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Co-granulation of teawaste with limestone was investigated using sodium-based lignosulfonate as a binder. A quality by design (QbD) approach was employed to formulate models for predicting the granule mean size, granule strength, limestone and binder uniformity from the process, and formulation variables. The results showed that teawaste volume fraction and liquid to solid ratio had a greater effect than other variables on granule mean size. Increasing teawaste in a binary mixture had a negative effect on granule mean size but positive effect on granule tensile strength. Limestone and binder uniformity could be increased by using higher impeller speed. DEM simulation showed that the impeller speed had a significant effect on the mixing quality and light particle fraction could significantly affect the fluctuation of the mixing index at the equilibrium stage. X-ray micro-computer tomography was applied as a technique to see the internal structure of the granules produced.

Factors that influence the accuracy of the experimental determination of small velocities (on a level of 1 cm/s and below) of a light particle (weighing 10 mg and less) suspended by a thin elastic rod or thread have been considered. The influence of a finite mass and bending elasticity of the rod on the natural frequency of pendulum oscillations is theoretically analyzed. It is established that the main factor affecting the natural frequency is the bending elasticity of suspension, whereas the influence of a finite mass of the rod can be reduced to a minimum. An exact analytical expression for the natural frequency of a real pendulum is obtained for an arbitrary bending elasticity of the light rod.

Signatures of large few-body systems were recently observed in experiments with ultracold gases. This paper presents a brief introductory review of related theoretical concepts and recent experimental advances.

In the paper the registration sensitivity of light swift charged projectiles in Solid State Nuclear Track Detectors (SSNTD) of type CR-39 is investigated. Comparing experimental data and their interpretation in terms of empirical and semi-empirical models, the influence of physics aspects of particle transport in solids on the registration sensitivity is studied. Taking into account the energy loss along the particle trajectory by particle–matter interaction the basic properties of the sensitivity functions for registration of protons, deuterons and ions of 4He, 7Li, 11B, 12C, 14N and 16O are described. However, a unique interpretation in terms of physics of particle penetration into a solid cannot be achieved. Deviations from fundamental physics are highlighted and discussed.

Exact analytical solutions of three- and four-body systems made of one light particle and other heavy particles have been obtained in the model of Born–Oppenheimer approximation with two-body separable interactions. In the case of neutron scattering on a subsystem of few fixed nuclei the appearance of new resonance quantum states has been shown as well as their dependence on distances between heavy nuclei. The applications of new phenomena to overdense stars radiation are considered.

An approach to solving scattering problems in three-body systems for cases where the mass of one of the particles is extremely small in relation to the masses of the other two particles and where the pair potentials of interaction between the particles involved are separable is developed. Exact analytic solutions to such model problems are found for the scattering of a light particle on two fixed centers and on two interacting heavy particles. It is shown that new resonances and a dynamical resonance enhancement may appear in a three-body system.

Energy dependence of nuclear shadowing and nuclear absorption is discussed in the framework of the Glauber–Gribov model and the AGK cutting rules. We calculate gluon shadowing using recent data on diffractive structure functions from HERA. Phenomenological implications for light particle production at SPS and RHIC are described and compared to charged particle production at mid- and forward rapidities. Comparison of the suppression at these energies leaves nevertheless little room for additional suppression phenomena.

SDRAMs have been exposed to protons, neutrons, alpha particles, heavy ions and Co60 irradiations. Numerous cells exhibit large data retention time degradation that are attributed to single interactions. The physical process leading to the degradation is discussed. The annealing behavior and leakage current order of magnitude are compatible with the properties, stability and emission rate of clusters of defects in the silicon

The aim of this paper is to study the effect of curvature and compressibility energies on the deexcitation process of hot nuclei within a modified version of the combined dynamical statistical model. The prescission light particle multiplicities are chosen as the probe. The calculation results show that the multiplicity calculated with the modified model is closer to the data compared with the original one, especially for the neutron-deficient systems. Our results also show that the multiplicity decreases as the coordinate dependence of the employed level-density parameter strengthens. Therefore, this coordinate dependence is taken into consideration in investigating the deformation dependence of nuclear friction. With a physically reasonable correction factor for the emission barrier, better agreement with data can be acquired for the light charged particle multiplicities. The physics of the compressibility energy considered in this work is discussed.

Comparative analysis of the experimental data on the induced fission lifetimes for the Pb-like and U-like nuclei produced in the 208Pb + 28Si and 238U + 28Si reactions obtained by the crystal blocking technique was performed. Analysis was produced within the dynamical approach based on Langevin equations taking into account light particle emission from the hot fissioning system. Description of the analyzed energy dependence of the time values for U-like nuclei allows us to obtain information on the magnitude of nuclear viscosity.

The authors review what has been learned concerning the electrical and annealing properties of point defects in high-energy electron or proton irradiated Si from deep level transient spectroscopy (DLTS). The authors have focused mainly on the properties of electron traps, and to a lesser extent on the properties of hole traps. In addition to an in-depth discussion of hydrogen-related defects in Si, this review article provides a brief tutorial on ion-solid interactions and the theory underlying DLTS. The authors also provide a few examples of the power of high resolution Laplace DLTS in analyzing radiation induced defects. The collection of results gathered in this article may provide the fundamental information for successful defect engineering in light-particle irradiated Si.

Dilute laminar expanded polystyrene particle–oil flows in a vertical pipe were studied using a three-dimensional particle image tracking (PIT) method. The particle volume fraction profiles and other flow properties for the upward fully developed flows were measured. The experimental results showed that the particles in both the large and small particle and oil flows have a wall-peaked distribution similar to those of near-spherical bubbles in laminar bubbly flows. The ordered particle distribution structure consisting of particle clusters and its transition to disordered flow structures were observed. Comparisons between the bubble and particle volume fraction profiles indicate that the major difference of two-phase flow properties may result from bubble deformation.

We consider the motion of a light particle when the force field is perturbed by a small nose. If a certain relation between the mass of the particle and the noise intensity holds, the motion of the particle will be close to periodic oscillations or to a stable equilibrium which do not exist without the noise. We study various classes of random perturbations. In particular, we consider the question of computer simulation of these effects and calculate the correction term which appears when the Gaussian perturbations are replaced by the simple random walk. These are the stochastic-resonance-type effects, and their mathematical description is based on the large deviation theory.

Conservation laws that are linear with respect to the number of particles are constructed for classical and quantum Hamiltonians. A class of relaxation models generalizing discrete models of the Boltzmann equation are also considered. Conservation laws are written for these models in the same form as for the Hamiltonians.

A new setup is proposed aimed at the study of single particle structures of nuclei far from stability by nucleon transfer reactions in inverse kinematics using radioactive ion beams obtained from REX-ISOLDE. The setup combines particle and γ -ray detection using the MINIBALL array and was designed to achieve a high particle efficiency by covering a large angular range while retaining the high γ -ray efficiency of the MINIBALL setup. All particle detectors are segmented and/or position-sensitive silicon detectors, for forward angles built as Δ E − E rest telescopes for light particle identification. As a first experiment with this new setup, the d(30Mg, 31Mg)p reaction at 3 MeV/u will be performed in 2007.

A simple derivation of the formula for the flux of light at a point from cosmic light sources is given. Both the obscuration of distant sources by nearby ones and the expansion of the universe are taken into account. The explanation of the dark night sky is mainly that the distance travelled by a light particle is much smaller than the mean free path for a photon. Both the obscuration and the expansion are relatively unimportant. We live in a young universe with little energy. Sammendrag. En enkel utledning av formelen for lysfluks i et punkt fra de kosmiske lyskilder blir gitt. B de at de nae rliggende lyskilder vil skygge for de fjerne lyskilder og universets ekspansjon blir tatt i betraktning. Forklaringen pa den morke nattehimmelen er i hovedsak at avstanden som en lyspartikkel har beveget seg, er mye mindre enn midlere fri veilengde for et foton. Ba de skygge-effekten og ekspansjonen er noksa lite viktige. Vi lever i et ungt univers med lite energi.

The theoretical expression of the double differential cross-section for the sequential three-body reaction A(a, b)B(c)C is derived in the hypothesis that the nucleus B is excited to levels that lie in the continuum region. A theoretical approach for the angular correlation between light particles and reaction fragments emitted in peripheral heavy-ion collisions is presented. In particular it is shown that also in the hypothesis of sequential process there is an important nonequilibrium component in the particle emission and that information on the polarization effects of the reaction fragment B can be obtained from investigation of the in-plane angular correlation pattern around the forward angles. A closed-form expression for the in-plane differential multiplicity is discussed and applied to the in-plane C-α differential multiplicities for the deeply inelastic collisions16O(101 MeV)+48Ti and16O(96 MeV)+58Ni, respectively.

In this paper we study the impact-parameter model for the scattering of a light particle by two heavy ones in the case when the coupling constants of the potentials acting on the light particle due to the presence of the two heavy ones are the same. We study the asymptotic behavior of the transition probability when the relative velocity of the heavy particles goes to zero. We show that the probability of a transition can be arbitrarily close to the one of no transition.

In many applications, double-differential (energy and angle) secondary light particle production cross sections must be known for ion energies from tens of MeV/nucleon to tens of GeV/nucleon. Incorporating high energy light particle spectral and angular distribution cross section databases in the transport codes enable them to transport nearly any radiation field, in three dimensions, that humans and instruments might be exposed to in space, near accelerators or during charged particle radiotherapy. In this work a thermodynamics coalescence model is used to estimate the coalescence and emitting source radii for both symmetric and asymmetric heavy ion collision systems.

We use Monte Carlo reaction simulation calculations to reassess several studies of fissionfragment angular correlations. The reactions chosen are 15–30 MeV/nucleon14N +238U and 14.6 MeV/nucleon20Ne +197Au. Reanalysis by means of these stimulations leads to much lower limits than originally reported for the fraction of complete fusion. We infer that at these energies the probability is very large for the direct emission of at least one light particle prior to fission. This implies that the distinction between “complete fusion” and “incomplete fusion” has become blurred beyond meaningful distinction.

Simple theoretical expressions are presented for the equilibrium and pre-equilibrium parts of the heavy-ion-light-particle angular correlation for a sequential three-body reaction X(a,b)Y(c)Z under the hypothesis that the nucleus Y is excited to levels that lie in the continuum region. Semi-classical formulae for the equilibrated and nonequilibrated parts of the in-plane b-c differential multiplicity are given; in particular, the nonequilibrated part is explained as emission of particles c from the nuclear surface of Y. It is also outlined how a crude estimate of the decay times can be obtained.

We derive a master equation to describe the time evolution of the intrinsic state in heavy-ion collisions. It takes into account the energy supply from the relative motion due to the one-body dissipation mechanism, and the equilibration process and the particle emission due to the two-body residual interaction. We then calculate the energy spectrum and the angular distribution of the emitted protons in14N,16O andα induced reactions for various targets and incident energies. The angular distribution is calculated based on a simple phase-space consideration. The numerical results agree very well with experimental data.

A simple theoretical approach for the nonequilibrium component of the angular correlation between light particles and projectilelike fragments emitted in peripheral heavy-ion collisions is discussed. In particular it is emphasized that many characteristic features of the angular correlation pattern in general do not imply that the fast light particles emerge from the contact zone between the two colliding nuclei. Besides, following a semi-classical picture, it is outlined how a relationship between the nonequilibrium decay time and the light-particle emission angle may be assumed.

Two direct mechanisms are considered for the heavy ion collisions which lead to fast α-particle emission: α-particle knock on by the incident ion and heavy fragment stripping of this ion. It is demonstrated that stripping mechanism allows to reproduce all the experimental characteristic features of the process except the cross-section dependence on α-particle separation energy in the target. Knock on process reproduces this feature as well. It is pointed that the analysis of experimental data on the hard part of α-particle spectrum allows to gain a unique information on the properties of the strongly rotating nuclei produced in these reactions.

By means of residual electrical resistivity measurements, low temperature neutron-irradiation damage was investigated in Al and Pt which were doped with various defects. It was found that the damage rate of Al at 1.8 °K was almost unchanged by the addition of 0.5% Mg, and furthermore, that the presence of this impurity suppressed the damage rate enhancement normally caused by deformation of high purity Al. Similar results were obtained for IS Al, which contains 0.35% Fe + Si. These results indicate that the effect of channeling on the damage rate of Al is small. The damage rate of Pt was affected little by deformation, but was enhanced approximately 12% for samples containing ≈ 10−4 quenched-in vacancies. The stage I recovery of Pt was increased 30 to 50% by deformation or by quenched-in vacancies. The results were compared with those of other investigations. It was concluded that most of the differences between heavy and light particle irradiations were caused by the greater importance of long-range focused collision sequences in the former. Mit Hilfe von elektrischen Restwiderstandsmessungen wird Strahlungsdamage durch Neutronen an verschieden dotierten Al- und Pt-Proben bei niedrigen Temperaturen untersucht. Die Schadigungsrate von Al bleibt durch den Zusatz von 0.5% Mg bei 1.8 °K nahezu unverandert. Diese Verunreinigung unterdruckt auserdem die durch Verformung von hochreinem Al normalerweise vergroserte Schadigungsrate. Ahnliche Ergebnisse werden an IS AI (Verunreinigungen 0.35% Fe + Si) erhalten. Diese Ergebnisse zeigen, das Channeling die Schadigungsrate von Al wenig beeinflust. Die Schadigungsrate von Pt wird durch Verformung wenig geandert, doch wird eine Zunahme von ungefahr 12% fur Proben mit ≈ 10−4 abgeschreckten Leerstellen beobachtet. Die Stufe-I-Erholung von Pt wird durch Verformen oder Abschrecken um 30 bis 50% vergrosert. Die Ergebnisse werden mit denen anderer Untersuchungen verglichen. Danach scheinen die wesentlichen sich ergebenden Unterschiede in der Bestrahlung mit leichten oder schweren Teilchen darin zu liegen, das weitreichende fokussierende Stosfolgen eine groosere Bedeutung fur die Bestrahlung mit schweren Teilchen besitzen.

SynopsisA previous discussion (Feather 1969a) of the energetics of the separation of an α-particle in the ternary fission of an (e, e) nucleus is generalised to cover the case of a light particle of arbitrary mass and charge separating from a fissioning nucleus the nucleon-parity type of which may be any one of the four possible types. A ‘profitability index’ is defined in terms of which certain broad differences in the light-particle spectra from different types of fissioning nucleus are predicted, and the results of detailed calculations of the minimum energy expense of separation are given for various light particles emitted in the fission of and, for comparison, for an α-particle emitted in the fission of , an (o, o) nucleus.

The relaxation of a Lorentz gas (dilute light particle subsystem in a heavy particle heat bath) has been studied for a repulsive r—s central force law interaction between the light and heavy particles. The Fokker—Planck equation for the velocity distribution functions of the light particle subsystem has been solved numerically for s=5, 9, 13, 21, and ∞ for various initial conditions. The dependence of the rate of relaxation and of the form of the time‐dependent velocity distribution function on the force law parameter s is discussed in light of the above results.

A three-body model suitable for the investigation of compound, quasi-compound and potential resonances is presented. The exact solution of the model based on Faddeev's method is discussed. Numerical calculations are performed for negative total energy.

SynopsisThe analysis of the previous paper is extended, taking account of the spread of Q-values in the disintegration 5He→He+1n. Conclusions in respect of the experimental results of Cheifetz et al. (1972) remain essentially unchanged.

If dark matter has a finite size that is larger than its Compton wavelength, the corresponding self-interaction cross section decreases with the velocity. We investigate the implications of this Puffy Dark Matter for addressing the small-scale problems of the $\Lambda$CDM model. In particular, we show that the way the non-relativistic cross section varies with the velocity is largely independent of the dark matter internal structure when the range of the mediating force is very short. We present an explicit example in the context of a QCD-like theory of dark matter and show that low-threshold direct detection experiments have the potential to probe Puffy Dark Matter., Comment: 7 pages, 4 figures. Version accepted for publication in PRL