南麂列岛红鳍东方鲀网箱养殖试验

1996年7月～1996年12月在南麂列岛进行了红鳍东方网箱养殖试验。结果表明:切齿与否是养殖成活率最主要的影响因素。经2年试验,摸索了红鳍东方TakifuguRubripes养殖从苗种运输、暂养驯化、养成技术、病害防治一整套工艺规范,在自残机理与切齿时间方面有新的见解,并在该鱼养殖中首次在肝脏表面发现明沟线虫ContracaecumRailleetHenry(1912)。     

广西沿海赤潮多发区高浓度氮磷营养元素来源探讨

【目的】探讨广西沿海赤潮多发区氮磷营养元素的来源,分析广西沿海赤潮发生的影响因素,为预防或减少赤潮灾害发生、保护海洋生态环境提供科学依据。【方法】现场调查以钦州湾海域为研究对象,测定表层海水的溶解态氮(DN)、溶解态磷(DP)含量并分析其分布特征,结合历史资料追溯高浓度DN、DP来源及污染物输运过程。【结果】钦州湾内高浓度DN、DP分布区与入海陆源工业污染排放区不一致,离工业污染区近的地方DN、DP浓度偏低,而离工业污染区远的地方DN、DP浓度反而偏高。【结论】广西主要入海河流各类污染物的增加以及不同的海域通过动力途径输送而来的海水可能是广西沿海赤潮多发区的高浓度氮磷营养元素的主要来源。     

涠洲岛西面及西南面沉积物重金属污染分析

【目的】研究广西涠洲岛海域沉积物污染情况并进行分析与评价。【方法】通过分析2014年涠洲岛沉积物重金属元素Cu、Pb、Zn、Cd、Cr含量水平,运用单因子评价法、潜在生态风险指数法和地累积指数法进行污染程度评价。【结果】涠洲岛西面及西南面海域沉积物重金属含量均值从小到大依次为CdCuPbCrZn,分别对应未检出、3.02 mg·kg~(-1)、3.19 mg·kg~(-1)、6.47 mg·kg~(-1)、10.10 mg·kg~(-1),含量范围分别为未检出、0.95~8.29mg·kg~(-1)、2.68~4.07mg·kg~(-1)、1.81~18.46mg·kg~(-1)、ND~34.59mg·kg~(-1)。重金属污染程度属于"低水平",单个及多种重金属生态风险分级均为"轻微",其中Cu是引发生态风险的主要元素,地累积指数亦表明该海域各重金属污染程度均为0级。【结论】总体来说,涠洲岛西面及西南面海域沉积物重金属含量与污染程度较广西沿海其他海域低,仍属清洁水平。     

基于多源卫星资料的太原市城市热岛效应分析

“十五”以来,太原市建成区面积不断扩大,人口数量不断增加,人为活动以及下垫面的变化会影响太原市地表温度的时空分布,城市热岛现象也随之发生变化。为了对太原市今后城市发展及生态文明建设提供科学依据,利用Aqua/MODIS、数字高程、土地利用分类、城市灯光等多源卫星资料计算太原市2003～2019年城市热岛强度和城市热岛比例指数,分析太原市城市热岛效应时空变化特征,并结合高空间分辨率的Landsat8数据分析太原市热岛区和冷岛区下垫面特征。结果表明：2003～2019年,太原市辖区各县（市、区）城市热岛效应较强的月份主要发生在7月～9月,且多在8月城市热岛效应最强,辖区各县（市、区）中小店区城市热岛效应最强;近20年来,太原市辖区各县（市、区）城市热岛强度变化趋势不同,南部的小店区、晋源区和清徐县城市热岛强度整体增加趋势明显且逐渐相连成片,在今后城市发展中应重点关注,北部、东北部和西南部郊区的强冷岛区域的面积增加显著,有效缓解了所在县（市、区）的热岛强度;在城市发展建设中,注意金属、混凝土或塑胶等建筑吸热材料对局部热岛效应的加强作用,可通过大面积水体、植被等缓解局部地区热岛效应。     

海南岛地质构造演化刍论

海南岛大地构造格局及地质构造演化一直是国内外地学界关注的焦点。通过系统调查和对已有资料的综合,提出了海南岛多阶段地质构造演化的新认识。     

千岛湖岛屿马尾松林不同耐阴性植物幼苗动态研究

马尾松林是广泛分布于我国亚热带地区的代表性森林类型,多呈斑块状.马尾松林多处于干扰后森林群落演替的早期阶段,其后期可能演替为本地区的地带性植被-常绿阔叶林.因此,了解斑块生境中马尾松林的更新演替动态,对管理我国亚热带地区森林的物种多样性和生态系统功能具有重要意义.以千岛湖岛屿马尾松林内不耐阴和耐阴植物幼苗的短期动态为研究对象,试图了解片段化斑块生境中马尾松林的更新动态特点.结果发现：在0.5~3.5 a的多个时间尺度上,耐阴植物幼苗的存活能力较不耐阴植物幼苗强,而耐阴植物和不耐阴植物幼苗的补员率和相对生长率并无差异.岛屿面积和岛屿形状指数对于幼苗存活和补员无显著影响.同时,耐阴灌木的幼苗组成中占绝对优势,而其他功能群幼苗比例较低,表明千岛湖岛屿马尾松次生林内耐阴植物更新较不耐阴植物好;岛屿大小和形状对更新群落的短期动态无明显作用;群落更新层的优势功能群为耐阴灌木.结果提示：千岛湖的片段化马尾松林林下层动态的方向性,有利于耐阴植物更新;但在较短时间尺度（≤ 3.5 a）上,片段化斑块的性质对于群落幼苗更新的影响可能较小;耐阴灌木在片段化马尾松林林下层有优势地位.     

Stabilization of tearing mode by current drive

The major disruption limits the operation of present tokamaks. Experimental evidences point out that the growth of tearing modes or the magnetic islands is primarily responsible for the occurrence. Taking the non-inductive current drive effects into account, a set of 3D nonlinear equation is derived. It is shown from simulation that the growth of the magnetic island is suppressed effectively by RF current drive. It is consistent with recent experiments on the HL-1 tokamak in which the plasma is stabilized by an RF current drive.     

改造和提高低产芒果的技术措施

系统地总结了改造和提高低产芒果园的技术措施，为大面积改造低产芒果园提供科学依据．     

Room-temperature SiGe light-emitting diodes

In the present paper the electroluminescence of PIN diodes with either strained SiGe/Si or Ge islands in the i-region has been investigated experimentally and by quantitative modelling. The modelling helped to improve the diode structure. Consequently, diodes with strained Si_0.80Ge_0.20 could be improved so as to reveal emission up to room temperature, if the thickness was high enough. To overcome the thickness limitation due to plastic relaxation, we used selective epitaxy on small areas. We also present results for diodes with Ge islands in the active region. The internal quantum efficiency of light emitting diodes with strained SiGe was at room temperature 10⁻⁴, while diodes with islands emitted ten times less light.     

The use of angle resolved XPS to measure the fractional coverage of high-k dielectric materials on silicon and silicon dioxide surfaces

Angle resolved XPS (ARXPS) is a powerful tool for the determination of the thickness of ultra-thin films. In the case of high-k dielectric layers, the technique is capable of measuring the thickness of both the high-k layer and intermediate layers of silicon dioxide or metal silicate. The values for layer thickness are in close agreement with those generated by a variety of other techniques. As well as knowing the thickness of these layers, it is important to determine whether the layers are continuous or whether the coverage of the high-k layer is only partial. Using ARXPS, a method has been developed to determine whether the coverage of the high-k material is continuous and, if not, to calculate the fraction of the surface that is covered. The method is described with reference to the layers of Al₂O₃ grown on SiO₂ using atomic layer deposition (ALD). The method is then applied to HfO₂ layers produced using ALD on silicon wafers whose surfaces had received three different types of surface treatment. The way in which the layers grow and the nature of the resulting layer were found to depend upon the pre-treatment method. For example, growth on a thermal silicon dioxide surface resulted in complete coverage of HfO₂ after fewer ALD cycles than layers grown on an H-terminated surface. The results from ARXPS are compared with those obtained from ToF SIMS that have been shown earlier to be a valuable alternative to the LEIS analysis [1].