hydrogen

氢气
  • 文章类型: Journal Article
    这项研究介绍了一种氢传感器,该传感器由使用称为射频共溅射(RF共溅射)的技术沉积的氧化镁锌(MgZnO)薄膜制成。分别使用氧化镁(MgO)和氧化锌(ZnO)靶来沉积MgZnO薄膜,试验不同的沉积时间和功率水平。当暴露于浓度为百万分之1000(ppm)的氢气时,传感器表现最佳(达到2.46的感测响应)。在300°C的温度下,当MgZnO膜厚度为432纳米(nm)时,出现了该峰值性能。最初,传感器的响应性随着薄膜厚度的增加而增加。这是因为较厚的薄膜倾向于具有更多的氧空位,这些是在传感器功能中起作用的缺陷。然而,膜厚度进一步增加超过最佳点损害性能。这归因于薄膜内晶粒的生长,这阻碍了它的有效性。使用X射线衍射(XRD)和场发射扫描电子显微镜(FE-SEM)对MgZnO薄膜的质量进行了全面表征。这些技术为薄膜的晶体结构和形态提供了有价值的见解,影响其作为氢传感器性能的关键因素。
    This research introduces a hydrogen sensor made from a thin film of magnesium zinc oxide (MgZnO) deposited using a technique called radiofrequency co-sputtering (RF co-sputtering). Separate magnesium oxide (MgO) and zinc oxide (ZnO) targets were used to deposit the MgZnO film, experimenting with different deposition times and power levels. The sensor performed best (reaching a sensing response of 2.46) when exposed to hydrogen at a concentration of 1000 parts per million (ppm). This peak performance occurred with a MgZnO film thickness of 432 nanometers (nm) at a temperature of 300 °C. Initially, the sensor\'s responsiveness increased as the film thickness grew. This is because thicker films tend to have more oxygen vacancies, which are imperfections that play a role in the sensor\'s function. However, further increases in film thickness beyond the optimal point harmed performance. This is attributed to the growth of grains within the film, which hindered its effectiveness. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM) were employed to thoroughly characterize the quality of the MgZnO thin film. These techniques provided valuable insights into the film\'s crystal structure and morphology, crucial factors influencing its performance as a hydrogen sensor.
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  • 文章类型: Journal Article
    采用热合成方法制备了适合于光催化还原CO2协同制氢的CdS/TiO2玉米秸秆生物炭光催化复合材料。通过光生电子转移过程对这些复合材料的结构和协同反应进行了表征。与纯TiO2相比,最佳的CdS/TiO2玉米秸秆生物炭复合材料的能带隙降低到2.89eV。生物炭中TiO2和CdS之间的异质结构耦合加速了光生电子的转移,降低了光生电子和空穴的复合率。在可见光照射下,该CdS/TiO2玉米秸秆生物炭复合材料的光催化H2产率为1200µmol·h-1·g-1,CO产率为150µmol·h-1·g-1,CH4产率为55µmol·h-1·g-1。这种协同反应的关键是CdS和TiO2之间异质结的形成以及由生物炭的掺杂引起的复合材料中空穴的快速氧化。
    A thermal synthesis method was employed in this work to prepare CdS/TiO2 corn straw biochar photocatalytic composite materials suitable for synergistic hydrogen production with the photocatalytic reduction of CO2. The structure and synergistic reaction of these composite materials were characterized by its photogenerated electron transfer process. Compared with pure TiO2, the energy band gap of the optimal CdS/TiO2 corn straw biochar composite material was reduced to 2.89 eV. The heterostructure coupling between TiO2 and CdS in the biochar accelerated the transfer of photogenerated electrons and reduced the recombination rate of photogenerated electrons and holes. Under visible light irradiation, the photocatalytic H2 yield of this CdS/TiO2 corn straw-derived biochar composite material was 1200 µmol·h-1·g-1, the CO yield was 150 µmol·h-1·g-1, and the CH4 yield was 55 µmol·h-1·g-1. The key to this synergistic reaction is the formation of heterojunctions between CdS and TiO2 as well as the rapid oxidation of holes in the composite material caused by the doping of biochar.
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  • 文章类型: Journal Article
    等离子体气化熔化(PGM)提供低热值的有毒医疗废物的可靠处置,能够将废物转化为能源。这项研究调查了使用空气介质处理化学制药医疗废物(CPMW)的等离子体气化实验的性能。在三个反应器温度(1000、1400和1800°C)下对气化特性进行了比较分析。此外,建立了热力学平衡模型来评估合成气产量等性能特征,热值高,在1000-1800°C的气化温度范围内和冷气效率。实验和计算结果的比较显示出良好的一致性。结果表明,通过提高等离子气化炉的温度,使在1800°C,H2、CO、获得更高的热值(HHV)为41%,37%,和10MJ/Nm3。所获得的合成气是具有低含硫和含氮的清洁燃料。实验结果提供了对等离子体反应器中CPMW气化的广泛理解,并考虑了氢气和能源生产的可能性。
    Plasma gasification melting (PGM) provides reliable disposal of toxic medical waste with a low heating value, which is capable of converting waste into energy. This study investigates the performance of experiments on plasma gasification for the treatment of chemical-pharmaceutical medical waste (CPMW) with an air medium. A comparative analysis is performed for gasification characteristics at three reactor temperatures (1000, 1400, and 1800 °C). Moreover, a thermodynamic equilibrium model is developed to assess performance features such as syngas yield, high heating value, and cold gas efficiency in the gasification temperature range of 1000-1800 °C. A comparison of the experiment and computational outcomes shows a good agreement. The results show that the quality of syngas and heating value is improved by increasing the temperature of the plasma gasifier so that at 1800 °C, H2, CO, and higher heating value (HHV) are obtained as 41 %, 37 %, and 10 MJ/Nm3, respectively. The obtained syngas is a clean fuel with low sulfur-containing and nitrogen-containing. The experimental results provide an extensive comprehension of CPMW gasification in a plasma reactor and consider a possibility for hydrogen and energy production.
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  • 文章类型: Journal Article
    本文对Cu-BTTri的氢吸附性能进行了详细的研究,一个强大的结晶金属有机框架含有开放的金属配位位点。衍射技术,在激活的框架上进行,揭示了一个不同于以前报道的结构。Further,结合标准的氢吸附测量与原位中子衍射技术提供分子水平洞察氢吸附过程。衍射实验揭示了Cu-BTTri中四个D2吸附位点的位置,并阐明了促进该材料中氢吸附的结构特征。密度泛函理论(DFT),用于预测结合位点的位置和强度,证实实验结果。通过分解不同能量贡献中不同位点的结合能,我们表明范德华相互作用起着至关重要的作用,提出了增强开放金属配位位点周围结合能的可能途径。
    Herein we present a detailed study of the hydrogen adsorption properties of Cu-BTTri, a robust crystalline metal-organic framework containing open metal-coordination sites. Diffraction techniques, carried out on the activated framework, reveal a structure that is different from what was previously reported. Further, combining standard hydrogen adsorption measurements with in-situ neutron diffraction techniques provides molecular level insight into the hydrogen adsorption process. The diffraction experiments unveil the location of four D2 adsorption sites in Cu-BTTri and shed light on the structural features that promote hydrogen adsorption in this material. Density functional theory (DFT), used to predict the location and strength of binding sites, corroborate the experimental findings. By decomposing binding energies in different sites in various energetic contributions, we show that van der Waals interactions play a crucial role, suggesting a possible route to enhancing the binding energy around open metal coordination sites.
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  • 文章类型: Clinical Trial Protocol
    背景:动脉瘤性蛛网膜下腔出血(aSAH)是一种危及生命的神经外科急症,死亡率高。迟发性脑缺血(DCI)和脑血管痉挛(CVS)是早期脑损伤(EBI)的迟发性产品,这可能构成患者预后不良的主要决定因素。因此,DCI和CVS的缓解在追求改善患者预后方面具有至关重要的意义.然而,除了口服尼莫地平,目前的指南中没有有效的治疗方法.因此,迫切需要提供新的治疗范式。在基础研究中已经大量报道了氢治疗靶标的多样性,揭示了其改善aSAH患者EBI的潜在能力。
    方法:动脉瘤性蛛网膜下腔出血(HOMA)患者的早期氢-氧混合气体吸入,一个单一的中心,prospective,开放标签,随机对照临床试验,努力评估氢氧混合气体吸入疗法在aSAH患者中的有效性和安全性。将206名患者随机分为氢氧混合气体吸入组(每天8小时,3L/min,氢浓度为67%,氧浓度为33%)或吸氧组(每天8小时,3L/min,在aSAH后72小时内氧气浓度为33%),并在ICU病房治疗7天。主要结果是住院期间DCI和CVS的发生率。
    结论:HOMA旨在评估氢氧混合气体吸入疗法在预防DCI或CVS和改善aSAH患者预后方面的有效性。值得注意的是,这是首次在aSAH患者中进行氢气治疗的大规模试验.鉴于中国人口占全球人口的很大一部分,并且由于老龄化导致中风的发病率不断增加,优化患者护理至关重要。鉴于目前在aSAH患者预后方面的挑战,启动更多前瞻性临床试验至关重要.最近的研究表明氢的治疗潜力,与ASAH中的EBI对齐,推动我们探索氢气治疗动脉瘤破裂后损伤的机制。
    背景:HOMA研究方案获得北京天坛医院伦理委员会批准,首都医科大学(KY2022-020-02)。本研究的所有结果将发表在同行评审的期刊上,并在相关会议上发表。
    背景:ClinicalTrials.govNCT05282836。2022年3月16日注册。
    BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening neurosurgical emergency with a high mortality rate. Delayed cerebral ischemia (DCI) and cerebral vasospasm (CVS) are delayed products of early brain injury (EBI), which may constitute the principal determinant of an unfavorable patient prognosis. Consequently, the mitigation of DCI and CVS assumes paramount significance in the pursuit of enhanced patient outcomes. However, except for oral nimodipine, there is no effective therapy available in the current guideline. Hence, the exigency arises to proffer novel treatment paradigms. The diversity of hydrogen therapeutic targets has been largely reported in basic research, unveiling its latent capacity to ameliorate EBI in aSAH patients.
    METHODS: Early Hydrogen-Oxygen Gas Mixture Inhalation in Patients with Aneurysmal Subarachnoid Hemorrhage (HOMA), a single-center, prospective, open-labeled, randomized controlled clinical trial, endeavors to evaluate the efficacy and safety of hydrogen-oxygen gas mixture inhalation therapy in aSAH patients. A cohort of 206 patients will be randomized to either hydrogen-oxygen gas mixture inhalation group (8 h per day, 3 L/min, hydrogen concentration of 67%, oxygen concentration of 33%) or oxygen inhalation group (8 h per day, 3 L/min, oxygen concentration of 33%) within 72 h after aSAH and treated for 7 days in the ICU ward. The primary outcomes are the incidence of DCI and CVS during hospitalization.
    CONCLUSIONS: The HOMA aims to evaluate the effectiveness of hydrogen-oxygen gas mixture inhalation therapy in preventing DCI or CVS and improving outcomes in aSAH patients. Notably, this is the first large-scale trial of hydrogen therapy in aSAH patients. Given that the Chinese population represents a significant portion of the global population and the increasing incidence of stroke due to aging, optimizing patient care is vital. Given the current challenges in aSAH patient outcomes, initiating more prospective clinical trials is essential. Recent research has shown hydrogen\'s therapeutic potential, aligning with EBI in aSAH, driving our exploration of hydrogen therapy\'s mechanisms in post-aneurysm rupture damage.
    BACKGROUND: The protocol for the HOMA study was approved by the Ethics Committee of Beijing Tiantan Hospital, Capital Medical University (KY 2022-020-02). All results of the present study will be published in peer-reviewed journals and presented at relevant conferences.
    BACKGROUND: ClinicalTrials.gov NCT05282836. Registered on March 16, 2022.
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  • 文章类型: Journal Article
    全球航运业面临压力,需要转向更绿色的推进和燃料技术,以减少温室气体排放。氢和电都被认为是实现净零的途径。然而,在评估这些替代海洋电力配置的环境性能时,传统的生命周期评估(LCA)方法具有局限性,反映了船舶设计和运营模式的多样性。LCA与实验评估的集成可以弥补传统数据生成方法的缺点。本研究中的系统能源需求数据是根据特定的船舶设计生成的,并直接输入到生命周期评估中。为了证明该方法的有效性和潜力,该方法被应用于内河船舶的案例研究。为案例船建立了合适的混合PV/电力/柴油和氢动力燃料电池系统模型;并进行了水动力测试和动态系统模拟,以提供各种操作/环境概况下的船舶性能数据。生命周期评估(LCA)表明,与MGO基本情况相比,氢和电力推进技术有可能减少85.7%和56.2%的排放。分别。结果强调,这两种技术的实施都高度依赖于能源生产途径。相对于MGO基本情况,依赖化石原料的氢系统可能会增加高达6.3%的排放量。敏感性分析表明,与MGO基本情况相比,79.5%可再生能源发电的电气系统可以节省82.2%的温室气体排放。至关重要的是,结果表明,LCA方法的进一步发展,可以在考虑特定船舶设计和操作特性的情况下,对替代船舶动力配置进行更准确的环境性能评估。最终,这种增加使结果对于选择替代船舶电力系统以支持向零净值过渡的商业运营和决策更有意义。
    There is pressure on the global shipping industry to move towards greener propulsion and fuel technologies to reduce greenhouse gas emissions. Hydrogen and electricity are both recognised as pathways to achieve a net-zero. However, in the evaluation of the environmental performance of these alternative marine power configurations, conventional life cycle assessment (LCA) methods have limitations reflecting the varied nature of ship design and operational modes. The integration of LCA with experimental assessment could remedy the shortcoming of conventional approaches to data generation. The system energy demand data in this study was generated based on specific ship design and directly fed into life cycle assessment. To demonstrate the effectiveness and potential the approach was applied to a case study of inland waterway vessel. Suitable hybrid PV/electricity/diesel and hydrogen powered fuel cell systems for the case vessel were modelled; and hydrodynamic testing and dynamic system simulation was undertaken to provide ship performance data under various operational/environmental profiles. Lifecycle assessment (LCA) indicated hydrogen and electrical propulsion technologies have the potential for 85.7 % and 56.2 % emissions reduction against an MGO base case, respectively. The results highlight that implementation of both technologies is highly dependent on energy production pathways. Hydrogen systems reliant on fossil feedstocks risk an increase in emissions of up to 6.3 % against the MGO base case. Sensitivity analysis indicated an electrical system with electricity production from 79.5 % renewables could achieve savings of 82.2 % in GHG emissions compared to the MGO base case. Crucially, the results demonstrate a further development of the LCA approach which can enable a more accurate environmental performance evaluation of alternative marine power configurations considering specific ship design and operational characteristics. Ultimately this addition makes the results more meaningful for commercial operations and decision making in the selection of alternative marine power systems to support the transition to net-zero.
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  • 文章类型: Journal Article
    (1)背景:氢气(H2)由于其抗氧化和抗炎特性,可能是治疗长COVID症状的潜在治疗剂。然而,需要更多的科学文献来描述H2给药对症状的治疗效果。一项研究旨在调查连续14天服用富氢水(HRW)对长COVID患者疲劳和呼吸困难的影响。(2)方法:在本随机分组中,单盲,安慰剂对照研究,招募了55名参与者,其中23人被排除在外。共有32名符合条件的参与者被随机分为富氢水(HRW)组(n=16)和安慰剂水(PW)组(n=16),他们被指示食用富氢水或安慰剂水14天,分别。参与者完成了疲劳严重程度量表(FSS),六分钟步行测试(6MWT),30s椅架测试(30s-CST),改良医学研究委员会呼吸困难量表(mMRC),匹兹堡睡眠质量指数(PSQI)干预前后抑郁焦虑应激量表(DASS-21)。采用线性混合效应模型对HRW的影响进行了分析。当观察到显著性时,Cohen'sd值用于评估效应大小。还报告了95%置信区间(95%CI)的平均变化。(3)结果:HRW降低FSS评分(p=0.046,[95%CI=-20.607,-0.198,d=0.696]和改善6WMT的总距离(p<0.001,[95%CI=41.972,61.891],d=1.010),30s-CST的总时间(p=0.002,[95%CI=1.570,6.314],d=1.190),和PSQI得分(p=0.012,[95%CI=-5.169,0.742],d=1.274)与PW相比具有显著的中等效应大小,而mMRC评分(p=0.556)或DASS-21评分(p>0.143)无显著差异。(4)结论:本研究表明,HRW可能是缓解疲劳和提高心肺耐力的有效策略。肌肉骨骼功能,和睡眠质量。尽管如此,它不能改善Long-COVID患者的呼吸困难。
    (1) Background: Hydrogen (H2) may be a potential therapeutic agent for managing Long COVID symptoms due to its antioxidant and anti-inflammatory properties. However, more scientific literature is needed to describe the effects of H2 administration on treating symptoms. A study aimed to investigate the impact of hydrogen-rich water (HRW) administration on the fatigue and dyspnea of Long-COVID patients for 14 consecutive days. (2) Methods: In this randomized, single-blind, placebo-controlled study, 55 participants were recruited, and 23 of them were excluded. A total of 32 eligible participants were randomized into a hydrogen-rich water (HRW) group (n = 16) and a placebo water (PW) group (n = 16) in which they were instructed to consume hydrogen-rich water or placebo water for 14 days, respectively. The participants completed the Fatigue Severity Scale (FSS), Six-Minute Walk Test (6MWT), 30 s Chair Stand Test (30s-CST), Modified Medical Research Council Dyspnea Rating Scale (mMRC), Pittsburgh Sleep Quality Index (PSQI), and depression anxiety stress scale (DASS-21) before and after the intervention. A linear mixed-effects model was used to analyze the effects of HRW. Cohen\'s d values were used to assess the effect size when significance was observed. The mean change with 95% confidence intervals (95% CI) was also reported. (3) Results: The effects of HRW on lowering FSS scores (p = 0.046, [95% CI = -20.607, -0.198, d = 0.696] and improving total distance in the 6WMT (p < 0.001, [95% CI = 41.972, 61.891], d = 1.010), total time for the 30s-CST (p = 0.002, [95% CI = 1.570, 6.314], d = 1.190), and PSQI scores (p = 0.012, [95% CI = -5.169, 0.742], d = 1.274) compared to PW were of a significantly moderate effect size, while there was no significant difference in mMRC score (p = 0.556) or DASS-21 score (p > 0.143). (4) Conclusions: This study demonstrates that HRW might be an effective strategy for alleviating fatigue and improving cardiorespiratory endurance, musculoskeletal function, and sleep quality. Still, it does not ameliorate dyspnea among Long-COVID patients.
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  • 文章类型: Journal Article
    最大的人为二氧化碳排放源是全球能源系统,这意味着改变全球能源系统是减少温室气体排放和缓解气候变化的最重要方法之一。建筑在我们向低碳未来的过渡中起着至关重要的作用,约占全球能源消耗的47%,约占全球温室气体排放量的25%。可再生氢气是能源生产中最环保的选择之一。这项研究提出了一个充满活力的,经济,以及建筑物中可再生能源生产的自给自足系统对环境的影响。为了实现这一目标,选择了基于氢气的发电系统,以满足全年阿尔及利亚三级建筑的所有电气要求。结果表明,混合可再生能源系统每年可以避免约1056吨二氧化碳的排放。此外,投资回收期为7年。这些结果清楚地表明,在建筑物中整合氢能是环境可持续性的最佳选择。
    The largest anthropogenic source of carbon dioxide emissions is the global energy system, which means transforming the global energy system is one of the most significant ways to reduce greenhouse gas emissions and mitigate climate change. Buildings play a critical role in our transition to a lower-carbon future, accounting for approximately 47% of global energy consumption and about 25% of global greenhouse gas emissions. Renewable hydrogen represents one of the most environmentally friendly options for energy generation. This study presents an energetic, economic, and environmental impact of a self-sufficient system for energy production from renewable energy sources in buildings. To achieve this objective, a hydrogen-based generation system was selected to meet all the electrical requirements of tertiary building in Algeria throughout the year. The results indicate that the hybrid renewable energy system can avoid the emission of approximately 1056 tons of carbon dioxide per year. Furthermore, the payback period is 7 years. These results clearly demonstrate that the integration of hydrogen energy in buildings is the optimal choice for environmental sustainability.
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  • 文章类型: Journal Article
    研究氢气渗透对氢气设备密封材料摩擦特性的影响,建立了10%PEEK/PTFE复合材料的分子模型及其摩擦模型,分别,和分子动力学(MD)和巨规范蒙特卡罗(GCMC)方法来模拟扩散系数,PEEK/PTFE复合材料中氢的溶解系数和渗透系数。还研究了不同氢含量对PEEK/PTFE复合材料摩擦磨损的影响。结果表明,氢气的渗透主要表现出对PEEK/PTFE复合材料表面的积极影响,PEEK/PTFE复合材料的磨损率呈小幅下降趋势。当更多的氢分子渗入基体时,PEEK/PTFE复合材料的磨损率逐渐降低。随着氢分子的进一步渗透,PEEK/PTFE复合材料的磨损率和摩擦系数迅速增加,表现出负面影响。随着氢分子的进一步渗透,复合材料的摩擦系数呈现较小的波动,然后迅速下降的趋势。同时,提出了有效的改进措施,并验证了石墨烯的引入能有效降低氢气渗透的负面影响,从而提高PEEK/PTFE复合材料的摩擦性能。
    To research the effect of hydrogen permeation on the friction characteristics of the seal materials on the hydrogen equipment, the molecular models of 10% PEEK/PTFE composites and its frictional models were established, respectively, and molecular dynamics (MDs) and giant canonical Monte Carlo (GCMC) methods were used to simulate the diffusion coefficient, dissolution coefficient and permeability coefficient of the hydrogen in PEEK/PTFE composites. The effect of a different amount of hydrogen on the friction and wear of PEEK/PTFE composites was also studied. The results showed that few permeations of the hydrogen gas mainly demonstrated having a positive effect on the surface of the PEEK/PTFE composites, and the wear rate of the PEEK/PTFE composites showed a slight decreasing trend. The wear rate of the PEEK/PTFE composites gradually decreased when more hydrogen molecules penetrated the matrix. With the further penetration of the hydrogen molecules, the wear rate and friction coefficient of the PEEK/PTFE composites rapidly increased, showing a negative effect. With the further penetration of the hydrogen molecule, the friction coefficient of the composite displayed a small fluctuation and then a rapid decreasing trend. Meanwhile, effective improvement measures were proposed, and the introduction of the graphene was verified to be effective to reduce the negative effect of the hydrogen permeation, thereby improving the friction performance of the PEEK/PTFE composites.
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  • 文章类型: Journal Article
    这项研究旨在通过检查通常用于此目的的聚合物中的氢的渗透特性和机理,为氢输送管道衬里材料的选择和安全应用提供理解。如高密度聚乙烯(HDPE)和乙烯-乙烯醇共聚物(EVOH),通过分子模拟。该研究是在与氢气管道基础设施相关的温度(从室温到80°C)和压力(从2.5到10MPa)的定义操作参数范围内进行的。结果表明,随着温度从30°C升高到80°C,溶解度,扩散,HDPE中氢气的渗透系数增加了18.7%,92.9%,和129.0%,分别。同样,在EVOH,这些系数的增量为15.9%,81.6%,和112.7%。相反,压力变化对两种聚合物的渗透率影响可忽略不计。与EVOH相比,HDPE表现出显著更高的氢渗透性。EVOH独特的链段结构导致羟基之间形成强大的氢键,从而阻碍氢的渗透。氢被吸附在聚合物中的过程涉及在低势能水平下的聚集。在扩散过程中,氢分子主要在有限范围内振动,在较大的距离上间歇性地发生显著的孔-孔过渡。与EVOH相比,氢与HDPE表现出更强的相互作用,导致HDPE中更多的吸附位点和增加的氢吸附容量。氢分子在HDPE中比在EVOH中更活跃,在扩散过程中表现出更大的空穴幅度和更多的空穴过渡。
    This research aimed to provide an understanding of the selection and safe application of pipeline liner materials for hydrogen transport by examining the permeation properties and mechanisms of hydrogen within polymers commonly used for this purpose, such as high-density polyethylene (HDPE) and ethylene-vinyl alcohol copolymer (EVOH), through molecular simulation. The study was carried out within defined operational parameters of temperature (ranging from room temperature to 80 °C) and pressure (from 2.5 to 10 MPa) that are pertinent to hydrogen pipeline infrastructures. The results reveal that with an increase in temperature from 30 °C to 80 °C, the solubility, diffusion, and permeability coefficients of hydrogen in HDPE increase by 18.7%, 92.9%, and 129.0%, respectively. Similarly, in EVOH, these coefficients experience increments of 15.9%, 81.6%, and 112.7%. Conversely, pressure variations have a negligible effect on permeability in both polymers. HDPE exhibits significantly higher hydrogen permeability compared to EVOH. The unique chain segment configuration of EVOH leads to the formation of robust hydrogen bonds among the hydroxyl groups, thereby impeding the permeation of hydrogen. The process by which hydrogen is adsorbed in polymers involves aggregation at low potential energy levels. During diffusion, the hydrogen molecule primarily vibrates within a limited range, with intermittent occurrences of significant hole-to-hole transitions over larger distances. Hydrogen exhibits a stronger interaction with HDPE compared to EVOH, leading to a higher number of adsorption sites and increased hydrogen adsorption capacity in HDPE. Hydrogen molecules move more actively in HDPE than in EVOH, exhibiting greater hole amplitude and more holes in transition during the diffusion process.
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