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Experimental investigations of graded sediment transport under unsteady flow hydrographs

International journal of sediment Research 2015年第4期30卷 306-320页

作者： Le Wang alan j.s.cuthbertson Gareth Pender Zhixian Cao Institute for Infrastructure and Environment Heriot-Watt University state Key Laboratory of Water Resources and Hydropower Engineering science Wuhan University

Natural fluvial channels can experience significant variations in sediment transport rates under unsteady flow conditions,especially during flood hydrograph *** present,however,there is a distinct lack of understanding of the interaction between unsteady hydrograph flow properties and temporal variability in graded sediment transport *** the current study,a series of parametric experiments were conducted to investigate the response of two-graded sediment beds to a range of different unsteady hydrograph flow *** of the total and fractional bed-load sediment transport rates revealed strong temporal variations in transport over the hydrographs,with sizedependent temporal lag effects observed between peak flow conditions and peak bed-load transport ***,coarse gravels had increased mobility during the rising limb of the hydrographs,attaining their peak bed-load transport rate either prior to,or near,peak flow *** contrast,the finer grades tended to have enhanced mobility during the receding limb of the hydrographs,with peak transport rates measured after peak flow conditions had *** size distributions measured from the collected bed-load samples also indicated material coarsening over the rising limb and fining during the receding limb,while corresponding image analysis measurements of bed surface composition showed only marginal variation over the *** of total and fractional sediment yields revealed that the bimodal sediment mixture tested was transported at significantly higher rates than the uni-modal mixture over all hydrograph conditions *** finding indicated that the unimodal sediment bed was inherently more stable than the bimodal bed due to the increased abundance of medium-sized gravels present in the uni-modal sediment *** parametric dependences established in the study have clear implications for improved understanding of fractional intergranular effects at the

关键词： Graded sediments Bed-load transport Unsteady flow hydrographs Temporal lag Fractional mobility

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非恒定流驱动下床面形态变化特征

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水科学进展 2021年第5期32卷 751-758页

作者：王乐 alan j s cuthbertson 张尚弘王永强华北电力大学水利与水电工程学院北京102206 school of science and Engineering University of DundeeDundee DD14HNUK 长江科学院水资源综合利用研究所湖北武汉430010

为深入认识非恒定流驱动下床面形态的演变规律及尺度变化趋势,采用水泵控制系统生成了一系列历时与洪峰流量不同的洪水过程来冲刷由粗沙组成的实验动床(中值粒径d 50=1.95 mm),研究中运用非恒定流的形态、非恒定性及水流做功参数来量化... 详细信息

为深入认识非恒定流驱动下床面形态的演变规律及尺度变化趋势,采用水泵控制系统生成了一系列历时与洪峰流量不同的洪水过程来冲刷由粗沙组成的实验动床(中值粒径d 50=1.95 mm),研究中运用非恒定流的形态、非恒定性及水流做功参数来量化洪水过程;统计分析河床高程数据得到床面形态的波长、波高及陡度。实验结果表明:在不同尺度的非恒定流洪水作用下,实验动床表面分别形成了沙垄、交错边滩以及介于两者之间的过渡型床面形态;洪水的非恒定性对床面形态尺度的影响最大,其次是水流做功参数,而非恒定流的形态影响较为微弱;在此基础上构建了用于描述非恒定流驱动条件与床面形态尺度响应的定量关系。

关键词：非恒定流洪水床面形态

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非恒定流驱动下床面形态变化特征研究

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水科学进展 2021年

作者：王乐 alan j s cuthbertson 张尚弘王永强华北电力大学水利与水电工程学院 school of science and Engineering， University of Dundee 长江科学院水资源综合利用研究所

为深入认识非恒定流驱动下床面形态的演变规律及尺度变化趋势，采用水泵控制系统生成了一系列历时与洪峰流量不同的洪水过程来冲刷由粗沙组成的实验动床(中值粒径d50 = 1.95 mm)，研究中运用非恒定流的形态（η）、非恒定性(ΓHG)及水... 详细信息

为深入认识非恒定流驱动下床面形态的演变规律及尺度变化趋势，采用水泵控制系统生成了一系列历时与洪峰流量不同的洪水过程来冲刷由粗沙组成的实验动床(中值粒径d50 = 1.95 mm)，研究中运用非恒定流的形态（η）、非恒定性(ΓHG)及水流做功(Wk)参数来量化洪水过程；统计分析河床高程数据得到床面形态的波长（λ）、波高（D）及陡度（ψ）。实验结果表明：在不同尺度的非恒定流洪水作用下，实验动床表面分别形成了沙垄、交错边滩以及介于两者之间的过渡型床面形态；洪水的ΓHG参数对床面形态尺度的影响最大，其次是参数Wk，而η的影响较为微弱；在此基础上构建了用于描述非恒定流驱动条件与床面形态尺度响应的定量关系。

关键词：非恒定流洪水床面形态

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The integrated use of chemical insecticides and the entomopathogenic nematode, steinemema carpocapsae （Nematoda： steinernematidae）, for the control of sweetpotato whitefly, Bemisia tabaci （Hemiptera： Aleyrodidae）

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Insect science 2008年第5期15卷 447-453页

作者： Andrew G. s. cuthbertson james j. Mathers Phil Northing Anthony j. Prickett Keith F. A. Waiters Central science Laboratory Sand Hutton York YO41 1LZ UK

The integration of chemical insecticides and infective juveniles of the entomopathogenic nematode steinernema carpocapsae （Wesier）（Nematoda： steinernematidae）, to control second instars of the sweetpotato whitefly, Bemisia tabaci Gennadius （Hemiptera： Aleyrodidae） was investigated. Using a sand bioassay, the effects of direct exposure of s. carpocapsae for 24 h to field rate dilutions of four insecticides （spiromesifen, thiacloprid, imidacloprid and pymetrozine） on infectivity to Galleria mellonella larvae were tested. Although all chemicals tested, except spiromesifen, produced acceptable nematode infectivity rates, they were all significantly less than the water control. The effect of insecticide treatment （dry residues of spiromesifen, thiacloprid and pymetrozine and soil drench of imidacloprid） on the efficacy of the nematode against B. tabaci was also investigated. Nematodes in combination with thiacloprid and spiromesifen gave higher B. tabaci mortality （86.5% and 94.3% respectively） compared to using nematodes alone （75.2%） on tomato plants. There was no significant difference in B. tabaci mortality when using the chemicals imidacloprid, pymetrozine and spiromesifen in conjunction with nematodes compared to using the chemicals alone. However, using thiacloprid in combination with the nematodes produced significantly higher B. tabaci mortality than using the chemical alone. The integration of s. carpocapsae and these chemical agents into current integrated pest management programmes for the control of B. tabaci is discussed.

关键词： entomopathogenic nematode infectivity insecticide residue pest management

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TRANsCRIPTION AND TRANsLATION OF ALFALFA LEGHEMOGLOBIN GENEs DURING ROOT NODULE DEVELOPMENT

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science China Chemistry 1990年第9期33卷 1078-1083页

作者：荆玉祥 alan s.PAAU WINsTON j.BRILL Institute of Botany Chinese Academy of Sciences Beijing 100044 PRC Department of Bacteriology and Center for studies of Nitrogen Fixation University of Wisconsin Madison WI 53562 USA Agracetus8520 University GreenMiddletonWI 53562USA

LegHb mRNAs isolated from 2 to 10-week old alfalfa nodules are actively translated in vitro to give a full component of legHb products suggesting that legHb genes, once expressed, are not regulated at the transcription level during the lifetime of a nodule. In vitro translation studies with legHb mRNAs from 10-week old nodules indicate that translation of mRNAs is partially inhibited by addition of alfalfa legHb components themselves and is not promoted by addition of myoglobin and hemoglobin as compared with those of alfalfa legHb mRNAs isolated from 4-week old nodules. This intimates that the regulation of alfalfa legHb synthesis in old nodules at the translation level is weakened.

关键词： leghemoglobin root nodules transeription translation Medicago sativa L. Vernal

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Massive energy storage systems enable secure electricity supply from renewables

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journal of Modern Power systems and Clean Energy 2016年第4期4卷 659-667页

作者： alan j.sANGsTER school of Engineering and Physical sciences Heriot-Watt UniversityRiccarton CampusEdinburgh EH144ASUK

Climate change is mainly attributed to the burning of fossil *** solve the problem,current inhabitants have to dispense with fossil fuels as a source of *** has been demonstrated that this can be secured before 2050 by transitioning to renewable sources of *** energy storage(MEs)incorporated into long distance high voltage direct current(HVDC)transmission systems is the key technology for the *** paper describes the current state-of-the-art in electricity grid *** demonstrates how MEs,and other back-up local electricity storage schemes represent a natural way of buffering electricity consumers from the intermittency of inherent in the primary renewable ***,it can solve the base-load issues and facilitate a global transition to 100%renewable energy sources over the next fifteen to twenty years.

关键词： Electricity grid Energy storage Pumpedhydro Lagoon storage Hydraulic piston Climate change

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Large open-circuit voltage polymer solar cells by poly(3-hexylthiophene) with multi-adducts fullerenes

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science China Chemistry 2012年第5期55卷 743-748页

作者： HEEGER alan j. Department of Physics University of California Santa Barbara USA

Polymer solar cells (PsCs) made by poly(3-hexylthiophene) (P3HT) with multi-adducts fullerenes, [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM), PC61BM-bisadduct (bisPC61BM) and PC61BM-trisadduct (trisPC61BM), were reported. Electrochemistry studies indicated that PC61BM, bisPC61BM and trisPC61BM had step-up distributional lowest unoccupied molecular orbital (LUMO) energy. PsCs made by P3HT with above PC61BMs show a trend of enlarged open-circuit voltages, which is in good agreement with the energy difference between the LUMO of PC61BMs and the HOMO of P3HT. On the contrary, reduced short-circuit currents (jsc) were observed. The investigation of photo responsibility, dynamics analysis based on photo-induced absorption of composite films, P3HT:PC61BMs and n-channel thin film field-effect transistors of PC61BMs suggested that the short polaron lifetimes and low carrier mobilities were response for reduced jsc. All these results demonstrated that it was important to develop an electron acceptor which has both high carrier mobility, and good compatibility with the electron donor conjugated polymer for approaching high performance PsCs.

关键词： fullerene derivative large open circuit voltage polaron lifetime charge carrier mobility

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Bemisia tabaci： The current situation in the UK and the prospect of developing strategies for eradication using entomopathogens

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Insect science 2011年第1期18卷 1-10页

作者： Andrew G. s. cuthbertson Lisa F. Blackburn Dominic P. Eyre Raymond j.C. Cannon judith Miller Phil Northing The Food and Environment Research Agency Sand Hutton York UK

The sweetpotato whitefly, Bemisia tabaci （Gennadius）（Hemiptera： Aleyrodidae） remains a serious threat to crops worldwide. The damaging B-biotype is of specific economic concern because it is an effective vector of over 111 viruses from several fam- ilies, particularly geminiviruses. Bemisia tabaci is regularly intercepted on plants coming into the UK where it is subjected to a policy of eradication. The UK maintains Protective Zone status against this pest. A main pathway of entry of B. tabaci into the Protected Zone involves propagating material, especially Poinsettia （Euphorbia pulcherrima）. With increased insecticide resistance continuously being recorded, B. tabaci is becoming more difficult to control/eradicate. Recent research involving both entomopathogenic nematodes and fungi is showing much potential for the development of control programs for this pest. Both the nematode steinernemafeltiae and the fungus Lecanicillium muscarium have been shown to be most effective against second instar B. tabaci. Fine-tuning of the environmental conditions required has also increased their efficacy. The entomopathogens have also shown a high level of compatibility with chemical insecticides, all increasing their potential to be incorporated into control strategies against B. tabaci.

关键词： biocontrol entomopathogenic nematodes entomopathogenic fungi insecticide resistance whitefly

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Further compatibility tests of the entomopathogenic fungus Lecanicillium muscarium with conventional insecticide products for control of sweetpotato whitefly, Bemisia tabaci on poinsettia plants

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Insect science 2008年第4期15卷 355-360页

作者： Andrew G. s. cuthbertson Lisa F. Blackburn Phil Northing Weiqi Luo Raymond j. C. Cannon Keith F. A. Waiters Central science Laboratory Sand Hutton York Y041 1LZ UK

The effect on spore germination of the entomopathogenic fungus Lecanicillium muscarium following direct exposure for 24 h to the insecticides Majestik, spray Oil, Agri- 50E, savona and Oberon for the control of both egg and second instar stages of the sweetpotato whitefly, Bemisia tabaci, was determined. Exposure to both Agri-50E and Oberon was followed by acceptable spore germination. Infectivity rates ofL. muscarium on poinsettia foliage in the presence of dry residues of the insecticides were also investigated. No significant detrimental effects on the levels of control of B. tabaci were recorded compared with fungus applied to residue-free foliage. sequential application of the chemicals savona, spray Oil and Majestik with the fungus all produced mortalities of second instar B. tabaci above 90%. Incorporation of these chemicals with L. muscarium into integrated control programs for B. tabaci is discussed.

关键词： entomopathogenic fungus integrated pest management insecticidecompatibility Lecanicillium muscarium

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Insulin peptides and their receptors regulate ovarian development and oviposition behavior in Diaphorina citri

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Insect science 2023年第1期30卷 95-108页

作者： Ziye Wang Delong Tan Feifeng Wana shuhao Guo jinhua Liu Andrew G.s.cuthbertson Baoli Qiu Wen sang Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province South China Agricultural UniversityGuangzhouChina Guangdong Laboratory for Lingnan Modern Agriculture GuangzhouChina Institute of Facility Agriculture Guangdong Academy of Agricultural SciencesGuangzhouChina Natural Medicine Institute of Zhejiang YangshengTang Co.LTD HangzhouChina Independent science Advisor YorkUK

Diaphorina citri is an important vector of Citrus Huanglongbing(HLB)*** feeding on young host plant shoots,the population of *** can increase *** also only lay eggs on young ***,there are few studies on the mechanism of this *** nutrient signals can affect the insulin signaling system of *** after feeding on young *** this study,the expression of upstreamfactors DclLPl,DclLP2,and DclR in the insulin signaling system of *** was upregulated after feeding on young *** being silenced by RNA interference technology,the results showed that the number of oviposited eggs of *** was significantly decreased and the ovarian development was inhibited with severe *** addition,detection using quantitative reverse transcription-polymerase chain reaction showed that the upstream regulatory gene DcRheb of the target of rapamycin(TOR)pathway and the downstream reproduction-related DcVg gene were also significantly *** results suggest that feeding upon young shoots may upregulate the expression levels of upstream factors DclLPl,DclLP2,and DclR in the insulin signaling *** signal will be through upregulating the expression of DcRheb,an upstream gene of the TOR signaling *** in turn influences yolk metabolism,which eventually causes the ovaries of female *** to mature and therefore initiate oviposition behavior.

关键词： Diaphorina citri insulin-like peptide insulin receptor insulin signaling reproduction target of rapamycin

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