An oracle based method to compute a coupled equilibrium in a model of international climate policy

This paper proposes a computational game-theoretic model for the international negotiations that should take place at the end of the period covered by the Kyoto protocol. These negotiations could lead to a self-enforcing agreement on a burden sharing scheme given the necessary global emissions limit that will be imposed when the real extent of climate change is known. The model assumes a non-cooperative behavior of the parties except for the fact that they will be collectively committed to reach a target on total cumulative emissions by the year 2050. The concept of normalized equilibrium, introduced by J.B. Rosen for concave games with coupled constraints, is used to characterize a family of dynamic equilibrium solutions in an m-player game where the agents are (groups of) countries and the payoffs are the welfare gains obtained from a Computable General Equilibrium (CGE) model. The model deals with the uncertainty about climate sensitivity by computing an S-adapted equilibrium. These equilibria are computed using an oracle-based method permitting an implicit definition of the payoffs to the different players, obtained through simulations performed with the global CGE model GEMINI-E3. Partly supported by GICC (French Ministry of Ecology), TOCSIN (EU-044287) and the Swiss-NSF NCCR-Climate program of the Swiss NSF. For helpful comments and discussions, we thank A. Bernard, P. Thalmann, and the anonymous referee.     

无穷方差厚尾过程变点的小波估计

研究随机设计下噪声为厚尾随机变量时非参数函数中的变点估计问题.首先,通过设计变换将随机设计转化为等间距固定设计,进而利用小波方法估计变换后的变点的位置,再利用逆设计变换求得随机设计下变点位置的估计,并给出估计的收敛速度.模拟研究结果说明对于无穷方差厚尾过程中的变点估计问题小波方法是有效的.     

Characteristic responses of a semiconductor gas sensor depending on the frequency of a periodic temperature change

A novel gas-sensing system based on a dynamic nonlinear response is reported to enhance the selectivity toward sample gases using a single detector. A periodic temperature change was applied to a semiconductor gas sensor and the resulting conductance of the sensor was evaluated by fast Fourier transformation (FFT). The dynamic nonlinear response to the sample gases was further characterized depending on the frequency of the temperature change. The characteristic sensor response under the application of a temperature change was theoretically simulated by considering the kinetics of gas molecules on the semiconductor surface.     

壳管相变蓄热器强化传热实验研究

为了强化相变蓄热器传热性能,本文设计了三种新型壳管相变蓄热器结构,并对其换热性能进行实验研究。结果表明:在蓄热器内部添加分层结构和斜翅片换热性能最高,内部温度达到均匀化的时间随换热单元数增加而增大;换热管道间翅片的添加可有效地强化换热效果,改善蓄热器内部出现的温度严重分层现象,温度分布更加均匀;在研究范围内,换热流体温度的增加可有效提高蓄热器的换热效率,缩短相变时间。     

Shock waves in saturated thermoelastic porous media

The objective of this paper is to develop and present the macroscopic motion equations for the fluid and the solid matrix, in the case of a saturated porous medium, in the form of coupled, nonlinear wave equations for the fluid and solid velocities. The nonlinearity in the equations enables the generation of shock waves. The complete set of equations required for determining phase velocities in the case of a thermoelastic solid matrix, includes also the energy balance equation for the porous medium as a whole, as well as mass balance equations for the two phase. In the special case of a rigid solid matrix, the wave after an abrupt change in pressure propagates only through the fluid.     

铕(III)对伴清蛋白溶液构象的影响

用TNS疏水探针研究了脱铁伴清蛋白(apoOTf)和不同形式的铕伴清蛋白(Eu_N-OTf, Eu₂-OTf)的表面疏水暴露程度, 依次为apoOTf＞Eu_N-OTf＞Eu₂-OTf, 表明Eu^3＋与脱铁伴清蛋白N端结合引起蛋白构象变化大, 与C端结合引起蛋白构象变化小. 此外, 由盐酸胍对3种蛋白变性实验, 发现Eu^3＋与脱铁伴清蛋白的结合稳定了蛋白的结构, 稳定性依次为apoOTf＜Eu_N-OTf＜Eu₂-OTf. 离子强度效应也充分表明3种蛋白内部疏水基团相互作用依apoOTf＜Eu_N-OTf＜Eu₂-OTf顺序增大, 稳定性也依次增大. 本研究对进一步探讨Eu^3＋的生物效应提供理论依据.     

Biodegradation-induced surface change of polymer microspheres and its influence on cell growth

Biodegradable microspheres were fabricated by poly(?-caprolactone) (PCL) homopolymer and poly(?-caprolactone-b-ethylene oxide) (PCL-b-PEO) amphiphilic block copolymer. The regulation of microsphere surface morphology was successfully achieved by controlled enzymatic degradation. The morphological changes induced by biodegradation and their influences on the growth of MG-63 human osteosarcoma cells were studied. Results based on the evaluation of cytotoxicity and the morphological observation of MG-63 cells cultivated on microspheres showed better growth of cells on the surface of degraded microspheres than on the surface of those undegraded microspheres no matter they were fabricated by homopolymers or copolymers. The influences of morphological changes of microsphere surface before and after biodegradation on MG-63 cell growth were discussed. The results of this work indicated that the biodegradation-induced morphological changes of microspheres could be well controlled and were favorable for MG-63 cell attachment and proliferation.     

n-Hexane sorption in poly(ethylene-co-1-octene)s: Effect on phase composition and character

Diffusion of small-molecule penetrants in semi-crystalline polymers is retarded by two factors: penetrant detour bypassing impenetrable crystals and the constraining effect of the crystals on the amorphous component. Previous experiments have shown that the latter factor becomes much less important at higher penetrant concentration in the polymer. Structural changes in a series of poly(ethylene-co-1-octene)s occurring on saturation in n-hexane at 296 K, covering a wide range of crystallinity (17-75 wt.%), were studied by wide-angle X-ray scattering, Raman spectroscopy and NMR spectroscopy. Densification of the crystal unit cell and partial dissolution of the interfacial component on n-hexane sorption are the main experimental findings. The conclusion is that the penetrant molecules increase the mobility of the polymer chain segments adjacent to the crystal interface, enabling better packing of the crystal stems and importantly also causes a reduction in the constraining factor (β) for diffusion.     

Hydrogenation, structure and magnetic properties of La(Fe0.91Si0.09)13 hydrides and deuterides

Hydrogenation, crystal structure and magnetic properties of La(Fe0.91Si0.09)13H(D)y have been studied by pressure-composition isotherms (PCI), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and magnetization measurements. The maximum absorption capacity is found to be 1.9 H(D) atoms per formula unit as a solid solution. All hydrides and deuterides crystallize in the NaZn13-type cubic structure with the lattice parameter increasing linearly with H(D) concentration. The H(D) absorption enhances the Curie temperature significantly. The magnetic entropy change of the highly H-absorbed compound La(Fe0.91Si0.09)13H1.81 reaches ～26 J/kg·K under a magnetic field change of 5 T near the Curie temperature TC = 350 K. No observable isotope effect seems to imply that only the magnetovolume effect is responsible for the strong interplay between magnetism and lattice.     

Raman characterization of Pb2Na1−xLaxNb5−xFexO15 and Pb0.5(5−x)LaxNb5−xFexO15 (0≤x≤1) solid solutions

The ferroelectric compounds Pb₂Na_1−xLa_xNb_5−xFe_xO₁₅ and Pb_0.5(5−x)La_xNb_5−xFe_xO₁₅ (0≤x≤1) with the tungsten bronze type structure have been investigated using Raman spectroscopy. The evolution of the spectra as a function of composition at room temperature is reported. In the frequency range 200-1000 cm⁻¹ three main A₁ phonons around 240 (υ₁), 630 (υ₂) and 816 (υ₃) cm⁻¹ were observed. The broadening of the Raman lines for high values of x originates from a significant structural disorder. This is in good agreement with the relaxor character of these compositions. The lowest-frequency part of the spectra, below 180 cm⁻¹, reveals a structural change in the studied solid solutions. The behaviour of the Raman shift of the υ₁ mode confirms that in Pb₂Na_1−xLa_xNb_5−xFe_xO₁₅, a clear anomaly occurs in the vicinity of x=0.4.