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瑞信·今日艺术奖——黄然
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《东方艺术》 2011年第19期144-145,共2页
黄然,1982年生于四川西昌,目前在北京和伦敦工作。2004年他以年级第一的成绩毕业于英国伯明翰艺术与设计学院,并获得纯艺术一等荣誉学士学位。2007年,毕业于英国伦敦Goldsmiths College(英国)纯艺术硕士专业。2009年。黄然成为由... 黄然,1982年生于四川西昌,目前在北京和伦敦工作。2004年他以年级第一的成绩毕业于英国伯明翰艺术与设计学院,并获得纯艺术一等荣誉学士学位。2007年,毕业于英国伦敦Goldsmiths College(英国)纯艺术硕士专业。2009年。黄然成为由欧洲媒体艺术家进驻计划(EMARE)、欧盟文化部、以及英国艺术委员会共同支持的16位艺术家之一,在英国和德国完成了艺术家进驻项目。 展开更多
关键词 黄然 2007年 2009年 艺术家 设计学院 学士学位 硕士专业 欧洲媒体
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黄然:形体越渡之可能
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作者 杨北辰 多多 《艺术界》 2012年第3期144-151,16,共8页
从概念的探讨到造型的试验,黄然对形体"越渡"之可能性的探索,正走到一个未知与不可测的节点。
关键词 黄然 艺术家 艺术创作 艺术作品
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Acid mine drainage activation mechanism on lime-depressed pyrite flotation from copper sulfide ore
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作者 Jia-qiao YUAN Zhan DING +3 位作者 Yun-xiao BI Jie LI Shu-ming WEN Shao-jun BAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2987-3001,共15页
The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of l... The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of laboratory flotation tests and surface analytical techniques.Flotation test results indicated that AMD could effectively activate the pyrite flotation with a sodium butyl xanthate(SBX)collector,and a high-quality sulfur concentrate was obtained.Pulp ion concentration analysis results indicated that AMD facilitated desorption of Ca^(2+)and adsorption of Cu^(2+)on the depressed-pyrite surface.Adsorption measurements and contact angle analysis results confirmed that adding AMD improved the adsorption amount of SBX collector on the pyrite surface and increased the contact angle by 31°.Results of Raman spectroscopy and X-ray photoelectron spectroscopy analysis indicated that AMD treatment promoted the formation of hydrophobic species(S^(0) hydrophobic entity and copper sulfides)and the removal of hydrophilic calcium and iron species on the pyrite surface,which reinforced the adsorption of collector.The findings of the present research provide important theoretical basis and technical support for a cleaner production of copper sulfide ores. 展开更多
关键词 copper sulfur ore acid mine drainage lime-depressed pyrite FLOTATION natural activator activation mechanism
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Multi-scale Distribution Pattern of Natural Ramet Population in the Rhizomatous Herb ,Thermopsis lanceolata 被引量:11
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作者 于飞海 董鸣 《Acta Botanica Sinica》 CSCD 1999年第12期1332-1338,共7页
Thedistributionpatternofnaturalrametpopulationintherhizomatousherb ,Thermopsislanceolata R .Br.,at 5scales (0 .2m ,0 .4m ,0 .6m ,0 .8mand 1.0m)wasinvestigatedusinggridsamplingand spatialauto_correlationanalysis (Mo... Thedistributionpatternofnaturalrametpopulationintherhizomatousherb ,Thermopsislanceolata R .Br.,at 5scales (0 .2m ,0 .4m ,0 .6m ,0 .8mand 1.0m)wasinvestigatedusinggridsamplingand spatialauto_correlationanalysis (Moran’sI)inMaowususandlandofInnerMongoliaofChina .Theresult showedthattherametpopulationhadnon_randomdistributionpatternatfourscales (0 .2m ,0 .4m ,0 .6m and 1.0m) .Themostfrequentlyobservedpatternwascontagiousatthescaleof 0 .2m .Thegenethadsym podialgrowthandnearlyphalanxarchitecture .Thebranchingangleoftherhizomeswasfrom 10°to 30° .The densityoftherametpopulationwasfrom 35to 131ramets·m- 2 .Themeanheightoframetswasbetween 11.0 cmand 2 5.9cm .Thebiomassoftherametpopulationwas 2 6 3.6 3g·m- 2 and 30 6 .19g·m- 2 inthetwo plots,respectively .33.71%and 4 4 .97%ofthebiomassallocationtorhizomeswereobservedandthe biomassallocationtorootswas 2 9.91%and 2 9.95%andthattoleaveswas 2 5.12 %and 36 .35%inthetwo plots ,respectively .Theratioofroottoshootwas 0 .4 4inbothplotswhiletheratioofbelow_toabove_ground biomasswas 2 .12and 3.59,respectively . 展开更多
关键词 Clonalplant Clonalarchitecture Multi_scalepattern Spatialauto_correlationanalysis Ther mopsislanceolata
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Plant Traits and Soil Chemical Variables During a Secondary Vegetation Succession in Abandoned Fields on the Loess Plateau 被引量:80
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作者 王国宏 《Acta Botanica Sinica》 CSCD 2002年第8期990-998,共9页
Species dynamics in terms of both plant biological traits, ecological strategies and species richness as well as soil chemical variables during a secondary succession in abandoned fields on the Loess Plateau along a t... Species dynamics in terms of both plant biological traits, ecological strategies and species richness as well as soil chemical variables during a secondary succession in abandoned fields on the Loess Plateau along a temporal sere from 3 a to 149 a were studied. The results indicated that (I) Soil total C and N increased while soil pH, total K and Na decreased with years since abandonment. No noticeable trend was found in the case of soil P along the successional sere. On the other hand, total CaO of the surface layer (0 - 10 cm) decreased, but that of the two deeper layer, (20 - 30 cm, 40 - 50 cm) increased with years since abandonment. Soil C, N, K and P decreased, while Na, CaO and soil pH increased with increasing soil depth. (2) Species richness peaked at both mid-stage of the successional sere and the intermediate portion of soil chemical variables gradient. (3) An ideal dominant species in the early successional stage were annuals with stable seed pool, CR-life strategy, S-regeneration strategy, and strong competitive ability on relatively poor soil, while perennials capable of intensive lateral spread and colonal ability, requiring high nutrient supply, and having Clife strategy would be the dominant species in the subsequent stages. Plant traits, such as perennial-life history, C-, CR-, SC-, SR-, S- and R-life strategies, W-, S-, Bs- VBs- and V-regeneration strategies, were over- represented throughout the whole sere among the other species. (4) Some traits, such as C-, SC-life strategies, ability of clonality, perennial-life history, well-developed lateral spread ability, V- and VBs-regeneration strategies, seed animal. dispersal mode, flowering time of autumn, fruit types of legumen and nut, were more or less correlated with increased soil total C, N and K, while S-, SR-, R-, CR-life strategies, annual-, biannual-life history, non-clonal ability, S-regeneration strategy, poor lateral spread ability, and fruit types of utricle, capsule were associated with increased soil total Na, CaO and pH. The results suggested that steppes should be the dominant native vegetation coinciding with the large-scaled eco-climatic conditions on the Loess Plateau. 展开更多
关键词 abandoned fields plant trait soil chemical variable SUCCESSION Loess Plateau
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Landslide disaster in the loess area of China 被引量:17
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作者 周金星 朱春云 +2 位作者 郑景明 王晓慧 刘洲鸿 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期157-161,165,共5页
China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and bec... China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and becomes major factors hindering the social and economic development of loess regions. Through different indexes, the authors divided the landslides into 9 principal types and analyzed the distribution characteristics of loess landslide in time and space, the affecting factors and mechanism of landslides. It is pointed out that time and spatial distributions of landslides are closely correlative to topographic and geomorphic conditions, earthquake and rainfall, and the key influencing factors include topography, geomorphology, new tectonic movements, earthquake activity, surface water, ground water and human activities. The authors emphasized that the natural condition of loess areas was favorable to landslides, human activities impelled its occurrence and that controlling the loess landslide was an urgent task for sustainable development in the loess zone. 展开更多
关键词 Loess landslide Landslide mechanism Natural disasters
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Breeding of a Natural Colored-Cocoon Bombyx mori Variety Shuhuang No.1
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作者 刘俊凤 刘彬斌 +1 位作者 陈义安 肖金树 《Agricultural Science & Technology》 CAS 2013年第8期1183-1187,1194,共6页
[Objective] This study aimed to develop a new Bombyx mori variety Shuhuang No.1 and investigate its characteristics.[Method] The new variety was developed through cross breeding and pedigree separation.Its characteris... [Objective] This study aimed to develop a new Bombyx mori variety Shuhuang No.1 and investigate its characteristics.[Method] The new variety was developed through cross breeding and pedigree separation.Its characteristics were identified by laboratory tests and rural promotion practices in Sichuan Province.[Result]The cocoon produced by the new variety Shuhuang No.1 was golden-yellow and radiantly beautiful.Shuhuang No.1 was strong and easy to rear,uniform in development.The male and female ones could be distinguished by their larval color and markings.The cocoon yield per 10 000 the 4th instar larvae reached 20.30 kg; the length of a cocoon filament was about 1 115.0 m,and a non-broken filament was 882.95 mm long,accounting for 79.15% of the total length.The raw silk ratio of fresh cocoon was 18.39%,and the neatness was 91.25 point.The main economic features of Shuhuang No.1 were better than those of the control.[Conclusion] The new variety had been approved by Sichuan Silkworm Evaluation Commission.It can be promoted in parent silkworm rearing areas Sichuan,Chongqing,Yangtze River basin. 展开更多
关键词 Natural colored cocoon Bombyx mori Shuhuang No.l CROSSBREEDING Pedigree selection
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Aggregate Characteristics During Natural Revegetation on the Loess Plateau 被引量:13
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作者 AN Shao-Shan HUANG Yi-Mei +1 位作者 ZHENG Fen-Li YANG Jian-Guo 《Pedosphere》 SCIE CAS CSCD 2008年第6期809-816,共8页
Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The... Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The relationship between water- stable aggregates and other soil properties was analyzed using canonical correlation analysis and principal component analysis. The results show that during the natural revegetation, the aggregates 〉 5 mm dominated and constituted between 50% and 80% of the total soil water-stable aggregates in most of the soil layers. The 2-5 mm aggregate class was the second main component. The mean value of water-stable aggregates 〉 5 mm within the 0-2 m soil profile under different plant communities decreased in the following order: Stipa grandis 〉 Stipa bungeana Trin. 〉 Artemisia sacrorum Ledeb. 〉 Thymus mongolicus Ronn. 〉 Hierochloe odorata (L.) Beauv. Clay, organic matter, and total N were the key factors that influenced the water stability of the aggregates. Total N and organic matter were the main factors that affected the water stability of the aggregates 〉 5 mm and 0.5-1 mm in size. The contents of Fe2O3, Al2O3, and physical clay (〈 0.01 mm) were the main factors which affected the water stability of the 1-2 and 0.25-0.5 mm aggregates. 展开更多
关键词 canonical correlation analysis loess area natural revegetation principal component analysis soil water- stable aggregates
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Mechanical activation of natural chalcopyrite for improving heterogeneous Fenton degradation of tetracycline 被引量:2
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作者 WANG Chong-qing YANG Jia-peng +1 位作者 HUANG Rong CAO Yi-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第12期3884-3895,共12页
Natural minerals receive growing attention as inexpensive, green, and efficient catalysts for degradation of organic pollutants. Mechanical activation of natural chalcopyrite was conducted for improving the catalytic ... Natural minerals receive growing attention as inexpensive, green, and efficient catalysts for degradation of organic pollutants. Mechanical activation of natural chalcopyrite was conducted for improving the catalytic performance.Tetracycline degradation was evaluated in the presence of hydrogen peroxide and mechanically activated chalcopyrite.Tetracycline degradation at 100 min is 55.52%(Chp10), 68.97%(Chp30), 77.79%(Chp60), and 86.43%(Chp120),respectively, and the rate constant of pseudo-first-order kinetics is 0.0079, 0.0109, 0.0137 and 0.0192 min^(-1), respectively.Chalcopyrite samples were examined by multiple characterizations. Mechanical activation of natural chalcopyrite induces the decline of particle size and slight increase of surface area, smaller grain size, lattice strain, and partial sulfur oxidation. The relationship between catalytic activity and property change manifests that the improved catalytic ability is mainly ascribed to the increase of surface area and surface oxidation induced by mechanical activation. This work provides novel insights into the improvement of catalytic performance of natural minerals by mechanical activation. 展开更多
关键词 advanced oxidation process CHALCOPYRITE mechanical activation natural minerals TETRACYCLINE
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Effects of Dried Black Cumin and Tamarind Supplementation on Egg Performance and Lipids Concentration in Egg Yolk of Layer Hens
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作者 S. Yingyuen S. Wongsuthavas +4 位作者 C. Yuangklang K. Vasupen S. Bureenok S. Kempaka A. C. Beynen 《Journal of Agricultural Science and Technology(A)》 2011年第8期1133-1136,共4页
This study was aimed to determine the effects of dried black cumin and tamarind supplementation on egg performance and lipids concentration in egg yolk of layer hens. Sixty laying hens at the age of 18-34 weeks were d... This study was aimed to determine the effects of dried black cumin and tamarind supplementation on egg performance and lipids concentration in egg yolk of layer hens. Sixty laying hens at the age of 18-34 weeks were divided into 4 treatments (control, 1% black cumin, 4% tamarind and 1% black cumin + 4% tamarin in diets) with 4 replications each (15 birds/replication). The experimental treatments were subjected to completely randomized design. Feed and drinking water were provided ad-libitum. 16 h per day for lighting program during experimental period. The results found that feed efficiency ratio, egg production and egg weight were no significant between treatments. However, average daily feed intake was highest in 4% tamarind and 1% black cumin + 4% tamarin in diets. Egg yolk color score, yolk index, white index and shell tickness were no significantly different, However, haugh unit was lowest in control group. Egg yolk lipids concentration was founded that black cumin and tamarind in diet were reduced cholesterol and triacyl-glycerol concentration with statistical significance (P 〈 0.05). So that dried black cumin and tamarind supplementation in diets were no any effect on egg production and egg weight. Furthermore, egg yolk cholesterol and triacyl-glycerol concentration were decreased. Hence, supplementation of dried black cumin and tamarind in diets could benefit to consumer health. 展开更多
关键词 Black cumin TAMARIN laying hen cholesterol TRIGLYCERIDE
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Nitrogen Forms in Humic Substances
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作者 ZHUOSU-NENG WENQI-XIAO 《Pedosphere》 SCIE CAS CSCD 1992年第4期307-315,共9页
In this paper,the nitrogen forms in newly-formed humic substances,including humic acid (HA),fulvic acid (FA) and humic acid in humin (HAI),were studied by using the ^15N CP-MAS NMR technique in combination with chemic... In this paper,the nitrogen forms in newly-formed humic substances,including humic acid (HA),fulvic acid (FA) and humic acid in humin (HAI),were studied by using the ^15N CP-MAS NMR technique in combination with chemical approaches.Results show that the majority of nitrogen in HA,FA and HAI was in the amide form with some presented as aliphatic and/ or aromatic amines and some as pyrrole type nitrogen,although the contents of nonhydrolyzable nitrogen in them differed greatly from each other (15-55%). 展开更多
关键词 fulvic acid humic acid 15N CP-M AS NMR nitrogen forms
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The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain
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作者 马建华 李剑 千怀遂 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期437-446,共10页
The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern ... The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern plain and the other is from southern subtropical zone to northern temperate zone. Torrential rain, especially strong torrential rain is frequent in the transitional region, and there are many torrential rain centers. A majority of torrential rain is distributed among 100-200 m asl. The winter temperature at 100-400 m asl is higher than that in Huanghuai Plain whose altitude is lower than that of the transitional region, and the highest temperature in January appears at 350-400 m asl.The thickness of warm slope belt in the transitional region varies from 100 m to 250 m asl. The formation of torrential rain and warm slope belt is the result of joint action of atmospheric circulation and local terrain. Frequent torrential rains and warm slope belt had tremendous influences on the soil properties, plant distribution and local climate in the transitional region. 展开更多
关键词 qinling mountains huanghuai plain characters of physical geography torrential rain warm slope belt
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The Effects of Natural Capital Protection on Pastoralist's Livelihood and Management Implication in the Source Region of the Yellow River, China 被引量:2
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作者 Fang Yi-ping 《Journal of Mountain Science》 SCIE CSCD 2013年第5期885-897,共13页
The interaction among different livelihood capitals is a key to generate a deeper understanding of the livelihood sustainability.In this paper,we use net income per capita(economic capital),meat and milk production pe... The interaction among different livelihood capitals is a key to generate a deeper understanding of the livelihood sustainability.In this paper,we use net income per capita(economic capital),meat and milk production per capita(physical capital),and areas of fenced pasture,livestock shelter,grassland rodent control and planted grassland(physical capital) as proxy indicators of livelihood promotion,livelihood provision,and livelihood protection respectively.By developing a correlation model between pastoralists' livelihood protection and improvement,we found that(1) there is a statistically significant correlation between the pastoralists' livelihood protection and promotion;(2) based on the maximum effect of pastoralists' livelihood promotion and provision,there is a benchmark in the effect of the intervention intensity of livelihood capital(grassland resource protection) on livelihood improvement;(3) on basis of two indicators,i.e.net income per capita and meat production per capita,the reasonable scales of fenced pasture,livestock shelter and planted grassland are less than 843,860 and 46 thousand hectares(hm2) per year respectively.With the marginal effect of livelihood protection,moderately decreased areas of fenced pasture and planted grassland,and increased area of livestock shelter is a critical to ensure pastoralist's livelihood sustainability. 展开更多
关键词 Regional sustainability Natural capitalprotection Pastoralist's livelihood Source Region ofthe Yellow River
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Protection and Utilization of Ecotourism Resources at the Estuary of the Yellow River
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作者 Weng Senhong Li Weijiong +2 位作者 Liu Yuxin Yu Dehua Xu Hualin 《Ecological Economy》 2005年第3期40-43,共4页
There are plentiful ecotourism resources at the estuary of the Yellow Rive. The characteristic of the resources are vast, wild. rare, peculiar and fresh. Some natural resources, ecotourism resources on the wetland nat... There are plentiful ecotourism resources at the estuary of the Yellow Rive. The characteristic of the resources are vast, wild. rare, peculiar and fresh. Some natural resources, ecotourism resources on the wetland nature reserve of the estuary, and the special landscape ecology resources are introduced in this paper. The author also suggests that the sustainable development of the travel industry at the estuary should be based on the protection and reasonable utilization of the ecosystem. 展开更多
关键词 the estuary of the Yellow River tourism resources protection and utilization
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Effect of Natural Surface Secretes of Some Common Ornamental Plants Leaves on Pathogenic Micro-organisms
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作者 Fouad H. Kamel Hero M. Ismael Akhter A. Ahmed 《Journal of Life Sciences》 2012年第12期1387-1390,共4页
This study presents the antimicrobial effect of natural surface secretes of some common ornamental plants leaves (Ficus elastica, Philodendrom bipinnatifidum and Aglonema) against some pathogenic bacteria ( Escheri... This study presents the antimicrobial effect of natural surface secretes of some common ornamental plants leaves (Ficus elastica, Philodendrom bipinnatifidum and Aglonema) against some pathogenic bacteria ( Escherichia coli, P. aeruginosa and Staph. Aureus), and fungi (Microsporum gypseum and Aspergillus flavus). It was concluded that all tested washing water of the plants leaves secretes exhibited various inhibitory effects, both Philodendrom more antibacterial activity than Ficus elastica. While both E. coli and P bipinnatifidum and Aglonema commutatum had exhibited aeruginosa were being more sensitive than Staph. aureus. The same inhibitory effects were observed when the plants leaves inoculated in their surface with pathogenic bacteria. In contrast to bacterial inhibitory effects, the washing water of natural surface secretes of tested ornamental plants leaves induced mycelium growth of both tested fungi. Microsporum gypseum mycelium growth induced more than Aspergillusflavus especially in case of the washing water of Ficus elastic that have highest effects at 7.5/500 mL of medium. This study concluded the uses of ornamental plants for the indoors and outdoors to control the growth of pathogenic microbes and problems associated with hospital. 展开更多
关键词 Omamental plants natural surface secretes ANTIMICROBIAL pathogenic micro-organism.
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Multiple evidences indicate no relationship between prehistoric disasters in Lajia site and outburst flood in upper Yellow River valley, China 被引量:7
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作者 DONG GuangHui ZHANG FanYu +4 位作者 LIU FengWen ZHANG DongJu ZHOU AiFeng YANG YiShi WANG GongHui 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第4期441-449,共9页
All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Y... All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Yu the Great's flood control has a long history and is considered to be closely linked to the establishment of the Xia Dynasty. However, there is a lack of solid scientific evidence. Against this issue, some scholars have proposed that an earthquake around 1920 BCE in the Guanting Basin along the upper reaches of the Yellow River led to the creation of a lake by damming in the Jishi Gorge and that the outburst of water from that lake led to the massive flood in the Yellow River region. These studies provided new scientific evidence for the Chinese legend. In this paper, we date skeletal samples embedded in earthquake sand blasting from the Lajia site, analyze remains from natural disasters(such as earthquakes and floods) and also archaeological remains. In addition, we compared the skeletal samples dating with that of sediments from the dammed-up lake. Our results are inconsistent with those of previous scholars. The earthquake at the Lajia site occurred no earlier than 1800 BCE, and the dammed-up lake in Jishi Gorge had disappeared by 3600 BCE. Thus, the formation and outburst of the dammed lake, the sudden death of ancient humans at the Lajia site and the ancient earthquake were independent events occurring at different times. In addition, the massive flood in the upper reaches of the Yellow River did not actually happen. Thus, we argue against and invalidate the hypothesis that the massive flood was related to Yu the Great's flood control and the establishment of the Xia Dynasty. 展开更多
关键词 Guanting Basin Qijia culture Lajia site Earthquake Outburst flood The establishment of the Xia dynasty
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Separation of Gold Nanorods Using Density Gradient Ultracentrifugation 被引量:1
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作者 Shuai Li Zheng Chang Junfeng Liu Lu Bai Liang Luo Xiaoming Sun 《Nano Research》 SCIE EI CAS CSCD 2011年第8期723-728,共6页
High quality gold nanorods (NRs) with a monodisperse size and aspect ratio are essential for many applications. Here, we describe how nearly monodisperse gold NRs can be separated from polydisperse samples using den... High quality gold nanorods (NRs) with a monodisperse size and aspect ratio are essential for many applications. Here, we describe how nearly monodisperse gold NRs can be separated from polydisperse samples using density gradient ultracentrifugation. Size and dimension analysis by transmission electron microscopy (TEM) and absorption spectroscopy revealed that the Au NRs were separated mainly as a function of their aspect ratio The surface-enhanced Raman scattering (SERS) activity of Au NRs with lower aspect ratio is notably stronger than that of NRs with higher aspect ratio under 633 nm laser excitation, due to the size-dependent absorption of the longitudinal plasmon band. The separation approach provides a method to improve the quality of NRs produced by large scale synthetic methods. 展开更多
关键词 Au nanorods aspect ratio density gradient SEPARATION surface-enhanced Raman scattering (SERS)
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Study of the temporal and spatial patterns of drought in the Yellow River basin based on SPEI 被引量:21
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作者 Fei WANG Zongmin WANG +1 位作者 Haibo YANG Yong ZHAO 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第8期1098-1111,共14页
Drought is one of the severe natural disasters to impact human society and occurs widely and frequently in China,causing considerable damage to the living environment of humans.The Yellow River basin(YRB)of China show... Drought is one of the severe natural disasters to impact human society and occurs widely and frequently in China,causing considerable damage to the living environment of humans.The Yellow River basin(YRB)of China shows great vulnerability to drought in the major basins;thus,drought monitoring in the YRB is particularly important.Based on monthly data of 124 meteorological stations from 1961 to 2015,the Standardized Precipitation Evapotranspiration Index(SPEI)was used to explore the temporal and spatial patterns of drought in the YRB.The periods and trends of drought were identified by Extreme-point Symmetric Mode Decomposition(ESMD),and the research stages were determined by Bernaola-Galvan Segmentation Algorithm(BGSA).The annual and seasonal variation,frequency and intensity of drought were studied in the YRB.The results indicated that(1)for the past 55 years,the drought in the YRB has increased significantly with a tendency rate of-0.148(10 a)^(-1),in which the area Lanzhou to Hekou was the most vulnerable affected(-0.214(10 a)^(-1));(2)the drought periods(2.9,5,10.2 and 18.3 years)and stages(1961–1996,1997–2002 and 2003–2015)were characterized and detected by ESMD and BGSA;(3)the sequence of drought frequency was summer,spring,autumn and winter with mean values of 71.0%,47.2%,10.2%and 6.9%,respectively;and(4)the sequence of drought intensity was summer,spring,winter and autumn with mean values of 0.93,0.40,0.05 and 0.04,respectively. 展开更多
关键词 Yellow River basin(YRB) Drought Standardized Precipitation Evapotranspiration Index(SPEI) Extreme-point Symmetric Mode Decomposition(ESMD) Bernaola-Galvan Segmentation Algorithm(BGSA)
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