973 resultados para 1,2,3,4-TetraClBz max


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Emmotin-H, a naturally occurring sesquiterpenoid 1,2-naphthoquinone pigment (1) has been synthesised in a four step sequence starting from the known 5,8-dimethyl-4-oxotetralin-2-carboxylic acid (3a). Selenium dioxide oxidation of its methyl ester (3b) gives 3-methoxycarbonyl-5,8-dimethyl-1,2-naphthoquinone (4) which on reductive acetylation affords the corresponding diacetoxynaphthalene ester (5). Its reaction with excess of methylmagnesium iodide is accompanied by aerial oxidation during work-up and furnishes emmotin-H (1).

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Novel pyrroloisoquinolines 4 are obtained from 1-methyl-3,4-dihydroisoquinolines 1 by the action of POCl3 and DMF, along with the expected mono- and dialdehydes 2 and 3 respectively and also directly from N-acetyl-2-phenethylamines.

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Lead magnesium niobate-lead titanate (PMN-PT) is an intriguing candidate for applications in many electronic devices such as multi-layer capacitors, electro-mechanical transducers etc. because of its high dielectric constant, low dielectric loss and high strain near the Curie temperature. As an extension of our previous work on Ta-doped PMNT-PT aimed at optimizing the performance and reducing the cost, this paper focuses on the effect of Pb volatilization on the dielectric properties of 0.77Pb(Mg1/3(Nb0.9Ta0.1)2/3)O3-0.23PbTiO3. The dielectric constant and loss of the samples are measured at different frequencies and different temperatures. The phase purity of this compound is determined by X-ray diffraction pattern. It is found that the volatilization during sintering does influence the phase formation and dielectric properties. The best condition is sintering with 0.5 g extra PbO around a 4 g PMNT-PT sample.

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The ir absorption of gaseous 15NH3 between 510 and 3040 cm−1 was recorded with a resolution of 0.06 cm−1. The ν2, 2ν2, 3ν2, ν4, and ν2 + ν4 bands were measured and analyzed on the basis of the vibration-rotation Hamiltonian developed by V. Špirko, J. M. R. Stone, and D. Papoušek (J. Mol. Spectrosc. 60, 159–178 (1976)). A set of effective molecular parameters for the ν2 = 1, 2, 3 states was derived, which reproduced the transition frequencies within the accuracy of the experimental measurements. For ν4 and ν2 + ν4 bands the standard deviation of the calculated spectrum is about four times larger than the measurements accuracy: a similar result was found for ν4 in 14NH3 by Š. Urban et al. (J. Mol. Spectrosc. 79, 455–495 (1980)). This result suggests that the present treatment takes into account only the most significant part of the rovibration interaction in the doubly degenerate vibrational states of ammonia.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This data set contains soil carbon measurements (Organic carbon, inorganic carbon, and total carbon; all measured in dried soil samples) from the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. Stratified soil sampling to a depth of 1 m was repeated in April 2007 (as had been done before sowing in April 2002). Three independent samples per plot were taken of all plots in block 2 using a motor-driven soil column cylinder (Cobra, Eijkelkamp, 8.3 cm in diameter). Soil samples were dried at 40°C and segmented to a depth resolution of 5 cm giving 20 depth subsamples per core. All samples were analyzed independently. All soil samples were passed through a sieve with a mesh size of 2 mm. Because of much higher proportions of roots in the soil, the samples in 2007 were further sieved to 1 mm according to common root removal methods. No additional mineral particles were removed by this procedure. Total carbon concentration was analyzed on ball-milled subsamples (time 4 min, frequency 30 s**-1) by an elemental analyzer at 1150°C (Elementaranalysator vario Max CN; Elementar Analysensysteme GmbH, Hanau, Germany). We measured inorganic carbon concentration by elemental analysis at 1150°C after removal of organic carbon for 16 h at 450°C in a muffle furnace. Organic carbon concentration was calculated as the difference between both measurements of total and inorganic carbon.

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This data set contains soil carbon measurements (Organic carbon, inorganic carbon, and total carbon; all measured in dried soil samples) from the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. Stratified soil sampling to a depth of 1 m was performed before sowing in April 2002. Three independent samples per plot were taken of all plots in block 2 using a motor-driven soil column cylinder (Cobra, Eijkelkamp, 8.3 cm in diameter). Soil samples were dried at 40°C and segmented to a depth resolution of 5 cm giving 20 depth subsamples per core. All samples were analyzed independently. All soil samples were passed through a sieve with a mesh size of 2 mm. Rarely present visible plant remains were removed using tweezers. Total carbon concentration was analyzed on ball-milled subsamples (time 4 min, frequency 30 s**-1) by an elemental analyzer at 1150°C (Elementaranalysator vario Max CN; Elementar Analysensysteme GmbH, Hanau, Germany). We measured inorganic carbon concentration by elemental analysis at 1150°C after removal of organic carbon for 16 h at 450°C in a muffle furnace. Organic carbon concentration was calculated as the difference between both measurements of total and inorganic carbon.

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INTRODUCTION: Galectin family members have been demonstrated to be abnormally expressed in cancer at the protein and mRNA level. This study investigated the levels of galectin proteins and mRNA expression in a large cohort of patients with papillary thyroid carcinoma and matched lymph node metastases with particular emphasis on galectin-1 and galectin-3. METHODS: mRNA expression of galectin family members (1, 2, 3, 4, 7, 8, 9, 10 and 12) were analysed by real-time polymerase chain reaction in 65 papillary thyroid carcinomas, 30 matched lymph nodes with metastatic papillary thyroid carcinoma and 5 non-cancer thyroid tissues. Galectin-1 and 3 protein expression was determined by immunohistochemistry in these samples. RESULTS: Significant expression differences in all tested galectin family members (1, 2, 3, 4, 7, 8, 9, 10 and 12) were noted for mRNA in papillary thyroid carcinomas, with and without lymph node metastasis. Galectin-1 protein was more strongly expressed than galectin-3 protein in papillary thyroid carcinoma. Galectin-1 protein was found to be overexpressed in 32% of primary papillary thyroid carcinomas. A majority of lymph nodes with metastatic papillary thyroid carcinoma (53%) had significantly increased expression of galectin-1 protein, as did 47% of primaries with metastases. Galectin-1 mRNA levels were decreased in the vast majority (94%) of primary thyroid carcinomas that did not have metastases present. Galectin-3 protein levels were noted to be overexpressed in 15% of primary papillary thyroid carcinomas. In primary papillary thyroid carcinoma with lymph node metastases, 32% had over expression of galectin-3 protein. Overexpression of galectin-3 mRNA was noted in 58% of papillary thyroid carcinomas and 64% of lymph nodes bearing metastatic papillary thyroid carcinoma. Also, primary papillary thyroid carcinoma with lymph node metastases had significantly higher expression of galectin-3 mRNA compared to those without lymph node metastases. CONCLUSION: Galectin family members show altered expression at the mRNA level in papillary thyroid cancers. Overexpression of galectin-1 and 3 proteins were noted in papillary thyroid carcinoma with lymph node metastases. The results presented here demonstrated that galectin-1 and galectin-3 expression have important roles in clinical progression of papillary thyroid carcinoma.

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Pallenberg is represented in No 9 representing himself

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Water soluble dinickel(II) complexes Ni-2(L)(2)(1-2)](NO3)(4) (1-2), where L1-2 are triazole based dinucleating ligands, were synthesized and characterized. The DNA binding, protein binding, DNA hydrolysis and anticancer properties were investigated. The interactions of complexes 1 and 2 with calf thymus DNA were studied by spectroscopic techniques, including absorption and fluorescence spectroscopy. The DNA binding constant values of the complexes 1 and 2 were found to be 2.36 x 10(5) and 4.87 x 10(5) M-1 and the binding affinities are in the following order: 2 > 1. Both the dinickel(II) complexes 1 and 2, promoted the hydrolytic cleavage of plasmid pBR322 DNA under both anaerobic and aerobic conditions. Kinetic data for DNA hydrolysis promoted by 1 and 2 under physiological conditions give the observed rate constants (k(obs)) of 5.05 +/- 0.2 and 5.65 +/- 0.1 h(-1), respectively, which shows 10(8)-fold rate acceleration over the uncatalyzed reaction of ds-DNA. Meanwhile, the interactions of the complex with BSA have also been studied by spectroscopy. Both the complexes 1 and 2 display strong binding propensity and the binding constant (K-b), number of binding sites (n) were obtained are 0.71 x 10(6) 1.47] and 5.62 x 10(6) 1.98] M-1, respectively. The complexes 1 and 2 also promoted the apoptosis against human carcinoma (HeLa, and BeWo) cancer cells. Cytotoxicity of the complexes was further confirmed by lactate dehydrogenase enzyme level in cancer cell lysate and content media. (c) 2013 Elsevier Ltd. All rights reserved.

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铬系催化剂是合成1,2-聚丁二烯和3,4-聚异戊二烯的一种主要催化剂体系,1,2-聚丁二烯和3,4-聚异戊二烯是制造高性能轮胎的重要原料。本论文研究了以含氮化合物和含磷化合物为配体的铬催化剂合成1,2-聚丁二烯和3,4-聚异戊二烯的反应规律。 1. 以邻菲咯啉为配体的铬催化剂在己烷中50℃下可获得1,2-结构、顺-1,4-结构和反-1,4-结构单元含量分别约为50%、30%和20%,分子量呈双峰分布的聚丁二烯。改变聚合温度,可有效控制聚合物的1,2-结构含量和分子量及分布。催化剂通过预陈化方式,可有效抑制低聚物的生成。 2. 以亚磷酸二烷基酯为配体的铬催化剂是合成1,2-聚丁二烯的高效催化剂,所得聚合物具有高的1,2-结构含量(> 78%)。改变烷基铝和亚磷酸二烷基酯的结构,可以得到高熔点或低熔点间同1,2-聚丁二烯和无规1,2-聚丁二烯。催化剂以现配方式的活性最高。 3. 以磷酸三苯酯为配体的铬催化剂可获得间同1,2-聚丁二烯,而聚合物中含有低聚物。催化剂以现配方式的活性最高。聚合物的熔点,低聚物的含量与磷酸三苯酯的结构有一定的关系。 4. 以邻菲咯啉为配体的铬催化剂在50℃下聚合异戊二烯,具有高的催化活性,可获得3,4-结构含量约67%的高分子量无规3,4-聚异戊二烯。催化剂的组成对聚合物的微观结构无明显影响。改变聚合温度,可有效控制聚合物的3,4-结构含量和分子量及分布。

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1,2-聚丁二烯和3,4-聚异戊二烯是制造高性能轮胎的原料。本论文研究了以含磷化合物为第三组份的铁催化剂合成1,2-聚丁二烯和3,4-聚异戊二烯的反应规律:1.以二乙基亚磷酸酷为第三组份的铁催化剂可在己烷中,较高温度(50℃)下聚合1,3-丁二烯。通过控制催化剂组份的配比,可制备间同和无规1,2-聚丁二烯。所得间同1,2-聚丁二烯的1,2-结构含量为91%,间规度为90%;所得无规1,2-聚丁二烯的硫化胶具有优异的抗干、湿滑性能。2.以三苯基磷酸酷为第三组份的铁催化剂是合成高间同1,2一聚丁二烯的高效催化剂。所得聚合物具有高的1,2-结构含量(ca.95%),高的间规度(ca.95%)。聚合物的微观结构与催化剂组成等反应因素无关。3.以二烷基亚磷酸醋为第三组份的铁催化剂可在己烷中,较高温度(50℃)下聚合异戊二烯。二烷基亚磷酸醋中烷基影响聚合活性的顺序为乙基一甲基>正丁基>异辛基。所得聚异戊二烯的3,4(含1,2)结构含量保持在60%左右,不受反应条件的影响。4.改性甲基铝氧烷(MMAO)活化的铁催化剂聚合异戊二烯,在相当低的MMAO用量下(Al/Fe=20,摩尔比)即有高的催化活性。溶剂影响聚合活性的顺序为甲苯>环己烷>己烷>二氯甲烷。所得聚异戊二烯的3,4(含1,2)结构含量稳定在60%。

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本论文从2,3'-联吡啶出发,利用两个吡啶环上氮的反应活性差异,选择性合成了单烷基盐1-甲基-2,3,-联吡啶盐、1-甲基-1,一氧-2,3,-联吡啶盐和1'-甲基/节基2,3气联吡啶盐,还原单烷基盐合成了天然生物碱毒黎碱、安那他品和异毒黎碱及其衍生物:对异毒黎碱的合成由还原N,-节基盐后脱节基简化为一步实现还原和脱节基直接得到异毒黎碱。通过用(R)-BINOL和(S)-BINOL对N,-节基异毒黎碱拆分得到了旋光纯的N,-节基异毒黎碱和异毒黎碱,-N,-节基异毒黎碱的旋光度[a]D20:-61.50(c=2.0,乙醇),卜异毒黎碱的旋光度fa]D20:-14.4"(c-1.0,乙醇);将C关异毒黎碱用(RMTPA和(s)MT队衍生为Mosher酞胺,应用Mosllel方法确定了C)异毒黎碱手性中心的绝对构型为R型,即(R)-C)异毒黎碱,同时发现,由(R)一MTPA合成的Mosller酞胺中顺式旋转异构体占优。而通常在环胺的Mosller酞胺中,是反式旋转异构体占优。这一例外被MollteCarlo模型模拟计算结果解释:稀溶液中C卜异毒黎碱的Moshel-酞胺,顺式构型能量上比反式更有利。不对称合成天然生物碱更具有挑战性。对异毒黎碱还原合成中的呱l淀烯类中间体,用BINAP-灿催化体系进行了催化不对称还原的合成研究,氢化N'-节基-1,,4,,5,,6,-四氢一2,3,一联吡陡时得到了最高为21.5%的对映体选择性,而对N'-节基一1,,2',5',6,-四氢-2,3'一联吡陡的氢化则只得到了不超过10.0%的对映体选择性。

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胺类萃取剂具有其独特优点,特别是伯胺,因含有活泼氢,既能作为“阴离子交换剂”,又能与被萃的含氧金属络阴离了形成氢键而溶剂化,同时伯胺为一路易斯碱,可作为配体与某些金属离子形成配位键等,因而已广泛地用于金属离子的提纯与分离工业中。然而,1)为了寻找新的、更有效的萃取及协同萃取体系,以适应分析分离各种金属离子,改善金属离子的分离工艺;2)研究萃取和协同萃取的一般规律,探寻其内在规律性,充实完善萃取化学原理的内容;3)研究多元配合物的组成、结构和机理;4)系统地研究和比较不同结构胺类萃取剂与其它萃取剂对金属离子的萃取及协同萃取的相互作用,探讨多元配合物的形成条件等,因此,研究伯胺N_(1923)与其它萃取剂在不同酸度、不同条件,不同体系中对Zn(II)、Cd(II)、Re(III)的萃取及协同萃取具有一定意义。本文分别研究了伯胺N_(1923)与中性磷试剂对ZnCl_2、CdCl_2、Zn(SCN)_2的协同萃取;伯胺N_(1923)与HPMBP对RE(III)的协同萃取以及伯胺N_(1923)在不同介质中对Sc(III)的萃取机理等,并用得到了一些有意义的结果与结论。一、伯胺N_(1923)与中性磷萃取剂(TBP, DBBP)对Zn(II)、Cd(II)的协同萃取1. 伯胺N_(1923)与TBP、DBBP对ZnCl_2的协萃取 研究了伯胺N_(1923)与TBP、DBBP的正庚烷溶液从盐酸介质中对ZnCl_2的萃取机理,用斜率法、等摩尔系列法确定了协萃配合物组成为:(RNH_3Cl)_3·ZnCl_2·B、(RNH_3Cl)_2·ZnCl_2·B (B = TBP·DBBP)协萃反应为:ZnCl_2 + (RNH_3Cl)_3_((o)) + TBP_((o)) →~(K_(12)(TBP) (RNH_3Cl)_3·ZnCl_3·ZnCl_2·TBP_((o)) ZnCl_2+Z/3(RNH_3Cl)_(3(o)) + DBBP_((o)) → (RNH_3Cl)_2 · ZnCl_2·DBBP_((o))协萃配合物生成反应为:(RNH_3Cl)_3·ZnCl_(2(o)) + TBP_((o))→~(B_(12)(TBP) (RNH_3Cl)_3·ZnCl_2·TBP_((o)) (RNH_3Cl)_3·ZnCl_(2(o)) + DBBP_((o)) →~(B_(12)(DBBP) (RNH_3Cl)_2·ZnCl_2·DBBP_((o)) + RNH_3Cl_((o))同时发现,中性磷试剂对Zn(II)的协萃效应大小影响有下列关系:DBBP>TBP。并求得了协萃反应平衡常数和协萃配合物生成反应平衡常数。在研究溶剂对协同效应影响时发现,对芳香烃及其衍生物,分配比(D)与溶剂介电常数(ε)的关系为D_∝1/ε,而对芳香烃及其衍生物,分配比(D)与介电常数(ε)的关系为D_∝ε。讨论了温度对协萃反应的影响,对协萃配合物的IR、NMR谱也进行了研究。2.伯胺N_(1923)与TBP对Zn_(SCN)_2的协同萃取研究了伯胺N_(1923)与TBP的庚烷溶液从硝酸底液中对Zn(SCN)_2的萃取机理,用等摩尔系列法、斜率法确定了TBP和Zn(SCN)_2以及伯胺N_(1923)与TBP对Zn(SCN)_2的协萃配合物组成分别为:Zn(SCN)_2·3TBP. (RNH_3)_2Zn(SCN)_4·TBP,协谇反应为:Zn(SCN)_4~(2-) + (RNH_3NO_3)_(2(o)) + TBP_((o)) → (RNH_3)_2Zn(SCN)_4·TBP_((o)) + 2NO_3~-协萃配合物三种可能生成反应为(RNH_3)_2Zn(SCN)_(4(o)) + TBP_((o)) → ~(B'12) (RNH_3)_2Zn(SCN)_4·TBP_((o)) (a) (RNH_3NO_3)_(2(o)) + Zn(SCN)_2·3TBP_((o)) + 2SCN~-→~(β"12)→(RNH_3)Zn(SCN)_4βTBP_((o))+2TBP_((o))+2NO_3~- (b) (RNH_3NO_3)_(2(o)) + (RNH_3)_2Zn(SCN)_(4(o)) + 2SCN~- + Zn(SCN)_2.3TBP_((o)) →~(β"12)→R(RNH_3)_2Zn(SCN)_4.TBP_((o)) + 2NO_3~- + TBP_((o)) (c) 求得了协萃反应及生成反应的平衡常数,并由生成反应常数可知:β"'_(12) > β'_(12) > β"_(12),即反应(c)对协萃配合物的生成贡献最大,其次反应(a),最小的是反应(b),同时还发现,不同阴离子对协萃效应影响有下列关系:SCN~- > Cl~_。并对协萃配合物的IR谱进行了研究,讨论了温度对协萃反应的影响。3. 伯胺N_(1923)与TBP、DBBP对Cd(II)的协同萃取研究了伯胺N_(1923)与TBP、DBBP的正庚烷溶液从盐酸介质中对Cd(II)的协同萃取,用等摩尔系列法、斜率法确定了协萃配合物组成为(RNH_3Cl)_2·CdCl_2·B,协萃反应及协萃配合物生成的反应分别为:CdCl_2 + 2/3 (RNH_3Cl)_(3(o)) + B_((o)) →~(K_(12)) → (RNH_3Cl)_2·CdCl_2·B_((o)) (RNH_3Cl_3)·CdCl_2_((o)) + B_((o)) →~(BR)(RNH_3Cl)_2·CdCl_2·B_((o)) + RNH_3Cl_((o))求得了协萃反应及生成反应平衡常数,计算了协萃反应的热力学函数值,结果还发现与Zn(II)协同萃取比较,协同效应大小有下列关系:Zn(II) > Cd(II),由实验结果证实了“萃取效应大,则协萃效应小,反之,萃取效应小,则协同效应大”这一结论。并对协萃配合物的IR、NMR谱进行了研究。二. 伯胺N_(1923)与HPMBP对RE(III)的协同萃取研究了伯胺N_(1923)与HPMBP的二甲苯溶液在盐酸介质中对RE(III)的协萃机理(RE~(3+ = La~(3+), Pr~(3+), Eu~(3+), Gd~(3+), Tb~(3+), Er~(3+), Yb~(3+)和Y~(3+))用斜率法及等摩尔系列法确定了协萃配合物组成为RNH_3Ln(PMBP)_4。求得了关于Pr(III)的协萃反应及生成反应的平衡常数值,协萃反应及生成反应分别为:Ln~(3+) + 4HPMBP_((o)) + RNH_3Cl_((o)) → RNH_3LN(PMBP)_(4(o)) + 4H~+ + Cl~- Ln(PMBP)_(3(o)) + RNH_3Cl_((o)) → RNH_3Ln(PMBP)_(4(o)) + H~+ + Cl~- 结果还发现协萃系数(R)随稀土元素的原子序数(Z)递变而出现“双峰效应”(未见文献报道),而且随RNH_3Cl浓度增加到某一一出现反协同效应。同时研究了关于Pr(III)协萃配合物的IR、NMR谱。三、伯胺N_(1923)在硝酸盐及硫氰酸盐混合介质中对Sc(III)的萃取研究了RNH_3NO_3在硝酸盐和硫氰酸盐混合介质中萃取Sc(III)的机理,结果发现,钪是以Sc(OH)_2~+形式萃入有机相的,且SCN~-, NO_3~-对RNH_3nO_3萃取Sc(III)具有协同效应,并且斜率法、连续变化法及PH值测定确定了萃取反应为:Sc(OH)_2~+ + SCN~- + 2(RNH_3NO_3)_(2((o)) → (RNH_3nO_3)_4.Sc(OH)_2SCN_((o)) Sc(OH)_2~+ + SCN~- + NO_3~- + (RNH_3NO_3)_(2(o)) → (RNH_3NO_3)_2.Sc(OH)(SCN)NO_3 + OH~-求得了反应的平衡常数及热力学函数值。