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  • This is the revised version of Mars Missions Chronology published in Research Gate (2019). This Chronology contains the name of the spacecraft and their distinct names, type of the spacecraft, number of instruments carried, date of launch, launch vehicle, launch site, country and the manufacturer of the spacecraft. This chronology is arranged with reference to the number of spacecrafts launched from 1960 to 2020.
    Data Types:
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    • Document
  • SUMMARY Mimicry is ubiquitous in nature, yet understanding its origin and evolution is complicated by the scarcity of exceptional fossils that enable behavioural inferences about extinct animals. Here we report bizarre true bugs (Hemiptera) that closely resemble beetles (Coleoptera) from mid-Cretaceous amber. The unusual fossil bugs are described as Bersta vampirica gen. et sp. nov. and B. coleopteromorpha gen. et sp. nov., and are placed into a new family, Berstidae fam. nov. The specialised mouthparts of berstids indicate that they were predaceous on small arthropods and their striking beetle-like appearance implies that they mimicked beetles to attack unsuspecting prey; this unique association is not seen among extant insects and represents the first case of aggressive mimicry in the invertebrate fossil record. This rare example of fossilised behaviour enriches our understanding of the palaeoecological associations and extinct behavioural strategies of Mesozoic insects.
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  • Correct estimation of crop coefficients is essential to accurately assess water requirements of crops and thereby optimize irrigation management. The objectives of this study were (i) to quantify evapotranspiration and water use efficiency of potato crops grown in different locations and seasons in a semi-arid climate under irrigation, (ii) to estimate Kc values for these crops at different growth stages, and (iii) to assess the usefulness of the Penman-Monteith equation to estimate evapotranspiration and irrigation requirements. An eddy covariance system (ECV) was used in potato fields in three production regions of South Africa: the western Free State (summer crop), North West (spring crop) and Limpopo (winter crop). An IRGASON integrated open-path CO2/H2O gas analyzer - the ECV system (Campbell Scientific) was used to measure the H2O vapour fluxes above the crop canopy. It was integrated with a sonic anemometer, which measures the three-dimensional wind speed. Additional supporting sensors (fine wire thermocouple, NR-Lite net radiometer, silicon pyranometer, krypton hygrometer, CS616 reflectometer, Hukseflux heat flux plates) and a tipping bucket rain gauge were added to the system. Data were sampled at a frequency of 10 Hz, processed using EasyFlux DL software (Campbell Scientific), and recorded using a CR3000 datalogger. Seasonal mean crop evapotranspiration (ETc) was 4.6, 4.4 and 2.8 mm/day, respectively, for the summer, spring and winter crops. The reference evapotranspiration (ETo) correlated well with the daily patterns in ETc (r = 0.89, 0.56 and 0.76 for winter, spring and summer potato crops, respectively) and can be used for irrigation scheduling of potato. Seasonal mean Kc values varied considerably between the winter (1.00) and the spring (0.69) / summer (0.79) crops. This range is within the range reported from other parts of the world. The winter crop had the highest WUE of 3.2 kg dry potato tuber m3 of water evapotranspired, whilst WUE for the spring and summer crops was 2.9 and 2.2 kg/m3. The corresponding dry matter tuber yields were 12.0 t/ha (winter crop), 14.1 t/ha (spring crop) and 9.1 t ha/1 (summer crop). Our results suggest that ETo, which can be relatively easily estimated based on data from a weather station, can be used for irrigation scheduling of potato, but Kc values used to estimate crop evapotranspiration and irrigation requirements may need to be adjusted depending on the cropping season. Water use efficiency of potato was higher for the crop growing in the cooler winter compared to the crops growing in spring / summer. To optimize water use efficiency of potato in water-scarce areas that rely mostly on irrigation water for potato production, it is advisable to grow potato crops in the cooler season, outside the frost-prone period if possible.
    Data Types:
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    • Dataset
  • In this work, 0.3, 0.5, 1 and 1.5 wt.% concentration samples of MWCNT/water nanofluids have been prepared. Rheological behaviour of MWCNT/water nanofluids have been examined at different temperatures under the controlled shear stress of 0-35 Pa. Higher viscosity results were found for higher concentration nanofluids.
    Data Types:
    • Tabular Data
    • Dataset
  • This data set includes the method for calculating elastic modulus, relevant figures, detailed mechanical parameters and chemical components of the tested indentation areas.
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    • Tabular Data
    • Dataset
    • Document
  • Photogrammetric data for Apollo 12 landing site: coordinates of camera stations, selected objects on the surface, map, *.rzi files with raw data for ImageModeler. It is based on Hasselblad photographs made by the crew during their EVAs. Positions of camera stations, artifacts (Lunar Module, Surveyor 3 space probe, ALSEP instruments ets) and landscape features were determined.
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  • Correct estimation of crop coefficients is essential to accurately assess water requirements of crops and thereby optimize irrigation management. The objectives of this study were (i) to quantify evapotranspiration and water use efficiency of potato crops grown in different locations and seasons in a semi-arid climate under irrigation, (ii) to estimate Kc values for these crops at different growth stages, and (iii) to assess the usefulness of the Penman-Monteith equation to estimate evapotranspiration and irrigation requirements. An eddy covariance system (ECV) was used in potato fields in three production regions of South Africa: the western Free State (summer crop), North West (spring crop) and Limpopo (winter crop). An IRGASON integrated open-path CO2/H2O gas analyzer - the ECV system (Campbell Scientific) was used to measure the H2O vapour fluxes above the crop canopy. It was integrated with a sonic anemometer, which measures the three-dimensional wind speed. Additional supporting sensors (fine wire thermocouple, NR-Lite net radiometer, silicon pyranometer, krypton hygrometer, CS616 reflectometer, Hukseflux heat flux plates) and a tipping bucket rain gauge were added to the system. Data were sampled at a frequency of 10 Hz, processed using EasyFlux DL software (Campbell Scientific), and recorded using a CR3000 datalogger. Seasonal mean crop evapotranspiration (ETc) was 4.6, 4.4 and 2.8 mm/day, respectively, for the summer, spring and winter crops. The reference evapotranspiration (ETo) correlated well with the daily patterns in ETc (r = 0.89, 0.56 and 0.76 for winter, spring and summer potato crops, respectively) and can be used for irrigation scheduling of potato. Seasonal mean Kc values varied considerably between the winter (1.00) and the spring (0.69) / summer (0.79) crops. This range is within the range reported from other parts of the world. The winter crop had the highest WUE of 3.2 kg dry potato tuber m3 of water evapotranspired, whilst WUE for the spring and summer crops was 2.9 and 2.2 kg/m3. The corresponding dry matter tuber yields were 12.0 t/ha (winter crop), 14.1 t/ha (spring crop) and 9.1 t ha/1 (summer crop). Our results suggest that ETo, which can be relatively easily estimated based on data from a weather station, can be used for irrigation scheduling of potato, but Kc values used to estimate crop evapotranspiration and irrigation requirements may need to be adjusted depending on the cropping season. Water use efficiency of potato was higher for the crop growing in the cooler winter compared to the crops growing in spring / summer. To optimize water use efficiency of potato in water-scarce areas that rely mostly on irrigation water for potato production, it is advisable to grow potato crops in the cooler season, outside the frost-prone period if possible.
    Data Types:
    • Tabular Data
    • Dataset
  • In this work, the attapulgite (ATP) was used as a promising mineral clay to prepare polyamide 12 (PA12) matrix polymer nanocomposites. ATP has a relatively low cost compared to other nanoclays and is a very abundant raw material in the northeast region of Brazil. The ATP was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy and field emission gun scanning electron microscopy (FEG-SEM). The PA12/ATP nanocomposites with 0, 1, 2.5, 5, 7.5 and 10 wt% of ATP were prepared using a simple blending method in a high-speed thermokinetic homogenizer (3000 rpm) in which the melting of the PA12 and the mixture with ATP occurred by friction, followed by hot pressing and stamping of the specimens. The nanocomposites were characterized by mechanical properties, the degree of crystallinity and crystallite size were calculated by XRD, and the morphological characteristics were observed by SEM. The addition of ATP in the PA12 matrix increased the modulus of elasticity, hardness, degree of crystallinity and the apparent crystallite size of the nanocomposites. The addition of up to 5 wt% of ATP increased tensile strength and deformation at break; for higher concentrations, the dispersion was not efficient. A major advantage of using ATP as a reinforcement agent for PA12 is the low cost of this material plus the great interaction with PA12 which can dispense the use of compatibilizer agents and/or surface modification in the ATP, making it a potential material to extend PA12’s range of applications.
    Data Types:
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    • Document
  • The database contains cross-border exposures (as a % of total exposures) to individual countries for the 61 largest European banks over the years 2010-2015. Getting a complete overview of the cross-border positions of European banks is challenging, as there are no regular reporting standards for banks’ foreign exposures split by country. One option is to focus on banks’ foreign subsidiaries. This may however lead to a significant underestimation of a bank’s foreign activities, especially since European banks conduct around half of their foreign activities vis branches. With this dataset we aim to provide a more complete picture of banks' cross-border exposures and collected the data ourselves from public sources. We collected the data for the 61 largest European banks. These banks together represent around two-third of total European banking assets. The 61 banks together invest in 138 different countries (the countries are presented by their ISO2 codes). Data on cross-border exposures are primarily obtained from annual reports, and, when needed, supplemented with data stemming from the public EBA stress tests conducted in 2011 and 2013, and CRD IV country-by-country reporting.Due to the absence of a standard reporting format some assumptions and simplifications had to be made. First of all, the majority of banks report their foreign exposures in loans or assets, but some banks use the net income as the reporting unit. As we are especially interested in banks’ credit exposures to other countries, we had an order of preference for exposures reported in i) loans; ii) assets; and iii) net income. Second, we aimed for cross-border exposures at the country level as for our analysis we link home and host country characteristics. However, sometimes only information on banks’ exposures to a group of countries (e.g. Western Europe) or continents (e.g. Asia) was available. In those cases, we simply reported the exposures to groups of countries or continents (see columns EN-EX in the database). Third, the data collection resulted in an almost complete overview of the foreign exposures of the 61 European banks. For only a small portion of foreign exposures (3.6% of the total foreign exposures or 1.1% of the total assets) we do not know to which region or country these belong . This is the case when banks report their remaining foreign exposures as “other” without mentioning the countries belonging to this group (here we used "in-sample" estimation). Note that it also happens that a bank reports about its cross-border exposures quite granular for one year (i.e. exposures to multipe individual countries), and the subsequent year only reports the total exposures to "rest of europe" and "america". In those cases information from the years with granular information is used to make assumptions about the other years' cross-border exposures.
    Data Types:
    • Tabular Data
    • Dataset
  • We present new geochronological, whole-rock geochemical data, and zircon Hf isotopic data from middle Permian to Middle Jurassic igneous rocks that occur near the Changchun-Yanji Suture in the area of Jilin city. These new data can (1) constrain the timing of magmatism and elucidate the spatio-temporal distribution of magmatism; (2) characterize the petrogenesis of the igneous rocks and their possible sources; and (3) provide new insights into the tectonic setting during magmatism. Together with geological evidence from this area allow us to better understand the transition in the tectonic regime during the Late Paleozoic and Mesozoic. Based on zircon U–Pb ages and geochemical data, the following conclusions are drawn. 1. Middle Permian to Middle Jurassic igneous rocks in the area of Jilin were emplaced during four major phases, at ca. 261 Ma, 253–244 Ma, 183–175 Ma, and 173–164 Ma. 2. The earliest phase of magmatism, at ca. 261 Ma, was generated in an active continental margin by partial melting of juvenile mafic lower crustal material. Magmatism at 253–244 Ma was generated in a continental arc environment by partial melting of juvenile mafic subducted oceanic crust. At 183–175 Ma, monzogranitic and dioritic magmas were generated in a continental arc environment via melting of juvenile lower continental crust and mixing of basaltic magma with crustal melt, respectively. The final stage of magmatism, at 173–164 Ma, formed in an active continental margin, generated by melting of juvenile lower continental crust. 3. Integrated evidence suggests that the closure of the Paleo-Asian Ocean could occur at 244–227 Ma, whereas the timing of tectonic regime transition from the influence of Paleo-Asian Ocean subduction to the subduction of the Paleo-Pacific Ocean occurred between Late Triassic and Early Jurassic (223–185 Ma). 4. The Changchun-Yanji Suture experienced multiple tectonic mode switches from Late Paleozoic to Mesozoic, and was controlled by subduction of the Paleo-Pacific Ocean since Early Jurassic.
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    • Document
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