Miracle-dz/UniFAR-FTUs huggingface dataset:
Uranium uptake onto Magnox sludge minerals studied using EXAFS

Abstract Around the world large quantities of sludge wastes derived from nuclear energy production are currently kept in storage facilities. In the UK, the British government has marked sludge removal as a top priority as these facilities are nearing the end of their operational lifetimes. Therefore chemical understanding of uranium uptake in Mg-rich sludge is critical for successful remediation strategies. Previous studies have explored uranium uptake by the calcium carbonate minerals, calcite and aragonite, under conditions applicable to both natural and anthropogenically perturbed systems. However, studies of the uptake by Mg-rich minerals such as brucite [Mg(OH)2], nesquehonite [MgCO3·3H2O] and hydromagnesite [Mg5(CO3)4(OH)2·4H2O], have not been previously conducted. Such experiments will improve our understanding of the mobility of uranium and other actinides in natural lithologies as well as provide key information applicable to nuclear waste repository strategies involving Mg-rich phases. Experiments with mineral powders were used to determine the partition coefficients (Kd) and coordination of UO22+ during adsorption and co-precipitation with brucite, nesquehonite and hydromagnesite. The Kd values for the selected Mg-rich minerals were comparable or greater than those published for calcium carbonates. Extended X-ray absorption fine structure analysis results showed that the structure of the uranyl-triscarbonato [UO2(CO3)3] species was maintained after surface attachment and that uptake of uranyl ions took place mainly via mineral surface reactions.
High to ultrahigh temperature contact metamorphism and dry partial melting of the Tasiuyak paragneiss, Northern Labrador

Contact aureoles of the anorthositic to granitic plutons of the Mesoproterozoic Nain Plutonic Suite (NPS), Labrador, are particularly well developed in the Palaeoproterozoic granulite facies, metasedimentary, Tasiuyak gneiss. Granulite facies regional metamorphism (MR), c. 1860 Ma, led to biotite dehydration melting of the paragneiss and melt migration, leaving behind biotite‐poor, garnet–sillimanite‐bearing quartzofeldspathic rocks. Subsequently, Tasiuyak gneiss within a c. 1320 Ma contact aureole of the NPS was statically subjected to lower pressure, but higher temperature conditions (MC), leading to a second partial melting event, and the generation of complex mineral assemblages and microstructures, which were controlled to a large extent by the textures of the MR assemblage. This control is clearly seen in scanning electron microscopic images of thin sections and is further supported by phase equilibria modelling. Samples collected within the contact aureole near Anaktalik Brook, west of Nain, Labrador, mainly consist of spinel–cordierite and orthopyroxene–cordierite (or plagioclase) pseudomorphs after MR sillimanite and garnet, respectively, within a quartzofeldspathic matrix. In addition, some samples contain fine‐grained intergrowths of K‐feldspar–quartz–cordierite–orthopyroxene inferred to be pseudomorphs after osumulite. Microstructural evidence of the former melt includes (i) coarse‐grained K‐feldspar–quartz–cordierite–orthopyroxene domains that locally cut the rock fabric and are inferred to represent neosome; (ii) very fine‐ to medium‐grained cordierite–quartz intergrowths interpreted to have formed by a reaction involving dissolution of biotite and feldspar in melt; and (iii) fine‐scale interstitial pools or micro‐cracks filled by feldspar interpreted to have crystallized from melt. Ultrahigh temperature (UHT) conditions during contact metamorphism are supported by (i) solidus temperatures >900 °C estimated for all samples, coupled with extensive textural evidence for contact‐related partial melting; (ii) the inferred (former) presence of osumilite; and (iii) titanium‐in‐quartz thermometry indicating temperatures within error of 900 °C. The UHT environment in which these unusual textures and minerals were developed was likely a consequence of the superposition of more than one contact metamorphic event upon the already relatively anhydrous Tasiuyak gneiss.
Evaluation of multireanalysis products with in situ observations over the Tibetan Plateau

[1] As the highest plateau in the world, the Tibetan Plateau (TP) strongly affects regional weather and climate as well as global atmospheric circulations. Here six reanalysis products (i.e., MERRA, NCEP/NCAR-1, CFSR, ERA-40, ERA-Interim, and GLDAS) are evaluated using in situ measurements at 63 weather stations over the TP from the Chinese Meteorological Administration (CMA) for 1992–2001 and at nine stations from field campaigns (CAMP/Tibet) for 2002–2004. The measurement variables include daily and monthly precipitation and air temperature at all CMA and CAMP/Tibet stations as well as radiation (downward and upward shortwave and longwave), wind speed, humidity, and surface pressure at CAMP stations. Four statistical quantities (correlation coefficient, ratio of standard deviations, standard deviation of differences, and bias) are computed, and a ranking approach is also utilized to quantify the relative performance of reanalyses with respect to each variable and each statistical quantity. Compared with measurements at the 63 CMA stations, ERA-Interim has the best overall performance in both daily and monthly air temperatures, while MERRA has a high correlation with observations. GLDAS has the best overall performance in both daily and monthly precipitation because it is primarily based on the merged precipitation product from surface measurements and satellite remote sensing, while ERA-40 and MERRA have the highest correlation coefficients for daily and monthly precipitation, respectively. Compared with measurements at the nine CAMP stations, CFSR shows the best overall performance, followed by GLDAS, although the best ranking scores are different for different variables. It is also found that NCEP/NCAR-1 reanalysis shows the worst overall performance compared with both CMA and CAMP data. Since no reanalysis product is superior to others in all variables at both daily and monthly time scales, various reanalysis products should be combined for the study of weather and climate over the TP.
Towards Single Point Incremental Forming Accuracy: An Approach for the Springback Effect Compensation

The springback effect is a common occurrence in incremental forming, where the formed workpiece elastically deforms and slightly shifts from the desired shape after the tool is released. This phenomenon causes an error between the target and obtained shape, leading to reduced geometric accuracy. It is is a significant challenge in incremental forming and it is a reason why the process has lower accuracy compared to conventional forming methods. This paper presents an off-line springback effect compensation model aiming to generate an optimized toolpath that accounts for the material springback effect. The model is based on an off-line numerical simulation conducted on Abaqus/CAE software. The results demonstrated that the proposed model can effectively reduce the error between the desired and obtained shape by 31.8% for aluminum, 63.2% for copper, and 63.1 % for magnesium.
Assessing regional land‐use/cover influences on New Jersey Pinelands streamflow through hydrograph analysis

Relative baseflow volume and streamflow flashiness indices were used to assess relationships between land use/cover and streamflow regime in nine New Jersey (NJ) Pinelands streams. Baseflow index (BFI) and Richards–Baker flashiness index (RBI) were estimated on an October–September water year, with period‐of‐record changes assessed by trend analysis and differences between watersheds assessed by examining index versus land‐use/cover relationships using a data period common to all study sites. Four streams, among the more urbanized watersheds of the nine study sites, were found to have significant (α = 0·05) trends in both indices. The two most urbanized study sites showed decreasing baseflow and increasing flashiness; however, the other two streams showed the opposite trends. An apparent slowdown in urbanization towards the second half of the streamflow period of record, along with potential changes in wetland agricultural practices in the latter two watersheds, may explain their trend results. A marginally significant (α = 0·10) decreasing relationship was found between mean annual BFI and wetland agriculture, whereas a significant (α = 0·05) increasing relationship was determined between mean annual RBI and artificial lakes/reservoirs. Principal component analysis showed an association between wetland agriculture and artificial lakes/reservoirs which suggested that both of the significant index versus land‐use/cover relationships reflect wetland agricultural activities. Because these significant relationships involved land uses/covers with small spatial extents (⩽5%), they demonstrated that land‐use practices can have a greater impact than spatial extent on stream hydrology. This study is the first step in assessing the effect on the NJ Pinelands stream ecology by streamflow alteration due to wetland agricultural activities. Copyright © 2006 John Wiley & Sons, Ltd.
Application of Connection Layer on Equivalent Model of GIS Basin Insulator

Aiming at the problem that the existing finite element model can not accurately characterize the dynamic characteristics of basin insulator in GIS, a basin insulator in GIS model establishment method based on connection layer model was proposed. The connection layer model was established at the bolt joint of GIS basin insulator outer flange and insulator. Based on the modal experimental data, the parameters of the connection layer model were identified by genetic algorithm. Compared with the existing model establishment methods, the errors of the corresponding natural frequency are reduced from the minimum 7% to less than 2%, which proves the accuracy of finite element calculation of the GIS basin insulator after parameter identification.
Thermogenic gas hydrates in the northern Cascadia margin

Gas hydrates are ice-like solids that form in rigid cage structures under specific conditions of pressure, temperature, and gas and water concentration. Marine gas hydrates are stable in pore spaces of sediments in water depths greater than ∼300 m beneath the slopes of active and passive continental margins [Kvenvolden, 1988]. The lower limit of hydrate occurrence in marine sediments is determined by the geothermal gradient, so that the zone of hydrate stability is generally contained within the first few hundred meters of sediment. Continental hydrates occur in polar permafrost regions in the Arctic and Siberia. Most of the hydrates that have been discovered contain methane derived from microbial processes. Other hydrocarbons can also form hydrates, but in different structures of the surrounding water cages. Structure I, the most prevalent form, contains mostly (>99%) microbial methane, a small amount of ethane, and traces of C2+ hydrocarbons [Sassen et al, 2001]. Structure II and structure H hydrates contain significant quantities of thermogenic methane and larger, more complex hydrocarbons formed at high temperatures from fossil organic matter (i.e.,kerogen) or oil [Sassen and MacDonald, 1994]. The gas origin is inferred from measurements of the carbon-13 isotopic ratio (δ13); microbial methane is depleted in 13C (δ13 <−60‰) relative to thermogenic methane (δ13 from −20‰ to −50‰).
Comparison of Single‐ and Double‐Ring Infiltrometer Methods on Stony Soils

Infiltration measurements to determine the field saturated hydraulic conductivity (Kfs) in arid lands are often plagued by large variations that can be attributed to soil heterogeneity, the measurement method, the number of replications, and the Kfs calculation method used. This study addressed the question of how comparable are two different measurement methods, the single‐ring infiltrometer (SR) and double‐ring infiltrometer (DR), when applied at three locations in a semiarid part of Chile that show moderate (15%) to high (55%) stoniness. Additionally, Kfs variations due to different calculation methods for the same measurement method were thoroughly investigated, considering nine methods for the SR and 10 methods for the DR. Results showed that different calculation techniques gave sometimes significantly different estimates of Kfs when using the same data set, and those relative differences were conserved between measurement locations. When comparing the same calculation technique for both SR and DR, both methods gave equivalent Kfs estimates for each location. The SR infiltration measurements were modeled better using a transient approach, while infiltration models considering steady state performed better with the DR.
Use of a reactive gas transport model to determine rates of hydrocarbon biodegradation in unsaturated porous media

A mathematical model is presented that simulates the transport and reaction of any number of gaseous phase constituents (e.g. CO{sub 2}, O{sub 2}, N{sub 2}, and hydrocarbons) in unsaturated porous media. The model was developed as part of a method to determine rates of hydrocarbon biodegradation associated with natural cleansing at petroleum product spill sites. The one-dimensional model can be applied to analyze data from column experiments or from field sites where gas transport in the unsaturated zone is approximately vertical. A coupled, non-Fickian constitutive relation between fluxes and concentration gradients, together with the capability of incorporating heterogeneity with respect to model parameters, results in model applicability over a wide range of experimental and field conditions. When applied in a calibration mode, the model allows for the determination of constituent production/consumption rates as a function of the spatial coordinate. Alternatively, the model can be applied in a predictive mode to obtain the distribution of constituent concentrations and fluxes on the the basis of assumed values of model parameters and a biodegradation hypothesis. Data requirements for the model are illustrated by analyzing data from a column experiment designed to determine the aerobic degradation rate of toluene in sediments collected from amore » gasoline spill site in Galloway Township, New Jersey. 15 refs., 4 figs., 4 tabs. « less
Rock moisture data from the juneau icefield (alaska) and its significance for mechanical weathering studies

Information was obtained regarding rock moisture content from nunataks along a west to east transect across the Juneau Icefield in Alaska. The data, together with rock temperatures and general climatic information, were collected for east-, west-, north- and south-facing samples. For one day data were collected every hour. The resulting information indicates the spatial and temporal variability that can exist over both short distances and short time-spans. It is suggested that this variability can have important repercussions with respect to weathering processes. The number of wetting and drying cycles monitored greatly depends upon the level of sample saturation that is considered significant. Available information suggests that wetting and drying can be operating at more than one level within the rock and that this will result in different weathering products. Wetting and drying may be more important than has been previously thought, both in terms of a weathering agent in its own right and as one that interacts with other processes, thereby speeding up their effect upon the rock. Des informations ont ete recueillies concernant le contenu en eau des nunataks selon un transect ouest-est au travers de l'Icefield Juneau en Alaska. Les donnees concernant l'humidite ont ete notees en meme temps que des observations concernant les temperatures des roches et les composantes climatiques, et cela pour des echantillons recoltes en des lieux exposes a l'est, a l'ouest, au nord et au sud. L'information rassemblee indique une grande variabilite spatiale et temporelle des observations aussi bien sur des distances courtes que sur des periods de temps reduites. Il est suggere que cette variabilite peut avoir des repercussions importantes en ce qui concerne les processus d'alteration. Le nombre de cycles de sechage et d'humidification observe depend pour beaucoup du degre de saturation des echantillons qui est, de ce fait, un facteur considere comme significatif. L'information disponible suggere que l'humidification et le sechage peuvent se produire a plus d'un niveau dans la roche et que cela determine des productions differentes de debris. Ces processus d'humidification et de sechage peuvent etre plus importants que ce qui a ete suppose precedemment, aussi bien comme agent d'alteration simple que comme processus se combinant avec d'autres.
A Hf-isotope perspective on continent formation in the south Peruvian Andes

Abstract Convergent continental margins are the primary host of both growth and loss of continental crust. Continental growth largely occurs via subduction-driven magmatism, whereas continental loss largely occurs via subduction erosion and sediment subduction. Because the latter typically involves partial recycling into magmas, both growth and loss of continental crust can be represented in the magmatic record. The degree of crustal recycling can be estimated from the initial Hf isotope signatures in both magmatic and detrital zircon grains. Recent insights into the geodynamic evolution of the Peruvian margin, in combination with a new dataset of Hf isotopic data on zircon from the Carboniferous to Early Cretaceous, enable us to (1) compare the geodynamic history of the southern Peruvian margin with its Hf isotopic evolution, and (2) quantify the crustal growth between 500 and 135 Ma. The data exhibit a correlation with trends in isotope composition v. time and reflect the dominantly extensional regime that prevailed from the onset of subduction from 530 Ma to c. 135 Ma. This study demonstrates that the Peruvian margin experienced continental growth with juvenile input to arc magmatism of 30–45% on average, and illustrates the use of U–Pb and Hf isotopes in zircon as a tool to trace episodes of crustal growth through time. Supplementary material: Hf istopic analyses on zircon (A1 and A2) and new U–Pb zircon ages (A3) are available at http://www.geolsoc. org.uk/SUP18661.
The unity and diversity of verbal and visuospatial creativity: Dynamic changes in hemispheric lateralisation

The investigation of similarities and differences in the mechanisms of verbal and visuospatial creative thinking has long been a controversial topic. Prior studies found that visuospatial creativity was primarily supported by the right hemisphere, whereas verbal creativity relied on the interaction between both hemispheres. However, creative thinking also involves abundant dynamic features that may have been ignored in the previous static view. Recently, a new method has been developed that measures hemispheric laterality from a dynamic perspective, providing new insight into the exploration of creative thinking. In the present study, dynamic lateralisation index was calculated with resting‐state fMRI data. We combined the dynamic lateralisation index with sparse canonical correlation analysis to examine similarities and differences in the mechanisms of verbal and visuospatial creativity. Our results showed that the laterality reversal of the default mode network, fronto‐parietal network, cingulo‐opercular network and visual network contributed significantly to both verbal and visuospatial creativity and consequently could be considered the common neural mechanisms shared by these creative modes. In addition, we found that verbal creativity relied more on the language network, while visuospatial creativity relied more on the somatomotor network, which can be considered a difference in their mechanism. Collectively, these findings indicated that verbal and visuospatial creativity may have similar mechanisms to support the basic creative thinking process and different mechanisms to adapt to the specific task conditions. These findings may have significant implications for our understanding of the neural mechanisms of different types of creative thinking.
Underplating process from melange formation to duplexing: Example from the Cretaceous Shimanto Belt, Kii Peninsula, southwest Japan

Accretionary complexes are considered to form through off scraping and underplating, which results in the lateral and vertical growth of an accretionary prism. Accretion of the upper part of the oceanic crust and the formation of melange are important components of the accretionary process, although the origin of melange is considered controversial. In order to better understand the origin of melange and its role in accretion, in particular during underplating, we have studied the relationship between the formation of melange and duplexing in the Miyama Assemblage. Here the melange is composed dominantly of shale, basalt, chert, and sandstone. This study stresses the following features: (1) the structure of the Miyama Assemblage appears to be a composite suite of landward and seaward dipping duplexes; (2) the melange fabric displays a systematic asymmetry, which may have resulted through shearing along the decollement; and (3) facing of horses within duplexes changes from north to south, coinciding with a change in the sense of shear inferred from the melange fabric, which suggests that it formed prior to duplexing.
Assessing the impact of neutron relative biological effectiveness on all solid cancer mortality risks in the Japanese atomic bomb survivors

Abstract Purpose Risk analyses, based on relative biological effectiveness (RBE) estimates for neutrons relative to gammas, were performed; and the change in the curvature of the risk to dose response with increasing neutron RBE was analyzed using all solid cancer mortality data from the Radiation Effect Research Foundation (RERF). Results were compared to those based on incidence data. Materials and methods This analysis is based on RERF mortality data with separate neutron and gamma doses for colon doses, from which organ averaged doses could be calculated. A model for risk ratio variation with RBE was developed. Results The best estimate of the neutron RBE considering mortality data was 200 (95% confidence interval (CI): 50–1010) for colon dose using the weighted-dose approach and for organ averaged dose 110 (95% CI: 30–350). The ERR risk ratios for all solid cancers combined, for the best fitting neutron RBE estimate and the neutron RBE of 10 result in a ratio of 0.54 (95% CI: 0.17–0.85) for colon dose and 0.55 (95% CI: 0.18–0.87) for organ averaged dose. The risk to dose response curvature became significantly negative (concave down) with increasing RBE, at a neutron RBE of 170 using colon dose and at an RBE of 90 using organ averaged dose for males when fitting a linear-quadratic dose response. For females, the curvature decreased toward linearity with increasing neutron RBE and remained significantly positive until RBE of 80 and 40 using colon and organ averaged dose, respectively. For higher neutron RBEs, no significant conclusion could be drawn about the shape of the dose–response curve. Conclusions Application of neutron RBE values higher than 10 results in substantially reduced cancer mortality risk estimates and a significant reduction in curvature of the risk to dose responses for males. Using mortality data, the best fitting neutron RBE is much higher than when incidence data is used. The neutron RBE ranges covered by the overlap in the CIs from both the mortality and incidence analyses are 50–190 using colon dose and in all cases, the best fitting neutron RBE and lower 95% CI are higher than the value of 10 traditionally applied by the RERF. Therefore, it is recommended to consider uncertainties in neutron RBE values when calculating radiation risks and discussing the shape of dose responses using Japanese A-bomb survivors data.