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欧美杨类新无性系苗期生长模型及灰色关联度分析 被引量:22
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作者 张俊生 刘建民 +4 位作者 杨久廷 甘作勋 邢德海 张连友 岳余林 《辽宁林业科技》 1997年第5期18-20,共3页
欧美杨类新无性系在我国北方地区表现良好。为了搞好推广栽培,提高经济效益,采用Logistic曲线方程与苗期生长的实测数据进行拟合验证,对影响苗木生长的温度、光照和降水量3方面因素进行灰色关联度分析。结果表明,欧美杨类... 欧美杨类新无性系在我国北方地区表现良好。为了搞好推广栽培,提高经济效益,采用Logistic曲线方程与苗期生长的实测数据进行拟合验证,对影响苗木生长的温度、光照和降水量3方面因素进行灰色关联度分析。结果表明,欧美杨类新无性系的苗期生长可用Logistic生长模型进行预测,降水量对苗高影响最大,光照对地径影响最大。 展开更多
关键词 欧美杨无性 苗期 生长模型 灰色关联度
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长江护岸林欧美杨无性系混合造林研究 被引量:1
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作者 傅军 钱滕 黄荣来 《浙江林学院学报》 CSCD 1999年第4期346-352,共7页
为提高长江护岸林的生长量, 减少虫害, 进行了杨树多系混合造林研究。结果表明: 沿江护岸林欧美杨多系混合造林较单系造林生长量和年利润率均提高15 % 以上, 天牛虫株率控制在3 % 以内; 选育出4 个优良无性系, 材积生长量较169 杨( 对... 为提高长江护岸林的生长量, 减少虫害, 进行了杨树多系混合造林研究。结果表明: 沿江护岸林欧美杨多系混合造林较单系造林生长量和年利润率均提高15 % 以上, 天牛虫株率控制在3 % 以内; 选育出4 个优良无性系, 材积生长量较169 杨( 对照) 提高18-4 % ~47-5 % 。对参试欧美杨无性系进行了生长阶段和生长等级的划分。表7 展开更多
关键词 河岸防护林 欧美杨无性 混合造林 防治
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欧美杂种山杨体细胞无性系变异的分析 被引量:9
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作者 詹亚光 齐凤慧 +1 位作者 高瑞馨 杨传平 《植物学通报》 CAS CSCD 北大核心 2006年第1期44-51,共8页
以成年欧美杂种山杨(Populustremula×P.tremuloides)优良无性系为材料,通过组织培养方法获得体细胞无性系,利用细胞学和分子生物学方法对其发生的变异进行研究。结果表明:用3.0mg.L-12,4-D诱导的再生植株的细胞染色体稳定性较差,... 以成年欧美杂种山杨(Populustremula×P.tremuloides)优良无性系为材料,通过组织培养方法获得体细胞无性系,利用细胞学和分子生物学方法对其发生的变异进行研究。结果表明:用3.0mg.L-12,4-D诱导的再生植株的细胞染色体稳定性较差,所检测的144个细胞中,变异的细胞中多数发生了染色体加倍,二倍体细胞数仅占36.81%。有些染色体还发生了形态变异,染色体加长,形成带有随体或长臂较长的大型染色体。用1.0mg.L-16-BA诱导再生植株中染色体数量稳定性介于对照和3.0mg.L-12,4-D诱导的再生植株之间,在观察的142个细胞中二倍体细胞占54.93%。再生植株的AFLP分析表明,由激素诱导的再生植株中,AFLP谱带发生了变化,表明发生了体细胞无性系分子水平变异。 展开更多
关键词 欧美杂种山杨 体细胞无性 染色体 AFLP
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浅析不同文化定势下的留学生在使用日语时产生的差异——以亚洲留学生和欧美留学生为对比
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作者 梁田 《科技视界》 2013年第31期155-155,172,共2页
掌握日语的留学生在和日本人交流的时候,多是以日本人使用的日语为基准,不断纠正和完善自己使用的日语。然而来自不同国家的留学生在用日语交谈的时候,就没有了一定的标准,受到不同文化圈思维定势的影响,各自呈现出一定的特征。本文就... 掌握日语的留学生在和日本人交流的时候,多是以日本人使用的日语为基准,不断纠正和完善自己使用的日语。然而来自不同国家的留学生在用日语交谈的时候,就没有了一定的标准,受到不同文化圈思维定势的影响,各自呈现出一定的特征。本文就这一现象展开调查论证,得出了一些结论。 展开更多
关键词 文化定势 欧美系 亚洲 对话差异
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Field test of new poplar clone in Shangdong Province
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作者 秦光华 姜岳忠 +1 位作者 乔玉玲 B.Nottola 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期225-229,共5页
Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and do... Poplar is one of the dominant tree species for the establishment of fast growing plantations in Shandong Province. Eighteen poplar clones belonging to Populus aigeiros section were introduced from Italy, Turkey and domestic regions. Populus deltoides cv. 慙ux?I-69/55 (I-69), which was widely used in Shandong Province, China, was taken as control clone (I-69). Following a randomized complete block design, seedling test and controlled afforestation trials were carried out at Juxian County, Caoxian County and Laiyang City. The results showed that the poplar clone (Populus ?euramericana cv. ?02/74?, namely 102/74, performed well both in terms of adaptability and growth rate. The mean height of 13.9 m (H), diameter at breast height of 18.0 cm (DBH) and volume growth of 0.1445 m3 (V) were 2.2 %, 21.6% and 52.9 % higher than those of I-69 (CK), respectively, at the age of 5 years at three experimental sites. Moreover, the clone can be propagated easily and showed high resistance to poplar disease, pest as well as salinity and had longer growing period. Furthermore, wood basic density and fiber length of new poplar clone (102/74) were as same as I-69 (CK). It was concluded that the selected clone (102/74) was ideal for the estab-lishment of fast-growing poplar plantations, especially for the pulpwood plantations in Shandong Province. 展开更多
关键词 POPLAR CLONES INTRODUCTION SELECTION
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海外模玩新品速览
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《中外玩具制造》 2023年第8期24-25,共2页
根据不同的标准,海外模玩可以分为日系、欧美系;可动、不可动;场景组合、人(兽)形、道具等等诸多类别。下面,小编就选取了部分近期模玩新品,以飨读者。
关键词 小编 欧美系
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Palynological characteristics of Kazakhstan Province of Carboniferous Euramerican Region 被引量:1
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作者 Maya V.Oshurkova 《Global Geology》 2012年第1期1-12,共12页
The paper presents results of palynological studies of the coal-bearing Carboniferous in Central Kazakhstan. A quantitative dynamics of major genera of miospores reflects an overall succession of the Carboniferous mio... The paper presents results of palynological studies of the coal-bearing Carboniferous in Central Kazakhstan. A quantitative dynamics of major genera of miospores reflects an overall succession of the Carboniferous miospore assemblages. Visean Serpukhovian assemblages are dominanted by Lophozonotriletes fuscatus, Acanthozonotriletes cristifer, A. inclusus, Punctatisporites glabratus, Crassispora ignorata, C. scrupea, Cyclobaculisporites trichacanthus, Lycospora breviapiculata, L. echinata and Vallatisporites decrescens. Rare Punctatisporites bertschoguriensis , Stenozonotriletes marginellus , Vallatisporites appilicatus , Verrucosisporites serobiculatus , Retieulatisporites caneellatus, Granulatisporites areuatus are recorded, which are not found in assemblages from overlying sediments. Bashkirian-Moseovian assemblages are dominated by Lyeospora subtriquetra, L. pusilla, Vallatisporites ciliaris, Apiculatisporis mollis, Cyelogranisporites testieulatus, Calamospora mierorugosa, Sehopfipollenites principalis, Psilohyrnena psiloptera, Florinites grandis and Granulatisporites piroformis miospores. Cristatisporites latispinus, Angulisporites didymus, Thymospora obseura and Torispora securis are also present, as well as single Apieulatisporis eurvispinus, Raistriekia inordinata, Marsupipollenites retroflexus, Entylissa eaperata, Potonieisporites grandis and Cordaitina sp. A similar succession of miospore assemblages is recorded in the Carboniferous deposits of Europe and North America, which allows carrying out correlations, despite an endemic characters of many species of Paleozoic miospores from the coal-bearing Carboniferous of the Kazakhstan Province in the Euramerian Paleofloristic Region. 展开更多
关键词 MIOSPORES CARBONIFEROUS BIOSTRATIGRAPHY Kazakhstan
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Design Issues for Linking Emissions Trading Schemes--A Qualitative Analysis for Schemes from Europe, Asia and North America
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作者 Sebastian R. Goers Barbara Pflaglmayer Martin J. Luger 《Journal of Environmental Science and Engineering(B)》 2012年第12期1322-1334,共13页
The paper focuses on links between the EU ETS (European Union Emissions Trading Scheme) and selected (domestic) greenhouse gas ETS (emissions trading schemes) from Asia and North America which could open up a pe... The paper focuses on links between the EU ETS (European Union Emissions Trading Scheme) and selected (domestic) greenhouse gas ETS (emissions trading schemes) from Asia and North America which could open up a perspective to keep the idea of emissions trading alive on a global scale and confront the actual uncertainty in future climate policy. The approach consists of investigating qualitatively the essential requirements of this alternative bottom-up approach. It is evaluated if variations or inconsistencies in the structure and design of domestic ETS as well as legal and institutional characteristics harm or facilitate the concept of linking with the EU ETS. The evaluation of systems leads to the exclusion of systems with voluntary character, relative caps, unrestricted borrowing and price caps from the group of potential linking candidates. 展开更多
关键词 European Emissions Trading Scheme international and domestic emissions trading LINKING post-Kyoto.
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整天打“八段锦”的,都是些什么年轻人?
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作者 刘鑫宇 《现代青年》 2023年第2期44-45,共2页
从“欧美系撸铁”到“国潮派养生”,八段锦误打误撞进入了年轻人的生活,却让他们意外找到了某种平静的状态。
关键词 八段锦 年轻人 欧美系 意外
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小车风云战
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作者 严绍健 徐雨(摄影) 《汽车杂志》 2011年第8期120-131,共12页
近来欧美系小车正当红,新POLO、MG3与爱唯欧加入战局,加上先前的新嘉年华,看谁能获得冠军。
关键词 欧美系小车 汽车种类 汽车设计 《汽车杂志》
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浅谈黄淮平原栽培意杨技术
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作者 张用宪 水平 《森林与人类》 2000年第1期35-35,共1页
关键词 意杨 黄淮平原 引种 栽培技术 欧美黑杨无性
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The Troubled Russia-China Partnership as a Challenge to the East Asian Peace
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作者 Pavel K. Baev Stein Tonnesson 《Fudan Journal of the Humanities and Social Sciences》 2017年第2期209-225,共17页
With the annexation of the Crimea and the engagement in confrontation with the West, Russia has embarked on a course of making the military force into a useful instrument of policy. Moscow has effectively sacrificed t... With the annexation of the Crimea and the engagement in confrontation with the West, Russia has embarked on a course of making the military force into a useful instrument of policy. Moscow has effectively sacrificed the goals of modernization and development for the sake of geopolitical ambitions. The question about the price of Russia's revisionist enterprise is relevant for many states that are not satisfied with the unfair and often discriminating rules of the world order, first of all China. Russia hopes to inspire other states dissatisfied with the "unipolar" world order to challenge the West more boldly, but the result of its assault on the prin- ciples of nonintervention and territorial integrity might work in the opposite way. The states of East Asia could take a good measure of the risk inherent to embarking on the course of projecting power at the expense of modernization and become even more committed than before to upholding their unique prosperity-producing peace. China has a vested interest in Russian internal stability and must be worried by the prospect of a post-Putin crisis. 展开更多
关键词 East Asia Peace Russia - China Conflict - Partnership
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