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991.
The economic impacts on developing regions following a global cap and trade system for carbon dioxide are assessed through the use of an energy-economy systems model. Both an equal per capita allocation and a contraction and convergence allocation with convergence of the per capita emissions by 2050 are shown to offer economic incentive for Africa, India and probably also Latin America to accept binding emissions commitments under a 450 ppm carbon dioxide stabilization scenario. The gain for Latin America is mainly a result of increased export revenues from sales of bio-fuels as a result of the climate policy. It is, on the other hand, unlikely that these allocation approaches would offer an economic incentive for China to join the regime because of its high economic growth, present higher per capita emissions than India and Africa, and more costly mitigation options than Latin America. A more stringent allocation for developing countries such as contraction with convergence of the per capita emissions by the end of this century is estimated to generate reduced net gains or increased net losses for the developing regions (though Africa is still expected to gain). 相似文献
992.
Yong Hyun Kim Christoph Sachse Michael L. Machala Christian May Lars Müller‐Meskamp Karl Leo 《Advanced functional materials》2011,21(6):1009-1009
Highly conductive poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films as stand‐alone electrodes for organic solar cells have been optimized using a solvent post‐treatment method. The treated PEDOT:PSS films show enhanced conductivities up to 1418 S cm?1, accompanied by structural and chemical changes. The effect of the solvent treatment on PEDOT:PSS has been investigated in detail and is shown to cause a reduction of insulating PSS in the conductive polymer layer. Using these optimized electrodes, ITO‐free, small molecule organic solar cells with a zinc phthalocyanine (ZnPc):fullerene C60 bulk heterojunction have been produced on glass and PET substrates. The system was further improved by pre‐heating the PEDOT:PSS electrodes, which enhanced the power conversion efficiency to the values obtained for solar cells on ITO electrodes. The results show that optimized PEDOT:PSS with solvent and thermal post‐treatment can be a very promising electrode material for highly efficient flexible ITO‐free organic solar cells. 相似文献
993.
Realization of the cloud computing infrastructure requires access to data anywhere, anytime at any device at a sufficient
perceived quality of service. Many Western European countries, such as Denmark, have a high percentage of individuals (inhabitants
and companies) that has access to broadband internet via cable, satellite and mobile. This gives a unique position in roll-out
and deploying intelligent cloud based services that can be applied for a number of purposes, but where lack of sufficient
capacity/quality and IT readiness will be barriers in realization of the “Global Information Multimedia Communication Village
(GIMCV)”. Broadband is here defined as more than 2 Mbps. In this paper, the combination of e-commerce, cloud computing and
broadband infrastructure has our focus, and its unique possibilities for the overall IT society. However, it is also about
a significant number of Small and Medium sized Enterprises (SMEs) that today applies manual billing systems or Excel like
systems in combination with severe lacks of sufficient IT skills. This means that the most commonly used systems are the ones
requiring the most of our time. Therefore, the move for the SME towards e-commerce and electronic processes has a significant
economical potential for the SMEs. E-commerce and other internet based services will simplify their business, and hence allow
the SMEs to focus on their core business which was their raison d’être. In addition to this can be added other fundamental
IT systems that will help their business, but that is outside the scope of this paper. Furthermore, this paper focuses on
infrastructural barriers and cloud computing; not only focusing on bandwidth, but also the entire issue of service offering.
Services offered via cloud computing solutions will minimize the SMEs investment in own hardware (HW), software (SW) and maintenance.
The focus is also the upgrade to a superior infrastructure that provides the platform for efficient cloud computing, for e-commerce,
and beyond. 相似文献
994.
Santucci SC Cojoc D Amenitsch H Marmiroli B Sartori B Burghammer M Schoeder S DiCola E Reynolds M Riekel C 《Analytical chemistry》2011,83(12):4863-4870
Investigations of single fragile objects manipulated by optical forces with high brilliance X-ray beams may initiate the development of new research fields such as protein crystallography in an aqueous environment. We have developed a dedicated optical tweezers setup with a compact, portable, and versatile geometry for the customary manipulation of objects for synchrotron radiation applications. Objects of a few micrometers up to a few tens of micrometers size can be trapped for extended periods of time. The selection and positioning of single objects out of a batch of many can be performed semi-automatically by software routines. The performance of the setup has been tested by wide-angle and small-angle X-ray scattering experiments on single optically trapped starch granules, using a synchrotron radiation microbeam. We demonstrate here for the first time the feasibility of microdiffraction on optically trapped protein crystals. Starch granules and insulin crystals were repeatedly raster-scanned at about 50 ms exposure/raster-point up to the complete loss of the structural order. Radiation damage in starch granules results in the appearance of low-angle scattering due to the breakdown of the polysaccharide matrix. For insulin crystals, order along the densely packed [110] direction is preferentially maintained until complete loss of long-range order. 相似文献
995.
Napp J Behnke T Fischer L Würth C Wottawa M Katschinski DM Alves F Resch-Genger U Schäferling M 《Analytical chemistry》2011,83(23):9039-9046
Polystyrene nanoparticles (PS-NPs) were doped with an oxygen-sensitive near-infrared (NIR)-emissive palladium meso-tetraphenylporphyrin and an inert reference dye which are both excitable at 635 nm. The nanosensors were characterized with special emphasis on fundamental parameters such as absolute photoluminescence quantum yield and fluorescence lifetime. The PS-NPs were employed for ratiometric dual-wavelength and lifetime-based photoluminescent oxygen sensing. They were efficiently taken up by cultured murine alveolar macrophages, yielding a characteristic and reversible change in ratiometric response with decreasing oxygen concentration. This correlated with the cellular hypoxic status verified by analysis of hypoxia inducible factor-1α (HIF-1α) accumulation. In addition, the surface of PS-NPs was functionalized with polyethylene glycol (PEG) and the monoclonal antibody herceptin, and their binding to HER2/neu-overexpressing tumor cells was confirmed in vitro. First experiments with tumor-bearing mouse revealed a distinctive ratiometric response within the tumor upon hypoxic condition induced by animal sacrifice. These results demonstrate the potential of these referenced NIR nanosensors for in vitro and in vivo imaging that present a new generation of optical probes for oncology. 相似文献
996.
Tschulik K Cierpka C Gebert A Schultz L Kähler CJ Uhlemann M 《Analytical chemistry》2011,83(9):3275-3281
A novel three-dimensional particle tracking velocimetry technique was used to examine the flow during electrodeposition of Cu. For the first time electrode-normal, circumferential, and radial velocities were spatially resolved during deposition in superimposed low and high magnetic gradient fields. In this way the complex interaction of magnetic field gradient force and Lorentz force induced convective effects could be measured and analyzed. Magnetic field gradient force induced electrolyte flow was detected only in high gradient magnetic fields, and it was found to be directed toward regions of gradient maxima. Since this electrode-normal flow causes enhanced transport of Cu(2+) ions from the bulk electrolyte to those regions of the working electrode where maxima of magnetic gradients are present, a structured deposit is formed during diffusion-limited electrodeposition. Lorentz force driven convection was observed during deposition in the low and the high magnetic gradient experiments. The overall fluid motion and the convection near the working electrode were determined experimentally and discussed with regard to the acting magnetic forces and numerical simulations. 相似文献
997.
One of the key challenges in reforming military fuels for use with fuel cells is their high sulfur content, which can poison the fuel cell anodes. Sulfur-tolerant fuel reformers can convert this sulfur into H(2)S and then use a desulfurizing bed to remove it prior to the fuel cell. In order to optimize and verify this desulfurization process, a gas-phase sulfur analyzer is required to measure H(2)S at low concentrations (<1 ppm(v)) in the presence of other reforming gases (e.g., 25-30% H(2), 10-15% H(2)O, 15% CO, 5% CO(2), 35-40% N(2), and trace amounts of light hydrocarbons). In this work, we utilize near-infrared cavity-enhanced optical absorption spectroscopy (off-axis ICOS) to quantify H(2)S in a JP-8 fuel reformer product stream. The sensor provides rapid (2 s), highly precise (±0.1 ppm(v)) measurements of H(2)S in reformate gases over a wide dynamic range (0-1000 ppm(v)) with a low detection limit (3σ = ±0.09 ppm(v) in 1 s) and minimal cross-interferences from other present species. It simultaneously quantifies CO(2) (±0.2%), CH(4) (±150 ppm(v)), C(2)H(4) (±30 ppm(v)), and H(2)O (±300 ppm(v)) in the reformed gas for a better characterization of the fuel reforming process. Other potential applications of this technology include measurement of coal syngas and H(2)S in natural gas. By including additional near-infrared, distributive feedback diode lasers, the instrument can also be extended to other reformate species, including CO and H(2). 相似文献
998.
Dana L. Morgan Gerry Triani Mark G. Blackford N. A. Raftery Ray L. Frost Eric R. Waclawik 《Journal of Materials Science》2011,46(2):548-557
In this study, the mechanism of precursor dissolution and the influence of kinetics of dissolution on titanate nanotube formation
were investigated. This comparative study explored the dissolution kinetics for the case of commercial titania powders, one
composed of predominantly anatase (>95%) and the other rutile phase (>93%). These nanoparticle precursors were hydrothermally
reacted in 9 mol L−1 NaOH at 160 °C over a range of reaction times of between 2 and 32 h. The high surface area nanotube-form product was confirmed
using X-ray diffraction, FT-Raman spectroscopy, and transmission electron microscopy. The concentration of nanotubes produced
from the different precursors was established using Rietveld analysis with internal and external corundum standardization
to calibrate the absolute concentrations of the samples. Interpretation of the dissolution process of the precursor materials
indicated that the dissolution of anatase proceeds via a zero-order kinetic process, whereas rutile dissolution is through
a second-order process. The TiO2 nanostructure formation process and mechanism of TiO2 precursor dissolution was confirmed by non-invasive dynamic light scattering measurements. Significant observations are that
nanotube formation occurred over a broad range of hydrothermal treatment conditions and was strongly influenced by the order
of precursor dissolution. 相似文献
999.
Kerstin Büchner Nadja Ehrhardt Brian P. Cahill Christian Hoffmann 《Thin solid films》2011,519(19):6480-6485
Internal reflection ellipsometry was used for detection of the consecutive coating of two polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA), onto a tantalum pentoxide (Ta2O5) substrate until the 10th bilayer. The UV patterned PAH-PAA-multilayer was characterized in air via ellipsometry and atomic force microscopy. Suited optical models enabled the determination of the layer thicknesses in wet and dry states. Linear multilayer formation could be proved by Attenuated Total Reflection — Fourier Transformed Infrared Spectroscopy measurements following the increase of the ν(C=O) band depending on the adsorption of the PAA. Streaming potential measurements after each layer deposition step indicated a change in surface charge after each layer deposition due to the consecutive coating of PAH and PAA. In this article the internal reflection ellipsometry is shown to be a convenient possibility to analyze the modification of a thin transparent Ta2O5 substrate. 相似文献
1000.