基于空间群P3对称性的一种新型三维编织材料

用点群S₆ 对应的对称操作推导出一种新的三维编织几何结构单胞. 根据空间群 P3 描述的对称性, 对新的单胞进行对称变换获得了一种新的三维编织几何结构, 研究 了这种三维编织几何结构可行的编织工艺. 通过建立其几何分析模型, 预测了对应三 维编织材料的纤维体积百分含量及其变化趋势.     

The occurrence and significance of C25HBI in Cenozoic saline lacustrine source rocks from the Western Qaidam Basin,NW China

The saline lacustrine deposit of the Oligocene Lower Ganchaigou Formation is the main source rock for the Western Qaidam Basin,NW China.In this study,abundant highly branched isoprenoids with 25 carbon atoms (C25HBI) were detected in the upper section of the Lower Ganchaigou Formation.C25HBI is a biomarker for diatoms,and can provide information regarding biogeochemical processes during production and preservation of sedimentary organic matter.The carbon isotopic values of C25HBI in these source rocks were in the range of-18‰ to-20‰.The relative enrichment in 13C of C25HBI suggests that these isoprenoids were derived from diatom blooms.In this case,the diatoms used HCO3-as an additional carbon source to dissolved CO2 in water column due to their high biological productivity.Conversely,the diatom blooms indicated an abundant nutrient supply to the environment and high primary productivity.Thus,the occurrence of 13C-enriched C25HBI could be an ideal marker for good source rocks.The decreased concentration of CO2(aq) in the water column induced by diatom blooms can result in an enrichment in 13C of organic matter synthesized by primary producers.This may be a possible reason for the occurrence of 13C-enriched organic matter in the Cenozoic source rocks of the Western Qaidam Basin.Previous studies have shown that the high carbon number n-alkanes sourced from diatoms have no carbon preference.Hence,the sources of n-alkanes in regional source rocks are complex,and should be considered when discussing the sources of organic matter in future studies.     

湄洲岛海岸地貌特征及成因研究

湄洲岛海岸地貌的发育受海洋动力和断层活动双重控制。东部以海岸侵蚀为主,形成海蚀崖、海蚀平台、海蚀壕沟等地貌,在岬角间,形成海滩堆积;西部以堆积为主,形成淤泥质海滩,海蚀作用相对比东部弱。东峤断裂控制了台地和丘陵的分布,断裂东盘抬升形成丘陵,西盘下降形成台地。受北西—南东走向的仙游—郊尾断层左行运动影响,湄洲岛北部向西移动,南部向东移动,使岛的轮廓呈＂S＂形态。福建沿海在距今0.7—0.6万年前发生海侵时,湄洲岛处于断块抬升环境,就岛的局地范围,处于低海面;在0.4—0.3万年前福建沿海海侵达到高峰时,湄洲岛的海侵经历了两个阶段,第一阶段为水动型海侵,第二阶段为地动型海侵。     

基于80C196KC单片机的汽车发动机怠速控制系统设计

设计以80C196KC单片机为核心的汽车发动机怠速控制系统,扩展片外存储器和I/O口,增加了通信电路,设计直流电机的驱动电路.采用H桥TLE6209芯片实现了电机的可逆控制.分析发动机怠速工况特点,设计相应的控制策略,试验结果表明基于电控节气门的发动机怠速模糊控制系统,具有良好的动态特性和稳定性,能很好的满足怠速工况控制的要求.     

C60-C60分子对撞的计算机模拟

采用紧束缚方法模拟了两个 Ｃ６０分子对撞的过程,画出了对撞时的分子图形,并给出了不同能量下对撞得到的结果     

部分先验信息Γ下分布族参数的Γ－容许估计

讨论了在某一族先验分布族Γ或者一定的先验矩限制Γ下分布参数的Γ－容许估计，给出了相应的充分条件，分别推广了文献［１］和［２］的结果，并给出了若干例子．     

用BC＋＋设计Windows语言信号处理程序

文章介绍ＢｏｒｌａｎｄＣ~(＋＋)设计Ｗｉｎｄｏｗｓ程序的组成．基于ＯＷＬ类库的界面设计方法和编制语言信号处理程序的特点和开发方法。     

一种新型井下中子发生器

比较了商品氚－钛靶玻璃中子管和自成靶陶瓷中子管的性能，介绍了自成靶陶瓷中子管井下中发生器电路的特点。该中子发生器与阿特拉斯公司的２７２７型Ｃ／Ｏ比测井仪对接成功，开始批量测井。     

决策树学习在RoboCup仿真球队中的应用研究

通过对基于决策树的学习方法的探讨,该文提出了一种用于RoboCup仿真球队中Agent“行为选择能力”的训练算法,使得Agent能够根据当前场上的状态,决定下一步的行动。并以射门为实例,用该方法对Agent进行训练,使Agent学会判断当前状态是否可以射门,在不可射门的情况下选择下一步的行动。     

Self-assembly of N-3-γ-pyridyl Aza[60]fulleroid on Au(111)

Self-assembled monolayers of novel C₆₀ derivative, N-3-γ-pyridyl Aza[60]fulleroid (C₆₀Py), on Au(111) were studied by a scanning tunneling microscope under ultrahigh vacuum (UHV). C₆₀Py molecules were assembled on Au (111) via pyridyl nitrogen-Au interaction. The sole assembly of C₆₀Py molecules on Au (111) only exhibited randoml aggregation of C₆₀Py even the films were annealed at 50 and 105°C. By co-assembling with benzyl mercaptan (BM), the C₆₀PyBM films showed highly dense aggregation, but C₆₀Py assemblies still had disordered structure. After the co-assembled C₆₀Py-BM films were annealed at 50°C, BM molecules were partially desorbed, but the assembly of C₆₀Py remained without obvious change. After the co-assembled C₆₀Py-BM films were further annealed at 105°C, the C₆₀Py monolayers with ordered structure were obtained, while the BM molecules were nearly thoroughly desorbed from the surface. Here, the BM molecules play a key role as a surfactant in the formation of the ordered C₆₀Py monolayer.