期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
Stability and Drag Reduction in Transient Channel Flow of Fibre Suspension 被引量:4
1
作者 游振江 林建忠 +1 位作者 邵雪明 张卫峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第3期319-323,共5页
Drag reduction features in the transition regime of channel flow with fibre suspension were analyzed in terms of the linear stability theory. The modified stability equation was obtained based on the slender-body theo... Drag reduction features in the transition regime of channel flow with fibre suspension were analyzed in terms of the linear stability theory. The modified stability equation was obtained based on the slender-body theory and natural closure approximation. Results of the stability analysis show attenuating effects of fibre additives to the flow instability. For the cases leading to transition, drag reduction rate increases with the characteristic parameter H of fibres. The mechanism of drag reduction by fibres is revealed through the variation of velocity profile and the decrease of wall shear stress. The theoretical results are qualitatively consistent with some typical experiments. 展开更多
关键词 drag reduction flow stability fibre suspension channel flow
在线阅读 下载PDF
Orientation distribution of fibers and rheological property in fiber suspensions flowing in a turbulent boundary layer
2
作者 Jian Zhong Lin Ke Sun Weifeng Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第3期243-250,共8页
A model relating the translational and rotational transport of orientation distribution function (ODF) of fibers to the gradient of mean ODF and the dispersion coefficients is proposed to derive the mean equation fo... A model relating the translational and rotational transport of orientation distribution function (ODF) of fibers to the gradient of mean ODF and the dispersion coefficients is proposed to derive the mean equation for the ODE Then the ODF of fibers is predicted by numerically solving the mean equation for the ODF together with the equations of turbulent boundary layer flow. Finally the shear stress and first normal stress difference of fiber suspensions are obtained. The results, some of which agree with the available relevant experimental data, show that the most fibers tend to orient to the flow direction. The fiber aspect ratio and Reynolds number have significant and negligible effects on the orientation dis- tribution of fibers, respectively. The additional normal stress due to the presence of fibers is anisotropic. The shear stress of fiber suspension is larger than that of Newtonian solvent, and the first normal stress difference is much less than the shear stress. Both the additional shear stress and the first normal stress difference increase with increasing the fiber concentration and decreasing fiber aspect ratio. 展开更多
关键词 Turbulent fiber suspensions Fiber orientation Rheological property Boundary layer Numericalsimulation
在线阅读 下载PDF
Quantifying the Mean Sea Level Change at the Gulf of Finland Coast Caused by the Realistic Portion of the Global Warming Forcing
3
作者 Ali Bassal Mahmood 《Journal of Earth Science and Engineering》 2015年第7期436-448,共13页
Quantifying the coastal mean sea level change causing by the winter positive phase of the North Atlantic oscillation index NAO+ at the Gulf of Finland coast is of high priority for detecting and predicting the global... Quantifying the coastal mean sea level change causing by the winter positive phase of the North Atlantic oscillation index NAO+ at the Gulf of Finland coast is of high priority for detecting and predicting the global warming impact in this region. Both boreal winter months and season of three long-term data station series of the coastal mean sea levels and the NAO indices were linked for two cases, i.e.: different periods and the 1977-1994 period. This study is dedicated to: (1) Detecting the exclusive impacts of the NAO+; (2) Estimating the significant standard bivariate linear regression models; (3) Calculating the climatic linear trend coefficient by using three methods (OLS, GLS, Theil-Sen); (4) Correcting the mean sea level series anomalies by using the significant linear regression equations as a function of NAO+ anomalies, over the period 1977-1994; (5) Calculating the realistic linear trend caused as a function of NAO+ for period 1977-1994 in the context of the realistic portion of the global warming. The results reveal that, the NAO+ manifests their impacts on the coastal mean sea levels and its contribution in the configured linear trends. The realistic linear changes have detected and predicted. The Gulf of Finland coast showed the wannest regions in the context of the realistic portion of the global warming during the winters of the period 1977-1994. 展开更多
关键词 North Atlantic Oscillation Gulf of Finland mean sae level changes.
在线阅读 下载PDF
Orientation distribution of fibres in a channel flow of fibre suspension 被引量:3
4
作者 林建忠 李俊 张卫峰 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2529-2538,共10页
The orientation and concentration distributions of fibres in laminar and turbulent channel flows are investigated numerically. The obtained results are in good agreement with the experimental data. In the laminar flow... The orientation and concentration distributions of fibres in laminar and turbulent channel flows are investigated numerically. The obtained results are in good agreement with the experimental data. In the laminar flow regime, more fibres orient to the flow direction as the Reynolds number increases. The shear rate of fluid around a fibre plays an important role in determining the orientation distribution of fibres, while the fibre density and the fibre aspect-ratio have marginal influence on the orientation distribution. In the turbulent regime, the orientation distribution of fibres becomes more homogeneous with the increase of Reynolds number, and the concentration profile is flatter than that in the laminar regime. The fluctuating intensity of fibre velocity in the downstream direction is larger than that in the lateral directions. 展开更多
关键词 fibres ORIENTATION CONCENTRATION channel flow numerical simulation
在线阅读 下载PDF
Sedimentation of short cylindrical pollutants with mechanical contacts 被引量:2
5
作者 LIN Jian-zhong WANG Ye-long ZHANG Wei-feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期906-911,共6页
Lattice Boltzmann method and elastic particle collision model were used to investigate the sedimentation of short cylindrical pollutant particles with mechanical contacts for varying bulk number density ε and termina... Lattice Boltzmann method and elastic particle collision model were used to investigate the sedimentation of short cylindrical pollutant particles with mechanical contacts for varying bulk number density ε and terminal Reynolds number ReT. The corresponding experiments were performed as a comparison. The clusters of pollutant particles with an inverted “T” structure were observed, the pollutant particles for high ε and large ReT scattered wider than that for low ε and small ReT. The sedimentation velocities increased suddenly at the initial stage, then decreased drastically, after that swayed around and approached to a steady value. The time to steady state did not depend on ε and ReT. The effect of particle interactions was to hinder the average sedimentation velocity, and hindrance was directly proportional to ε. The orientation distributions of pollutant particles depended on ReT and ε, especially on the former. Both the standard deviations of vertical and horizontal velocity, the former was larger than the latter, were nearly independent on ε and ReT. 展开更多
关键词 cylindrical pollutant particles SEDIMENTATION lattice-Boltzmann simulation experiment mechanical contact
在线阅读 下载PDF
ENSO Indices and Analyses 被引量:2
6
作者 王志仁 吴德星 +1 位作者 陈学恩 乔然 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第5期1491-1506,共16页
New ENSO indices were developed and the spatial variability and temporal evolution of ENSO were analyzed based on the new indices and modeling experiments, as well as multiple data resources. The new indices, after be... New ENSO indices were developed and the spatial variability and temporal evolution of ENSO were analyzed based on the new indices and modeling experiments, as well as multiple data resources. The new indices, after being defined, were validated with their good diagnostic characteristics and correlation with wind and SST. In the analysis after the definition and validation of the new indices, ENSO feedbacks from wind, heat fluxes, and precipitation were spatially and temporally examined in order to understand ENSO variability and evolution with some emphasized points such as the interaction among the feedbacks, the role of westerly wind bursts and the transformation between zonal and meridional circulations in an ENSO cycle, and the typical pattern of modern ENSO. 展开更多
关键词 ENSO ENSO indices Walker Circulation westerly wind bursts ENSO feedbacks
在线阅读 下载PDF
The SOOS Asian Workshop on Southern Ocean research and observations 被引量:1
7
作者 LIU Jiping Sebastiaan Swart +4 位作者 Parli V.Bhaskar Louise Newman Michael Meredith Oscar Schofield HE Jianfeng 《Advances in Polar Science》 2014年第2期121-125,共5页
1 Background and purpose of workshop The Southern Ocean plays a fundamental role in the function of the Earth System, influencing climate, sea level, biogeochemical cycles, and biological productivity on a variety of ... 1 Background and purpose of workshop The Southern Ocean plays a fundamental role in the function of the Earth System, influencing climate, sea level, biogeochemical cycles, and biological productivity on a variety of scalesIll. Observations from the Southern Ocean suggest that dramatic changes are taking place, which are of global concern, yet because of its remote location, seasonal sea ice, and harsh environment, the Southern Ocean remains one of the least sampled zones in the world. 展开更多
关键词 Southern Ocean Observing System physical oceanography biological sciences carbon chemistry
在线阅读 下载PDF
Sentinel Site Development of a Major Salt Marsh System in the Mid-Atlantic Region (USA)
8
作者 Michael J. Michael J. Kennish Andrea Spahn Gregg P. Sakowicz 《Open Journal of Ecology》 2014年第3期77-86,共10页
The Tuckerton Peninsula, a large expanse (~2000 ha) of highly inundated Spartina alterniflora salt marsh habitat, forms one of the most extensive coastal wetland systems in New Jersey (USA). It is projected to be amon... The Tuckerton Peninsula, a large expanse (~2000 ha) of highly inundated Spartina alterniflora salt marsh habitat, forms one of the most extensive coastal wetland systems in New Jersey (USA). It is projected to be among the first salt marsh systems in New Jersey to be lost by rising sea level driven by climate change. The changes that occur in the demographic, ecologic, and ecogeomorphic characteristics of the salt marsh habitat at this location will be vital to understanding future habitat change in coastal wetlands in the Mid-Atlantic region. As a consequence, the Tuckerton Peninsula salt marsh system is designated as a sentinel site of the Jacques Cousteau National Estuarine Research Reserve (JCNERR) for the detection, monitoring, and assessment of climate change effects, most notably sea-level rise and inundation. Development of the Tuckerton Peninsula as a sentinel site requires a high accuracy local geodetic control network to connect existing water quality monitoring stations, vegetation transects and monitoring surface elevation tables, ground water wells, and digital elevation models on the same vertical datum. The integration of these monitoring infrastructure components is crucial to effective operation of the sentinel site. It will enable the collection of essential data to assess rates of marsh migration and upland transgression, as well as delineate key natural and anthropogenic drivers influencing habitat condition and change. The JCNERR sentinel site designation supports the National Oceanic and Atmospheric Administration’s long-term goal of assessing coastal vulnerability in the USA to climate change and generating data useful for forging climate adaptation and mitigation initiatives for coastal communities. Habitat and vertical control data collected at this sentinel site will be made available to decision makers across the nation and will enable them to determine how the loss of critical salt marsh habitat will affect coastal communities, their adaptation to future habitat loss, and their development of mitigation plans to address impacts and enhance resiliency. 展开更多
关键词 Tuckerton PENINSULA Salt MARSH SYSTEM VULNERABILITY Climate Change Effects Monitoring Assessment COASTAL Management
在线阅读 下载PDF
Preliminary genetic linkage map of the abalone Haliotis diversicolor Reeve
9
作者 石耀华 郭希明 +2 位作者 顾志峰 王爱民 王嫣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期549-557,共9页
Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596... Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596 AFLP markers were obtained from 28 primer combinations in two parents and 78 offsprings. Among them, 412 markers (15.9%) were polymorphic and segregated in the mapping family. Chi-square tests showed that 151 (84.4%) markers segregated according to the expected 1:1 Mendelian ratio (P<0.05) in the female parent, and 200 (85.8%) in the male parent. For the female map, 179 markers were used for linkage analysis and 90 markers were assigned to 17 linkage groups with an average interval length of 25.7 cm. For the male map, 233 markers were used and 94 were mapped into 18 linkage groups, with an average interval of 25.0 cm. The estimated genome length was 2 773.0 cm for the female and 2 817.1 cm for the male map. The observed length of the linkage map was 1 875.2 cm and 1 896.5 cm for the female and male maps, respectively. When doublets were considered, the map length increased to 2 152.8 cm for the female and 2 032.7 cm for the male map, corresponding to genome coverage of 77.6% and 72.2%, respectively. 展开更多
关键词 amplification fragment length polymorphism (AFLP) genetic linkage map Haliotis diversicolor Reeve
在线阅读 下载PDF
The Interrelation between the NAO (North Atlantic Oscillation) and Regulated River Discharges at the Baltic Sea Drainage Basin
10
作者 Ali Bassal Mahmood 《Journal of Earth Science and Engineering》 2014年第6期331-351,共21页
Both winter DJF (December, January, February) months and DJF season means long-term data series of 50 regulated rivers discharges rates and the NAO indices were analyzed for different spans. This study is dictated ... Both winter DJF (December, January, February) months and DJF season means long-term data series of 50 regulated rivers discharges rates and the NAO indices were analyzed for different spans. This study is dictated for: (1) detecting the exclusive impacts of the positive phases of NAO indices on rivers discharges rates by estimating the Linear Correlation Coefficient; (2) modeling the interrelations between the discharges rates and NAO indices by estimating the Linear Regression Models, both for manifesting the impact of the positive phase of NAO index; (3) estimating the Linear Trend Coefficient in the discharge series, for manifesting the contribution of the positive phase of NAO index. Discharge rates are mainly influenced by the two mechanisms: the positive phase of NAO index and the environmental conditions in specific catchments, that is where, the positive phase of the NAO index manifest its impact on the related rivers discharges and its contribution in the related configured trends. The discharges fluctuations patterns show some increase in the discharges values have been occurred in regions around the Northern Baltic Proper as well as in Southern Finland and Sweden. The rivers such as Lagan, Nissan, Helgean, Venta, Pamu, Porvoonjoki, Lapuanjoki, Oulujoki, Kyronjoki, Wisla, Eurajoki, Odra, Lielupe, Gota alv, Motala strom, Nykopingsan, Vuoksi, Kalajoki and Simojoki haven not linear discharges changes registered depending on the specificity of the environmental conditions at the catchments areas for those rivers. The positive phase of NAO index has a linear relation with impacted river discharge. 展开更多
关键词 River discharge NAO statistical analysis climate.
在线阅读 下载PDF
马氏珠母贝EST微卫星的筛选 被引量:31
11
作者 石耀华 洪葵 +4 位作者 郭希明 王嫣 侯占辉 顾志峰 王爱民 《水产学报》 CAS CSCD 北大核心 2008年第2期174-181,共8页
构建了马氏珠母贝的血液、足、鳃、胃、肝、心脏、外套膜、珍珠囊和感染多毛虫马氏珠母贝的血液(血感)等9个组织的cDNA文库,测序获得了6979个EST序列,从中查找到了268个重复序列,隶属于243个EST,含微卫星的EST数占EST总数的3.48%。珍珠... 构建了马氏珠母贝的血液、足、鳃、胃、肝、心脏、外套膜、珍珠囊和感染多毛虫马氏珠母贝的血液(血感)等9个组织的cDNA文库,测序获得了6979个EST序列,从中查找到了268个重复序列,隶属于243个EST,含微卫星的EST数占EST总数的3.48%。珍珠囊cDNA文库含微卫星的序列所占比例最高,为6.16%,血感的最低,为1.65%。双碱基重复序列130个,占48.5%,(AT/AT)n类型最常见;三碱基类型的83个,占约31%,其中(AAT/ATT)n和(AAG/CTT)n较多;四碱基重复的有30个,占11.2%,(AAAT/ATTT)n占了该类型的约50%。一共能够设计151对微卫星引物,有130对可以扩增,占合成引物总数的86.09%,其中,多态性引物45对。多态性EST-SSR的筛选将为马氏珠母贝的分子遗传学研究、种质鉴定和野生资源保护等提供可靠的工具。 展开更多
关键词 马氏珠母贝 EST—SSR 分子遗传学
在线阅读 下载PDF
长牡蛎(Crassostrea gigas)两个Dmrt家族基因的时空表达 被引量:8
12
作者 张娜 黄雯 +3 位作者 许飞 李莉 张国范 郭希明 《海洋与湖沼》 CAS CSCD 北大核心 2015年第3期717-724,共8页
本文以长牡蛎27个幼虫发育阶段个体以及成体的5个组织织作为实验材料,采用实时荧光定量PCR技术对其Dmrt家族中的2个基因(CgDsx和CgDmrtA2)的表达模式以及在性别决定中的作用进行了研究。结果表明,长牡蛎CgDsx基因在胚胎发育初期有大量表... 本文以长牡蛎27个幼虫发育阶段个体以及成体的5个组织织作为实验材料,采用实时荧光定量PCR技术对其Dmrt家族中的2个基因(CgDsx和CgDmrtA2)的表达模式以及在性别决定中的作用进行了研究。结果表明,长牡蛎CgDsx基因在胚胎发育初期有大量表达,从囊胚期到担轮幼虫初期表达量最高,之后表达量开始降低,在D形幼虫后一直维持在极低的表达水平,此后仅在成体的雄性性腺中具有高度表达。由此可见,CgDsx可能也对早期胚胎发育起一定调控作用,同时参与了性别决定。CgDmrtA2在长牡蛎所有组织中均有表达,各组织间表达差异不显著,在D形幼虫至壳顶后期表达量较高,说明它参与了胚胎中后期的发育过程,可能与神经的形成相关,但是其具体功能还需要进一步研究。 展开更多
关键词 长牡蛎 Dmrt家族 幼虫发育 组织表达差异 性别决定
在线阅读 下载PDF
广西北部湾沿海牡蛎的种类及其分布 被引量:11
13
作者 李翠 王海艳 +2 位作者 刘春芳 李艳伟 郭希明 《海洋与湖沼》 CAS CSCD 北大核心 2013年第5期1318-1324,共7页
采用DNA条形码(DNA barcoding)技术,基于COI基因序列鉴定牡蛎种类,研究了牡蛎科(Ostreidae)牡蛎在广西沿海的分布。本次研究从广西沿海16个采样地点的潮间带共采集550个野生牡蛎样本,随机抽取了367个牡蛎样本进行基因组DNA的提取和线粒... 采用DNA条形码(DNA barcoding)技术,基于COI基因序列鉴定牡蛎种类,研究了牡蛎科(Ostreidae)牡蛎在广西沿海的分布。本次研究从广西沿海16个采样地点的潮间带共采集550个野生牡蛎样本,随机抽取了367个牡蛎样本进行基因组DNA的提取和线粒体COI基因的鉴定,共检测出4属7种牡蛎。巨牡蛎属有4种,分别为熊本牡蛎(Crassostrea sikamea)108个,葡萄牙牡蛎(Crassostrea gigas angulata)43个,香港巨牡蛎(Crassostrea hongkongensis)15个,近江牡蛎(Crassostrea ariakensis)18个,囊牡蛎属(Saccostrea)的多刺牡蛎(Saccostrea echinata)61个,爪蛎属(Talonostrea)的猫爪牡蛎(Talonostrea talonata)112个,齿牡蛎属(Dendostea)的齿缘牡蛎(Dendostea crenulifera)10个。结果表明,广西沿海牡蛎物种丰富,至少7种牡蛎分布于潮间带,其中优势种为猫爪牡蛎和熊本牡蛎,在广西沿海各采样点均有分布。多刺牡蛎和葡萄牙牡蛎次之,香港巨牡蛎、近江牡蛎、齿缘牡蛎数量较少,分布较集中。 展开更多
关键词 广西 牡蛎科 COI 分子鉴定 分布
在线阅读 下载PDF
马里亚纳海沟挑战者深渊南部7000m水深处发现硅藻化石软泥 被引量:5
14
作者 张金鹏 邓希光 +2 位作者 杨胜雄 何高文 朱本铎 《地质通报》 CAS CSCD 北大核心 2015年第12期2352-2354,共3页
在马里亚纳海沟"蛟龙号"载人深潜器海试区约7000m水深的海底,发现了硅藻化石软泥沉积物,为中国首次在此大深度船载采集到硅藻化石软泥。室内硅藻化石分析显示,重力柱状样顶部约10cm厚的软泥为大筛盘藻Ethmodiscus rex硅藻软... 在马里亚纳海沟"蛟龙号"载人深潜器海试区约7000m水深的海底,发现了硅藻化石软泥沉积物,为中国首次在此大深度船载采集到硅藻化石软泥。室内硅藻化石分析显示,重力柱状样顶部约10cm厚的软泥为大筛盘藻Ethmodiscus rex硅藻软泥。化石主要由大筛盘藻组成,呈碎片状,数量巨大,并伴生有Azpeitia等热带远洋浮游种类。硅藻化石软泥发育表明,本区曾发生过E.rex勃发事件,具有重要的古海洋学和古生物学研究意义。 展开更多
关键词 硅藻化石软泥 挑战者深渊 马里亚纳海沟 太平洋
在线阅读 下载PDF
太平洋牡蛎杂交三倍体与诱导三倍体的生长比较 被引量:3
15
作者 孔静 王昭萍 +5 位作者 于瑞海 张跃环 刘剑 李晓瑜 李雅琳 郭希明 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第7期67-71,共5页
本文以中国太平洋牡蛎二倍体自交作为对照,比较了诱导三倍体群体及其杂交三倍体的早期表型性状。通过对各试验组卵径、卵裂率、D幼率、D形幼虫大小、生长、存活率和倍性等指标进行测定,进一步评估了2种诱导方法的有效性。结果表明:与诱... 本文以中国太平洋牡蛎二倍体自交作为对照,比较了诱导三倍体群体及其杂交三倍体的早期表型性状。通过对各试验组卵径、卵裂率、D幼率、D形幼虫大小、生长、存活率和倍性等指标进行测定,进一步评估了2种诱导方法的有效性。结果表明:与诱导三倍体群体相比,杂交三倍体表现出明显优势,D幼率、D形幼虫大小均大于诱导三倍体群体,且差异显著(P<0.05);稚贝期壳长和壳高生长也显著快于诱导三倍体群体(P<0.05)。至附着,杂交三倍体的存活率很高,显著优于诱导三倍体群体。就三倍体率而言,杂交三倍体达到100%,而诱导三倍体群体仅为51.00%±11.79%。由上得知,杂交三倍体更适合应用于大规模生产。 展开更多
关键词 太平洋牡蛎 三倍体 二四倍体杂交 化学诱导
在线阅读 下载PDF
Wave height measurement in the Taiwan Strait with a portable high frequency surface wave radar 被引量:5
16
作者 ZHOU Hao ROARTY Hugh WEN Biyang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第1期73-78,共6页
As an important equipment for sea state remote sensing, high frequency surface wave radar (HFSWR) has received more and more attention. The conventional method for wave height inversion is based on the ratio of the ... As an important equipment for sea state remote sensing, high frequency surface wave radar (HFSWR) has received more and more attention. The conventional method for wave height inversion is based on the ratio of the integration of the second-order spectral continuum to that of the first-order region, where the strong external noise and the incorrect delineation of the first- and second-order Doppler spectral regions due to spectral aliasing are two major sources of errors in the wave height. To account for these factors, two more indices are introduced to the wave height estimation, i.e., the ratio of the maximum power of the second-or- der continuum to that of the Bragg spectral region (RSCB) and the ratio of the power of the second harmonic peak to that of the Bragg peak (RSHB). Both indices also have a strong correlation with the underlying wave height. On the basis of all these indices an empirical model is proposed to estimate the wave height. This method has been used in a three-months long experiment of the ocean state measuring and analyzing ra- dar, type S (OSMAR-S), which is a portable HFSWR with compact cross-loop/monopole receive antennas developed by Wuhan University since 2006. During the experiment in the Taiwan Strait, the significant wave height varied from 0 to 5 m. The significant wave heights estimated by the OSMAR-S correlate well with the data provided by the Oceanweather Inc. for comparison, with a correlation coefficient of 0.74 and a root mean square error (RMSE) of 0.77 m. The proposed method has made an effective improvement to the wave height estimation and thus a further step toward operational use of the OSMAR-S in the wave height extraction. 展开更多
关键词 wave height high frequency surface wave radar field experiment COMPARISON Taiwan Strait
在线阅读 下载PDF
Molecular Characterization of the Calvin Cycle Enzyme Phosphoribulokinase in the Stramenopile Alga Vaucheria litorea and the Plastid Hosting Mollusc Elysia chlorotica 被引量:4
17
作者 Mary E. Rumpho Sirisha Pochareddy +7 位作者 Jared M. Worful Elizabeth J. Summer Debashish Bhattacharya Karen N. Pelletreau Mary S. Tyler Jungho Lee James R. Manhart Kara M. Soule 《Molecular Plant》 SCIE CAS CSCD 2009年第6期1384-1396,共13页
Phosphoribulokinase (PRK), a nuclear-encoded plastid-localized enzyme unique to the photosynthetic carbon reduction (Calvin) cycle, was cloned and characterized from the stramenopile alga Vaucheria litorea. This a... Phosphoribulokinase (PRK), a nuclear-encoded plastid-localized enzyme unique to the photosynthetic carbon reduction (Calvin) cycle, was cloned and characterized from the stramenopile alga Vaucheria litorea. This alga is the source of plastids for the mollusc (sea slug) Elysia chlorotica which enable the animal to survive for months solely by photoautotrophic CO2 fixation. The 1633-bp V. litorea prk gene was cloned and the coding region, found to be interrupted by four introns, encodes a 405-amino acid protein. This protein contains the typical bipartite target sequence expected of nuclearencoded proteins that are directed to complex (i.e. four membrane-bound) algal plastids. De novo synthesis of PRK and enzyme activity were detected in E. chlorotica in spite of having been starved of V. litorea for several months. Unlike the algal enzyme, PRK in the sea slug did not exhibit redox regulation. Two copies of partial PRK-encoding genes were isolated from both sea slug and aposymbiotic sea slug egg DNA using PCR. Each copy contains the nucleotide region spanning exon 1 and part of exon 2 of V litorea prk, including the bipartite targeting peptide. However, the larger prk fragment also includes intron 1. The exon and intron sequences of prk in E. chlorotica and V/itorea are nearly identical. These data suggest that PRK is differentially regulated in V. litorea and E. chlorotica and at least a portion of the V. litorea nuclear PRK gene is present in sea slugs that have been starved for several months. 展开更多
关键词 ALGA Calvin cycle Elysia chlorotica kleptoplast MOLLUSC PHOSPHORIBULOKINASE photosynthesis PLASTID redox regulation stramenopile SYMBIOSIS Vaucheria litorea.
原文传递
Numerical Research on the Fiber Suspensions in a Turbulent T-shaped Branching Channel Flow 被引量:4
18
作者 张善亮 林建忠 张卫峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期30-38,共9页
The concentration and orientation of fiber in a turbulent T-shaped branching channel flow are investi-gated numerically. The Reynolds averaged Navier-Stokes equations together with the Reynolds stress turbulent model ... The concentration and orientation of fiber in a turbulent T-shaped branching channel flow are investi-gated numerically. The Reynolds averaged Navier-Stokes equations together with the Reynolds stress turbulent model are solved for the mean flow field and the turbulent kinetic energy. The fluctuating velocities of the fluid are assumed as a random variable with Gaussian distribution whose variance is related to the turbulent kinetic energy. The slender-body theory is used to simulate the fiber motion based on the known mean and fluctuating velocities of the fluid. The results show that at low Reynolds number, fiber concentration is high in the flow separation regions, and fiber orientation throughout the channel is widely distributed with a slight preference of aligning along the horizontal axis. With increasing of Re, the high concentration region disappears, and fiber orientation becomes ho-mogeneous without any preferred direction. At high Reynolds number, fiber concentration increases gradually along the flow direction. The differences in the distribution of concentration and orientation between different fiber aspect ratio are evident only at low Re. Both Re and fiber aspect ratio have small effect on the variance of orientation angle. 展开更多
关键词 fiber suspension DISTRIBUTION ORIENTATION turbulent branching channel flow numerical simulation
在线阅读 下载PDF
Wave Extraction with Portable High-Frequency Surface Wave Radar OSMAR-S 被引量:2
19
作者 ZHOU Hao ROARTY Hugh WEN Biyang 《Journal of Ocean University of China》 SCIE CAS 2014年第6期957-963,共7页
High frequency surface wave radar(HFSWR) has now gained more and more attention in real-time monitoring of sea surface states such as current, waves and wind. Normally a small-aperture antenna array is preferred to a ... High frequency surface wave radar(HFSWR) has now gained more and more attention in real-time monitoring of sea surface states such as current, waves and wind. Normally a small-aperture antenna array is preferred to a large-aperture one due to the easiness and low cost to set up. However, the large beam-width and the corresponding incorrect division of the first- and second-order Doppler spectral regions often lead to big errors in wave height and period estimations. Therefore, for the HFSWR with a compact cross-loop/monopole antenna(CMA), a new algorithm involving improved beam-forming(BF) and spectral division techniques is proposed. On one hand, the cross-spectrum of the output sequence by the conventional beam-forming(CBF) with all the three elements and the output with only the two loops is used in place of the CMA output self-spectrum to achieve a decreased beam-width; on the other hand, the better null seeking process is included to improve the division accuracy of the first- and second-order regions. The algorithm is used to reprocess the data collected by the portable HFSWR OSMAR-S during the Sailing Competition of the 16 th Asian Games held in Shanwei in November 2010, and the improvements of both the correlation coefficients and root-mean-square(RMS) errors between the wave height and period estimations and in situ buoy measurements are obvious. The algorithm has greatly enhanced the capabilities of OSMAR-S in wave measurements. 展开更多
关键词 HFSWR wave height wave period in situ comparison beam-forming cross-loop
在线阅读 下载PDF
The SOOS Asian Workshop: Exploring possibilities for collaboration
20
作者 Sebastiaan Swart Jiping Liu +4 位作者 Parli Bhaskar Louise Newman Kim Finney Michael Meredith Oscar Schofield 《Advances in Polar Science》 2014年第2期126-132,共7页
The first Southern Ocean Observing System (SOOS) Asian Workshop was successfully held in Shanghai, China in May 2013, attracting over 40 participants from six Asian nations and widening exposure to the objectives an... The first Southern Ocean Observing System (SOOS) Asian Workshop was successfully held in Shanghai, China in May 2013, attracting over 40 participants from six Asian nations and widening exposure to the objectives and plans of SOOS. The workshop was organized to clarify Asian research activities currently taking place in the Southern Ocean and to discuss, amongst other items, the potential for collaborative efforts with and between Asian countries in $OOS-related activities. The workshop was an important mechanism to initiate discussion, understanding and collaborative avenues in the Asian domain of SOOS beyond current established eflbrts. Here we present some of the major outcomes of the workshop covering the principle themes of SOOS and attempt to provide a way forward to achieve a more integrated research community, enhance data collection and quality, and guide scientific strategy in the Southern Ocean. 展开更多
关键词 Southern Ocean observing system ASIA COLLABORATION
在线阅读 下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部