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The factors that influence the symmetry of an imploding detonation are investigated experimentally and theoretically. Detonations in sub-atmospheric acetylene–oxygen were initiated and made to converge in an apparatus that followed that of Lee and Lee (Phys Fluids 8:2148–2152, 1965). The width of the test section was controlled with a wave-shaping insert, which formed the test section against the viewing window, creating an effectively two-dimensional problem with a channel width comparable to the detonation cell size. The convergence of the detonation was observed via self-luminous open-shutter photography and high-speed videography. The resulting videos were analyzed to quantify the wave speed, degree of asymmetry, and direction and magnitude of the offset in the center of convergence. To determine the experimental parameters that influence the symmetry of the imploding wave, the wave-shaping insert was intentionally canted by 0. 3 ∘ -- 0. 6 ∘ , accentuating the asymmetry of the imploding detonation. The experiment was modeled using a Huygens construction wherein the detonation is treated as a collection of wavelets, each assumed to propagate locally at a velocity determined by the channel width. The results of the model reproduced the observed offsets in detonation convergence from the center of the apparatus, confirming that velocity deficits resulting from the narrow channel width control the observed asymmetry. [ABSTRACT FROM AUTHOR]

Currently, there are practically no people left who have seen the consequences of the use of nuclear weapons. This is the reason for certain frivolous statements about the advisability of using tactical nuclear weapons to solve certain tactical problems. The purpose of this work is to remind, using the example of the consequences of the atomic bombings of the cities of Hiroshima and Nagasaki, how does the nuclear war looks like in reality. Materials and Methods. Open sources from the Cold War era and more recent reviews of the consequences of the use of nuclear weapons were analyzed. The analysis was carried out from general to specific, i.e. from the understanding of physical processes underlying a nuclear explosion and determining the design of the nuclear devices, to the specific consequences of their use. Discussion. The article analyses the history of the creation of the «Gadget», «Fat Man» and «Kid» bombs, their design, preparation and the results of the use. Detailed descriptions of nuclear explosions and the consequences of their use, made both by those who used nuclear weapons and by those against whom they were used, are provided. Being imperfect in design and ineffective in using fissile matter, they showed stunning power even for the present time, destroying two densely populated cities and at least 106 thousand people at once. Real examples show the features of the destruction of engineering objects and the impact on people of the damaging factors of a nuclear explosion. Attention is drawn to the fact that the power of the bombs used was 15 and 22 kt, respectively. According to modern NATO classification, these are tactical nuclear weapons. It is designed to destroy targets in the tactical depth of enemy troop deployment (up to 300 km). The maximum power of tactical ammunition according to NATO standards is up to 100 kt. It means that the yield of the tactical ammunition used in battle will depend on the tactical mission, and not be limited to a few kilotons. Conclusions. The use of tactical nuclear weapons without escalating their power, causing large casualties among the population and the risk of being drawn into a global nuclear war is impossible. Currently, the world is oversaturated with nuclear and thermonuclear weapons. Some countries possess them secretly, others have the potential to create such weapons. Therefore, any use of nuclear weapons by anyone will lead to the lowering of the threshold of nuclear deterrence. It will become a common thing during the resolution of military conflicts.

Naval structures owing to their operational conditions get exposed to extreme loadings and environments. Along with blasts generated through explosion events, enclosed naval structures are also vulnerable to structural dynamic instability, leading to implosion and catastrophic failure. This review explores state of the art in research work carried out to understand the deformation and damage mechanism of naval sandwich structures both on the surface and deep-sea environments. A brief overview of the current understanding regarding the response of sandwich structures to air shock, underwater shock, and implosion owing to dynamic instability is provided. The effect of environmental conditions on the dynamic response of these structures is also discussed. The article further discusses various mitigation techniques proposed to improve the blast and implosion mitigation of sandwich structures and points out the current research gaps existing in the common understanding. [ABSTRACT FROM AUTHOR]

Данная работа посвящена описанию форм и способов выражения эмоции гнева в бурятском языке. Здесь рассматриваются глагольные фразеологизмы бурятского языка со значением гнева, которые выражают данную эмоцию в предельных ее проявлениях. Предельность в выражении эмоции, особенно эмоции гнева, ярче всего проявляется именно в устойчивых сочетаниях, к которым относятся фразеологизмы. В разных обстоятельствах гнев выражается вовне или направлена внутрь, скрыта, подавлена. Такие способы нами названы как эксплозивные и имплозивные. Анализ примеров из художественной литературы и разговорной речи показал, что в бурятском языке больше всего эксплозивных фразеологизмов. Данный факт обусловлен природой эмоции.

The interface instability and turbulent mixing of perturbed multi-modes Air/SF6 interface driven by implosion in spherical geometry are numerically investigated. The results show the complex evolving laws and physical mechanisms of turbulent mixing. After the incident imploding shock, the transmitted shock wave moves towards the centre and bounces off outward to produce the second impact, which is a combination of reshock and Taylor wave rather than a single one like in planar case, and forms the loading/unloading effects. The following rebound impacts repeat this assembled loading/unloading process. In the whole process, the turbulent mixing zone (TMZ) growth is closely related to the multiple loading/unloading features. The Richtmyer-Meshkov instability (RMI), Rayleigh-Taylor instability (RTI), Rayleigh-Taylor stabilization (RTS) and Bell-Plesset (BP) effects coexist, and the competition mechanism results in the TMZ width growing in an oscillatory way. The statistics properties of TMZ are highly related to the multiple shocks process. The fluids mixing across TMZ is asymmetrical but behaves in a self-similar way. The evolution of TMZ has a high degree anisotropy, especially around the two edges of TMZ, the turbulent flow is also highly intermittent. When the turbulent mixing develops fully the energy spectra approach k-1 scaling law at the inertial subrange. [ABSTRACT FROM AUTHOR]

A new fuel compression method for a fast ignition scheme is discussed. To form a high areal density fuel plasma for the ignition condition, homogenous isentropic compression (HIC) with solid spherical target is effective. We improve a multi-step pulse shape method that uses progressive shockwaves and reflected shockwaves for the compression, where a precisely controlled step-pulse laser drives the shockwaves to compress the fuel and suppress entropy increase. Another advantage of this approach is the relatively smooth high dense fuel is distributed at maximum compression time, compared to our previous design based on Kidder’s HIC method. In addition, we insert a power dip as a preconditioning before the last pulse step to reduce the electron and ion temperature near critical density. As a result, an optimum implosion is designed using 245 kJ of implosion laser energy to meet the ignition condition.

The processes of ray energy transfer using hyperbolic formations and the accompanying ef)fects are considered. A new concept of the optical system of a solar energy concentrator and varieties within its framework are proposed, aberrations that occur in such systems and the possibility of transmitting ray energy using a hyperboloid system consisting of surfaces of the second and higher order are considered. The possibility of creating the effect of self-focusing in mirror optical systems is considered. [ABSTRACT FROM AUTHOR]

We present an analytic thick shell model for indirect-drive ICF implosions that starts by using the Rocket equation to evaluate peak fuel kinetic energy and hence by energy balance, stagnated fuel internal energy. We then use the approximation of the hot spot decelerating adiabatically to an isobaric stagnated state coupled to a self-consistently calculated fuel aspect ratio. The model, validated by 1D radiation-hydrodynamics simulations, provides sensitivities of indirect-drive yield, DSR and ignition metrics to a host of initial and final state capsule and hohlraum parameters, applicable to the current relevant regime of igniting implosions. The model is used to highlight parameter trade-offs and estimate expected sensitivity in 1D compression, stagnated areal density and yield at current and higher performance levels. Several new insights are presented. Of note, we explain the weak dependence of ablator thickness on implosion velocity for designs with buried dopant layers, the uncertainty in performance improvement when adding fuel or reducing initial hot spot density, and the role of ionization energy and albedo in setting ablator efficiency. [ABSTRACT FROM AUTHOR]

Rational indicators for the development of oil and gas fields are related to the systemic maintenance of a given level of perfection of formation opening in bottomhole zones of producing or injection wells. This need arises with the colmatation of the natural collector by mechanical, asphalt and tar-paraffinic particles, leading to a decrease in productivity, acceptance of wells and the need to restore the inflow by methods of artificial action on the bottomhole formation zone. Analysis of the effectiveness of the application of various methods of stimulating the flow of reservoir products in the fields of the Timan-Pechora oil and gas province (based on field data) allowed to argue the success of using hydraulic fracturing, thermogas chemical, and shock-depressive effects on the bottomhole formation zone. The prospect of the development of technical means for impact-depressive (implosion) impact on the bottomhole formation zone favorably distinguished by simplicity, cheapness, manufacturability and accessibility is shown. The designs of implosion hydrogenerators of single and multiple pressure are analyzed, shortcomings of technical devices are identified and ways of improving mechanisms are outlined. The results of effective application of various downhole generator devices for increasing productivity and well acceptance are presented.

Prolonged exposure therapy (PE) has gained strong empirical support for posttraumatic stress disorder (PTSD) in the general population. However, some authors have suggested that exposure therapies may be less effective for the treatment of PTSD in older adults. There is a paucity of empirical treatment studies for older adults with PTSD. The extant studies are briefly reviewed. There are indications that exposure therapies can be feasible, safe, and efficacious for older adults. However, the degree and maintenance of gains may be reduced in older adults relative to younger adults. A case example is presented to provide a detailed illustration of PE conducted with an older adult. The treatment is presented in five phases, including standard treatment components and suggested modifications for older adults. The modifications include careful use of terminology, slowing down the presentation of some information, involvement of family members, and utilizing technology to minimize the negative effects of physical impairments and stigma. • Prolonged exposure therapy (PE) has strong empirical support for PTSD • Exposure therapies can be feasible, safe, and efficacious for older adults • A detailed case example describes PE conducted with an older adult • The treatment in the example is presented in five phases • Modifications for PE with older adults are suggested [ABSTRACT FROM AUTHOR]

Until now, the intensification of ion exchange processes (sorption, desorption, washing of ion exchanger) remains an urgent problem in obtaining commercial strippants. This paper presents the study of ultrasonic (US) effects on the process of uranium sorption from pregnant solutions by ion-exchange resin at operating in-situ leach recovery (“ISR”) uranium production. The study and evaluation of effectiveness of ultrasonic intensifying the ion exchange processes was implemented at one of the mines of NAC Kazatomprom JSC. Ultrasonic pulses periodically generated by emitters produced effects on the whole working space of the mass transfer apparatus. Thus, the whole mass of reagents is kept in continuous motion, and the whole surface of the anion exchanger grains is permanently purified during the ultrasonic device operation. The study findings showed that the ultrasonic intensification of the sorption process allows: - increasing the sorption rate by 6.4 times at uranium concentration in the pregnant solutions of 0.003 g/m3; - increasing the sorption rate by 1.4 times at uranium concentration in the pregnant solutions of 0.014 g/m3; - achieving weighted average increasing the sorption rate by 1.3 times through applying the ultrasonic treatment; - increasing full dynamic exchange capacity of the ion exchange resin for uranium in 1.13 times at keeping mechanical strength of the ion exchanger grains.

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Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara Ion Ionescu de la Brad Iasi, Seria Horticultura is the property of University of Agricultural Sciences and Veterinary Medicine (Editura Ion Ionescu de la Brad) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrodynamic processes in a vertical well casing during implosion are considered. Mathematical modeling of the motion of a two-phase medium with a free surface is based on the volume of fluid method. Unsteady Reynolds-Averaged Navier-Stokes equations are supplemented by the Menter’s Shear Stress Transport turbulence model. Numerical calculations were performed by the finite volume method using the open integrated platform OpenFOAM. It was found that the depression period is 1 s, and the maximum pressure at the control point is 1.8 times higher than the hydrostatic pressure at the given input parameters.

• Implosion tests are conducted using water only and the combination of water and nitrogen gas. • The ovality and thickness unevenness of the test models are measured. • The effects of pressurising rates on the ultimate strength of the test models are investigated. • Dynamic pressures in terms of short duration pulses are also monitored during the collapse event. • The effect of geometric parameters on the ultimate strengths are numerically conducted. Experimental studies are conducted to investigate the implosion characteristics of thin cylindrical aluminium-alloy tubes. The effects of various parameters that generate different responses on the implosion behaviours are investigated. Aluminium-alloy tubes are fabricated from a 6061-T6 material and designed in the range of 2.5–6.7 length-to-diameter ratios; wall thickness-to-diameter ratios are varied from 55 to 69. The geometric imperfection parameters, defined as the initial ovality and thickness unevenness, are considered. Two different pressurising media, i.e., water only and the combination of water and nitrogen gas are employed. In addition small- and medium-sized of pressure chamber are utilised to clarify the pressure drop after the ultimate strength reached. Furthermore, non-linear finite element analyses, benchmarked for quantitative validation and comparison of the imploded tubes, are conducted. The numerical benchmark quantities are initial ovality, thickness unevenness, and air-backed fluid cavity parameters. The results of these experiments indicated that the effects of combined water and nitrogen can reproduce a constant pressure environment similar as actual undersea conditions, but the combined pressuring media can reduce the pressuring rate. [ABSTRACT FROM AUTHOR]

In what has been called the "Bartleby Industry," Herman Melville's "A Story of Wall Street" has often been disproportionally evaluated by political theorists for its capacity to be read as a story of resistant subjectivity. Specifically singled out by such critics as an anti-systematic symbol, Bartleby is raised up to the condition of the revolutionary agent who prefigures the political subjectivity of post-industrial society. Taking issue with such premediated political readings, this paper attempts to deconstruct symbolic representations of Bartleby which separates Bartleby from Bartleby. Analyzing the textuality of Bartleby as the autobiography of the lawyer, I argue that critical theorists', especially Giorgio Agamben's, lack of attention to the issue of desire of the lawyer leads to the allegorical over-representation of Bartleby for the theoretical justification of political positions. Appropriating a literary figure for the means of political argumentation, these critical theorists disregard the way Bartleby's story is told by the neurotic lawyer. Agamben valorizes Bartleby as the tragic hero of impotentiality, not questioning the reliability of the lawyer-narrator. What lies beneath the lawyer's repeated emphasis on the insanity of Bartleby's "passive resistance" is defense mechanism to cover up his own madness and fear. Without considering how Bartleby's fabula is structured as a part of the lawyer's syuzhet, any configuration of Bartleby results in an allegory of reading. Focusing on the way the lawyer's autobiography pathologizes Bartleby's biography, I argue that Bartleby resists the discursive system of signification which sentimentalizes him and normalizes the lawyer's anxiety into conscientiousness. [ABSTRACT FROM AUTHOR]

The Nigerian political class operates within convenient and exclusive networks that support a core political composition, that itself is predatory, authoritarian and disconnected from society. Since democratization began in 1988, political competition has intensified, but bureaucracies have remained only moderately effective and political parties and civil society have shown continuing weakness while the elite continually holds the polity by the jugular by way of power contestation and domination. While successive political leaders are unable to offer even the most basic services to the people, more than ever before, it appears the mass public only represents a legitimizing tool for electoral indiscretions. However, the present elite fragmentation (as manifested in crises among agencies and cabals in the executive, the antagonistic dispositions among leaderships of the three arms of government and ruling-opposition parties confrontations) in Nigeria, though at face value, may illustrate some implications of Elite Cartel corruption, and portends some dangers for the fragile political system in the country, it may also serve some unintended purposes which this study seeks to unravel. These developments, combined with deep divisions within the country's elite, may have reinforced the fragility of the nation's democracy and governance neglect to the detriment of the poor. If elite power and roles, despite structural differentiation, have long endured by recurring and extending through time and space without producing meaningful social change, can the present internal wrangling signify a weak point to be explored by the disenchanted mass of the people? Can the Nigerian elites become victims of their own creation - poor governance- or the oligarchic implosion is just a passing phase that will fade away with possible future mutual compromise? Adopting the Weberian rational approaches to elite formation and attitudes, this study examines the capacity of the ruling minorities to form cohesive power actors, that is, to act in a solidary, coherent and deliberate manner in contradistinction to the mass resentment among the populace, particularly in the face of elite fragmentation. [ABSTRACT FROM AUTHOR]

The Nigerian political class operates within convenient and exclusive networks that support a core political composition, that itself is predatory, authoritarian and disconnected from society. Since democratization began in 1988, political competition has intensified, but bureaucracies have remained only moderately effective and political parties and civil society have shown continuing weakness while the elite continually holds the polity by the jugular by way of power contestation and domination. While successive political leaders are unable to offer even the most basic services to the people, more than ever before, it appears the mass public only represents a legitimizing tool for electoral indiscretions. However, the present elite fragmentation (as manifested in crises among agencies and cabals in the executive, the antagonistic dispositions among leaderships of the three arms of government and ruling-opposition parties confrontations) in Nigeria, though at face value, may illustrate some implications of Elite Cartel corruption, and portends some dangers for the fragile political system in the country, it may also serve some unintended purposes which this study seeks to unravel. These developments, combined with deep divisions within the country's elite, may have reinforced the fragility of the nation's democracy and governance neglect to the detriment of the poor. If elite power and roles, despite structural differentiation, have long endured by recurring and extending through time and space without producing meaningful social change, can the present internal wrangling signify a weak point to be explored by the disenchanted mass of the people? Can the Nigerian elites become victims of their own creation â€" poor governance- or the oligarchic implosion is just a passing phase that will fade away with possible future mutual compromise? Adopting the Weberian rational approaches to elite formation and attitudes, this study examines the capacity of the ruling minorities to form cohesive power actors, that is, to act in a solidary, coherent and deliberate manner in contradistinction to the mass resentment among the populace, particularly in the face of elite fragmentation. [ABSTRACT FROM AUTHOR]

Experimental data pertaining to weak faults requires construction of microscopic models of the earthquake sources. This study proposes a new high-energy mechanism of transformation of potential energy of strata, saturated with free or bounded fluids, into a kinetic energy of motion of rocks. The proposed approach relies within the framework of classic statistical theory. The high-energy phenomena at a nanometer level are generated by self-consistent molecular fields acting on individual particles. The analysis is carried out using the Bogolyubov-Born-Green-Kirkwood-Yvon equations for the particle group distribution functions. We have investigated the number of high-energy phenomena: (1) the emission of atoms and molecules with high energies from the abruptly opened surface of a condensed system; (2) the implosion of convergent streams of high-energy particles, accompanied by a phenomena of their shock dissociation and ionization, with a subsequent formation of partially ionized plasma; and (3) the recombination processes inside a plasma leading to a formation of molecules with high kinetic energies. The initiation of an earthquake occurs due to an abrupt opening of a cavity in the fluid-saturated medium. At certain thermodynamic conditions, the work function of atoms and molecules from the surface of the system may take negative values. As a result, the emission of molecules of fluids from the cavity walls will generate the high-speed streams of molecules. The emitted flux of molecules leads to the phenomena of implosion, impact dissociation, and ionization of the molecules. This plasma state of the medium is sufficient for an explosion. The explosion initiates a self-supporting chain of consequent explosions in a plane of the tectonic fault. As an example, we have considered the Bridgman explosion of serpentinite. [ABSTRACT FROM AUTHOR]

The text consists of two parts. The first one establishes a general framework for understanding the contemporary crisis. The basic thesis is that it is impossible today to view the problem of the humanities' legitimacy as separate from the order of the positive sciences and the epistemological problems of positive, applied and model-based sciences (such as mathematics). The problem facing the humanities is not so much one of legitimising the status of its own knowledge as the question how it relates to the issue of life forms. The second thesis is that the imagination remains the epistemological category that generates concepts. The second part of the article introduces the concept of "the implosion of time" as a catastrophic image-thought, followed by an analysis of Lars von Trier's film Melancholia (2011). [ABSTRACT FROM AUTHOR]

For accurate electron temperature and density diagnostics in laser high-temperature plasma implosion, opacity of Krypton (Kr) helium- β and Balmer- α lines are discussed, and ratio of escape factor of the two X-rays are calculated, both for Gaussian and Holtzmarkian profiles. Finally, the line ratios of the two X-ray lines are analyzed for optically thin and thick plasmas. Results indicate that for the Gaussian profile, the line ratio varies greatly with the opacity of the Kr helium- β line, which provides excellent source for temperature and electron density diagnostics; while for the Holtzmarkian profile, the line ratio varies less with the opacity of the Kr helium- β line, which can be used for escape factor diagnostics. This method is significant in accurate plasma diagnostics using X-rays under the condition of optically thick. [ABSTRACT FROM AUTHOR]

To deal with the effect of liquid storage on the distribution of implosion, a fluid–solid coupling model is built for the shared nodes of implosion in the liquid storage tank. The displacement compatibility and acceleration and speed coupling are achieved between the implosion field (gas, liquid) and liquid storage tank. First, using this model, the implosion-generated overpressure distribution and structural response under the working condition of half filled tank are obtained. The results show that the overpressure, displacement and stress are high on the shell near the liquid level. Then, the effects of both the TNT equivalent and liquid level on implosion in the liquid storage tank are studied. As the TNT equivalent increases, the maximum overpressure, displacement and stress on the shell near the liquid level increase. Consequently, the maximum overpressure and displacement on the shell near the liquid level exceed those at the roof-to-shell connection of the tank. In contrast, as the liquid level increases, the maximum stress and displacement first increase near the shell. After reaching the peaks near half filled level, they begin to decrease. Only when the liquid reaches a certain level, it can have an attenuating effect on the overpressure at the bottom-to-shell connection. However, if the liquid level continues to rise beyond a certain threshold, the attenuating effect is no longer prominent. [ABSTRACT FROM AUTHOR]

To design for blast, ballistic or seismic loadings an engineer needs to know the collapse mechanisms of all forms of typical building systems whether residential or commercial in order to have the technical capacity to design against such loadings. Once the engineer becomes aware of the collapse mechanisms that are likely to cause damage through blast loadings that will be applied to a structure by a controlled demolition or an uncontrolled demolition (terrorist attack), a position is reached whereby the design process can commence to not only accommodate the overpressures but also, through design, inhibit or delay collapse so those caught within the building can escape to safety before total collapse occurs. In most such cases death or injury occurs primarily because of the collapse of structures and not because of blast, ballistic or seismic loadings applied to it. In most building systems there are structural entities that are present for specific structural reasons but nevertheless are problematic in that they can inhibit progressive collapse. These problematic structural entities need to be understood in detail and addressed both in controlled and uncontrolled demolitions to be able to achieve a progressive collapse. 3rd world countries see most buildings damaged by the blast, ballistic and seismic loadings as design standards either don’t exist or are not policed by local government instrumentalities thus leading to excessive damage, death or injury. [ABSTRACT FROM AUTHOR]

We study a pure death process. At each discrete time every individual dies or not independently of each other with a constant probability. We give examples showing that in a certain limit extinction happens along a path where one and only one individual is lost at a time. We also exhibit an example for which such a path goes from infinity to 0 in a finite time. This is what we call a process implosion. [ABSTRACT FROM AUTHOR]

An experimental investigation is conducted to study the mechanics of underwater implosion of cylindrical bonded sandwich composite shells. Sandwich structures comprised of concentric carbon-fiber/epoxy shells with PVC foam cores of different densities are imploded in a large-diameter pressure vessel. High-speed photography in conjunction with Digital Image Correlation (DIC) measurements are employed to obtain full-field displacements of the dynamic collapse process. Local dynamic pressure histories are also simultaneously recorded to investigate fluid structure interaction during implosion. Observations of collapse mode, radial displacement and velocity of collapse, interaction between the concentric shells and the foam core and post-buckling failure sequence are made. Increasing foam core shear modulus linearly increases the experimental buckling pressures. Weaker growth of incipient modal deformations are understood to play a pivotal role in obtaining higher critical buckling pressures from bonded sandwich shells than previously studied unbonded sandwich constructions. Three dynamic collapse behaviors as determined by the relative orientation of collapse between the inner and outer shell are observed. Core foam density and imperfections also strongly influence the impulse, energy and pressure pulses released from the implosions. [ABSTRACT FROM AUTHOR]

Abstract The composite materials used at sea are today nearly all based on thermoset resins (polyester, epoxy). However, there is an increasing number of thermoplastic matrix polymers available on the market (PP, PA, PPS, PEEK...), which offer possibilities for forming by local heating, attractive mechanical properties and the potential for end of life recycling. The aim of this study was to design, manufacture and test thermoplastic composite pressure vessels for 4500 m depth, in order to establish a technical, economic and ecological assessment of the use of these materials to replace traditional composites underwater. First, finite element calculations have been carried out to optimize the stacking sequence with respect to the external pressure and buckling resistance. Thick thermoplastic cylinders were then manufactured and tested until implosion, their behaviour showed a good agreement with calculations. Overall, the results show that it is possible to use Carbon/Polyamide 6 (C/PA6) thermoplastic composite cylinders for deep sea applications, as implosion pressures higher than 600 bar (6000 m depth) were achieved. [ABSTRACT FROM AUTHOR]

For an uncontrolled demolition (terrorist attack) explosives are detonated external to a structure primarily but not always. On occasions the terrorist attack is internal to a structure which can also cause the building to collapse. With a controlled demolition (implosion), explosives are always used internal to a building. A building is imploded within its' own design footprint but because of adjacent structures inhibiting it's fall the building might have to be imploded and collapsed outside of its footprint. An oddity is the implosion of a chimney stack. Chimney stacks because of the physics involved can, whilst collapsing, break into two separate pieces which causes concern as the trajectory of fall can then become uncontrollable. Several conditions need to be addressed prior to a demolition as follows: • Is space available to accommodate the debris pile loose volume generated by the implosion? • Is the minimum charge weight of explosives being used? • Will the falling structure cause fragments to impact adjoining structures or can the fragmentation be contained? • Has consideration been given to dust control? • After considering structural details of the building does the structure lend itself to collapse through implosion or should the building be demolished by mechanical means? and • Does the demolition by implosion prove to be more economical and safer than mechanical means? A successful demolition occurs if the conditions above are appropriately addressed and executed. The alternative is to not follow the appropriate conditions and so face three failures that have occurred over the last 20 years in Australia. [ABSTRACT FROM AUTHOR]

Zusammenfassung Ultraschall kann in Flüssigkeiten Lichtblitze erzeugen. Diese Sonolumineszenz stammt aus implodierenden Kavitationsblasen. Das Gas in kollabierenden Blasen kann sich dabei so stark erwärmen, dass kurzzeitig ein Plasma mit blitzartiger Lichtemission auftritt. Aus dem optischen Spektrum des Leuchtens schließt man auf die physikalischen Vorgänge bei der extremen Kompression des Blaseninneren. Dabei zeigen Wolken aus Blasen und isolierte Einzelblasen, die in akustischen Stehwellen gefangen sind, unterschiedliche Eigenschaften. Isolierte Einzelblasen haben eher eine symmetrische Kugelgestalt als die sich gegenseitig beeinflussenden Wolkenblasen. Neuere Arbeiten untersuchen, wie sich im Detail Blasenbewegungen und asymmetrische Implosionen auf die Sonolumineszenz auswirken. Bereits 1935 wurde das Phänomen entdeckt, dass Ultraschall in Flüssigkeiten Lichtblitze erzeugen kann. Das Licht stammt aus implodierenden Blasen. Bis heute sind die Effekte, die zu dieser Sonolumineszenz führen, nicht vollständig geklärt. Mit Untersuchungen des emittierten Spektrums und Hochgeschwindigkeitsaufnahmen versucht man, immer mehr Details zu verstehen. [ABSTRACT FROM AUTHOR]

To design for blast or ballistic loadings a structure is or has been subjected to, a designer needs to be fully aware of all aspects of normal building design systems that will be confronted as well how the mechanism of collapse will or has occurred. Some structures, depending on how they are designed or constructed, possess inherent structural problems that can impede collapse. In the case of a controlled demolition (implosion) prior to the use of explosives RC stairwells should be removed, RC facia with windows removed, all internal cladding and ceilings removed and internal shear walls used to accommodate wind loadings demolished. RC floors should be weakened by removal of sections of the concrete floor matric thus allowing for the formation of plastic hinges when the tensile forces in the floors shift to the reinforcing steel causing it to yield. Everything possible must be done to facilitate collapse and allow gravity to assist in the process. With an uncontrolled demolition (implosion) many factors are unknown during the design process and assumptions must be made. In this case based on past events, explosives and charge weights used must be assumed in advance of an event but nevertheless the design engineer must produce a design that facilitates a delay in collapse long enough for those caught inside the structure to escape to safety. Understanding building design systems in relation to possible collapse and problematic structural elements that could possibly inhibit such collapse are imperatives in designing for and against explosive demolitions. [ABSTRACT FROM AUTHOR]

The end-of-life phase of buildings has not found adequate representation in the literature despite affording opportunities for reclaiming precious construction material and energy savings from the reuse and recycling of demolition waste. Moreover, the extant literature has limited the research focus primarily to the energy analysis of only the building portion, while the associated components, such as mechanical, electrical and plumbing (MEP) services and site features, are generally excluded from study scope. Furthermore, the majority of research studies in this area have excluded the demolition of buildings using controlled explosion. The current study aims to address these research gaps with a view to estimate the demolition energy requirements for the prospective demolition of a recently constructed high-rise residential building, including all connected services and site features. The demolition is executed using a hybrid method comprising deconstruction, mechanical demolition, and controlled explosion. The results indicate that, although building-related sub-systems accounted for approximately 80% of demolition waste and demolition energy requirements, non-building sub-systems, including MEP services, represented a considerable share of about 20% and thus should not be ignored. The overall waste generation rate of the building project is estimated to be about 1715 kg/m2. Concrete contributed to the highest proportions of demolition waste (73.20%) and demolition energy consumption (84.46%), while steel scrap enabled the highest amount of embodied energy recovery (90.46%) in recycling. Overall, the demolition project resulted in the recovery of nearly 2.70% of the embodied energy consumed during the pre-occupation stage of the building project life cycle. The findings of this study are expected to be useful to stakeholders in identifying opportunities to reduce the demolition energy footprint to make the end-of-life stage of a building project more sustainable. The study also establishes the need for emergent policy initiatives on the revision of guidelines for demolition waste management based on the realistic waste generation rate of high-rise residential buildings; the establishment of waste exchanges to reduce landfill space requirements; and incentivizing the use of recycled products in new constructions. Additionally, some relevant areas have been suggested for further research. [ABSTRACT FROM AUTHOR]

In Baudrillard’s view, the post-modern approach - with the dominance of codes, signs and replacing production with consumption in people’s daily life - has started a new process, which has not only resulted in the failure of contemporary man’s motto of individuality and developing opportunities for presenting his demands, but also, in this atmosphere, which is saturated with signs from media; art, politics, religion and economics, as separate and concrete areas, have lost their outer reality and have disappeared in the horizon of media’s dominance together with the concept of subject. According to Baudrillard, this approach is in the shape of game and is made up of general concept of art. With this difference, that art is no longer defined as a realm separate from politics, religion and economics, art is, in a general sense, transmuted into a style and method, in light of which, ugly and beautiful, good and bad, right and wrong are departed from their references (authorities) such as ethics, religion, economics and work of art and pass out in the end of the route together with the concept of subject.