Top PDF Continuing <sup>137</sup>Cs release to the sea from the Fukushima Dai-ichi Nuclear Power Plant through 2012

Continuing <sup>137</sup>Cs release to the sea from the Fukushima Dai-ichi Nuclear Power Plant through 2012

Continuing <sup>137</sup>Cs release to the sea from the Fukushima Dai-ichi Nuclear Power Plant through 2012

itoring from 3 April at ULD clearly showed that 137 Cs radioactivity increased sharply until 6 April and then started decreasing exponentially (Fig. 2b). This drastic change on 6 April should reflect a sudden decrease of 137 Cs input to the main harbour, and the only documented event that could be related is the TEPCO’s operation that stopped the leak in front of unit 2 in the early morning of 6 April (Government of Japan, 2011).

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Radioactivity release from the Fukushima accident and its consequences: A review

Radioactivity release from the Fukushima accident and its consequences: A review

Recently, computer simulations revealed that on average only 8% of the 137 Cs airborne particles are expected to deposit within an area of 50 km around the accident site and about 50% of the airborne particles would be deposited outside a radius of 1000 km. Furthermore, about 25% would spread even further beyond 2000 km (Lelieveld et al., 2012). This study clearly indicates that, as was observed in the Chernobyl accident, reactor accidents are likely to cause radioactive contamination well beyond the national bor- ders. Therefore, depending on the degree of contamination, this could lead to very difficult international and diplomatic conflicts between the nation where a severe accident occurs and neigh- boring countries that would be affected by the accident. As for the Fukushima accident, because of the geographic location of the nuclear power plant e at the beach of the Pacific Ocean e and Fukushima’s meteorological conditions, including wind direction that mostly flows towards the Pacific Ocean, more than 80% of the radioactivity released from the crippled reactors flowed into the sea (Hoeve and Jacobson, 2012; Christoudias and Lelieveld, 2013). So fortunately only about 20% of the released radioactivity from the Fukushima accident (0.8% of the core inventory as shown in Fig. 1) was deposited over the Japanese land, keeping the exposed popu- lation relatively low.
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<sup>137</sup>Cs off Fukushima Dai-ichi, Japan &ndash; model based estimates of dilution and fate

<sup>137</sup>Cs off Fukushima Dai-ichi, Japan &ndash; model based estimates of dilution and fate

north, i.e. upstream of the nuclear power plant, whereas activities assigned by the “Point Kriging” applied by Bailly du Bois et al. (2012) assigns activities upstream, which rank among the highest in the whole region (their Fig. 4a). This biases their early inventories high. Sec- ond, their late (i.e. mid April till July) inventories are, on the other hand, biased low because of the detec- tion limit inherent to the respective 137 Cs measurements (10 to 50 Bq l −1 , Buesseler et al., 2011). The detection limit may well transfer to a substantial inventory un- derestimation of 1 to 7 p Bq (in the 60 × 120 km box assuming a surface mixed layer depth of 20 m) but is not accounted for in the analysis. We conclude that the combined effect of “early” inventories biased high and “late” inventories biased low is an overestimation of the slope of the logarithmic fit that, by extrapolation back- wards in time, biases the discharge estimate of Bailly du Bois et al. (2012) high. Third, their extrapolation back- wards in time implicitly assumes a constant transport of
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<sup>90</sup>Sr and <sup>89</sup>Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

<sup>90</sup>Sr and <sup>89</sup>Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

centrations in surface water adjacent to Fukushima have been well documented, releases of radiostrontium into the sea are poorly investigated (Povinec et al., 2012). The main rea- son for this lack of data resides in the difficulties of pre- concentrating and analyzing 90 Sr in seawater. The recent study by Povinec et al. (2012) was the first report assessing the impact of radiostrontium released from the Fukushima Dai-ichi nuclear power plant into the marine environment. Their data on 90 Sr in coastal seawater (near the discharging channel in Fukushima Dai-ichi NPP) were obtained from the Ministry of Education, Culture, Sports, Science and Tech- nology (MEXT). Concentrations of 90 Sr reached up to four orders of magnitude greater than the pre-Fukushima levels (1.2 Bq m − 3 ). Between March and November 2011, maxima
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S<sup>4</sup>CAST v2.0: sea surface temperature based statistical seasonal forecast model

S<sup>4</sup>CAST v2.0: sea surface temperature based statistical seasonal forecast model

the tropical Atlantic SST as a dominant factor in the WAM variability at interannual and seasonal timescales (Janowiak, 1988; Janicot, 1992; Fontaine and Janicot, 1996). Losada et al. (2010b) found how the response to an isolated positive equatorial Atlantic Niño event is a dipolar rainfall pattern in which the decrease of rainfall in Sahel is related to the in- crease of rainfall in Guinea (as in Fig. 4) due to changes in the sea–land pressure gradient between Gulf of Guinea SSTs and the Sahel. Mohino et al. (2011) and Rodríguez- Fonseca et al. (2011) have found in the observations how this dipolar behavior takes place for some particular decades coinciding with the SC periods, confirming in this way the correct determination of the leading co-variability mode by the model. When considering the EP period (Fig. 4, middle panels), a co-variability pattern similar to that observed for the SC period is appreciated with small differences. Regard- ing the predictand field, the anomalous rainfall signal is less intense when compared to SC. For the predictor, the cool- ing in the tropical Atlantic is accompanied by opposite weak anomalies in the north subtropical and tropical Pacific. Re- garding the NSC period (Fig. 4, bottom panels), as for the previous periods (SC, EP) a cooling in the tropical Atlantic is observed concerning the predictor associated with negative rainfall anomalies in the Gulf of Guinea and a weak positive signal in the eastern Sahel, virtually disappearing the rainfall
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Nitrate sources and dynamics in the salinized rivers and estuaries &ndash; a <i>&delta;</i><sup>15</sup>N- and <i>&delta;</i><sup>18</sup>O-NO<sub>3</sub><sup>&ndash;</sup> isotope approach

Nitrate sources and dynamics in the salinized rivers and estuaries &ndash; a <i>&delta;</i><sup>15</sup>N- and <i>&delta;</i><sup>18</sup>O-NO<sub>3</sub><sup>&ndash;</sup> isotope approach

the vicinity of the sampling area. The typically high δ 15 N-NO − 3 (13.6 to 15.0 ‰) values confirmed NO − 3 derivation from sewage. This point-source contamination was diluted by the estuarine water when salinity higher than 4.2, where the DIN concentrations and δ 15 N-NO − 3 values fall between the two mixing lines. The δ 18 O-NO − 3 values of the estu- arine water were quite close to the δ 18 O-NO − 3 derived from the nitrification of sewage,

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Comparing the efficacy of Truvada<sup>® </sup>and Kivexa<sup>® </sup>combination therapy in HAART-naive individuals with different viral loads

Comparing the efficacy of Truvada<sup>® </sup>and Kivexa<sup>® </sup>combination therapy in HAART-naive individuals with different viral loads

Earlier this year the Swiss Federal AIDS Commission published a paper stating that having an undetectable viral load made HIV positive people non-infectious. This position paper has incited intense controversy, being published against a background of increasing criminalisation of HIV transmission, difficulty of disclosure, and the psychological burden of living with a stigmatised and chronic illness.

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Geomorphic control on the &delta;<sup>15</sup>N of mountain forests

Geomorphic control on the &delta;<sup>15</sup>N of mountain forests

The Peruvian and Californian soil data are broadly con- sistent with the findings from Taiwan (Fig. 6). The Cal- ifornian data exhibit a significant negative correlation be- tween slope and δ 15 N (P = 0.007, n = 14) which is stronger than that reported for the inverse of slope (Amundson et al., 2003). On slopes steeper than sin θ = 0.35, the Peru- vian soil data (Townsend-Small et al., 2005) also exhibit a significant negative correlation between slope and δ 15 N (P = 0.004, n = 7). Plant samples from multiple species also mirror this trend (P = 0.05, n = 6). Like Taiwan, both lo- cations experience tectonic convergence, which builds steep topography and promotes high physical erosion rates (Bren- ner et al., 2001; Townsend-Small et al., 2008). However, on slopes sin θ < 0.35 the link between soil and plant δ 15 N val- ues and slope is not significant in the Andean forest (Fig. 6). The switch in behaviour is consistent with the threshold be- haviour of geomorphic processes (Roering et al., 1999) and the difference in overall erosion rates between these settings. In headwater catchments of the Andes, physical erosion rates have been estimated at 0.2–0.4 mm yr −1 (Safran et al., 2005), 10–20 times lower than those of the Central Range, Tai- wan (Dadson et al., 2003). Above ∼ 20 ◦ , the erosion rate
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Carbon isotope (δ<sup>13</sup>C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic

Carbon isotope (δ<sup>13</sup>C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic

It is still not possible to determine whether present-day gas emissions on the eastern part of the Vestnesa Ridge are sourced from below the GHSZ (gas hydrate stability zone), directly from dissociation of gas hydrates, or from a combi- nation of deeper and shallower processes (Bünz et al., 2012; Smith et al., 2014). It is also unclear whether focused fluid flow pathways from the base of the GHSZ have been estab- lished recently at the end of the last glaciation, or whether they have existed for much longer and have been reactivated multiple times. Even though this study has only documented two former events of increased emission at the western end of the Vestnesa Ridge, it favours a model of reactivation of chimney structures. The gas emissions and reactivation seem to occur during periods of climate change similar to obser- vations from the mid-Norwegian margin, where the gener- ation and initiation of focused fluid flow is most likely re- lated to an overpressure due to a combined effect of load- ing of glacigenic sediments and shelf ice glaciation (Hustoft et al., 2009b; Plaza-Faverola et al., 2011). However, the ini- tial generation of such chimney structures and their reactiva- tion might each be related to different geological processes. Chimneys are usually conceived as a network of connected small-scale fractures originating from natural hydraulic frac- turing (Arntsen et al., 2007). They represent pre-existing zones of weakness and open pathways that might facilitate fluid flow much more easily than during the initial genera- tion of the fracture network. In deep-water areas these frac- tures might be filled with gas hydrate (Kim et al., 2011).
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On the altitude dependence of transversely heated O<sup>+</sup> distributions in the cusp/cleft

On the altitude dependence of transversely heated O<sup>+</sup> distributions in the cusp/cleft

For any transverse heating event, restricted to the dayside cusp/cleft region for MLTs between 9.0 and 15.0 h, we keep the most energetic ion conics (e.g. those observed at the pole- ward edge of the heating region), as previously discussed in Sect. 2.2. For making intercomparison, ion moments, such as those of Fig. 3, are derived from ion distributions. Un- fortunately, for the Akebono/LEP database, used in Miyake et al. (1993), only the temperature and the apex angle of ion conics are available. Figure 4 shows the number of ion con- ics per altitude range and the scatterplots of ion moments as a function of geocentric distance r. In the present study, we have averaged CODIF ion distributions over 60 s, in order to make the number of data points of about the same order as for the Interball-2/Ion and Akebono/LEP databases. Dur- ing these events, the three Cluster satellites SC1, SC3, and SC4, on which CODIF data are available, are highly sepa- rated. The time lag with respect to the leading satellite SC4 is about 5 min and 40 min for SC1 and SC3, respectively. When comparing this time lag with typical times-of-flight of non-thermal O + ions (a few minutes for energies above
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The influence of temperature and seawater carbonate saturation state on <sup>13</sup>C–<sup>18</sup>O bond ordering in bivalve mollusks

The influence of temperature and seawater carbonate saturation state on <sup>13</sup>C–<sup>18</sup>O bond ordering in bivalve mollusks

Molluscan carbonate was amongst the first biologically pre- cipitated materials investigated during the development of the oxygen isotope paleotemperature scale (Epstein et al., 1953). Subsequently fossil mollusks have been widely used as an archive of past environmental change and seawater chemistry (e.g., Keith et al., 1964; Killingley and Berger, 1979; Grossman and Ku, 1986; Taviani and Zahn, 1998; Veizer et al., 1999; Tripati et al., 2001; Tripati and Zachos, 2002; Ivany et al., 2008; Wanamaker et al., 2011). How- ever it has proven challenging to develop robust independent paleothermometers in mollusk carbonate; for example, ap- proaches using trace element partitioning (Mg / Ca, Sr / Ca) into mollusk shell carbonate are often hampered by strong bi- ological controls and high inter- and intra-specimen variabil- ity (e.g., Dodd, 1965; Lorens and Bender, 1980; Klein et al., 1996; Gillikin et al., 2005; Freitas et al., 2006, 2008, 2009; Heinemann et al., 2011; Wanamaker et al., 2008). Therefore it has not yet been possible to reliably partition the contri- butions of temperature and seawater δ 18 O to bivalve mollusk carbonate δ 18 O with a high level of confidence in environ- ments where both parameters could be expected to vary.
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The <sup>3</sup>He flux gauge in the Sargasso Sea: a determination of physical nutrient fluxes to the euphotic zone at the Bermuda Atlantic time series site

The <sup>3</sup>He flux gauge in the Sargasso Sea: a determination of physical nutrient fluxes to the euphotic zone at the Bermuda Atlantic time series site

Within 24 h of sampling, the gas was extracted from the water stored in the cylinders into ∼ 30 mL aluminosilicate glass bulbs. The bulbs were then brought to the Isotope Geochemistry Facility at WHOI where they were analyzed for 3 He, 4 He, Ne, Ar, Kr, and Xe using a dual mass spectrometric system with the 3 He being analyzed by a magnetic sector mass spectrometer and the other noble gases being analyzed by a quadrupole

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Using <sup>14</sup>C and <sup>3</sup>H to understand groundwater flow and recharge in an aquifer window

Using <sup>14</sup>C and <sup>3</sup>H to understand groundwater flow and recharge in an aquifer window

Except for in June 2012 when the bores were overtopped, groundwater EC was constant throughout the study period and there is no inverse relationship to river height (Fig. 6). This indicates there is little exchange of river water to the depth of the aquifer sampled by the bores. Additionally the activities of 3 H in near-river bores are negligible, again suggesting that recharge from the river does not penetrate more than a few

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An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

Such mediums are the best cover media to hide messages. Digital images are the most widespread cover files used for SG, due to their high embedding efficiency and the insensitivity of the human visual system (HVS) [3]. It is not necessary that the cover and message have a homogeneous structure. For example, it is possible to embed a recording of an audio stream message inside a digital image [4]. The simplest steganographic techniques embed the bits of the message directly into the least significant bit (LSB) plane of the cover image in a deterministic sequence [5, 6]. Different steganographic techniques focus on a variety of requirements such as robustness, tamper resistance, imperceptibility, security and capacity [7-10]. Our technique is focused on providing high security and high speed operation while maintaining imperceptibility. We are using here Galois Encoder to provide high operational speed while maintaining the security intensively. The 2BC (two bit code) technique is the basic steganography technique we are using with the Galois Operation. Galois field arithmetic has received considerable attention in recent years due to their application in public-key cryptography schemes and error correcting codes.[12] We are here using the 2BC(two bit code) and Galois Field algorithm to achieve the goal of the maximum reception of the original message signal while maintaining the losses and enhancing the speed of operation. Different steganographic techniques focus on a variety of requirements such as robustness, tamper resistance, imperceptibility, security and capacity. Our embedding technique is focused on providing security while maintaining imperceptibility. Our method can work in any transform domain, but we are illustrating the ideas in the spatial domain for convenience. The rest of the paper is divided among the following sections: section 2 explains the existing passcode based technique which involves the matching process and the embedding techniques, section 3 describes the Galois operation, section 4 and 5 explains the data transmission and retrieval process using the Galois Encoder and decoder, section 6 contains simulation result and section 7 summarizes the Conclusion.
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Selection of the temperature of casting the bronzes to plaster moulds

Selection of the temperature of casting the bronzes to plaster moulds

The view of the drop of the solidification bronze on plaster mould and the fragments of plaster mould from the side of the contact with the melted drop show on Figure 8. Conducted analy- ses on station to the investigations of processes setting on the surface of the mould under the influence of the liquid bronze, in the normal weather condition of surroundings confirm that the considerable quantity of gases gives off in the process of the decomposition of the anhydrite. The large quantity of gas cavities testifies about this inside the drop of the solidification bronze on the surface of the plaster mould and characteristic shape and the colour of the surface of the plaster mould under the drop.
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An estimation of the <sup>18</sup>O / <sup>16</sup>O ratio of UT/LMS ozone based on artefact CO in air sampled during CARIBIC flights

An estimation of the <sup>18</sup>O / <sup>16</sup>O ratio of UT/LMS ozone based on artefact CO in air sampled during CARIBIC flights

Brenninkmeijer, C. A. M., Crutzen, P., Boumard, F., Dauer, T., Dix, B., Ebinghaus, R., Filippi, D., Fischer, H., Franke, H., Frieß, U., Heintzenberg, J., Helleis, F., Hermann, M., Kock, H. H., Koep- pel, C., Lelieveld, J., Leuenberger, M., Martinsson, B. G., Miem- czyk, S., Moret, H. P., Nguyen, H. N., Nyfeler, P., Oram, D., O’Sullivan, D., Penkett, S., Platt, U., Pupek, M., Ramonet, M., Randa, B., Reichelt, M., Rhee, T. S., Rohwer, J., Rosenfeld, K., Scharffe, D., Schlager, H., Schumann, U., Slemr, F., Sprung, D., Stock, P., Thaler, R., Valentino, F., van Velthoven, P., Waibel, A., Wandel, A., Waschitschek, K., Wiedensohler, A., Xueref-Remy, I., Zahn, A., Zech, U., and Ziereis, H.: Civil Aircraft for the reg- ular investigation of the atmosphere based on an instrumented container: The new CARIBIC system, Atmos. Chem. Phys., 7, 4953–4976, doi:10.5194/acp-7-4953-2007, 2007.
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137 Cs DE ÁREAS DE REFERÊNCIA

137 Cs DE ÁREAS DE REFERÊNCIA

magnitude, the observed variability can be attributed to: a) random spatial variability (inside each reference site) – this variability, expressed by the coefficient of varia- tion (CV%) of the average of the inventories of each site, varied from 11%, observed for site R1, to 31%, for site R2. Using the arbitrary categories established by Wild- ing & Drees (1983), mentioned by Sutherland (1996), these CV values would place the 137 Cs random spatial

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One year of <sup>222</sup>Rn concentration in the atmospheric surface layer

One year of <sup>222</sup>Rn concentration in the atmospheric surface layer

stant feature of the power spectrum as Fig. 2b seems to indicate. This is typically the case for the first week of March where the sudden decrease of concentration pro- duces large power variations at scales ranging from 1 to 10 h and extending over a time period of approximately 30 h. When the diurnal variation is not perturbed by exter- nal events, one can notice that the majority of small scale perturbations tend to occur

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An estimation of the <sup>18</sup>O / <sup>16</sup>O ratio of UT/LMS ozone based on artefact CO in air sampled during CARIBIC flights

An estimation of the <sup>18</sup>O / <sup>16</sup>O ratio of UT/LMS ozone based on artefact CO in air sampled during CARIBIC flights

Ramonet, M., Randa, B., Reichelt, M., Rhee, T. S., Rohwer, J., Rosenfeld, K., Scharffe, D., Schlager, H., Schumann, U., Slemr, F., Sprung, D., Stock, P., Thaler, R., Valentino, F., van Velthoven, P., Waibel, A., Wandel, A., Waschitschek, K., Wiedensohler, A., Xueref-Remy, I., Zahn, A., Zech, U., and Ziereis, H.: Civil Aircraft for the regular investigation of the at- mosphere based on an instrumented container: The new CARIBIC system, Atmos. Chem.

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J. Braz. Chem. Soc.  vol.10 número6

J. Braz. Chem. Soc. vol.10 número6

A his tó ria das re vis tas ci en tí fi cas bra si le i ras está re ple ta de al tos e ba i xos. Den tre as inú me ras que fo ram cri a das, pou cas con se gui ram so bre vi ver ao tem po, por uma ra zão mu i to sim ples: a so ci e da de bra si le i ra nun ca con si de rou seus pe rió di cos como ar qui vos de cul tu ra e como ins tru men to para ex pres sar a ciên cia fe i ta no país. Uma das ra zões dis to foi o pa drão de cul tu ra im pos to pela co lo ni za ção por tu gue sa, que nos obri ga va a ace i tar como de qua li da de tudo o que vi nha de além mar, amor da çan do, as sim, o nos so sen ti men to de li ber da de. Por isto, o Bra sil foi um dos úl ti mos pa í ses a co nhe cer a ti po gra fia. Vi ve mos boa par te da nos sa exis tên cia como na ção, como se não ti vés se mos pas sa do e com gran des di fi cul da des na sua cons tru ção. Fe liz men te, a re a li da de foi aos pou cos se al te ran do. Aos mais pes si mis tas é bom lem brar que a Re pú bli ca tem pou co mais de 100 anos e a So ci e da de Bra si le i ra de Qu í mi ca, me nos de 25 anos. Não fo ram mu i tos os que acre di ta ram que a SBQ pu des se se man ter viva por mais de dez anos e que pu des se cri ar e man ter três re vis tas, duas des tas in de xa das aos prin ci pa is ban cos de da dos da ciên cia mun di al e uma vol ta da to tal men te para a edu ca ção em Qu í mi ca. O pres tí gio da SBQ e de suas três re vis tas é uma pro va de que se pode cons tru ir o pas sa do, bas ta pla ne jar a ma te ri a li za ção do fu tu ro. É den tro des te es pí ri to que as no vas mu dan ças no Jour nal of the Bra zi li an Che mi cal So ci ety es tão sen do pla ne ja das para o pró xi mo mi lê nio, já com a in cor po ra ção de no vos edi to res. A re no va ção é uma das es tra té gi as para as se gu rar a con ti nu i da de da re vis ta.
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