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Assessing the conservation impact of Chinese indigenous chicken populations between ex-situ and in-situ using genome-wide SNPs
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作者 Wenting Li Chaoqun Gao +7 位作者 Zhao Cai Sensen Yan Yanru Lei Mengya Wei Guirong Sun Yadong Tian Kejun Wang Xiangtao Kang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期975-987,共13页
Conservation programs require rigorous evaluation to ensure the preservation of genetic diversity and viability of conservation populations. In this study, we conducted a comparative analysis of two indigenous Chinese... Conservation programs require rigorous evaluation to ensure the preservation of genetic diversity and viability of conservation populations. In this study, we conducted a comparative analysis of two indigenous Chinese chicken breeds, Gushi and Xichuan black-bone, using whole-genome SNPs to understand their genetic diversity, track changes over time and population structure. The breeds were divided into five conservation populations(GS1, 2010, ex-situ;GS2, 2019, ex-situ;GS3, 2019, in-situ;XB1, 2010, in-situ;and XB2, 2019, in-situ) based on conservation methods and generations. The genetic diversity indices of three conservation populations of Gushi chicken showed consistent trends, with the GS3 population under in-situ strategy having the highest diversity and GS2 under ex-situ strategy having the lowest. The degree of inbreeding of GS2 was higher than that of GS1 and GS3. Conserved populations of Xichuan black-bone chicken showed no obvious changes in genetic diversity between XB1 and XB2. In terms of population structure, the GS3 population were stratified relative to GS1 and GS2. According to the conservation priority, GS3 had the highest contribution to the total gene and allelic diversity in GS breed, whereas the contribution of XB1 and XB2 were similar. We also observed that the genetic diversity of GS2 was lower than GS3, which were from the same generation but under different conservation programs(in-situ and ex-situ). While XB1 and XB2 had similar levels of genetic diversity. Overall, our findings suggested that the conservation programs performed in ex-situ could slow down the occurrence of inbreeding events, but could not entirely prevent the loss of genetic diversity when the conserved population size was small, while in-situ conservation populations with large population size could maintain a relative high level of genetic diversity. 展开更多
关键词 genome-wide SNPs CONSERVATION genetic diversity ex-situ IN-SITU
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CdTe/Si复合衬底Ex-situ退火研究 被引量:8
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作者 刘铭 周立庆 +3 位作者 巩锋 常米 王经纬 王丛 《激光与红外》 CAS CSCD 北大核心 2012年第8期917-920,共4页
复合衬底CdTe/ZnTe/Si的晶体质量是导致随后外延的HgCdTe外延膜高位错密度的主要原因之一,因此如何提高复合衬底CdTe/Si晶体质量是确保硅基碲镉汞走上工程化的关键所在。降低复合衬底CdTe/Si位错密度方法一般有:生长超晶格缓冲层、衬底... 复合衬底CdTe/ZnTe/Si的晶体质量是导致随后外延的HgCdTe外延膜高位错密度的主要原因之一,因此如何提高复合衬底CdTe/Si晶体质量是确保硅基碲镉汞走上工程化的关键所在。降低复合衬底CdTe/Si位错密度方法一般有:生长超晶格缓冲层、衬底偏向、In-situ退火和Ex-situ退火等,本文主要研究Ex-situ退火对复合衬底CdTe/Si晶体质量的影响。研究表明复合衬底经过Ex-situ退火后位错密度最好值达4.2×105cm-2,双晶半峰宽最好值达60arcsec。 展开更多
关键词 CdTe/Si MBE 晶体质量 ex-situ退火
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Bamboo resources,utilization and ex-situ conservation in Xishuangbanna,South-eastern China 被引量:1
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作者 杨清 段柱标 +3 位作者 王正良 何开红 孙启祥 彭镇华 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期79-83,共5页
This paper describes the geographical distribution, utilization, cultural value and ex-situ conservation of bamboo resources in Xishuangbanna, Yunan Province, China. Sixty species of bamboo in 19 genera are recorded i... This paper describes the geographical distribution, utilization, cultural value and ex-situ conservation of bamboo resources in Xishuangbanna, Yunan Province, China. Sixty species of bamboo in 19 genera are recorded in Xishuangbanna. The area of natural bamboo forest is 14319 ha, accounting for 5.92% of whole area of Xishuangbanna. The abundant resource of bamboo plays an important role in the economics and culture of national minorities in Xishuangbanna. Xishuangbanna Tropic Botanic Garden, Chinese Academy of Sciences (CAS), started to introduce bamboo species in 1961 and established the ex-situ conservation reserve (8 ha) of bamboo in 1981. Up to now, 211 species in 27 genera collected from tropic and sub-tropic of China and South-east Asia have been planted in the bamboo reserve, of which 11 species have bloomed and seeded, and their seeds were cultivated in Xishuangbanna Tropical Botanic Gardens, CAS, China. 展开更多
关键词 XISHUANGBANNA bamboo resources UTILIZATION ex-situ conservation
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A plant nutrition strategy for ex-situ conservation based on "Ecological Similarity"
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作者 万开元 陈防 +2 位作者 陶勇 陈树森 张过师 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期329-334,共6页
This paper reviewed a large scale conservation work of rare and endangered plants currently conducted in main botanical gardens in China, and the existed, predictable and neglected problems on plant growth and reprodu... This paper reviewed a large scale conservation work of rare and endangered plants currently conducted in main botanical gardens in China, and the existed, predictable and neglected problems on plant growth and reproduction in ex-situ conservation process. Considered the status quo in plant ex conservation, a nutritional strategy on the plant conservation was proposed based on 'Ecological Similarity'. Its main idea was that the ex-situ conservation plants coming from natural ecosystem were compulsively allocated in the agro-ecosystems and would return to natural ecosystem ultimately. Therefore, research on plant nutrition of the ex-situ conservation plants should neither just pursue yield and quality as that in agro-ecosystems nor merely stay on intrinsic natures without human intervening. We should give attentions to both of their attributes as in natural ecosystems and in agro-ecosystems, i.e., taking full advantage of plant nutritional measures as in agro-ecosystems to solve actual survival problems of the ex-conservation plants, and ensuring the final goal of returning to nature and playing its ecological role. 展开更多
关键词 ex-situ conservation ecological similarity plant nutrition conservation strategy
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Ex-situ liver surgery without veno-venous bypass 被引量:8
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作者 Ke-Ming Zhang Xiong-Wei Hu +6 位作者 Jia-Hong Dong Zhi-Xian Hong Zhao-Hai Wang Gao-Hua Li Rui-Zhao Qi Wei-Dong Duan Shao-Geng Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第48期7290-7295,共6页
AIM:To evaluate the results of hepatic resection with ex-situ hypothermic perfusion and without veno-venous bypass.METHODS:In 3 patients with liver tumor,the degree of the inferior vena cava and/or main hepatic vein i... AIM:To evaluate the results of hepatic resection with ex-situ hypothermic perfusion and without veno-venous bypass.METHODS:In 3 patients with liver tumor,the degree of the inferior vena cava and/or main hepatic vein involvement was verified when the liver was dissociated in the operation.It was impossible to resect the tumors by the routine hepatectomy,so the patients underwent ex-situ liver surgery,vein cava replacement and hepatic autotransplantation without veno-venous bypass.All surgical procedures were carried out or supervised by a senior surgeon.A retrospective analysis was performed for the prospectively collected data from patients with liver tumor undergoing ex-situ liver surgery,vein cava replacement and hepatic autotransplantation without veno-venous bypass.We also compared our data with the 9 cases of Pichlmayr's group.RESULTS:Three patients with liver tumor were analysed.The first case was a 60-year-old female with a huge haemangioma located in S1,S4,S5,S6,S7 and S8 of liver;the second was a 64-year-old man with cholangiocarcinoma in S1,S2,S3 and S4 and the third one was a 55-year-old man with a huge cholangiocarcinoma in S1,S5,S7 and S8.The operation time for the three patients were 6.6,6.4 and 7.3 h,respectively.The anhepatic phases were 3.8,2.8 and 4.0 h.The volume of blood loss during operation were 1200,3100,2000 mL in the three patients,respectively.The survival periods without recurrence were 22 and 17 mo in the first two cases.As for the third case complicated with postoperative hepatic vein outflow obstruction,emergency hepatic vein outflow extending operation and assistant living donor liver transplantation were performed the next day,and finally died of liver and renal failure on the third day.Operation time(6.7 ± 0.47 h vs 13.7 ± 2.6 h) and anhepatic phase(3.5 ± 0.64 h vs 5.7 ± 1.7 h) were compared between Pichlmayr's group and our series(P = 0.78).CONCLUSION:Ex-situ liver resection and liver autotransplantation has shown a potential for treatment of complicated hepatic neoplasms that are unresectable by traditional procedures. 展开更多
关键词 Liver autotransplantation ex-situ resection Total vascular exclusion Liver tumor
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Implementing an innovated liver ex-situ machine perfusion technology:The 2018 Joint International Congress of ILTS,ELITA and LICAGE 被引量:2
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作者 Jun-Jun Jia Jian-Hui Li +2 位作者 Hai-Yang Xie Lin Zhoua Shu-Sen Zheng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第4期283-285,共3页
The 2018 Joint International Congress of ILTS,ELITA and LICAGE were held in Lisbon,Portugal on May 23–26,2018.The exciting and innovative program brought together 1144 experts in liver transplantation(LT)such as surg... The 2018 Joint International Congress of ILTS,ELITA and LICAGE were held in Lisbon,Portugal on May 23–26,2018.The exciting and innovative program brought together 1144 experts in liver transplantation(LT)such as surgeons,physicians or basic scientists from 61 countries.The presentations included 110 invited speakers,181 oral presentations,and 545 posters.This editorial highlights some of the most innovative and impactful presentations in 展开更多
关键词 NMP WIT DCD Implementing an innovated liver ex-situ machine perfusion technology:The 2018 Joint International Congress of ILTS ELITA and LICAGE
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Toughening of BMI Based Graphite Laminates by Ex-situ Concept
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作者 CHENG Qun-feng XU Ya-hong YI Xiao-su 《材料工程》 EI CAS CSCD 北大核心 2006年第5期41-45,共5页
High-performance bismaleimdes (BMI) matrix composites reinforced by graphite fibers were prepared and toughened with a thermoplastic component (PAEK) by using the Ex-situ concept. Experimental matrix was designed for ... High-performance bismaleimdes (BMI) matrix composites reinforced by graphite fibers were prepared and toughened with a thermoplastic component (PAEK) by using the Ex-situ concept. Experimental matrix was designed for overall toughening of the base resin, periodically interleaving thermoplastic films into each plies (Ex-situ concept) and for varying the film compositions. The highest impact damage resistance characterized by compression after impact (CAI) was obtained for the laminates toughened on the Ex-situ concept, especially, when two-component cast films of a special ration of PAEK/BMI 60∶40 were interleaved though the thermoplastic concentration for the overall toughening, interleaving the pure thermoplastic films and the two-component films was comparable. There were two peaks found in the DSC trace of the laminates toughened implying a phase separation process occurred. The glass transition temperature of the laminates toughened was slightly reduced due to the low-temperature PAEK. Morphological study revealed a typical granular structure just in the interplay region as a result of spinodal decomposition and coarsening process. This was in agreement of the result of DSC investigation. 展开更多
关键词 bismaleimdes compression after impact ex-situ concept
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Ex-situ Conservation of the some Medicinal Plants of Georgia
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作者 Tsira Mikatadze-Pantsulaia Tolkha Shetekauri Mariam Kikvidze 《Journal of Life Sciences》 2019年第1期5-11,共7页
The present work concerns with ex-situ Conservation issues study of the three economical species Cyclamen vernum Sweet is a synonym of Cyclamen coum subsp.caucasicum(K.Koch)O.Schwarz(Primulaceae)Helleborus caucasicus ... The present work concerns with ex-situ Conservation issues study of the three economical species Cyclamen vernum Sweet is a synonym of Cyclamen coum subsp.caucasicum(K.Koch)O.Schwarz(Primulaceae)Helleborus caucasicus A.Braun(Ranuculaceae)and Paeonia caucasica Schipcz)Schipcz.Is synonym of Paeonia dauricasubsp.Coriifolia(Rupr.)D.Y.Hong distribution in Georgia.These species are under strong anthropogenic stress,Its populations are collected in nature as a decorative and traditional medicinal properties.It is of urgent necessity to take conservation measures for these species through both ex-situ and in-situ protection methods.For this purpose it is of critical importance to collect data on the distribution of the above species and vitality and fertility of their populations.Processes of seed production and seed multiplication have been studied.The ex-situ base of the seed and live collection bank was created.The work is done in Great Britain within the framework of the“Millennium”Seed Bank Partnership of Kew Botanical Garden.The seeds are placed in the National Seed Bank,duplicates together with Herbarium sample are sent in the millennium seed bank.The live collection obtained from seeds is placed on the collection plot of Plant Conservation Department of the National Botanical Garden of Georgia. 展开更多
关键词 ex-situ CONSERVATION MEDICINAL PLANTS SEED BANK life COLLECTION
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Study on T700/Cyanate/PS/Epoxy Composites with ex-situ Toughening Technique
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作者 郑亚萍 WANG Hao +3 位作者 ZHANG Jiaoxia XU Yahong DAI Feng WANG Jihui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期674-678,共5页
Composites were prepared with polysulfone through ex-situ toughening technique. The dynamic parameters of cyanate/epoxy resin were studied by differential scanning calorimetric(DSC) analysis and dynamic mechanical a... Composites were prepared with polysulfone through ex-situ toughening technique. The dynamic parameters of cyanate/epoxy resin were studied by differential scanning calorimetric(DSC) analysis and dynamic mechanical analysis(DMA). Microstructual toughening mechanism was studied through scanning electron microscopy(SEM). The particle microstructure in interlaminar region of composites toughened through ex-situ toughening technique revealed that a reaction induced phase decomposition and phase inversion happened in the interlaminar region. The thermosetting particles were surrounded by the PS phase, which could signifi cantly improve the delamination resistance of composites. The compression after impact(CAI) can be signifi cantly improved from 180 MPa to 260 MPa by using ex-situ toughening while the mechanical properties are not affected. 展开更多
关键词 composites ex-situ toughening technique phase inversion microstructure
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Ex-Situ Cultivation of Medicinal Plant Species in High Altitudes at Swat,Pakistan
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作者 Hassan Sher David Melick Zaheer-ud-Ud-Khan 《云南植物研究》 CSCD 北大核心 2005年第6期676-684,共9页
An ex-situ experiment was conducted to evaluate the growth performance of six medicinal species (Bergenia ciliata,Valeriana jatamansi,Dioscorea deltoidea,Paeonia emodi,Polygonum amplexicaule and Viola serpense) from u... An ex-situ experiment was conducted to evaluate the growth performance of six medicinal species (Bergenia ciliata,Valeriana jatamansi,Dioscorea deltoidea,Paeonia emodi,Polygonum amplexicaule and Viola serpense) from upper Swat,Pakistan.Experiments were conducted at four different locations in the upper Swat valley at altitudes ranging from 1200 to 1900 m.a.s.l.The objectives were:1) to determine the suitability of ex-situ cultivation of different medicinal species,and;2) to assess the economic geasibility of growing medicinal plants in the area.A highest mean survival of 80.7% across all locations was observed for Viola serpense,followed by 58.7% for Valeriana jatamansi.The remaining four species exhibited very poor survival rates,although Polygonum amplexicaule,did show encouraging signs of growth and flowered,before experiencing high mortality rates late in the trial.Altitude generally seemed to enhance the degree of sprouting for all species except Viola serpense.However,the productive yield of V.serpense was certainly not reduced,but rather slightly enhanced in the higher altitude sites.Overall,cultivation of only two of the investigated species,Valeriana jatamansi and Viola serpense,appeared successful and potentially economically viable under farmland conditions at upper Swat. 展开更多
关键词 药用植物 巴基斯坦 种植技术 宽叶甘松 蓼属
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青藏高原东北缘濒危马麝迁地保育种群繁殖成效与社会性和社会网络的关系
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作者 周鑫 吕青昕 +4 位作者 桑珠扎西 扎西 周密 黎勇 孟秀祥 《生态学报》 CAS CSCD 北大核心 2024年第15期6417-6423,共7页
麝类驯养是濒危马麝(Moschus chrysogaster)迁地保育及保障药用麝香安全的重要方式,其前提和基础是深入了解制约迁地保育马麝繁殖成效的关键因素及与社会性和社会网络特征的关系。于2022年7月1日—8月31日期间,采用焦点取样和所有事件... 麝类驯养是濒危马麝(Moschus chrysogaster)迁地保育及保障药用麝香安全的重要方式,其前提和基础是深入了解制约迁地保育马麝繁殖成效的关键因素及与社会性和社会网络特征的关系。于2022年7月1日—8月31日期间,采用焦点取样和所有事件记录法对位于青藏高原东北缘的甘肃平凉马麝繁育中心的21头成年雌麝进行了社会性行为取样,辅以同期粪样类固醇代谢物水平检测,分析了马麝的繁殖成效与社会性、社会网络及粪样类固醇激素水平的关系。结果显示,马麝的社会性与繁殖成效间呈显著相关(r=0.551,P<0.05),与粪样皮质醇代谢物水平呈显著负相关(r=-0.437,P<0.05),与粪样雌二醇代谢物浓度相关不显著(r=0.066,P>0.05);强社会性马麝的皮质醇水平((10.75±0.99)ng/g)和雌二醇代谢物水平((6.61±0.79)ng/g)与弱社会性马麝((13.70±1.68,5.20±0.99)ng/g)无显著差异(P>0.05);繁殖成功雌麝的社会性(19.86±1.88)%)显著高于繁殖失败雌麝(12.38±1.46)%)(P<0.05);圈群社会网络密度与圈群个体的繁殖成效相关显著(r=0.762,P<0.05),与粪样皮质醇、雌二醇代谢物浓度相关不显著(r=-0.355,P>0.05;r=-0.347,P>0.05);繁殖成功雌麝的粪样皮质醇代谢物浓度((10.31±0.86)ng/g)略低于繁殖失败雌麝((13.98±1.60)ng/g)(r=-0.420,P=0.058),繁殖成功雌麝的粪样雌二醇代谢物浓度((6.63±0.90)ng/g)与繁殖失败雌麝((4.78±0.76)ng/g)无显著相关(r=0.299,P>0.05)。本研究结果表明,在群居性的迁地保育和驯养环境下,雌性马麝的社会性、社会网络属性可以预测个体的繁殖成效,即社会性和社会网络密度较高圈群中的雌麝的繁殖成效相对较高。濒危马麝保育和驯养实践中,可区分麝类驯养为“保育性驯养”和“商业性驯养”。在保育性驯养中,可采用先群居再独居驯养的模式,尽量保持野外放归马麝的自然行为结构;在商业性养殖中,可采用群居驯养模式,提升驯养麝的社会性,实现较高的繁殖成效和驯养生产力。 展开更多
关键词 迁地保育 马麝(Moschus chrysogaster) 平凉马麝繁育中心 社会性和社会网络 繁殖成效
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国家公园和国家植物园的自然教育 被引量:1
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作者 任海 《国家公园(中英文)》 2024年第1期1-6,共6页
国家公园和国家植物园分别是开展就地保护和迁地保护的重要机构,国家公园和国家植物园可以开展基于保护的科学研究、资源利用和自然教育,国家公园和国家植物园的自然保护也可以促进保护、科学研究和资源利用工作。国家公园和国家植物园... 国家公园和国家植物园分别是开展就地保护和迁地保护的重要机构,国家公园和国家植物园可以开展基于保护的科学研究、资源利用和自然教育,国家公园和国家植物园的自然保护也可以促进保护、科学研究和资源利用工作。国家公园和国家植物园基于整合保护的自然教育,是公益性的体现,也为保护等其他功能的实现提供基础条件。国家公园和国家植物园需要形成以生物多样性保护为主题的自然教育的知识传播、科学精神、科学文化和科学探究体系,将植物文化与科学文化、民族文化、时代精神深度融合,探索高端保护和科研资源科普化的自然教育新模式,在自然教育中有效渗透科学教育,促进受众的价值观从“人类中心主义”向“生态整体主义”转变,为履行昆明-蒙特利尔生物多样性框架以及建设人与自然和谐共生现代化的生物多样性保护、恢复和利用以及自然教育发挥重要作用。 展开更多
关键词 就地保护 迁地保护 环境教育 整合保护
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生态文明研究方法论:变焦与在场
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作者 刘华杰 《北京林业大学学报(社会科学版)》 2024年第3期17-23,共7页
“生态文明”已经成为一个学术热词,这既是好事也值得警惕。人文学者从事生态文明、生物多样性研究,通常视角较为单一,两手干干净净,只是坐而论道。从方法论上看,对于前者,需要考虑“变焦方法”,即在不同的尺度上考察问题。对于后者,人... “生态文明”已经成为一个学术热词,这既是好事也值得警惕。人文学者从事生态文明、生物多样性研究,通常视角较为单一,两手干干净净,只是坐而论道。从方法论上看,对于前者,需要考虑“变焦方法”,即在不同的尺度上考察问题。对于后者,人文学者宜深入实际,先弄脏自己,多进行“在场哲学”研究。中国有一系列值得关注的生态、环境、生物多样性破坏案例,人文学者可对其进行有益的分析。“迁地保护”事件依然值得追踪,它是科学界、园艺界长期惯性思维的一个突出表现。 展开更多
关键词 生态文明 变焦方法 在场哲学 迁地保护
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古槐迁地保护移植关键技术及复壮研究 被引量:2
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作者 何军 刘宝强 +5 位作者 聂亚芳 汤毅 程国兵 赵海明 李振星 高发明 《浙江林业科技》 2024年第1期72-79,共8页
古树保护性移植是一项综合性、系统性的工程,其移植技术含量高,操作难度大,各工作环节都要严格遵循正确的操作技术流程。总结了2022年12月中旬至2023年1月中旬对北京市东城区两株古槐Sophora japonica移植前的现场调研、人员和材料准备... 古树保护性移植是一项综合性、系统性的工程,其移植技术含量高,操作难度大,各工作环节都要严格遵循正确的操作技术流程。总结了2022年12月中旬至2023年1月中旬对北京市东城区两株古槐Sophora japonica移植前的现场调研、人员和材料准备、树木雷达波探根、应力波枝干空洞检测、新型井字形工字钢托架吊运以及移植后复壮等关键技术要点,保证了古槐移植的成活及施工安全。结果表明,移植前的充分准备、先进诊断技术及可操作性强的施工工艺,是保证古槐移植成功的关键,为古树依法迁地保护提供重要的技术参考。 展开更多
关键词 古槐 迁地保护 移植 复壮
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黑臭水体底泥处理技术发展现状 被引量:1
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作者 李涛 龚逸 +3 位作者 蔡浩瀚 刘才生 王宗平 谢鹏超 《水处理技术》 CAS CSCD 北大核心 2024年第4期8-11,31,共5页
我国河湖黑臭水体问题极大地影响了生态环境系统,并对人体健康和经济发展构成威胁。目前随着我国大力推进黑臭水体治理,截污系统逐渐完善,底泥中污染物释放及在厌氧环境下发酵产生的嗅味物质引发的内源污染成为了河湖黑臭的重要原因。因... 我国河湖黑臭水体问题极大地影响了生态环境系统,并对人体健康和经济发展构成威胁。目前随着我国大力推进黑臭水体治理,截污系统逐渐完善,底泥中污染物释放及在厌氧环境下发酵产生的嗅味物质引发的内源污染成为了河湖黑臭的重要原因。因此,黑臭水体底泥治理成为了水环境治理领域的热点和难点,目前针对黑臭水体底泥的主要处理方法有异位修复和原位修复两大类。本文针对黑臭水体底泥的成因、组成及危害做出分析,系统阐述了异位修复技术和原位修复技术的分类、原理及各处理技术的利弊,并对底泥修复技术的发展做出展望,明确了原位修复技术的巨大发展空间。 展开更多
关键词 黑臭水体底泥 异位处理技术 原位处理技术 环境风险
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地下水污染修复技术及其国内工程应用进展 被引量:1
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作者 吴汾奇 祝凯 +3 位作者 马偲尧 胡伟 王林 李燕 《科技通报》 2024年第3期1-8,27,共9页
地下水污染具有长期性、隐蔽性、难恢复性等特点,开展地下水污染场地的修复工作是一项巨大的挑战。对此,国内外研究团队提出了多种修复技术,但如何选择适用于我国地下水污染场地的技术或技术组合,对我国地下水污染治理具有重要意义。本... 地下水污染具有长期性、隐蔽性、难恢复性等特点,开展地下水污染场地的修复工作是一项巨大的挑战。对此,国内外研究团队提出了多种修复技术,但如何选择适用于我国地下水污染场地的技术或技术组合,对我国地下水污染治理具有重要意义。本文对常用修复技术在我国的工程应用情况进行调查整合,并从技术原理、场地水文地质条件的适用范围及工程应用效果等方面对其进行具体探讨,综述了地下水污染场地修复技术筛选常用方法,希望为我国地下水污染场地修复提供些许参考。 展开更多
关键词 地下水污染 原位修复技术 异位修复技术 自然衰减
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植物园迁地保护环境下纹瓣兰的繁殖生物学研究 被引量:1
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作者 施嘉雯 钱永辉 +1 位作者 罗艳 李青青 《热带亚热带植物学报》 CAS CSCD 北大核心 2024年第3期397-408,共12页
深入了解濒危物种的繁殖特性,能为物种制定有效保护策略提供科学依据。于2022和2023年对中国科学院西双版纳热带植物园迁地保存的纹瓣兰(Cymbidium aloifolium)的繁殖生物学特征进行了观察和研究,主要包括开花物候、繁育系统、花部形态... 深入了解濒危物种的繁殖特性,能为物种制定有效保护策略提供科学依据。于2022和2023年对中国科学院西双版纳热带植物园迁地保存的纹瓣兰(Cymbidium aloifolium)的繁殖生物学特征进行了观察和研究,主要包括开花物候、繁育系统、花部形态特征、昆虫传粉特征以及花的挥发性成分等。结果表明,纹瓣兰的盛花期在4月中旬,单花花期7 d;群体花期约为36d。花粉活力在开花第1天时最高,约为47.15%,之后呈下降趋势。柱头在整个单花期一直具可授性,开花第2天可授性最强。人工授粉实验表明纹瓣兰自交亲和,不存在无融合生殖和自动自花授粉,繁育系统属于兼性异交繁育并依赖传粉者,自然结实率较低为6.9%。唇瓣的先端和基部的表皮细胞分别为锥形和指状突起,基部的指状突起细胞外附着有油脂颗粒,可能是传粉者的报酬。药帽黄色,其表皮细胞为锥形细胞,能够反射光线,可能起到吸引昆虫的作用,中华蜜蜂(Apis cerana)是纹瓣兰唯一的有效传粉昆虫。纹瓣兰的挥发性气味中(E)-乙酸-2-癸烯-1-醇酯含量最高。因此,纹瓣兰的花部结构与传粉昆虫具有显著的适应性。 展开更多
关键词 迁地保护 纹瓣兰 花部特征 繁育系统 传粉特征 中华蜜蜂
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纳米FeSe_(2)正极材料制备与镁电池中性能表征
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作者 王利诚 徐昊 +1 位作者 李钊 邹建新 《电源技术》 CAS 北大核心 2024年第4期725-731,共7页
采用溶剂热法,利用表面活性剂的分散作用成功合成了FeSe_(2)纳米颗粒,将其作为正极材料组装可充镁电池,并进行电化学性能测试。结果显示,FeSe_(2)正极在100 mA/g电流密度下首次放电比容量为119 mAh/g,并在循环过程中展现出比容量的逐渐... 采用溶剂热法,利用表面活性剂的分散作用成功合成了FeSe_(2)纳米颗粒,将其作为正极材料组装可充镁电池,并进行电化学性能测试。结果显示,FeSe_(2)正极在100 mA/g电流密度下首次放电比容量为119 mAh/g,并在循环过程中展现出比容量的逐渐升高,在循环48次后获得最大放电比容量628 mAh/g,同时具有良好的循环稳定性,在100次循环后仍保持581 mAh/g的放电比容量。非原位TEM、XPS和同步辐射软X射线吸收谱分析表明,FeSe_(2)正极在循环过程中,铜集流体会参与正极电化学反应并形成含铜化合物,在正极材料中形成导电通路,这有利于电化学反应过程中电子的转移。因此,FeSe_(2)纳米颗粒充分参与正极转化反应,并展现出高容量和长循环稳定性,为镁电池中的集流体和硒族化合物的匹配性设计提供了新的思路。 展开更多
关键词 可充镁电池 正极材料 FeSe_(2) 铜集流体 非原位表征
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电池储能系统状态估计综述
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作者 孙玉树 龚一莼 +4 位作者 董亮 王晓晨 闫月君 唐西胜 党艳阳 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第6期2320-2333,共14页
为了提高多场景应用的技术经济性,本文对电池储能系统状态估计进行了综述。首先,分析了电池性能衰减的机理,介绍了目前常用的物理建模和数据建模方法,进而对荷电状态(state of charge,SOC)和健康状态(state of health,SOH)进行了定义与... 为了提高多场景应用的技术经济性,本文对电池储能系统状态估计进行了综述。首先,分析了电池性能衰减的机理,介绍了目前常用的物理建模和数据建模方法,进而对荷电状态(state of charge,SOC)和健康状态(state of health,SOH)进行了定义与关联性分析,并对电池及其系统的状态估计方法进行了汇总;其次,为了获取更多精确的电池运行数据,重点介绍了能够刻画电池内部演化机理的原位/非原位表征技术,进而分析了嵌入式电池管理系统(battery management system,BMS)实际应用的主流开发路线;第三,提出了基于联邦学习的电池储能系统状态估计方法,基于轻量化模型在本地进行电池储能系统SOC的估计以保证控制实时性,基于大数据驱动策略在云中心进行其SOH估计以保证容量可信度,由此实现云边的交互与协同;最后,对电池储能系统未来可能的发展方向和研究重点进行了预测。研究结果表明:活性锂损失是锂离子电池容量衰退的主要原因,高温、低温、过充放等滥用也会加速电池性能衰减;数据驱动在电池系统级建模与状态评估方面具有较大优势;利用原位/非原位表征技术可以获取更多的电池内部状态数据,基于FPGA的BMS轻量化建模更易实现,基于联邦学习的状态评估方法能够提高电池储能系统的智慧化运维水平。 展开更多
关键词 电池储能系统 性能衰减机理 状态估计 原位/非原位表征技术 轻量化BMS 联邦学习
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面向高比能固态电池的聚合物基电解质固化技术 被引量:3
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作者 李卓 郭新 《储能科学与技术》 CSCD 北大核心 2024年第1期212-230,共19页
聚合物基电解质是最具应用前景的固体电解质,它可以在很大程度上缓解甚至解决二次电池中电解液的泄漏、挥发、燃烧和爆炸等潜在安全问题。但是,聚合物基电解质的制备涉及到从液体到固体的固化过程,通常存在工艺烦琐、排放高、厚度难以... 聚合物基电解质是最具应用前景的固体电解质,它可以在很大程度上缓解甚至解决二次电池中电解液的泄漏、挥发、燃烧和爆炸等潜在安全问题。但是,聚合物基电解质的制备涉及到从液体到固体的固化过程,通常存在工艺烦琐、排放高、厚度难以控制等问题。特别是在规模化生产高比能固态电池过程中,电解质的界面相容性、均匀性、厚度及制备/加工便利性十分重要,这些因素对聚合物基电解质的固化工艺来说是一个较大的挑战。基于此,本文全面总结了聚合物基电解质制备的非原位固化和原位固化两种固化工艺的具体方法,并通过实例重点阐述了固化工艺、固化机理、材料选择、固化工艺优缺点及其在锂二次电池中的应用和研究进展。最后,我们评估并展望了面向高比能固态电池的聚合物基电解质固化的关键材料选择、关键科学及工艺问题、普适性、规模化应用挑战和未来发展趋势。本综述有助于深入理解面向高比能固态电池的聚合物基电解质的固化工艺,有望促进聚合物基电解质及其固态电池的规模化生产和应用。 展开更多
关键词 聚合物基电解质 原位固化技术 非原位固化技术 固态电池 材料选择
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