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The convective air-drying of two chestnut varieties was evaluated in a laboratory drying oven, at different drying air temperatures (40, 50, 60 and 70°C) and airflow velocities of 2.80 m s -1 . The drying kinetics were compared and the effect of different air-drying temperatures on colour stability, effective diffusivity and starch digestibility was analysed. The two varieties of chestnut used in this study were of the type Castanea sativa (Istrian marron and Italian chestnut). The kinetic equations were estimated using an exponential mathematical model (Page). The results of the estimation have exhibited correspondence to the experimental results. The rate constants, k and n, of the exponential and Page's model for thin-layer drying were established by regression analysis of the experimental data which were found to be affected by drying air temperature. It can be seen that a good agreement between the experimental data and the chosen mathematical model (Page's) exists, which is confirmed by high values of correlation coefficient (0.99) in all run. The influence of temperature on the drying process is an important aspect and should be taken into consideration when choosing the optimal operation conditions. Results show that certain temperatures had a significant effect on the drying rates of chestnut. The drying air temperature significantly influenced the total drying time, which is strongly related to the total energy requirement for drying. The values of effective diffusivity were found to vary in the range of 1,64·10 -9 to 7,88·10 -9 m 2 s -1 for Istrian marron samples and in the range of 8,65·10 -10 to 4,40·10 -9 m 2 s -1 for Italian chestnut samples. Colour change of both varieties was generally increased with the increase of the drying temperature, with the exception of Istrian marron, where colour change was larger after drying at 50°C than after drying at 60°C (probably due to longer exposure to elevated temperature). Digestibility of starch, determined by AOAC 2002.02 method, was increased by drying for both chestnut varieties (Istrian marron and Italian chestnut).

The processes of production of heavy fragments in the fission mass region in the interaction of 0.65, 1.74, 5.1, 8.8 and 12.7 GeV 4 He with 232 Th have been analyzed using the polycarbonate track detector Makrofol in the form of a sandwich. The decay channels ending with one, two, or more (three, four) fragments were detected. We have analyzed the events in which at least one heavy fragment (Z>20) was registered. Fragments produced in the experiment were identified and an event-by-event model-free analysis was performed in order to separate different production mechanisms. We have identified the events produced in fission, deep spallation and fragmentation processes. The cross-sections and experimental features have been determined for the various reaction mechanisms, and their variation as a function of the incident energy has been investigated.

The excitation function of the reaction 232 Th(n, 5nγ)228 Th from 29 to 42 MeV has been measured for the first time at the quasi-monoenergetic neutron beam of the UCL cyclotron CYCLONE employing the 7Li(p,n) source reaction. Taking advantage of the good energy resolution of the planar High-Purity Germanium (HPGe) detectors, prompt γ-ray spectroscopy was used to detect the γ-rays resulting from the decay of excited states of nuclei created by the (n,xn) reactions. The neutron beam was characterized by a combination of time of flight measurements carried out using a liquid scintillation detector and a 238U fission ionization chamber. Fluence measurements were performed using a proton recoil telescope. The results are compared with TALYS-1.4 code calculations.

Synopsis Objective This study investigates the application of D-optimal mixture experimental design in optimization of O/W cosmetic emulsions. Cetearyl glucoside was used as a natural, biodegradable non-ionic emulsifier in the relatively low concentration (1%), and the mixture of co-emulsifiers (stearic acid, cetyl alcohol, stearyl alcohol and glyceryl stearate) was used to stabilize the formulations. Methods To determine the optimal composition of co-emulsifiers mixture, D-optimal mixture experimental design was used. Prepared emulsions were characterized with rheological measurements, centrifugation test, specific conductivity and pH value measurements. Results All prepared samples appeared as white and homogenous creams, except for one homogenous and viscous lotion co-stabilized by stearic acid alone. Centrifugation testing revealed some phase separation only in the case of sample co-stabilized using glyceryl stearate alone. The obtained pH values indicated that all samples expressed mild acid value acceptable for cosmetic preparations. Specific conductivity values are attributed to the multiple phases O/W emulsions with high percentages of fixed water. Results of the rheological measurements have shown that the investigated samples exhibited non-Newtonian thixotropic behaviour. To determine the influence of each of the co-emulsifiers on emulsions properties, the obtained results were evaluated by the means of statistical analysis (ANOVA test). On the basis of comparison of statistical parameters for each of the studied responses, mixture reduced quadratic model was selected over the linear model implying that interactions between co-emulsifiers play the significant role in overall influence of co-emulsifiers on emulsions properties. Conclusion Glyceryl stearate was found to be the dominant co-emulsifier affecting emulsions properties. Interactions between the glyceryl stearate and other co-emulsifiers were also found to significantly influence emulsions properties. These findings are especially important as they can be used for development of the product that meets users' requirements, as represented in the study. Resume Objectif La presente etude examine l' application de la conception D- optimal dans l'optimisation des emulsions cosmetiques H / E. Le cetearylglucoside a ete utilise comme emulsifiant non – ionique naturel, biodegradable, dans une concentration relativement faible (1%), et le melange de co-emulsionnants (l'acide stearique, l'alcool cetylique, l'alcool stearique et le stearate de glyceryle) a ete utilise pour stabiliser des formulations. Methodes Afin de determiner la composition optimale du melange de co-emulsifiants, le design experimental de melange “D- optimal” a ete utilise. Les emulsions preparees ont ete caracterisees par des mesures rheologiques, le test de centrifugation, la conductivite specifique et des mesures de la valeur du pH. Resultats Tous les echantillons prepares sont apparus comme des cremes blanches et homogenes, sauf pour une lotion homogene et visqueuse co- stabilise par de l'acide stearique seul. Les tests de centrifugation ont revele une certaine separation de phase seulement dans le cas de l'echantillon co-stabilise a l'aide de stearate de glyceryl seul. Les valeurs de pH obtenus indiquent que tous les echantillons ont exprime des valeurs legerement acides acceptables pour des preparations cosmetiques. Des valeurs de conductivite specifique sont attribuees a des emulsions H / E a phases multiples avec des pourcentages eleves d'eau fixee. Les resultats des mesures rheologiques ont montre que les echantillons etudies ont affiche un comportement thixotrope non – newtonien. Afin de determiner l'influence de chacun des co-emulsifiants sur les proprietes des emulsions, les resultats obtenus ont ete evalues par le biais de l'analyse statistique (test ANOVA). Sur la base de la comparaison des parametres statistiques pour chaque melange, un modele quadratique a ete selectionne preferentiellement sur le modele lineaire ce qui implique que les interactions entre les co-emulsifiants jouent un role important dans l'influence globale des proprietes des co-emulsifiants d'emulsions. Conclusion le stearate de glycerol s'est revele etre le co- emulsifiant dominant affectant les proprietes des emulsions. Les interactions entre le stearate de glycerol et d'autres co-emulsifiants ont egalement ete trouvese a influencer de maniere significative les proprietes des emulsions. Ces resultats sont particulierement importants car ils peuvent etre utilises pour le developpement des produits qui repondent aux besoins des utilisateurs, tels que representes dans l'etude.

The fission processes from the interactions of 0.65, 1.74, 5.1, 8.8 and 12.7 GeV 4 He with Pb have been analyzed using the polycarbonate track detector Makrofol in the form of a sandwich. The decay channels ending with one, two, or more (three, four) fragments were detected. We analyzed events in which only two heavy fragments ( Z >20) are detected, irrespective of the existence of coincident intermediate mass fragments (8⩽ Z ⩽20). Using the correlation between the common observables which characterize fission events, we identified events originated from thermal (soft) fission and more violent processes. Cross sections, angular distributions and excitation energy have been determined for two fission mechanisms, and their variation as a function of the incident energy has been investigated.

The neutron multidetector DeMoN has been used to investigate the symmetric splitting dynamics in the reactions 58,64 Ni + 208 Pb with excitation energies ranging from 65 to 186 MeV for the composite system. An analysis based on the new backtracing technique has been applied on the neutron data to determine the two-dimensional correlations between the parent composite system initial thermal energy (ECNth) and the total neutron multiplicity (νtot), and between pre- and post-scission neutron multiplicities (νpre and νpost, respectively). The νpre distribution shape indicates the possible coexistence of fast-fission and fusion-fission for the system 58 Ni + 208 Pb (Ebeam = 8.86 A MeV). The analysis of the neutron multiplicities in the framework of the combined dynamical statistical model (CDSM) gives a reduced friction coefficient β = 23 ± 1225 × 1021 s−1, above the one-body dissipation limit. The corresponding fission time is τf = 40 ± 2046 × 10−21s.

We report the study of the reaction 15 MeV/nucleon 238 U + 197 Au , in which up to 7 final heavy fragments have been detected, using a CR-39 plastic nuclear track detector. The measured multiplicity distributions indicate that the binary fission of one (U-like) or both (U-like and Au-like) primary products clearly dominates for peripheral and intermediate impact parameters exhausting more than 80% of the total cross section. Multifragment emission sets in for the most central collisions. Reactions with 3 heavy final fragments, accounting for half of the total cross section, have been analysed event-by-event after measuring the geometrical parameters of each detected track, assuming momentum conservation and using empirical range-energy-charged curves. Most of these ternary processes originate in a two-step mechanism: a initial peripheral projectile-target interaction plus a deep-inelastic process followed by the subsequent fission-like decay of one of the fragments (mainly the quasiprojectile). Indeed, the relative velocity between the two fastest fragments are clearly peaked at values close to the Viola systematics for the fission of a very-heavy nucleus.

The $^{238}\mathrm{U}$+$^{197}\mathrm{Au}$ reaction has been studied at 15 MeV/nucleon bombarding energy. Correlations between two to seven final fragments with $Zg~8$ have been measured using CR-39 nuclear track detectors. An event-by-event kinematic analysis was carried out for three-body exit channel reactions which exhaust about half of the final fragment production cross section. Most of these ternary processes can be associated with intermediate and peripheral impact parameters. The dominant reaction mechanism is shown to be that of a first binary quasielastic or dissipative collision followed by the sequential binary fission of the excited quasi-$U$ (or to a lesser extent of the excited target remnant). We observe also a net drift of nucleons from the target to the projectile prior to its decay.

The timescale for emission of three fragments (Z GT = 8) in the 12.7 GeV He-4+U-238 reaction has been studied using a sandwich configuration of the Makrofol polycarbonate track detector. In events with varying multiplicity of heavy fragments (Z GT 20), the differences of the correlation functions for relative angle and relative velocity between pairs of fragments have been studied in order to determine the fragment emission timescale. A sequential decay mechanism for the excited residual nuclei was found to be consistent with experimental data. It was determined that the fragment emission time decreased with decreasing multiplicity of heavy fragments from 1200 +/- 80 fm c(-1) for events with two heavy fragments to 400 +/- 50 fm c(-1) for events with one heavy fragment.

Reactions of 15 MeV/n 238 U on Ag have been studied by means of CR 39 detector. Analysis of 3 pronged events was done and classified as a function of impact parameter. For 4 and 5 pronged events, two and three steps mechanisms were found.

The Monte Carlo method is employed to calculate the geometrical efficiency of a multi-detector system for fragments produced in heavy ion reactions. This efficiency is defined as a quotient of the number of fragments intercepted by the system and the total number of fragments emitted by the fissioning nucleus in all directions. The multi-detector system consists of six parallel-plate avalanche counters in a hexagonal configuration around the target. Its geometrical efficiency was calculated with respect to the Ar-36 + U-238 reaction at a 7 MeV/u projectile energy.

Neutron and proton yields. spatial and energy distributions were determined on an electronuclear set-up irradiated with relativistic deuteron beams. The experimental results, acquired using both passive and active methods, are compared with the data obtained using MC simulation. The U-blanket performance in terms of fission production rate as well as plutonium accumulation is discussed. An evaluation between the data obtained using relativistic deuteron and proton beams is presented regarding to study the set-up efficiency to incinerate and/or transmute the actinides and fission products. (C) 2009 Elsevier Ltd. All rights reserved.

Reactions of 15 MeV/n 238 U on Au have been studied by means of CR 39 solid state nuclear track detectors. Among the different events observed, all 3-pronged events were selected and examined. It is found that at final state the quasi totality of these events, say 87%, proceed by fission reactions. Analysis in the context of participant-spectator model has shown evidence for two different fission processes. Fission events derived from the break-up of the participant nuclei represent ∼78% of the events, whereas ∼9% issue from the spectator. The mean kinetic energy loss is ∼11 % of the incident energy.

A spallation neutron source consisted of a cylindrical Pb target and surrounded by uranium blanket was irradiated by deuteron beam 1.25 GeV/amu provided from the Nuclotron accelerator at High Energy Laboratory, JINR, Dubna. For radiation protection purpose a polyethylene shielding was placed around the spallation neutron source. Neutron distributions along the surface of the U-blanket were measured by using solid state nuclear track detectors (SSNTDs) as particle and fission detectors. The neutron distributions appear to be similar to those obtained by proton irradiations. Applying a fitting procedure to the experimental data the inelastic cross section of deuteron in Pb was estimated. The escaping neutron distribution from the polyethylene shielding and parallel to the target was also measured and presented to be two orders of magnitude less than that over the U-blanket surface. (C) 2008 Elsevier Ltd. All rights reserved. 23rd International Conference on Nuclear Tracks in Solids, Sep 11-15, 2006, Shanxi Normal Univ, Inst Modern Phys, Beijing, Peoples R China

CR 39 solid state nuclear track detectors have been used to study the reaction products of 17.7, 27, and 35 MeV/nucleon $^{84}\mathrm{Kr}$ on Au and Ag. The visual detectors allow studying interactions producing two or more correlated intermediate mass fragments in the final state. The characteristics of these events are such that they probably arise from a fragmentation process of the quasitarget or some intermediate zone. The cross sections of 3, 4, and (5+6) correlated fragments increase with increasing $^{84}\mathrm{Kr}$ incident energy for both targets.

The excitation function of the reaction 232 Th(n, 5nγ) 228 Th from 29 to 42 MeV has been measured for the first time at the quasi-monoenergetic neutron beam of the UCL cyclotron CYCLONE employing the 7 Li(p,n) source reaction. Taking advantage of the good energy resolution of the planar High Purity Germanium (HPGe) detectors, prompt γ-ray spectroscopy was used to detect the γ rays resulting from the decay of excited states of nuclei created by the (n,xn) reactions. The neutron beam was characterized by a combination of time of flight measurements carried out using a liquid scintillation detector and a 238 U fission ionization chamber and fluence measurements carried out using a proton recoil telescope. The preliminary results are compared with calculations performed using the TALYS-0.72 code.

In the paper different fourth order filter designs with different transfer function approximations are discussed. Specifications on the filters are given for VDSL signal processing. Transfer functions and filter elements are given and sensitivity and noise for each design are calculated. The lowest sensitivity is obtained using a cascade of Rauch biquads, the lowest noise gives Akerberg-Mosberg design and the best selectivity is obtained using an elliptic filter. That leads to compromise in VDSL filter design. Also, transfer function approximation significantly determine overall specifications

207Pb(n,2nγ)206Pb cross section were measured for incident neutron energies between 6 and 20 MeV with the white neutron beam produced at GELINA. The γ‐ray production cross section for the main transition (803 keV, 2+→ 0+) in 206Pb is compared to results obtained at Los Alamos and to the TALYS and EMPIRE‐II code predictions.

In this paper, different the third order filters designs with different transfer function approximations are discussed. The filters should fulfill the specifications for the VDSL signal processing. The standard transfer function approximations are chosen: the Butterworth, the Chebyshev, the Symmetric impulse response and the Elliptic. The filters are designed using the fully differential sections with the small number of elements to obtain the low noise and the high dynamic range, and the low sensitivity. The transfer functions and the filter elements are given and the sensitivity and the noise for each design are calculated. The best results are obtained for the third order filter where the second order block follow the first order block.

The nuclear reactions 207Pb(n,2n)206Pb and 232Th(n,5n)228Th were studied by measuring prompt gamma‐ray emission spectra from the interaction of neutrons with an enriched 207Pb sample and a natTh sample. For 207Pb the measurements were performed at the white neutron beam of the GELINA neutron source at IRMM Geel in the neutron energy range up to 20 MeV. The Th measurements were done at the quasi‐monoenergetic 7Li(p,n)7Be neutron source at the Universite Catholique de Louvain for five peak neutron energies in the range 29 MeV to 42 MeV. The measurements were complemented by model calculations using the code system EMPIRE‐II.

The neutron spectra associated to the two fission modes of Th-226 have been measured in coincidence with the fragment yields of the O-18 + Pb-208 reaction at E-lab = 78 MeV. The pre- and post-fission multiplicities and temperatures have been extracted. Surprisingly, the prefission neutron multiplicities associated with the asymmetric mode are larger than those associated with the symmetric mode.

The processes of production of fragments Z greater than or equal to 8 in the interactions of 12.7 GeV He-4 with U, Pb, Au and Ag have been analyzed using the polycarbonate track detector Makrofol. A sandwich technique was used which enables direct evidence for multiple fragment emission by a single nucleus. The decay channels ending with one, two or more (three, four) fragments were detected. A classification scheme based on the multiplicity of heavy fragments M-H (Z GT 20) was used in order to identify events belonging to the different reaction channels. Cross sections, excitation energies and multiplicities of intermediate mass fragments (8 less than or equal to Z less than or equal to 20) have been evaluated for various reaction mechanisms. The experimental features of the fragmentation process have been analyzed as a function of the target mass. 18th International Conference on Nuclear Tracks in Solids, Sep 01-05, 1996, Cairo, Egypt

Total reaction cross sections of C-12, O-16 and Mg-24 projectiles were determined in several targets, by means of Nuclear Track Detectors. The beams at 4.5 GeV/N for C-12 and Mg-24 and 3.65 GeV/N for O-16 were taken from Dubna accelerator. Our results exhibit the geometrical dependence on nuclear radii. They are in good agreement with Vary's cross sections (Vary, 1975) taking the overlap parameter to be dependent on interacting masses.

Makrofol and cellulose nitrate detectors were used to study the reactions of 2.38 and 3.97 GeV 238 U on heavy targets like 238 U, 208 Pb and 197 Au. Binary, ternary and quaternary fission of the incident ions in reactions with the 12 C of the detectors were also abserved. Branching ratios of multipronged events induced by the heavy targets were determined, as were mass and folding angle distributions for the fission events induced by 12 C.

CR 39 was used as Solid State Nuclear Track Detector (SSNTD) to study the reactions of 17.7 and 35 MeV/n Kr on Ag targets. Cross-sections of each kind of multi-pronged event were calculated and the charge and velocity distributions of the heavy fragments were determined by the calibration of each track from an event by event analysis.

Several parameters influencing tree formation in electrochemical etching of α-particle tracks in CN-85 cellulose nitrate have been studied. A dependence of track diameter on incident α-particle energy and fluence is found.

An SSNTD study of reactions induced by 10 MeV/n U ions on U, Au and Pb targets led to the observation of a new type of fission event which can be explained as a delayed fission.

Cu and Pb targets were irradiated by 3.7 GeV/n 12 C ions and 1.8 GeV/n ions respectively at the Dubna (USSR) and Berkeley (USA) accelerators. CR 39 track detectors were placed up- and downstream of 2.0 cm Cu and 0.8 cm Pb foils. Important attenuation of the number of beam particles passing through the targets was observed allowing for direct total reaction cross section measurements. Good agreement with theoretically calculated cross section was found.

The cross sections for the binary and ternary fission of U, Th, Bi, Pb, and Au induced by 300 GeV protons have been measured with Makrofol polycarbonate detectors. We deduce that the ternary events and most of the binary events with a projected angle ..cap alpha../sub 12/

For a convenient utilization of the track detectors, two techniques are investigated: standard optical system and spark counting. Results for the counting characteristics as a function of the irradiation parameters are given for the makrofol E and cellulose nitrate LR115 type II detectors for the experimental conditions used. The efficiency of detection is given.

The 12C contained in a makrofol detector was bombarded by 2.38 GeV 238U projectiles. The characteristics of the binary fission were studied. It is shown that the cross section is ≃ 1 b, that the mass distribution is only slightly asymmetric and that the most probable fissioning recoil nucleus is (Z,M) = (96,240).

A study of ECE conditions for α-particles and protons registered in CR-39 were attempted. For alphas, a dependence of the mean diameter on energy was obtained. In the case of protons, only slight influence of energy on mean diameter was observed. For the conditions used, the efficiency of the ECE development is given.

By means of makrofol detector we have studied the reaction U + U at 9.02 MeV/AMU and 7.5 MeV/AMU and U + Pb at 7.5 MeV/AMU. We analyse 3, 4 and 5 pronged events and give the cross sections and some geometrical and cinematical properties.

Thin targets of heavy elements are sandwiched between sheets of polycarbonate detectors. These makrofolstacks were irradiated with 300 GeV protons at FNAL and permitted the registration in 4π geometry of all the fission fragments in correlation. The incoming proton beam intensity were made by measuring 24 Na produced in Al foil with a calibrated proportional counter and so we have obtained the binary and ternary fission cross section of U, Th and Bi. A new kind of event, the break up of the nucleus in 4 fragments was found and studied.

The emission of fragments ( A ≥16) from reaction of 4 He with 197 Au has been studied at bombarding energy of 12.7 GeV. Policarbonate Makrofol in sandwich form was used as a detector. Fragments produced in the experiment were identified and an event by event model-free analysis was performed. The decay channels ending with one, two or more (three, four) fragments were detected. A classification scheme based on the multiplicity ( M H ) of heavy fragments ( A ≥40) was used in order to define multifragmentation ( M H = 0), spallation ( M H = 1) and fission ( M H = 2) events. The various experimental features of the fragmentation process are discussed.