56 resultados para Mutianus Rufus, Conradus, 1471-1526.


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Three kinds of hydroxy-terminated oligomers were synthesized and characterized by IR, DSC and GPC. The oligomers were crosslinked by melaminealdehyde resin. The orientation and relaxation of the poled and crosslinked polymers were studied by UV-Vis spectra. It was shown that polymers had high orientational stability after corona-poling and crosslinking.

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The structural characterization of folded and unfolded haemoglobin has been performed by scanning tunnelling microscopy (STM) for the first time. STM images show an oval-shaped pattern for the folded structure of this protein, and moreover two dimers consisting of one haemoglobin molecule can be clearly discerned. The dimensions of a folded molecule were determined as 6.4 x 5.4 x 0.7 nm(3), which are in good agreement with the known size obtained from X-ray analysis. We have found that unfolding of haemoglobin molecules on the surface of highly oriented pyrolytic graphite (HOPG) can be achieved by electrochemical deposition. The STM analysis indicates clearly that the tertiary structure of the protein was lost by electrochemical deposition, and most of the haemoglobin molecules were almost fully extended and exhibited a twisted rope-like or a rod-like aggregated structure. Our investigation demonstrates the capability of the electrochemical method in denaturing this redox protein and in preparing stable biological samples for use in STM imaging.

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用双羟基偶氮(或氧化偶氮)苯化合物与对苯二甲酰氯缩聚反应合成了端羟基偶氮(或氧化偶氮)苯低聚物。将其与丁醇醚化氨基树脂进行电场极化交联反应合成交联型非线性光学聚合物。利用红外光谱和紫外可见吸收光谱分别对交联反应、电场极化取向稳定性进行了研究。

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计算了43种不对称变色酸双偶氮膦酸型显色剂的A_m拓扑指数,并将其与结构选择性因子相结合,用于偶氮类显色剂结构与铈显色反应对比度的相关性研究,讨论了显色剂结构对拓扑指数及对比度的影响。

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由六次甲基四碲富瓦烯(HMTTeF)所形成的有机化合物晶体,有两种可能的化学结合形式:一种是分子中的Te原子离子化,形成离子型化合物;另一种是分子中心共轭π键离子化,或者形成离子型化合物,或者形成混合价态型化合物。至今被报道的HMTTe F化合物晶体都只含有其中一种化学结合形式,而标题化合物晶体则同时含有上述两种化学结合形式。本文将该晶体的晶体结构、化学结合与电导性的关系作简要的讨论。

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海洋是一个巨大的天然产物宝库,约占地球表面积70%的海洋蕴藏着80%的生物资源。由于海洋生态环境的特殊性,导致海洋生物能够产生大量结构独特多变和活性特殊多样的代谢产物。我国海域辽阔,海洋资源丰富,为寻找结构新颖、生理活性独特的先导化合物,加强对海洋资源的开发利用,本论文对中国沿海的三种海洋红藻和两株放线菌次生代谢产物以及生物活性进行研究,为新药研究与开发提供模式结构和药物前体。 对红藻似瘤凹顶藻Laurencia similis乙酸乙酯萃取物进行分离纯化,从中得到单体化合物35个,通过波谱学方法(IR、MS、NMR等)鉴定了他们的结构。分别为:2, 2, 5, 5, 6, 6-sixibromo-3, 3-bi-1H-indole (1),3,5-dibromo- 1-methyl-indole (2),3',5',6,6'-tetrabromo-2,4-dimmethyldiphenyl ether (3),1,2,5- tribromo-3-bromoamino-7-bromomethylnaphthalene (4),2,5,8-tribromo-3-bromo- amino-7-bromomethylnaphthalene (5),2,5,6-tribromo-3-bromoamino-7-bromo- methylnaphthalene (6), 2,5,6,5',6'-pentabromo-3,4,3',4'-tetramethoxybenzophenone (7), (4E)-1-bromo-5-[(1'S*,3'R*)-3'-bromo-2',2'-dimethyl-6'-methylenecyclohexyl] -3-methylpent-4-ene-2,3-diol (8),4-hydroxy-Palisadin C (9),Isopalisol (10),Luzonensol (11),Palisadin B (12),Aplysistatin (13),Palisadin A (14),5-Acetoxypalisadin B (15),Aristolan-1(10)- en-9-ol (16),Aristol-8-en-1-one (17),Aristolan-9-en-1-one (18),Aristolan-1(10)-en- 9-one (19),Aristofone (20),Aristolan-1(10)-8-diene (21),Aristolan-1,9-diene (22),10-Hydroxyaristolan-9-one (23),7,11,15-trimethyl-3-methylene-hexadecan-1,2-diol (24),3β-Hydroxyergosta- 5,24(28)-dien-7-one (25),Isofucosterol (26),β-sitosterol (27),豆甾-4-烯-3α,6β-二醇 (28),Cholesta-5-en-3β-ol (29),Stigmasterol (30),2,3,5,6-四溴-吲哚 (31),2,3,6-tribromo-1H-indole (32),3,5,6-tribromo-1-methylindole (33),3,5,6-tribromo -1H-indole (34),2,3,5-tribromo-1-methylindole (35),其中化合物1-9为新化合物,化合物10-15、20和化合物24-30均为首次从该种海藻中得到。对新化合物1-9进行PTP1B酶抑制剂活性筛选,新化合物1、3、7显示强的PTP1B酶抑制活性。 对红藻齐藤凹顶藻Laurencia saitoi乙酸乙酯萃取物进行分离纯化,从中得到单体化合物11个,通过波谱学方法(IR、MS、NMR等)鉴定了他们的结构,分别为:2-hydroxyl-Luzofuranone (1),2-hydroxyl-Luzofuranone B (2),4-hydroxyl-Palisudin C (3),2-bromo-γ-ionone (4),Aplysistatin (5),5-Acetoxypalisadin B (6),Palisadin B (7),Palisadin A (8),Pacifigorgiol (9),豆甾-4-烯-3α,6β-二醇 (10),2, 3, 5, 6-四溴-吲哚 (11),其中化合物1-4为新化合物,所有化合物均为首次从该种海藻中得到。通过MTT法对分离得到的新化合物1-4进行肿瘤细胞毒活性筛选,结果显示4个新化合物对所测肿瘤细胞株均无明显的活性。 对红藻瘤状软骨凹顶藻Chondrophycus papillous乙酸乙酯萃取物进行分离纯化,从中得到单体化合物5个,通过波谱学方法(MS、NMR等)鉴定了他们的结构,分别为邻苯二甲酸二丁酯 (1),邻苯二甲酸二异辛酯 (2),胆甾醇 (3),3,7,11,15-tetramethyl-hexadec-2-en-1-ol (4),4-羟基苯甲醛 (5),所有化合物均为首次从该种海藻中得到。 对海洋放线菌M159乙酸乙酯萃取物进行分离纯化,从中得到单体化合物13个,通过波谱学方法(MS、NMR等)鉴定了他们的结构,分别为:5-(4',6'-dihydroxy-6-methyloctyl)furan-2(5H)-one (A),phenethyl alcohol (1),4-羟基苯甲醛(2),anthranilic acid (3),4-Hydroxy-3-methoxy- phenyl-propionic acid (4),5-(6,7-dihydroxy-6-methyloctyl)furan-2(5H)-one (5),p-Hydroxyphenylethyl alcohol (6),3-Indoleacrylic acid (7),Indol-3-carboxylic acid (8),Adenine cordyceposide (9),腺嘌呤核苷(10),尿嘧啶核苷(11),Thymidine (12),其中化合物A为新化合物。所有化合物均为首次从该株放线菌中得到。 对海洋放线菌L211乙酸乙酯萃取物进行分离纯化,从中得到单体化合物15个,通过波谱学方法(MS、NMR等)鉴定了7个结构,分别为:spatozoate (1),anthranilic acid (2),3-Indolylethanol (3),1-Acetyl-β-carbolin (4),p-Hydroxyphen- ylethyl alcohol (5),Indole-3-acetic acid (6),Indol-3-carboxylic acid (7),所有化合物均为首次从该株放线菌中得到。

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本发明涉及一种改善睡眠的保健药物组合物,由丁香、肉豆蔻、肉桂、阿魏、山奈、黑胡椒按公知制剂方法制成药剂学上所述的任何一种剂型;本发明具有安神养心、改善睡眠作用。

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20世纪90年代以后,由于科学技术的迅猛发展,知识─技术─产品的周期日益缩短,如何加速开发质优价廉的新产品就成为企业竞争的核心内容。21世纪即将到来,世界无疑将沿着20世纪的道路继续向前发展,它的趋势是:新产品开发速度日益加快、产品生命周期不断缩短、生产批量越来越小、市场竞争日趋激烈;加上环太平洋地区的兴起,有能力参与这场竞争的企业不断增多。这一切虽给企业带来了机遇,但也给企业造成了严酷的生存环境。为了适应这种环境,1991年美国在总结日本、德国和本国经验的基础上,提出把现有企业改造成敏捷制造企业(AgileManufacturingEnterprise)的模式,并认为这是奠定美国21世纪经济霸主地位的战略举措。敏捷制造企业是从客观经济发展的实践中总结出来的。我国如何改造企业并和世界经济接轨,敏捷制造企业给我们提出了值得高度重视的发展方向,本文对此作了较为详尽的论述。

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Focal beam analysis is a method for assessment of acquisition geometries that is directly linked to pre-stack migration. About dealing with the complex subsurface structures, the conventional survey design methods which do not take into account the subsurface are no longer valid. Based on the Fourier finite-difference (FFD) large-step wave field extrapolation and Born-Kirchhoff (BK) small-step wavefield interpolation, the thesis presents a rapid resolution analysis of 3D seismic survey design by focal beams in complicated media. Subsequently, The SEG/EAEG salt model is used to illustrate the method. Based on the focal beam resolution definition, each kind of influence factor is discussed. The focal beam analysis usually is carried out in a single frequency, but the actual seismic waves always contain a frequency bandwidth. In this thesis, theoretical relationship between focal beam analysis and frequency is derived. Since the effects of focal beam analysis are linear with frequency simply, the multi-frequency focal beam analysis using interpolation is developed. At the same time, the resolution of different frequency bandwidth is interconvertible in accordance with Signal uncertainty principle. The resolution of all frequency bands can be calculated by using only a few focal beam analysis for a seismic survey. In the last section of this thesis, I propose a new approach to predicting acquisition footprint, based on the assumption of Common-Middle-Point stack without constructing a special velocity model. The approach is a simplistic analytical method in which the acquisition footprint pattern is a weighted, linear summation of limited-offset fold-of-stack plots. Because the value of acquisition can be got by quantificational and rapidly calculating, we can exactly do a comparative analysis among different plans of seismic survey by this method.

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综述了土壤汞的来源,以及汞在土壤中的迁移方式、转化模式和富集行为;并介绍了当前几种土壤汞污染的防治对策,重点讨论了改进农耕技术、减少人为活动向大气的排汞量、生物修复以及电解法等方法,最后对土壤汞的研究方向进行了展望。