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The first-principles study on the doping effect of Re in Ni3Al

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Progress in Natural Science:Materials International 2008年第7期18卷 861-866页

作者： Song Yu a,*, chongyu Wanga,b, Tao Yua aCentral Iron and Steel Research Institute, Beijing 100081, China bDepartment of Physics, Tsinghua University, Beijing 100084, China Central Iron and Steel Research Institute Beijing 100081 China Department of Physics Tsinghua University Beijing 100084 China

Using first-principles density function for molecules method (DMol) and discrete variational method (DVM) based on the density functional theory, we studied the doping effect of Re in Ni3Al. The structure relaxation and the alloying energy show that Re has a strong Al site preference and leads to the local deformation, which is in agreement with the experimental results and other theoretical results. In addition, the charge density diffierence and the bond order show that Re can strongly enhance the interatomic interaction between the nearest neighbor atoms. From the density of states and the Pauli spectrum, we find that resonance states and localized states are induced by doping Re, and the doped Re atom forms the hybridized bond with the nearest neighbor atoms.

关键词： The first-principles Re Ni3Al

不同Pt分布的Pt-K/γ-Al_2O_3催化剂制备及在邻苯基苯酚制备中的催化性能

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化工学报 2012年第8期63卷 2437-2442页

作者：丁洁莲曾崇余南京工业大学环境学院江苏南京210009 南京工业大学化学化工学院江苏南京210009

采用分布浸渍法制备了以Pt为活性组分,K2SO4为助剂的Pt-K/γ-Al2O3催化剂,通过调节浸渍液中HCl浓度改变活性组分Pt在载体中的分布并用于环己烯基环己酮(Dimer)脱氢合成邻苯基苯酚(OPP),并利用比表面积(BET)、X射线衍射(XRD)、H2程序升... 详细信息

采用分布浸渍法制备了以Pt为活性组分,K2SO4为助剂的Pt-K/γ-Al2O3催化剂,通过调节浸渍液中HCl浓度改变活性组分Pt在载体中的分布并用于环己烯基环己酮(Dimer)脱氢合成邻苯基苯酚(OPP),并利用比表面积(BET)、X射线衍射(XRD)、H2程序升温还原(H2-TPR)和电子探针微量分析(EPMA)等手段对催化剂进行了表征。结果表明,通过调节浸渍液中HCl浓度的方法可有效调节催化剂的结构性质,活性组分与γ-Al2O3载体之间的相互作用以及Pt在载体上的分布。当浸渍液中HCl浓度为0.50%时,催化剂存在较高的比表面积,Pt在载体上存在最适宜的浸渍深度以及较弱的与载体之间的相互作用,从而调整了中间产物、OPP在催化剂表面的停留时间,抑制了副反应,可显著提高生成OPP的选择性。在液相空速LHSV 0.12g·g-1.h-1、H2空速33ml.g-1.h-1、温度380℃的反应条件下,环己烯基环己酮转化率为100%,OPP选择性达90%以上。

关键词：邻苯基苯酚 Pt/γ-Al2O3催化剂 Pt分布

Application of Linear Programming Model to Refugee Migrating Problem

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Journal of Applied Mathematics and Physics 2016年第5期4卷 967-977页

作者： chongyu Jiang Xiaorong Li Yandong Li School of Information Beijing Wuzi University Beijing China

The refugee immigration problem can be considered as a special “transportation problem”. Linear Programming Model is built, where two objectives with weight in the objective function, for the shortest routes that the refugees go along and the minimum number of refugees stayed in each country. An example of EU is introduced and calculated on Lingo software. The results show that the model is available to solve the refugee immigration problem in different scale.

关键词： Refugee Linear Programming Model Optimal Solution

Bonding and Fracture Characteristics at α_2/γ Interface in TiAl Alloy with B Addition

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Journal of Materials Science & Technology 1999年第1期15卷 43-47页

作者： Senying LIU Dongliang ZHAO Rongze HU and chongyu WANG(Central Iron and Steel Research Institute, Beijing 100081, China)Ping LUO(National Research Center for CRM, Beijing 100013, China) Central Iron and Steel Research Institute Beijing 100081 China National Research Center for CRM Beijing 100013 China

The bonding characteristics of (0001)α2||(111)γ interface in two-phase TiAl alloy have beeninvestigated with the recursion method. The results of bond order integral and interaction energybetween atoms are presented. The effects of B on atoms bonding both in constituent phase andat the α2/γ interface have been studied. The correlation between the mechanical propertiesof the alloy and the bonding at the interface has been discussed. The results suggest that Bsegregation to the interface benefits the ductility. This is supported by the related experiment.

关键词： TiAl Bonding and Fracture Characteristics at Interface in TiAl Alloy with B Addition

Environmental factors affecting growth of grasses，herbs and woody plants on a sanitary landfill

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Journal of Environmental Sciences 1994年第4期6卷 504-513页

作者： Lan chongyu Wong Minghung(Department of Biology and Center for Waste Recycling &Environmental Biotechnology, Hong Kong BaptistCollege, 224 Waterloo Road, Kowloon, Hong Kong)

The present study aims at studying relationships between various environmental factors andplant performance on a completed sanitary landfill. Three sites were chosen for comparison: an on-sitelow landfill gas region with a rich vegetation growth (Site L) , an on-site high landfill gas region with apoor vegetation growth (Site H), an off site control region (Site N) which located close to the GinDrinkers' Bay landfill. In Site H, where the levels of methane and carbon dioxide were higher, growth oftrees, shrubs and climbing plants are adversely affected, but not herbs and grasses. Analysis of correla-tion coefficient indicated that carbon dioxide and methane showed a negative correlation with the growth oftrees and shrubs. In Site H, the higher levels of conductivity, Kjeldah-N, Ammonium-N, and variousheavy metals, such as Mn were also exerted their adverse effect on plant growth. Trees tolerant to land-fill gas , e. g. Acacia confusa . would be a better choice for planting on sanitary landfills , in addition to theuse of shallow-rooted trees. Grasses and herbs are less susceptible to landfill gas due to their shallow-rootsystems. Hydroseeding of grasses would ensure a better plant coverage in areas with a moderate level oflandfill gas. Installation of a ventilation system might be needed for areas with a high level of landfill gas.

关键词： sanitary landfill restoration vegetation landfill gas soil factors.

Spatial and temporal variability of daily precipitation in Haihe River basin, 1958-2007

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Journal of Geographical Sciences 2010年第2期20卷 248-260页

作者： CHU Jianting XIA Jun XU chongyu LI Lu WANG Zhonggen Key Laboratory of Water Cycle ＆ Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Institute of Physics ＆ Meteorology University of Hohenheim Garbenstr. 30 D-70955 Stuttgart Germany Department of Geosciences University of Oslo P O BOX 1047 Blindern N-0316 Oslo Norway

The seasonal variability and spatial distribution of precipitation are the main cause of flood and drought events. The study of spatial distribution and temporal trend of precipitation in river basins has been paid more and more attention. However, in China, the precipitation data are measured by weather stations （WS） of China Meteorological Administration and hydrological rain gauges （RG） of national and local hydrology bureau. The WS data usually have long record with fewer stations, while the RG data usually have short record with more stations. The consistency and correlation of these two data sets have not been well understood. In this paper, the precipitation data from 30 weather stations for 1958-2007 and 248 rain gauges for 1995-2004 in the Haihe River basin are examined and compared using linear regression, 5-year moving average, Mann-Kendall trend analysis, Kolmogorov-Smirnov test, Z test and F test methods. The results show that the annual precipitation from both WS and RG records are normally distributed with minor difference in the mean value and variance. It is statistically feasible to extend the precipitation of RG by WS data sets. Using the extended precipitation data, the detailed spatial distribution of the annual and seasonal precipitation amounts as well as their temporal trends are calculated and mapped. The various distribution maps produced in the study show that for the whole basin the precipitation of 1958-2007 has been decreasing except for spring season. The decline trend is significant in summer, and this trend is stronger after the 1980s. The annual and seasonal precipitation amounts and changing trends are different in different regions and seasons. The precipitation is decreasing from south to north, from coastal zone to inland area.

关键词： climate change spatial and temporal variability of precipitation Mann-Kendall method Kolmogorov-Smirnov test Z test F test Haihe River basin

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利用顶部脉冲吸气控制三维方形棱柱气动力

中南大学学报（自然科学版） 2023年第4期54卷 1407-1415页

作者：邓国浩王汉封赵崇宇尹亚鹏中南大学土木工程学院湖南长沙410075 中南大学高速铁路建造技术国家工程实验室湖南长沙410075

通过风洞实验研究三维柱体顶部前沿狭缝脉冲吸气对其气动力与尾流的控制效果。实验模型为高宽比H/d=5的方柱,均匀来流速度U∞=10 m/s,雷诺数Re=27000,狭缝入口吸气速度与来流风速相同。研究结果表明:相对于无控制工况,脉冲吸气对柱体气... 详细信息

通过风洞实验研究三维柱体顶部前沿狭缝脉冲吸气对其气动力与尾流的控制效果。实验模型为高宽比H/d=5的方柱,均匀来流速度U∞=10 m/s,雷诺数Re=27000,狭缝入口吸气速度与来流风速相同。研究结果表明:相对于无控制工况,脉冲吸气对柱体气动力有明显抑制作用;当脉冲吸气系数f*=0.2时,脉冲吸气与定常吸气对柱体气动力的抑制效果相当;随f*增大,柱体阻力与脉动升力仍有所减小,但减小幅度有限;顶部脉冲吸气不仅能明显削弱柱体顶部附近气动力,而且对柱体中下部气动力抑制效果比定常吸气对柱体气动力抑制效果好;顶部脉冲吸气在自由端剪切流中形成周期性大尺度涡结构,增强了自由流与尾流动量交换。

关键词：风洞实验三维柱体脉冲吸气剪切流主动控制

Spatial Interpolation of Daily Precipitation in China:1951-2005

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Advances in Atmospheric Sciences 2010年第6期27卷 1221-1232页

作者： Deliang CHEN Tinghai OU Lebing GONG chongyu XU 李维京 Chang—Hoi HO 钱维宏 Department of Earth Sciences University of Gothenburg Gothenburg Sweden School of Geography Beijing Normal University Beijing 100875 Department of Earth Sciences Uppsala University Sweden Department of Geosciences University of Oslo Norway Laboratory for Climate Studies/National Climate Center China Meteorological Administration Beijing 100029 School of Earth and Environmental Sciences Seoul National University Korea School of Physics Peking University Beijing 100871

Climate research relies heavily on good quality instrumental data; for modeling efforts gridded data are needed. So far, relatively little effort has been made to create gridded climate data for China. This is especially true for high-resolution daily data. This work, focuses on identifying an accurate method to produce gridded daily precipitation in China based on the observed data at 753 stations for the period 1951-2005. Five interpolation methods, including ordinary nearest neighbor, local polynomial, radial basis function, inverse distance weighting, and ordinary kriging, have been used and compared. Cross-validation shows that the ordinary kriging based on seasonal semi-variograms gives the best performance, closely followed by the inverse distance weighting with a power of 2. Finally the ordinary kriging is chosen to interpolate the station data to a 18 km× 18 km grid system covering the whole country. Precipitation for each 0.5°×0.5° latitude-longitude block is then obtained by averaging the values at the grid nodes within the block. Owing to the higher station density in the eastern part of the country, the interpolation errors are much smaller than those in the west （west of 100°E）. Excluding 145 stations in the western region, the daily, monthly, and annual relative mean absolute errors of the interpolation for the remaining 608 stations are 74%, 29%, and 16%, respectively. The interpolated daily precipitation has been made available on the internet for the scientific community.

关键词： daily precipitation spatial interpolation ordinary kriging gridded data China

Bcl-2 gene and its family genes Bax,Bcl-Xl as well as Fas/Apo-1 and their clinical significance in acute leukemia

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Chinese Medical Journal 1998年第8期 10-13页

作者： Chen Yan , Zhou Jianfeng , Yue Beibei , Xiang Zhifu , Song Xiaohua Li chongyu and Wang Bianming 

Objective To study the suppressing genes of apoptosis, namely Bcl-2, its family genes Bax, Bcl-Xl, and the inducing gene of apoptosis Fas/*** The techniques of cytoimmuno-histiochemical stains, Western blotting and Northern blotting were used. Results It was found that the antigens of Bcl-2 in acute myelogenous leukemia (AML) and acute lymphocytic (ALL) was higher than that in the normal (P0.05). In CR group the expression of Bcl-2 mRNA was obviously lower than that of NR one (P0.05). There was difference of Bcl-Xl mRNA in two groups (P<0.01).The expression Fas/Apo-1 in leukemia was lower than that in normal people (P<0.01). But in CR and NR, there was no difference with cytoimmuno-histiochemical stain and Western blotting. Conclusions The Changes of genes and their proteins are significant theoretically and clinically. The antigen expression of Bcl-2 and the expression of Bcl-2 mRNA may be considered as a prognostic index for AML.

关键词： Bax,Bcl-Xl family and its acute leukemia Apo genes well