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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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Science China Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. Resources and Environmental School, {3. university, {3. 73.000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of {3., {3. 73.000, China 3. College of Resources Science & technology, Beijing Normal university, Beijing 100875, China Resources and Environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources Science & technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Theory of truth degrees of propositions in the logic system Ln^＊

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Science in China(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2.& WANG Guojun1,3.1. Institute of Mathematics, Shaanxi Normal university, Xi’an 710062. China 2. School of sciences,{2.,{3., China 3. Research Center for Science, Xi’an Jiaotong university, Xi’an 710049, China Institute of Mathematics Shaanxi Normal University Xi’an China School of sciences Lanzhou University of Technology Lanzhou China Research Center for Science Xi’an Jiaotong University Xi’an China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

复方碘口腔喷雾原位膜的制备及促口腔溃疡修复评价

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中国药科大学学报 2024年

作者：张小军黄山芩郭潇涵季梦菲沈雁陈大全许颖 1.江苏大学药学院 2.中国药科大学药学院 3.烟台大学药学院江苏大学药学院中国药科大学药学院烟台大学药学院

采用原位凝胶技术，制备了新型复方碘口腔喷雾原位膜，用于发挥缓释作用，并促进口腔溃疡创面修复。首先以喷雾状态和成膜时间为指标，对喷雾药液的处方和工艺进行优化。以成膜时间和药膜黏附性为评价指标对药液混合比例进行考察。并对... 详细信息

采用原位凝胶技术，制备了新型复方碘口腔喷雾原位膜，用于发挥缓释作用，并促进口腔溃疡创面修复。首先以喷雾状态和成膜时间为指标，对喷雾药液的处方和工艺进行优化。以成膜时间和药膜黏附性为评价指标对药液混合比例进行考察。并对最优处方制备的复方碘口腔喷雾药液的药物含量、稳定性、pH、喷雾效果，及原位膜的成膜时间、溶解性、吸湿性、保湿性、体外释放等理化性质进行考察；此外，通过细胞实验考察了成膜材料的生物相容性及复方碘口腔喷雾原位膜的促迁移效果；采用兔口腔溃疡模型，对复方碘口腔喷雾在体成膜效果及促修复效果进行评价。实验结果显示，最优处方制备的药液A和药液B的pH分别为6.2. ± 0.02. 6.42.± 0.03.符合正常口腔黏膜pH范围；稳定性好，具有良好的喷雾状态；药液B中碘含量为（1.96 ± 0.01）mg/mL；原位膜体外成膜时间为（118.3.± 3.6）s，口腔内成膜时间为（13..3.± 4.6）s；2. h溶解率为（87.3. ± 1.74）%，吸湿率为（12..17 ± 7.13.%，保湿率为（2..85 ± 2.50）%；复方碘口腔喷雾原位膜中碘含量为（47.42.± 0.3.）mg/g；具有良好的柔韧性和黏附性，并具有一定的缓释效果。细胞实验中，原位膜表现出良好的促成纤维细胞迁移作用。兔口腔溃疡实验表明，复方碘口腔喷雾在体可快速成膜，并可显著促进口腔溃疡修复。本研究所开发的复方碘口腔喷雾原位膜，制备工艺稳定，并可有效促进口腔溃疡创面修复，为口腔黏膜制剂的研究和开发提供了新思路，并具有良好的转化前景。

关键词：口腔喷雾原位膜复方碘口腔溃疡缓释促修复

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science China Earth sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2., WU Qingbai2.& WANG Yibo3.1. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, China 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of sciences, {2. 73.000, China 3. Resource and Environment School, {2. university, {2. 73.000, China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 2..11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric sciences, {3. {2., {3. 73.000, China 2. LASG, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., China) College of Atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Acad. of Sci. Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Impact of land-use change on hydrological processes in the Maying River basin, China

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Science China Earth sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3. ZHANG Yu2. LIU Guimin2.& CHEN Lin3.1. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, China 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of sciences, {2. 73.000, China 3. Resource and Environment School, {2. university, {2. 73.000, China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of China. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest China, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 2..12., a base flow decline of 3..3.0}, a drop in the maximum peak discharge of 3..77%, and mean discharge decreases in spring and autumn of 3..05% and 2..87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73.-81%, and that to the influence of base flow reaching 62.-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2. TANG Jun 2., ZHANG AiHua 3.& JIA Ya 2.1 Department of Physics,{3., lanzhou 73.050, China 2.Department of Physics, Central China Normal {2., Wuhan 43.079, China 3.College of Electrical and Information Engineering,{3., lanzhou 73.050, China Department of Physics Lanzhou University of Technology Lanzhou China Department of Physics Central China Normal University Wuhan China College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science China Earth sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2. AN Lizhe1, 3. WU Guangjian2. XU Baiqing2. MA Xiaojun 3. LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of {3., lanzhou 73.000, China 2. Institute of Tibetan Plateau Research, Chinese Academy of {3., Beijing 100085, China 3. College of Life Science, lanzhou university, lanzhou 73.000, China Chinese Academy of sciences lanzhou university

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 2..4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science China(Technological sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2., LIU Weimin 2.& LIANG Yongmin 2.1. School of Chemical Engineering and {3., China university of Mining and {3., Xuzhou 2.1008, China 2. State Key Laboratory of Solid Lubrication, {3. Institute of Chemical Physics, Chinese Academy of sciences, {3. 73.000, China School of Chemical Engineering and technology China University of Mining and Technology Xuzhou China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3.(PO 4 ) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.