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211.
The importance of including specific monomer structures, local correlations, and “equation of state effects” into the statistical thermodynamics of polymer blends is accomplished by developing and applying the lattice cluster theory. This new theory provides systematic corrections to Flory-Huggins theory from local correlations and describes polymers as containing structured monomers that extend over several lattice sites. 相似文献
212.
Polyoxometalates (POMs)containingKegginmoi etieshavebeenreceivingextensiveattentioninrecentyearsowingtotheirgreatfundamentalandpracticalinter est .1Especiallytheunusualelectronicproperty (highnegativecharges) ,oneofthemostimportantpropertiesofPOMs ,haspoten… 相似文献
213.
This paper describes the development of analytical methodology for the separation of naphthalene-2,3-dicarboxaldehyde (NDA)-derivatized substance P (CBI-SP) and five lysine-containing metabolites by micellar electrokinetic chromatography (MEKC). The effect of surfactant composition and organic modifiers on the separation was investigated. The final separation buffer consisted of 80 mM sodium cholate in 50 mM N-tris (hydroxymethyl)methyl-2-aminoethanesulfonic acid (TES), pH 7. All six lysine-containing peptides were separated under these conditions. 相似文献
214.
215.
稳态实验考察经模拟道路老化的全配方稀燃Nox捕集催化剂上的Nox还原 总被引:1,自引:0,他引:1
Fully formulated lean NOx trap(LNT)catalysts of the type Pt/Rh/BaO/Al2O3 were prepared with and without incorporation of CeO2-ZrO2 in the washcoat,and their NOx reduction behavior was evaluated in steady-state,continuous flow experiments.In the fresh state, the CeO2-ZrO2 addition was found to exert little effect on NOx reduction activity using H2,CO,and NH3 as the reductants.However,after simulated road aging,NOx reduction activity was significantly impaired for the CeO2-ZrO2-free catalyst,whereas the perfo... 相似文献
216.
本文提出并实现了一种新的穆斯堡尔谱——时间相关穆斯堡尔谱。这是利用两步衰变119mTe→119Sb→119Sn而获得的。测量了110keV 119mTe加1015稳定Te/cm2注入并经600℃退火的样品在不同测量时间内的穆斯堡尔谱,分析了各谱线随ξ的变化。这里ξ是我们定义的参量,它等于ΦTe/Φ总,由退火时刻ta关键词: 相似文献
217.
Optimality of embeddings of logarithmic Bessel potential spaces 总被引:2,自引:0,他引:2
218.
We show how general principles of symmetry in quantum mechanics lead to twisted notions of a group representation. This framework generalizes both the classical threefold way of real/complex/ quaternionic representations as well as a corresponding tenfold way which has appeared in condensed matter and nuclear physics. We establish a foundation for discussing continuous families of quantum systems. Having done so, topological phases of quantum systems can be defined as deformation classes of continuous families of gapped Hamiltonians. For free particles, there is an additional algebraic structure on the deformation classes leading naturally to notions of twisted equivariant K-theory. In systems with a lattice of translational symmetries, we show that there is a canonical twisting of the equivariant K-theory of the Brillouin torus. We give precise mathematical definitions of two invariants of the topological phases which have played an important role in the study of topological insulators. Twisted equivariant K-theory provides a finer classification of topological insulators than has been previously available. 相似文献
219.
220.
S.I.S.向量随机测度在弱拓扑及相容拓扑下的收敛性 总被引:1,自引:0,他引:1
本文主要研究s.i.s.向量随机测度在弱拓扑及相容拓扑下的收敛性,给出了s.i.s.向量随机测度在弱拓扑 容拓扑下的Vitali-Halm-Saks定理,作为应用,我们建立了R^1-值有界可测函数关于Banach空间值s.i.s.向量随机测度的随机积分的收敛定理,并得到了具typep的Banach空间中s.i.s.向量随机测度的大数定律及中心极限定理。 相似文献