Carbon dioxide emissions from port container distribution: Spatial characteristics and driving factors

Port carbon dioxide (CO₂) emissions in China have become an ever-increasing public concern due to their significant impacts on human health and the environment. However, existing studies focus mainly on CO₂ emissions from vessels calling at the ports and cargo handling within the ports, paying little attention to the inland distribution networks. To fill this gap, this paper proposes an easily implemented method for calculating CO₂ emissions from port container distribution (PCD) and investigates their spatial characteristics and driving factors. By analyzing 30 container ports in China, the main findings are as follows. First, road transportation is the major contributor of CO₂ emissions from PCD due to the lack of rail and inland water transportation. Second, PCD carbon emissions exhibit significant local spatial clustering. That is, ports with similar geographical locations tend to present a similar pattern of PCD carbon emissions. Third, as suggested by the spatial Durbin model, PCD carbon emissions are negatively determined by local gross domestic product, number of port berths, but are positively determined by local tertiary industry value and highway freight volume, and waterway freight volume in both local and neighboring ports. These results provide empirical insights into cross-port collaboration in reducing PCD carbon emissions.     

某新能源汽车复合材料前车门轻量化设计

本文以汽车前门作为研究对象,以碳纤维结构设计及铺层形式进行研究。经过仿真分析表明,碳纤维前车门的模态、刚度、强度都得到了明显的提升,在满足性能要求的基础上,重量得到了减轻,实现了轻量化的目的。     

基于碳中和目标下公路建设的经验观察与分析

本文从低碳环保理念出发,首先提出了基于碳中和目标下的公路工程建设的理念,通过绿色公路的低碳建设对其进行诠释,从公路建设的不同阶段分析了低碳公路建设的要点,并针对目前进行低碳建设所面临的一些难题,提出了几点解决措施,从而大幅度降低公路建设过程中的碳排放,实现碳中和目标下的交通强国建设。     

耦合不同车辆类型的城市道路交通全生命周期评价研究

城市道路交通是我国节能减碳重要领域,如何量化集成道路和车辆的城市道路交通的能源消耗和碳排放成为交通绿色发展的迫切需求。利用全生命周期评价方法,量化评价了城市道路交通原材料获取、施工制造、运行维护和报废拆除阶段的全生命周期化石能源消耗量ADP(f)和全球变暖潜值GWP (以CO₂当量计),讨论对比了基于传统燃油汽车(ICEV)、混合动力汽车(HEV)、插电式混合动力汽车(PHEV)、纯电动汽车(BEV)和燃料电池汽车(FCV)的城市道路交通的全生命周期ADP(f)和GWP,并对关键因素年均日通行量、FCV的技术进步和不同车型占比进行了敏感性分析。研究发现,基于ICEV的城市道路交通的全生命周期ADP(f)和GWP分别为3.26E+09 MJ和2.16E+08 kg。相比于ICEV,基于BEV的城市道路交通的全生命周期ADP(f)和GWP分别降低32.5%和36.1%。     

面向碳中和的汽车行业碳排放核算

汽车行业是我国交通领域碳排放的重点行业。在应对气候变化、实现碳达峰碳中和的形势下,制定适合我国汽车行业现状并引领汽车行业绿色发展的碳排放核算体系刻不容缓。在总结国内外碳排放核算工作研究进展的基础上,从企业/组织层面、产品层面和项目/服务层面阐述了汽车行业碳排放核算范围与用途。提出了从生命周期角度开展我国汽车行业碳排放核算的工作方法与思路,指出了核算过程中有关核算边界确定、数据收集与数据质量评估以及清单结果计算中的关键要点。从碳排放核算标准建立、基础数据库建设、低碳产品标识制度完善等方面给出了汽车行业开展碳排放核算工作的建议。建立并完善汽车行业的碳排放核算体系,不仅有利于摸清汽车企业的碳排放家底,帮助汽车企业识别碳排放关键环节,还可促进汽车行业上下游全产业链的协同减碳,从而推动我国汽车、交通、能源行业的健康可持续发展。     

装配式空心钢管混凝土支撑技术研究及应用

在“双碳”战略背景下提出一种新型装配式空心钢管混凝土支撑。为了研究其受力性能并将其应用于地下车站深基坑工程中,设计并加工2个足尺寸空心钢管混凝土支撑试件,完成轴压加载试验,2个支撑试件最后均发生了混凝土压碎破坏,同时得到试件承载力指标。采用ABAQUS有限元软件建立空心钢管混凝土支撑的数值模型,开展考虑材料非线性和几何非线性的有限元分析,所得数值分析结果与试验结果吻合良好,验证了有限元模型的准确性。试验和有限元结果充分表明所提出的新型装配式空心钢管混凝土支撑满足常规工程设计要求,已成功应用于“汤马区间”2号风井工程,并与现浇钢筋混凝土支撑和装配式钢管支撑进行比较分析,结果表明该新型支撑可以显著降低碳排放量和经济成本。     

漳州市中心城区内河水系水环境改善技术研究

在城市更新及双碳背景下,老城区水环境的改善与提升是目前各城市亟待解决的难题。以漳州市中心城区内河水系水环境治理为例,从河流生态系统的角度结合模型分析论述水体污染的根本原因和实质,提出改善水环境与提升水生态功能的方案建议,为项目的实施提供科学依据,也为城市整体水环境的提升提供参考。通过技术方案的应用与实施,使得水污染得到有效控制,黑臭水体得到治理,改善水环境,修复流域生态属性,助力减污降碳协同增效的实施,带来良好的生态环境及经济效益。     

Microbial community structure in the marginal ice zone of the Bellingshausen Sea

Phytoplankton, bacteria and microzooplankton were investigated on a transect in the Bellingshausen Sea during the ice melt period in November–December 1992. The transect along the 85°W meridian comprised seven stations that progressed from solid pack-ice (70°S), through melting ice into open water (67°S). The abundance, biomass and taxonomic composition were determined for each component of the microbial community. The phytoplankton was mostly dominated by diatoms, particularly small (<20 μm) species. Diatom abundance ranged from 66 000 cells l⁻¹ under the ice to 410 000 cells l⁻¹ in open water. Phytoplankton biomass varied from <1 to 167 mg C m⁻³, with diatoms comprising 89–95% of the total biomass in open water and autotrophic nanoflagellates comprising 57% under the ice. The standing stocks of autotrophs in the mixed layer ranged from 95 mg C m⁻² under the pack-ice to 9478 mg C m⁻² in open waters. Bacterial abundance in ice-covered and open water stations varied from 1.1 to 5.5×10⁸ cells l⁻¹. Bacterial biomass ranged from 2.4 mg C m⁻³ under pack-ice to an average of 14 mg C m⁻³ in open water. The microzooplankton consisted mainly of aloricate oligotrich ciliates and heterotrophic dinoflagellates and these were most abundant in open waters. Their biomass varied between 0.2 and 54 mg C m⁻³ with a minimum at depth under the ice and maximum in open surface waters. Microheterotrophic standing stocks varied between 396 mg C m⁻² under pack-ice and 3677 mg C m⁻² in the open waters. The standing stocks of the total microbial community increased consistently from 491 mg C m⁻² at the ice station to 13 155 mg C m⁻² in open waters, reflecting the productive response of the community to ice-melt. The composition of the microbial community also shifted markedly from one dominated by heterotrophs (82% of microbial stocks) at the ice station to one dominated by autotrophs (73% of microbial stocks) in the open water. Our estimates suggest that the microbial community comprised >100% of the total particulate organic carbon (POC) under the ice and 62–66% of the measured POC in the open waters.     

广州地铁一号线车辆的磨耗情况分析

通过对广州地铁一号线车辆运行中闸瓦、车轮及受电弓碳滑板的磨损量分析，确认广州地铁一号线车辆选用交流传动、轮轨参数及弓网参数等关键技术的正确和合理性及由此获得的良好性能。     

基于文物热安全度的文物保护环境控制研究

合理有效地控制文物保存环境是文物保护最基本和最重要的工作。规范里对文物保护环境的温度控制仅从环境温度方面着手,而该参数并不能真正反映文物的温度状态,以此为文物保护环境控制的依据存在缺陷,基于此,本文提出了一个全新的概念——文物热安全度,它综合了温度、湿度、风速和辐射四个指标对文物温度的影响。结合北京市某博物馆的文物展厅,对其四项指标进行了三次测试实验,结果表明:环境温度与文物本身的温度的确存有差异。将文物热安全度应用于博物馆智能空调系统,可对文物保护环境进行高精度的控制,还可保证空调系统的低碳节能运行,具有较高的社会、经济效益,值得在博物馆设计中推广应用。