Economics of climate policy and collective decision making

This paper explores the reasons why economic instruments of climate change are reluctantly applied and stresses the need for interdisciplinary research linking economic theory and empirical testing to deliberative political procedures. It is divided in three parts. The first one recalls the main issues in implementing Cost-Benefit Analysis such as information problems, uncertainties, discounting the future and irreversibilities. The second part shows how these issues can be treated in integrated assessment and techno-economic models and presents a case study, which shows that

• The chosen scenario tends to stabilize atmospheric CO₂ concentration at around 550 ppm in the long run.
• Exclusion of possibility to trade CO₂ emission permits under a cap regime would increase the cost of emission abatement for OECD countries.
• Combining different flexibility instruments might lead to significant gains in the overall cost of climate policy.

The third part presents results of a survey conducted among the main economic and environmental associations in Switzerland. The survey reveals conflicting views on economic instruments. It shows how the social acceptability of these instruments can be improved in taking explicitly into account these opposing views of special interest groups. Therefore, policy scenarios should be selected in combining techno-economic models with empirical studies about their political and normative context.     

广东地区地震动衰减和场地响应的研究

根据广东数字地震台网14个地震台的249条波形资料，研究了广东地区的衰减模型和各台站的场地响应. 采用三段几何衰减模型拟合，得到了广东地区的几何衰减函数. 同时也采用线性几何衰减模型和两段几何衰减模型对观测数据进行了拟合. 残差比较表明，线性几何衰减模型的残差最大，两段几何衰减模型的残差其次，而三段几何衰减模型的残差最小. 由此可以推论广东地区采用三段几何衰减模型具合理性和适用性. 得到广东地区非弹性衰减Q值随频率f的关系为Q(f)=481.5·f0.31；14个台站的场地响应均没有显示出明显的放大效应，这与它们均处于岩石地基相符.     

膨胀土地基中隧道施工对群桩影响研究

在膨胀土地基中进行隧道对群桩影响的三维离心模型试验研究,目标地层损失比为2%,着重研究引起的地基沉降槽、桩的附加沉降、附加弯矩、轴力的变化规律。试验得出：隧道开挖沉降槽空间效应明显;隧道开挖从-0.75D至1.25D时,桩附加沉降呈线性增长,隧道开挖至1.25D以后,桩依然沉降明显。前桩与后桩沉降值不同,桩帽会出现倾斜;前桩上部出现负附加弯矩而下部出现正附加弯矩,而后桩仅在下部出现正附加弯矩;前桩附加弯矩最大值出现在隧道轴线附近,且比后桩附加弯矩大得多;前桩附加轴力随着隧道的开挖而增加,且每步最大值在隧道轴线附近。后桩的轴力也随隧道的开挖而增加,但每步最大值出现在桩顶附近。     

Stabilization of Fe/Cu nanoparticles by starch and efficiency of arsenic adsorption from aqueous solutions

Due to the severity of arsenic contamination of soil and water resources around the world, finding new adsorbents for arsenic removal from the water is of high importance. The present study investigates the possible use and effectiveness of starch-stabilized Fe/Cu nanoparticles for adsorption of arsenic from aqueous solutions. First, Fe/Cu nanoparticles at various starch concentrations of 0, 0.02, 0.04 and 0.06 wt% were synthesized and characterized by X-ray diffraction, transmission electron microscopy and zeta potential/particle size analyzer. Then 0.04 wt% stabilized Fe/Cu nanoparticles were tested for the sorption of As(III) and As(V) from synthetic arsenic-contaminated water. To have an understanding about the arsenic adsorption mechanism of nanoparticles, X-ray photoelectron spectroscopy (XPS) was performed before and after adsorption. The results showed that starch provides nanoparticles with a neutral surface and stabilization of nanoparticles is possible with 0.04 wt% or higher concentrations of starch. For 0.04 wt% starch-stabilized Fe/Cu nanoparticles, the adsorption isotherms fit well within the Langmuir equation, with maximum sorption capacities of 90.1 mg/g for As(III) and 126.58 mg/g for As(V) at a pH of 7.0 from the aqueous arsenic solutions. Examining the XPS spectra of nanoparticles before and after adsorption showed that arsenic adsorption by this nanoparticle can be due to the formation of inner-sphere arsenic complexes on the particle surface, and the surface oxygen-containing functional groups involved in adsorption. The high sorption capacity suggests the potential for applying starch-stabilized Fe/Cu nanoparticles to the contaminated waters for removal of arsenic.     

The First Stegosaur （Dinosauria, Ornithischia） from the Upper Jurassic Shishugou Formation of Xinjiang, China

A new stegosaur species, Jiangjunosaurus junggarensis, gen. et sp. nov., is erected based on a specimen collected from the Upper Jurassic upper section of the Shishugou Formation in the Junggar Basin, Xinjiang, China. It represents the first stegosaur from the Jurassic of Xinjiang and increases the diversity of the dinosaur fauna in the Shishugou Formation. The new genus is characterized by symmetrical and proportionally wide tooth crowns, a sub-rectangular axial neural spine seen in lateral view, and large openings on the lateral surfaces of the cervical centra. A preliminary character analysis suggests that this new taxon is more derived than the Middle Jurassic stegosaur Huayangosaurus but more primitive than most other known stegosaur species.     

Numerical models of ionic diffusion in one and three dimensions: application to dehydration of mantle olivine

The hydrogen content of nominally anhydrous minerals is of great interest, because it can influence many physical and mechanical properties of mantle rocks. Moreover, the hydrogen diffusion profiles can be used to constrain timescales related to magma eruptions. Here, we report models of ionic diffusion for trace elements in anisotropic crystals and apply them to hydrogen diffusing out of mantle-derived olivine. We first compare and discuss the characteristics of 1D and 3D models and show that only 3D anisotropic diffusion models can lead to diffusion profiles exhibiting non-equilibrium plateau at the center of the solid along the slowest axis, as measured in natural samples. In a second part, we discuss the differences between hydration and dehydration of olivine for diffusion that is linked to two different atomic sites involved in hydrogen mobility. Finally, we apply our 3D anisotropic model to previous results on mantle-derived olivine from Pali-aike to better characterize diffusion coefficients and their anisotropy that could be relevant for dehydration of olivine. Our results show that dehydration has to be strongly anisotropic, with a fast [100] axis and a significantly slower [001] axis.