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Episodes 2004年第1期27卷 21-32页

作者： W.J.kennedy A.S.Gale J.A.Lees m.Caron OxfordUniversitymuseumofNaturalHistory ParksRoadOxfordOXI3PWU.K. DepartmentofPalaeontology TheNaturalHistoryMuseumCromwellRoadLondonSW75BPU.K.andSchoolofEarthandEnvironmentalSciencesUniversityofGreenwichChathamMaritimeCampusChathamKentME44AWU.K. ResearchSchoolofGeologicalandGeophysicalSciences BirkbeckCollegeandUniversityCollegeLondonGowerStreetLondonWCIE6BTU.K. InstitutdeGeologie UniversitedeFribourgCH-1700FribourgSwitzerland.

Following the unanimous recommendation of the International Commission on Stratigraphy, the Global boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage is defined at a level 36 metres below the top of the marnes Bleues Formation, a level that corresponds to the the first appearance of the planktonic foraminiferan Rotalipora globotruncanoides Sigal, 1948, on the south side of mont Risou, east of Rosans, Haute-Alpes, France, where it can be placed in the context of a series of secondary marker levels based on nannofossils, planktonic foraminifera, ammonites,and an ornate δ^13C curve.

关键词：地层学地层分界线层型地质构造

Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction

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Defence Technology（防务技术） 2024年第4期34卷 328-338页

作者： Yangtian Liu Xiaopeng Yan Qiang Liu tai An Jian Dai Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China China Research and Development Academy of machinery Equipment Beijing 100089China

The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference ***,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio *** solve the above problem,a radio fuze automatic modulation recognition(AmR)method for low-SNR environments is ***,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)***,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCms),and support vector machines(SVms)are used for *** DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical *** trained SVm classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AmR performance of radio fuzes under low SNRs.

关键词： Automatic modulation recognition Adaptive denoising Data rearrangement and the 2D FFT(DR2D) Radio fuze

Effect of Biochar Addition on maize Growth and Nitrogen Use Efficiency in Acidic Red Soils

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Pedosphere 2014年第6期24卷 699-708页

作者： ZHU Qiao-Hong PENG Xin-Hua HUANG tai-Qing XIE Zu-Bin N.m.HOLDEN State key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of Sciences University of Chinese Academy of Sciences UCD School of Biosystems Engineering Agriculture and Food Science CentreUniversity College Dublin

Biochar added to soil can improve crop growth through both direct and indirect effects, particularly in acidic, highly weathered soils in subtropical and tropical regions. However, the mechanisms of biochar improving crop growth are not well understood. The objectives of this study were i) to determine the crop responses to biochar addition and ii) to understand the effect of biochar addition on N use efficiency. Seven acidic red soils varying in texture, p H, and soil nutrient were taken from southern China and subjected to four treatments: zero biochar and fertilizer as a control(Ck), 10 g kg-1biochar(BC), NPk fertilizers(NPk), and 10 g kg-1biochar plus NPk fertilizers(BC+NPk).15N-labeled fertilizer was used as a tracer to assess N use efficiency. After a 46-d pot experiment,biochar addition increased soil p H and available P, and decreased soil exchangable Al3+, but did not impact soil availabe N and cation exchange capacity(P > 0.05). The N use efficiency and N retained in the soil were not significantly affected by biochar application except for the soil with the lowest available P(3.81 mg kg-1) and highest exchanageable Al3+(4.54 cmol kg-1). Greater maize biomass was observed in all soils amended with biochar compared to soils without biochar(BC vs. Ck, BC+NPk vs. NPk). This agronomic effect was negatively related to the concentration of soil exchangeable Al3+(P mplied that the liming effect of biochar improved plant growth through alleviating Al toxicity and P deficiency, especially in poor acidic red soils.

关键词： agronomic effect AI toxicity liming effect, ^15N labeling P deficiency

Precision cardiovascular medicine in China

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Journal of Geriatric Cardiology 2020年第10期17卷 638-641页

作者： Jie LIU Ru-tai HUI Lei SONG State key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Cardiomyopathy Ward National Clinical Research Center for Cardiovascular DiseasesFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

1 Introduction In China's mainland,hospitalization expenses for patients with cardiovascular and cerebrovascular diseases have rapidly increased since 2004 and currently exceed the growth rate of the national gross domestic product.[1]One reason for these high expenses is that the traditional"one-size-for-all"medical model results in low treatment *** and individualized medical models may help reduce the medical burden and provide a sustainable medical model.

关键词： Cardiovascular disease Challenges Precision medicine Progress

Bubble performance of a novel dissolved air flotation(DAF) unit

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Journal of Environmental Sciences 2004年第1期16卷 104-107页

作者： CHENFu-tai PENGFeng-xian WUXiao-qing LUANZhao-kun StatekeylaboratoryofEnvironmentalAquaticChemistry ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China ChangshaVocationalSchoolofEnvironmentalTechnology Changsha410004China

ES-DAF, a novel DAF with low cost, high reliability and easy controllability, was studied. Without a costly air saturator, ES-DAF consists of an ejector and a static mixer between the pressure side and suction side of the recycle rotary pump. The bubble size distribution in this novel unit was studied in detail by using a newly developed CCD imagination through a microscope. Compared with m-DAF under the same saturation pressure, ES-DAF can produce smaller bubble size and higher bubble volume concentration, especially in lower pressure. In addition, the bubble size decreases with the increase of reflux ratio or decrease of superficial air-water ratio. These results suggested that smaller bubbles will be formed when the initial number of nucleation sites increases by enhancing the turbulence intensity in the saturation system.

关键词： dissolved air flotation(DAF) bubble size distribution air saturation system CCD imagination

Earthquake damage potential and critical scour depth of bridges exposed to flood and seismic hazards under lateral seismic loads

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 579-594页

作者： Shin-tai Song Chun-Yao Wang Wen-Hsiu Huang Department of Civil Engineering Chung-Hsing University Structural Design Department Giant Home Engineering and Consultant

many bridges located in seismic hazard regions suffer from serious foundation exposure caused by riverbed scour. Loss of surrounding soil significantly reduces the lateral strength of pile foundations. When the scour depth exceeds a critical level, the strength of the foundation is insufficient to withstand the imposed seismic demand, which induces the potential for unacceptable damage to the piles during an earthquake. This paper presents an analytical approach to assess the earthquake damage potential of bridges with foundation exposure and identify the critical scour depth that causes the seismic performance of a bridge to differ from the original design. The approach employs the well-accepted response spectrum analysis method to determine the maximum seismic response of a bridge. The damage potential of a bridge is assessed by comparing the imposed seismic demand with the strengths of the column and the foundation. The versatility of the analytical approach is illustrated with a numerical example and verified by the nonlinear finite element analysis. The analytical approach is also demonstrated to successfully determine the critical scour depth. Results highlight that relatively shallow scour depths can cause foundation damage during an earthquake, even for bridges designed to provide satisfactory seismic performance.

关键词： soil-structure interaction seismic analysis bridge pile foundation scour

Synthesis, Post-modification and Catalytic Properties of metal-organic Framework NH2-mIL-53（Al）

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Chemical Research in Chinese Universities 2017年第2期33卷 231-238页

作者： LIU Lili tai Xishi ZHOU Xiaojing LIU Lijuan School of Chemistry & Chemical Engineering and Environmental Engineering Weifang University Weifang 261061 P. R. China

A postsynthetic modification method was used to prepare salicylaldehyde functionalized metal-organicframeworks through the nucleophilic addition of salicylaldehyde with the amine group present in the frameworks ofNH2-mIL-53（A1）. Hydroxyl groups were successfully grafted onto NI-I2-mIL-53（A1）, and imine groups were ***, these hydroxyl and imine groups of the resulting NH2-mIL-53（A1）-SA can be used as the anchoringgroup to stabilise Au^3＋ ions and Au^0 nanoparticles（NPs）. By doing this, Au^3＋ ions and Au^0 NPs were successfully en-capsulated in the cages of NH2-mIL-53（A1） by a simple impregnation method. The resulting gold functionalizedNH2-mIL-53（AI） showed good catalytic activities in the one-pot synthesis of structurally divergent propargylaminesby three-component coupling reactions of aldehydes, amines and alkynes. Various aromatic/aliphatic aldehydes, aro-matic alkynes, and piperidine were able to undergo three-component coupling on NH2-mIL-53（A1）-Au. In addition,the catalyst NH2-m/L-53（A/）-Au was recovered easily by centrifugation and reused up to four times. Thus, it can beused for the environmentally friendly synthesis ofpropargylamines.

关键词： metal-organic framework Postmodification NH2-mIL-53(AI) Three-component coupling Propargyl-amine

Optimization of shale gas reservoir evaluation and assessment of shale gas resources in the Oriente Basin in Ecuador

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Petroleum Science 2018年第4期15卷 756-771页

作者： Hong Zhang Jun-tai Shi Xiang-Fang Li School of Petroleum Engineering Key Laboratory of Petroleum Engineering of the Ministry of EducationChina University of PetroleumBeijing

The petroleum geological features of hydrocarbon source rocks in the Oriente Basin in Ecuador are studied in detail to determine the potential of shale gas resources in the basin. The favorable shale gas layer in the vertical direction is optimized by combining logging identification and comprehensive geological analysis. The thickness in this layer is obtained by logging interpretation in the basin. The favorable shale gas accumulation area is selected by referring to thickness and depth data. Furthermore, the shale gas resource amount of the layer in the favorable area is calculated using the analogy method. Results show that among the five potential hydrocarbon source rocks, the lower Napo Formation is the most likely shale gas layer. The west and northwest zones, which are in the deep-sea slope and shelf sedimentary environments, respectively, are the favorable areas for shale gas accumulation. The favorable sedimentary environment formed thick black shale that is rich in organic matter. The black shale generated hydrocarbon, which migrated laterally to the eastern shallow water shelf to form numerous oil fields. The result of the shale gas resource in the two favorable areas,as calculated by the analogy method, is 55,500×10;m;. This finding shows the high exploration and development potential of shale gas in the basin.

关键词： Ecuador Oriente Basin Shale gas Optimization Analogy method Amount of resources

Inhibitory Effect of Isoflavones on Prostate Cancer Cells and PTEN Gene

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Biomedical and Environmental Sciences 2006年第1期19卷 35-41页

作者： FENG CAO tai-YI JIN YUAN-FEN ZHOU Department of Occupational Health and Toxicology School of Public Health Fudan University Shanghai 200032 China

Objective To explore the mechanisms by which genistein and daidzein inhibit the growth of prostate cancer cells. methods LNCaP and PC-3 cells were exposed to genistein and daldzein and cell viability was determined by mTF assay and cytotoxicity of the drugs by LDH test. Flow cytometry （FCm） was used to assess the cell cycle in LNCaP and PC-3 cells. Reverse transcription-polymerase chain reaction （RT-PCR） was applied to examine the expression of PTEN gene （a tumor suppressor gene）, estrogen receptor alpha gene （ERα）, estrogen receptor beta gene （ERβ）, androgen receptor gene （AR） and vascular endothelial growth factor gene （VEGF）. Results The viability of PC-3 and LNCaP cells decreased with increasing concentrations and exposure time of genistein and daidzein. Genistein increased G2/m phase cells in PC 3 cells while decreased S phase cells in LNCaP cells in a dose-dependent manner. Daidzein exerted no influence on the cell cycle of LNCaP and PC-3 cells, but the apoptosis percentage of LNCaP cells was elevated significantly by daidzein, Genistein induced the expression of PTEN gene in PC-3 and LNCaP cells. Daidzein induced the expression of PTEN gene in LNCaP but not in PC-3 cells. The expression of VEGF, ERα and ERβ genes decreased and AR gene was not expressed after incubation with genistein and daldzein in PC-3 cells. In LNCaP cells, the expression of VEGF and AR gene decreased but there was no change in the expression of ERα and ERβ gene after incubation with genistein and daidzein. Conclusion Genistein and daidzein exert a timeand dose-dependent inhibitory effect on PC-3 and LNCaP cells. The down-regulation of ER gene by daidzein influences the growth of PC-3 ceils directly, The inhibition of PC-3 cells by genistein and that of LNCaP cells by genistein and daidzein may be via Alct pathway that is repressed by PTEN gene, which subsequently down-regulates the expression of AR and VEGF genes. Our results suggest that the expression of PTEN gene plays a key role and s

关键词： Isoflavones Genistein Daidzein PC-3 LNCaP PTEN ERα ERβ VEGF

Source process of the 2010 Yushu,Qinghai,earthquake

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Science China Earth Sciences 2010年第9期53卷 1249-1251页

作者： Yong Zhang LiSheng Xu Yun-tai Chen Institute of Geophysics China Earthquake Administration Beijing 100081 China

The comprehensive waveform analysis of the Love waves and P waves shows that the Yushu m S7.1 (m W6.9) earthquake consists of two distinct sub-events. The first one occurred in the first 5 s releasing less seismic moment, and the second occurred in the later 11 s releasing more seismic moment. Spatially, the first sub-event surrounded the hypocenter, and the second, about 30 km away from the first, was much closer to the Yushu city and broke through the ground surface. In terms of the rupture velocity to which the peak values of the two sub-events correspond, the first sub-event propagated with an average rupture velocity of 1.6 km/s, however, the second propagated with an average rupture velocity of 4.0 km/s which is actually superior to the shear-wave velocity in the hypocentral region. The magnitude of the Yushu earthquake is in the lower margin of large earthquakes. The results obtained in this study indicate that the super-shear rupture possibly appears in earthquakes with magnitude of around 7.0, instead of only in the great earthquakes with magnitude around 8.0 [14, 15]. In addition, the energy focusing caused by the super-shear rupture should take key responsibility for the tremendous damage to the Yushu city as well as the ground-surface breakage related to the larger second sub-event.

关键词： Velocity Wave propagation