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Direct numerical simulation of a supersonic turbulent boundary layer on a flat plate and its analysis

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Science china(physics,Mechanics & Astronomy) 2005年第5期48卷 626-640页

作者： HUANG Zhangfeng1, ZHOU Heng1,2.& LUO Jisheng1,2.1. department of Mechanics, Tianjin university, Tianjin 300072.{2. 2. Liu-Hui Center of Applied Mathematics, Nankai university and Tianjin university, Tianjin 300072.{2. department of Mechanics Tianjin University Tianjin China Liu-Hui Center of Applied Mathematics Nankai University and Tianjin University Tianjin China

Temporal mode direct numerical simulation (DNS) has been done for a supersonic turbulent boundary layer on a flat plate with Mach number 4.5. It was found that the mean flow profile, the normal-wise distribution of turbulent Mach number and the root mean square (RMS) of the fluctuations of various variables, as well as the Reynolds stresses, bore similarity in nature, when the turbulence reached a fully developed state. But the compressibility effect was strong and must be considered. The strong Reynolds analogy (SRA) and the Morkovin hypothesis were no longer valid. From the end of transition to the fully developed state of turbulence, it was in the transient period, for which the similarity did not hold.

关键词： turbulence, similarity, compressibility effect, supersonic boundary layer, direct numerical simulation.

Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

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Acta Oceanologica Sinica 2003年第1期22卷 69-74页

作者： Han Mei Geography department, shandong normal university, Jinan 2.0014,{2. Geography department Shandong Normal University Jinan 250014 China

The palaeochannel evolution in the study region is divided into four stages by such methods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point. Palaeochannels are the main passageways through which the sea water intrudes at a higher speed, through many means and in a changeable dynamic state.

关键词： Palaeochannel sea water intrusion south coastal plain of Laizhou Bay

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1 & TAN Wenchang2.1. Institute of Applied Mathematics, School of Math & System Science, shandong university, Jinan 2.0100,{2. 2. State Key Laboratory of Turbulence and Complex Systems & department of Mechanics and Engineering Science, Peking university, Beijing 100871,{2. Institute of Applied Mathematics School of Math & System Science Shandong University Jinan China State Key Laboratory of Turbulence and Complex Systems & department of Mechanics and Engineering Science Peking University Beijing China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

Variable Separation Solution for(1+1)-Dimensional Nonlinear Models Related to Schrdinger Equation

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Communications in Theoretical physics 2004年第10期42卷 568-572页

作者： XU Chang-Zhi~(1,2. ZHANG Jie-Fang~11 Institute of Nonlinear physics,Zhejiang normal {2.,Jinhua 32.004,china2.department of physics and Mathematics,Jinhua Educational College,Jinhua 32.000,china Institute of Nonlinear physics Zhejiang Normal University Jinhua 321004 China department of physics and Mathematics Jinhua Educational College Jinhua 321000 China

A variable separation approach is proposed and successfully extended to the(1+1)-dimensional *** new exact solution of(1+1)-dimensional nonlinear models related to Schr(?)dinger equation by the entranceof three arbitrary functions is *** special types of soliton wave solutions such as multi-soliton wave solution,non-stable soliton solution,oscillating soliton solution,and periodic soliton solutions are discussed by selecting thearbitrary functions appropriately.

关键词： variable separation approach (1+1)-dimensional nonlinear models solution of soliton

Near infrared lights emission of ^(40)Ar^(16+) impacting on metal surfaces

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Science china(physics,Mechanics & Astronomy) 2009年第7期52卷 1021-1026页

作者： ZHANG XiaoAn1,2. XIAO GuoQing2. YANG ZhiHu2. WANG Li1 & ZHAN WenLong2.1 department of physics, Xianyang {2. university, Xianyang 712.00, china 2.Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china department of physics Xianyang Normal University Xianyang China Institute of Modern physics Chinese Academy of Sciences Lanzhou China

The highly charged ion 40Ar16+ with the velocity (kinetic energy EK=150 keV, velocity V=8.5×105 m/s) smaller than Bohr velocity (VBohr=2.9×106 m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.

关键词： infrared light lines X-ray neutralization highly charged ions

Shape phase transitions in nuclei:Effective order parameters and trajectories

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 88-97页

作者： ZHANG Yu1,2. HOU ZhanFeng2.& LIU YuXin2.3 1department of physics, Liaoning {2. university, Dalian 11602., china 2.0} of physics and the State Key Laboratory of Nuclear physics and Technology, Peking university, Beijing 100871, china 3Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 72.000, china department of physics Liaoning Normal University Dalian China department of physics and the State Key Laboratory of Nuclear physics and Technology Peking University Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

We analyze systematically the effective order parameters in nuclear shape phase transition both in experiments and in the interacting boson model. We find that energy ratios and B(E2. ratios can distinguish the first from the second-order phase transition in theory above a certain boson number N (about 50), but in experiments, only those quantities, such as E(L1+)/E(02.) and B(E2. (L+2.1 → L1)/B(E2. 2. → 01), etc., of which the monotonous transitional behavior in the second-order phase transition is broken in the first order phase transition independent of N, are qualified as the effective order parameters. By implementing the originally proposed effective order parameters and the new ones, we find that the isotones with neutron number Nn = 62.are a trajectory of the second order phase transition. In addition, we predict that the transitional behavior of isomer shifts of Xe, Ba isotopes and Nn = 62.isotones is approximately monotonous due to the finiteness of nuclear system.

关键词： nuclear shape phase transition interacting boson model effective order parameter finite particle number effect transition trajectory

Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of shandong Province,china

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Chinese Geographical Science 2024年第1期34卷 149-167页

作者： LI Li LYU Xiao ZHANG Anlu NIU shandong PENG Wenlong School of Public Administration Huazhong Agricultural UniversityWuhan430070China department of Geography University of ZurichZurich8057Switzerland School of Humanities and Law Northeastern UniversityShenyang110169China School of Geography and Tourism Qufu Normal UniversityRizhao276800China

Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural ***,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU *** address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating *** subsequently employed econometric models to analyze the significant factors that impact *** findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment ***,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in ***,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting ***,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for *** trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management ***,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters *** insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate *** conclusion,we propose research avenues for further enriching the SICLU framework to ensur

关键词： sustainable intensification of cultivated land use(SICLU) self-efficacy status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas shandong,china

Gene Expression of Ornithine Decarboxylase in Lung Cancers and Its Clinical Significance

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Acta Biochimica et Biophysica Sinica 2006年第9期38卷 639-645页

作者： Hui TIAN~1* Qing HUANG~1 Lm LI~1 Xian-Xi LIU~2.Yan ZHANG~2. 1 department of Thoracic Surgery,shandong {2. Qi Lu Hospital,Jinan 2.0012.china 2.department of Medicine,Medical Molecular Biology Experimental Center,shandong {2.,Jinan 2.0012.china department of Thoracic Surgery Shandong University Qi Lu HospitalJinan 250012 China department of Medicine Medical Molecular Biology Experimental Center Shandong UniversityJinan 250012 China

Lung cancer is one of the most lethal cancers in china because of its high incidence and *** decarboxylase （ODC）,an important enzyme in polyamine biosynthesis,is increased incancer *** chemotherapeutic agents aimed at reducing ODC expression show inhibitory effects oncancer cell growth,so ODC can be useful in gene diagnosis and gene therapy of *** this study,weexamined the effect of antisense ODC on lung cancer cells.A-549 cells were infected with rAd-ODC/Ex3as,a recombinant adenovirus containing the cytomegalovirus promoter,green fluorescent protein gene and 12.bp antisense *** cell cycle was evaluated by flow cytometry.A nude mouse xenograft model wasused in the tumorigenicity *** transcription-polymerase chain reaction,Western blot and immuno-histochernistry were used to study the expressions of ODC on lung *** was found that the growth ofcells infected with rAd-ODC/Ex3as was substantially inhibited and cells were arrested at *** with rAd-ODC/Ex3as can suppress tumor formation in a nude mouse xenograft *** of ODC mRNA and ODC protein levels in lung cancer tissues was significantly higher than thatin normal tissues （P<0.05）,which correlated significantly with the stage of lung cancer （P<0.05）.This studysuggested that rAd-ODC/Ex3as has antitumor activity in human lung cancer *** ODC gene might playan important role in lung cancer and the overexpression of ODC might be related to the occurrence anddevelopment of lung cancer.

关键词： polyamine biosynthesis lung neoplasm ornithine decarboxylase A-549 cell line

Stochastic bi-resonance induced by external noise for Ca^2. signaling in hepatocytes

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Science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2.HOU Zhonghuai1 & XIN Houwen1 1.department of Chemical physics,{2. of Science and Technology of china,Hefei 2.002.,china 2.College of physics and Electronic Information,Anhui normal {2.,Wuhu 2.1000,china department of Chemical physics University of Science and Technology of China Hefei China College of physics and Electronic Information Anhui Normal University Wuhu China

The influence of external noise on intracellular Ca2. oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2. oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.