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A revision of Clematis sect.Atragene(Ranunculaceae) 被引量:3
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作者 Wen-Jing YANG Liang-Qian LI Lei XIE 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第6期552-580,共29页
Clematis sect. Atragene is revised in this paper based on the examination of a large number of herbarium specimens, extensive field observations, and morphometric analyses. Brief taxonomic history and geographical dis... Clematis sect. Atragene is revised in this paper based on the examination of a large number of herbarium specimens, extensive field observations, and morphometric analyses. Brief taxonomic history and geographical distribution of the section are given, the relationships among the species are discussed, and the evolutionary trends of some characters in the section are evaluated. The staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing anthers. Subsequently, they may have evolved in two different ways. One possibility is that the staminodes elongate and become lanceolate, as long as sepals, and their apices turn into attenuate. The other is that the staminodes are spathulate, but not elongating, as long as stamens, and their apices turn into retuse from obtuse and rounded. The evolutionary trend of sepals may be from thin to thick in texture, and the veins from non-prominent to prominent. As a result, five new series are established and nine species, two subspecies and nine varieties (including three new ranks) are recognized in this section. An identification key is provided, and each taxon is described and illustrated. Clematis sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of, or few, overlapping distributions. Clematis fusijamana and Clematisfauriei are recognized as varieties of C. alpina ssp. ochotensis for the continuous variation of the velutinous strips on the sepal margins. Clematis iliensis is treated as variety of C. alpina ssp. sibirica for the continuous variation of leaf division types. Extensive variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis koreana. The North American ser. Occientales may be primitive, whereas ser. Macropetalae may be the most advanced taxon in this section. Ser. Alpinae and ser. Koreanae are closely related to each other. However, the systematic position of ser. Tomentosae cannot be determined based on morphological characters alone in the present study. 展开更多
关键词 clematis sect. Atragene RANUNCULACEAE taxonomic revision.
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A revision of Clematis sect. Aspidanthera s.l. (Ranunculaceae) 被引量:3
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作者 WANG Wen-Tsai 《植物分类学报》 CSCD 北大核心 2004年第1期1-72,共72页
In this paper Clematis sect. Aspidanthera s.l. is revised. Seventy_ two species and 15 varieties are recognized. They are keyed, described, and in most cases illustrated, and are classified into six subsections. Of th... In this paper Clematis sect. Aspidanthera s.l. is revised. Seventy_ two species and 15 varieties are recognized. They are keyed, described, and in most cases illustrated, and are classified into six subsections. Of them, on e series, five species, and two varieties are described as new, and two new rank s are proposed. Brief taxonomic history and geographical distribution of the sec tion are given, the evolutionary trends of several important morphological characters observed are e numerated, and the relationships of its subsections are discussed. As a resul t, subsect. Dioicae, which shows striking resemblance in both habit an d floral structure to sect. Clematis subsect. Clematis, is regar ded as t he primitive group, while subsect. Insidiosae, bearing pistillate flower wit h erect sepals and no staminodes, is regarded as the advanced group within the s ection. 展开更多
关键词 铁线莲 毛茛科 植物分类学
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基于Adh基因家族序列的牡丹组(Sect.MoutanDC.)种间关系 被引量:38
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作者 林启冰 周志钦 +2 位作者 赵宣 潘开玉 洪德元 《园艺学报》 CAS CSCD 北大核心 2004年第5期627-632,共6页
测定了牡丹组 7个种 10个野生居群共 10份样品的全部Adh1A、Adh1B和Adh2基因序列。结合前人已报道的牡丹野生种的Adh基因序列 ,以芍药组 (Sect .Paeonia)和北美芍药组 (Sect.Oneapia)的种作外类群 ,用PAUP (4 0b 4a)计算机程序构建了... 测定了牡丹组 7个种 10个野生居群共 10份样品的全部Adh1A、Adh1B和Adh2基因序列。结合前人已报道的牡丹野生种的Adh基因序列 ,以芍药组 (Sect .Paeonia)和北美芍药组 (Sect.Oneapia)的种作外类群 ,用PAUP (4 0b 4a)计算机程序构建了牡丹组全部 8个种的Adh1A、Adh1B和Adh2基因树 (最大简约树和邻接树 ) ,同时进行了Adh1A、Adh1B和Adh2基因序列的合并分析。结果表明 ,牡丹组的 8个种分为两个具有 90 %以上自展值支持的单系分支 ,分别对应Stern (194 6 )根据形态划分的革质花盘亚组 (Subsect .Vaginatae)和肉质花盘亚组 (Subsect.Delavayanae)。在革质花盘亚组内 ,本研究结果支持银屏牡丹 (Paeoniasuffruticosassp .yinpingmudan)和凤丹 (P .ostii)、紫斑牡丹 (P .rockii)和四川牡丹 (P .decomposita)以及矮牡丹 (P .jishanensis)和卵叶牡丹 (P .qiui)各种之间有更近的亲缘关系 ,但有关牡丹复合体 (P .suffruticosacomplex)内各种间更进一步的关系还有待进一步研究。根据Adh基因树并结合前人的结果对牡丹组的种间关系进行了详细的讨论。 展开更多
关键词 Adh基因家族 基因序列 牡丹组 sect.MoutanDC. 种间关系
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Flavanoids from Clematis hexapetala 被引量:14
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作者 董彩霞 武可泗 +1 位作者 史社坡 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第1期15-20,共6页
Aim To study the chemical constituents from the roots and rhizomes of Clematis hexapetala Pall.. Methods The components were isolated by means of solvent extraction, repeated chromatography with silica gel, sephadex L... Aim To study the chemical constituents from the roots and rhizomes of Clematis hexapetala Pall.. Methods The components were isolated by means of solvent extraction, repeated chromatography with silica gel, sephadex LH-20 and prep-HPLC. The structures were determined by spectrum analysis. Results Twelve flavonoids were isolated and their structures were identified as 3, 5, 6, 7, 8, 3', 4'-heptamethoxyflavone (1), nobiletin (2), liquiritigenin (3), hesperetin (4), naringenin (5), liquiritigen-7-O-β-D-glucopyranoside (6), 5,7, 4' -trihydroxy-3'- methoxyflavanone -7-O-α-L-rhamnopyranosyl ( 1→6 ) -β-D-glucopyranoside (7), 6-hydroxybiochain A ( 8), formononetin (9), daidzein (10), genistein (11), and tectoridin (12). Conclusion All the said compounds were isolated from the plant for the first time. 展开更多
关键词 clematis hexapetala Pall. FLAVONOIDS structure determination
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Leaf Epidermal Feature in Clematis (Ranunculaceae) with Reference to Its Systematic Significance 被引量:21
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作者 史京华 李良千 《Acta Botanica Sinica》 CSCD 2003年第3期257-268,共12页
For finding valuable systematic characters, leaf epidermis of 77 taxa, representing 12 sections of the genus Clematis and three related genera in the Ranunculaceae, were examined mainly by means of light microscop... For finding valuable systematic characters, leaf epidermis of 77 taxa, representing 12 sections of the genus Clematis and three related genera in the Ranunculaceae, were examined mainly by means of light microscopy (LM), and partially by scanning electron microscopy (SEM). It was shown that the leaf epidermal cells were usually irregular or polygonal in shape. The patterns of anticlinal walls were straight, arched or undulate. The stomatal apparatus is anomocytic and exists in abaxial epidermis of all species, and in the adaxial epidermis of some species. Under SEM observation, the leaf epidermis was often striated, seldom nearly smooth, and often with flakes attached. Evidence from leaf epidermis serves as a criterion for distinguishing the subsections in sect. Meclatis (Spach) Tamura and in sect. Fruticella Tamura. The results also support that there are several separate evolutionary processes in the genus Clematis . 展开更多
关键词 RANUNCULACEAE clematis leaf epidermis stomatal apparatus
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Circumscriptions and Phylogenetic Relationships of Primula Sects. Auganthus and Ranunculoides: Evidence from nrDNA ITS Sequences 被引量:3
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作者 郝刚 胡启明 李南淑 《Acta Botanica Sinica》 CSCD 2002年第1期72-75,共4页
The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. W... The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. We conducted a phylogenetic analysis using sequences from the ITS region of nuclear ribosomal DNA. All five species of these two sections and some representatives of other related sections were sampled. The ITS trees show that P. filchnerae could be convincingly placed in sect. Auganthus , together with P. sinensis Sabine ex Lindl. and P. rupestris Balf. f. et Farrer, whereas sect. Ranunculoides contains two species: P. cicutariifolia Pax and P. merrilliana Schltr. These two sections are distantly related and their association with other sections needs further studies. This study also demonstrated that ITS sequences would be a suitable marker for the reconstruction of Primula phylogeny. 展开更多
关键词 PRIMULA sect. Auganthus sect. Ranunculoides PHYLOGENY ITS PRIMULACEAE
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芍药属牡丹组(Paeonia sect.Moutan)种间关系的分子证据:GPAT基因的PCR-RFLP和序列分析 被引量:34
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作者 赵宣 周志钦 +2 位作者 林启冰 潘开玉 洪德元 《植物分类学报》 CSCD 北大核心 2004年第3期236-244,共9页
为了探讨芍药属牡丹组Paeoniasect.Moutan的种间关系 ,对采自 1 5个野生居群 ,代表牡丹组全部 8个野生种的 1 5份材料的GPAT基因片段 (外显子 5和 6之间 2kb的内含子 )进行了PCR_RFLP分析 ,并对代表牡丹组全部 8个野生种的 9份材料进行... 为了探讨芍药属牡丹组Paeoniasect.Moutan的种间关系 ,对采自 1 5个野生居群 ,代表牡丹组全部 8个野生种的 1 5份材料的GPAT基因片段 (外显子 5和 6之间 2kb的内含子 )进行了PCR_RFLP分析 ,并对代表牡丹组全部 8个野生种的 9份材料进行了测序。根据 1 2个限制性内切酶的PCR_RFLP数据 ,使用Network 3 .0计算机程序的RM (reduced_median)法建立了牡丹组种间亲缘关系网络树。同时根据 8个种 9份材料的GPAT基因片段序列 ,利用PAUP 4.0计算机程序建立了牡丹组GPAT基因的最大简约(MP)树和邻接 (NJ)树。结果获得了具有很高自展值支持、分辨良好的牡丹组种间关系 (GPAT基因 )树。最重要的是 ,该基因树所显示的牡丹组种间关系与根据形态学证据提出的牡丹组的种间关系基本吻合 ,并得到其他研究证据的支持。根据这一结果 ,对牡丹组的种间关系进行了详细的讨论。 展开更多
关键词 芍药属 牡丹组 野生居群 种间关系 GPAT基因 PCR-RFLP 序列分析
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知识联盟中的知识创新过程研究——对SECT模型的再认识 被引量:4
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作者 胡延平 刘晓敏 《经济与管理》 2008年第7期31-34,共4页
SECT模型只是对知识创新过程中的知识客体演变运动的轨迹进行刻画,而没有深入分析完成从知识转移到知识创新这一过程的主体——组织和个人进行知识创新的实际过程,同时,"场"理论中过于强调隐性只是与显性知识的区别,而没有看... SECT模型只是对知识创新过程中的知识客体演变运动的轨迹进行刻画,而没有深入分析完成从知识转移到知识创新这一过程的主体——组织和个人进行知识创新的实际过程,同时,"场"理论中过于强调隐性只是与显性知识的区别,而没有看到两者之间的联系,将知识创新过程分割地对应于不同阶段。基于不同等级和等级对知识划分,结合单环学习、双环学习与再学习的知识创新的一般过程,对SECT模型和"场"理论进行了修正,说明知识创新需经历SECT模型的不同阶段和相应"场"情景支持,但每阶段都会产生隐性知识和显性知识。 展开更多
关键词 知识创新 sect模型 “场”理论
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单叶铁线莲Clematis henryi愈伤组织诱导与植株再生 被引量:9
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作者 黄余磊 吕枷薪 +3 位作者 蒋明 李温平 张徐俞 邹清成 《浙江农业学报》 CSCD 北大核心 2011年第4期731-735,共5页
以单叶铁线莲老枝、嫩茎、叶片和叶柄为外植体,在附加各种激素的MS培养基上进行诱导培养,以探讨愈伤组织诱导和植株再生的条件。结果表明,嫩茎为最佳外植体,适用于愈伤组织的诱导,在MS+1.2 mg.L-16-BA+0.35 mg.L-1NAA培养基中,嫩茎的出... 以单叶铁线莲老枝、嫩茎、叶片和叶柄为外植体,在附加各种激素的MS培养基上进行诱导培养,以探讨愈伤组织诱导和植株再生的条件。结果表明,嫩茎为最佳外植体,适用于愈伤组织的诱导,在MS+1.2 mg.L-16-BA+0.35 mg.L-1NAA培养基中,嫩茎的出愈率为88.6%;MS+4.0 mg.L-1KT+0.4 mg.L-1NAA为最佳不定芽诱导培养基,不定芽发生率为90.0%;MS+0.04 mg.L-1NAA为最佳生根培养基,生根率达95.0%。 展开更多
关键词 单叶铁线莲 嫩茎 愈伤组织 植株再生
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铁线莲品种Clematis‘Bill MacKenzie’愈伤组织的诱导 被引量:6
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作者 马育珠 李林芳 +5 位作者 马玲玲 王淑安 汪庆 李亚 王鹏 杨如同 《北方园艺》 CAS 北大核心 2015年第24期94-97,共4页
以铁线莲Clematis‘Bill MacKenzie’优良单株的嫩茎为外植体,研究了不同灭菌时间、基本培养基类型对C.‘Bill MacKenzie’愈伤组织诱导的影响,并在初代愈伤诱导的基础上,研究了不同外源激素组合对C.‘Bill MacKenzie’愈伤组织诱导及... 以铁线莲Clematis‘Bill MacKenzie’优良单株的嫩茎为外植体,研究了不同灭菌时间、基本培养基类型对C.‘Bill MacKenzie’愈伤组织诱导的影响,并在初代愈伤诱导的基础上,研究了不同外源激素组合对C.‘Bill MacKenzie’愈伤组织诱导及状态的影响。结果表明:最佳的灭菌时间为12min;基本培养基类型为MS,诱导率为68.4%;不同的外源激素组合均能诱导出愈伤,但是愈伤状态不同,其中MS+1.0mg/L 6-BA+0.4mg/L IBA时愈伤状态最好。 展开更多
关键词 铁线莲 茎段 愈伤 诱导
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不同光照强度和光质对铁线莲品种繁星(Clematis‘nelly moser’)不定芽诱导和生长的影响 被引量:5
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作者 徐玲玲 丁朵朵 +2 位作者 陶贵荣 党悦方 郭斌 《光子学报》 EI CAS CSCD 北大核心 2013年第6期715-720,共6页
以铁线莲品种繁星(Clematis‘nelly moser’)的带节茎段为材料,研究不同光照强度和光质对铁线莲不定芽繁殖的影响.以MS为基本培养基(含有0.2mg/L 1-萘乙酸和2mg/L 6-苄氨基腺嘌呤),设置光照强度梯度为0、500、2 000、3 000和4 000Lux的... 以铁线莲品种繁星(Clematis‘nelly moser’)的带节茎段为材料,研究不同光照强度和光质对铁线莲不定芽繁殖的影响.以MS为基本培养基(含有0.2mg/L 1-萘乙酸和2mg/L 6-苄氨基腺嘌呤),设置光照强度梯度为0、500、2 000、3 000和4 000Lux的白光光照;用透明玻璃纸得到蓝(440nm)、绿(560nm)、红(650nm)3种光质,以白光为对照组,强度均为3 000Lux.结果表明:在光照强度为3 000Lux的白光光照下,不定芽的诱导效果最好,其诱导频率和每个外植体上不定芽的数量分别为100%和4.4,每个外植体上不定芽的平均高度为5.66cm,平均节数为4.6个;蓝光能够显著提高不定芽的诱导数量,是相同光强白光诱导数量的1.27倍,蓝光下不定芽SOD和CAT的最大值显著高于其它光质下的数值,且叶绿素a和b的比值最大. 展开更多
关键词 生物光学 铁线莲 激素 不定芽 光照强度 光质
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Comparison on Four Extraction Methods of Genomic DNA from Clematis fasciculiflora Franch 被引量:3
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作者 胡祎晨 孙正海 +3 位作者 王锦 李世峰 辛培尧 范萱 《Agricultural Science & Technology》 CAS 2011年第10期1420-1423,共4页
[Objective] This study aimed at comparing the four extraction methods of genomic DNA from Clematis fasciculiflora Franch and determining the optimal extraction method for extracting the genomic DNA from Clematis fasci... [Objective] This study aimed at comparing the four extraction methods of genomic DNA from Clematis fasciculiflora Franch and determining the optimal extraction method for extracting the genomic DNA from Clematis fasciculiflora Franch.[Method] Leavies of Clematis fasciculiflora Franch were used as materials for comparing the purity and concentration of extracted DNA and extracting time among the four extraction methods of genomic DNA including improved CTAB method Ⅰ,improved CTAB method Ⅱ,improved CTAB method Ⅲ and improved SDS method.[Result] The four extraction methods could all be successfully used for extracting the genomic DNA from Clematis fasciculiflora Franch.The purity of genomic DNA was the highest using improved CTAB method Ⅰ,with the longest extracting time;while the concentration of genomic DNA was the maximum using the improved SDS method,with the shortest extracting time and relatively low purity;the extracting time of improved CTAB method Ⅲ was the shortest.[Conclusion] This study had established the optimal extraction method for extracting the genomic DNA from Clematis fasciculiflora Franch and supported for the further research using molecular biological methods. 展开更多
关键词 clematis fasciculiflora Franch Extraction of genomic DNA Improved CTAB method Improved SDS method
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Fruit Anatomy of sect. Paracamellia with Reference to Their Significance of Germplasm Resources Exploitation 被引量:1
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作者 洪思思 张斯敏 +3 位作者 楼嘉 张薇 吕洪飞 廖芳蕾 《Agricultural Science & Technology》 CAS 2011年第5期643-646,共4页
[Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracam... [Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracamellia was investigated.And the main component of sect.Paracamellia in the genus Camellia was studied by MVSP software.[Result] The exocarp was thin;mesocarp was broad,having a large number of stone cells;endocarp was lignified,and separated easily from seed.The principle components analysis suggested that the distance between species was far,showing far relation;the current study did not support the formation of Camellia grijsii(C.grijsii)and Camellia yuhsienensis(C.yuhsienensis),Camellia shensiensis(C.shensiensis)should not be recognized as a variety of C.yuhsienensis.In addition,it also proved Ming's combining of Camellia confusa(C.confusa)and Camellia kissi(C.kissi)was unnatural.[Conclusion] The study provided theoretical basis for the development and application of sect.Paracamellia in the genus Camellia. 展开更多
关键词 Genus Camellia sect.Paracamellia Fruit anatomy Classification Germplasm resources
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Distribution of Sect.Thea (L.) Dyer in Yunnan Province
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作者 汪云刚 刘本英 +7 位作者 宋维希 马玲 蒋会兵 矣兵 唐一春 李友勇 孙雪梅 王平盛 《Agricultural Science & Technology》 CAS 2011年第7期1067-1070,共4页
Yunnan is not only the center of tea origination but also the center of tea evolution and variation.There is a broad distribution of Sect.Thea(L.) Dyer in Yunnan.This paper concerns the research progress of Sect.The... Yunnan is not only the center of tea origination but also the center of tea evolution and variation.There is a broad distribution of Sect.Thea(L.) Dyer in Yunnan.This paper concerns the research progress of Sect.Thea(L.) Dyer,reveals the distribution of Sect.Thea(L.) Dyer in Yunnan,and checks out the number and name of Sect.Thea(L.) Dyer in Yunnan,which will offer references for further study and application of tea plants. 展开更多
关键词 YUNNAN sect.Thea(L.) Dyer DISTRIBUTION Species and Variety
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基于meat grinder with SECT电路的50kJ电感储能型脉冲电源的研究 被引量:5
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作者 班瑞 于歆杰 +1 位作者 刘旭堃 李臻 《电工电能新技术》 CSCD 北大核心 2017年第12期53-58,共6页
电感储能型脉冲电源是目前电磁发射技术的研究热点,提升装置储能密度对于推动电感储能型脉冲电源的应用和研究具有重要意义。本文介绍了一种适用于电感储能型脉冲电源的名为meat grinder with SECT的新电路,并对该电路进行了详细的原理... 电感储能型脉冲电源是目前电磁发射技术的研究热点,提升装置储能密度对于推动电感储能型脉冲电源的应用和研究具有重要意义。本文介绍了一种适用于电感储能型脉冲电源的名为meat grinder with SECT的新电路,并对该电路进行了详细的原理分析,指出该电路兼具电流关断能力强和拓扑结构简单的优点。通过仿真将meat grinder with SECT和STRETCH meat grinder、STRETCH meat grinder with ICCOS这两种主流电路进行了性能比较,发现meat grinder with SECT电路在保持电气性能不变的同时,成本最低,体积最小。基于meat grinder with SECT电路,本文研制了50k J电感储能型脉冲电源并进行了试验测试,测试结果达到了预期目标。 展开更多
关键词 电感储能型脉冲电源 MEAT GRINDER with sect 电磁发射 脉冲电源
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中国茜草属sect.Oligoneura的形态计量学研究 被引量:1
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作者 杨丽娥 孟盈 +1 位作者 聂泽龙 孙航 《广西植物》 CSCD 北大核心 2017年第7期829-840,共12页
茜草属为茜草科模式属,全球约80种,中国有近一半的物种,是茜草属的重要分布中心,大部分隶属于sect.Oligoneura。但是,该组内各种间的形态特征错综复杂,依靠单个性状不易划定种间界限。该研究在全面衡量sect.Oligoneura组内各种间形态特... 茜草属为茜草科模式属,全球约80种,中国有近一半的物种,是茜草属的重要分布中心,大部分隶属于sect.Oligoneura。但是,该组内各种间的形态特征错综复杂,依靠单个性状不易划定种间界限。该研究在全面衡量sect.Oligoneura组内各种间形态特征的基础上,选取该组20种共171份标本,对其3个数量性状和28个定性性状进行聚类分析和主成分分析。结果表明:在主成分分析中,前3个主成分累积贡献率有46.88%,性状的累积贡献率增长并不明显,但该结果仍与聚类分析结果一致。对前3个主成分贡献较大的特征包括叶形(叶长宽比)、叶柄长度、叶脉、每轮叶片数和生活型等,这些形态性状也是该属传统分类学中重要的物种鉴定特征。该研究结果与分子系统发育结果基本一致,支持该组内ser.Chinenses、R.mandersii group、R.angustissima group和R.siamensis group类群的划分,但并不支持ser.Cordifoliae单独成系。sect.Oligoneura内除少数物种外,大部分物种界限均比较清晰。形态计量学研究为sect.Oligoneura甚至茜草属的物种鉴定与划分提供了重要的参考意义。 展开更多
关键词 茜草属 sect.Oligoneura 聚类分析 主成分分析
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Studies on the Chemical Components of Clematis chinensis 被引量:7
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作者 何明 张静华 胡昌奇 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期180-182,共3页
Two novel compounds, clemaphenol A and dihydro-4-hydroxy-5-hyroxymethyl-2(3H)-fura-none were isolated together with eight known compounds, isoferulic acid, b-sitosterol, daucosterol, 5-hy-droxymethyl-2-furancarboxalde... Two novel compounds, clemaphenol A and dihydro-4-hydroxy-5-hyroxymethyl-2(3H)-fura-none were isolated together with eight known compounds, isoferulic acid, b-sitosterol, daucosterol, 5-hy-droxymethyl-2-furancarboxaldehyde, 5-hydroxy-4-oxo-pentanoic acid, palmitic acid, linoleic acid and anemonin from the root of Clematis chinensis Osbeck. 展开更多
关键词 clematis chinensis Clemaphenol A Dihydro-4-hydroxy-5-hyroxymethyl-2(3H)-furanone
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Two Novel Antifungal Saponins from Tibetan Herbal Medicine Clematis tangutica 被引量:21
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作者 Zhi Zhi DU Na ZHU Yue Mao SHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第7期707-710,共4页
Antifungal assay-guided isolation of the ethanol extract of the aerial parts of Clematis tangutica yielded two novel triterpene saponins. Their structures were determined to be 3-O-a-L-arabinopyranosyl hederagenin 28... Antifungal assay-guided isolation of the ethanol extract of the aerial parts of Clematis tangutica yielded two novel triterpene saponins. Their structures were determined to be 3-O-a-L-arabinopyranosyl hederagenin 28-O-a-L-rhamnopyranosyl ester (1) and 3-O-b-D- glucopyranosyl(14)-a-L-arabinopyranosyl hederagenin 28-O-a-L-rhamnopyranosyl ester (2) on the basis of spectral data and chemical reactions. 展开更多
关键词 clematis tangutica triterpene saponins HEDERAGENIN antifungal assay.
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SECT法电伴热系统漏电压的理论分析 被引量:1
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作者 邹玉民 戴琳 《油气储运》 CAS 北大核心 1992年第6期51-53,共3页
1 前言 SECT法(集肤电流加热法)具有结构简单、安全可靠、热效率高、易于实现自动控制等优点,因而在长输管线的伴热上得到了广泛地应用。 SECT法伴热系统是将SECT法加热管直接焊接到主管线上。
关键词 电加热 供热系统 漏泄电流 sect
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槭叶铁线莲(Clematis acerifolia Maxim.)群落物种生态位研究 被引量:8
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作者 庞久帅 原阳晨 +3 位作者 周苗苗 任俊杰 高鹏 成克武 《生态学报》 CAS CSCD 北大核心 2022年第8期3449-3457,共9页
槭叶铁线莲(Clematis acerifolia)为太行山特有植物,但数量稀少且分布零散,其生存状况受到学者和政府部门的高度关注。本文通过对河北省易县葫芦峪沟谷新发现的槭叶铁线莲群落的典型样地调查,以物种重要值作为生态位计量指标,对各物种... 槭叶铁线莲(Clematis acerifolia)为太行山特有植物,但数量稀少且分布零散,其生存状况受到学者和政府部门的高度关注。本文通过对河北省易县葫芦峪沟谷新发现的槭叶铁线莲群落的典型样地调查,以物种重要值作为生态位计量指标,对各物种生态位宽度、生态位重叠和生态位相似性进行了定量分析,对槭叶铁线莲的生存安全状况进行了评估。结果表明:在调查样地中共记录到14科15属17种植物,群落物种组成较为简单,槭叶铁线莲在大部分调查样地中的重要值最大,占据优势地位,其他物种重要值相对较低;群落内所有物种中,槭叶铁线莲的生态位宽度最大(B_(i)=6.264),绒毛绣线菊(Spiraea dasyantha)次之(B_(i)=5.144),其他种类较小;所有物种组成的136个种对中,生态位完全重叠(Q_(ik)=1)、重叠程度较高(0.5≤Q_(ik)<1)和重叠程度较低(Q_(ik)<0.5)的种对比例分别为8.09%、16.91%和75.00%,生态位完全相似(C;=1)、相似程度较高(0.5≤C;<1)和相似程度较低(C;<0.5)的种对比例分别为8.09%、5.88%和86.03%,大部分物种之间生态位重叠程度和相似性都处于较低水平;槭叶铁线莲与其他物种构成的16个种对中,62.50%的种对生态位重叠程度较低(Q_(ik)<0.5),81.25%的种对生态位相似性程度较低(C;<0.5),反映出群落内各物种间对资源和空间的竞争较为温和,群落较为稳定,槭叶铁线莲在其分布生境中生存状况相对安全;本文研究表明,利用生态位分析方法可以作为珍稀濒危物种生存状态和安全风险评估的一种方法。 展开更多
关键词 生态位 槭叶铁线莲 重要值 生态位宽度 生态位重叠 生态位相似性
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