374 research outputs found
Exploring pathways for sustainable water management in river deltas in a changing environment
Exploring adaptation pathways into an uncertain future can support decisionmaking in achieving sustainable water management in a changing environment. Our objective is to develop and test a method to identify such pathways by including dynamics from natural variability and the interaction between the water system and society. Present planning studies on long-term water management often use a few plausible futures for one or two projection years, ignoring the dynamic aspect of adaptation through the interaction between the water system and society. Our approach is to explore pathways using multiple realisations of transient scenarios with an Integrated Assessment Meta Model (IAMM). This paper presents the first application of the method using a hypothetical case study. The case study shows how to explore and evaluate adaptation pathways. With the pathways it is possible to identify opportunities, threats, timing and sequence of policy options, which can be used by policymakers to develop water management roadmaps into the future. By including the dynamics between the water system and society, the influence of uncertainties in both systems becomes clearer. The results show, among others, that climate variability rather than climate change appears to be important for taking decisions in water management
High sensitive quasi freestanding epitaxial graphene gassensor on 6H-SiC
We have measured the electrical response to NO, N, NH and CO for
epitaxial graphene and quasi freestanding epitaxial graphene on 6H-SiC
substrates. Quasi freestanding epitaxial graphene shows a 6 fold increase in
NO2 sensitivity compared to epitaxial graphene. Both samples show a sensitivity
better than the experimentally limited 1 ppb. The strong increase in
sensitivity of quasi freestanding epitaxial graphene can be explained by a
Fermi-energy close to the Dirac Point leading to a strongly surface doping
dependent sample resistance. Both sensors show a negligible sensitivity to
N, NH and CO
Захисні лісові насадження – важливий структурний елемент у формуванні національної екологічної мережі
Описано роль і значення захисних лісових насаджень як важливого структурного елементу при формуванні національної екологічної мережі.Описана роль и значение защитных лесных насаждений как важного структурного элемента при формировании национальной экологической сети.Role and meaning of forest protective stands as an important structural element for national ecological network formation is described
Direct magneto-optical compression of an effusive atomic beam for high-resolution focused ion beam application
An atomic rubidium beam formed in a 70 mm long two-dimensional
magneto-optical trap (2D MOT), directly loaded from a collimated Knudsen
source, is analyzed using laser-induced fluorescence. The longitudinal velocity
distribution, the transverse temperature and the flux of the atomic beam are
reported. The equivalent transverse reduced brightness of an ion beam with
similar properties as the atomic beam is calculated because the beam is
developed to be photoionized and applied in a focused ion beam. In a single
two-dimensional magneto-optical trapping step an equivalent transverse reduced
brightness of A/(m sr eV) was
achieved with a beam flux equivalent to nA. The
temperature of the beam is further reduced with an optical molasses after the
2D MOT. This increased the equivalent brightness to A/(m sr eV). For currents below 10 pA, for which disorder-induced
heating can be suppressed, this number is also a good estimate of the ion beam
brightness that can be expected. Such an ion beam brightness would be a six
times improvement over the liquid metal ion source and could improve the
resolution in focused ion beam nanofabrication.Comment: 10 pages, 8 figures, 1 tabl
Frozen thermal fluctuations in adsorbate-induced step restructuring
Ammonia adsorbed on a Pt(443) surface causes meandering of the initially straight edges at 300 K. Based on density-functional theory calculations and on kinetic Monte Carlo simulations it is shown that the meandering is not an equilibrium structure stabilized by the larger adsorption energy of ammonia at step and kink sites. Rather the meandering has to be interpreted as a frozen thermal fluctuation caused by ammonia which strongly reduces the stiffness of the step edges at intermediate ammonia coverages
Совершенствование региональных целевых программ – инструмента управления социально-экономическим развитием Одесского региона и его конкурентоспособностью
Розглянуто регіональні цільові програми розвитку Одеського регіону; виявлено недоліки діючого підходу до розробки й оцінки програм на регіональному рівні; подано рекомендації щодо загальних підходів до програмного управління, експертизи проектів; запропоновано експертний метод оцінки ефективності цільових програм із точки зору управління процесом розробки та реалізацією програм, своєчасного прийняття рішень.
Ключові слова: регіональні цільові програми, соціально-економічний розвиток, регіон,
управління, конкурентоспроможність.Рассмотрены региональные целевые программы развития Одесского региона; выявлены недостатки действующего подхода к разработке и оценке программ на региональном уровне; даны рекомендации по общим подходам к программному управлению, экспертизе проектов; предложен экспертный метод оценки эффективности целевых программ с точки зрения управления процессом разработки и ходом реализации программ, своевременного принятия решений.
Ключевые слова: региональные целевые программы, социально-экономическое развитие, регион, управление, конкурентоспособность.The paper considers the regional target programs of Odessa region development. Shortcomings of the present approach to the development and evaluation of programs at the regional level are shown, recommendations on common approaches to program management and project appraisal are given; expert method for evaluating target programs is proposed from the view of managing the process of development and implementation of programs, timely decisions.
Keywords: regional target programs, socio-economic development, region, management, competitiveness
Boosting the Figure Of Merit of LSPR-based refractive index sensing by phase-sensitive measurements
Localized surface plasmon resonances possess very interesting properties for
a wide variety of sensing applications. In many of the existing applications
only the intensity of the reflected or transmitted signals is taken into
account, while the phase information is ignored. At the center frequency of a
(localized) surface plasmon resonance, the electron cloud makes the transition
between in- and out-of-phase oscillation with respect to the incident wave.
Here we show that this information can experimentally be extracted by
performing phase-sensitive measurements, which result in linewidths that are
almost one order of magnitude smaller than those for intensity based
measurements. As this phase transition is an intrinsic property of a plasmon
resonance, this opens up many possibilities for boosting the figure of merit
(FOM) of refractive index sensing by taking into account the phase of the
plasmon resonance. We experimentally investigated this for two model systems:
randomly distributed gold nanodisks and gold nanorings on top of a continuous
gold layer and a dielectric spacer and observed FOM values up to 8.3 and 16.5
for the respective nanoparticles
Charge recombination in a poly(para-phenylene vinylene)-fullerene derivative composite film studied by transient, nonresonant, hole-burning spectroscopy
Transient, nonresonant, hole-burning spectroscopy was used to study the charge recombination process in poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1-4-phenylene vinylene] (MDMO-PPV):methanofullerene (PCBM) composite films. The position and intensity of the spectral hole in the absorption band of MDMO-PPV were monitored as a function of time in the 10 ns-10 ms time range. A time-dependent red shift was obsd. The intensity of the spectral hole decayed with time according to a power law (~t-a). The exponent a ~ 0.5 is nearly independent of the excitation fluence in the range 0.05-2 mJ/cm2. The depth of the spectral hole depends sublinearly on the excitation fluence (I) and can be described by (~G-b) with b.apprx.0.5. The time-dependent red shift and the power-law type time decay can be reproduced by numerical simulations. The Monte Carlo method is used to simulate the hopping dynamics of the photoinduced charges in a lattice of energetically disordered sites before they eventually recombine at the MDMO-PPV:PCBM interface. Charge sepn. is assisted by disorder and, in the 10 ns-10 ms time range, the recombination rate is limited by the detrapping of the cationic charge carriers in MDMO-PP
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