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Effect of ruthenium on γ' precipitation behavior and evolution in single crystal superalloys 被引量:4
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作者 刘丽荣 金涛 +2 位作者 刘金来 孙晓峰 胡壮麒 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期14-22,共9页
The effect of Ru on γ' precipitation behavior and evolution in single crystal superalloys with different Ru contents were investigated by scanning electron microscopy with energy dispersive spectroscopy,3D atomic pr... The effect of Ru on γ' precipitation behavior and evolution in single crystal superalloys with different Ru contents were investigated by scanning electron microscopy with energy dispersive spectroscopy,3D atomic probing,differential scanning calorimetry.The results show that the solvus of the γ' phase decreases gradually with increasing Ru content in the alloys by casting or by the same solution and aging treatments,the alloy with a larger Ru content yields a smaller γ' phase.The addition of Ru increases the growth rate and coarsening rate of the γ' phase.Ru mainly distributes in the γ phase,which causes more Re and Mo partition into the γ' phase,increasing the absolute value of mismatch and the rafting rate of the γ' phase. 展开更多
关键词 single crystal superalloy RUTHENIUM gamma prime PRECIPITATION growth rate coarsening rate MISMATCH
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Variations in tidal currents and suspended sediment concentration of the upper part of the North Channel of Changjiang Estuary over the past 10 years 被引量:1
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作者 刘高伟 程和琴 +3 位作者 计娜 乔远英 胡浩 王冬梅 《Marine Science Bulletin》 CAS 2015年第2期9-24,共16页
The tidal current duration (TCD) and velocity (TCV) and suspended sediment concentration (SSC) were measured in the dry season in December, 2011 and in the flood season in June, 2012 at the upper part of the Nor... The tidal current duration (TCD) and velocity (TCV) and suspended sediment concentration (SSC) were measured in the dry season in December, 2011 and in the flood season in June, 2012 at the upper part of the North Channel of Changjiang Estuary. They were assimilated with the measured data in 2003, 2004, 2006 and 2007, using the tidal range's proportion conversion. Variations in TCD and TCV, preferential flow and SSC have been calculated. Influences of typical engineering projects such as Qingcaosha fresh water reservoir, Yangtze River Bridge, and land reclamation on the ebb and flood TCD, TCV and SSC in the North Channel for the last 10 years are discussed. The results show that: (1) currently, in the upper part of North Channel, the ebb tide dominates; after the construction of the typical projects, ebb TCD and TCV tends to be larger and the vertical average ebb and flood SSC decrease during the flood season while SSC increases during the dry season; (2) changes in the vertical average TCV are mainly contributed by seasonal runoff variation during the flood season, which is larger in the flood season than that in the dry season; the controlling parameters of increasing ebb TCD and TCV are those large-scale engineering projects in the North Channel; variation in SSC may result mainly from the reduction of basin annual sediment loads, large-scale nearshore projects and so on. 展开更多
关键词 changes in tidal currents and suspended sediment concentration preferential flow data assimilation large-scale engineering projects Changjiang Estuary
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Application of EBSD technique to ultrafine grained and nanostructured materials processed by severe plastic deformation:Sample preparation, parameters optimization and analysis 被引量:2
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作者 陈勇军 Jarle HJELEN Hans J.ROVEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期1801-1809,共9页
With the help of FESEM, high resolution electron backscatter diffraction can investigate the grains/subgrains as small as a few tens of nanometers with a good angular resolution (~0.5°). Fast development of EBS... With the help of FESEM, high resolution electron backscatter diffraction can investigate the grains/subgrains as small as a few tens of nanometers with a good angular resolution (~0.5°). Fast development of EBSD speed (up to 1100 patterns per second) contributes that the number of published articles related to EBSD has been increasing sharply year by year. This paper reviews the sample preparation, parameters optimization and analysis of EBSD technique, emphasizing on the investigation of ultrafine grained and nanostructured materials processed by severe plastic deformation (SPD). Detailed and practical parameters of the electropolishing, silica polishing and ion milling have been summarized. It is shown that ion milling is a real universal and promising polishing method for EBSD preparation of almost all materials. There exists a maximum value of indexed points as a function of step size. The optimum step size depends on the magnification and the board resolution/electronic step size. Grains/subgrains and texture, and grain boundary structure are readily obtained by EBSD. Strain and stored energy may be analyzed by EBSD. 展开更多
关键词 electron backscatter diffraction (EBSD) sample preparation parameters optimization step size severe plastic deformation (SPD)
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Long-term variability of the sharp thermocline in the Yellow and East China Seas 被引量:3
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作者 郝佳佳 陈永利 王凡 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第6期1016-1025,共10页
Based on observed temperature data since the 1950s, long-term variability of the summer sharp thermocline in the Yellow Sea Cold Water Mass (YSCWM) and East China Sea Cold Eddy (ECSCE) areas is examined. Relations... Based on observed temperature data since the 1950s, long-term variability of the summer sharp thermocline in the Yellow Sea Cold Water Mass (YSCWM) and East China Sea Cold Eddy (ECSCE) areas is examined. Relationships between the thermocline and atmospheric and oceanic forcing were investigated using multiyear wind, Kuroshio discharge and air temperature data. Results show that: 1) In the YSCWM area, thermocline strength shows about 4-year and 16-year period oscillations. There is high correlation between summer thermocline strength and local atmospheric temperature in summer and the previous winter; 2) In the ECSCE area, interannual oscillation of thermocline strength with about a 4-year period (stronger in El Nifio years) is strongly correlated with that of local wind stress. A transition from weak to strong thermocline during the mid 1970s is consistent with a 1976/1977 climate shift and Kuroshio volume transport; 3) Long-term changes of the thermocline in both regions are mainly determined by deep layer water, especially on the decadal timescale. However, surface water can modify the thermocline on an interannual timescale in the YSCWM area. 展开更多
关键词 THERMOCLINE long-term variability ECS Cold Eddy (ECSCE) YS Cold Water Mass (YSCWM)
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DECADAL CLIMATE VARIABILITY OF RAINFALL AROUND THE MIDDLE AND LOWER REACHES OF THE YANGTZE RIVER AND ATMOSPHERIC CIRCULATION 被引量:1
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作者 王亚非 高桥清利 荣艳淑 《Journal of Tropical Meteorology》 SCIE 2005年第2期169-177,共9页
This study examined the rainfall around the middle and lower reaches of the Yangtze River and related atmospheric circulation by using NCEP reanalysis data. The purpose of this study is to analyze their decadal variat... This study examined the rainfall around the middle and lower reaches of the Yangtze River and related atmospheric circulation by using NCEP reanalysis data. The purpose of this study is to analyze their decadal variation and the relationship among rainfall, atmospheric circulation around East Asia and the ENSO episodes. Current results are presented as follows: (1) Very clear increasing trend of the rainfall around the middle and low reaches of the Yangtze River during the Meiyu period and June to July is found in the recent 15 years. Meanwhile, the geopotential height at 500 hPa around the Okhotsk Sea also holds similar increasing trend. It is noticeable that ENSO episodes tend to occur more frequently in the recent 15 years. (2) An index describing East Asian summer monsoon is well correlated with the SST in the Nino-3 region in preceding autumn in the recent 20 years but is not prior to the period. This means that the El Nino phenomenon exerts more impacts on East Asian summer monsoon recently. (3) The warm phase of PDO in the recent 20 years basically coincides with the increasing trend of the atmospheric circulation in East Asia. 展开更多
关键词 East Asian summer monsoon decadal variation MEIYU
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Precipitation response and hardening behaviors of Fe-modified Ti5553 alloy
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作者 Wen-guang ZHU Pei LI +6 位作者 Xun SUN Wei CHEN Hua-lei ZHANG Qiao-yan SUN Bin LIU Lin XIAO Jun SUN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第6期1242-1251,共10页
Ti5553-xFe (x=0.4, 1.2, 2.0, wt.%) alloys have been designed and fabricated through BE (blended element) sintering to investigate the effect of Fe-addition on athermal ω-phase transformation, α-phase evolution and a... Ti5553-xFe (x=0.4, 1.2, 2.0, wt.%) alloys have been designed and fabricated through BE (blended element) sintering to investigate the effect of Fe-addition on athermal ω-phase transformation, α-phase evolution and age hardening behavior. The results show that the formation of athermal ω-phase is fully suppressed in water-quenched specimens when Fe-addition is up to 2 wt.%. The relevant timescales of α formation during initial stages of aging indicate that incubation time increases with Fe-addition. Further aging results in continuous nucleation and growth of α-phase but finer intragranular α lamellae exhibit in Ti5553-2Fe alloy. In addition, the width and extent of grain boundary α-film increase slightly with incremental Fe-addition, especially in furnace cooling condition. Result of Vickers hardness manifests that Fe-addition leads to a strong hardening effect in both solution and aging treatment. The solid solution strengthening is quantitatively estimated by ab initio calculation based on the Labusch?Nabarro model. The evolution of α-precipitate is rationalized by Gibbs free energy. The prominent hardening effect of Ti5553?2Fe alloy is attributed to both large lattice misfit of β-matrix and fine α-precipitate distribution. 展开更多
关键词 Fe-modified Ti5553 alloy α-phase evolution hardening behavior Pandat calculation
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Separation of growth-stimulating peptides for Bifidobacterium from soybean conglycinin 被引量:8
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作者 Wei-Yong Zuo Wei-Hua Chen Si-Xiang Zou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第37期5801-5806,共6页
AIM: To isolate and identify the soybean conglycinin peptides that selectively stimulates the growth of bifidobacteria in vitro, and to investigate the effect of soybean conglycinin peptides on intestinal ecosystem i... AIM: To isolate and identify the soybean conglycinin peptides that selectively stimulates the growth of bifidobacteria in vitro, and to investigate the effect of soybean conglycinin peptides on intestinal ecosystem in vivo. METHODS: Soybean conglycinin was purified from soybean seeds by gel filtration (Sepharose-CL-6B). These proteins were submitted to hydrolysis by pepsin. Several growth-stimulating peptides for bifidobacteria were isolated chromatographically from pepsin hydrolysis of soybean conglycinin and identified by means of matrixassisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Parallel to in vitro study, in vivo experiments with soybean conglycinin peptides were performed in mice. Ninety male KM mice were randomly assigned into five groups of 16 mice each, and each group was administered for 21d intragastrically with physiological saline (control), conglycinin, pepsin-treated conglycinin (PTC), the most active fraction which isolated from pepsin-treated conglycinin (P2-PTC) and HCl-full hydrolysis of conglycinin (HCl-FHC), respectively. Intestinal microflora were evaluated by standard microbiologic methods and biochemical assays of cecal content samples after treatment. RESULTS: The results showed that the peptides which were isolated from soybean conglycinin could stimulate the growth of bifidobacteria in vitro, and the molecular mass of purified peptides with MALDI-TOF-MS ranged from 693.32 to 1829.55. Compared with control group, in vivo experiments showed that P2-PTC group decreased cecal pH (7.08±0.08 vs7.21±0.09, P〈0.05) and enterococcicounts (5.38±0.26 log10CFU/g vs 5.78±0.19 log10CFU/g, P〈0.05), significantly increased sIgA level (172.08±35.40 ng/g vs 118.27±33.93 ng/g, P〈0.01) and β-galactosidase activity (1.28±0.23 U/g vs 1.82±0.58 U/g, P〈0.05) CONCLUSION: The results have shown that conglycinin is good source for enzyme-mediated production of peptides which stimulate the growth of bifidobacteria. These peptides are inactive within the sequence of the parent protein but can be released during enzymatic hydrolysis, and in vivo experiments demonstrate that conglycinin peptides may be beneficial for improving gastrointestinal health. 展开更多
关键词 Conglycinin pepsin peptides bifidobacteria
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Effects of Salinity on Embryonic Development, Survival, and Growth of Crassostrea hongkongensis 被引量:9
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作者 HUO Zhongming WANG Zhaoping +5 位作者 LIANG Jian ZHANG Yuehuan SHEN Jianping YAO Tuo SU Jiaqi YU Ruihai 《Journal of Ocean University of China》 SCIE CAS 2014年第4期666-670,共5页
This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artific... This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artificial seawater at three different salinities(low, 15; medium, 23; and high, 30) to determine the optimum hatchery and nursery conditions for mass production of the seeds. Results showed that the percentage production of straight-hinged larvae from fertilized eggs was significantly lower at the high salinity than at the low- and medium-salinities(P < 0.05). The survival rates of larvae and juveniles differed significantly among the three salinity trials, with the highest survival rate observed at the low salinity(P < 0.05). The shell height of larvae was significantly larger at the low salinity than at the high and medium salinities from days 9 to 15(P < 0.05), whereas that of juveniles was significantly larger at the low salinity than at the high and medium salinities on day 70(P < 0.05). These results indicate that the larvae and juveniles of C. hongkongensis are tolerant to a wide range of salinities(15 to 30), but show better growth and survival at relatively low salinities. Thus, it is recommended to use relatively low salinities in hatchery and nursery systems for improved yields of C. hongkongensis. 展开更多
关键词 SALINITY embryonic development SURVIVAL GROWTH Crassostrea hongkongensis
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Normalization of plasma growth hormone alleviated malignant ventricular tachycardia in acromegaly
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作者 Zhi-Hao LIU Kang LI +6 位作者 Yan-Sheng DING Jian-Xing QIU Steven Siyao Meng Mohetaboer Momin Sheng-Cong LIU Tie-Ci YI Jian-Ping LI 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第8期547-550,共4页
Acromegaly is an insidious endocrine disease character- ized by chronic elevation of growth hormone (GH) and insulin-like growth factor-1 (IGF-1).Ell Persistent excess se- cretion of GH and IGF-1 damages both card... Acromegaly is an insidious endocrine disease character- ized by chronic elevation of growth hormone (GH) and insulin-like growth factor-1 (IGF-1).Ell Persistent excess se- cretion of GH and IGF-1 damages both cardiac structure and function, leading to acromegalic cardiomyopathy, which is one of the most common causes of increased mortality in acromegaly and can result in an average of 10-year reduction in life expectancy.I2'31 In patients with acromegaly, approximately 3% have been reported having a unique cardiomyopathy characterized by biventricular hypertrophy, myocardial necrosis, lymphocytic infiltration, interstitialfibrosis. 展开更多
关键词 ACROMEGALY Growth hormone IGF-1 Ventricular tachycardia
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Association of overexpression of TIF1γ with colorectal carcinogenesis and advanced colorectal adenocarcinoma 被引量:3
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作者 Shilpa Jain Shashideep Singhal +10 位作者 Franto Francis Cristina Hajdu Jin-Hua Wang Arief Suriawinata Yin-Quan wang Miao Zhang Elizabeth H Weinshel Fritz Francois Zhi-Heng Pei Peng Lee Ru-Liang Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第35期3994-4000,共7页
AIM:To determine the expression and clinical significance of transcriptional intermediary factor 1 gamma (TIF1γ),Smad4 and transforming growth factor-beta (TGFβR) across a spectrum representing colorectal cancer (CR... AIM:To determine the expression and clinical significance of transcriptional intermediary factor 1 gamma (TIF1γ),Smad4 and transforming growth factor-beta (TGFβR) across a spectrum representing colorectal cancer (CRC) development.METHODS:Tissue microarrays were prepared from archival paraffin embedded tissue,including 51 colorectal carcinomas,25 tubular adenomas (TA) and 26 HPs,each with matched normal colonic epithelium.Immunohistochemistry was performed using antibodies against TIF1γ,Smad4 and TGFβ RⅡ.The levels of expression were scored semi-quantitatively (score 0-3 or loss and retention for Smad4).RESULTS:Overexpression of TIF1γ was detected in 5/26 (19%) HP;however,it was seen in a significantly higher proportion of neoplasms,15/25 (60%) TAs and 24/51 (47%) CRCs (P<0.05).Normal colonic mucosa,HP,and TAs showed strong Smad4 expression,while its expression was absent in 22/51 (43%) CRCs.Over-expression of TGFβ RⅡ was more commonly seen in neoplasms,13/25 (52%) TAs and 29/51 (57%) CRCs compared to 9/26 (35%) HP (P<0.05).Furthermore,there was a correlation between TIF1γ overexpression and Smad4 loss in CRC (Kendall tau rank correlation value=0.35,P<0.05).The levels of TIF1γ overexpression were significantly higher in stage Ⅲ than in stage Ⅰ and Ⅱ CRC (P<0.05).CONCLUSION:The findings suggest that over-expression of TIF1γ occurs in early stages of colorectal carcinogenesis,is inversely related with Smad4 loss,and may be a prognostic indicator for poor outcome. 展开更多
关键词 Colorectal cancer Transcriptional intermediary factor 1 gamma Transforming growth factor-beta signaling pathway SMAD4
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Why Bubble Economy Occurs and Crashes? Repeated History of Economic Growth and Collapse 被引量:2
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作者 Eizo Kinoshita 《Chinese Business Review》 2011年第2期102-111,共10页
This paper shows that there are two different phases in economics. These are the primal and dual problems. In the primal problem phase, capital expenditures of private corporations grow, creating an impetus towards th... This paper shows that there are two different phases in economics. These are the primal and dual problems. In the primal problem phase, capital expenditures of private corporations grow, creating an impetus towards the maximization of profits. In this case, as Adam Smith once wrote, the "invisible hand of God" works to lead the economy to a significant growth. This paper defines the concept of economic growth, bubble economy and destruction of bubble economy. And this paper describes why bubble economy occurs and crashes. In the process, this paper shows that primal economy exists before bubble economy and dual economy exists after destruction of bubble economy. 展开更多
关键词 economic growth bubble economy destruction of bubble economy
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Influence of Planting Date on the Growth and Yield of Different Maturity Group of Soybeans in the Southeastern Coastal Plains of USA
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作者 P. Wiatrak G. Chen 《Journal of Agricultural Science and Technology(B)》 2011年第2期251-265,共15页
Planting date is a critical component of soybean [Glycine max (L.) Merr.] production, under dry land conditions in the Southeastern Coastal Plain. The objectives of this study were to 1. Evaluate the effect of plant... Planting date is a critical component of soybean [Glycine max (L.) Merr.] production, under dry land conditions in the Southeastern Coastal Plain. The objectives of this study were to 1. Evaluate the effect of planting date on plant leaf area index (LAI) and normalized difference vegetation index (NDVI) at 60 and 90 days after planting (DAP), plant height and grain yield, and 2. Determine the optimum planting period by integrating the responses from vegetation growth to yield for soybean maturity group (MG) IV-VIII under dry land conditions in the Southeastern Coastal Plain. Planting dates were scheduled about 14-days intervals from late April to mid-July (2008) or late July (2009). Greatest grain yield for MG IV was obtained from planting in around mid-May in both years. The yield was greater for MG V planted in May and greater for MG VI-VIII planted in late April and May, but started to decline for planting in early June. Plant LAI and NDVI at 60 DAP were affected by both planting date and precipitation, but were poorly correlated with grain yield. However, plant LAI and NDVI were well correlated with yield and were greater for May planting dates at 90 DAP. These indiccs declined for soybean planted after May. Mature plant height decreased more rapidly with delayed planting. These results indicate that plant growth and yield decreased after May planting. Optimum planting period for all MGs was early to mid-May. 展开更多
关键词 SOYBEAN planting date leaf area index normalized difference vegetation index grain yield plant growth.
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CO_2 flux and seasonal variability in the turbidity maximum zone and surrounding area in the Changjiang River estuary 被引量:4
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作者 李学刚 宋金明 +3 位作者 袁华茂 李宁 段丽琴 曲宝晓 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第1期222-232,共11页
The turbidity maximum zone(TMZ) is one of the most important regions in an estuary.However,the high concentration of suspended material makes it difficult to measure the partial pressure of CO_2(pCO_2) in these region... The turbidity maximum zone(TMZ) is one of the most important regions in an estuary.However,the high concentration of suspended material makes it difficult to measure the partial pressure of CO_2(pCO_2) in these regions.Therefore,very little data is available on the pCO_2 levels in TMZs.To relatively accurately evaluate the CO_2 flux in an example estuary,we studied the TMZ and surrounding area in the Changjiang(Yangtze) River estuary.From seasonal cruises during February,August,November 2010,and May 2012,the pCO_2 in the TMZ and surrounding area was calculated from pH and total alkalinity(TA)measured in situ,from which the CO_2 flux was calculated.Overall,the TMZ and surrounding area acted as a source of atmosphere CO_2 in February and November,and as a sink in May and August.The average FCO_2was-9,-16,5,and 5 mmol/(m^2·d) in May,August,November,and February,respectively.The TMZ's role as a source or sink of atmosphere CO_2 was quite different to the outer estuary.In the TMZ and surrounding area,suspended matter,phytoplankton,and pH were the main factors controlling the FCO_2,but here the influence of temperature,salinity,and total alkalinity on the FCO_2 was weak.Organic carbon decomposition in suspended matter was the main reason for the region acting as a CO_2 source in winter,and phytoplankton production was the main reason the region was a CO_2 sink in summer. 展开更多
关键词 CO2 flux seasonal variability turbidity maximum zone Changjiang River estuary
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Rifaximin,but not growth factor 1,reduces brain edema in cirrhotic rats 被引量:6
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作者 Gemmaòdena Mireia Miquel +4 位作者 Anna Serafín Amparo Galan Rosa Morillas Ramon Planas Ramon Bartolí 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第17期2084-2091,共8页
AIM:To compare rifaximin and insulin-like growth factor(IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.METHODS:Rats with CCl4-induced cirrhosis with ascites plus portal vein... AIM:To compare rifaximin and insulin-like growth factor(IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.METHODS:Rats with CCl4-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups:Cirrhosis;Cirrhosis + IGF-1;Cirrhosis + rifaximin;Controls;Controls + IGF-1;and Controls + rifaximin.An oral glutamine-challenge test was performed,and plasma and cerebral ammonia,glucose,bilirubin,transaminases,endotoxemia,brain water content and ileocecal cultures were measured and liver histology was assessed.RESULTS:Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups,and improved some liver function parameters(bilirubin,alanine aminotransferase and aspartate aminotransferase).These effects were associated with a significant reduction in cerebral water content.Blood and cerebral ammonia levels,and area-underthe-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group animals.By contrast,IGF-1 administration failed to improve most alterations observed in cirrhosis.CONCLUSION:By reducing gut bacterial overgrowth,only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema,alterations associated with hepatic encephalopathy. 展开更多
关键词 Hyperammonemia Low-grade brain edema Hepatic encephalopathy Rifaximin Insulin-like growth factor 1 Cirrhosis
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Three Gorges Dam Controls Sediment Coarsening of the Mud Patch on the Inner East China Sea Shelf 被引量:2
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作者 MIAO Anyang CHU Zhongxin LI Yingkun 《Journal of Ocean University of China》 SCIE CAS 2016年第3期414-422,共9页
The well-known Three Gorges Dam(TGD) within the Yangtze catchment launched its operation in 2003. The effect of the TGD operation on the sediment size on the East China Sea shelf is rarely known. High resolution(0.5 c... The well-known Three Gorges Dam(TGD) within the Yangtze catchment launched its operation in 2003. The effect of the TGD operation on the sediment size on the East China Sea shelf is rarely known. High resolution(0.5 cm sampling) grain size analysis and 137 Cs and 210 Pb dating of the DH8-1 core were conducted with core collected from the distal part of a main sink for the modern Yangtze sediment entering the sea, the Min-Zhe Coastal Mud Deposits(MZCMD) on the inner East China Sea shelf. The 137 Cs dating results show that the core DH8-1 formed during 1946–2012 with a mean deposition rate of 0.65 cm yr^(-1), indicating that the 0.5 cm sampling for grain size analysis in this local area could reflect environmental changes generally on a one-year time scale. The mean grain size of DH8-1 core sediment that deposited after 2003 is significantly larger than that deposited during 1988–2002. After ruling out other possible factors, we infer that the sediment coarsening of DH8-1 core after 2003 is attributed to the TGD operation which causes the erosion of the Yangtze subaqueous delta. Specifically, the TGD operation significantly intensifies the declining trend of the Yangtze sediment loads to the sea despite no decreased water discharge, which results in extensive erosion of the Yangtze subaqueous delta. The relatively coarse sediment of the subaqueous delta is eroded and resuspended by ocean dynamics and then transported by coastal current, finally depositing on the MZCMD area. In addition, the general sediment fining of core DH8-1 that deposited during 1988–2002, comparing with 1946–1987, is mainly caused by dam construction and soil and water conservation within the Yangtze catchment. Our findings are helpful for better understanding the effects of such a huge dam as the TGD on a sediment sink like the MZCMD of such a large river as the Yangtze River. 展开更多
关键词 Three Gorges Dam environmental effect East China Sea grain size analysis isotopic dating
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Modulation by the Atlantic Multidecadal Oscillation of the intensity of the interannual seesaw between the Somali and Australian cross-equatorial flows
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作者 LI Shuanglin CHEN Ying LI Chen 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第4期306-311,共6页
The decadal variation of the intensity of the interannual opposite connection (seesaw) between the Somali and Australian cross-equatorial flows (CEFs) is investigated. During the period prior to the mid-1960s, and... The decadal variation of the intensity of the interannual opposite connection (seesaw) between the Somali and Australian cross-equatorial flows (CEFs) is investigated. During the period prior to the mid-1960s, and after the early-2000s, the intensity of the interannual seesaw connection is significantly weaker relative to the period between. Such interdecadal shifts in the interannual seesaw intensity bear a resemblance to the decadal shift in ENSO's strength, and can be further attributed to the phase transition of the Atlantic Multidecadal Oscillation (AMO). When the AMO is in a positive phase, the ENSO amplitude reduces and the seesaw strength becomes weakened, and vice versa.The historical simulation outputs of the CMIP5 models are used to verify the connection, and a similar result was obtained. Thus, the notion that the intensity of the interannual opposite connection (seesaw) between the CEFs is modulated by the AMO is robust. 展开更多
关键词 Cross-equatorial flow ENSO Atlantic MultidecadalOscillation East Asiansummer rainfall
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Television as Popular Culture Media and Parental Attention and Their Correlation to the Students' Motivation to Choose Major
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作者 Sudiran 《Sino-US English Teaching》 2015年第5期387-396,共10页
Television as one of the popular culture media plays an important role in the development of students' personality and knowledge because it provides countless information and entertainment that can enhance their know... Television as one of the popular culture media plays an important role in the development of students' personality and knowledge because it provides countless information and entertainment that can enhance their knowledge as the viewers. This study was conducted to give an idea whether television viewing and parental attention can assist students to take a decision of choosing major at the senior high school. This study used descriptive method which analyzed the correlation among television viewing, parental attention, and the students' motivation to choose a major. The sample of this study consisted of 100 students of the state senior high school in Malang, East Java. The finding shows that there is no correlation among television viewing, parental attention, and the students' motivation to choose major at the senior high school. In other words, the possibility of choosing the major can be attributed to some other factors such as interest, talent, aspiration, and other expectation to achieve their goals 展开更多
关键词 TELEVISION popular culture media parental attention students MOTIVATION
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Influence of Irrigation with Reclaimed Water on Antioxidant System of Maize and Soybean
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作者 Zhanbin Huang Wenying Li +4 位作者 Xiaoqing Wang Zhihua Jiao Yang Cao Shengpeng Jing Zhanxia Miao 《Journal of Life Sciences》 2010年第1期32-37,共6页
Irrigation with reclaimed water is an important way to deal with water shortage of agricultural production and solve the problem of sewage pollution. The response of crop antioxidant enzyme system is an early-warning ... Irrigation with reclaimed water is an important way to deal with water shortage of agricultural production and solve the problem of sewage pollution. The response of crop antioxidant enzyme system is an early-warning indicator of environmental factors changes. Compared with raw wastewater and used fresh water as controls, this research studied peroxides (POD), superoxide dismutase (SOD) activities and malondialdehyde (MDA) content in leaves from maize (Zea mays L.) and soybean (Phaseolus vulgaris L.) with pot culture under irrigating with reclaimed water which with secondary and third treatment. The results showed that secondary reclaimed water had some adverse effects on antioxidant system of maize in seedling stage, and the influence decreased in later stage of maize; effect of the third reclaimed water on antioxidant system of maize was not significant. Irrigation with reclaimed water has little influence on antioxidant system of soybean in seedling and reaping stage, but it could bring some oxidative stress in blossom stage. As a result, irrigating maize with second or third reclaimed water is safe to the growth of maize and soybean, but it is suggested that second reclaimed water should not be used in seedling stage of maize and reclaimed water should not be used in the second stage of soybean. 展开更多
关键词 Reclaimed water MAIZE SOYBEAN peroxidase (POD) superoxide dismutase (SOD) malondialdehyde (MDA).
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Variation Trend and Characteristics of Anthropogenic CO Column Content in the Atmosphere over Beijing and Moscow
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作者 WANG Pu-Cai Georgy S.GOLITSYN +4 位作者 WANG Geng-Chen Evgeny I.GRECHKO Vadim S.RAKITIN Ekaterina V.FOKEEVA Anatoly V.DZHOLA 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第3期243-247,共5页
The anthropogenic CO column content in the atmosphere is derived from measurements with infrared grating spectrometers in Beijing,China,and Moscow,Russia,during 1992–2012.Some specific variation characteristics and l... The anthropogenic CO column content in the atmosphere is derived from measurements with infrared grating spectrometers in Beijing,China,and Moscow,Russia,during 1992–2012.Some specific variation characteristics and long-term variation trends of the CO column content in the atmosphere in these regions are discussed.An evident variation trend of anthropogenic CO in the atmosphere for the Beijing region is not observed during 1992–2012,while for the Moscow region,it decreases yearly by about 1.4% for the same period.High CO concentrations appear quite frequently in Beijing,but much less frequently in Moscow,except during the natural fire events in summer 2010.From back trajectory analysis,the high CO concentration observed in Beijing can be attributed to the intensive CO emission sources in its surrounding areas. 展开更多
关键词 ANTHROPOGENIC CO COLUMN contentinfrared GRATING spectrometerair pollution
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基于参量放大器的光通信系统中QC-LDPC码的研究 被引量:1
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作者 郑健 别红霞 +4 位作者 张雪坤 类春阳 房明 李莎 康哲 《光电子.激光》 EI CAS CSCD 北大核心 2014年第1期1-7,共7页
由于光在光纤中传输受到色散的作用以及光纤参量放大器(FOPA)的不理想均会导致光信号在传输过程中的畸变,从而影响光传输系统的误码率(BER)性能。为了减小高非线性光纤(HNLF)和泵浦的影响,本文通过采用由最小环长最大化算法构造的QC-LDP... 由于光在光纤中传输受到色散的作用以及光纤参量放大器(FOPA)的不理想均会导致光信号在传输过程中的畸变,从而影响光传输系统的误码率(BER)性能。为了减小高非线性光纤(HNLF)和泵浦的影响,本文通过采用由最小环长最大化算法构造的QC-LDPC码作为基于FOPA的40Gbit/s非归零差分移相键控(NRZ-DPSK)调制光通信系统的前向纠错码来降低系统的BER,从而达到提高整个通信系统性能的目的。仿真结果表明,在10km传输光纤条件下,相同码长不同码率的QC-LDPC码可以使BER达到10-11数量级;在相同码型和不同传输光纤长度的条件下,BER也可以达到10-11数量级。利用最小环长最大化算法构造的QC-LDPC码可以纠正通信光在传输中受到光纤色散以及FOPA中HNLF和泵浦抖动引起的相位失配而导致的误码,从而达到了提高通信质量的目的。 展开更多
关键词 光参量放大(OPA) QC—LDPC码 最小环大化
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