中国的红索藻属植物

记述了中国产红索藻属ThoreaBoryemend Necchi的 2种 2变种 ,即棘刺红索藻T hispida (Thorea)Desvauxemend Sheath ,VisetCole ,棘刺红索藻小孢变种T hispidavar microsporaS L XieetZ X Shi,蓝色红索藻T vio laceaBoryemend Sheath ,VisetCole和蓝色红索藻长毛变种T violaceavar longipilosaS L XieetZ X Shi.其中 ,蓝色红索藻T vi

鲂属鱼类形态度量学研究

国家973项目（G2000046801）; 国家自然科学基金49832010

How polluted is the Yangtze River? Water quality downstream from the Three Gorges Dam

The concentrations of major anions and cations, nitrogen and phosphorus, dissolved and particulate trace elements, and organic pollutants were determined for the middle and lower reaches of the Yangtze River (Changjiang) from below the Three Gorges Dam (TGD) to the mouth at Shanghai in November 2006. The concentration of dissolved inorganic phosphate (DIP) was constant at a low level of 6-8 mu gP/L, but the concentration of nitrate (NO3-) approximately doubled downstream and was closely correlated with K+. This translated to a daily load of well over 1000 It of dissolved inorganic nitrogen (DIN) at Datong. The average concentrations of dissolved Pb (0.078 +/- 0.023 mu g/L), Cd (0.024 +/- 0.009 mu g/L), Cr(0.57 +/- 0.09 mu g/L), Cu (1.9 +/- 0.7 mu g/L), and Ni (0.50 +/- 0.49 mu g/L) were comparable with those in other major world rivers, while As (3.3 +/- 1.3 mu g/L) and Zn (1.5 +/- 0.6 mu g/L) were higher by factors of 5.5 and 2.5, respectively. The trace element contents of suspended particles of As (31 +/- 28 mu g/g), Pb (83 +/- 34 mu g/g), and Ni (52 +/- 16 mu g/g) were close to maximum concentrations recommended for rivers by the European Community (EC). The average concentrations of Cd (2.6 +/- 1.6 mu g/g), Cr (185 +/- 102 mu g/g), Cu (115 +/- 106 mu g/g), and Zn (500 +/- 300 mu g/g) exceeded the EC standards by a factor of two, and Hg (4.4 +/- 4.7 mu g/g) by a factor of 4 to 5. Locally occurring peak concentrations exceed these values up to fourfold, among them the notorious elements As, Hg, and Tl. All dissolved and particulate trace element concentrations were higher than estimates made twenty years ago [Zhang, J., Geochemistry of trace metals from Chinese river/estuary systems: an overview. Estuar Coast Shelf Sci 1995; 41: 631-658.]. The enormous loads of anthropogenic pollutants disposed to the river were diluted by the large water discharge of the Yangtze even during the lowest flow resulting in the relatively low concentration levels of trace elements and organic pollutants observed. We estimated loads of e.g. As, Pb and Ni to the East China Sea to be about 4600 kg As d(-1), 3000 kg Pb d(-1), and 2000 kg Ni d(-1). About 6000 t d(-1) of dissolved organic carbon (DOC) was delivered into the sea at the time of our cruise. We tested for 236 organic pollutants, and only the most infamous were found to be barely above detection limits. We estimated that the load of chlorinated compounds, aromatic hydrocarbons, phenols, and PAHs were between 500 and 3500 kg d(-1). We also detected eight herbicides entering the estuary with loads of 5-350 kg d(-1). The pollutant load, even when at low concentrations, are considerable and pose an increasing threat to the health of the East China Sea ecosystem. (c) 2008 Elsevier B.V. All rights reserved.

Fiber Bragg grating hydrophone with high sensitivity

A fiber Bragg grating (FBG) hydrophone with high sensitivity was demonstrated. This hydrophone used a rubber diaphragm and a copper hard core as the sensing element. To compensate the hydrostatic pressure, a capillary tube was fixed at the end of the hydrophone. Theoretical analysis of the acoustic pressure sensitivity was given in this letter. Experiments were carried out to test the frequency response of the hydrophone. The result shows that when the Young's modulus of the diaphragm is higher, a flatter frequency response will be obtained.

A Raman scattering study of GaAs: As films lifted off GaAs substrate

We performed Raman scattering investigations on low-temperature-grown (LTG) films of GaAs that had been lifted off the GaAs substrate. The Raman measurements unambiguously show the effects of excess arsenic on phonon scattering from LTG films of GaAs. The larger downwards shift of the LO phonon frequency for unannealed free-standing films is explained by invoking the elimination of mismatch strain. The Raman signal due to precipitates of elemental arsenic in the annealed GaAs : As films is determined. It is confirmed that the arsenic clusters formed by rapid thermal annealing are mainly amorphous, giving rise a broad Raman peak in the range 180-260 cm(-1).

1.3 mu m high indium content (42.5%) GaInNAs/GaAs quantum wells grown by molecular beam epitaxy

High structural and optical quality 1.3 mu m GaInNAs/GaAs quantum well (QW) samples with 42.5% indium content were successfully grown by molecular beam epitaxy. The growth of well layers was monitored by reflection high-energy electron diffraction (RHEED). Room temperature photoluminescence (PL) peak intensity of the GaIn0.425NAs/GaAs (6 nm / 20 nm) 3QW is higher than, and the full width at half maximum (FWHM) is comparable to, that of In0.425GaAs/GaAs 3QW, indicating improved optical quality due to strain compensation effects by introducing N to the high indium content InGaAs epilayer. The measured (004) X-ray rocking curve shows clear satellite peaks and Pendellosung fringes, suggesting high film uniformity and smooth interfaces. The cross sectional TEM measurements further reveal that there are no structural defects in such high indium content QWs. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Post-WIMP环境下笔式交互范式的研究

提出了一种在Post-WIMP环境下的笔式交互范式:PIBG.PIBG范式采用纸笔隐喻,与WIMP范式相比,承载应用信息的交互组件由Window变为Paper和Frame,用户的交互动作由鼠标的点击变为笔的手势.对PIBG范式中静态的界面形式和动态的交互手势进行了研究和设计.结合认知心理学,从信息呈现和交互方式两个方面对该范式的特点进行了阐述.利用GOMS模型,从界面呈现方式、手势的效率、用户满意度三个方面对该范式进行了心理学评估.从评估结果可以看,PIBG范式通过模拟日常纸笔环境,利用用户原有的知识,可以明显地减轻认知负担,提高操作效率.

海底沉积物样品声衰减与温度关系的实验研究

不同海区海水温度不同，导致不同海区沉积物温度不同；实验室环境温度变化

Tunnel Junction AlGaInP Light Emitting Diode

The n-type GaAs substrates are used and their conductive type is changed to p-type by tunnel junction for AlGaInP light emitting diodes (TJ-LED), then n-type GaP layer is used as current spreading layer. Because resistivity of the n-type GaP is lower than that of p-type, the effect of current spreading layer is enhanced and the light extraction efficiency is increased by the n-type GaP current spreading layer. For TJ-LED with 3μm n-type GaP current spreading layer, experimental results show that compared with conventional LED with p-type GaP current spreading layer, light output power is increased for 50% at 20mA and for 66.7% at 100mA.

GaAs/AlAs脊形量子线的光学研究

利用分子束外延技术，在GaAs两个(113)晶面的脊形交接处制备了量子线。在低温PL谱上，观测到量子线的发光峰。通过微区、变温和偏振的发光测量，证实了量子限制效就和一维量子线在上述结构中的存在。

InAs/GaAs自组织生长量子点结构中浸润层光致发光研究

当激发光能量小于GaAs热垒带边能量时，在InAs量子点结构中，清楚地观察到与InAs浸润层有关的发光峰。研究表明，此发光峰主要来源于浸润层中局域态激子发光，局域化能量为12meV,发光具有二维特性。在相同的生长条件下，此发光峰位置与InAs层的厚度基本无关。这些结果有助于进一步深入研究浸润层的形貌和光学性质。