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81.
Adriaan Perrels 《Energy Efficiency》2010,3(2):149-165
In most countries with greenhouse gas emission reduction commitments, transportation has been relatively spared, thus, far
in the targeting of reduction obligations, owing to the supposedly high marginal cost. With the prospect of tightening reduction
targets, pressure is, however, mounting to address transportation more seriously in the near term and not to rely solely on
medium to long-term breakthroughs of alternative fuel technologies. This means stricter policies at the demand side of the
mobility market. In addition to fiscal and spatial policies, cap-and-trade systems have been put forward as a new option that
deserves serious consideration. This paper reviews the possibilities and pitfalls of such a system applied to passenger transport.
Key concerns are the transaction costs of the system and trade-offs between transaction cost and equity effects. A simple
system with low(er) transaction cost is more likely to invoke politically sensitive equity effects. On the basis of the recent
upsurge in monitoring and feedback studies, one may also conclude that the organisation and tailoring of the information interfaces
for the household/traveller requires still elaborate study and testing. 相似文献
82.
Maleic anhydride grafted polypropylene (MAPP) was blended with ethylene–vinyl acetate (EVA) copolymer to form MAPP/EVA polymer blends. Wood powder (WP) was mixed into these blends at different weight fractions to form MAPP/EVA/WP blend composites. Differential scanning calorimetry (DSC) analysis of the blends showed small melting peaks between those of EVA and MAPP, which indicated interaction and cocrystallization of fractions of EVA and MAPP. The presence of MAPP influenced the EVA crystallization behavior, whereas the MAPP crystallization was not affected by the presence of EVA. Scanning electron microscopy, Fourier transform infrared spectroscopy, and DSC results show that the WP particles in the MAPP/EVA blend were in contact with both the MAPP and EVA phases and that there seemed to be chemical interaction between the different functional groups. This influenced the crystallization behavior, especially of the MAPP phase. The thermogravimetric analysis results show that the MAPP/EVA blend had two degradation steps. An increase in the WP content in the blend composite led to an increase in the onset of the second degradation step but a decrease in onset of the first degradation step. The presence of WP in the blend led to an increase in the modulus but had almost no influence on the tensile strength of the blend. The dynamic mechanical analysis results confirm the interaction between EVA and MAPP and show that the presence of WP only slightly influenced the dynamic mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
83.
84.
纤维缠绕环形容器可充分利用空间,节省结构质量和消除系统质心漂移,目前在很多工业领域中发挥着日益重要的作用。本文基于复合材料层合理论和测地线缠绕原理,提出了纤维缠绕环形压力容器的线型优化设计方法。应用微分几何,导出了圆环面上测地缠绕轨迹和纤维不架空判据。以初始缠绕角和缠绕层厚度为变量,对结构重量进行最小化设计,得到了对应于不同管径比的优化缠绕线型。对优化线型进行了计算机缠绕仿真,并给出了缠绕铺层的各向正轴应力分布。结果表明,优化设计的缠绕线型模式精确可靠,满足纤维缠绕的基本要求。纤维缠绕角度大小更趋于合理,从而能充分发挥缠绕结构的力学性能,减经系统重量,使优化得到的环形容器结构性能比传统测地线缠绕环形容器有很大提高。本文的设计计算方法可直接用于复合材料环形气瓶的初步设计。 相似文献
85.
van Honk Jack; Tuiten Adriaan; Hermans Erno; Putnam Peter; Koppeschaar Hans; Thijssen Jos; Verbaten Rien; van Doornen Lorenz 《Canadian Metallurgical Quarterly》2001,115(1):238
Recently, it was demonstrated how individuals with high levels of testosterone selectively attend toward angry faces. It was argued that this suggests that high levels of testosterone are associated with an aggressive, dominating personality style. In this study, the authors used a double-blind, placebo-controlled design to examine whether exogenous testosterone would induce cardiac acceleration in response to angry faces. Participants (healthy young women) were exposed to neutral, happy, or angry faces. Administration of a single dosage of testosterone (0.5 mg) induced an accelerative cardiac response to angry faces. It is argued that this effect is due to the encouragement of dominance behavior and the inclination toward aggression. Possible mechanisms behind testosterone-driven changes in behavior are discussed with relevance to steroid-responsive networks in the limbic system that drive and control motivational and physiological aspects of social behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
87.
Maria Eleni Ourailidou Jan‐Ytzen van der Meer Bert‐Jan Baas Margot Jeronimus‐Stratingh Dr. Aditya L. Gottumukkala Prof. Dr. Gerrit J. Poelarends Prof. Dr. Adriaan J. Minnaard Prof. Dr. Frank J. Dekker 《Chembiochem : a European journal of chemical biology》2014,15(2):209-212
An increasing number of chemical reactions are being employed for bio‐orthogonal ligation of detection labels to protein‐bound functional groups. Several of these strategies, however, are limited in their application to pure proteins and are ineffective in complex biological samples such as cell lysates. Here we present the palladium‐catalyzed oxidative Heck reaction as a new and robust bio‐orthogonal strategy for linking functionalized arylboronic acids to protein‐bound alkenes in high yields and with excellent chemoselectivity even in the presence of complex protein mixtures from living cells. Advantageously, this reaction proceeds under aerobic conditions, whereas most other metal‐catalyzed reactions require inert atmosphere. 相似文献
88.
Adriaan Stephanus Luyt Ana Antunes Anton Popelka Abdelrahman Mahmoud Mohammad Korany Hassan Peter Kasak 《应用聚合物科学杂志》2021,138(43):51266
The effect of accelerated weathering degradation on the properties of poly(lactic acid) (PLA)/poly(ε-caprolactone) (PCL) blends and PLA/PCL/titanium (IV) dioxide (TiO2) nanocomposites are presented in this paper. The results show that both polymers are susceptible to weathering degradation, but their degradation rates are different and are also influenced by the presence of TiO2 in the samples. Visual, microscopic and atomic force microsocpy observations of the surface after accelerated weathering tests confirmed that degradation occurred faster in the PLA/PCL blends than in the PLA/PCL/TiO2 nanocomposites. The X-ray diffraction results showed the degradation of PCL in the disappearance of its characteristic peaks over weathering time, and also confirmed that PLA lost its amorphous character and developed crystals from the shorter chains formed as a result of degradative chain scission. It was further observed that the presence of TiO2 retarded the degradation of both PLA and PCL. These results were supported by the differential scanning calorimetry results. The thermogravimetric analysis results confirmed that that PLA and PCL respectively influenced each other's thermal degradation, and that TiO2 played a role in the thermal degradation of both PLA and PCL. The tensile properties of both PLA/PCL and PLA/PCL/TiO2 were significantly reduced through weathering exposure and the incorporation of TiO2. 相似文献
89.
Priego EM Pérez-Pérez MJ von Frijtag Drabbe Kuenzel JK de Vries H Ijzerman AP Camarasa MJ Martín-Santamaría S 《ChemMedChem》2008,3(1):111-119
Based on our previous results on the potent antagonist effect of 1H,3H-pyrido[2,1-f]purine-2,4-diones at the human A(3) adenosine receptor, new series of this family of compounds have been synthesized and evaluated in radioligand binding studies against the human A(1), A(2A), A(2B), and A(3) receptors. A remarkable improvement in potency, and most noticeable, in selectivity has been achieved, as exemplified by the 3-cyclopropylmethyl-8-methoxy-1-(4-methylbenzyl)-1H,3H-pyrido[2,1-f]purine-2,4-dione (10) that combines a very high affinity at hA(3) (K(i)=2.24 nM), with lack of affinity for the A(1), A(2A), and A(2B) receptors. On the basis of the published hA(3) receptor model (PDB 1OEA), molecular modeling studies, including molecular dynamics (MD) simulations, have been performed to depict the binding mode of the 1 H,3H-pyrido[2,1-f]purine-2,4-diones and to justify the selectivity against the other adenosine receptors. These studies have led to novel features of the cavity where our antagonists are bound so that the cavity is lined by the hydrogen-bonded Gln 167-Asn 250 pair and by the highly conserved Phe 168. 相似文献
90.
Lemay M Vesin JM van Oosterom A Jacquemet V Kappenberger L 《IEEE transactions on bio-medical engineering》2007,54(3):542-546
Due to the much higher amplitude of the electrical activity of the ventricles in the surface electrocardiogram (ECG), its cancellation is crucial for the analysis and characterization of atrial fibrillation. In this paper, two different methods are proposed for this cancellation. The first one is an average beat subtraction type of method. Two sets of templates are created: one set for the ventricular depolarization waves and one for the ventricular repolarization waves. Next, spatial optimization (rotation and amplitude scaling) is applied to the QRS templates. The second method is a single beat method that cancels the ventricular involvement in each cardiac cycle in an independent manner. The estimation and cancellation of the ventricular repolarization is based on the concept of dominant T and U waves. Subsequently, the atrial activities during the ventricular depolarization intervals are estimated by a weighted sum of sinusoids observed in the cleaned up segments. ECG signals generated by a biophysical model as well as clinical ECG signals are used to evaluate the performance of the proposed methods in comparison to two standard ABS-based methods. 相似文献