984 resultados para Drouet, Juliette, 1806-1883.


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By fusing an electron-deficient ring system with the phenyl ring of a 2-phenylpyridine (ppy)-type ligand, a new and synthetically versatile strategy for the phosphorescence color tuning of cyclometalated iridium(III) and platinum(II) metallophosphors has been established. Two robust red electrophosphors with enhanced electron-injection/electron-transporting features were prepared by using an electron-trapping fluoren-9-one chromophore in the ligand design. The thermal, photophysical, redox and electrophosphorescent properties of these complexes are reported. These exciting results can be attributed to a switch of the metal-to-ligand charge-transfer (MLCT) character of the transition from the pyridyl groups in the traditional Ir-III or Pt-II ppy-type complexes to the electron-deficient ring core, and the spectral assignments corroborate well with the electrochemical data as well as the timedependent density functional theory (TD-DFT) calculations. The electron-withdrawing character of the fused ring results in much more stable MLCT states, inducing a substantial red-shift of the triplet emission energy from yellow to red for the Ir-III complex and even green to red for the PtII counterpart.

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A novel biodegradable amphiphilic block copolymer PLGG-PEG-PLGG bearing pendant glucose residues is successfully prepared by the coupling reaction of 3-(2-aminoethylthio) propyl-R-D-glucopyranoside with the pendant carboxyl groups of PLGG-PEG-PLGG in the presence of N,N'-carbonyldiimidazole. The polymer PLGG-PEG-PLGG, i.e., poly {(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}-block-poly(ethylene glycol)-block-poly{( lactic acid)-co-[( glycolic acid)-alt-(L-glutamic acid)]}, is prepared by ring-opening copolymerization of L-lactide (LLA) with (3s)-benzoxylcarbonylethylmorpholine-2,5-dione (BEMD) in the presence of dihydroxyl PEG with molecular weight of 2000 as macroinitiator and Sn(Oct)(2) as catalyst, and then by catalytic hydrogenation. The glucose-grafted copolymer shows a lower degree of cytotoxicity to ECV-304 cells and improved specific recognition and binding with Concanavalin A (Con A). Therefore, this kind of glucose-grafted copolymer may find biomedical applications.

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分别以亚铁氰化钾和现场所产生的二茂铁阳离子(Fc+)作为冰相和有机相的电活性物质,应用扫描电化学显微镜(SECM)和微电极技术研究了在低温条件下冰/1,2-二氯乙烷界面上的电子转移反应.选择合适的共同离子四丁基铵阳离子(TBA+)来控制界面电位,利用SECM得到的正、负反馈信息,研究了不同温度下界面电位差驱动的液/液界面上的电子转移反应,并通过拟合实验和理论数据得到了此异相界面电子反应速率常数等.实验结果验证了此反应动力学常数是由界面电位差所决定的.在相变的温度时,电子转移反应速率常数有一个大的改变,实验结果反映了相变的过程.

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The sodium ion transfer across the micro-water/1,2-dichloroethane interface facilitated by a novel ionophore, liquid crystal crown ether was studied systematically. The sodium ion transfer facilitated by LCCE is controlled by diffusion studied by cyclic voltammetry. The diffusion coefficient of LCCE in 1,2-dichloroethane was calculated to be equal to (2.61 +/- 0.12) X 10(-6) cm(2)/s and the stability constant of the complex between Na+ and LCCE was determined as lg beta (o) = 5.7 in 1,2-dichloroethane.

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用循环伏安法研究新型载体端烯基液晶冠醚推动钠离子的转移 ,结果表明 ,钠离子的转移由扩散控制 .探讨了影响钠离子转移的因素 ,如端烯基液晶冠醚和钠离子的浓度等 .求算出端烯基液晶冠醚在 1 ,2 -二氯乙烷中的扩散系数为 ( 2 .6 1± 0 .1 2 )× 1 0 - 6cm2 /s,端烯基液晶冠醚和钠离子在 1 ,2 -二氯乙烷中所形成的配合物稳定常数 lgβo=5 .7

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The complexes of Ln(L-Pro)s(H2O)2(ClO4)3(Ln = Pr, Nd and Er. L-Pro = L-Proline) were synthesized and characterized by elemental analysis, IR. spectra and thermal analysis. The singal crystal Pr2(L-Pro)6(H2O)4(ClO4)6 Was also obtained. The crystal belongs to monoclinic, P2(1), a = 0.9879 (3) nm, b = 2.1883 (4) nm, c = 1.3393 (2)nm, beta = 91.23(2)-degrees, V = 2.895(1) nm3, Z = 2. R = 0.035 for 5032 observed reflections. The coordination polyhedron of Pr(III) ion comprises six oxygen atoms from L-Pro molecules and two water molecules. Each L-Pro molecule coordinates to two Pr(III) ions through its carboxyl group which serves as a bridging bidentate ligand to form onedimensional chain structure.

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本文合成了通式为Ln(L-Pro)_3(H_2O)_2(ClO_4)_3(Ln=Pr、Nd、Er,L-Pro=L-脯氨酸)的固体配合物.元素分析、红外光谱、热分析对配合物进行了表征.培养了镨脯氨酸配合物的单晶,X射线四圓衍射确定了晶体的结构.晶体属于单斜晶系、空间群P2_1,α=0.9879(3),b=2.1883(4),c=1.3393(2)nm,β=91.23(2)°,V=2.895(1)nm~3,Z=2.晶体中每一个镨原子与来自6个L-脯氨酸羧基上的6个氧原子和2个结晶水分子键合,形成了一个八配位的稍有畸变的三角十二面体.每一个L-脯氨酸分子以羧基双齿方式与两个镨离子配位,形成了一个无限长的链状结构.

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C12H12I2Te4, M(r) = 920.44, monoclinic, P2(1)/n, a = 10.942 (2), b = 14.924 (2), c = 11.415 (2) angstrom, beta = 104.32 (1)-degrees, V = 1806.0 (5) angstrom 3, Z = 4, D(x) = 3.38 g cm-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 100.7 cm-1, F(000) = 1592, T = 294 K, R = 0.033 for 1828 observed reflections. One of the Te atoms is bonded to the two I atoms, which are on either side of the molecular plane. The Te-I distances are 2.963 (1) and 2.961 (1) angstrom, which means oxidation at the Te atom instead of at the C = C bonds.

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The biosynthesis of glycolipids in E. fasciculatus was studied by C-14 label and chase. The fatty acids in sulphoquinovosyl diacylglycerol (SQDG) were almost 16-carbon and 18-carbon ones. In addition to the two fatty acids, monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG) contained 8.5 mol% and 31.0 mol% of eicosapentaenoic acid (20 : 5), respectively, and this fatty acid was usually distributed in the sn-1 position of the glycerol backbone. When plants were incubated with [2-C-14] acetate, differences existed in the positional distribution of the labeled fatty acids in sn-1 and sn-2 among the three glycerolipids. In SQDG C-14-labeled fatty acids were distributed uniformly in the sn-1 and sn-2 positions. In DGDG, C-14-labeled fatty acids were mainly distributed in the sn-2 position. In MGDG, the radioactivity of fatty acids in sn-1 position was far greater than that in sn-2 position after a 30 min pulse label, and the difference in radioactivity between the two positions decreased rapidly. The above results indicated that differences in the positional distribution of C-14-labeled fatty acids between sn-1 and sn-2 positions might be related to 20 : 5 and the biosynthesis of DGDG. Our results also suggested that E. fasciculatus had the same DGDG biosynthetic pathway as that in higher plants and galactosyl transferase was selective for MGDC.

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Thermal analysis and thermolysis kinetics of three kinds of seaweeds and fir wood (M. glyptostriboides Huet Cheng), a kind of typical land plant, had been conducted. The results showed that thermal stability follows the order of Grateloupia filicina < Ulva lactuca < Dictyopteris divaricata < fir wood. A notable difference on heat flow between seaweeds and fir wood during thermolysis was that the former were mainly connected with exothermic processes at relatively lower temperature regimes. while the latter was connected with an apparent endotherm at a relatively higher temperature regime followed by a maximum exothermic peak. This suggested that the heat coupling might be realized if co-thermolysis of seaweeds and fir wood were carried out. The main devolatilization phase of each seaweed could be described by Avrami-Erofeev equation, which indicated that thermolysis of seaweeds follows the mechanism of random nucleation and nuclei growth, whereas that of fir wood by Z-L-T equation and its thermolysis mechanism was three-dimensional diffusion. The activation energies calculated for both seaweeds and fir wood increase as conversion increases. However, those for the former have wider distribution. (c) 2006 Elsevier Ltd. All rights reserved.

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异毛虫科(Paraonidae)和海稚虫科(Spionidae)是环节动物门(Annelida),多毛纲(Polychaeta)中两个常见的科,其成体在海洋生态系统尤其是海洋底栖动物群落中占有重要地位。中国近海异毛虫科和海稚虫科种类极为常见,在潮间带和潮下带均有分布。但由于此两科种类个体小,采集和鉴定困难,在中国一直没有系统的分类学研究。 本论文选择异毛虫科和海稚虫科为研究对象,以中国科学院海洋研究所海洋生物标本馆馆藏的3000余号成体标本为主要研究材料,结合攻读博士学位期间对全国各海域的补充采集标本和从其它单位借用的标本,在认真阅读相关文献和比对某些种类模式标本的基础上,首次对此两科的中国种类进行了全面系统的分类学和地理分布研究。结果如下: 1. 本文记述了中国海域异毛虫科4属18种,其中包括3新纪录种;海稚虫科16属39种,包括7新种,10新纪录种。各鉴定种类均进行了详细的分类学特征描述,并附有形态学结构图。对罕见种类的标本和保存状况较差、光学显微镜无法获得可靠分类学信息的标本进行了扫描电镜观察,并拍摄有电镜照片。 2. 对中国海域有关异毛虫科和海稚虫科种类记录进行了系统的分类学修订,澄清了部分种类特别是一些常见种类分类学研究中存在的错误和混淆。(1)通过大量阅读文献和反复比较检查标本,认为以前我国文献记录的海稚虫科奇异稚齿虫属的奇异稚齿虫Paraprionospio pinnata (Ehlers, 1901)实际包括3种,即扭鳃奇异稚齿虫Paraprionospio inaequibranchia (Caullery, 1914)、枫香树奇异稚齿虫Paraprionospio coora Wilson, 1990和冠奇异稚齿虫Paraprionospio cristata sp. nov.,其中扭鳃奇异稚齿虫和枫香树奇异稚齿虫在中国海属首次记录,冠奇异稚齿虫为一新种。枫香树奇异稚齿虫主要分布于黄海,其分布南界为121°30′ E, 34°30′ N, 扭鳃奇异稚齿虫分布于南海,其分布北界为114°00′ E, 21°45′ N,冠奇异稚齿虫分布区域较广,从长江口到南海的沿岸水域均有分布。奇异稚齿虫是分布在智利、南加利福尼亚、西墨西哥(可能还有安哥拉)的种,在我国海域未见分布。(2)将在我国北方沿海非常常见但长期被记录为鳞腹钩虫Scolelepis (Scolelepis) squamata (Müller, 1806)(海稚虫科)的标本重新鉴定为一个新种,即红纹腹钩虫Scolelepis (Scolelepis) daphoinos sp. nov.;鳞腹钩虫分布于北大西洋和地中海沿岸水域,在我国海域未见分布。(3)明确了中国海Prionospio steenstrupi复合体种类。此复合体所包含的种类在形态上十分相似,分类学研究时极易混淆。在已有的文献记录中,该复合体中国种类包括两种,玛氏稚齿虫Prionospio (Prionospio) malmgreni Claparède, 1870和西沙稚齿虫Prionospio (Prionospio) sishaensis Wu & Chen, 1964。本文将该复合体中国种类修正为5种,分别是包氏稚齿虫Prionospio (Prionospio) bocki Söderström, 1920、开普敦稚齿虫Prionospio (Prionospio) dubia Maciolek, 1985、太平洋稚齿虫Prionospio (Prionospio) pacifica sp. nov.、欢乐稚齿虫Prionospio (Prionospio) paradisea Imajima, 1990和西沙稚齿虫Prionospio (Prionospio) sishaensis Wu & Chen, 1964。现在大多数分类学者认为玛氏稚齿虫是一个不可鉴定种,该种的原始描述可能包括数种,且模式标本已丢失。(4)将中国海记录的矮小离稚齿虫Apoprionospio pygmaea (Hartman, 1961)更正为卡米拉离稚齿虫Apoprionospio kirrae Wilson, 1990;将中国海记录的科氏光稚虫Spiophane kroyeri Grube, 1860更正为深蓝光稚虫Spiophanes fuscatus sp. nov.。 3. 比较研究了中国海域异毛虫科和海稚虫科的区系特点,详细分析了两科中国海种类的组成。认为中国种类在区系组成上属于印度-马来区系,异毛虫科中国海特有种较少,仅2种,占该科中国种数的11%;而海稚虫科中国海特有种较多,共9种,占该科中国种数的23%。中国海异毛虫科种类组成和日本、俄罗斯附近水域的组成较为相似,中国海海稚虫科种类组成和日本、澳大利亚附近水域的组成较为相似。

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A new species of Spionidae, Scolelepis (Scolelepis) daphoinos sp. nov., is described and illustrated from northern China seas. The species was frequently encountered and highly abundant on sand beaches, but rarely found in subtidal areas. It was formerly misidentified as S. (S.) squamata (Muller, 1806) in China but differed from the latter species in several details in morphology, including the presence of obvious reddish pigmentation patches and the absence of unidentate hooded hooks. Another two Scolelepis species, S. (S.) lingulata Imajima, 1992 and S. (S.) variegata Imajima, 1992, are reported for the first time from Chinese waters. Two species of Scolelepis, S. (S.) globosa Wu & Chen, 1964 and S. (S.) lefebvrei (Gravier, 1905), were reported previously; therefore, five species in this genus are known from China in total. A key to all Scolelepis species from Chinese waters is provided.

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Seven new sesquiterpenes (1-7), together with seven known sesquiterpenes, aplysin (8), aplysinol (9), gossonorol (10), 7,10-epoxy-ar-bisabol-11-ol (11), 10-epi-7,10-epoxy-ar-bisabol-11-ol (12), johnstonol (13), and laurebiphenyl (14), have been isolated from the red alga Laurencia tristicha. The structures of new compounds were established as laur-11-en-2,10-diol (1), laur-11-en-10-ol (2), laur-11-en-1,10-diol (3), 4-bromo-1,10-epoxylaur-11-ene (4), cyclolauren-2-ol (5), laurentristich-4-ol (6), and ar-bisabol-9-en-7,11-diol (7) by means of spectroscopic methods including IR, HRMS, and ID and 21) NMR techniques. Compound 6 possessed a novel rearranged skeleton. All compounds were tested against several human cancer cell lines including lung adenocarcinoma (A549), stomach cancer (BGC-823), hepatoma (Bel 7402), colon cancer (HCT-8), and HELA cell lines. Laurebiphenyl (14) showed moderate cytotoxicity against all tested cell lines, with IC50 values of 1.68, 1.22, 1.91, 1.77, and 1.61 mu g/mL, respectively. Other compounds were inactive (IC50 > 10 mu g/mL).