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Grain-size Age Model in Reconstructing Orbital-and Suborbital-scale Climate Changes on the Northeastern Tibetan Plateau Since the Late Glacial

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Acta Geologica Sinica(English Edition) 2020年第3期94卷 698-706页

作者： LI yuan ZHAO hui Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Western China’s Environmental Systems(MOE) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

Reconstructions of past climatic changes on the northeastern Tibetan Plateau(NETP) can provide insights into the Asian summer monsoon(ASM) variability. However, the regional climate changes on both orbital and suborbital time scales since the late Glacial remain controversial. Here we present the results of high-resolution geochemical and grain-size analyses of a sediment core from Genggahai Lake, a small, shallow lake in this area. Changes of the accumulation rate of the core sediments show a similar trend with variations of the coarse fraction. Accordingly, the chronological framework is constructed using a grain-size age model. In addition, the histories of chemical weathering and aeolian activity since the late Glacial are reconstructed based on the Al/Ti ratios and coarse fractions, respectively. The results suggest that an enhanced chemical weathering and a weakened aeolian activity occurred on the NETP under a warmer, wetter climate during the early to mid-Holocene(11.3–6.3 ka cal BP), compared with the late Glacial(17.1–11.3 ka cal BP) and the late Holocene(6.3 ka cal BP to present), which responded mainly to the strengthened ASM on orbital time scale. In addition, the synchronous occurrences of weakened chemical weathering, low lake level and intense aeolian activity on suborbital time scale reflect several episodes of weakened ASM. Furthermore, these episodes largely coincide with the centennial-to millennial-scale cold events in the North Atlantic, which demonstrates the close connection between the ASM and the cooling at high latitudes.

关键词： climate change lake sediment grain-size age model monsoon Holocene China

CrOx supported on high-silica HZSM-5 for propane dehydrogenation

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Journal of Energy Chemistry 2020年第8期29卷 225-233,I0008页

作者： zhong-Pan Hu Yansu Wang Dandan Yang zhong-Yong yuan National Institute for Advanced Materials School of Materials Science and EngineeringNankai UniversityTianjin 300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education).Nankai University Tianjin 300071China

Industrial propane dehydrogenation(PDH)catalysts generally suffer from low catalytic stability due to the coke formation onto the catalyst surface to cover the active *** exploitation of an efficient catalyst with both high catalytic selectivity and long-term stability toward PDH is of great importance but challenging to *** CrOx supported on high-silica HZSM-5 with a SiO2/Al2O3 ratio of 260(Cr/Z-5(260)is synthesized by a simple wet impregnation method,which exhibits high catalytic activity,good selectivity and excellent stability for *** a weight hourly space velocity(WHSV)of 0.59 h-1,a propylene formation rate of 4.1 mmol g-1cath-1(~32.6% propane conversion and ~94.2% propylene selectivity)can be maintained over the 5%Cr/Z-5(260)catalyst after 50 h time on stream,which is much better than commercial Cr/Al2O3(Catofin process,catalyst life is several hours)at the same reaction *** increasing the WHSV to 5.9 h-1,a high propylene formation rate of 27.9 mmol gcat-1h-1can be obtained over the 5%Cr/Z-5(260)catalyst after 50 h time on stream,demonstrating a very promising PDH *** results and Na+doping experiments reveal that the Cr species combined with Br?nsted acid sites in Cr/HZSM-5 catalysts are responsible for the high catalytic *** particular,the Br?nsted acid sites in HZSM-5 zeolite could increase the propane adsorption and enhance the C–H bond ***,the high surface area and well-defined pores of HZSM-5 zeolite can provide a special environment for the dispersion and stabilization of Cr species,thus guaranteeing high catalytic activity and stability.

关键词： Propane dehydrogenation ZSM-5 zeolite Chromium oxide Propylene BrΦnsted acid sites

Methane conversion in the presence of oxygen under low-temperature radio frequency plasma

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Journal of Natural Gas Chemistry 2010年第6期19卷 605-610页

作者： Jinhai yuan Xuejun zhong Shiyu Tan College of Chemistry and Chemical Engineering Chongqing University of Science ＆ Technology Chongqing 401331 China Chongqing Chemical Engineering Design and Research Institute Chongqing 400039 China College of Chemistry and Chemical Engineering Chongqing University Chongqing 40004 China

Methane conversion in the presence of oxygen under low-temperature radio frequency （RF） plasma was *** experiment results indicated that the following four factors,i.e.,discharge voltage,discharge area,O2/CH4 molar ratio and total gas flowrate,affected remarkably the reaction *** optimum reaction conditions of methane conversion in the presence of O2 under RF plasma are as follows：discharge voltage 1050 V,discharge area 989.1mm 2,O2/CH4 molar ratio 1/10 and total gas flowrate 200 ml/min.A methane conversion of 91% could be reached under the optimum *** is good for the breaking of C-H bonds and also acts as a sort of *** to the low-temperature plasma characteristics,the macroscopic kinetics model of methane conversion in the presence of O2 under radio frequency plasma was studied.

关键词： methane oxygen radio frequency plasma C2 hydrocarbons kinetics

Stability Analysis of Distributed Parameter Systems on Temperature Measurement of Large-scale Objects

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Journal of Thermal Science 2007年第3期16卷 248-253页

作者： Zhenliang DING Li zhong Feng yuan Department of Electronic Engineering School of Automatic Measurement and Control Harbin Institute of Technology 150001 Harbin China

In this paper, the mechanical construction, thermal regulator design and temperature measurement system of a local area were set up for large-scale linear measurement. Numerical analysis based on temperature correlated characteristic is discussed to obtain optimal observation points for the measurements. The horizontal temperature distribution of the measured area is compared with the measurement of the variation of temperature at 15℃ and 20℃ over time, and characteristic of dynamic response is also discussed. In addition, the long-time stability of measured temperature is analyzed by means of using the standard deviation. It characterizes the temperature distribution performance of a large area and how it may impact the measurement of a large-scale object.

关键词： temperature control temperature measurement distribution parameter linear measurement.

The Impact of Storm-Induced SST Cooling on Storm Size and Destructiveness: Results from Atmosphere-Ocean Coupled Simulations

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Journal of Meteorological Research 2020年第5期34卷 1068-1081页

作者： Tao GUO yuan SUN Lei LIU zhong zhong College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101

In this study, both an atmospheric model [Weather Research and Forecasting(WRF) model] and an atmosphere(WRF)–ocean(Princeton Ocean Model;POM) coupled model are used to simulate the tropical cyclone(TC) Kaemi(2006). By comparing the simulation results of the models, effects of oceanic elements, especially the TC-induced sea surface temperature(SST) cooling, on the simulated TC size and destructiveness are identified and analyzed. The results show that there are no notable differences in the simulated TC track and its intensity between the uncoupled and coupled experiments;however, there are large differences in the TC size(i.e., the radius of gale-force wind)between the two experiments, and it is the TC-induced SST cooling that decreases the TC size. The SST cooling contributes to the decrease of air–sea moisture difference(ASMD) outside the TC eyewall, which subsequently leads to the decreases in surface enthalpy flux(SEF), radial sea-level pressure gradient, absolute vorticity advection, and wind speed outside the TC eyewall. As a result, the TC size and size-dependent TC destructive potential all decrease remarkably.

关键词： tropical cyclone(TC)size destructiveness sea surface temperature(SST)cooling

Correlation of electromagnetic radiation emitted from coal or rock to supporting resistance

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Mining Science and Technology 2009年第3期19卷 317-320页

作者： JIA hui-lin WANG En-yuan SONG Xiao-yan ZHANG Hong-jie LI zhong-hui School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the *** analyzed experimental observations and field data from the Muchengjian coal mine to study the relationship between electromagnetic radiation signal intensity and stress during the fracturing of coal, or rock, and samples under *** results show that the signal intensity is positively correlated with *** addition, we investigated the change in the electromagnetic radiation intensity, the supporting resistance in a real coal mine environment, and the coal or rock stress in the mining *** data analysis indicates that:1) electromagnetic radiation intensity can accurately reflect the distribution of stress in the mining area;and, 2) there is a correlation between electromagnetic radiation intensity and supporting *** research has some practical guiding significance for rock burst forecasting and for the prevention of accidents in coal mines.

关键词： electromagnetic radiation rock burst supporting resistance coal or rock

MdWRKY15 improves resistance of apple to Botryosphaeria dothidea via the salicylic acid-mediated pathway by directly binding the MdICS1 promoter^FA

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Journal of Integrative Plant Biology 2020年第4期62卷 527-543页

作者： Xian-Yan Zhao Chen-hui Qi Han Jiang Ming-Shuang zhong Chun-Xiang You yuan-yuan Li Yu-Jin Hao State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYangling 712100China State Key Laboratory of Crop Biology MOA Key Laboratory of Horticultural Crop Biology and Germplasm InnovationShandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient ProductionCollege of Horticulture Science and EngineeringShandong Agricultural UniversityTai-An 271018China

Isochorismate synthase(ICS) plays an essential role in the accumulation of salicylic acid(SA) and plant disease resistance. Diseases caused by Botryosphaeria dothidea affect apple yields. Thus, it is important to understand the role of ICS1 in disease resistance to B. dothidea in apple. In this study, SA treatment enhanced the resistance to B. dothidea. Md ICS1 was induced by B. dothidea and enhanced the resistance to B. dothidea. Md ICS1 promoter analysis indicated that the W-box was vital for the response to B. dothidea treatment. Md WRKY15 was found to interact with the W-box using yeast one-hybrid screening. Subsequently, the interaction was confirmed by EMSA, yeast one-hybrid, Ch IP-PCR, and quantitative PCR assays. Moreover, luciferase and GUS analysis further indicated thatMd ICS1 was transcriptionally activated by Md WRKY15. Finally, we found the function of Md WRKY15 in the resistance to B. dothidea was partially dependent on Md ICS1 from the phenotype of transgenic apples and calli. In summary, we revealed that Md WRKY15 activated the transcription of Md ICS1 by directly binding to its promoter to increase the accumulation of SA and the expression of disease-related genes, thereby resulting in the enhanced resistance to *** in the SA biosynthesis pathway.

关键词： resistance thereby fir

CRYSTALLINE MORPHOLOGY IN A SERIES OF CH_(3)-SUBSTITUTED THERMOTROPIC AROMATIC POLYESTERS WITH EVEN AND ODD FLEXIBLE SPACERS

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Chinese Journal of Polymer Science 2001年第1期19卷 71-78页

作者： Shou-xi Chen zhong-ming Hu Wen-hui Song Yong-ze Jin Ren-yuan Qian State Key Laboratory of Polymer Physics and Chemistry Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080China

Crystalline morphology in a series of CH_(3)-substituted main chain thermotropic aromatic polyesters with even and odd numbered methylene spacers has been studied by polarizing optical microscopy(POM),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).On crystallization from solution evaporation spherulites of radial structure were observed in the polymers with even numbered spacers,but spherulites with concentric rings form in the polymer with odd numbered *** spherulites have a lamellar structure,which is about 10 nm in *** crystallization from nematic glassy state spherulites can not be grown;lamellar structure was only observed around disclinations in a specimen during *** the case of crystallization from nematic melt two types of spherulites can be observed far the sample with even numbered *** the sample with add numbered spacers spherulites can not be formed,but only irregular crystallites.

关键词： crystalline morphology spherulite even-odd flexible spacers CH_(3)-substituted thermotropic aromatic polyester

Hidden feature extraction for unstructured agricultural environment based on supervised kernel locally linear embedding modeling

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Advances in Manufacturing 2018年第4期6卷 409-418页

作者： zhong-Hua Miao Chen-hui Ma Zhi-yuan Gao Ming-Jun Wang Cheng-Liang Liu School of Mechatronic Engineering and Automation Shanghai University Shanghai 200072 People's Republic of China School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 People's Republic of China

An online hidden feature extraction algorithm is proposed for unknown and unstructured agricultural environments based on a supervised kernel locally linear embedding (SKLLE) algorithm. Firstly, an online obtaining method for scene training samples is given to obtain original feature data. Secondly, Bayesian estimation of the a posteriori probability of a cluster center is performed. Thirdly, nonlinear kernel mapping function construction is employed to map the original feature data to hyper-high dimensional kernel space. Fourthly, the automatic deter mination of hidden feature dimensions is performed using a local manifold learning algorithm. Then, a low-level manifold computation in hidden space is completed. Finally, long-range scene perception is realized using a 1-NN classifier. Experiments are conducted to show the effectiveness and the influence of parameter selection for the proposed algorithm. The kernel principal component analysis (KPCA), locally linear embedding (LLE), and supervised locally linear embedding (SLLE) methods are compared under the same experimental unstructured agricultural environment scene. Test results show that the proposed algorithm is more suitable for unstructured agricultural environments than other existing methods, and that the computational load is significantly reduced.

关键词： Long-range scene perception Hidden feature extraction Agricultural vehicle Unstructured agricultural environment