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Articles 91 - 120 of 1656
Full-Text Articles in Earth Sciences
Managing Seed Dormancy In Forage Legumes And Grasses: An Update, Yanrong Wang, Xiaowen Hu
Managing Seed Dormancy In Forage Legumes And Grasses: An Update, Yanrong Wang, Xiaowen Hu
IGC Proceedings (1977-2023)
Seed dormancy is a common feature of the majority of forage species. It usually causes problems both to the grower and the seed analyst. Many methods have been developed to break dormant seed over the time, and efficacy of a method usually varies with species and cultivars. The objective of this paper is to review and summarise important methods used for seed dormancy breaking in forage legume and grass species, and the mechanisms involved.
Restoring North America’S Sagebrush Steppe Ecosystem Using Seed Enhancement Technologies, Matthew D. Madsen, Kirk W. Davies, Chad S. Boyd, Jay D. Kerby, Daniel L. Carter, Tony J. Svejcar
Restoring North America’S Sagebrush Steppe Ecosystem Using Seed Enhancement Technologies, Matthew D. Madsen, Kirk W. Davies, Chad S. Boyd, Jay D. Kerby, Daniel L. Carter, Tony J. Svejcar
IGC Proceedings (1977-2023)
Rangelands occupy over a third of global land area, and in many cases are in less than optimum condition as a result of past land use, catastrophic wildfire and other disturbance, invasive species, or climate change. Often the only means of restoring these lands involves seeding desirable species, yet there are few cost effective seeding technologies, especially for the more arid rangeland types. The inability to consistently establish desired plants from seed may indicate that the seeding technologies being used are not successful in addressing the primary sources of mortality in the progression from seed to established plant. Seed enhancement …
Comprehensive Evaluation Of Wild Elymus L. Germplasm In Inner Mongolia, Juan Qi, Wen-Xia Cao, Ting Jiao, Xiao-Peng Pu, Wei-Hong Yan
Comprehensive Evaluation Of Wild Elymus L. Germplasm In Inner Mongolia, Juan Qi, Wen-Xia Cao, Ting Jiao, Xiao-Peng Pu, Wei-Hong Yan
IGC Proceedings (1977-2023)
Grassland degradation is increasing in severity and is an important global issue in the 21st century. Increasing research is being conducted on how to solve these problems (Niu and Jiang 2004). Restoration and revegetation of degraded grassland and the establishment of artificial pastures are important in addressing degradation. Successful restoration requires the identification of species and seed sources that are adapted to the ecological conditions of the restoration site. Elymus L. is a large genus that contains about 150 species distributed across a wide range of ecological sites across temperate and subtropical regions of the world (Dewey 1984; Love 1984). …
Fatty Acid Analysis Of The Transgenic Tobacco Expressing A Delta 6-Desaturase Gene From Microula Sikkimensis, Shujuan Wu, Lijing Zhang, Xiaolong Chen, Xiumei Miao, Decao Niu, Hua Fu
Fatty Acid Analysis Of The Transgenic Tobacco Expressing A Delta 6-Desaturase Gene From Microula Sikkimensis, Shujuan Wu, Lijing Zhang, Xiaolong Chen, Xiumei Miao, Decao Niu, Hua Fu
IGC Proceedings (1977-2023)
γ-Linolenic acid (GLA, 18:3Δ6, 9, 12) and octadecatetraenoic acid (OTA, 18:4Δ6, 9, 12, 15) are important polyunsaturated fatty acids (PUFAs), which have been proved to be benefit for human health (Fan and Chapkin 1998; Whelan 2009). Currently, fish are the predominant source of PUFAs. However, with the growth of world’s population and the more nutrition requirements, fishery resources are shrinking. Alternative sources of PUFAs are being investigated (Truksa et al. 2009). The major oil crops do not contain GLA and OTA, only several plant species contain these important fatty acids in their leaf lipids and …
Production Of Giant Panicum In Contrasting Environments In Semi-Arid Kenya, Donald M. G. Njarui, Mwangi Gatheru, David Miano Mwangi, George A. Keya
Production Of Giant Panicum In Contrasting Environments In Semi-Arid Kenya, Donald M. G. Njarui, Mwangi Gatheru, David Miano Mwangi, George A. Keya
IGC Proceedings (1977-2023)
Giant panicum (Panicum maximum Jacq.) is a tall, vigorous perennial grass that is native to tropical and sub-tropical Africa. It is drought tolerant due to its deep and dense fibrous roots system and grows in a wide range of soil types. It is an important livestock feed and has been extensively cultivated in Brazil (Santos et al. 2006). Despite its wide genetic diversity in East Africa, its potential for livestock feed has not been exploited there due to limited research. Our research was aimed at evaluating the production of several giant panicum ecotypes in contrasting environments in semi-arid …
Controlling Lethal Browning Of Hemarthria Compressa Tissue Cultures, Chunhua Yang, Yaohua Xu, Lingzhi Chen, Yifang Sui
Controlling Lethal Browning Of Hemarthria Compressa Tissue Cultures, Chunhua Yang, Yaohua Xu, Lingzhi Chen, Yifang Sui
IGC Proceedings (1977-2023)
Hemarthria compressa is an important warm-season forage grass for use in Southwest China. However, due to poor seed set, it is propagated by vegetative cuttings of stolons, rhizomes, and nodal sections. The in vitro propagation of H. compressa is still faced with difficulties including blackening or browning of tissues prior to culturing due to the oxidation of phenolic compounds by polyphenolic oxidase enzyme present in excised tissue (Yang et al. 2008). The objectives of the study were to investigate possible means of successful initiation of cultures through elimination of phenolic browning.
Leaf Growth And Senescence Rates In Brown-Back Wallaby Grass, Rytidosperma Duttonianum, Helen G. Daily, Shaun Lisson, Kerry L. Bridle, Peter A. Lane, Stuart Anderson, Ross Corkrey
Leaf Growth And Senescence Rates In Brown-Back Wallaby Grass, Rytidosperma Duttonianum, Helen G. Daily, Shaun Lisson, Kerry L. Bridle, Peter A. Lane, Stuart Anderson, Ross Corkrey
IGC Proceedings (1977-2023)
Knowledge of leaf turnover in grasses is necessary to model curing (the accumulation of dead material in the sward), which is not well represented in current pasture growth models, nor for many Australian native species. Leaf turnover begins with the appearance of successive leaves, which elongate until typically, a leaf ligule develops to indicate a mature, fully expanded length. Green leaf life span extends from appearance to the beginning of senescence, which ultimately leads to death (Fig. 1). Here, the individual rates of leaf growth and senescence for the Australian native brown-back wallaby grass, Rytidosperma duttonianum (Cashmore) Connor & Edgar, …
Basin Wildrye (Leymus Cinereus) Pooled Tetraploid Accessions For U.S. Intermountain West Rangeland Reclamation, Stanford A. Young, Jason Vernon, Nancy Shaw
Basin Wildrye (Leymus Cinereus) Pooled Tetraploid Accessions For U.S. Intermountain West Rangeland Reclamation, Stanford A. Young, Jason Vernon, Nancy Shaw
IGC Proceedings (1977-2023)
Basin wildrye (Leymus cinereus [Scribn. & Merr.] Á. Löve) is an important perennial, hardy, long-lived, cool season C3 native grass of rangeland plant communities throughout much of western United States and Canada. All classes of livestock and wildlife, including large and small birds and mammals, utilise the grass year round for food and protection due to its 2-3 m tall, stiff stature which provides standing winter cover. Though occurring in precipitation areas of 150-500 mm and elevations of 600 to 3,000 m, it is usually found in deep, well-drained soils of high water holding capacity along drainage areas. Seedling …
Summer Dormancy Expression In The Australian Native Grass Elymus Scaber, Matthew Newell, Richard C. Hayes, Jim Virgona, Philip Larkin
Summer Dormancy Expression In The Australian Native Grass Elymus Scaber, Matthew Newell, Richard C. Hayes, Jim Virgona, Philip Larkin
IGC Proceedings (1977-2023)
Complete summer dormancy is associated with plant senescence in late spring-summer even though soil moisture is non-limiting. The trait is well understood in exotic temperate grasses for persistence in environments which experience frequent summer droughts (Annicchiarico et al. 2011). However, the trait appears to be uncommon in Australian native grasses (Culvenor 2009). The C3 native perennial grass, Elymus scaber, is broadly adapted across a wide range of climatic zones and soil types in south eastern Australia (Johnston et al. 2001) and has been described as displaying strong summer dormancy (Mitchell et al. 2001). However, the reports …
Challenges To Domesticating "Native" Forage Legumes, James P. Muir, José C. B. Dubeux Jr., Mércia V. F. Dos Santos, Inacio C. Maposse, William D. Pitman, Twain J. Butler
Challenges To Domesticating "Native" Forage Legumes, James P. Muir, José C. B. Dubeux Jr., Mércia V. F. Dos Santos, Inacio C. Maposse, William D. Pitman, Twain J. Butler
IGC Proceedings (1977-2023)
If ruminant production from cultivated and natural grasslands is to depend less on petroleum-based products, forage legumes must serve as protein sources. Commercially available legumes for warm-dry climate grasslands are, however, very limited and resources available for developing such legumes are inadequate. Indeterminate flowering and dehiscent seed pods combined with the need for specialized seed harvesting equipment are major impediments (Butler and Muir 2012). Warm climates often present environmental challenges such as poor rainfall distribution, extended dry seasons, temperature extremes and aggressive grass species (Muir et al. 2011). Erosion of indigenous knowledge and replacement with inappropriate land management approaches …
Row Spacing Effects On Biomass Components And Accumulated Energy In Elymus Sibiricus L., Jinping Liu, Minghong You
Row Spacing Effects On Biomass Components And Accumulated Energy In Elymus Sibiricus L., Jinping Liu, Minghong You
IGC Proceedings (1977-2023)
Elymus sibiricus L. is widely distributed in the eastern Tibetan Plateau of China. Current research on E. sibiricus mainly focuses on resource assessment, breeding, cultivation and dynamics of forage yield. Little is known about the effects of row spacing on the biomass components and accumulated energy of E. sibiricus. We conducted a study to determine the effects of row spacing on biomass components and accumulated energy in E. sibiricus. These data are important to optimize forage and seed production of E. sibiricus, and can assist in developing animal husbandry, structurally adjusting the agricultural industry and protecting the …
Seeding Rate And Row-Spacing Effects On Seed Yield And Yield Components Of Leymus Chinensis (Trin.) Tzvel., Yunhua Han, Xianguo Wang, Tianming Hu, Zhenlei Zhu, Zhengwei Wang, Ying Wang
Seeding Rate And Row-Spacing Effects On Seed Yield And Yield Components Of Leymus Chinensis (Trin.) Tzvel., Yunhua Han, Xianguo Wang, Tianming Hu, Zhenlei Zhu, Zhengwei Wang, Ying Wang
IGC Proceedings (1977-2023)
Chinese sheepgrass (Leymus chinensis (Trin.) Tzvel.) is widely distributed in the eastern portion of the Inner Mongolian Plateau and the Songnen Grassland of China. This grass is highly salt, cold and drought tolerant and has been the major source of forage for cows and other ruminants in China (Gao et al. 2012). Seed yield of this grass is very low under native conditions because of the low heading percentage and percentage of seed set (Wang et al. 2010). The Hexi Corridor, located in China’s northwestern Gansu Province, is the seed production center of China because of its …
Using Common Gardens And Aflp Analyses To Identify Metapopulations Of Indigenous Plant Materials For Rangeland Revegetation In Western Usa, Douglas A. Johnson, B. Shaun Bushman, Thomas A. Jones, Kishor Bhattarai
Using Common Gardens And Aflp Analyses To Identify Metapopulations Of Indigenous Plant Materials For Rangeland Revegetation In Western Usa, Douglas A. Johnson, B. Shaun Bushman, Thomas A. Jones, Kishor Bhattarai
IGC Proceedings (1977-2023)
Past mismanagement, overgrazing, invasive weedy species, wildfires, marginal crop production, mineral and energy extraction, recreation and global climate change are challenges currently facing rangelands (Pierson et al. 2011). These disturbances may lead to long-term reductions in biodiversity, altered nutrient and water cycling, diminished forage production for livestock and wildlife, increased wildfire frequency and increased soil erosion and stream sedimentation (Sheley et al. 2008). Rangeland revegetation with desirable plant materials may be required to improve degraded conditions, speed recovery, and prevent further erosion and degradation. There is a critical need for plant materials to restore and revegetate rangeland ecosystems. …
Seed Rain Of A Native Pasture Under A Range Of Grazing And Fertiliser Regimes, Zhongnan Nie, Reto Zollinger
Seed Rain Of A Native Pasture Under A Range Of Grazing And Fertiliser Regimes, Zhongnan Nie, Reto Zollinger
IGC Proceedings (1977-2023)
In recent years, deferred grazing (no defoliation of pastures for a period generally from spring to late summer or autumn) has been widely adopted to rejuvenate degraded native pastures in marginal land classes such as steep hill country in western Victoria, Australia. One of the important features of deferred grazing is the increase of seed production over summer and autumn, which could potentially lead to natural regeneration and improved groundcover by pasture plants (Nie et al. 1999). While increasing seed numbers in the soil seed bank following deferred grazing were reported (Nie and Mitchell 2006), there has been little …
Genetic Variation And Geographical Differentiation Of Elymus Nutans (Poaceae: Triticeae) From West China, Shiyong Chen, Xinquan Zhang, Xiao Ma, Jiamin Miao
Genetic Variation And Geographical Differentiation Of Elymus Nutans (Poaceae: Triticeae) From West China, Shiyong Chen, Xinquan Zhang, Xiao Ma, Jiamin Miao
IGC Proceedings (1977-2023)
Elymus nutans Griseb. is not only an important alpine forage grass, but also as a crucial gene pool for improving cereal crops. Understanding and maintaining the genetic diversity of the species are essential for both conservation strategy and breeding programs. However, little is known about its genetic and geographical differentiation patterns. E. nutans is a perennial, caespitose and allohexaploid (2n=6x=42) species that contains the St, H and Y genomes. It is native to temperate and tropical Asia, ranging from western and central Asia in the west to China and Mongolia in the east, from Russia in the north to India …
Seed Ecology Of Microlaena Stipoides In Grazing Systems Of South-Eastern Australia, Meredith L. Mitchell, James M. Virgona, Joe Jacobs, David R. Kemp
Seed Ecology Of Microlaena Stipoides In Grazing Systems Of South-Eastern Australia, Meredith L. Mitchell, James M. Virgona, Joe Jacobs, David R. Kemp
IGC Proceedings (1977-2023)
Microlaena stipoides var. stipoides (Labill.) R.Br. (Microlaena) is a tufted C3 native Australian perennial grass with a short rhizome that can form dense lawns. Microlaena has a wide geographic distribution throughout southern Australia, particularly in the temperate, high-rainfall tableland areas (> 550 mm AAR) of south-eastern and western Australia where is considered to be important for the grazing industries because of its extended growing season in higher rainfall areas, persistence over many years and persistence through drought. Although Microlaena has an important role in the stability of grazed native pastures, little is known about this grass in grazed communities. This …
Technical Challenges In Evaluating Southern China’S Forage Germplasm Resources, Changjun Bai, Guodao Liu, Yu Zhang, Daogeng Yu
Technical Challenges In Evaluating Southern China’S Forage Germplasm Resources, Changjun Bai, Guodao Liu, Yu Zhang, Daogeng Yu
IGC Proceedings (1977-2023)
The present status of the collection, conservation and utilisation of the pasture germplasm in tropical and subtropical zones in China is reviewed. The Tropical Pasture Research Centre (TPRC) of Chinese Academy of Tropical Agricultural Sciences (CATAS) has been engaged in this research since the 1940s. A low temperature gene bank, an in vitro plant library and a nursery station have been established. In total, 5890 indigenous fodder materials belonging to 478 species, 161 genera and 12 families have been surveyed and collected in South China; 1130 exotic materials belonging to 87 species, 42 genera of grasses and legumes have been …
World Interest In Diverse Native Plant Stands, Michael P. Schellenberg, Bili Biligetu, Eric G. Lamb, Jenalee M. Mischkolz
World Interest In Diverse Native Plant Stands, Michael P. Schellenberg, Bili Biligetu, Eric G. Lamb, Jenalee M. Mischkolz
IGC Proceedings (1977-2023)
The objective of this paper was to provide a brief overview of native plant use and development including examples of native plant research being conducted in Canada. There is increasing interest in native plants in various countries. Currently, native plants are used in reclamation, biomass biofuel production, forage seeding, habitat restoration, and water and soil conservation efforts. Many countries have active programs for native plant preservation and new germplasm development, but seed cost, seed quality, and ease of establishment are still challenges for large-scale use. Many improved native plant germplasms have been released in recent years. In some countries, legislation …
The Values Of Warm-Season Native Perennial Grasses Grown For Pasture Or Biofuel In The Southern Great Plains, Usa, James K. Rogers, Bryan Nichols, Jon T. Biermacher, Jagadeesh Mosali
The Values Of Warm-Season Native Perennial Grasses Grown For Pasture Or Biofuel In The Southern Great Plains, Usa, James K. Rogers, Bryan Nichols, Jon T. Biermacher, Jagadeesh Mosali
IGC Proceedings (1977-2023)
The Renewable Fuel Standard under the Energy Independence and Security Act of 2007 mandated the production of 136 billion liters of cellulosic biofuel by 2022. Switchgrass (Panicum virgatum) has been identified as a primary feedstock because it is a perennial, produces high yields and is adapted to a wide environmental range. Development of the cellulosic biofuel industry has been slow. A reason for this slow development is lack of available feedstock driven by lack of a developed market. Rather than considering switchgrass only as a dedicated biofuel feedstock, we examined its potential both for grazing and biofuel feedstock. …
Microscopic Fabric Characteristics Of Typical Red Soft Rock In Badong Formation Under Uniaxial Compression Test, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen
Microscopic Fabric Characteristics Of Typical Red Soft Rock In Badong Formation Under Uniaxial Compression Test, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen
Coal Geology & Exploration
Red silty mudstone and argillaceous siltstone are the representatives of special rock and soil in Badong Formation, are easy to disintegrate when encountering water. According to the uniaxial compression test of rock samples, a numerical model of medium and soft rock uniaxial compression test was established based on PFC2D program. With the characteristics of stress-strain curve, subsection quantitative parameter calibration method was used to calibrate the microscopic parameters of soft rock samples. The adjustment method and the ratio of tangential bond strength(σc/τc) control specimen under uniaxial compression failure mode. The uniaxial compression test of silty …
Analysis Of Suitable Development Technology Of Cbm(Gas) In Guizhou, Xu Xiaoqian, Meng Yingfang, Duan Zhengpeng, Li Guohong, Li Qingsong
Analysis Of Suitable Development Technology Of Cbm(Gas) In Guizhou, Xu Xiaoqian, Meng Yingfang, Duan Zhengpeng, Li Guohong, Li Qingsong
Coal Geology & Exploration
In recent years, technical bottlenecks have been encountered in the practice of CBM exploration and development in Guizhou Province, selecting suitable development technology is one of the key issues. Based on the background that CBM exists in thin coal seams and geological structures are complicated in Guizhou, combined with successful development and utilization of CBM, the CBM development and utilization technology suitable for complex geological conditions in Guizhou was put forward. Air drilling is recommended for drilling in Guizhou, according to different distance of thin seams, such as optical casing composite fracturing and salvageable bridge plug fracturing can be used. …
Key Technology Of Drilling In-Seam Directional Borehole Of 3 000 M In Underground Coal Mine, Shi Zhijun, Dong Shuning, Yang Junzhe, Xu Chao, Hao Shijun, Li Quanxin, Chen Dianfu, Yao Ke, Liu Jianlin, Tian Dongzhuang
Key Technology Of Drilling In-Seam Directional Borehole Of 3 000 M In Underground Coal Mine, Shi Zhijun, Dong Shuning, Yang Junzhe, Xu Chao, Hao Shijun, Li Quanxin, Chen Dianfu, Yao Ke, Liu Jianlin, Tian Dongzhuang
Coal Geology & Exploration
The pre-mining gas governance mode in Baode coal mine requires that long directional borehole of more than 3 000 m can be drilled along coal seam. In view of the existing technology and equipment, there are technical problems in the construction of ultra-long directional borehole, such as the difficulty of sliding drilling, the large hydraulic pressure consumption in inlet waterway, the limited transmission distance of wireline MWD signal, and incapability of flushing liquid recycle. The technology of friction reduction in sliding drilling based on the hydraulic thrust of DHM and the torsion penetration of the ultra-long drilling tool, the technology …
Extension Model Of Fracturing Cracks Of Translayer Horizontal Well In Roof Of Soft Coal Reservoir, Wang Zhirong, Hu Kai, Yang Jie, Chen Lingxia
Extension Model Of Fracturing Cracks Of Translayer Horizontal Well In Roof Of Soft Coal Reservoir, Wang Zhirong, Hu Kai, Yang Jie, Chen Lingxia
Coal Geology & Exploration
In order to study the propagation rules of hydraulic fracturing crack formed by a horizontal well in roof to coal seam, taking the Permian-Carboniferous coal field in North China as an example, through the classical theory of fracture mechanics, damage mechanics and fluid mechanics, combined with field actual data, the modeling and verification of the space-time evolution law of the crack propagation distance and fracturing time were carried out. Firstly, considering the additional stress of perforation, the characteristics of primary fracture and the permeability characteristics of rock formation, the calculation formula of cracking pressure of vertical hydraulic fracture caused by …
Technology Feasibility Of Gas Drainage With Comb-Shaped Long Borehole In Floor Instead Of Translayer Borehole, Li Hong, Liu Mingju, Hao Guangsheng, Deng Qigen, Dong Yanjun
Technology Feasibility Of Gas Drainage With Comb-Shaped Long Borehole In Floor Instead Of Translayer Borehole, Li Hong, Liu Mingju, Hao Guangsheng, Deng Qigen, Dong Yanjun
Coal Geology & Exploration
Drainage technology of translayer borehole in floor roadway and directional long hole are the most important gas control measures in high gas and outburst-prone mining face at present. The coal seam in Zhaozhuang mine has the characteristics of being soft and low gas permeability. It is difficult to drill and form holes in a coal seam. For gas control, the major method is to drill a translayer borehole to eliminate gas outburst, supplemented by in-seam gas drainage boreholes. However, there are shortcomings such as large engineering volume, long construction period and high cost of drilling in floor rock roadway. The …
An Improved Method For Characterizing Coal Metamorphism By Xrd, Wang Chao, Zhao Younan, Wang Zhenwei, Lu Zhaolin
An Improved Method For Characterizing Coal Metamorphism By Xrd, Wang Chao, Zhao Younan, Wang Zhenwei, Lu Zhaolin
Coal Geology & Exploration
At present, the X-ray measurement method of coal metamorphism has the problem that the γ band is not well divided, the δ peak information is not used, and the background of the bottom is unreasonable. The X-ray diffraction pattern of coal with different metamorphosed degrees is compared and studied. It is proposed to correct the metamorphic coefficient formula by using the information of the slope of the 002 peak, the extended half-height width and the δ peak without deducting the so-called background information. The calculation of the XRD patterns of coal samples with different degrees of metamorphism is verified. The …
Effect Of False Boundary Of Microscopic Image On Automatic Identification Of Maceral Group, Song Xiaozhong
Effect Of False Boundary Of Microscopic Image On Automatic Identification Of Maceral Group, Song Xiaozhong
Coal Geology & Exploration
In automatic detection of coal petrology by image analysis technology, it is found that the boundary of various components in the microscopic image of coal petrology demonstrates a "rim" of gray transition zone, and the pixel of this rim cannot reflect the true gray level of the components on both sides. In order to analyze its influence on the identification and detection of macerals, the characteristics and causes of the false boundary between various adjacent components were studied with analysis of microscopic images collected from a large number of coal samples in China. Generally, the false boundary is ring-shaped or …
Effects Of Iron-Nickel Ion Combination On Methane Produced By Lignite Fermentation, Xia Daping, Huang Song, Zhang Huaiwen
Effects Of Iron-Nickel Ion Combination On Methane Produced By Lignite Fermentation, Xia Daping, Huang Song, Zhang Huaiwen
Coal Geology & Exploration
In order to study the mechanism of the influence of exogenous optimal iron-nickel ions combination on the gas production process of fermentation, taking Daliuta lignite as an example, experiments were carried out with different contents of iron-nickel ions and the optimal concentration of single ions was elected. The optimal combination concentration of iron-nickel ions were determined by combined design of quadratic regression and common rotation. The fermentation broth of experiment group and blank group(not to added any ions), the coal sample of before and after experiment were analyzed by gas chromatography, X-ray diffraction, Fourier transform infrared spectroscopy, etc. The results …
Origin And Geochemical Characteristics Of Coalbed Methane In Abandoned Coal Mines, Panzhuang Block, Southern Qinshui Basin, Liu Chao, Feng Guorui, Zeng Fangui
Origin And Geochemical Characteristics Of Coalbed Methane In Abandoned Coal Mines, Panzhuang Block, Southern Qinshui Basin, Liu Chao, Feng Guorui, Zeng Fangui
Coal Geology & Exploration
In order to analyze the carbon and oxygen composition and origin of the coal seam gas(CSG) in abandoned mines, Panzhuang block, south of Qinshui basin, in this paper, the coalbed methane and produced water samples were collected. The results show that the CSG of abandoned mines is dominated by CH4, the average is 91.99%, with minor amounts of N2(6.73%) and CO2(1.26%). The δ13C values of CH4 range from -31.36‰ to -33.53‰, with an average of -32.25‰, the hydrogen isotope(δD) value is between -182.76‰ and -193.20‰, and the average value …
Mine Water Inrush Rescue Model Based On Optimized Spfa Algorithm, Cai Mingjie, Zhu Xi’An, Liu Demin, Wang Zhangang
Mine Water Inrush Rescue Model Based On Optimized Spfa Algorithm, Cai Mingjie, Zhu Xi’An, Liu Demin, Wang Zhangang
Coal Geology & Exploration
Due to the occurrence of coal mine water inrush accidents, it is easy to cause major personnel and property losses. In order to improve the emergency rescue capability of mine water inrush disasters and reduce the water inrush hazard, a mine water inrush rescue route model was proposed. The undirected map and the adjacency list were used to describe and store the mine roadway network. According to the calculation ratio of the height of the water level and the height of underground personnel in roadway, the safety coefficient of the roadway was calculated, and then the equivalent length of the …
Optimization Study On Correlation Method Of Multiple Coal Seams, Shu Jiansheng, Ma Liang, Jia Lilong
Optimization Study On Correlation Method Of Multiple Coal Seams, Shu Jiansheng, Ma Liang, Jia Lilong
Coal Geology & Exploration
At present, the development trend of coal mining in China is transferring from the east to the western regions. The Yan'an Formation coal bearing measures middle Jurassic is the most widely distributed in the west, it is of the continental sedimentary environment, which has the characteristics of big change of lithofacies, multiple coal seams, unstable coal seams and less marker, there are difficulties in coal seam correlation, such as lack of basis and multi-solution phenomenon. Based on the wide application of high precision seismic exploration and digital logging technology, the fine correlation of terrestrial multi-coal seams was carried out by …