Flow field in multilayer gob area, which formed in small hiden-depth, multi-coal layer groups, close distance, hard coal layer, and hard roof, possesses characteristics such as complex, changeable and unstable. Dynami...Flow field in multilayer gob area, which formed in small hiden-depth, multi-coal layer groups, close distance, hard coal layer, and hard roof, possesses characteristics such as complex, changeable and unstable. Dynamic balance theory of local flow field in multilayer gob area was built based on the realistic requirement that the serious threat on current mining coal layer by large-scale spontaneous combustion fire on close spontaneous combustion coal layer group of Datong Coal mining area at the ＇di-hard＇ conditions was caused by small coal pit mining. The kernel was in dynamic balance between flow field pressures of working face and local flow field in multilayer gob area was kept by transformation. Corresponding technology and set of devices were developed.展开更多
By analyzing the process of soil salt accumulation in irrigation area, and discussing the change of irrigation and drainage methods for drought transformed into water, the control scheme of soil secondary salinization...By analyzing the process of soil salt accumulation in irrigation area, and discussing the change of irrigation and drainage methods for drought transformed into water, the control scheme of soil secondary salinization in Wujiazi Irrigation Area was analyzed concretely, and the experience was summarized. After in-depth discussion, the importance of irrigation and drainage methods in the prevention and control of soil secondary salinization in irrigation areas was analyzed.展开更多
Little has been done in measurement and research of the flux of CH4 emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of C...Little has been done in measurement and research of the flux of CH4 emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of CH4 emission flux and to discuss the factors which affect CH4 emission from paddy fields. Experimental paddy fields are chosen using TM pictures respectively in Xinlicheng (43° 49′ N, 125° 20′ E) of the Yitong River’s and in Wanchang (43° 44′ 10″ N, 125° 53′ 11″ E) of the Yinma River’s alluvial plain. The fluxes of CH4 emission from paddy fields are measured by the method of static chamber in Changchun area in 3 consecutive years. The research results show that the peak of CH4 emission from paddy fields occurs during the booting stage. The mean fluxes of CH4 emission are 7.056 mg/(m2· h) and 0.489 mg/(m2· h) in the paddy fields of flood and discontinuous irrigation respectively. The contrastive study holds that climate condition, the way of water management and fertilizer variation have significant influence on fluxes of CH4 emission from paddy fields. The difference of climatic conditions causes the interannual change of the flux of CH4 emission from paddy fields. In general, the flux of CH4 emission from paddy fields of flood irrigation is greater than that from paddy fields of discontinuous irrigation. To change the way of water management perhaps is an available way to reduce CH4 emission flux from paddy fields.展开更多
The health status of 18 sweet corn (Zea mays L. saccharata Sturt) hybrids classified to two types, collected from five areas in China, was examined by PDA method, and factors influencing seed health and relationships ...The health status of 18 sweet corn (Zea mays L. saccharata Sturt) hybrids classified to two types, collected from five areas in China, was examined by PDA method, and factors influencing seed health and relationships between seed health and field seedling emergence were studied. Seventeen fungal genera were isolated and Fusarium was the most frequently isolated. There were significant differences both in incidence of Fusarium and in percentage of infected seeds among 18 hybrids. Research also showed that significant and consistent differences both in seed-borne fungal taxa and in percentage of infected seeds existed between two types of sweet corn. Sugar enhanced corn is more slightly infected than super sweet corn both in fungal taxa (13 and 16, respectively) and in percentage of infected seeds (62.0 and 79.2%, respectively). There were also significant differences both in seed-borne fungal taxa and in percentage of infected seeds among five areas. Seeds from South China were most severely infected, for there were 14 fungal genera detected and the percentage of infected seeds was highly 99.1% while those from Northwest China were slightly infected, for there were 10 fungal genera detected and the percentage of infected seeds was only 14.3%. Further research showed that there were significant negative correlations both between incidence of Fusarium and percentage of field seedling emergence and between percentage of infected seeds and percentage of field seedling emergence. Percentage of field seedling emergence could be estimated by regression equations built by regression analysis.展开更多
Based on the electrical model of body area communication, the change tendency of chan nel gain in 100 kHz 10 MHz band was experimentally analyzed and verified. Results show that chan nel gain was flat and signal a...Based on the electrical model of body area communication, the change tendency of chan nel gain in 100 kHz 10 MHz band was experimentally analyzed and verified. Results show that chan nel gain was flat and signal attenuation was approximately 43 dB in 1 MHz 10 MHz band. The char acteristics of the channel were taken into account in the design of body area spread spectrum com munication and its multiuser receiver issue. BER Eb/No curves of single user and multiuser were de rived by simulation. The characteristics of body area commutation channel were studied and the fea sibility of introducing spread spectrum theory to body area communication was verified.展开更多
[Objective] The research aimed to analyze characteristics of atmospheric electric field in polluted area. [Method] By using data of atmospheric electric field meter in Taiyuan in 2009, daily and annual changes of atmo...[Objective] The research aimed to analyze characteristics of atmospheric electric field in polluted area. [Method] By using data of atmospheric electric field meter in Taiyuan in 2009, daily and annual changes of atmospheric electric field in Taiyuan were analyzed. [ Result] Atmospheric electric field intensity in Taiyuan was higher than that in other areas. Daily change was double-peak double-valley type. The first highest value appeared at nightfall, and the second highest value was before the noon. The first lowest value appeared in early morning, while the second low- est value appeared after the noon. Annual change was single-peak single-valley type. The maximum appeared in winter, while the minimum ap- peared in summer. [ Conclusion] When forecasting thunderstorm, in the area with higher aerosol content, alarm threshold of electric field should be adjusted via comparison with actual observation, which had very strong regional characteristics. By analyzing real-time monitoring data of atmospheric electric field, thunderstorm forecast could be realized, and timeliness and accuracy of warning and forecast could be increased.展开更多
To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as...To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as natural and socio-economic conditions, the control measures of newly increased soil erosion along the project were carried out based on site survey and analysis of relevant information. In addition, adhering to the prin- ciple of partition prevention and treatment, some guiding prevention and control measures of the natural zone passed by the project and soil erosion control district were determined, which provided scientific references and technical support for the rational layout of water and soil conservation and ecological restoration measures in Dina 2 gas field.展开更多
In this paper faults and folds of shirband area (north of damqan) investigated to determine the orient of the stress field. The study area is limited between the two faults with E-W strike and northward slip. Investig...In this paper faults and folds of shirband area (north of damqan) investigated to determine the orient of the stress field. The study area is limited between the two faults with E-W strike and northward slip. Investigations result show major faults of the area have sinisteral mechanism. Waterways displacement and slicken slip of faults approve this issue. Three main folds of area has approx-imately same trend along major faults (E-W). Orientation of stress field investigated and classified by using from some large and medium scale faults and folds. Analysis of stress field investigated by inversion method show that compression axis in the study area have approximately NE-SW strike.展开更多
基金Supported by the Key Projects of the National Natural Science Foundation of China （50834002）
文摘Flow field in multilayer gob area, which formed in small hiden-depth, multi-coal layer groups, close distance, hard coal layer, and hard roof, possesses characteristics such as complex, changeable and unstable. Dynamic balance theory of local flow field in multilayer gob area was built based on the realistic requirement that the serious threat on current mining coal layer by large-scale spontaneous combustion fire on close spontaneous combustion coal layer group of Datong Coal mining area at the ＇di-hard＇ conditions was caused by small coal pit mining. The kernel was in dynamic balance between flow field pressures of working face and local flow field in multilayer gob area was kept by transformation. Corresponding technology and set of devices were developed.
文摘By analyzing the process of soil salt accumulation in irrigation area, and discussing the change of irrigation and drainage methods for drought transformed into water, the control scheme of soil secondary salinization in Wujiazi Irrigation Area was analyzed concretely, and the experience was summarized. After in-depth discussion, the importance of irrigation and drainage methods in the prevention and control of soil secondary salinization in irrigation areas was analyzed.
基金Under the auspices of Jilin Commttee of Science and Technology (grant 963416- 1), and Changchun Jingyuetan Remote Sensing Test
文摘Little has been done in measurement and research of the flux of CH4 emission from paddy fields in Changchun area, Jilin Province, China before 1994. So the purpose of the study is to offer available regional data of CH4 emission flux and to discuss the factors which affect CH4 emission from paddy fields. Experimental paddy fields are chosen using TM pictures respectively in Xinlicheng (43° 49′ N, 125° 20′ E) of the Yitong River’s and in Wanchang (43° 44′ 10″ N, 125° 53′ 11″ E) of the Yinma River’s alluvial plain. The fluxes of CH4 emission from paddy fields are measured by the method of static chamber in Changchun area in 3 consecutive years. The research results show that the peak of CH4 emission from paddy fields occurs during the booting stage. The mean fluxes of CH4 emission are 7.056 mg/(m2· h) and 0.489 mg/(m2· h) in the paddy fields of flood and discontinuous irrigation respectively. The contrastive study holds that climate condition, the way of water management and fertilizer variation have significant influence on fluxes of CH4 emission from paddy fields. The difference of climatic conditions causes the interannual change of the flux of CH4 emission from paddy fields. In general, the flux of CH4 emission from paddy fields of flood irrigation is greater than that from paddy fields of discontinuous irrigation. To change the way of water management perhaps is an available way to reduce CH4 emission flux from paddy fields.
文摘The health status of 18 sweet corn (Zea mays L. saccharata Sturt) hybrids classified to two types, collected from five areas in China, was examined by PDA method, and factors influencing seed health and relationships between seed health and field seedling emergence were studied. Seventeen fungal genera were isolated and Fusarium was the most frequently isolated. There were significant differences both in incidence of Fusarium and in percentage of infected seeds among 18 hybrids. Research also showed that significant and consistent differences both in seed-borne fungal taxa and in percentage of infected seeds existed between two types of sweet corn. Sugar enhanced corn is more slightly infected than super sweet corn both in fungal taxa (13 and 16, respectively) and in percentage of infected seeds (62.0 and 79.2%, respectively). There were also significant differences both in seed-borne fungal taxa and in percentage of infected seeds among five areas. Seeds from South China were most severely infected, for there were 14 fungal genera detected and the percentage of infected seeds was highly 99.1% while those from Northwest China were slightly infected, for there were 10 fungal genera detected and the percentage of infected seeds was only 14.3%. Further research showed that there were significant negative correlations both between incidence of Fusarium and percentage of field seedling emergence and between percentage of infected seeds and percentage of field seedling emergence. Percentage of field seedling emergence could be estimated by regression equations built by regression analysis.
基金Supported by the Ministerial Level Advanced Research Foundation(7130819)
文摘Based on the electrical model of body area communication, the change tendency of chan nel gain in 100 kHz 10 MHz band was experimentally analyzed and verified. Results show that chan nel gain was flat and signal attenuation was approximately 43 dB in 1 MHz 10 MHz band. The char acteristics of the channel were taken into account in the design of body area spread spectrum com munication and its multiuser receiver issue. BER Eb/No curves of single user and multiuser were de rived by simulation. The characteristics of body area commutation channel were studied and the fea sibility of introducing spread spectrum theory to body area communication was verified.
文摘[Objective] The research aimed to analyze characteristics of atmospheric electric field in polluted area. [Method] By using data of atmospheric electric field meter in Taiyuan in 2009, daily and annual changes of atmospheric electric field in Taiyuan were analyzed. [ Result] Atmospheric electric field intensity in Taiyuan was higher than that in other areas. Daily change was double-peak double-valley type. The first highest value appeared at nightfall, and the second highest value was before the noon. The first lowest value appeared in early morning, while the second low- est value appeared after the noon. Annual change was single-peak single-valley type. The maximum appeared in winter, while the minimum ap- peared in summer. [ Conclusion] When forecasting thunderstorm, in the area with higher aerosol content, alarm threshold of electric field should be adjusted via comparison with actual observation, which had very strong regional characteristics. By analyzing real-time monitoring data of atmospheric electric field, thunderstorm forecast could be realized, and timeliness and accuracy of warning and forecast could be increased.
文摘To treat the relationship between project construction and ecological environment and effectively prevent new soil erosion during the construction, according to the project layout, soil erosion distribution as well as natural and socio-economic conditions, the control measures of newly increased soil erosion along the project were carried out based on site survey and analysis of relevant information. In addition, adhering to the prin- ciple of partition prevention and treatment, some guiding prevention and control measures of the natural zone passed by the project and soil erosion control district were determined, which provided scientific references and technical support for the rational layout of water and soil conservation and ecological restoration measures in Dina 2 gas field.
文摘In this paper faults and folds of shirband area (north of damqan) investigated to determine the orient of the stress field. The study area is limited between the two faults with E-W strike and northward slip. Investigations result show major faults of the area have sinisteral mechanism. Waterways displacement and slicken slip of faults approve this issue. Three main folds of area has approx-imately same trend along major faults (E-W). Orientation of stress field investigated and classified by using from some large and medium scale faults and folds. Analysis of stress field investigated by inversion method show that compression axis in the study area have approximately NE-SW strike.
