue separator based on a gas-filled superconducting solenoid has been developed at the Australian National University. Though the transmission efficiency of the solenoid is very high, precision cross sections measurements require this efficiency to be accurately known and vitally, requires knowledge of the angular distribution of the evaporation residues. We have developed a method to deduce the angular distribution of the evaporation residues from the laboratory-frame velocity distribution of the evaporation residues transmitted by the solenoid. The method will be discussed, focusing on benchmarking examples for 34S+89Y, where the angular distributions have been independently measured using a velocity filter (A. Mukherjee et al., Phys. Rev. C. 66, 034607 (2002)) . The establishment of this method now allows the novel solenoidal separator to be used to obtain reliable, precise fusion cross-sections.

Investigation of breakup fusion in 16O + 124Sn system and its correlation with various entrance channel parameters

Forward recoil range distribution of evaporation residues (ERs) populated through complete fusion (CF) and incomplete fusion (ICF) dynamics in [Formula: see text]O + [Formula: see text]Sn system have been measured. Different full and partial linear momentum transfer components have been observed. The results indicate the occurrence of ICF involving break-up of [Formula: see text]O into 4He + [Formula: see text]C and 8Be + 8Be. However, the present data shows that the ERs are populated through both CF and ICF. A systematic study was performed which shows that the ICF fraction rises exponentially with the established entrance channel parameters and their various combinations. Moreover, these present results clearly show that [Formula: see text] is able to explain the ICF dynamics more conclusively than combined parameter [Formula: see text] for the systems having spherical or slightly deformed target. Further, the dependence of ICF dynamics on target structure has also been studied through a new parameter [Formula: see text] of the target. The parameter [Formula: see text] is directly associated with the target structure and has been found more effective and sensitive than existing parameters to investigate the target structure effect on ICF dynamics. Thus, the present observations suggest that [Formula: see text] ratio of the target should also be considered as an important entrance channel parameter which strongly affects the ICF dynamics.

Fusion probability of massive nuclei in reactions leading to heavy composite nuclear systems

Reactions between massive nuclei show a considerable reduction in fusion-evaporation cross-sections at the Coulomb barrier according to the comparison of experimental values with those calculated by barrier passing (BP) and statistical model (SM) approximations. Reduced fusion cross-sections corresponding to fusion probability PCN<1 are accompanied by a high probability of deep-inelastic and quasi-fission processes arising on the way to fusion. At the same time, the excitation functions for evaporation residues (ERs) obtained in very mass-asymmetric projectile-target combinations are well described in the framework of the BP model (assuming PCN=1) and SM approximations. In the framework of SM, the survivability of produced heavy nuclei can be described with the use of adjusted macroscopic fission barriers. Fusion suppression appears in less asymmetric combinations, for which PCN values can be estimated using survivability obtained for very asymmetric ones leading to the same CN. An attempt was made to systemize the PCN data derived from different projectile-target combinations leading to ERs in the range from Pb to the most heavies, which are compared withPCN values obtained in fission experiments.