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RELATIONSHIP BETWEEN DEVELOPMENTS OF THE HUANGHE AND YONGDING RIVERS AND THE EVOLUTION OF THE FOSSIL LAKES OF THE CENOZOIC ERA IN THE DRAINAGE AREA 被引量:5
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作者 李容全 杨明川 《Chinese Geographical Science》 SCIE CSCD 1991年第3期40-53,共14页
The Huanghe and Yongding rivers were formed before the early and middle Pliocene epoch. Then they became interior rivers because of the appearance of interior fault lake basins at the end of the Pliocene epoch. The in... The Huanghe and Yongding rivers were formed before the early and middle Pliocene epoch. Then they became interior rivers because of the appearance of interior fault lake basins at the end of the Pliocene epoch. The interior flow period continued until the end of the early Pleistocene or the middle pf the Middle Pleistocene, and then they changed into the exterior rivers again till today. 展开更多
关键词 the Huanghe RIVER the Yongding RIVER developmentS of a RIVER exterior FLOW period interior FLOW period
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Transcriptome analysis to identify candidate genes related to chlorogenic acid biosynthesis during development of Korla fragrant pear in Xinjiang 被引量:3
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作者 Hao Wen Wenqiang Wang +4 位作者 Xi Jiang Minyu Wu Hongjin Bai Cuiyun Wu Lirong Shen 《Food Science and Human Wellness》 SCIE 2022年第4期854-864,共11页
Korla fragrant pear(KFP)with special fragrance is a unique cultivar in Xinjiang,China.In order to explore the biosynthesis molecular mechanism of chlorogenic acid(CGA)in KFP,the samples at different development period... Korla fragrant pear(KFP)with special fragrance is a unique cultivar in Xinjiang,China.In order to explore the biosynthesis molecular mechanism of chlorogenic acid(CGA)in KFP,the samples at different development periods were collected for transcriptome analysis.High performance liquid chromatography analysis showed that CGA contents of KFP at 88,118 and 163 days after full bloom were(20.96±1.84),(12.01±0.91)and(7.16±0.41)mg/100 g,respectively,and decreased with the fruit development.Pears from these typical 3 periods were selected for de novo transcriptome assemble and 68059 unigenes were assembled from 444037960 clean reads.One‘phenylpropanoid biosynthesis’pathway including 57 unigenes,11 PALs,1 PTAL,64CLs,9 C4Hs,25 HCTs and 5 C3’Hs related to CGA biosynthesis was determined.It was found that the expression levels of 11 differentially expressed genes including 1 PAL,2 C4Hs,34CLs and 5 HCTs were consistent with the change of CGA content.Quantitative polymerase chain reaction analysis further showed that 8 unigenes involved in CGA biosynthesis were consistent with the RNA-seq data.These findings will provide a comprehensive understanding and valuable information on the genetic engineering and molecular breeding in KFP. 展开更多
关键词 Korla fragrant pear development period Chlorogenic acid content De novo transcriptome assembly Phenylpropanoid biosynthesis pathway
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Research on the Development of Rural Commodity Economy in the Edo Period
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作者 Lei YE Lulu QIAN 《Asian Agricultural Research》 2014年第12期1-3,8,共4页
The rural commodity economy in the Edo period developed by leaps and bounds under the influence of institution,policy,technology and other factors. From the mid 17 th century,the specific area of cash crops gradually ... The rural commodity economy in the Edo period developed by leaps and bounds under the influence of institution,policy,technology and other factors. From the mid 17 th century,the specific area of cash crops gradually took shape in Japan and the largescale cultivation of cash crops greatly promoted the development of rural handicrafts,thereby creating the conditions for the initiation of the capitalist relations of production. The development of rural commodity economy not only changed the traditional mode of operation and production of Japanese farmers,but also accelerated the class differentiation,shook and disintegrated the economic foundation and class basis of Bakuhan society,and created the preconditions for the later Meiji Restoration. 展开更多
关键词 EDO period RURAL COMMODITY ECONOMY development CON
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Development of China's Food Industry——Focal Points For China's Food Industry Development During the Ninth Five-Year Plan Period
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《China's Foreign Trade》 1996年第6期18-19,共2页
1.Products of the basic rawmaterials industry Products of the basic raw materialsindustry should improve product quality,make great efforts to realize diversification,serialization and specialization in productvariety... 1.Products of the basic rawmaterials industry Products of the basic raw materialsindustry should improve product quality,make great efforts to realize diversification,serialization and specialization in productvariety,develop new varieties,and expandproduction so as to adapt to the demands forthe development of the food industry. Cereals:Develop high quality riceand wheat flour on a grade and class basis;develop special rice and wheat flour suitablefor the needs of processing various kinds offood;actively utilize coarse cereals such ascorn to open up various kinds of 展开更多
关键词 Co development of China’s Food Industry Focal Points For China’s Food Industry development During the Ninth Five-Year Plan period
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China's Biotech Achievements——Development of China's 863 Program in the Ninth Five-Year Plan Period
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《China's Foreign Trade》 2002年第6期44-45,共2页
Modern biotechnology booms in the molecular life science. It brings about a promising future for improving human health, foodstuff, environment and energy and is of significance to improve traditional agriculture, dru... Modern biotechnology booms in the molecular life science. It brings about a promising future for improving human health, foodstuff, environment and energy and is of significance to improve traditional agriculture, druamakins and other 展开更多
关键词 In China’s Biotech Achievements development of China’s 863 Program in the Ninth Five-Year Plan period gene
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CHINA'S NON-FERROUS METALS INDUSTRY——Its Development Policies and Goals During the Ninth Five-year Plan Period
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作者 Xiao Yuan 《China's Foreign Trade》 1996年第4期40-41,共2页
The China Non-ferrous MetalsIndustry Corporation has putforward ten development policiesfor the Ninth Five-year Plan period,according to the central government’sinstruction to change the way of economicgrowth,and rai... The China Non-ferrous MetalsIndustry Corporation has putforward ten development policiesfor the Ninth Five-year Plan period,according to the central government’sinstruction to change the way of economicgrowth,and raise the integral quality andbenefit of the national economy: 展开更多
关键词 will CHINA’S NON-FERROUS METALS INDUSTRY Its development Policies and Goals During the Ninth Five-year Plan period
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Effects of Different Intercropping Modes on Growth, Yields and Economic Benefit of Cassava and Peanut in Symbiotic Period 被引量:2
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作者 林洪鑫 袁展汽 +4 位作者 刘仁根 肖运萍 汪瑞清 吕丰娟 王子君 《Agricultural Science & Technology》 CAS 2016年第9期2017-2021,2026,共6页
[Objective] This study was conducted to investigate effects of different intercropping modes on growth, yields and economic benefit of cassava and peanut in symbiotic period. [Method] With sole cropping of cassava (M... [Objective] This study was conducted to investigate effects of different intercropping modes on growth, yields and economic benefit of cassava and peanut in symbiotic period. [Method] With sole cropping of cassava (M1) and sole cropping of peanut (M2) as control groups, effects of intercropping of cassava with 1 row, 2 rows and 3 rows of peanut (M3, M4 and M5)on crop growth, yields and economic benefit were studied. [Result] Intercropping affected both growth and yields of cassava and peanut. Growth competition existed between cassava and peanut, and plant heights of cassava and peanut changed similarly. In late stages of intercropping, treatments M1, M2 and M5 showed higher plant heights under no nitrogen application, while treatment M3 and M4 exhibited higher plant heights under nitrogen application; intercropping improved leaf temperature, but no obvious law could be observed among different intercropping treatments; and intercropping improved total dry matter amount, which was the highest in M5 in root expanding stage and on the 30th day of the expanding stage, and the highest in M4 on the 60th day of the expanding stage. Intercropping reduced the yield of single plant, but improved the economic benefit of red upland soil; and under no nitrogen application and nitrogen application, cassava yields decreased by 25.35% and 14.55%, respectively, peanut yields decreased by 28.76% and 52.60%, respectively, while economic benefit increased by 72.90% and 56.82%, respectively. [Conclusion] Compared with sole cropping, interplanting cassava with 1 row, 2 rows or 3 rows of peanut could all improve economic benefit, and the economic benefit increased with number of rows of interplanted peanut increasing. 展开更多
关键词 CASSAVA PEANUT INTERCROPPING Symbiotic period Growth and development
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An Analysis of China's Overall Price Trend During the 12th Five-year Plan Period and Suggestions
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作者 王双正 《China Economist》 2010年第6期120-133,共14页
In this paper,the author first summarizes China’s price operation situation and characteristics since the 1990s,and thenanalyzes inflation shaping factors and types.Based on that,the author raises six inflation early... In this paper,the author first summarizes China’s price operation situation and characteristics since the 1990s,and thenanalyzes inflation shaping factors and types.Based on that,the author raises six inflation early-warning indexes andfully dissects influencing factors of the overall price trend and inflation risks during the 12th Five-year Plan period.Afterthat,the author explains some aspects of price fluctuation that warrants attention during the 12th Five-year Plan period.Finally,the author puts forward policies and suggestions for stabilizing the overall price during the transformation of theeconomic development mode based on our actual situation. 展开更多
关键词 12th Five-year PLAN period overall PRICE level INFLATION TRANSFORMING ECONOMIC development mode
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Histological Observation of Germ Cell Development and Discovery of Spermatophores in Ovoviviparous Black Rockfish(Sebastes schlegeli Hilgendorf) in Reproductive Season 被引量:6
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作者 FENG Junrong LIU Liming +2 位作者 JIANG Haibin WANG Maojian DU Rongbin 《Journal of Ocean University of China》 SCIE CAS 2014年第5期830-836,共7页
Black rockfish(Sebastes schlegeli) is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process... Black rockfish(Sebastes schlegeli) is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process of germ cells in this ovoviviparous rockfish in reproductive season(October 2011–November 2012) with histological methods. We found that the gonad of mature fish showed notable seasonal changes in developmental characteristics and morphological structure. The sperm cells matured during a period lasting from October to December, significantly earlier than the oocytes did. A large number of spermatozoa and other cells occurred in testis at different developmental stages. Vitellogenesis in oocytes began in October, and gestation appeared in April next year. Spermatophores were discovered for the first time in Sebastes, which assembled in testis, main sperm duct, oviduct and genital tract, as well as ovarian cavity in October and April. These organs may serve either as production or hiding places for spermatophores and spermatozoa which were stored and transported in form of spermatophores. Testicular degeneration started from the distal part of testis in April, with spermatophores assembled in degenerating testis and waiting for transportation. The copulation probably lasted for a long period, during which the spermatozoa were discharged in batches as spermatophores. These spermatophores were coated with sticky materials secreted from the interstitial areas of testis and the main sperm duct, then transported into ovary. 展开更多
关键词 Sebastes schlegeli germ cell development SPERMATOPHORE copulation period
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Comparison of protective effects of electroacupuncture and moxibustion at Zusanli(ST 36)on perinatal nicotine exposure-induced lung phenotype in rat offspring
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作者 Yunpeng Ge Yitian Liu +7 位作者 Guozhen Zhao Reiko Sakurai Yana Xie Tianyu Shi Yang Fang Jiajia Wang Virender K.Rehan Bo Ji 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第3期362-369,共8页
Objective:To compare the effects of electroacupuncture(EA)and moxibustion at Zusanli(ST 36)on the lung phenotype of rat offspring exposed to nicotine during the perinatal period.Methods:Pregnant Sprague-Dawley rats we... Objective:To compare the effects of electroacupuncture(EA)and moxibustion at Zusanli(ST 36)on the lung phenotype of rat offspring exposed to nicotine during the perinatal period.Methods:Pregnant Sprague-Dawley rats were randomly divided into 4 groups:the control group(saline only),the model group(nicotine only),the EA group(nicotine+EA at ST 36 acupoints bilaterally),and the moxibustion group(nicotine+moxibustion at ST 36 acupoints bilaterally).n=6 rats per group.On postnatal day 21,the body weight,lung weight,and pulmonary function were determined and lung morphometry was performed.Peroxisome proliferator-activated receptor gamma andβ-catenin levels in the lung tissue of offspring were also determined.Results:Perinatal nicotine exposure(PNE)results in decreased body and lung weights of offspring rats,abnormal lung tissue morphology,and significantly altered pulmonary function,showing an increase in total airway resistance and a decrease in tidal volume,minute ventilation,total airway compliance,and peak expiratory flow.Bilateral EA at ST 36 acupoints could block all of these perinatal nicotine-induced effects.Although moxibustion also had protective effects in nicotine-induced offspring lungs,some of these effects did not reach statistical significance,e.g.,protection against the upregulation ofβ-catenin,the downregulation of PPARγsignaling,and the increase in peak expiratory flow.Conclusion:Maternal EA at ST 36 blocked the PNE-induced changes in key developmental signaling pathways,prevented the PNE-induced changes in lung morphology,and protected pulmonary function.Moxibustion at ST 36 showed similar but weaker protective effects against the PNE-induced changes in the exposed offspring.It is important to note that the mechanism underlying the protective effects of moxibustion at ST 36 may be different from those of EA at ST 36,and further research is needed to understand these differences. 展开更多
关键词 Electroacupuncture Moxibustion Perinatal period Nicotine exposure Lung development Zusanli(ST 36) PPARγ β-catenin
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Economists’Judgement on China’s Socio-Economic Development in the 14th Five-Year Plan Period 被引量:2
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作者 Editorial Division of China Economist Chen Sumei 《China Economist》 2020年第4期64-99,共36页
2020 is the final year of China’s 13th Five-Year Plan period and an intersection between the“two centennial goals.”It is also a vital year for drafting the 14th Five-year Plan and embarking on a new journey of soci... 2020 is the final year of China’s 13th Five-Year Plan period and an intersection between the“two centennial goals.”It is also a vital year for drafting the 14th Five-year Plan and embarking on a new journey of socialist modernization.What socio-economic progress has China achieved during the 13th Five-Year Plan period and what are the opportunities,challenges and countermeasures for the 14th Five-Year Plan period?In May 2020,the China Economist conducted a questionnaire survey among economists.Results suggest that during the 13th Five-Year Plan period,China has achieved remarkable progress in the following areas:significant socio-economic development,deepening industry-ICT integration,and rapid growth of new economy;mass entrepreneurship and mass innovation,and enhanced R&D capabilities for cutting-edge technologies;green production and the abatement of air and water pollution;and poverty reduction.In the 14th Five-Year Plan period,opportunities co-exist with challenges for China’s socio-economic development,which brims with resiliency.Surveyed economists felt sanguine about China’s development outlook.Based on the results,surveyed economists believed that the Chinese government should focus on the following priorities during the 14th Five-Year Plan period:expediting industrial transition,strengthening the real economy,and exploring domestic consumption potentials;ramping up research in fundamental science,and accelerating the research of critical technologies;increasing equal access to basic public services;and promoting green development in all respects,including green consumption,production,distribution,innovation,and finance. 展开更多
关键词 14th Five-Year Plan period economic development innovation-led growth public welfare environmental protection
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Suggestions on the Effective Development of Shale Gas in China 被引量:2
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作者 Cao Yan Yang Kefeng +1 位作者 Jing Keyao Hu Yan 《China Oil & Gas》 CAS 2018年第4期18-25,共8页
Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distr... Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distribution, a low abundance,unfavorable reservoir conditions, ultra-low permeability and a fast production decline, shale gas is more difficult to develop than conventional natural gas, as it needs advanced drilling and completion technology to develop. During the early stage of shale gas exploration and development, the United States offered enterprises necessary incentives such as tax reductions and exemptions and subsidies to achieve sustainable shale gas development and encourage technological progresses. By comparing the state of China's shale gas development with that of the US' in terms of geological conditions, production technology,market price, tax relief, subsidy periods and amount, this paper intends to put forward related suggestions for the effective development of shale gas according to the current status of development. 展开更多
关键词 Unconventional resource Shale gas Effective development Subsidy period SUBSIDY SUGGESTION
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The spatio-temporal models of periodic marketing in rural China
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作者 LIU Sheng-he(Institute of Geography, Chinese Academy of Sciences. Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第4期335-345,共11页
Periodic marketing is a unique and imporant socio-economic feature of Chinese ruraltowns, the economic, political, social and cultural centres in rural areas. Through two detailed casestudies in the North China Plain... Periodic marketing is a unique and imporant socio-economic feature of Chinese ruraltowns, the economic, political, social and cultural centres in rural areas. Through two detailed casestudies in the North China Plain in 1990, mis paper examined the temporal and spatialcharacteristics, especially their interrelationship. of regional periodic market systems and theirrelationship with rural development in modern China. The distribution of periodic market-towns isfound to be on consumer convenience, and to have an apparent hierarchical structure and centralplace characteristics. Further, the spatial coordination system of periodic marketing has a reverserelationship of spatio-temporal synchronisation. Finally, this paper notes that periodic marketingimposes significant influence on rural development through conducting and controlling goods flow and population flow in rural economic system. 展开更多
关键词 periodic marketing spatio-temporal synchronisation rural development
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Abandoned Mine, Potential Home for the People: A Case Study of Jos Plateau Tin-Mining Region
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作者 Samuel Danjuma Wapwera Grace Mebi Ayanbimpe Charles Egbu Odita 《Journal of Civil Engineering and Architecture》 2015年第4期429-445,共17页
This paper seeks to examine the JPTMR (Jos Plateau Tin-Mining Region) as an abandoned mine that provides land for housing by examining the impact of the tin-mining activities due to the presence of heavy metals and ... This paper seeks to examine the JPTMR (Jos Plateau Tin-Mining Region) as an abandoned mine that provides land for housing by examining the impact of the tin-mining activities due to the presence of heavy metals and radioactive substances and analyzing the level and availability of these substances and their effects on human health and the built environment within JPTMR. Utilizing secondary data, which map out 10 different locations in the region, the paper highlights the level of radioactive substances (X-ray, beta-ray and gamma-ray) and presence of heavy metals in the environment. The results show that there are traces of X-ray, beta-ray and gamma-ray as well as the heavy metals such as Pb, As, Cu, Cr and Ni which exceeded the international standards. This is particularly significant as people use the contaminated soils as building materials for their homes as well as for farming and food production. The inhabitants of the area are often without any knowledge about the perils of the contaminated soils, water as well as air which is serious long-term human catastrophe. Drawing from international experience, the paper argues that it is possible to develop housing in former tin-mining areas but requires careful remediation and engagement by the public and private sector. 展开更多
关键词 Abandoned mines contaminated land housing development home.
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China's Strategic Measures to Develop Coal Industry During the Period of the Ninth Five-Year Plan
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《China's Foreign Trade》 1996年第10期26-27,共2页
A reporter for China’s Foreign Tradehas learned from the Ministry of theCoal Industry that China will takethe following steps to develop its coal industryduring the ninth five-Year plan period. 1. To regulate the pol... A reporter for China’s Foreign Tradehas learned from the Ministry of theCoal Industry that China will takethe following steps to develop its coal industryduring the ninth five-Year plan period. 1. To regulate the policy for buildupthe coal industry and to make a good job ofthe comprehensive development of buildinga number of key coal production bases. 展开更多
关键词 In will China’s Strategic Measures to Develop Coal Industry During the period of the Ninth Five-Year Plan
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China's Biotechnology Development Program during the Tenth Five-Year Plan Period (2001-2005)
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《China's Foreign Trade》 2002年第6期46-46,共1页
Bioengineering TechnoIogy(Ⅰ)1. Crop molecular marker-assisted selection and pyramiding breeding technology2. Super hybrid
关键词 high China’s Biotechnology development Program during the Tenth Five-Year Plan period
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Western China Development During 13th Five-Year Plan Period:Poverty Alleviation and Green Development
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《Ecological Economy》 2016年第4期384-385,共2页
The 12th Annual Conference of the Consortium for Western China Development Studies July,2017Gui-An New District,CHINABackground Since its establishment in 2004,the Consortium for Western China Development Studies(CWCD... The 12th Annual Conference of the Consortium for Western China Development Studies July,2017Gui-An New District,CHINABackground Since its establishment in 2004,the Consortium for Western China Development Studies(CWCDS)has organized nine conferences on vari- 展开更多
关键词 office TEL Western China development During 13th Five-Year Plan period
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Time-Frequency and Nonlinear Analysis of Tidal Data Observed on the Kuroshio Path
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作者 Kenta Kirimoto 《International Journal of Modern Nonlinear Theory and Application》 2016年第4期147-159,共13页
The tidal data of Kushimoto and Uragami on flow path of Kuroshio from 2004 to 2005 are investigated and discussed by time-frequency methods and nonlinear methods in this paper. These analyzing methods based on mathema... The tidal data of Kushimoto and Uragami on flow path of Kuroshio from 2004 to 2005 are investigated and discussed by time-frequency methods and nonlinear methods in this paper. These analyzing methods based on mathematical science show us new findings about the tidal motion observed on Kuroshio flow path. On the time-frequency analysis, 12 hours component and 24 hours component swing during the period of 350 hours and 320 hours respectively. However, any remarkable differences or changes depending on Kuroshio flow path weren’t seen on the result of time-frequency analysis. On the nonlinear analysis, a periodical structure has seen on the mutual information of tidal difference data, while Kuroshio flow is stable. In addition, the mutual information showed a characteristic of randomness and irregularity, while Kuroshio flow is unstable. The important results brought us a new finding such as classification of tidal motion regardless of the flow path of Kuroshio. 展开更多
关键词 Wavelet Transform Lorenz’s Plot Mutual Information Time development periodICITY IRREGULARITY Classification
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Towards high strength cast Mg-RE based alloys:Phase diagrams and strengthening mechanisms 被引量:6
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作者 Janet M.Meier Josh Caris Alan A.Luo 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第6期1401-1427,共27页
Mg-rare earth(RE)based systems provide several important commercial alloys and many alloy development opportunities for high strength applications,especially in aerospace and defense industries.The phase diagrams,micr... Mg-rare earth(RE)based systems provide several important commercial alloys and many alloy development opportunities for high strength applications,especially in aerospace and defense industries.The phase diagrams,microstructure,and strengthening mechanisms of these multicomponent systems are very complex and often not well understood in literature.We have calculated phase diagrams of important binary,ternary,and multicomponent RE-containing alloy systems,using CALPHAD(CALculation of PHAse Diagrams).Based on these phase diagrams,this paper offers a critical overview on phase equilibria and strengthening mechanisms in these alloy systems,including precipitation,long period stacking order(LPSO),and other intermetallic phases.This review also summarized several promising Mg-RE based cast alloys in comparison with commercial WE54 and WE43 alloys;and explored new strategies for future alloy development for high strength applications.It is pointed out that the combination of precipitation and LPSO phases can lead to superior strength and ductility in Mg-RE based cast alloys.The precipitates and LPSO phases can form a complex three-dimensional network that effectively impedes dislocation motion on the basal and non-basal planes.The LPSO phases can also prevent the coarsening of precipitates when they interact,thus providing good thermal stability at elevated temperatures.Future research is needed to determine how the combination of these two types of phases can be used in alloy design and industrial scale applications. 展开更多
关键词 Magnesium alloys Phase diagrams Precipitation strengthening Long period stacking order(LPSO) Alloy development CALPHAD
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Phase equilibria and microstructure investigation of Mg-Gd-Y-Zn alloy system 被引量:1
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作者 Janet M.Meier Jiashi Miao +4 位作者 Song-Mao Liang Jun Zhu Chuan Zhang Josh Caris Alan A.Luo 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第3期746-755,共10页
In order to develop high strength Mg-Gd-Y-Zn alloys,key experiments coupled with CALPHAD(CALculation of PHAse Diagrams)calculations were carried out in the current work to provide critical understanding of this import... In order to develop high strength Mg-Gd-Y-Zn alloys,key experiments coupled with CALPHAD(CALculation of PHAse Diagrams)calculations were carried out in the current work to provide critical understanding of this important alloy system.Three Mg-10 Gd-xY-yZn(x=4 or 5,y=3 or 5,wt.%) were mapped on Mg-Gd-Y-Zn phase diagrams for phase equilibria and microstructure investigation.Electron microscopy was performed for phase identification and phase fraction determination in as-cast and solution treated conditions.In all three alloys,the major phases were Mg-matrix and long period stacking order(LPSO) 14 H phase.With ST at 400 and 500℃,the phase fraction of LPSO 14 H increased,particularly the fine lamellar morphology in the Mg matrix.The as-cast and 400℃ Mg10 Gd5 Y3 Zn samples had Mg(Gd,Y) present.At 500℃,Mg(Gd,Y) is not stable and transforms into LPSO 14 H.The Mg 10 Gd5 Y5 Zn alloy included the WPhase,which showed a reduction in phase fraction with solution treatment.These experimental results were used to validate and improve the thermodynamic database of the Mg-Gd-Y-Zn system.Thermodynamic calculations using the improved database can well describe the available experimental results and make accurate predictions to guide the development of promising high-strength Mg-Gd-Y-Zn alloys. 展开更多
关键词 Long period stacking order(LPSO) MICROSTRUCTURE Magnesium alloys CALPHAD Alloy development.
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