Gas adsorption-induced coal swelling is a well- know phenomenon. Coal swelling or shrinkage by adsorption or desorption of water vapor has not been well understood but has significant implications on gas drainage proc...Gas adsorption-induced coal swelling is a well- know phenomenon. Coal swelling or shrinkage by adsorption or desorption of water vapor has not been well understood but has significant implications on gas drainage process for underground coal mining and for primary and enhanced combed methane production. Decreased matrix moisture content leads to coal shrinkage and thus the change of cleat porosity and permeability under reservoir conditions. Unlike gas adsorption in coal which usually forms a single layer of adsorbed molecules, water vapor adsorption in the coal micropores forms multilayer of adsorbed molecules. In this work, a model has been developed to describe the coal swelling strain with respect to the amount of moisture intake by the coal matrix. The model extended an energy balance approach for gas adsorption-induced coal swelling to water vapor adsorption-induced coal swelling, assuming that only the first layer of adsorbed molecules of the multilayer adsorption changes the surface energy, which thus causes coal to swell. The model is applied to describe the experimental swelling strain data measured on an Aus- tralian coal. The results show good agreement between the model and the experimental data.展开更多
To find out the optimum conditions of growth in Scots pine (Pinus sylvestris var. mongolica), we analyzed the radial growth response relationship to climate factors in boreal forests. We present growth response from 3...To find out the optimum conditions of growth in Scots pine (Pinus sylvestris var. mongolica), we analyzed the radial growth response relationship to climate factors in boreal forests. We present growth response from 3-sites Mg (Mangui), KYH (kheyihe), NM (Nanmu) from central Daxing’an mountains. Drought observed in 1920s-1930s years. We analyzed growth response from 1920-2016. Results specified that growth of scots pine did not vary with variation in sites. We measure the influence of vapour pressure and mean maximum and mean minimum diurnal temperature have been shown by correlations of different growing seasons. Most of warm temperature during June to September and growth of Scots pine show a significantly positive increase during winter season. Overall inconsistency in climate conditions of Daxing’an mountains due to Atlantic and Pacific oceans, affects the Asian moon soon and alternatively changes the local temperature and precipitation and vapour pressure and increases the drought severity.展开更多
The bis(N-ethyl-5-methylsalicylaldimine)nickel(II) [Ni(5-me-saletN)2] complex was synthesized and characterized by elemental analyses, FT-IR, TG-DTA, mass spectrometry and vapour pressure measurement studies. The TG c...The bis(N-ethyl-5-methylsalicylaldimine)nickel(II) [Ni(5-me-saletN)2] complex was synthesized and characterized by elemental analyses, FT-IR, TG-DTA, mass spectrometry and vapour pressure measurement studies. The TG curve of the complex showed a single-step weight loss commencing from 490 K to nil residue at 600 K, without competing fragmentation step. The non-isothermal vaporization activation energy value determined by Coats-Redfern method yielded the value of 93.5 ± 7 kJmol–1. The dynamic TG run proved the complex to be completely volatile. And the equilibrium vapour pressure of the complex over the temperature range of 421 - 524 K, determined by the TG-based transpiration technique yielded the value of 94.2 ± 1.2 kJmol–1 for its standard enthalpy of vaporization . The entropy of vaporization was calculated from the intercept and found to be 249.4 ± 2.6 Jmol–1•K–1.展开更多
热物理学一直是物理学的非常重要的分支。随着1869年临界点的发现,显示出了理想气体模型的局限。为解释这一重要物理现象,理论物理学家van der Waals于1873年提出了vander Waals模型,这标志了平均场理论的首次引入。然而,随着实验技术...热物理学一直是物理学的非常重要的分支。随着1869年临界点的发现,显示出了理想气体模型的局限。为解释这一重要物理现象,理论物理学家van der Waals于1873年提出了vander Waals模型,这标志了平均场理论的首次引入。然而,随着实验技术的提高,发现了平均场理论给出的临界指数与实验结果相矛盾。随后引入了与实验一致的普适性与标度假定这两个突破了平均场理论框架的物理概念。这导致了理论物理学家Wilson于1972年提出了临界重整化群理论。目前,基于临界重整化群理论用简单普适的物理数学方法跨接描述流体的经典热力规律与奇异性物理规律,已为国际热物理界所关注。作者在读博士学位期间。展开更多
文摘利用我国70站1999—2003年1月、4月、7月、10月月平均水汽压和能见度资料,反演得到各站大气气溶胶光学厚度(AOD,aerosol optical depth),分析了气溶胶光学厚度的变化特征。结果表明:中国多年平均大气气溶胶光学厚度的分布是以四川盆地为中心向四周减少,长江中下游和广东沿海为两个次大值中心,而东北和西北大部分地区以及云南等地AOD较小;各季节AOD的空间分布都有所不同;近5 a AOD有弱增加趋势;月平均气溶胶光学厚度与能见度有较好的负相关关系。
文摘Gas adsorption-induced coal swelling is a well- know phenomenon. Coal swelling or shrinkage by adsorption or desorption of water vapor has not been well understood but has significant implications on gas drainage process for underground coal mining and for primary and enhanced combed methane production. Decreased matrix moisture content leads to coal shrinkage and thus the change of cleat porosity and permeability under reservoir conditions. Unlike gas adsorption in coal which usually forms a single layer of adsorbed molecules, water vapor adsorption in the coal micropores forms multilayer of adsorbed molecules. In this work, a model has been developed to describe the coal swelling strain with respect to the amount of moisture intake by the coal matrix. The model extended an energy balance approach for gas adsorption-induced coal swelling to water vapor adsorption-induced coal swelling, assuming that only the first layer of adsorbed molecules of the multilayer adsorption changes the surface energy, which thus causes coal to swell. The model is applied to describe the experimental swelling strain data measured on an Aus- tralian coal. The results show good agreement between the model and the experimental data.
文摘To find out the optimum conditions of growth in Scots pine (Pinus sylvestris var. mongolica), we analyzed the radial growth response relationship to climate factors in boreal forests. We present growth response from 3-sites Mg (Mangui), KYH (kheyihe), NM (Nanmu) from central Daxing’an mountains. Drought observed in 1920s-1930s years. We analyzed growth response from 1920-2016. Results specified that growth of scots pine did not vary with variation in sites. We measure the influence of vapour pressure and mean maximum and mean minimum diurnal temperature have been shown by correlations of different growing seasons. Most of warm temperature during June to September and growth of Scots pine show a significantly positive increase during winter season. Overall inconsistency in climate conditions of Daxing’an mountains due to Atlantic and Pacific oceans, affects the Asian moon soon and alternatively changes the local temperature and precipitation and vapour pressure and increases the drought severity.
文摘The bis(N-ethyl-5-methylsalicylaldimine)nickel(II) [Ni(5-me-saletN)2] complex was synthesized and characterized by elemental analyses, FT-IR, TG-DTA, mass spectrometry and vapour pressure measurement studies. The TG curve of the complex showed a single-step weight loss commencing from 490 K to nil residue at 600 K, without competing fragmentation step. The non-isothermal vaporization activation energy value determined by Coats-Redfern method yielded the value of 93.5 ± 7 kJmol–1. The dynamic TG run proved the complex to be completely volatile. And the equilibrium vapour pressure of the complex over the temperature range of 421 - 524 K, determined by the TG-based transpiration technique yielded the value of 94.2 ± 1.2 kJmol–1 for its standard enthalpy of vaporization . The entropy of vaporization was calculated from the intercept and found to be 249.4 ± 2.6 Jmol–1•K–1.
文摘热物理学一直是物理学的非常重要的分支。随着1869年临界点的发现,显示出了理想气体模型的局限。为解释这一重要物理现象,理论物理学家van der Waals于1873年提出了vander Waals模型,这标志了平均场理论的首次引入。然而,随着实验技术的提高,发现了平均场理论给出的临界指数与实验结果相矛盾。随后引入了与实验一致的普适性与标度假定这两个突破了平均场理论框架的物理概念。这导致了理论物理学家Wilson于1972年提出了临界重整化群理论。目前,基于临界重整化群理论用简单普适的物理数学方法跨接描述流体的经典热力规律与奇异性物理规律,已为国际热物理界所关注。作者在读博士学位期间。
