重庆降水和赤道东太平洋海温相关的多时间尺度特征

采用小波分析和滑动相关技术，分析了重庆夏季降水和赤道东太平洋冬季海温的多时间尺度变化特征，发现两者之间的相关性在不同时间尺度上存在显著差异，而且这种相关性具有多时间尺度特征。

CHARACTERISTICS OF QUASI-PERIODIC OSCILLATIONS DURING SEA FOG EVENTS

Based on the high-resolution datasets collected in a sea fog field experiment at the northern coast of South China Sea,the variations of liquid water content (LWC) and net longwave radiation flux (NLRF) during two sea fog events on 16th-17th and 18th-19th March,2008 are exaimeed by wavelet analysis,and the cooling mechanisms for fog formation and persistence are also investigated.The main results are shown as follows.(1) Sea fog may develop and persist whether it is cloudy or not aloft.However,when there is cloud aloft the LWC is less and wind speed in sea fog is higher than that in the clear sky.(2) The quasi-periodic oscillations (QPOs) of NLRF are observed in the formation stage of the two fogs.QPOs of LWC are only found in the developing stage no matter with cloudless or cloudy condition.(3) It is likely that sea fog forms by the cooling effects of longwave radiation and develops through the vertical mixing induced by the radiative cooling at the upper level.(4) During sea fog development and persistence,other mechanisms could also play important roles in fog-layer cooling,such as turbulent heat transport and radiation transport between air-sea interfaces.

Watershed Prioritization of Palar Sub-watershed Based on the Morphometric and Land Use Analysis

Morphometric analysis is an indispensable tool for hydrological investigation that involves the development and management of drainage basin. This study characterizes the micro watersheds in the Palar sub-watershed using morphometric analysis and assesses its risk by land use and land cover features in a particular micro watershed. Palar sub-watershed is divided into 6 micro watersheds for prioritization based on morphometric and land use analysis. Several morphometric parameters （linear, shape and relief） are determined from the drainage map; ranks are assigned based on their capacity to induce erodability and degradation. Final ranking is based on the composite index calculated from the sum of the ranks of each morphometric parameter. Morphometric analysis reveals micro watersheds 5 and 6 as most susceptible and 2 and 3 as low susceptible. Land use is mapped using IRS ID LISS III satellite data. The risk in terms of watershed degradation involved to each micro watershed is based on the ranks of each land use feature, obtained from a similar composite index as that of morphometric analysis. Land use analysis shows that micro watersheds 2 and 4 fall under high priority category while 5 and 6 under low priority category. Integration of the morphometric and land use analysis shows that only microwatershed 1 falls under the same category in both analyses. Control measures are suggested to contain degradation depending on its specific land use pattern and morphometric features. This study ean be used to prepare a comprehensive watershed plan for the development or for planning resource conservation strategies, by integrating land use features with the drainage characteristics of the region, in particular for a hill ecosystem as the prioritization is at micro level.

A new method for reservoir fluid identification

The wavelet transform （WT） method has been employed to decompose an original geophysical signal into a series of components containing different information about reservoir features such as pore fluids, lithology, and pore structure. We have developed a new method based on WT energy spectra analysis, by which the signal component reflecting the reservoir fluid property is extracted. We have successfully processed real log data from an oil field in central China using this method. The results of the reservoir fluid identification agree with the results of well tests.

7-difluoromethoxyl-5,4'-di-n-octylgenistein inhibits growth of gastric cancer cells through downregulating forkhead box M1

AIM: To investigate whether the 7-difluoromethoxyl-5, 4'-di-n-octylgenistein (DFOG), a novel synthetic genistein analogue, affects the growth of gastric cancer cells and its mechanisms. METHODS: A series of genistein analogues were prepared by difluoromethylation and alkylation, and human gastric cancer cell lines AGS and SGC-7901 cultured in vitro were treated with various concentrations of genistein and genistein analogues. The cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cells were incubated by DFOG at different concentrations. The growth inhibitory effects were evaluated using MTT and clonogenic assay. The distribution of the phase in cell cycle was analyzed using flow cytometric analysis with propidium iodide staining. The expression of the transcription factor forkhead box M1 (FOXM1) was analyzed by reverse transcription-polymerase chain reaction and Western blotting. The expression levelsof CDK1, Cdc25B, cyclin B and p27KIP1 protein were detected using Western blotting. RESULTS: Nine of the genistein analogues had more effective antitumor activity than genistein. Among the tested analogues, DFOG possessed the strongest activity against AGS and SGC-7901 cells in vitro. DFOG significantly inhibited the cell viability and colony formation of AGS and SGC-7901 cells. Moreover, DFOG efficaciously arrested the cell cycle in G2/M phase. DFOG decreased the expression of FOXM1 and its downstream genes, such as CDK1, Cdc25B, cyclin B, and increased p27KIP1 at protein levels. Knockdown of FOXM1 by small interfering RNA before DFOG treatment resulted in enhanced cell growth inhibition in AGS cells. Up-regulation of FOXM1 by cDNA transfection attenuated DFOG-induced cell growth inhibition in AGS cells. CONCLUSION: DFOG inhibits the growth of human gastric cancer cells by down-regulating the FOXM1 expression.

Entropy Analyses of Droplet Combustion in Convective Environment with Small Reynolds Number

This paper analyzes the entropy generation rate of simple pure droplet combustion in a tempera-ture-elevated air convective environment based on the solutions of flow, and heat and mass transfer between the two phases. The flow-field calculations are carried out by solving the respective conservation equations for each phase, accounting for the droplet deformation with the axisymmetric model. The effects of the temperature, velocity and oxygen fraction of the free stream air on the total entropy generation rate in the process of the droplet combustion are investigated. Special attention is given to analyze the quantitative effects of droplet deformation. The results re-veal that the entropy generation rate due to chemical reaction occupies a large fraction of the total entropy generated, as a result of the large areas covered by the flame. Although, the magnitude of the entropy generation rate per volume due to heat transfer and combined mass and heat transfer has a magnitude of one order greater than that due to chemical reaction, they cover a very limited area, leading to a small fraction of the total entropy generated. The en-tropy generation rate due to mass transfer is negligible. High temperature and high velocity of the free stream are advantageous to increase the exergy efficiency in the range of small Reynolds number (<1) from the viewpoint of the second-law analysis over the droplet lifetime. The effect of droplet deformation on the total entropy generation is the modest.

Wavelet analysis of pressure fluctuation signals in a gas-solid fluidized bed

It has been shown that much dynamic information is hidden in the pressure fluctuation signals of a gas-solid fluidized bed. Unfortunately, due to the random and capricious nature of this signal, it is hard to realize reliable analysis using traditional signal processing methods such as statistical analysis or spectral analysis, which is done in Fourier domain. Information in different frequency band can be extracted by using wavelet analysis. On the evidence of the composition of the pressure fluctuation signals, energy of low frequency (ELF) is proposed to show the transition of fluidized regimes from bubbling fluidization to turbulent fluidization. Plots are presented to describe the fluidized bed's evolution to help identify the state of different flow regimes and provide a characteristic curve to identify the fluidized status effectively and reliably.

Multiple Time Scale Analysis of River Runoff Using Wavelet Transform for Dagujia River Basin, Yantai, China

Based on monthly river runoff and meteorological data, a method of Morlet wavelet transform was used to analyze the multiple time scale characteristics of river runoff in the Dagujia River Basin, Yantai City, Shandong Province. The results showed that the total annual river runoffin the Dagujia River Basin decreased significantly from 1966 to 2004, and the rate of decrease was 48× 10^6ma/10yr, which was higher than the mean value of most rivers in China. Multiple time scale characteristics existed, which accounted for different aspects of the changes in annual river runoff, and the major periods of the runofftime series were identified as about 28 years, 14 years and 4 years with decreasing levels of fluctuation. The river runoff evolution process was controlled by changes in precipitation to a certain extent, but it was also greatly influenced by human activities. Also, for different time periods and scales, the impacts of climate changes and human activities on annual river runoff evolution occurred at the same time. Changes in the annual river runoffwere mainly associated with climate change before the 1980s and with human activities after 1981.

Multi-Time Scale Analysis of Runoff at the Yangtze Estuary Based on the Morlet Wavelet Transform Method

Runoff series of the Yangtze River presents an intricate variation tendency under the reinforced influence of human activities.The Morlet Wavelet Transform method has been applied to analyze the annual runoff data from 1950 to 2011 at the Yangtze River Estuary.It can clearly reveal the multi-time scales structure,break point,change and distribution of periodic variation in the different time scales of the runoff series.The main conclusions are that:1) Repeated periodic oscillations accompanied by an extremely large fluctuation are presented in the runoff series with an obvious difference between wet and dry years,and the major periods of the time series are about 3,8,16 and 23 years respectively.Among them,the presented maximum periodic oscillation is 23 years scale.2) In the 23-year time scale,the wet periods are 1950-1958,1969-1980 and 1992-2003,and the dry periods are 1959-1968,1981-1991 and 2004-2011.3) It can be predicted from the view of long time scales that the low annual runoff will likely occur in the near future.

Measurement and Prediction of Interfacial Area on a DistiIlation Tray

In this paper the modern electron optical equipment is used to translate the clear image of speed moving bubbles in bubbling liquid on a sieve tray into the digital information stored in computer, and the computer aided image processing technique is utilized to measure the bubble size distributions and interfacial areas under various operating conditions. And the dynamic behavior of bubbles in turbulent liquid is analyzed theoretically; the mechanism of bubble deformation and breakage is explored on the basis of Kolmogoroff′s isotropic turbulence hypothesis; the mathematical model for predicting the gas liquid interfacial area is proposed. The comparison between the simulated results and the experimental data shows that the model is higher in accuracy, simple in form and convenient in use.

Characteristics of Variation in Runoff across the Nyangqu River Basin in the Qinghai-Tibet Plateau

Using annual nature runoff data from 1961–2000 for the Qinghai-Tibet plateau Nyangqu River, the Mann-Kendall method and wavelet transform were adopted to analyse runoff variation characteristics for the Nyangqu River. The results show that the annual change in runoff is relatively stable and that the intra-annual distribution of the runoff is extremely uneven. The disparity in runoff between wet seasons was significant. The runoff for June-September accounted for 65% of the whole year and the highest monthly runoff accounted for 24.56%. From 1961-2000, runoff showed a significant increasing trend with an abrupt increase in 1985. The 5-8 years oscillation period of the runoff was most notable and the 10-15 years period was relatively notable. The principal periods of annual runoff for Shigatse station and Gyantse station were 5a and 7a. The second were 13a and 12 years. Increasing glacial melt water caused by rising temperatures may be the main reason for increased runoff in the Nyangqu River.

Inter-decadal Variability of the East Asian Summer Monsoon and Its Impact on Hydrologic Variables in the Haihe River Basin, China

Wavelet analysis and Mann-Kendall tests are employed to evaluate the variation in the East Asian summer monsoon（EASM） and hydrological variables in the Haihe River basin calculated by the Variable Infiltration Capacity model. The relationships between those variables and the EASM are also examined. The results indicate consistent 40 a periodic variation in both the hydrological variables and the EASM. The hydrologic variables show downward trends in the Haihe River basin over the past 60 years, especially in piedmont regions of the Taihang-Yan Mountains. The variables are closely related to the EASM, whose continuous weakening since the 1970 s has resulted in prolonged drought and severe water shortages in the basin. The periodicity of the EASM index was analyzed using continuous wavelet transform methods. We found the most significant periodic signal of the EASM is ~80 years; therefore, the EASM may reinforce and reach a maximum in the 2040 s, resulting in more precipitation and other impacts on basin water resources. Hydrologic variables in the basin in the 2040 s are predicted, and their spatial distributions in the Haihe River basin are also discussed. These results allow for the estimation of water resources under forecasted EASM, which will be useful for water resources management in the Haihe River basin.