Physical Decay Research Articles

To lift or not to lift? The dilemma of an aging face in Erica Jong's later works

Resistance to physical decay and the desire to keep youthful looks are not new in human history. Today, however, anti-aging discourse intensifies the longing to reshape one's body and stop the ravages of time. Aging is often portrayed as a personal accountability, a sign of moral responsibility, and even disease, which affects older women disproportionately. In order to adjust to contemporary beauty standards, many older women decide to undergo various rejuvenation procedures. However, few studies on the outcomes of such cosmetic interventions in relation to aging, acceptance and self-perception exist. This article addresses American writer Erica Jong's concerns about the aging body and surgical anti-aging interventions. As spokeswoman of the American post-war generation, the author shows how facial rejuvenation procedures generate conflicting feelings, and reminds her readers that older women continue to be doubly marginalized in today's youth- and beauty-driven society.

IMPLEMENTATION OF THE SOVIET AUTHORITIES OF THE ANTI-RELIGIOUS POLICY STATE SECURITY ON THE EXAMPLE Carrying out operations "3224 / m", "Prophets" AND FANATICS (1943-1957)

The article reveals the work of the Soviet authorities (NKGB-KGB) on the unification of the All-Ukrainian Union of Christians of the Pentecostal Evangelical Faith (UCPEF/KhEV) with the All-Union Council of Evangelical Baptist Christians (ACEBC/VSEKhB).The article also is devoted to the study of the role of the bodies of Soviet state security in carrying out of religious policy in Protestant environment in the territory of Soviet Ukraine on the example of their creation of a «legendary» religious center – All-Union Council of Evangelical Baptist Christians, as well as the apparatus of its republican and regional representatives (i.e. senior elders/presbyters). The article also highlights the plans of the Soviet state security agencies for the use of the leadership of ACEBC in the implementation of agent-operational measures to absorb other related to ACEBC protestant movements of the USSR (Pentecostals, Darbists, reformists etc.), to reduce their numbers, to subordinate influence to the organs of Soviet authorities and, ultimately, to lead to moral and physical decay. For the first time, the article publishes the name of undercover operations («FANATICS» and «PROPHETS»), which were carried out by the NKGB-KGB bodies in the protestant milieu of the Ukrainian SSR in 1943-1957, and also indicates, for the first time, the operational pseudonyms of secret agents of the NKGB-KGB, who were involved in these operations. For example M. Melnikov – agent “MIRGORODSKIY”, G. Ponurko – agent “GOROSHKO”, M. Boot – agent “LYSOV” and others, who operated in a Protestant religious environment with the decryption of their operational pseudonymsand also indicates the intelligence and operational activities that were carried out by the Soviet security organs in the Protestant environment, which were aimed at subordinating this environment to the influence of the Soviet special services.

A Multiorganizational Cooperation Framework for Neighborhood Disaster Resilience

Climate change and growth in coastal population make many American communities increasingly vulnerable to coastal disasters such as hurricanes, winter storms, and tsunamis. This research argues that neighborhood-level organizations can and should play a significant role in preparation for and response to such events. In particular, neighborhood and homeowner associations routinely play key roles in mobilizing community response to safety, physical decay, and infrastructure problems, all central concerns in preparation for and recovery from natural disaster. Neighborhood organizations then can act as lynchpin actors in a multiorganizational cooperation framework for disaster preparation, recovery, and resilience.

Português

According to IBGE, the age group of the population had a significant increase from 2012, where life expectancy in 1940 was 45.5, and in 2018 is 76.2 years in men and 79.8 years in women. The way that the elderly are seen and treated by society ends up giving a non-real image, because age began to be treated as a stage of life characterized by physical decay and absence of social roles from the second half of the nineteenth century. This research intends to contribute to the analysis of how the current society sees and treats the age, and trying to answer questions of if the prejudice exists, and what it represents to be old in the conception of these elderly. The methodology to be used is qualitative and quantitative. Based on the literature review, historical data, and the application of a small WHOQOL-bref questionnaire adapted for the elderly, to be answered by older people from 60 years old. Selected and qualitatively articulated bibliographies. This information will be analyzed to dialogue with the official documentation in the investigation, privileged to explain the social historical process of the elderly. The results show that seniors have autonomy, and have active social participation, and that age does not prevent them from accomplishing what they want efficiently.

Temporal Change in Radiological Environments on Land after the Fukushima Daiichi Nuclear Power Plant Accident

Massive environmental monitoring has been conducted continuously since the Fukushima Daiichi Nuclear Power accident in March of 2011 by different monitoring methods that have different features together with migration studies of radiocesium in diverse environments. These results have clarified the characteristics of radiological environments and their temporal change around the Fukushima site. At three months after the accident, multiple radionuclides including radiostrontium and plutonium were detected in many locations; and it was confirmed that radiocesium was most important from the viewpoint of long-term exposure. Radiation levels around the Fukushima site have decreased greatly over time. The decreasing trend was found to change variously according to local conditions. The air dose rates in environments related to human living have decreased faster than expected from radioactive decay by a factor of 2–3 on average; those in pure forest have decreased more closely to physical decay. The main causes of air dose rate reduction were judged to be radioactive decay, movement of radiocesium in vertical and horizontal directions, and decontamination. Land-use categories and human activities have significantly affected the reduction tendency. Difference in the air dose rate reduction trends can be explained qualitatively according to the knowledge obtained in radiocesium migration studies; whereas, the quantitative explanation for individual sites is an important future challenge. The ecological half-lives of air dose rates have been evaluated by several researchers, and a short-term half-life within 1 year was commonly observed in the studies. An empirical model for predicting air dose rate distribution was developed based on statistical analysis of an extensive car-borne survey dataset, which enabled the prediction with confidence intervals. Different types of contamination maps were integrated to better quantify the spatial data. The obtained data were used for extended studies such as for identifying the main reactor that caused the contamination of arbitrary regions and developing standard procedures for environmental measurement and sampling. Annual external exposure doses for residents who intended to return to their homes were estimated as within a few millisieverts. Different forms of environmental data and knowledge have been provided for wide spectrum of people. Diverse aspects of lessons learned from the Fukushima accident, including practical ones, must be passed on to future generations.

WEIGHT AS AN EXPRESSION OF HUMAN SPIRITUAL STATE (ON THE MATERIAL OF THE NEXT FALLING V. VINNYCHENKO)

The article deals with the reflection of human spiritual state through the body in Vladimir Vynnychenko’s later fiction – his novels "The Solar Machine", "The New Commandment", and "The Leper Colony". In their form, these texts are closer to political treatises being aimed at solving certain social problems. They postulate the explicit correlation between a person’s state of health and the level of his/her morality, "purity" of life, and predisposition to suicide. The research singles out the main indicators of destructive human nature, which have a bodily expression; the relationship between physical and spiritual degradation of the individual; the author's variant of solving the problem of spiritual and physical decay of mankind. It is postulated that in the writer’s fictional world physical degradation leads to a character’s gradual moral decay, reduction of one’s requirements for oneself and others, and rapid adaptation to the living conditions of a destructive society. This research, although revealing the ways somatic vocabulary is used in V. Vynnychenko’s later works, does not exhaust the issue. Further exploration may result in more in-depth studies of corporeality in his writings of different periods, as well as their comparison with the texts of other emigré writers (Vasyl Barka, Ivan Bagryany, and others).

Decaying infrastructures in the post-industrial city: An urban political ecology of the US pipeline crisis

Infrastructure is critical to the ways in which urban inequality is produced and experienced. Across US post-industrial contexts urban infrastructures are decaying, causing problems to the capacity of various systems to deliver essential resource flows for social reproduction. This paper examines the US pipeline crisis to understand why, how and with what effects infrastructure has undergone a process of physical decay, concentrated across inner-city areas. It uses a case study of Camden, New Jersey, a poor city in which infrastructure has undergone decades of neglect, privatisation and under-maintenance. This decay has created difficulties in sustaining a safe, universal and fully functioning infrastructure. To understand these dynamics, the paper advances an urban political ecology approach to examining these infrastructural geographies. It makes three key contributions. First, it considers how to conceptualise decay and its effect on the urban circulations that have been enabled/disabled by infrastructure through the notion of unbounding. Second, given the highly segregated infrastructural experiences between a black city and white suburbs, the paper draws on recent geographic scholarship on racial capitalism, emphasising the role of race in the governing of infrastructure and in accounting for Camden’s conditions of decay. Third, the paper advances a relational theorisation that draws on concepts emanating from urban political ecology and associated research on infrastructure in cities of the global South. With the reported, widespread decay of infrastructures in global North, post-industrial contexts, a relational theorisation can draw on long-established vocabularies that challenge where we locate the ‘infrastructural South’ and prompt new political urban questions.

ICRP Publication 141: Occupational Intakes of Radionuclides: Part 4.

The 2007 Recommendations (ICRP, 2007) introduced changes that affect the calculation of effective dose, and implied a revision of the dose coefficients for internal exposure, published previously in the Publication 30 series (ICRP, 1979a,b, 1980a, 1981, 1988) and Publication 68 (ICRP, 1994b). In addition, new data are now available that support an update of the radionuclide-specific information given in Publications 54 and 78 (ICRP, 1989a, 1997) for the design of monitoring programmes and retrospective assessment of occupational internal doses. Provision of new biokinetic models, dose coefficients, monitoring methods, and bioassay data was performed by Committee 2 and its task groups. A new series, the Occupational Intakes of Radionuclides (OIR) series, will replace the Publication 30 series and Publications 54, 68, and 78. OIR Part 1 (ICRP, 2015) describes the assessment of internal occupational exposure to radionuclides, biokinetic and dosimetric models, methods of individual and workplace monitoring, and general aspects of retrospective dose assessment. OIR Part 2 (ICRP, 2016), OIR Part 3 (ICRP, 2017), this current publication, and the final publication in the OIR series (OIR Part 5) provide data on individual elements and their radioisotopes, including information on chemical forms encountered in the workplace; a list of principal radioisotopes and their physical half-lives and decay modes; the parameter values of the reference biokinetic models; and data on monitoring techniques for the radioisotopes most commonly encountered in workplaces. Reviews of data on inhalation, ingestion, and systemic biokinetics are also provided for most of the elements. Dosimetric data provided in the printed publications of the OIR series include tables of committed effective dose per intake (Sv per Bq intake) for inhalation and ingestion, tables of committed effective dose per content (Sv per Bq measurement) for inhalation, and graphs of retention and excretion data per Bq intake for inhalation. These data are provided for all absorption types and for the most common isotope(s) of each element. The online electronic files that accompany the OIR series of publications contains a comprehensive set of committed effective and equivalent dose coefficients, committed effective dose per content functions, and reference bioassay functions. Data are provided for inhalation, ingestion, and direct input to blood. This fourth publication in the OIR series provides the above data for the following elements: lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), actinium (Ac), protactinium (Pa), neptunium (Np), plutonium (Pu), americium (Am), curium (Cm), berkelium (Bk), californium (Cf), einsteinium (Es), and fermium (Fm).

Reviving the House of Fiction: John Banville’s Birchwood

This paper examines the limits of postmodernist techniques and forms through a study of John Banville’s Birchwood (1973), a novel which can be said to overtly question the ‘tools’ a writer/artist has at his disposal to create meaning. Ostensibly about a family saga, the text is really an examination of how art can, and must, be sustained in the face of a dissolution of meaning embodied by the physical decay of Birchwood itself. Chronicling the passing of the era of the big house and yet choosing to remain within the crumbling remains is a clear indication of the artist’s commitment to creating fiction. Birchwood can be considered the first novel in Banville’s oeuvre in which such a position is clearly articulated. In the novel, Banville’s conscious subversion of modernist forms and devices, In addition to other tenets of Enlightenment thought and rationality, puts the limelight on the postmodern shift to ontological concerns and issues and is, as a consequence, a considered study of the act and possibility of writing in the face of such obstacles. The novel’s interrogation of the limits of metafiction and self-reflexivity, for example, and its acknowledgment of the constraints under which they are employed, paves a different way for an artist struggling to create coherence in the contemporary world.

Temporal changes of the ambient dose rate in the forest environments of Fukushima Prefecture following the Fukushima reactor accident

Approximately 70% of the total land area affected by the fallout from the Fukushima accident is forested, and therefore monitoring of the ambient dose rate in forest environments is essential to ensure that the population and natural habitats of these areas are protected from radiological hazards. However, there are little available data on the ambient dose rate for forest environments. This study investigated temporal changes in the ambient dose rate in different forest environments of Fukushima Prefecture. We conducted repeated measurements of the ambient dose rate in 2014 and 2016 at the same measurement points as those used by the Ministry of Agriculture, Fishery and Forestry of Japan (MAFF) in 2011. The measurements revealed that the decreasing trend in the ambient dose rate varied among the different forest types and time periods. The ambient dose rate in EGC decreased slower than that induced by the physical decay of radiocesium for the period of 2011–2014. However, such slow declining trend of ambient dose rate was likely followed by quick reduction during the following years (2014–2016 and 2011–2016). On the other hand, in MBL and DBF forests, the ambient dose rate decreased 10–20% faster than that induced solely by physical decay of radiocesium for the observation period 2011–2016.

Assessment of radioactive cesium deposition using ground-based gamma-ray spectrometry with a LaBr3(Ce) detector

Ground-based gamma-ray spectrometry using a LaBr3(Ce) detector was conducted to assess radioactive cesium deposition in soil contaminated by the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in Japan. Five sites, including a reference site with relatively low contamination, were selected as having different levels of ambient dose rate due to significant effects of radioactive fallout of 134Cs and 137Cs. According to ICRU Report 53, the radioactivity in the ground and dose rate at 1 m above the ground were determined from the measured net count rates of gamma-rays induced from radioactive cesium. Because the radioactivity and dose rate depended on the depth profile of radioactive cesium in the ground, a database of possible radioactivity and dose rate could be established according to several depth distributions. A new approach to estimate the depth profile was then developed by directly calculating dose rates of 134Cs and 137Cs at the same geometry through dose rate spectroscopy and comparing them with the database of possible dose rates of radioactive cesium. Once the depth profile was determined, radioactivity was estimated from the database depending on the depth profile in the ground. The activity ratio between two radioactive cesium was shown to average about 0.112, in December 2017. It was in good agreement with the originally same released amount of 134Cs and 137Cs at the time of the FDNPP accident, when physical decay correction was applied to the results of the radioactivity assessment.

Impact of decontamination on individual radiation doses from external exposure among residents of Minamisoma City after the 2011 Fukushima Daiichi nuclear power plant incident in Japan: a retrospective observational study

Following the Fukushima incident, radiation doses from external exposure accounted for the majority of the total doses. Although countermeasures are being implemented, with the aim of reducing radiation exposure, little information is available on the effects of decontamination on individual doses among the residents of radioactively contaminated areas. To evaluate the effectiveness of the decontamination measures in reducing individual doses, and to examine the influence of the timing of decontamination and the district, data were analysed for 18 392 adults and 3 650 children in Minamisoma City, Fukushima, who participated in a voluntary screening programme using individual radiation dosimeters (Glass Badge) between June 2013 and September 2016. The dose reduction rates (DRR) were calculated for one year by comparing the first and last three-month measurement results between areas with and without decontamination. Using a regression approach and Monte Carlo simulation, the dose reduction rate by decontamination eliminating the effect of physical decay (DRRd′) was also estimated as a function of the timing of the decontamination and the dose at the time of starting the decontamination. The annual DRR in areas with decontamination for both adults and children were significantly higher than those in areas without decontamination, depending on the timing of decontamination: 31%–36% for 2013–14 for adults in decontamination areas and 33%–35% for children in decontamination areas, compared to 12%–23% and 13%–23% for adults and children in areas without decontamination, respectively. There was a positive correlation between DRRd′ and individual doses, and DRRd′ was estimated at 30%–40% for adults and children with doses of 3 mSv y−1 in 2013 and 2014. This study demonstrated that decontamination does lower individual doses from external exposure. The higher the dose at the time of starting the decontamination, the greater the dose reduction rate by decontamination, regardless of the timing of the decontamination. Our study confirms that decontamination was useful for high-dose areas in the later phases of the incident.

Benzo[a]pyrene and 2,3-benzofuran induce divergent temporal patterns of AhR-regulated responses in zebrafish embryos (Danio rerio)

Biotests like the fish embryo toxicity test have become increasingly popular in risk assessment and evaluation of chemicals found in the environment. The large range of possible endpoints is a big advantage when researching on the mode of action of a certain substance. Here, we utilized the frequently used model organism zebrafish (Danio rerio) to examine regulative mechanisms in the pathway of the aryl-hydrocarbon receptor (AHR) in early development. We exposed embryos to representatives of two chemical classes known to elicit dioxin-like activity: benzo[a]pyrene for polycyclic aromatic hydrocarbons (PAHs) and 2,3-benzofuran for polar O-substituted heterocycles as a member of heterocyclic compounds in general (N-, S-, O-heterocycles; NSO-hets). We measured gene transcription of the induced P450 cytochromes (cyp1), their formation of protein and biotransformation activity throughout the whole embryonic development until 5 days after fertilization. The results show a very specific time course of transcription depending on the chemical properties (e.g. halogenation, planarity, Kow), the physical decay and the biodegradability of the tested compound. However, although this temporal pattern was not precisely transferable onto the protein level, significant regulation in enzymatic activity over time could be detected. We conclude, that a careful choice of time and end point as well as consideration of the chemical properties of a substance are fairly important when planning, conducting and especially evaluating biotests.

Texture: Faking the physical

Contemporary illustration is infatuated with texture. The imperfections of analogue processes and signs of physical decay, which were once incidental, or even irritating, are now highly sought after and frequently replicated in order to provide an ornamental layer to contemporary digital illustration. Nicholas Stevenson is an illustrator who uses texture this way. His visual language centres around analogue textures that are digitally applied from an ever-growing library of scanned surfaces: taken from worn book jackets, watermarked paper and ink smudges. This visual essay explores this topic through Nicholas's illustrations in dialogue with Gabrielle's written, critical commentary. Drawing on Mark Fisher's ideas about hauntology in twenty-first-century western culture, and Jean Baudrillard's simulacra, we intend to explore the latent effects of the ornamental application of analogue texture in digital illustration, with Nicholas Stevenson's work taking the role of both example and co-contributor.

Current state and trends in the content of 137Cs and 90Sr in abiotic and biotic components of Arctic ecosystems (Barents and Kara Seas case study)

This publication summarizes long-term data on radioactive contaminants in seawater, bottom sediments, and marine fish and describes current patterns in radionuclide distribution using data collected by the Murmansk Marine Biological Institute during cruises to the Barents and Kara Seas in 2015–2017. During the study period, no short-lived artificial radionuclides were found in the Barents and Kara Seas. 137Cs and 90Sr isotopes with a longer half-life are still registered in Atlantic waters that are the main source of radioactive contamination in these Arctic seas. Volumetric activity of 137Cs and 90Sr was compared at different depths. A uniform distribution of 137Cs in the vertical column of water and a tendency to increase the volume activity of 90Sr from surface to bottom were observed in the Barents Sea. Bottom sediments in the Kara Sea contain on average 2 times more 137Cs than the Barents Sea. Atlantic cod is characterized by an extremely low concentration of 137Cs in muscular tissue, about an order of magnitude lower than in the period of maximum contamination of Barents Sea waters observed in 1982. Currently there is a decreasing trend in concentrations of anthropogenic radioisotopes in the environment and biota. Processes of 137Cs and 90Sr removing from biotic and abiotic components are described with exponential functions. Due to natural marine purification processes, the decrease of 137Cs and 90Sr concentrations in the Barents and Kara Seas occur 2–4 times faster than the physical radioactive decay of these radionuclides.

Natural Hazards, Human Factors, and “Ghost Towns”: a Multi-Level Approach

The abandonment of inhabited places is a phenomenon that concerns many countries worldwide and Italy particularly where a large number of deserted settlements are hosted. Many are the factors driving and conditioning the abandonment of a site, such as natural extreme events (e.g. earthquakes, landslides, and floods) and/or human (not) actions. Once the site is abandoned, the built-up area experiences a progressive physical decay so posing problems about the policies to be adopted to manage and maintain the buildings (or their ruins). That being stated, the article proposes an integrated methodological approach to analyse both the natural/human factors causing the abandonment of settlements and conservation state of deserted places over time. To test the methodology, we considered the old town of Craco (Basilicata, Southern Italy) as a case study. That “ghost town”, whose fascinating urban and natural landscapes have been the set of numerous international films, was gradually transferred to other two places since the 1960s due to the landslides that have affected the site over the centuries. Three were the explicit key aims of the research. The first was to scrutinise the activations/reactivations of the landslides jointly with their effects on the built environment so to critical go over the actions put into the field by the institutions to mitigate the hydrogeological risk. The second was to examine whether and how the landslide occurrences conditioned the urban growth of the Craco over time. The third was to investigate in relation to the vegetation growth in the Craco downtown over the last 15 years or so, to infer clues on future decay trends and conservation strategies of the built environment. The purposes were reached considering a geological-geomorphological, historical, and remote-sensing approach. In detail, the first goal was met (re)considering a cross-correlated analysis, in diachronic key, of edited/unedited archive sources with geological/geomorphological perspectives. The second was followed up performing the analysis of the Craco urban growth over the centuries and correlating it with the history of landslide occurrences. The third target was pursued by means of NDVI (Normalized Difference Vegetation Index) time series obtained from Landsat TM and Sentinel 2 data along with HSV (Hue, Saturation, Value) colour system techniques applied to multi-date Google Earth photos. From the perspective angle, the results of this research can contribute to setup proper resilience strategies for sites subject to hydrogeological hazard similar to that affects Craco, thus helping to identify conservation plans as well as enhancement policies of “ghost towns”.

Soil properties and combustion temperature: Controls on the decomposition rate of pyrogenic organic matter

Pyrogenic carbon (PyC) is the material left behind after incomplete combustion of biomass, including a spectrum of materials ranging from charcoal to lightly charred biomass. We investigated the roles of combustion temperature and properties of soil at two distinct landform positions on carbon dioxide (CO2) flux from soil and decomposition of PyC. Bark from Pinus jeffreyi was charred at three temperatures (200 °C, 350 °C, and 500 °C) for an hour to create PyC before it was incubated with soil collected from eroding and depositional landform positions along the same hillslope. We determined the fraction of PyC in soil C at the beginning and end of the incubation using the Kurth-MacKenzie-Deluca digestion method. We found rates of microbial respiration in soil from the depositional landform position were over three times higher than from soil from the eroding landform position. The soil from the eroding landform position had less optimal decomposition conditions, including water holding capacity and organic matter content, compared with the soil from the depositional landform position. Furthermore, over the length of the incubation experiment, PyC concentrations decreased only in depositional soils that contained lower temperature chars, indicating that low temperature PyC has shorter residence times in soils from depositional landform positions, compared to eroding ones. Using scanning electron microscopy, we also observed physical decay of the low temperature chars. Previous research has shown that PyC is preferentially eroded from hillslopes post-fire. Here we show that erosion of PyC and deposition into depositional landform positions can cause the decay rate of PyC to significantly increase, exerting a significant control on the long-term fate of PyC in the soil system.

Critical Approaches to Ageing Body Politics in the Works of Erica Jong

The ways we read our bodies and bodily transformations are deeply inscribed in cultural meanings that vary across different historical times and societies. Even if the desire to achieve culturally imposed beauty standards and ideals is relevant to all age groups, anxieties about bodily decline become more pronounced as we approach the final stages of our lives. Physical changes are never just manifestations of cellular and organic loss, but can also be a source of troubled identifies and fragmented personalities caused by the mismatch between our external appearance and the inner perception of the self. This paper offers the longitudinal analysis of female processes of ageing from age-studies and feminist perspectives, as depicted in the works of Erica Jong, a contemporary American writer. It uncovers significant aspects of the pressures older women are subjected to in order to look more appealing in youth-oriented cultures, and demonstrates that the human body is often regarded as a conflicting site of perpetual ambiguities and troubled feelings caused by physical decay.

CHANGES OF ABSORBED DOSE RATE IN AIR BY CAR-BORNE SURVEY IN NAMIE TOWN, FUKUSHIMA PREFECTURE AFTER THE FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT.

The latest car-borne survey was carried out by Hirosaki University in order to grasp the local distribution of the absorbed dose rate in air after the evacuation order was lifted on Namie Town in 2017. The car-borne survey of absorbed dose rate in air was carried out on most of the roads which were accessible by car in Namie Town using a 3-in × 3-in NaI(Tl) scintillation spectrometer. The range of the absorbed dose rate in air was calculated to be 0.041-11 μGy h-1. The distribution maps of the absorbed dose rate in air were drawn based on the data obtained during the surveys in 2011, 2015 and 2017. The comparison of these absorbed dose rates in air suggests that the elevated absorbed dose rate in air in Namie Town caused by the FDNPP accident may be decreasing faster than natural decline which includes weathering effect and physical decay due to the artificial decontamination.

Dissolution behaviour of radiocaesium-bearing microparticles released from the Fukushima nuclear plant

Radiocaesium-bearing microparticles (CsMPs) composed of silicate glass were released by the Fukushima Daiichi Nuclear Power Plant accident in March 2011. Since CsMPs contain a high concentration of radiocaesium, their dynamics and fate in the environment are urgent issues to be investigated. Here, we show that CsMPs are dissolved by weathering in the environment and that their radioactivity is more rapidly decreased by dissolution than the physical decay of radiocaesium. We conducted dissolution experiments with CsMPs in pure water that absorbed CO2 from the atmosphere and in artificial seawater at several temperatures. The dissolution progress was monitored by the decrease in the 137Cs radioactivity in CsMPs, and the dissolution rate was estimated. The activation energy for the dissolution of CsMPs was estimated to be 65 and 88 kJ/mol and the dissolution rate at 13 °C (approximate annual mean temperature in Fukushima City) was 0.014 and 0.140 μm/y for pure water and seawater, respectively, assuming that radiocaesium is uniformly distributed in spherical CsMPs. The shapes of the CsMPs dissolved in pure water were considerably altered, suggesting that the dissolution proceeded without maintaining the geometry. Tin oxide and iron oxide nanoparticulates formed on the surfaces. Such features were similar to those observed in CsMPs recently collected in Fukushima Prefecture, indicating that weathering dissolution of CsMPs is also occurring in the environment. For the CsMPs dissolved in seawater, a crust of secondary Mg- and Fe-rich minerals was formed, and the glass matrix inside the crust decreased, creating space between the crust and the glass matrix.