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The purpose of this paper is to determine the feasibility of identifying the creep rupture of reactor cladding tubes using acoustic emission technique (AET).

The creep rupture tests were carried out by pressuring stainless steel capsules upto 6 MPa at room temperature and then heating continuously in a furnace upto rupture. The acoustic emission (AE) signals generated during the creep rupture tests were recorded using a 150 kHz resonant sensor and analysed using AE Win software.

When rupture occurs in the pressurized capsule tube representing the cladding tube, AE sensor attached to a waveguide captures the mechanical disturbance from the capsule and these data can be advantageously used to identify the creep rupture event of the cladding tube.

The creep rupture data of fuel clad tube is very important in design and for smooth operation of nuclear reactors without fuel pin failure in reactors.

AE is an advanced non-destructive evaluation technique. This technique has been successfully applied for on-line monitoring of creep rupture of the reactor cladding tube which otherwise could be detected by thermocouple readings only.

Quasi shear and tensile mode stress‐rupture and quasi shear mode creep behaviours were investigated for aged production surface mount soldered connections of 127 mm pitch, rigid gullwing and J‐bend configurations at ambient and 60°C (on limited specimens) environments. These joints were manufactured by the vapour phase reflow soldering process using a 63Sn‐37Pb solder composition. Metallographic examinations and fractrographic studies were also performed on appropriate specimens to characterise the metallurgical attributes of the solder and the joint failure. A relatively coarse solder microstructure was observed with both joint configurations. The steady‐state creep data of both soldered joints exhibited two distinct creep regimes. A grain boundary‐controlled regime at low loads with a slope of 042 for gullwing and 0?50 for J‐bend joints was followed by a dislocation climb‐controlled regime at high loads with a slope of 0?13 and 0?24 for gullwing and J‐bend configurations, respectively. The log‐log plot of applied load varied linearly with rupture time for the entire load range for the respective soldered joints for both modes of testing at room temperature. A transgranular fracture morphology was found to predominate for the entire load regime for the quasi shear mode tested gullwing joints. A mixed‐mode fracture morphology with predominantly transgranular features was observed for both low and high loading conditions for quasi shear mode tested J‐bend specimens. The steady‐state creep elongation in shear showed a strong dependence on the applied load for both types of soldered joints. This was primarily attributed to the presence of relatively large creep transients, especially at higher loads.

With the continued miniaturisation of electronics equipment, a more detailed examination of the mechanical behaviour of solders is required to ensure reliability in performance. The paper reviews various aspects of the interpretation of the creep response of lead‐containing and lead‐free alloys. It demonstrates the necessity of acquiring stress‐rupture data over as long a period as possible to avoid non‐conservative extrapolation. For example, at 75°C, the transition in slope of the applied stress vs time to rupture plot occurs after about 1,000 h for Sn‐37Pb, although for the lead‐free alloys examined no such transition is observed within this timescale. Sometimes, deformation may be a more appropriate failure criterion than rupture, and it is shown that for Sn‐37Pb this may result in substantially shorter failure times than utilising a rupture criterion. The quality of life estimation methods then depends upon the extent of this stage when the creep rate is a minimum. The Y factor (t_m : t_r) where t_m is the time spent in steady state or within 10 per cent of the minimum creep rate, for all the solders examined at 75°C generally falls into the 20‐30 per cent range. Estimations of creep life may substantially under predict because of this.

Simple discrete element models using PFC^2D models with bonded assemblies of particles were used to numerically simulate direct tension and block punching tests on thin spray‐on tunnel liner materials to gain insight about the liner support mechanisms. PFC^2D input parameters were calibrated such that the rupture load and elongation at rupture were similar to the laboratory test data. The calibrated model of the liner material was then used to simulate a liner around a highly stressed tunnel in rock where stresses caused extensive fracturing near the top of the tunnel. The effect of the liner was analysed by modelling the tunnel with and without the liner and showed that the liner had minimal impact on fracture propagation in the rock because of the liner's highly deformable nature. However, the liner was able to retain the fractured rock in place.

The objective of the study is to examine the response of reinforced concrete (RC) structures subjected to Near-Fault Ground Motions (NFGM) and highlight the importance of considering various factors including the influence of the relative geographical position of near-fault sites that can affect the structural response during an earthquake.

In this paper, the response of a four-storey RC building subjected to NFGMs with varied characteristics like hanging wall and footwall in conjunction with directivity and the effect of pulse-like ground motions with rupture direction are investigated to understand the combined influence of these factors on the behavior of the structure. Furthermore, the capacity and demand of the structural element are investigated for computing the performance ratio.

Results from this study indicate that the most unfavorable combinations for structural damage due to near-fault ground motion are the hanging wall with forward rupture, the fault normal component of ground motions, and pulse-like ground motions with forward directivity.

The results from this study provide valuable insight into the response of RC structures subjected to NFGM and highlight the importance of considering various factors that can affect the structural response during an earthquake. Moreover, the computation of capacity and demand of the critical beam indicates exceedance of desired limits, resulting in the early deterioration of the structural elements. Finally, the analytical analysis from the present study confirms that the hanging wall with forward ruptures, pulse-like motions, and fling steps are the most unfavorable combinations for seismic structural damage.

The purpose of this paper is to evaluate advanced mathematical electrochemical noise analysis (ENA) as a way of corrosion monitoring for carbon steel.

The electrochemical potential/current noise was recorded simultaneously with a working‐reference‐working electrode set up and the processing of data was performed through fast Fourier transformation (FFT) and wavelet transformation (WT) routes. The formation and rupture of carbonate films on St37 steel electrodes in a 0.5 M sodium bicarbonate electrolyte was studied for 20 h utilizing an electrochemical noise approach.

Although the slope of mid‐range of noise impedance exhibited a mechanistic style, and increased with film formation and decreased with film rupture, FFT of potential noise was more sensitive to film formation and rupture. WT of potential noise depicted that ν=1.41 × 10⁻² Hz was the boundary frequency in the film formation. At frequencies higher than the mentioned limit, the fraction of distributed potential decreased with time. However, the opposite behavior was observed during the rupture of the film.

The preliminary results show that the proposed novel electrochemical method, wavelet and FFT ENA, is very able to monitor the corrosion behavior of carbon steel corrosion in carbonate media.

The purpose of this paper is to apply grey statistical model to identify and classify live fault rupture.

Based on grey statistical mode, this paper uses eight faults' ripping speed observation data from 1997 to 2001, according to the grey statistics method for analysis, and recognizes active fault rupture situation. Using the conventional methods, namely taking all faults monitoring stations' average dislocation rate to analysis and make judgment, the average results are obtained.

The results show that the results are closer to reality because the grey statistical evaluation method has considered dislocation rate and other discrete factors.

The method exposed in the paper can be used to monitor and recognize live fault rupture in earthquake prediction.

According to the fault dislocation rate, this paper advances active fault rupture identification and classification method based on grey statistical model.

Multilayer printed wiring boards make use of electrodeposited copper from two sources. Copper for conductor traces comes from foil manufacturers through thin laminate suppliers. Copper plating for layer interconnection is performed in an in‐house PTH process. Each source makes use of plating chemicals that are obtained from industry suppliers, but production requirements inherent in foil manufacture or in PTH processing can cause variations that occasionally result in copper deposits that exhibit poor hot strength. In a PWMLB, this can result in corner cracks, barrel cracks and inner layer cracks because some of the copper deposits will be susceptible to fissuring under thermal stress conditions. The phenomenon of hot fissuring is caused by the presence of co‐deposited impurities that degrade the hot strength of the deposit due to easy grain boundary separation at elevated temperatures. Stresses imposed by a solder float test, by soldering or by thermal cycling are then sufficient to cause microcracking in a copper plate that is in this condition. In this paper, the author describes how changes in the quality of copper plate can be monitored with a hot rupture mechanical test method. By testing plated copper samples before board fabrication, it is possible to detect and evaluate harmful effects such as fissuring before the electroplated copper is used in a PWMLB assembly.

The purpose of this paper is to propose a processual framework of psychological contract breach, which maps holistically the interactions among concepts drawn from the trust and justice literature. However, the price of a holistic picture is frequently a lack of depth of analysis of any single variable, and consequently the second part of the paper seeks to unpack a central variable, circumstances of breach.

Draws on findings from a four‐year qualitative study and investigates the psychological contract in situ. The issue of circumstances of breach was explored inductively by applying in‐depth employee case histories using theory‐based sampling.

Key findings indicate that breach may occur as a result of direct or indirect organisational actions. Further the degree of reaction may differ according to the type of trigger (i.e. a distributive, procedural or interactional justice issue) and also the extent to which the organisation is held responsible.

Based on an in‐depth study of one organisation over time; further research is required to ascertain the generalisability of the key findings.

The implications for the practice of management surround the issue of unanticipated results of actions. Changes to substantive, distributive justice issues are likely to result in psychological contract violation or rupture unless handled with care. The repercussions of relationship fracture include diminished employees attitude and, perhaps more importantly for the organisation, negative behaviour.

The key contribution of the paper is that it presents a new model of psychological contract and elucidates a key aspect of the holistic model using empirical data.

This paper aims to examine the bioactive compounds and texture properties of cereal bars formulated with banana peel flour during storage.

Seven cereal bars were produced and stored during 11 months, under vacuum and protected from the light. The total phenolic compounds, the activity antioxidant by ABTS [2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] method, the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) method expressed as EC50 (concentration required to reduce the original amount of free radicals by 50 per cent) and texture properties were evaluated over the storage period.

In general, total phenolic compounds decreased during storage (from 4.19 to 1.11 mg GAE. g-1f.w.). Although the total antioxidant activity (ABTS method) increased during the fifth month, it reduced during storage (from 3.41 to 0.30 µmol TE.g-1f.w.); and the EC50 was not modified in many formulations, though it decreased in other formulations during storage period (from 3913 to 19221 g fruit.g-1 DPPH). The force of rupture began to increase in the fourth month (reaching 62.4 N), and hardness began to increase in the ninth month (reaching 444 N). The formulation and time factors influenced the total phenolic compounds, total antioxidant activity (ABTS method), force of rupture and hardness, while EC50 was only influenced by the formulation (p-value = 0.001). A principal component analysis showed that time had little effect on the most important characteristics considered in description of the cereal bars.

Cereal bars can be consumed up to the third month of storage, considering the texture of the products. Moreover, the presence of bioactive compounds in cereal bars depends on the addition of banana peel flour, which it contributes to the insertion of total phenolic compounds and total antioxidant activity in cereal bars, aggregating functional properties in these products.