1978～2008年中国湿地类型变化

分别基于美国陆地卫星(Landsat MSS/TM/ETM+)和中巴资源卫星(CBERS-02B)影像数据,以人工目视解译为主,完成了中国1978～2008年4期(基准年分别为1978,1990,2000和2008年)湿地遥感制图,并进行了大量的室内外验证.在此基础上,对我国湿地现状及近30年来湿地变化进行了初步分析,得到以下主要结论:(ⅰ)截止2008年,中国湿地面积约为324097km2,其中以内陆沼泽(35%)和湖泊湿地(26%)为主.(ⅱ)1978～2008年,中国湿地面积减少了约33%,而人工湿地增加了约122%.过去30年里湿地减少的速度大幅降低,由最初5523km2/a(1978～1990年)降为831km2/a(2000～2008年).(ⅲ)减少的自然湿地(包括滨海湿地和内陆湿地),其类型变化由湿地向非湿地转化的比例逐渐降低.初期(1978～1990年)几乎全部(98%)转换为非湿地;在1990～2000年间减少的自然湿地约有86%转化为非湿地,而在2000～2008年,这一比例下降为77%.(ⅳ)气候变化和农业活动是中国湿地变化的主要驱动因素,湿地变化在中国分为三大不同特征区域,即西部三省/自治区(西藏、新疆和青海)、北部两省/自治区(黑龙江和内蒙古)和其他省市区.其中西部区域尤其是青藏高原,湿地变化的驱动因子以气候增温为主;新疆湿地由于气候增温和农业活动共同作用造成变化不大.北部省/自治区的湿地变化则主要由农业活动引起;而其他省市区的湿地变化几乎完全受控于人类的农业经济活动

Digitized virtual liver and hepatic surgery after filling hepatic duct systems

目的:肝脏管道灌注后进行数字化虚拟肝脏及其手术的研究.方法:用四种颜色的灌注材料对肝脏的四种管道分别进行灌注和固定,然后进行包埋、冰冻和铣切,获取连续肝脏断面图像数据集.再将数据集的图像经配准和分割后在VTK的基础上,使用面绘制和体绘制相结合的方法,进行三维重建和虚拟切割实验.结果:获取肝脏连续肝脏断面图像910张,且四种管道颜色不同.三维重建肝脏模型形态逼真,能随意旋转、放大和缩小,通过设定肝脏及其各管道结构的透明度和颜色能单独或组合显示各结构.并且在模型上能行虚拟肝脏切割实验.结论:不同颜色灌注材料对肝脏管道灌注后铣切获取连续断面数据集有益于肝实质及其内部各管道的识别.以此进行三维重建和虚拟手术的研究,有益于肝脏解剖学和肝脏外科的研究.AIM: To study the digitized virtual liver and hepatic surgery after filling hepatic duct systems. METHODS: Four kinds of intrahepatic ducts were perfused with different filling material ex vivo respectively. And then the samples were used to be frozen, embedded and sliced to obtain serial sectional images. The whole series of hepatic images was employed to reconstruct a 3 dimensional (3D) liver. After the image registration of the tissue sections, the image information of liver parenchyma, hepatic veins, bile duct and cholecyst was obtained by image segmentation, followed by the 3D reconstruction using Visualization ToolKit (VTK) to construct a 3D morphological model of the liver surface and intrahepatic structures. The virtual liver could also be resected at any angle to observe the structure of the resection surface. Furthermore, a Windows PC-based 3D visualized demonstration system and Windows operation system of liver were developed. RESULTS: Total 910 consecutive sectional images of liver were taken. Hepatic arteries, inferior cava veins/hepatic veins, portal veins and biliary ducts were shown with red, blue, green, and yellow colors, respectively. This demostration system of liver provided a graphic user interface to rotate and scale the 3D liver to observe 3D morphological features of the liver and its duct systems by setting the pellucidit and color. A virtual liver simulation system for resection with primary function was established. CONCLUSION: The technique of perfusion of hepatic ducts may be beneficial to identification of intrahepatic structure. And research on digitized virtual liver and virtual hepatic surgery may be beneficial to the development of the hepatic anatomy and surgery.国家自然科学基金(30470493);; 广东省科技计划项目(2003C34303

Preparation and Photocatalytic Properties of ZnO Nanorod Arrays on Ti Substrates

采用两电极体系中恒电流电沉积在Ti基底上制得较均一的ZnO纳米棒阵列，利用SEM和XRD观察表征样品，研究Zn(NO3)2浓度及电流密度对ZnO纳米棒阵列微观形貌的影响. 以甲基橙为目标降解物，考察该电极光催化性能. 结果表明，Zn(NO3)2浓度和电流密度对纳米棒阵列的形貌有显著影响；与ITO玻璃等其他基底相比，在Ti基底上也可沉积较好均一取向的ZnO纳米棒阵列；紫外灯照射下，ZnO/Ti电极对甲基橙（10 mg·L-1）模拟印染废水降解2.5 h，降解率达到83.3%，光催化活性较佳；无光照时ZnO纳米棒的降解率仅7%.In this paper, the uniform ZnO nanorod arrays were prepared by galvanostatic electrodeposition on Ti Substrates. The morphology and structure of samples were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effects of the concentration of Zn(NO3)2 and the deposition current on the morphology of the ZnO nanorod arrays were investigated. Photocatalytic properties of ZnO nanorod arrays were investigated by degradation of methyl orange (MO) under UV-light irradiation. The analysis revealed that the concentration of Zn(NO3)2 and the deposition current strongly influenced the morphology of the ZnO nanorod arrays. Compared with ITO glass substrates and so on, the uniform and preferable oriented ZnO nanorod arrays could be obtained similarly. The photodegradation rate of ZnO/Ti nanorod electrode was 83.3% during the degradation of methyl orange under 2.5 h of irradiation with UV lamp, which shows good photocatalytic activities. However, the photodegradation rate was only 7% without UV-light irradiation.山西省国际科学与技术合作项目(No. 2012081016)资助作者联系地址：太原理工大学化学与化工学院, 山西 太原030024Author's Address: College of Chemistry and Chemical Eegineering, Taiyuan University of Technology, Taiyuan 030024, China通讯作者E-mail：[email protected]

Originality and Vitality

陈耕(厦门市闽南文化研究会常务副会长):闽南语原创歌曲大奖赛分为三个阶段,5月份到7月10日,征集歌词322首入围100首,现在进入音乐创作阶段,将选拔出25首进入决赛,届时还将举办专门的演唱会。举办这次研讨会有两个主题,大陆的闽南语歌曲为何落后?如何提高我们的创作水平。我认为目前我们的闽南语原创歌曲有四个方面的问题:一是作曲重旋律,忽略了编曲(配器);二是样