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CRISPR/Cas9-based functional characterization of Px ABCB1 reveals its roles in the resistance of Plutella xylostella(L.)to Cry1Ac,abamectin and emamectin benzoate
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作者 OUYANG Chun-zheng YE Fan +5 位作者 WU Qing-jun WANG Shao-li Neil CRICKMORE ZHOU Xu-guo GUO Zhao-jiang ZHANG You-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第10期3090-3102,共13页
The identification of functional midgut receptors for pesticidal proteins produced by Bacillus thuringiensis(Bt)is critical for deciphering the molecular mechanism of Bt resistance in insects.Reduced expression of the... The identification of functional midgut receptors for pesticidal proteins produced by Bacillus thuringiensis(Bt)is critical for deciphering the molecular mechanism of Bt resistance in insects.Reduced expression of the PxABCB1 gene was previously found to be associated with Cry1Ac resistance in the diamondback moth,Plutella xylostella(L.).To directly validate the potential receptor role of PxABCB1 and its contribution to Bt Cry1Ac toxicity in P.xylostella,we used CRISPR/Cas9 to generate a homozygous knockout ABCB1KO strain with a 5-bp deletion in exon 3 of its gene.The ABCB1KO strain exhibited a 63-fold resistance to Cry1Ac toxin compared to the parental DBM1Ac-S strain.Intriguingly,the ABCB1KO strain also exhibited significant increases in susceptibility to abamectin and emamectin benzoate.No changes in susceptibility to various other Bt Cry proteins or synthetic insecticides were observed.The knockout strain exhibited no significant fitness costs.Overall,our study indicates that PxABCB1 can protect the insect against avermectin insecticides on one hand,while on the other hand it facilitates the toxic effect of the Bt Cry1Ac toxin.The results of this study will help to inform integrated pest management approaches against this destructive pest. 展开更多
关键词 Bacillus thuringiensis Plutella xylostella CRISPR/Cas9 ABCB1 bioinsecticide resistance
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Evaluation of freezing state of sandstone using ultrasonic time-frequency characteristics
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作者 Jiwei Zhang Julian Murton +4 位作者 Tim Cane Vikram Maji Lili Sui Shujie Liu Song Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期584-599,共16页
Common problems in engineering projects that involve artificial ground freezing of soil or rock include inadequate thickness,strength and continuity of artificial frozen walls.It is difficult to evaluate the freezing ... Common problems in engineering projects that involve artificial ground freezing of soil or rock include inadequate thickness,strength and continuity of artificial frozen walls.It is difficult to evaluate the freezing state using only a few thermometer holes at fixed positions or with other existing approaches.Here we report a novel experimental design that investigates changes in ultrasonic properties(received waveform,wave velocity V_(p),wave amplitude,frequency spectrum,centroid frequency f_(c),kurtosis of the frequency spectrum KFS,and quality factor Q)measured during upward freezing,compared with those during uniform freezing,in order to determine the freezing state in 150 mm cubic blocks of Ardingly sandstone.Water content,porosity and density were estimated during upward freezing to ascertain water migration and changes of porosity and density at different stages.The period of receiving the wave increased substantially and coda waves changed from loose to compact during both upward and uniform freezing.The trend of increasing V_(p) can be divided into three stages during uniform freezing.During upward freezing,V_(p) increased more or less uniformly.The frequency spectrum could be used as a convenient and rapid method to identify different freezing states of sandstone(unfrozen,upward frozen,and uniformly frozen).The continuous changes in reflection coefficient r_(φ),refraction coefficient t_(φ) and acoustic impedance field are the major reason for larger reflection and refraction during upward freezing compared with uniform freezing.Wave velocity V_(p),wave amplitude A_(h),centroid frequency f_(c) and quality factor Q were adopted as ultrasonic parameters to evaluate quantitatively the temperature T of uniformly frozen sandstone,and their application within a radar chart is recommended.Determination of V_(p) provides a convenient method to evaluate the freezing state and calculate the cryofront height and frozen section thickness of upward frozen sandstone,with accuracies of 73.37%-99.23%. 展开更多
关键词 Frozen sandstone Uniform freezing Upward freezing Ultrasonic testing Freezing state
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Contamination by Organochlorine Pesticides in the Estuaries of Southeast China 被引量:13
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作者 Z.L.Zhang H.S.Hong +3 位作者 J.L.Zhou M.H.Dai K.Maskaouib W.Q.Chen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第2期153-160,共8页
Persistent organic pollutants(POPs) such as organochlorine pesticides are of global concern due to their widespread occurrence and persistence. This paper reports recent research studying the distribution and fate of ... Persistent organic pollutants(POPs) such as organochlorine pesticides are of global concern due to their widespread occurrence and persistence. This paper reports recent research studying the distribution and fate of organochlorine pesticides in the Jiulong River, the Minjiang River and the Pearl River estuaries in Southeast China. Eighteen organochlorine pesticides were extracted from water, pore water and sediment samples, followed by analysis by GC ECD. The results showed that the contamination levels were similar in these three estuaries. The levels of the total organochlorine pesticides in porewater were significantly higher than those in surface water, due to the high affinity of these hydrophobic compounds for sediment phase. Among the hexachlorocyclohexane(HCH) compounds, β HCH was found to be the most important isomer. The analysis of 1,1,1 trichloro 2,2 bis chlorophenyl ethane(DDT) and its metabolites showed that 1,1 dichloro 2[ o chlorophenyl] 2[ p chlorophenyl] ethylene(DDE) was dominant in the group. 展开更多
关键词 Organochlorine insecticides DDT LINDANE Jiulong River Estuary Minjiang River Estuary Pearl River Estuary WATER SEDIMENT
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Visualization of Disciplinary Profiles: Enhanced Science Overlay Maps 被引量:7
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作者 Stephen Carley Alan L.Porter +1 位作者 Ismael Rafols Loet Leydesdorff 《Journal of Data and Information Science》 CSCD 2017年第3期68-111,共44页
Purpose: The purpose of this study is to modernize previous work on science overlay maps by updating the underlying citation matrix, generating new clusters of scientific disciplines, enhancing visualizations, and pr... Purpose: The purpose of this study is to modernize previous work on science overlay maps by updating the underlying citation matrix, generating new clusters of scientific disciplines, enhancing visualizations, and providing more accessible means for analysts to generate their own maps Design/methodology/approach: We use the combined set of 2015 Journal Citation Reports for the Science Citation Index (n of journals = 8,778) and the Social Sciences Citation Index (n = 3,212) for a total of 11,365 journals. The set of Web of Science Categories in the Science Citation Index and the Social Sciences Citation Index increased from 224 in 2010 to 227 in 2015. Using dedicated software, a matrix of 227 × 227 cells is generated on the basis of whole-number citation counting. We normalize this matrix using the cosine function. We first develop the citing-side, cosine-normalized map using 2015 data and VOSviewer visualization with default parameter values. A routine for making overlays on the basis of the map ("wc 15.exe") is available at http://www.leydesdorff.net/wc 15/index.htm. Findings: Findings appear in the form of visuals throughout the manuscript. In Figures 1 9 we provide basemaps of science and science overlay maps for a number of companies, universities, and technologies. Research limitations: As Web of Science Categories change and/or are updated so is the need to update the routine we provide. Also, to apply the routine we provide users need access to the Web of Science. Practical implications: Visualization of science overlay maps is now more accurate and true to the 2015 Journal Citation Reports than was the case with the previous version of the routine advanced in our paper.Originality/value: The routine we advance allows users to visualize science overlay maps in VOSviewer using data from more recent Journal Citation Reports. 展开更多
关键词 Science overlay maps Science visualization SCIENTOMETRICS Bibliometrics Interdisciplinary research MULTIDISCIPLINARITY Research policy Research management
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Multi-domain modeling and simulation of proportional solenoid valve 被引量:3
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作者 刘艳芳 戴振坤 +1 位作者 徐向阳 田亮 《Journal of Central South University》 SCIE EI CAS 2011年第5期1589-1594,共6页
A multi-domain nonlinear dynamic model of a proportional solenoid valve was presented.The electro-magnetic,mechanical and fluid subsystems of the valve were investigated,including their interactions.Governing equation... A multi-domain nonlinear dynamic model of a proportional solenoid valve was presented.The electro-magnetic,mechanical and fluid subsystems of the valve were investigated,including their interactions.Governing equations of the valve were derived in the form of nonlinear state equations.By comparing the simulated and measured data,the simulation model is validated with a deviation less than 15%,which can be used for the structural design and control algorithm optimization of proportional solenoid valves. 展开更多
关键词 比例电磁阀 多领域建模 仿真 非线性动力学模型 非线性状态方程 优化控制算法 相互作用 控制方程
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Model Predictive Control of Nonlinear Systems: Stability Region and Feasible Initial Control 被引量:5
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作者 Xiao-Bing Hu Wen-Hua Chen 《International Journal of Automation and computing》 EI 2007年第2期195-202,共8页
This paper proposes a new method for model predictive control (MPC) of nonlinear systems to calculate stability region and feasible initial control profile/sequence, which are important to the implementations of MPC... This paper proposes a new method for model predictive control (MPC) of nonlinear systems to calculate stability region and feasible initial control profile/sequence, which are important to the implementations of MPC. Different from many existing methods, this paper distinguishes stability region from conservative terminal region. With global linearization, linear differential inclusion (LDI) and linear matrix inequality (LMI) techniques, a nonlinear system is transformed into a convex set of linear systems, and then the vertices of the set are used off-line to design the controller, to estimate stability region, and also to determine a feasible initial control profile/sequence. The advantages of the proposed method are demonstrated by simulation study. 展开更多
关键词 Model predictive control (MPC) stability region terminal region linear differential inclusion (LDI) linear matrix inequality (LMI).
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Levels of polycyclic aromatic hydrocarbons in some agricultural, industrial and urban areas along Xiamen coastal waters, China 被引量:4
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作者 MASKAOUI Khalid HU Zhong +1 位作者 ZHOU Jun-liang HAN Ya-li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第2期318-322,共5页
An intensive investigation was conducted to study the distribution of polycyclic aromatic hydrocarbons (PAHs), to show firstly the level of pollution in the agricultural areas and analyses specifically the status of... An intensive investigation was conducted to study the distribution of polycyclic aromatic hydrocarbons (PAHs), to show firstly the level of pollution in the agricultural areas and analyses specifically the status of soil polluted by these persistent pollutants in some locations of Xiamen region. Soil samples collected from Jiulong agricultural catchment have been analysed for 16 PAH compounds, using gas chromatography flame ionization detection in order to determine the level of selected PAH components and to identify the factors that may control their distribution and persistence in the area. The main PAHs found in soil samples were the low molecular weight. The total PAHs detected in soil samples ranged from 0.50 to 0.95 μg/g soil. The highest values of PAHs were significantly detected in the orange tree leaves, which range from 236.1 to 249.3 μg/g soil showing recent atmospheric inputs of these volatile pollutants. The distribution of PAHs in vegetable were monitored and indicating that the concentration were high and ranged from 8.24 to 58.87 μg/g. Other sediment samples were also collected and analysed from urban sewage (5.26 μg/g dw), aquacultural (0.52 μg/g dw) and industrial areas (from 0.62 to 2.09 μg/g dw), during this investigation. The contamination of Jiulong river estuary and Xiamen Western Sea by PAHs has been then widely justified by wastcwatcr discharges and soil runoffs from these areas. The results, therefore, provide important information on the current contamination status caused by the atmospheric transport and point to the need for urgent actions to stop the release of these hydrocarbons to the environment. The necessity of implementing systematic monitoring of PAHs is also emphasized. 展开更多
关键词 PAHS soil Jiulong River Estuary Xiamen Western Sea
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Modeling and Dynamic Analysis for the Foundation of a Blade-Rotor System 被引量:2
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作者 Liang Anyang Huang Guoyuan +1 位作者 Zhang Yuetong Yue Lin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第3期326-332,共7页
In order to achieve the model-based fault monitoring and diagnosis,an accurate model for the rotor system is necessary to locate and quantify faults.Since the dynamic characteristics of a blade-rotor system is influen... In order to achieve the model-based fault monitoring and diagnosis,an accurate model for the rotor system is necessary to locate and quantify faults.Since the dynamic characteristics of a blade-rotor system is influenced by foundation flexibility,the modeling and dynamic analyses on the foundation were sequentially investigated.Firstly,the effect of element size on the model convergence was investigated using the forward difference quotient as the slope of the frequency difference,which found that the model converged when the element size refined to 4mm.Secondly,a modal analysis and a harmonic response analysis were performed to obtain the dynamic characteristics of the foundation structure.Finally,an optimization to the foundation utilizing an additional stiffener was conducted to reduce the foundation response and make the critical speed far away from the working frequency band of 20—50Hz. 展开更多
关键词 finite element model ROTOR modal analysis harmonic response analysis FOUNDATION
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The effect of inlet conditions on the flow and heat transfer in multiple rotating cavity with axial throughflow 被引量:2
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作者 Christopher Long Peter Childs 《航空动力学报》 EI CAS CSCD 北大核心 2007年第5期683-693,共11页
关键词 轴向直流 热转移 旋转式孔 进口接头
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A fast and accurate model for the creation of explosion fragments with improved fragment shape and dimensions 被引量:2
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作者 David Felix Ian Colwill Paul Harris 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第2期159-169,共11页
Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead fragments.However their execution times are extensive.Active protection systems need to make very fast predictions,before a f... Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead fragments.However their execution times are extensive.Active protection systems need to make very fast predictions,before a fast attacking weapon hits the target.Fast execution times are also needed in real time simulations where the impact of many different computer models is being assessed.Hence,FEA explosion models are not appropriate for these real-time systems.The research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an explosion.In addition,the size and shape of fragments,unavailable in Mott’s equation,are calculated using photographic evidence and a distribution of a fragment’s length to its width.The model also identifies the origin of fragments on the warhead’s casing.The results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation steps.The developed model then can be made available for real-time simulation and fast computation. 展开更多
关键词 Distribution of fragments Fragment shape Real-time simulation Cylindrical explosion
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Plateau archives of lithosphere dynamics,cryosphere and paleoclimate:The formation of Cretaceous desert basins in east Asia 被引量:3
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作者 Chihua Wu Juan Pedro Rodríguez-López M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第6期170-181,共12页
Southeastern Eurasia is a global window to the Cretaceous paleoclimate and lithosphere coupling.China contains one of the most complete and complex sedimentary records of Mesozoic desert basins on planet Earth.In this... Southeastern Eurasia is a global window to the Cretaceous paleoclimate and lithosphere coupling.China contains one of the most complete and complex sedimentary records of Mesozoic desert basins on planet Earth.In this study,we perform the spatio-temporal tracking of 96 Cretaceous palaeoclimate indicators during 79 Myr which reveal that the plateau paleoclimate archives from East Asia resulted from an Early to Mid-Cretaceous ocean–atmosphere coupling and a shift to a preponderant role of Late Cretaceous lithosphere dynamics and tectonic forcing on high-altitude depositional systems linked to the subduction margins of the Tethys and Paleo-Pacific realms beneath the Eurasian plate.The crustal response to tectonic processes linked with the spatio-temporal evolution of the Tethyan and Paleo-Pacific margins defined the configuration of major sedimentary basins on this region.The significant increase and decrease in the number of active sedimentary basins that occur during the Cretaceous,from 16 in the Early Cretaceous,to 28 in the Mid-Cretaceous,and a decreasing to 20 sedimentary basins in the Late Cretaceous,is a direct response of lithospheric dynamics associated with the two main subduction zones(Tethys and Pacific domains).A shift in subduction style from an Early Cretaceous Paleo-Pacific Plate slab roll back to a Late Cretaceous flat-slab mode might have triggered regional plateau uplift,blocked intraplate volcanism,thus enhancing the denudation and sediment availability,and created wind corridors that led to the construction and accumulation of extensive Late Cretaceous aeolian sandy deserts(ergs)that covered Mid-Cretaceous plateau salars.At the same time,plateau uplift associated with crustal thickening following terrane assembly in the Tethyan margin triggered altitudinal cryospheric processes in sandy desert systems.Evidence of an active Cretaceous cryosphere in China include ValanginianHauterivian glacial debris flows,Early Aptian geochemical signature of melt waters from extensive ice sheets,and Cenomanian–Turonian ice-rafted debris(IRD).These cryospheric indicators suggest an already uplifted plateau in southeastern Eurasia during the Cretaceous,and the marked correlation between cold plateau paleoclimate archives and marine records suggests a strong ocean-atmosphere coupling during Early and Mid-Cretaceous cold snaps.We thus conclude that lithospheric tectonics during Cretaceous played a fundamental role in triggering high-altitude basin desertification and spatiotemporal plateau paleohydrology variability in the Cretaceous of south-eastern Eurasia. 展开更多
关键词 CRETACEOUS CRYOSPHERE Aeolian PLATEAU Subduction Asia
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Measuring Spatial Differences of Informatization in China 被引量:1
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作者 SONG Zhouying LIU Weidong +2 位作者 MA Li Michael DUNFORD 《Chinese Geographical Science》 SCIE CSCD 2014年第6期717-731,共15页
As the wide application of new Information and Communication Technologies(ICTs) shows, the world is moving fast towards an information age. Since China was first connected to the Internet in 1994, the development of I... As the wide application of new Information and Communication Technologies(ICTs) shows, the world is moving fast towards an information age. Since China was first connected to the Internet in 1994, the development of ICTs in China and around the world has been astonishingly fast, and yet there is a clear ′digital divide′ among different regions in China. Although Chinese geographers have paid attention to regional differences in informatization, they usually employ a limited number of indicators, mainly focusing on the Internet. In fact, informatization is a much broader concept, covering not only the Internet, but also mobile phones as well as user ability. In the light of these considerations, this study provides a comprehensive examination of the development of informatization and its spatial differences in China. First, based on a literature review, the paper identifies 29 preliminary indicators for measuring informatization, and employs principal components analysis and the fuzzy analytic hierarchy process to streamline them into 12 indicators to form an ICTs Development Index(IDI). Second, by using the data from provincial statistical yearbooks and the China Internet Network Information Center, the paper calculates the IDI of each mega-region and each province in 2000–2010, and measures the changing spatial differences in the development of informatization in China. Lastly, the paper quantifies the relationship between informatization and economic growth. The empirical results show that the IDI of the western and central China has been increasing faster than that of the coastal region, indicating that the digital divide in China has been narrowing. 展开更多
关键词 中国互联网络信息中心 空间差异 信息化 信息通信技术 模糊层次分析法 测量信息 TIAL基 中西部地区
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Overconfidence and the adoption of robo-advice:why overconfident investors drive the expansion of automated financial advice 被引量:1
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作者 Dominik M.Piehlmaier 《Financial Innovation》 2022年第1期463-486,共24页
Adaptive online platforms,powered by artificial intelligence,commonly referred to as robo-advice,steadily increase their market share.Yet these comparably new financial services are critically understudied.Little is k... Adaptive online platforms,powered by artificial intelligence,commonly referred to as robo-advice,steadily increase their market share.Yet these comparably new financial services are critically understudied.Little is known about why some investors adopt robo-advice for something as essential as asset allocation.The current paper tries to close this gap by shedding light on the causal effect of investor overconfidence on the propensity of using robo-advice.The study proposes a theoretical framework that combines the divergence of opinion hypothesis with consumer behavior insights and information technology diffusion research.The framework is empirically tested on the Investor Sample of the 2015 National Financial Capability Study,a subsample of 2000 US investors.The results from a series of generalized linear,structural,and semipara-metric models show that in a pre-chasm market,overconfident investors have a significantly higher propensity of adopting robo-advice.While higher financial literacy seems to decrease robo-advice uptake,unjustified confidence in one’s knowledge causally increases it.Willingness to take financial risk cannot account for the significantly increased adoption of robo-advice among overconfident investors.The findings help managers to better position robo-advice by offering behavioral insights into their user base.In addition,the results outline a managerial tool to take demand-side actions to increase the likelihood of an end-user innovation crossing the chasm. 展开更多
关键词 OVERCONFIDENCE Robo-advice Divergence of opinions Diffusion of innovation
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Endotoxins in the prostatic secretions of chronic prostatitis patients:a need for further biomarkers through the use of proteomics
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作者 Sashi S.Kommu Stewart Reiss 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期123-124,共2页
Dear Sir,Dai et al.[1] must be commended on their useful investigation of the clinical significance of endotoxins in the expressed prostatic secretions (EPS) of chronic prostatitis (CP) patients. However, we take ... Dear Sir,Dai et al.[1] must be commended on their useful investigation of the clinical significance of endotoxins in the expressed prostatic secretions (EPS) of chronic prostatitis (CP) patients. However, we take issue with their conclusion. The conclusion that EPS endotoxin determination is helpful in diagnostic confirmation is plausible, 展开更多
关键词 PROTEOMICS Bacterial Infections Biological Markers Chronic Disease ENDOTOXINS Humans Male Prostate PROSTATITIS
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Improved reliability in the interpretation of geochemical measurements by the quantification of uncertainty from sampling
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作者 Michael H. Ramsey Paul D. Taylor Katy A. Boon 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期209-210,共2页
关键词 地球化学 可靠性 土壤 抽样法
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Operating characteristics of a high radius pre-swirl cooling system
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作者 P.New P.R.N.Childs 《航空动力学报》 EI CAS CSCD 北大核心 2007年第6期849-858,共10页
An experimental investigation into pre-swirl effectiveness and receiver hole discharge coefficient characteristics for a high radius injection pre-swirl cooling systems was carried out on a physically representative e... An experimental investigation into pre-swirl effectiveness and receiver hole discharge coefficient characteristics for a high radius injection pre-swirl cooling systems was carried out on a physically representative experimental rig with a 450 mm diameter rotor.The receiver holes and pre-swirl nozzle were located at a radius of 181 mm and 180 mm respectively.The experimental work was mainly conducted at 5 000~12 000 r/min,4 bar absolute pressure and 1.132 kg/s air supply.The maximum air supply temperature was 190 ℃.Pressure and temperature distributions in the pre-swirl system were examined with an emphasis on the velocity effectiveness of the pre-swirl system as a whole and on the discharge coefficients of the rotating 'receiver holes' in the rotor.The results showed that the velocity effectiveness increased with increasing swirl ratio resulting in reduced blade cooling flow temperature.Different seal flow configurations caused very different effectiveness at different speeds,but outflow through the inner and outer seals always gave the highest effectiveness compared other configurations.Increasing the seal flow rate reduced the effectiveness.For the coefficient of discharge,except for the low speed range,it increased with increase in swirl ratio for most speeds. 展开更多
关键词 前漩涡冷却系统 燃气涡轮 速率 流量系数
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Distribution and sources of polycyclic aromatic hydrocarbons in main aquacultural areas in Guangdong, China
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作者 MASKAOUI Khalid 胡忠 +1 位作者 周俊良 韩雅莉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第2期166-173,共8页
The environmental quality status of Daya Bay (22.56–22.77°N, 114.51–114.73°E), a main aquaculture area in Guangdong of China, was investigated using 16 polycyclic aromatic hydrocarbon (PAH) sediment sample... The environmental quality status of Daya Bay (22.56–22.77°N, 114.51–114.73°E), a main aquaculture area in Guangdong of China, was investigated using 16 polycyclic aromatic hydrocarbon (PAH) sediment samples of the bay. The total concentrations of 16 PAHs varied from 115 to 1 134 ng/g dry weight. The PAH composition pattern in sediments suggest dominance of 4-ring PAHs in Sites 2 and 4, and the ratio of certain related PAHs indicated important pyrolytic and petrogenic sources. The results enhance the understanding of current contamination levels and make a better assessment of likely impacts of organic contamination on ecosystems and the sustainability of local aquaculture in the area especially after the establishment of the Nuclear Power Station by the bay. 展开更多
关键词 广东 水产养殖区 多环芳烃 分布 污染源
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Development of polar organic pollutant integrated sampler (POPIS) for trace EDCs in water
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作者 Zulin ZHANG John ZHOU Gang YU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期205-205,共1页
关键词 有机污染物 水体污染 污染化学 POPIS 亲水性
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New Phenomenon of the Hysteresis of 4He in Vycor Glass
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作者 JIN Xin XU Xiaonong +4 位作者 YAN Yong A.L.Thomson D.F.Brewer S.Haynes N.Sharma 《Chinese Physics Letters》 SCIE CAS CSCD 1992年第2期83-85,共3页
The low t emperature part of hysteresis curves of the freezing and melting processes of ^(4)He in vycor glass with the lowest temperature O.4K were measured,as the pressure ranged from 36.45 to 55.18(1O^(5)Pa).Some no... The low t emperature part of hysteresis curves of the freezing and melting processes of ^(4)He in vycor glass with the lowest temperature O.4K were measured,as the pressure ranged from 36.45 to 55.18(1O^(5)Pa).Some novel characteristics of these curves were observed in such high temperature and pressure range.They may result from the existence of superfluid ^(4)He. 展开更多
关键词 FREEZING HYSTERESIS CURVES
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Electronic Properties of CeCuGa
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作者 侯玉敏 金铎 +4 位作者 王玉鹏 雒建林 E.Nyeanchi D.F.Brewer A.L.Thomson 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第1期62-64,共3页
Specific heat in applied magnetic fields were measured to a low temperature 0.08 K and resistance to 0.5K.The specific heat shows a wide peak at 1 K,and a high value of the electronic coefficientγ(T→0)1200 mJ/mol... Specific heat in applied magnetic fields were measured to a low temperature 0.08 K and resistance to 0.5K.The specific heat shows a wide peak at 1 K,and a high value of the electronic coefficientγ(T→0)1200 mJ/mol·K^(2) is obtained.The temperature independence of the wide peak in specific heat at 1K in magnetic fields further suggests that the high valueγof CeCuGa is due to Kondo effect. 展开更多
关键词 RESISTANCE EFFECT INDEPENDENCE
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