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Effects of Vegetation Succession on Soil Fertility Within Farming-Plantation Ecotone in Ziwuling Mountains of the Loess Plateau in China

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Agricultural Sciences in China 2010年第10期9卷 1481-1491页

作者： LIANG Jian wang Xiao-an YU Zhong-dong DONG Zhong-min wang jin-cheng School of Life Sciences Shaanxi Normal University Xi'an 710062 P.R.China College of Forestry Northwest A&F University Yangling 712100 P.R. China Department of Biology Saint Mary 's University Halifax B3H 3C3 Canada

To further understand the relationship between vegetation succession and soil fertility within farming-plantation ecotone in Ziwuling Mountains of the Loess Plateau, nine kinds of widely distributed communities at different succession stages were selected, and the effects of vegetation succession on soil fertility were studied through the methods of comparing two hierarchical clustering （similarity index： B） and other multivariate analysis. The results showed that：（i） the similarity in clustering pattern of nine communities which classified by plant species and soil nutrients respectively showed a trend of B ^-overall plant-soil0-10cn〉B^-overall plant-soil 10-20 cm 〉B^- overall plant-soil 20-40 cm, and for the top soil, it showed a trend of B^- grass-soil 0-10 cm 〉 B^-shrub-soil 0-10 cm 〉 Btree-soil0-10 cm; （ii） soil fertility increased during the succession process from abandoned land to forest community, and the soil fertility of forest community showed an increased order of coniferous forest →mixed forest →broadleaf forest; （iii） during the process of vegetation succession, the variation of topsoil fertility was higher than that of the subsurface soil （coefficient of variation： CV0-10 cm 〉CV 10-20 cm 〉 CV20-40 cm）, and when the succession developed into the stages of shrub and forest communities, the top soil fertility had been improved significantly; and （iv） for the subsurface soil of the communities at the advanced succession stages, the soil fertility also increased to some extent. Our results suggested that the method of comparing two hierarchical clustering reflected the similarity level of different cluster patterns, therefore, it was helpful to study the relationship between vegetation succession and soil fertility. There was a corresponding relationship between the change process of soil fertility from the top soil to subsurface soil and the process of vegetation succession from the early stages to the advanced stage. The differentiations of soil fertil

关键词： vegetation succession soil fertility vegetation-soil communities multivariate statistical analysis LoessPlateau

The Impact of Assimilating FY-3C GNOS GPS Radio Occultation Observations on GRAPES Forecasts

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Journal of Tropical Meteorology 2020年第4期26卷 390-401页

作者： wang jin-cheng GONG Jian-dong HAN Wei Numerical Weather Prediction Center China Meteorological AdministrationBeijing 100081 China National Meteorological Center China Meteorological AdministrationBeijing 100081 China

In the present study, a gross quality control (QC) procedure is proposed for the Global Navigation Satellite System Occultation Sounder (GNOS) Global Positioning System radio occultation (GPS RO) refractivity data to remove abnormal data before they are assimilated. It consists of a climate extreme check removing data outside the range of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) climate maxima and minima over approximately five years, and a vertical gradient check that rejects profiles containing super-refractions. These two QC steps were applied sequentially to identify outliers in GNOS GPS RO refractivity data during boreal winter 2013/*** of the abnormal refractivity profiles and the outliers at each level of the GNOS GPS RO observations were effectively removed by the proposed QC procedure. The post-QC GNOS GPS RO refractivity observations were then assimilated in the Global/Regional Analysis and PrEdiction System (GRAPES) using the three-dimensional variational(3D-Var) system. The impacts of the GNOS refractivity observation on GRAPES analysis and forecasting were evaluated and analyzed using an observation system experiment run over one whole winter season of 2013/2014. The experiment results demonstrated a positive impact of GNOS GPS RO data on analysis and forecast quality. The root mean squared error of GRAPES analysis temperature was reduced by 1%in the Southern Hemisphere (SH) extratropics and in the tropics, and the anomaly correlation scores of the forecasted 500-hPa geopotential height over the SH increased significantly during days 1 to 5. Overall, the benefits of using GNOS GPS RO data are significant in the SH and tropics.

关键词： GNOS FY-3C GPS RO Global NWP data assimilation GRAPES

Phase-field Modeling of the Influence of Elastic Field on the Nucleation and Microstructure Evolution in Precipitation

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Chinese Journal of Aeronautics 2007年第2期20卷 107-110页

作者： ZHANG Yu-xiang wang jin-cheng YANG Yu-juan YANG Gen-cang ZHOU Yao-he State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

A phase-field method was employed to study the influence of elastic field on the nucleation and microstructure evolution. Two kinds of nucleation process were considered： one using fixed nucleation probability and the other calculated from the classical nucleation theory. In the latter case, the simulated results show that the anisotropic elastic strain field yields significant effects on the behavior of nucleation. With a large lattice misfit between the matrixes and the precipitates, the nucleation process does not appear fully random but displays some spatial correlation and has a preference for the elastic soft direction. However, with a small lattice misfit, this bias does not look quite clear. On the contrary, in the case of fixed nucleation probability, the elastic field has no influence on the nucleation process. The lattice mismatch also exerts influences on the microstructure morphology： with lattice mismatch becoming larger, the microstructure proves to align along the elastic soft direction.

关键词： elastic field nucleation phase-field method precipitation

Electrochemical Probe of Hydroxylation of 4-Nitro-phenol by Cytochrome C with Hydrogen Peroxide

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Chemical Research in Chinese Universities 1998年第2期14卷 45-51页

作者： ZHU Yi-min wang jin-cheng LI jing-hong DONG Shao-jun BU Feng-quan Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022 Norma n Bethune Univer sity of Medica l Science Cha ngchun130023

BU Fengquan(Norman Bethune University of Medical Science, Changchun, 130023)(Received Dec. 2, 1996) The reaction of hydrogen peroxide with cytochrome c makes them coupled to lead to the hydroxylation of 4-nitrophenol. In situ electrochemical probe was used to detect the hydroxylation of 4-nitrophenol, which can avoid the tedious extraction procedure, the loss of the active species and the interference of some colored substances in the detection of 4-nitrocatechol by spectroscopic method. The hydroxyl radical scavengers mannitol and sodium benzoate did not eliminate hydroxylation, but the inhibitory effect of uric acid on the hydroxylation lead to the formation of the ferryl species of the protein during the reaction. These studies suggest that the electrochemical probe might efficiently detect the trace 4-nitrocatechol from the onset of the hydroxylation reaction and thus provides a more sensitive tool.

关键词： Hydrogen peroxide Hydroxylation of 4-nitrophenol Cytochrome c

Synthesis and Bioactivities of Novel N-（4-（2-Aryloxythiazol- 5-yl）but-3-yn-2-yl）benzamides

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Chinese Journal of Chemistry 2013年第2期31卷 173-181页

作者： Youquan Zhu Pei Liu Danyang wang jin Zhang Jie cheng Yuan Ma Xiaomao Zou Huazheng Yang State Key Laboratory of Elemento-organic Chemistry Institute of Elemento-organic Chemistry Nankai University Tianjin 300071 China

A series of novel N-（4-（2-aryloxythiazol-5-yl）but-3-yn-2-yl）benzamide derivatives were designed and synthesized. Their structures were identified by IH NMR and elemental analyses. Preliminary bioassays indicated that some title compounds provided 〉 80% control of Selerotinia selerotiorum at 50 μg/mL and 〉 70% herbicidal activities against B. campestris at 100 μg/mL. Their structure-activities relationships were also discussed.

关键词： fungicides benzamide ACCase aryloxythiazole herbicide

Fluorosis Caused Cellular Apoptosis and Oxidative Stress of Rat Kidneys

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Chemical Research in Chinese Universities 2013年第2期29卷 263-269页

作者： SONG Yang wang jin-cheng XU Hui DU Zhen-wu ZHANG Gui-zhen SELIM Hamid Abdu LI Guang-sheng wang Qing GAO Zhong-li Department of Orthopedics P. R. China Central Laboratory China-Japan Union Hospital of Jilin UniversityChangchun 130033 P. R. China Pathological Laboratory Institute of Endemic Disease of Jilin University Changchun 130021 P. R. China

As the strongest electronegative element, fluorine can stimulate the production of superoxide radicals in cells. In view of the important roles of kidneys in bone metabolism, the authors analyzed the quantitative pathomor- phological characteristics of renal damage and the potential cellular apoptosis and oxidative stress mechanisms in rats treated with excessive fluoride. Wistar rats were exposed to 50 mg F （110.5 mg NaF）/L, 100 mg F-（221.0 mg NaF）/L and 150 mg F-（331.5 mg NaF）/L in drinking water for 70 and 140 d, respectively. Microscope with image analysis was used to quantitate pathomorphological changes in renal tissues of the rats. Reactive oxygen species（ROS）, the cell cycle and apoptosis of renal cells were measured by flow cytometry and TUNEL technique（terminal deoxynuc- leotidyl transferase dUTP nick end labeling）, respectively. The ion concentrations in serum and renal functional pa- rameters were detected by automatic biochemical analyzer. Quantitative analysis results demonstrate the expanded Bowman＇s space of glomerulus and obvious dilatation of renal tubule. TUNEL technique revealed that NBT/BCIP （nitro blue tetrazolium/5-bromo-4-chloro-3＇-indolylphosphate, p-toluidine salt）-staining positive apoptotic cells se- lectively located in medullocortical junction areas. The data suggest that renal damage in chronic fluorostic rats is associated with the cellular apoptosis and oxidative stress.

关键词： Fluorosis Apoptosis Oxidative stress

Lion pride optimizer:An optimization algorithm inspired by lion pride behavior

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Science China(Information Sciences) 2012年第10期55卷 2369-2389页

作者： wang Bo,jin XiaoPing & cheng Bo State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing China

In this paper,we report a novel optimization algorithm,lion pride optimizer(LPO),which is inspired by lion pride *** framework is mainly based on lion prides’ evolution process and group living *** a lion pride,brutal competition of individuals happens among male lions both within and among prides;on the other hand,each member plays an important role in the persistence of a lion *** on this framework,concepts from lion prides behavior,e.g.,the strongest males occupy nearly all mating resources,and if a new cohort of males is able to take over a pride,they will seek to kill young cubs sired by their predecessors,are employed metaphorically to design optimum searching strategies for solving continuous optimization *** the studies of the algorithm property,it is found that the LPO algorithm is not sensitive to most parameters,which shows the robustness of the algorithm and the parameters are not *** tendency of the algorithm is not *** is found that the pride update strategy and brutal competition of individuals are two main factors that contribute to the performance of *** to the test results on 23 famous benchmark functions,the LPO algorithm has better performance than the other seven state-of-the-art algorithms on both unimodal and multimodal benchmark functions;in the test of high-dimensional multimodal problems,LPO outperforms the other five algorithms on all benchmark functions.

关键词： animal behavior evolutionary algorithm lion pride optimization swarm intelligence

A discussion on the distribution of international container junction ports in northern China

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Journal of Geographical Sciences 2000年第4期10卷 53-58页

作者： HAN Zeng-lin, MA Chuang, wang cheng-jin (Department of Geography, Liaoning Normal University, Dalian 116029 China) 辽宁师范大学辽宁大连

Based on the trend of the international container traffic and the necessity to build international junction ports of container traffic in northern China, this article analyses the situation and potential of the three principal ports in northern China: Tianjin, Qingdao and Dalian. Furthermore, the authors study the distribution of international container junction ports in the Chinese north.

关键词： container junction ports distribution northern China

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我国应坚持适度有序发展煤制天然气

现代化工 2014年第6期34卷 13-15页

作者：王金成中国国际工程咨询公司北京100048

针对我国目前出现的煤制气项目投资过热现象,客观分析了国内外煤制气发展现状及存在问题,指出我国应坚持适度有序发展煤制气,合理确定煤制气在我国能源战略中的地位,并提出煤制气产业科学发展的建议。

关键词：煤制气适度有序发展建议