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The aim of this study is to evaluate the frequency and the distribution of symptoms and complications of oculocutaneous and respiratory systems among the individuals with a history of toxic exposur...

Background: Tooth wear is the loss of tooth structure from physical or chemical attack of nonbacterial origin. Predominant causative factor for tooth wear in primary dentition is erosion. This study was conducted to assess the prevalence of tooth wear and its associated factors in primary dentition.Methods: Analytical cross-sectional study was conducted after obtaining ethical approval among 425 children aged two to 12 years, enrolled in different preschools/schools located in Kathmandu valley. Informed consent from parents as well as assent from children were obtained. Oral examination for assessing tooth wear was done using Smith and Knight Tooth Wear Index. Self-administered questionnaires were sent to parents for considering the factors associated with tooth wear. Data were entered in Microsoft Excel Sheet and analysed in Statistical Package of Social Sciences. The chi-square/fisher’s exact test was done to establish the association between tooth wear and various factors.Results: Among total participants, 295 (69.4%) had tooth wear in at least one or more teeth. Tooth wear was seen significantly higher in children with increasing age (p

Precise online identification of safe-zone evolution has been long desired in the context of indoor chemical attack events. Computational fluid dynamics (CFD) technology can provide great accuracy but is incapable of applying on online predictions of a large-scale fluid system due to the enormous computational costs to date. In this paper, we propose a Multi-Step Spatial-Temporal Situational-Awareness Network (MSSTP-SA Net) based on deep learning algorithms for rapid online estimation of concentration field. The dataset is firstly created by CFD simulation considering different poisonous gas release and decontamination scenarios in pre-specific domain with various combinations of airflow conditions and source parameters. Corresponding experiments are also provided for validations. The test experiments of the trained network suggest that the evolution of concentration field's distribution can be predicted faithfully in millisecond computation time costs. We hope this approach to be highly useful in most chemical attack scenarios to reduce casualties.

Painting provides better attraction and protection to the building. It is used for preventing the chemical attack, ultra virus light, protecting from extreme solar and moisture even it able protect from germs There are different types of brands are also playing the predominant role in the field of painting. Even the non-skid protective paint coatings are also used by the modern house to prevent slipping, while some exterior paints are used as attractive in the eyes of people. In general, the paints are protecting the building as well as attracting the people to have a positive opinion on the house. At this juncture, the research in this field is adding some extra feather to this painting industry. The present study is focused on to analyze the various factors which are influencing the consumer’s influence on purchase decision. At this juncture, the paint manufacturing companies are putting all efforts to hold the greater market share, it is very important to analyze the brand perception of consumers and their final purchase.

Chemical agents of warfare are divided into lung agents, blood agents, vesicants, and nerve agents. Intensivists must familiarize themselves with the clinical presentation and management principles in the event of a chemical attack. Key principles in management include aggressive supportive care and early administration of specific antidotes, if available. Management includes proper personal protection for critical care providers. Patients may make complete recovery with aggressive supportive care, even if they appear to have a poor prognosis. Hospitals must have an emergency response disaster plan in place to deal with all potential causes of disasters, including illnesses resulting from chemical agents.

Droplets microfluidics is broadening the range of Lab on a Chip solutions that, however, still suffer from the lack of an adequate level of integration of optical detection and sensors. In fact, droplets are currently monitored by imaging techniques, mostly limited by a time-consuming data post-processing and big data storage. This work aims to overcome this weakness, presenting a fully integrated opto-microfluidic platform able to detect, label and characterize droplets without the need for imaging techniques. It consists of optical waveguides arranged in a Mach Zehnder’s configuration and a microfluidic circuit both coupled in the same substrate. As a proof of concept, the work demonstrates the performances of this opto-microfluidic platform in performing a complete and simultaneous sequence labelling and identification of each single droplet, in terms of its optical properties, as well as velocity and lengths. Since the sensor is realized in lithium niobate crystals, which is also highly resistant to chemical attack and biocompatible, the future addition of multifunctional stages into the same substrate can be easily envisioned, extending the range of applicability of the final device.

Background In 2014, Hama Governorate was exposed twice to chlorine gas, with 15 patients presenting to Kafr Zita Hospital in Northwest Syria. This study aimed to describe clinical manifestations of chlorine gas exposure to identify factors leading to facility admission and the need for ICU/intubation in conflict-affected areas with limited healthcare infrastructure. Methods We conducted a case-series study, using medical records of suspected chlorine-exposed patients presenting at Kafr Zita Hospital on either 11 April or 22 May 2014. Data on age, sex, initial clinical presentation, therapeutic management, and outcome were compared by hospital admission/non-admission and attack date. All patients provided verbal informed consent. Results Fifteen patients with signs of chlorine gas exposure had detailed medical records. The mean age was 25.7 years (range 2-59), eight were male (53%), and three (20%) were under age 16. At initial presentation, all experienced respiratory distress, due to severe airway inflammation confirmed by nonspecific pulmonary infiltrates on chest x-ray, and similar intestinal, neurological, dermatological, ophthalmological, and psychological signs and symptoms. Acute management consisted of oxygen and bronchodilators for all patients, hydrocortisone (93%), antiemetics (80%), and dexamethasone (13%). Seven (47%) made a rapid symptomatic recovery and were discharged the same day and eight (53%) were admitted for a median of two days (range 1-6 days), one of whom required intubation and later died. The only significant associations found were higher mean pulse rate (i.e. 138 versus 124; p=0.043) and body temperature (37.0 versus 36.5; p=0.019) among admitted patients compared to non-admitted. Conclusion Our results demonstrated that even in low-resource humanitarian settings the survival rate for chlorine gas exposed patients is fair. Despite the small sample, this study provides insight into the clinical presentation, management, and outcomes of weaponized chlorine gas exposure, though further research is required to understand any chronic consequences.

The article focuses on the basic security aspects of population protection against chemical terrorism. The introduction is focused on the definition of security and the general characteristics of security documents. The last passages of the texts are focused on publishing the issue of terrorism, ensuring a special approach to the subject of the article put on the field of chemical terrorism, and the theory of the protection of the population against chemical terrorism. The introductory part of the article describes the various means of chemical terrorism, the threat of part of the weapons is presented in the fight against chemical substances. Greater risk can be applied to chemicals that are available to the advertiser for modeling in the TerEx software program. The conclusion of the article is a sign of evaluation of population protection and submission of its proposals for possible improvement of the current situation. instructions give you basic guidelines for preparing camera-ready papers.

Background: Medical defense against chemical, biological, radiological, and nuclear (CBRN) threats should be established through systematic education in college and career development training to counter the response successfully. Methods: Taking the course of Medical Countermeasures against CBRN Weapons is compulsorily for all military medical students in the Chinese People’s Liberation Army (PLA). In the present study, a modularized course for field training of Chemical Defense Medicine is provided, which is an important part of the Integrated Military Medicine Exercise (IMME) conducted annually in PLA military medical university. Discussion: The established modules are functionally designed as passing through a contaminated area with protective posture, operating chemical defense equipment, battlefield rescue after a chemical attack, and early treatment of chemically contaminated casualties. This modularized training is task-oriented, function-based, and integrate with a functional drill, which provides an example in the training of CBRN defense medicine.

3D printing (ranging from technology to materials) for additive manufacturing are receiving increased attention in the scientific and technical literature. More specifically, 3D printers (getting progressively cheaper) and properties of the starting printing materials (e.g., mechanical strength, electrical insulation, resistance to chemical attack) are particularly important for many chemistry-related applications. In this paper, 3D printing technology and materials will be reviewed in some detail. Limited examples from the author’s laboratory will be reported. Chemistry and bio-related applications of 3D printing will be outlined and possible future directions will be suggested.

The CMP challenges for advanced technology nodes are discussed. Global and local uniformity challenges and their cumulative effects are presented. Uniformity improvements for advanced node integration were achieved through slurry, pad and platen optimization, innovative integration schemes, the reduction of incoming variation and the reduction of cumulative effects. We discuss reduction of typical CMP defect types. Defects resulting from simple mechanisms (foreign material, polish residues) and those resulting from chemical and physical interactions (corrosion, chemical attack, scratches, physical migration) and strategies for control are studied. Defectivity reduction measures include new post-CMP clean chemicals, new slurries and pads and reduction of incoming defectivity. Finally we discuss an observed tradeoff between good defectivity and good uniformity.

Accurate prediction of hygrothermal behavior in the concrete is vital requirements to make more realistic service-life extension decisions. In this work, a neural network based hygrothermal prediction model to estimate a temporal hygrothermal condition in surface-protected concrete facade members is developed and presented. The model learns the case-specific features of hygrothermal behavior using the two years temperature and relative humidity data obtained from the installed probes. The performance evaluation confirms that the model describes the hygrothermal behavior inside the concrete facade with a high accuracy. This in turn enables to assess the corrosion rate as well as deterioration risk levels caused by frost and chemical attacks while identifying the appropriate surface protection system.

An overview and a comparative analysis of existing methodologies adopted in the US and in Europe for the assessment of risks posed by intentional attacks against industrial sites, and more specifically chemical facilities where relevant quantities of hazardous substances are stored or processed, are given. Two case studies were analyzed by the ANSI/API RP 780 and the VAM-CF methodologies. The results show that the VAM-CF methodology resulted to be more conservative with respect to the API methodology for low-risk scenarios. The API methodology resulted more suitable for practical application, in particular for analysts having limited experience.

Objectives: Public transport vehicles (PTVs) play a decisive role in development of the urban economy. However, the safety of PTVs is threatened by the man-released chemical or arson attack. It was found that indoor air safety can be greatly improved by employing air-rain ventilation instead of the common ventilation in a PTV. Methods: Numerical simulations and experiments have been done to prove the effectiveness of the air-rain flow against chemical attack or arson in PTVs. Results: The research shows that, during a chemical attack, an air-rain flow of 0.1 m/s can constrain the spread of a chemical agent in a very limited zone near its source, which is far away from the passengers’ breathing area in the PTV. During an arson attack, at an air-rain flow of 0.3 m/s, most of the area in the PTV maintains a low temperature for at least 60 s during a fire, which is long enough for passenger evacuation. Conclusion: Compared to common ventilation, the key characteristic of air-rain ventilation is its resistance to the blending effect of the air. Because of this, the spread of chemical agents, hot gas/combustion products during a fire, and fuel aerosol is constrained to a limited area in a PTV. Passengers are then protected from chemical attack, explosion of fuel aerosols, and high temperatures and smoke. Thus, we can say that this new ventilation mode increases passenger safety in buses.

PET - poly (ethylene terephthalate) - bottle surfaces were exposed to chemical agents and evaluated with middle infrared spectroscopy (MIR) and near infrared hyperspectral imaging (HSI-NIR). Images (928-2.524 nm) were acquired at different times from bottle surfaces exposed to alkaline, acidic and ethanolic media. Savitzky-Golay smoothing (2nd order polynomial and 5-point window) combined with Standard Normal Variate (SNV) was used for pre-processing data. Scores from principal component analysis (PCA) on images showed discrimination of PET according to exposure time, particularly when employing NaOH. After the first two hours of chemical exposure, significant contribution of the (-C-O + OH) combination band indicated formation of glycol ethylene on the PET surface, which was confirmed from PCA loading plots. MIR reflectance spectra ranged from 4.000 to 650 cm-1. Changes in spectral intensities could be associated with depolymerization of PET when exposed to NaOH. These were confirmed with PCA and attributed to the carboxylate group of terephthalate.

A method is presented to investigate highly localized micro-damage phenomena during cyclic crack initiation in structural steel S355. For this purpose, notched samples are loaded in the finite life range. The surface of the notched specimen is inspected with a speckle interferometer (ESPI), a high-resolution and full field sensor for strain measurements. The measurements are taken in intervals of a few hundred load cycles. The results show a localization and accumulation of strain with increasing material damage. The presented work is part of the DFG research programme Graduiertenkolleg 2075 “Modelling the constitutive evolution of building materials and structures with respect to aging”. This has set itself the goal of describing and evaluating the constitution of structures and materials under mechanical loading and chemical attack with respect to different spatial and temporal scales.

© 2015 Elsevier Ltd. Abstract Process- and chemical plants may constitute a critical target for a terrorist attack. In the present study, the analysis of industrial accidents induced by intentional acts of interference is carried out focusing on accident chains triggered by attacks with home-made (improvised) explosives. The effects of blast waves caused by improvised explosive devices are compared with those expected from a net equivalent charge of TNT by using a specific methodology for the assessment of stand-off distances. It is demonstrated that a home-made explosive device has a TNT efficiency comprised between 0.2 and 0.5. The model was applied to a case study, demonstrating the potentiality of improvised explosives in causing accident escalation sequences and severe effects on population and assets. The analysis of the case-study also allowed obtaining suggestions for an adequate security management. publisher: Elsevier articletitle: Vulnerability of industrial facilities to attacks with improvised explosive devices aimed at triggering domino scenarios journaltitle: Reliability Engineering & System Safety articlelink: http://dx.doi.org/10.1016/j.ress.2015.03.004 content_type: article copyright: Copyright © 2015 Elsevier Ltd. All rights reserved. ispartof: Reliability Engineering & System Safety vol:143 pages:53-62 status: published

In verschiedenen Anwendungsgebieten ist der Baustoff Beton hohen Beanspruchungen von ausen, z. B. durch betonaggressive Wasser, ausgesetzt, die die Dauerhaftigkeit des Bauwerks beeintrachtigen konnen. Fur einen chemischen Angriff in naturlichen Boden und Grundwassern bestehen normative Vorgaben, um den Angriffsgrad anhand der Art und Konzentration der angreifenden Stoffe in Expositionsklassen einzustufen. Ob und inwieweit die Einstufungen fur Boden und Grundwasser auch auf andere Bereiche mit chemischem Angriff auf Beton, z. B. Kraftwerksbau, Abwasseranlagen, Biogasanlagen etc., zu ubertragen sind, ist stets im Einzelfall zu uberprufen. Um Beton mit einem fur die jeweilige Exposition adaquaten chemischen Widerstand auszustatten, sind in der Regel die betontechnologischen Vorgaben der einschlagigen Regelwerke ausreichend. Bei besonders starker Beanspruchung werden daruber hinaus zusatzliche Masnahmen erforderlich, die sowohl die Betontechnologie als auch die Bauausfuhrung betreffen konnen. Uber die Art und den Umfang solcher im jeweiligen Anwendungsgebiet zusatzlich erforderlichen Masnahmen wird in der Fachwelt kontrovers diskutiert. Diese Problemstellungen in der Praxis aufgreifend, hat der Deutsche Beton- und Bautechnik-Verein E.V. neue Arbeitshilfen herausgegeben, in denen auf die derzeitige Vorgehensweise bei der Bewertung des chemischen Angriffsgrads in unterschiedlichen Anwendungsgebieten des Betonbaus und bei der Festlegung geeigneter Schutzprinzipien eingegangen wird. Concrete structures under chemical attack – new DBV Guide to Good Practice In various fields of application concrete is highly stressed by the environmental exposure, e. g. by aggressive water, which may affect the durability of the structure. There are normative guidelines dealing with the chemical attack in natural soil and ground water which allow a classification of the attack in exposition classes on basis of the type and concentration of the corrosive substances. Whether and to what extent the classification criteria for soils and groundwater are transferable to other areas with chemical attack on concrete, e. g. power plants, wastewater treatment plants, biogas plants, etc. must always be checked individually. In order to provide concrete with an adequate chemical resistance, the requirements for the concrete technology according to the general standards and regulations are usually sufficient. For particularly high stresses additional measures are needed which can affect both the concrete technology and the construction. A controversial debate among experts exists with respect to the type and extent of such measures required in the respective field of application. With focus on these practical issues, the German Society for Concrete and Construction Technology (DBV) has published a new Guide to Good Practice which provides the common procedure for the evaluation of a chemical attack on concrete in different fields of application and deals with appropriate protection principles.

Reactive powder concrete (RPC) is one type of advanced cementitious composite that has been increasingly used. Its high mechanical strength enables the application of the composite in bolder structures. Considering its recent history of use, there is a lack of knowledge about this materials durability. Therefore, this paper aimed to evaluate the behavior of hybrid fiber reinforced RPC under accelerated testing, evaluating different hybrid fiber combinations. Composites contained metallic microfibers and polypropylene fibers in the following proportions: 100/0%, 75/25%, 50/50%, and 0/0% (metallic/polypropylene). Accelerated tests were performed (salt spray, carbonation and acid immersion), as well as 3D microtomography analyses, in order to visualize the distribution of fibers throughout the matrix. Results indicated high durability under some aggressive wet environments, with no signs of carbonation, nor damage caused by salt spray, and small damage related to sulfuric acid attack. In addition, it was possible to observe in the 3D microtomography images that fibers are well distributed in the matrix volume, and that there is no transition zone in the material due to the reduced volume void. Keywords: Reactive powder concrete; Chemical attack; Durability; Deterioration; Fibers hybridization.

Despite the biocompatibility and perfect aesthetics of dental ceramics, failures are still of considerable concern because of some problems that are clinically experienced. There is limited information about the retentive strength of luting agents for zirconium oxide-based crowns. On the market there are different types of cements that are available for fixating of zirconia restorations. So far there is no consensus regarding the best protocol for zirconia luting used in dentistry. Zirconia core-based ceramics are highly resistant to chemical attack from hydrofluoric acid and a different approach is required if clinician elects to bond these restorations using resin-based adhesives and luting cements. Optimal surface preparation is mandatory to ensure clinical success when cementing\luting a zirconia restoration. Although zirconia for dental restoration is used already for decades, the best method to ensure a stable bond between the zirconia and tooth structure is still questionable.

Qin, F.-Y.; Liu, T.-X.; Yang, F.-L., and Liu, H.-B., 2019. Simulation on aseismic behaviors of reinforced concrete corroded in marine environment. In: Gong, D.; Zhu, H., and Liu, R. (eds.), Selected Topics in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 94, pp. 21–25. Coconut Creek (Florida), ISSN 0749-0208.With the acceleration of the economic development, people has more and more demand on reinforced concrete, a kind of building materials, whose properties directly affect the security and reliability of architectural entities. However, reinforced concrete that has long been submerged in the marine environment not only has to bear various loads such as wind and rain, but also suffer from physical and chemical corrosion, which in turn worsens its durability, degrades its mechanical properties, and badly destroys practical properties of marine works. To accurately evaluate how the aseismic behavior of reinforced concrete frame structures in the marine environment is subjected to change with chemical attack, this paper adopts the ABAQUS, a finite element software, to simulate and compare aseismic behaviors of an immersed tunnel structure newly built and after withstanding 60 years of chemical corrosion in the marine environment. The findings show that chemical corrosion in the marine will greatly degrade the aseismic behavior of reinforced concrete structures, providing a theoretical basis for qualitative evaluation on the impact of chemical corrosion on aseismic property of reinforced concrete frame structures.

Failure analysis is a process of gathering facts, making observations, and collecting analytical data to determine how a component failed. The subsequent step involves applying engineering principles to define why the failure occurred and what should be done to prevent recurrence.

During the last years, 3d printing for rapid prototyping using additive manufacturing has been receiving increased attention in the technical and scientific literature including some Chemistry-related journals. Furthermore, 3D printing technology (defining size and resolution of 3D objects) and properties of printed materials (e.g., strength, resistance to chemical attack, electrical insulation) proved to be important for chemistry-related applications. In this paper these are discussed in detail. In addition, application of 3D printing for development of Micro Plasma Devices (MPDs) is discussed and 2d-profilometry data of a 3D printed surfaces is reported. And, past and present chemistry and bio-related applications of 3D printing are reviewed and possible future directions are postulated.

This article discusses the different effects of the operating environment on polymers when they are subjected to both static and dynamic loads. It discusses ageing mechanisms – for example, oxidation, thermal degradation, chemical attack and plasticisation – which can occur during service and it looks at the test methods that are available to characterise performance.

This paper presents one possible way of deploying detachments for neutralizing the effects of chemical attacks in a brigade defense zone. The detachment composition is provisional and depends on the assessment of whether the enemy in the incoming combat will use weapons of mass destruction. A detachment consists of several organizational units: medical care forces, chemical reconnaissance forces, forces for the establishment of combat efficiency and chemical decontamination forces. The capabilities of the mentioned forces depend on their size, equipment, training level, extent of effects and combat conditions. The paper indicates a potential to overcome the gap in the provisions after disbanding the Army Corps.

Structures experience various types of loads along their lifetime, which can be either static or dynamic and may be associated to phenomena of corrosion and chemical attack, among others. As a consequence, different types of structural damage can be produced; the deteriorated structure may have its capacity affected, leading to excessive vibration problems or even possible failure. It is very important to develop methods that are able to simultaneously detect the existence of damage and to quantify its extent. In this paper the authors propose a method to detect and quantify structural damage, using response transmissibilities measured along the structure. Some numerical simulations are presented and a comparison is made with results using frequency response functions. Experimental tests are also undertaken to validate the proposed technique.

Corrosion modifies the steel-concrete interface in reinforced concrete structures. Moreover in structures subjected to cyclic load, a simultaneous mechanical deterioration due to the load is present. Both phenomena can lead to an evolution of cracks width during the service life. In order to evaluate the crack openings increase, an experimental campaign on reinforced concrete ties subjected to simultaneous loading and corrosion have been realized. Transversal crack opening, initially due to loading and longitudinal corrosion cracks evolution is monitored. Results highlight the differences in terms of corroded and uncorroded specimens, static and cycling test and also different loading amplitude. Finally it can be observed as the growing of the damage is significantly different when a cycling action, combined with a chemical attack is present.

A device consisting of poly allyl diglycol carbonate (PADC) foils with a polyethylene and polyvinyl chloride (PVC) radiator was calibrated in order to perform the dosimetry of an 241Am-Be source covering a dose range from 0 to 3.1 mSv. Working conditions were established for a good visualization and counting of tracks: chemical attack was made in two steps with different solutions and etching times. A good fit was obtained for the dose as a function of the number of tracks per unit surface area. The calculated decision threshold was 0.12 mSv.

The worldwide shift towards performance-based standards for concrete demands the advent of performance tests that combine more than one damage mechanism. Such tests can be more reliable in evaluating emerging concrete types such as self-consolidating concrete (SCC). Several applications of SCC involve its exposure to both freezing–thawing cycles and chemical attack, particularly to sulphate-rich media. This study aims at investigating the durability of SCC to sulphate attack coupled with frost action. Potential performance risks of SCC under this dual exposure were identified in terms of various mixture design parameters. Deterioration in physico-mechanical parameters was related to thermal, mineralogical and microscopy analyses, which demonstrated the complex mutual effects of sulphate attack and frost action on SCC specimens. It is shown that SCC mixtures that perform well under the classical ASTM C 1012 test can fail under coupled exposure to freezing–thawing cycles and sulphate attack.

The objective of the study was to examine the effects of five plastic coatings on cleanability of concrete flooring. In the laboratory it is easier to use simplified model soils (dirts) than actual soils present in piggeries. The aim of the study was particularly to examine the correspondence between the cleanability of the surfaces using simple model soils in a radiochemical reference method and manure soil in a colorimetric study. According to both colorimetric and radiochemical measurements, coating of concrete improved the cleanability of the flooring. The use of coating can thus be justified in sites in which a high cleanness level is required, probably meaning that coatings will be used only in some sites in animal production buildings. According to the colorimetric results, coating also decreases the time required for cleaning. As an important result for further studies concerning comparison of surface materials for animal buildings, this study demonstrated that cleanability of the surfaces from manure soil could be described by both 14 C- and 51 Cr- labelled radiochemical model soils (correlation coefficients 0.656 and 0.691, respectively). The quantitative radiochemical method is an excellent way to detect soil absorbed in materials. This is important especially from the point of view of durability, because soil absorbed in the flooring material causes chemical attack, which weakens the material in the long run.

This paper presents findings from microanalytical investigation conducted on disintegrated concrete that had been used to construct a weir within a coal mine in South Africa. The concrete was in contact with polluted mine water, commonly referred to as acid mine drainage (AMD). Accordingly, the weir had been exposed to AMD decant which led to disintegration of concrete due to chemical attack. Investigations were conducted by optical microscopy (OM), scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD). The field samples examined consisted of soft, broken concrete chunks and a whitish powdery substance that had crystallised and formed a surface coating on certain cracked locations on the deteriorated concrete. No evidence of pyrite oxidation was found in the investigation. The observed deterioration is discussed in relation to acid attack mechanism and its possible co-existence with external sulphate attack process.

One of the most severe environments that concrete structures can experience is that of marine exposure in northern, temperate regions. The concrete will be subjected to freeze–thaw cycles, wave action, cycles of wetting and drying, ice abrasion and chemical attack by seawater. For such structures to have an extended service life, careful attention must be paid to all phases of the project, including proper structural design, choice of materials, concrete mix design, mixing, placing and curing of the concrete and appropriate post-construction monitoring. The 12.9-km-long Confederation Bridge, which links the Canadian provinces of Prince Edward Island and New Brunswick, is the longest in the world crossing ice-covered water. It provides an excellent example of how this can be achieved.

In 2001 Japan Society of Civil Engineers (JSCE) published its first Standard Specifications for Concrete Structures - 2001 "Maintenance", which is the first ever specification that covers every maintenance aspect of concrete structures. The Standard Specification consists of two parts; Part 1: Maintenance and Part 2: Standards for Maintenance. The first part includes required performance, basic principles for maintenance, inspection, identification of deterioration mechanism, evaluation of structural performance, and remedial measures together with a flowchart outlining the overall maintenance activities from initial inspection (birth/rebirth certificate) to execution of remedial measures. The second part provides detailed information on deterioration prediction, inspection methods, evaluation/judgment and remedial measures for different deterioration mechanisms in separate chapters. Seven types of deteriorations, namely carbonation induced deterioration, chloride induced deterioration, frost damage, chemical attack, alkali aggregate reaction, fatigue of slabs, and fatigue of beams are covered.uBesides "Maintenance", JSCE also published the Standard Specifications for Concrete Structures "Structural Performance Verification", "Seismic Performance Verification" and "Materials and Construction". The whole set of Standard Specifications, adopting the performance-based concept, provides standard specifications for structural design, materials, construction, maintenance and repair to satisfy the required performance during the design life taking into account chronological change in the structural performances. This paper introduces the JSCE Standard Specifications "Maintenance" and presents briefly some new issues to be introduced in the next version of "Maintenance" as well as application examples illustrating maintenance plans of a superstructure of open-type wharf. (A)

The present paper discusses the process development and optimisation conducted over a two-year period at the continuous caster at Columbus Stainless to allow an increased sequence length, thereby satisfying the continual drive for increased throughput, lower cost of production and higher quality. Increased sequence length results in longer exposure of refractory to steel or slag resulting in more erosion and chemical attack. The refractory system in use at Columbus Stainless was initially designed and optimised for 6 h of casting and the focus of the development was to increase this time to 14 h. This objective was achieved by modifications to tundish design and lining, optimisation of the tundish cover, modifications to stopper and SEN design, composition and operating practise. After these changes, the original objective of increasing the sequence length to 14 h was achieved with a concomitant saving in refractory cost per ton of up to 35%.

Ceramic materials are notable for their rigidity, insulation and resistance to hostile environment. Nevertheless, if a stressed ceramic component is exposed to chemical attack, it may suffer from a form of delayed fracture known as static fatigue. From the point of view of a designer, it is clearly desirable to determine the behavior of sub-critical crack growth; the crack path and crack growth rate, as a function of material properties and loading conditions are of particular interest. This paper presents a review of advances in stress assisted corrosion problem in history and its corresponding numerical approaches in the last decades, and finally, comes up with consideration and crucial suggestions for future work.

A glass melter for use in processing radioactive waste is a challenging environment for the materials of construction (MOC) resulting from a combination of high temperatures, chemical attack, and erosion/corrosion; therefore, highly engineered materials must be selected for this application. The focus of this report is to review the testing and evaluations used in the selection of the Defense Waste Processing Facility (DWPF), glass contact MOC specifically the Monofrax® K-3 refractory and Inconel® 690 alloy. The degradation or corrosion mechanisms of these materials during pilot scale testing and in-service operation were analyzed over a range of oxidizing and reducing flowsheets; however, DWPF has primarily processed a reducing flowsheet (i.e., Fe2+/ΣFe of 0.09 to 0.33) since the start of radioactive operations. This report also discusses the materials selection for the DWPF off-gas system and the corrosion evaluation of these materials during pilot scale testing and non-radioactive operations of DWPF Melter #1. Inspection of the off-gas components has not been performed during radioactive operations with the exception of maintenance because of plugging.

An elementary constitutive model to describe the behaviour of bonded soils or soft rocks subject to mechanical and/or chemical degradation is presented. To limit formalism as much as possible, the original Cam Clay model is taken as a starting point and axisymmetric conditions are considered. The effect of grain bonding is taken into account by one parameter that decreases with increasing strains and amount of chemical attack. Comparisons with experimental data in laboratory tests are shown together with two applications.

Laboratory techniques employed for cleaning marine sediments for quantitative diatom analyses are time consuming and expensive. In an attempt to reduce preparation time, the method in use in our laboratory, has been compared to six other different methods, which derive from Barron's procedure for rapid sample preparation at sea. Based on the statistical analyses of the results all the methods in which centrifugation was used, were eliminated. From the two methods that did not show differences from the control method, the cleaner and better preservation of the diatom specimens observed in the slides produced by method M2 lead us to elect this procedure as the best. This method distinguishes itself from other techniques in using of a non-dried sample dispersed before the chemical attack.

The thaumasite form of sulfate attack (TSA) has received considerable research attention since its discovery in several motorway bridge foundations in the UK in 1998. Its significance as a deterioration mechanism in concrete, leading to the fluidisation of the matrix in extreme cases, is now acknowledged. Despite the continuing uncertainties that exist with regard to mechanisms for thaumasite formation, there is now reasonable agreement on conditions that favour TSA, and, as with all deleterious reactions affecting concrete structures, there is a desire to be able to anticipate the likelihood of occurrence so that such problems can be ‘designed out’ in the formulation stage. Inevitably, this points to the development of suitable models and the generation of reliable data. It is towards this latter goal that this paper is focused. Building on our previous studies, which reported on the means of fixing intermediate compositions in the ettringite–thaumasite solid solution series, this paper describes the treatment of solubility data, which can be utilised in phase development and solubility models involving this system.

Recent events including the Sept. 11, 2001 attacks in New York, Washington, DC, and Pennsylvania have illustrated the vulnerability of the United States to terrorist activity. Many experts agree that a chemical or biological event is likely to occur within the continental United States during our lifetime. The anesthesiologist, as well as, emergency medicine provider and critical care specialist will represent an integral part of the initial recognition and medical response to such an attack. A modern chemical attack on the United States could involve many differing agents including: nerve agents, vesicants, cyanide compounds and pulmonary irritants. In this situation, the anesthesiologist will be in the unique position to respond and treat affected patients. Physicians trained in anesthesiology possess expertise and knowledge in a variety of areas including airway protection, ventilation, oxygenation, pharmacology, cardiovascular physiology and pulmonary physiology. It is this training which gives the anesthesiologist the flexibility to respond to a chemical threat more effectively than most other medical specialties. We present a history of chemical warfare as practiced in the modern era. Comprehensive coverage of all chemical agents would be beyond the scope of this paper, therefore we will focus on the development and history of the major chemical agents.

Nerve agents are perhaps the most feared of potential agents of chemical attack. The authors review the history, physical characteristics, pharmacology, clinical effects, and treatment of these agents.

Of all the components that compose a highway bridge, the bridge deck usually deteriorates the most quickly and requires the most maintenance and repair because of its exposure to detrimental conditions. Several preventive maintenance techniques are available to retard bridge deck deterioration and thus prolong service lives. Of these techniques, types of bridge deck overlays are investigated. As preventive maintenance, an overlay provides a protective layer between the bridge deck and the detrimental conditions that promote deterioration. In general, this protection enhances the material properties of the overlay, which may include low permeability and resistance to chemical attack as well as added thickness. The overlay procedures used for bridge decks in Tennessee are investigated from information about overlay types and their usage obtained through several sources, including interviews with Tennessee Department of Transportation personnel who are experienced in bridge maintenance. Four types are identified: asphalt, reinforced portland cement concrete, nonreinforced polymer-modified concrete, and thin bonded overlays. Each overlay is described and typical applications, bridge deck preparation, general construction techniques, special considerations, expected service lives, and average costs are discussed. Expected service lives ranged from 15 to more than 30 years, and average costs ranged from $30 to more than $100 per square yard. All overlay types are useful and appropriate under different situations.

Introduction Over the past five years, events in the Middle East have increased the awareness about the possible use of chemical weapons and their surrogates, the so-called “toxic industrialized compounds”. The major issue is to identify on a clinical basis the likelihood of exposure to chemicals ranging from riots agents to lethal agents in order – to advice protection of rescuers and care givers at the scene – to provide adapted treatment to casualties, and; – to address the need for antidote supply. Patients and methods Systematic review of the literature on acute chemical accidents resulting in casualties to identify easily collected clinical signs and symptoms resulting. This review provided a limited list of signs to be collected in a small subset of frankly symptomatic patients. The signs and symptoms were classified according to the corresponding organ(s) involved by chemical injury. All signs shoud be clinically collected using current physical examination. There are presently three versions of the sheet: French, English, and Arabic. Owing to the political context and analytical difficulties, we never attempted at determining the agent having caused signs and symptoms. Results The one-page questionnaire was used in 5 settings, including – a chemical incident related to the opening of a chemical plan in Lumumbashi in 2011; – the repeated use of anticholinesterasic agents towards civilians in Syria from April 2013 up to that the attack launched the 21st of August 2013; – repeated chlorine attack towards civilians in Syria since March 2014; – an attack using a vesicant agent towards civilians in August 2015 in Syria, and; – the acute onset of paraplegia in Mali on Summer 2015. In each setting, the analysis of the quoted items on the sheet allowed to suggest the class of the toxicant within a few hours after exposure. In the case of exposure to chlorine and to the vesicant agent, two collections of signs over a period of a few hours were needed to draw definitive conclusion. The lowest number of casualties in an exposure was three after exposure to vesicant agents. The definitive diagnosis was in accord with the initial presumption regarding the class of toxicant. Early identification allowed to advise adapted protection of caregivers at the site as well as define the need for antidote supply and the nature of the antidote. Conversely, in one setting (Mali 2015) a toxic origin was ruled out as not fitting any known toxicant while an infectious disease was identified as the likely cause of the outbreak. Discussion In case of incident, a one-page sheet of the list of signs and symptoms allowed to define a toxidrome specific of a class of toxicant, helped in protecting rescuers and care givers and refined the needs for supportive and antidotal treatment. Repeated collection of signs may be required in agents acting over hours. A close collaboration with a skilled toxicologist is needed when facing incident involving hazardous materials. At the scene only chemical incident was identified. However, repetition of bombing in the same area resulted in a more accurate and rapid medical response. Conclusion A one-page sheet easily filled out at the scene in the context of chemical incident allowed defining the toxidrome and consequently protection of rescuers, needs for supportive and antidotal supply. Owing to the rapidity of action of a number of toxicant a single or repeated examination over a few hours is needed to define the toxidrome and therefore the class of toxicant.

This chapter presents the main aging and failure mechanisms of stator windings, as well as the options associated with each mechanism for repairing the stator or altering its operation to extend winding life. The only failure mechanisms discussed here are those that are due to gradual aging of the winding. Some of the failure mechanisms will only occur on form-wound stators, and some only in random-wound stators. However, many of the failure processes can occur in either type of stator. The chapter discusses the relevance of the failure process for both random-and form-wound stators. The symptoms for each failure mechanism are also described.

o M ecent events including the September 11, 2001 attacks in New York, Washington, DC, and ennsylvania have illustrated the vulnerability of he United States to terrorist activity. Many experts gree that a chemical or biological event is likely o occur within the continental United States durng our lifetime. The anesthesiologist, as well as he emergency medicine provider and critical care pecialist, will be integral to the initial recognition nd medical response to such an attack. A modern chemical attack on the United States ould involve many different agents including As, vesicants, CN compounds, and pulmonary rritants. In this situation, the anesthesiologist will e in a unique position to respond and affect paient outcome. Physicians trained in anesthesiology ossess expertise and knowledge in a variety of reas including airway protection, ventilation, oxgenation, pharmacology, CV physiology, and ulmonary physiology. It is this training that gives he anesthesiologist the flexibility to respond to a hemical threat more effectively than most other edical specialists. We present a history of chemical warfare as racticed in the modern era, focusing on the deelopment and history of the major chemical gents. Aspects of chemical agent insults in the erioperative setting, an area of particular interest o the anesthesiologist, are described.