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从吹律听风到候气应律 被引量:2
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作者 薛冬艳 《南京艺术学院学报(音乐与表演版)》 2018年第3期5-10,共6页
本文考察汉代候气法源流,梳理其与先秦吹律传统的关联。先秦至汉的天文历法合同音律状况,有着从候风转向候气的一个漫长过渡期,即从吹律听风到候气应律。两者的转折在于由四时八节的纪年方法转向十二月历的纪年方法,由听辨风向、风力转... 本文考察汉代候气法源流,梳理其与先秦吹律传统的关联。先秦至汉的天文历法合同音律状况,有着从候风转向候气的一个漫长过渡期,即从吹律听风到候气应律。两者的转折在于由四时八节的纪年方法转向十二月历的纪年方法,由听辨风向、风力转向观测地气。通过与天文学、物理学、易学的比照,推断出候气应律并非单纯的定律制历的操作方法,而是联系了天体运行、物候占卜、数算推步、物理实验等因素的复合型定律法问题,并总结了引发候气的原因和影响候气准确率的因素来自于节气、闰法、岁差、地理、操作技术等条件的制约。从思想意识而言,先秦有机宇宙观至两汉元气论思想的演变,也是使测度时间、气候的规则从风律转向律气的原因。 展开更多
关键词 律气
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楔形孔板流量计内多气泡的运动行为 被引量:3
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作者 张一夫 李维仲 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2012年第6期814-817,共4页
针对楔形孔板流量计多个气泡的运动,建立了对孔板流量计内气液两相流动的数学模型.采用贴体坐标系下同位网格的SIMPLE算法解决速度与压力的耦合问题.利用贴体坐标下Level Set方法追踪两相界面的运动.通过模拟结果中节流截面含气律变化... 针对楔形孔板流量计多个气泡的运动,建立了对孔板流量计内气液两相流动的数学模型.采用贴体坐标系下同位网格的SIMPLE算法解决速度与压力的耦合问题.利用贴体坐标下Level Set方法追踪两相界面的运动.通过模拟结果中节流截面含气律变化的分析,得出混相密度变化才是影响楔形孔板流量计测量精度的主要因素.因此,校正多相流的混相密度值是提高孔板流量计的测量精度,减小测量误差的最佳方法. 展开更多
关键词 楔形孔板流量计 贴体坐标系 LEVEL SET方法 SIMPLE算法 节流截面含 混相密度
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《周易》乐舞思想及其对中国乐舞的影响 被引量:3
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作者 陈碧 《中国文学研究》 CSSCI 北大核心 2006年第3期31-34,共4页
《周易》中的乐舞思想十分丰富,《需卦》、《豫卦》、《文言》、《系辞》和《杂卦》等多处涉及“乐”,《离卦》、《中孚》涉及“歌”,《系辞上》涉及“舞”,《渐卦》蹁跹启文舞,《夬卦》干戚发武舞。《周易》“阴阳”、“天地”、“律... 《周易》中的乐舞思想十分丰富,《需卦》、《豫卦》、《文言》、《系辞》和《杂卦》等多处涉及“乐”,《离卦》、《中孚》涉及“歌”,《系辞上》涉及“舞”,《渐卦》蹁跹启文舞,《夬卦》干戚发武舞。《周易》“阴阳”、“天地”、“律”、“同”等概念对中国乐舞理论、表演起到潜移默化的作用,音乐典籍《礼记.乐记》就深受其影响。中国艺术和《周易》象数理有着密切关系。 展开更多
关键词 阴阳 律气
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Influence of Climate and Daylength on the Activity Budgets of Feral Goats (Capra hircus) on the Isle of Rum, Scotland 被引量:5
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作者 石建斌 Robin Dunbar +1 位作者 李迪强 肖文发 《Zoological Research》 CAS CSCD 北大核心 2006年第6期561-568,共8页
Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainf... Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainfall) and seasonal variations in daylength on daytime activity budgets. This study showed that the percentage of daytime spent in feeding by feral goats on Rum Island decreased with average monthly temperature, while the percentage of daytime spent in lying increased and rainfall had no significant effects on the percentage daytime spent in feeding or lying. The daylength varied greatly from January to December with the longest daylength being in June and July, and the shortest one in December and January. The amount of daytime spent feeding decreased from summer to winter, although the percentage of daytime spent feeding increased greatly from summer to winter. The seasonal variations in daylength seem to be an important factor in constraining feral goats' activity, especially in the cold and wet winters when forage biomass and quality are both at their lowest level. We discuss the influence of such constraining effects on the forage intake of these goats and their winter survival rate, as well as its implication for population regulation of these goats. 展开更多
关键词 WEATHER Activity budget DAYLENGTH Feral goat Rum Island
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Species and Occurrence of Scarab in Sweet Potato Growing Areas of Xuzhou,Jiangsu
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作者 闫会 薛程 +2 位作者 张允刚 马代夫 李强 《Agricultural Science & Technology》 CAS 2015年第12期2742-2745,共4页
Frequency-vibrancy pest-killing lamp was used to calculate the numbers and types of scarabs during the growing period of sweet potato in Xuzhou area, thus to study the occurrence regularity of scarab and effect of met... Frequency-vibrancy pest-killing lamp was used to calculate the numbers and types of scarabs during the growing period of sweet potato in Xuzhou area, thus to study the occurrence regularity of scarab and effect of meteorological factor on its occurrence, which provided a reference and guidance for the control of grub in sweet potato field. The monitoring results indicated that scarabs in sweet potato planting area of Xuzhou mainly included Anomala corpulenta, Holotrichia parallela Motschulsky, Maladera verticalis and Holotrichia trichophora Fairm. Holotrichia tri- chophora Fairm has entered into its late stage at the early cultivation stage of sweet potato with a few occurrence quantities. The elongation stage of sweet potato vine is the full incidence period of imagoes of Maladera verticalis and Anomala cor- pulenta. Full incidence period of Holotrichia parallela Motschulsky is from late June to middle August, the outbreak cycle of which is long. The unearthed imagoes fol- low the regular change "many-few-many-few". Effects of meteorological factor on the activities of various scarabs are different. The activities of various scarabs are fre- quent in warm and windless sunny days. In rainy days, Holotrichia parallela Motschulsky, Holotrichia trichophora Fairm and Maladera verticalis are inactive. The numbers of Anomala corpulenta in cloudy days but not rainy days are higher than that in sunny days. 展开更多
关键词 Sweet potato SCARAB Occurrence regularity Meteorological factor
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以气论乐 以律论天——气论哲学视域下的汉代乐律思想辨析
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作者 孙小迪 《中国音乐》 CSSCI 北大核心 2021年第5期200-208,共9页
"气"是中国思想史的重要概念。它贯穿于汉代构建的"天人合一"的宇宙论体系之中。追述"气"概念在汉代天人哲学体系中作为一个充满活力的思辨范畴的变迁,有助于展开对汉代乐律思想的考究。研究表明:气在《... "气"是中国思想史的重要概念。它贯穿于汉代构建的"天人合一"的宇宙论体系之中。追述"气"概念在汉代天人哲学体系中作为一个充满活力的思辨范畴的变迁,有助于展开对汉代乐律思想的考究。研究表明:气在《周易》体系中,称为卦气;气之于日月星辰的天文学体系,称为节气和候气;气之于十二律管的乐律学体系,称为律气。汉代是这种关联的滥觞时期,气的概念和范畴在汉代被演绎成为无所不包的介质。由于气论哲学以"运数"(度量)的数量关系来归纳类比范畴及事物发展的规律,所以,在汉代,出现了天数、历数、术数、律数的综合与同一。采用"以气论乐,以律论天"这一哲学视角,可以进一步理解汉代乐律思想体系如何构建及其学术源流等问题。 展开更多
关键词 律气
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Approach to increasing the quality of pressure-relieved gas drained from protected coal seam using surface borehole and its industrial application 被引量:14
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作者 Yingke Liu Fubao Zhou +1 位作者 Jianlong Wang Jun Liu 《International Journal of Coal Science & Technology》 EI 2015年第1期46-51,共6页
During mining of lower protective coal seam, a surface borehole can efficiently extract not only the pressure-relieved gas from the protected layer, but also the gas from the mining layer gob. If the distance between ... During mining of lower protective coal seam, a surface borehole can efficiently extract not only the pressure-relieved gas from the protected layer, but also the gas from the mining layer gob. If the distance between the borehole and gob is too large, the quantity of gas drained from the protected layer decreases substantially. To solve this problem, a mathematical model for extracting pressure-relieved gas from a protected coal seam using a surface borehole was established, based on the radial gas flow theory and law of conservation of energy. The key factors influencing the quantity of gas and the drainage flow network using a surface borehole were presented. The results show that the quantity of pressure-relieved gas drained from the protected layer can be significantly increased by increasing the flow resistance of the borehole bottom. Application of this method in the Wulan Coal Mine of the Shenhua Group significantly increased the flow of pure gas and the gas concentration (by factors of 1.8 and 2.0, respectively), thus demonstrating the remarkable effects of this method. 展开更多
关键词 Surface borehole Gas drainage Borehole bottom resistance Pressure-relieved gas
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Enantioselective Determination of R-(-)-and S-(+)-Mexiletine in Microsomal Incubates by Capillary gas Chromatography
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作者 王似菊 毛海琼 曾苏 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第4期34-37,共4页
A method for the assay of R ( ) and S (+) mexiletine in rat liver microsomal incubates was developed. The method involved extraction of mexiletine from the microsomal incubates, and formation of mexiletine diast... A method for the assay of R ( ) and S (+) mexiletine in rat liver microsomal incubates was developed. The method involved extraction of mexiletine from the microsomal incubates, and formation of mexiletine diastereomeric derivatives with a chiral reagent S ( ) N trifluoroacetyl prolyl chloride. Separation and quantitation of the diastereomeric mexiletine derivatives were carried out by a capillary gas chromatographic system with flame ionization detection. The assay was linear from 5 to 500 μg/ml for each enantiomer. The average recoveries of analytical method were 93 31±5 59% and 93 10±5 11% for R ( ) and S (+) mexiletine, respectively. The limits of detection and quantitation for the method were 1 0 μg/ml and 5 0 μg/ml for the R ( ) and S (+) mexiletine isomers, respectively. The reproducibility in the assay was better than 16.5% (RSD). The method has been applied to the metabolism study of R ( ) and S (+) mexiletine in rat liver microsomal incubates. 展开更多
关键词 MEXILETINE Capillary gas chromatography Enantiomer separation
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有关北宋徽宗代的正声与中声研究 被引量:1
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作者 郑花顺 徐海准 《黄钟(武汉音乐学院学报)》 CSSCI 北大核心 2011年第4期168-175,183,共9页
在韩国音乐史中首次提到正声与中声的文献史料为《高丽史.乐志》。其中记载,正声与中声的出现始于北宋徽宗时期的大晟雅乐,原是指音高不同的两种音乐或者乐器,但韩国音乐学界所探讨的大晟雅乐正声与中声是按照钟磬(编钟和编磬)的数量(16... 在韩国音乐史中首次提到正声与中声的文献史料为《高丽史.乐志》。其中记载,正声与中声的出现始于北宋徽宗时期的大晟雅乐,原是指音高不同的两种音乐或者乐器,但韩国音乐学界所探讨的大晟雅乐正声与中声是按照钟磬(编钟和编磬)的数量(16和12)来分的,并且仅关注了有关音域方面的问题。因此,为了正确的了解有关韩国音乐史中所出现的正声与中声,文章拟对北宋徽宗时期的大晟雅乐中出现的正声与中声进行考察。 展开更多
关键词 正声 中声 大晟雅乐 魏汉津乐
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Oxidation kinetics regularity in spontaneous combustion of gas coal 被引量:13
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作者 WANG Lanyun JIANG Shuguang +4 位作者 WU Zhengyan SHAO Hao ZHANG Weiqing CHEN Yueqin ZOU Lili 《Mining Science and Technology》 EI CAS 2010年第1期59-63,共5页
In order to investigate the oxidation kinetics of gas coal at low temperatures, we derived a rate equation of oxygen consumption during low-temperature oxidation of gas coal and deduced an E-c equation, expressing the... In order to investigate the oxidation kinetics of gas coal at low temperatures, we derived a rate equation of oxygen consumption during low-temperature oxidation of gas coal and deduced an E-c equation, expressing the relation between active energy E and oxygen concentration c. The reaction order n and active energy E were calculated with this equation based on experiments of static oxygen consumption tests. In addition, we proved the rationality of the E-c equation using a kinetic compensation effect and obtained the isokinetic temperature Tc. The results show that: 1) the gas coal oxidizes easily with increasing temperature and the oxidation tends to be spontaneous at higher temperatures; 2) the oxygen concentration c affects oxygen consumption very much at lower temperatures but has only a small effect at higher temperatures; 3) the isokinetic temperature Tc was 127 ℃ which has been experimentally validated as the key turning point during low-temperature spontaneous combustion of gas coal. 展开更多
关键词 static oxygen consumption test system reaction order active energy kinetic compensation effect isokinetic temperature
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Research on the gas desorption law of the consumingly destruct coal 被引量:3
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作者 陈向军 王兆丰 +1 位作者 杨宏民 肖东辉 《Journal of Coal Science & Engineering(China)》 2008年第2期263-266,共4页
To solve the issues of calculating gas loss quantity during sampling,simulated gas desorption process of the consumingly destruct coal with the assembly simulation testing device.Through an analysis of the simulation ... To solve the issues of calculating gas loss quantity during sampling,simulated gas desorption process of the consumingly destruct coal with the assembly simulation testing device.Through an analysis of the simulation test datum using SPSS software, established a new formula that can be better description on gas desorption process,more accurate calculation of the gas loss quantity during sampling process,and calculating re- leasable gas quantity during a certain period.Aimed at the new formula,the best time of taking sample is confirmed 3 minutes for consumingly destruct coal,the computative error is less than 10%.Through experiment at laboratory and locale,the new formula could well describe consumingly destruct coal gas desorption law,and it has high calculation preci- sion of gas loss quantity in sampling and desorption quanlity. 展开更多
关键词 gas desorption law consumingly destruct coal lost gas quantity ERROR
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Study on law of raw coal seepage during loading process at different gas pressures 被引量:9
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作者 Meng Junqing Nie Baisheng +1 位作者 Zhao Bi Ma Yechao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第1期31-35,共5页
In order to reveal the law of raw coal seepage at different gas pressures, the gravity constant load seepage experimental system was developed and used. The law of raw coal seepage at different gas pressures with He, ... In order to reveal the law of raw coal seepage at different gas pressures, the gravity constant load seepage experimental system was developed and used. The law of raw coal seepage at different gas pressures with He, N2 and CO2 was investigated. The results show that, in a given state of stress during the experiment, with the increase of gas pressure, the permeability of raw coal sample prone to outburst exhibits a significantly decrease, and then exhibits an increasing trend when reaching the extreme point. The law of Klingberg coefficient related to the stress state and the gas adsorption properties was also obtained. Under the same experimental conditions, the Klingberg coefficient of He is greater than that of N2; and the Klingberg coefficient of CO2 has minimum value; so the stronger the gas adsorption is, the smaller the Klingberg coefficient of gas goes. Klinkenberg coefficient decreases with the increase of effective stress. Under the same conditions, the permeability of He is greater than that of N2; the permeability of CO2 has minimum value; so the stronger the gas adsorption is, the lower the permeability of the coal sample goes. The results have important significance in revealing the mechanism of gas seenage. Dredicting coal mine gas disaster, and gas drainage and safety nroduction. 展开更多
关键词 Raw coalPermeabilityStressglinkenberg effectAdsorption
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Analytical solution of coal-bed methane migration with slippage effects in hypotonic reservoir 被引量:1
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作者 XIAO Xiao-chun PAN Yi-shan YU Li-yan JIANG Chun-yu 《Journal of Coal Science & Engineering(China)》 2011年第2期137-141,共5页
Using theoretical analysis, the single-phase gas seepage mathematical model influenced by slippage effects was established. The results show that the pressure of producing wells attenuates more violently than the well... Using theoretical analysis, the single-phase gas seepage mathematical model influenced by slippage effects was established. The results show that the pressure of producing wells attenuates more violently than the wells without slippage effects. The decay rate of reservoir pressure is more violent as the Klinkenherg factor increases. The gas prediction output gradually increases as the Klinenberg factor increases when considering gas slippage effects. Through specific examples, analyzed the law of stope pore pressure and gas output forecast changing in a hypotonic reservoir with slippage effects. The results have great theoretical significance in the study of the law of coal-bed methane migration in hypotonic reservoirs and for the exploitation of coal-bed methane. 展开更多
关键词 slippage effect hypotonic reservoir Klinkenberg factor analysis solution
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Conformation and Orientation of Phospholipid Molecule in Pure Phospholipid Monolayer During Compressing
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作者 XUE Weilan WANG Dan ZENG Zuoxiang GAO Xuechao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第2期177-184,共8页
On the basis of energy conservation law and surface pressure isotherm, the conformation energy changes of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) in pure phospholipid rnono... On the basis of energy conservation law and surface pressure isotherm, the conformation energy changes of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG) in pure phospholipid rnonolayer at the air/water interface during compression are derived. The optimized conformations of phospholipids at absolute freedom state are simulated by Gaussian 98 software. Based on following assumptions: (1) the conformation energy change is mainly caused by the rotation of one special bond; (2) the atoms of glycerol near the water surface are active; (3) the rotation is motivated by hydrogen-bond action; (4) the rotation of bond is inertial, one simplified track of conformational change is suggested and the conformations of DPPC and DPPG at different states are determined by the plots of conformation energy change vs. dihedral angle. The thickness of the simulated phospholipid monolayer is consistent with published experimental result. According to molecular areas at different states, the molecular orientations in the compressing process are also developed. 展开更多
关键词 DIPALMITOYLPHOSPHATIDYLCHOLINE dipalmitoylphosphatidylglycerol phospholipid monolayer CONFORMATION ORIENTATION
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Seepage laws of two kinds of disastrous gas in complete stress-strain process of coal 被引量:2
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作者 Cao Shugang Guo Ping Zhang Zunguo Li Yi Wang Yong 《Mining Science and Technology》 EI CAS 2011年第6期851-856,共6页
The similarities and differences in seepage flow evolution laws of CH4 and CO2 during complete stress- strain process of samples were comparatively analyzed. The results show that the seepage flow evolution laws of CH... The similarities and differences in seepage flow evolution laws of CH4 and CO2 during complete stress- strain process of samples were comparatively analyzed. The results show that the seepage flow evolution laws of CH4 and CO2 are extremely similar during the stress-strain process, showing that the character- istic first decreased and then increased. A mathematical model was also established according to the rela- tionship of seepage velocity and axial strain. However, due to the strong adsorption ability of CO2, the coal samples generated a more serious ''Klinkenberg effect'' under the condition of CO2. Owing to this, the CO2 seepage flow resulted into occurrence of ''stagnation'' phenomenon during the late linear elastic stage II. In the strain consolidation stage III, the increment rate of CH4 seepage velocity was significantly greater than that of CO2. In the stress descent stage IV, when the axial load reached the peak pressure of coal, the increment rates of CH4 seepage velocity presented a turning point. But the changing rate of CO2 seepage velocity still remained slow and a turning point was presented at one time after the peak of thestrain pressure, which showed an obvious feature of hysteresis. 展开更多
关键词 Outburst coal CH4 CO2 Klinkenberg effect Complete stress–strain
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Propagation law of shock waves and gas flow in cross roadway caused by coal and gas outburst 被引量:17
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作者 Zhou Aitao Wang Kai Wu Zeqi 《International Journal of Mining Science and Technology》 SCIE EI 2014年第1期23-29,共7页
In order to study the propagation law of shock waves and gas flow during coal and gas outburst,we analyzed the formation process of outburst shock waves and gas flow and established the numerical simulation models of ... In order to study the propagation law of shock waves and gas flow during coal and gas outburst,we analyzed the formation process of outburst shock waves and gas flow and established the numerical simulation models of the roadways with 45°intersection and 135°intersection to simulate the propagation of outburst gas flow and the process of gas transport.Based on the analysis of the simulation results,we obtained the qualitative and quantitative conclusions on the characteristics and patterns of propagation and attenuation of outburst shock waves and gas flow.With the experimental models,we investigated the outburst shock waves and gas flow in the roadways with the similar structures to the simulated ones.According to the simulation results,when the angle between the driving roadway and the adjacent roadway increased,the sudden pressure variation range in adjacent roadway and the influencing scope of gas flow increased and the sudden pressure variation duration decreased.The intersection between the driving roadway and the adjacent roadway has no effect on airflow reversal induced by the shock waves and gas flow. 展开更多
关键词 Coal and gas outburst Shock waves and gas flow Propagation law Cross roadway
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Rules of variation in hydrogen during reignition of underground fire zones of spontaneous coal combustion 被引量:4
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作者 ZHOU Fubao LI Jinhai LIU Yusheng SHAO He 《Mining Science and Technology》 EI CAS 2010年第4期499-503,共5页
In light of the possibility of reignition when unsealing the closed fire zones, the occurrence of reignition was simulated by a home-made experimental device, hydrogen variety rule from combustion to unsealing was ana... In light of the possibility of reignition when unsealing the closed fire zones, the occurrence of reignition was simulated by a home-made experimental device, hydrogen variety rule from combustion to unsealing was analyzed, the three-stage generation model of hydrogen during reignition in fire zone was put forward and the probability that hydrogen was taken as an indicator gas was discussed. The results show that: when fire zone is ready to unseal, which is filled with hydrogen at a high concentration, it is more prone to reignite. 展开更多
关键词 unsealing fire zone REIGNITION HYDROGEN generation model indicator gas
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Executive Compensation: Is It Right?
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作者 Elizabeth Enow Foma 《Journal of Modern Accounting and Auditing》 2012年第12期1873-1878,共6页
Issues are arising regarding the large amount of money provided to top executives in many compames tor Uaetr bonuses and incentives. These huge amounts for executive compensation are being questioned in comparison to ... Issues are arising regarding the large amount of money provided to top executives in many compames tor Uaetr bonuses and incentives. These huge amounts for executive compensation are being questioned in comparison to the dividends received by stockholders. Four companies are analyzed: Citigroup, Starbucks, General Electric (GE), and Kraft Foods. Present issues faced by Citigroup show that the company's provision in their executive compensation is not acceptable, On the other hand, Starbucks, GE, and Kraft Foods are the companies that follow legal rules provided by the Securities and Exchange Commission (SEC) in providing compensations to executives. Thus, they are good exemplars to other companies. 展开更多
关键词 EXECUTIVE stockholders COMPENSATION bonuses INCENTIVES
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Numerical simulation study of gob air leakage field and gas migration regularity in downlink ventilation 被引量:4
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作者 ZHANG Jian-rang WANG Chun-qiao DONG Ding-wen 《Journal of Coal Science & Engineering(China)》 2011年第3期316-320,共5页
Aiming at the issue that mass of gas emission from mining gob and the gas exceeded in working face, gob air leakage field and gas migration regularity in downlink ventilation was studied. In consideration of the influ... Aiming at the issue that mass of gas emission from mining gob and the gas exceeded in working face, gob air leakage field and gas migration regularity in downlink ventilation was studied. In consideration of the influence of natural wind pressure to analyze the stope face differential pressure, gob air leakage field distribution and gas migration regularity theoretically. Established a two-dimensional physical model with one source and one doab, and applied computational fluid dynamics analysis software Fluent to do numerical simulation, analyzed and contrasted to the areas of gob air leakage on size and gas emission from gob to working face on strength when using the downlink ventilation and uplink ventilation. When applied downward ventilation in stope face, the air leakage field of gob nearly working face, and the air leakage intensity were smaller than uplink, this can effectively reduce the gas emission from gob to working face; when used downlink ventilation, the air leakage airflow carry the lower amount of gas to doab than uplink ventilation, and more easily to mix the gas, reduced the possibility of gas accumulation in upper comer and the stratified flows, it can provide protection to mine with safe and effective production. 展开更多
关键词 downlink ventilation natural wind pressure air leakage field gas migration numerical simulation
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Studies on the Analytical Method for a New Antiarrhythmic Guanfu Base A in Rabbit Plasma
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作者 杨丽莉 杨巷菁 +2 位作者 刘静涵 李耐三 邱宁婴 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第1期51-59,共9页
Guan-fu base A(GFA),a new antiarrhythmic alkaloid with a structure of C_(20)-diterpenoid could react rapidly and quantitatively with trifluoroacetic anhydride(TFAA) to produce GFA—TFAA of which the structure was iden... Guan-fu base A(GFA),a new antiarrhythmic alkaloid with a structure of C_(20)-diterpenoid could react rapidly and quantitatively with trifluoroacetic anhydride(TFAA) to produce GFA—TFAA of which the structure was identified by GC—MSD.There was a wide linear range of the GC-ECD method from 10 to 20000ng/ml(r=0.9984).The average recovery of GFA from the spiked plasma was 97.52%.The coefficients of variation of within-day and between-day were less than 7% and 9%,respectively.The method was used in the preclinical experiment of pharmacology of GFA and the results showed that GFA con- centrations in rabbits' plasma within 6 hours after the administration ranged from 0.338± 0.014 to 13.459±5.393μg/ml for dosage 10mg/kg,from 0.133±0.038 to 2.546±0.480 μg/ml for dosage 2mg/kg and from 45.25±10.34 to 535.86±24.36ng/ml for dosage 0.4 mg/kg. 展开更多
关键词 Guan-fu base A (GFA) GC-ECD Trifluoroacetic anhydride(TFAA) DERIVATIZATION Plasma concentration
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