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991.
There is concern that climate change may greatly increase the costs of providing water infrastructure in rich countries, but the estimates available cannot be compared across countries. This paper develops and applies a top-down approach to estimate the costs of adapting to climate change on a consistent basis for different climate scenarios. The analysis separates (a) the costs of maintaining service standards for a baseline projection of demand, and (b) the costs of changes in water use and infrastructure as a consequence of changes in climate patterns. The engineering estimates focus on the direct capital and operating costs of adaptation without relying upon economic incentives to affect patterns of water use. On this assumption, the costs of adaptation are 1–2% of baseline costs for all OECD countries with the main element being the extra cost of water resources to meet higher level of municipal water demand. There are large differences in the cost of adaptation across countries and regions. Adopting an economic approach under which water levies are used to cap total water abstractions leads to a large reduction in the burden of adaptation and generates savings of $6–12 billion per year under different climate scenarios. 相似文献
992.
993.
Alexander Kromka Lubica Grausova Lucie Bacakova Jiri Vacik Bohuslav Rezek Milan Vanecek Oliver A. Williams Ken Haenen 《Diamond and Related Materials》2010,19(2-3):190-195
The impact of boron doping level of nanocrystalline diamond (NCD) films on the character of cell growth (i.e., adhesion, proliferation and differentiation) is presented. Intrinsic and boron-doped NCD films were grown on Si/SiO2 substrates by microwave plasma CVD process. The boron-doped samples were grown by adding trimethylboron (TMB) to the gas mixture of methane and hydrogen. Highly resistive (0 ppm), semiconducting (133 or 1000 ppm), and metallic-like (6700 ppm) NCD films were tested as the artificial substrates for the cultivation of osteoblast-like MG 63 cells. The conductivity and surface charge increased monotonically with the increasing boron content. All NCD substrates showed good biocompatibility and stimulated the adhesion and growth of MG 63 cells. Higher osteocalcin concentration (by more than 30%) for the cells growing on 1000 and 6700 ppm boron-doped NCD films was found which indicates an enhancement in the cell growth biochemistry. 相似文献
994.
995.
Reaction of C60 fullerene with dialkyl bromomalonate (where the alkyl groups consist of short-, medium-, and long-saturated chains or unsaturated
long chains) in the presence of sodium hydride gives [6,6]-bridged mono-adducts of methanofullerene. The spectroscopic properties
of such fullerenoid lipids are reported. 相似文献
996.
Yuki Kojima Koji Inazu Yoshiharu Hisamatsu Hiroshi Okochi Toshihide Baba Toshio Nagoya 《Polycyclic Aromatic Compounds》2013,33(5):321-333
Atmospheric polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs and oxy-PAHs are emitted from primary sources. Some nitro-PAHs and oxy-PAHs can also arise from secondary formation in the atmosphere. To assess the relative importance of these sources, the polycyclic aromatic compound (PAC) concentrations were determined at a roadside (Roadside site) and on a rooftop (Urban Background site) in downtown Tokyo Japan. The concentrations of PAHs, 1-nitropyrene and oxy-PAHs at the Roadside site were higher than those at the Urban Background site, while 2-nitrofluoranthene levels were the same at both sites. However, the mean ratios of concentrations at the Urban Background site to the Roadside site were in the order 1,8-naphthalic anhydride>9,10-anthraquinone>PAHs or 1-nitropyrene or acenaphthenequinone or benzanthrone. This suggests that in addition to vehicle emissions, a considerable fraction of some of the oxy-PAHs studied originates from another source, which might be secondary formation by atmospheric PAH degradation, and this contribution varied among the oxy-PAHs. 相似文献
997.
998.
Max Gunzburger Eunjung Lee Yuki Saka Catalin Trenchea Xiaoming Wang 《Journal of scientific computing》2010,45(1-3):294-332
Fluid turbulence is commonly modeled by the Navier-Stokes equations with a large Reynolds number. However, direct numerical simulations are not possible in practice, so that turbulence modeling is introduced. We study artificial spectral viscosity models that render the simulation of turbulence tractable. We show that the models are well posed and have solutions that converge, in certain parameter limits, to solutions of the Navier-Stokes equations. We also show, using the mathematical analyses, how effective choices for the parameters appearing in the models can be made. Finally, we consider temporal discretizations of the models and investigate their stability. 相似文献
999.
1000.