Sulfur and carbon isotopic variations in Neoproterozoic sedimentary rocks from southern China

A new set of δ34Ssulfide, δ34Ssulfate and δ13Ccarbonate values has been reported from Neoproterozoic sedimentary rocks in southern China. The interglacial black shales of the Datangpo Fm. display higher δ34Ssulfide values with >+20‰ average, but the postglacial black shales from the Doushantuo Fm. show negative δ34Ssulfide values. However, the Jinjiadong Fm., the same post-glaciation as the Doushantuo Fm., has positive δ34Ssulfide values, implying that the δ34S value of sedimentary sulfides would be controlled by lithofacies and paleogeographic environments. The δ34Ssulfate values relative to δ13Ccarbonate were obtained by extraction of trace sulfate from the successive carbonate sequences in the Yangtze Gorges sections. A preliminary interpretation suggests that the oceanic environment may fluctuate dramatically at the post-glacial Doushantuo stage and, then, recover its stability at the Dengying stage on the basis of the high resolution δ34S and δ13C curves of seawater.     

不同药物对革胡子鲶幼苗隐鞭虫病治疗的初步研究

本文报道了不同药物对革胡子鲶幼苗隐鞭虫病疗效的研究，较为详细地阐述了氯化钠、重铬酸钾、高锰酸钾、硫酸铜、硫酸亚铁、孔雀石绿、亚甲基兰和甲醛等药物对隐鞭虫的治疗效果及其对革胡子鲶幼苗成活率的影响。对治疗革胡子鲶幼苗隐鞭虫病选择最佳药物及其安全浓度具有一定的理想和实践意义。     

间羧基偶氮羧与钡显色反应的研究

研究了显色剂间羧基偶氮羧（ｍｅ－ｃ）与Ｂａ２＋的显色反应，在ｐＨ值为３．０的缓冲溶液中，Ｂａ２＋与间羧基偶氮羧（ｍｅ－ｃ）在λ＝７０５ｎｍ形成β型配合物，ε７０５＝１．２×１０５Ｌ／ｍｏｌ·ｃｍ．该显色反应可用于痕量Ｂａ２＋的分析，具有很高的灵敏性．     

并行设计过程的一种矩阵规划方法

利用信息论中的香农熵对信息流进行度量，建立了模糊设计结构的矩阵。通过分解和割裂算法对该矩阵进行重构，揭示了并行设计过程的内部结构，经过重新组织后的设计过程为并行设计的管理，控制，实验提供了新的策略。     

Adaptive learning algorithm based on mixture Gaussian background

The key problem of the adaptive mixture background model is that the parameters can adaptively change according to the input data. To address the problem, a new method is proposed. Firstly, the recursive equations are inferred based on the maximum likelihood rule. Secondly, the forgetting factor and learning rate factor are redefined, and their still more general formulations are obtained by analyzing their practical functions. Lastly, the convergence of the proposed algorithm is proved to enable the estimation converge to a local maximum of the data likelihood function according to the stochastic approximation theory. The experiments show that the proposed learning algorithm excels the formers both in converging rate and accuracy.     

大型组培苗生产实验装置的研究

阐述了一大型的组培苗生产实验装置及环境测控系统,该装置能对温度、空气湿度、光照强度、CO2浓度、空气流速和营养液pH值等环境因子通过一套计算机控制系统进行自动检测及控制或直接进行人工调控.     

3004铝的动态力学性能及本构模型

为了得到3004铝的动态力学性能及本构模型,运用静态实验机和分离式Hopkinson压杆动态加载装置,在温度为10～400℃、应变率为0.000 5～2 000s-1范围内得到了3004铝在准静态拉伸及动态压缩条件下的应力-应变曲线,并基于Johnson-Cook材料模型对其进行拟合分析.结果表明:3004铝有明显的应变率强化效应和温度软化效应,其应力随应变率的增加而增加,随温度的升高而降低;拟合得到的3004铝动态本构关系曲线可以描述出材料在大应变率和高温下的力学性能.     

具有非单调发病率传染病模型解的存在唯一性

利用上、下解方法及相应的单调迭代方法研究了一类具有非单调发病率的传染病模型,获得了解的存在唯一性.     

判别分析在土壤资源质量评价中的应用——以怀远县为例

本文试用判别分析法,利用计算机对怀远县土壤资源进行评价。选用12个典型土种,9个变量(即评价项目),并进行数字化。经多变量判别分析后,8个变量被入选而有效。然后选取最佳参数建立判别模式,对未知归属的土种进行判别归类,对典型土种的等级进行验证或适当调整。判别结果与经验评价分类完全一致。