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1.
Electric vehicles (EVs) are considered a promising alternative to conventional vehicles (CVs) to alleviate the oil crisis and reduce urban air pollution and carbon emissions. Consumers usually focus on the tangible cost when choosing an EV or CV but overlook the time cost for restricting purchase or driving and the environmental cost from gas emissions, falling to have a comprehensive understanding of the economic competitiveness of CVs and EVs. In this study, a life cycle cost model for vehicles is conducted to express traffic and environmental policies in monetary terms, which are called intangible cost and external cost, respectively. Battery electric vehicles (BEVs), fuel cell electric vehicles (FCEVs), and CVs are compared in four first-tier, four new first-tier, and 4 s-tier and below cities in China. The comparison shows that BEVs and FCEVs in most cities are incomparable with CVs in terms of tangible cost. However, the prominent traffic and environmental policies in first-tier cities, especially in Beijing and Shanghai, greatly increase the intangible and external costs of CVs, making consumers more inclined to purchase BEVs and FCEVs. The main policy benefits of BEVs and FCEVs come from three aspects: government subsidies, purchase and driving restrictions, and environmental taxes. With the predictable reduction in government subsidies, traffic and environmental policies present important factors influencing the competitiveness of BEVs and FCEVs. In first-tier cities, BEVs and FCEVs already have a competitive foundation for large-scale promotion. In new first-tier and second-tier and below cities, stricter traffic and environmental policies need to be formulated to offset the negative impact of the reduction in government subsidies on the competitiveness of BEVs and FCEVs. Additionally, a sensitivity analysis reveals that increasing the mileage and reducing fuel prices can significantly improve the competitiveness of BEVs and FCEVs, respectively.  相似文献   
2.
Independent hydrogen production from petrochemical wastewater containing mono-ethylene glycol (MEG) via anaerobic sequencing batch reactor (ASBR) was extensively assessed under psychrophilic conditions (15–25 °C). A lab-scale ASBR was operated at pH of 5.50, and different organic loading rates (OLR) of 1.00, 1.67, 2.67, and 4.00 gCOD/L/d. The hydrogen yield (HY) progressed from 134.32 ± 10.79 to 189.09 ± 22.35 mL/gMEGinitial at increasing OLR from 1.00 to 4.00 gCOD/L/d. The maximum hydrogen content of 47.44 ± 3.60% was achieved at OLR of 4.0 gCOD/L/d, while methane content remained low (17.76 ± 1.27% at OLR of 1.0 gCOD/L/d). Kinetic studies using four different mathematical models were conducted to describe the ASBR performance. Furthermore, two batch-mode experiments were performed to optimize the nitrogen supplementation as a nutrient (C/N ratio), and assess the impact of salinity (as gNaCl/L) on hydrogen production. HY substantially dropped from 62.77 ± 4.09 to 6.02 ± 0.39 mL/gMEGinitial when C/N ratio was increased from 28.5 to 114.0. Besides, the results revealed that salinity up to 10.0 gNaCl/L has a relatively low inhibitory impact on hydrogen production. Eventually, the cost/benefit analysis showed that environmental and energy recovery revenues from ASBR were optimized at OLR of 4.0 gCOD/L/d (payback period of 7.13 yrs).  相似文献   
3.
The visible light driven Bi2MoO6 photocatalyst doped with different contents of Ag nanoparticles was successfully synthesized by a combination of hydrothermal and sonochemical methods. The as-synthesized samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning and transmission electron microscopy (SEM and TEM) and UV–visible spectroscopy to investigate crystalline structure, morphology, composition and photocatalytic properties. XRD patterns and TEM images of the samples revealed pure phase orthorhombic Bi2MoO6 nanoplates without any detection of Ag dopant due to its low concentration and very tiny particle size. TEM images showed that Ag nanoparticles with the size of 10–15 nm were dispersed randomly on the surface of Bi2MoO6. The XPS analysis of Ag/Bi2MoO6 nanocomposites revealed the presence of additional metallic Ag. Photocatalytic activities of the Ag/Bi2MoO6 nanocomposites were evaluated by determining the degradation of rhodamine B (RhB) under visible light radiation. In this research, the 10 wt% Ag/Bi2MoO6 nanocomposites showed the best photocatalytic activity. The results suggest that the dispersion of Ag nanoparticles on the surface of Bi2MoO6 significantly enhances its photocatalytic activity.  相似文献   
4.
The transport sector's promotion of electric vehicles (EVs) is an important tool in reducing greenhouse gas emissions. The high monetary subsidies widely used to promote EV diffusion in many countries are not sustainable in the long term. Therefore, effective alternative incentives are needed as subsidies are gradually phased out. In this paper, consumers' willingness to pay (WTP) for alternative incentives is studied based on a questionnaire survey. Using a discrete choice experiment, 1719 Chinese consumer questionnaires were collected. Consumers' WTP for nine alternative policies was calculated by applying the multinomial logit model and mixed logit model, and the mixed logit model is used as the main model of this study because of its better statistical performance. Finally, the relationship between the respondent heterogeneity and policy preferences was studied. The results show that alternative incentives can fill the gap produced by subsidy reductions. EV privileges like no restrictions on driving and purchases, which have the lowest implementation cost, are suitable for first- and second- tier cities. For second-tier cities, construction of more charging stations is the most appropriate choice. The heterogeneous features of the respondents, including cities of residence, type of vehicle owned, recognition of the environmental benefits of EVs, gender, and whether the family has children, had a significant impact on policy preferences.  相似文献   
5.
以管道机器人(Pipeline inspection gauge,PIG)为载体的内检测技术是保障油气管道安全运输的重要手段。针对管内高压流体作用下,管道机器人在冲击管内环焊缝过程中产生的动力学行为突变问题。建立了管道周向受限空间中基于Kelvin弹簧阻尼的管道机器人密封盘等效动力学模型,结合管道机器人本体建立了多体系管道机器人动力学模型;详细推导了管道机器人轴向振动微分方程,以及管内流体的流动方程;并使用Matlab/Simulink与Adams进行流固耦合仿真,作为重要的工艺参数之一,研究了管道机器人速度改变时,其在冲击环焊缝过程中的动力学响应情况。结果表明:所建立的密封盘及管道机器人动力学模型能够很好地表征密封盘在管道轴向、径向以及周向的力学特性;运行速度越快,管道机器人通过环焊缝引起的轴向振动越剧烈,冲击振动越明显;而垂向和俯仰振动现象随运动速度增大而显著减弱。  相似文献   
6.
The demand for high-performance non-precious-metal electrocatalysts to replace the noble metal-based catalysts for oxygen reduction reaction(ORR)is intensively increasing.Herein,single-atomic copper sites supported on N-doped three-dimensional hierarchically porous carbon catalyst(Cu1/NC)was prepared by coordination pyrolysis strategy.Remarkably,the Cu1/NC-900 catalyst not only exhibits excellent ORR performance with a half-wave potential of 0.894 V(vs.RHE)in alkaline media,outperforming those of commercial Pt/C(0.851 V)and Cu nanoparticles anchored on N-doped porous carbon(CuNPs/NC-900),but also demonstrates high stability and methanol tolerance.Moreover,the Cu1/NC-900 based Zn-air battery exhibits higher power density,rechargeability and cyclic stability than the one based on Pt/C.Both experimental and theoretical investigations demonstrated that the excellent performance of the as-obtained Cu1/NC-900 could be attributed to the synergistic effect between copper coordinated by three N atoms active sites and the neighbouring carbon defect,resulting in elevated Cu d-band centers of Cu atoms and facilitating intermediate desorption for ORR process.This study may lead towards the development of highly efficient non-noble metal catalysts for applications in electrochemical energy conversion.  相似文献   
7.
8.
考察了双河油田双河联、江河联注入水堵塞地层的因素;膨胀性黏土,悬浮固体颗粒。细菌及悬浮污油。含膨胀性黏土的双河南、双河北及不含膨胀性黏土的双江岩心粉,在注入水中相对于地层水中的体积膨胀度分别为14.5%、11.1%及0.02%;注入100PV不含悬浮颗粒的等体积比地层水、注入水混合水使双河、双江岩心渗透率分别下降7%和4%、9%和7%。注入水中悬浮颗粒引起岩心渗透率下降,粒径越大、颗粒浓度越大、注入量越大,则渗透率越低。在粒径2.1μm或颗粒浓度3mg/L前后下降幅度变化较大。注入水中硫酸盐还原菌引起岩心渗透率下降,含菌量越大则渗透率开始下降时的注水量越小,注入含菌50个/L的水100PV使岩心渗透率下降7%。岩心对注水合油量敏感,注入含油量20mg/L的水50PV使岩心渗透率下降20%。在岩心注水实验中渗透率下降最严重的是双河南岩心,其次是双河北岩心.江河岩心较轻,注入精细过滤水的双河北岩心渗透率下降大大减少.说明悬浮固体是造成注水堵塞的主要因素。为了解除双河油田注水井的堵塞,研制了含黏土稳定剂、缓蚀剂、铁离子稳定剂、互溶剂的土酸液,与南阳油田使用的低伤害酸液一起,用于1口注水井的解堵,效果良好。图7表4参5。  相似文献   
9.
多孔陶瓷载体氧化铝涂层的研究   总被引:1,自引:1,他引:0  
分别用纳米γ-Al2O3和SB粉制备了多孔陶瓷载体的Al2O3涂层。BET法测定了多孔陶瓷载体Al2O3涂层改性前后比表面积的变化。由SEM照片观察多孔陶瓷载体涂层改性前后表面和断面的形貌。结果表明,这两种方法对多孔陶瓷载体涂层改性均有效可行。  相似文献   
10.
柴达木盆地断裂系统特征与油气勘探战略方向   总被引:3,自引:3,他引:0       下载免费PDF全文
基底断裂格局决定了盆地构造演化和沉积发育,导致了北缘、中部和昆北3个各具特色的断裂构造系统。北缘断裂构造系统平面上以反S展布、剖面上以一系列北倾南冲的逆冲断层带及其所控制的同沉积构造呈阶梯向南下掉为特点,受北部祁连山构造应力系统的作用;南部昆北断裂构造系统发育压陷断槽和断阶带,受南部昆仑山构造应力系统的作用;中部断裂构造系统以两断夹一隆的冲起构造为特色,同时受祁连山和昆仑山构造应力的共同作用。断裂对油气藏的形成和分布有重要的控制作用,表现在对烃源岩、储集条件、圈闭形成及油气运聚等方面。依据断裂控烃特征并针对柴达木盆地的具体情况,柴达木盆地油气勘探应迅速转移到盆地腹地即中部断裂构造系统区,尤其是鄂博梁Ⅱ号一伊克雅乌汝、鸭湖—台吉乃尔构造带和中南隆起区,有望取得重大突破。   相似文献   
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