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铁盐水解法制备铁层柱蒙脱石及其结构特性研究

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矿物岩石地球化学通报 2007年第2期26卷 111-117页

作者：袁鹏杨丹陶奇 fa■za Bergaya 何宏平朱建喜周琴中国科学院广州地球化学研究所 Centrede Recherche sur la Matière Divise CNRS-Universitd'Orlansrue de La FrollerieOrlans Cedex245071

利用低角度X射线衍射、红外光谱、喇曼光谱及孔结构分析,研究了用铁盐水解法制备的铁层柱蒙脱石的结构与性质。所制得的铁层柱蒙脱石以介孔型层离结构为主,微孔型柱撑结构为辅。前者为蒙脱石片层与铁离子水解产生的聚合羟基铁簇合物堆... 详细信息

利用低角度X射线衍射、红外光谱、喇曼光谱及孔结构分析,研究了用铁盐水解法制备的铁层柱蒙脱石的结构与性质。所制得的铁层柱蒙脱石以介孔型层离结构为主,微孔型柱撑结构为辅。前者为蒙脱石片层与铁离子水解产生的聚合羟基铁簇合物堆垛而成的卡房状结构,与d值为6.4±1.0nm的X射线衍射宽峰相对应;微孔型柱撑结构则与d值约1.5nm的(001)衍射峰相对应。所合成的系列铁层柱蒙脱石中最大的比表面积和孔容分别为215.7m2/g和0.291mL/g。500℃热处理后,仍保存铁层柱蒙脱石的介孔结构。铁层柱蒙脱石富含阴离子(NO3-),并作为平衡铁水解聚合物正电荷的反离子而稳定存在,可为磷钨酸离子[PW12O40]3-所交换。铁层柱蒙脱石的新型结构和特殊性质在催化剂、载体与吸附剂等领域具新的应用前景。

关键词：蒙脱石层离结构柱撑结构柱撑粘土

Natural Tubular Halloysite as Drug Carrier: Effect of Organosilane Modification and Thermal Treatment

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矿物学报 2013年第S1期33卷 131-131页

作者： YUAN Peng TAN Daoyong Annabi-Bergaya faza LIU Dong LIU Hongmei CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences University of Chinese Academy of Sciences Centre de Recherche sur la Matière Divisée CNRS-Université d'OrléansOrléans 45071France

Naturally occurring tubular halloysite is a potential drug carrier because of the significant deposit, unique mesoscopic (2-50 nm) or even macroscopic (>50 nm) lumen, and excellent biocompatibility. The drugs loaded on halloysite exhibited slow release under the diffusion limitation by the halloysite nanotube. However, due to the weak interaction between halloysite and guest, the loading capacity of halloysite was relatively low. This drawback severely limits the application of halloysite as carrier in pharmaceutics. In this study, the performance of halloysite as carrier for ibuprofen (IBU) loading was investigated for the first time. The effects of 3-aminopropyltriethoxysilane (APTES) modification and thermal treatment of halloysite on the loading and release of IBU were also studied. The purified halloysites were heated at 120 ℃ and 400 ℃ (labeled as Hal/120 and Hal/400), and then modified with APTES (labeled as Hal/120-A and Hal/400-A). The loading of IBU was achieved by soaking method (labeled as IBU-Hal/120, IBU-Hal/400, IBU-Hal/120-A, and IBU-Hal/400-A.). The in vitro drug delivery assays were performed in phosphate buffer solution. IBU was loaded mainly into the lumen and partially on the external surface of halloysite. The order of IBU contents was as follows: IBU-Hal/400-A (14.8wt%) > IBU-Hal/120-A (12.7wt%) > IBU-Hal/400 (11.8wt%) > IBU-Hal/120 (11.7wt%). The IBU was initially anchored to the surface hydroxyl groups of halloysite by hydrogen bonding, followed by further bonding of IBU with the anchored IBU to form hydrogen-bonded aggregates. The APTES modification of halloysite promoted the loading of IBU by introducing a strong affinity through electrostatic attraction between the introduced aminopropyl groups of APTES and the carboxyl groups of IBU. Thermal treatment at 400°C did not destroy the tubular morphology or the crystal structure of halloysite and had little effect on IBU loading in unmodified halloysite. However, thermal treatment by reducing

关键词： halloysite ibuprofen drug delivery organosilane modification thermal treatment

The Effect of Temperature on Transformation of Kaolinite to Halloysite-like Nanoroll Via One-step Delamination

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矿物学报 2013年第S1期33卷 91-91页

作者： TAN Daoyong YUAN Peng faza Annabi-Bergaya LIU Dong LIU Hongmei Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Centre de Recherche sur la Matière Divisée CNRS-Université d'OrléansOrleansFrance

Tubular halloysite is a hydrated polymorph of kaolinite, commonly considered as its associated mineral. Due to its unique mesoscopic (2–50 nm) tubular structure, it has attracted great interest in the field of adsorption, catalysis, and nanocarrier. The halloysites in different deposits present various morphological properties which significantly affect the interface reactions with functional guests. These scattered properties in addition to their low purity severely limit the actual applications of halloysite in industry.

关键词： kaolinite halloysite-like nanoroll intercalation reaction temperature thermal stability

Evaluation of Seven Function-Known Candidate Genes for their Effects on Improving Drought Resistance of Transgenic Rice under Field Conditions

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Molecular Plant 2009年第1期2卷 73-83页

作者： Ben-Ze Xiao Xi Chen Cheng-Bin Xiang Ning Tang Qi-fa Zhang Li-Zhong Xiong National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University Wuhan 430070 China School of Life Sciences University of Science and Technology of China Hefei 230026 China

Many stress responsive genes have been reported with an effect on improving stress resistance in model plants under greenhouse conditions. Towards identification of genes for drought resistance breeding, seven well documented genes （CBF3, SOS2, NCED2, NPK1, LOSS, zaT10, and NHX1） in stress resistance were selected in this study and transformed into rice cultivar Zhonghua 11 under the control of constitutive promoter Actinl and stress-inducible pro- moter of a rice HVA22 homolog, and transgenic rice were tested for drought resistance under field conditions. A total of 1598 independent transgenic To plants were generated. The percentages of single copy and expression of the transgenes were 36.7% and 57.6%, respectively. For each gene construct, 30 T1 families with expression of transgene were selected for drought resistance testing at the reproductive stage in field, and 10 of them were tested in PVC pipes with a defined stress protocol at the same stage. Relative yield and relative spikelet fertility were used as two major criteria to evaluate drought resistance performance because significantly decreased yield was observed in the T1 generation, Trans- genic families of eight constructs （HVA22P：CBF3, HVA22P：NPK1, Actin 1：LOS5, HVA22P：L OS5, Actin 1：za T10, HVA22P：za T10, Actinl：NHX1, and HVA22P：NHX1） showed significantly higher RY than wild-type （WT） under both drought stress field and PVC tube conditions. Transgenic families of 9 constructs （***2 and CBF3, LOS5, zaT10, and NHX1 by both promoters） showed significantly higher relative spikelet fertility than WT in the field or PVC pipes. In the field drought resistance testing of T2 families derived from the T1 families with relatively lower yield decrease, transgenic families of seven constructs （HVA22P：CBF3, Actinl：NPK1, HVA22P：NPK1, Actinl：LOS5, HVA22P：LOS5, Actin1：zaT10, and HVA22P：zaT10） showed significantly higher yield per plant than WT, and families of nine constructs （Actinl：CBF3, HVA22P：CBF3, HVA22P：-

关键词： Oryza sativa abiotic stress grain yield transformation.

强激光照射对6H-SiC晶体电子特性的影响

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物理学报 2016年第10期65卷 270-278页

作者：邓发明四川民族学院数学系康定626001 四川大学原子与分子物理研究所成都610065

使用基于密度泛函微扰理论的第一性原理赝势法,模拟研究了纤锌矿6H-SiC晶体在强激光照射下电子特性的变化.研究结果表明,电子温度T_e在升高到3.89 eV及以上后,6H-SiC由间接带隙的晶体变为直接带隙的晶体;带隙值随电子温度T_e升高先是增... 详细信息

使用基于密度泛函微扰理论的第一性原理赝势法,模拟研究了纤锌矿6H-SiC晶体在强激光照射下电子特性的变化.研究结果表明,电子温度T_e在升高到3.89 eV及以上后,6H-SiC由间接带隙的晶体变为直接带隙的晶体;带隙值随电子温度T_e升高先是增大后又快速减小,当电子温度T_e大于4.25 eV以后,带隙已经消失而呈现出金属特性.

关键词： 6H-SiC 电子特性激光照射密度泛函微扰理论

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带气囊色努矫形器治疗青少年特发性脊柱侧弯

颈腰痛杂志 2015年第1期36卷 32-35页

作者：苏再发张魁贤泉州市中医院骨科福建泉州362000 福建中医药大学福州350000

目的观察带气囊色努矫形器治疗中度青少年特发性脊柱侧弯(AIS)患者的临床疗效。方法将2012-10-2013-06期间收集的30例中度AIS患者随机分成两组。治疗组15例,采用带气囊的色努矫形器治疗;对照组15例,采用不带气囊的色努矫形器治疗。比较... 详细信息

目的观察带气囊色努矫形器治疗中度青少年特发性脊柱侧弯(AIS)患者的临床疗效。方法将2012-10-2013-06期间收集的30例中度AIS患者随机分成两组。治疗组15例,采用带气囊的色努矫形器治疗;对照组15例,采用不带气囊的色努矫形器治疗。比较两组患者治疗前后主弯的侧弯度数(Cobb angle)和顶椎椎体旋转(AVR)等级,依照2005年SRS年会统一的矫形器治疗脊柱侧弯的有效性标准评价其临床疗效[1]。结果在主弯角度及顶椎椎体旋转度等级改善方面,治疗组优于对照组,且差异有统计学意义(P0.05)。结论与普通色努矫形器相比,采用带气囊的色努矫形器治疗中度AIS可能会更有效的抗脊柱侧弯及抗椎体旋转。

关键词：色努矫形器气囊青少年特发性脊柱侧弯疗效

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气流膨化对苦荞全麦茶品质的影响

湖北农业科学 2013年第16期52卷 3908-3911页

作者：巩发永西昌学院轻化工程学院四川西昌615013

以苦荞(fagopyrum tataricum)米为原料,在0.4~0.8 MPa气压下进行气流膨化,制得苦荞全麦茶样品。通过对比不同样品的感官评价得分、复水率、总黄酮含量、芦丁含量和槲皮素含量,分析气流膨化生产苦荞全麦茶的最好气压条件。结果表明,在0.6... 详细信息

以苦荞(fagopyrum tataricum)米为原料,在0.4~0.8 MPa气压下进行气流膨化,制得苦荞全麦茶样品。通过对比不同样品的感官评价得分、复水率、总黄酮含量、芦丁含量和槲皮素含量,分析气流膨化生产苦荞全麦茶的最好气压条件。结果表明,在0.6 MPa气压下苦荞全麦茶感官评价得分为81.10分、复水率为110.61%、槲皮素含量为0.91%,均为所测定的最高值,其中总黄酮含量为1.46%(干基,以芦丁计)和芦丁含量为0.73%,都处于较高水平;在0.6 MPa气压条件下气流膨化生产苦荞全麦茶综合品质最好。

关键词：苦荞(fagopyrum tataricum)全麦茶气流膨化感官评价

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凉山州苦荞茶总黄酮含量对比及分析

湖北农业科学 2011年第18期50卷 3811-3814页

作者：巩发永西昌学院轻化工程学院四川西昌615013

分析了8个全麦苦荞茶、15个造粒成型苦荞茶、2个苦荞叶芽茶共25个苦荞茶产品的总黄酮含量,结果表明,三类苦荞茶总黄酮含量平均值高低依次是全麦苦荞茶<造粒成型苦荞茶<苦荞叶芽茶,总黄酮含量之比全麦苦荞茶∶造粒成型苦荞茶∶苦荞叶芽茶... 详细信息

分析了8个全麦苦荞茶、15个造粒成型苦荞茶、2个苦荞叶芽茶共25个苦荞茶产品的总黄酮含量,结果表明,三类苦荞茶总黄酮含量平均值高低依次是全麦苦荞茶<造粒成型苦荞茶<苦荞叶芽茶,总黄酮含量之比全麦苦荞茶∶造粒成型苦荞茶∶苦荞叶芽茶为1.00∶2.51∶3.57;同一类型苦荞茶之间总黄酮最高含量平均值和最低含量平均值比值最大的是造粒成型苦荞茶,总黄酮含量差异性最大的是苦荞叶芽茶,其次是造粒成型苦荞茶,最小的是全麦苦荞茶。

关键词：苦荞茶总黄酮凉山

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形符表征数学概念的三种形式

教学与管理 2020年第11期 34-36页

作者：姚建法江苏常州市新北区新桥实验小学

表征数学概念时可以应用丰富的数学化的学具、图像、数学符号等形符元素,并呈现出三个层次:动作性形符表征能让数学概念可感、图像式形符表征能让数学概念可视、符号化形符表征能让数学概念可思。有效转译学生数学思维的表征过程,可以... 详细信息

表征数学概念时可以应用丰富的数学化的学具、图像、数学符号等形符元素,并呈现出三个层次:动作性形符表征能让数学概念可感、图像式形符表征能让数学概念可视、符号化形符表征能让数学概念可思。有效转译学生数学思维的表征过程,可以促进数学概念的深度理解。

关键词：动作性形符图像式形符符号化形符表征数学概念