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在建隧道围岩变形自动信息化监控量测新技术
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作者 赵春华 张久林 《中文科技期刊数据库(全文版)工程技术》 2021年第11期136-138,共3页
以某在建高速公路隧道为例,隧道围岩形监控量测采用自动信息化监控量测系统,实现实时掌握围岩变形动态数据,为隧道围岩的熔岩形状变化预测、熔岩爆裂预测、围岩分类、二次支护分析和优化变更提供准确的数据支撑,也是隧道施工向信息化、... 以某在建高速公路隧道为例,隧道围岩形监控量测采用自动信息化监控量测系统,实现实时掌握围岩变形动态数据,为隧道围岩的熔岩形状变化预测、熔岩爆裂预测、围岩分类、二次支护分析和优化变更提供准确的数据支撑,也是隧道施工向信息化、智能化、大数据前进的一步。 展开更多
关键词 隧道围岩 发生形变 监控量测 自动信息化
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Age and Some Genetic Characteristics of Vertisols in China 被引量:2
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作者 ZHANGMIN LIULIANG-WU 《Pedosphere》 SCIE CAS CSCD 1993年第1期81-88,共8页
The ages of organic matter of some dark-colored horizons and calcareous concretions in some Vertisols from tropical, subtropical and warm-temperate zones of China were studied using radiocarb on dating method. The rel... The ages of organic matter of some dark-colored horizons and calcareous concretions in some Vertisols from tropical, subtropical and warm-temperate zones of China were studied using radiocarb on dating method. The relationship between soil age and genesis of Vertisols was also expounded based on the study of their genetic charactens-tics and micromorphological features. The results show that although Vertisols have developed for a relatively long time, their weathering and soil forming process are weak and young with little horizonation. This is closely related to their special geochemical soil forming environment. Low-lying terrain, heavy texture, clay minerals dominated by montmorillonites and alternative drying- wetting climate give rise to the vertic features expressed in intense swelling-shrinking and cracking-closing in soils. As a result, the soil development and soil leaching process are resisted, and the climatic effect on the horizonation is impeded. Moreover, pedoturbation eliminates the horizonation in the upper part of soil profile, and postpones their evolution into zonal soils. So Vertisols show certain pedogenic inertia and stay at relatively young developmental stage. Therefore, Vertisols are intrazonal soils dominated by local soil forming factors such as the relief and parent materials. 展开更多
关键词 soil age soil genesis soil micromorphology Vcrtisols
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Morphogenesis of Vertisols:A Model Study
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作者 QIURONG-LIANG HUANGRUI-CAI 《Pedosphere》 SCIE CAS CSCD 1994年第3期259-268,共10页
Studies on Vertisols of Southwest China show that the distribution of organic matter, mechanicalcomposition, carbonates and spore-pollen in their profiles exhibits a definite differentiation and the radiocarbon age ha... Studies on Vertisols of Southwest China show that the distribution of organic matter, mechanicalcomposition, carbonates and spore-pollen in their profiles exhibits a definite differentiation and the radiocarbon age has a functional variation with soil depth, which suggests that pedoturbation model is a kind of incomplete model for genetic study and that the disturbance and inversion of solums of Vertisol are not as rapid and absolute as expected. In further consideration of the characters of swelling pressure and shear strength of Vertisol, vertic soil and other zonal soils, it is speculated that soil mechanics model is more adaptable for interpreting the morphogenesis of Vertisols without any contradiction with soil properties. 展开更多
关键词 pedoturbation model soil mechanics model VERTISOLS
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Vascular plants distribution in relation to topography and environmental variables in alpine zone of Kedarnath Wild Life Sanctuary,West Himalaya
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作者 CHANDRA Sudeep SINGH Ankit +2 位作者 SINGH C.P. NAUTIYAL M.C. RAWAT L.S. 《Journal of Mountain Science》 SCIE CSCD 2018年第9期1936-1949,共14页
The present study was carried out in Tungnath alpine meadows of Kedarnath Wild Life Sanctuary, Western Himalaya from subalpine to upper alpine zone. A total of four summits were selected along an altitudinal gradient ... The present study was carried out in Tungnath alpine meadows of Kedarnath Wild Life Sanctuary, Western Himalaya from subalpine to upper alpine zone. A total of four summits were selected along an altitudinal gradient and sampled for detailed vegetation analysis using multi summit approach as per Global observation research initiative in alpine environments(GLORIA). Species richness, diversity, and evenness among four summits as well as the interaction between environmental variables with plant communities were assessed. Monthly mean soil temperature was calculated using data retrieved from geo-precision temperature logger in order to identify the trend of soil temperature among different season and altitudinal gradient and its implications to plant communities. Soil samples were analyzed fromeach summit by collecting randomized composite soil samples. The indirect non-metric multidimensional scaling(NMDS) and direct canonical correspondence analysis(CCA) tools of ordination techniques to determine the linkage between plant species from various sample summits and biotic/abiotic environmental gradients were used in the present study. The results of the study demonstrated increase in species richness as soil temperature increases, the ecotone representing summits were found most warm summits followed by highest species richness. Annual soil temperature increased by 1.43°C at timberline ecotone. Whereas, at upper alpine zone the soil temperature increased by 0.810 C from year 2015 to 2016. S?rensen's similarity index was found to be increased between subalpine and upper alpine zone with increase in the presence of subalpine plant species at upper alpine zone. Both the ordination tools separate the subalpine summit and their respective vegetation from summits representingtimberline ecotone and upper alpine zone. Soil p H, altitude, soil cation exchange capacity were found as the key abiotic drivers for distribution of plant species. 展开更多
关键词 GLORIA Non-metric multidimensionalscaling (NMDS) Canonical correspondence analysis(CCA) ECOTONE West Himalaya
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Morphogenic Variability of Some Autochthonous Plum Cultivars in the Region of North Montenegro
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作者 Gordana Sebek 《Journal of Agricultural Science and Technology(B)》 2013年第6期414-419,共6页
Plum is the major fruit species in the area of North Montenegro. Over a long period of growing in this region, autochthonous cultivars adapted, and have been achieving satisfactory results, despite poor growing condit... Plum is the major fruit species in the area of North Montenegro. Over a long period of growing in this region, autochthonous cultivars adapted, and have been achieving satisfactory results, despite poor growing conditions. A study conducted over a period of three years in a North Montenegro region included in situ identification of autochthonous plum cultivars. Observation and recording of their phenological and pomological traits were performed using International Board for Plant Genetic Resources (IBPGR) and International union for the Protection of New Varieties of plants (UPOV) methodologies. Eighteen cultivars derived from Prunusdomestica L. and two cultivars derived from P. insititia L. were identified. Flowering started between March 26th and April 12th and fruit ripening between 13th of July (Petrovaca) and 18th September (Trnovaca). Fruit weight ranged from 6.65 g ± 0.235 g to 53.88 g ± 0.654 g respectively and stone weight from 0.16 g ±0.003 g to 2.20 g ± 0.711 g. The cultivars were classified as being extremely small in terms of fruit size, except for cvs Crvenadurgulja (big fruit size). Rounded fruit shape and light green ground color were dominant. Skin color ranged from amber to black. Yellow green was a dominant flesh color and medium flesh firmness predominated. The fruits of the above cultivars could be processed, particularly into plum brandy, or they could be used fresh or dried. The selected plum cultivars can be used in breeding programmes, as rootstocks as well as in further disease related systematic studies under field and laboratory conditions. 展开更多
关键词 FRUIT genetic bases GERMPLASM Prunusdomestica L. Prunusinsititia L..
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The Study on Apparent Stress before and after the Minxian M_S6.6 Earthquake on July 22,2013
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作者 Chen Lijuan Li Yan'e +3 位作者 Yang Liming Chen Jifeng Chen Xuezhong Gong Liwen 《Earthquake Research in China》 CSCD 2016年第2期193-207,共15页
Based on the waveform data observed by the regional seismic network of Gansu Province,we calculated the apparent stress of 422 earthquakes with M_L≥ 2. 0 occurring in the surrounding area of the Minxian earthquake fr... Based on the waveform data observed by the regional seismic network of Gansu Province,we calculated the apparent stress of 422 earthquakes with M_L≥ 2. 0 occurring in the surrounding area of the Minxian earthquake from January 2010 to July 2014 and obtained the temporal and spatial variation of apparent stress before and after the Minxian earthquake. Results show that( 1) the high value of apparent stress of earthquakes with M_L≥4. 0 was concentrated in the epicenter area before the Minxian earthquake while that of earthquakes with M_L< 4. 0 was not;( 2) Apparent stress around the epicenter area showed an obvious increasing process before the Minxian earthquake and the increasing process has continued after the main shock,which means that this study area is still in the danger of strong earthquakes. 展开更多
关键词 The 2013 Minxian Ms6. 6 earthquake Apparent stress Temporal and spatialvariation
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Some thoughts on seismotectonics of major earthquake occurrence zones in China
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作者 Li Ping Huang Guangsi Yang Mei'e 《Engineering Sciences》 EI 2011年第4期2-10,共9页
A major earthquake occurrence zone means a place where M ≥6 events have occurred since the Holocene and similar shocks may happen again in the future. The dynamic context of the major earthquake occurrence zones in C... A major earthquake occurrence zone means a place where M ≥6 events have occurred since the Holocene and similar shocks may happen again in the future. The dynamic context of the major earthquake occurrence zones in China is primarily associated with the NNE-directed push of the India plate, next with the westward subduction of the Pacific plate. The Chinese mainland is a grand mosaic structure of many crust blocks bounded by faults and sutures. When it is suffered from boundary stresses, deformation takes place along these faults or sutures while the block interiors remain relatively stable or intact. Since the Quaternary, for example, left slip on the Xianshuihe-Xiaojiang fault zone in southwestern China has produced a number of fault-depression basins in extensional areas during periods Q1 and Q2. In the Q3, the change of stress orientation and enhancement of tectonic movement made faults of varied trends link each other, and continued to be active till present day, producing active fanlt zones in this region. Usually major earthquakes occur at some special locations on these active fault zones. During these events, in the epicenter areas experience intensive deformation character- ized by large-amplitude rise and fall of neighboring sections, generation of horst-graben systems and dammed rivers. The studies on palaeoearthquakes suggest that major shocks of close magnitudes often repeated for several times at a same place. By comparison of the Chi-Chi, Taiwan event in 1999 and Yuza, Yunnan event in 1955, including contours of accelerations and intensities, destruction of buildings, and in contrast to the Xigeda formation in southwestern China, a sandwich model is established to account for the mechanism of deformation caused by major earthquakes. This model consists of three layers, i.e. the two walls of a fault and the ruptured zone intercalated between them. This ruptured zone is just the loci where stress is built up and released, and serves as a channel for seismic waves. 展开更多
关键词 major earthquake occurrence zone mosaic structure active fault zone Chi-Chi Earthquake in Taiwan Yuza Earthquake in Yunnan
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Evolution of discocephalid ciliates:Molecular,morphological and ontogenetic data support a sister group of discocephalids and pseudoamphisiellids (Protozoa,Ciliophora) with establishment of a new suborder Pseudoamphisiellina subord.n. 被引量:2
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作者 MIAO Miao SHAO Chen +1 位作者 CHEN XuMiao SONG WeiBo 《Science China(Life Sciences)》 SCIE CAS 2011年第7期634-641,共8页
Discocephalids and pseudoamphisiellids are possibly two of the most confused groups among hypotrichous/euplotid ciliates regarding their systematic position and phylogenetic relationships.The former were often regarde... Discocephalids and pseudoamphisiellids are possibly two of the most confused groups among hypotrichous/euplotid ciliates regarding their systematic position and phylogenetic relationships.The former were often regarded as related to euplotids while the latter,in the absence of molecular data,were mostly assigned to the urostylid-like hypotrichs.In the present work,the small subunit rRNA genes of several rarely observed discocephalid and pseudoamphisiellid genera were analyzed to obtain insights into the phylogenetic relationships of these highly ambiguous Spirotrichea.Four different tree reconstruction algorithms yielded nearly identical topologies,which indicated both groups belong to the same assemblage.This assemblage is clearly isolated as a deep-branching clade and invariably positioned between Euplotida and Hypotricha.The sister group relationship of the Pseudoamphisiellidae and Discocephalidae supports the previous suggestion that they might represent an ordinal taxon,the Discocephalida.Both morphological and morphogenetic features indicate that the pseudoamphisiellids should be placed in the order Discocephalida but as a sister group to other typical discocephalids.Thus we propose establishing a new suborder,Pseudoamphisiellina subord.n.The new taxon is diagnosed by the following characteristics:(i) two distantly separated midventral rows that are morphogenetically formed with an urostylid mode;(ii) absence of the "frontoterminal row",which is formed from the posterior-most frontoventral-transverse cirral anlage in all other typical urostylids;(iii) numerous caudal cirri that derive from each of the dorsal kinety anlagen;(iv) right marginal row that has a unique de novo origin;and (v) inhabiting periphytic communities.The validity of the suborder Pseudoamphisiellina is firmly supported by molecular data. 展开更多
关键词 CILIOPHORA Discocephalida Pseudoamphisiellina subord n. new suborder phylogeny SSU rRNA gene
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Osteoinductivity assay of the variability of repeated extractions of bone morphogenetic proteins from bovine bone at different times 被引量:1
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作者 胡侦明 Sean AF Peel Cameron ML Clokie 《Chinese Journal of Traumatology》 CAS 2004年第5期301-307,共7页
Objective: To observe the activity of repeated extracts of bone matrix and the production of purified bone morphogenetic proteins (BMPs). Methods: BMPs were extracted 1- 4 times from fresh bovine cortical bone by the ... Objective: To observe the activity of repeated extracts of bone matrix and the production of purified bone morphogenetic proteins (BMPs). Methods: BMPs were extracted 1- 4 times from fresh bovine cortical bone by the modified Urist’s method, with each collected precipitate separated and lyophilized as partially purified BMPs. Another fresh bovine bone was extracted three times and the precipitates were mixed and lyophilized. Meanwhile,the alkaline phosphatase (ALP) activity was measured by an in vitro assay employing cultured C2C12 mouse myoblast cells through the osteoinductivity of bovine BMPs extracted four times at days 1, 4, 7, and 14, and the correlation between BMPs quantities and costing during extraction processes was analyzed.Results: The BMPs purified and the cost showed a positive correlation (r=(0.969)). To separate and lyophilize each collected precipitate as partially purified BMPs raised the cost, and mixed precipitates also cost much. ALP activities of the 1st and mixed extractions of BMPs were shown to be highly osteoinductive and keep a significantly high level (P<(0.05)-(0.01)) 4 days after culturing, compared with the 2nd, 3rd and 4th extractions, especially the control group. However, the more times the extraction was done, the less activity of BMPs was shown and more costing was. The x-ray and histological analysis also showed that the 1st extraction of BMPs induced more ossicles and new bone formation.Conclusions: The results indicated that BMPs enhanced the abilities of osteoinductivity in C2C12 culture in vitro. The first extraction of BMPs from bone is fitfull, the second extraction should be enough, while, the 3rd and 4th extractions are unnecessary for they cost more and waste more time, say nothing of mixed extractions. 展开更多
关键词 Bone morphogenetic proteins EXTRACTION
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