31 research outputs found
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Northern Eurasia Future Initiative (NEFI): facing the challenges and pathways of global change in the 21st century
During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can
have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science
Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to
better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed
with regional decision makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and
models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include: warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land-use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia's role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large scale water withdrawals, land use and governance change) and
potentially restrict or provide new opportunities for future human activities. Therefore, we propose that Integrated Assessment Models are needed as the final stage of global
change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts
Performance Test of a Sensor Array-Based Odor Detection Instrument
Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 6 (2004): A. Yuwono and P. Schulze Lammers. Performance Test of a Sensor Array-Based Odor Detection Instrument. (May 2004)
Odor Pollution in the Environment and the Detection Instrumentation
Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 6 (2004): A. Yuwono and P. Schulze Lammers. Odor Pollution in the Environment and the Detection Instrumentation. (July 2004)
Kenngroessen der thermischen Gegenstromvergasung von Weizenstroh und ausgewaehlten Holzbrennstoffen
SIGLETIB: RA 4212 (98) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Detection of Root Biomass using Ultra Wideband Radar - an Approach to Potato Nest Positioning
Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Detection of Root Biomass using Ultra Wideband Radar - an Approach to Potato Nest Positioning. Manuscript IT 06 003. Vol. IX. May, 2007
Aplikacija herbicida direktnim injektiranjem u konceptu preciznog prskanja
A laboratory model for an direct injection system was designed for the
metering of appropriate herbicide into a carrier close to the nozzles. Two experiments
were performed to investigate the dynamic behavior of this system. In the first
experiment the position of the injection point was the center of a boom section and in the
second experiment the chemical ingredient was injected close the nozzle. For these
experiments a laboratory model of an injection sprayer system was employed. The
concentration of metered chemical ingredient was measured down-stream of the
injection point using a conductivity sensor based on sensing the electrical conductivity of
a salt solution. This sensor was developed for the evaluation of the system time response
characteristic of the sprayer.
The direct nozzle injection assembly provided a minimal response time from
injection point to nozzle tip with less than 2.8 s. The injection applied to a boom section
caused response time with a maximum of 7.5 s. This implies a maximum position error
of 6.8 to 16.7 m at 8 km h-1 forward speed of the sprayer with camera system for weed
detection.Labaratorijski model dirketnog injektorskog sistema je razvijen u smislu
odgovarajuće aplikacije herbicida u blizini radnog rasprkivača. Dva eksperimenta su
izvedena u cilju istraĹľivanja dinamike ovog sistema. U prvom, pozicija injekcione taÄŤke
je bila centar krila prskalice a u drugom hemikalija je injektirana u blizini rasprskivaÄŤa.
U svrhu ovog eksperimenta, labaratorisjki model injektorskog uređaja je upotrebljen.
Koncentracija aktivne supstance je merena ispod struje injekcione taÄŤke upotrebom
konduktivnog senzora baziranog na elektriÄŤnoj provodljivosti slanog rastvora. Ovaj
senzora je razvijen za procenu vremena odgovora sistema prskalice.
Uređaj za direktno injektiranje pokazuje minimalno vreme reakcije od injekcione
taÄŤke do vrha rasprskivaÄŤa, manje od 2.8 s. Injektiranje primenjeno na sekcijama krila
pokazalo je reaktivno vreme maksimalno do 7.5 s. Ovo implicira maksimalnu pozicionu
grešku od 6.8 do 16.7 m pri 8 km/h brzine prskalice sa detekcionim sistemom korova
snimanjem kamerom
Körnerfrucht mit Solardach trocknen
Um Getreide und Körnerleguminosen ohne den Einsatz fossiler Energieträger trocknen zu können, wurde 1991 auf dem Versuchsbetrieb für Organischen Landbau Wiesengut/Hennef der Universität Bonn eine Solarkollektorenanlage zur Warmlufterzeugung errichtet. Die Anlage ist seit 8 Jahren im Einsatz und hat sich im Erntebetrieb bewährt. Der Energieeinspareffekt bezogen auf den Gesamtbetrieb ist allerdings vergleichsweise gering, da die Anlage nur wenige Tage im Jahr zum Einsatz kommen kann. Im Falle einer Kombination mit einer Unterdach-Warmluft-Heutrocknung wäre eine höhere Auslastung und Investitionsdeckung gegeben.
aus: Haas, G. Bioland 05/200
Preservation of the donor–acceptor character of a carbazole–phenalenone dyad upon adsorption on Pt(111)
Donor–acceptor molecules are a subject of great attention due to their immense potential in molecular electronics and photovoltaics. Despite numerous extensive studies demonstrating their functionality in solution, the donor–acceptor character is usually lost upon adsorption on a conducting substrate. Here the concept of breaking the conjugation between the donor and acceptor unit by insertion of a bridge is used. Furthermore, the bridge introduces a kink into the dyad and thus, reduces the possibility of hybridization with the substrate. A donor–bridge–acceptor dyad composed of carbazole and phenalenone units joined through a flexible bridge is synthesized and deposited on a Pt(111) surface. Its electronic properties are investigated with a combination of low temperature scanning tunneling microscope measurements and density functional theory simulations. Two preferential adsorption configurations are identified, in which individual molecules form strong bonds to the substrate and to a Pt adatom. Differential conductance measurements and atomistic simulations evidence the preservation of a reduced donor–acceptor character upon adsorption of the molecule, where this reduction is ascribed to the strong molecule-metal hybridization. Our results highlight the changes in donor–acceptor character of the dyad induced by the substrate and provide guidelines for the use of donor–bridge–acceptor molecules as functional units in solid-state devices
Kenngroessen der thermischen Gegenstromvergasung von Weizenstroh und ausgewaehlten Holzbrennstoffen
SIGLEAvailable from Muenchen Technische Univ., Freising (DE). Inst. fuer Landtechnik / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman