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Chinese Chemical Letters 2011年第9期22卷 1111-1114页

作者： Xiao dong li Mao sheng Zhan Kai Wang School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N（1,7）-n-OPIMB and N（1,7）-n-SP1MB （n = 20, 22）, respectively, were synthesized. The mesomorphic properties were investigated by differential scanning calorimetry （DSC）, polarizing optical microscopy （POM） and X-ray diffraction （XRD）. Compared to the direct transition from the isotropic phase to the chiral B4 phase examined in N（1,7）-n-OPIMB, N（1,7）-n-SPIMB exhibited a rare Iso-Ncol-Colh-B4 phase sequence. The combination of the asymmetric low bent-angle 1,7-naphathalene central core and the flexible long alkylthio tail is considered to play an important role in the formation of such a novel phase sequence.

关键词： Bent-shaped liquid crystal Alkylthio tail Mesomorphic behaviour

Stable isotopes of water as a tracer for revealing spatial and temporal characteristics of groundwater recharge surrounding Qinghai Lake,China

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Journal of Mountain Science 2022年第9期19卷 2611-2621页

作者： li dong-sheng CUI Bu-li ZHAO Yun-duo ZUO Feng-lin State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China School of Ocean and Earth Science Tongji UniversityShanghai 200092China School of Resources and Environmental Engineering Ludong UniversityYantai 264025China School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Advanced Interdisciplinary Institute of Environment and Ecology Beijing Normal UniversityZhuhai 519087China

Studying spatial and temporal characteristics of regional groundwater recharge will guide the scientific management and sustainable development of regional water *** study investigated stable isotopes(δ^(18)O and δ^(2) H)of precipitation,groundwater,river water and lake water during 2019-2020 in Qinghai Lake Basin to reveal the spatial and temporal characteristics of groundwater *** local meteoric water line was simulated using ordinary least squares regression(δ^(2) H=7.80δ^(18)O+10.60).The local evaporation lines of the river water,lake water and groundwater were simulated asδ^(2) H=6.21δ^(18)O-0.72,δ^(2) H=5.73δ0-3.60 and δ^(2) H=6.59δ0+1.76,*** δ^(2) H and δ^(18)O of river water and groundwater were in more depleted values due to the recharge by precipitation at high altitudes or precipitation effects,and theδ^(2) H andδ^(18)O of the lake water were in more enriched values because of *** relationship between the δ^(2) H and δ^(18)O of groundwater and river water was not significantly different,indicating a strong hydrological connection between the groundwater and river water surrounding Qinghai ***,the maximum values of δ^(18)O and the minimum values of lc-excess of groundwater in most regions were both in August,and the minimum values of δ^(18)O and the maximum values of lc-excess of groundwater in most regions were both in ***,the groundwater was recharged by soil water with strong evaporation in August and recharged by precipitation at high altitudes in *** recharge rate of groundwater was relatively fast in areas with large slopes and large hydraulic gradients(e.g.,south of Qinghai Lake),and in areas with strong hydrological connections between the groundwater and river water(e.g.,the Buha River Valley).Those results can provide data support for protection and utilization of water resources in Qinghai Lake Basin,and provide reference for groundwater research in closed lake basi

关键词： Recharge of groundwater Hydrogen and oxygen stable isotopes line-conditioned excess Surface water and groundwater Qinghai Lake Basin

Effects on the pouch of different digestive tract reconstruction modes assessed by radionuclide scintigraphy

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World Journal of Gastroenterology 2010年第11期16卷 1402-1408页

作者： li, dong-sheng Xu, Hui-Mian Han, Chun-Qi li, Ya-Ming China Med Univ Affiliated Hosp 1 Dept Oncol Shenyang 110001 Liaoning Prov Peoples R China

AIM: To determine the effect of three digestive tract reconstruction procedures on pouch function, after radical surgery undertaken because of gastric cancer, as assessed by radionuclide dynamic imaging. METHODS: As a measure of the reservoir function, with a designed diet containing technetium-99m (99mTc), the emptying time of the gastric substitute was evaluated using a 99mTc-labeled solid test meal. Immediately after the meal, the patient was placed in front of a γ camera in a supine position and the radioactivity was measured over the whole abdomen every minute. A frame image was obtained. The emptying sequences were recorded by the microprocessor and then stored on a computer disk. According to a computer processing system, the half-emptying actual curve and the fitting curve of food containing isotope in the detected region were depicted, and the half-emptying actual curves of the three reconstruction procedures were directly compared. RESULTS: Of the three reconstruction procedures, the half-emptying time of food containing isotope in the Dual Braun type esophagojejunal anastomosis procedure (51.86±6.43 min) was far closer to normal, signif icantly better than that of the proximal gastrectomy orthotopic reconstruction (30.07±15.77 min, P=0.002) and P type esophagojejunal anastomosis (27.88±6.07 min, P=0.001) methods. The half-emptying actual curve and f itting curves for the Dual Braun type esophagojejunal anastomosis were fairly similar while those of the proximal gastrectomy orthotopic reconstruction and P type esophagojejunal anastomosis were obviously separated, which indicated bad food conservation in the reconstructed pouches. CONCLUSION: Dual Braun type esophagojejunal anastomosis is the most useful of the three procedures for improving food accommodation in patients with a pouch and can retard evacuation of solid food from the reconstructed pouch.

关键词： Isotope γ-scintigraphy T1/2 time Digestive tract reconstruction 99mTc-DTPA Emptying time

Stable isotopes and chloride ion of precipitation events in the northeastern Tibetan Plateau, China

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Journal of Mountain Science 2021年第4期18卷 834-846页

作者： CUI Bu-li li dong-sheng JIANG Bao-fu WANG Ying WANG Ya-xuan WANG Long-sheng li Xiao-yan State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China School of Resources and Environmental Engineering Ludong UniversityYantai 264025China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China

Stable isotopes and chloride ion of precipitation are ideal environmental tracers to explain and reveal the formation and evolution mechanisms of water bodies. It is crucial to investigate the stable isotopes and chloride in precipitation events in the northeastern part of the Tibetan Plateau(NETP) due to the limitation of available data. This study sampled each event of precipitation during the period from July 2018 to June 2019 and the monthly dustfall in the NETP to investigate the temporal changes of stable isotopes and chloride in precipitation, and to reveal the moisture source of precipitation over the NETP using a back trajectory model. Results showed that the δ^(2)H values of precipitation ranged from-183.51‰ to 17.75‰, and the δ^(18)O values ranged from-25.18‰ to 0.48‰. The slope of the Local Meteoric Water line was slightly lower than 8 due to the effect of belowcloud secondary evaporation on the precipitation process. Most d-excess values were higher than 10‰ because moisture recycled from the continent and Qinghai Lake surface mixed with precipitation. The chloride in precipitation accounted for 86.5% of the annual total deposition mass of chloride(1329.64 mg/m2), indicating that precipitation was the main source of chloride in the NETP. The temperature and amount effects of stable isotope in the precipitation were obvious in the NETP. The precipitation was predominantly derived from the Westerly Circulation from September through May and the East Asian Monsoon from June to August, with precipitation amounts of 246.5 mm and 178.0 mm, respectively, indicating that the precipitation over the NETP brought by the Westerly Circulation was more than that brought by the East Asian Monsoon. The air mass over the NETP transited in late May and early September, and a slight change in transition period would mainly be related to the intensity of the East Asian Monsoon, which is strongly influenced by El Ni?o-Southern Oscillation. These results provide not only bas

关键词： Stable isotope Chloride ion Precipitation Moisture source Northeastern Tibetan Plateau

Glacier extent changes and possible causes in the Hala Lake Basin of Qinghai-Tibet Plateau

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Journal of Mountain Science 2019年第7期16卷 1571-1583页

作者： li dong-sheng CUI Bu-li WANG Ying XIAO Bei JIANG Bao-Fu School of Resources and Environmental Engineering Ludong UniversityYantai 264025China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Glacier is a common sensitivity indicator of environmental and global climate *** the relationship between glacier area and climate change will help reveal glacier change mechanisms and future *** changes are also of great significance to the regulation of regional water *** study selected the Hala Lake Basin in the northeastern Qinhai-Tibet Plateau as a study area,and examined the relationships between the temporal and spatial change of glaciers in the northeastern Qinghai-Tibet Plateau and climate change based on remote sensing imagery,climatological data,and topographic data during the past 30 *** showed that glacier area in the Hala Lake basin fluctuated and decreased from106.24 km2 in 1986 to 78.84 km2 in 2015,with a decreasing rate of 0.94 km2·*** number of glacier patches,mean patch area,and largest patch index all decreased from 1986 to 2015,while the splitting index increased from 1986 to 2015,indicating that the landscape fragmentation of glacier in the Hala Lake Basin was increasing significantly during the study *** area change was mainly concentrated in the slopes>25°with an altitude of 4500-5000 m,and the retreating rate of glacier of sunny slope was obviously higher than that of shady *** center of glacier in the basin moved from southwest to northeast towards high *** of the response of glacier extent to climate change showed that temperature was the dominant factor affecting glacier area dynamic change in the Hala Lake *** is predicted that in future several years,the glacier area will decrease and fragment continually as a result of global warming on the Tibetan Plateau.

关键词： Glacier extent Climate change Hala Lake Basin Qinghai-Tibet Plateau

linearity optimization of edge filter demodulators in FBG_s

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Optoelectronics Letters 2008年第3期4卷 193-195页

作者： li dong-sheng SUI Qing-mei CAO Yu-qiang Optical Fiber Sensor Technology and Engineering Research Center Shandong University Jinan 250061 China

A kind of electric circuit is improved to optimize the linearity of edge filter demodulators in FBG .By using a logarithm amplifier and an extraction operation, the linear range of optimized edge filter demodulators has been broadened effectively, and the requirement of optical filter＇s linear range has been reduced. Theoretical analyses and the simulation results indi-cated that the linear range of optimized edge fdter demodulator＇s covers the whole transition region of the edge filter, while a strict linearity of the optical filter is not necessary.

关键词：光纤解调器线性分析分析方法

Wear Behavior and Mechanism of Spheroidal Graphite Cast Iron

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Journal of Iron and Steel Research International 2013年第10期20卷 81-86页

作者： YANG Zi-run li dong-sheng WANG Lan WANG Shu-qi WEI Min-xian School of Materials Engineering Yancheng Institute of Technology School of Materials Science and Engineering Jiangsu University

Wear behavior and mechanism of spheroidal graphite cast iron were studied on a pin on-disk elevated tem- perature wear tester. The phase and morphology of worn surfaces were examined by X ray diffraction and scanning electron microscopy. Results show that with an increase of load, wear rate of spheroidal graphite cast iron gradually increases under low loads, rapidly increases or potentially increases under high loads; wear rate increases with in- creasing ambient temperature. At 25 200 ℃, adhesive wear prevails; oxidative wear and adhesive wear coexist at 400 ℃. As load surpasses 150 N at 400 ℃, extrusive wear appears. The elevated-temperature wear of spheroidal graphite cast iron is a physical and chemical process including the following reactions： xFe＋y/2O2-FexOy , 2C＋ O2- 2CO and Fex Oy ＋yCO-xFe＋yCO2. Hence, at 400 ℃, the amount of graphite and tribo oxides are substan- tially reduced because of reductive function of graphite. It can be suggested that wear reduced effect of graphite and tribo-oxides is impaired.

关键词： spheroidal graphite cast iron wear behavior wear mechanism tribo oxide microstructure

Effects of SO_2 and SO_3 on the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans by de novo synthesis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 363-369页

作者： Ke SHAO Jian-hua YAN Xiao-dong li sheng-yong LU Mu-xing FU Ying-lei WEI State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

The effects of SO2,SO3 on de novo synthesis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were studied using model fly ashes incorporating copper oxide and activated carbon. It was found that the inhibitive effect of SO2 on PCDD/Fs formation is similar to that of SO3. To investigate the inhibition mechanism,CuSO4 formations from both CuO and CuCl2 were examined. The ability of SO3 to convert CuCl2 and CuO on a silica support into sulfate is much stronger than that of SO2. However,replacing silica by activated carbon leads to a much high conversion of CuCl2 to CuSO4 in the presence of SO2. The promotion by activated carbon is explained by the reduction of CuCl2 to Cu2Cl2 and the eventual conversion of Cu2Cl2 into CuSO4 is the main inhibition mechanism of SO2 on de novo synthesis of PCDD/Fs.

关键词： Cuprous chloride Model fly ash Sulfation Cupric chloride

High-Temperature Oxidation Resistance of Austenitic Stainless Steel Cr18Ni11Cu3Al3MnNb

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Journal of Iron and Steel Research International 2012年第5期19卷 74-78页

作者： li dong-sheng DAI Qi-xun CHENG Xiao-nong WANG Rong-rong HUANG Yan School of Material Science and Engineering Jiangsu UniversityZhenjiang212013JiangsuChina

The kinetic curve of the high-temperature oxidation of austenitie stainless steel Crl8Ni11 Cu3Al3MnNb at different temperatures was measured by weighting method. It is showed that the oxidation curves at 700 and 800 ℃ followed the parabolic law, and the steel presented an excellent anti-oxidation. The surface morphology and structure of the oxide film were studied by scanning electron microscopy and X-ray diffraction methods. A dense oxide film was attained at 700 and 800 ℃, mainly composed of the hexagonal Al2 O3, Fe2 O3, and a small amount oxide of Cr at 700 ℃. At 900 ℃ the oxide film started to delaminate, and was composed of （Cr,Fe）2O3 and the spinel CuCrMnO4 and Fe（Cr, Al） 2O3.

关键词： austenitic stainless steel high-temperature oxidation oxidation scale cyclic oxidation spinel

Marker-assisted selection to pyramid Fusarium head blight resistance loci Fhb1 and Fhb2 in the high-quality soft wheat cultivar Yangmai 15

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Journal of Integrative Agriculture 2023年第2期22卷 360-370页

作者： HU Wen-jing FU Lu-ping GAO De-rong li dong-sheng liAO Sen LU Cheng-bin Key Laboratory of Wheat Biology and Genetic Improvement for Low&Middle Yangtze Valley Ministry of Agriculture and Rural AffairsLixiahe Institute of Agricultural SciencesYangzhou 225007P.R.China College of Agronomy&Center for Crop Genome Engineering Henan Agricultural UniversityZhengzhou 45002P.R.China Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Agricultural College Yangzhou UniversityYangzhou 225009P.R.China Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009P.R.China College of Agriculture Yangtze UniversityJingzhou 434023P.R.China

Fusarium head blight(FHB)is one of the most detrimental wheat diseases which greatly decreases the yield and grain quality,especially in the middle and lower reaches of the Yangtze River of ***1 and Fhb2 are two major resistance loci against Fusarium *** 15(YM15)is one of the most popular varieties in the middle and lower reaches of the Yangtze River,and it has good weak gluten characters but poor resistance to *** we used Fhb1 and Fhb2 to improve the FHB resistance of YM15 by a molecular marker-assisted selection(MAS)backcrossing *** selection of agronomic traits was performed for each *** successfully selected seven introgressed lines which carry homozygous Fhb1 and Fhb2 with significantly higher FHB resistance than the recurrent parent *** of the introgressed lines had agronomic and quality characters that were similar to *** study demonstrates that the pyramiding of Fhb1 and Fhb2 could significantly improve the FHB resistance in wheat using the MAS approach.

关键词： Fusarium head blight marker-assisted selection Fhb1 Fhb2 resistance breeding wheat