The effect of magma intrusion on gas outburst is illustrated by a case study of the exposed magma intru- sion in the 313 mining area, upper coal seam Number 3, in the Qiwu Mine located in Shandong province. Vitrinite ...The effect of magma intrusion on gas outburst is illustrated by a case study of the exposed magma intru- sion in the 313 mining area, upper coal seam Number 3, in the Qiwu Mine located in Shandong province. Vitrinite reflectance, mercury injection, and maceral statistical analysis are used to characterize the coal. The aspects of coal metamorphism include changes in micro-components as well as in coal structure, the formation of new substances, and changes in gas absorption and storage. The results show that vitrinite reflectance increases within the region influenced by magma intrusion. The metamorphosed region may be divided into a weakly affected belt, a medium affected belt, a strongly affected belt, and a completely affected belt. Compared to the unaffected coal the total pore volume, as well as the amount of big and middle sized holes, increases while the number of transition holes and micro-pores decreases. This diminishes the absorption capacity of the matrix but enlarges the total gas storage space. Vitrinite con- tent initially decreases slightly but then increases rapidly while the inertinite content increases at first but then decreases. Exinite content decreases, then increases, and finally drops to zero. Higher vitrinite, and a lower inertinite, content increase gas absorption ability. This balances reduced adsorption caused by changes to pore structure. Consequently, gas adsorption capacity is not substantially reduced as the coal rank increases. Thermal metamorphism of the coal produces CH4 and other hydrocarbons that increase the total gas content in the coal seam. Asphaltene migrates into the medium and weakly affected regions filling in the pores and fractures there. This plugs the pathway for gas transport. A barrier is formed that hinders gas flow. C02, H2S, N2, and other gases carried in by the magma react to produce C02, which increases in relative concentration and enhances the risk of gas outburst. The two barriers, magma intrusion on one side and the medium and weakly affected belts on the other, as well as the unaf- fected coal seam itself, trap a large amount of gas during the thermal activity. This is the basic reason for gas outburst. These conclusions can enlighten activities related to gas prevention and control in a low rank coal mine affected by ma^ma intrusion.展开更多
The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on metha...The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the＇square ways show that the better＇average performance was obtainedwith the square way.展开更多
Advertising revenue is generally regarded as the lifeblood of the mass media since it largely contributes to the financial fortunes of both commercial and so-called public media houses. There is a consensus among poli...Advertising revenue is generally regarded as the lifeblood of the mass media since it largely contributes to the financial fortunes of both commercial and so-called public media houses. There is a consensus among political economy scholars that gives advertisers power over media content. It has also been argued that advertisers usually do not associate with ideological enemies. This research therefore sought to find out whether political advertisements especially, during election time, influence media content and whether political advertisers do not associate with media houses they are not ideologically compatible with. During election times, political parties also become big advertisers and newspapers together with broadcasting media compete to get advertisements from political parties so as to boost their financial fortunes. The research focused on the March 29, 2008 Zimbabwe harmonised elections with Network Guardian News a Kwekwe based privately owned community newspaper being used as a case study. This study utilised critical discourse analysis on purposively selected newspaper stories published during the period under study; while in-depth unstructured interviews with editors, reporters from the newspaper and politicians were also conducted to gather information. The findings revealed that in spite of the pro-ZANU-PF Network Guardian News newspaper carrying both MDc and ZANU-PF advertisements, its editorial stance remained hostile to the MDC-T party.展开更多
Since 1865, the scholars from different countries have been studying the Genoese Massari＇s ledger of 1340. The authors have used a fundamentally new approach when studying this famous register. The authors have also ...Since 1865, the scholars from different countries have been studying the Genoese Massari＇s ledger of 1340. The authors have used a fundamentally new approach when studying this famous register. The authors have also analyzed the full-scale financial processes （from registering the expenses of the commune to their coverage by revenue） instead of analyzing some separate transactions which could prove the presence of the double-entry when registering each economic fact. This becomes possible as a result of the reconstruction of medieval entries and registers in the form of a modem account and the construction of the computer model of the whole ledger of 1340. The model of the system is formed according to seven summits of the revenue of the commune, which are distributed upon many factors of registered expenses and united into 17 reporting points. The special attention is paid to the date of the transaction. The authors have found many answers to some questions which were mysteries before. The explanation is given to the sales of goods below the purchasing price and to the exchange of money with significant losses.展开更多
基金jointly supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the National Basic Research Program of China (No. 2009CB219605)the National Natural Science Foundation of China (No. 41072117)
文摘The effect of magma intrusion on gas outburst is illustrated by a case study of the exposed magma intru- sion in the 313 mining area, upper coal seam Number 3, in the Qiwu Mine located in Shandong province. Vitrinite reflectance, mercury injection, and maceral statistical analysis are used to characterize the coal. The aspects of coal metamorphism include changes in micro-components as well as in coal structure, the formation of new substances, and changes in gas absorption and storage. The results show that vitrinite reflectance increases within the region influenced by magma intrusion. The metamorphosed region may be divided into a weakly affected belt, a medium affected belt, a strongly affected belt, and a completely affected belt. Compared to the unaffected coal the total pore volume, as well as the amount of big and middle sized holes, increases while the number of transition holes and micro-pores decreases. This diminishes the absorption capacity of the matrix but enlarges the total gas storage space. Vitrinite con- tent initially decreases slightly but then increases rapidly while the inertinite content increases at first but then decreases. Exinite content decreases, then increases, and finally drops to zero. Higher vitrinite, and a lower inertinite, content increase gas absorption ability. This balances reduced adsorption caused by changes to pore structure. Consequently, gas adsorption capacity is not substantially reduced as the coal rank increases. Thermal metamorphism of the coal produces CH4 and other hydrocarbons that increase the total gas content in the coal seam. Asphaltene migrates into the medium and weakly affected regions filling in the pores and fractures there. This plugs the pathway for gas transport. A barrier is formed that hinders gas flow. C02, H2S, N2, and other gases carried in by the magma react to produce C02, which increases in relative concentration and enhances the risk of gas outburst. The two barriers, magma intrusion on one side and the medium and weakly affected belts on the other, as well as the unaf- fected coal seam itself, trap a large amount of gas during the thermal activity. This is the basic reason for gas outburst. These conclusions can enlighten activities related to gas prevention and control in a low rank coal mine affected by ma^ma intrusion.
基金supported in part by the University of Sétif,and the Ministry of Higher Education and Scientific Research (Algeria) with Project No.E01220080023
文摘The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the＇square ways show that the better＇average performance was obtainedwith the square way.
文摘Advertising revenue is generally regarded as the lifeblood of the mass media since it largely contributes to the financial fortunes of both commercial and so-called public media houses. There is a consensus among political economy scholars that gives advertisers power over media content. It has also been argued that advertisers usually do not associate with ideological enemies. This research therefore sought to find out whether political advertisements especially, during election time, influence media content and whether political advertisers do not associate with media houses they are not ideologically compatible with. During election times, political parties also become big advertisers and newspapers together with broadcasting media compete to get advertisements from political parties so as to boost their financial fortunes. The research focused on the March 29, 2008 Zimbabwe harmonised elections with Network Guardian News a Kwekwe based privately owned community newspaper being used as a case study. This study utilised critical discourse analysis on purposively selected newspaper stories published during the period under study; while in-depth unstructured interviews with editors, reporters from the newspaper and politicians were also conducted to gather information. The findings revealed that in spite of the pro-ZANU-PF Network Guardian News newspaper carrying both MDc and ZANU-PF advertisements, its editorial stance remained hostile to the MDC-T party.
文摘Since 1865, the scholars from different countries have been studying the Genoese Massari＇s ledger of 1340. The authors have used a fundamentally new approach when studying this famous register. The authors have also analyzed the full-scale financial processes （from registering the expenses of the commune to their coverage by revenue） instead of analyzing some separate transactions which could prove the presence of the double-entry when registering each economic fact. This becomes possible as a result of the reconstruction of medieval entries and registers in the form of a modem account and the construction of the computer model of the whole ledger of 1340. The model of the system is formed according to seven summits of the revenue of the commune, which are distributed upon many factors of registered expenses and united into 17 reporting points. The special attention is paid to the date of the transaction. The authors have found many answers to some questions which were mysteries before. The explanation is given to the sales of goods below the purchasing price and to the exchange of money with significant losses.
