atmosphere

大气
  • 文章类型: Journal Article
    内部大气波是重力波,发生在流体系统的内部。在这项研究中,使用Caputo-Fabrizio时间分数阶微分算子研究了内部大气波的时间分数模型。通过ElzakiAdomian分解方法检索所考虑模型的解析解。通过数值和图形模拟来检查解的变化,以增加分数参数α的阶数。通过将所考虑的分数模型的解决方案与文献中可用的结果进行比较,可以确定所获得结果的准确性。
    The internal atmospheric waves are gravity waves and occur in the inner part of the fluid system. In this study, a time-fractional model for internal atmospheric waves is investigated with the Caputo-Fabrizio time-fractional differential operator. The analytical solution of the considered model is retrieved by the Elzaki Adomian decomposition method. The variation in the solution is examined for increasing order of the fractional parameter α through numerical and graphical simulations. The accuracy of the obtained results is established by comparing the obtained solution of considered fractional model with the results available in the literature.
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  • 文章类型: Journal Article
    植物从叶子上的矿物质粉尘中吸收养分的能力可能被证明是植物应对大气中不断增加的CO2水平的重要机制。这种机制直到最近才被报道,并被证明可以补偿植物离子组中预计的稀释。然而,这种现象还有待深入研究,特别是在不同粉尘类型和不同大气CO2浓度下的预期趋势方面,正如IPCC预测的那样。我们用沙漠粉尘处理了在环境(415ppm)和升高的CO2(850ppm)条件下生长的植物,火山灰,和火灰类似物,只应用在植物叶子上,并研究了它们的稀土元素浓度和模式。处理过的植物的稀土元素成分来自粉尘的应用,它们与植物的结合导致了植物活力的显著增加,光合活性和生物量增加明显。稀土元素揭示了叶面养分吸收机制的两个趋势,一是不同处理对植物的影响顺序为火山灰>沙漠粉尘>火灰。第二个趋势是,在CO2升高的情况下,叶面摄入量变得更加明显,这是以前从未见过的观察结果。这证明了稀土元素在叶面养分吸收研究中的应用,和其他生物机制是基本的,并且在预期的大气变化下,随着CO2的增加,养分吸收的叶面途径确实会变得更加占主导地位。
    The ability of plants to uptake nutrients from mineral dust lying on their foliage may prove to be an important mechanism by which plants will cope with increasing CO2 levels in the atmosphere. This mechanism had only recently been reported and was shown to compensate for the projected dilution in plants ionome. However, this phenomenon has yet to be thoroughly studied, particularly in terms of the expected trends under different dust types and varying atmospheric CO2 concentrations, as projected by the IPCC. We treated plants grown under ambient (415 ppm) and elevated CO2 (850 ppm) conditions with either desert dust, volcanic ash, and fire ash analogues by applying it solely on plant foliage and studied their Rare Earth Elements concentrations and patterns. The Rare Earth Elements compositions of the treated plants originated from the dust application, and their incorporation into the plants led to a significant increase in plants vitality, evident in increased photosynthetic activity and biomass. Two trends in the foliar nutrient uptake mechanism were revealed by the Rare Earth Elements, one is that different treatments affected the plant in decreasing order volcanic ash > desert dust > fire ash. The second trend is that foliar intake becomes more significant under elevated CO2, an observation not previously seen. This testifies that the use of Rare Earth Elements in the study of foliar nutrient uptake, and other biological mechanisms is fundamental, and that foliar pathways of nutrient uptake will indeed become more dominant with increasing CO2 under expected atmospheric changes.
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  • 文章类型: Journal Article
    空气污染受到大气动力学的影响。这项研究旨在确定伊斯坦布尔的空气污染浓度值显着增加,并由于2022年12月30日至2023年1月5日之间的大气阻塞而达到峰值。在这项研究中,每小时污染物数据来自16个空气质量监测站(AQMS),准确的重新分析数据是从ERA5数据库中提取的,和反转水平以及气象和天气分析用于确定大气阻塞对空气污染的影响。此外,云基高度和垂直能见度测量是用测高仪进行的。使用R和Grads程序进行统计计算和数据可视化。欧米茄型阻塞,2022年12月30日在伊斯坦布尔开始,对2023年1月1日和2日产生了重大影响,PM10和PM2.5浓度值分别达到了572.8和254.20µg/m3的峰值。此外,发现几乎所有站点在检查期间的平均浓度值都高于1月和2月的平均值。因此,在这些日历日期之间,伊斯坦布尔的空气质量被确定为“差”。发现阻塞不影响臭氧(μg/m3)浓度。还发现,伊斯坦布尔地区的阻塞效应增加了直径为10µm或更小(PM10)的颗粒物(PM)和直径为2.5µm或更小(PM2.5)的浓度。最后,根据使用测高仪获得的数据,云基高度降至30m,垂直能见度降至10m。
    Air pollution is affected by the atmospheric dynamics. This study aims to determine that air pollution concentration values in İstanbul increased significantly and reached peak values due to atmospheric blocking between the 30th of December 2022 and the 5th of January 2023. In this study, hourly pollutant data was obtained from 16 air quality monitoring stations (AQMS), the exact reanalysis data was extracted from ERA5 database, and inversion levels and meteorological and synoptic analyses were used to determine the effects of atmospheric blocking on air pollution. Also, cloud base heights and vertical visibility measurements were taken with a ceilometer. Statistical calculations and data visualizations were performed using the R and Grads program. Omega-type blocking, which started in İstanbul on December 30, 2022, had a significant impact on the 1st and 2nd of January 2023, and PM10 and PM2.5 concentration values reached their peak values at 572.8 and 254.20 µg/m3, respectively. In addition, it was found that the average concentration values in the examined period in almost all stations were higher than the averages for January and February. As a result, air quality in İstanbul was determined as \"poor\" between these calendar dates. It was found that the blocking did not affect the ozone (µg/m3) concentration. It was also found that the concentrations of particulate matter (PM) 10 µm or less in diameter (PM10) and PM 2.5 µm or less in diameter (PM2.5) were increased by the blocking effect in the İstanbul area. Finally, according to the data obtained using the ceilometer, cloud base heights decreased to 30 m and vertical visibility to 10 m.
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  • 文章类型: Journal Article
    异戊二烯是在代谢过程的生物合成过程中排放的最相关的挥发性有机化合物。异戊二烯被羟基自由基(OH)氧化是产生异戊二烯羟基氢过氧化物自由基(ISOPOO)的六种异构体的主要消耗方案之一。在这项研究中,最终生成三氧化硫(SO3)的ISOPOOs+二氧化硫(SO2)反应的速率常数,硫酸盐气溶胶的前体(SO42-(P)),使用微规范动力学理论以及通过量子化学计算估算的分子结构和能量确定。结果表明,反应速率范围为10-27至10-20cm3分子-1s-1,具体取决于大气温度和六种ISOPOO异构体的结构。通过全球化学传输模型评估了ISOPOOs对SO2氧化形成SO3对大气的影响,以及从微规范动力学理论获得的速率常数。结果表明,高SO2或低氮氧化物(NO)区域的SO3形成增强,比如中国,中东,亚马逊雨林。然而,ISOPOOsSO2反应形成SO3的生产率比OHSO2反应低8个数量级。这表明ISOPOO直接氧化SO2形成SO42-(p),这在大气中几乎可以忽略不计。这项研究的结果需要详细分析异戊二烯衍生产物的气相反应中SO3的形成。
    Isoprene is the most relevant volatile organic compound emitted during the biosynthesis of metabolism processes. The oxidation of isoprene by a hydroxy radical (OH) is one of the main consumption schemes that generate six isomers of isoprene hydroxy hydroperoxide radicals (ISOPOOs). In this study, the rate constants of ISOPOOs + sulphur dioxide (SO2) reactions that eventually generate sulphur trioxide (SO3), the precursor of sulphate aerosol (SO42-(p)), are determined using microcanonical kinetic theories coupled with molecular structures and energies estimated by quantum chemical calculations. The results show that the reaction rates range from 10-27 to 10-20 cm3 molecule-1 s-1, depending on the atmospheric temperature and structure of the six ISOPOO isomers. The effect of SO3 formation from SO2 oxidation by ISOPOOs on the atmosphere is evaluated by a global chemical transport model, along with the rate constants obtained from microcanonical kinetic theories. The results show that SO3 formation is enhanced in regions with high SO2 or low nitrogen oxide (NO), such as China, the Middle East, and Amazon rainforests. However, the production rates of SO3 formation by ISOPOOs + SO2 reactions are eight orders of magnitude lower than that from the OH + SO2 reaction. This is indicative of SO42-(p) formation from the direct oxidation of SO2 by ISOPOOs, which is almost negligible in the atmosphere. The results of this study entail a detailed analysis of SO3 formation from gas-phase reactions of isoprene-derived products.
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  • 文章类型: Journal Article
    农药广泛用于农业,但是它们对环境和人类健康的影响是一个主要问题。虽然人们对它们在土壤中的存在给予了很大的关注,水,和食物,在全球范围内,关于空气中农药污染的研究很少。这项研究旨在评估全球各国大气农药污染的程度,并使用评分方法确定区域差异。除了分析与农药污染相关的健康风险,我们还研究了这些国家的农业实践和当前的农药空气质量标准。各国的污染得分差异很大,尤其是在欧洲。与美洲国家相比,亚洲和海洋国家的得分普遍较高,这表明这些地区的农药造成的空气污染水平相对较高。值得注意的是,目前的污染水平,从理论上评估,对人类的健康风险最小。然而,文献中的研究表明,过度暴露于大气中存在的农药与各种健康问题有关,比如癌症,神经精神疾病,和其他慢性疾病。有趣的是,欧洲国家的整体农药施用强度最高,但这并不一定对应于更高的大气农药污染分数。只有少数国家制定了专门针对农药的空气质量标准。此外,调查了美国各州的污染分数,并绘制了全球采样点。调查结果显示,美国的分数差异很大,目前的采样地点在一些国家有限或分布不均,尤其是北欧国家。这些发现可以帮助全球相关环境机构建立全面的监测网络。总的来说,本研究强调需要建立农药监测系统,并加大力度加强农药监管,确保标准的一致性,促进国际合作。
    Pesticides are widely used in agriculture, but their impact on the environment and human health is a major concern. While much attention has been given to their presence in soil, water, and food, there have been few studies on airborne pesticide pollution on a global scale. This study aimed to assess the extent of atmospheric pesticide pollution in countries worldwide and identify regional differences using a scoring approach. In addition to analyzing the health risks associated with pesticide pollution, we also examined agricultural practices and current air quality standards for pesticides in these countries. The pollution scores varied significantly among the countries, particularly in Europe. Asian and Oceanic countries generally had higher scores compared to those in the Americas, suggesting a relatively higher level of air pollution caused by pesticides in these regions. It is worth noting that the current pollution levels, as assessed theoretically, pose minimal health risks to humans. However, studies in the literature have shown that excessive exposure to pesticides present in the atmosphere has been associated with various health problems, such as cancer, neuropsychiatric disorders, and other chronic diseases. Interestingly, European countries had the highest overall pesticide application intensities, but this did not necessarily correspond to higher atmospheric pesticide pollution scores. Only a few countries have established air quality standards specifically for pesticides. Furthermore, pollution scores across states in the USA were investigated and the global sampling sites were mapped. The findings revealed that the scores varied widely in the USA and the current sampling sites were limited or unevenly distributed in some countries, particularly the Nordic countries. These findings can help global relevant environmental agencies to set up comprehensive monitoring networks. Overall, the present research highlights the need to create a pesticide monitoring system and increase efforts to enhance pesticide regulation, ensure consistency in standards, and promote international cooperation.
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  • 文章类型: Journal Article
    这项研究旨在调查八种亚硝胺(NAs)在颗粒(PM2.5)和气相中的发生,并评估与这些化合物在春川市区相关的人类健康风险,江原州,韩国,在四个采样季节。调查结果显示,在采样期间测量的8种无氧化合物的总浓度超过了挪威公共卫生研究所提供的0.3纳克/立方米的公共卫生建议,表明NA暴露存在潜在的人类健康风险。特别是,2021年冬季在气态样品中观察到的平均总NA浓度为18.1±6.46ng/m3。主要排放源可能会影响大气中NAs的浓度,因为它们与NO2、CO、和SO2。此外,夏季颗粒NAs的水平与O3呈负相关,表明它们的形成可能受到气溶胶水相臭氧的影响。此外,在整个采样期间,气相中测得的总NA浓度比PM2.5中测得的高4至6倍。因此,与远距离大气传输相比,国内来源有可能对研究区域的污染水平产生更大的影响。特别是,在冬季观察到气相中的最高浓度的NAs,虽然最低浓度记录在夏季,可能受光解的影响。然而,该研究表明,叔胺可能有助于在阳光下存在气态NA。因此,应考虑对气相中叔胺的存在进行进一步研究。在所有四个季节中,吸入暴露估计的累积终生癌症风险超过了所有年龄组的可接受风险水平10-6。因此,实施有效的控制措施以减轻与暴露于NAs相关的潜在健康风险至关重要。
    This study aimed to investigate the occurrence of eight nitrosamines (NAs) in particulate (PM2.5) and gaseous phases and assess the human health risk associated with these compounds in an urban area of Chuncheon, Gangwon State, South Korea, across four sampling seasons. The findings revealed that the total concentrations of eight NAs measured during the sampling period exceeded the public health recommendation of 0.3 ng/m3 provided by the Norwegian Institute of Public Health, indicating a potential human health risk from NA exposures. In particular, the average total NA concentration observed in the gaseous samples during the winter of 2021 was 18.1 ± 6.46 ng/m3. The primary emission sources could potentially impact the concentrations of NAs in the atmosphere due to their significant positive correlation with primary emission species such as NO2, CO, and SO2. Moreover, the levels of particulate NAs during the summer were negatively correlated with O3, suggesting that their formation might be influenced by ozonation in the aqueous aerosol phase. In addition, the total NA concentrations measured in the gaseous phase were four to six times higher than those measured in the PM2.5 phase throughout the sampling period. Thus, domestic sources have the potential to impact the pollution levels of the research area more significantly than long-range atmospheric transport. In particular, the highest concentrations of NAs in the gas phase were observed during the winter, while the lowest concentrations were recorded in the summer, possibly influenced by photolysis. Nevertheless, the study suggested that tertiary amines might contribute to the presence of gaseous NAs in sunlight. Consequently, further studies focusing on the occurrence of tertiary amines in the gas phase should be considered. The cumulative lifetime cancer risks estimated from inhalation exposure exceeded the acceptable risk level of 10⁻6 for all age groups across all four seasons. Therefore, it is crucial to implement effective control measures to mitigate potential health risks associated with exposure to NAs.
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  • 文章类型: Journal Article
    目的:探讨护士在医疗环境中实施循证实践(EBP)的经验和观点。
    方法:使用焦点小组讨论(FGD)的定性描述性研究设计。
    方法:有目的地选择并在Bisha省的各种医疗机构工作的64名护士,沙特阿拉伯,包括在内。使用八个FGD使用开放式问题获得数据。对收集的数据进行归纳定性内容分析。
    结果:提取了两个主要类别:对EBP的经验和观点。经验类别分为四个子类别:熟悉概念和好处,steps,EBP的传播源和EBP知识的来源,虽然对EBP类别的观点包括四个子类别:EBP在临床实践中的应用,障碍,促进者和EBP应用方法。由于缺乏对EBP实施的组织承诺,参与者经历了非支持性和非令人鼓舞的气氛,并阐明了整合过程中涉及的复杂性。
    结论:护士对EBP的经验表明,对实施这种方法的支持有限。此外,他们在实施EBP方面遇到了不同的障碍。他们认为EBP是一种复杂的技术,因为他们缺乏与研究问题的制定相关的知识和技能,和检索,EBP在临床实践决策中的应用和传播。这是由于与个人相关的障碍,组织和患者因素。在护理实践中成功实施EBP的关键是促进专业发展,全面和持续的培训,变革的文化,组织支持和激励。
    结论:通过构建和提供有关EBP的持续教育干预和指导计划,医疗保健组织和护理领导可以制定一个全面的策略来鼓励员工护士参与EBP过程。这是为了增强护士对EBP方法的经验和观点,并克服有效实施的障碍。
    患者或公众没有参与设计,分析或解释本研究中的数据。
    OBJECTIVE: To explore nurses\' experiences and perspectives about evidence-based practice (EBP) implementation in the healthcare context.
    METHODS: A qualitative descriptive study design using focus group discussions (FGDs).
    METHODS: Sixty-four nurses who purposefully selected and worked at various healthcare organizations in Bisha Governorate, Saudi Arabia, were included. Eight FGDs were used to obtain data using open-ended questions. The collected data underwent inductive qualitative content analysis.
    RESULTS: Two main categories were extracted: experiences and perspectives towards EBP. The experiences category emerged into four sub-categories: familiarity with concepts and benefits, steps, dissemination sources of EBP and sources of EBP knowledge, while perspectives towards the EBP category included four sub-categories: application of EBP in clinical practice, barriers, facilitators and EBP application methods. The participants experienced being in a non-supportive and non-encouraging atmosphere which results from a lack of organizational commitment to EBP implementation and illuminates the complexities involved in the integration process.
    CONCLUSIONS: The nurses\' experience with EBP indicated that there was limited support for the implementation of this approach. Furthermore, they experienced varying barriers to EBP implementation. They viewed EBP as a complex technique as they lacked knowledge and skills related to the formulation of research questions, and retrieving, applying and disseminating of EBP in clinical practice decision-making. That is due to barriers pertinent to the individual, organizational and patient factors. The key to successfully implementing an EBP in nursing practice is to promote professional development, comprehensive and continuous training, a culture of change, organizational support and motivation.
    CONCLUSIONS: Through the construction and provision of ongoing educational interventions and mentoring programmes about EBP, healthcare organizations and nursing leadership may develop a comprehensive strategy to encourage staff nurses\' participation in the EBP process. This is to enhance nurses\' experiences and perspectives towards the EBP approach and overcome the barriers to effective implementation.
    UNASSIGNED: Patients or the general public were not involved in the design, analysis or interpretation of the data in this study.
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  • 文章类型: Journal Article
    作为挥发性有机化合物(VOCs),五甲基苯(5-PeMB)和六甲基苯(6-HeMB)广泛存在于石油和煤焦油中。通过燃烧和工业发电进入大气,它们会产生光化学烟雾和二次有机气溶胶(SOA),最终危害人类健康和生态环境。为了揭示它们的环境化学性质,基于密度泛函理论(DFT)研究了5-PeMB和6-HeMB的OH引发降解机理。结果表明,加成反应途径最有利,能垒分别为20.7和25.3kJ/mol,分别,在两个反应中。在298K下的降解速率常数计算为2.69×10-10和1.28×10-10cm3分子-1·s-1,与可用的实验值一致。在OH自由基的存在下,大气寿命估计为2.17和2.78小时,分别,用于5-PeMB和6-HeMB。根据定量构效关系(QSAR)模型,降解过程中的毒性在鱼类中降低,水蚤,和绿藻。
    As volatile organic compounds (VOCs), pentamethylbenzene (5-PeMB) and hexamethylbenzene (6-HeMB) are found widely in petroleum and coal tar. Through combustion and industrial generation entering into the atmosphere, they can produce photochemical smog and secondary organic aerosols (SOA) to endanger human health and ecoenvironment eventually. In order to reveal their environmental chemistry, the OH-initiated degradation mechanisms of 5-PeMB and 6-HeMB were studied based on density functional theory (DFT). Result showed that addition pathways were the most favorable with energy barriers of 20.7 and 25.3 kJ/mol, respectively, in the two reactions. The degradation rate constants at 298 K were calculated to be 2.69 × 10-10 and 1.28 × 10-10 cm3 molecule-1 ·s-1, coinciding with the available experimental values. In the presence of OH radicals, the atmospheric lifetimes were estimated to be 2.17 and 2.78 h, respectively, for 5-PeMB and 6-HeMB. According to the quantitative structure-activity relationship (QSAR) model, the toxicity during the degradation process is decreased to fish, daphnia, and green algae.
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  • 文章类型: Journal Article
    Hymexazol是一种广泛用于农业的挥发性杀菌剂,导致其在大气中的丰富;因此,在评估其环境影响时,其大气命运和转换非常重要。在这里,我们报道了羟基自由基氧化hymexazol的理论动力学机制,以及通过在ROCBS-QB3//M06-2X上探索的势能面上使用基于Rice-Ramsperger-Kassel-Marcus的主方程动力学模型,以及其主要产物与O2然后与NO的后续反应。/aug-cc-pVTZ水平。预测的总速率常数ktotal(T,P)对于hymexazol和OH自由基之间的反应,与几乎无法获得的实验值显示出极好的一致性(例如,在T=300K和P=760Torr时,3.6×10-12vs(4.4±0.8)×10-12cm3/分子/s);因此,计算的动力学参数可以可靠地用于在大气甚至燃烧条件下的N-杂环相关应用的建模/模拟。模型显示3,4-二羟基-5-甲基-4,5-二氢-1,2-恶唑-5-基(IM2),3,5-二羟基-5-甲基-4,5-二氢-1,2-恶唑-4-基(IM3),和(3-羟基-1,2-恶唑-5-基)甲基(P8)是主要的主要中间体,形成(3,4-二羟基-5-甲基-4,5-二氢-1,2-恶唑-5-基)二氧化二烷基(IM4)的主要二级物种,(3,5-二羟基-5-甲基-4,5-二氢-1,2-恶唑-4-基)二氧杂烷基(IM7),和([(3-羟基-1,2-恶唑-5-基)甲基]二氧杂烷基(IM11),分别,通过与O2的反应。然后,主要的二级物种可以与NO反应形成主要的三级物种,即,(3,4-二羟基-5-甲基-4,5-二氢-1,2-恶唑-5-基)氧化烷基(P19),(3,5-二羟基-5-甲基-4,5-二氢-1,2-恶唑-4-基)氧化烷基(P21),和[(3-羟基-1,2-恶唑-5-基)甲基]氧化烷基(P23),分别,与NO2此外,hymexazol可能是对流层中的持久性有机污染物,因为其计算的半衰期τ1/2为13.7-68.1h,取决于海拔高度。
    Hymexazol is a volatile fungicide widely used in agriculture, causing its abundance in the atmosphere; thus, its atmospheric fate and conversion are of great importance when assessing its environmental impacts. Herein, we report a theoretical kinetic mechanism for the oxidation of hymexazol by OH radicals, as well as the subsequent reactions of its main products with O2 and then with NO by using the Rice-Ramsperger-Kassel-Marcus-based Master equation kinetic model on the potential energy surface explored at the ROCBS-QB3//M06-2X/aug-cc-pVTZ level. The predicted total rate constants ktotal(T, P) for the reaction between hymexazol and OH radicals show excellent agreement with scarcely available experimental values (e.g., 3.6 × 10-12 vs (4.4 ± 0.8) × 10-12 cm3/molecule/s at T = 300 K and P = 760 Torr); thus, the calculated kinetic parameters can be confidently used for modeling/simulation of N-heterocycle-related applications under atmospheric and even combustion conditions. The model shows that 3,4-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-5-yl (IM2), 3,5-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-4-yl (IM3), and (3-hydroxy-1,2-oxazol-5-yl)methyl (P8) are the main primary intermediates, which form the main secondary species of (3,4-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-5-yl)dioxidanyl (IM4), (3,5-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-4-yl)dioxidanyl (IM7), and ([(3-hydroxy-1,2-oxazol-5-yl)methyl]dioxidanyl (IM11), respectively, through the reactions with O2. The main secondary species then can react with NO to form the main tertiary species, namely, (3,4-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-5-yl)oxidanyl (P19), (3,5-dihydroxy-5-methyl-4,5-dihydro-1,2-oxazol-4-yl)oxidanyl (P21), and [(3-hydroxy-1,2-oxazol-5-yl)methyl]oxidanyl (P23), respectively, together with NO2. Besides, hymexazol could be a persistent organic pollutant in the troposphere due to its calculated half-life τ1/2 of 13.7-68.1 h, depending on the altitude.
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  • 文章类型: Journal Article
    自成立以来,使用温度来产生或改变材料,但是用于这种目的的压力超过几十大气压的应用很少被观察到。然而,压力是一个非常有效的热力学变量,越来越多地用于产生新材料或改变现有材料的性质。由于设计用于模拟固态的计算方法通常使用环境压力下的结构数据进行调整,从计算的角度来看,将它们应用于高压问题是对其有效性的高度挑战性测试。然而,使用量子化学计算,通常在密度泛函理论(DFT)的水平上,已经反复被证明是一个伟大的工具,可以用来预测特性,可以在以后被实验者证实,并解释,在分子水平上,高压实验的观察。本文的主要目标是编译,分析,并综合了在承受高压条件的分子晶体中使用DFT的工作结果,以便对这些最新计算提供的可能性进行概述。
    Since its inception, chemistry has been predominated by the use of temperature to generate or change materials, but applications of pressure of more than a few tens of atmospheres for such purposes have been rarely observed. However, pressure is a very effective thermodynamic variable that is increasingly used to generate new materials or alter the properties of existing ones. As computational approaches designed to simulate the solid state are normally tuned using structural data at ambient pressure, applying them to high-pressure issues is a highly challenging test of their validity from a computational standpoint. However, the use of quantum chemical calculations, typically at the level of density functional theory (DFT), has repeatedly been shown to be a great tool that can be used to both predict properties that can be later confirmed by experimenters and to explain, at the molecular level, the observations of high-pressure experiments. This article\'s main goal is to compile, analyze, and synthesize the findings of works addressing the use of DFT in the context of molecular crystals subjected to high-pressure conditions in order to give a general overview of the possibilities offered by these state-of-the-art calculations.
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