壳聚糖希夫碱铜配合物的制备及其催化性能     

温燕梅  李思东  钟杰平  谢建英  章超桦 《广东海洋大学学报》2006,26(4):63-66

采用微波辐射加热法使壳聚糖与水杨醛反应生成壳聚糖希夫碱,然后将其与铜盐配位得到壳聚糖希夫碱铜配合物,用UV、FTIR、TG表征产物的结构,并探讨该配合物对过氧化氢分解的催化性能。研究结果表明:壳聚糖希夫碱铜配合物对过氧化氢有良好的催化活性,常温(25℃)常压,pH=7.0的条件下放置12 h,催化H2O2的分解达99.8%,该配合物重复使用3次还保持较好的催化活性。  相似文献   

时空投影法在上海地区梅汛期降水延伸期预报中的应用     

马悦  梁萍  李文铠  何金海 《气象》2018,44(12):1593-1603

本文基于2001—2010年上海市11个基本气象站的逐日降水量和澳大利亚气象局的逐日大气低频振荡(MaddenJulian Oscillation,MJO)指数(包括RMM1和RMM2)资料,选取MJO指数作为预报因子,上海地区梅汛期降水量作为预报对象,建立了基于时空投影法(spatial-temporal projection model,STPM)的上海地区梅汛期降水延伸期预报模型。利用该模型对近6年(2011—2016年)的梅汛期降水进行回报试验,其预报技巧评估结果表明:该模型对未来10～25 d的降水具有较好预报效果,可较准确地预报出梅汛期3/4左右的降水量级和降水发生时段。其中,预报时效为10～20 d的预报技巧较高,而提前21～25 d的预报技巧略有下降。总体而言,基于MJO活动的STPM预报模型在上海地区梅汛期延伸期降水预报中具有较好的参考价值。  相似文献   

Ionizing radiation-induced defects in smectite clays     

D. Gournis  A. E. Mantaka-Marketou  M. A. Karakassides  D. Petridis 《Physics and Chemistry of Minerals》2001,28(4):285-290

 The interaction of γ-rays with smectites induces paramagnetic defects in the structure of these clay minerals. The EPR spectra of three different smectites detect the creation of structural defects and trapping of organic free radicals in the clay structure upon irradiation. The defects are assigned to positive holes or trapped electrons stabilised by existing local charge imbalances in the mineral lattice. The organic radicals are derived from organic compounds present as impurities in the crystal lattice of the clay minerals. In addition, γ-rays cause migration of small interlayer cations (such as Li⁺) into the layers, as clearly evidenced by EPR and FT-IR reflectance spectroscopies. Received: 20 April 2000 / Accepted: 2 December 2000  相似文献   

Impact of the displacement damage in channel and source/drain regions on the DC characteristics degradation in deep-submicron MOSFETs after heavy ion irradiation     

薛守斌  黄如  黄德涛  王思浩  谭斐  王健  安霞  张兴 《海洋学报(英文版)》2010,29(11)

This paper mainly reports the permanent impact of displacement damage induced by heavy-ion strikes on the deep-submicron MOSFETs. Upon the heavy ion track through the device, it can lead to displacement damage, including the vacancies and the interstitials. As the featured size of device scales down, the damage can change the dopant distribution in the channel and source/drain regions through the generation of radiation-induced defects and thus have significant impacts on their electrical characteristics. The measured results show that the radiation-induced damage can cause DC characteristics degradations including the threshold voltage, subthreshold swing, saturation drain current, transconductance, etc. The radiation-induced displacement damage may become the dominant issue while it was the secondary concern for the traditional devices after the heavy ion irradiation. The samples are also irradiated by Co-60 gamma ray for comparison with the heavy ion irradiation results. Corresponding explanations and analysis are discussed.  相似文献   

Tri-frequency spectrum method and results for resolving the parameters of Earth’s liquid core free nutation     

Xiang&#;e Lei  Houze Xu 《中国科学D辑(英文版)》2002,45(4):325-336

The parameters of Earth free core nutation (FCN) are two relatively significant geophysical parameters. Sasao et al. (1980) and Wahr and Bergen (1986) provided the theoretical estimation values of FCN parameters. Gwinn, Herring and Shapiro (1987) first obtained the observational values of FCN parameters by very long base Interference (VLBI) at Cambridge University. In the same year, Neuberg and Zürn in former West Germany and Hinderer in France began to retrieve FCN parameters by the observation of gravity tides and introduced the stacking method. The other scholars who researched into the same geophysical problems by applying the data of gravity tides basically followed the stacking method. The results they reached were similar to the observational result of FCN parameters given by Neuberg et al. in 1987. But the observational results of FCN parameters gained from gravity tides were not identical with those from VLBI, mainly because of the large difference of quality of FCN. So there was not an affirmative observational result of FCN parameters since then. In this paper, The authors firstly introduce the tri-frequency spectrum method with clearly geometrical and geophysical meaning for the resolution of FCN parameters, and the observational results of FCN parameters obtained from tide data at three superconducting gravity stations were accordant with those from VLBI, which will be relatively important to arriving at a certain observational result of FCN parameters.  相似文献   

Tri-frequency spectrum method and results for resolving the parameters of Earth's liquid core free nutation     

雷湘鄂  许厚泽 《中国科学D辑(英文版)》2002,45(4)

The parameters of Earth free core nutation (FCN) are two relatively significant geophysical parameters. Sasao et al. (1980) and Wahr and Bergen (1986) provided the theoretical estimation values of FCN parameters. Gwinn, Herring and Shapiro (1987) first obtained the observational values of FCN parameters by very long base Interference (VLBI) at Cambridge University. In the same year, Neuberg and Zürn in former West Germany and Hinderer in France began to retrieve FCN parameters by the observation of gravity tides and introduced the stacking method. The other scholars who researched into the same geophysical problems by applying the data of gravity tides basically followed the stacking method. The results they reached were similar to the observational result of FCN parameters given by Neuberg et al. in 1987. But the observational results of FCN parameters gained from gravity tides were not identical with those from VLBI, mainly because of the large difference of quality of FCN. So there was not an affirmative observational result of FCN parameters since then. In this paper, The authors firstly introduce the tri-frequency spectrum method with clearly geometrical and geophysical meaning for the resolution of FCN parameters, and the observational results of FCN parameters obtained from tide data at three superconducting gravity stations were accordant with those from VLBI, which will be relatively important to arriving at a certain observational result of FCN parameters.  相似文献   

基于语义模型的地图符号库设计研究   总被引：2，自引：2，他引：0  

胡最  闫浩文 《地理空间信息》2008,6(2):100-102

通过深入分析地图符号的语义扩展和解析地图符号的语言学实体特征,结合地图符号的数学定义,借助转换生成语法规则提出了基于语义的形式化地图符号模型。基于该模型的相关思想方法和面向对象的Visual C^＋＋．NET编程语言设计并开发了地图符号制作工具。  相似文献   

饮用水中三种痕量卤代甲烷的超声辐照处理   总被引：1，自引：0，他引：1  

郭照冰  郑正  郑有飞 《南京气象学院学报》2007,30(5):710-714

以饮用水中痕量氯仿、四氯化碳和一溴二氯甲烷3种卤代甲烷为目标化合物,采用超声辐照技术研究它们在不同条件下的去除效果.结果表明,3种卤代甲烷的超声降解遵循准一级反应动力学模型,超声辐照1 h后的去除效率与速率常数均按氯仿、一溴二氯甲烷、四氯化碳的顺序递增,分子的疏水性对3种卤代甲烷的降解效率有显著影响.超声强度越大,饮用水中的痕量卤代甲烷去除效果越好.超声辐照后自来水的pH值降低很小,进一步论证超声技术应用于饮用水处理的可行性.在敞口容器中,超声波辐照对水样中的卤代甲烷同时存在着降解与吹脱作用,根据超声空化理论,提出可能的超声吹脱机理.  相似文献   

T63动力延伸预报产品在6月气温预测中的解释应用     

白人海 《黑龙江气象》2000,(1):10-12,24

动力气候模式的数值预报产品为局地气候要素的预报提供了一种全新的方法。首先利用ＮＣＥＴ／ＮＣＡＲ再分析资料中的５００ｈＰａ高度对黑龙江省６月发生的气温异常进行诊断分析,对影响的环流形势进行分型,并选取强信号区确定预报因子;在此基础上,利用Ｔ６３动力延伸预报产品进行旬平均气温的相似预报。经实践证明,Ｔ６３动力延伸预报产品在气温异常事件的预报中有一定的应用价值。  相似文献   

海底数字地形模型的空间不确定性分析     

孟婵媛  王晖  李明辉  邹永刚 《海洋测绘》2011,31(3):31-33

分析了格网海底数字地形模型(DTM)对真实海底表达所带来的精度损失,提出了海底DTM的"浅点扩展"原则.试验证明,"浅点扩展"原则能够较好地保证DTM对海底浅点的表达,提高对海底真实地形的表达精度.  相似文献