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Integrated hazard assessment of rockfall incidents in the Cap Aokas Cliff Region
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作者 Zohra LADJEL Farid ZAHRI +3 位作者 Riheb HADJI Younes HAMED Karim ZIGHMI Kaddour BENMARCE 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1916-1929,共14页
Rock fall accidents in mountainous cliff areas have significant consequences for human life and transportation.This study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast... Rock fall accidents in mountainous cliff areas have significant consequences for human life and transportation.This study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast coast of Algeria by identifying the key factors contributing to rockfall occurrence.We employed a combination of kinematic analysis,Matterocking method,and 3D trajectory simulations to determine zones that are susceptible to rockfall mobilization.By using a probabilistic and structural approach in conjunction with photogrammetry,we identified the controlling factors.The kinematic analysis revealed the presence of five discontinuity families,which indicated both plane and wedge failure modes.The 3D trajectory simulations demonstrated that the falling blocks followed the stream direction.We then validated the susceptibility maps generated from the analysis using aerial photos and historical rockfall events.The findings of this study enhance our understanding of rockfall phenomena and provide valuable insights for the development of effective strategies to mitigate rockfall hazards. 展开更多
关键词 Trajectory simulations Probabilistic analysis Structural approach Rockfall hazard Cap Aokas cliff
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Rayleigh-Bénard湍流热对流中主动和被动标量场Cliff结构统计特性的实验研究
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作者 周全 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第6期637-643,共7页
实验研究了Rayleigh-Bénard湍流热对流中主动和被动标量场Cliff结构的统计特性,实验参数Rayleigh数为Ra=1.2×1010,Prandtl数为Pr=5.3.在充满对流介质水的长方体对流槽边壁附近实验测量了局域浓度场(被动标量场)和局域温度场(... 实验研究了Rayleigh-Bénard湍流热对流中主动和被动标量场Cliff结构的统计特性,实验参数Rayleigh数为Ra=1.2×1010,Prandtl数为Pr=5.3.在充满对流介质水的长方体对流槽边壁附近实验测量了局域浓度场(被动标量场)和局域温度场(主动标量场)的时间序列,从测得的时间序列中提取出Cliff结构,提取参数为β,并分析了Cliff结构的宽度、振幅和尺寸的数量分布图.研究发现,浓度和温度场Cliff结构宽度的数量分布图形状并不随β而改变,而Cliff结构的最可几振幅却随着β的增大而增大.此外,Cliff结构的尺寸满足对数正态分布,这表明湍流热对流中被动标量场的扩散和混合是由羽流等浮力相干结构所驱动的. 展开更多
关键词 Rayleigh-Bénard 湍流热对流 标量湍流 主动标量 被动标量 Ramp-cliff结构
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The Cliff:A Deconstructive Analysis of The Catcher in the Rye
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作者 唐建南 《英语广场(学术研究)》 2012年第1期8-11,共4页
Just as the cliff serves as a demarcation between two different worlds, there seems to the protagonist in The Catcher in the Rye the dichotomies between innocence and corruption, children and adults. While these duali... Just as the cliff serves as a demarcation between two different worlds, there seems to the protagonist in The Catcher in the Rye the dichotomies between innocence and corruption, children and adults. While these dualisms are projected in the story, they are also deconstructed and the characterization of Holden clearly shows the instability of those dualisms. 展开更多
关键词 cliff DECONSTRUCTION DUALISM INNOCENCE CORRUPTION
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A model for calculating the erosion distance of soft sea cliff under wave loading 被引量:1
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作者 CHANG Fangqiang SHU Zhonglei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第7期69-77,共9页
A model for calculating the erosion distance of soft sea cliff under wave loading is established based on the erosion mechanism of soft sea cliff under wave loading and for considering wave hydrodynamic and sea cliff ... A model for calculating the erosion distance of soft sea cliff under wave loading is established based on the erosion mechanism of soft sea cliff under wave loading and for considering wave hydrodynamic and sea cliff material parameters.The model is verified,and the parameters are regressed using an indoor flume experiment.The erosion distances of the sea cliff in the northeast of the Pingtan Island are calculated by the model,and the results are compared with the measured data.The maximum erosion occurs in static water level,the location of the maximum erosion moves up as the wave continues,and the erosion stops when the wave lasts for a period of time.The erosion does not occur until the wave height exceeds a critical value; however,the contribution of large waves to the erosion is not relatively substantial.The calculated erosion distances at two places in the northeast of Pingtan Island are 0.32 m and 0.26 m. 展开更多
关键词 wave soft sea cliff EROSION
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A composite fall-slippage model for cliff recession in the sedimentary coastal cliffs 被引量:1
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作者 K.S.Sajinkumar J.P.Kannan +2 位作者 G.K.Indu C.Muraleedharan V.R.Rani 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第4期903-914,共12页
A composite fall-slippage model is proposed in this study for the Tertiary sedimentary coastal cliffs of Varkala in the western coastal tract of Peninsular India which are retreating landwards due to the combination o... A composite fall-slippage model is proposed in this study for the Tertiary sedimentary coastal cliffs of Varkala in the western coastal tract of Peninsular India which are retreating landwards due to the combination of several factors.The fall model in the present study accounts both spring seepage and wave action,resulting in undercutting and this fall affects only the topmost laterite and the just below sandstone in the cliff.Slippage in this area affects all the litho-units and hence the geologic characteristics of all the litho-units are considered for developing the slippage model.This mathematically derived model can be used in other cliffs exhibiting the same morphology as well as the one controlled by the same influencing factors.This model differs from other models in incorporating multi-lithounits as well as multi-notches.Varkala cliffs form a part of the aspiring geopark in the Global Geopark Network and hence a study on the cliff recession is a pressing requirement. 展开更多
关键词 Coastal cliff Coastal landslide cliff recession model Varkala
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分析电镜Cliff-Lorimer因子测量及薄标样标准化探讨
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作者 孙振亚 刘永康 《分析测试学报》 CAS CSCD 1999年第3期1-4,共4页
采用电子探针矿物标样,即均匀性和稳定性符合显微定量分析要求的国标样品,制备成适于分析电镜(AEM)成分分析的薄样品,测量了一组Clif-Lorimer(CL)因子,考察了用不同型号的分析电镜分析时CL因子的变化,提出... 采用电子探针矿物标样,即均匀性和稳定性符合显微定量分析要求的国标样品,制备成适于分析电镜(AEM)成分分析的薄样品,测量了一组Clif-Lorimer(CL)因子,考察了用不同型号的分析电镜分析时CL因子的变化,提出了仪器校正因子KI=εB/εA,对原子序数小于20的较轻元素其CL应考虑作KI校正;作者建议采用易于制成薄晶片的黑云母标样来统一不同分析条件下的CL因子,并应建立适于分析电镜定量分析的无机薄标样通用技术条件。 展开更多
关键词 K值 分析电镜 因子 薄标样 标准化 AEM CL因子
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The Environment Significance of Aerinite——First Discovered in the UBC Cliffs
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作者 WANG Guanyu WANG Hejing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期103-113,共11页
To analyze the composition and structure of the pale blue outcrop from the UBC Cliffs and research the environmental significance of aerinite recorded in the sediments, mineral composition, bulk chemical composition a... To analyze the composition and structure of the pale blue outcrop from the UBC Cliffs and research the environmental significance of aerinite recorded in the sediments, mineral composition, bulk chemical composition and structural analyses were carried out by means of X-ray diffraction(XRD), field emission scanning electron microscope(FESEM), transmission electron microscope(TEM), electron microprobe analysis(EMPA) and X-ray fluorescence spectra(XRF). Quartz, feldspar, mica, chlorite and aerinite as well as a small amount of amphibole, calcite, clinopyroxene, rutile, perovskite and apatite are recorded in the sediments. It is reported for the first time that the aerinite occurs in a high latitude area and in sediments paragenetic with mica and chlorite. The large span in grain size shows a typical characteristic of fluvioglacial sediments. Geochemistry characteristics(CIA, CIW, PIA, WIP and ICV) verify that there is virtually no chemical weathering. Mineralogy and geochemistry features of the UBC Cliffs sediments indicate that aerinite is accommodate to the high latitude and cold, dry climate. As the sediments show high similarity to those of their provenance, they have great significance in the identification of the forming condition and origin of the aerinite. 展开更多
关键词 UBC cliffS SEDIMENTS aerinite MUSCOVITE CHLORITE environment SIGNIFICANCE
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Cartography of Landslide Susceptibility around the Dias Horst and Thies Cliff-Senegal
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作者 Issa Ndoye Mapathé Ndiaye +2 位作者 Déthié Sarr Papa Sanou Faye Ibrahima Khalil Cissé 《International Journal of Geosciences》 2017年第6期821-836,共16页
The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and p... The aim of this work is to map the susceptibility of sites to landslides. To assess the susceptibility of the zone, GIS techniques were used. Susceptibility factors are selected and split into two groups: active and passive factors. Passive factors regroup all the intrinsic conditions existing on the field at all times. The active factors or triggering factors are present sporadically and are added to the passive factors to trigger a landslide. With the weighted overlay method using ArcGIS?, four scenarios have been developed. A first scenario where only passive factors are combined and three scenarios for which we have for each scenario the passive factors combined with an active factor. With these different scenarios, five levels of susceptibility are obtained in the zone. These levels range from very low to very high susceptibility. For the different scenarios, the results show that the zone consists mainly of very low to low susceptibility with at least 61% of the area, followed by moderate susceptibility (23.54% to 38.24%) and last land with high susceptibility to very high with less than 1% of the surface. Fields with high to very high susceptibility are located on the slopes of the hills. Among the active factors, only the rainfall significantly modifies the percentage of land susceptible to landslide but remains in the field of moderate susceptibility. The predicted susceptibilities are closer to the observed landslides around the Thies Cliff than to the Dias Horst. 展开更多
关键词 CARTOGRAPHY SUSCEPTIBILITY LANDSLIDES Dias HORST Thies cliff
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Connotations of architectural culture transmitted in cliff carvings in the Bashu region
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作者 林从华 《Journal of Chongqing University》 CAS 2006年第3期181-186,共6页
Based on site studies, historical literature investigation and academic communication, this work aims to dig out the cultural significance in architectural and religious aspects conveyed in cliff carvings in the Bashu... Based on site studies, historical literature investigation and academic communication, this work aims to dig out the cultural significance in architectural and religious aspects conveyed in cliff carvings in the Bashu region. After casting a glance at the origin and evolution of Bashu culture and religion mainly involving Daoism and Buddhism recorded in forms of cliff carvings, we concentrated on discovering the national, regional and folk architectural characters implicated in cliff carvings at different sites within the Bashu region. The cliff carvings in this region vividly depicted the evolution of the architectural culture hereof. The essence of their religious and architectural connotations can be good stuff to be input in today’s architectural design philosophy. 展开更多
关键词 cliff carvings architectural culture Bashu DAOISM BUDDHISM
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Succession of the Plant Communities of the Ustyurt Eastern Cliff (Republic of Uzbekistan) in Connection with Climate Change
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作者 Adilov Bekhzod Rakhimova Tashkhonim +2 位作者 Shomurodov Khabibullo Rakhimova Nodira Vokhidov Yusuf 《Journal of Environmental Protection》 2018年第13期1408-1424,共17页
A decrease in the amount of precipitation is observed on average 18 - 20 mm compared with the periods before the Aral crisis and the average annual temperature rise over the long-term period is 2.0°C in the Centr... A decrease in the amount of precipitation is observed on average 18 - 20 mm compared with the periods before the Aral crisis and the average annual temperature rise over the long-term period is 2.0°C in the Central part of Ustyurt. An increase in the Si index meaning an increase in the degree of drought every ten-flight is clearly expressed in the months March-July. Data Analysis 1981-2017 shows that within 36 years the species diversity in the monitoring sites of Kabanbay decreased by 2 - 3 times. In 1981 the number of species fluctuated between the values of 9 - 50, and in 2017 this figure is 4 - 17. The results of the analysis show that the forecast indicators of the old-current state (1981) of the vegetation coverage and number of species were stable or had tendencies with a low regressive character (r2 = 0.01). However, the current-state (2017) of the vegetation coverage and the species composition of the monitoring plots showed a low progressive trend (r2 = 0.03), i.e. in the future, the formation of plant communities with low vegetation coverage and species composition has a dominant status. The results show that in 1981, 65% - 80% of the species composition of plant communities consisted of halophyte and xerophyte groups. In 2017, this figure reaches 80% - 100%, i.e. this claims to increase xerophytization and halophytization of territories. An interesting fact is established with mesophyte group. In general, theoretically, the decrease in the number of mesophyte group of plants for 1981-2017 would have a direct correlation with the vegetation coverage and their active share in it. However, for 36 years, their active share in the vegetation coverage remained unchanged—amounting to 0% - 20%. Of course, in these years, the decrease in the number of mesophyte plants led to an increase in the number of plant communities, in which the proportion of vegetation coverage of mesophyte group is insignificant—0% - 5%. Despite the drought, the active part of the vegetation cover of mesophytic invasive species, such as Poa bulbosa, is consistently maintained. 展开更多
关键词 Ustyurt Plateau EASTERN cliff Climate Change SPECIES Diversity Total PROJECTIVE Cover Invasive SPECIES
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Geomechanical Characterization of Sandstones Cliffs of Segou (Senegal, West Africa) in the Madina Kouta Basin
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作者 Déthié Sarr Meissa Fall +3 位作者 Papa Malick Ngom Mapathé Ndiaye Cheikh H. Kane Makhaly Ba 《International Journal of Geosciences》 2012年第1期166-174,共9页
This work presents the behavior of Segou sandstones in the laboratory and in the field conditions. Four types of sandstone are collected in the northern part of the Madina Kouta basin (eastern Senegal). These types of... This work presents the behavior of Segou sandstones in the laboratory and in the field conditions. Four types of sandstone are collected in the northern part of the Madina Kouta basin (eastern Senegal). These types of specimens are the white sandstones, the red sandstones, the purple sandstones and the sandstones with intercalation of pelites. Uniaxial tests are carried out on these specimens of sandstones. The Young Moduli (E) and the Uniaxial Compression Strengths (Rc) are higher for the white sandstone. Values of the mechanical parameters decrease slightly for red sandstones due to an increase of the amount of pelites in the composition of the rock. Decrease of mechanical parameters is more important for the purple facies due to an important network of fractures. The facies with weaker characteristics corresponds to the sandstones with intercalation of pelites. This is due to the soft nature of the pelites. The slope stability of the Cliff sides depends also on to these characteristics. 展开更多
关键词 Unconfined Compression Test-Uniaxial Compression Strength (UCT Rc) JRC (Joint ROUGHNESS Coefficient) Young Modulus (E) ROUGHNESS Segou-Madina Kouta BASIN Discontinuities Dihedral Slope cliff
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山地城市崖壁景观特征及保护利用策略——以重庆两江四岸区域为例
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作者 李波 张钰姣 杜春兰 《风景园林》 北大核心 2024年第8期114-121,共8页
【目的】崖壁作为山地城市重要的地域性景观之一,在城市意象、社会生活和相关城市职能中发挥着重要作用。新时代背景下,崖壁景观的地位和角色也逐渐发生变化。崖壁景观的可持续发展于城市及其本身都具有重要意义,然而目前关于崖壁景观... 【目的】崖壁作为山地城市重要的地域性景观之一,在城市意象、社会生活和相关城市职能中发挥着重要作用。新时代背景下,崖壁景观的地位和角色也逐渐发生变化。崖壁景观的可持续发展于城市及其本身都具有重要意义,然而目前关于崖壁景观的系统性认知比较匮乏。【方法】以崖壁景观分布集中的重庆两江四岸区域为例,综合运用实地调查、史料梳理、ArcGIS空间分析等手段对山地城市崖壁景观特征及保护利用途径进行深入调查和讨论。【结果】两江四岸区域崖壁景观在总体空间分布上呈现依附山形地势与滨江临水两大特征;在空间形态上可划分为自然崖壁、人工介入崖壁,人工崖壁3种类型,自然崖壁生境类型丰富多样,人工介入崖壁和人工崖壁则相对单一;崖壁景观提供了多元复合的功能空间,是重要的人文景观载体。【结论】从崖壁空间功能转型、周边资源整合利用和自然生境保育3个方面提出崖壁景观的可持续发展策略,为山地城市崖壁景观的保护和开发利用提供参考。 展开更多
关键词 风景园林 崖壁景观 崖壁空间 崖壁生境 景观特征 山地城市 重庆两江四岸
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四川仁寿石佛湾摩崖造像调查简报
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作者 张亮 李瑞瑶 +5 位作者 胡盛 李杰 黄桥 李鑫 邓宏亚(摄影/绘图) 邓可人(绘图) 《敦煌研究》 北大核心 2024年第3期87-96,共10页
四川省仁寿县方家镇哨楼村石佛湾摩崖造像现存13龛,造像组合包括三佛、七佛、五十三佛、一弟子二胁侍、一佛二菩萨、一佛二弟子二菩萨等,可辨题材有弥勒、僧伽、三世佛、过去七佛、五十三佛、一佛五十二菩萨等瑞像。根据造像题材及风格... 四川省仁寿县方家镇哨楼村石佛湾摩崖造像现存13龛,造像组合包括三佛、七佛、五十三佛、一弟子二胁侍、一佛二菩萨、一佛二弟子二菩萨等,可辨题材有弥勒、僧伽、三世佛、过去七佛、五十三佛、一佛五十二菩萨等瑞像。根据造像题材及风格,可推断石佛湾摩崖造像开凿于8世纪晚期至9世纪上半叶。 展开更多
关键词 仁寿县 石佛湾 摩崖造像 中晚唐
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重庆崖线型绿道夏季热环境及影响要素研究——以佛图关公园为例
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作者 杨真静 杨党燊 何媛 《建筑技艺(中英文)》 2024年第1期84-88,共5页
崖线型绿道是依托重庆特有的山崖线型空间修建的绿道,通过改善夏季热环境,对健康出行有重要意义。通过对佛图关公园内的绿道进行测试,探究其热环境现状与影响机理。发现不同空间形式的绿道热环境差异显著,日照时长和地表均温与UTCI1呈... 崖线型绿道是依托重庆特有的山崖线型空间修建的绿道,通过改善夏季热环境,对健康出行有重要意义。通过对佛图关公园内的绿道进行测试,探究其热环境现状与影响机理。发现不同空间形式的绿道热环境差异显著,日照时长和地表均温与UTCI1呈强正相关,在提高绿道热环境方面,绿化山体优于树木,绿地优于石材铺装的下垫面。 展开更多
关键词 崖线型绿道 室外热环境 UTCI
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大兴安岭古代多文种摩崖题记铭文
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作者 青格力 《中国蒙古学(蒙文)》 2024年第3期134-152,215,共20页
作者及考察组自2019年以来以大兴安岭地区为重点,开展广泛的古代多文种摩崖题记铭文调查研究,在赤峰市、兴安盟、通辽市、呼伦贝尔市、锡林郭勒盟等游牧山区以及呼和浩特等古代通道相关地点进行历史遗迹踏查,发现60多处600余条辽、金、... 作者及考察组自2019年以来以大兴安岭地区为重点,开展广泛的古代多文种摩崖题记铭文调查研究,在赤峰市、兴安盟、通辽市、呼伦贝尔市、锡林郭勒盟等游牧山区以及呼和浩特等古代通道相关地点进行历史遗迹踏查,发现60多处600余条辽、金、元、明、清时期形成的题记碑刻铭文,涉及汉文、契丹大字、契丹小字、女真文、回鹃文、回鹃蒙古文、八思巴文、叙利亚文、梵文、波斯文、藏文等多文种。这些摩崖题记铭文多数为墨书题记,国内属于首次发现,文种多样并且规模惊人,是极为珍贵的中国古代北方地区多文种历史文化文献史料群。 展开更多
关键词 大兴安岭 多文种 摩崖题记 古文字
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四川资阳中和镇菩萨岩、临江镇佛尔岩摩崖造像调查简报 被引量:1
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作者 童瑞雪 王屹 +3 位作者 白彬 赵赫(绘图) 寇小石(绘图) 谈北平(摄影) 《敦煌研究》 北大核心 2024年第2期85-97,共13页
资阳市中和镇菩萨岩与临江镇佛尔岩摩崖造像均为沱江流域中晚唐时期的典型造像点,二者在龛形、题材和造像风格等方面皆有相似之处。前者雕刻较精美但纪年缺失,后者虽被盗损却有明确纪年题记,可互为参照。综合崖面布局、纪年题记以及其... 资阳市中和镇菩萨岩与临江镇佛尔岩摩崖造像均为沱江流域中晚唐时期的典型造像点,二者在龛形、题材和造像风格等方面皆有相似之处。前者雕刻较精美但纪年缺失,后者虽被盗损却有明确纪年题记,可互为参照。综合崖面布局、纪年题记以及其他参考因素,初步判断两处造像集中开凿于8世纪下半叶到9世纪初期,晚唐及以后有补凿、搭建建筑和妆彩活动。两处造像题材有一佛、三佛与多身胁侍(含天龙八部)的组像、五十三佛、舍利塔等。 展开更多
关键词 资阳 摩崖造像 中晚唐 沱江流域
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山西沁源枣林庄、柳湾摩崖造像调查简报
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作者 武夏(摄影) 徐晴(绘图) +4 位作者 姬凌飞(绘图) 刘亚楠(绘图) 马楠 李辉 冯鹏锦 《考古与文物》 北大核心 2024年第8期38-50,共13页
2021年1月和4月,山西大学考古系对山西长治沁源枣林庄、柳湾摩崖造像进行了两次调查。枣林庄摩崖造像开凿有3个主龛,龛下刻有供养人形象及题记,据造像题材与风格推断应开凿于北魏晚期。柳湾摩崖造像共有12龛,风化较为严重,根据造像题材... 2021年1月和4月,山西大学考古系对山西长治沁源枣林庄、柳湾摩崖造像进行了两次调查。枣林庄摩崖造像开凿有3个主龛,龛下刻有供养人形象及题记,据造像题材与风格推断应开凿于北魏晚期。柳湾摩崖造像共有12龛,风化较为严重,根据造像题材与风格推断应陆续开凿于东魏北齐时期。此次调查为研究晋东南地区北朝佛教遗存的年代序列以及佛教的传播路线等提供了重要资料。 展开更多
关键词 山西 枣林庄 柳湾 摩崖造像 北朝
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海南岛峨蔓五彩湾内海蚀平台对海蚀崖侵蚀的影响研究
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作者 赵中伟 吴凌云 +1 位作者 高伟健 李伟 《热带海洋学报》 CAS CSCD 北大核心 2024年第5期106-115,共10页
全球海洋变化所引起的极端波浪海洋灾害趋强,势必会加剧海南岛的海蚀崖侵蚀地质灾害危险。海蚀平台能够有效衰减波浪能量,从而降低极端波浪对海蚀崖的侵蚀破坏。海南岛西北部的火山岩基岩海岸地区,存在大量海蚀平台地貌,是研究海蚀平台... 全球海洋变化所引起的极端波浪海洋灾害趋强,势必会加剧海南岛的海蚀崖侵蚀地质灾害危险。海蚀平台能够有效衰减波浪能量,从而降低极端波浪对海蚀崖的侵蚀破坏。海南岛西北部的火山岩基岩海岸地区,存在大量海蚀平台地貌,是研究海蚀平台对海蚀崖侵蚀影响的理想地区。文章以海南岛儋州市峨蔓镇的五彩湾基岩海岸为研究对象,利用海洋遥感影像刻画了五彩湾海蚀崖近十年的平均侵蚀速率达0.26m·a^(−1),通过物理海洋分析方法预测了研究区未来100年回归周期可能遭受的最大波高达7.8m,进一步基于海岸地貌研究方法调查了五彩湾倾斜型海蚀平台的地貌特征,及其后部海蚀崖岩石的抗侵蚀强度,从而通过数值计算证明了海蚀平台可以使得未来极端波浪对五彩湾海蚀崖的侵蚀强度平均减缓80%以上。此外,文章进一步探讨了五彩湾海蚀崖底部沉积沙滩、崖底植被和海蚀崖滑塌堆积物的天然护岸作用。 展开更多
关键词 海蚀平台 海蚀崖侵蚀 玄武岩海岸 数值计算 海南岛
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江苏省南通市居民二胎或三胎意愿调查及影响因素分析
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作者 薛云薇 朱昱 +5 位作者 潘利娟 苏青 杨佳琪 陈铭 张玉泉 苏敏 《当代医学》 2024年第9期83-88,共6页
目的探讨生育率断崖式下降形势下的江苏省南通市居民二胎或三胎意愿及影响因素。方法采取简单随机抽样法选取2021年11月至2022年1月于江苏省南通市居住的居民作为调查对象,采用网络问卷调查的方法,调查其个人情况、家庭情况、生育二胎... 目的探讨生育率断崖式下降形势下的江苏省南通市居民二胎或三胎意愿及影响因素。方法采取简单随机抽样法选取2021年11月至2022年1月于江苏省南通市居住的居民作为调查对象,采用网络问卷调查的方法,调查其个人情况、家庭情况、生育二胎或三胎的意愿,分析影响二胎或三胎生育意愿的因素。共发放1090份问卷,有效回收1086份问卷,问卷有效回收率为99.63%,问卷的信度系数为0.732,效度系数0.792。结果1086名居民中,有生育二胎意愿或已经生育二胎的占比32.87%,无意愿生育二胎的占比67.13%;不同年龄、婚姻状况、学历、职业、生育情况、理想的孩子个数、理想的头胎生育年龄、生育后幸福程度、本人兄弟姐妹个数、头胎生育年龄对于二胎的生育意愿比较差异有统计学意义(P<0.05)。1086名居民中,有生育三胎的意愿或已经生育三胎的占比2.95%,无意愿的占比97.05%;不同性别、年龄、学历、职业、生育情况、理想的孩子个数、理想的头胎生育年龄、家庭收入、生育后幸福程度、对于三胎的生育意愿比较差异有统计学差异(P<0.05)。居民不愿意生育二胎的原因主要是:缺乏时间、精力(83.13%),育儿成本高(71.88%),经济压力大(65.16%),居民愿意和不愿意生育三胎的原因与二胎相似。经济状况、身体状况、工作状况是影响居民再生育意愿的重要因素。结论南通市居民二胎生育意愿不强,生育三胎意愿极低,时间和精力、经济压力、社会保障体系是影响居民生育二胎、三胎的重要因素。 展开更多
关键词 生育率断崖式下降 二胎/三胎生育意愿 影响因素
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宝资山汉代崖墓出土陶楼粘接材料的科学分析
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作者 葛若晨 孙杰 +5 位作者 陈翩 付金凤 曾帆 刘志 杨波 杨璐 《文物保护与考古科学》 北大核心 2024年第4期32-39,共8页
陶器上的古代粘接材料与陶器的修复工艺关系密切,是当时社会制陶水平的反映之一。本研究对成都新津宝资山汉代崖墓出土陶楼上的粘接材料进行了科技分析,使用了扫描电子显微镜-能谱仪(SEM-EDS)、X射线衍射仪(XRD)、激光粒度分析仪、傅里... 陶器上的古代粘接材料与陶器的修复工艺关系密切,是当时社会制陶水平的反映之一。本研究对成都新津宝资山汉代崖墓出土陶楼上的粘接材料进行了科技分析,使用了扫描电子显微镜-能谱仪(SEM-EDS)、X射线衍射仪(XRD)、激光粒度分析仪、傅里叶变换红外光谱仪(FTIR)和气相色谱-质谱联用仪(GC-MS),分别探究了该粘接材料中的无机和有机成分。结果表明:粘接材料的颗粒状态、大小和成分与黏土颗粒相似,推断其主要无机成分为黏土;红外吸收光谱在波数3431 cm^(-1)、1670 cm^(-1)和1419 cm^(-1)的特征峰与酰胺基相吻合,氨基酸分析表明其有机成分含有由动物胶和蛋类混合而成的蛋白质类胶料。有机混合胶料黏性较高,弥补了单一胶料使用的不足,同时黏土可增加系统中的氢键密度,并起填充作用,这样的协同作用是该粘接材料在使用时具有强粘接力和一定稳定性的原因。但由于其耐久性差且与陶器整体风格不协调,推测该材料是在器物下葬前使用的一种临时粘接剂。同时,它的成分和用途与秦始皇陵兵马俑上的古粘接材料非常相似,这体现了汉代对秦代帝陵陪葬制度和制陶工艺的继承与沿革。研究结果为我国陶器修复历史的研究提供了资料,同时也为现代陶器的保护修复提供了科学依据。 展开更多
关键词 宝资山汉代崖墓 彩绘陶楼 粘接剂 “有机-无机”复合材料 汉承秦制 陶器修复
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