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Influence of La and Nd Complexes with Citric Acid on Cellulase Activity and Its Mechanism

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Journal of Rare earths 2006年第3期 385-385页

作者： Xu Weimin, Wang Li*, Wang Lüfeng, Li Weisong (faculty of Material Science and Chemical Engineering, Institute of Applied Chemistry, Ningbo university, State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo university, Ningbo 3.5{3.1, China)

The influence of La and Nd complexes with citric acid on the cellulase activity for the different cellulose was studied. The La and Nd complexes with citric acid were synthesized by the deposition method. The content of the La and Nd in the complexes was analyzed by the method of EDTA *** complexes were coordinated with the carboxyl of citric acid. The activity of the cellulase, which is the quantity(μg) of gained dextrose from the enough cellulose per mg cellulase per minute, was determined with the DNS method. The results reveal that the La and Nd complexes with citric acid respectively could stimulate the cellulase activity and maximize the activity at 1.0×10 -8 g·L -1 or 1.0×10 -9 g·L -1, which is the concentration of La 3. or Nd 3., for the different cellulose, such as filter paper, CM-Cellulose Na and Cellobiose. The influence of Nd complex on the cellulase activity is stronger than that of La complex.

关键词： rare earth complexes with citric acid cellulase activity cellulose rare earths

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锌和镀锌钢的稀土表面改性

稀土 2003年第5期24卷 52-56页

作者：龙晋明韩夏云杨宁郭忠诚昆明理工大学材料与冶金工程学院云南昆明650093

通过在Ce(NO_3._3.溶液中对锌和电镀锌钢进行化学转化(钝化)处理,在试样表面形成了铈转化膜。利用电子探针显微分析(EPMA)、X射线光电子能谱(XPS)和X射线衍射(XRD)等研究了转化膜的形貌、成分和结构,探讨了锌表面铈转化膜的形成机理。... 详细信息

通过在Ce(NO_3._3.溶液中对锌和电镀锌钢进行化学转化(钝化)处理,在试样表面形成了铈转化膜。利用电子探针显微分析(EPMA)、X射线光电子能谱(XPS)和X射线衍射(XRD)等研究了转化膜的形貌、成分和结构,探讨了锌表面铈转化膜的形成机理。在氯化钠溶液中测定了试样的腐蚀率、极化曲线和电化学交流阻抗谱(EIS)等腐蚀性能参量,并与未钝化和普通铬酸盐钝化试样的情况作了对比。结果表明,本实验得到的锌表面稀土转化膜主要是由CeO_2.Ce_2._3.ZnO组成的复合氧化物膜,铈转化膜的存在阻碍了锌在电化学腐蚀过程中的阴极反应和阳极反应,导致电荷传递电阻增大,腐蚀率降低。在一定条件下,铈转化膜对锌和镀锌钢的肪蚀效果优于铬酸盐转化膜。

关键词：稀土转化膜锌镀锌钢无铬钝化耐蚀性

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微污染水稀土吸附剂动态除磷研究

中国稀土学报 2005年第S2期23卷 121-124页

作者：宁平李彬杨月红张永陈玉保昆明理工大学环境科学与工程学院云南昆明650093

通过浸渍-干燥-焙烧-成型制备了负载稀土镧的沸石-稀土复合新型吸附剂,对去离子水、模拟水、自来水和污水厂出水进行双柱吸附动态深度除磷。结果表明,制备的稀土吸附剂较天然沸石对磷的吸附效率提高数10倍,且污水中常见的正负离子对除... 详细信息

通过浸渍-干燥-焙烧-成型制备了负载稀土镧的沸石-稀土复合新型吸附剂,对去离子水、模拟水、自来水和污水厂出水进行双柱吸附动态深度除磷。结果表明,制备的稀土吸附剂较天然沸石对磷的吸附效率提高数10倍,且污水中常见的正负离子对除磷没有竞争吸附作用。在实际水样含正磷和总磷分别为1.3.和1.3.6 mg.L-1,pH=7.3.流速为6 L.h-1下吸附结果表明,在累积处理量为150 L时出口磷浓度为0.7mg.L-1,仍然有吸附效果。且吸附剂性能稳定,再生10次以上对磷的静态吸附容量仍在12.mg.g-1以上,为微污染深度除磷提供了一条新的可能的途径。

关键词：吸附剂动态除磷吸附稀土

Paleomagnetism of Cretaceous Red beds from Eastern Part of South China Block

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Journal of earth Science 1999年第3期18卷 258-264页

作者： Hayao Morinaga Hiroyuki Kashimura (Department of Global Tectonics, faculty of Science, Himeji Institute ofTechnology, Shosha 2.67, Himeji 671-2.01, Japan)Hiroo Inokuchi(School of Humanity for Environment Policy and Technology, HimejiInstitute of Technolo Department of Global Tectonics Faculty of Science Himeji Institute of Technology Shosha 2167 Himeji 671-2201 Japan School of Humanity for Environment Policy and Technology Himeji Institute of Technology Shinzaike-Honmachi 1-1-12 Himeji 670-0092 Japan faculty of Business Administration Southern Osaka University Hirao 1060-1Mihara-cho Minami-Kawachi-gun 587-8555 Osaka Japan faculty of Science Kobe University Rokkodai-cho 1-1 Nada 657-8501Kobe Japan

We performed on paleomagnetic investigation of the Upper Cretaceous red sandstones collected from Fujiau and Guangdong provinces. Significant characteristic directions were isolated by principal comPonent analysis from 2. of 2. and 9 of 14 sampling sites iu Fujian and Guangdong,respectively. Maximum concentration of global mean directions every province is achieved at 70 %and complete (100 % ) untilting for Fujian and Guangdong, respectively. We regarded these mean directions as the Late Cretaceous paleomagnetic directions and calculated virtual geomagnetic poles (VGPs); Fujian, Lat. /Lon. = 79. 4°N/2.0. 3.E (α95= 5. 1°) and Guangdong, Lat. /Lon. = 80. 1°N/193. 4°E (α95=8. 0°). These two VGPs are nearly equal to each other and to a mean VGP from Sichuan Province reported previously. This observation suggests no relative movement among three regions, Fujian, Guangdong and Sichuan, since the Late Cretaceous. Two VGPs from this study are significantly different from previously reported VGPs from the same regions. Further systematic paleomagnetic works are needed to clarify this difference of VGP Positions.

关键词： Late Cretaceous red sandstone paleomagnetism virtual extrusion tectonics geomagnetic pole South China block (SCB)

稀土元素—铁族金悀非晶态薄膜的磁特性及其应用

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物理学进展 1982年第4期 435-453页

作者：沈德芳 ?井良文中国科学院上海冶金研究所日本大阪大学基础工学部

本文第一部分介绍了Губанов关于非晶态物质具有铁磁性的唯象理论,第二部分介绍近年来有关稀土元素—铁族金属非晶态薄膜的一些研究进展,它包括薄膜的磁、电、磁光等方面的特性,第三部分则介绍这类薄膜的可能应用以及在实验室已... 详细信息

本文第一部分介绍了Губанов关于非晶态物质具有铁磁性的唯象理论,第二部分介绍近年来有关稀土元素—铁族金属非晶态薄膜的一些研究进展,它包括薄膜的磁、电、磁光等方面的特性,第三部分则介绍这类薄膜的可能应用以及在实验室已取得的一些成就。

关键词：非晶态薄膜 RE 磁性金属重稀土钇族元素稀土族 ⅢB族元素磁特性

CATHODIC PROCESS AND WEAR RESISTANCE OF ELECTRO-DEPOSITED RE-Ni-W-P-SiC COMPOSITE COATING

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 369-374页

作者： Z.C.Guo,X.Y.Zhu,R.D.Xu and X.W.Yangfaculty of Material and Metallurgy Engineering, Kunming university of Science and Technology, Kunming650093. ChinaManuscript received 2. December 2.01 in revised form 2. April 2.02 faculty of Material and Metallurgy Engineering Kunming University of Science and Technology Kunming 650093 China

Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-SiC and RE-Ni-W-P-SiC composite coatings. On the contrary, the addition of PTFE in the bath decreases cathodic deposition current density of the coatings. The current density increases a little when the amount of RE is 7-9g/l; however, the current density increases greatly when the amount of RE is increased to 11-13./l. Bui ij the amount of RE is raised further, the current density decreases. Hardness and wear resistance of RE-Ni-W-P-SiC composite coating have been studied, and the results show that the hardness and wear resistance of RE-Ni-W-P-SiC composite coating increase with increasing heat treatment tempera-ture, which reach peak values at 400℃; while the hardness and wear resistance of the coating decrease with the rise of heat treated temperature continuously.

关键词： electrodeposition RE-Ni-W-P-SiC composite coating cathodic process hardness and wear resistance

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杭州附近几种红壤中磁性矿物的分离与鉴定

土壤通报 2000年第5期31卷 196-198页

作者：卢升高俞劲炎浙江大学土化系浙江杭州310029

对杭州附近由第四纪红土、泥岩、石灰岩和花岗岩发育的红壤中磁性矿物进行了研究 .由X -衍射和矿物磁测技术证明四种红壤中的磁性矿物是磁赤铁矿 (γ -Fe2.O3. ,它是红壤磁性的主要贡献者。

关键词：红壤 X-衍射矿物磁测磁赤铁矿

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古代知识分类形式与类书的消亡

商丘师范学院学报 2011年第4期27卷 50-53页

作者：赵汗青北京师范大学教育学部北京100875

类书是古代知识浓缩的资料汇编,是古代知识的概括和集中。它通过知识分类的形式组织以往知识。从古代知识分类思想的渊源,古代造字造词法,"类"字的释义等角度分析古代知识分类思想是感觉相似性分类和主观联想式理解。类书中"天、地、人... 详细信息

类书是古代知识浓缩的资料汇编,是古代知识的概括和集中。它通过知识分类的形式组织以往知识。从古代知识分类思想的渊源,古代造字造词法,"类"字的释义等角度分析古代知识分类思想是感觉相似性分类和主观联想式理解。类书中"天、地、人、事、物"分类形式是古代分类思想的具体体现。在西方近代科学新知识新学科类别的冲击下,类书的知识分类形式越来越不适应新知识体系的要求。这种传统知识分类形式的缺陷是古代类书逐渐消亡的重要原因。

关键词：古代类书知识分类思想渊源

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锌合金表面稀土转化膜的组成与性能研究

昆明理工大学学报（理工版） 2002年第3期27卷 126-129页

作者：龙晋明杨宁陈庆华司云森昆明理工大学材料与冶金工程学院云南昆明650093

通过在铈盐溶液中进行化学转化处理在电池锌合金表面获得了稀土转化膜 .测量了膜的结合强度、在氯化钠溶液中的极化曲线、极化电阻和腐蚀速率 ,利用XPS、XRD和SEM对稀土转化膜的化学成分和组织结构进行了分析 .结果表明 ,稀土转化膜的... 详细信息

通过在铈盐溶液中进行化学转化处理在电池锌合金表面获得了稀土转化膜 .测量了膜的结合强度、在氯化钠溶液中的极化曲线、极化电阻和腐蚀速率 ,利用XPS、XRD和SEM对稀土转化膜的化学成分和组织结构进行了分析 .结果表明 ,稀土转化膜的形成使锌合金的耐蚀性大大提高 ,已达到普通铬酸盐转化膜的耐蚀水平 .稀土转化膜主要由CeO2.、Ce2.O3.ZnO等氧化物组成 .

关键词：锌合金稀土转化膜组成耐蚀性腐蚀表面处理