广义双尺度收敛和具分层周期结构系数的偏微分方程的均匀化(英文)

我们给出了广义双尺度收敛的概念 .用广义双尺度收敛的理论我们研究了某些具分层周期结构系数的线性和半线性偏微分方程 .

Cell Cycle Kinetic Analysis in the Cortical Regions of the Lentil Primary Root During Germination

Cell cycle kinetic activity in the cortical cells of the lentil (Lens culinaris Me-die. cv. Verte du Puy) primary root during germination was examined both temporally and spatially. Immunohistochemical and cytological evidence indicated that DNA replication and cell division started in the cortical cells of tire lentil primary root after around 13 and 17 h of imbibition, respectively. The first cells in DNA synthesis and the First mitotic figures all appeared in the cortical cells about I mm front the root-cap junction, but these divided cells had synthesized their DNA during the maturity of seed instead of during germination. The kinetic pattern of activity of the first cell cycle showed that these cells were not activated synchronously, but re-entered the cell cycle in turn depending on their places in the root tip, However, the adjacent cells partially synchronously proceeded their cell cycle.

A P.hysical Numerical Ionospheric Model and Its Simulation Results

This paper describes the construction of a one-dimensional time-dependent theoretical ionospheric model, which is based on numerical solution of continuity and momentum equations for , and NO+. The model is designed to have an option to incorporate the observational ionospheric characteristic parameters into the numerical model to indirectly determine the upper boundary condition when solving the transport equations of O+. A preliminary simulation result of the model when used to simulate the ionosphere during April 18 ~ May 10, 1998, which includes both quiet and disturbed periods, showed that the model constructed is able to reproduce the observational results reasonably well both for quiet and disturbed periods.

Investigation of the environmental impacts of steel deck pavement based on life cycle assessment

To investigate the environmental impacts of steel deck pavement through the whole life cycle,the steel deck pavement was divided into five stages:raw materials production,asphalt mixture mixing,pavement construction,operation management,and pavement removing stage.Based on the process-based life cycle assessment(PLCA)method,the calculation methods of energy consumption and gas emissions of two typical steel deck pavement systems(EA+EA pavement and GA+SMA pavement)were determined.The data lists of two pavements were analyzed,and the calculation model was built.Four characteristic indices including primary energy demand(PED),global warming potential(GWP),acidification potential(AP)and respiratory inorganics(RI)were used to quantify the environmental impacts of two pavements.The results show that the environmental impact of the GA+SMA pavement is more than 1.3 times that of the EA+EA pavement.Moreover,the critical stage of energy-saving and emission-reduction of EA+EA pavement and GA+SMA pavement are the raw material production stage and asphalt mixture mixing stage,respectively.

Liver cell adenoma showing sequential alteration of radiological findings suggestive of well-differentiated hepatocellular carcinoma

A liver tumor 35 mm in diameter was found incidentally in a 40-year-old woman who had no history of liver diseases or the use of oral contraceptives.Radiological diagnostics showed the typical findings of liver cell adenoma(LCA).Dynamic computed tomography revealed that the tumor showed a homogenous enhancement in the arterial phase and almost the same enhancement as the surrounding liver parenchyma in the delayed phase.The tumor was found to contain fat on magnetic resonance imaging.A benign fat containing liver tumor was suggested.However,radiological findings altered,which caused us to suspect that a welldifferentiated hepatocellular carcinoma(HCC)containing fat was becoming dedifferentiated.Partial hepatectomy was performed and the pathological findings showed the typical findings of LCA.This case was an extremely rare LCA,which had no background of risk for LCA and developed the sequential alteration of the radiological findings to suspect well-differentiated HCC.

Variations and Controlling Factors of the Coccolith Weight in the Western Pacific Warm Pool over the Last 200 ka

Using a coccolith weight analytic software(Particle Analyser), we analyze most abundant coccolith species in a sediment core from the central Western Pacific Warm Pool(WPWP) and calculate coccolith size and weight variations over the last 200 ka. These variations are compared with the trends of sea surface temperature(SST), primary productivity(PP), sea surface salinity(SSS), and insolation. Our results demonstrate that the size and weight of the coccoliths varied in response to variations of these factors, and their average total weight is primarily related to the relative abundance of the dominant species GEO(Gephyrocapsa oceanica). The variation in weight of EMI(Emiliania huxleyi) and GEE(Gephyrocapsa ericsonii) are mainly influenced by nutrients, and the variation of GEM(G. muellerae conformis) and GEO(G. oceanica) weight are mainly influenced by SST. For all of the taxa weight, PP and SST present apparent precession or semi-precession cycles, we consider that the mono-coccolith weight of the Equatorial Western Pacific is primarily affected by precession drived thermocline and nutricline variation.

农业碳足迹研究——以浙江省为例

本文运用2008年《中国能源统计年鉴》、《浙江省投入产出表》统计数据和IPCC相关实验数据,采用分层投入产出—生命周期评价法,构建五个层级对农业系统碳足迹进行量化,深度分析农业碳排放的数量和结构特征。研究表明:(1)按照国际惯例IPCC核算的农业碳排放只占总碳足迹的43.55%,隐含在农用能源和农业工业投入品生产过程中的碳排放被忽视或被低估,这将严重影响农业系统减排和低碳农业发展战略的制定;(2)从农业碳足迹结构来看,农业种植、养殖活动本身排放的温室气体所占比重不大;农用能源直接和间接碳排放、工业投入品全生命周期碳排放、农业废弃物最终处置是农业源温室气体最重要的三大类来源;其中以化肥(氮肥)生产、运输、施用过程中引致的碳排放在整个农业系统碳排放中所占比重最大;(3)农业技术和管理措施具有积极的减排增汇效应。

Analysis of the ionospheric variability based on wavelet decomposition

In this work,the ionospheric variability is analyzed by applying the wavelet decomposition technique to the noontime fo F2,F10.7,interplanetary magnetic field(IMF)Bz,Ap,and lower thermospheric temperature at pressure of 10?4 h Pa in 2002.Results show that the variance of periodic oscillations in the ionosphere is largest in the 2–4-day period and declines with the increase of the period.The maximum variance of the periodic oscillations in solar irradiation is in the 16–32-day period.For geomagnetic activities,most of the variance is about equally distributed on intervals of periods shorter than 32 days.Variance distributions of IMF Bz and lower thermospheric temperature are similar to those of the ionosphere.They show the maximum in the 2–4-day period and decline with the increase of the period.By analyzing the distributions of the variances,the potential connections between the ionosphere and the external sources are discussed.