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This paper describes a new principle of charged-particle identification by plastic track detectors. We find that the rate of chemical etching (by a suitable reagent) along the track of a heavy ion in a plastic depends only on the primary ionization rate, which, as the particle slows down, increases at a rate that depends uniquely on atomic number Z and mass A. To identify the Z, A, and energy of a particle we can either measure the etching rate at a known residual range [by analogy with a (dE/dx) -E detector] or measure the etching rate at two known points along the trajectory in a stack of plastics. We present experimental data for B 10 , B 11 , C 12 , N 14 , and O 16 ions from the Yale accelerator, showing that masses differing by 9% can be resolved. Unique features of this method are its discrimination against intense background radiation and its combination of high resolution with large collecting area, which make it feasible to do certain cosmicray experiments, such as the detection of Be 10 nuclei. D IELECTRIC detectors, 1 in which nuclear particle tracks are made visible by a preferential chemical etch, are uniquely useful for certain studies in nuclear physics, geophysics, and astrophysics. One of their most valuable features is the existence of a critical primary ionization rate such that only particles with primary ionization rates above the critical rate will produce etchable tracks. 2 This property has been exploited as a means of setting lower limits on the masses of those particles that record tracks. Inorganic crystals have been used, for example, to measure formation cross sections and angular distributions of ternary fission fragments without any background from an impinging beam of argon ions, 3 and to measure the abundance of cosmic rays with Z>30, relative to the abundance of iron nuclei. 4,5 In this paper we show how dielectric detectors can be used to identify atomic numbers and to distinguish between isotopes of certain energetic nuclei. Although the data reported here apply only to one brand of cellulose nitrate, the principle is valid for other plastics and possibly for other dielectric solids. This discovery extends the usefulness of dielectric detectors and makes feasible the identification of certain energetic isotopes in solar and cosmic rays and of light nuclei emitted in asymmetric fission. The principle of charge resolution is based on our observation, to be described below, that the rate of chemical etching along a particle track in a plastic depends only on the primary ionization, which is a function of the velocity and the atomic number Z of the particle.

, A. M. (2018). An investigation of the viscoelastic creep behaviour of basalt fibre reinforced timber elements. Construction and Building Materials, construction and building materials(187), 220-230.

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The objective of this study was to characterise the behaviour of cross laminated timber (CLT) panels and the influence of the panel lay-up on the failure strength. Three different panel configurations of thickness, 60 mm, 100 mm, and 120 mm, were loaded in the out-of-plane direction. The 60 mm and 120 mm panel configuration comprised three layers of equal thickness, and the intermediate 100 mm thick panel comprised five layers of equal thickness. The mean and characteristic bending and rolling shear strength of the panels were examined. The results show that the mean bending and rolling shear strength decrease with the panel thickness. The characteristic results have shown that there is an influence because of the number of boards within the panel. The characteristic bending strength values for the five-layer 100 mm thick panel were found to be higher than that of the three-layer 60 mm panel. The characteristic rolling shear values decreased in the five-layer panels, however, the increased number of layers subjected to the rolling shear results in a reduced variability in the rolling shear strength.2 of 15 used for the manufacture of CLT are generally conditioned to a moisture content (u) of 12 ± 2% and are visually or mechanically strength graded. The common strength classes according to EN 338 [2] are C24 for a homogeneous layup, C24 for longitudinal layers, and C16/C18 for the transverse layers in a combined layup. In general, the guidelines and requirements of the adhesive manufacturers must be followed in the manufacture of CLT panels. It must be stated that some parameters, such as the bonding pressure, the quantity of applied adhesive, and the moisture content of adherends, are based on experience with glulam production [3][4][5][6][7].Many studies have examined CLT and its uses in the timber construction industry. Its excellent in-plane and out-of-plane strength, rigidity, and stability have allowed larger and taller buildings to be built [3,[8][9][10][11][12]. In Europe, spruce is largely used when manufacturing CLT, however, many other timber species have been investigated worldwide. Fortune and Quenneville [11] aimed to establish the use of CLT in New Zealand using locally-grown Radiata pine, bonded using resorcinol adhesive. In Japan, Sugi timber CLT panels were manufactured by Okabe et al. [13]. In the United States, Hindman and Bouldin [14] produced CLT using Southern pine, which was tested to establish the bending strength, bending stiffness, and shear strength. The CLT panels made from Scottish Sitka spruce was investigated by Crawford et al. [15]. Four CLT panels for each panel configuration (three-and five-layers) were prefabricated using Sitka spruce boards, graded to C16, and bonded with polyurethane (PUR) adhesive. Established bending strengths and stiffnesses in-and out-of-plane were not dissimilar to commercially available CLT panels, manufactured in Central Europe. Similarly, a sample of the CLT panels were manufactured from Irish Sitka spruce by Sikora et al. [9]. Sikora et al. [9] test...