Aiming to address the following major engineering issues faced by the Pingdingshan No. 12 mine:(1) difficulty in implementing auxiliary lifting because of its depth(i.e., beyond 1000 m);(2) highly gassy main coal seam...Aiming to address the following major engineering issues faced by the Pingdingshan No. 12 mine:(1) difficulty in implementing auxiliary lifting because of its depth(i.e., beyond 1000 m);(2) highly gassy main coal seam with low permeability;(3) unstable overlying coal seam without suitable conditions for implementing conventional mining techniques for protective coal seam; and(4) predominant reliance on ‘‘under three" coal resources to ensure production output. This study proposes an integrated, closed-cycle mining-dressing-gas draining-backfilling-mining(MDGBM) technique. The proposed approach involves the mining of protective coal seam, underground dressing of coal and gangue(UDCG), pressure relief and gas drainage before extraction, and backfilling and mining of the protected coal seam. A system for draining gas and mining the protective seam in the rock stratum is designed and implemented based on the geological conditions. This system helps in realizing pressure relief and gas drainage from the protective seam before extraction. Accordingly, another system, which is connected to the existing production system, is established for the UDCG based on the dense medium-shallow trough process. The mixed mining workface is designed to accommodate both solid backfill and conventional fully mechanized coal mining, thereby facilitating coal mining, USCG, and backfilling. The results show that: The mixed mining workface length for the Ji15-31010 protected seam was 220 m with coal production capacity 1.2 million tons per year, while the backfill capacity of gangue was 0.5 million tons per year. The gas pressure decreased from 1.78 to 0.35 MPa, and the total amount of safely mined coal was 1.34 million tons. The process of simultaneously exploiting coal and draining gas was found to be safe, efficient, and green.This process also yielded significant economic benefits.展开更多
Fenneropenaeus penicillatus （redtail shrimp） is an important marine commercial animal in China. Recently, its resources have been depleted rapidly as a result of, for example, over-exploitation and environmental deg...Fenneropenaeus penicillatus （redtail shrimp） is an important marine commercial animal in China. Recently, its resources have been depleted rapidly as a result of, for example, over-exploitation and environmental degradation of spawning grounds. Therefore, we analyzed the genetic diversity and differentiation of nine wild populations of F. penicillatus of China （Ningde, Lianjiang, Putian, Xiamen, Quanzhou, Zhangpu, Dongshan, Nanao, and Shenzhen populations） by amplified fragment .!ength polymorphism （AFLP） technology, to provide genetic information necessary for resource protection, rejuvenation, artificial breeding, and sustainable use of the resource. Eight AFLP primer pairs were used for amplification, and 508 bands were detected among the populations. The results show that the percentage of polymorphic loci （P） ranged from 41.34% to 63.58%; the Nei＇s gene diversity （H） of the populations was 0.119 4-0.230 5; and Shannon＇s Information Index （/） was 0.184 1-0.342 5. These genetic data indicate that the genetic diversity of F. penicillatus was high. The genetic differentiation coefficient （GsT=0.216 2） and gene flow （Nm=1.812 4） show that there was a high level of genetic differentiation and a moderate level of gene flow among populations. More studies on the genetic differentiation mechanism of F. peniillatus along the south-eastem coast of China need to be conducted to find more effective scientific protection strategies for the conservation ofF. penicillatus genetic resources.展开更多
The encapsulation in a nutritive matrix is an effective technique which allows the conservation of vitro-derived explants and protects their viability. The encapsulated propagules are generated by submerging explants ...The encapsulation in a nutritive matrix is an effective technique which allows the conservation of vitro-derived explants and protects their viability. The encapsulated propagules are generated by submerging explants in a natural polysaccharide solution of sodium alginate and calcium chloride allowing to obtain uniform capsules. In this work, we present preliminary results of a study on the effect of an encapsulation protocol on any local fruit varieties, conserved in a Regional in vitro germplasm bank.展开更多
To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lympho...To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lymphocyte culture technique was carried out in 28 Tho-Tho cattle and culture was harvested for good metaphase spread. Good metaphase spreads were selected for analysis, such as relative length, centromeric index and arm ratio. Centromeric banding （C-banding） and reverse banding （R-banding） methods were done for detail and better understanding of the chromosome morphology. The chromosome number in Tho-Tho cattle was observed to be 2n = 60 in all complete metaphase. The mean relative length of the autosomal chromosomes varied from 5.48% ：~ 0.107% to 1.79% ＋ 0.105% in male and 5.31% ：E 0.148% to 1.86% ＋ 0.055% in female, respectively. The chromosome banding showed C-positive dark band heterochromatin in all the acrocentric autosome. However, in sex chromosome, the Y-chromosome showed negative C-band and also the X-chromosome did not show any stain at the centromeric region. The numbers of R-band pattern were observed to be 490 and 499 band in male and female, respectively. One of the X-chromosome showed light banding pattern, confirming the inactivation during the embryonic development in female. The fundamental chromosome number and banding pattern of Tho-Tho cattle did not vary from the other breed of the Bos indicus. However, it is necessary to start a cytogenetic screening of the Tho-Tho cattle and expand upon more number to be kept at different villages of Nagaland in order to identify animals with chromosomal abnormalities, so that it can be excluded from future breeding strategies for conservation of Tho-Tho genetic resource.展开更多
基金supported by the Qing Lan Project Foundation of Jiangsu Province in 2014,Foundation for Distinguished professor of Jiangsu Province in 2015,Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.51421003)Project funded by China Postdoctoral Science Foundation(2016M601915)National Key Basic Research Program of China(No.2013CB227905)
文摘Aiming to address the following major engineering issues faced by the Pingdingshan No. 12 mine:(1) difficulty in implementing auxiliary lifting because of its depth(i.e., beyond 1000 m);(2) highly gassy main coal seam with low permeability;(3) unstable overlying coal seam without suitable conditions for implementing conventional mining techniques for protective coal seam; and(4) predominant reliance on ‘‘under three" coal resources to ensure production output. This study proposes an integrated, closed-cycle mining-dressing-gas draining-backfilling-mining(MDGBM) technique. The proposed approach involves the mining of protective coal seam, underground dressing of coal and gangue(UDCG), pressure relief and gas drainage before extraction, and backfilling and mining of the protected coal seam. A system for draining gas and mining the protective seam in the rock stratum is designed and implemented based on the geological conditions. This system helps in realizing pressure relief and gas drainage from the protective seam before extraction. Accordingly, another system, which is connected to the existing production system, is established for the UDCG based on the dense medium-shallow trough process. The mixed mining workface is designed to accommodate both solid backfill and conventional fully mechanized coal mining, thereby facilitating coal mining, USCG, and backfilling. The results show that: The mixed mining workface length for the Ji15-31010 protected seam was 220 m with coal production capacity 1.2 million tons per year, while the backfill capacity of gangue was 0.5 million tons per year. The gas pressure decreased from 1.78 to 0.35 MPa, and the total amount of safely mined coal was 1.34 million tons. The process of simultaneously exploiting coal and draining gas was found to be safe, efficient, and green.This process also yielded significant economic benefits.
基金Supported by the Natural Science Foundation of Fujian Province (No.2010J01213)the Special Program for Fujian Provincial Universities (No.JK2010034)+1 种基金the Program for New Century Excellent Talents in Fujian Province Universitythe Foundation for Innovative Research Team of Jimei University, China (No. 2010A004)
文摘Fenneropenaeus penicillatus （redtail shrimp） is an important marine commercial animal in China. Recently, its resources have been depleted rapidly as a result of, for example, over-exploitation and environmental degradation of spawning grounds. Therefore, we analyzed the genetic diversity and differentiation of nine wild populations of F. penicillatus of China （Ningde, Lianjiang, Putian, Xiamen, Quanzhou, Zhangpu, Dongshan, Nanao, and Shenzhen populations） by amplified fragment .!ength polymorphism （AFLP） technology, to provide genetic information necessary for resource protection, rejuvenation, artificial breeding, and sustainable use of the resource. Eight AFLP primer pairs were used for amplification, and 508 bands were detected among the populations. The results show that the percentage of polymorphic loci （P） ranged from 41.34% to 63.58%; the Nei＇s gene diversity （H） of the populations was 0.119 4-0.230 5; and Shannon＇s Information Index （/） was 0.184 1-0.342 5. These genetic data indicate that the genetic diversity of F. penicillatus was high. The genetic differentiation coefficient （GsT=0.216 2） and gene flow （Nm=1.812 4） show that there was a high level of genetic differentiation and a moderate level of gene flow among populations. More studies on the genetic differentiation mechanism of F. peniillatus along the south-eastem coast of China need to be conducted to find more effective scientific protection strategies for the conservation ofF. penicillatus genetic resources.
文摘The encapsulation in a nutritive matrix is an effective technique which allows the conservation of vitro-derived explants and protects their viability. The encapsulated propagules are generated by submerging explants in a natural polysaccharide solution of sodium alginate and calcium chloride allowing to obtain uniform capsules. In this work, we present preliminary results of a study on the effect of an encapsulation protocol on any local fruit varieties, conserved in a Regional in vitro germplasm bank.
文摘To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lymphocyte culture technique was carried out in 28 Tho-Tho cattle and culture was harvested for good metaphase spread. Good metaphase spreads were selected for analysis, such as relative length, centromeric index and arm ratio. Centromeric banding （C-banding） and reverse banding （R-banding） methods were done for detail and better understanding of the chromosome morphology. The chromosome number in Tho-Tho cattle was observed to be 2n = 60 in all complete metaphase. The mean relative length of the autosomal chromosomes varied from 5.48% ：~ 0.107% to 1.79% ＋ 0.105% in male and 5.31% ：E 0.148% to 1.86% ＋ 0.055% in female, respectively. The chromosome banding showed C-positive dark band heterochromatin in all the acrocentric autosome. However, in sex chromosome, the Y-chromosome showed negative C-band and also the X-chromosome did not show any stain at the centromeric region. The numbers of R-band pattern were observed to be 490 and 499 band in male and female, respectively. One of the X-chromosome showed light banding pattern, confirming the inactivation during the embryonic development in female. The fundamental chromosome number and banding pattern of Tho-Tho cattle did not vary from the other breed of the Bos indicus. However, it is necessary to start a cytogenetic screening of the Tho-Tho cattle and expand upon more number to be kept at different villages of Nagaland in order to identify animals with chromosomal abnormalities, so that it can be excluded from future breeding strategies for conservation of Tho-Tho genetic resource.
