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41.
简单介绍了碳纤维布加固钢筋混凝土梁的新方法,并论述了其发展状况和技术优势.  相似文献   
42.
分析了潜艇舱室固态胺CO_2吸附及水蒸汽再生的反应机理,指出了CO_2水合反应和水合CO_2分解反应分别为吸附与再生过程的慢反应。在实际工况下,固态胺吸附CO_2的速率受传质控制,水蒸汽再生过程很快,其速率不是主要关注的问题。基于双膜理论及双电层理论,分析讨论了固态胺吸附传质过程,推导出了CO_2总的传质速率方程,给出了影响速率的两个可调因素--温度及固态胺的含水量。  相似文献   
43.
白灵菇是一种营养丰富的食用菌,目前在国内市场供不应求,而在其反季节种植过程中,存在着冷库内CO2浓度逐步升高,影响产量和形状的问题。为解决这些问题,介绍了新研制的一种新型的CO2脱除机,可以较好的控制反季种植中冷库内的CO2浓度。测试了冷库内不同生长阶段白灵菇产生的CO2浓度,考察了冷库内不同高度时的CO2浓度的梯度变化,以及在试验中后期冷库内CO2浓度的变化速度。提出了白灵菇反季节种植冷库中CO2脱除机的运行方式。  相似文献   
44.
以混合的金属氧化物RuO_2、TiO_2、Ag_2O和SnO_2对钛表面进行了修饰,得到了四个不同氧化物组成的钛电极,即RuO_2 TiO_2/Ti(35:65,A)、RuO_2 TiO_2/Ti(25:75,B)、RuO_2 TiO_2 Ag_2O/Ti(C)和RuO_2 TiO_2 SnO2/Ti(D),采用循环伏安法研究了其常温常压下在0.1mol/L的KHCO3水溶液中的电化学行为,在-900mV的恒定电位下进行了CO2的还原,分析了电极的稳定性和还原产物的情况。结果表明,金属氧化物电极对CO2还原产生了很好的催化作用,-900mV下对甲酸和甲醇有高的选择性,还原的液相产物中仅发现了甲酸和甲醇,电极A、B、C和D上生成甲酸和甲醇的总电流效率分别为84.4%、57.4%、93.1%和88.1%,且长时间电解过程中电极具有很好的稳定性,是有很好应用前景的催化电极材料。  相似文献   
45.
模拟核潜艇环境工况条件,对固态胺纤维吸附CO2进行研究。实验测定了环境温度25℃、环境压力101kPa、气相中CO2含量0.5%时,固态胺纤维有水存在下吸附CO2的速率为5.57×10-4mmolig-1is-1。理论分析了吸附速率的控制过程,结果表明固态胺纤维吸附CO2总速率受双膜理论的液膜控制。  相似文献   
46.
Atmospheric molar fraction of CO2 (xCO2atm) measurements obtained on board of ships of opportunity are used to parameterize the seasonal cycle of atmospheric xCO2 (xCO2atm) in three regions of the eastern North Atlantic (Galician and French offshore and Bay of Biscay). Three selection criteria are established to eliminate spurious values and identify xCO2atm data representative of atmospheric background values. The filtered data set is fitted to seasonal curve, consisting of an annual trend plus a seasonal cycle. Although the fitted curves are consistent with the seasonal evolution of xCO2atm data series from land meteorological stations, only ship-board measurements can report the presence of winter xCO2atm minimum on Bay of Biscay. Weekly air–sea CO2 flux differences (mmol C·m− 2 day− 1) produced by the several options of xCO2atm usually used (ship-board measurements, data from land meteorological stations and annually averaged values) were calculated in Bay of Biscay throughout 2003. Flux error using fitted seasonal curve relative to on board measurements was minimal, whereas land stations and annual means yielded random (− 0.2 ± 0.3 mmol C·m− 2·day− 1) and systematic (− 0.1 ± 0.4 mmol C·m− 2 day− 1), respectively. The effect of different available sources of sea level pressure, wind speed and transfer velocity were also evaluated. Wind speed and transfer velocity parameters are found as the most critical choice in the estimate of CO2 fluxes reaching a flux uncertainty of 7 mmol C·m− 2·day− 1 during springtime. The atmospheric pressure shows a notable relative effect during summertime although its influence is quantitatively slight on annual scale (0.3 ± 0.2 mmol C·m− 2·day− 1). All results confirms the role of the Bay of Biscay as CO2 sink for the 2003 with an annual mean CO2 flux around − 5 ± 5 mmol C m− 2 day− 1.  相似文献   
47.
Air–sea fluxes in the Caribbean Sea are presented based on measurements of partial pressure of CO2 in surface seawater, pCO2sw, from an automated system onboard the cruise ship Explorer of the Seas for 2002 through 2004. The pCO2sw values are used to develop algorithms of pCO2sw based on sea surface temperature (SST) and position. The algorithms are applied to assimilated SST data and remotely sensed winds on a 1° by 1° grid to estimate the fluxes on weekly timescales in the region. The positive relationship between pCO2sw and SST is lower than the isochemical trend suggesting counteracting effects from biological processes. The relationship varies systematically with location with a stronger dependence further south. Furthermore, the southern area shows significantly lower pCO2sw in the fall compared to the spring at the same SST, which is attributed to differences in salinity. The annual algorithms for the entire region show a slight trend between 2002 and 2004 suggesting an increase of pCO2sw over time. This is in accord with the increasing pCO2sw due the invasion of anthropogenic CO2. The annual fluxes of CO2 yield a net invasion of CO2 to the ocean that ranges from − 0.04 to − 1.2 mol m− 2 year− 1 over the 3 years. There is a seasonal reversal in the direction of the flux with CO2 entering into the ocean during the winter and an evasion during the summer. Year-to-year differences in flux are primarily caused by temperature anomalies in the late winter and spring period resulting in changes in invasion during these seasons. An analysis of pCO2sw before and after hurricane Frances (September 4–6, 2004), and wind records during the storm suggest a large local enhancement of the flux but minimal influence on annual fluxes in the region.  相似文献   
48.
潜艇舱室固态胺CO2清除技术的化学热力学分析   总被引:2,自引:0,他引:2  
依据有关文献提供的热力学状态函数值,分水蒸汽再生和真空再生两种工况,近似计算了标准状态和实际状况下固态胺吸附与解吸CO2反应的平衡与程度,并讨论了温度、湿度和二氧化碳分压等对其所产生的影响。  相似文献   
49.
The Arctic route has huge potential for shipping between Europe and Northeast Asia with significant savings in transit time and distance. However, GHG emissions from shipping would harm the environment of Arctic area. Potential Market Based Measures of GHG emission reduction (such as carbon tax) are under consideration but they may affect the economic viability of Northern Sea Route (NSR) for containerships. This paper investigates the economic viability of NSR against Suez Canal Route (SCR) under 2 proposed carbon tax schemes (fixed vs. progressive). Three different fuel oil types (Heavy Fuel Oil, Light Fuel Oil, Liquified Natural Gas) are used as main bunker fuel for the calculation of economic feasibility. Our result reveals that when there is no carbon tax on NSR nor SCR, or both routes are under a carbon tax scheme, no matter fixed or progressive, NSR is more economically viable, regardless of fuel type choice. When only NSR is under a carbon tax scheme, the viability depends on specific carbon tax scheme and fuel choice, but for the majority of containership sizes, NSR has lower unit cost. The result also suggests that for a given route, a progressive scheme in preferable than a fixed one and LNG would be an appealing fuel with lower unit cost.  相似文献   
50.
    
Nowadays, sustainability issues have received considerable attention in supply chain management because of the governmental requirements as well as expectations of the people. This paper introduces a novel supply chain network design problem to cover three dimensions of sustainability, namely economic, environmental, and social. The advantage of the presented model stems from considering the booming development aligned with reduction in environmental impact. In this paper, to achieve the mentioned benefits and to derive a more sustainable supply chain, a novel model in the presence of the most commonly used carbon policies is proposed. This paper, addresses sustainable development through imposing proper carbon regulatory mechanisms. Main contribution of this study is to consider the effect of imposing carbon policies on environmental advantages as well as improving the regional development level in a supply chain network design problem. Moreover, the shipment consolidation decisions are utilized to reduce cost as well as environmental impact. In addition, a novel mixed uncertainty approach is proposed to capture the uncertain emission parameters. The numerical examples and a case study are analyzed to evaluate the performance of the proposed models. It is concluded that, a high-growth economy with low-carbon can be made and also almost global well-being of people is ensured by applying the proposed model. Some managerial insights are provided for the enterprises of supply chains to make the most appropriate sustainable decisions. Finally, proper carbon emission policies are suggested based on the region sustainability characteristics.  相似文献   
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