Variación espacial y estacional de Cianobacterias y sus tasas de fijación de nitrógeno en la Bahía de Sanya en el Sur del Mar de China

The nitrogen fixation rates of planktonic and intertidal benthic cyanobacteria were investigated in Sanya Bay from 2003 to 2005. Trichodesmium thiebautii was the dominant species of planktonic cyanobacteria during our study. Significant seasonal and spatial variations in Trichodesmium spp. abundance were observed (P<0.01). The highest Trichodesmium concentrations occurred during intermonsoon periods and in the outer region of Sanya Bay (Outer Bay stations). At fixed station S03 the abundance of T. thiebautii ranged from 1.14×103 to 2060×103 trichomes m–2, with an annual mean of 273×103 trichomes m–2. The average nitrogen fixation rate per colony of T. thiebautii was 0.27 nmol N h-1 colony-1 and it did not show any obvious seasonal variations. Nitrogen fixation by planktonic cyanobacteria was highest in the Outer Bay stations, where the estimated amount of new nitrogen introduced by Trichodesmium contributed 0.03 to 1.63% of the total primary production and up to 11.64% of the new production. Statistical results showed that significant seasonal and spatial variations of nitrogen fixation rates were found among the intertidal communities. The main benthic nitrogen-fixing cyanobacteria were identified as members of the genera Anabaena, Calothrix, Lyngbya, Nostoc and Oscillatoria. The highest nitrogen fixation rate was found in microbial mats and the lowest in reefs and rocky sediments. All the benthic communities studied presented their highest nitrogen fixation activity in summer, with an average nitrogen fixation rate of 33.31 µmol N h-1 m-2, whereas the lowest nitrogen activity was detected in winter, with an average nitrogen fixation rate of 5.66 µmol N h-1 m-2. A Pearson correlation analysis indicated that the nitrogen fixation rate of three types of intertidal communities was significantly positively correlated to seawater temperature (P<0.05), whereas only the nitrogen fixation rate of the reefs and rock communities was significantly negatively correlated to seawater salinity (P<0.05).Las tasas de fijación de nitrógeno de cianobacterias intermareales y bentónicas fueron investigadas en la Bahía de Sanya, desde 2003 a 2005. Trichodesmium thiebautii era la especie dominante de las cianobacterias planctónicas durante nuestra investigación. Se observaron variaciones espaciales y estacionales significativas (P<0.01) en la abundancia de Trichodesmium spp. La concentración más elevada de Trichodesmium se observó durante los períodos de intermonzón y en la región exterior de la Bahía de Sanya (estaciones fuera de la Bahía). En la estación fija S03 la abundancia de T. thiebautii variaba desde 1.14×103 a 2060×103 tricomas m–2, con una media anual de 273×103 tricomas m–2. El promedio de la tasa de fijación de nitrógeno por colonia de T. thiebautii era de 0.27 nmol N h-1 colonia y no mostraba una clara variación estacional. La fijación de nitrógeno por las cianobacterias planctónicas era superior en las estaciones de fuera de la Bahía, donde la cantidad estimada de nitrógeno nuevo introducido por Trichodesmium contribuía del 0.03 al 1.63% del total de la producción primaria y hasta el 11.64% de la producción nueva. Estadísticamente los resultados mostraban que las variaciones espaciales y estacionales significativas de las tasas de fijación de nitrógeno fueron encontradas entre las comunidades intermareales. Las principales cianobacterias bentónicas fijadoras de nitrógeno fueron identificadas como miembros de los géneros Anabaena, Calothrix, Lyngbya, Nostoc y Oscillatoria. La tasa de fijación de nitrógeno más alta fue encontrada en los tapetes microbianos y las más bajas en los arrecifes y sedimentos rocosos. Todas las comunidades bentónicas estudiadas presentaban la mayor actividad de fijación de nitrógeno en verano, con un promedio de tasas de fijación de 33.31 ?mol N h-1 m-2, mientras que la menor actividad de fijación de nitrógeno fue detectada en invierno, con un promedio de 5.66 ?m N h-1 m-2. Análisis de correlación (Pearson) indicaban que las tasas de fijación de nitrógeno en los tres tipos de comunidades intermareales estaban significativamente correlacionados con la temperatura del agua (P<0.05). Mientras que la tasa de fijación de nitrógeno de las comunidades de los arrecifes y sedimentos rocosos estaban correlacionadas significativamente con la salinidad del agua de mar (P<0.05)

New isomers in 125 Pd 79 and 127 Pd 81 : Competing proton and neutron excitations in neutron-rich palladium nuclides towards the N=82 shell closure

The neutron-rich isotopes of palladium have attracted considerable interest in terms of the evolution of the neutron shell closure and its influence on the r-process nucleosynthesis. In this Letter, we present the first spectroscopic information on the excited states in 125Pd79 and 127Pd81 studied using the EURICA γ-ray spectrometer, following production via in-flight fission of a high-intensity 238U beam at the RIBF facility. New isomeric states with half-lives of 144(4) ns and 39(6) μs have been assigned spins and parities of () and () in 125Pd and 127Pd, respectively. The observed level properties are compared to a shell-model calculation, suggesting the competition between proton excitations and neutron excitations in the proton-hole and neutron-hole systems in the vicinity of the doubly magic nucleus 132Sn.Part of the WAS3ABi was supported by the Rare Isotope Science Project which is funded by MSIP and NRF of Korea. This work was supported by the Priority Centers Research Program in Korea (2009-0093817), OTKA contract number K100835, the U.S. DOE, Office of Nuclear Physics (Contract No. DE-AC02-06CH11357), NRF-2016R1A5A1013277 and NRF-2013M7A1A1075764, the Spanish Ministerio de Economía y Competitividad under contract FPA2017-84756-C4-2-P, the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011-IEF (Contract No. 300096), German BMBF under Contract No: 05P12PKFNE, JSPS KAKENHI Grant No. 24740188 and 25247045, the National Natural Science Foundation of China (Nos. 11505302, 11575112), the National Key Program for S&T Research and Development (No. 2016YFA0400501), and STFC (UK)

Mapping crop phenology using NDVI time-series derived from HJ-1 A/B data

With the availability of high frequent satellite data, crop phenology could be accurately mapped using time-series remote sensing data. Vegetation index time-series data derived from AVHRR, MODIS, and SPOT-VEGETATION images usually have coarse spatial resolution. Mapping crop phenology parameters using higher spatial resolution images (e.g., Landsat TM-like) is unprecedented. Recently launched HJ-1 A/B CCD sensors boarded on China Environment Satellite provided a feasible and ideal data source for the construction of high spatio-temporal resolution vegetation index time-series. This paper presented a comprehensive method to construct NDVI time-series dataset derived from HJ-1 A/B CCD and demonstrated its application in cropland areas. The procedures of time-series data construction included image preprocessing, signal filtering, and interpolation for daily NDVI images then the NDVI time-series could present a smooth and complete phenological cycle. To demonstrate its application, TIMESAT program was employed to extract phenology parameters of crop lands located in Guanzhong Plain, China. The small-scale test showed that the crop season start/end derived from HJ-1 A/B NDVI time-series was comparable with local agro-metrological observation. The methodology for reconstructing time-series remote sensing data had been proved feasible, though forgoing researches will improve this a lot in mapping crop phenology. Last but not least, further studies should be focused on field-data collection, smoothing method and phenology definitions using time-series remote sensing data

Determination of Material Strengths by Hydraulic Bulge Test

The hydraulic bulge test (HBT) method is proposed to determine material tensile strengths. The basic idea of HBT is similar to the small punch test (SPT), but inspired by the manufacturing process of rupture discs—high-pressure hydraulic oil is used instead of punch to cause specimen deformation. Compared with SPT method, the HBT method can avoid some of influence factors, such as punch dimension, punch material, and the friction between punch and specimen. A calculation procedure that is entirely based on theoretical derivation is proposed for estimate yield strength and ultimate tensile strength. Both conventional tensile tests and hydraulic bulge tests were carried out for several ferrous alloys, and the results showed that hydraulic bulge test results are reliable and accurate

Evaluation of the Multi-Angle Implementation of Atmospheric Correction (MAIAC) Aerosol Algorithm for Himawari-8 Data

Himawari-8, operated by the Japan Meteorological Agency (JMA), is a new generation geostationary satellite that provides remote sensing data to retrieve atmospheric aerosol optical depth (AOD) at high spatial (1 km) and high temporal (10 min) resolutions. The Geostationary- National Aeronautics and Space Administration (NASA) Earth exchange (GeoNEX) project recently adapted the multiangle implementation of atmospheric correction (MAIAC) algorithm, originally developed for joint retrieval of AOD and surface anisotropic reflectance with the moderate resolution imaging spectroradiometer (MODIS) data, to generate Earth monitoring products from the latest geostationary satellites including Himawari-8. This study evaluated the GeoNEX Himawari-8 ~1 km MAIAC AOD retrieved over all the aerosol robotic network (AERONET) sites between 6°N–30°N and 91°E–127°E. The corresponding JMA Himawari-8 AOD products were also evaluated for comparison. We only used cloud-free and the best quality satellite AOD retrievals and compiled a total of 16,532 MAIAC-AERONET and 21,737 JMA-AERONET contemporaneous pairs of AOD values for 2017. Statistical analyses showed that both MAIAC and JMA data are highly correlated with AERONET AOD, with the correlation coefficient (R) of ~0.77, and the root mean squared error (RMSE) of ~0.16. The absolute bias of MAIAC AOD (0.02 overestimation) appears smaller than that of the JMA AOD (0.05 underestimation). In comparison with the JMA data, the time series of MAIAC AOD were more consistent with AERONET AOD values and better capture the diurnal variations of the latter. The dependence of MAIAC AOD bias on scattering angles is also discussed

Research on Operation Optimization Technology of Integrated Energy System Based on Multiple Subjects

With the development of social economy and technology, the coupling relationship between different energy supply systems (cold, heat, electricity, gas, etc.) has become closer, and a comprehensive energy system with multiple subjects has become a development trend. In order to pursue a clean and efficient energy system, increase the consumption rate of new energy and reduce operating costs, a multiagent integrated energy system operation optimization method including combined heat and power (CHP) operators and photovoltaic user groups is proposed. In this paper, the distributed operation optimization method of integrated energy system based on multiple agents is studied. Considering the demand response of electric energy and thermal energy, and considering economy and user satisfaction, the distributed optimization scheduling model of integrated energy system with multiple agents is established to achieve the centralized optimization effect