快速筑堤技术——鲎式轻质堤坝的结构和筑堤方法

针对软基堤坝稳定性差,容易沉陷滑移,土石方堆不上,工期长,无法快速施工等问题,提出了鲎式轻质堤坝结构和筑堤方法,又称"松垒筑堤法".它减轻了易沉陷部位的质量,均衡堤坝荷重,增强整体稳定性,提高强度,使堤坝与地基溶为一体,消除了堤坝的不均匀沉降;是一种在软弱地基上应用仿生结构的筑堤方法.     

Light Curve Analysis of Early-Type Close Lmc Binaries

Results are presented of an analysis of eclipsing binaries in the Large Magellanic Cloud. The sample of close OB-type stars was taken from the MACHO microlensing survey. The present study was restricted to systems with orbital periods shorter than 2 days and V and R light curves with large eclipse amplitudes, high S/N and homogeneous and dense phase coverage. Problems encountered during the analysis are discussed, especially with respect to the degeneracy of photometric mass ratios and other parameter correlations.     

New Techniques and Limitations of Light Curve Analysis

The solution of light curves of eclipsing binaries provides the simplest way of measuring the basic physical parameters of stars. The development of computers and numerical methods enables us to perform an analysis of large amount of photometric data by comparing it to more and more sophisticated physical models which are also suitable for stellar systems with different peculiarities. Nevertheless, some parameters of stellar systems are poorly determined by light curves alone, and simultaneous fitting together with other data is preferable. The progress of instrumentation not only improves the precision and resolution of data, but also overcomes the classical gaps between stellar systems observable as visual, photometric and spectroscopic binaries. This opens new problems in the development of techniques of data analysis, which can be treated as a generalization of light curve modeling. Some of these directions are outlined here. In particular, the disentangling of spectra with line-profile variability due to proximity effects is discussed.     

再探伽玛射线暴中能量与脉冲宽度的依赖关系

探索来源于BATSE(http://cossc:gsfc:nasa:gov/batse)的GRB(Gamma-Ray Burst,伽玛射线暴)观测数据的半峰宽度(FWHM)与能量之间的关系,基于64个用KRL函数模型(即,文[1]中的(22)式)能很好地拟合的FRDE(Fast Rise and Exponential Decay,快速上升指数下降)型脉冲样本。发现64个样本中有63个的半峰宽度(FWHM)与能量之间的关系属于平台—幂率—平台型结构或峰型结构。64个样本的半峰宽度(FWHM)与能量之间的关系在观测中可详细分为5种类型:a)有34个样本为幂率形式关系;b)18个样本为低能段平台关系;c)有7个样本为高能段平台关系;d)4个样本为峰型结构关系;e)另外有1个样本为其他结构。结果表明:GRB观测数据的半峰宽度(FWHM)与能量之间的确存在有幂率的关系。此结果进一步确认了文[2](Qin etal 2005)的观点,即半峰宽度(FWHM)与能量之间的关系是由于火球模型的多普勒效应(Doppler effect)导致的。     

Ubv Photometry And Light Curve Analysis Of Bx And

We present a photometric study of the near contact binary BX And. UBV photometric observations have been carried out in 1996, 1997, 1998 and 2000. The observations made in 1998 and 2000 yielded two complete light curves in each color. The intrinsic color indices indicate that primary component has a temperature of ∼6690 K corresponding to spectral type of ∼F4. The photometric mass ratio of the system was well determined. The corresponding light curves were analyzed by Wilson–Devinney code. From combining the photometric solution with spectroscopic elements, the absolute parameters were determined. Finally, the position of both components in H–R, M–L, and M–R diagrams are given.     

The relative importance of chlorophyll,dissolved and particulate material,and seawater to the vertical extinction of light

The attenuation of light by chlorophyll, particulate and dissolved material, and seawater off the coast of north-west Africa showed distinct cross-shelf variations. Attenuation was most rapid nearshore because of absorption by non-biological particles. This particulate matter was probably aeolian material from the nearby Sahara Desert of resuspended sand from the sediment. Regardless of the source, the marked light extinction resulted in decreased phytoplankton growth nearshore. Light attenuation characteristics of the region were anomalous when compared to those of other ocenic regimes.     

The effect of radiation on seedling growth and physiology in four species of Prosopis L. (Mimosaceae)

Domestication of wild plants needs efforts focused particularly on the development of the theoretical basis of plant responses to environmental conditions. The objective of this study was to assess the effect of radiation on seedling growth and physiology of Prosopis alba, P. chilensis, P. flexuosa and P. glandulosa. Seedlings were grown in a greenhouse and randomly assigned to three light environments: full-sun, 52% sun, and 38% sun. No significant differences were found in the rate of leaf appearance and plant height 60 days after the light treatments began. Instantaneous CO₂uptake was not affected by the light environment during leaf development and did not differ among species. Variations in radiation availability resulted in significant differences in biomass accumulation, shoot/root ratio, protein and total non-structural carbohydrates contents. The practice of shading seedlings reduces the chances of survival ofProsopis due to an increase of the shoot/root ratio and a reduction of total biomass, stored carbohydrates, and the C:N balance.     

The Sponge Community of a Semi-Submerged Mediterranean Cave

Abstract. The sponge fauna of a semi-submerged cave from the Tremiti Archipelago (Adriatic Sea) was studied, and its distribution was analyzed in relation to abiotic (water-movement and light gradients) and biotic (algae and anthozoan substrate cover) ecological factors. Fifty-five species of sponges were recorded. The number of species and the abundance values of sponges increase in the first part of the cave, then progressively decrease, with a sharp fall at the end of the cave. The quick disappearance of algae along the light gradient allows sponges to thrive in the first portion of the cave. The subsequent, progressive decrement of sponges could be the result of food depletion phenomena due to a long persistence of the water body in this long cavity. A high water-turbulence, due to the peculiar morphology of the cave and indicated by the recorded values of water-movement, occurs at the end of the cavity and probably determines the sharp decrement of sponges in the inner portion of the cave. This turbulence may also explain the absence of typical still-water cave species and probably affects the type of development (shape, overgrowth) of the sponges in the community.     

光纤传感腐蚀监测研究

通过化学、物理的方法用金属敏感膜取代光纤的原始包层监测海洋环境中金属结构物的腐蚀状况。通过腐蚀前后光功率的变化表征腐蚀的发生和发展。