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考古磁学─磁学在考古中的应用 被引量:12
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作者 阎桂林 《物探与化探》 CAS CSCD 1996年第2期141-148,共8页
60年代质子磁力仪问世,磁力勘查成为探查古遗存空间分布的主要地球物理方法之一。同时,古地磁学的发展使磁性地层学成为确定古遗存、古人类化石时代的重要手段。随着第四纪沉积物磁性特征研究的深人,又为环境考古提供了新的途径。... 60年代质子磁力仪问世,磁力勘查成为探查古遗存空间分布的主要地球物理方法之一。同时,古地磁学的发展使磁性地层学成为确定古遗存、古人类化石时代的重要手段。随着第四纪沉积物磁性特征研究的深人,又为环境考古提供了新的途径。作者通过实践研究,认为以古遗存本身及所处的地层的磁性特征为基础,从磁学机制出发,可将上述空间、时间及环境考古诸方面有机结合起来,构成统一的考古磁学。文中以祥硕的数据、实例介绍了应用的效果,并阐述了具体的工作方法与技术。 展开更多
关键词 磁性地层学 磁法勘探 磁化率 考古
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论大灭绝后的幸存类型、复活效应与避难所 被引量:12
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作者 戎嘉余 詹仁斌 《地学前缘》 EI CAS CSCD 北大核心 2006年第6期187-198,共12页
大灭绝后生物的幸免实质上是对灾变恶化环境的忍耐和适应生存。幸存分子能提供大灭绝规模和残存机制的部分信息。历次大灭绝后的残存与复苏有不同的形式,不同生物类群和同一类群中的不同生物对大灭绝事件更有不同的应对策略。在识别奥... 大灭绝后生物的幸免实质上是对灾变恶化环境的忍耐和适应生存。幸存分子能提供大灭绝规模和残存机制的部分信息。历次大灭绝后的残存与复苏有不同的形式,不同生物类群和同一类群中的不同生物对大灭绝事件更有不同的应对策略。在识别奥陶纪末大灭绝后3种幸存类型(“扩增幸存型”、“减缩幸存型”和“复活型”)的基础上,文中进一步指出,“减缩幸存型”的研究有助于理解“复活型”的含义。复活效应的识别应建筑在较高质量的化石记录基础上,但实践中寻找真正的复活生物却非易事。复活分类单元并不一定反映大灭绝的强度,其数量是受许多条件限制的;不同的大灭绝事件对不同门类(或类群)的冲击程度不一样,其复活表现形式也各不相同;并非每次大灭绝、每种生物类别都发育复活分子的。因此,复活效应和复活生物在大灭绝过程中的意义比过去想象的小得多。分析复活现象须掌握全球、而非局部地区的资料。在灾变时期,典型、常见分子是识别一个动物群的标志,而稀有分子更有助于复活效应的研究。史前避难所包含古地理、古生态、古环境和宏演化四方面因素,其识别和确定需寻找尽可能多的证据。史前“减缩幸存型”研究可能会给当今生物界研究一个有益的启示,即“濒危种”不一定完全陷入“穷途末路”之境地,而是仍有续生(或复活)的可能。 展开更多
关键词 大灭绝 幸存生物 复活分子 避难所 孑遗分子
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湖南八面山银杉群落特征及其残遗性和保守性分析 被引量:8
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作者 苏乐怡 赵万义 +4 位作者 张记军 杨玉鹏 郭远飞 凡强 廖文波 《植物资源与环境学报》 CAS CSCD 北大核心 2016年第4期76-86,共11页
为了解中国特有孑遗植物银杉(CathayaargyrophyllaChunetKuang)的生存现状,对位于湖南八面山脚盆辽的银杉+南方铁杉也Tsugachinensisvar.tchekiangensis(Flous)ChengetL.K.Fu页+甜槠也Castanopsiseyrei(Champ.)Tutch.页-猴头杜鹃(Rhodod... 为了解中国特有孑遗植物银杉(CathayaargyrophyllaChunetKuang)的生存现状,对位于湖南八面山脚盆辽的银杉+南方铁杉也Tsugachinensisvar.tchekiangensis(Flous)ChengetL.K.Fu页+甜槠也Castanopsiseyrei(Champ.)Tutch.页-猴头杜鹃(RhododendronsimiarumHance)群落进行调查,分析其群落特征及种群年龄结构,比较分布在不同区域的6个银杉群落中种子植物属的分布区类型及其相似性系数;在此基础上,讨论了银杉群落的残遗性特征。结果显示:脚盆辽银杉群落共有维管植物66种,包括蕨类植物4种和种子植物62种(裸子植物4种、被子植物58种);该群落乔木层的主要优势种为甜槠、猴头杜鹃、银杉和南方铁杉,重要值分别为13.12%、9.28%、8.86%和7.49%;该群落的Simpson和Shannon-Wiener多样性指数分别为0.94和3.20,Pielou均匀度指数Jsw和Jsi分别为0.81和0.92,说明该群落物种多样性偏低但物种分布均匀,与中亚热带山地的暖性针阔叶混交林特征一致。从生活型谱看,该群落中各频度百分比由高至低依次为A级、B级、C级、D级、E级,与Raunkiaer标准频度图谱基本一致,表明该群落整体上处于较为稳定的亚顶极状态。从银杉种群年龄结构看,种群中幼龄个体占一定比例,但80~180a的中龄个体比例偏低;从该群落优势种的径级结构看,甜槠、猴头杜鹃和鹿角杜鹃(RhododendronlatoucheaeFranch.)种群为增长型种群,而银杉、南方铁杉和福建柏也Fokieniahodginsii(Dunn)HenryetThomas页种群为衰退型种群。从脚盆辽银杉群落种子植物属的分布区类型看,温带分布型属占51.06%,略高于热带分布型属(占48.94%),说明该区域属于热带亚热带过渡区;除纬度外,海拔也能够在一定程度上影响其分布区类型组成。在处于粤北、粤桂山地和贵州高原3个植物区系亚地区的6个银杉群落中,种子植物属分布区类型的相似性系数为0.35~0.67,群落建群种所在属如铁杉属也Tsuga(Endlicher)Carri侉re 展开更多
关键词 湖南八面山脚盆辽 银杉 群落特征 分布区类型 种群年龄结构 残遗性
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A possible relict mantle wedge: Geochemical evidence from Paleogene volcanics in North China 被引量:3
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作者 Bolin Cong Jinghui Guo Wenjun Liu 《Chinese Science Bulletin》 SCIE EI CAS 2001年第22期1917-1922,共6页
The major and trace element and isotopic composition were analyzed for the Paleogene volcanics in North China dated by the K-Ar method. The geochemical data show that most volcanics are in calc-alkaline series and the... The major and trace element and isotopic composition were analyzed for the Paleogene volcanics in North China dated by the K-Ar method. The geochemical data show that most volcanics are in calc-alkaline series and the minor is in alkaline series. They differ obviously from Neogene and Quaternary volcanics in geochemistry. In particular, the Paleogene volcanics from the southern part of North China were derived from enriched lithospheric mantle (EMU), which were likely to be a relict mantle wedge formed during the subduction of the Yangtze plate into the North China plate in late Triassic (Indo- Sinian). 展开更多
关键词 VOLCANICS relict MANTLE WEDGE geochemistry PALEOGENE North China.
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A winged relative of ice-crawlers in amber bridges the cryptic extant Xenonomia and a rich fossil record 被引量:1
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作者 Yingying Cui Jeremie Bardin +8 位作者 Benjamin Wipfler Alexandre Demers-Potvin Ming Bai Yi-Jie Tong Grace Nuoxi Chen Huarong Chen Zhen-Ya Zhao Dong Ren Olivier Béthoux 《Insect Science》 SCIE CAS CSCD 2024年第5期1645-1656,共12页
Until the advent of phylogenomics,the atypical morphology of extant represen-tatives of the insect orders Grylloblattodea(ice-crawlers)and Mantophasmatodea(gladi-ators)had confounding effects on efforts to resolve the... Until the advent of phylogenomics,the atypical morphology of extant represen-tatives of the insect orders Grylloblattodea(ice-crawlers)and Mantophasmatodea(gladi-ators)had confounding effects on efforts to resolve their placement within Polyneoptera.This recent research has unequivocally shown that these species-poor groups are closely related and form the clade Xenonomia.Nonetheless,divergence dates of these groups re-main poorly constrained,and their evolutionary history debated,as the few well-identified fossils,characterized by a suite of morphological features similar to that of extant forms,are comparatively young.Notably,the extant forms of both groups are wingless,whereas most of the pre-Cretaceous insect fossil record is composed of winged insects,which represents a major shortcoming of the taxonomy.Here,we present new specimens em-bedded in mid-Cretaceous amber from Myanmar and belonging to the recently described species Aristovia danili.The abundant material and pristine preservation allowed a de-tailed documentation of the morphology of the species,including critical head features.Combined with a morphological data set encompassing all Polyneoptera,these new data unequivocally demonstrate that A.danili is a winged stem Grylloblattodea.This discov-ery demonstrates that winglessness was acquired independently in Grylloblattodea and Mantophasmatodea.Concurrently,wing apomorphic traits shared by the new fossil and earlier fossils demonstrate that a large subset of the former Protorthoptera"assemblage,representing a third of all known insect species in some Permian localities,are genuine representatives of Xenonomia.Data from the fossil record depict a distinctive evolution-ary trajectory,with the group being both highly diverse and abundant during the Permian but experiencing a severe decline from the Triassic onwards. 展开更多
关键词 Grylloblattodea INSECT Mantophasmatodea MESOZOIC Polyneoptera relict
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Forest characteristics and population structure of Glyptostrobus pensilis, a globally endangered relict species of southeastern China 被引量:2
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作者 Cindy Q. Tang Yongchuan Yang +14 位作者 Arata Momohara Huan-Chong Wang Hong Truong Luu Shuaifeng Li Kun Song Shenhua Qian Ben LePage Yi-Fei Dong Peng-Bin Han Masahiko Ohsawa Buu Thach Le Huu Dang Tran Minh Tri Dang Ming-Chun Peng Chong-Yun Wang 《Plant Diversity》 SCIE CAS CSCD 2019年第4期237-249,共13页
The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. F... The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam. 展开更多
关键词 Age-class Fujian Province Glyptostrobus Regeneration relict plant VIETNAM
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Subduction age of Neo-Tethys oceanic crust in southwest Yunnan, China: Laser micro-area ^(40)Ar-^(39)Ar dating 被引量:2
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作者 ZHOIMG Dalai, Jl Jianqing and HU ShilingInstitute of Geology, Chinese Academy of Sciences , Beijing 100029, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第23期2196-2199,共4页
The basic granulite, which is considered to be the MORB based on geochemistry and isotopic characteristics[1], has been discovered recently as the enclaves in the Yingjiang island-arc magmatic suite on the border of B... The basic granulite, which is considered to be the MORB based on geochemistry and isotopic characteristics[1], has been discovered recently as the enclaves in the Yingjiang island-arc magmatic suite on the border of Burma and west Yunnan, east of Myitkyina suture in the eastern Burma. The laser micro-area 40Ar-39Ar technique is used to date the age of garnet 展开更多
关键词 LASER micro-area 40Ar-39Ar DATING granulite facies metamorphic oceanic crust relict NEO-TETHYS SUBDUCTION age.
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Ether as the Fundamental Substance of the Creation of the Universe
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作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2023年第12期3800-3825,共26页
The paper analyzes the concept of Ether and substantiates the necessity of its existence as a physical reality, which arises within the framework of the concept developed by the authors of the work. The authors come t... The paper analyzes the concept of Ether and substantiates the necessity of its existence as a physical reality, which arises within the framework of the concept developed by the authors of the work. The authors come to the conclusion that the existence of Ether in two different forms, plays an exceptional role in the formation of Dark Matter and Dark Energy and leads to the emergence of exotic cosmological structures and their hierarchy in energy, temporal, and spatial scale. The mechanism of the formation of physical structures before the Big Bang and their further evolution, up to the formation of worlds of galaxies and stars, is considered. The necessity of the emergence of exotic structures, such as 3 spheres of the Primary Relict, is shown, its structure and dynamic properties leading to the formation of Order from Chaos are considered. The role of the 1st and 2nd type Ether in the formation of the mechanism of transformation of cosmic energies and quantum phase transitions, in the process of the birth and evolution of the Universe is discussed. The conclusion is made about the existence of universal properties of matter, at the level of Macro and Microcosms, and a multidimensional cosmological model with an isothermal temperature distribution is constructed, leading to a discrete distribution of matter separated by transitions, by analogy with Black-and-White Holes. It is shown that the postulate of the constancy of the speed of light in any inertial system is a consequence of the principle of covariance. 展开更多
关键词 ETHER Speed of Light Black and White Hole Quantum Transitions Primary relict Chaos and Order Primary Atom Big Bang Dark Matter and Energy Borromeo Rings
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Effects of taxon sampling on molecular dating for within-genus divergence events,when deep fossils are used for calibration 被引量:1
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作者 Richard I.MILNE 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期383-401,共19页
A universal method of molecular dating that can be applied to all families and genera regardless of their fossil records, or lack thereof, is highly desirable. A possible method for eudicots is to use a large phylogen... A universal method of molecular dating that can be applied to all families and genera regardless of their fossil records, or lack thereof, is highly desirable. A possible method for eudicots is to use a large phylogeny calibrated using deep fossils including tricolpate pollen as a fixed (124 mya) calibration point. This method was used to calculate node ages within three species-poor disjunct basal eudicot genera, Caulophyllum, Podophyllum and Pachysandra, and sensitivity of these ages to effects such as taxon sampling were then quantified. By deleting from one to three accessions related to each genus in 112 different combinations, a confidence range describing variation due only to taxon sampling was generated. Ranges for Caulophyllum, Podophyllum and Pachysandra were 8.4-10.6, 7.6-20.0, and 17.6-25.0 mya, respectively. However, the confidence ranges calculated using bootstrapping were much wider, at 3-19, 0-32 and 11-32 mya, respectively. Furthermore, deleting 10 adjacent taxa had a large effect in Pachysandra only, indicating that undersampling effects are significant among Buxales. Changes to sampling density in neighboring clades, or to the position of the fixed fossil calibration point had small to negligible effects. Non-parametric rate smoothing was more sensitive to taxon sampling effects than was penalized likelihood. The wide range for Podophyllum, compared to the other two genera, was probably due to a high degree of rate heterogeneity within this genus. Confidence ranges calculated by this method could be narrowed by sampling more individuals within the genus of interest, and by sequencing multiple DNA regions from all species in the phylogeny. 展开更多
关键词 basal eudicots fossil calibration molecular dating North America-East Asia disjunction taxon sampling Tertiary relict tricolpate pollen.
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Modern aspects of construction of information microwave therapy devices 被引量:1
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作者 Stanislav N. Darovskih Evgenij P. Popechitelev +1 位作者 Nadezhda V. Vdovina Ivan V. Novikov 《Natural Science》 2013年第12期1230-1237,共8页
This article is devoted to presenting modern aspects of building information microwave therapy devices. And it presents an analysis of the existing problems of the organism homeostasis control by means of electromagne... This article is devoted to presenting modern aspects of building information microwave therapy devices. And it presents an analysis of the existing problems of the organism homeostasis control by means of electromagnetic radiation. The new principles of synthesis of operating influences are formulated. On the basis of the thermodynamic approach is justified as a leading role modeling the space microwave background to restore disturbed homeostasis of the organism. The general patterns of development of the pathological process and possible mechanisms of corrective action of natural electromagnetic background are described. The implementation of the approach offered by the authors to constructing device information physiotherapy allowed creating high-performance hardware and software means for the prevention and treatment of a wide range of human diseases. 展开更多
关键词 INFORMATION Microwave Therapy HOMEOSTASIS ELECTROMAGNETIC POLLUTION relict RADIATION ELECTROMAGNETIC RADIATION
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Gravitational Energy Level and the Nature of Microwave Background of Universe 被引量:1
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作者 Vladimir Konushko 《Journal of Modern Physics》 2011年第4期175-187,共13页
In 1965, Penzias and Wilson discovered thermal radiation with T0 ~ 2.7 K further on called “relict”. This article is concerned with the new phenomenon, i.e. the formation of gravitational energy levels by any body, ... In 1965, Penzias and Wilson discovered thermal radiation with T0 ~ 2.7 K further on called “relict”. This article is concerned with the new phenomenon, i.e. the formation of gravitational energy levels by any body, with the result that photons are produced whose spectrum close to the Earth is similar to that of a blackbody with T0 ~ 2.7 K. The critical analysis of the experiments performed with the cosmic observatories COBE and WMAP completely confirms this prediction. 展开更多
关键词 MICROWAVE BACKGROUND relict
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Seasonal changes in the number of Relict Gull (Larus relictus) at Ebinur Lake, Western China
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作者 Kedeerhan BAYAHEN 《Journal of Arid Land》 SCIE 2010年第2期151-155,共5页
The Relict Gull(Larus relictus) is recognized as a vulnerable species,with a worldwide population of about 6,000 individuals.Always inhabiting the extreme arid regions of Central Asia,their migratory routes and winter... The Relict Gull(Larus relictus) is recognized as a vulnerable species,with a worldwide population of about 6,000 individuals.Always inhabiting the extreme arid regions of Central Asia,their migratory routes and winter grounds are unclear.This research focused on distribution sites,habitat,behavior,population size and seasonal changes of Relict Gull.Line transects and point counts in every month were used to investigate the gulls around the Ebinur Lake.The result showed Relict Gull was summer visitor to Xinjiang,Western China.Population curve with a single peak was obtained.This gull appeared in early April and was 63 individuals(1% of the global population).The number remained stable from May to July in 2009.The discovery of fledglings indi-cates that Relict Gull may breed here.They left Ebinur Lake in August.Relict Gull in Ebinur Lake should belong to the Central Asian subpopulation,which was the most westerly record in China. 展开更多
关键词 relict Gull(Larus relictus) POPULATION seasonal change Ebinur Lake Central Asia
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Deterioration of Early Holocene coral reef due to sea level rise along west coast of India:Benthic foraminiferal testimony
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作者 Abhijit Mazumder Rajiv Nigam Pravin J.Henriques 《Geoscience Frontiers》 SCIE CAS 2012年第5期697-705,共9页
A total of 103 surface sediment samples collected from the water depth range of 15-3300 m along Vijaydurg-Karwar stretch of central west coast of India were analyzed for foraminiferal content. Relict benthic foraminif... A total of 103 surface sediment samples collected from the water depth range of 15-3300 m along Vijaydurg-Karwar stretch of central west coast of India were analyzed for foraminiferal content. Relict benthic foraminiferal assemblage was noted within 50--135 m water depth. The relict benthic foraminiferal assemblage that includes Amphistegina, Operculina and Alveolinella in sediment samples within the water depth of 85-- 135 m indicates presence of coral reef at this depth during Early Holocene. The presence of barnacle fouling on Relict foraminifera at 60--90 m confirms the paleo-shoreline. The shallow depth zone is characterized by presence of agglutinated relict foraminifera. The agglutinated forms indicate freshwater influx, which eventually increased the sea level and subsequently deteriorated the paleo-coral reef. 展开更多
关键词 relict benthicforaminifera Early Holocene coral reefPaleo-shoreline West coast of India Sea level rise
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Holocene paleoenvironmental traces in soil profiles of Eastern Fennoscandia
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作者 Pavel Krasilnikov 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S1期91-96,共6页
After the deglaciation (ca. 12000 yr B.P.), climate of the Eastern Fennoscandianterritory varied. Changes in both temperature and moisture content lead to vegetative successionsand changes in soil formation. Though fo... After the deglaciation (ca. 12000 yr B.P.), climate of the Eastern Fennoscandianterritory varied. Changes in both temperature and moisture content lead to vegetative successionsand changes in soil formation. Though fossil soils are rare in Eastern Fennoscandia, numeroustraces of paleoenvironments are detected in soil profiles. We propose that in most cases climatic,water level, and vegetative changes were relatively rapid. A new soil profile started itsdevelopment, while the older one remained practically untouched. 展开更多
关键词 PODZOLS relict soils Holocen
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Identification,characteristics and classification of cryogenic block streams
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作者 Stuart A.Harris 《Research in Cold and Arid Regions》 CSCD 2016年第3期177-186,共10页
Cryogenic block streams consist of a stream of rocks superficially resembling a stream deposit but lacking a matrix, usually occurring on a valley or gully floor or on slopes that are less steep than the maximum angle... Cryogenic block streams consist of a stream of rocks superficially resembling a stream deposit but lacking a matrix, usually occurring on a valley or gully floor or on slopes that are less steep than the maximum angle of repose of coarse sediments. They are usually formed on perennially frozen ground, but can also occur as relict landforms. There are three main active kinds forming today, viz., Siberian and Tibetan dynamic rock streams and lag block streams. During their formation, the blocks in the active Siberian and Tibetan dynamic block streams move downslope at up to 1 rn/a. They are forming today on the Tibetan Plateau and in the more arid parts of south-central Siberia, although the processes involved in the movement are different. In the case of the Tibetan type, individual blocks slide downslope over the substrate in winter on an icy coating in areas of minimal winter precipitation. The Siberian type develops in areas of 15-80 cm of winter snow cover and an MAAT (mean annual air temperature) of-4 ~C to -17 ~C. The movement is due to creep of snow and ice and collapse of the blocks downslope during thawing. Lag block streams are formed by meltwater flowing over the surface of sediment consisting primarily of larger blocks with a limited amount of interstitial sediment. The erosion of the matrix is primarily in the spring in areas of higher winter precipitation on 10^-30~ slopes. The blocks remain stationary, but the interstitial sediment is washed out by strong seasonal flows of meltwater or rain to form an alluvial fan. The boulders undergo weathering and become more rounded in the process. Lag block streams can also develop without the presence of permafrost in areas with cold climates or glaciers. Block streams also occur as relict deposits in older deposits under various climatic regimes that are unsuitable for their formation today. An example of relict lag block streams with subangular to subrounded blocks occurs in gullies on the forested mountainsides at Felsen in Germany, and is the original 展开更多
关键词 active dynamic block streams felsemeer relict block steams Tibetan type block streams Siberian typeblock streams lag block streams
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Energy of the Gravitational Field as an Equivalent of the Dark Energy of the Universe
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作者 Valentyn Nastasenko 《Journal of Applied Mathematics and Physics》 2021年第7期1541-1548,共8页
Determination of the structural foundations and parameters of the Universe is an important urgent task since it enables us to understand and explain the structure and basic parameters of the material world. Herewith, ... Determination of the structural foundations and parameters of the Universe is an important urgent task since it enables us to understand and explain the structure and basic parameters of the material world. Herewith, it is necessary to be aware of modern problems of physics and possible ways to solve them. Among such problems, hypotheses concerning dark matter and the energy of the Universe occupy an important place. However, the determination of their on the basis of modern theories still leads to abstract equations that do not give concrete results;therefore, they have a level of hypotheses. A number of initial scientific propositions based on this abstract of mathematical dependencies have controversial meanings. Elimination of this disadvantage is the main goal of the work performed. Its main difference and scientific novelty are the justification of the energy parameters of the gravitational field of the Universe, the magnitude of which can replace its dark energy and dark mass. The solution to this problem is justified by strict physical dependencies, which are obtained on the basis of fundamental physical constants. It is an urgent and important scientific and applied problem, since it develops knowledge about the gravitational field and the material world in general. The performed work is based on the methods of deduction and induction in the research of the material world based on the application of the well-known reliable laws of physics and the general principles of the development of the theory of knowledge. Other research methods are still unknown, since the work performed is associated with new scientific discoveries, the search for which is difficult to formalize by technique methods. The results of the study consist of the analysis of wave, force and energy parameters of the relict gravitational field of the Universe. The calculated value of this energy is 1.58 × 10<sup>70</sup> J. This energy is enough to cover the amount of dark energy and mass in the Universe, which casts doubt on their existe 展开更多
关键词 Wave Force and Energy Parameters of the relict Gravitational Field of the Universe and the Possibility of Replacing of Them Dark Energy and Mass
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超大直径超深嵌岩旋挖分级成孔技术 被引量:2
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作者 许谷星 孙言 《山西建筑》 2022年第22期78-80,共3页
针对钻孔灌注桩工程中,超大直径,孔深超过50 m,且存在较厚中微风化残留体的情况下,选择正确的施工技术方案对工程实施具有十分重要的意义。结合深圳上沙某工程的实际,从施工设备选型、钻头(具)选择、施工方案确定提供了思路,并对旋挖分... 针对钻孔灌注桩工程中,超大直径,孔深超过50 m,且存在较厚中微风化残留体的情况下,选择正确的施工技术方案对工程实施具有十分重要的意义。结合深圳上沙某工程的实际,从施工设备选型、钻头(具)选择、施工方案确定提供了思路,并对旋挖分级成孔技术的关键点进行详细的介绍。 展开更多
关键词 超大直径 残留体 硬质岩 旋挖钻机
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有机演进遗迹类文化景观世界遗产的特征与启示——基于国际案例的分析 被引量:1
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作者 任伟 杨晨 《自然与文化遗产研究》 2021年第5期53-60,共8页
在文化景观类世界文化遗产理论和实践领域,由中国主导的国际世界遗产研究和实践有限。在自古以来“天人合一”“道法自然”的理念影响下,中国大地上竖立着众多实质上的文化景观,但是体现在书本上关于文化景观的研究较少,尤其是有机演进... 在文化景观类世界文化遗产理论和实践领域,由中国主导的国际世界遗产研究和实践有限。在自古以来“天人合一”“道法自然”的理念影响下,中国大地上竖立着众多实质上的文化景观,但是体现在书本上关于文化景观的研究较少,尤其是有机演进的景观的研究更少,专门针对有机演进遗迹类文化景观的研究目前几乎为空白。因此,文章立足分析国际上关于有机演进遗迹类文化景观的研究文献,对该领域中文较少的知识进行补充,并且对有机演进遗迹类文化景观的国际定义和发展脉络进行总结。根据教科文官方网站,文章选择了12个比较典型的国际有机演进遗迹类文化景观进行分析。分析遗迹被选为有机演进遗迹类文化景观的原因、突出普遍价值(OUV)与有机演进遗迹类文化景观的关系、完整性与有机演进遗迹类文化景观的关系、真实性与有机演进遗迹类文化景观的关系。文章首次从中国视角提出有机演进遗迹类文化景观认定的3个层级,希望能对中国有机演进遗迹类文化景观研究给予一定的启示。 展开更多
关键词 世界遗产 文化景观 有机演进 残迹 海龙屯
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comIntraspecific variation in heritable secondary metabolites and defensive strategies in a relict tree
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作者 Adara Pardo Yonatan Cáceres Fernando Pulido 《Journal of Plant Ecology》 SCIE CSCD 2018年第2期256-265,共10页
Aims Key herbivory interaction traits such as plant defensive compounds may differ among populations of a single species due to the spatial variation in herbivore feeding guilds and the strength of the interac-tion.Mo... Aims Key herbivory interaction traits such as plant defensive compounds may differ among populations of a single species due to the spatial variation in herbivore feeding guilds and the strength of the interac-tion.Moreover,the genealogy of population lineages could represent an additional source of variation interacting with the predominant eco-clinal trends.We tested for the existence of genetically based intraspecific variation in chemical defence profiles across the range of the relict tree Prunus lusitanica L.Additionally,we investigated geographical variation in defence inducibility and tested for the exist-ence of a trade-off between qualitative and quantitative defences.Methods We conducted a greenhouse experiment where 210 plants were grown under a common environment,comprising 10 different pop-ulations throughout the distribution range of the species and span-ning three separate regions:iberia,Morocco and Macaronesia.To test for the inducibility of defences,we artificially defoliated plants.Three treatments were established within each population:undam-aged,defoliated and sampled after 2 h,and defoliated and sampled after 72 h.The concentration of cyanogenic glycosides(prunasin)and phenolics was determined in leaf samples for all treatments.Important findings Basal levels of cyanogenics and phenolics significantly differed among populations and regions across the range of P.lusitanica,with this variation having a heritable basis.Cyanogenics(pruna-sin)were significantly higher in ancient Macaronesian populations,while phenolic concentrations were larger in iberia.The higher cyanogenic levels found in Macaronesia could be a consequence of the known stronger herbivory pressure in the islands than in iberia or the likely longer coevolutionary history with herbivores in this region.These findings indicate that the geographical variation of key ecological traits such plant chemical defences can be imprinted by phylogeographical signals,particularly in relict species.Regarding defence inducibility,prunasin inc 展开更多
关键词 HERBIVORY intraspecific variation PHYLOGEOGRAPHY plant defences relict flora
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首次发现具一枚苞片的珙桐花序(英文)
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作者 李晓东 李建强 +5 位作者 昝艳燕 王恒昌 雷孝平 田书荣 廖庆义 郭力宏 《怀化学院学报》 2007年第2期67-68,共2页
首次在贵州梵净山国家级自然保护区和湖南壶瓶山国家级自然保护区发现具一枚苞片的珙桐花序.珙桐是仅孑遗于我国的著名园林观赏树种,它花序苞片的多样性有助于我们对其遗传多样性和其进化的理解.
关键词 珙桐 一枚苞片 花序 孑遗
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