83 resultados para Absalon, abp., 1128-1201.


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Sr2Mg(BO3)(2) thermoluminescence (TL) phosphor was synthesized by a high temperature solid state reaction and the effect of Li+, Bi3+, Gd3+ or Ti4+ as a codopant on TL of Sr2Mg(BO3)(2) : Dy was investigated. The results show that Li+ as a codopant improves the emission intensity of high temperature TL peak of Sr2Mg(BO3)(2) : Dy phosphor whereas the addition of Bi3+, Gd3+ or Ti3+ leads to the decrease of TL intensity. The TL emission bands of Sr2Mg(BO3)(2) : Dy phosphors with Li+, Bi3+, Gd3+ or Ti4+ as a codopant are situated at 480, 579, 662 and 755 nm, which were attributed to the characteristic F-4(9/2)-> H-6(15/2), F-4(9/2)-> H-6(13/2), F-4(9/2)-> H-6(11/2) and F-4(9/2)-> H-6(9/2) transitions of Dy3+ ion, consistent with the emission of Sr2Mg(BO3)(2) : Dy phosphors. The kinetics parameters of 234 degrees C TL peak of Sr2Mg(BO3)(2) Dy-0.04(3+), (Li-0.04(+)) phosphor with the values of trap depth E=1.1 eV, frequency factor s=6.3 x 10(9) s(-1) were estimated by a peak shape method, which obey the second order kinetics.

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Sr2Mg(BO3)(2) thermoluminescence (TL) phosphor was synthesized by a high temperature solid state reaction and the effect of Li+, Bi3+, Gd3+ or Ti4+ as a codopant on TL of Sr2Mg(BO3)(2) : Dy was investigated. The results show that Li+ as a codopant improves the emission intensity of high temperature TL peak of Sr2Mg(BO3)(2) : Dy phosphor whereas the addition of Bi3+, Gd3+ or Ti3+ leads to the decrease of TL intensity. The TL emission bands of Sr2Mg(BO3)(2) : Dy phosphors with Li+, Bi3+, Gd3+ or Ti4+ as a codopant are situated at 480, 579, 662 and 755 nm, which were attributed to the characteristic F-4(9/2)-> H-6(15/2), F-4(9/2)-> H-6(13/2), F-4(9/2)-> H-6(11/2) and F-4(9/2)-> H-6(9/2) transitions of Dy3+ ion, consistent with the emission of Sr2Mg(BO3)(2) : Dy phosphors. The kinetics parameters of 234 degrees C TL peak of Sr2Mg(BO3)(2) Dy-0.04(3+), (Li-0.04(+)) phosphor with the values of trap depth E=1.1 eV, frequency factor s=6.3 x 10(9) s(-1) were estimated by a peak shape method, which obey the second order kinetics.

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Using low-temperature hydrothermal methods, nanoscale lanthanide phenylphosphonates species with different morphologies, namely, nanoparticles and nanorods, have been systematically synthesized. The possible growth mechanism of these nanorods was discussed. X-ray diffraction, transmission electron microscopy, electron diffraction, and photoluminescence spectra were used to characterize these materials. The photoluminescent properties of EU(O3PC6H5)(HO3PC6H5) and La0.91EU0.09(O3PC6H5)(HO3PC6H5) nanorods were discussed.

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A multi-component substitution of Co and Ni was incorporated into ZnTiO3 to form pure hexagonal Zn1-x(Co1/2Ni1/2)xTiO(3) (x = 0,0.8,0.9,1.0) dielectric ceramic powders by a modified sol-gel route, following heat treatments at 600 degrees C for 3 h and at 800 degrees C for 6 h. Differential scanning calorimetry measurements revealed that the order of increasing thermal stability of solid solution compound Zn1-x(Co1/2Ni1/2)(x)TiO3 was ZnTiO3 (945 degrees C), Zn0.1Ni0.9TiO3 (1346 degrees C), Zn-0.1(Co1/2Ni1/2)(0.9)TiO3 (1390 degrees C), and Zn0.1Co0.9TiO3 (> 1400 degrees C). Both the dielectric constant and loss tangent reached a maximum at x = 0.8 and then decreased with solubility, x, and measurement frequency.

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The elucidation of key influence factors for electrostatic adsorption is very important to control protein nonspecific adsorption on modified surfaces. In this study, real-time surface plasmon resonance technique is used to characterize the electrostatic adsorption of two proteins (mouse IgG and protein A) on carboxymethyldextran-modified surface. The results show that protein solution pH and ionic strength are key influence factors for efficient electrostatic adsorption. The influence of protein, solution pH on the amount of electrostatic adsorption depends on the type of the charge and the charge density of both protein and modified matrix on the surface. The electrostatic adsorption process involves a competition between the positively charged protein and other positively charged species in the buffer solution. A decrease of ionic strength leads to an increasing electrostatic adsorption. The kinetic adsorption constants of protein A at different pH values were also calculated and compared.

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规范化管理高科技高效益企业中国科学院成都生物研究所王海燕中共成都市委组织部张松中科院成都生物研究所于1988年开始创办药厂,药厂产值六年翻了六番,原始投资增值数百倍。如今,药厂已更名为地奥制药公司,成为拥有净资产2亿多元、年利税1亿元的集高科技、新产...

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建立了一个氢化物发生-分光光度法同时测定砷、锑、铋的新方法。在酒石酸介质中用KBH_4将 Bi(Ⅲ)、Sb(Ⅲ)、As(Ⅲ)转变成 BiH_3、SbH_3、AsH_3、再分别被乙醇、四氢呋喃、DMF混合溶液(吸收后再加入 HClO_4-DBC-CPA 溶液显色),铁-邻菲罗啉乙醇溶液和 AgNO_3、PVA、乙醇溶液分别吸收。有色溶液在640nm、510nm 和400nm 处有最大吸收。本法简便怏速,灵敏度高。检出限分别是 As 0.04μg/ml、Sb 0.09μg/ml、Bi 0.05μg/ml。用本法对铜、铜合金及沉积物中砷、锑,铋进行测定,结果令人满意。

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A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina. The structure of the new compound was established on the basis of various NMR spectroscopic analyses, including 2D NMR techniques (H-1-H-1 COSY, HMQC, and HMBC) and HR-FAB-MS. This compound displayed moderate antioxidant activity.

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In this study several parameters critical to the success of cryopreserving Sydney rock oyster (Saccostrea glomerata) larvae were investigated. They were: (1) cryoprotectants (10% dimethyl sulfoxide and 10% propylene glycol). (2) freezing protocols (with or without the seeding step). (3) larval concentrations (1,000, 3,000, 5,000, 10,000, 30,000 individuals mL(-1)). and (4) larval ages (6, 12, 24, 48 and 96 h old). The survival rates were determined as percentages of postthaw larvae performing active movements for the 6 and 12 h larvae or active cilia movement for the 24, 48 and 96 h larvae. Analyses showed that the difference in survival rates between different age classses was significant in all the experiments conducted, with the maximum survival rate being achieved in the 24-h-old larvae the postthaw survival rates of larvae cryopreserved with 10% dimethyl sulfoxide (93.1 +/- 0.2%) were significantly higher (P < 0.001) that those with 10% propylene glycol (81.5 +/- 0.4%). Differences in postthaw survival rates between different concentrations (1,000 30,000 individuals mL(-1)) were not significant within each of the three larval age classes (6-, 12-, and 24-h-old ) used.

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本文通过对渤海泥质区不同位置岩芯的粒度、矿物、化学元素等方面的分析,结合浅地层地震剖面、AMS 14C测年、微体古生物分析、稳定同位素测量、古地磁数据等,对全新世渤海泥质区中沉积物物质组成特征、物质来源、形成历史其环境响应进行了探讨。 结果显示,在早全新世期间黄河曾流经渤海南部,其携带泥沙对渤海沉积作用造成一定影响,但不同位置沉积环境及所受黄河影响的大小存在差异。 渤海泥质区的主体部分从约6000 aBP开始形成。当时沉积记录存在突变现象,不仅显示了沉积环境氧化还原条件的改变,而且温度与盐度值的变化以及沉积速率的明显偏高以及浮游有孔虫的出现说明本区开始受到黄海暖流余脉的影响。4500 aBP以来,沉积物中重矿物组合、化学成分等与黄河沉积物已较为接近,说明此时黄河物质对渤海泥质沉积的影响已经占据主导地位。渤海泥质区虽然有着离黄河口较近的特点,但并未出现明显高于陆架其它泥质沉积区的沉积速率,说明受输运机制控制,黄河物质向泥质区的输送量不大,远不如向黄海的输出量。 北部记录着全新世期间发生的两次地磁极漂移,分别发生于2800~3100 aBP(对应Starno事件)和7500~8200 aBP。漂移发生前后,气候、物质来源与海平面均有较大变化,说明地磁极漂移对气候有着重要影响。

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西菲律宾海盆是西太平洋边缘海盆中最古老的海盆之一,从属于菲律宾海板块,研究表明西菲律宾海盆形成过程复杂。 本文对包括KR03-04航次在内的众多航次的海洋重力及磁力调查数据处理,获得了该区域布格重力异常及磁异常等值线图、上下延拓图、导数异常图等常规成果图件。同时,本文还对本单位在该地区所做的多道地震调查中的三条剖面进行了处理和解释,并对其中的两条测线作了重磁震联合反演研究。通过这些工作,本文得出该地区的构造特征。 该区分为冲大东海岭,乌尔达内塔海台及冲绳-吕宋断裂带等次一级的构造单元,总的构造为NWW走向,也有NE向的大构造带。其中,冲绳-吕宋断裂带破碎严重,NE向走向,在琉球海沟附近(126°E)转为NNE向,为一右旋的深大断裂,可能是由于菲律宾海盆受到琉球岛弧阻拦形成的,也可能是一个转换断层;乌尔达内塔海台中部存在一较大的NW断裂。冲大东海岭和乌尔达内塔海台可能是残留的火山弧;结合ODP及DSDP的相关资料,本文确定了琉球海沟外缘俯冲挤压造山带的形成原因及形成年代。在西菲律宾海盆,伏在一层薄薄的沉积物之下有较厚的一层基岩破碎带,这有可能是西菲律宾海盆无岩浆扩张的有力证据之一,此次扩张的动力可能来源于俯冲于琉球岛弧下面板块的拖曳。

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杜仲(Eucommia ulmoides Oliv)叶片的光饱和光合速率为6~10 μmolCO2·m -2·s-1,表观光合量子需要量最低约为17。光合作用的CO2补偿点略大于100μmolCO2·m -2·s-1,属C3型光合作用类型。其光合日变化有明显的中午降低现象,降低的原因除气孔限制外可能还有光抑制等其它因素。光合作用进行时光合产物只有约14% 输出叶片.

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The Rhodiola L. genus (Crassulaceae) is one of the most important medicinal plant products used by Tibetans in Chinese phytotherapy. Fourteen species were examined for their content of salidroside. A considerable quantitative variation was observed using high-performance liquid chromatography and this depended on species and regional factors. It was found that all samples contained salidroside at concentrations ranging between 0.02 mg g(-1) (R. sinuate) and 15.95 mg g(-1) (R. sacra), respectively. The content of salidroside in R. sacra was significantly higher than in other popular medicinal plants of this genus. This finding indicated that there may be more Rhodiola species present in the Qinghai-Tibet Plateau which may be used as a potential source of salidroside.