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51.
Ladder polysiloxanes (LPS) including both oxygen-bridged ladder polysilsesquioxanes (LPSQ) and organo-bridged ladder polysiloxanes (OLPS) are very important materials because of their excellent properties1. Adrianov et al. in 1960 attempted to prepare 1, …  相似文献   
52.
In this paper,a compound-type inclusion interval of basic coneigenvalues of(com- plex)matrix is obtained.The corresponding boundary theorem and isolating theorem are given.  相似文献   
53.
CONSTRUCTIONOFSOLUTIONSTOM-DRIEMANNPROBLEMSFORA2×2QUASILINEARHYPERBOLICSYSTEMCHENSHUXINGManuscriptreceivedDecember26,1994....  相似文献   
54.
The eudesmane derivative, (-)-10-epi-α-cyperone 1, is widely used as a chiral starting material for the synthesis of other fused-ring sesquiterpenes1. The first synthetic work was reported by Howe and co-workers via condensation of (+)-dihydrocarvone 2 with 1-diethylaminopentan-3-one methiodide in 32% yield2. Previously, our group reported the synthesis of compound 1 by treating ketone 2 with ethyl vinyl ketone (EVK) directly under different conditions1a, but the yields were not satisfacto…  相似文献   
55.
Benzimidazole compounds have attracted a renewed interest recently owing to theirpotential applications in high-performance composite materials, electronic chemicals,photosensitive materials, and their special potentials in biological and/or medicinalapplication1,2. Typically, aromatic compounds with near planar structures and contain-ing hydrogen-donor groups or groups, which are capable of being protonated, havespecial interactions with DNA via intercalation, hydrogen-bonding, and so on3.Me…  相似文献   
56.
1.IntroductionBioaerosolsaremicroorganismsorparticles,gases,vapors,orfragmentsofbiologicalorigin(i.e.,aliveorreleasedfromalivingorganism)thatexistintheair.Bioaerosolsareeverywhereintheenvironment.Underfavorableconditions,bioaerosolsareabletogrowandpropagateonavarietyofbuildingmaterialsandindoorsurfaces,causingindoorairpollution.Therefore,owingtotheirubiquitouspresenceinnature,bioaerosolsasapollutionsourcearealmostinevitableinarangeofenclosedenvironmentsandincommunityair(Kodama&McGee,1986;Lig…  相似文献   
57.
1. Introduction1.1 Silica nanoparticles and synthesis methods Silica (SiO2) nanoparticles are widely used in industry asan active filler for polymer reinforcement, a rheologicaladditive in fluids, a free flow agent in powders, and anagent for chemical mechanical polishing during IC (inte-grated circuit) fabrication (Sniegowski & de Boer, 2000).Silica powder is also used for producing silicon carbide(Koc & Cattamanchi, 1998) or opaque silica aerosols (Leeet al., 1995). Many methods can …  相似文献   
58.
邓真渝  章林溪 《物理学报》2015,64(16):168201-168201
采用非平衡态分子动力学方法研究了二维复杂囊泡在剪切流中的动力学行为. 模拟发现了复杂囊泡经典的翻滚(tumbling)、摇摆(trembling)和坦克履(tank-treading)行为, 还观察到由坦克履行为向平动行为(translating)的转变. 囊泡的平动行为与剪切率大小、复杂囊泡的形状密切相关. 当大囊泡均匀嫁接较多数目的小囊泡后, 其平动方式消失. 该研究有益于加深对囊泡在剪切流场中复杂性行为的理解.  相似文献   
59.
章林溪 《高分子科学》2011,29(6):684-691
The topic of self-assembly of cylinder-forming diblock copolymers(DBCPs) under spherical shell confinement in different surface fields is explored using real-space self-consistent field theory calculations(SCFT).Using this approach we observed various microstructures of cylinder-forming DBCPs at different confinement dimensions and surface fields.From detailed searching for the microdomain morphologies,an obvious conclusion is that the interactions between the confinement surface and the polymers have a great effect on the self-assembly.Most of the microstructures are unique and not reported in bulk or under planar and cylindrical confinements.  相似文献   
60.
Five new diacid amides of di-cholesteryl L-glycinates were designed and prepared.The compounds with linkers containing 0,1, 2,3,or 4 methylene units are denoted as 1,2,3,4,and 5,respectively.Their gelation behaviors in 25 solvents were tested as novel low-molecular-mass organic gelators(LMOGs).It was shown that the length of the linker connecting the two-cholesteryl residues in a gelator plays a crucial role in the gelation behavior of the compound.1 gels 11 of the 25 solvents tested at a concentration lowe...  相似文献   
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