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Effects of the Spatial Coupling of Water and Fertilizer on the Chlorophyll Fluorescence Parameters of Winter Wheat Leaves

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Agricultural Sciences in China 2011年第12期10卷 1923-1931页

作者： shen yu-fang li shi-qing State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau/Northwest A＆F University Yangling 712100 P.R.China

Wheat is an important agricultural crop in the Loess region of China, where there is drought stress and low availability of soil nitrogen and phosphorus. Using a pulse modulation fluorometer, we studied the effects of water, nitrogen, and phosphorus on the kinetic parameters of chlorophyll fluorescence in winter wheat. The wheat was grown in layered columns of Eum-Orthic Anthrosol （Cinnamon soil）, with the water content and nutrient composition of each layer controlled. The results showed that the kinetic parameters of chlorophyll fluorescence were sensitive to water stress. The basic fluorescence （F0） of leaves was higher in the dry treatment （0-30 cm layer at 40-45% of field capacity, 30-90 cm at 75-80% of field capacity） compared to the wet treatment （entire soil column at 75-80% of field capacity）. The maximal fluorescence （Fm）, the variable fluorescence （Fv）, the photochemical efficiency （Fv/Fm） and potential activites （Fv/F0） of photosystem 2 （PS2） were significantly lower in the dry treatment. Although drought stress impaired PS2 function, this effect was significantly ameliorated by applying P or NP fertilizer, but not N alone. P application increased FJFm, both in well-watered and water stressed plants, especially when fertilizer was applied throughout the column or within the top 30 em of soil. A combined fertilizer improved photosynthesis in well watered plants, with Fm and F,fFm being the highest when fertilizer was applied throughout the columns. For drought stressed, plants FJFm was significantly greater when combined fertilizer was added within the top 30 cm of soil. We concluded that, when growing winter wheat in both arid and semi-arid parts of the Loess region of China, it is important to guarantee the nutrient supply in the top 30 cm of the soil.

关键词： water stress nutrient spatial coupling chlorophyll fluorescence column experiment

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Effects of plastic film mulching on soil greenhouse gases(CO2,CH4 and N2O) concentration within soil profiles in maize fields on the Loess Plateau,China

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Journal of Integrative Agriculture 2016年第2期15卷 451-464页

作者： NAN Wei-ge yuE Shan-chao HUANG Hai-zhou li shi-qing shen yu-fang State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 P.R. China Institute of Soil and Water Conservation Northwest A&F University Yangling 712100 P.R. China University of Chinese Academy of Sciences Beijing 100049 P.R. China

To better understand the effects of plastic film mulching on soil greenhouse gases（GHGs） emissions,we compared seasonal and vertical variations of GHG concentrations at seven soil depths in maize（Zea mays L.） fields at Changwu station in Shaanxi,a semi-humid region,between 2012 and *** samples were taken simultaneously every one week from non-mulched（BP） and plastic film-mulched（FM） field *** results showed that the concentration of GHGs varied distinctly at the soil-atmosphere interface and in the soil profile during the maize growing season（MS）.Both carbon dioxide（CO_2） and nitrous oxide（N_2O） concentrations increased with increasement of soil depth,while the methane（CH_4）concentrations decreased with increasement of soil depth.A strong seasonal variation pattern was found for CO_2 and N_2O concentrations,as compared to an inconspicuous seasonal variation of CH_4 *** mean CO_2 and N_2O concentrations were higher,but the mean CH_4 concentration in the soil profiles was lower in the FM plots than in the BP *** results of this study suggested that plastic film mulching significantly increased the potential emissions of CO_2and N_2O from the soil,and promoted CH_4 absorption by the soil,particularly during the MS.

关键词： greenhouse gas soil profile plastic film mulching growing season

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Design and FPGA implementation of multi-wing chaotic switched systems based on a quadratic transformation

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Chinese Physics B 2021年第2期30卷 240-249页

作者： qing-yu shi Xia Huang fang yuan yu-Xia li College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

Based on a quadratic transformation and a switching function,a novel multi-wing chaotic switched system is ***,a 4-wing chaotic system is constructed from a 2-wing chaotic system on the basis of a quadratic ***,a switching function is designed and by adjusting the switching function,the number and the distribution of the saddle-focus equilibrium points of the switched system can be ***,a set of chaotic switched systems,which can produce 6-to-8-12-16-wing attractors,are *** Lyapunov exponent spectra,bifurcation diagrams,and Poincarémaps are given to verify the existence of the chaotic ***,the digital circuit of the multi-wing chaotic switched system is designed by using the Verilog HDL fixed-point algorithm and the state machine ***,the multi-wing chaotic attractors are demonstrated via FPGA *** experimental results show that the number of the wings of the chaotic attractors can be expanded more effectively with the combination of the quadratic transformation and the switching function methods.

关键词： quadratic transformation chaotic switched system FPGA

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Robust tantalum tuned perovskite oxygen electrode for reversible protonic ceramic electrochemical cells

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Rare Metals 2024年第7期43卷 3055-3065页

作者： yu-shi Feng yu shen fang Wang Chuan Tian Qin-Yi Hu Qian Duan Jing-Wei li Di Bao School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China Zhongshan Institute of Changchun University of Science and Technology Zhongshan528437China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022China Key Laboratory of Preparation and Applications of Environmental Friendly Materials Ministry of EducationJilin Normal UniversityChangchun 130103China

Perovskite oxides with diverse composition and structure have exhibited grand advances in boosting the oxygen reduction and evolution reaction(ORR/OER),which are essential for the reversible protonic ceramic electrochemical cell(R-PCEC)toward the sustainable hydrogen production and ***,enhancement of their activity and stability remains ***,we develop the Ta-regulated BaCo_(0.7)Fe_(0.3)O_(3-δ)perovskite oxygen electrode(Ba(Co_(0.7)Fe_(0.3))_(1-x)Ta_xO_(3-δ))with abundant oxygen defects and achieve the simultaneous enhancement in the electrocatalytic activity and stability toward ORR and ***-fabricated R-PCEC with(Ba(Co_(0.7)Fe_(0.3))_(0.9)Ta_(0.1)O_(3-δ))(BCFT10)oxygen electrode performs high power density of 1.47 W·cm^(-2)at 650℃in fuel cell mode,and the current density is up to-2.11 A·cm^(-2)at 1.4 V at 650℃in electrolysis mode,as well as the good stability in both the fuel cell and electrolysis ***,the cell also demonstrates a stable cycling operation between fuel cell and electrolysis mode,suggesting a great potential of BCFT10 as oxygen electrode material for R-PCECs.

关键词： Reversible protonic ceramic electrochemical cells Perovskite oxide Oxygen electrode Ta element doping Oxygen defects

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Proteomic Analysis of the Response of liangyoupeijiu(Super High-Yield Hybrid Rice) Seedlings to Cold Stress

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Journal of Integrative Plant Biology 2006年第8期48卷 945-951页

作者： Ping-fang Yang Xiao-Juan li yu liang yu-Xiang Jing shi-Hua shen Ting-yun Kuang Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate College of the Chinese Academy of Sciences Beijing 100039 China

liangyoupeijiu is a super high-yield hybrid rice. Despite its advantages with respect to yield and grain quality, it is sensitive to cold, which keeps it from being widely cultivated. We subjected liangyoupeijiu seedlings to 4 ℃ cold treatment, then extracted the leaf proteins. After 2-D gel electrophoresis separation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, a series of differentially displayed proteins were identified. Some metabolism-associated proteins were found among the downregulated proteins, such as carbamoyl phosphate synthetase, transketolase 1, dihydrolipoamide dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase. The upregulated proteins included both stress-resistance proteins such as nucleoside diphosphate kinase I and proteins that are negative for rice growth, such as FtsH-like protein, plastid fusion and/or translocation factor （Pftf） and actin. Our results indicate that cold may inhibit liangyoupeijiu growth through decreasing metabolic activity and damaging cell structure.

关键词： cold stress Oryza sativa proteome super high-yield hybrid rice.

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Mathematical Model of Combustion in Blunt Annular Ceramic Burner

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Journal of Iron and Steel Research International 2001年第2期8卷 1-6页

作者： ZHANG Yin HE You-duo li shi-qi shen Yi-shen HUANG Xiao-yu TANG qing-hua li Heng-xu WANG Mi Baotou University of Iron and Steel Technology University of Science and Technology Beijing Anshan Iron and Steel Group Co

The computer simulation of the combustion process in blast furnace(BF) stove has been studied by using the k-ε-g turbulent diffusion flame *** combustion process in blunt annular ceramic burner was calculated by using the *** profiles of gas and air velocity,temperature of the combustion products,concentration of the components,and the shape and length of the flame during combustion have been *** with the original annular ceramic burner,the new design of the blunt one improves the mixing of the gas and the air significantly,and shortened the length of the flame.

关键词： blunt annular ceramic burner combustion turbulent diffusion flame mathematical model hot-blast stove

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Navigability of the Northern Sea Route for Arc7 ice-class vessels during winter and spring sea-ice conditions

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Advances in Climate Change Research 2022年第5期13卷 676-687页

作者： shi-Yi CHEN Stefan KERN Xin-qing li Feng-Ming HUI yu-fang YE Xiao CHENG School of Geospatial Engineering and Science Sun Yat-sen UniversityAnd Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Integrated Climate Data Center(ICDC) Center for Earth System Research and Sustainability(CEN)University of HamburgHamburg D-20144Germany

Sea ice hinders the navigability of the Arctic,especially in winter and ***,three Arc7 ice-class liquefied Natural Gas carrying vessels safely transited the Northern Sea Route(NSR)without icebreaker assistance in January *** and more Arc7 ice-class vessels are putting into the transit services in the ***,it is necessary to analyze sea-ice conditions and their impact on navigation during wintertime,and the future navigability of Arc7 ice-class vessels along the NSR during winter and *** on sea ice datasets from satellite observations and a model using data assimilation,we explored the sea-ice conditions and their impact during the first three successful commercial voyages through the NSR in *** addition,we analyzed the sea ice variation and estimated navigability for Arc7 ice-class vessels in the NSR from January to June of the years 2021–2050 using future projections of the sea-ice cover by the Coupled Model Inter-comparison Project Phase 6(CMIP6)models under two emission scenarios(SSP2-4.5 and SSP5-8.5).The results reveal lower sea ice thickness and similar sea ice concentration during these three transits relative to the past 42 years(from 1979 to 2020).We found the thickness has a larger impact on the vessels’speeds than sea ice *** likely sea ice thickness played a larger role than the sea ice concentration for the successful transit of the NSR in winter *** projections suggest sea ice thickness will decrease further in most regions of the NSR from January to June under all scenarios enabling increased navigability of the NSR for Arc7 ice-class *** vessels could transit through the NSR from January to June under all scenarios by 2050,while some areas near the coast of East Siberian Sea remain inaccessible for Arc7 ice-class vessels in spring(April and May).These findings can support the strategic planning of shipping along the NSR in winter and spring.

关键词： Northern sea route Arc7 ice-class vessel Sea ice thickness Sea ice concentration Navigability Arctic

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Mortality weighting-based method for aggregate urban air risk assessment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 702-709页

作者： qing-yu ZHANG Guo-jin SUN Wei-li TIAN yu-mei WEI Si-mai fang Jin-feng RUAN Guo-rong SHAN Yao shi Department of Environmental Engineering Zhejiang University Hangzhou 310058 China Department of Chemical Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control Hangzhou 311202 China College of Information University of International Business and Economic Beijing 100029 China

This paper deals with a mortality-weighted synthetic evaluation （MWSE） method for evaluating urban air risk. Sulphur dioxide （SO2）, nitrogen oxide （NOx）, and particulate matter （PMl0） were used as pollution indices. The urban area of Hangzhou, China is divided into 756 grid cells, with a resolution of 1 km× 1 km, and is evaluated using the MWSE and the air quality index （AQI）, a widely-used method to evaluate ambient air quality and air risk. In an evaluation of one day in April 2004, the surface areas categorized as levels Ⅰ and Ⅲ, as defined by the integrated air risk evaluation, were 27.3% and 3.3% lower, respectively, than grades Ⅰ and Ⅲ defined by the AQI evaluation. Meanwhile, the areas classified as level Ⅱ or above level Ⅲ by the integrated air risk evaluation were 55.1% and 101. 1% higher, respectively, than grade Ⅱ or above grade Ⅲ when using the AQI evaluation. From this comparison, we find that the MWSE method is more sensitive than the AQI method. The AQI method uses a single index to assess integrated air quality and is therefore unable to evaluate integrated air risks due to multiple pollutants. The MWSE method overcomes this problem, providing improved accuracy in air risk assessment.

关键词： Integrated air risk Mortality-weighted synthetic evaluation (MWSE) Air quality index (AQI) Air pollution

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A study of the efficacy of bacterial biofilm cleanout for gastrointestinal endoscopes

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World Journal of Gastroenterology 2010年第8期16卷 1019-1024页

作者： fang, Ying shen, Zhe li, Lan Cao, Yong Gu, li-Ying Gu, qing Zhong, Xiao-Qi yu, Chao-Hui li, You-Ming Zhejiang Univ Affiliated Hosp 1 Coll Med Dept Gastroenterol Hangzhou 310003 Zhejiang Peoples R China

AIM:To compare the influence and clearance effect of enzymatic and non-enzymatic detergents against Escherichia coli (E. coli) biofilm on the inner surface of ***:Teflon tubes were incubated in a mixture of different detergents and E. coli culture (106 CFU/mL) for 72 h at 15℃,and biofilms on the inner surface of the teflon tubes were analyzed by bacterial count and scanning electron microscopy. To evaluate the clear-ance effect of detergents,after biofilms were formed on the inner surface of Teflon tubes by 72 h lavage with E. coli culture,tubes were lavaged by enzymatic and non-enzymatic detergents at a speed of 250 mL/min,then biofilms on the inner surface were analyzed by bacterial count and scanning electron ***:Non-enzymatic detergent had a better inhi-bition function on biofilm formation than enzymatic de-tergent as it reduced bacterial burden by 2.4 log compared with the control samples (P = 0.00). Inhibition function of enzymatic detergent was not significantly different to that of control samples and reduced bac-terial burden by 0.2 log on average (P > 0.05). After lavaging at 250 mL/min for 3 min,no living bacteria were left in the tubes. Scanning electron microscopy observation showed biofi lms became very loose by the high shear force effect. CONCLUSION:Non-enzymatic detergent has a better inhibition effect on biofilm formation at room temperature. High speed pre-lavage and detergents are very important in temporal formed biofilm elimination.

关键词： Endoscopy Escherichia coli biofi lm Scanning electron microscopy Bacterial count

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Evolution of Wave Energy Deposition Profile in HT-7 Lower Hybrid Current Drive Experiment

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Chinese Physics Letters 2001年第11期18卷 1487-1489页

作者： fang yu-De shi yu-Jiang KUANG Guang-li liU yu-Xiu shen Wei-Ci DING Bo-Jiang Institute of Plasma Physics Chinese Academy of SciencesP.O.Box 1126Hefei 230031

Lower hybrid waves (LHWs) with a selected n‖ spectrum have been used to control the energy deposition profiles, and then the wave driven current profiles effectively in tokamak discharges. In our lower hybrid current drive experiment in the HT-7 tokamak, it was found that the set-up of the wave energy deposition profile is a graduation process. In the beginning phase of the wave injection duration, the waves (with different n‖ spectra)deposit almost all their energy in the central region of the plasma column, even if their n‖ are very different. Up to around one hundred milliseconds, the wave energy deposition profiles can only take their corresponding shapes according to the n‖ spectra of LHWs. It also shown that this evolution process is affected obviously by the LHW driven current profile, which has been formed early.

关键词： wave energy Lower

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