总量控制模型在河流水质预测中的应用

本文根据卫河实际情况，采用总量控制模型对卫河水质中有机污染指标化学耗氧量（ＣＯＤ）和生化需氧量（ＢＯＤ５）进行了预测，取得了与实际监测数据较为接近的结果，其中ＣＯＤ预测精度达８５％，ＢＯＤ５预测精度则达到了９５％以上。该方法简便直观、易于掌握，具有较强的实用性。     

灰色消解模型的改进——z变换后的线性回归解法

针对文献中提出的灰色消解模型的建模方法进行了ｚ变换，然后改用线性回归的办法求解，实例验证后表明，模拟拟合状况一致，但计算工作量大为减轻。     

Using a Composite Membrane for Enhanced Sensitivity and Faster Response in On-line Membrane Extraction Microtrap Gas Chromatography

On-line membrane extraction microtrap (OLMEM) gas chromatography was used for continuous monitoring of volatile organic compounds (VOCs) in water. The aqueous sample flowed through tubular membrane and the VOCs selectively permeated through it. The permeated VOCs were stripped by a carrier gas and transported to a microtrap. The microtrap retained and concentrated the analytes before injecting into a GC. In this study, the performance of a composite membrane was compared with that of a conventional silicone membrane. The advantages of using the composite membrane were higher extraction efficiency and shorter response time. Extraction efficiencies as high as 95% were obtained for compounds such as toluene and trichloroethane.     

环境预测中的GAM模型

当原始序列属代数曲线型时，应用ＧＡＭ模型可以提高精度，从而避免进行ＧＭ（１，１）模型的残差修正二次建模。从分析ＧＭ（１，１）模型的缺陷着手，结合实例详细介绍了ＧＡＭ模型的思想形成和计算方法。     

The influence of irradiance on the biochemical composition of three phytoplankton species and their nutritional value for larvae of the Pacific Oyster (Crassostrea gigas)

Three species of phytoplankton grown at high (HL) or low light (LL) were fed as saturating rations to laboratory-reared larval Crassostrea gigas. Larval C. gigas fed diets of HL grown Chaetoceros gracilis and HL grown Isochrysis aff. galbana grew faster than those fed LL grown cells of the same phytoplankton species. Faster growth of C. gigas larvae was consistently associated with increases in the percent composition of short chain saturated fatty acids (FA) 14:0+16:0 in the HL grown cells. There were no consistent and significant differences between HL and LL grown phytoplankton cells in their content of carbon, nitrogen, protein, lipid or carbohydrate. Intraspecific increases in percent composition of essential fatty acids (EFAs), 20:53 and 22:63, in the phytoplankton were not associated with improvements in the growth or survival of the oyster larvae. Oyster larvae fed diets of Phaeodactylum tricornutum with a relatively high proportion of EFAs grew more slowly than those fed C. gracilis. In this experiment the proportion of dietary EFA 20:53 was negatively correlated with oyster growth rates. The faster growing oyster larvae contained relatively more of the FAs 14:0+16:0 which may be useful as measures of larval oyster condition. After a diet of one phytoplankton species for ca. 10 d, oyster larvae acquired distinctive FA profiles resembling that of their phytoplankton prey.     

安徽铜陵地区的大隆组

大隆组属岩石地层单位,系指一套灰黑色硅质层、硅质泥岩、页岩夹灰岩的海相沉积。按岩性特征其顶界划在三叠系殷坑组底部黄绿色泥岩或灰白色粘土层之下:其底界以“压煤灰岩”之底为宜。 大隆组上部生物群组合为Pseudotirolites,下部为Anderssonoceras组合,其时代应为吴家坪期至长兴期。     

二氧化硫对棉花叶片光谱反射特性的影响

在动态熏气箱中对棉株进行SO_2处理(2ppm,8小时).测定叶片光谱反射率和微分光谱.受SO_2伤害的棉叶光谱反射率发生变化:在可见光部分,反射率普遍增加;在近红外部分,反射率降低.整个光谱反射曲线发生蓝移,初步确定几个波段可用于区别污染的与正常的棉叶光谱反射特性.     

板材激光弯曲成形数值模拟的研究现状及展望

板材的激光弯曲成形是一种利用高能激光束扫描金属板材表面产生非均匀分布的热应力 ,从而使板材发生塑性变形的金属板材柔性成形新工艺。数值模拟已逐渐成为板材激光弯曲成形研究中的热点内容。综述了近年来国内外对激光弯曲成形过程的温度场及变形场进行数值模拟的研究现状 ,并对其应用范围和发展前景作了展望     

A preliminary study on simplified simulation model of spring wheat growth

In the model developed in this paper, taking the characters and requirements of meteorological services into account, some conventional meteorological observations which are easy to be obtained have been ch.osen, and mathematical equations describing micro-growth processes of crops have been established on the basis of the field experiments, laboratorial analysis and computer's modelling tests with time interval of ten-days for several years (1987-1989), in accordance with the known biological and physical rules and corresponding reference literatures. It is a preliminary simplified simulation model of spring wheat growth in optimal water and nutrient conditions. The field experiments show that simulation results of this simplified model are satisfactory. The potential operational application and theoretical sense are significant in the meteorological forecast of yield and in the assessment of influences of climatic change on agriculture.     

深圳妈湾排海工程非设计条件下海水入侵与冲洗研究

本文从微观的角度，分析了排海工程扩散管内海水入侵与冲洗的临界水力特点，并通过理论分析和物理模型试验的相互验证，得出了上述临界水力条件的判别关系式，提出了判别方法，并由此得到了深圳妈湾排海工程防止海水入侵的临界排放流量和出现海水入侵后的最小冲洗流量，为排海工程在非设计条件下的运行管理提供了依据。