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991.
DOPC,DOPE和神经酰胺对鞘磷脂/胆固醇双层膜结构的影响 总被引:1,自引:1,他引:0
用LB技术和原子力显微镜(AFM)研究了1,2-二油酸甘油-3-磷脂酰胆碱(DOPC)、1,2-二油酸甘油-3-磷脂酰乙醇胺(DOPE)和神经酰胺(Ceramide)对鞘磷脂(SM)/胆固醇(Chol)结构的影响. 实验结果表明, 在表面压力较低时, 每种混合脂双层膜都呈现均匀分布的脂双层结构. 随着表面压力的增加, 形态发生了明显的变化: (1) SM/Chol二元组分双层膜形成均一的液态有序相微区结构, 衬底覆盖率达到80%; (2) DOPC的加入促使SM/Chol双层膜出现相分离现象, SM/Chol形成的液态有序相 “岛状” 微区结构漂浮在液态无序相的DOPC上部, 约占总面积的30%; (3) DOPE与SM/Chol形成的双层膜明显不同于DOPC/SM/Chol, 呈现出液态无序相、液态有序相及凝胶相3相共存的结构; (4) Ceramide诱导了SM/Chol双层膜结构发生重排, 两层脂分子间发生翻转形成囊泡结构, 部分神经酰胺从液态有序相中分离形成小颗粒结构. 在较高膜压下, 各系统都呈现出具有特定形态的双层膜结构. 分子官能团的成键能力决定了双层膜形态结构. 相似文献
992.
Four-mode continuous-variables entangled state: generation from beam splitter, a parametric down-conversion and a polarizer 下载免费PDF全文
We introduce a new kind of four-mode continuous variable entangled
state in Fock space. The completeness relation and the partly
nonorthonormal property of such a state are proven. The scheme to
generate this state is presented by combining a symmetrical
beamsplitter, a parametric down-conversion and a polarizer. After
making a single-mode quadrature amplitude measurement, the remaining
three modes are kept in entanglement. And its applications are also
discussed. 相似文献
993.
New two-mode intermediate momentum-coordinate representation with quantum entanglement and its application 下载免费PDF全文
We construct four linear composite operators for a two-particle
system and give common eigenvectors of those operators. The
technique of integration within an ordered product (IWOP) of
operators is employed to prove that those common eigenvectors are
complete and orthonormal. Therefore, a new two-mode intermediate
momentum-coordinate representation which involves quantum
entanglement for a two-particle system is proposed and applied to
some two-body dynamic problems. Moreover, the pure-state density
matrix | ξ 1 ,ξ 2 >C,DC,D< ξ 1 ,ξ 2 | is a Radon
transform of Wigner operator. 相似文献
994.
Novel Wronskian Solutions to Boussinesq Equation 总被引:1,自引:0,他引:1
YAO Yu-Qin LIU Yu-Qing JI Jie CHEN Deng-Yuan 《理论物理通讯》2007,48(4):577-583
The new method for constructing the Wronskian entries is applied to the Boussinesq equation. The novel Wronskian solutions to it are obtained, including solitons, rational solutions, Matveev solutions, and complexitons. 相似文献
995.
References: 《理论物理通讯》2007,47(1):31-34
We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of the integration within an order product (IWOP) technique. We also calculate the transition from classical transformation of variables in the states to quantum unitary operator, deduce a new multi-mode squeezing operator, and discuss its squeezing effect. In progress, it indicates that the IWOP technique provides a convenient way to construct new representation in quantum mechanics. 相似文献
996.
Stphane Bredeau Laura Boggioni Fabio Bertini Incoronata Tritto Fabien Monteverde Michaël Alexandre Philippe Dubois 《Macromolecular rapid communications》2007,28(7):822-827
Homogeneous surface coating of multi‐walled carbon nanotubes is achieved for the first time by in situ copolymerization of ethylene (E) and 2‐norbornene (N) as catalyzed directly from the nanotube surface previously treated by a highly active metallocene‐based complex, i.e., rac‐Et(Ind)2ZrCl2/MMAO‐3A. The copolymerization reaction allows for the destructuration of the native nanotube bundles, which upon further melt blending with an ethylene–vinyl acetate copolymer (27 wt.‐% vinyl acetate) matrix, leads to high‐performance polyolefinic nanocomposites. The microstructural analysis of the surface‐coating copolymer was carried out by 13C NMR spectroscopy and allowed determination of the actual N content incorporated along the chains. Depending on the experimental conditions used (e.g., E pressure, solvent, feed N concentration) the relative quantity of E–N copolymer can be tuned, as well as the N content in the formed copolymers and accordingly their glass transition temperature.
997.
Based on dynamical theories of water waves and dynamics of Mindlin thick plates,the investigation of the wave-induced responses and the vibration reduction of an elastic floating plate are presented using the Wiener-Hopf technique.Without regard to the case of elastic connector,the calculated results obtained by the present method are in good agreement with those from the literature and the experiment.It can be shown that the present method is valid.Relations between the spring stiffness to be used to connect the sea bottom and the floating plate and the parameters of wave-induced responses of floating plates are investigated using the present method.Therefore, these results can be used as theoretical bases for the design stage of super floating platform systems. 相似文献
998.
999.
1000.
杯芳烃衍生物和丙烯酰胺作为复合功能单体的分子印迹聚合物对海因类化合物的选择性识别研究 总被引:2,自引:0,他引:2
以杯[4]芳烃衍生物+丙烯酰胺作为复合功能单体,将其运用到分子印迹技术中,对海因类化合物R-苄基海因进行选择性识别.研究结果表明,由单一的杯[4]芳烃衍生物或丙烯酰胺作为功能单体的分子印迹聚合物对R-苄基海因的选择性均不高,而由杯[4]芳烃衍生物+丙烯酰胺作为复合功能单体的分子印迹聚合物对模板分子具有较高的特异选择性. 相似文献