46 research outputs found
RAPIDEYE - An Earth Observation Smallsat Constellation for Daily Agricultural Monitoring
No full textThe RapidEye mission is a commercial remote sensing mission by the German company Rapi-dEye AG. The RapidEye mission will deliver information products for various customers in the agricultural insurance market, large producers, international institutions and cartography. The mission that generates these information products consists of a constellation of five identical small satellites and a sophisticated ground infrastructure based on proven systems. The five satellites will be placed in a single sun-synchronous orbit of approximately 620 kilome-ters, with the satellites equally spaced over the orbit. The satellites will each carry a 5 band multi-spectral optical imager with a ground sampling distance of 6.5 meters at nadir and a swath width of 80 km. The RapidEye system has the unique ability to image any area on earth once per day and can also provide large area coverage within 5 days. This capability along with the proc-essing throughput of the ground segment allows the system to deliver the information products needed by the customers reliably and in a time frame that meets their specific needs. Dr
Enteromorpha prolifera-derived carbon as a high-performance cathode material for lithium–sulfur batteries
No full textSelf-assembled twine-like Na2Ti3O7 nanostructure as advanced anode for sodium-ion batteries
No full textSodium-ion batteries (SIBs) have attracted growing interest due to their cost-effectiveness compared with lithium-ion batteries counterparts. Exploring anode materials with outstanding performance is a persistent objective with the development of SIBs. Herein, we report a compound of Na2Ti3O7 with twine-like three-dimension (3D) network framework synthesized via a facile stirring hydrothermal method. The resulting material has a unique structure with elongated one-dimensional nanotubes, ultrathin tube wall, large surface area, numerous -OH group as well as twine-like winding body. The cell assembled with Na2Ti3O7 as anode active material manifests excellent cycling performance (77% capacity is retented after 1000 cycles at 10 C) and superior rate capability (80 mA h g(-1) is kept even at ultra-high current rate of 50 C). The special structure endows the material with superior electrochemical properties and great potential application in SIBs. (C) 2016 Elsevier B.V. All rights reserved
Preparation and evaluation of a separator with an asymmetric structure for lithium-ion batteries
No full textThe different electrochemical characteristics stemming from the cathode and anode of lithium-ion batteries may have different effects on the surface properties of contacted separators. Herein, a series of composite separators with an asymmetric porous structure are fabricated by a one-step phase inversion method coupled with the settling of SiO2 nanoparticles due to gravity within the poly(vinylidenefluorideco-hexafluoropylene) (PVDF-HFP) polymer matrix. The unique asymmetric porous separators are composed of a PVDF-HFP-rich layer with high porosity on the front surface, which is in contact with the air, and a SiO2-rich layer on the back surface, which is in contact with the substrate. Besides their excellent thermal stability and high safety towards fire, these asymmetric porous separators result in a high discharge capacity, enhanced cycling performance and excellent rate capability when assembled with a LiNi0.5Mn1.5O4 cathode in coin cells, indicating that the asymmetric porous composite separators could be a promising candidate to improve the performance of lithium-ion batteries
Diseño de un sistema fotovoltaico híbrido para reducir costos de iluminación eléctrica en una empresa láctea en Arequipa
No full textEl presente estudio tuvo como objetivo principal diseñar un sistema fotovoltaico
híbrido para reducir los costos de iluminación eléctrica en la empresa Laive S.A. Se
empleó unametodología aplicada, con diseño no experimental y método descriptivo.
El diseño del sistema busca mejorar la sostenibilidad económica de la empresa al
disminuir su dependencia de la red eléctrica convencional, contribuyendo al ODS 7:
Energía asequible y no contaminante.
El sistema se compone de 72 paneles solares monocristalinos marca Tensite con
tecnología PERC de 24V y potencia pico de 550 Wp, 3 inversores híbridos marca
Deye, modelo SUN-10K-SG02LP1-AU-AM3 de 10kW, 72 baterías en gel de 300Ah y
12Vmarca Tensite, modeloGEL 12-300 y unaprofundidadde descarga del 70%. Los
conductores y sistemas de protección se seleccionaron en función de la corriente y
distancia en cada tramo del sistema.
Se concluyó que el diseño del sistema solar fotovoltaico híbrido tiene el potencial de
generar un ahorroanual de S/. 14.283,59. La inversión total asciende a S/. 248.284,31
incluyendo los equipos, instalación y puesta en marcha, con un periodo de retorno de
inversión estimado en aproximadamente 12 años
Improved Performance of LiFe0.25Mn0.75PO4 by using Graphene and Fluorine- Doped Carbon Coating
No full textLithium transition metal phosphatesusually need modification of morphology and electron
conductivity for improving the electrochemical performance [1,2]. In this work, the electron
conductivity of LiFe0.25Mn0.75PO4 is increased by adopting graphene and F-doped carbon.The reductive graphene oxide and F-doped carbon coating LiFe0.25Mn0.75PO4 (LFMP/C-F/rGO) is synthesized by a simple ball milling method
The discovery of early Paleoproterozoic high-Na trondhjemite in the northeastern Qaidam basin: Evidence from the drilling core samples
No full textDeye 1 Well (DY 1 Well) completed in 2013 is the first drilling well that reached the early Paleoproterozoic crystalline basement in the northeastern Qaidam basin. This paper analyzes the drilling core samples from DY 1 Well. Petrology and geochemistry indicate that the drilling core samples belong to high-Na trondhjemite. LA-ICP-MS zircon dating for the drilling core samples yields a weighted mean (207)pb/Pb-206 age of 2383.1 +/- 6.3 Ma, which is consistent with its upper interception age. Meanwhile, the geochemical characteristics and the deformation degree of high-Na trondhjemite are significantly different from its adjacent gneisses and the Mohe quartz-dioritic rocks in the Quanji Massif. It implies that the basement of the Qaidam basin under thick Cenozoic sediments may be different from its surrounding outcrops, and differential crustal attributes lead to intensely differential Cenozoic vertical motions between basins and mountains. Meanwhile, the widespread familiarity between the Qaidam and Tarim basins implies that the basement of the Qaidam basin may be a part of the Tarim Block during the Precambrian. (C) 2017 Elsevier B.V. All rights reserved.China Postdoctoral Science Foundation [2016M590016]; National Science and Technology Major Project [2017ZX05008-001]SCI(E)ARTICLE615-62829
The Effects of a Mixed Precipitant on the Morphology and Electrochemical Performance of LiNi0.5Mn1.5O4 Cathode Materials
No full textA series of LiNi0.5Mn1.5O4 (LNMO) samples were synthesized by adjusting the molar ratio of (NH4)(2)CO3 to Na2CO3 in a mixed precipitant for evaluating the effects of ammonia from (NH4)(2)CO3 as a complexing agent and Na2CO3 as a precipitant on the morphology and electrochemical performances of LNMO. In this research, a rapid precipitation method followed by hydrothermal treatment was used to prepare the precursors of LNMO, and different molar ratios (0:1, 1:2, 1:1, 2:1, 1:0) of (NH4)(2)CO3 to Na2CO3 were used for mixed precipitants. The test results revealed that the cathode material exhibits the best electrochemical performance when the molar ratio of (NH4)(2)CO3 to Na2CO3 is set at 1:2, displaying a specific discharge capacity of 129.4 mA h g(-1) at 0.5 C and a capacity retention of 82.3% after 200 charge-discharge cycles. In addition, it still shows a high rate performance with a discharge capacity of 112.7 mA h g(-1) at 10 C and 98.8 mA h g(-1) at 20 C, which is attributed to an accurate Ni/Mn ratio, smaller primary particle sizes and a porous spherical morphology
Yesterday, Tomorrow
No full text’Yesterday, Tomorrow’ is based on Nuruddin Farah’s book, Yesterday, Tomorrow: Voices from the Somali Diaspora. It is a portrayal of the personal stories of people who, due to political instability in postcolonial Somalia, find themselves forced to flee their homes, cross borders and become refugees. Loss, borders and politics are at the very centre of this piece. This staged reading brings to mind the 125th anniversary of the Berlin Conference, where Bismarck invited 13 other European governors to divide the African continent into a series of colonial states and illogical borders, laying the framework for more than a century of civil strife. The individual stories and subtle portraits of the countries of exile create a moving image of life between different worlds.Playwright Amy Evans seeks through her work to critically examine the impact of displacement, alienation and political violence on the human spirit. Her first play, Achidi J’s Final Hours, was inspired by the true story of Mareame N’Deye Sarr, a young woman who was killed in a confrontation with German police in Aschaffenburg in July 2001. Her newest play, The Most Unsatisfied Town, based on the death-in-custody of Oury Jalloh, was completed while in residency at the ICI Berlin earlier this year. Grada Kilomba’s literary works explore the fields of memory, trauma and post-colonialism. Among others, she is the author of Plantation Memories (2008) a compilation of episodes of everyday racism written in the form of short psychoanalytical stories. Currently she is a fellow at the ICI Berlin, where she is writing her new book Kalunga based on the Orishas and the post-transatlantic experience of fragmentation, loss and colonial convalescing. Michael Edode Ojake (actor) was born in 1961 in Lagos, Nigeria. He was a production assistant at the National Theatre in Lagos and studied Acting at the Academy of Theatre and Film in Sofia, Bulgaria. Since 1990 he lives and works in Berlin as an actor, director and author in film and theatre. Araba Walton is a German actress and singer. She worked for five years with a number of theatre companies in London, until an engagement with the Musical ‘The Lion King’ brought her back to her home country. Currently she has a capital role in the movie ‘Berlin Calling’. Nuruddin Farah is one of the most acclaimed contemporary writers. Born in 1945 in Baidoa, Somalia. Farah was sentenced to death in absentia for political reasons in 1976. After spending many years in exile in Africa, Europe and the U.S., he now lives in Cape Town, South Africa. He is the winner of the prestigious Neustadt Prize for Literature (1998) and a perennial nominee for the Nobel Prize for Literature. He is the author of numerous novels, including the Blood in the Sun-trilogy. His work has been translated into 17 languages. Knots is his latest novel.
Literary Adaptation: Amy Evans and Grada Kilomba Artistic Direction: Grada Kilomba This staged reading had its premiere at the Haus der Kulturen der Welt on 2 December 2009
Preparation and evaluation of high lithium ion conductivity Li1.3Al0.3Ti1.7(PO4)(3) solid electrolyte obtained using a new solution method
No full textA NASICON-type (Na ion super conductor) structured Li1.3Al0.3Ti1.7(PO4)(3) (LAW) solid electrolyte with high lithium ion conductivity was synthesized using a simple solution method with 85% H3PO4 solution. In comparison with conventional solid-state reaction and sol-gel method, the pure LATP powders and dense LATP pellets were obtained at a relatively lower temperature. The LATP powders and the resultant pellets were characterized by X-ray diffraction, scanning electron microscopy (SEM) and AC impedance spectroscopy. The LATP pellet obtained at 800 degrees C for 12 h shows the highest total conductivity of 1.21 x 10(-3) S cm(-1) at room temperature and the lowest activation energy of 0.26 eV. These results imply that the LAW electrolytes obtained using this method can be considered as candidates for solid state electrolytes. (C) 2016 Elsevier B.V. All rights reserved
