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Analysis of genetic diversity and population structure of Chinese yak breeds (Bos grunniens) using microsatellite markers 被引量:8
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作者 guixiang zhang Weisheng Chen +5 位作者 Ming Xue Zhigang Wang Hong Chang Xu Han Xinjun Liao Donglei Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第4期233-238,共6页
Nine Chinese yak breeds (Maiwa, Tianzhu White, Qinghai Plateau, Sibu, Zhongdian, Pali, Tibetan High Mountain, Jiulong, and Xinjiang) and Gayal were analyzed by means of 16 microsatellite markers to determine the lev... Nine Chinese yak breeds (Maiwa, Tianzhu White, Qinghai Plateau, Sibu, Zhongdian, Pali, Tibetan High Mountain, Jiulong, and Xinjiang) and Gayal were analyzed by means of 16 microsatellite markers to determine the level of genetic variation within populations, genetic relationship between populations, and population structure for each breed. A total of 206 microsatellite alleles were observed. Mean F-statistics (0.056) for 9 yak breeds indicated that 94.4% of the genetic variation was observed within yak breeds and 5.6% of the genetic variation existed amongst breeds. The Neighbor-Joining phylogenetic tree was constructed based on Nei's standard genetic distances and two clusters were obtained. The Gayal separated from the yaks far away and formed one cluster and 9 yak breeds were grouped together. The analysis of population structure for 9 yak breeds and the Gayal showed that they resulted in four clusters; one cluster includes yaks from Tibet Autonomous Region and Qinghai Province, one cluster combines Zhongdian, Maiwa, and Tianzhu White, and Jiulong and Xinjiang come into the third cluster. Pali was mainly in the first cluster (90%), Jiulong was mainly in the second cluster (87.1%), Zhongdian was primarily in the third cluster (83%), and the other yak breeds were distributed in two to three clusters. The Gayal was positively left in the fourth cluster (99.3%). 展开更多
关键词 Chinese yak breeds MICROSATELLITE genetic diversity population structure
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Evaluation and welfare effect of coordinated ecological development of the Beijing-Tianjin-Hebei region
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作者 Linlin Zhao guixiang zhang 《Chinese Journal of Population,Resources and Environment》 2021年第3期283-290,共8页
Regional coordinated ecological development is a new form of regional coordinated development that aims to construct an ecological civilization in the“new normal”period.The coordinated ecological development of the ... Regional coordinated ecological development is a new form of regional coordinated development that aims to construct an ecological civilization in the“new normal”period.The coordinated ecological development of the Beijing-Tianjin-Hebei(BTH)region is especially significant because this region is leading the overall coordinated development and reform in China.Based on complex system theory,synergetics,and the ecological civilization and green development ideas of the“new normal”period,we constructed a regional ecological synergy measurement model that scientifically evaluates the dynamic evolution of the BTH ecological synergy level from 2006 to 2018.Using an econometric model,we also analyzed the welfare effect and the regional heterogeneity of ecological synergy in regional development.First,it was found that in general,the degree of ecological synergy in BTH increased yearly up to 2018 with a strong development trend.The speed of ecological synergy in the Tianjin-Hebei and Beijing-Hebei subsystems was accelerating during that period,but the development potential of the ecological synergy in Beijing-Tianjin was insufficient and slow-growing.Second,whereas Beijing had entered the stage of moderate coordinated ecological development,Tianjin and Hebei remained in the low level of coordinated development;moreover,the coordinated development was unstable.The uneven development of the internal subsystems in BTH restricted the development of the cooperative effect and the overall development of the region.Third,improving the degree of ecological synergy significantly benefited the social and economic welfare in BTH.Finally,the welfare effect of the degree of ecological synergy showed a significant regional heterogeneity,being significantly higher in Tianjin and Hebei than in Beijing.This result indicates that improving the ecological synergy can narrow the development gaps between Tianjin,Hebei,and Beijing.To further improve the level of regional ecological synergy,we should innovate the coordinated model of regional development,implement the collaborative ecological development model,generate new growth drivers for the green development of BTH based on a reasonable division of labor,difference positioning,and active integration,create a soft environment for an innovation ecosystem that promotes regional ecological synergy,and build a regional innovation ecosystem led by Beijing and Xiongan.Next,we should establish a balanced regional-interest mechanism with ecological environmental protection that supports regional green and high-quality development. 展开更多
关键词 Coordinated ecological development Ecological synergy Welfare effect Regional heterogeneity
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Green and large-scale production of ammonia:Laser-driven pyrolysis of nitrogen-enriched biomass 被引量:1
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作者 Yue Li Tong Wu +7 位作者 Yujie Wang Jiawei Li Wanqiang Yu guixiang zhang Bin Chang Lili Zhao Hong Liu Weijia Zhou 《SusMat》 2023年第4期533-542,共10页
As a vital chemical,ammonia(NH3)plays an irreplaceable role in many fields such as chemical synthesis and energy storage.Green renewable biomass can be converted into biofuels,but its nitrogen resources are underused ... As a vital chemical,ammonia(NH3)plays an irreplaceable role in many fields such as chemical synthesis and energy storage.Green renewable biomass can be converted into biofuels,but its nitrogen resources are underused throughout.Laser-driven pyrolysis is envisaged to debuts as a bridge to connect them to realize the direct conversion from nitrogen-rich biomass into ammonia.The pulsed laser-induced local-transient thermal effect recognized the biological nitrogen resources conversion,such as cheap and plentiful yeasts,to small gaseous molecules and achieved spectacular ammonia production rate up to 260.4 mg/h,an order of magnitude higher performance than thermochemical ammonia synthesis.Simultaneously,the tiny hot point generated by a low-energy laser(20W)guarantees the whole ammonia synthesis reaction systemis in amild environment of low temperature and normal pressure.Additionally,the remaining solid residue after laser-driven pyrolysis also can be further exploited as a highly active catalyst for electrocatalytic nitrate reduction reaction(NIRR). 展开更多
关键词 ammonia synthesis laser pyrolysis local temperature field nitrogen-enriched biomass wastes recycling
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Sorption of tetracycline to sediments and soils:assessing the roles of pH,the presence of cadmium and properties of sediments and soils 被引量:5
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作者 guixiang zhang Xitao LIU +2 位作者 Ke SUN Ye ZHAO Chunye LIN 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2010年第4期421-429,共9页
Batch sorption experiments were conducted to evaluate the sorption behavior of tetracycline(TC,H_(3)L)on sediments and soils in the presence and absence of cadmium(Cd),as affected by pH and properties of sediments and... Batch sorption experiments were conducted to evaluate the sorption behavior of tetracycline(TC,H_(3)L)on sediments and soils in the presence and absence of cadmium(Cd),as affected by pH and properties of sediments and soils.The results indicated stronger nonlinearity and higher capacity of TC sorption on sediments than on soils.Sorption of TC also strongly depended on environmental factors and sediment/soil properties.Lower pH facilitated TC sorption through a cation exchange mechanism,which also took place at pH values above 5.5,where TC existed as a zwitterion(H_(2)L^(0))or anions(HL^(-)and L^(2-)).When pH was above 7,however,ligand-promoted dissolution of TC might occur due to TC weakening the Al-O bond of aluminum oxide and the Fe-O bond of iron oxide.Natural organic matter(NOM)plays a more important role in TC sorption than cation exchange capacity(CEC)and clay contents.The presence of Cd(II)increased TC sorption on both sediments and soils,which resulted from the decrease of equilibrium solution pH caused by Cd^(2+)exchange with H^(+)ions of sediment/soil surfaces.The increase of TC sorption was also related to the formation of TC-Cd complexes,where Cd^(2+)acted as a bridge between the sediment/soil and TC. 展开更多
关键词 SORPTION tetracycline(TC) PH cadmium(Cd) antibiotic
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Detection of small ship targets from an optical remote sensing image 被引量:1
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作者 Mingzhu SONG Hongsong QU +1 位作者 guixiang zhang Guang JIN 《Frontiers of Optoelectronics》 EI CSCD 2018年第3期275-284,共10页
Detection of small ships from an optical remote sensing image plays an essential role in military and civilian fields. However, it becomes more difficult if noise dominates. To solve this issue, a method based on a lo... Detection of small ships from an optical remote sensing image plays an essential role in military and civilian fields. However, it becomes more difficult if noise dominates. To solve this issue, a method based on a low-level vision model is proposed in this paper. A global channel, high-frequency channel, and low-frequency channel are introduced before applying discrete wavelet transform, and the improved extended contrast sensitivity function is constructed by self-adaptive center-surround contrast energy and a proposed function. The saliency image is achieved by the three-channel process after inverse discrete wavelet transform, whose coefficients are weighted by the improved extended contrast sensitivity function. Experimental results show that the proposed method outperforms all competing methods with higher precision, higher recall, and higher F-score, which are 100.00%, 90.59%, and 97.96%, respectively. Furthermore, our method is robust against noise and has great potential for providing more accurate target detection in engineering applications. 展开更多
关键词 small target SALIENCY contrast sensitivity
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