双分子的
- 与 双分子的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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In this thesis the planar bilayer lipid membranes inlaid with oxide cholesterol , phosphatidylcholine or cephalin have been prepared .The effects of membranes formulas on membranes stability and zinc ions transfer ability have also been studied.
中文摘要采用氧化胆固醇与磷脂混合作为成膜液制备双分子层脂质膜的方法,研究了制备平板双分子层脂质膜的配方和成膜条件,并对制得的双分子层脂质膜的稳定性、离子通透性、离子选择通过性能、双层膜中氧化胆固醇对通透性的影响等进行了研究。
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Since most of the large molecules containing phosphorus element have double bonds, it is necessary to consider the special structures of double bonds in order to deal with these large systems more accurately. So, based on density functional theory and electronegativity equalization principle, applying a general atom-bond electronegativity equalization method , using separated program, through regression and least-squares optimization , the parameters of atoms and bonds in molecules are determined . By these parameters , the charge distributions and the energy of some molecules containing phosphorus element, especial the fragment of DNA, RNA, are calculated . The results are quite good.
由于这些含磷生物大分子体系都含有双键,为了明确的处理双键,进而更准确的解释带有双键和共轭双键的含磷生物大分子结构与性质的关系,我们以密度泛函理论~([1-4])和电负性均衡原理~([5-9])为基础,应用和开发原子-键电负性均衡方法中的σπ模型,利用最小二乘法,拟合确定了一些分子(含碳、氮、氧、氢以及磷等原子)的各种类型原子及化学键区域的参数,并利用上述参数计算了一些多聚核苷酸的电荷分布以及分子的总能量,进行了讨论,得到的结果可以和从头算相媲美。
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Meanwhile, the isomer with a larger change of dipole moment has larger value of the first hyperpolarizability during the charge-transfer process.
5, 6, 7顶点双取代碳硼烷桥连分子受推拉电子基的影响,5, 6, 7顶点碳硼烷的构型发生一定变化,碳硼烷中两个C原子间的距离变长;同时碳硼烷中两个C原子取代位置的不同,影响了分子的稳定性和极化率,取代基团与碳硼烷中成键数较低的C原子相连的异构体,稳定性较好且具有大的极化率; 5,6,7顶点双取代碳硼烷桥连分子形成一维结构有利于分子内电荷转移,在电荷转移过程中偶极矩变化较大的体系,其二阶NLO系数也较大。
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These membranes are biologic barriers that selectively inhibit the passage of drug molecules and are composed primarily of a bimolecular lipid matrix, containing mostly cholesterol and phospholipids.
这些细胞膜起着生物屏障的作用,有选择地抑制某些药物分子的通过。细胞膜主要由双分子的脂质基质构成,主要成份是胆固醇和磷脂。
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The UV and IR spectroscopic studies of the monomer films showed that the photoreaction ratio of monomer (about 50%) was higher than the corresponding photosensitive polymer (about 10%, PVCi). The polarized IR spectra proved that obvious anisotropic absorption was displayed in the irradiated photosensitive film. With polarizing microscopy method, we found that these kinds of photoalignment films exhibited good alignment ability, and the stability of the photoalignment film could reach about 100℃. 2 A photosensitive self-assembled monolayer was fabricated that contained photo-cycloadditable groups, such as, coumarin and cinnamate. The reaction process were detected by contact angle method because the IR absorption of monolayer was very weak. The photosensitive self-assembled monolayer promote uniform alignment of nematic liquid crystals by LPUV, and it thermal stability could reach about 130℃. 3 A cationic bolaform amphiphiles was synthesized that had two photosensitive double bonds, and can be polymerized by ultraviolet. A layer-by-layer self-assembled deposition film was prepared in aqueous solution by using this material and poly (sodium 4-styrenesulfonate). The UV-Vis. spectra proved that the multilayers film was uniform and layer-by-layer. When LPUV irradiated the film, the photopolymerizable double bond underwent [2+2] cycloaddition, and the production of the reaction distributed along the polarized direction of incident LPUV. Polarized UV-Vis. spectra indicated that the irradiated self-assembled multiplayer film was anisotropic, and the dichromic ration is about 0.09, it is higher than the spin-coating method of photosensitive polymer or monomer. We used this anisotropic film as alignment layer of nematic liquid crystals, and obtained a uniform and stability alignment result, the static contrast ratio is about 100, which is very close to application of liquid crystal device. This thesis is an instance that the photochemical material was used in the physics region of liquid crystals, the route that was from photosensitive monomer, self-assembled monolayer film to self-assembled multiplayer film was undergone, by this logical research method photoailgnment of liquid crystal was extended and consummated.
围绕上述思路开展了如下工作:1合成了三种可进行光二聚反应的光敏小分子单体,LPUV 辐照制作了光控取向膜;用紫外-可见光谱法和红外光谱法分析了薄膜中的光化学反应,发现小分子的光反应程度可达到50%以上,至少比光敏高分子高出5倍;薄膜的偏振红外光谱证实,经过LPUV 辐照后薄膜出现了明显的各向异性;将小分子光控取向膜制成液晶器件,在偏光显微镜下观察看到均匀一致的液晶取向;并且热稳定性达到100℃左右,接近实用化要求。2制备了含肉桂酸、香豆素基团的自组装单层膜;采用接触角的方法监测自组装反应的动力学过程;紫外-可见光谱证实了自组装单层膜在石英基板表面形成;自组装单层膜经LPUV 辐照后能诱导液晶均匀取向,而且热稳定性可达130℃,热稳定性进一步提高。3合成了含有光敏双键的双季铵盐,在水溶液状态下将它和聚乙烯基苯磺酸钠沉积生成layer-by-layer 自组装多层膜,紫外-可见光谱证实这是一个逐层均匀的沉积;在LPUV 照射下,自组装膜中的光敏双键按照偏振方向发生[2+2]环加成反应,形成取向膜,用二向色性值评价的分子取向度高于高分子及小分子光控取向膜的水平;实验证明用自组装多层膜制成的液晶器件亮暗态均匀,静态对比度约为100,达到实用化器件的水平。
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Specifically, itcontains 8 chapters.In chapter 1, the formation, structures, properties and the futureprospect of liposome were thoroughly reviewed;In chapter 2, the stibility and permeability of phopholipid -eleostericacid liposome were studied together with the effect of polymerizationof eleostearic acid. This membrane system was very sensitive to 〓,the effect of 〓 was clarified to increase the aggregation/fusion ofliposomes and made the permeability of mixed liposomes much higher;In chapter 3, two polymerizable conjugated diyne bolaamphiphiles were synthesized. They could form very stable mixed liposome, andthe diyne could be polymerized by UV light in bilayer liposomes, as aresult, the stability of mixed liposome against solvent or surfactantafter polymerization were enhanced. In chapter 4, two kinds of amphiphilic amino acids were synthesized andstable liposomes were formed therefrom After the condensationpolymerization of amino acid in bilayer liposomes, stable polypeptide liposomes were obtained, which had lower phase transition temperatureand higher permeability.In chapter 5, four kinds of glycolipids were synthesized and theiraggregation behavior in water was comparied. When incorporated intophospholipid bilayer membranes, they could increase the phase transitiontemperatures and inhibit the aggregation and fusion of mixedliposomesat lower temperature.In chapter 6 and 7, three kinds of steroidal bolaamphiphiles withdifferent chain lengths were synthesized. Incorporation of steroidalmoiety to the center of lipid bilayer membrane obviously increased themobility of lipid membrane and shifted Tc to lower temperature side incomparasion with cholesterol. The bolaamphiphile which was shorter thanthe hosted lipid bilayer membrane thickness influenced the lipid packingmore obviously.
全文共分8章:第一章对脂质体的形成、结构、性质及展望进行了较为详细的文献综述;第二章研究了磷脂-桐酸脂质体的稳定性,通透能力及桐酸的聚合对这些性质的影响;磷脂-桐酸混合脂质体为一类对〓灵敏的脂质体,〓的作用首先是使脂质体集聚然后使脂质体融合,并加速内包荧光物的释放;第三章通过合成两种可聚合共轭双炔双极性双亲分子DDCA,DDOL,研究了共双炔分子在双分子层脂质体膜上的聚合及对脂质体性质的影响,聚合可以提高脂质体相对于溶剂及表面活性剂的稳定性;第四章合成了两类氨基酸为极性基团的双亲分子,它们均可以在超声下形成稳定的脂质体结构;氨基酸基团可以在脂质体上进行缩聚反应,若聚合后脂质体表面仍有足够的亲水能力,则可得到稳定的多肽型脂质体;聚合后脂质体的相变温度降低,通透能力增加;第五章合成了四种亲水基团为单糖基的双亲分子GL-l,GL-2,GL-3, GL-4,研究了它们在水中的分散情况、集合体形态与分子结构的关系;在DMPC双分子层膜中加入糖脂分子可以使脂质体的相变温度提高,阻止脂质体在低温放置时的集聚与融合;第六章-第七章合成了三种不同碳链长度的双极性含胆甾环双亲分子 CL-1,CL-2,CL-3;它们可以象胆固醇一样与磷脂混合形成稳定脂质体,胆甾环基团位于脂质体双分子层膜的中间;与胆固醇的作用相反,它们可以增加磷脂双分子层膜的流动性,降低混合脂质体的相变温度;三种分子的作用与其碳链长度和磷脂双分子层膜的厚度有关,比膜厚度短的分子影响最大。
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The two-photon absorption cross-sections of these styryl derivatives were determined by Z-scan technique, and the benzothiazolium derivatives exhibited the largest TPA cross-sections (10〓s·cm〓/photon) and the best power limiting ability at high operable incident intensity. The results show that the benzothiazolium derivatives are promising organic compounds as two-photon absorption optical limiting materials. 2. Several organic dyes active to 800nm femtosecond laser with D-π-A structure were designed and synthesized.
研究了它们的上转换荧光、上转换激射和光限幅行为,通过改变染料分子共轭体系的大小,首次实现了在576nm-635nm范围内的双光子上转换激光波长的调节,其中噻唑啉碘盐类二苯乙烯化合物的双光子上转换激射峰(576nm)是迄今在1064nm皮秒激光作用下能够得到的最短波长的激光;阴离子显著改变上转换激射效率,但对上转换荧光峰和激射峰的位置影响很小;增加溶液的浓度,上转换荧光光谱和激射光谱红移,并在一定的浓度范围内,能够有效的提高上转换激射效率;利用Z-扫描技术测定了染料分子的双光子吸收截面,发现苯并噻唑类染料分子的双光子吸收截面高达10〓s·cm〓/photon,而且在较大的入射光强范围内,这类染料分子具有较大的光限幅能力,是一类作为双光子吸收光限幅材料很有潜力的染料分子。
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Consequently we found two principal results in this investigation.(1) The crystal structures of molecular crystals formed from different chlorobenzoic acids and three kinds of organic bases showed that in addition to common hydrogen bondings, the weaker intermolecular interactions such as the C-H…O hydrogen bonding, the π-π stacking and electrostatic interaction play an important role in determining the packing modes of each molecular crystal.
在对双分子晶体结构的研究过程中,我们发现存在以下两条规律:(1)不同的氯苯甲酸与三种有机碱形成的双分子晶体的结构显示,除了常见的氢键作用外,弱的分子间相互作用,例如C-H…O类型的氢键、π—π相互作用、静电相互作用等对于不同分子堆积模式的形成也起到了很重要的作用。
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Even it seemed that such molecular compounds between an acid and a base were considered to easily crystallize by the formation of intermolecular hydrogen bondings or by the salt formation, the isolation of molecular crystals were not always successful.
虽然表面上看来,酸与碱很容易由于分子间的氢键作用或很容易由于盐的形成而得到双分子晶体,但是在实验过程中并不一定能够得到双分子晶体。
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To obtain the hyperfine structure and A-doubling parameters from the high-resolution spectra of novel free radicals directly, a set of algebraic formulae were developed to analyze the spectra with hyperfine structure and A-doubling resolution, some related important constants of NO have been obtained by analyzing its LMR spectra.
为了对新自由基分子激光磁共振光谱的早期标识提供一些必要的分子参数,我们发展了一组用于分析自由基分子高分辨光谱中的超精细和Λ-双分裂结构的代数方程,通过对NO超高分辨激光磁共振光谱中的超精细和Λ-双分裂结构的分析,获得了该分子的部分超精细结构参数,由此验证了该方法的可靠性,为新自由基分子的光谱标识提供了必要的参数和先导方法。
- 推荐网络例句
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The labia have now been sutured together almost completely.The drains and the Foley catheter come out at the top.
此刻阴唇已经几乎完全的缝在一起了,排除多余淤血体液的管子和Foley导管从顶端冒出来。
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To get the business done, I suggest we split the difference in price.
为了做成这笔生意,我建议我们在价格上大家各让一半。
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After an hour and no pup, look for continued contractions and arching of the back with no pup as a sign of trouble.
一个小时后,并没有任何的PUP ,寻找继续收缩和拱的背面没有任何的PUP作为一个注册的麻烦。